Nitto Boseki Co., Ltd.

Yuuki Numazaki

Hirokazu Inoguchi

Akihiko Watanabe

Naoto Kanno

A transfer sheet for making a printed-wiring board by injection molding which is free from circuit damage during injection molding and has excellent releasability comprises a carrier film, a copper foil circuit, and a releasing layer provided between the carrier film and the copper foil circuit. Preferably, said releasing layer has a T-type peeling strength between the carrier film and the copper foil circuit of 0.025-0.25 kg/25 mm. A method for producing such transfer sheet comprises coating a releasing layer on a carrier film, then contact-bonding a copper foil thereto with heat, pattern-printing an etching resist on the resulting laminate film, and subjecting it to etching to form a copper foil circuit.

Growing community of inventors

Fukushima, Japan

Yuuki Numazaki