In the production of publications and book-type products, more than 30 options for fastening book blocks are used, which can be combined into 14 types and 5 methods (Table 5.1): thread sewing, wire sewing, adhesive seamless fastening (SBS), sewing-adhesive fastening (SHKS) and mechanical fastening.

Each method has its own advantages and disadvantages, which determine its primary use in the production of one or another type of book products and white goods. The characteristics of each method indicate the financial and labor costs per unit of product, which are discussed in detail in the discipline “Design and Calculation of TBPP”, as well as the impact of the block bonding operation on the quality of the finished product. Greatest use by the end of the 20th century. in Russia and abroad they received tetrad sewing with threads without gauze, saddle stitching with wire and adhesive seamless binding with milling of the spine.

Notebook sewing with threads without gauze ensures high strength, durability and good opening of book products. It can be successfully used in small-, medium- and large-scale production of books and white goods, since leading machine-building companies produce a large number of machines, automatic machines and units that make it possible to mechanize and automate most of the bookbinding operations.

Table 5.1

Wire saddle stitching is widely used in the production of small-volume books, school notebooks and various documents due to its simplicity and low labor and material costs. Sewing with wire and especially tetrad stitching is finding very limited use due to the successful development of adhesive and mechanical fastening methods.

Adhesive seamless fastening methods in the second half of the 20th century. have significantly replaced sewing methods of fastening blocks due to the small number of operations and extensive mechanization and automation of production, good openability of finished products, but their disadvantage is the high demands on the selection of materials (glue to paper), strict adherence to technological process regimes, on which they largely depend strength and reliability of adhesive joints and, consequently, the service life of book products. Sewing-adhesive fastening combines the advantages of sewing and adhesive fastenings (low labor intensity and high economic indicators, high strength and good openability), but, unfortunately, it is not widely used in Russia and the CIS countries.

Mechanical methods of fastening blocks are used mainly in the so-called noteless technology, in small- and medium-scale production of white goods and some types of book publications (for example, catalogs of semiconductor devices and other products of rapidly developing industries), since they make it easy to remove individual sheets and add block with additional prints. Among them, fastenings with combs and spirals have become predominant, ensuring full disclosure of a publication or product, thanks to the mass production of simple, affordable desktop, small-sized and easy-to-use equipment for small businesses.

Fastening with clips and locks has limited use in the production of plastic and cardboard folders for storing various archival documents, as it makes it easy to replenish their contents. Two types of permanent fastenings - screws and rivets - also have limited use: they are used mainly in the production of photo albums and stamps (stock books).

5.2.1. Block sewing with threads

Block sewing with threads can be done with a single-thread knotted stitch or a double-thread chain stitch (Fig. 5.6).

Knotting sewing is characterized by the use of long (about 10 cm) stitches, their loose tightening and the presence of hanging ends of the thread at the bottom of the block near the tied knot. This type of sewing is used in foreign practice in the production of small-volume publications with covers and binding covers, complete with an insert and intended for children of preschool and primary school age. To fasten a block, two or three stitches are usually enough, so the labor intensity of fastening blocks with this type of sewing is low. This type of sewing has not found application in Russia and the CIS countries.

Sewing blocks with saddle stitch threads A two-thread chain stitch is made using special Singer sewing machines class 300 model 104, in which the seam is formed with one needle and one hook, which acts as a shuttle. The length of the stitches can be adjusted from 6 to 11 mm depending on the height of the block: shorter stitches are usually used when making small-format publications and products (for example, passbooks) with covers. The “De Flores” unit model SS/T (McCain, USA), in which this type of fastening is carried out, allows processing blocks with formats from 78 * 90/32 to 70 * 100/8 with a thickness of up to 5 mm at a speed of 60 -70 blocks/min. A production line based on this unit was successfully operated for a number of years at the Children's Book Production Association (Moscow) in the production of bound publications for preschool and primary school children.

Block sewing with tucking threads can be carried out with a chain two-thread seam on “heavy type” sewing machines, for example class 222 (Podolsk plant, Russia). When implementing this method of fastening blocks, it is recommended to use thin types of printed paper with a surface density of 50-60 g/m2, notebooks - only with fractional cutting (with machine direction along the spine) and strong threads made of synthetic fibers with a high relative tensile elongation, linear density in the range of 64-82 tex (g/km) and a breaking force of about 15-18 N (1.5-1.8 kgf). During the sewing process, the thread seam should be 4-5 mm from the edge of the spine of the block. If these conditions are met, high strength and good opening of book editions of large and medium formats will be ensured.

Sewing with sewing threads is quite widely used abroad in the production of school textbooks and other publications for selective reading - encyclopedias, reference books, dictionaries, technological instructions, etc. In Russia, this method is used mainly in the repair of library books.

5.2.2. Notebook sewing with threads

When sewing book blocks with threads, each notebook of the completed block is fastened with several (3 to 6) stitches, with each stitch fastening the adjacent notebook in two places with a single and double thread. Notebook sewing is done on specialized and universal thread sewing machines. Specialized thread-sewing machines are designed for sewing blocks without gauze using a simple brochure stitch, which is used in medium and large-scale production of book publications of significant volume, the blocks of which are further processed on automated production lines and units, on which, during the processing of blocks, the spine material that provides a strong connection between the binding cover and the block; it is not sewn, but glued. Such machines consist of a feeder, a saddle-shaped stationary table with a chain conveyor and pushing rollers, a glue machine, a swinging table with mechanisms for piercing needles and gates, a sewing carriage with sewing needles and hooks, a thread feeder and a receiving table with a pushing bar.

Universal thread sewing semi-automatic machines and automatic machines allow you to fasten blocks with two types of sewing on gauze and without gauze using, respectively, simple and adjustable binding stitches and simple and adjustable (or combined) brochure stitches (Fig. 5.7).

Binding sewing on gauze is different in that during the process of notebook fastening of the block, a spine material (printing gauze or non-woven material) is sewn to the spine, designed to securely fasten the binding cover to the block. In this regard, universal thread sewing machines are equipped with a gauze feeding mechanism and a device for forming a gauze loop between the blocks, which is necessary to obtain gauze valves.

When preparing a thread sewing machine for operation, the feeder magazine is adjusted according to the height, width and thickness of notebooks, and its counting and distribution device is adjusted according to the number of notebooks in the block. The height of the notebooks also adjusts the position of the nearest drive of the chain conveyor of the fixed table from the pushing rollers that transfer the notebooks to the swinging table of the sewing machine. The glue machine is adjusted in height so that the glue strip is applied to the notebooks with a distance of 1-1.5 mm from the spine fold. Adjustment of the thickness and width of the adhesive strip in sewing machines is not provided, therefore their size when gluing the outer notebooks, preventing possible separation of the notebooks from the block during subsequent transfer operations, can only be adjusted by changing the composition, concentration and viscosity of the glue.

On the machine's oscillating table, the position of the folding angle is adjusted to half the thickness of the thickest notebook in the block to ensure the exact position of the stitches on the spine folds of the notebooks of the stitched block. The adjustment of the pushing bar is also important for the quality of stitched blocks: the amount of pushing of stitched blocks on the receiving table during a machine operation cycle should be equal to the thickness of simple block notebooks, since only under this condition can the required thread tension and high sewing density be obtained. The movable wall of the receiving table is set to the height of the stitched blocks with a minimum gap that takes into account the tolerances for folding notebooks.

When changing the type of sewing and the format of notebooks, readjustments of the sewing machine are also made. Sewing tools are installed and secured in accordance with the required type of sewing and block height, using preliminary marking of one of the notebooks according to the installation tables. A set of sewing needles and hooks is placed on the sewing carriage and needle bar, securing them in holders and chucks, respectively. Piercing needles and gates (thread guides) are installed on the corresponding slats of the swinging table, and the piercings are against each sewing needle and each hook, and the gates are to the right of the hooks at a distance of 9 mm. The mechanism for leveling the notebook before sewing is set to a value greater than the indentation of the outermost top stitch from the top edge of the notebook by 15 mm.

The number of bobbins of thread must correspond to the type of sewing and the number of stitches, which are set depending on the format and proportion of the paper sheet (Table 5.2). When sewing on gauze, a roll of printing gauze or non-woven material with a width of w rm:

Where IN- height of the block before trimming.

In the process of sewing blocks, the spine material is unwinded from the roll as the stitched blocks move on the receiving table, and the gauze feeder mechanism is adjusted to the amount of formation of a loop of spine material between the stitched blocks, which is set in accordance with the thickness of the book blocks T b: at T b = 20 mm, the width of the flaps of the spine material after cutting the loops on the receiving table of the machine should be 18 mm, and for thicker book blocks - 22 mm.

Table 5.2

The responsibilities of the operator of a thread sewing machine include preparing the machine for work: readjusting the sewing machine and feeder in accordance with the type of fastening and the height of the block of the next order, threading threads and gauze, filling the glue bath with glue, loading the feeder magazine, monitoring the quality of sewn blocks, replenishing the sewing machine machine with consumables and feeder - complete blocks, as well as picking up finished products and placing them on a pallet, in a truck or on a conveyor to send the stitched blocks to subsequent operations. The responsibilities of the operators of semi-automatic thread sewing machines, which are equipped with small printing enterprises, also include placing notebooks on the stationary transport table of the machine, so its speed capabilities are not fully used. When manually placing block notebooks, the machine speed is set within 75-80 cycles/min, but even at such speeds, 20-23% of the time is spent on trays of completed and sewn blocks, replenishing consumables and troubleshooting when sewing blocks without gauze and 22- 25% - when sewing on gauze.

In modern thread sewing machines, the maximum technical speed of work has been significantly increased: up to 115 cycles/min in machines BNSh-6A and BNSH-6BA (Kiev ZPM, Ukraine), up to 140 cycles/min in automatic machines F145 (Stahl, Germany) and up to 300 cycles/min in the FH-Unika model (Kolbus, Germany). They do not have sewing machines configured for sewing with an adjustable brochure stitch, since when it is used, the quality of the stitched blocks deteriorates due to a significant (up to 2.5 mm) displacement of every second notebook due to the tension of the threads in the zigzag seam.

Notebook gluing when sewing blocks. The presence of a gluing machine in thread sewing machines has led to the emergence of a simplified version of the classical technology for processing stitched book blocks, eliminating the first four operations: crimping the spine and block, gluing and drying the spine (see Section 6). The use of this technology option in the production of multi-volume editions in bound covers did not produce positive results: finished books quickly lost their shape and were destroyed during use. The low quality of books made using simplified block processing is explained by the following: 1) starch glue and Na-CMC-based glue do not provide the required strength of the adhesive connection of notebooks; 2) the glue strips gluing the notebooks of the block to each other, even with strict adherence to the requirements for preparing the glue machine for work, are located too far from the surface of the spine (the outer edge is at a distance of 1-1.5 mm, and the inner edge is 3-4 times greater) , which leads to rapid destruction of the adhesive joint, since its inner layers experience the greatest loads when opening a book; 3) the glue strips turn out to be uneven and too wide due to the accelerated movement of the notebooks when they are pushed from the stationary table of the machine onto the swinging table; 4) the position of the adhesive strip depends on the thickness of the notebooks, therefore, when fixing the adhesive layer on the receiving table of the machine, the spine folds of complex notebooks and fractional parts of the sheet are at different levels with the rest of the simple notebooks of the block.

Notebook gluing is acceptable when producing small-volume publications and manually covering blocks with covers. Technological instructions for TBPP recommend the use of notebook gluing in cases where publications are printed on coated paper and have fold-out illustrations in notebook connectors.

Materials used for sewing. When sewing with notebooks, sewing harsh nylon threads in three folds of grade 50k (64/3) according to TU 17 RF 5999-73 or cotton matte “special” threads in 6 folds (trade number 30) with a linear density of 68.6 tex (g/km) are used ) according to GOST 6309 with a breaking force of at least 15.5 N (1.58 kgf).

Nylon threads are stronger than cotton threads at the same linear density, have a high relative elongation when stretched, and therefore rarely break when sewing. In a stitched block, they cause less thickening of the spine, since with the same strength they have a lower linear density (50k brand means: linear density r l= 50 g/km, k - nylon thread).

As the spine material, printed cotton-polyester gauze brand NSh (GOST 5196) is used, containing 25% nylon fibers with a hardness of (19 ± 3) cN (gs). Instead of gauze, non-woven material made from synthetic fibers is also used.

To glue the outer notebooks of a block during the sewing process, a 7% aqueous solution of Na-CMC with the addition of 4% PVAD is used, and for notebook gluing, glue based on PVAD with the addition of polyvinyl alcohol and Na-CMC is used.

Assessment of the quality of stitched blocks. The quality of book blocks stitched with thread is assessed by the following indicators: 1) the presence of the full number of good-quality notebooks of a given edition, the correctness of their arrangement in the order of signatures and the absence of upside down notebooks; 2) correct use of the type of sewing, number and size of stitches; 3) absence of sheathing, thread breaks and loose loops; 4) no displacement in the position of the folds in the spine and along the upper edge from the general plane (tolerance 1 mm); 5) no displacement of punctures from the fold line of notebooks (tolerance 1 mm); 6) the correct position and width of the glue strip on the outer notebooks [the indent of the glue strip from the spine fold of the notebooks should be (2±1) mm, the width of the strip - (2.5±1) mm]; 7) sewing density. When sewing on gauze, the evenness of the edges and the width of the gauze flaps are also assessed.

