| 摘要 |
PROBLEM TO BE SOLVED: To provide a release film that can strike a balance between embeddablity to a circuit exposure film and releasability after heating press, in the heating press when producing a circuit board.SOLUTION: A release film 10 has a cushion layer 20 and a release layer 1. The cushion layer has a first resin layer 2 and a second resin layer 3, and in the release film, a vicat softening point X (°C) of the first resin layer and a vicat softening point Y (°C) of the second resin layer are different. The release film can strike a balance between the embedding property to the circuit exposure film, and the mold releasability after the press of pressurizing in the heating press in producing the circuit board by taking the above configuration. |
