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US4731291A Expired / Lapsed US ⏱️ 0.0 years remaining

Water-resistant photographic paper support

Assignee: Felex Schoeller Jr and GmbH and Co KG
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Filing: 1986-11-21
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Granted: 1988-03-15
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Expires: 2006-11-21
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Abstract

Abstract A photographic paper support material for photographic purposes is disclosed with a polyolefin coating on both sides, wherein the base paper is internally sized by using a hydrophobizing sizing agent, and is surface sized with an aqueous coating mixture. The aqueous coating mixture contains a carboxyl-modified polyvinyl alcohol and optionally includes compounds with polyvalent cations. The paper support material is preferably used with such photographic layers as require wet development and wet fixing of the photographic image with photographic processing solutions.

Inventors

  • 👤 Alois-Bernhard Kerkhoff
  • 👤 Dietmar Bunke

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 20:47
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/76; G03C1/775; G03C1/79; Y; Y10; Y10T; Y10T428/00; Y10T428/27; Y10T428/273; Y10T428/277; Y10T428/31504; Y10T428/31855; Y10T428/3188; Y10T428/31895; Y10T428/31899; Y10T428/31902; Y10T428/31971; Y10T428/31993; Y10T428/31996

Claims Analysis

Total Claims: 21
Claim 1
Independent Claim 69 words
A water-resistant photographic paper support, comprising a base paper internally sized with at least one hydrophobizing sizing agent, surface sized with an aqueous coating mixture, and coated with a polyolefin on both sides, said aqueous coating mixture including a copolymer of an ethylenically unsaturated monobasic carboxylic acid and vinyl alcohol with a saponification grade of at least 96% and having a carboxyl group content of about 1.5-7 mol. %.
Claim 2
Dependent Claim 69 words
A water-resistant photographic paper support, comprising a base paper internally sized with at least one hydrophobizing sizing agent, surface sized with an aqueous coating mixture, and coated with a polyolefin on both sides, said aqueous coating mixture including a copolymer of an ethylenically unsaturated monobasic carboxylic acid and vinyl alcohol with a saponification grade of at least 96% and having a carboxyl group content of about 1.5-7 mol. %.
Claim 3
Dependent Claim 18 words
The water-resistant photographic paper support of claim 1, wherein said carboxyl group content is about 2.5-3.5 mol. %.
Claim 4
Dependent Claim 17 words
The water-resistant photographic paper support of claim 1, wherein said monobasic carboxylic acid is crotonicor iso-crotonic acid.
Claim 5
Dependent Claim 17 words
The water-resistant photographic paper support of claim 1, wherein said monobasic carboxylic acid is acrylicor or methacrylic-acid.
Claim 6
Dependent Claim 29 words
The water-resistant photographic paper support of claim 1, wherein said carboxylated polyvinyl alcohol has a viscosity between 20 and 50 mPa's at room temperature and in 4% aqueous solution.
Claim 7
Dependent Claim 28 words
The water-resistant photographic paper support of claim 1, wherein said carboxylated polyvinyl alcohol is applied to the base paper in an amount of about 0.5-10 g/m 2 .
Claim 8
Dependent Claim 17 words
The water-resistant photographic paper support of claim 6, wherein said amount is about 1-4.5 g/m 2 .
Claim 9
Dependent Claim 38 words
The water-resistant photographic paper support of claim 1, wherein said aqueous coating mixture also includes a compound with polyvalent cations, and said carboxylated polyvinyl alcohol is a copolymer of an ethylenically unsaturated monobasic carboxylic acid and vinyl alcohol.
Claim 10
Dependent Claim 22 words
The water-resistant photographic paper support of claim 8, wherein said compound with polyvalent cations is a salt of the alkaline earth metals.
Claim 11
Dependent Claim 17 words
The water-resistant photographic paper support of claim 9, wherein said salt is calcium chloride or magnesium chloride.
Claim 12
Dependent Claim 18 words
The water-resistant photographic paper support of claim 8, wherein said compound with polyvalent cations is an aluminum salt.
Claim 13
Dependent Claim 18 words
The water-resistant photographic paper support of claim 11, wherein said aluminum salt is aluminum sulfate or aluminum chloride.
Claim 14
Dependent Claim 21 words
The water-resistant photographic paper support of claim 8, wherein said compound with polyvalent cations is a compound of the transition metals.
Claim 15
Dependent Claim 19 words
A water-resistant photographic paper support of claim 13, wherein said compound of the transition metals is a zirconium compound.
Claim 16
Dependent Claim 19 words
The water-resistant photographic paper support of claim 14, wherein said zirconium compound is zirconium ammonium carbonate or zirconium orthosulfate.
Claim 17
Dependent Claim 19 words
The water-resistant photographic paper support of claim 13, wherein said compound of the transition metals is a chromium compound.
Claim 18
Dependent Claim 20 words
The water-resistant photographic paper support of claim 16, wherein said chromium compound is a chromium complex of the Werner type.
Claim 19
Dependent Claim 28 words
The water-resistant photographic paper support of claim 8, wherein said compound with polyvalent cations has a weight ratio to the carboxylated polyvinyl alcohol of about 1/10 to 5/1.
Claim 20
Dependent Claim 21 words
The water-resistant photographic paper support of claim 1, wherein said base paper also includes at least one compound with polyvalent cations.
Claim 21
Dependent Claim 30 words
The water-resistant photographic paper support of claim 19, wherein said carboxylated polyvinyl alcohol is treated with said polyvalent cations after the polyvinyl alcohol has been applied to said base paper.

References Cited (Backward Citations)

JPS4994275A Cited
US4327174A Cited
GB2066732A Cited
GB2109704A Cited
US4478910A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1991-03-15 1991-09-14 1992-03-15 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1995-03-15 1995-09-14 1996-03-15 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1999-03-15 1999-09-14 2000-03-15 $7700.00 Window Closed / Lapsed

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