High-temperature retort bags are plastic flexible packaging used to package retort food. In the division, according to the temperature, the≤100℃ is called water-resistant bag, in121-125℃ is called retort-resistant bag, in≥135℃ is called high temperature resistant cooking bag. During the cooking process, many people will encounter the rupture of the packaging bag. What are the reasons for this?

1. The oil film or glue used in the high-temperature cooking bag does not meet the boiling requirementsRegardless of the type of ink or glue used in high-temperature retort bags, it is usually made of polyurethane resin. The high moisture and heat resistance of polyurethane resin contributes to the adhesion and high-temperature resistance of the retort bag. Therefore, if the retort pouch breaks at this step, it may be that the ink or glue used is attacked by moisture during the heating process in water, and a chemical reaction such as hydrolysis occurs, thereby reducing the viscosity of the retort pouch. If this problem occurs, you can Ask the supplier of ink or glue, you can ask him to change the chemical structure corresponding to the polyurethane resin. Of course, larger food packaging factories can use curing agents to make up for the increase in the bonding strength of high-temperature cooking bags during cooking.Second, the food packaging bag factory has problems in the use of ink or glueIn the high-temperature cooking process, the amount of curing agent used does not meet the requirements and the curing time is not enough. The cooking time for the cooking bag is generally48Of course, corresponding adjustments should be made according to the actual situation. In the process of mixing the curing agent, the ratio will also affect the amount. Too much or too little will cause the ink to delaminate and break the skin. Therefore, these need professional personnel to make the ratio, so as to improve the adhesion of the boiled bag .

3. There is a problem with the film of the high-temperature cooking bagThe retort bag film will appear to have a degree of treatment that does not meet the requirements, or is not treated at all. However, the staff often did not discover this problem, so that the adhesion fastness was not high after printing, compounding, and curing, and this problem was discovered only after delamination (broken skin) after cooking. The damage caused in the production process of packaging bags is huge. Therefore, we need to improve the technology and proficiency of our employees.

4. Insufficient coordination among ink, glue and filmFrom the adhesion theory, we can know that the adhesion strength*High, interfacial tension required*Small. Therefore, the surface of the ink and glue after curing into a film and the condition of the film surface will be different due to different packaging color printing factories, because the groups on the various surfaces cannot be well attracted to form intermolecular forces or chemical reactions to form Chemical bonds, even if they have a certain effect at low temperature to form adhesion, but at high temperature, the weak connection of surface groups may be damaged and delamination occurs.After the delamination of the high-temperature retort bag occurs, the packaging factory must immediately carefully identify which production process caused the delamination, find out which materials are related to it, and check whether the production process is operated according to the requirements. At the same time, it can be replaced Materials for comparative testing to find out the real cause of delamination.