Mitsui Minings & Melting Co., Ltd.

Kazuhisa Fujiwara

Masanobu Tsushima

Hiroshi Tan

Mitsuo Fujii

Naotomi Takahashi

This invention provides a copper foil for a printed wiring board, which comprises a copper foil, an alloy layer (A) comprising copper, zinc, tin and nickel which is formed on a surface of the copper foil, said surface to be brought into contact with a substrate for a printed wiring board, and a chromate layer which is formed on a surface of the alloy layer (A). The copper foil for a printed wiring board has the following features: even if a printed wiring board is produced using a long-term stored copper foil, the interface between the copper foil and the substrate is only slightly corroded with chemicals; even if the copper foil contacts a varnish containing an organic acid, e.g., a varnish for an acrylic resin, in the formation of a copper-clad laminate, the bond strength is sufficient.

Copper foil for printed wiring board having excellent chemical resistance and heat resistance

To provide a copper foil roll, which is a final product form of copper foil, in which wrinkles generating in the vicinity of a core tube of the copper foil roll are restrained to the utmost, and a better winding balance is provided. A method for winding copper foil on a core tube, in which the copper foil is spliced to a core tube with use of a pressure-sensitive double-sided adhesive coated tape with releasing paper and is wound into a roll form.

Method for winding copper foil on core tube

This invention provides a copper foil for a printed wiring board, which comprises a copper foil, an alloy layer (A) comprising copper, zinc, tin and nickel which is formed on a surface of the copper foil, said surface to be brought into contact with a substrate for a printed wiring board, and a chromate layer which is formed on a surface of the alloy layer (A,. The copper foil for a printed wiring board has the following features: even if a printed wiring board is produced using a long-term stored copper foil, the interface between the copper foil and the substrate is only slightly corroded with chemicals; even if the copper foil contacts a varnish containing an organic acid, e.g., a varnish for an acrylic resin, in the formation of a copper-clad laminate, the bond strength is sufficient. Even if a printed circuit board made by using the copper foil is placed in a high temperature environment, e.g., in an engine room of an automobile, for a long period of time, blistering of the copper circuit from the substrate due to deterioration of the interface between the copper circuit and the substrate does not take place.

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Omiya, Japan

Kazuhisa Fujiwara