Synthetic adhesives have many features such as wide application, easy use, high economic benefits, and rapid development. With the development of economy and advancement of science and technology, it will be more and more important to people's attention and become an industry with great development prospects.
Adhesives have really begun to produce with scale in our country, starting from 1958. In the 1980s, the development of adhesives had a climax. At present, there are more than 1,500 adhesives production enterprises in China, with more than 3,000 varieties, and it has become one of the fastest-growing key industries in China's chemical industry. The synthetic adhesive industry in the developed countries of the world has entered a highly developed stage. The average growth rate in the 1990s was about 3%, and the average growth in China was 19.5%. In 1998, global sales of synthetic adhesives were approximately 25 billion U.S. dollars, of which the United States accounted for about 35% of global sales, western Europe accounted for 25%, Japan accounted for 15%, and China accounted for only 7%. The global synthetic adhesive consumption structure accounts for 35% of the packaging industry, the construction industry accounts for 25%, the wood processing industry accounts for 20%, the automobile transportation industry accounts for 10%, and the Others account for 10%.
From the adhesive application structure, it can be seen that the packaging industry is the largest industry for adhesives. It is widely distributed in various fields such as paper products, printing and decorating, plastics, and other packaging industries. At the same time, with the development of the adhesive industry, packaging products have also been improved. Quality and grade promote the development of the packaging industry.
1. The adhesive carton and carton production industry for cartons and cartons is the industry with the largest amount of adhesives in China. At present, there are about 15,000 cartons and carton manufacturers in China. When producing cartons and carton boxes at the beginning, battoin was used. Adhesives. Due to the fact that scouring alkali adhesives are easy to return to moisture and efflorescence, the adhesive strength is low, and cartons and cartons bonded with them are easily deformed and discolored. Therefore, as early as 1985, the state has banned the use of starch sticks. Mixtures or other binders with the same effect.
At present, in addition to the use of scouring alkali adhesives in low-grade boxes, starch adhesives or other equivalent adhesives have been used in the automatic production lines for high-grade cartons and cartons. Starch binder production technology has also been continuously updated, from the heating production in the 1980s to the current cold water production; from the earliest development of colloids (liquids) to various types of solid rubber powders, adhesive production technology has greatly improved Convenient for the production of cartons and cartons, the drying speed of the carton cartons has been developed from the original more than 40 hours to the current one more hours to enter the next process. Initially, starch binders were only used in the production of high-grade cartons. Today, they can be used to produce various grades of cartons. Progress in non-denatured starches has played a key role in the development of the cartons and cartons industry in China.
Second, packaging and printing adhesives With the improvement of people's living standards, there is a higher demand for packaging, especially sales packaging, such as we see smoke, wine, medicine, cosmetics and other exquisite packaging. In order to achieve the purpose of beautifying the packaging, the film should be coated on the printed matter. The film can increase the luster and make it more eye-catching without affecting the original tone of the print. It can also prevent moisture, stains, and abrasion. , thus effectively protecting the inner layer. Film adhesives and coatings are also being developed. They are usually solvent-based or emulsion adhesives such as E-VA, polyurethanes, polyacrylates, rubbers, and polyesters. Laminating adhesives are organic solvent-based adhesives. The solvents used are usually toluene, ethyl acetate, and solvent oils, which account for more than 60% of the total amount of adhesives. Therefore, they not only pollute the environment and endanger the health of workers, but also may Fire caused, with the emphasis on environmental protection at home and abroad, prompted printing companies to choose adhesives that can meet quality requirements and meet environmental requirements.
Water-based paper-plastic composite adhesive uses water as the medium, has strong adhesive force, non-toxic, odorless, non-burning, no three-pollution hazards, safe to use, high transparency and high gloss, plus it is safe to use, to the workers No damage, no pollution to the environment, so welcomed by the printing industry, has been widely used in packaging and printing, books and other areas of printing.
Third, pressure-sensitive adhesive and pressure-sensitive adhesive tape Pressure-sensitive adhesive and pressure-sensitive adhesive tape production and application have made great progress in recent years. In 1996, China's market sales of tapes reached 2.26 billion m2, most of which were packaging tapes (2 billion m2). After entering the 1990s, the domestic production technology of pressure sensitive adhesives gradually developed toward the direction of comprehensiveness. The United States, Japan, and other countries have successively established sole proprietorships or joint ventures in China, and have promoted the improvement of the technical level of China's pressure sensitive adhesive products in certain procedures. For example, in the production of double-sided adhesive tapes, it has been possible to use acrylate soft monomer solution copolymer resins and various cross-linking agents to obtain pressure-sensitive adhesives and products with excellent properties in the form of diplomatic links; Pressure-sensitive adhesive products and radiation-curable pressure-sensitive adhesives also draw on foreign advanced technologies and have now been produced by a number of companies.
In the development and production of high-performance special pressure-sensitive adhesives in China, such as automotive high-strength protective tapes, strong adhesion adhesive tapes for lifting, and high-temperature and high-insulation special tapes, etc., further research is needed and needs improvement. In addition to the above types of adhesives, China's other packaging adhesives such as labels, paper plastic sealing glue, cigarette glue, paper tube glue also with the development of various production technology requirements, continue to update.
Although China's packaging adhesives have achieved remarkable development in the past decade, there are still some gaps between them and the world's advanced level in many aspects. The major ones are: varieties and quality can not fully meet the requirements, many varieties still need to be imported; application technology research can not keep up The requirements for the development of new varieties, backward production equipment, and low level of repeated varieties are still many. At present, there are no systematic national, industrial materials and testing methods.