EP0358187A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Tabular grain photographic elements exhibiting reduced pressure sensitivity (II)
Assignee: Eastman Kodak Co
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Filing: 1989-09-06
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Granted: —
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Expires: 2009-09-06
Abstract
Abstract A photographic element is disclosed comprised of a support and, coated on the support, at least one radiation-sensitive silver halide emulsion comprised of tabular silver halide grains and a dispersing medium. The emulsion includes as a vehicle methacrylate polymer latex capable of reducing pressure sensitivity having a glass transition temperature of less than 50°C.
Inventors
- 👤 Glen Marshall C/O Eastman Kodak Company Dappen
- 👤 Wayne Arthur C/O Eastman Kodak Company Bowman
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 17:53
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/005; G03C1/04; G03C1/053; G03C1/0051
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
125 words
A photographic element comprised of a support and, coated on the support, at least one radiation-sensitive silver halide emulsion comprised of silver halide grains dispersed in a vehicle, at least 50 percent of the total projected area of the silver halide grains being comprised of tabular grains satisfying the relationship: ECD/t²>25 where ECD is the average equivalent circular diameter in µm of the tabular grains and t is the average thickness in µm of the tabular grains, and the vehicle being comprised of hydrophilic colloid forming a continuous phase and a latex, characterized in that the vehicle contains in an amount sufficient to reduce pressure sensitivity a latex consisting essentially of a methacrylate polymer selected to have a glass transition temperature of less than 50°C.
Claim 2
Dependent Claim
125 words
A photographic element comprised of a support and, coated on the support, at least one radiation-sensitive silver halide emulsion comprised of silver halide grains dispersed in a vehicle, at least 50 percent of the total projected area of the silver halide grains being comprised of tabular grains satisfying the relationship: ECD/t²>25 where ECD is the average equivalent circular diameter in µm of the tabular grains and t is the average thickness in µm of the tabular grains, and the vehicle being comprised of hydrophilic colloid forming a continuous phase and a latex, characterized in that the vehicle contains in an amount sufficient to reduce pressure sensitivity a latex consisting essentially of a methacrylate polymer selected to have a glass transition temperature of less than 50°C.
Claim 3
Dependent Claim
25 words
A photographic element according to claim 1 further characterized in that the methacrylate polymer selected to have a glass transition temperature of less than 35°C.
Claim 4
Dependent Claim
25 words
A photographic element according to claim 2 further characterized in that the methacrylate polymer selected to have a glass transition temperature of less than -20°C.
Claim 5
Dependent Claim
34 words
A photographic element according to any one of claims 1 to 3 inclusive further characterized in that the weight ratio of latex to hydrophilic colloid is in the range of from 4:1 to 1:4.
Claim 6
Dependent Claim
28 words
A photographic element according to claim 4 further characterized in that the weight ratio of latex to hyrophilic colloid is in the range of from 3:1 to 1:3.
Claim 7
Dependent Claim
45 words
A photographic element according to any one of claims 1 to 5 inclusive claim 1 further characterized in that at least 50 percent by weight of the repeating units forming the methacrylate polymer are derived from methacrylate ester monomers containing up to 22 carbon atoms.
Claim 8
Dependent Claim
37 words
A photographic element according to claim 6 further characterized in that said methacrylate ester monomers are selected to satisfy the formula: H₂C=CH- -O-R where R is an ester forming moiety containing from 3 to 12 carbon atoms.
Claim 9
Dependent Claim
24 words
A photographic element according to claim 7 further characterized in that R is an ester forming moiety contains from 4 to 10 carbon atoms.
Claim 10
Dependent Claim
35 words
A photographic element according to any one of claims 1 to 8 inclusive further characterized in that 5 to 20 percent by weight of the methacrylate polymer is formed of repeating units providing hardening sites.
Claim 11
Dependent Claim
34 words
A photographic element according to claim 9 further characterized in that hardening sites are provided by moieties selected from the group consisting of active methylene, azirdine or oxirane, primary amine, and vinyl precursor moieties.
Claim 12
Dependent Claim
59 words
A photographic element according to any one of claims 1 to 10 inclusive further characterized in that 1 to 10 percent by weight of the methacrylate polymer is formed of repeating units containing polar pendant groups chosen from the class consisting of - -O-M and where M is hydrogen, alkali metal or ammonium and n is zero or 1.
Claim 13
Dependent Claim
29 words
A photographic element according to any one of claims 1 to 11 inclusive further characterized in that said tabular grains have an average aspect ratio of greater than 8:1.
References Cited (Backward Citations)
No citation records indexed.
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