Patent USRE32661E successfully refreshed from Google Patents.
USRE32661E
Expired / Lapsed
US
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Cleaning aluminum at low temperatures
Assignee: Henkel Corp
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Filing: 1984-07-27
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Granted: 1988-05-03
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Expires: 2004-07-27
Abstract
Abstract Acid cleaning of aluminum surfaces is accomplished employing a composition comprising hydrofluoric acid and sulfuric acid. More specifically, this invention relates to a composition and method for treating aluminum containers at low temperatures.
Inventors
- 👤 Robert E. Binns
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 23:31
CPC Classifications
C; C23; C23G; C23G1/00; C23G1/02; C23G1/12; C23G1/125
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
135 words
surfactant..]. .Iadd.7. An acidic aqueous cleaning solution having a pH of less than 2.0 and consisting essentially of about 1 to about 10 g/l of sulfuric acid, about 0.005 to about 0.1 g/l of hydrofluoric acid, and about 0.1 to about 10 g/l of a surfactant selected from the group consisting of nonionic and anionic surfactants, wherein the sources of said acids are respectively sulfuric acid and hydrofluoric acid, wherein said solution is free of a corrosion inhibitor in a corrosion-inhibiting amount and of a sludge-forming material, and wherein said solution is effective in removing and dissolving aluminum fines and in cleaning lubricating oils from the surfaces of drawn and ironed aluminum cans of 3004 alloy at a temperature within the range of about 110° F. to about 135° F., said cleaned surfaces being water-break-free.
Claim 2
Dependent Claim
181 words
.Iaddend. .Iadd.8. A cleaning solution according to claim 7 wherein the concentration of said sulfuric acid is about 3 to about 5 g/l. .Iaddend. .Iadd.9. A cleaning solution according to claim 7 wherein the concentration of said hydrofluoric acid is about 0.01 to about 0.03 g/l. .Iaddend. .Iadd.10. A cleaning solution according to claim 7 wherein the concentrations of said sulfuric and said hydrofluoric acid are respectively about 3 to about 5 g/l and about 0.01 to about 0.03 g/l. .Iaddend. .Iadd.11. A cleaning solution according to claim 7, 8, 9 or 10 wherein said pH is about 1.0 to about 1.8. .Iaddend. .Iadd.12. A cleaning solution according to claim 7, 8, 9 or 10 wherein said pH is about 1.2 to about 1.5. .Iaddend. .Iadd.13. A cleaning solution according to claim 7, 8, 9 or 10 wherein said surfactant is a nonionic surfactant. .Iaddend. .Iadd.14. A cleaning solution according to claim 13 wherein said pH is about 1.0 to about 1.8. .Iaddend. .Iadd.15. A cleaning solution according to claim 13 wherein said pH is about 1.2 to about 1.5. .Iaddend.
References Cited (Backward Citations)
CA536710A
Cited
US27662A
Cited
CA868314A
Cited
CA850046A
Cited
GB115630A
Cited
US2040618A
Cited
US2316220A
Cited
FR881701A
Cited
US2376082A
Cited
GB543770A
Cited
US2477181A
Cited
US2413365A
Cited
US2719796A
Cited
US2762694A
Cited
US2828193A
Cited
GB877240A
Cited
US3140203A
Cited
US3138485A
Cited
US3220899A
Cited
DE1202615B
Cited
US3367799A
Cited
US3275562A
Cited
US3448055A
Cited
US3510430A
Cited
US3634262A
Cited
US3728188A
Cited
USRE27662E
Cited
US3969135A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-05-03 | 1991-11-02 | 1992-05-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-05-03 | 1995-11-02 | 1996-05-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-05-03 | 1999-11-02 | 2000-05-03 | $7700.00 | Window Closed / Lapsed |