On-press development of thermosensitive lithographic printing member
OwnerGary Ganghui Tenginventor
Life of this patent
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Abstract
Method of on-press developing a thermosensitive lithographic printing member with ink and/or fountain solution is described. The printing member comprises on a substrate a thermosensitive layer soluble or dispersible in ink and/or fountain solution and capable of hardening upon exposure to an infrared radiation. The printing member can be a pre-coated plate or can be prepared on press by coating a thermosensitive layer onto a substrate that is a sheet material or a seamless sleeve mounted on a plate cylinder or is the surface of a plate cylinder of the lithographic press.
Claims30
A method of lithographically printing images on a receiving medium, comprising in order:
- (a) providing on a lithographic press a lithographic printing member comprising (i) a substrate that is a sheet material or a seamless sleeve mounted on a plate cylinder or is the surface of a plate cylinder of the lithographic press;
- and (ii) a thermosensitive layer capable of hardening through polymerization upon exposure to an infrared radiation;
- wherein said thermosensitive layer is soluble or dispersible in ink (for waterless plate) or ink and/or fountain solution (for wet plate), and at least the hardened areas of said thermosensitive layer exhibit an affinity or aversion substantially opposite to the affinity or aversion of said substrate to at least one printing liquid selected from the group consisting of ink and an abhesive fluid for ink;
- (b) imagewise exposing the plate with the infrared radiation to cause hardening of the thermosensitive layer in the exposed areas;
- and
- (c) operating said press to contact said exposed plate with ink and/or fountain solution to remove the thermosensitive layer in the non-hardened areas, and to lithographically print images from said plate to the receiving medium.
A method of lithographically printing images on a receiving medium, comprising in order:
- (a) providing on a lithographic press a hydrophilic substrate that is a sheet material or a seamless sleeve mounted on a plate cylinder or is the surface of a plate cylinder of the lithographic press;
- (b) coating onto said substrate an oleophilic thermosensitive layer comprising a polymerizable monomer, an initiator capable of initiating the polymerization of said monomer, and an infrared absorbing dye;
- wherein said thermosensitive layer is soluble or dispersible in ink and/or fountain solution and is capable of hardening upon exposure to an infrared radiation;
- (c) imagewise exposing the plate with the infrared radiation to cause hardening of the thermosensitive layer in the exposed areas;
- and
- (d) operating said press to contact said exposed plate with ink and/or fountain solution to remove the thermosensitive layer in the non-hardened areas, and to lithographically print images from said plate to the receiving medium.
A method of lithographically printing images on a receiving medium, comprising in order:
- (a) providing a lithographic plate comprising (i) a hydrophilic aluminum substrate, and (ii) an oleophilic thermosensitive layer comprising a polymer, a polymerizable monomer, an initiator capable of initiating the polymerization of said monomer, and an infrared absorbing dye;
- wherein said thermosensitive layer is soluble or dispersible in ink and/or fountain solution, and capable of hardening upon exposure to an infrared radiation;
- (b) imagewise exposing the plate with the infrared radiation according to digital imaging information to cause hardening of the thermosensitive layer in the exposed areas;
- and
- (c) contacting said exposed plate with ink and/or fountain solution on a lithographic press to remove the thermosensitive layer in the non-hardened areas, and to lithographically print images from said plate to the receiving medium.
Dependencies are inferred from the claim text.