US5114543A
Expired / Lapsed
US
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Method of making thin copper foil for printed wiring board
Assignee: Fukuda Kinoku Hakafun Kogyo KK
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Filing: 1991-03-18
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Granted: 1992-05-19
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Expires: 2011-03-18
Abstract
Abstract A thin copper foil for a printed wiring board comprising a copper foil supporter having a rough surface on at least a side thereof, a parting layer laid on the side of the rough surface, a thin copper foil layer laid on the parting layer, and a copper-nickel compound metal layer interposed between the parting layer and the thin copper foil layer, and a method of manufacturing thereof.
Inventors
- 👤 Toshiyuki Kajiwara
- 👤 Yoshinori Tanii
- 👤 Kazuhiko Hashimoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 11:53
CPC Classifications
H; H05; H05K; H05K3/00; H05K3/02; H05K3/022; H05K3/025; H05K2201/00; H05K2201/03; H05K2201/0332; H05K2201/0335; H05K2201/0338; H05K2203/00; H05K2203/01; H05K2203/0147; H05K2203/0152; H05K2203/03; H05K2203/0307; H05K2203/0315; H05K2203/0361; H05K2203/07; H05K2203/0703; H05K2203/0723; H05K2203/0726; H05K3/38; H05K3/382
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
134 words
A method of manufacturing a thin copper foil for a printed wiring board comprising the steps of: (a) preparing a copper foil supporter having a rough surface on at least a side thereof, (b) forming a parting layer on the rough surface of the copper foil supporter by immersing the rough surface in a chromate bath including hexavalent chromium ions and keeping a value of pH between 2.0 and 6.5, (c) forming a copper-nickel compound metal layer by immersing the parting layer in a compound metal plating bath including cupric ions, nickel ions and citric acid and keeping a value of pH more than 5.0 and by plating same by means of cathodic electrolysis, and (d) immersing the copper-nickel compound metal layer in an electric plating bath to deposit a thin copper foil layer.
Claim 2
Independent Claim
134 words
A method of manufacturing a thin copper foil for a printed wiring board comprising the steps of: (a) preparing a copper foil supporter having a rough surface on at least a side thereof, (b) forming a parting layer on the rough surface of the copper foil supporter by immersing the rough surface in a chromate bath including hexavalent chromium ions and keeping a value of pH between 2.0 and 6.5, (c) forming a copper-nickel compound metal layer by immersing the parting layer in a compound metal plating bath including cupric ions, nickel ions and citric acid and keeping a value of pH more than 5.0 and by plating same by means of cathodic electrolysis, and (d) immersing the copper-nickel compound metal layer in an electric plating bath to deposit a thin copper foil layer.
Claim 3
Independent Claim
212 words
A method of manufacturing a thin copper foil for a printed wiring board comprising the steps of: (a) preparing a copper foil supporter having a rough surface on at least a side thereof, said rough surface being provided with a difference of 1˜10 μm between the absolute top and bottom thereof and a thickness of 18˜100 μm, (b) forming a parting layer on the rough surface of the copper foil supporter by immersing the rough surface in a chromate bath keeping a value of pH between 2.0˜6.5 and including at least one kind of chromate compounds selected from a group of chromium trioxide, potassium dichromate and sodium dichromate at a concentration of 0.1 g/l as hexavalent chromium ions. (c) forming a copper-nickel compound metal layer having a thickness of 0.01˜0.6 μm by immersing the parting layer in a compound metal plating bath including copper sulfate (5H 2 O) of 0.04˜0.12 mole/l nickel sulfate (6H 2 O) of 0.07˜0.24 mole/l and citric acid of 0.3˜0.5 mole/l and keeping a value of pH more than 5.0, and by depositing the parting layer by means of cathodic electrolysis, and (d) immersing the copper-nickel compound metal layer in an electric copper plating bath to deposit a thin copper foil layer having a thickness of 1˜9 μm.
Claim 4
Independent Claim
212 words
A method of manufacturing a thin copper foil for a printed wiring board comprising the steps of: (a) preparing a copper foil supporter having a rough surface on at least a side thereof, said rough surface being provided with a difference of 1˜10 μm between the absolute top and bottom thereof and a thickness of 18˜100 μm, (b) forming a parting layer on the rough surface of the copper foil supporter by immersing the rough surface in a chromate bath keeping a value of pH between 2.0˜6.5 and including at least one kind of chromate compounds selected from a group of chromium trioxide, potassium dichromate and sodium dichromate at a concentration of 0.1 g/l as hexavalent chromium ions. (c) forming a copper-nickel compound metal layer having a thickness of 0.01˜0.6 μm by immersing the parting layer in a compound metal plating bath including copper sulfate (5H 2 O) of 0.04˜0.12 mole/l nickel sulfate (6H 2 O) of 0.07˜0.24 mole/l and citric acid of 0.3˜0.5 mole/l and keeping a value of pH more than 5.0, and by depositing the parting layer by means of cathodic electrolysis, and (d) immersing the copper-nickel compound metal layer in an electric copper plating bath to deposit a thin copper foil layer having a thickness of 1˜9 μm.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-05-19 | 1995-11-18 | 1996-05-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-05-19 | 1999-11-18 | 2000-05-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-05-19 | 2003-11-18 | 2004-05-19 | $7700.00 | Window Closed / Lapsed |