The quality indicators listed in the first three paragraphs are assessed visually and by comparison with an approved standard, and dimensional indicators are measured with a metal ruler with a division value of 1 mm. The sewing density is determined by the site foreman or laboratory worker using a PSh device, on which a block attached to the lower notebook is moved behind the upper notebook by a force of 9.8 N (a load weighing 1 kg), acting in the horizontal direction. The sewing density on this device is estimated by the amount of block shift A, the nominal values ​​of which, depending on the thickness of the block, were given in GOST 20254-74, which was in force until 1981, and repeated in the technological instructions for TBPP. Analysis of these values ​​showed that the average shift values ​​are proportional to the thickness of the block and can be calculated using the formula

Where T b - block thickness, mm. After calculating the value A should be rounded to the nearest 0.5 mm. It is more convenient to present tolerances on the nominal values ​​of sewing density in specific figures: when T b = 20 mm D= ±0.5 mm, at T b = 21-45 mm D= ±1.0 mm, and at T b > 45 mm D= 1.5 mm.

5.2.3. Factors affecting the strength of notebook thread sewing

The strength of notebook sewing with threads is determined on a dynamometer with a maximum load of up to 200 N (20 kgf) when testing the inner sheets or the entire notebook of the block for tearing. The strength of notebook sewing with thread depends on the type of sewing, the strength of the paper and the direction of its cutting in notebooks, the volume of notebooks, the strength and relative elongation of threads, the number and length of stitches, the presence and type of spine material.

From type of sewing The strength of the bonding of the notebooks to each other and the strength of the bond between the binding cover and the block depend. The highest bonding strength of the book structure is ensured by sewing blocks on gauze binding stitches, in which the gauze is securely connected to the block by zigzag outer stitch elements, and the binding cover in the finished book is secured to the block by the flaps of the spine material. The advantages of bookbinding sewing on gauze are used in the production of bound publications designed for medium and long service life and intensive use. A simple binding stitch is easy to set up, but the arrangement of stitches in adjacent notebooks one under the other limits its scope of application to joining blocks of medium-sized publications due to the large folds (thickening of the spine). When sewing relatively thin blocks, the number of diagonal seam elements fastening the spine material increases due to an increase in the number of stitches: along the height of the block, instead of one adjustable binding stitch, three simple binding stitches can be placed. The adjustable binding stitch, which gives half the thickening of the spine when sewing, due to the high strength of the fastening of both notebooks and the cover with the block, is used in the production of multi-volume large-format publications (with a large block weight) - encyclopedias, dictionaries, reference books, etc.

Sewing without gauze, carried out using simple and combined brochure stitches, provides very reliable fastening of block notebooks, allows for complete block processing (see Section 6) on automated production lines, but when it is used, the connection of the binding lid or cover with the block is carried out only by adhesive connection, strength and the durability of which depends on many factors (see subsection 1.2.9) and, to a large extent, on the production culture, the quality of the starting materials, strict adherence to the adhesive formulation and technological process modes. This type of sewing is widely used in the production of a wide variety of publications of significant volume, designed for a medium and long service life with low intensity of use.

The higher paper tensile strength, the higher the strength of the sewing fastener, but in this test the direction of its cutting is also of great importance. If the notebooks of a book block have longitudinal cutting, then when testing the inner sheets for tearing, the tensile force is directed towards the paper in the transverse direction, in which for all types of paper (except hand-made Whatman paper) it is always less than in the longitudinal direction. Of course, this does not mean that in order to increase this indicator, notebooks with cross-cut paper should be used, but when drawing up strength standards, this factor must be taken into account.

Notebook volume practically does not affect the tear strength of the internal sheets of notebooks, since when the first pair of sheets of a notebook is torn out, the paper is destroyed, and when two or three (or more) pairs of sheets are torn out, the threads break. When testing the pull-out of a whole notebook from a block, the strength indicator largely depends on the strength of the sewing and adhesive bonds of the notebook with adjacent notebooks and with the spine material, therefore, with an increase in the number of pages in notebooks, their tear-out strength increases. In pull-out tests of the first pair of inner sheets of 32-page notebooks sewn with four stitches, the pull-out force does not exceed 10 N (1 kgf), but when tearing out an entire notebook, the strength indicator is 12-15 times higher.

Threads used for sewing blocks have a breaking force of about 15 N (1.5 kgf), which gives approximately a 1.5-fold margin of strength for tearing out the inner sheets of medium-sized book notebooks sewn with four stitches. Of course, the more thread strength, the higher the strength of the sewing fastener, but using “thicker” (higher linear density, smaller trade number) and stronger threads is only advisable when sewing blocks with a stitch, in which the load on the sewing fastening when using a book is much higher. The use of threads made from synthetic fibers having a high relative extension when breaking, it not only reduces the number of thread breaks during the sewing process, but also contributes to less destruction of the block paper during its mechanical processing and when using the book, and increases the service life of the publication.

It has been established that the strength of fastening of sheets and notebooks of a book block is proportional to number of stitches, which, as indicated in table. 5.2, depends on the height of the block and is justified by the loads that increase when using a book with increasing publication format, thickness and weight of the book block. Stitch length has less impact on the strength of the book: doubling the length of the stitches increases the tear strength of the sheets by approximately 20%. Therefore, it is advisable to sew blocks of books of large format and volume using the maximum number of short stitches.

According to research conducted at the All-Russian Research Institute of Printing in the 1950s. , the pull-out strength of blocks, the rupture of blocks and the strength of the bond between the binding cover and the block depend on kind and the size of the root material. Two types of fabric with low surface density (cambric and calico) and two types of gauze - shaped and two-thread based - were selected as spine material. Research has shown that the maximum strength of the block is achieved by using two-strand gauze, which has increased tensile strength along the weft and large cells that ensure free penetration of glue to the folds of notebooks when gluing the spine and strong gluing of the gauze to the paper of the block and endpapers. Fabrics that are more tensile, but poorly permeable to glue, showed 21-29% lower strength in tests for block rupture and notebook tearing.

The strength of the connection between the binding cover and the block is maximum if the spine material is cut out along the entire height of the block, but when sewing blocks on gauze, this is not feasible, since when cutting the blocks, the edges of the gauze crumble. To prevent the spine material of a smaller size along the height of the block from interfering with the folding flaps of the cover material of the binding cover in the finished book, a roll of spine material is cut out with a width that is 35 mm less than the nominal height of the block [see. formula (5.3)]. In the finished book, the strip of gauze should be positioned symmetrically, at an equal distance from the top and bottom edges; In order for this to happen, when preparing the thread sewing machine for operation, the left edge of the gauze cloth is shifted to the upper edge of the block so that this distance in the stitched blocks is equal to 15 mm.

The minimum width of the flaps of the spine material, ensuring their reliable gluing with the endpapers, is calculated based on the minimum permissible gluing width of fabric binding materials with paper and cardboard, equal to 10 mm, a 20% safety margin and the size of the gaps when using thin cardboard for binding covers

Where R m - minimum spacing value, mm; k zp - gluing safety factor; w ms is the minimum amount of gluing of fabric to cardboard, mm.

At R m = 4.5 mm, k salary = 1.2 and w ms = 10 mm w mk = 17 mm, which is taken into account with a tolerance of 1 mm in the Material Consumption Standards and in the recommendations of technological instructions for TBPP. With an increase in the thickness of the block and the thickness of all materials of the binding cover, the size of the gaps and the width of the flaps of the spine material accordingly increase to 22 mm.

5.2.4. Sewing blocks with wire

Of the three methods of sewing blocks with wire (block saddle stitching, block stitching and tetrad stitching), the most widely used is saddle stitching due to its ease of use, extensive mechanization and automation, the ability to organize continuous flow production in large-scale production in all operations - from unit assembly to packaging of finished products. Its use requires a minimum of relatively cheap consumables - thin wire; it can be successfully used in both small and large printing enterprises, and in small-scale production it requires minimal financial costs for the purchase of relatively simple and high-performance equipment that requires a minimum of time for readjustment when changing an order. When using it in medium-scale production, semi-automatic insertion-sewing machines are used, which make it possible to assemble, fasten and cover from 22 to 31 thousand publications per shift, depending on their volume and format.

Modern inserting-sewing-cutting machines (sewing-cutting machines) are impressive in their capabilities: their maximum technical speed, depending on production needs, can range from 8 to 20 thousand copies of finished products per hour. By connecting a stacker and a packaging machine to the saddle stitcher, the finished product can be immediately sent to the warehouse or to the customer.

The disadvantage of this fastening method is that it is applicable only when assembling blocks with an insert, so the volume of publications printed even on thin paper does not exceed 128 pages.

Sewing with wire It is used relatively rarely - for binding publications in covers with a block thickness of 5 to 20 mm, produced in small and medium editions. Its disadvantages include poor book opening and quick tearing of the outer sheets at the attachment points when using the book.

Wire stitching on gauze was first practiced in the 1870s. in Germany. A machine for notebook sewing of book blocks with wire was designed and patented by Hugo Bremer in 1875/76 and was first demonstrated at the exhibition of the Exchange Society of German Booksellers in Leipzig in 1879. It was the first machine that made it possible to mechanize the very labor-intensive and tedious work of hand sewing book blocks , which contributed to the rapid spread of this sewing method in Europe and North America. Thread sewing machines began to be produced by the Bremer Brothers company (Germany) 5 years later, from 1884, and these two methods of notebook sewing of blocks coexisted for more than 80 years, but with the advent and widespread use of thread sewing machines, with which relatively slow-speed wire sewing machines semi-automatic machines could no longer compete; notebook wire sewing lost its position.

In the 50-60s, notebook sewing of blocks with wire was still quite widely used in the production of art books printed on highly calendered and coated types of paper, as well as in the production of any other publications intended for export, since sewing is fine (about 0. 5 mm) wire ensured “clean” turns of notebooks without the brown bone glue, which was used in previous years for gluing the spine, flowing into the punctures. In the 70s multi-equipment semi-automatic wire sewing machines have been discontinued, but tetrad wire sewing is still used in small-scale production of albums and atlases due to the wide technological capabilities of machines such as PSh-4M and 2ShP-4, which make it possible to fasten blocks up to 500 mm high and up to 125 mm thick with four to seven wires staples at speeds up to 65 cycles/min.

Block-by-block wire sewing technology. At small printing enterprises, saddle stitching and stitching with wire is carried out on single-equipment wire stitching machines type MPD of the State Research and Production Association "Splav" (Tula, Russia) and 4BPSh-30 or on multi-equipment machines 4BPSh-30/2 (JSC "Kievpolygrafmash" ", Ukraine). The MPD machine is designed for sewing blocks up to 14 mm thick, and 4BPSh-30 - up to 19 mm. On multi-device machines 4BPSh-30/2, from two to four sewing machines can be installed and blocks up to 8 mm thick can be fastened together.

When changing the order, wire sewing machines are adjusted to the type of sewing (saddle stitch or saddle stitch) and to the thickness of the block being sewn, while the position of the rotary work table is changed, a fixed stop is removed or installed that fixes the position of the spine of the block when sewing a stitch stitch, and the position of the sewing machine is adjusted in accordance with thickness of a book block. When preparing for operation of a insert-stitching sewing machine, it is necessary to adjust the position of the carriage of the sewing machine, the sewing heads and benders of the staple legs, and, depending on the thickness of the opened block, the amount of opening of the carriage grips and the gaps between the sewing heads and benders. Preparation for saddle stitching also includes adjusting the feeders in accordance with the format and thickness of the notebooks and covers, and the cutting section in accordance with the format of the publication.

To fasten book blocks with wire staples, printing wire in accordance with GOST 7480 or general-purpose low-carbon steel in accordance with GOST 3282 is used. GOST 7480 provides for the production of 11 types of wire with a diameter of 0.36 to 1.20 mm, of which for sewing blocks with bending the legs of wire staples, technological the instructions recommend using only seven: wire with a diameter of 0.4 to 0.7 mm for sewing blocks with a thickness of 0.5 to 5 mm and a diameter of 0.8 mm for thicker ones.

With a block height of up to 150 mm, they should be fastened with one bracket, with a height of up to 270 mm - with two, and with a higher height - with three brackets. When sewing blocks on wire stitching machines, the position of the staples along the height of the block is not fixed, but this is possible if you stick a cardboard stop (or two stops on both sides) on the table to get “transition” sewing. In the process of readjusting a collating-sewing machine and a saddle stitch for sewing with one staple, one of its edges should be in the middle of the block height, so that when sewing with a transition (shifting the staples in the next block by the length of the back of the staple), the staples in every second block are placed symmetrically relative to the middle of the block height. When sewing with two staples, the distance between them should be equal to half the height of the block, and when sewing with three staples - 1/3 of the height. Sewing with a transition reduces the likelihood of a stack of stitched blocks and finished publications falling apart during transshipment operations, before cutting blocks and when packaging finished products.

