§
Luxuse
Patent Intelligence
Sign In
Patent US3158207A successfully refreshed from Google Patents.
← Back to Patent Explorer
EP0541997A2 Expired / Lapsed EP ⏱️ 0.0 years remaining

Surface treatment method of a copper foil for printed circuits

Assignee: Nippon Mining Holdings Inc
•
Filing: 1992-10-20
•
Granted: —
•
Expires: 2012-10-20
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract There is disclosed a treating process whereby the thermal oxidation resistance on the shiny side of a copper foil is enhanced so that the shiny side will not discolor on heating to higher temperatures than usual, without impairing the foil's solder wettability, adhesion to resist, and other properties. A Zn-Ni alloy layer which comprises 50-97 wt% Zn and 3-50 wt% Ni or a Zn-Co alloy layer which comprises 50-97 wt% Zn and 3-50 wt% Co is formed on the shiny side of a copper foil at a deposition quantity of 100-500 µ g/dm² and then the alloy surface is treated for Cr-base corrosion-preventive coating. The Cr-base corrosion-preventive treatment comprises (1) a treatment for forming a coating film of chromium oxide alone, (2) a treatment for forming a mixed coating film of chromium oxide and zinc and/or zinc oxide or (1) + (2). The roughened side of the copper foil may be treated to form thereon a layer of single metal or alloy of two or more metals chosen from among Cu, Cr, Ni, Fe, Co, and Zn. The shiny side does not cause discoloration upon exposure to high-temperature conditions of 240 °C for 30 minutes or 270°C for 10 minutes.

Inventors

  • 👤 Eiji C/O Nikko Gould Foil Co. Ltd. Hino
  • 👤 Keisuke C/O Nikko Gould Foil Co. Ltd. Yamanishi
  • 👤 Kazuhiko C/O Nikko Gould Foil Co. Ltd. Sakaguchi

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-11-02 20:44
CPC Classifications
H; H05; H05K; H05K3/00; H05K3/22; H05K3/24; H05K3/244; C; C23; C23C; C23C22/00; C23C22/05; C23C22/06; C23C22/24; C25; C25D; C25D11/00; C25D11/38; H05K3/38; H05K3/382; H05K3/384; H05K2201/00; H05K2201/03; H05K2201/0332; H05K2201/0335; H05K2201/0355; H05K2203/00; H05K2203/07; H05K2203/0703; H05K2203/0723; H05K3/02; H05K3/06; H05K3/061; H05K3/064; Y; Y10; Y10S; Y10S205/00; Y10S205/92

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 107 words
A process for the surface treatment of a copper foil for printed circuits characterized by the steps of forming either of a Zn-Ni alloy layer which comprises from 50 to 97 percent by weight of Zn and from 3 to 50 percent by weight of Ni or Zn-Co alloy layer which comprises from 50 to 97 percent by weight of Zn and from 3 to 50 percent by weight of Co on the shiny side of a copper foil at a deposition quantity of from 100 to 500 µ g/dm² and then forming a Cr-base corrosion-preventive coating layer on said Zn-Ni alloy layer or Zn-Co alloy layer.
Claim 2
Dependent Claim 41 words
The process of claim 1 in which the roughened side of the copper foil is treated to form thereon a layer of single metal or alloy of two or more metals chosen from among Cu, Cr, Ni, Fe, Co, and Zn.
Claim 3
Dependent Claim 28 words
The process of claim 1 or 2 in which the Cr-base corrosion-preventive coating layer is formed of a chromium oxide film by immersion chromate or electrolytic chromate treatment.
Claim 4
Dependent Claim 32 words
The process of claim 1 or 2 in which the Cr-base corrosion-preventive coating layer is formed of a mixed film of chromium oxide and zinc and/or zinc oxide by electrolytic zinc-chromium treatment.
Claim 5
Dependent Claim 47 words
The process of claim 1 or 2 in which the Cr-base corrosion-preventive coating layer is formed by forming a chromium oxide film by immersion chromate or electrolytic chromate treatment followed by forming a mixed film of chromium oxide and zinc and/or zinc oxide by electrolytic zinc-chromium treatment.

References Cited (Backward Citations)

No citation records indexed.

USPTO Annuity & Maintenance Windows

Maintenance schedule is calculated for granted US utility patents.

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag