First, the progress of dry composite

In recent years, the progress of dry composite mainly in the development and use of adhesives, the most notable are the following categories.



1. Development and application of alcohol-soluble adhesives



In recent years, some domestic adhesive production enterprises with strong technical force, has launched a dry composite with alcohol-soluble adhesives and put into practical application, has been the industry's many composite flexible packaging enterprises. Alcohol-soluble adhesive to ethanol as the main solvent, instead of ester-soluble adhesive solvent ethyl acetate, the production of dry laminating adhesive, because of alcohol-soluble adhesive than ester-soluble adhesive has a better adaptability to environmental protection, adhesive effect is better, can significantly reduce the amount of adhesive dry base coating, there is also a high initial adhesion, composite process is not easy to be affected by the impact of air humidity and other advantages in overcoming the inherent shortcomings of the ester-soluble adhesive In overcoming the inherent shortcomings of ester-soluble adhesives show good results. www.susumino.com薄膜复合机






(1) has a relatively good environmental protection adaptability

Ethanol and ethyl acetate are organic solvents, should not exist in the atmosphere in large quantities, but the maximum concentration allowed there is a big difference, ethanol in the air for the maximum concentration of ethyl acetate in the air for the maximum concentration of more than 6 times the maximum allowable, the results of toxicity tests in mice also clearly show that the toxicity of ethanol is much smaller than the toxicity of ethyl acetate. Comparison of the toxicity of ethanol and ethyl acetate, alcohol-soluble adhesive environmental adaptability is much better than the ester-soluble adhesive.



(2) Contribute to the reduction of production cost reduction



Alcohol-soluble adhesive dry base coating volume is lower, generally coated between 1.5~3.0g/㎡, ester-soluble adhesive dry base coating volume is generally above 3.0g/㎡. Therefore, the use of alcohol-soluble adhesive, gluing costs are expected to reduce about 15%; at the same time alcohol-soluble adhesive main agent and curing agent do not contain isocyanate groups, the adhesive will not be affected by the moisture in the air deterioration, and its initial viscosity than the ester-soluble adhesive is large, so the use of alcohol-soluble adhesive, compared with the use of ester-soluble adhesive, the composite is not easy to produce waste products, the genuine rate is high, which is also a favourable factor to reduce production costs. Reduce the production cost of a favourable factor.



(3) Improve the hygiene performance of composite film



Barrier composite film is used in a large number of food, pharmaceutical products packaging, so health and safety is one of the most concerned about the performance. Due to the ester-soluble adhesive solvent ethyl acetate, the human body has a greater toxicity, in order to ensure safety, the residual amount of composite film is required to be less than 10mg / ㎡, if the production process of the production line operation is out of control, the composite film in the residual solvent exceeds the standard, is prone to cause serious health and safety accidents; when the use of alcohol-soluble adhesive, the situation is completely different, it is known that the wine is a traditional Chinese food cooking condiments, long-term application so far, there has not been any accident due to the use of wine. Long-term application so far has not occurred due to alcohol condiments caused by any poisoning accidents, dry composite even if the composite film has a trace of ethanol residue, but also will not endanger the health and safety of the packaged goods. Due to the alcohol-soluble adhesive has all the above advantages, its development and application, is considered to be a major progress of dry composite, but it still has great defects, and did not completely solve the classic dry composite problem: the environmental pollution is just a significant reduction, but not completely eliminated; a large number of solvent ethanol emissions, waste of material resources has not yet been eliminated fundamentally; the problem of large energy consumption still exists; alcohol-soluble adhesive Another problem of alcohol-soluble adhesives is that it can not be used for the production of barrier packaging films. www.susumino.com薄膜复合机



2. The development and application of water-based adhesives

Water-based adhesive and ester-soluble adhesive, alcohol-soluble adhesive is different, it does not use organic solvents, but the use of nature's rich natural resources - water as a solvent or dispersant adhesive. In dry lamination, the use of water-based adhesives, drying process volatility, emissions are not organic solvents (esters or alcohols) but water vapour, so not only to avoid a large number of precious organic solvents waste, but also fundamentally avoid the toxic and harmful organic substances on the operator and the environment hazards, eliminating residual solvents on the product of the adverse impact of hygiene performance. In addition, because water will not burn, will not explode, water-based adhesives for the production process is also more favourable to safety. In recent years, food and its packaging health and safety performance, more and more people's attention, energy saving and environmental protection awareness continues to improve, thus greatly accelerating the dry composite water-based adhesives to replace solvent-based adhesive process. It is said that in the United States, water-based adhesives have accounted for more than 30% of the market share of flexible packaging adhesives, water-based adhesives are generally recognised as