Walk position: glue position shifts when laminating.

Empty line: line marks due to unglued film on plastic film.  

Roller-printing: When laminating, there is a regular mark on the lamination film due to damage or adhesion of dirt on the lamination roller.

White point: The appearance of granular white marks on the surface of the composite film is more common in the composite aluminized film.

Bubbles: Foamy marks due to entrained gases in the composite film during lamination.

Peeling difference: The composite film has poor composite strength.

Crystal spot: The unmelted granular raw material particles are present in the composite film.

PE water mark: It specifically refers to traces of water ripples in the PE film.

Out of ink: Deinking traces of the ink on the printing film that are dissolved by the glue or scraped off by the guide roller due to the film coating process.

Separation: Separation of composite membranes due to poor composite strength.

Whiteness difference: The white-colored PE film is particularly translucent or transparent due to insufficient or unstirred masterbatch.

Uneven thickness: The thickness of the composite film is inconsistent.

Sticky edge: The phenomenon that the adhesion between the edges of the composite film cannot be smoothly unwound when the glue overflows due to lamination.