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US4452883A Expired / Lapsed US ⏱️ 0.0 years remaining

Barrier resin for photothermographic color separation

Assignee: Eastman Kodak Co
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Filing: 1983-05-17
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Granted: 1984-06-05
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Expires: 2003-05-17
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Abstract

Abstract A photothermographic color construction is disclosed, the construction having at least two color-forming layers comprising: a. a first, spectrally-sensitized, color-forming layer coated out of a solvent system selected from lower alkyl alcohols (up to 4 carbon atoms) ketones (up to 6 carbon atoms), aromatic hydrocarbons (up to 10 carbon atoms), or mixtures thereof, b. an upper, second, different, spectrally-sensitized color-forming layer coated out of a toluene or acetone solvent system, and c. a barrier layer comprising a polymer and a color developer coated between said first and second color-forming layers, said polymer being impervious to toluene or acetone, said polymer being an admixture of a first polymer, polyvinylpyrrolidone (PVP), and a second polymer which is (i) a neutralized and (ii) a hydrolyzed or lower alkyl-esterfied form of a poly(methyl vinyl ether/maleic anhydride) copolymer, in the range of 30 weight percent PVP/70 weight percent neutralized second polymer to 75 weight percent PVP/25 weight percent neutralized second polymer (the weight percentages being of the solventless admixture) said barrier layer is impervious to the solvent system of an overlaying color-forming layer; and further wherein each color-forming layer is sensitized to a portion of the spectrum at least 60 nm different from the other color-forming layer, and each color-forming layer contains a leuco dye (colorless) which when oxidized forms a dye (colored) having a maximum absorbance at least 60 nm different from that of the dye (colored) formed in the other color-forming layer.

Inventors

  • 👤 Robert A. Frenchik
  • 👤 Kristen A. Hoff

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-31 09:13
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/494; G03C1/498; G03C1/49872

