US3896256A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for improving the solderability of a stainproofed copper surface and product
Assignee: Circuit Foil USA Inc
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Filing: 1972-12-01
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Granted: 1975-07-22
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Expires: 1992-12-01
Abstract
Abstract A process for processing a stainproofed copper foil surface to improve solderability by coating the surface with a compound which will react with the stainproofing coating to expose the copper to the solder. The processed copper foil so produced and laminates including such foil.
Inventors
- 👤 Adam M Wolski
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 20:57
CPC Classifications
B; B23; B23K; B23K35/00; B23K35/22; B23K35/36; B23K35/3601; B23K35/3603; B23K35/226; H; H05; H05K; H05K3/00; H05K3/22; H05K3/28; H05K3/282; H05K3/38; H05K3/382; H05K3/385; H05K2201/00; H05K2201/03; H05K2201/0332; H05K2201/0335; H05K2201/0355; H05K2203/00; H05K2203/03; H05K2203/0315; H05K2203/11; H05K2203/1157; Y; Y10; Y10T; Y10T428/00; Y10T428/12; Y10T428/12493; Y10T428/12771; Y10T428/12861; Y10T428/12903; Y10T428/12986; Y10T428/31504; Y10T428/31678
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
79 words
A CONTINUOUS PROCESS FOR TREATING COPPER FOIL COMPRISING THE STEPS OF: STAINPROOFING THE COPPER FORL IMMEERING THE COPPER FOIL IN AN AQUEOUS ELECTROLYTE CONTAINING HEXAVALENT CHROMINUM ION-CONTAINING ANIONS AND RENDERING SAID COPPER FOIL CATHODIC TO PRODUCE A STAINPROOFED SURFACE, SAID AQUEOUS ELECTROLYTE BEING SUFFICENTLY ALKALINE TO CAUSE PRECIPTATION OF COPPER AND CHROME CATIONS, COATING THE STAINPROOFED SURFACE WITH A COMPOUND WHICH, AT SOLDERING TEMPERATURES, WILL REACT WITH THE STAINPROOFING COATING TO EXPOSE THE COPPER, AND DRYING THE STAINPROOFED SURFACE.
Claim 2
Dependent Claim
79 words
A CONTINUOUS PROCESS FOR TREATING COPPER FOIL COMPRISING THE STEPS OF: STAINPROOFING THE COPPER FORL IMMEERING THE COPPER FOIL IN AN AQUEOUS ELECTROLYTE CONTAINING HEXAVALENT CHROMINUM ION-CONTAINING ANIONS AND RENDERING SAID COPPER FOIL CATHODIC TO PRODUCE A STAINPROOFED SURFACE, SAID AQUEOUS ELECTROLYTE BEING SUFFICENTLY ALKALINE TO CAUSE PRECIPTATION OF COPPER AND CHROME CATIONS, COATING THE STAINPROOFED SURFACE WITH A COMPOUND WHICH, AT SOLDERING TEMPERATURES, WILL REACT WITH THE STAINPROOFING COATING TO EXPOSE THE COPPER, AND DRYING THE STAINPROOFED SURFACE.
Claim 3
Dependent Claim
9 words
The product produced by the process of claim 1.
Claim 4
Dependent Claim
15 words
The process of claim 1 wherein the aqueous electrolyte has a pH of approximately 14.
Claim 5
Dependent Claim
9 words
The product produced by the method of claim 3.
Claim 6
Dependent Claim
25 words
The process of claim 1 wherein said compound generates a halogen acid at a soldering temperature within the range of about 450*F to about 560*F.
Claim 7
Dependent Claim
9 words
The product produced by the process of claim 5.
Claim 8
Dependent Claim
30 words
The process of claim 1 wherein said compound is substantially inert with respect to the stainproofing coating at a laminating temperature within the range of about 200*F to about 350*F.
Claim 9
Dependent Claim
9 words
The product produced by the process of claim 7.
Claim 10
Dependent Claim
26 words
The process of claim 7 wherein a sufficient vapor pressure of halogen acid is generated by said compound at said laminating temperature to reduce oxide stains.
Claim 11
Dependent Claim
11 words
The process of claim 1 wherein said compound is ammonium chloride.
Claim 12
Dependent Claim
9 words
The product produced by the process of claim 10.
Claim 13
Dependent Claim
37 words
The process of claim 10 wherein said ammonium chloride is applied in the form of an aqueous solution containing an amount of said ammonium chloride within the range of from about 0.2 grams/liter to about 0.8 grams/liter.
Claim 14
Dependent Claim
9 words
The product produced by the method of claim 12.
Claim 15
Dependent Claim
39 words
The process of claim 1 further comprising laminating the surface of the copper foil opposite the surface coated with said compound to an inert substrate and then applying solder to the surface of the foil coated with said compound.
Claim 16
Dependent Claim
31 words
The process of claim 14 wherein said compound is substantially inert with respect to the stainproofing coating at a laminating temperature within the range of from about 200*F to about 350*F.
Claim 17
Dependent Claim
9 words
The product produced by the process of claim 15.
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) | 1978-07-21 | 1979-01-20 | 1979-07-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-07-21 | 1983-01-20 | 1983-07-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-07-21 | 1987-01-20 | 1987-07-22 | $7700.00 | Window Closed / Lapsed |