Patent US2921858A successfully refreshed from Google Patents.
US2921858A
Expired / Lapsed
US
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Process and composition for treating metal to increase corrosion resistance
Assignee: Henkel Corp
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Filing: 1957-04-30
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Granted: 1960-01-19
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Expires: 1977-04-30
Abstract
No abstract record available.
Inventors
- 👤 Wilbur S Hall
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 13:06
CPC Classifications
B; B32; B32B; B32B15/00; B32B15/04; B32B15/08; C; C23; C23C; C23C22/00; C23C22/05; C23C22/60
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
130 words
A METAL COATING BATH CONSISTING ESSENTIALLY OF WATER, A VOLATILE AKLALI, RESIN AND WATER-SOLUBLE HEXAVALENT CHROMIUM WHEREIN THE QUANTITY OF VOLATILE ALKALI PRESENT IS SUFFICIENT TO YIELD A PH OF AT LEAST 7, THE QUANTITY OF RESIN IS AT LEAST 3% (WEIGHT/VOLUME I.E., GRAMS PER 100 ML.) OF THE SOLUTION, AND THE CONCENTRATION OF HEXAVALENT CHROMIUM (CALCULATED AS CRO3) IS AT LEAST 2 GRAMS PER LITER BUT INSUFFICIENT TO PRECIPITATE THE RESIN, THE RESIN BEING CHOSEN FROM THE CLASS WHICH CONSISTS OF SHELLAC, VINYL ACETATE-CROTONIC ACID COPOLYMERS, VINLY ACETATEMALEIC ANHYDRIDE COPOLYMERS, VINLY ACETATE-PHTHALIC ANHYDRIDE COPOLYMERS VINLY ACETATE-ACREYLIC ACID COPOLYMERS, VINLY ACETATE-METHACRYLIC ACID COPOLYMERS AND STYRENE-CROTONIC ACID COPOLYMERS, AND THE HEXAVALENT CHROMIUM BEING CHOSEN FROM THE GROUP WHICH CONSISTS OF CHROMIC ACID AND SODIUM, POTASSIUM, AMMONIUM AND MORPHOLINE CHROMATE AND DICHROMATE.
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) | 1963-01-18 | 1963-07-20 | 1964-01-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-01-18 | 1967-07-20 | 1968-01-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-01-18 | 1971-07-20 | 1972-01-19 | $7700.00 | Window Closed / Lapsed |