From the point of view of raw materials and process flow, the reasons for the adhesion of the composite film come from the following eight aspects: the wrong proportion of adhesive, improper storage of adhesive, water content of diluent, residual alcohol, residual solvent, excessive coating amount of adhesive, insufficient aging and additives.
1. The adhesive ratio is wrong, and the weight of the adhesive is wrong, resulting in insufficient curing. In this regard, all materials should be weighed and recorded to facilitate inspection; secondly, the prepared adhesive should be fully stirred in the right way to avoid local uneven mixing.
2. Improper storage of adhesive, incomplete sealing of curing agent, reaction with moisture in the air, consumption of another part, resulting in insufficient content of curing agent after mixing. Therefore, check the sealing condition of the adhesive before use.
3. The diluent contains water. The purity of the diluent is not high and contains excessive moisture. The proportion of adhesives is out of proportion due to alcohols. The storage of diluent should be sealed to prevent water vapor from entering. The water content of diluent should be tested regularly.
4. Alcohol residue the alcohol component of alcohol soluble ink or ink thinner is not dried, so that it reacts with curing agent and causes sticky. Alcohol soluble ink should use alcohol soluble adhesive, printing solvent should not use alcohol ratio.
5. There are too many residual solvents in the solvent residual composite, and the solvent is wrapped in the adhesive, which hinders the curing. Often check whether the air inlet and exhaust of the drying system is normal, and control the compound speed when the glue amount is large.
6. Too much adhesive coating, too much adhesive coating, too large film roll diameter, resulting in slow internal hardening of adhesive. Adhesive coating to be appropriate, mature to be sufficient.
The curing temperature is too low. Appropriate curing temperature and time should be selected. If necessary, fast curing adhesive should be selected.
8. The influence of additives in the composite membrane substrate, such as the additives in PVDC can delay and prevent the crosslinking and curing of the adhesive, the softener in PVC can react with - NCO group of the curing agent, and the plasticizer of soft PVC can penetrate into the adhesive, which will reduce the adhesive force and thermal stability. Therefore, the amount of curing agent should be increased appropriately.
Dongguan Beite packaging materials Co., Ltd. - located in Dongguan City, the world's manufacturing city, is a subsidiary of Beite packaging (China) Co., Ltd., with a plant area of 6000 square meters. It is a flexible packaging enterprise integrating R & D, production and sales. It has a complete set of domestic advanced production equipment, a scientific and humanized management system and a group of experienced technical personnel For backing, to provide customers with quality products and first-class service.
The company produces composite bags, roll film, fruit bags, aluminum foil bags, suction mouth bags, self-supporting bags, zipper bags, anti-static bags, special-shaped bags, etc., which are suitable for the internal and external packaging of food, daily chemicals, electronics, toys, medicine, cosmetics, industrial products and other industries.
We uphold the integrity of cooperation, good quality, good service business philosophy, won the industry's approval, products sold to all over the world; welcome friends from all walks of life to inquire, visit our factory to investigate guidance and business negotiations.