Patent EP0374837B1 successfully refreshed from Google Patents.
EP0374837B1
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Stabilization of precipitated dispersions of hydrophobic couplers
Assignee: Eastman Kodak Co
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Filing: 1989-12-19
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Granted: 1995-03-01
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Expires: 2009-12-19
Abstract
No abstract record available.
Inventors
- 👤 Krishnan C/O Eastman Kodak Company Chari
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-05 07:01
CPC Classifications
G; G03; G03C; G03C7/00; G03C7/30; G03C7/32; G03C7/3212; G03C7/388; G03C7/3882
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
100 words
A method of forming stable dispersions of hydrophobic couplers having short hydrocarbon chain ballast groups of up to 15 carbon atoms characterized by forming a water solution by dissolving in water a nonionic polymer and an anionic surfactant, said surfactant having no oxyethylene groups, a hydrophilic head group comprising sulfate or sulfonate and a hydrophobic tail group comprising between 8 and 20 carbon atoms, forming a solvent solution by dissolving a coupler in a basic solvent solution, combining said solvent solution and said water solution, and adding acid to form a neutral combined solution containing a dispersion of coupler particles.
Claim 2
Dependent Claim
35 words
The method of Claim 1 wherein said coupler is characterized by the structure wherein COUP is a coupler moiety, is a ballast group, and R is a hydrocarbon chain of 2 to 15 carbon atoms.
Claim 3
Dependent Claim
16 words
The method of Claim 1 wherein said coupler is selected from the group consisting of and
Claim 4
Dependent Claim
34 words
The method of Claim 1 wherein said surfactant is selected from the group consisting of sodium bis(2-ethyl hexyl) sulfosuccinate, sodium tetradecyl sulfate, and sodium di(heptyl) sulfosuccinate, sodium dodecyl sulfate, and sodium dodecyl benzene sulfonate.
Claim 5
Dependent Claim
29 words
The method of Claim 4 wherein said nonionic polymer is selected from at least one member of the group consisting of polyvinylpyrrolidone, polyethyleneoxide, polyvinyl alcohol, polypropylene oxide, and methylcellulose.
Claim 6
Dependent Claim
67 words
A dispersion comprising water, particles of a photographic coupler having a ballast group comprising a straight chain hydrocarbon of up to 15 carbon atoms characterized in that said dispersion further comprises a surfactant comprising a head group of sulfate or sulfonate, a hydrophobic group of 8 to 20 carbon atoms and having no oxyethylene groups, and a nonionic water soluble polymer that is attracted to said surfactant.
Claim 7
Dependent Claim
18 words
The dispersion of Claim 6 wherein said coupler comprises a member selected from the group consisting of: and
Claim 8
Dependent Claim
24 words
The dispersion of Claim 7 wherein said sulfate or sulfonate may be represented as an SO₃M or OSO₃M moiety where M represents a cation.
Claim 9
Dependent Claim
20 words
The dispersion of Claim 8 wherein the median particle size of said coupler particles is between 8 and 300 nm.
References Cited (Backward Citations)
No citation records indexed.
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