With the sustained and rapid development of the national economy, the demand for various types of specialized books continues to increase, and the number of books published by various publishers has increased substantially to the provincial book quality inspection stations. The number of test products participating in the quality assessment increases at an annual rate of about 10%. At the end of 2004, more than 6,500 varieties of glue-binding products participated in the testing.
Judging from the overall design of the book, the previous situation in which only emphasis was placed on prepress and printing and light binding processing has changed a lot. People in the industry generally realize that for a high-quality book, not only good, plate-making technology, exquisite printing effects, but also a fine-grained appearance, can be complemented with its overall design and book content, and it can be even longer. The use and preservation of value. In recent years, more and more books have been printed with different grammage papers, plastic film printings, and varnishes and special inks to decorate the book synthesis situation recommended by publishers and various manufacturers and postpress processing. From the test results of the book, it is realized by prepress and printing in the process of processing. Basically can receive the ideal results. And for the post-press processing due to the current selection of materials? 9. The bad quality dike is the bad garden, the bad garden, the dipper, the dipper, the dipper, the south crab, the crab (5), and the oil field.EVA glue, to date has not yet seen one with other types The company's printing and post-processing processes for mechanical mass production of adhesive materials are relatively simple. Post-press processing technology is already being used against water because the currently used EVA hot-melt adhesive is suitable for bonding a single type of paper. It can ensure the quality of books and effectively binds a variety of papers and a variety of printing methods. Difficulties. In view of this situation, we will briefly introduce a PUR glue-binding technology that is being used in industrialized countries and hopes to contribute to the research and application of new technologies and materials, and it can be of benefit to promoting the improvement of the overall quality of books.
PUR glue is designed for a variety of different gram printing paper, plastic film coating oil and ink and other materials designed, is a rigid and flexible low-temperature hot melt adhesive. Its main components are polyols with active hydrogen (polyesters, polyethers, etc.), low molecular weight glycols (chain extenders) and addition polymers of isocyanates. The isocyanate base encounters moisture in the air and produces an irreversible textural reaction to form a strong adhesive layer. This is an inherent feature of PUR adhesives. The use of PUR adhesives in the printing industry is gradually promoted with the increasing diversity of printed products. It can bond a variety of materials, including lacquer coatings, UV curing layers, plastic films and coated papers that are not subject to volatilization of various materials. The impact of the material and performance degradation, affect product quality. From the data and samples collected so far, the advantages of books and magazines glued with PUR glue and EVA hot-melt adhesives, which are now widely used, are quite obvious.
According to the EVA hot melt adhesive thickness recommended by this site, EVA hot melt adhesive must reach a certain strength (the thickness of the book block brush glue is different according to the situation of paper and the thickness of the book) and the glue layer is controlled between 0.6 and 2 mm. Under the same conditions, the PUR adhesive layer can reach the same strength as the EVA hot melt adhesive, regardless of the thickness of the paper, regardless of the size of the paper. Normally, the thickness of the PUR adhesive layer is much softer, and the book is very flat after opening, which can greatly improve the reading of the reader. The sense of comfort is a new process to solve the problem of inconsistent books that plagued us for many years.
High temperature resistance and low temperature resistance, strong environmental adaptability
The author collected several friends from Taiwanese printing company to bring back a bound paperback book bound with PUR glue to promote the bookbinding process in the past, and to test the method for checking the booklet of EVA hot melt glue. A contrast experiment will bind a book with PUR glue. Put the book in the refrigerator for more than 4 hours, and then remove the book from the refrigerator as it is. You will not hear the cracking sound of the EVA hot melt binding book after refrigerating. The refrigerator experiment simply detects the adaptability to the low temperature environment that the book may
