Protective film adhesion means the peel strength when remove the film, we use g/25mm (N/cm N/25mm oz/in) as the unit. There is no international standard to define the adhesion, normally we use SUS board (a special stainless steel board) as the test surface, and remove with 180° peel strength. 

The adhesion can be separated as super low, low, medium, high, there is no same standard define these different adhesion, each company or factory has its own standard. We DUTE protective film makes the standard as below:

Super Low adhesion (5-30g/25mm) mainly applications: plastic boards (PC PVC PP PET PMMA…) ; glass and other high gloss surface.

Low adhesion (30-80g/25mm) mainly applications: Mirrored steel plate; coated metal sheet of gloss finish; smooth aluminum and tile.

Medium adhesion (80-200g/25mm) mainly applications: galvanized aluminum sheet; anodized aluminum; stainless steel; aluminum profile.

High adhesion (more than 200g/25mm) mainly applications: coated stainless steel panel; laminate; carpet; dull painted aluminum profile, coarse sand blasted profile;