In recent years, in the printing industry, the binding quality of books and publications has become a topic of increasing concern for people. People's attention has focused on the relatively backward areas of the bookbinding industry. In book binding, there are many factors that affect the quality of binding, including equipment level, material quality, process technology and management. Among them, adhesives, as indispensable adhesive materials in book binding, play a decisive role in various binding processes. Its performance and quality impact on binding quality and market conditions are common concerns. It is the subject of frequent communication between adhesive manufacturers, printing and binding manufacturers and experts.
First, the market context
The current adhesive market can be summarized with the mainstream products, complete grades, and user needs.
Mainstream Product EVA
There are a wide variety of adhesives used for book binding, and we mainly revolved around the largest amount of hot melt adhesive products in the binding process and have extensive contact with product suppliers and users.
In recent years, the publishing cycle has been continuously shortened, and the printing speed and quality requirements for books and periodicals have continuously increased. In order to meet this requirement, quick-drying synthetic resin adhesives have emerged as the best-in-class binders for bookbinding applications. Synthetic resin EVA hot-melt adhesives are used in high-speed adhesive bonding production lines and stand-alone machines. . The utility model has the advantages of fast drying speed, short curing time, and convenient operation, and because it only needs physical mixing at room temperature, and the liquid is used after heating and melting to a certain degree, the melter device is simple, and the binding speed is also improved. For bookbinding companies, this is less costly and accepted by the majority of users. It is currently the “first glue” in the binding industry.
The survey also showed that there are few domestic animal environmental friendly adhesives, but there is a growing trend. Foreign manufacturers have already established factories in China and invested in the production of adhesive products that meet internationally advocated environmental protection requirements. For example, Shanghai Fengni Davis Adhesives Co., Ltd. is an adhesive manufacturer that mainly produces animal bone glue. Its products are for bookbinding and packaging markets.
Since its inception in 1989, PUR hot melt adhesives have developed rapidly due to their superior adhesiveness and peculiar flexibility, as well as excellent properties such as high temperature resistance and low temperature resistance. In 1995, there were only 28 users in North America. By the end of 2002, it had grown to more than 50. The domestic market has also been opened, but users wait and see more, use less, and are concentrated in the Guangdong region.
The product range is complete
Due to the variety of book binding products and their different grades, the adhesive products also have their own requirements.
The technical level of printing plants will drive the innovation and production of adhesive products. For example, high-end printing companies with a relatively high level of production in the Mainland are concentrated in the coastal areas of Guangdong, and are mainly engaged in fine print. Therefore, the Guangdong coastal area constitutes a major application market for high-grade adhesives, while some large integrated printing companies in the Mainland are also major users of high-grade adhesives.
At this stage, domestic high-end adhesive products for book binding mainly come from some multinational companies and joint ventures. For example, Germany Henkel (Tianjin) International Trade Co., Ltd., National Starch Chemical (Guangdong) Co., Ltd., etc., the annual output is generally about 500 tons, the main users in the country are larger-scale joint venture printing and binding companies, the user range is relatively narrow. However, high-grade adhesive products provide guarantees for the quality of fine books and have a guiding role in the market. Such as Henkel and Martini and Kolbus and many other international printing and binding machinery manufacturers join hands to become the leader in the promotion of PUR adhesives. At the same time, several major manufacturers will also adopt a "backward compatible" approach to produce low-priced products to open up the low-end market and adapt to the needs of customers at different levels.
The mid-to-high end product market is basically controlled by Wuxi Wanli Bonding Materials Factory, which accounts for nearly 30% of the domestic market share and has an annual output of 2,000 tons. At present, Wuxi Wanli has a wide range of domestic sales. Whether it is technological advancement or market share, it represents the highest level of domestic local book binding adhesives production companies. It is a binding glue for domestic bookbinding. Leading company in the field of agent production. Wuxi Wanli, with strong research and development capabilities and production scale, has begun to enter the high-end market and has the ability to produce PUR hot-melt adhesives. However, it adopts a wait-and-see attitude in its promotion and claims that the time is right for a full-scale attack. At the same time, in the market expansion of EVA hot-melt adhesives, it has not stopped its pace and is targeting high-end markets. It is developing new varieties through cooperation and competing with imported products. This "upwardly compatible" approach will undoubtedly expand its product market.
In addition, for the convenience of users, all provinces and cities have bookbinding adhesives manufacturers, and a large number of different grades, mainly for local printing and binding companies. According to Professor Wang Huaizhu, in the Beijing area, there are a certain number of adhesive manufacturers, mainly Zhongqing Adhesive Co., Ltd. in Beijing Yanjiao and Beijing Wensheng Printing Materials Co., Ltd., whose users are located in and around Beijing, and the annual output is 1,000 tons or so.
Adhesives are a large amount of consumables used in book binding, and some printing manufacturers will open up new ways to self-run glue factories. In addition to meeting the needs of their own companies, they also sell adhesives to printing and binding plants. Such as Jinan Huafu Printing Materials Co., Ltd. (affiliated to Shandong Xinhua Printing Factory), its product performance and stability, supply Shandong printing and binding companies. At the same time, we also promoted products to other provinces by training the binding equipment. Some users believe that the biggest advantage of self-produced adhesives is that they can find problems and improve them in a timely manner when using their own adhesives for binding. However, professional adhesive manufacturers have murmured about this form of operation.
