What is the reason for the heat seal delamination of the composite film?

What is the reason for the heat seal delamination of the composite film?The general reasons for the heat-sealed delamination of the composite film are as follows: 1, the choice of the adhesive is wrong or the heat resistance of the adhesive is too poor. 2, The ratio of curing agent is out of balance. The possible reasons for the imbalance of the curing agent are as follows:; a.human error;b.The ambient temperature is too high;c.The solvent contains moisture, alcohol or activity——OHGene;d.The solvent in the ink has not dried sufficiently. 3, Insufficient curingor the temperature is too low. 4, Insufficient drying. Since the solvent does not volatilize cleanly during printing or compounding, there are many residual solvents. Although these solvents may not have active hydrogen and will not affect the crosslinking reaction of the adhesive, the solvent will swell the adhesive layer, and at high temperature It may vaporize, so although it has little effect on the composite strength at room temperature, it may cause heat seal delamination. 5The influence of printing ink. One is that the unvolatile active agent in the ink, the resin or the additive in the ink consumes a part of the curing agent, which causes the mismatch between the main agent of the adhesive and the curing agent, resulting in the heat-sealing separation layer. The second is that the heat resistance of the ink layer of the ink itself is not good, and the ink layer is damaged during heat sealing, causing the heat seal to separate from the layer. Heat-sealing delamination may occur when heat-labile polyamide inks are used or chlorinated polypropylene inks are used in high-temperature heat-sealing applications.More bag knowledge