Famous Forum: Exploring the Root Cause of Wireless Binding Quality (I)

In recent years, with the acceleration of the publishing pace, there are more and more books printed using flat-packed wireless adhesives. According to incomplete statistics, the books printed in China in the past two years are roughly about 100 billion copies each year, including more than 40 of them. Billion books are processed into booklets using wireless glue binding. Adhesive books used thermal bonding materials EVA hot melt adhesives, use nearly 10,000 tons per year; the use of such adhesive materials for book binding units more than 100,000; wireless adhesive binding equipment only on the linkage production line there One hundred, more than 2,000 units stand alone. The use of glue-binding technology to process a large number of books, the use of large knotted materials, involving a wide range of processing units, is unprecedented in the book binding history. However, it cannot be seen that the quality of book binding has been found to be more serious in recent years. According to the relevant sections, the bound unqualified products accounted for about 65% of the total print quality problems, including wireless adhesives. More than 80% of the non-conforming products caused by order processing accounted for more than 80%. The unqualified products mainly reflected from the surface. After the books and periodicals were processed, there were page-failures, book-backs, book-breaks, bubbles, holes, and spilled glue. Where did the reason come from? Now we analyze from the following points, so that the relevant units can find out the reasons in the actual management work, be solved, and improve the quality of wireless glue processing.

I. Inadequate understanding of the importance of changes in the finishing process

The finishing process is the final finishing process of the printing process, and it is also the final finishing process of book processing. It relates to the preservation value and reading value of the use value of printed products, and affects the above two processes (prepress and printing). The guarantee of processing effect and cycle; no matter how good the printed product is, it will not be properly and firmly connected and beautifully packaged. Can not reflect the value of printed products. Post-press is a very important procedure for the final packaging of printed products.

For a long period of time, people have always had a prejudice against this process. They think that anyone can do the binding, neglecting its importance. At the same time, the quality of the people who have engaged in this work for many years is lower than that before printing and printing. As for Beijing Printing Academy, one of Asia's largest printing institutes, it has not bound such a specialized discipline that accounts for one-third of the total printing industry in the past few years. It is only in recent years that there are some printed and bound books (in the packaging and decoration department). . In large-scale printing information conferences, printing and scientific research associations usually talk about prepress and how to print. For example, only prepress and printing of printed materials will complete the mission, and books can be read without being packed into books. Should this situation continue to continue, can the quality of bookbinding not increase? The quality of book decoration will affect the overall image of our country's book publishing, so we must really draw attention.

Post-press binding is a processing process with complicated equipment, complicated process, multiple material types, and large changes; there are dozens of equipment types, and there are more than 100 models and forms. There are nearly 10 types of linkage production lines and each A line has different models and forms, and there is almost no commonality between stand-alone devices. Post-press has gradually evolved from a manual operation to a modern process of mechanization, linkage, and automation.

Post-press binding is even more complex and involves more than 10 different methods. Some of the assembly methods only have more than 30 processes, and the process changes so much, and the publisher needs to be able to process the staples. Whether you can meet the requirements is rarely valued.

There are hundreds of kinds of bound materials and hundreds of styles. Each kind of material has a lot of knowledge. For example, there are more than 10 cover materials, and the textures of the materials vary. These different materials also involve the use of bonding materials. The difference in the dry knot family is related to the firmness of the kinked object and the kink. The correct use of materials directly affects the firmness of books and their preservation life. At present, the quality problems that arise in wireless glue binding are directly related to the use of EVA hot melt adhesives.

In a word, the finishing process is not only a complicated processing process but also an art processing process. Today's books are not only reading items, but also a kind of gifts, art objects, and valuable preservation products. It not only adds knowledge to humans, but also Give people artistic enjoyment.

Therefore, the effect and value of printed products must be demonstrated by the advantages and disadvantages of the printed binding. For all of us who are engaged in book publishing, production, etc., all staff must clearly understand the complexity of this process, the importance and the overall concept of producing a book, and re-understand and understand this procedure for the publication of high-quality books. .
Second, equipment has changed, the quality of personnel has not changed

The modern printing and binding equipment has entered a period of mechanization, automation, and linkage production. Especially after the middle period of the early 1990s, China has entered the third period of transformation of the binding equipment. Its characteristic is that all are close to international standards. At present, there are about 100 large-scale linkage production lines in China, and the most advanced linkage line has a price of nearly 20 million RMB; computer control, image display, etc., the level of equipment is getting higher and higher, and these equipment management and operation require a certain level of technology. Management and operations personnel are competent. However, it is understood that currently there are very few talents in this field in China, and the existing skilled workers are far from the expected requirements; generally speaking, the equipment comes again, and some units only let the personnel train for a few days and let the machine operate. Most of the equipment comes to the touch of a dry machine that can be turned on the line. As a result, equipment life is shortened, efficiency is not improved, the quality of the finished product does not meet the standard requirements, there is a problem, the equipment resentment is not found. People's reasons; For now, the quality of the team after the printing and binding process, most of them are not graduates of a professional school, and even have not conducted any training, so the basis, and how to adapt to today's modern production? The equipment has become more advanced, and the quality of people has not changed. How can we keep up with the trend of the times?

