US4067740A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Trithiocarbonates as sensitizers for silver halide emulsions
Assignee: EIDP Inc
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Filing: 1976-12-21
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Granted: 1978-01-10
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Expires: 1996-12-21
Abstract
Abstract Photographic colloid-silver halide emulsions are chemically sensitized by the addition prior to or during digestion of at least one trithiocarbonate compound of the general formula: ##STR1## wherein R is a tertiary alkyl radical having from 4 to 16 carbon atoms and R' may be the same as R or an aryl or an alphyl radical containing 1 to 3 aryl groups which may be substituted or unsubstituted.
Inventors
- 👤 John Howard Bigelow
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 18:55
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/005; G03C1/06; G03C1/08; G03C1/09
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
71 words
A photographic element comprising a support bearing at least one layer of a photographic silver halide emulsion which is chemically sensitized by the addition thereto prior to or during digestion of at least one trithiocarbonate of the general formula: ##STR9##wherein R is a tertiary alkyl radical having from 4 to 16 carbon atoms, and wherein R' is R or an aryl or an alphyl radical containing 1 to 3 phenyl groups.
Claim 2
Dependent Claim
71 words
A photographic element comprising a support bearing at least one layer of a photographic silver halide emulsion which is chemically sensitized by the addition thereto prior to or during digestion of at least one trithiocarbonate of the general formula: ##STR9##wherein R is a tertiary alkyl radical having from 4 to 16 carbon atoms, and wherein R' is R or an aryl or an alphyl radical containing 1 to 3 phenyl groups.
Claim 3
Dependent Claim
13 words
The composition of claim 1 wherein the trithiocarbonate is tert.-butyl triphenyl methyl-trithiocarbonate ##STR10##
Claim 4
Dependent Claim
11 words
The composition of claim 1 wherein the trithiocarbonate is di-tert.-butyl trithiocarbonate
Claim 5
Dependent Claim
14 words
The composition of claim 1 wherein the trithiocarbonate is 1,1-dimethyl propyl triphenyl methyl trithiocarbonate
Claim 6
Dependent Claim
13 words
The composition of claim 1 wherein the trithiocarbonate is tert.-butyl diphenyl methyl trithiocarbonate.
Claim 7
Dependent Claim
14 words
The composition of claim 1 wherein the trithiocarbonate is tert.-butyl phenol methyl trithiocarbonate ##STR11##
Claim 8
Dependent Claim
12 words
The composition of claim 1 wherein the trithiocarbonate is tert.-butyl phenyl trithiocarbonate
References Cited (Backward Citations)
US1678832A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-01-09 | 1981-07-11 | 1982-01-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-01-09 | 1985-07-11 | 1986-01-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-01-09 | 1989-07-11 | 1990-01-10 | $7700.00 | Window Closed / Lapsed |