US4116697A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sulfur-substituted isothioureas in silver halide emulsions
Assignee: EIDP Inc
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Filing: 1978-01-20
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Granted: 1978-09-26
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Expires: 1998-01-20
Abstract
Abstract Photographic silver halide emulsions which have their sensitivity increased by the addition of sulfur-substituted isothioureas of the formula; ##STR1## where R, R 2 , and R 3 are organic radicals and R 1 is an organic radical or H.
Inventors
- 👤 John Howard Bigelow
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 22:07
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/005; G03C1/06; G03C1/08; G03C1/09
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
94 words
A light-sensitive silver halide photographic element comprising a support coated with a silver halide emulsion containing a sulfur-substituted isothiourea of the formula: ##STR20## or its hydrohalide salt having the formula ##STR21## where R, R 1 , R 2 , and R 3 are each selected from the group consisting of alkyl, aryl, hetero, substituted alkyl, and substituted aryl, and wherein R 1 may optionally represent H, and X is iodine or chlorine, said isothiourea or its salt being employed in an amount sufficient to increase the Dmax and contrast of the silver halide emulsion.
Claim 2
Dependent Claim
94 words
A light-sensitive silver halide photographic element comprising a support coated with a silver halide emulsion containing a sulfur-substituted isothiourea of the formula: ##STR20## or its hydrohalide salt having the formula ##STR21## where R, R 1 , R 2 , and R 3 are each selected from the group consisting of alkyl, aryl, hetero, substituted alkyl, and substituted aryl, and wherein R 1 may optionally represent H, and X is iodine or chlorine, said isothiourea or its salt being employed in an amount sufficient to increase the Dmax and contrast of the silver halide emulsion.
Claim 3
Dependent Claim
11 words
The photographic element of claim 1 wherein said isothiourea is N-n-butyl-N'-dimethylamino-S-methylisothiourea.
Claim 4
Dependent Claim
11 words
The photographic element of claim 1 wherein said isothiourea is N-n-butyl-N'-dimethylamino-S-N-methylcarbamoylisothiourea.
Claim 5
Dependent Claim
11 words
The photographic element of claim 1 wherein said isothiourea is N-phenyl-N'-dimethylamino-S-N-methylcarbamoylisothiourea.
Claim 6
Dependent Claim
12 words
The photographic element of claim 1 wherein said isothiourea is N-phenyl-N'-dimethylamino-S-methylisothiourea hydroiodide.
Claim 7
Dependent Claim
11 words
The photographic element of claim 1 wherein said isothiourea is N-phenyl-N'-diphenylamino-S-methylisothiourea.
Claim 8
Dependent Claim
11 words
The photographic element of claim 1 wherein said isothiourea is N-phenyl-N'-dimethylamino-S-methylisothiourea.
Claim 9
Dependent Claim
12 words
The photographic element of claim 1 wherein said isothiourea is N-phenyl-N'-dimethyl-S-methylisothiourea hydroiodide.
Claim 10
Dependent Claim
140 words
A light-sensitive silver halide photographic element comprising a support coated with a silver halide emulsion containing a sulfur-substituted isothiourea of the formula: ##STR22## or its hydrohalide salt having the formula ##STR23## wherein R is selected from the group consisting of alkyl, aryl, and substituted aryl; R 1 , R 2 , and R 3 are each selected from the group consisting of alkyl, aryl, hetero, substituted alkyl, and substitued aryl, and wherein R 1 may optionally represent H, and wherein R 2 and R 3 may form a ring of two or more > CH 2 groups in which one or more of the H atoms may be substituted by R, and wherein X is iodine or chlorine, said isothiourea or its salt being employed in an amount sufficient to increase the Dmax and contrast of the silver halide emulsion.
Claim 11
Dependent Claim
140 words
A light-sensitive silver halide photographic element comprising a support coated with a silver halide emulsion containing a sulfur-substituted isothiourea of the formula: ##STR22## or its hydrohalide salt having the formula ##STR23## wherein R is selected from the group consisting of alkyl, aryl, and substituted aryl; R 1 , R 2 , and R 3 are each selected from the group consisting of alkyl, aryl, hetero, substituted alkyl, and substitued aryl, and wherein R 1 may optionally represent H, and wherein R 2 and R 3 may form a ring of two or more > CH 2 groups in which one or more of the H atoms may be substituted by R, and wherein X is iodine or chlorine, said isothiourea or its salt being employed in an amount sufficient to increase the Dmax and contrast of the silver halide emulsion.
Claim 12
Dependent Claim
12 words
The photographic element of claim 9 wherein said isothiourea is 1-phenylethylene-S-methyl-isothiourea hydroiodide.
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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) | 1981-09-25 | 1982-03-27 | 1982-09-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-09-25 | 1986-03-27 | 1986-09-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-09-25 | 1990-03-27 | 1990-09-26 | $7700.00 | Window Closed / Lapsed |