US3878006A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Selective etchant for nickel/phosphorus alloy
Assignee: Mica Corp
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Filing: 1973-10-26
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Granted: 1975-04-15
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Expires: 1993-10-26
Abstract
Abstract A novel etching composition for the selective removal of resistive nickel or nickel alloy which comprises: CuSO4 . 5H2O - 0.5 M to 1.5 M H2SO4 (conc.) - 0.02 M to 2 M In the processing of a novel printed circuit board material in the form of a multilayer stock comprising an insulating support, at least one layer of a nickel or nickel alloy resistance material adhering to said support, and a layer of a highly conductive copper adhering to the resistance material and in intimate contact therewith, the improvement wherein the combined conductor and resistor patterns are formed thereon using a resist, the laminate is etched leaving a resistor surface over the unresisted areas and the unwanted resistor layer is then selectively etched using an etchant comprising: CuSO4 . 5H2O - 0.5 M to 1.5 M H2504 (conc.) - 0.02 M to 2 M
Inventors
- 👤 James M Rice
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 10:49
CPC Classifications
C; C23; C23F; C23F1/00; C23F1/10; C23F1/14; C23F1/16; C23F1/28; C23F1/02; C23F1/44; H; H05; H05K; H05K1/00; H05K1/16; H05K1/167; H05K3/00; H05K3/02; H05K3/06; H05K3/067
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
28 words
A NOVEL ETCHING COMPOSITION FOR THE SELECTIVE REMOVAL OF RESISTIVE NICKEL OR NICKEL ALLOY IN THE PRESENCE OF COPPER WHICH COMPRISES: CUSO4.5H2O-0.5M TO 1.5M H2SO4 (CONC.)-0.02M TO 2M
Claim 2
Dependent Claim
28 words
A NOVEL ETCHING COMPOSITION FOR THE SELECTIVE REMOVAL OF RESISTIVE NICKEL OR NICKEL ALLOY IN THE PRESENCE OF COPPER WHICH COMPRISES: CUSO4.5H2O-0.5M TO 1.5M H2SO4 (CONC.)-0.02M TO 2M
Claim 3
Dependent Claim
32 words
A novel etching composition for the selective removal of resistive nickel or nickel alloy in the presence of copper which comprises: CuSO4 . 5H2O - 250 gm/liter H2SO4 (conc.) - 2 ml/liter
Claim 4
Dependent Claim
32 words
A novel etching composition for the selective removal of resistive nickel or nickel alloy in the presence of copper which comprises: CuSO4 . 5H2O - 250 gm/liter H2SO4 (conc.) - 2 ml/liter
Claim 5
Dependent Claim
110 words
The processing of a novel printed circuit board material in the form of a multilayer stock comprising an insulating support, at least one layer of nickel or a nickel alloy resistance material adhering to said support, and a layer of highly conductive copper adhering to the resistance material and in intimate contact therewith, the improvement wherein the combined conductor and resistor patterns are formed thereon using a resist, the laminate is etched leaving a resistor surface over the unresisted areas, and the unwanted resistor layer is then selectively etched using an etchant comprising: CuSO4 . 5H2O - 0.5 M to 1.5 M H2SO4 (conc.) - 0.02 M to 2 M
Claim 6
Dependent Claim
110 words
The processing of a novel printed circuit board material in the form of a multilayer stock comprising an insulating support, at least one layer of nickel or a nickel alloy resistance material adhering to said support, and a layer of highly conductive copper adhering to the resistance material and in intimate contact therewith, the improvement wherein the combined conductor and resistor patterns are formed thereon using a resist, the laminate is etched leaving a resistor surface over the unresisted areas, and the unwanted resistor layer is then selectively etched using an etchant comprising: CuSO4 . 5H2O - 0.5 M to 1.5 M H2SO4 (conc.) - 0.02 M to 2 M
Claim 7
Dependent Claim
22 words
The processing of claim 3 wherein the unwanted resistor layer is selectively etched at a temperature of from about 130*F. to 200*F.
Claim 8
Dependent Claim
20 words
The processing of claim 3 wherein said etchant comprises: CuSO4 . 5H2O - 250 gm/liter H2SO4 (conc.) - 2 ml/liter
Claim 9
Dependent Claim
22 words
The processing of claim 5 wherein the unwanted resistor layer is selectively etched at a temperature of from about 130*F. to 200*F.
Claim 10
Dependent Claim
13 words
The processing of claim 3 wherein said resistance material is a nickel-phosphorus alloy.
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) | 1978-04-14 | 1978-10-14 | 1979-04-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-14 | 1982-10-14 | 1983-04-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-14 | 1986-10-14 | 1987-04-15 | $7700.00 | Window Closed / Lapsed |