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US4426252A
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Process and composition for preparing aluminum surfaces for anodizing
Assignee: Arkema Inc
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Filing: 1983-05-09
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Granted: 1984-01-17
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Expires: 2003-05-09
Abstract
Abstract Aluminum is cleaned and etched prior to anodizing using solutions containing dilute hexafluorophosphoric acid and, optionally, nitric acid.
Inventors
- 👤 James M. Kape
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 03:50
CPC Classifications
C; C23; C23F; C23F1/00; C23F1/10; C23F1/14; C23F1/16; C23F1/20
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
22 words
A process for etching aluminum alloys to provide a matte surface comprising contacting the surface with an aqueous solution containing hexafluorophosphoric acid.
Claim 2
Dependent Claim
22 words
A process for etching aluminum alloys to provide a matte surface comprising contacting the surface with an aqueous solution containing hexafluorophosphoric acid.
Claim 3
Dependent Claim
18 words
The process of claim 1 wherein the solution contains at least about 0.5% by volume of hexafluorophosphoric acid.
Claim 4
Dependent Claim
19 words
The process of claim 2 wherein the solution contains from about 0.5 to 5.0% by volume of hexafluorophosphoric acid.
Claim 5
Dependent Claim
37 words
The process of claim 1 wherein the solution is at a temperature of from about 10° C. to 70° C. and the surface is contacted with the solution for from about 30 seconds to about 30 minutes.
Claim 6
Dependent Claim
11 words
The process of claim 1 wherein the solution contains nitric acid.
Claim 7
Dependent Claim
19 words
The process of claim 5 wherein the solution contains from about 0.5 to 2.5% by volume of nitric acid.
Claim 8
Dependent Claim
35 words
The process of claim 1 wherein the solution is at a temperature of about 20° C. to 60° C. and the surface is contacted with the solution for from about 30 seconds to 30 minutes.
Claim 9
Dependent Claim
14 words
An etching composition comprising a dilute aqueous solution of hexafluorophosphoric acid and nitric acid.
Claim 10
Dependent Claim
14 words
An etching composition comprising a dilute aqueous solution of hexafluorophosphoric acid and nitric acid.
Claim 11
Dependent Claim
29 words
The etching composition of claim 8 wherein the solution contains at least about 0.5% by volume of hexafluorophosphoric acid and at least about 0.5% by volume of nitric acid.
Claim 12
Dependent Claim
31 words
The etching composition of claim 8 wherein the solution contains from about 0.5 to 5.0% by volume of hexafluorophosphoric acid and from about 0.5 to 2.5% by volume of nitric acid.
References Cited (Backward Citations)
US2729551A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-01-16 | 1987-07-18 | 1988-01-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-01-16 | 1991-07-18 | 1992-01-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-01-16 | 1995-07-18 | 1996-01-17 | $7700.00 | Window Closed / Lapsed |