Water-based composite adhesive reduces residual solvent

The composite film flexible packaging, which can function as a barrier and can be printed and heat-sealed at the same time, has been widely used in food, medicine, cosmetics and other fields. It has greatly replaced the packaging of glass, tinplate, paper and cardboard, and its superiority is universal. know. However, at present, more than 90% of solvent-based polyurethane adhesives are used in the dry composite manufacturing process of composite films. The largest area of ​​solvent-based polyurethane adhesives is compounding of Food Packaging and composite paper. The volatilization of a large amount of solvents not only causes environmental pollution, but also residual solvents in food bags can affect the quality and safety of foods.

Zhejiang Huangyan Huaguang Resin Co., Ltd., a subsidiary company of Zhejiang New Oriental Ink Group, to meet the strong demands of customers, upgraded the products comprehensively, greatly reduced the solvent residues in the composite flexible packaging, and developed W-8830 through cooperation with relevant experts. 8820 water-based polyurethane coating adhesive. The adhesive uses water as the solvent, which fully meets the food hygiene requirements of today's flexible packaging. At present, developed countries in Europe and the United States have already established relevant food hygiene regulations, such as the US Food and Drug Administration FDA, the EU's EU90/128, and Germany's BgVV, which clearly specify the type of adhesive used for food and pharmaceutical packaging, provided that Chemicals that are not mentioned in the regulations are strictly prohibited. Therefore, the current use of solvent-based adhesive composite packaging materials in Europe and the United States has been reduced from 80% 10 years ago to the current 30%. At present, most of the thousands of compound packaging production lines in China still use solvent-based adhesives. China's exports to Japan, the European Union's tea, mushrooms, meat and other foods have all been returned due to health and safety issues. Therefore, food hygiene and packaging not only threaten people's health, but also affect China's export economy. With the continuous improvement of people's awareness of environmental protection, food packaging materials will become more green and environmentally friendly.

In order to completely eradicate the residual solvent hazards of composite flexible packaging, water-based adhesives have become a key issue in domestic adhesive research and development. According to statistics, China's food composite flexible packaging bags require about 50,000 tons of adhesive per year, of which solvent-based polyurethane adhesives account for more than 90%, and solvent-free and water-based composite adhesives less than 10%. Experts believe that the flexible packaging made of solvent-free composite adhesives cannot meet the requirements for boiling and high-temperature cooking, and has a narrow range of applications and requires specialized composite equipment, which limits its use.

The water-based composite adhesive can be directly applied to a dry composite device and can achieve the same effect as a solvent-based adhesive. Water-based polyurethane adhesive is a kind of polyurethane adhesive that uses water instead of organic solvents. It is an environment-friendly adhesive. No harmful solvents are volatilized and no odor is produced in the production process of composite packaging. The residue is fundamentally eliminated. Solvents. The biggest advantage of this kind of water-based adhesive is that it can be directly used without the need for equipment modification and additional investment in the existing compound film production line using solvent-based adhesives in food packaging plants, and the overall cost of water-based adhesives is not high. Existing domestic solvent-based adhesives have been widely promoted in domestic enterprises. Its main product features are as follows: First, water is solvent, non-flammable, does not pollute the environment, and has good hygienic properties; it is not sensitive to the wet working environment and improves the stability and adaptability of the product; the glue liquid has good fluidity and moderate drying speed. Good compatibility with solvent-based inks or water-based inks; good transparency to composite film; good adaptability to the machine; no need to remold the composite machine; glue can be used directly without dilution; odor.

The water-borne polyurethane film adhesive developed by Zhejiang Huangyan Huaguang Resin Co., Ltd. will effectively reduce the solvent residues in the composite flexible packaging, which will play a significant role in promoting the use of the flexible packaging industry in China.

Source: China Chemical Network