| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a surface protective film which neither raises adhesive force nor pollutes an adherend and never causes a hit mark defect such as a recess, a deformation and the like of the adherend for an optical film such as a polarizing plate, a phase difference plate and the like each requiring a high grade quality such that there generates no recess, deformation and the like of the adherend due to a defect such as particularly a fine fish eye and the like, a wind crease, fine unevenness of the back layer surface and the like in a lamination constitution composed of an adhesive layer, an intermediate layer and the back layer. <P>SOLUTION: The protective film is a surface protective film composed of a three-layer lamination form of the adhesive layer, the back layer and the intermediate layer. The adhesive layer is composed of at least one kind selected from a group consisting of an ethylene-α-olefin copolymer and an ethylene-methyl methacrylate copolymer. The intermediate layer contains at least one kind selected from a group consisting of a polyethylene-based resin and an ethylene-methyl methacrylate copolymer each having a density of 0.870 to 0.935 g/cm<SP POS="POST">3</SP>. The back layer is composed of a polypropylene-based resin and a polyethylene-based resin. Regarding the surface roughness of the back layer, the center surface average roughness (SRa) in accordance with JIS B 0601-1982 is 0.2 to 0.6 μm, the ten-score average roughness (SRz) in accordance with the same is 2.0 to 5.0 μm, and the unevenness average space (RSm) in accordance with ISO 4287-1997 is not more than 0.08 μm. <P>COPYRIGHT: (C)2012,JPO&INPIT |
