US3620940A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of inducing polarization of active magnesium surfaces
Assignee: United States Department of the Army
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Filing: 1970-05-12
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Granted: 1971-11-16
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Expires: 1990-05-12
Abstract
Abstract Methods for surface polarizing magnesium and its alloys; thus permitting large pieces to be readily anodized using only nominal electric power. Low adhesion, easily strippable film strips are adhered to the pieces, the strips providing areas of exposed metal which allow a high current density to be built up thereat which produces vigorous electrolytic action for progressively peeling off the films for subsequent anodization of the pieces.
Inventors
- 👤 Reyburn Wick
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 22:42
CPC Classifications
C; C25; C25D; C25D11/00; C25D11/02; C25D11/30
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
20 words
The method as described in claim 1 further characterized by cleaning said pieces prefatory to adhering said strippable films thereto.
Claim 2
Dependent Claim
25 words
The method as described in claim 1 wherein adhering said strippable film comprises the step of brushing spaced bands of film material onto said pieces.
Claim 3
Dependent Claim
42 words
The method as described in claim 1 wherein adhering said strippable film comprises the steps of dipping said pieces into strippable film material and then providing spaced areas of exposed metal on said pieces by removing selected portions of said dipped film.
Claim 4
Dependent Claim
42 words
The method as described in claim 1 wherein adhering said strippable film comprises the steps of spraying said pieces with strippable film material and then providing spaced areas of exposed metal on said pieces by removing selected portions of said sprayed film.
Claim 5
Dependent Claim
61 words
The method as described in claim 1 wherein said strippable film comprises: Cellulose acetate butyrate; (maximum free acidity, as acetic acid 0.02%) 56 g. Chlorinated biphenyl 52 g. Polyethylene glycol di-2-ethyl-hexanoate 12 g. Mineral oil 8 g. Xylol 167 ml. Isopropanol 82.3 ml. Phenylsalicylate 1 g. Trilauryl phosphate1 g. Di2-ethyl hexylamine or methyl morpholine 1 ml. Solubilized 10% copper-8-quinolinolate 0.75 ml.
Claim 6
Dependent Claim
21 words
The method as described in claim 1 wherein said magnesium alloy is selected from the group consisting of AZ31 and AZ91.
Claim 7
Dependent Claim
25 words
The method as described in claim 1 wherein said masked surfaces comprises about 80 to 90 percent of the total surface area of said pieces.
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) | 1974-11-15 | 1975-05-17 | 1975-11-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-11-15 | 1979-05-17 | 1979-11-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-11-15 | 1983-05-17 | 1983-11-16 | $7700.00 | Window Closed / Lapsed |