Advantages of solvent-free flexible packaging polyurethane laminating adhesive production and application

Solvent-free polyurethane laminating adhesives are the core material for the green upgrade of flexible packaging. They eliminate the use of large amounts of organic solvents in traditional solvent-based adhesives, meeting the dual development requirements of environmental protection and safe production in the packaging industry. They have now been widely applied in the production of snack, frozen food, and seasoning composite films. 

 

The traditional solvent-based glue production process releases VOCs, requires a large amount of waste gas treatment equipment, increases the operating costs of the factory, and the residual solvents pose safety risks to food packaging. The solvent-free system does not contain organic solvents such as ethyl acetate, and the lamination processing has no volatile waste gas. The production environment in the workshop is clean, the investment in waste gas treatment is significantly reduced, the residual solvent content in the finished products is far below the national standard limit, and it is suitable for high-end food and infant supplementary food packaging. 

From the perspective of processing performance, the solvent-free two-component Polyurethane Adhesive does not require drying in an oven. The lamination production line eliminates long sections of drying equipment, significantly reducing equipment energy consumption. At the same time, the production speed can be steadily increased, effectively enhancing the factory's production capacity. After curing, the adhesive has excellent internal cohesion strength, firmly adhering to VMPET and aluminum foil barrier substrates. The laminated product is resistant to boiling water and oil penetration. 

 

This laminating adhesive also has usage thresholds. The ratio of the two components and the coating temperature need to be precisely controlled. An imbalance in the ratio may lead to incomplete curing and insufficient peel strength. Currently, the industry is continuously improving the formula and simplifying the operation process. Solvent-free polyurethane laminating adhesives are gradually becoming the mainstream choice for flexible packaging laminating.