US4976829A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Coating substrates
Assignee: BTG International Ltd
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Filing: 1989-10-17
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Granted: 1990-12-11
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Expires: 2009-10-17
Abstract
Abstract A metallic container for beverage is protected from its contents by electrodeposited zinc, which is anodized in alkali then anodically reacted with weak poly(acrylic acid) and finally cured at 85° C. at 100% relative humidity.
Inventors
- 👤 John Ellis
- 👤 John W. Nicholson
- 👤 Alan D. Wilson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 03:43
CPC Classifications
C; C25; C25D; C25D11/00; C25D11/02; C25D11/34
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
58 words
A process for producing a coherent protective layer on a metallic surface, said process comprising the steps of: forming a layer of tin oxide on the metallic surface; and reacting the tin oxide layer with an aqueous solution of a homo- or copolymer of polyacrylic acid) or even more highly carboxylated unsaturated-carbon-backbone acid or a hydrolyzable precursor thereof.
Claim 2
Dependent Claim
58 words
A process for producing a coherent protective layer on a metallic surface, said process comprising the steps of: forming a layer of tin oxide on the metallic surface; and reacting the tin oxide layer with an aqueous solution of a homo- or copolymer of polyacrylic acid) or even more highly carboxylated unsaturated-carbon-backbone acid or a hydrolyzable precursor thereof.
Claim 3
Dependent Claim
17 words
A process according to claim 1, wherein said tin oxide layer is deposited on the surface electrochemically.
Claim 4
Dependent Claim
13 words
A process according to claim 1, wherein said tin oxide is formed anodically.
Claim 5
Dependent Claim
18 words
A process according to claim 2, wherein said tin oxide is formed anodically in the presence of borate.
Claim 6
Dependent Claim
14 words
A process according to claim 2, wherein the electrolysis continues for under one minute.
Claim 7
Dependent Claim
15 words
A process according to claim 1, wherein the acid has a concentration of under 5%.
Claim 8
Dependent Claim
12 words
A process according to claim 6, wherein said concentration is under 1%.
Claim 9
Dependent Claim
31 words
A process according to claim 1, wherein the deposit with acid is cured from 80° C. to 100° C. for from 10 to 60 minutes at at least 80% relative humidity.
References Cited (Backward Citations)
US2215165A
Cited
GB2173805A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-12-10 | 1994-06-11 | 1994-12-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-12-10 | 1998-06-11 | 1998-12-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-12-10 | 2002-06-11 | 2002-12-11 | $7700.00 | Window Closed / Lapsed |