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US2872277A Expired / Lapsed US ⏱️ 0.0 years remaining

Dyeing of leather

Assignee: GAF Chemicals Corp
•
Filing: 1955-12-29
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Granted: 1959-02-03
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Expires: 1975-12-29
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Abstract

No abstract record available.

Inventors

  • 👤 Joseph S Kirk

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 09:50
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)

US1826352A Cited
US2117699A Cited
US2150389A Cited
US2432041A Cited
BE493944A Cited

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

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