Solution: Adjust the heat-sealing temperature to a normal temperature.
The second major reason: in the longitudinal heat-sealing knife section, the running trajectory of the composite film is not straight.
Solution: choose an inner sealing substrate with low temperature heat sealability.
The third major reason is that the film in the composite material has poor heat resistance.
Solution: Reselect the surface substrate film.
The fourth major reason: improper tension matching control of the composite substrate during the compounding process, which results in residual stress after curing and curing, especially if the composite film is thin
Solution: Adjust the tension of each part of the composite processing equipment, and try to make the two kinds of composite substrates shrink equally.
Fifth major reason: the thickness of the paper bag material is not consistent.

Solution: Adjust the tension of the floating roller.