Technology of notebook wire sewing. Like tetrad sewing with threads, tetrad sewing with wire is performed on gauze, the width of the roll of which is determined by formula (5.3). When readjusting multi-equipment wire sewing machines 2ShP-4 and PSh-4M, the number of sewing machines is set in accordance with the height of the block: with a block height of up to 210 mm, two machines are installed, with a height of up to 270 mm - three, and with a higher height - four sewing machines. All sewing machines are installed at an equal distance from each other and so that the outer wire staples are located at a distance of at least 5 mm from the edges of the spine material, since otherwise, near the edges of the sparse gauze, the warp threads may shed and unravel during further processing of the blocks, which will lead to a decrease in the strength of the sewing fastener. The machine is configured for one of two possible sewing options: with one or two transitions, displacement of staples in adjacent notebooks of the block being sewn at a distance slightly greater than the length of the back of the staple, since the thickening of the spine of the block during notebook wire sewing is 2-2.5 times greater than with notebook sewing with threads. The sewing machine is set up for sewing with two transitions in cases where the block consists of a large number of relatively thin notebooks: 16-page or larger, but made from paper with low surface density and high bulk density with a block thickness of over 10 mm. Sewing 16-page notebooks with wire with a diameter of 0.4 mm with one transition allows you to reduce the thickness of the spine by 14%, and sewing blocks made up of 32-page notebooks - by 10%; when sewing with two transitions, the reduction in spine thickness is 19 and 14%, respectively.

In multi-equipment wire sewing machines, the size of the staples is not adjustable; sewing machines cut wire blanks 25 mm long, from which staples with a back length of 13 mm are formed. Taking into account the length of the backs of the wire staples, the distance between them l ms can be determined by the formula

Where IN- height of the block before trimming, mm; N n is the number of staple transitions when sewing; N c is the number of staples along the height of the block; l c - length of the back of the bracket, mm.

For sewing, wire of minimum thickness is used (0.36, 0.40 and 0.45 mm), since only half the thickness of the notebooks is stitched, which for dictionary paper with a surface density of 50 g/m2 in 16-page notebooks does not exceed 0.25 mm, and in 32-page notebooks with a maximum paper thickness of 90 microns, it cannot be more than 0.72 mm.

When receiving a new order, the driver marks the position of the spine material and wire staples on one of the notebooks (Fig. 5.8), and begins preparing the machine by installing the leftmost sewing machine, moving the overhead table to the rightmost position by turning the flywheel, after which the rightmost sewing machine installed in the leftmost position of the overhead table. The sewing heads of the middle (or middle) sewing machines are fixed at an equal distance from the outer machines and from each other. When sewing blocks with two and three staples, the sewing machines are moved to the right or removed. Devices for bending the legs of wire staples are installed against the sewing heads and are adjusted to a gap equal to half the thickness of the notebooks being stitched.

Wiring of wire of the required thickness begins with the far right device. The correct setting of the sewing machine is checked by flashing one notebook, raising the overhead table to its highest position. Installation of the gauze roll and refilling of the gauze is performed with the overhead table in the extreme right position. The most important operation is setting up the machine for sewing density, which is regulated by the amount of lowering of the overhead table for each cycle of operation of the machine. The sewing density adjustment scale is marked for the number of notebooks that can fit in a tightly stitched block 25 mm thick. In this regard, it is recommended to use a template of the same thickness so that during the sewing process you can quite objectively set the density of sewing blocks for any thickness of notebooks and paper.

During the sewing process, the machinist manually opens each notebook of the completed block and places it on the overhead table, pushing it against the side and front stops. At the end of sewing each block on the BShP-4M machines, the tape of the spine material is cut off manually with a knife; on 2ShP-4 machines, the feeding and cutting of gauze is mechanized. The driver removes the stitched blocks from the overhead table and places them on the work table, as it is filled, interrupting work on the machine, he controls the quality of the stitched blocks, places them in a stack, tucks the gauze valves between the blocks and transfers them to a pallet or truck.

The productivity of notebook sewing of blocks with wire on 2ShP-4 machines is 24 thousand notebooks per shift, while the technical utilization coefficient is 0.769. When working on BShP-4M machines, about 23% of the working time is spent on cutting and threading gauze, so the shift productivity does not exceed 18.5 thousand notebooks.

Quality control of blocks stitched with wire. Blocks stitched with wire are controlled by the following indicators: 1) by the number of staples; 2) by the number of transitions of staples when sewing; 3) wire diameter; 4) the distance between the staples; 5) the size of the gauze valves; 6) correct assembly; 7) absence of displacement of the wire staples relative to the radicular bend (tolerance - 1 mm); 8) absence of displacement of notebooks at the upper edge (tolerance - 2 mm); 9) tightness of fit and length of the legs of the wire staples (permissible gap between the ends of the legs is 1-5 mm); 10) when sewing on gauze - by the tightness of the gauze to the spine, the absence of distortions of the gauze, the evenness of the edges of the valves and the correct position of the edges of the gauze in relation to the outer brackets; 11) absence of damaged, deformed and contaminated blocks; 12) sewing density.

Monitoring of indicators for the number of staples and transitions, correct assembly, tight fit of staple legs and gauze, absence of damage and contamination is carried out visually, and dimensional indicators for which a tolerance is set in whole mm - using a metal ruler with a scale division of 1 mm. The diameter of the wire is controlled with a caliper or a TIC thickness gauge. The sewing density is measured, as for blocks sewn with thread, on a PSh device (see subsection 5.2.2).

5.2.5. Theoretical foundations of wire sewing

The work of V.D. Zhmutsky, carried out at MPI-MSUP in the 50s, led to the conclusion that the process of sewing book blocks proceeds in five stages, characterized by a stepwise increase in the applied load, its reaching a maximum and its stepwise fall as the legs of the staple advance in the thickness of the book block. At the first stage, the ends of the legs of the staple are pressed with a smoothly increasing force into the block and mainly compact the upper sheets, bending them at a certain distance comparable to the diameter of the wire. The highest compressive stresses in a deformable stack of sheets arise under the ends of the legs of the bracket and especially near the perimeter of the ends due to the concentration of stresses at the edges and tensile stresses in the nearest space. When the resulting compressive, bending and tensile stresses reach the strength limit of the sheet of paper, a portion of the sheet is torn out along the circumference of the end of the staple leg.

Since near the perimeter of the end of the staple leg and in the place of deflection of the sheets, the paper density is uneven (under the end of the staple, the air in the pores and capillaries of the paper is compressed, and near the perimeter it is displaced beyond its limits), stress dissipation is inevitable along the radius of the circle of the end of the staple. As a result, the average diameter of a disk pressed and extruded from a sheet of paper (Fig. 5.9, A) turns out to be less than the diameter of the wire by an amount approximately equal to the thickness of two sheets of paper in the block.

With further movement into the depth of the block, the leg of the staple compacts the underlying sheets, on which pressure is no longer exerted by the end of the leg, but by the torn out disk or disks of compressed paper. After pressing four to seven sheets (depending on the diameter of the wire, the thickness and volumetric mass of the paper), a paper cone is formed under the end of the staple (Fig. 5.9, b) with an apex angle of about p/2 rad (90°). The second stage is characterized by a constant value of force required to penetrate the paper cone into the underlying sheets. During this stage, the paper build-up at the end of the leg acts as a cone-shaped wedge, creating large compressive stresses with its tip on the next sheet and tensile stresses in several upper sheets, as a result of which tears are formed in them mainly along the machine direction of the paper.

The third stage occurs when the leg of the staple with a paper cone pushes through the last sheets of the book block (Fig. 5.9, V). Since these sheets do not have a solid support under them (since the swinging side bars of the sewing machine are still lowered), when they are pressed with the staple leg, tearing out of paper particles whose dimensions are larger than the area of ​​the end of the leg is inevitable.

At the fourth stage, the piercing force decreases sharply, since the movement of the legs is prevented only by the frictional forces of the paper in the pierced holes. At the end of this stage, the back of the staple touches the top sheet of the block and compaction of the top sheets with the staple begins. In the final, fifth, stage, the legs of the staple are bent, during which the greatest compressive stress is experienced by the lower sheets near the pierced holes, since only the paper of the block serves as support for the bent ends of the legs of the staple.

5.2.6. Factors affecting the strength of bonding blocks with wire

The strength of the sewing fastening of book blocks with wire is determined by the tearing force of a sheet, cover or notebook on a dynamometer equipped with wide jaws for fastening the block, sheet or notebook. The sewing strength indicator depends mainly on the sewing mode and three technological factors - the direction of cutting the paper in the block, the tensile strength of the paper and the number of staples with which the block was sewn or the notebook was sewn to the spine material.

Sewing mode the coefficient of block compaction should be considered at the last stage of formation of the wire staple in the wire sewing machine (see subsection 5.2.5). As studies conducted at the Department of Technological and Industrial Engineering at Moscow State University have shown, the strength of the fastening of sheets in a block depends on the accuracy of setting the sewing machine to the thickness of half a notebook when sewing blocks in saddle stitch and to the thickness of the block when sewing in a saddle stitch. It has been established that at the moment of bending the legs of the staple, the position of the pushing bar of the sewing machine in relation to the swinging bars of the mechanism for bending the legs of the staple must exactly correspond to the thickness of the block with the compaction coefficient TO c = 1 [see formula (3.7)]. A decrease or excess of this indicator by 10% (up to values ​​of 0.9 and 1.1) leads to a loss of strength by 18-21% (Fig. 5.10).

Technological factors. When testing sheets for tearing and when using a book, the forces are directed perpendicular to the spine line, therefore, from the point of view of strength, transverse cutting of sheets in a block is preferable, since the force in these cases is directed along the machine direction of the paper, along which the strength of the paper is always higher than with force directed perpendicular to it. However, cross-cutting is only permissible when using thin paper in publications designed for selective reading.

The greater the tensile strength of the paper, the higher the strength index, therefore the highest values ​​of bonding strength are ensured by the use of paper No. 1, consisting only of cellulose, without fillers or with a low content of fillers, with increased values ​​of surface density and thickness. The more staples a block or notebook is sewn with, the higher the strength of their fastening. Numerous tests carried out at the Department of TP and PP of Moscow State University showed that the dependence of the pull-out force F depending on the number of staples when sewing N has the form of a straight line emanating from the origin. In this regard, in the production of publications for children and other publications designed for intensive use, one should not skimp on wire: sewing with three staples instead of the usual two increases the fastening strength of the publication by 1.5 times, and the cost of a wire staple is many times lower than the cost of paper and all printing production of brochures or books.

5.2.7. Adhesive seamless bonding of blocks with spine milling

Attempts to simplify the technology of fastening book blocks, to replace notebook sewing with threads by fastening block sheets with glue, have been made for a long time. The modern principle of adhesive seamless fastening (GBS) was proposed in Austria in 1811. In the early 1900s, a significant number of small-format “pocket” publications were released in a number of countries, the sheets of which were fastened with bone glue with a large addition of glycerin to increase its elasticity, but strength and the durability of such books left much to be desired. The date of the real birth of CBS can be considered 1936, when the polymerization reaction of vinyl acetate was carried out in Germany and a polyvinyl acetate dispersion (PVAD) was obtained, which ensures high bonding strength of sheets of paper and preservation of the strength properties of the adhesive joint for a long time. In Russia, KBS began to be used in 1948, using foreign equipment purchased in England, and later in Switzerland. In 1955, hot melt adhesive was produced in the USA, which began to be used for CBS in European countries (Germany, England and France) in 1965, and in Russia and the CIS countries - in 1970.

The relatively rapid spread and development of this method of binding book blocks is explained by a number of its advantages: 1) high speed and low labor intensity of the process, which practically do not depend on the volume of the publication, the number of notebooks in the block and the thickness of the block; 2) the possibility of organizing continuous flow production for most of the operations in the technological chain of stitching and binding processes; 3) a significant reduction in financial costs and production time. The disadvantages of this method of bonding blocks include the dependence of the strength indicators of the CBS on the type of paper used, the correct selection of glue for the paper, the need for strict adherence to the technology and processing modes of semi-finished products at all stages of preparing the spine surface and the gluing process.

KBS technology using PVAD. To carry out adhesive seamless fastening of blocks of book editions in a cover using “cold” (normal room temperature) glue, the Müller-Martini company (Switzerland) released in 1998 semi-automatic “Amigo” with a productivity of 1500 copies per hour and “Tiger” automatic machines , “StarPlus”, “Trend-binder” and “Corona” with maximum technical speeds of 60, 116, 125 and 200-300 cycles/min, respectively. On KBS semi-automatic machines, only three operations are performed: 1) spine milling; 2) gluing the spine; 3) covering the block with a cover. Loading the machine after pushing the blocks along the top edge and onto the spine and removing the products is done manually. Natural drying before three-sided cutting after stacking publications in small piles is carried out on a work table or on the folding shelves of a truck.

