| 摘要 |
PROBLEM TO BE SOLVED: To prepare a surface protection film having excellent initial stickiness, sparingly causing the increase of stickiness even when placed under a high temperature condition and enabling separation of the film itself from an object to be protected to be easily performed by forming a pressure sensitive adhesive layer with a specific tetra-block copolymer. SOLUTION: This surface protection film is obtained by the coextruding of a thermoplastic polyolefin-based resin as (i) a substrate layer together with a pressure sensitive adhesive to form (ii) a pressure sensitive adhesive layer on the layer (i). The layer (ii) is composed of a tetra-block copolymer expressed by the formula A-B-A1-B1 (wherein A and A1 are each a styrene polymer block and; B and B1 are each a butadiene polymer block or a polymer block obtained by the hydrogenation of an isoprene polymer block). The component (ii) preferably comprises 100 pts.wt. tetra-block copolymer expressed by the above formula and 5-100 pts.wt.α-methylstyrene resin.
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