Mitsui Minings & Melting Co., Ltd.

Toshiko Yokota

Makoto Dobashi

Susumu Takahashi

Hisao Sakai

Yasuji Hara

Tsutomu Asai

Hiroshi Hata

Mitsuo Suzuki

Naotomi Takahashi

Takuya Yamamoto

Hideaki Matsushima

Yoshiaki Kinoshita

Junshi Yoshioka

Hiroaki Kurihara

Tetsuhiro Matsunaga

Tatsuya Sudo

To provide a dielectric-layer-provided copper foil or the like for extremely improving the product yield while making the most use of the increase effect of an electric capacity of a thin dielectric layer using the sputtering vapor deposition method. In the case of dielectric-layer-provided copper foils respectively having a dielectric layer on one side of a copper foil, the dielectric layeris an inorganic-oxide sputter film having a thickness of 1.0 &#x3bc;m or less and formed on the one side of the copper foil in accordance with the sputtering vapor deposition method and the dielectric-layer-provided copper foils for respectively forming a capacitor layer, characterized in that a pit-like defective portion generated on the inorganic-oxide sputter film is sealed by polyimide resin are used.

Copper foil provided with dielectric layer for forming capacitor layer, copper clad laminate for formation of capacitor layer using such copper foil with dielectric layer, and method for manufacturing producing such copper foil with dielectric layer for formation of capacitor layer

The method for electrolytically refining copper makes use of crude copper as an anode and is characterized in that the temperature of the electrolyte in an electrolytic cell is maintained at a level of not less than 55&deg; C.; that the electrolyte is continuously introduced into the electrolytic cell from the top of the cell, continuously discharged from the bottom of the cell along with slime, the slime is removed from the electrolyte discharged from the electrolytic cell and the electrolyte free of any slime is recirculated in the cell; and that the electrolyte is passed through the space between the electrodes at an average electrolyte velocity sufficient for allowing the electrolyte to flow on the whole surface of the cathode downward or in the direction opposite to that of the upward stream of the electrolyte generated on the cathode surface when the electrolysis is initiated while the electrolyte is in the stationary state.

High current density electrolytic decomposition process for copper

A copper foil having improved resistance to abrasion damage during the manufacture of printed circuit boards has a uniform deposit of benzotriazole (BTA) or BTA derivative, optionally a mixture thereof, of at least about 5 mg/m,.

Copper foil for printed circuit boards

A high tensile strength copper foil having a matte side roughness Rz of 2.5 &mgr;m or less and a tensile strength of 40,000 Kgf/mm,after heating one hour at 180&deg; C. is produced by a process in which copper is electrodeposited from a solution containing predetermined small amounts of a polyether glycol and tin and iron ions. The chloride ion content is maintained below 0.1 wt. ppm. The copper foil is characterized by having copper crystals with atomic cells having a predominently (111) orientation.

High tensile strength electrodeposited copper foil

An organic rust-roof treated copper foil characterized in that it has a metallic rust-proof layer formed on the non-adhesive side of the original copper foil and has an organic rust-proof layer formed on said metallic rust-proof layer, the organic rust-proof layer comprising a mixture of at least two kinds of chemicals selected from the group consisting of benzotriazole, its derivatives, aminotriazole and its isomers and derivatives is provided with on said metallic rust-proof layer, or it further has a chromate-treated layer formed between said metallic rust-proof layer and said organic rust-proof layer.

Organic rust-proof treated copper foil

A high tensile strength copper foil having a matte side roughness Rz of 2.5 .mu.m or less and a tensile strength of 40,000 Kgf/mm.sup.2 after heating one hour at 180.degree. C. is produced by a process in which copper is electrodeposited from a solution containing predetermined small amounts of a polyether glycol and tin and iron ions. The chloride ion content is maintained below 0.1 wt. ppm. The copper foil is characterized by having copper crystals with atomic cells having a predominantly (111) orientation.

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Saitama, Japan

Toshiko Yokota