In large-scale production of cover publications, multifunctional units are used that perform the following operations: 1) colliding blocks; 2) deep milling of the spine; 3) surface milling; 4) cleaning the spine from paper dust; 5) preliminary gluing of the spine; 6) short-term drying; 7) secondary sealing of the spine; 8) covering the block with a cover; 9) short-term high-frequency heating of the radicular zone. Cooling and final drying of the semi-finished products of the publication take place on a long conveyor, which transfers them to the separation of doubles or to three-sided trimming.

For the production of bound editions, the Kolbus company (Germany) produces three modifications of KBS machines - "Ratiobinder KM 470", "Systembinder KM 490" and "Systembinder KM 495" with a maximum technical speed of 100, 166 and 216 cycles, respectively. min, and the company "Siegloch" (Germany) - automatic machines SB-3000 and SB-6000 with a maximum technical speed of 100 cycles/min. An important difference between the KM and SB-3000 units is that in the former, the edging of the block spine is made with transverse cutting material, and in the SB-3000 unit, with longitudinal cutting material. The KBS machine is included in the production line, which includes a picking machine and a conveyor for natural drying and cooling of coated or edged blocks (Fig. 5.11).

The operation of pushing the blocks together before milling the spine is necessary in order to maintain tolerances for dimensional accuracy and the absence of skew of the spine and top margins in the finished edition during the KBS process; in production lines based on KBS units, it is performed on a vibrating table when transferring blocks from the picking machine to the unit.

In KBS units, the completed blocks are carried over the actuators using an endless chain conveyor consisting of links with flat clamps, the number of which depends on the number of operations performed, the operating speed of the unit and the technologically required time for folding and securing the adhesive layer. Therefore, in different models of KM units from the Kolbus company, the number of links varies from 15 to 39. When preparing the KBS unit for operation, the input of the block spines from the clamps is adjusted in accordance with the thickness of half of the block notebooks and the tightness of the spine folds. Technological instructions recommend that the amount of cutting of the spine folds during the milling process be set taking into account the volume of notebooks of the block: if the blocks consist of 16-page notebooks, then the amount of cutting of the folds should be no more than 3.5 mm, and if from 32-page notebooks - no more than 5 mm (Fig. 5.12).

These recommendations need to be revised, since they were established for KBS units, which were discontinued shortly after the release of relatively small series; It is also possible that the folding machines and folding devices of book and magazine rotary printing machines produced in the 60s folded notebooks with a very low fold density of 3-4.5 mm. But with modern folding equipment, the accuracy of folding is significantly increased, so it is too wasteful to convert 2.5-3% of the paper into chips when milling the spine. Let's explain these figures with a simple calculation: in 32-page notebooks with maximum paper thickness d b = 90 µm = 0.09 mm and compaction coefficient TO c = 0.90 the thickness of half the notebooks (8 sheets) in the spine will be equal to d k = 8H d b/ TO c = 8Х0.09: 0.90 = 0.8 mm. With a tolerance of +0.2 mm, 4 mm of “extra” paper is milled, which, with a block width of 135 mm (for the most common format 84ґ108/32), is (4:135)×100% = 3%.

The purpose of the first deep milling is to remove all the spine folds of the block, including the folds of the internal sections of the notebooks. On KBS units, this operation is performed sequentially with two cutters at different milling depths in order to reduce the likelihood of large particles of paper being torn out. When repeated milling, a kind of cleaning of the rough rough surface obtained during the first milling is carried out, large paper tears are eliminated, and the average depth of irregularities is reduced. This is achieved due to a significantly (5-10 times) smaller milling depth and the use of various abrasive materials glued to metal discs instead of cutters.

Paper dust closes micropores and the mouths of paper capillaries, complicating the processes of wetting and adhesion during subsequent operations of gluing the spine, so removing dust with rotating brushes and suction greatly contributes not only to improving working conditions, but also to obtaining a reliable adhesive seam of the adhesive joint.

It is recommended to do the primary sealing with a relatively thin layer of glue of reduced concentration and viscosity, since its purpose, as in the previous operation, is to create conditions for wetting the surface and deep absorption of a relatively low-viscosity and more liquid layer of glue compared to the second, main layer. Primary gluing of the spine is carried out with low-viscosity polyvinyl acetate dispersion (PVAD), undiluted or diluted to a dry residue content of 45%, with a conditional viscosity of 45-60 s according to a Navy viscometer. The short-term irradiation with quartz infrared lamps intermediate between two gluings of the spine can only be conditionally called drying, since its main purpose is to create a temperature gradient (see subsection 1.3.5), under the influence of which the moisture of the glue first rushes deep into the block, and after covering with the cover or edging the block with spine material _ and to the surface of the spine.

The purpose of the secondary sealing of the spine is to create a relatively thick and durable film, so this operation uses undiluted PVAD with a conditional viscosity of 60-80 s according to the Navy viscometer, which ensures high cohesive strength of the adhesive joint and the required durability of the publication. After covering with a cover or gluing the spine material (and on the SB-3000 and SB-6000 units from Ziegloch - after edging the spine), the spine zone is subjected to high-frequency heating in order to quickly remove moisture from the adhesive layer and the spine zone of the book block in the process of its further natural drying on conveyor belts and on pallets or in trucks before three-sided cutting.

KBS technology using hot melt adhesive. In this version of the KBS with spine milling, hot melt adhesive is used, which contains a vinyl acetate copolymer and various additives that increase elasticity, stickiness, reduce the melting temperature range and slow down the aging process. For example, in the composition of the domestic hot-melt adhesive TK-2P, the main component is a copolymer of vinyl acetate with ethylene, the additive that plasticizes and reduces the melting temperature range is paraffin, and the additive that increases stickiness is pentaerythritol rosin ester. The density and operating temperature of hot-melt adhesives depend on the composition and quantitative ratio of the main components in it (since the amount of aging inhibitors does not exceed 2%). For most formulations, the density of hot-melt adhesives is approximately 0.95 g/cm 3 , and the operating temperature range is in the range of 140-180°C. In practice, it is preferable to use hot-melt adhesives with a lower operating temperature range, about 140-160°C, since at higher values ​​it not only increases the hardening time of the adhesive layer, but also accelerates the process of thermal destruction of the copolymer in the finished product.

When preparing the KBS unit for operation, the gaps between the clamps of the chain conveyor and the cutters of the cutters are carefully adjusted, since the quality of preparation of the spine surface depends on this. During the first milling, 60 to 80% of the part of the spine protruding from the clamps is sphereized. This value depends mainly on the indicators that determine the tensile strength of the block paper: surface density, bulk density, degree of sizing and cutting direction. If the tensile strength of the paper is low, 60-70% of the part of the spine protruding from the clamps should be removed, since with a higher value of this indicator, large tears of the paper are possible, which cannot be removed during subsequent processing of the spine with a second cutter and abrasive materials.

When fastening blocks of publications designed for intensive use, to increase the strength of the KBS, narrow transverse grooves are milled along the entire height of the spine of the blocks using a special mill. The width, height and pitch (the distance between adjacent grooves) are set in accordance with the degree of sizing, composition (number) and type of paper finishing, since these indicators determine the completeness of wetting and the depth of penetration of the glue into the pores of the paper. The width of the grooves can vary from 0.3 to 0.5 mm, the depth from 0.5 to 1.0 mm, and the pitch from 4 to 8 mm. If the blocks consist of weakly glued paper No. 2 containing wood pulp, then use a cutter with cutters 0.3 and 0.4 mm thick, the depth of the grooves is set within 0.5-0.6 mm, and the pitch between them is 6-8 mm. When milling the spine of blocks consisting of glued and high-glued, calendered and high-calendered paper with a smoothness of over 120 s, containing only cellulose, the groove width is increased to 0.5 mm, the depth is increased to 0.8-1.0 mm, and the pitch is reduced to 4-6 mm.

The gaps between the milled spine and two to four rollers of two glue spreaders of KBS machines and units are set in a certain order and to the amount specified in the equipment operating instructions. In most machines, as the milled block moves to the section of covering or gluing the spine material, the gap increases from 0.1-0.5 to 0.5-1.5 mm, and excess glue is removed with a scraper or a rotating brush and a counter-rotation roller. Increased gaps between the glue rollers and the surface of the spine reduce the dynamic load when the glue comes into contact with the paper and the likelihood of excessive penetration between the sheets of the block. The thickness of the adhesive layer on the spine and the consumption of hot-melt adhesive are regulated by setting the gap between the milled surface of the spine and the counter-rotation roller or scraper that removes excess glue. It is recommended to set the gap in the range of 0.4-1.0 mm depending on the thickness of the block T b and (in the manufacture of editions with covers) on the surface density of the printing and cover paper. At T b £ 10 mm thickness of the adhesive layer d there should be d k = (0.5 ± 0.1) mm; at T b £ 20 mm d k = (0.65±0.15) mm and at T b > 20 mm d k = (0.8±0.2) mm.

When using printing paper with a surface density of over 70 g/m2 and burnt paper with a density of over 120 g/m2, the thickness of the adhesive layer should be increased towards a positive tolerance.

Variants of KBS with spine milling. In the 50s, the Ukrainian Research Institute for Special Types of Printing developed a version of the KBS with milling and reinforcement of the spine. A distinctive feature of this option is that after milling, transverse cuts are made on the spine, into which, after gluing the gauze, this spine material is pressed, connecting the sheets of the block with threads, increasing the strength of the fastening of the sheets in the finished book. To implement this method, Kharkov ZPM produced semi-automatic machines for seamless fastening of PBS, in which processing is carried out by screwing blocks placed in containers. When loading containers, plates are placed between the blocks, forming gauze valves and allowing for artificial drying of the roots of the blocks in a clamped state. The increased strength of the KBS with spine reinforcement has made it possible to use this method of fastening blocks for publications in a binding cover, designed for an average service life and intensive use, for example, in the production of school textbooks.

In units of the 650 type series (TWT plant, now the Stahl-Bremer company, Germany), designed for sewing-glue and adhesive seamless fastening of blocks with a shared edging of the spine, the spine is glued sequentially with three rollers, the first two of which are conical, rotated cut off tops in different directions. When the blocks move over the conical rollers, the notebooks and sheets in the notebooks are fan-shaped, alternately in both directions, as a result of which the spine edges of the notebooks and their sheets move relative to each other, providing access for the glue to the side surfaces of the sheets. It is argued that with this coating, the glue penetrates deeply into the spine and the sheets or notebooks are not only held in the spine by the adhesive film, but are also glued together.

This version of the KBS with spine milling is not widely used for the following reasons: 1) the uniform bending of the sheets is hampered by the uncut upper folds of the notebooks of the block; 2) the distance from the conveyor clamps to the surface of the glue rollers is not the same, depending on the thickness of the block and the serial number of notebooks in the block, as a result of which the bending radius and the relative shift of notebooks and sheets along the thickness of the block are different (Fig. 5.13);

3) notebooks and sheets of the block, oriented towards the top of the cone, can be deflected under insignificant loads from a thick layer of concentrated high-viscosity glue; 4) the sheets of each notebook, their edges in contact with the surface of the conical roller, also fan out from the top to the front edge of the block. All this leads to uneven coating of the root zone of the blocks and a decrease in the quality of their adhesive bonding.

5.2.8. Adhesive seamless bonding of blocks with partial destruction of folds

The purpose of seamless methods with partial destruction of folds is to preserve part of the spine folds, since paper is usually stronger than adhesive joints, and to use the advantages of notebook technology in terms of printing publications on full-size sheets, the processes of making notebooks and book blocks. These goals are achieved in three ways that are similar in nature: perforation of the spine folds, milling of several small zones (splines) and milling of the middle part of the spine (Fig. 5.14).

In all three variants of KBS with perforation of the folds and milling of part of the spine of the block, from 60 to 80% of the spine folds are destroyed, which, when gluing the spine, allows you to fasten the notebooks to each other, ensure the penetration of glue inside and glue the internal parts of the notebooks. These methods allow the use of only 16- and 8-page notebooks, since when using 32-page notebooks, weak tightening of their folds requires too great a milling depth, which makes it difficult for the glue to penetrate the inner parts of the notebooks of the block, significantly worsens openability and reduces the strength of the publications or products.

The most simple technology is the KBS technology with perforation of the spine folds, which can be performed on almost any folding machine (see subsections 2.4.3 and 3.3.1). Milling of splines and the middle part of the spine can be done individually or by screwing one or more cutters on special machines, since the movement of the block and cutter relative to each other usually occurs perpendicular to the line of the block spine. The depth of milling of blocks made from thin notebooks does not exceed 1.0-1.5 mm. To glue the spine, low-viscosity 33-40% PVAD is used, which ensures good wetting and deep penetration of the glue into the slots, between the folds of notebooks and between milled sheets. To increase the strength and durability of publications and products with covers, the milled part of the spine is glued with non-woven material or thin fabric. When making book products in a binding cover, the block is edged with the spine material extending onto the endpapers.

The KBS version with perforation of the spine folds is used abroad in the production of white goods, small-format and low-volume magazines, and publications of fiction with an average service life. Options of KBS with milling of splines and the middle part of the spine are used in the production of multi-volume editions of fiction, catalogues, stamp albums, etc.

