| 摘要 |
PROBLEM TO BE SOLVED: To provide a surface protective film that has very few fish eyes, superior blocking property without use of an antiblocking agent, superior flexibility, improved controlling of exfoliation force and improved feed performance. SOLUTION: This surface protective film includes an adhesive layer formed on one side surface of a substrate layer and an exfoliation processing layer formed on the other side surface of the substrate layer. The substrate layer is made of a specific MFR-having propylene-ethylene block copolymer which is produced through sequential polymerization using a metallocene catalyst which makes, at a first step, a propylene homopolymer or a propylene-ethylene random copolymer, and at a second step, a propylene-ethylene random copolymer. The adhesive layer is made of an ethylene-α-olefin copolymer as a main component which is polymerized using the metallocene catalyst, and has a specific density, a TREF value and a molecular weight distribution. The exfoliation processing layer has a central plane average roughness (SRa) on the layer surface of the exfoliation processing layer is within a range of 0.2-1.5μm when measured under a specific condition. COPYRIGHT: (C)2011,JPO&INPIT |
