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US4168167A Expired / Lapsed US ⏱️ 0.0 years remaining

Presensitized printing plates for lithographic printing

Assignee: Fujifilm Holdings Corp
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Filing: 1977-08-04
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Granted: 1979-09-18
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Expires: 1997-08-04
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Abstract

Abstract Presensitized printing plates for lithographic printing which comprise an aluminum support having an anodically oxidized aluminum oxide film thereon and a light-sensitive layer containing internal latent image type silver halide grains which are not fogged on the anodically oxidized aluminum oxide film on the support.

Inventors

  • 👤 Haruo Takenaka
  • 👤 Keisuke Shiba
  • 👤 Kikuo Kubotera
  • 👤 Akira Kashiwabara

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 09:27
CPC Classifications
B; B41; B41N; B41N3/00; B41N3/03; B41N3/034; G; G03; G03F; G03F7/00; G03F7/004; G03F7/06

Claims Analysis

Total Claims: 24
Claim 1
Independent Claim 89 words
A method of producing a lithographic printing plate which comprises (a) image-wise exposing to light a presensitized lithographic printing plate comprising an aluminum support having an anodically oxidized aluminum oxide film thereon and a light-sensitive layer of an internal latent image silver halide emulsion containing both a fogging agent or a precursor thereof and a tanning developing agent, (b) tanning developing said imagewise exposed printing plate with an aqueous alkaline solution and then (c) washing off said developed printing plate to remove the untanned area of said light-sensitive layer.
Claim 2
Independent Claim 89 words
A method of producing a lithographic printing plate which comprises (a) image-wise exposing to light a presensitized lithographic printing plate comprising an aluminum support having an anodically oxidized aluminum oxide film thereon and a light-sensitive layer of an internal latent image silver halide emulsion containing both a fogging agent or a precursor thereof and a tanning developing agent, (b) tanning developing said imagewise exposed printing plate with an aqueous alkaline solution and then (c) washing off said developed printing plate to remove the untanned area of said light-sensitive layer.
Claim 3
Dependent Claim 20 words
The method of claim 1, wherein said aluminum oxide film has a thickness of about 0.1 to about 50 microns.
Claim 4
Dependent Claim 26 words
The method of claim 1, wherein the silver halide in said silver halide emulsion has a particle size from about 0.1 micron to about 5 microns.
Claim 5
Dependent Claim 24 words
The method of claim 1, wherein the silver halide of said silver halide emulsion is silver chloride, silver bromide, silver iodide, or silver iodobromide.
Claim 6
Dependent Claim 41 words
The method of claim 1, wherein said fogging agent is 2-methyl-3-[3-(p-sulfophenylhydrazono)propyl]benzothiazolium bromide, 2-methyl-3-(β-hydroxyethyl)benzothiazolium bromide, p-methane-sulfonamidoethylphenylhydrazine and 1,2-dihydro-3-methyl-4-phenylpyrido (2,1-b)benzothiazolium bromide, wherein said fogging agent precursor is 3-(2-acetylethyl)-2-benzylbenzo-selenazolium bromide and wherein developing agent is a hydroquinone, a catechol, a resorcinol or a pyrogallol.
Claim 7
Dependent Claim 19 words
The method of claim 1, wherein said aqueous alkaline solution has a pH of about 9.5 to about 13.0.
Claim 8
Dependent Claim 17 words
The method of claim 1, wherein said aqueous alkaline solution has a pH of 10.5 to 12.3.
Claim 9
Dependent Claim 26 words
The method of claim 7, wherein said aqueous solution is an aqueous solution of sodium carbonate, sodium phosphate, sodium hydroxide, potassium hydroxide or a mixture thereof.
Claim 10
Dependent Claim 29 words
The method of claim 1, wherein said fogging agent or said precursor is incorporated in an amount from about 0.01 to 10 millimol per mol of the silver halide.
Claim 11
Dependent Claim 29 words
The method of claim 5, wherein said fogging agent or said precursor is incorporated in an amount from about 0.01 to 10 millimol per mol of the silver halide.
Claim 12
Dependent Claim 21 words
The method of claim 7, wherein said tanning development is conducted at a temperature of about 27° to about 40° C.
Claim 13
Dependent Claim 24 words
The method of claim 1, wherein washing off is carried out with a warm water at a temperature of higher than about 35° C.
Claim 14
Dependent Claim 18 words
The method of claim 1, further including heating said washed off plate to strengthen said tanned light-sensitive layer.
Claim 15
Dependent Claim 21 words
The method of claim 13, wherein said heating is conducted under the condition of about 200° C. for about 1 minute.
Claim 16
Dependent Claim 21 words
The method of claim 1, further including irradiating said washed off plate with electro-magnetic radiation to strengthen said tanned light-sensitive layer.
Claim 17
Dependent Claim 15 words
The method of claim 15, wherein said electro-magnetic radiation is ultraviolet light or infrared light.
Claim 18
Dependent Claim 22 words
The method of claim 1, further including subjecting said washed off plate to a hardening treatment to strengthen said tanned light-sensitive layer.
Claim 19
Dependent Claim 28 words
The method of claim 1, wherein said hardening treatment is conducted by immersion in a solution of chrome alum or an epoxy compound followed by drying with heat.
Claim 20
Dependent Claim 24 words
The method of claim 1, wherein said presensitized lithographic printing plate has a subbing layer between said aluminum oxide film and said light-sensitive layer.
Claim 21
Dependent Claim 23 words
The method of claim 19, wherein said subbing layer is a layer of gelatin, a gelatin derivative, polyvinyl alcohol, polyvinyl pyrrolidone or polyvinylimidazole.
Claim 22
Dependent Claim 18 words
The method of claim 1, wherein said presensitized printing plate has a protective layer on said light-sensitive layer.
Claim 23
Dependent Claim 44 words
The method of claim 21, wherein said protective layer is a layer comprising a polymerization product prepared from 1 mol of 4,4'-methylenediphenylisocyanate and 2 mols of hydroxyethyl acrylate and a polymer having the repeated unit ##STR2## and having a molecular weight of about 10,000.
Claim 24
Dependent Claim 34 words
The method of claim 1, wherein said aqueous alkaline solution has the following composition: ______________________________________ Sodium Carbonate (anhydrous) 112.5 g Potassium Bromide 1.5 g Sodium Polymethaphosphate 1 g Water to make 1,000 ml ______________________________________

References Cited (Backward Citations)

US3295969A Cited
US3402045A Cited
US3551150A Cited
US3600166A Cited
US3615615A Cited
US3719494A Cited
US3734738A Cited
US3761276A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1982-09-17 1983-03-19 1983-09-18 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1986-09-17 1987-03-19 1987-09-18 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1990-09-17 1991-03-19 1991-09-18 $7700.00 Window Closed / Lapsed

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