A pressure sensitive adhesive and a pressure sensitive adhesive film having thereon a layer of the same.

摘要

A pressure sensitive adhesive film reducible in adhesive force by UV-light comprises a base film permeable to UV-light and a layer of a pressure sensitive adhesive on one side of the base film. The adhesive comprises one elastic polymer selected from apolymer composed of acrylic acid ester copolymersor a saturated copolyester composed of dibasic carboxylic acids and dihydroxy alcohols; 15-200 parts by weight per 100 parts by weight of the elastic polymer of an UV-light polymerizable acrylic acid ester having not less than two acryloyl or methacryloyl groups in the molecule and a molecular weight of not more than 1000; A photopolymerization initiator for inducing the photopolymerization of the UV-light polymerizable acrylic acid ester; The film is suitable as a dicing film in dicing a semiconductor wafer to dices in which the wafer is fixed on the film with a relatively large adhesive force and by UV-light radiation from the other side the adhesive force of the film is reduced that the dice loosely adheres onto the film.