The relationship between the selection of the book cover and the quality of the binding after printing

There are many books in the selection of the cover because they did not take into account the difficulties and effects of processing, resulting in a variety of quality issues, the following list some situations, please analyze.

1. Cover paper and book paper thickness difference

In order to decorate the appearance of the books and improve the binding effect of books, there are many book books whose cover thickness is different from that of the book block inner paper. After the books are bound into a book, the pull strength of the books is too different. After the wireless glue is set, the cover is lifted. The first page of the book block was broken to expose the rubber base or pull off the page, resulting in defective products, which made publishers and processors inconsistent. When this type of product is encountered, a single lining or ring lining with a proper amount can be added between the two, and the above problems can be solved by evenly distributing the pulling force. However, publishers often do not consider this aspect; in addition, the cover is indented. At that time, increasing the pressure can also solve this problem, but it is prone to crushing and crushing.

2. Cover design and improper material selection caused the crease to break

Now that the thickness of book covers is increasing, the amount of 200g/m2 paper or 250g/m2 paperboard is weighed, and the front opening process is added to the design. The result is: (1) the front mouth creases break, and the print breaks. Expose the bottom of the paper and destroy the quality of the books; (2) When the amount of paper is more than 200g/m2, the front cover of the front cover is very difficult to bind, the machine cannot accurately indent the mark, and the hand is scratched and the quality cannot be guaranteed. It also caused the appearance of substandard products.

3. Cover length shorter than book block length causes dirty books

Most of the cover length of the publishing unit when designing the cover is always about 7mm shorter than the length of the book block. When the wireless adhesive is coated with the cover of the back cover, the glue at one end (hair side) of the book is exposed and exposed when the cover is transferred. The glue remains on the conveyor belt or the lower board to contaminate the book. Now when the publishing house designs the cover, it is basically double-up with 32 pages and the two cover designs do not leave a copy at the convergence point. There is no room for the entire cover. I do not know if this approach is to save paper, or do not understand the binding process. If the size of the length of the book is given at design time (more than 7mm per foot), the phenomenon of dirty belts and dirty books can be completely solved, but this problem has been ignored for several years.

4. Design patterns leave no room for processing

Some American editors designed some layouts with large differences in color on the cover. They did not consider the difficulties of binding, nor did they understand the national quality standards of the bound pages after printing, resulting in less than expected results when binding. For example: to bind a paperback book (radio glue binding) with a thickness of 12mm, the spine part is designed to have black characters on a white background, and the cover and back cover are full-size black-on-white, and the cover must not be exposed during processing. The spine cannot be blacked out. This requirement is too difficult. According to the national CY/T288-1999 binding quality requirements and inspection methods - the provisions of paperback 3,4,5: "shuzi character translation error is based on the back centerline of the book, book back thickness of 10mm and 10mm in the finished book, spine word Translational tolerance ≤1.Omm; book back thickness greater than 20mm and less than or equal to 30mm of the finished book, spine word translation tolerance is 2.5mm”; “The spine word skew tolerance is less than the tolerance of spine word translation 0.5mm” . According to the provisions of the thickness of 12mm book back tolerance should be ≤ 1.2mm, but such a black and white design, for processors "black not white, white does not reveal black" requirements, how can we achieve it?

5. "Blood Book" increases the difficulty of binding and processing

Now there is a book called "Blood Exposure Book." After the book is bound and the finished product is cut, it is required that the frame and line marks are exposed on the incision, and a straight line pattern is formed on the cut portion. After this process has been folded, glued, matched, packaged, cut, the exposed prints are neatly processed in a straight line.