# US 8,785,109 B2 · Method of developing a lithographic printing plate including post heating > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,785,109 B2 - Document ID: US8785109B2 - Status: Granted - Kind: B2 - Application number: 13/413,280 - Filed: 2012-03-06 - Published: 2012-07-26 - Granted: 2014-07-22 - Earliest claimed: 2009-09-28 - Assignees: Anocoil Corporation - Applicants: Howard A. Fromson; William J. Ryan - Inventors: Howard A. Fromson; William J. Ryan - Web page: https://patentgrep.com/patent/US8785109B2 ## CPC - B41C 1/1008: {by removal or destruction of lithographic material on the lithographic support, e.g. by laser or spark ablation; by the use of materials rendered soluble or insoluble by heat exposure, e.g. by heat produced from a light to heat transforming system; by on-the-press exposure or on-the-press development, e.g. by the fountain of photolithographic materials} - B41C 1/1075: {Mechanical aspects of on-press plate preparation (B41C1/1008 - B41C1/1066 take precedence)} - G03F 7/2022: {Multi-step exposure, e.g. hybrid; backside exposure; blanket exposure, e.g. for image reversal; edge exposure, e.g. for edge bead removal; corrective exposure} - G03F 7/3035: {from printing plates fixed on a cylinder or on a curved surface; from printing cylinders} - G03F 7/36: Imagewise removal not covered by groups G03F7/30 - G03F7/34, e.g. using gas streams, using plasma - B41C 1/1016: {characterised by structural details, e.g. protective layers, backcoat layers or several imaging layers} - B41C 2201/02: Cover layers; Protective layers - B41C 2210/04: Negative working, i.e. the non-exposed (non-imaged) areas are removed - B41C 2210/08: Developable by water or the fountain solution - B41C 2210/24: characterised by a macromolecular compound or binder obtained by reactions involving carbon-to-carbon unsaturated bonds, e.g. acrylics, vinyl polymers - B41C: PROCESSES FOR THE MANUFACTURE OR REPRODUCTION OF PRINTING SURFACES (photomechanical processes for producing printing surfaces G03F; photoelectrical processes for producing printing surfaces G03G) - G03F: PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR; (phototypographic composing devices B41B; photosensitive materials or processes for photographic purposes G03C; electrophotography, sensitive layers or processes therefor G03G) ## Abstract A method for producing a printable lithographic plate from a negative working, radiation imageable plate having an oleophilic resin coating that reacts to radiation by cross linking and is non-ionically adhered to a hydrophilic substrate. Steps include imagewise radiation exposing the coating to produce an imaged plate having partially reacted image areas including unreacted coating material, and completely unreacted nonimage areas; developing the plate by removing only the unreacted, nonimage areas from the substrate while retaining unreacted material in the image areas; and blanket exposing the developed plate with a source of energy which further reacts the retained unreacted material in the image areas. A plate with a coating containing resin particles can be imaged to produce initial cross-linking, then mechanically developed. Hardening of the imaged areas is completed with a relatively intense post-heating at 160 deg. C., which further cross links the monomer and fuses the resin particles. ## Claims ### Claim 1 A method for pre-press production of a printable lithographic plate from a negative working, radiation imageable plate having an oleophilic resin coating that reacts to radiation by cross linking and is non-ionically adhered to a hydrophilic substrate, comprising: imagewise radiation exposing the coating to produce an imaged plate having partially reacted image areas including unreacted coating material, and completely unreacted nonimage areas; developing the plate by removing only unreacted, nonimage areas of the resin coating from the substrate without dissolution of any of the resin coating while retaining unreacted material in the image areas; and blanket exposing the developed plate with an external source of energy which further reacts the retained unreacted material in the image areas. ### Claim 2 (depends on 1) The method of claim 1, wherein the plate has a nominal coating weight of the resin coating before developing and the image areas retain the nominal coating weight through completion of the blanket exposure. ### Claim 3 (depends on 1) The method of claim 1, wherein the plate is developed by application of mechanical force on all the coating to mechanically dislodge only the nonimage areas as particles from the substrate while the image areas remain intact. ### Claim 4 (depends on 3) The method of claim 3, wherein the coating is solvent soluble but not soluble or dispersible in any of water, press ink, or press fountain solution; and the application of mechanical force dislodges the nonimage areas as particles from the substrate without dissolution or dispersion of any of the coating material. ### Claim 5 (depends on 1) The method of claim 1, wherein the radiation exposure produces dot image areas in the imaged plate that have increased adhesion to the substrate and increased internal cohesion relative to the unimaged areas; the dot image areas have boundaries defined by the imagewise radiation exposure; and the increased adhesion and cohesion from the radiation exposure is sufficient to maintain the dot boundaries throughout development of the plate. ### Claim 6 (depends on 1) The method of claim 1, wherein no active ingredient in the coating is soluble in water and development is by mechanical impingement in water. ### Claim 7 (depends on 6) The method of claim 6, wherein no ingredient in the coating is soluble in water. ### Claim 8 (depends on 1) The method of claim 1, wherein the coating is sensitive to infra-red radiation, the imagewise radiation exposure is with infra-red radiation at an energy level in the range of 50-150 mj/cm2, and the blanket exposure is with thermal energy at a temperature above 120 deg. C. ### Claim 9 (depends on 1) The method of claim 1, wherein no ingredient in the coating is water soluble; the imaged plate is developed by mechanical impingement in a water environment that removes unimaged areas of the coating from the substrate as undissolved particles; and the water environment includes at least one surfactant for inhibiting the removed particles from agglomerating. ### Claim 10 A method for pre-press development of a negative working lithographic printing plate having a radiation sensitive, oleophilic resin coating adhered to a hydrophilic substrate, comprising: initially exposing the coating to a pattern of radiation energy, thereby producing an imaged plate having image areas where the coating is partially cross-linked by reaction with the radiation energy and nonimage areas where the coating is unaffected by the radiation energy; developing the plate by removing only the nonimage areas of the coating from the substrate without chemical reaction, thereby producing a pattern of said partially cross-linked oleophilic coating in the image areas and hydrophilic substrate where the nonimage areas were removed; and finally exposing the developed plate to a source of energy which further reacts and cross links the image areas. ### Claim 11 (depends on 10) The method of claim 10, wherein the coating is sensitive to infra-red radiation, the initial exposure is with infra-red radiation, and the final exposure is with thermal energy. ### Claim 12 (depends on 10) The method of claim 10, wherein the coating on the imageable plate is non-ionically adhered to the substrate and has a cohesion that is greater than the adhesion to the substrate; the developing is by application of mechanical force to disrupt and dislodge the nonimage areas as particles from the substrate; and the initial exposure increases the adhesion of the image areas to the substrate to resist removal by the mechanical force that disrupts and dislodges the nonimage areas from the substrate. ### Claim 13 (depends on 10) The method of claim 10, wherein the imageable plate has a nominal coating weight of the resin coating and the image areas substantially retain the nominal coating weight throughout the initial exposure, development, and final exposure. ### Claim 14 (depends on 12) The method of claim 12, wherein the mechanical force is applied by a rotating brush in a water environment. ### Claim 15 (depends on 14) The method of claim 14, including distributing the particles in an environment of flowing water; filtering the particles from the water flow; and recirculating the filtered water into said water environment. ### Claim 16 (depends on 10) The method of claim 10, wherein the nonimage areas of the coating are removed from the substrate without dissolution of any of the coating. ### Claim 17 (depends on 12) The method of claim 12, wherein the nonimage areas of the coating are removed from the substrate without dissolution or dispersion of any of the coating. ### Claim 18 (depends on 12) The method of claim 12, wherein the coating is solvent soluble but not soluble or dispersible in any of water, press ink, or press fountain solution; and the application of mechanical force disrupts and dislodges all of the nonimage areas as particles from the substrate without dissolution of any of the coating material. ### Claim 19 A method for pre-press development of a negative working lithographic printing plate having an oleophilic resin coating that has a cross-linking reaction to imaging radiation, is solvent soluble but not water soluble, has a nominal coating weight, a coating cohesion, and non-ionic adhesion to a hydrophilic substrate that is less than said coating cohesion, comprising: initially exposing the coating to a pattern of radiation energy, producing an imaged plate having image areas where the radiation energy produces an initial cross-linking reaction in the coating and thereby increases the cohesion and adhesion of the coating, and nonimage areas where the coating is unaffected by the radiation energy; without heating the imaged plate, developing the imaged plate in a water environment by application of mechanical force to dislodge and remove the nonimage areas as undissolved particles from the substrate, thereby producing a pattern of initially cross-linked oleophilic coating in the image areas that retain the nominal coating weight and hydrophilic substrate where the nonimage areas were removed; and finally exposing the developed plate to a blanket source of energy to produce additional cross-linking reactions in the image areas. ### Claim 20 (depends on 19) The method of claim 19, wherein: the coating is sensitive to infra-red radiation; the initial radiation exposure is with infra-red radiation at an energy level in the range of 50-150 mj/cm2; the final exposure and said additional cross-linking is with thermal energy at a temperature above 120 deg. C. to produce a final cross-linking of at least 50% in the image areas. ### Claim 21 (depends on 20) The method of claim 20, wherein the initial radiation exposure is at an energy level less than 100 mj/cm2. ### Claim 22 (depends on 21) The method of claim 21, wherein the final exposure is at a temperature in the range of 120 to 160 deg. C.