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US4963472A Expired / Lapsed US ⏱️ 0.0 years remaining

Developing method for printing plates for waterless offset printing with glycol diether containing developer

Assignee: Hoechst AG
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Filing: 1988-05-11
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Granted: 1990-10-16
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Expires: 2008-05-11
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Abstract

Abstract A developing method for printing plates employing waterless offset processes is disclosed. The plates comprise a support coated with a photosensitive layer based on a diazonium salt polycondensation product and a super-imposed ink-repellent, crosslinked silicone elastomer layer, whereby said developer is characterized in that it contains a predominant proportion of compounds of the general formula R--(O--CH 2 --CH 2 --) n --O--R, where R denotes C m H 2m+1 , n denotes an integer from 1 to 25 and m denotes an integer from 1 to 5. The present invention is particularly suitable for developing printing plates where the photosensitive layer comprises a diazonium salt polycondensation product comprising recurrent A--N 2 X and B units which are mutually linked by bridge members, especially methylene groups, which are derived from carbonyl compounds capable of condensation, A being the radical of an aromatic diazonium compound capable of condensation with formaldehyde, and B being the radical of a compound which is free of diazonium groups and is capable of condensation with formaldehyde, particularly of an aromatic amine, a phenol, a phenol ether, an aromatic thioether, an aromatic hydrocarbon, an aromatic heterocyclic compound or an organic acid amide.

Inventors

  • 👤 Hans-Joachim Schlosser
  • 👤 Joerg Strack

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-06 06:32
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/26; G03F7/30; G03F7/32

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 117 words
A method for producing waterless offset printing plates, comprising the steps of: coating a support with a photosensitive layer based on a diazonium salt polycondensation product; coating said photosensitive layer with a layer of silicone elastomer; crosslinking said silicone elastomer to produce an unexposed printing plate; imagewise exposing said unexposed printing plate to radiation; and developing said exposed plate in a developer consisting essentially of from 50 to 100% by weight of at least one compound of the general formula R -- (O -- CH.sub.2 -- CH.sub.2 -- ).sub.n -- O -- R wherein R denotes C m H 2m+1' n denotes an integer form 1 to 25, and M denotes an integer form 1 to 5.
Claim 2
Independent Claim 117 words
A method for producing waterless offset printing plates, comprising the steps of: coating a support with a photosensitive layer based on a diazonium salt polycondensation product; coating said photosensitive layer with a layer of silicone elastomer; crosslinking said silicone elastomer to produce an unexposed printing plate; imagewise exposing said unexposed printing plate to radiation; and developing said exposed plate in a developer consisting essentially of from 50 to 100% by weight of at least one compound of the general formula R -- (O -- CH.sub.2 -- CH.sub.2 -- ).sub.n -- O -- R wherein R denotes C m H 2m+1' n denotes an integer form 1 to 25, and M denotes an integer form 1 to 5.
Claim 3
Dependent Claim 16 words
A developing method as claimed in claim 1, additionally consisting essentially of at least one surfactant.
Claim 4
Dependent Claim 22 words
A developing method as claimed in claim 2, said developer consisting essentially of not more than 15% by weight of said surfactant.
Claim 5
Dependent Claim 16 words
A developing method as claimed in claim 1, additionally consisting essentially of at least one alcohol.
Claim 6
Dependent Claim 21 words
A developing method as claimed in claim 4, said developer consisting essentially of 5 to 40% by weight of said alcohol.
Claim 7
Dependent Claim 22 words
A developing method as claimed in claim 1, said developer additionally consisting essentially of not more than 20% by weight of water.
Claim 8
Dependent Claim 32 words
A developing method as claimed in claim 1, said developer additionally consisting essentially of at least one selected from the group consisting of N,N-dimethylacetamide, N-methylpyrrolidone, N-hexylpyrrolidone, N,N-dimethylformamide, dimethylsulfoxide, butyrolactone and aliphatic hydrocarbons.
Claim 9
Dependent Claim 38 words
A developing method as claimed in claim 7, said developer comprising not more than 50% by weight of said at least one compound selected from the group consisting of N,N-dimethylacetamide, N-methylpyrrolidone, N-hexylpyrrolidone, N,N-dimethylformamide, dimethylsulfoxide, butyrolactone and aliphatic hydrocarbons.
Claim 10
Dependent Claim 73 words
A developing method as claimed in claim 1, wherein said diazonium salt polycondensation product comprises recurrent A-N 2 X and B units that are mutually linked by bridge members that are derived from carbonyl compounds capable of condensation, A is the radical of an aromatic diazonium compound capable of condensation with formaldehyde, and B is the radical of a compound which is free of diazonium groups and is capable of condensation with formaldehyde.
Claim 11
Dependent Claim 44 words
A developing method as claimed in claim 9, wherein B consists of at least one member selected from the group consisting of an aromatic amine, a phenol, a phenol ether, an aromatic thioether, an aromatic hydrocarbon, an aromatic heterocyclic compound and anorganic acid amide.
Claim 12
Dependent Claim 15 words
A developing method as claim in claim 9, wherein said bridge members comprise methylene groups.
Claim 13
Dependent Claim 18 words
A developing method as claimed in claim 1, comprising a mixture of compounds corresponding to the general formula.

References Cited (Backward Citations)

US3677178A Cited
US3511178A Cited
US3849392A Cited
US3867147A Cited
US3894873A Cited
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US4378423A Cited
US4642283A Cited
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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1993-10-15 1994-04-16 1994-10-16 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1997-10-15 1998-04-16 1998-10-16 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2001-10-15 2002-04-16 2002-10-16 $7700.00 Window Closed / Lapsed

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