Loop tack testing is used to assess the application tack or initial "grab" of pressure sensitive materials. It is particularly relevant to machine applied labels and splicing tapes.
The 'loop' tack of a pressure sensitive material is the force required to separate, at a specified speed, a loop of material (adhesive outermost) which has been brought into contact with a specified area of a standard surface.
Smithers Pira loop tack testing is based on FINAT test method 9. Tests are made against "standard" float glass, stainless steel or other relevant substrate.