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 agent onto the plate surface. The chemical causes a change that facilitates lithographic printing.

1 . A lithographic printing member comprising a soluble and top layer having a first lithographic affinity and a layer thereunder also having the first lithographic affinity, the top layer being responsive to an imaging fluid by undergoing a phase change to an insoluble state having a second lithographic affinity opposite to the first lithographic affinity.  
     
     
         2 . The printing member of  claim 1 , wherein the top layer is water-soluble and hydrophilic prior to the phase change and water-insoluble and oleophilic following the phase change.  
     
     
         3 . The printing member of  claim 1 , wherein the top layer is water-soluble and oleophilic prior to the phase change and water-insoluble and hydrophilic following the phase change.  
     
     
         4 . The printing member of  claim 1 , wherein the top layer comprises a polymer selected from the group consisting of polyvinyl phosphonic acid, polyvinyl alcohol comprising amino-moieties, and any polymer comprising at least one of carboxylic acid moieties, sulfonic acid moieties, and phosphonic acid moieties.  
     
     
         5 . The printing member of  claim 1 , wherein the imaging fluid to which the printing member is responsive comprises an esterifying agent.  
     
     
         6 . The printing member of  claim 5 , wherein the esterifying agent comprises a chemical compound selected from the group consisting of tetramethylammonium hydroxide, phenyltrimethylammonium hydroxide, trimethylsulfonium hydroxide, trimethylsulfoxonium hydroxide, and 1,3-(bistripropylammonium)xylene hydroxide.  
     
     
         7 . The printing member of  claim 1 , wherein the imaging fluid to which the printing member is responsive comprises an alkylating agent.  
     
     
         8 . The printing member of  claim 1 , wherein the imaging fluid to which the printing member is responsive comprises a polymer comprising a quaternary ammonium salt.  
     
     
         9 . The printing member of  claim 1  further comprising a crosslinked hydrophilic intermediate layer disposed between the top layer and the underlying layer.  
     
     
         10 . A system for lithographic printing comprising: 
 (a) a printing member comprising a soluble top layer and a layer thereunder, the top layer having a first lithographic affinity and the underlying layer also having the first lithographic affinity, and    (b) an imaging fluid;    wherein the top layer responds to the imaging fluid by undergoing a phase change to an insoluble state having having a second lithographic affinity opposite to the first lithographic affinity.    
     
     
         11 . The system of  claim 10 , wherein the top layer is water-soluble and hydrophilic prior to the phase change and water-insoluble and oleophilic following the phase change.  
     
     
         12 . The system of  claim 10 , wherein the top layer is water-soluble and oleophilic prior to the phase change and water-insoluble and hydrophilic following the phase change.  
     
     
         13 . The system of  claim 10 , wherein the top layer comprises a polymer selected from the group consisting of polyvinyl phosphonic acid, polyvinyl alcohol comprising amino-moieties, and any polymer comprising at least one of carboxylic acid moieties, sulfonic acid moieties, and phosphonic acid moieties.  
     
     
         14 . The system of  claim 10 , wherein the imaging fluid comprises an esterifying agent.  
     
     
         15 . The system of  claim 14 , wherein the esterifying agent comprises a chemical compound selected from the group consisting of tetramethylammonium hydroxide, phenyltrimethylammonium hydroxide, trimethylsulfonium hydroxide, trimethylsulfoxonium hydroxide, and 1,3-(bistripropylammonium)xylene hydroxide.  
     
     
         16 . The system of  claim 10 , wherein the imaging fluid comprises an alkylating agent.  
     
     
         17 . The system of  claim 10 , wherein the imaging fluid comprises a polymer comprising a quaternary ammonium salt.  
     
     
         18 . The system of  claim 8 , wherein the printing member further comprises a crosslinked hydrophilic intermediate layer disposed between the top layer and the underlying layer.  
     
     
         19 . A method of imaging a lithographic printing member, the method comprising the steps of: 
 (a) providing a printing member comprising a soluble and top layer having a first lithographic affinity and a layer thereunder also having the first lithographic affinity, the top layer being responsive to an imaging fluid by undergoing a phase change to an insoluble state having a second lithographic affinity opposite to the first lithographic affinity;    (b) dispensing the imaging fluid in an imagewise pattern, the imaging fluid chemically reacting with the top layer and inducing the phase change;    (c) subjecting the printing member to a solvent, the solvent dissolving soluble portions of the top layer; and    (d) removing the soluble portions of the top layer, thereby creating an imagewise lithographic pattern on the printing member.    
     
     
         20 . The method of  claim 19 , wherein the top layer is water-soluble and hydrophilic prior to the phase change and water-insoluble and oleophilic following the phase change, the solvent comprising an aqueous fluid.  
     
     
         21 . The method of  claim 19 , wherein the top layer is water-soluble and oleophilic prior to the phase change and water-insoluble and hydrophilic following the phase change, the solvent comprising an aqueous fluid.  
     
     
         22 . The method of  claim 19 , wherein the top layer comprises a polymer selected from the group consisting of polyvinyl phosphonic acid, polyvinyl alcohol comprising amino-moieties, and any polymer comprising at least one of carboxylic acid moieties, sulfonic acid moieties, and phosphonic acid moieties.  
     
     
         23 . The method of  claim 19 , wherein the imaging fluid comprises an esterifying agent.  
     