5.2.9. Adhesive seamless bonding of blocks without destroying the spine folds

The idea of ​​using adhesive fastening of block sheets in notebook technology without destroying the spine folds of notebooks has long attracted printing technologists with its advantages: this option does not require the operation of milling the spine and converting about 3% of the paper into shavings, it allows you to obtain book spreads that are not damaged by sewing tools and materials, which are very convenient and desirable when reproducing works of art and geographical maps. Back in the middle of the 20th century. M.V. Balandin proposed an option for producing 16-page notebooks with a four-fold combined fold (Fig. 5.15), in which four single-fold sections of the sheet are positioned with the spines in one direction. This option could not be used industrially, since folding machines did not allow producing such notebooks with the required accuracy of combining all four spine folds. Other methods involve applying wide or narrow strips of liquid adhesive or hot melt adhesive to the intended folds in the printing press - after printing or (in web rotary presses) and during the folding process.

Single-fold notebook method. This method for the production of geographic atlases was developed at the All-Russian Research Institute of Printing and was used for some time in map publishing. Navigation maps used in sea and river voyages are printed on high-glued, thick and rigid cartographic paper, the gluing strength of which with PVAD glue is insufficient, therefore in this version of the KBS an alcohol-water solution of methylol polyamide resin was used, which, when applied twice with short-term intermediate drying, provides high strength and excellent frost resistance bone adhesive joints.

The method of fastening two- and three-fold notebooks in the spine folds with narrow (up to 4 mm) strips of liquid “cold” glue in the middle of the spine margins was implemented using systems of inkjet adhesive devices such as “Optimatic 6000” (company “Planatolwerke”, Germany), which can be equipped with folders for book and magazine roll-fed printing machines. Inkjet adhesive machines allow you to apply glue to the folded paper tape in a continuous or broken line of various widths, taking into account the absorbency of the paper and the volume of notebooks. In the simplest version, publications of 16 and 32 pages (with a three-fold combined folding with collation), printed and glued on such machines, require only trimming and packaging operations. Processing of multi-volume publications with covers and bindings is carried out on any KBS machines when the spine milling section is turned off.

A method for fastening notebooks along spine folds using hot-melt adhesive was developed in the laboratory of the TBPP All-Russian Research Institute of Printing. The method involves applying strips of hot-melt adhesive about 9 mm wide to the spine in a special section of sheet-fed printing machines. The bonding process itself can be carried out in KBS machines by melting strips of hot-melt adhesive in the high-frequency heating section of the spine zone of book blocks.

A version of KBS with preliminary application of strips of “cold” polyamide glue with a width of 6 to 10 mm in the middle of the spine margins in roll printing machines was developed at the Department of TBPP (now - technology of printing and post-printing processes) of Moscow State University. As the paper web moves toward the folding machine, the glue dries. Thermal welding of sheets of notebooks at the place of spine folds to a width of no more than 0.5 mm occurs until the spine fold of notebooks is obtained. Relatively wide strips of adhesive strengthen the paper in the spine area and guarantee heat sealing of all sheets, taking into account the tolerances for printing register accuracy and folding accuracy. The small width of the heat seal ensures good opening of the book edition, and the use of polyamide glue ensures frost resistance down to -50°C. This version of the KBS allows you to eliminate the skew of margins in finished books, which inevitably occurs in all versions of the KBS with spine milling due to weak tightening of the spine folds in notebooks.

Both variants of CBS with heat sealing of a pre-applied adhesive layer have not received industrial application.

5.2.10. Assessment of the quality of blocks bonded by KBS

When setting up the KBS machine and during its operation, the main attention is paid to the quality of preparation of the spine surface during the milling process, the thickness of the applied adhesive layer and the strength of the adhesive bond. The quality of the spine surface preparation is assessed visually by comparison with a reference block made of the same paper, or, in doubtful cases, by measuring the average depth of macro-irregularities of a sheet removed from the middle of the milled block. Technological instructions recommend measuring the depth of macro-irregularities at 10 points along the entire height of the spine with an interval of 15-20 mm and calculating their average value h cf, which, with good milling quality, should be in the range of 0.25-0.40 mm. Measurements are carried out with a reading microscope MPB-2 with a scale division of 0.05 mm.

The assessment methodology described above h c needs to be revised, since it does not meet the requirements of GOST 2789 and the international standard for assessing the surface roughness of printed paper. The method of technological instructions, in essence, suggests making a random sample of a controlled quality indicator, the volume of which, in order for it to be representative, must be at least 25 copies (in this case, measurements). GOST 2789 recommends measuring irregularities in a row, that is, making an instant sample in which the number of measurements of the controlled parameter can be reduced by an order of magnitude (maximum to three).

An analysis of the macrogeometry of the milled surface of the spine of the blocks showed that the degree of its development (and this is the purpose of milling the spine for CHD) is determined not so much by the depth of the macroroughnesses as by their number along the height of the spine and the shape of the recesses or peaks; for example, a symmetrical shape gives the least increase in spine surface. To take into account the degree of surface development, the author proposed introducing a coefficient of macro-roughness steepness into the assessment of the quality of milling the spine of blocks TO k as the ratio of the sum of the depths of irregularities to the base length (Fig. 5.16):

Where h i- uneven depth, mm; N- number of measured depressions; l- base length (distance between the left edge of the first and the right edge i th unevenness), mm.
The number of measurements of instant sampling can be reduced to 5, but if a significant difference in the quality of milling along the height of the blocks is noticeable, then measurements should be made in three places (in the middle and along the edges of the sheet), and the calculation h from the total sample - based on the results of 15 measurements.

The thickness of the applied hot-melt adhesive film can be assessed using a LI-3 measuring magnifying glass (GOST 8309) with a division value of 0.1 mm. When using PVAD, the boundary between the surface of the paper and the adhesive film is not visible, so the glue is tinted with an aqueous solution of auramine or chrysopheline dyes at the rate of 20-30 ml of a 3% solution per 10 liters of glue.

The strength of the KBS in laboratory conditions is measured on a dynamometer with a breaking force of at least 30 daN (kgf). Three sheets of the block are tested: two 15s from the beginning and end and one from the middle of the block. The strength of the KBS is assessed by the specific pullout force f, kN/m (kgf/cm), which is calculated by the formula

Where F i- values ​​of sheet pullout force, daN (kgf); N and - number of pullout tests on sheets; IN- block height before trimming, mm.

According to the standards developed by the Adhesive Products Institute (USA), the strength of the CBS is assessed using a four-point system (Table 5.3).

Table 5.3

Blocks bound and edged or covered with covers should not have splits (violations of the integrity of the adhesive joints of the sheets), but gaps between the sheets up to 0.2 mm wide are allowed, which are formed when the blocks are lowered from the clamps of the KBS machine before gluing the spine and subsequent operations. The penetration depth of the glue between the sheets of the block should not exceed 1.5 mm, but individual runs of up to 3 mm are allowed. When covering blocks with a cover, the width of the adhesive strips on the spine margins of the blocks should be equal to (5 ± 2) mm. Dimensions greater than 2 mm are controlled with a metal measuring ruler or tape measure with a stop that fixes the starting point.

The quality of the products of KBS machines should be checked no earlier than after 1 hour when the blocks are fastened with hot-melt adhesive and no earlier than after 3 hours when they are fastened with “cold” adhesives. When using express control methods, it is possible to significantly improve product quality through timely changes in processing modes, if the dependence of the strength of the CBS on the time of natural drying or cooling in the first hours of formation of the adhesive joint of the block sheets is known.

5.2.11. Factors influencing the strength and durability of CBS with spine milling

In the 60-70s. The Department of TBPP at Moscow State University carried out research work that made it possible to establish the influence of numerous factors on the quality of book publications bound by the most common type of CBS with milling of the spine of book blocks. These studies formed the basis of technological instructions for the production of publications with covers on the Jet-Binder, Rotor-Binder RV-5, etc. machines (Müller-Martini, Switzerland), which were equipped with many large printing houses in Russia and CIS countries. It was found that the quality of preparation of the spine surface and the strength of the CBS of book blocks are significantly influenced by spine milling modes and a number of technological factors associated with the physical, mechanical and physical and chemical properties of paper and glue.

Milling modes. Milling modes include the amount of spines coming out of the clamps, the size of the gap between the block clamps and the teeth of the cutter, the speed at which the blocks are fed to the cutter, and the sharpness of the cutters. The quality of mechanical processing of the spine is characterized by the macro- and microgeometry of its surface obtained after milling: the size of the contact area of ​​the adhesive layer with the paper, and at the molecular level - the number of active centers per unit area of ​​the rough surface of the spine. Since the fibrous structure of paper does not allow even approximately determining the true development of the surface when milling the spine, the average depth of macroroughness is considered to be an indicator of the quality of milling (see subsection 5.2.10 and Fig. 5.16).

The amount of spine exit from the clamp. As mentioned above (see subsection 5.2.7), when milling the spine of blocks, it is necessary to remove from 3.5 to 5 mm of the width of the spine zone. But when milling only 2-3 mm of the spine width, the depth of macro-irregularities can exceed the permissible value of 0.4 mm, therefore, with tetrad technology, a large exit of the spine from the clamps is milled in at least two steps, so that during “finishing” milling, the exit of the spine from the clamp does not exceed 1.5 mm.

The size of the gap between the clamps and the teeth of the cutter. Increasing the gap between the clamps and the cutter teeth from the minimum (0.5 mm) to 1 mm, by only 0.5 mm, increases the depth of macro-roughness by approximately 1.4-1.5 times, which in many cases leads to an unsatisfactory condition of the milled surface and low quality CBS. The gap size should always be set to the minimum that the quality of the cutter and the technical condition of the machine allow.

Milling speed. With increasing milling speed, the average depth of macro-roughness increases linearly, and the initial depth of macro-roughness at minimum machine speed depends on the size of the set gap between the block clamps and the cutter teeth and on the position of the sheets in the block (Fig. 5.17 and 5.19). With an eightfold increase in the speed of feeding blocks to the cutter (from 7 to 56 m/min), the depth of macro-roughness in the middle of the block increases by approximately 12%, and at the entrance and exit of the block - by approximately 1.5 times; in this case, the strength of the CBS decreases by approximately 25% (Fig. 5.18).

Sharpness of cutter teeth. As the cutter becomes dull, the average depth of macroroughness increases, and to the greatest extent - in the second half of the block and especially when the block exits the cutter (Fig. 5.19). This circumstance requires the operator to constantly pay attention and regularly check the quality of milling by comparing the controlled blocks with a reference sample.

Technological factors. The quality of book blocks after spine milling largely depends on the rigidity of the block paper and the bending resistance of the spine area protruding from the clamps of the main conveyor of the KBS machine during the milling process. The value of these parameters depends on the thickness of the block and the thickness of the notebooks and sheets of paper that make it up, its composition, volumetric mass (density), degree of sizing, thickness and cutting direction. Another group of factors is concentration, viscosity, temperature and thickness of the adhesive layer or glue consumption per unit of spine surface.

Thickness of block, notebooks and paper. The bending resistance of the block spine is the least for the outer notebooks and sheets of the block, since when the block is secured with the clamps of the main conveyor of the KBS machine, they bend like a fan and move away relative to the middle of the block. Therefore, at the first moment of the force action of the cutter teeth on the spine of the block, the outer sheets do not have support on the sheets of the middle part of the block. The last sheets of the block are in an even more disadvantageous position, since at the exit of the block from the cutter, the teeth of the cutter press the sheets even more away from the middle of the block, the air gaps between them increase, and the bending resistance of the remaining sheets decreases. For these reasons, the average depth of macroroughness turns out to be minimal in the middle of the block and maximum along the edges (see Fig. 5.19).

Paper composition. The fiber composition of the paper significantly affects the quality of the surface preparation of the spine of the blocks and the strength of the CBS. The influence of this factor is not clear: paper No. 1, which does not contain wood pulp, provides a more even structure of the milled surface, stronger adhesion of cellulose fibers to each other, but the relatively high bulk mass (density) and lower porosity make it difficult for high-viscosity glue to penetrate its capillaries and pores . The greatest strength of CBS is provided by paper No. 2, which contains a moderate amount of wood pulp, which increases the porosity and absorbency of the paper. High strength of CBS is also ensured by fine-pored intaglio printing paper, made from high-quality fibrous material, containing a significant amount (up to 22%) of fine filler.

Volumetric mass. The volumetric mass (density) of paper, if it does not contain a large amount of fillers, characterizes its porosity and, therefore, absorbency. Therefore, as a rule, all types of paper with a relatively low volumetric mass (machine smoothness), compared to calendered and highly calendered, provide higher strength of the CBS.

Degree of sizing. The high degree of sizing of offset and especially cartographic paper has a negative effect on the strength of CBS, since the rosin esters used for sizing domestic paper give it hydrophobicity, which impairs the wetting of paper with water-based adhesives. The use of glued and high-glued paper leads to a significant drop in the strength of the CBS, therefore, when using this method of binding in offset-printed publications, other indicators of paper that determine its rigidity are limited. The greatest strength and stability of results for CBS is provided by lightly glued letterpress paper No. 2.

