Inkjet-imageable lithographic printing members and methods of preparing and imaging them

Abstract

Lithographic printing plates are imaged using an inkjet printer to imagewise apply a chemical or masking agent onto the plate surface. In some embodiments, the chemical causes an affinity change, thereby facilitating lithographic printing.

1 - 15 . (canceled) 
   
   
       16 . A method of imaging a lithographic printing member, the method comprising the steps of:
 (a) providing a printing member comprising a photosensitive top layer having a first lithographic affinity and a layer thereunder having a second lithographic affinity opposite to the first lithographic affinity, the top layer comprising a material which, upon subjection to an imaging fluid, becomes crosslinkable by exposure to actinic radiation;   (b) dispensing the imaging fluid in an imagewise pattern;   (c) exposing the printing member to actinic radiation, thereby crosslinking portions of the top layer that have received imaging fluid;   (d) subjecting the printing member to a solvent, the solvent disrupting non-image, uncrosslinked portions of the top layer; and   (e) removing the non-image portions of the top layer, thereby creating an imagewise lithographic pattern on the printing member.   
   
   
       17 . The method of  claim 16  wherein the solvent comprises an aqueous fluid. 
   
   
       18 . The method of  claim 16 , wherein the first lithographic affinity is hydrophilicity and the second lithographic affinity is oleophilicity. 
   
   
       19 . The method of  claim 16 , wherein the first lithographic affinity is oleophilicity and the second lithographic affinity is hydrophilicity. 
   
   
       20 . The method of  claim 16 , wherein the top layer comprises at least one crosslinkable moiety. 
   
   
       21 . The method of  claim 20 , wherein the crosslinkable moiety is selected from the group consisting of multifunctional acrylic monomer, multifunctional acrylic oligomer, multifunctional acrylic macromer, and combinations thereof. 
   
   
       22 . The method of  claim 16 , wherein the imaging fluid comprises a multifunctional amine. 
   
   
       23 . The method of  claim 16 , wherein the top layer comprises at least one photo-polymerizable moiety and a first component of a two-component photo-polymerization initiating system. 
   
   
       24 . The method of  claim 23 , wherein the imaging fluid comprises a second component of a two-component photo-polymerization initiating system. 
   
   
       25 - 95 . (canceled)