Claims Analysis

Total Claims: 18
Claim 1
Independent Claim 220 words
A photothermographic color construction having at least two different mono-color-forming layers comprising: a. a first, spectrally-sensitized, color-forming layer coated out of a solvent system selected from lower alkyl alcohols, aliphatic ketones, aromatic hydrocarbons, or mixtures thereof, b. an upper, second, different, spectrally-sensitized, color-forming layer coated out of a toluene or acetone solvent system, and c. a barrier layer comprising a polymer and a color developer coated between said first and second color-forming layers, said polymer being impervious to toluene or acetone, said polymer being an admixture of a first polymer, polyvinylpyrrolidone, and a second polymer which is (i) a neutralized and (ii) a hydrolyzed or lower alkyl-esterified form of a poly(methyl vinyl ether/maleic anhydride) copolymer, in the range of 30 weight percent polyvinylpyrrolidone to 70 weight percent neutralized second polymer to 75 weight percent polyvinylpyrrolidone to 31 weight percent neutralized second polymer; and wherein each color-forming layer is sensitized to a portion of the spectrum at least 60 nm different from the other color-forming layer, and each color-forming layer contains a silver source, silver halide, and a leuco dye which when oxidized forms a dye having a maximum absorbance at least 60 nm different from that of the dye formed in the other color-forming layer, and the barrier polymer is impervious to the solvent system of any adjacent color-forming layer.
Claim 2
Dependent Claim 220 words
A photothermographic color construction having at least two different mono-color-forming layers comprising: a. a first, spectrally-sensitized, color-forming layer coated out of a solvent system selected from lower alkyl alcohols, aliphatic ketones, aromatic hydrocarbons, or mixtures thereof, b. an upper, second, different, spectrally-sensitized, color-forming layer coated out of a toluene or acetone solvent system, and c. a barrier layer comprising a polymer and a color developer coated between said first and second color-forming layers, said polymer being impervious to toluene or acetone, said polymer being an admixture of a first polymer, polyvinylpyrrolidone, and a second polymer which is (i) a neutralized and (ii) a hydrolyzed or lower alkyl-esterified form of a poly(methyl vinyl ether/maleic anhydride) copolymer, in the range of 30 weight percent polyvinylpyrrolidone to 70 weight percent neutralized second polymer to 75 weight percent polyvinylpyrrolidone to 31 weight percent neutralized second polymer; and wherein each color-forming layer is sensitized to a portion of the spectrum at least 60 nm different from the other color-forming layer, and each color-forming layer contains a silver source, silver halide, and a leuco dye which when oxidized forms a dye having a maximum absorbance at least 60 nm different from that of the dye formed in the other color-forming layer, and the barrier polymer is impervious to the solvent system of any adjacent color-forming layer.
Claim 3
Dependent Claim 35 words
The construction according to claim 1 wherein said range of polyvinylpyrrolidone to neutralized second polymer, is 55 weight percent polyvinylpyrrolidone/45 weight percent neutralized second polymer to 69 weight percent polyvinylpyrrolidone/31 weight percent neutralized second polymer.
Claim 4
Dependent Claim 48 words
The construction according to claim 1 wherein said second polymer is selected from the group consisting of poly(methyl vinyl ether/maleic anhydride), hydrolyzed poly(methyl vinyl ether/maleic acid), monoethyl ester of poly(methyl vinyl ether/maleic acid), monoisopropyl ester of poly(methyl vinyl ether/maleic acid), and monobutyl ester of poly(methyl vinyl ether/maleic acid).
Claim 5
Dependent Claim 19 words
The construction according to claim 3 wherein said second polymer is the monoethyl ester of poly(methyl vinyl ether/maleic acid).
Claim 6
Dependent Claim 17 words
The construction according to claim 1 wherein said color-forming systems and said barrier polymer are coated simultaneously.
Claim 7
Dependent Claim 27 words
The construction according to claim 1 wherein said barrier polymer is coated out of an organic solvent which comprises at least 50 weight percent lower alkyl alcohol.
Claim 8
Dependent Claim 13 words
The construction according to claim 1 wherein said lower alkyl alcohol is methanol.
Claim 9
Dependent Claim 29 words
The construction according to claim 1 further comprising a third, different, spectrally sensitized, color-forming layer coated out of a lower alkyl alcohol solvent system overlying said second color-forming layer.
Claim 10
Dependent Claim 23 words
The construction according to claim 8 further comprising a second barrier layer impervious to alcohol between said second and said third color-forming layer.
Claim 11
Dependent Claim 36 words
The construction according to claim 1 further comprising a second barrier layer and a third color-forming layer underlying said first color-forming layer, said second barrier layer being impervious to the solvent of said first color-forming layer.
Claim 12
Dependent Claim 19 words
The construction of claim 1 wherein the binder for at least one of said photothermographic layers comprises polyvinyl butyral.
Claim 13
Dependent Claim 19 words
The construction of claim 8 wherein the binder for at least one of said photothermographic layers comprises polyvinyl butyral.
Claim 14
Dependent Claim 19 words
The article of claim 10 wherein the binder for at least one of said photothermographic layers comprises polyvinyl butyral.
Claim 15
Dependent Claim 17 words
The article of claim 8 wherein at least one of said photothermographic layers further comprises a toner.
Claim 16
Dependent Claim 17 words
The article of claim 10 wherein at least one of said photothermographic layers further comprises a toner.
Claim 17
Dependent Claim 30 words
The article of claim 8 wherein said toner comprises phthalizine in combination with an acid selected from the group consisting of (a) phthalic acid and (b) derivatives of phthalic acid.
Claim 18
Dependent Claim 30 words
The article of claim 10 wherein said toner comprises phthalizine in combination with an acid selected from the group consisting of (a) phthalic acid and (b) derivatives of phthalic acid.

References Cited (Backward Citations)

US2761791A Cited
GB837095A Cited
US3531286A Cited
US4021240A Cited
US4260677A Cited
US4283477A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1987-06-05 1987-12-05 1988-06-05 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1991-06-05 1991-12-05 1992-06-05 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1995-06-05 1995-12-05 1996-06-05 $7700.00 Window Closed / Lapsed

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