As a converter of flexible materials, you often hear us talking about pressure-sensitive adhesives, foams, foils, and films. These are the core materials for parts we create, but we supply many of our finished goods on sheets or a roll. When a component is on a sheet or roll, the parts that we die-cut laminate to a release liner, but you can’t use any old liner, though. Often, the liner is one of the more critical selections. It has to have the right qualities and features to match your application. The good news is you have options.
Release Liner – A release liner is a precise delivery and dispensing system for pressure-sensitive adhesive components. There are two categoies: paper or film. Paper liners generally have four types: Densified Kraft (DK), Extended Densified Kraft (XL), Polycoated Kraft (PCK), and Extensible Polycoated Kraft (EK). Film liners generally have two types: Polyester (PET) and High-Density Polyethylene (HDPE).
Manufacturers coat a release agent on liners to laminate and protect the adhesive it is applying to from exposure before use. The release level is the degree of separation of the adhesive from the paper or film while the liner is the paper or film carrier for the adhesive.