Mitsui Minings & Melting Co., Ltd.

Masakazu Mitsuhashi

Naotomi Takahashi

Takashi Kataoka

Hitoshi Kurabe

Muneharu Ohara

Yasuaki Mashiko

Mitsuhito Shibata

An object of the invention is to provide a surface-treated copper foil capable of consistently attaining a percent loss of peel strength in resistance against hydrochloric acid degradation of 10% or less as measured on a copper pattern prepared from the copper foil and having a line width of 0.2 mm, by bringing out the maximum effect of the silane coupling agent employed in brass-plated anti-corrosive copper foil. The Another object is to impart excellent moisture resistance to the surface-treated copper foil. In order to attain these objects, the invention provides a surface-treated copper foil for producing printed wiring boards which has been subjected to nodular treatment and anti-corrosion treatment of a surface of a copper foil, wherein the anti-corrosion treatment includes forming a zinc-copper (brass) plating layer on a surface of the copper foil; forming an electrodeposited chromate layer on the zinc-copper (brass) plating layer; forming a silane-coupling-agent-adsorbed layer on the electrodeposited chromate layer; and drying the copper foil for 2-6 seconds such that the copper foil reaches 105&deg; C.-200&deg; C.

Method of producing a surface-treated copper foil

An object of the invention is to provide a surface-treated copper foil capable of consistently attaining a percent loss in peel strength against hydrochloric acid degradation of 10% or less as measured on a copper pattern prepared from the copper foil and having a line width of 0.2 mm, by bringing out the maximum effect of the silane coupling agent employed in zinc-plated or zinc-alloy-plated anti-corrosive copper foil. Another object is to impart excellent moisture resistance, heat resistance, and long-term storage stability to the surface-treated copper foil. In order to attain these objects, the invention provides a surface-treated copper foil for producing printed wiring boards which has been subjected to nodular treatment and anti-corrosion treatment of a surface of a copper foil, wherein the anti-corrosion treatment includes forming a zinc or zinc alloy plating layer on a surface of the copper foil; forming an electrolytic chromate layer on the zinc or zinc alloy plating layer; forming a chromic-ion-containing silane coupling agent-adsorbed layer on the electrolytic chromate layer; and drying the copper foil for 2-6 seconds such that the copper foil reaches 105&deg; C.-200&deg; C.

The invention provides a surface-treated copper foil for producing printed wiring boards whose surface has,,been subjected to nodular treatment and anti-corrosion treatment, wherein the anti-corrosion treatment includes forming a-zinc-copper-tin ternary alloy anti-corrosive plating layer on a surface of the copper foil; forming an electrolytic chromate layer on the anti-corrosive plating layer; forming a silane-coupling-agent-adsorbed layer on the electrolytic chromate layer; and drying the copper foil for 2-6 seconds such that the copper foil reaches 105&deg; C.-200&deg; C.

Surface-treated copper foil, method of producing the surface-treated copper foil, and copper-clad laminate employing the surface-treated copper foil

The invention provides a surface-treated copper foil for producing printed wiring boards whose surface has been subjected to nodular treatment and anti-corrosion treatments, wherein the anti-corrosion treatment includes forming a zinc-copper-nickel ternary alloy anti-corrosive plating layer on a surface of the copper foil; forming an electrolytic chromate layer on the anti-corrosive plating layer; forming a silane-coupling-agent-absorbed layer on the electrolytic chromate layer; and drying the copper foil for 2-6 seconds such that the copper foil reaches 105&deg; C.-200&deg; C.

A process for producing an electrodeposited copper foil with its surface prepared, comprising the steps of: subjecting an electrodeposited copper foil having a shiny side and a matte side whose average surface roughness (Rz) is in the range of 2.5 to 10 &mgr;m to at least one mechanical polishing so that the average surface roughness (Rz) of the matte side becomes in the range of 1.5 to 3.0 &mgr;m; and subjecting the matte side having undergone the mechanical polishing to a selective chemical polishing so that the average surface roughness (Rz) of the matte side becomes in the range of 0.8 to 2.5 &mgr;m. The invention further provides an electrodeposited copper foil with its surface prepared, produced by the above process, and still further provides PWBs and a multilayer laminate of PWBs, produced with the use of the above electrodeposited copper foil with its surface prepared. The mechanical polishing followed by chemical polishing of the matte side enables obtaining an electrodeposited copper foil with its surface prepared, the matte side of which exhibits excellent properties, and hence enables obtaining PWBs and a multilayer PWBs which have excellent properties.

Electrodeposited copper foil with its surface prepared, process for producing the same and use thereof

A process for producing an electrodeposited copper foil with its surface prepared, comprising the steps of: subjecting an electrodeposited copper foil having a shiny side and a matte side whose average surface roughness (Rz) is in the range of 2.5 to 10 &mgr;m to the first mechanical polishing so that the average surface roughness (Rz) of the matte side becomes 1.5 to 6 &mgr;m; and subjecting the matte side having undergone the first mechanical polishing to at least one further mechanical polishing so that the average surface roughness (Rz) of the matte side becomes 1.0 to 3.0 &mgr;m. The protrudent parts of the matte side are selectively polished by the first mechanical polishing, and the surface having undergone the first mechanical polishing is further subjected to the second and any ensuing mechanical polishings under milder conditions. Thus, a highly planar polished face with excellent surface properties can be obtained. Moreover, depressed parts are not polished, so that the amount of copper lost by the polishings is extremely minute. The use of the electrodeposited copper foil with its surface prepared according to the present invention enables forming a wiring pattern of extremely fine pitch.

A printed circuit inner-layer copper foil having inverted tear drop-shaped fine nodules formed on both surfaces of a copper foil each having surface roughness Rz=1 to 3 .mu.m, the nodules having a length of 0.6 to 1.0 .mu.m and a maximum diameter of 0.2 to 0.8 .mu.m, and a process for producing said inner-layer copper foil.

Growing community of inventors

Ageo, Japan

Masakazu Mitsuhashi