Hardcover production line - explanation of common problems (on)

Hardcover books are a more elaborate binding form in book publishing. Compared with paperback books, hardcover books have the advantages of sophisticated materials, strong binding, beautiful decoration, and long-term preservation. Its sophisticated finishing process adds more than 20% additional value to hardcover books. With the development of the publishing industry, hardcover books have shown great market potential. Nowadays, into the bookstore, a wide variety of books appear on the bookshelf before readers, but the most striking book is hardcover. Find out a classic book or a reference book that we often read in weekdays. Most of them are hardcovered, but in the course of use, some hardcover books will also reveal some subtle or even serious quality problems. Although some of these quality issues do not affect consumers' reading and purchasing, they must always be produced with the requirements of a high-quality hardcover book from the perspective of quality management in printing or binding plants.

Recently, with regard to the problems in the production and processing of hardcover books, the reporters of this journal have made in-depth visits to the production line through visits, telephone calls, faxes, and e-mails. Among the interviewees, there are old experts who are still active in the binding field of post-press books, heads of hardcover workshops, and technical backbones that link the production lines. In this edition, Mr. Wang Huaizhu, Mr. Zhang Guoliang, Beijing Hualian Printing Co., Ltd., Zhang Ronggen, director of the binding workshop, Zeng Binghui, the hardcover team leader, and Wei Aiyong, the binding shop of Beijing Aide Jinwen Co., Ltd., and the director of the hardcover workshop at Beijing Xinhua No. 2 Plant Mr. Chen Jianzhang and Ms. Hu Aizhen, Director of the Hardcover Workshop at Henan Xinhua No. 2 Plant, expressed their sincere gratitude.

The processing technology of hardcover books is complex, and each printing or binding factory develops its own process in accordance with the characteristics of its own equipment, processes, and management. Take round-backed hardback book as an example, the main processing flow is as follows: (1) Book block production and processing: folding → matching posts → lock line → flattening → brushing and drying → three-side cutting → rounding and ridge winding → Second brushing → “Three sticky” (paste plug cloth, paste gauze, paste book back paper); (2) Book shell production: blanking → brushing → cover material → edge angle → flattening →Drying; (3) Fitting of book block and book case: Book cover → Press groove → Paste ring → Flattening → Stereotype, etc.

The following interviewees will join with the reporter and take you into the hardcover production and processing line to work with you to solve problems from the frontline.

(A) book block common problems and solutions

1. The thickness of the book block is inconsistent

Printed proofs also require multiple post-processing operations. The folding machine folds into posts and passes directly on the line after being fitted and locked. However, technicians who have many years of practical experience in production have found that the book cores of the upper linkage line are somewhat loose, and the thickness of the book blocks is inconsistent, which causes quality problems in the sequential processing of hardcover books and affects the appearance quality of the books. The problem is manifested in:

(1) The frontal area of ​​the hardcover book easily shows obvious steps.

(2) If the book block is loose, the cutting edge size will be different when cutting. Reflected in the cut part of the book block, it is either small above the large bottom and cut into a horseshoe shape; it is either a small upper bottom or a large wedge cut.

(3) The thickness of the book block is directly related to the quality of the fitting. Although some loose book blocks can still be assembled with the book case, the book case will be opened after the sleeve is closed. Tight phenomenon.

Therefore, in order to eliminate the air between the paper and the paper and make the final finished book neat and tidy, the leveling of the book block is critical.

solution:

(1) When the equipment is put into production for a short period of time

Beijing Hualian Printing Co., Ltd.'s hardcover linkage production line was introduced last year, the equipment is relatively new, only two presses on the linkage line, you can meet the requirements of the book press flat.

(2) When the equipment is put into production for a long time

The practice of Beijing Xinhua No. 2 Factory: The book block was pressed three times. After printing, the signatures on the press are bundled, matched, locked, and then pressed by a press other than the linkage line, and then sent to the glue dryer. Prior to drying, the platen pressure of the linkage line itself is pressed once, and after drying, the three-facet knife is pressed again before cutting. Presses are commonly used equipment in printing plants. The last two presses are the processes for producing the linkage production lines themselves.

The practice of a foreign language printing factory: Put a multi-layered board on top of a book that has been folded well and has been neatly coded, and then put a cement strip on it so that it can be stored for a certain period of time to achieve flattening effect.

2. The size of the finished book block is not standard. Because the book is not firmly positioned due to a certain rule, rules appear to move after cutting many times, so that the size of the cut book block is not standard or inconsistent.
Solution: The positioning is firm, and it is often checked whether the finished size of the book block is qualified to ensure the stability of the quality.
3. There is a knife blade wear or a chipping phenomenon at the corner of the book block.
Solution: Exchange new knives or sharpen them in time.

(B) book shell warping problems and solutions:

The common book case is made of hard cardboard, soft cover, mid-stitch paper, etc. Some large sheets of cardboard are bent after being cut into small pieces; perhaps the quality of a book you bought was very good at the time, but after a while, there will be quality problems such as warpage and arching of the book case. This is mainly due to a combination of factors such as paperboard, adhesives, cover materials, and air humidity.

problem causes:

1. The use of horizontal and vertical stripes on cardboard, the use of adhesives, the size of water, the degree of drying, storage equipment and conditions, etc. cannot be done in accordance with the requirements of the book processor. The binding of the books and magazines brings great difficulties and it is difficult to guarantee the smoothness and beauty of hardcover bookcases.

2. Due to the different climates and dry humidity in different regions or the limited raw materials for scientific management, the dryness and moisture of the binding shop do not meet the requirements for storage board, and the time for storing the paper board is too short, which affects the quality of the book case.

3. During processing, the proper processing method and the viscosity of the binder can not be selected according to the quality of the existing raw materials, so that the finished book shell is deformed and warped.

solution:

1. Choose high quality cardboard. General imported cardboard quality is better, not easily deformed, should be the first choice, and many domestic cardboard quality is very poor, easy to delamination, cutting, the cutting edge is very rough, can observe the phenomenon of paper powder, and cardboard The thickness is also uneven. In order to ensure quality, we must use high-quality homemade cardboard.

2. Hot pressure drying. Before processing, the original sheet is first dried by hot-pressing (hot-pressing temperature is generally about 70°C) to make the moisture of the cardboard evaporate as soon as possible. At the same time, the rough surface of the cardboard surface becomes smooth and smooth after a certain pressure. After the book shell paste is made, it can also be hot pressed once again to remove the moisture from the adhesive. After two hot presses (or no hot pressure), the surface of the book case is flat and compacted to prevent warping.

3. Select the appropriate adhesive. Use a binder with low moisture content and strong binding force when pasting the cover.

4. Handle cover and cover tension. Professor Wang Huaizhu introduced experience that whether the book shell glued or lining, when the processing, in principle, the tension in the cover should exceed the pull force of the cover, so that the surface of the book shell after the sleeve processing without upward (outside) Alice's power. It is generally possible to use the same glue on the cover and the cover lining, and then add a layer of lining paper (bonded with paste) between the cover and the liner so that there is an additional layer of adhesive in the cover so that it can be produced inwards. Strong pull, control the power of the upturned cover. In the selection of cover materials, stripes should be appropriate, and the possibility of warping the stripes is less.

5. Book processing after processing. After the hardcover books and journals have been fitted, lining, and embossing, cross-stitching is stacked on the paper table and it must be smooth without skew. The flattening time is longer (at least 12 hours). After the book is completely dry naturally, the finished product is checked, sealed or packaged.

(to be continued)