     
         24 . The method of  claim 23 , wherein the esterifying agent comprises a chemical compound selected from the group consisting of tetramethylammonium hydroxide, phenyltrimethylammonium hydroxide, trimethylsulfonium hydroxide, trimethylsulfoxonium hydroxide, and 1,3-(bistripropylammonium)xylene hydroxide.  
     
     
         25 . The method of  claim 19 , wherein the imaging fluid comprises an alkylating agent.  
     
     
         26 . The method of  claim 19 , wherein the imaging fluid comprises a polymer comprising a quaternary ammonium salt.  
     
     
         27 . The method of  claim 19 , wherein the printing member further comprises a crosslinked hydrophilic intermediate layer disposed between the top layer and the underlying layer.  
     
     
         28 . The method of  claim 19 , flurther comprising a step of heating the printing member between steps (b) and (c).  
     
     
         29 . A lithographic printing member comprising a dispersible 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 being responsive to an imaging fluid by undergoing a phase change from a dispersible state to an insoluble state.  
     
     
         30 . The printing member of  claim 29 , wherein the top layer is water-dispersible and oleophilic, and responsive to an imaging fluid by undergoing a phase change to a water-insoluble state.  
     
     
         31 . The printing member of  claim 29 , wherein the top layer is water-dispersible and hydrophilic, and responsive to an imaging fluid by undergoing a phase change to a water-insoluble state.  
     
     
         32 . The printing member of  claim 29 , wherein the top layer comprises a water-dispersible polymer.  
     
     
         33 . The printing member of  claim 32 , wherein the water-dispersible polymer comprises an epoxy resin.  
     
     
         34 . The printing member of  claim 29 , wherein the imaging fluid comprises a multiflnctional amine.  
     
     
         35 . The printing member of  claim 29 , wherein the imaging fluid comprises a tetra-carboxylic acid.  
     
     
         36 . The printing member of  claim 29 , wherein the printing member fiuther comprises a crosslinked hydrophilic intermediate layer disposed between the top layer and the underlying layer.  
     
     
         37 . The printing member of  claim 36 , wherein the intermediate layer comprises PVOH—ZrOH.  
     
     
         38 . A system for lithographic printing comprising: 
 (a) a printing member comprising a dispersible top layer and a layer thereunder, the top layer having a first lithographic affinity and the underlying layer having a second lithographic affinity opposite to the first lithographic affinity, and    (b) an imaging fluid;    wherein the top layer responds to the imaging fluid by undergoing a phase change from a dispersible state to an insoluble state.    
     
     
         39 . The system of  claim 38 , wherein the top layer is water-dispersible and oleophilic, and responsive to an imaging fluid by undergoing a phase change to a water-insoluble state.  
     
     
         40 . The system of  claim 38 , wherein the top layer is water-dispersible and hydrophilic, and responsive to an imaging fluid by undergoing a phase change to a water-insoluble state.  
     
     
         41 . The system of  claim 38 , wherein the top layer comprises a water-dispersible polymer.  
     
     
         42 . The system of  claim 41 , wherein the water-dispersible polymer comprises an epoxy resin.  
     
     
         43 . The system of  claim 38 , wherein the imaging fluid comprises a multifunctional amine.  
     
     
         44 . The system of  claim 38 , wherein the imaging fluid comprises a tetra-carboxylic acid.  
     
     
         45 . The system of  claim 38 , wherein the printing member flurther comprises a crosslinked hydrophilic intermediate layer disposed between the top layer and the substrate.  
     
     
         46 . The system of  claim 45 , wherein the intermediate layer comprises PVOH—ZrOH.  
     
     
         47 . A method of imaging a lithographic printing member, the method comprising the steps of: 
 (a) providing a printing member comprising a dispersible 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 being responsive to an imaging fluid by undergoing a phase change from a dispersible state to an insoluble state;    (b) dispensing the imaging fluid in an imagewise pattern, the imaging fluid chemically reacting with the top layer and inducing the phase change;    (c) subjecting the printing member to a solvent, the solvent dissolving dispersible portions of the top layer; and    (d) removing the dispersible portions of the top layer, thereby creating an imagewise lithographic pattern on the printing member.    
     
     
         48 . The method of  claim 47 , wherein the solvent comprises an aqueous fluid.  
     
     
         49 . The method of  claim 48 , wherein the top layer is water-dispersible and oleophilic, and responsive to an imaging fluid by undergoing a phase change to a water-insoluble state.  
     
     
         50 . The method of  claim 48 , wherein the top layer is water-dispersible and hydrophilic, and responsive to an imaging fluid by undergoing a phase change to a water-insoluble state.  
     
     
         51 . The method of  claim 47 , wherein the top layer comprises a water-dispersible polymer.  
     
     
         52 . The method of  claim 51 , wherein the water-dispersible polymer comprises an epoxy resin.  
     
     
         53 . The method of  claim 47 , wherein the imaging fluid comprises a multifunctional amine.  
     
     
         54 . The method of  claim 47 , wherein the imaging fluid comprises a tetra-carboxylic acid.  
     
     
         55 . The method of  claim 47 , wherein the printing member further comprises a crosslinked hydrophilic intermediate layer disposed between the top layer and the substrate.  
     
     
         56 . The method of  claim 55 , wherein the intermediate layer comprises PVOH—ZrOH.