| 摘要 |
PROBLEM TO BE SOLVED: To provide a release film having excellent releasability, migration, oligomer sealability, blocking property, and surface smoothness, as a supporting body for producing a film-like interlayer insulation material.SOLUTION: A release film includes a coating layer and a release layer including a curable silicone resin, sequentially provided on one surface of a laminated polyester film composed of at least two layers and comprising polyester layers not including an antimony element at both outermost layers. An amount of oligomer extracted by dimethylformamide from a surface of the release layer after heat treatment at 180°C for 30 minutes is 0.6 mg/mor lower. A silicone migration amount of one surface of the release layer (100°C) is 4.0 kcps or lower. Arithmetic average roughness of one surface of the release layer (Ra(A)) is 1-5 nm. Arithmetic average roughness of the other surface without the release layer (Ra(B)) is 10-50 nm. A ratio (Rz(A)/Ra(A)) of ten-point average roughness of a surface of the release layer (Rz(A)) and the arithmetic average roughness (Ra(A)) is 3-10. |
