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. Synthetic adhesives have many characteristics such as wide application, easy use, high economic benefit, and rapid development. With the development of economy and advancement of science and technology, it will be more and more valued by people and become an industry with great development prospects. In China, it began to have a large-scale production. It began in 1958. In the 1980s, the development of adhesives culminated. However, the synthetic adhesive industry in developed countries in the world has entered a highly advanced 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 accounted for 35% of the packaging industry, the construction industry accounted for 25%, the wood processing industry accounted for 20%, the automobile transportation industry accounted for 10%, and the others accounted 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, it has also improved the packaging products. Quality and grade promote the development of the packaging industry.
A, carton, carton
The cartons and cartons production industry is the industry with the largest amount of adhesives in China. At present, there are more than 15,000 cartons and carton manufacturers in China. When the cartons and cartons were first produced, foaming alkali adhesives were used. Due to the fact that scouring alkali adhesives are easy to dampen and efflorescence, the adhesive strength is low, and the cartons and cartons bonded with them are easily deformed and discolored. Therefore, as early as 1985, the country had banned the use of starch adhesives and required the use of starch bonding. Agent or other binder with equivalent 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-end cartons and cartons. Starch binder production technology has also been continuously updated and developed, from the heating production in the 1980s to the current cold water production; from the earliest colloid (liquid) development to various types of solid powder, adhesive production technology The increase greatly facilitates the production of cartons and cartons, and the drying speed of the carton cartons has been developed from the original more than 40 hours to more than 1 hour now to enter the next process. Initially, starch binders were used only for the production of high-grade cartons. Today, they can be used to produce cartons of various grades. Advances in non-denatured starch glue technology have played a key role in the development of China's cartons and cartons industry.
Second, packaging and printing
In order to achieve the purpose of beautifying the packaging, a film shall be applied to the printed matter on the packaging. The film may increase the luster and make it more eye-catching without changing the original tone of the printed material, and it may be moisture-proof, anti-fouling, and abrasion-resistant. This effectively protects the inner layer. The adhesive and film industries for film coating are also evolving, and solvent-based or emulsion-based adhesives such as E-VA, polyurethane, polyacrylate, rubber, and polyester are commonly used. The adhesive is an organic solvent type adhesive, and the solvent used is usually toluene, ethyl acetate, solvent oil, etc., accounting for more than 60% of the total amount of the adhesive. Therefore, it not only pollutes the environment, endangers the health of the workers, but also may cause fire during the operation process. With the emphasis on environmental protection at home and abroad, printing companies are encouraged to choose adhesives that meet both quality requirements and 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 use, high transparency and high gloss, plus it is safe to use on 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
The production and application of pressure-sensitive adhesives and pressure-sensitive adhesive tapes have also seen considerable development in recent years. In 1996, China's market sales of tapes reached 2.26 billion m2, the vast majority of which were packaging tapes (2 billion m2). After entering the 1990s, the production technology of domestic pressure-sensitive adhesives gradually developed toward the direction of comprehensiveness. The United States, Japan, and other countries have successively established wholly-owned or joint ventures in China, which has, to some extent, promoted the technical level of China's pressure sensitive adhesive products. improve. 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; for example, in the development of hot melt. 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 main 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.
Source of information: China Jiaotie Network