US2543086A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of preparing dustless photographic fixing powders
Assignee: Eastman Kodak Co
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Filing: 1947-11-22
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Granted: 1951-02-27
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Expires: 1967-11-22
Abstract
No abstract record available.
Inventors
- 👤 Edwin S Wiitala
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 11:37
CPC Classifications
G; G03; G03C; G03C5/00; G03C5/26; G03C5/38; G03C5/386
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
86 words
THE METHOD OF FORMING A SUBSTANTIALLY ANHYDROUS DUST-FREE PHOTOGRAPHIC FIXING POWDER WHICH COMPRISES THOROUGHLY MIXING 5 PARTS BORIC ACID, 10 PARTS ANHYDROUS SODIUM BISULFITE, 147 PARTS ANHYDROUS SODIUM THIOSULFATE, 22.5 PARTS ANHYDROUS SODIUM ACETATE, 22.5 PARTS POTASSIUM ALUM, 20 PARTS SODIUM THIOSULFATE PENTAHYDRATE, SAID INGREDIENTS BEING IN POWDERED FORM AND COMPRISING RELATIVELY LARGE PARTICLES AND RELATIVELY MINUTE DUST-LIKE PARTICLES AND THEN HEATING THE MIXTURE TO RELEASE THE WATER OF HYDRATION WHEREBY THE DUST-LIKE PARTICLES IN THE COMPOSITION ARE BOUND TO THE LARGER PARTICLES OF THE POWDER.
Claim 2
Independent Claim
86 words
THE METHOD OF FORMING A SUBSTANTIALLY ANHYDROUS DUST-FREE PHOTOGRAPHIC FIXING POWDER WHICH COMPRISES THOROUGHLY MIXING 5 PARTS BORIC ACID, 10 PARTS ANHYDROUS SODIUM BISULFITE, 147 PARTS ANHYDROUS SODIUM THIOSULFATE, 22.5 PARTS ANHYDROUS SODIUM ACETATE, 22.5 PARTS POTASSIUM ALUM, 20 PARTS SODIUM THIOSULFATE PENTAHYDRATE, SAID INGREDIENTS BEING IN POWDERED FORM AND COMPRISING RELATIVELY LARGE PARTICLES AND RELATIVELY MINUTE DUST-LIKE PARTICLES AND THEN HEATING THE MIXTURE TO RELEASE THE WATER OF HYDRATION WHEREBY THE DUST-LIKE PARTICLES IN THE COMPOSITION ARE BOUND TO THE LARGER PARTICLES OF THE POWDER.
References Cited (Backward Citations)
US1753059A
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US2074200A
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US2101834A
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US2378248A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-02-26 | 1954-08-28 | 1955-02-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-02-26 | 1958-08-28 | 1959-02-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-02-26 | 1962-08-28 | 1963-02-27 | $7700.00 | Window Closed / Lapsed |