Patent US3640713A successfully refreshed from Google Patents.
US3640713A
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Photographic processes and compositions therefor
Assignee: Polaroid Corp
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Filing: 1968-10-30
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Granted: 1972-02-08
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Expires: 1988-10-30
Abstract
Abstract Tertiary organic phosphines containing a hydroxyl and/or an amino-substituted phenyl group are used as silver halide developing agents in photographic processing compositions which find particular utility in diffusion transfer photographic techniques.
Inventors
- 👤 Sheldon A Buckler
- 👤 Ronald F Lambert
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 22:05
CPC Classifications
G; G03; G03C; G03C5/00; G03C5/26; G03C5/29; G03C5/30; G03C5/3021; G03C8/00; G03C8/02; G03C8/04; G03C8/06
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
22 words
A composition as defined in claim 1 wherein m is 2 and said R groups are in para position to each other.
Claim 2
Dependent Claim
13 words
A composition as defined in claim 1 wherein said developing agent is 2,5-dihydroxyphenyl-bis(diphenyl)-phosphine.
Claim 3
Independent Claim
75 words
A method of developing a silver halide emulsion which comprises treating an exposed silver halide emulsion containing a latent image with an aqueous solution containing a silver halide developing agent selected from the group consisting of compounds within the formula wherein Z is a monovalent hydrocarbon radical, substituted or unSubstituted; R is selected from a hydroxyl group and an amino group; m is at least 1; and n is an integer 0, 1 or 2.
Claim 4
Dependent Claim
21 words
A method according to claim 4 wherein m is 2 and said R groups are in para position to each other.
Claim 5
Dependent Claim
12 words
A method according to claim 4 wherein said developing agent is 2,5-dihydroxyphenyl-bis(diphenyl)phosphine.
Claim 6
Dependent Claim
101 words
A photographic process comprising the steps of developing an exposed silver halide emulsion with an aqueous solution comprising a silver halide developing agent and a silver halide solvent in the presence of an image-receiving material superposed on said silver halide emulsion to form a silver transfer print on said image-receiving material, said developing agent being selected from the group consisting of compounds represented by the formula wherein Z is a monovalent hydrocarbon radical, substituted or unsubstituted; R is selected from a hydroxyl group and an amino group; m is at least 1; and n is an integer 0, 1 or 2.
Claim 7
Dependent Claim
12 words
A process according to claim 7 wherein said developing agent is 2,5-dihydroxyphenyl-bis(diphenyl)phosphine.
Claim 8
Dependent Claim
16 words
A composition as defined in claim 2 wherein both of said R groups are hydroxyl groups.
Claim 9
Dependent Claim
15 words
A method according to claim 5 wherein both of said R groups are hydroxyl groups.
Claim 10
Dependent Claim
23 words
A process according to claim 7 wherein m is 2 and said R groups are hydroxyl groups in para position to each other.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-02-07 | 1975-08-09 | 1976-02-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-02-07 | 1979-08-09 | 1980-02-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-02-07 | 1983-08-09 | 1984-02-08 | $7700.00 | Window Closed / Lapsed |