Automobile paint film-protective sheet
AssigneesKansai Paint Co., Ltd., Nitto Denko Corporation
InventorsKomaharu Matsui, Mitrso Wakimoto, Takeshi Eda, Tadayoshi Tatsuno, Yutaka Kuwabara, Kenichi Shibata
Life of this patent
Estimating the term…
Abstract
An automobile paint film-protective sheet comprising a substrate having formed on one side thereof a rubber-based pressure-sensitive adhesive having a dynamic modulus of from 2.times.10.sup.5 to 7.times.10.sup.6 dyne/cm.sup.2 at 60.degree. C.
Claims4
A sheet for protecting a melamine-alkyd, melamine-acrylic or urethane automotive paint film wherein said sheet comprises a plastic substrate having a thickness of 10 to 100 .mu.m made of a polypropylene and polyethylene blend and having formed on one side thereof a layer of a rubber-based pressure-sensitive adhesive having a SP value of at least 1 larger or smaller than the automotive paint film, a dynamic modulus of from 4.times.10.sup.5 to 7.times.10.sub.6 dyne/cm.sup.2 at 60.degree. C., an adhesion strength of 100 to 1,000 g/20 mm and a thickness of 5 to 50 .mu.m, said adhesive comprising an isobutylene-based polymer which is not curable, whereby said sheet has a ratio of (i) adhesion strength after exposure at 23.degree. C. for 100 hours in a sunshine weatherometer to (ii) initial adhesion strength of 1.01 to 3.86.
A method for protecting an automobile paint film, which comprises covering a surface of the automobile paint film with a sheet for protecting an automobile paint film comprising a plastic substrate having a thickness of 10 to 100 .mu.m made of a polypropylene and polyethylene blend and having formed on one side thereof a layer of a rubber-based pressure sensitive adhesive having a SP value of at least 1 larger or smaller than that of the automobile paint film, a dynamic modulus of from 4.times.10.sup.5 to 7.times.10.sup.6 dyne/cm.sup.2 at 60.degree. C. an adhesion strength of 100 to 1,000 g/20 mm and a thickness of 5 to 50 .mu.mm, said adhesive composition comprising an isobutylene-based polymer which is not curable, whereby said sheet has a ratio of (i) adhesion strength after exposure at 23.degree. C. for 100 hours in a sunshine weathermeter to (ii) initial adhesion strength of from 1.01 to 3.86.
Dependencies are inferred from the claim text.