There are two ways to make one laminated bag: Dry-bond laminating and Wet-bond laminating
Dry-bond laminating is a laminating method where two substrates: the material which is the surface to be printed on, that are not readily permeable to adhesive solvent vapors, are joined together. Adhesive is applied to one of the substrates, which is then dried to remove all volatile substances.
Depending on the type of adhesive used, any excess glue can be dried and removed by using a heated combining roll.
