US3941627A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of producing tarnish resistant copper and copper alloys and products thereof
Assignee: Olin Corp
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Filing: 1973-03-26
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Granted: 1976-03-02
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Expires: 1993-03-26
Abstract
Abstract The instant invention comprises providing copper or a copper alloy which has on its surface a uniform glassy like and substantially pore free coating of copper phosphate, rinsing the coated material for at least two seconds in water at a pH of at least 8.0, at a temperature of 90°C to the boiling point and drying.
Inventors
- 👤 Elmer J. Caule
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 23:42
CPC Classifications
B; B32; B32B; B32B15/00; B32B15/04; B32B15/08; C; C23; C23C; C23C22/00; C23C22/05; C23C22/06; C23C22/24; C23C22/33; C23C22/78; C23C22/82; C23C22/83; G; G03; G03C; G03C1/00; G03C1/76; H; H05; H05K; H05K3/00; H05K3/38; H05K3/382; H05K3/385; H05K1/00; H05K1/02; H05K1/03; H05K1/0393; H05K2201/00; H05K2201/03; H05K2201/0332; H05K2201/0335; H05K2201/0355; H05K2203/00; H05K2203/03; H05K2203/0315
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
143 words
A method of producing a flexible printed circuit comprising: A. providing a material selected from the group consisting of copper foil and copper sheet, B. applying to a surface of said material a phosphoric acid solution of at least 8% concentration and containing from 3.5 grams per liter up to the solubility limit of a material selected from the group consisting of sodium dichromate and potassium dichromate and mixtures thereof, for at least 2 seconds, to form a uniform, glassy-like, substantially porefree coating of copper phosphate from 20 to 1,000 Angstroms thick, provided that when the concentration of phosphoric acid is increased, the minimum dichromate concentration is proportionately increased. C. rinsing said material for at least two seconds in water at a pH of at least 8.0 and at a temperature from about 90°C up to the boiling point, D. drying said material,
Claim 2
Independent Claim
143 words
A method of producing a flexible printed circuit comprising: A. providing a material selected from the group consisting of copper foil and copper sheet, B. applying to a surface of said material a phosphoric acid solution of at least 8% concentration and containing from 3.5 grams per liter up to the solubility limit of a material selected from the group consisting of sodium dichromate and potassium dichromate and mixtures thereof, for at least 2 seconds, to form a uniform, glassy-like, substantially porefree coating of copper phosphate from 20 to 1,000 Angstroms thick, provided that when the concentration of phosphoric acid is increased, the minimum dichromate concentration is proportionately increased. C. rinsing said material for at least two seconds in water at a pH of at least 8.0 and at a temperature from about 90°C up to the boiling point, D. drying said material,
Claim 3
Dependent Claim
74 words
E. adhesively laminating a plastic film to said surface, F. applying a photoresist to the opposing surface of said material, G. projecting a circuitry pattern upon said photoresist wherein said photoresist is transformed into an acid insoluble compound at said circuitry pattern, H. dissolving away the unwanted portion of said material from said circuitry pattern by an acid solution, I. rinsing said surface, and J. drying said surface, thereby forming a flexible printed circuit.
Claim 4
Dependent Claim
74 words
E. adhesively laminating a plastic film to said surface, F. applying a photoresist to the opposing surface of said material, G. projecting a circuitry pattern upon said photoresist wherein said photoresist is transformed into an acid insoluble compound at said circuitry pattern, H. dissolving away the unwanted portion of said material from said circuitry pattern by an acid solution, I. rinsing said surface, and J. drying said surface, thereby forming a flexible printed circuit.
Claim 5
Dependent Claim
64 words
A method according to claim 1 wherein said water is adjusted to said pH with a compound selected from the group consisting of the basic reaction salts of the alkali metals, the basic reaction salts of the alkaline earth metals, the hydroxides of the alkali metals, the hydroxides of the alkaline earth metals, ammonium salts with a basic reaction, ammonium hydroxide and mixtures thereof.
Claim 6
Dependent Claim
20 words
A method according to claim 2 wherein said compound is calcium hydroxide and said pH is from 8.0 to 11.0.
Claim 7
Dependent Claim
22 words
A method according to claim 2 wherein said plastic film is selected from the group consisting of the polyesters and the polyimides.
Claim 8
Dependent Claim
25 words
A method according to claim 1 wherein following step B and prior to step C said material is rinsed in water with the pH unadjusted.
Claim 9
Dependent Claim
19 words
A method according to claim 1 wherein following step D and before step E said material is recrystallized annealed.
Claim 10
Independent Claim
180 words
A method of producing a flexible printed circuit comprising: A. providing a material selected from the group consisting of copper foil and copper sheet, B. oxidizing a surface of said material to form a surface oxide film from 150 to 1,000 Angstrom units in thickness, C. applying a phosphoric acid solution of at least 8% concentration to said oxide film to form thereon a uniform, glassy-like, substantially porefree coating of copper phosphate, D. rinsing said material for at least two seconds in water at a pH of at least 8.0 and at a temperature from about 90°C up to the boiling point, E. drying said material, F. adhesively laminating a plastic film to said surface, G. applying a photoresist to the opposing surface of said material, H. projecting a circuitry pattern upon said photoresist wherein said photoresist is transformed into an acid insoluble compound at said circuitry pattern, I. dissolving away the unwanted portion of said material from said circuitry pattern by an acid solution, J. rinsing said surface, and K. drying said surface, thereby forming a flexible printed circuit.
Claim 11
Independent Claim
180 words
A method of producing a flexible printed circuit comprising: A. providing a material selected from the group consisting of copper foil and copper sheet, B. oxidizing a surface of said material to form a surface oxide film from 150 to 1,000 Angstrom units in thickness, C. applying a phosphoric acid solution of at least 8% concentration to said oxide film to form thereon a uniform, glassy-like, substantially porefree coating of copper phosphate, D. rinsing said material for at least two seconds in water at a pH of at least 8.0 and at a temperature from about 90°C up to the boiling point, E. drying said material, F. adhesively laminating a plastic film to said surface, G. applying a photoresist to the opposing surface of said material, H. projecting a circuitry pattern upon said photoresist wherein said photoresist is transformed into an acid insoluble compound at said circuitry pattern, I. dissolving away the unwanted portion of said material from said circuitry pattern by an acid solution, J. rinsing said surface, and K. drying said surface, thereby forming a flexible printed circuit.
Claim 12
Dependent Claim
64 words
A method according to claim 7 wherein said water is adjusted to said pH with a compound selected from the group consisting of the basic reaction salts of the alkali metals, the basic reaction salts of the alkaline earth metals, the hydroxides of the alkali metals, the hydroxides of the alkaline earth metals, ammonium salts with a basic reaction, ammonium hydroxide and mixtures thereof.
Claim 13
Dependent Claim
20 words
A method according to claim 8 wherein said compound is calcium hydroxide and said pH is from 8.0 to 11.0.
Claim 14
Dependent Claim
22 words
A method according to claim 8 wherein said plastic film is selected from the group consisting of the polyesters and the polyimides.
Claim 15
Dependent Claim
25 words
A method according to claim 7 wherein following step C and prior to step D said material is rinsed in water with the pH unadjusted.
Claim 16
Dependent Claim
19 words
A method according to claim 7 wherein following step E and before step F said material is recrystallized annealed.
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) | 1979-03-02 | 1979-09-01 | 1980-03-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-03-02 | 1983-09-01 | 1984-03-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-03-02 | 1987-09-01 | 1988-03-02 | $7700.00 | Window Closed / Lapsed |