Some food packaging bags will have problems such as curling, uneven packaging and deformation in the future. What are the reasons for these phenomena? How should we decide?First of all, let me talk about the main reasons for packaging curling and deformation: 1, The heat resistance of the surface substrate film is poor; 21. Improper control of the tension matching of the composite substrate during the composite process, resulting in residual stress after it is matured and shaped, especially when the thickness of the composite film is thinner, such failures are more likely to occur; 3, The thickness of the composite film is inconsistent; 4, Insufficient cooling; 5, The curing time is not enough; 6,In the longitudinal heat-sealing knife part, the running track of the composite film is not straight; 7, The heat sealing temperature is too high or the heat sealing time is too long;Then, since we already know the reason, we should make corresponding adjustments to avoid unnecessary losses. The following are some countermeasures we have summarized: 1, Re-select the surface substrate film, remember not to be greedy for cheap and choose a little knowledge of the substrate; 2, Adjust the tension of each part of the composite processing equipment, try to make the shrinkage ratio of the two composite substrates equal; 3, Adjust the tension of the floating roller during compounding to make the thickness as consistent as possible; 4, full cooling; 5, Fully ripen, but the material should not be overripe or it will easily cause adhesion. This degree must be mastered; 6, Select the inner sealing base material with low temperature heat sealability; 7, Adjust the heat sealing temperature to a suitable temperature.