US2564238A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Silver azo dye bleach-out process and bleaching baths for use therein
Assignee: GAF Chemicals Corp
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Filing: 1946-12-14
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Granted: 1951-08-14
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Expires: 1966-12-14
Abstract
No abstract record available.
Inventors
- 👤 Joseph A Sprung
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 18:20
CPC Classifications
G; G03; G03C; G03C7/00; G03C7/28
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
107 words
IN THE PROCESS OF PRODUCING DYESTUFF IMAGES IN A PHOTOGRAPHIC ELEMENT BY THE IMAGEWISE DESTRUCTION OF AN AZO DYE AT THE SILVER IMAGE OF SUCH ELEMENT, THE IMPROVEMENT WHICH COMPRISES EFFECTING, SUCH DYE DESTRUCTION WITH AN AQUEOUS BLEACH-OUT BATH CONTAINING AS ITS ESSENTIAL COMPONENTS A SILVER SALT FORMER CONSISTING OF A WATER SOLUBLE INORGANIC HALIDE, A SILVER COMPLEX FORMER INCAPABLE OF REVERSIBLE OXIDATION AND REDUCTION CONSISTING OF A HETEROCYCLIC NITROGENEOUS BASE IN WHICH THE HETEROCYCLIC N IS UNSUBSTITUTED AND WHICH IS SELECTED FROM THE CLASS CONSISTING OF QUINOLINES AND ISOQUIONOLINES AND A SUFFICIENT QUANTITY OF AN ACID TO PROVIDE THE BLEACH-OUT BATH WITH A PH BELOW 7.
Claim 2
Dependent Claim
107 words
IN THE PROCESS OF PRODUCING DYESTUFF IMAGES IN A PHOTOGRAPHIC ELEMENT BY THE IMAGEWISE DESTRUCTION OF AN AZO DYE AT THE SILVER IMAGE OF SUCH ELEMENT, THE IMPROVEMENT WHICH COMPRISES EFFECTING, SUCH DYE DESTRUCTION WITH AN AQUEOUS BLEACH-OUT BATH CONTAINING AS ITS ESSENTIAL COMPONENTS A SILVER SALT FORMER CONSISTING OF A WATER SOLUBLE INORGANIC HALIDE, A SILVER COMPLEX FORMER INCAPABLE OF REVERSIBLE OXIDATION AND REDUCTION CONSISTING OF A HETEROCYCLIC NITROGENEOUS BASE IN WHICH THE HETEROCYCLIC N IS UNSUBSTITUTED AND WHICH IS SELECTED FROM THE CLASS CONSISTING OF QUINOLINES AND ISOQUIONOLINES AND A SUFFICIENT QUANTITY OF AN ACID TO PROVIDE THE BLEACH-OUT BATH WITH A PH BELOW 7.
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) | 1954-08-13 | 1955-02-12 | 1955-08-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-08-13 | 1959-02-12 | 1959-08-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-08-13 | 1963-02-12 | 1963-08-14 | $7700.00 | Window Closed / Lapsed |