Patent US4587915A successfully refreshed from Google Patents.
Patent US2872277A successfully refreshed from Google Patents.
US2872277A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dyeing of leather
Assignee: GAF Chemicals Corp
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Filing: 1955-12-29
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Granted: 1959-02-03
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Expires: 1975-12-29
Abstract
No abstract record available.
Inventors
- 👤 Joseph S Kirk
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 12:40
CPC Classifications
D; D06; D06P; D06P3/00; D06P3/02; D06P3/04; D06P3/32; D06P3/3246
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
67 words
A PROCESS FOR COLORING LEATHER COMPRISING SPRAYING THE LEATHER WITH AN AQUEOUS BATH CONTAINING A SULFURIC ACID ESTER SALT OF A LEUCO VAT DYESTUFF, AN AGENT SELECTED FORM THE GROUP CONSISTING OF WATER-SOLUBLE ANIOMIC AND NON-IONIC SURFACE ACTIVE AGENTS, A MEMBER OF THE GROUP CONSISTING OF N-LOWER ALKYL-2-PYRROLIDONES, N,N-DIMETHYLFORMAMIDE, N, N-DIETHYLFORMAMIDE, AND N, N-DIHYDROXYETHYLFORMAMIDE, AND SODIUM NITRITE, AND THEN TREATING THE SPRAYED LEATHER WITH AN ACID SOLUTION.
Claim 2
Dependent Claim
67 words
A PROCESS FOR COLORING LEATHER COMPRISING SPRAYING THE LEATHER WITH AN AQUEOUS BATH CONTAINING A SULFURIC ACID ESTER SALT OF A LEUCO VAT DYESTUFF, AN AGENT SELECTED FORM THE GROUP CONSISTING OF WATER-SOLUBLE ANIOMIC AND NON-IONIC SURFACE ACTIVE AGENTS, A MEMBER OF THE GROUP CONSISTING OF N-LOWER ALKYL-2-PYRROLIDONES, N,N-DIMETHYLFORMAMIDE, N, N-DIETHYLFORMAMIDE, AND N, N-DIHYDROXYETHYLFORMAMIDE, AND SODIUM NITRITE, AND THEN TREATING THE SPRAYED LEATHER WITH AN ACID SOLUTION.
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) | 1962-02-02 | 1962-08-04 | 1963-02-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-02-02 | 1966-08-04 | 1967-02-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-02-02 | 1970-08-04 | 1971-02-03 | $7700.00 | Window Closed / Lapsed |