US 5,849,462 A · Negative-acting no-process printing plates

Abstract

A photosensitive composition is prepared containing a polymer of the formula B(X)(Y) wherein B represents an organic backbone, each X independently is an acidic group or salt thereof and each Y independently is a photocurable group and a photoinitating compound or compounds. Preferably, free-radically polymerizable multi-functional monomer and/or oligomer is added to the photosensitive composition. The photosensitive composition can be coated on a suitable substrate for planographic printing plate applications. Imagewise irradiation causes the light struck regions to photocure, becoming insoluble in aqueous and organic mediums, while the non-light struck regions remain highly soluble/dispersable. Printing plates of this construction do not require processing prior to being run on a press.

Claims11

Dependent claims

A photosensitive composition comprising:

(a) a reactive, acid functional polymer of the formula B(X)(Y) prepared by reacting a polyalkenoic acid homopolymer having acidic groups present in an amount between 0.75 and 1.6 ephr with a coupling compound selected from the group consisting of allyl isocyanate and 2-isocyanatoethylmethacrylate, wherein B represents an organic backbone of carbon-carbon bonds, each X independently is said acidic group present in an amount of between 0.02 and 0.8 ephr, and each Y independently is a photocurable group present in an amount of between 0.35 and 0.8 ephr;
and
(b) a photoinitiator which initiates crosslinking of the reactive acid functional polymer upon exposure to radiation.

Dependencies are inferred from the claim text.

Facts

Application

08/915,378Filed 20 Aug 1997 · continuation

Priority

27 Apr 1995

Granted

15 Dec 1998

Term ends

Not estimatedThe source records don’t support an estimate.

Classification12 codes

G03F 7/027
Photosensitive materials: non-macromolecular photopolymerisable compounds having carbon-to-carbon double bonds, e.g. ethylenic compounds
B41C 1/1041
For lithographic printing; Master sheets for transferring a lithographic image to the forme: by modification of the lithographic properties…
G03F 7/033
With binders: the binders being polymers obtained by reactions only involving carbon-to-carbon unsaturated bonds, e.g. vinyl polymers
G03F 7/0388
Macromolecular compounds which are rendered insoluble or differentially wettable: with ethylenic or acetylenic bands in the side chains of the…

Negative-acting no-process printing plates

Life of this patent

Negative-acting no-process printing plates

Life of this patent

Abstract

Claims11