Due to its light weight, small size, fast heat conduction, short sterilization time, and better maintenance of the color and aroma of the contents, retort bags gradually replace some iron cans and glass jars, but due to the many properties of its packaging materials, the packaging bags are restricted. , Sterilization and other processes have a greater impact, so there is a potential risk of bag breakage. 1, substrate problemsThe retort bag is heated together with the product, which determines that the surface material of the retort bag has very good stability after cooking, especially the dimensional stability after cooking and cooling. If the thermal stability of the base material is not good, it is easy to appear After cooking, cooling and shrinking, the layer separation leads to bag breakage.Countermeasures: Retort bags generally use high temperature resistantPET,NY,AL,RCPPand other substrates, attention should be paid to the shelf life of various substrates, especiallyRCPPshelf life, becauseRCPPAs the inner material of high-temperature cooking, it plays a central role in the performance of the cooking bag, ifRCPPThe quality is relatively poor or the shelf life has expired, and it will become brittle and cause rupture to a large extent when it is compressed after cooking and cooling. 2, the impact of bag making processThe temperature, pressure and machine speed of the heat-sealing knife are the three major elements of the retort bag making process, and a reasonable match between the three is required to make a bag with good airtightness.Countermeasures: Due to the high requirements of the use environment, it is generally required that the retort pouch has strong heat-sealing strength. When making retort bags, special attention should be paid to the point sealing of the junction between the bottom and the bag body, because under the cooking conditions, as the material shrinks, the junction will become the focus of moisture and heat attack. The number of heat seals greatly affects the heat seal strength. Reasonably setting the number of horizontal seals and vertical seals during bag making can ensure that each edge seal has good heat seal strength. At the same time, attention should be paid to cooling after heat sealing. When cooling, under a certain pressure, use a lower temperature to shape the position that has just been melted and heat-sealed to eliminate stress concentration.