Mitsubishi Gas Chemical Company, Inc.

Kenichi Moriyama

Kenji Ishii

Hiroyuki Matsumoto

Kenichi Takahashi

Akira Hosomi

Kazuhiko Ikeda

Takamasa Nakai

Naoki Kogure

Atsushi Hosoda

The surface treatment agent for copper and copper alloys contains hydrogen peroxide, a mineral acid, an azole compound, silver ion and a halide ion. The surface treatment agent for copper and copper alloys is useful in the production of printed wiring boards in electronics industry. The surface treatment agent roughens the surface of copper and copper alloys. Particularly, the surface treatment agent can form a uniform and undulation-free roughened surface on copper-clad substrates having plated mirror surface, this having been difficult in conventional techniques, thereby significantly improving the adhesion to etching resists, solder resists, in addition, to prepregs and a resin for mounting electronic parts.

Surface treatment agent for copper and copper alloy

A process for producing a thin copper foil-clad circuit board substrate which comprises subjecting a copper foil-clad circuit board substrate (a) comprising an electrically insulating support overlaid on one or both sides with a copper foil having an average thickness of 12 .mu.m or more to etching with a copper-etching solution thereby to etch the whole surface of the copper foil at a predetermined etching rate selected from the range of from 0.01 to 0.4 .mu.m/sec, thereby to reduce the thickness of the copper foil on at least one side of the insulating support to 10 to 80% of its original thickness with the thickness variation of the remaining etched copper foil being within .+-.1.0 .mu.m on the basis of a desired thickness, wherein said copper foil-clad circuit board substrate (a) is one in which the surface of the copper foil is substantially free of adherent dust particles having an average particle diameter of 3 .mu.m or more.

Process for producing thin copper foil-clad circuit board substrate

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Kanagawa, Japan

Kenichi Moriyama