To obtain a film excellent in a releasing property suffering from no protrusion of a resin constituting an insulating adhesive layer by forming a barrier layer such as a resin film or a metal film between a support layer made of a polyester and a pressure sensitive adhesive, thereby preventing the migration of an oligomer to the pressure sensitive adhesive layer.
A pressure sensitive adhesive film comprises a support having a thickness of 12-125 μm made of a polyester film such as a polyethylene terephthalate or the like, a pressure sensitive adhesive coated on one side of the film and a barrier layer formed between the support and the pressure sensitive adhesive and composed of a resin film, a metal foil or a metalized film or the like. The pressure sensitive adhesive is obtained by compounding a copolymer having a wt. average mol.wt. of at least 500,000 and a glass transition temperature of -30 to -50°C and comprising at least 50 wt.% of an acrylic monomer or methacrylic acid monomer and 1-50 wt.% of a functional group- containing monomer such as hydroxyalkyl methacrylate or the like with an isocyanate crosslinking agent such as triphenylmethane triisocyanate or the like.
SAKUMA KAZUNORI
INOUE ATSUSHI
