| 摘要 |
PROBLEM TO BE SOLVED: To obtain a pressure-sensitive acrylic adhesive tape or sheet which is reduced in the lowering of the peeling force in the region of low rates by forming a multilayer pressure-sensitive adhesive based on an acrylic copolymer so that the affinity of its surface layer for a lowly polar adherend may be higher than that of its inner layer for the adherend. SOLUTION: This pressure-sensitive adhesive tape or sheet is prepared by forming a multilayer pressure-sensitive adhesive layer having at least two layers each of which is based on an acrylic copolymer on either surface of a support, and is characterized in that the affinity of the pressure-sensitive adhesive layer situated on the surface side for a lowly polar adherend is higher than that of an adhesive layer situated inward of the former. The pressure-sensitive layer situated on the surface side has a thickness corresponding to at most 2/5 of the whole pressure-sensitive adhesive layer (desirably 5-500μm) and is made from a composition comprising 100 pts.wt. acrylic copolymer, 5-40 pts.wt. tackifying resin comprising an ester compound of polymerized rosin and a cross-linking agent reactive with the hydroxyl groups of the tackifying resin.
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