Patent ID: 8303749

Claim:
A method for manufacturing composite film, comprising: providing a substrate; uniformly spreading an interface agent on the substrate; uniformly spreading a silicone compound on the interface agent; providing a first mold processed with sandblasting in the inner surface of the first mold by glass sand; disposing the substrate and the silicone compound inside the first mold so that the silicone compound is contacted to the inner surface of the first mold; vulcanizing the substrate and the silicone compound by a predetermined time; forming a composite film with a writing layer and the substrate; characterized in that the silicone compound is uniformly mixed with 37.5% of first silicone, 37.5% of second silicone and 25% of dimethicone, and the glass sand is composed of particles with diameter of 75±25 μm and 125±25 μm by proportion of 1:9; wherein the first silicone is polydimethylsiloxane containing vinyl groups with platinum catalyst and inhibitors, and the second silicone is polydimethylsiloxane containing vinyl groups with fillers of a cross-linker and an inhibitor.