EP0506077A1
Expired / Lapsed
EP
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Mid-green sensitizing dyes for photographic materials
Assignee: Eastman Kodak Co
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Filing: 1992-03-27
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Granted: —
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Expires: 2012-03-27
Abstract
Abstract Dyes of formula (I) below are described. The dyes are useful as mid-green sensitizing dyes for photographic materials. In the above formula, R1 and R3 are methyl or ethyl, at least one of R1 and R3 being methyl. R2 and R4 are substituted or unsubstituted C₁ to C₆ alkyl, provided that R2 and R4 are not both methyl. X1, X2, X3, and X4 are each independently methyl, methylthio, fluoro-substituted methyl or methylthio, or hydrogen, provided that at least one of X1 and X2 and at least one of X3 and X4 are not hydrogen. Y represents an ion as needed to balance the charge of the molecule. The dyes of formula (I) sensitize silver halide to light in the mid-green region of the spectrum.
Inventors
- 👤 Richard B. c/o EASTMAN KODAK COMPANY Anderson
- 👤 Robert E. c/o EASTMAN KODAK COMPANY Dickerson
- 👤 Steven G. c/o EASTMAN KODAK COMPANY Link
- 👤 Fred M. c/o EASTMAN KODAK COMPANY Macon
- 👤 Wayne W. II c/o EASTMAN KODAK COMPANY Weber
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-03 02:12
CPC Classifications
C; C09; C09B; C09B23/00; C09B23/02; C09B23/06; G; G03; G03C; G03C1/00; G03C1/005; G03C1/06; G03C1/08; G03C1/10; G03C1/12; G03C1/14; G03C1/18
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
99 words
A photographic sensitizing dye according to the following formula I: characterized in that R1 and R3 are methyl or ethyl, at least one of R1 and R3 being methyl; R2 and R4 are substituted or unsubstituted C₁ to C₆ alkyl, provided that R2 and R4 are not both methyl; X1, X2, X3, and X4 are each independently methyl, methylthio, fluoro-substituted methyl or methylthio, or hydrogen, provided that at least one of X1 and X2 and at least one of X3 and X4 are not hydrogen; and Y represents an ion as needed to balance the charge of the molecule.
Claim 2
Dependent Claim
60 words
A photographic sensitizing dye according to claim 1 further characterized in that the combination of substituents R1-R4 and X1-X4 are selected to fit the following equation (i): (i) 0.455Σσ i (R1-R4) + 0.144Σσ p (X1-X4) + 0.610 ≧ 0.68 where the small sigmas are electronic substituent constants, σ i being Taft's sigma(inductive) constant, and σ p being Hammett's sigma(para) constant.
Claim 3
Dependent Claim
113 words
A photographic element comprising a support having thereon a silver halide emulsion layer sensitized with a sensitizing dye according to the following formula I: characterized in that R1 and R3 are methyl or ethyl, at least one of R1 and R3 being methyl; R2 and R4 are substituted or unsubstituted C₁ to C₆ alkyl, provided that R2 and R4 are not both methyl; X1, X2, X3, and X4 are each independently methyl, methylthio, fluoro-substituted methyl or methylthio, or hydrogen, provided that at least one of X1 and X2 and at least one of X3 and X4 are not hydrogen; and Y represents an ion as needed to balance the charge of the molecule.
Claim 4
Dependent Claim
17 words
A photographic element according to claim 3 further characterized in that R1 and R3 are each methyl.
Claim 5
Dependent Claim
18 words
A photographic element according to claim 3 further characterized in that R1 is methyl and R3 is ethyl.
Claim 6
Dependent Claim
22 words
A photographic element according to claim 3 further characterized in that at least one of X1, X2, X3 and X4 is trifluoromethyl.
Claim 7
Dependent Claim
20 words
A photographic element according to claim 3 further characterized in that at least one of R2 and R4 is sulfoalkyl.
Claim 8
Dependent Claim
22 words
A photographic element according to claim 3 further characterized in that at least one of R2 and R4 is a fluoro-substituted alkyl.
Claim 9
Dependent Claim
20 words
A photographic element according to claim 8 further characterized in that at least one of R2 and R4 is trifluoroethyl.
Claim 10
Dependent Claim
59 words
A photographic element according to claim 3 further characterized in that the combination of substituents R1-R4 and X1-X4 are selected to fit the following equation (i): (i) 0.455Σσ i (R1-R4) + 0.144Σσ p (X1-X4) + 0.610 ≧ 0.68 where the small sigmas are electronic substituent constants, σ i being Taft's sigma(inductive) constant, and σ p being Hammett's sigma(para) constant.
References Cited (Backward Citations)
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