Patent US2578075A successfully refreshed from Google Patents.
US2578075A
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Brownprint fixing composition containing alkali thiosulfate, alkali oxalate, and a surface active wetting agent
Assignee: Keuffel and Esser Co
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Filing: 1949-06-18
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Granted: 1951-12-11
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Expires: 1969-06-18
Abstract
No abstract record available.
Inventors
- 👤 John F Kienast
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 21:18
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/64
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
47 words
AN ANHYDROUS COMPOSITION FOR FORMING A BROWNPRINT FIXING SOLUTION BY THE ADDITION OF WATER THERETO CONSISTING ESSENTIALLY OF FROM 20 TO 60% OF ANHYDROUS ALKALI THIOSULFATE, FROM 80 TO 30% OF ALKALI OXALATE AND FROM 0 TO 10% OF A DRY SURFACE ACTIVE WETTING AGENT COMPATIBLE THEREWITH.
Claim 2
Dependent Claim
47 words
AN ANHYDROUS COMPOSITION FOR FORMING A BROWNPRINT FIXING SOLUTION BY THE ADDITION OF WATER THERETO CONSISTING ESSENTIALLY OF FROM 20 TO 60% OF ANHYDROUS ALKALI THIOSULFATE, FROM 80 TO 30% OF ALKALI OXALATE AND FROM 0 TO 10% OF A DRY SURFACE ACTIVE WETTING AGENT COMPATIBLE THEREWITH.
References Cited (Backward Citations)
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US1411687A
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US1521840A
Cited
US2000353A
Cited
US1899674A
Cited
US2101834A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-12-10 | 1955-06-11 | 1955-12-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-12-10 | 1959-06-11 | 1959-12-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-12-10 | 1963-06-11 | 1963-12-11 | $7700.00 | Window Closed / Lapsed |