Paper thickness. With adhesive seamless binding, the best indicators of strength and durability of book editions are provided by thin types of paper - up to 90 microns thick and a surface density of up to 70 g/m2. Thicker types of paper, due to their high rigidity, have a significant force on the adhesive connection of the sheets in the spine when using the book, leading to its rapid destruction; they are unsuitable for books designed for a long service life or intensive use. The use of offset paper with a surface density of 80, 100 g/m2 and higher is possible only under the condition of fractional cutting for publications designed for a short and medium service life and low intensity of use.

Cutting direction. Cutting the block paper into pieces provides the least force on the adhesive connection of the sheets when using a book, but during the milling process, especially with a dull cutter, tears often form in the cut paper beyond the macro-irregularities, which sharply reduces the service life of the book edition. It should also be taken into account (when selecting the concentration, viscosity and consumption of glue) that with fractional cutting the average depth of macro-irregularities and their number along the height of the block is always less than with transverse cutting. Cross-cutting of block sheets is acceptable and is recommended by technological instructions when using thin and low-strength types of paper, since in such cases the durability of publications is decisively influenced by the tensile strength of the paper and the degree of development of the spine surface during milling.

Concentration and viscosity of glue. On KBS machines with one-time gluing of the block spine, undiluted medium- or high-viscosity PVAD grades DF 51/15 VP, DF 50/7.5 VP, etc. are used. with a dry matter content from 50 to 55% and a conditional viscosity from 41 to 100 s according to the Navy viscometer. This dispersion provides high cohesive strength of the adhesive layer, but its adhesive strength with the glued paper of the block may be insufficient. In KBS machines with double sealing of the spine, the first sealing is carried out with a low-viscosity dispersion with a conditional viscosity from 18 to 35 s, and after intermediate drying - with a medium and high-viscosity PVAD with a conditional viscosity index from 32 to 75 s according to the VMS viscometer. Double gluing of the spine allows you to obtain high adhesive and cohesive strength of the adhesive connection of the block sheets.

Thickness of the adhesive film and glue consumption. As the thickness of the adhesive film increases to a certain limit, the strength of the adhesive seamless bond first increases and then decreases (Fig. 5.20).

The figure clearly shows that the maximum strength of the CBS occurs at a consumption of 50% PVAD equal to 800 g/m2. Simple calculations show that the average thickness of the adhesive layer is 0.736 mm, since the density of polyvinyl acetate r PVA = 1.19 g/cm 3, 1 kg of 50% PVAD has the volume V=920.17 cm 3 and density r 50 =1.087 g/cm 3. In any volume of 50% PVAD, the dispersion medium occupies 54.34%, and polyvinyl acetate - 45.66% of the glue volume. During film formation during the absorption and evaporation of the dispersion medium, it must be removed in an amount from 6.7 to 28.4% in order to form, respectively, a cubic and hexagonal arrangement of the solid phase of the adhesive.

At a consumption of 800 g/m2 of glue and with cubic laying, polyvinyl acetate creates an air-dry film with a thickness of 0.687 mm, with a hexagonal one - 0.527 mm, with an equiprobable one - 0.607 mm. In a dry adhesive film, the most likely option is a combined installation of PVA, therefore, its thickness will be approximately 0.6 mm. If the average depth

The macro-roughness is 0.4 mm, and the areas of the recesses and vertices are the same, then only 1/3 of the total amount of glue, about 0.2 mm of dry film, is spent on completely filling the macro-recesses. In this case, 0.4 mm of air-dry glue should remain on the surface of the spine. If, when assessing the quality of the block, the thickness of the adhesive film on the spine turns out to be less than this value, then this means that the consumption of PVAD is less than 0.8 kg/m 2, or the penetration depth of the glue between the sheets of the block is greater than the maximum permissible value of the average depth of macro-irregularities.

PVAD temperature. The greatest strength of the CBS is ensured if at the time of application the glue and paper are at a temperature of (20±2)°C. When the glue temperature decreases to 10°C, the strength of CBS blocks bonded with polyvinyl acetate dispersions from various manufacturers decreases by 1.1-1.4 times, but the greatest drop in strength is observed when the PVAD temperature increases to 30°C - by 1.5 -1.8 times, with the decrease being greater, the lower the initial viscosity of the dispersion.

5.2.12. Sewing and glue binding of book blocks

The sewing-glue method of fastening book blocks was developed at the LBV plant (Stahl-Bremer, Germany) in the 70s. According to this technology, the fastening of book blocks is carried out in two stages: first, the sheets of notebooks are fastened with thread staples during the process of folding the notebooks, after which, in the process of processing the completed block, the stitched notebooks are fastened with glue and edged with some kind of spine material.

For sewing notebooks, complex two-component (for example, viscose-polypropylene) threads are used, one of which serves as a kind of hot-melt adhesive during the sewing process. During the sewing process, the sewing machine forms a thread staple, pierces two holes with thin needles in the spine of the open notebook and pushes the legs of the thread staple into them. Bending and attaching the legs is done with tools heated to approximately 250°C, which melt the fusible component of the thermofilament and press the legs of the staple to the outside of the notebook. The legs of the staples are secured to the paper due to the natural cooling of the melt as the semi-finished product moves to the last spine folding operation.

In the original version, sewing notebooks with termion threads was performed with one to four sewing machines model 311, fastening each notebook with 2-8 staples, depending on the height of the spine. The devices were installed above the last transport table of serially produced folding machines produced by the TWT plant. Since 1983, the automatic sewing-folding machine model 341 was put into production, which is connected to folding machines of any manufacturer. The machine 341 implements the rotational principle of sewing with thermal threads in time with the operation of the folding machine; The length of the back staples with which each notebook is sewn is constant, and their number depends on the height of the spine. In small-scale production, sewing notebooks with thermal threads is performed on sewing machines model 301, when working on which notebooks are placed manually on a horizontal table under the sewing machine, and the sewing machine is turned on by pressing the pedal.

Adhesive bonding of notebooks and subsequent operations (edging and high-frequency heating of the spine zone) are carried out on specialized semi-automatic machines such as SB-3000 or on universal machines SB-6000 (Siegloch, Germany), which provide for partial edging of the block with spine material. This option of edging, in comparison with gluing cross-cut spine material, makes the block more compact and durable, since the flaps of the edging material attract the outer notebooks of the block to the adjacent ones, ensuring their more reliable gluing to the block.

Sewing and adhesive bonding of blocks makes it possible to obtain very high strength and durability of book editions in a binding cover, which, in these most important quality indicators, are very close to editions fastened with notebook threads. The advantages of this method of fastening blocks include the fact that it can be used with equal success in both large-scale and small-scale production of bound book editions.

Assessing the quality of notebooks sewn with thermal threads. The quality of notebooks sewn with thermothreads is assessed by the following indicators: 1) the accuracy of the position of the thread staples on the spine folds of the notebooks (tolerance 0.5 mm); 2) strength of welding of thread staple legs (nominal value 6 N @ 0.6 kgf, tolerance ±1 N @ 0.1 kgf). The first indicator is assessed using a LI-3 measuring lens with a division value of 0.1 mm, and the second - using a dynamometer with a maximum load force of at least 300 N (30 kgf), equipped with wide jaws for securing stitched notebooks.

Factors influencing the strength and durability of sewing-adhesive bonding of blocks. The strength and durability of the sewing-adhesive bonding of blocks depends on the strength of the thermal threads, the strength of the welding of the legs of the thread staples, the adhesive bonding of the legs of the staples and notebooks of the block to each other, the type and strength of the edging material. The strength of thermal threads is sufficient: it usually exceeds the strength of sewing threads No. 30, used for notebook sewing of blocks, by about 1.5 times. The strength of welding thread legs depends on the temperature of the working tools and the type of paper (Fig. 5.22).

With an increase in the temperature of the heating tools, the welding strength of the thermofilament legs increases, reaching a maximum value for many types of paper in the temperature range of about 250-265°C, after which it decreases. For calendered types of paper (for letterpress printing No. 1, offset No. 2, illustration No. 1), the optimal temperature for welding the legs is 255°C, and for coated letterpress printing - 265°C. As a rule, highly calendered and chalk-coated types of paper give approximately 1.5 times less welding strength than bulk-coated and calendered types of paper. For some types of paper, the welding strength of the thread staple legs decreases rapidly immediately upon reaching maximum strength or remains constant up to a temperature of 280°C.

In the process of gluing, edging and drying the spine of the block, the strength of the sewing-adhesive bond increases approximately 1.6-2 times and reaches an average of 10-11 N (1.0-1.1 kgf).

5.2.13. Mechanical fastening of book blocks

Mechanical methods of fastening book-type blocks that use metal or plastic fasteners or devices are called mechanical. Based on the type of hole formation in the root zone of the block and the type of fasteners and devices, mechanical methods of fastening blocks are divided into fastening with spirals and combs, screws and rivets, lock-clips and clips.

Bonding with spirals and combs. To fasten blocks with spirals, it is necessary to perform two operations: perforate the holes in the root zone and wind the spiral into the perforation holes. In large- and medium-scale production, perforation is performed on EX 380, 610 or 700 type machines (James Burn International, Sweden), in which perforation can be done sheet by sheet or in a stack of 3 to 30 sheets. In small-scale production, desktop “office” punchers or universal punching and scoring machines of type 2UPB-500 (Kharkov ZPM, Ukraine) are used. To fasten with metal or plastic spirals, small round holes with a diameter of about 2-3 mm are perforated with a pitch of 4: 1¢¢ (four holes per inch, every 6.35 mm). Winding of spirals onto blocks is carried out using semi-automatic machines type 52 E (Renz, Germany) or manually.

When fastening book blocks with wire or plastic combs, a more sparse and coarse perforation is usually used with a pitch of 3: 1¢¢ and 2: 1¢¢, and when fastening with wire combs, the holes are made square, and when fastening with plastic combs - rectangular, narrower and longer . Manufacturers offer fastening combs of various sizes depending on the thickness of the book blocks being fastened (Table 5.4).

Inserting wire combs into a prepared book block and compressing them to form closed rings that completely cover the edge of the spine zone are carried out on Renz-Autobind semi-automatic machines, the hourly productivity of which is about 1 thousand A4 blocks, or on small-sized desktop devices with manual drive of actuators. Manufacturers supply plastic combs twisted into tubes, so when they are inserted into perforation holes in Attacombo Super type machines (Attalus International Corporation), the combs unwind so that their teeth can enter the perforation holes. The compression of plastic combs occurs due to the restoration of highly elastic deformation of the main component of the polymer.

The advantages of methods for fastening blocks with spirals and combs include their relative simplicity of technology, which does not require highly qualified maintenance, the possibility of their use in small enterprises and offices, full (180°) opening of book-type products, the possibility of using covers of various designs (Fig. 5.23 ).

The disadvantage of methods for fastening blocks with spirals and combs is the use of part of the spine, which somewhat reduces the percentage of paper used.

Bonding with spirals and combs is used in the production of wall calendars, diaries, various catalogs, music and general notebooks, notebooks, and abroad in the production of some textbooks.

Fastening blocks with screws and rivets. When fastening blocks with screws and rivets, two or three through holes with a diameter equal to the size of the bushing or shaped nut of the fastener are punched or drilled in the root zone. Fasteners are inserted into the finished holes by hand, after which the rivets are pressed with a hammer or in a lever and screw press. When using threaded fasteners, the block is secured with a screwdriver or, if there is a notch on the screw head, by hand.

This type of binding is used primarily in the production of albums for various purposes and folders with paper for explanatory notes for theses and projects. Good opening of albums is ensured by the use of fabric hinges connecting the sheets of the block with the spine strips of cardboard.

Fastening blocks with locks and clips. The fastening of blocks consisting of individual sheets can be done using spring locks, which are securely fastened with rivets to welded plastic binding covers. A spring lock can have from 4 to 6 pairs of half rings, which tightly fit into rings in the finished product. In other types of locks, the sheets of the block are tightly compressed along the spine by a spring-loaded bar, the position of which is fixed by a lever and a latch. The first option of locking involves perforating round holes with a diameter of about 4 mm in the root zone of the block. In the finished product, the sheets of the block are fastened in the same way as when fastening with combs, but the number of elements holding the block together is approximately an order of magnitude smaller.

When using spring-loaded locks, the sheets of the block are kept from falling out of the clamp by frictional forces, which depend on the pretension of the spring, the thickness of the block, the smoothness of the paper and the position of the sheet in the block. If the block or clamping device is handled carelessly, the sheets of the block may fall out, so this type of block fastening is used in cases where the order in which the block is assembled does not matter: in the production of white goods, for storing various documents, etc. The advantage of the spring-loaded method of fastening blocks The main advantage is that the block does not require any preparatory operation, and the main disadvantage is the high cost of binding covers with built-in spring locks.

At its core, fastening blocks with clips (springy U-shaped fastening elements with “wings” converging at a certain angle) is similar to fastening blocks with locks with a spring-loaded bar: in both options, the sheets of the block are held by friction forces. The difference is that the clips are usually independent fasteners. When using clips, they must be selected according to the determining size, according to the thickness of the block with a small margin, and the blanks must be cut in accordance with the height of the blocks.

