Hardcover book processing operations - Causes of shell warping

Fourth, the book shell warping causes and solutions

The quality of hardcover books and magazines is as good as the quality of books and magazines. The second is to see if the appearance of bookbinding processing and design books is beautiful and firm and durable.

Hardcover bookcase hair is the quality of the appearance of hardcover books.

1. The reason why the book shell is curled.

(1) Since there is no processing plant for binding books and magazines, materials such as cardboard cannot meet the required requirements. The production of cardboard horizontal and corrugated with the use of adhesives, water size, degree of drying, storage equipment and conditions, etc. can not be done by the requirements of the book processing plant. This brings great difficulties to bookbinding and processing, and it is difficult to guarantee the smooth and beautiful effect of the hardcover book case.

(2) Due to the different climate and dry humidity in different regions or the limited conditions of scientific management of raw materials, many book binding and binding workshops have poor warehouse conditions for storing cardboard and cover materials. If the temperature is improper, the ventilation equipment is not good, and the drying and humidity are not in conformity. The requirements for storage of cardboard, cardboard storage time is too short, etc. will affect the quality of the book shell after production.

(3) During processing, proper processing methods and the viscosity of the viscous material cannot be selected based on the quality of the existing raw materials, so that the finished book case is deformed and warped.

It can be seen that the main reason for the curling of the book shell is the degree of moisture evaporation and drying and the influence of the method. Therefore, in terms of storage materials, processing methods, etc., analysis and solution should be focused on moisture and drying degree and methods.

2. The solution of the bookcase hairpin. For a printing factory or a binding factory, in order to solve the issue of warpage (mainly upward warpage) of the hardcover book case, the processing method should be the main method, and the others should be supplemented, and the materials should be properly grasped.

(1) hot-press drying. Before processing, the original sheet is first dried by hot-pressing (heat pressing temperature is generally about 70°C), so that the moisture in the fiber holes inside the cardboard is evaporated as soon as possible. It can also make the roughness of the rough surface of the board surface smooth and smooth after a certain pressure. After the book shell is made into a paste, it can be hot pressed again to remove the moisture of the adhesive. In this way, after two hot pressing (or non-heating pressure), the surface of the book case is flat and compacted, and the possibility of warping can be reduced.

(2) Select the appropriate adhesive. In the cover of the paste to use less moisture content, bonding ability of the adhesive, commonly used in several adhesives bone glue moisture is small, fast drying, more advantages than other adhesives, it is suitable for paste hardcover book shell .

(3) Deal with the book cover and cover pull. Whether it is a paste book cover or a lining, the pulling force of the cover in principle should exceed the tension of the cover in the processing, so that the surface of the book cover can not be upward (outwardly) warped after the sleeve is processed. Therefore, the cover of general hardcover books is glued when glue is used, and flour paste is used when the liner is lining up. When processing the big picture book, both the cover paste and the cover lining also use glue, and then add a layer of lining paper between the cover and the backing paper (the paste can be used when sticking the lining paper), so that the cover part is one more layer. Adhesive, in order to produce a strong pull inwards, control the upward force of the cover. At the same time, horizontal stripe should be appropriate in the selection of the cover material, and the possibility of warping the stripe is less.

(4) 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 (minimum of not less than 12h). After the book is completely dry naturally, the finished product is inspected, sealed or packaged.