US4791053A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Silver halide photographic material
Assignee: Fujifilm Holdings Corp
•
Filing: 1986-12-03
•
Granted: 1988-12-13
•
Expires: 2006-12-03
Abstract
Abstract A silver halide photographic material comprising a support having thereon at least one emulsion layer which contains a silver chlorobromide or silver chloride each having an iodide content of 3 mol % or less. The monodispersed emulsion is prepared in a process comprising the steps of, in sequence, forming silver halide grains which have a grain size distribution represented by a variation coefficient of 0.2 or less, causing halogen replacement in silver halide grains by addition of a water-soluble bromide in a proportion of from 0.6 to 20 mol % with respect to the total silver halide in the presence of at least one sensitizing dye selected from among simple cyanine dyes, carbocyanine dyes, and dicarbocyanine dyes at individual surfaces of the silver halide grains, and then subjecting the resulting silver halide grains to chemical sensitization, thereby achieving enhanced sensitivity and improved pressure characteristics.
Inventors
- 👤 Tadashi Ogawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 15:26
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/005; G03C1/015; G03C1/06; G03C1/08; G03C1/10; G03C1/12; G03C1/035; G03C2001/03523; G03C2001/03558; G03C2001/0357
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
132 words
A silver halide photographic material comprising a support having thereon at least one emulsion layer which contains a silver chlorobromide or silver bromide each having an iodide content of 3 mol% or less, which is prepared in a process comprising the steps of, in sequence, forming silver halide grains which have a grain size distribution represented by a variation coefficient of 0.2 or less, causing halogen replacement in silver halide grains by addition of a water-soluble bromide in a proportion of from 0.6 to 20 mol% with respect to the total silver halide in the presence of at least one sensitizing dye selected from among simple cyanine dyes, carbocyanine dyes, and dicarboncyanine dyes at individual surfaces of the silver halide grains, and then subjecting the resulting silver halide grains to chemical sensitization.
Claim 2
Dependent Claim
132 words
A silver halide photographic material comprising a support having thereon at least one emulsion layer which contains a silver chlorobromide or silver bromide each having an iodide content of 3 mol% or less, which is prepared in a process comprising the steps of, in sequence, forming silver halide grains which have a grain size distribution represented by a variation coefficient of 0.2 or less, causing halogen replacement in silver halide grains by addition of a water-soluble bromide in a proportion of from 0.6 to 20 mol% with respect to the total silver halide in the presence of at least one sensitizing dye selected from among simple cyanine dyes, carbocyanine dyes, and dicarboncyanine dyes at individual surfaces of the silver halide grains, and then subjecting the resulting silver halide grains to chemical sensitization.
Claim 3
Dependent Claim
31 words
A silver halide photographic material as in claim 1, wherein the water-soluble bromide is added in a proportion of from 1 to 15 mol% with respect to the total silver halide.
Claim 4
Dependent Claim
144 words
A silver halide photographic material as in claim 1, wherein said sensitizing dye is a cyanine dye represented by formula (I) ##STR8## wherein L represents a methine group or a substituted methine group; R 1 and R 2 each represents an alkyl group or a substituted alkyl group; Z 1 and Z 2 each represents atoms forming a nitrogen-containing 5- or 6-membered heterocyclic nucleus; X represents an anion; n represents 1, 3, or 5; n 1 and n 2 each represents 0 to 1, provided that n 1 and n 2 are 0 when n=5, and that when n=3, either n 1 or n 2 is 0; m represents 0 or 1, provided that m is 0 when (I) forms an internal salt; or, when n represents 5, the two L groups combine together to form a substituted or unsubstituted 5- or 6-membered ring.
Claim 5
Dependent Claim
144 words
A silver halide photographic material as in claim 2, wherein said sensitizing dye is a cyanine dye represented by formula (I) ##STR9## wherein L represents a methine group or a substituted methine group; R 1 and R 2 each represents an alkyl group or a substituted alkyl group; Z 1 and Z 2 each represents atoms forming a nitrogen-containing 5- or 6-membered heterocyclic nucleus; X represents an anion; n represents 1, 3 or 5; n 1 and n 2 each represents 0 to 1, provided that n 1 and n 2 are 0 when n=5, and that when n=3, either n 1 or n 2 is 0; m represents 0 or 1, provided that m is 0 when (I) forms an internal salt; or, when n represents 5, the two L groups combine together to form a substituted or unsubstituted 5- or 6-membered ring.
Claim 6
Dependent Claim
21 words
A silver halide photographic material as in claim 1, wherein said water-soluble bromide is potassium bromide, sodium bromide or ammonium bromide.
Claim 7
Dependent Claim
21 words
A silver halide photographic material as in claim 1, wherein said sensitizing dye contains a benzoxazole nucleus or a benzothiazole nucleus.
Claim 8
Dependent Claim
30 words
A silver halide photographic material as in claim 1, wherein a ratio of said sensitizing dye to the total silver halides ranges from 1×10 -5 to 4×10 -3 by mol.
Claim 9
Dependent Claim
30 words
A silver halide photographic material as in claim 1, wherein a ratio of said sensitizing dye to the total silver halides ranges from 3×10 -5 to 2×10 -3 by mol.
Claim 10
Dependent Claim
36 words
A silver halide photographic material as in claim 1, wherein the silver halide grains prior to halogen conversion have a chloride content of 4 to 100 mol% and an iodide content of 3 mol% or less.
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) | 1991-12-13 | 1992-06-13 | 1992-12-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-12-13 | 1996-06-13 | 1996-12-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-12-13 | 2000-06-13 | 2000-12-13 | $7700.00 | Window Closed / Lapsed |