As an independent type of fastening, this method is used mainly for storing archival documents. Sometimes fastening with clips is used in the production of reference books and catalogs of products in rapidly developing industries, since this type of fastening makes it possible to easily supplement the block with sheets or replace some of its sheets with new ones.

51 52 53 54 55 56 57 58 59 ..

STACKING NOTEBOOKS INTO A BLOCK

Sewing notebook blocks with threads

Sewing with threads by hand is most often done using notebooks. It can be done on cords, braids, or binding gauze.

Sewing on cords(Fig. 43) is the most ancient method. The notebooks of the completed block are pushed onto the spine and clamped in a wooden vice. Grooves are cut across the spine, the depth of which should be equal to the width of the cord. Slots are made on the upper edge and lower part of the spine to facilitate the removal and insertion of a needle and thread into the notebook. After sawing, the grooves are straightened with a file.

The first and last notebooks, as well as the endpaper, are not sawed through, but set aside, and only after sawing through the remaining notebooks can they be attached to the block.

The block is removed from the vice and sewing begins on the machine, onto which the cords are pulled in accordance with the placement of the grooves on the notebooks. (The design of the stitching machine is presented in Chapter 3, § 4.)

Sewing begins with the last notebook. The notebook is placed on the table behind the cords so that the cords are located opposite the slots. Place your left hand in the slot of the notebook, and with your right hand insert a needle and thread into the slot from the side of the head. Grab the needle with your left hand and pull the thread inward, leaving a small end outside. Then the needle is taken out, passing it on the left side of the cord, and again inserted into the notebook on the right side of it. Sew the notebook to the rest of the cords in the same way.

Having pulled the thread out through the bottom slot, stretch it so that it fits tightly to the cords, and the stitches inside the notebook are located exactly along the fold. Place a second one on top of the stitched notebook and stitch it in the same way as the first. Upon exiting the head slot of the second notebook, the thread is pulled and tied to the remaining end of the first notebook. The remaining notebooks are sewn using the same techniques, passing the thread at the transition point to the next notebook under the thread stitch formed when sewing the two previous notebooks. To speed up the sewing process, you can stitch two notebooks at a time (Fig. 43, b), but this reduces the number of stitches.

The stitched notebooks along with the cord are removed from the machine and they begin to unravel the cord, which is done using a “tatter.” The cord is passed through the cutout of the “tatter” and rubbed with the blunt side of a knife until all the fibers are aligned in the form of a thin flat brush, since a poorly frayed cord is noticeable after covering the book with the spine.

Sewing on gauze or braid used more often than sewing on cords. If the root material is narrow, for example braid (Fig. 44, a), then an external stitch can sheathe this material, and if it is wide (gauze), it can be stitched (Fig. 44, b).

The ribbons for the braid are cut in accordance with the thickness and format of the book. Books should be sewn on at least three braids. Such a book will open well and be very durable.

Stitching notebooks is done in the same way as with cords, with thread covering each braid, the only difference being that the needle inside the notebook is turned rather than passed through the cuts.

When tying the ends of the threads, it is recommended to use the following technique: the end of the used thread outside the braid is connected to the end of the new thread and these ends are bent around the needle. Then the needle is turned around clockwise, forming a loop through which the needle with a new thread is pulled and pulled into a knot that does not untie.

When sewing on braids, the following rules must be observed:

Use threads that match the thickness of the notebooks;

tie the ends of the threads firmly with a non-untie knot;

The knot of interconnected threads should be located only on the outside, on the braid;

Sew notebooks exactly in the middle of the fold;

Firmly fasten the thread after finishing sewing the book;

Punctures with a needle should pass 1-2 mm from the edges of the ribbons;

After sewing each notebook, the thread should be well stretched;

The sheets of the notebook and the notebooks themselves must be aligned on the head and spine;

To level the books, you need to lay boards from the front edges.

After sewing, the ends of the ribbons are glued to the endpaper, for which they are trimmed, smeared with glue and rubbed tightly with a bone. The endpaper can be greased according to the template to the size of the ends of the braid and the ends can also be glued, tightly rubbing and pulling them with a bone. The more neatly the ends of the ribbons are glued, the more beautifully they will protrude from under the endpaper in the finished book and the stronger the binding will be.

When sewing by hand, you can use both cotton and nylon threads.

Analog proofing (raster proofing)- a color proof made from color-separated rasterized photographic forms (usually for offset and letterpress printing) before printing the publication.

Creasing- the process of applying straight grooves - bigs.

Brochure- a book edition of 6 to 48 pages in soft cover in the form of several bound and stapled sheets of printed material.

Paper- material in the form of a thin layer (up to 400 microns), consisting of pre-ground plant or synthetic fibers, randomly intertwined and interconnected by hydrogen bonds and a sizing agent. Paper is formed by deposition on a continuously moving mesh of a paper-making machine from a fibrous suspension diluted with up to 90% water. When paper is formed, the front and mesh sides are formed, which may differ in their properties.

Layout- 1) the process of forming a publication page; 2) a print sent for proofreading.

Lashing-sewing-cutting machine/unit (saddle stitcher)- a line (unit) designed for the production of brochures and magazines with an insert along with the cover, stitching them with wire along the fold with bending the legs of the staples into the block and trimming on three sides.

Auxiliary printing materials- printing materials that participate in the technological process and contribute to the production of the publication, but are not directly included in the publication, for example, photographic film, form materials, offset rubber-fabric plates, etc.

Selective varnishing- varnishing of the print not over the entire surface, but only in its individual areas. For selective varnishing, screen, letterpress (flexographic) or offset printing forms are used.

Reversal (reverse printing, reversal)- printing the background with black or colored inks, in which only the text remains unprinted. Used as a design technique for advertising brochures, magazine pages, etc.

Die cutting- cutting out, using a sharpened stamp, labels or other products or configurations, usually occupying the entire area of ​​the sheet. It is carried out on a small pack of sheets. Often die cutting is done using individual screws in the form of strips or squares into which a stack of prints is pre-cut.

Grayscale- levels of gray: from white to deep black.

Color tone gradation- different levels of one color tone: from white or black to the most saturated.

Two-side print- printing on two sides of paper (cardboard, film, etc.) in one pass of the sheet in a printing machine.

Densitometer- a device designed to measure optical densities by reflection (on prints and photographs) and by transmission of light (on slides, negatives and transparencies).

Dispersion varnish- water-based varnish, does not affect the color characteristics of the print.

Prepress equipment- is intended to carry out the processes of preparing a publication for printing up to and including the production of the printing form.

Pre-press processes- all stages of printing technology associated with preparing the publication for printing (typesetting, color separation, text and image processing, layout of the publication’s pages, installation and layout of the pages on the printed sheet) up to and including the production of the printing plate.

Cardboard- dense wood fiber material with a thickness of 0.3 mm. Paper with a density of more than 250 g/m2 is considered to be cardboard, unless otherwise specifically stated.

Cassette folding machine- in which folding of a paper sheet is carried out using a cassette that guides the sheet at the point of future folding into a rotating pair of rollers, forming a fold of the sheet.

Laminating- connection (gluing) of two different materials (for example, aluminum foil and paper).

Classification of printed paper- grouping different types of paper according to the following criteria: 1) by printing method (printing, offset, gravure printing, etc.); 2) by type of printed product (newspaper, book and magazine, illustration, cartographic, etc.); 3) by product type (sheet or roll); 4) by manufacturing method (coated, uncoated, with watermarks, etc.); 5) according to the finishing method (machine smooth, glazed, embossed, etc.). Each classification group may have several grades of paper, which differ from each other by individual indicators and are additionally marked with letters and numbers.

Adhesive seamless fastening- fastening the sheets of the book block along the spine with glue.

Combined folding machine- in which possible folds are formed both with the help of cassettes and knives installed in various folding devices and sections of the machine.

Completing the block with a tab- compiling a book block by inserting notebooks into one another in a certain sequence. Used in the production of small-volume magazines and brochures (up to 96 pages).

Equipping the block with a cape- compiling a book block by throwing notebooks one on top of another in a certain sequence. Used in the production of small-volume magazines and brochures (up to 96 pages).

Completing the block with a selection- compiling a book block of a publication from notebooks or separate sheets arranged one after the other. Widely used in the production of book publications.

Completing the book block- arrangement of a book block from notebooks (sheets) and other component parts with an insert (cape) or selection.

Embossing (embossing)- obtaining a multi-level relief image without paint and foil by compressing a section of the binding cover or postcard between the heated stamp and counter-stamp (respectively, the punch and the matrix). It is performed in special printing presses or in crucible printing machines. This is an effective technique for decorating binding covers and advertising publications on thin cardboard or thick paper, sometimes using foil.

Control dies- dies for checking the established standards for ink supply during printing.

Control print- an impression taken from a printing machine during printing of an edition for evaluation and control of print quality. The control print is evaluated by the printer or other employee of the enterprise, and in some cases also by the customer.

Copy frame- a device consisting of a table and a glass lid. The table can be vacuum. The copy frame is used for exposing photosensitive sheet materials. The radiation source is located relative to the table in such a way that the maximum amount of radiation falls on the table.

Copy layer- a light-sensitive layer containing light-sensitive substances (diazo compounds, gelatin with alkali metal dichromate, etc.); used in the manufacture of printing forms. Photopolymers are also used as a copy layer.

Spine- 1) the edge of the book block, the place where all the technological elements of the book are fastened (notebooks, gauze, captal, strap, etc.); 2) micro-irregularities on the surface of offset plates after graining (“coarse spine” - an offset plate with relatively large micro-irregularities).

Paintprint- 1) an image (text, illustration, etc.) obtained as a result of each contact of a sheet of printed material with a printing form; 2) a sheet of one of the main standard formats printed on one side with one ink: 60x90, 70x100, 60x84, 70x90, 75x90, 70x108, 84x108 cm. The ink prints evaluate the productivity of printing machines, printing departments, and the volume of production of the enterprise.

Paint run- 1) receiving a print from only one printing plate in a printing machine; 2) a unit of productivity of printing equipment, equal to each print of ink when the printed material comes into contact with the printing plate or the surface of the offset cylinder. The number of paint runs per one sheet pass corresponds to the color quality of the printing machine. With single-sided single-color printing, there is one ink pass in one sheet feeder (in all other cases, the number of ink runs exceeds the number of sheet feeders), when printing on a four-color printing machine with a sheet-turning device, operating according to both the 4+0 and 2+2 schemes, there are four ink passers in one sheet feeder.

Varnish- a solution of film-forming substances in organic solvents or water, creating a transparent, uniform film after hardening. Designed for finishing printed products. Varnish is applied to prints in special varnishing machines, as well as in the varnishing sections of printing machines. Water-soluble varnishes are applied to prints using the dampening apparatus of an offset printing machine.

Varnishing- improving the surface of a print or paper by applying a layer of varnish.

Lamination- refining paper by applying a polymer to its surface using the melt method to impart gas, steam, water resistance and other special properties to the material. Widely used in the production of packaging materials for food packaging and in the finishing of printed materials. Lamination is a common case of film pressing, so the term “lamination” is often identified with the concept of film pressing and vice versa.

Screen lineature (screen frequency)- a parameter characterizing the raster structure by the number of lines per unit length. Raster circulation range: 20, 24, 30, 34, 36, 40, 44, 48, 54, 60, 70, 80, 100, 120, 150, 160 lines/cm. Due to the development of electronic screening, the number of lines in one centimeter can be fractional, for example, 39.5; 59.5. In computer (electronic) screening, the units of measurement of lineature in lines/inch or mm -1 are more often used, for example 150 lines/inch or 8 mm -1 .

Sheetfed printing machine- a machine from a group of printing machines designed for printing single-color or multicolor prints of small and medium runs on separate sheets of the printed material - paper, cardboard, tin, etc. The printed material is fed and output in the form of sheets. Sheet-fed printing machines differ in printing methods (for letterpress, offset, intaglio, etc.), in the format of the printed sheet, color, design features of the printing section (three-cylinder, five-cylinder, planetary), in the type of printing form (rotary, flat-bed), in modular structure (linear, sectional, tower type), etc.

Collating machine- a machine consisting of a certain number of feeders and a conveyor on which a publishing block is assembled from individual notebooks. A block of notebooks can be completed with a cover, an insert or a selection, depending on the technology requirements. Although the machine is called a collating machine, it always picks up notebooks. It is called collating because it selects printed sheets folded into notebooks. Not to be confused with a leaf picker (colllator).

Leaf picker (colllator)- a machine of tower or horizontal linear construction, consisting of a certain number of trays, from which sheets are fed one at a time and a publishing block is selected. Sheet pickers, as a rule, are office machines and are of little benefit for mass production of printed products in terms of reliability.

Sheet runner- each passage of a printed sheet through a printing machine, regardless of the number of inks applied to it. Based on this indicator, the loading of printing machines is calculated and order processing schedules are drawn up.