Third, the process material has changed, the environmental conditions have not changed

As far as the wireless glue binding process is concerned, almost every book processing factory has to deal with it. The majority of the drilling materials used in this process are thermoplastic EVA hot melt adhesives, and the thermoplastic bonding materials are very strict in terms of environment and conditions when they are used. At the "Sino-German binding technology training class" organized by Nanjing Aide Printing Co., Ltd., the German teacher Mr. Stern proposed the importance of environment and conditions when explaining the use of EVA hot melt adhesive, and introduced EVA hot melt adhesive in France. The temperature and humidity of the processing room inside the processing book have certain data control. The temperature is controlled between 19°C and 25°C, and the humidity is controlled at about 50% RH. In China, the temperature required in the wireless glue production workshop is generally up to 17°C. Between 30°C; this requirement is twice as good as abroad. However, most of these requirements cannot be fulfilled except for a small number of units and regions. For example, in southern China, there are many unit-binding workshops that do not use EVA hot-melt adhesives at the highest temperature or air-conditioning temperatures. The temperature is as high as about 38°C, which results in an extension of the curing time after the application of the glue solution, non-hardening setting, and the linkage production line cannot be cut. In the northern winter, when the temperature is low, indoor temperature is the lowest (no constant temperature, air conditioning equipment) to around lO°C, which causes the hot melt adhesive to cure in advance and cannot bond. As for temperature, there is a difference in dry areas. The unqualified standardization of enterprises (general binding workshop without hygrometer apparatus) requires that the expected humidity standard is even more satisfactory; for example, in areas with high rainfall and high humidity in southern China, the maximum humidity in the workshop is about 80% RH. The area is less dry with rain, and the minimum humidity is about 30% RH. Humidity and excessive humidity have a direct impact on the binding effect of paper and books, and can cause various quality problems in the wireless glued book case.

In order to improve the book binding quality. In the binding shop, especially for sites with hot-melt adhesive materials such as EVA, it is necessary to create a good environment and conditions for standardized production.

Fourth, lack of understanding of modern bonding materials

There are two types of adhesive materials used for binding, one is a cold hydrosol; the other is a thermoplastic adhesive. After the adhesive is hot melted, the bonded material is divided into a permeation type, a suction type, and a half. Permeation (also known as semi-attractive), the three types of adhesive materials and adherends are different, but the bonding effect is not the same.

China's binding materials for binding have used cold glue for a long time, cold glue is a water solvent, and its drying method is to set the shape by heating and pressing with the temperature and time.

However, the commonly used thermoplastic adhesives are different, such as EVA hot-melt adhesives, which are solid, moisture-free, fusible, colloidal dry materials that use this material to pass the appropriate melting point (softening) temperature and use temperatures. , Open time, curing time and cooling hardening time, and then the correct clamping and shape, in order to achieve the reliable effect of dry knot. Because EVA hot-melt adhesives are affected in many ways, such as the temperature and humidity of the factory building, the speed of operation, the texture of the paper, the difference between the adhesive and the side adhesive, the temperature of the adhesive, and so on, all are related to the processed products. The pros and cons have a direct relationship.
In addition, there are many publishing houses that require that the thickness of the book's backing glue be as large as possible, and that the more the coating is applied, the more solid it is. This is a misunderstanding. In fact, the fastness of the book book connection is in some sense more than the thickness of the glue. Firmness does not matter. Because the adhesive strength, viscosity, viscosity, etc. can determine the fastness of bookbinding. As long as the adhesive strength, viscosity, and viscosity of the book glue meet the standard requirements, the adhesive layer should be “thin and even”. It is advisable that the book glue is too thick and can only cause the back of the book to be uneven, it is hard to read, the appearance is ugly and the material is wasted.

There are many kinds of cold and hot glues used for binding materials. Among them, EVA hot melt adhesives have different adhesion effects due to different sources of basic materials, different types of auxiliary materials, and differences in the prices of various ingredients and models. Therefore, we must have a thorough understanding of various materials (including cover materials, cardboards, etc.) that are modernly discontinued, strengthen learning, and apply them theoretically to practice, and record their experience at any time. Improve and meet the desired requirements.