Patent US3954471A successfully refreshed from Google Patents.
US3954471A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Photographic fixing process
Assignee: Imperial Chemical Industries Ltd
•
Filing: 1974-09-12
•
Granted: 1976-05-04
•
Expires: 1994-09-12
Abstract
Abstract In an image recording process, a radiation sensitive film comprising a photo-reducible compound is exposed to radiation and subsequently is contacted with a fixing agent capable of being reduced by the reduction product of the photo-reducible compound, with the production of an insoluble coloured material.
Inventors
- 👤 Timothy Douglas Andrews
- 👤 Glyn David Short
- 👤 Jan Willem Frederik VAN Ingen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 19:44
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/72; G03C1/73
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
120 words
A method of forming an image, which comprises the steps of irradiating imagewise a photosensitive material containing a radiation sensitive salt of the general formula ##SPC6## where R 1 and R 2 are selected from the group consisting of alkyl, aryl, aralkyl, alkaryl and oxyhydrocarbyl groups, n is 0 or an integer and X - is an anion whereby a reduction product is formed, and contacting the irradiated salt with a solution of a water soluble fixing agent capable of being reduced to a water-insoluble colored product by the said reduction product, said fixing agent being selected from the group consisting of tetrazolium salts, phthalocyanine dye precursors and ferricyanides, for a time sufficient for the formation of such colored product.
Claim 2
Independent Claim
120 words
A method of forming an image, which comprises the steps of irradiating imagewise a photosensitive material containing a radiation sensitive salt of the general formula ##SPC6## where R 1 and R 2 are selected from the group consisting of alkyl, aryl, aralkyl, alkaryl and oxyhydrocarbyl groups, n is 0 or an integer and X - is an anion whereby a reduction product is formed, and contacting the irradiated salt with a solution of a water soluble fixing agent capable of being reduced to a water-insoluble colored product by the said reduction product, said fixing agent being selected from the group consisting of tetrazolium salts, phthalocyanine dye precursors and ferricyanides, for a time sufficient for the formation of such colored product.
Claim 3
Dependent Claim
56 words
A method according to claim 1 in which the fixing agent is a tetrazolium salt of the general formula ##EQU2## where R 3 is selected from aryl and heterocyclic groups, and A is an alkylene or arylene group and R 4 is selected from H, OH, SH, CN, COOH, carboxylic esters, alkyl, aryl and heterocyclic groups.
Claim 4
Dependent Claim
15 words
A method according to claim 1 in which the fixing agent is a phthalocyanine precursor.
Claim 5
Dependent Claim
16 words
A method according to claim 3 in which the fixing agent is a cobalt phthaloxyanine precursor.
Claim 6
Dependent Claim
34 words
A method according to claim 1 in which the fixing agent is a water soluble ferric salt in which the iron is present as a complex anion and the corresponding ferrous salt is insoluble.
Claim 7
Dependent Claim
14 words
A method according to claim 5 in which the fixing agent is ferric ferricyamide.
Claim 8
Dependent Claim
9 words
An image obtained by the method of claim 1.
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) | 1979-05-04 | 1979-11-03 | 1980-05-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-05-04 | 1983-11-03 | 1984-05-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-05-04 | 1987-11-03 | 1988-05-04 | $7700.00 | Window Closed / Lapsed |