Adhesive industry also has a number of rough workshop manufacturers, in order to reduce costs, conduct illegal operations, arbitrarily reduce production processes, product quality is not guaranteed, shoddy books and magazines use this type of adhesive binding. The low price of such products has affected the quality of binding, disrupted the adhesive market and affected the normal sales of quality products. Among them, some manufacturers only produce adhesives based on a single formula, without any technical personnel, and the product quality is unknown. What's more, it reduces costs by cutting corners or adding major raw material substitutes. For example, EVA hot melt adhesives for books and periodicals require that the EVA content be not less than 50%, but many products on the market do not meet this standard. If these manufacturers do not improve their product levels as quickly as possible, they can only be eliminated in the situation where the quality of binding has been fully improved.
Select product Focus on price
The variety of books and periodicals has a variety of printed materials, and the use of paper and inks is ever-changing. This has led to the diversity of bookbinding, and the need for adhesives to adapt to both types and properties. In the face of different products, the binding department generally selects the corresponding adhesive according to the process requirements and the binding grade requirements. Follow the principle of “comparison of quality under the same quality and comparative quality under the same price”.
From the user's point of view, when selecting the rubber, the user not only pays attention to the cost-effectiveness of the adhesive, but also looks at the “out-of-book rate” of the adhesive, that is, under the premise that the bound thickness and area of a book are bound, the same The weight of glue can glue the number of books, which is also a concrete expression of the pursuit of cost-effectiveness. The high book delivery rate means that the cost of bookbinding is reduced. However, it cannot be denied that some binders do not fully understand the properties and methods of use of adhesives in the selection of rubbers, and they sometimes choose the wrong ones.
The selection of adhesives is also largely related to prices, taking the example of about 3.6 billion adhesive-substrate student textbooks nationwide each year. Due to cost considerations, textbook paper is often made of brittle book paper. In order to make up for this weakness, it should be glued with flexible adhesives. However, the price of hot melt adhesives with good flexibility is higher than that for output. Large student textbooks, many small-size binding manufacturers can not afford, and secondarily, using a low-quality adhesive that does not match the paper, resulting in quality failure should not appear in the binding process.
Is the price issue really insurmountable? According to the analysis of cost-effectiveness, the teacher Wang Huaizhu of the bookbinding expert stated that some high-quality adhesives are not very expensive. Due to the use of imported raw materials, the quality and quality of the products are stable, but the price is higher than that of imported adhesives of the same quality. Low, it is suggested that users with more binding problems can use better domestic adhesives if they want to ensure quality.
Raw material prices rise, quality improvement blocked
In the second half of this year, the price of EVA hot-melt adhesives rose by around 300 to 500 yuan per ton in the world oil prices. This is a powerful shockwave for the raw materials that have been relying on imports for the binding of books and periodicals, making it even more difficult for domestic bookbinding manufacturers to display them. Fist feet. For a large-scale manufacturer with a certain scale, the impact is no small, and for small-scale binding companies, which are originally tight, it is undoubtedly a cold water for the plan that just wants to improve the quality of materials and improve the quality of binding.
At the same time, the publishing house's consideration of reducing costs and the government's request to reduce the cost of printing textbooks has caused the bookbinding companies to resist resistance when they intend to increase the binding costs as raw material prices rise.
Second, application analysis
As for the quality of binding caused by adhesives, all parties in the industry agree that the main issues should be resolved from three aspects: the quality of adhesives, compatibility with other equipment and materials, and the quality of operators.
First of all, the anti-aging properties, high and low temperature resistance, and tensile properties of the adhesive directly affect the quality of the adhesive. The better the anti-aging property, the more collectible the book after the binding, the stronger the preservation. The stronger the resistance to high and low temperatures, the more adaptable to changes in ambient temperature and humidity. The tensile strength and Shore hardness are appropriate to avoid the occurrence of booklet breakage.
Second, consider the compatibility of adhesives with binding equipment, paper, and ink. Good binding equipment, suitable surface compatibility, and other suitable conditions can provide good adhesion.
After the above factors are properly controlled, the operator will also use his or her best efforts. For example, if the operator improperly controls the temperature, it will directly affect the adhesive effect.
Analysis of common faults
Due to the binding quality problems caused by improper use of adhesives, they are almost everywhere in the binding process. Sometimes it will cause unnecessary rework and waste for the next process. From the user's understanding of the main failures are:
(1) Failure caused by improper viscosity. The viscosity is not enough, and the adhesive is too thin to make the adhesive sheet fall off; if the viscosity is too large, the coated layer will be pulled off after the adhesive coated paper will cause the peeling off or the backing paste to be difficult to be separated;
(2) Excessive thickness of the adhesive may result in sticking or tearing of both ends of the back cover of the cover after overflowing;
(3) uneven application of adhesive to make the back cover of the book cover blisters;
(4) Adhesive is not wet enough to apply or dry, so that when the hardback is opened, the back of the book is cracked and the ring lining is pasted. The ring lining and the paper are bonded unevenly or blisters, or the surface of the book case blisters;
(5) The internal tension of the adhesive is greater than the external tensile force, the moisture of the paper is too large, and the resulting hardcover book envelope is upwardly warped after being fitted;
(6) There is no smear in the book