Slur- a printing defect in the form of small, visually noticeable traces of paint on the print, printed elements that are not on the photo form, or the absence of image elements. Usually, marks occur when foreign particles (pieces of paper, dust, dried paint, etc.) get on the printing plate or the offset rubber-fabric plate. As a rule, you get rid of marks by removing them from the surface of the printing plate or offset cylinder.

Paper weight- the mass of a unit area of ​​paper, determined by the standard method and expressed in grams per 1 m 2. The correct use of the term is: “the weight of 1 m 2 of paper is 100 g,” although it is often found that “the weight of paper is 100 g/m 2.”

CMYK model- a model that describes color in the space coordinates of subtractive paint synthesis by mixing triadic printing inks: C - Cyan (blue); M - Magenta (purple); Y - Yellow; as well as black - K - Key color (according to one version) or black - K (according to another version). Thus, the RGB and CMYK models are related to each other, but their mutual transitions (conversion) occur with certain losses. This necessitates complex calibrations of all the hardware of publishing computer systems required to work with color: scanner, monitor, output device. It is also necessary to normalize the printing process (calibration) of the printing machine, which performs the final stage in creating a color image on the print.

Installation of photoforms- placement of text illustrative transparencies or negatives on a transparent mounting base (astralon) in accordance with the layout of the publication, diagram, original, standard, etc. Typically, installation of photo forms is carried out on the mounting table, as a rule, using a mounting measuring grid made on a transparent base and rulers with pins for the pin register system.

Moire- visible, periodically repeating spots (an extraneous pattern in the form of a grid), stripes or lines that appear when two or more periodic planar structures (raster images) are superimposed. Moire can occur when choosing the wrong raster rotation angle, when reproducing raster images (prints), or when printing on material with a regular structure on the surface. Sometimes it can appear on part of the image during rasterization, if this part has a periodic structure.

Font style- a graphic design of a font included in one typeface. They are classified: by the width of the glasses (normal, narrow, wide), by the inclination of the glasses (straight, italic), by the saturation of the glasses (light, bold, bold). Misregistration of paints (mismatch of paints, misregistration) - shift of images,

Mismatched paints- shift of images made with different printing inks on a print during the synthesis of a multicolor image; occurs due to poor-quality registration, adjustment of printing forms or the manufacture of color-separated photo forms themselves, as well as deformation of photo forms, offset printing forms, installation defects, inaccuracy in feeding and/or transfer of sheets of paper, deformation of paper when its humidity changes during the printing process, and other reasons.

Thread sewing machine (NSHA)- a thread sewing machine that binds notebooks into a book block with automatic individual feeding of notebooks into it by feeder without direct human participation in each cycle of the machine.

Numbering- printing, as a rule, using special devices - numberers, changing numbers on prints (for example, on securities, forms, tickets, numbered publications, etc.).

Cover- a soft paper illustrated or text cover (covering made of durable paper or thin cardboard) of a publication, which, like a binding cover, protects its pages and the block as a whole from destruction and contamination. The cover is also an element of the external design of the publication, performing certain artistic functions.

Single color printing- printing reproduction of the original using one printing ink of any color (most often black).

Single blade cutting machine- a machine for trimming and cutting sheets of paper, cardboard, prints and binding fabrics in a stack with one knife.

Single-sided printing- printing on only one side of the printed material, for example, labels, posters, advertisements, wallpaper, etc. As a rule, one-sided printing is carried out on materials with different surface characteristics of the sides, for example, labels are printed on label paper, in which one side is polished , and the other, with which the label is glued to the product, is rough.

Optical density- a measure of light transmission for transparent objects and reflection for opaque ones. Optical density is quantified as the decimal logarithm of the reciprocal of the transmittance (reflectance). In printing they are used to evaluate publishing originals, intermediate images (photoforms) and prints.

Original- text and illustration material that has undergone editorial and publishing processing and is intended for reproduction by printing means. Fine originals, by the nature of the elements they contain, are line or halftone, black and white or color; by technique - drawings, photographs, printing or computer graphics. Text originals, depending on the execution, are divided into typewritten, printed for reprinting without changes, printed for reprinting with changes, encoded (on magnetic or optical media), reproduced original layouts (ROM), handwritten. Author's original (this is text and illustration material prepared by the author (authors) for transfer to the publishing house for preparation for publication.

Basic printing materials- printing materials that are involved in the technological process of production of the publication and are directly included in the publication. For example: paper, paints, binding material, threads, wire, glue, etc.

Finishing processes- processes of additional processing of printed products to improve their appearance, improve quality and strength, for example, varnishing, creasing, embossing, etc.

Imprint- an image of text, illustration, etc., which is obtained during the printing process using printing means on paper or other printed material.

Offset rubber-fabric plate- a multilayer composition of layers of fabric and rubber with a one-sided rubber coating, which is covered with the offset cylinder of printing machines. This coating takes the printing ink from the printing elements of the printing plate and transfers it to the paper.

Perforation- 1) a system of holes or notches in sheet or roll material (most often located in a line), ensuring easy tearing of the material; 2) a system of holes, for example, in endless forms, designed for transporting paper in printing devices. Perforation is created using special knives, disks, and rulers.

Punching- the process of applying perforation using special devices - perforators.

Printing ink- a heterogeneous colloidal system consisting of highly dispersed particles of pigments (varnish pigments), evenly distributed and stabilized in the liquid phase of the binder. A number of additional components are added to the printing ink to improve its printing properties or give the ink special properties, for example, color changes under the influence of certain radiation or chemical solutions.

Printable form- a plate, slab, cylinder, mesh used to form and save an image in the form of printing elements and white space elements. The ink from the printing elements is transferred to the printed material or intermediate link, for example, an offset cylinder. Printing plates are made from different materials depending on the technology and printing method.

Printing machines- machines that perform the printing process using one of the printing methods. Printing machines are classified: 1) according to printing paper - into roll and sheet; 2) by design - crucible, flat-bed and rotary; 3) by the number of colors - one-, two-, and multi-color; 4) by printing method - printing (letterpress), offset, intaglio printing, screen printing and other special types of printing; 5) by type of product - into universal and specialized (newspaper, book and magazine, for printing on cardboard or tin); 6) by format - small format (up to 50x70 cm), medium format (from 50x70 to 70x100 cm) and large format (more than 70x100 cm).

Seal- the process of obtaining an image of the original on a print by applying a paint layer or layers of different paints to the printed material using printing methods.

Die- 1) part of a printing form with a continuous printing surface or part of a print with a continuous printed surface; 2) continuous coating of the surface of the printed material with printing ink, when the relative area of ​​​​the printed elements (100% (Srel = 100).

Subscription list- a print printed in a printing machine at the end of all preparatory technological operations, which fully complies with the requirements of the order. It is approved by the press master, the customer’s representative or other responsible person and is the standard for printing the edition.

Paper cutting- processing of sheet paper or cardboard by cutting to create two mutually perpendicular “true” sides and give printed sheets precise dimensions. Paper cutting is carried out on single-knife paper-cutting machines on four sides, and if the edges are of good quality, on both sides at right angles. The trimmed corner is called the “correct” corner and is marked on the racks of printed paper.

Printing- a branch of technology, a set of technical means and technological methods used to obtain a large number of identical copies (reproductions) of the original that have undergone editorial preparation.

Band- the printed area of ​​the page of any publication on which the typing of text (illustrations) is placed. There are end, row, initial, illustrative, and tabular stripes.

Registration crosses- marks in the form of thin short lines intersecting at right angles, applied to the margins of the original, photo forms or their montages. Registration crosses are used to control the registration of inks on a print during printing and to evaluate the accuracy of the register after printing. On each color-separated photo plate (montage of photo plates), registration crosses are present in the same place. On prints, registration crosses are located in the trim area. When finishing printed products, they are removed.

Gluing- 1) connecting the flyleaf or fractional part of the printed sheet with the outer part of the notebook; 2) a sheet with an illustration or a fractional part of a printed sheet, glued with a narrow strip to the spine of the outer page of the notebook. Glues can be attached directly to the outer page of the notebook (option - with edging) and to the rod (glued to the rod) with an indentation from the spine fold of the notebook, as well as to the mat.

Film pressing- the process of applying a transparent polymer film with or without a layer of adhesive to one or both sides of a print, paper or cardboard.

Wire sewing machine- a machine designed for fastening notebooks and sheets of book blocks, brochures, notepads, calendars, etc. with wire staples. Machines differ in the degree of automation, the number of simultaneously applied staples fastening notebooks or sheets.

U-turn- two adjacent pages of the open edition, even and odd, left and right.

Screening- conversion of halftone and line images into microline images using a raster (in reproduction cameras and contact-copying machines) or using hardware and software (in publishing systems).

Cutter- a device consisting of a table and a cutting tool (reciprocating knife, disk) and intended for cutting films, photographic films, paper, cardboard and other sheet or roll materials.

Risograph- a screen printing machine that uses a screen printing form that is made in the machine itself using laser technology immediately before printing.

Risography- a proprietary name for a rotary screen printing method using a printing plate made by laser-burning micro-holes in the plate material to form printing elements.

Roll printing machine- a rotary printing machine for printing on a continuous web of printed material unwinding from a roll. The final product can be in the form of notebooks or sheets, or in the form of a canvas that is rolled into a roll.

Full varnishing- varnishing the entire surface of the printed sheet, as opposed to selective varnishing.

Offset printing method- indirect (“indirect”) flat printing, in which printing ink from a printing plate for any printing method (high, flat, intaglio) is transferred to the printed material through an intermediate offset cylinder.

Screen printing method (silk-screen printing)- image transmission using a printing form, which is a mesh (stencil), through the cells of the printing elements of which, using a squeegee, printing ink is pressed. There are variations of the method: classic screen printing and rotary printing (see also Risography). The image on the printed form is mirrored.

Imposition of stripes- placement of publication pages on the mounting and printing plate, ensuring after folding the prints the required arrangement of pages in notebooks and in the publication.

Circulation- the total number of copies of a printed publication of one title.

Edition print- an imprint obtained during printing of a publication. Using circulation prints, they control the quality of printing, comparing them with the signature sheet (standard print), analyzing operational control scales, etc.

Title page- the first output page of the publication, which contains basic information about it. The title page is placed on the right, odd half of the first spread. A double-page title page is used in multi-volume editions (on the left side there is a counter-title relating to the entire publication, on the right side there is the title of this volume).

Trapping- overlapping of contours during reversal, overlap of contours (overlapping of image elements along the contour - a combination of scales) of the slide and negative of the same color image in the process of manufacturing photoforms, which ensures the coincidence of the contours on the print with an acceptable misregistration of paints in the process of multicolor printing. It is used when printing colored text on a background of a different color or reversed on a multi-color background to avoid white gaps between the text and the background. A program in publishing systems used to carry out the procedure of overlapping contours when processing images and preparing them for publication is called a trapping program.

Triad of printing inks- a set of printing inks (magenta, yellow, cyan), intended for process printing of color images. In addition to color inks, the triad of printing inks also includes black ink. The combination of spectral characteristics is the characteristic and most important feature of the triad printing inks.

fold- place where the sheet is folded. Folds are created during the folding process.

Folding- bending, folding a print (or paper sheet) into a notebook.

Photoform- a slide or negative (on a transparent basis), prepared for copying onto plate material in the manufacture of a printing plate.

Chromalin- analogue (raster) color proof by Du Pont from color-separated raster photo forms, which has become synonymous with similar color proofs created by other companies.

Color correction- changing the color characteristics of the reproduced image in the process of preparing it for printing and during printing.

Color separation- the process of dividing a color image of the original using light filters or selective lighting sources into separate single-color images of equal scale. Color separation is carried out using scanners, computer systems, electronic color separators-color correctors (ECC) and reproduction cameras. Color separation can also be done manually when creating color layouts for line images.

Color separated printing plates- a set of printing forms for obtaining multicolor images on a print. Printing forms are produced by copying (exposing) color separated photo plates onto the plate material or directly onto the plate material by scanning. Sequential printing with the appropriate printing ink from each color-separated printing plate onto one sheet of paper results in a combined multicolor image (imprint).

Color proof- obtaining a control color image on a tangible medium or on the color screen of a video terminal device. There are analogue (raster), digital (halftone) and screen proofing.

Digital printing- technology for producing prints in a printing press using a variable printing form, changes in which are controlled by the computer of the publishing system at each cycle. This type of technique is used for small-circulation advertising or commercial publications, which must be modified during the production process. Some machines allow changes to be made after even one copy has been printed.

Digital proof- a color proof on which a multicolor image does not have a printing raster structure. A halftone (digital) color proof can be obtained, for example, on color printers in publishing systems.

Sewing- a method of fastening the notebooks of the publication into a block. Depending on the material used, there are two sewing methods: wire and thread. Depending on the number of work cycles used to completely stitch notebooks into a block, two sewing methods are distinguished: block-by-block (the entire block is stitched in one cycle) and notebook (each notebook is stitched separately).

Sewing with notebook threads- sequential sewing of notebooks along the spine of a block completed with a selection of thread stitches. They are used for long-term book editions (hardcover), although the durability of such editions is less than those bound on spine material.

Sewing with wire- tetrad sewing or stitching, saddle stitching or saddle stitching, when wire is used for sewing.