Post Imaging Process Patents (Class 430/309)
  • Patent number: 4496647
    Abstract: An image-forming laminated plate, particularly a dry planographic printing unprocessed plate, comprising a base substrate, a photosensitive layer containing a substance with quinonediazide structure and a silicone rubber layer in laminating order is treated with a base after imagewise exposure. In addition, the image-forming laminated plate may be subjected to a whole surface slight exposure to the extent that 5 to 60 molar % of the quinonediazide structure in the photosensitive layer to be exposed is photo-decomposed into carboxylic acid structure before or after the usual imagewise exposure for obtaining a negative working plate, or the image-forming laminated plate may be subjected to a imagewise slight exposure to the same extent without the usual imagewise exposure for obtaining a positive working plate.
    Type: Grant
    Filed: July 18, 1983
    Date of Patent: January 29, 1985
    Assignee: Toray Industries, Inc.
    Inventors: Norio Kawabe, Mikio Tsuda, Sadao Kobashi
  • Patent number: 4487827
    Abstract: The invention relates to a process for the burning-in of positive-working, light-sensitive layers, containing diazo compounds, during the preparation of offset printing forms, by heating the printing plate. In this process, the light-sensitive layer is treated, after exposure and development, with electromagnetic radiation having an infrared fraction, a fraction in the visible region, and an ultraviolet fraction.
    Type: Grant
    Filed: March 15, 1982
    Date of Patent: December 11, 1984
    Assignee: Hoechst Aktiengesellschaft
    Inventor: G/u/ nter Berghaeuser
  • Patent number: 4478931
    Abstract: A permanent curl is provided in flexographic printing plates comprising a flexible sheet support and a photosensitive layer of a photopolymerizable elastomeric composition having a dry thickness of about 0.005 to 0.250 inch wherein after liquid development the printing plate is dried, 20.degree. to 80.degree. C. for at least 0.25 hour, and is postexposed by overall actinic radiation exposure for 1 to 30 minutes, at least the postexposure occurring while the printing plate is present on a curved surface, e.g., a printing cylinder. The process is useful for rubber and block copolymer-containing printing plates.
    Type: Grant
    Filed: September 27, 1982
    Date of Patent: October 23, 1984
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Michael G. Fickes, Alan L. Shobert
  • Patent number: 4469776
    Abstract: A developing solution for a light-sensitive printing plate having an o-quinonediazide-containing light-sensitive layer is disclosed. The developing solution is comprized of an aqueous solution of alkali silicate and a chelating agent. By including the chelating agent within the developing solution it is possible to carry out development utilizing water which contains typical impurities such as insoluble calcium silicate or magnesium silicate for a long period of time which substantially has no formation of insoluble matter within the developing machine. Use of the developing solution substantially eliminate the formation of any deposit within the spraying pipes and nozzles of the developing machine which it is used in connection with.
    Type: Grant
    Filed: April 29, 1983
    Date of Patent: September 4, 1984
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Hiroshi Matsumoto, Nobuyuki Kita
  • Patent number: 4467027
    Abstract: A developer composition of an alkaline aqueous solution containing a reducing inorganic salt, typically an alkali metal salt of sulfurous acid such as sodium sulfite, is found to be applicable for development of a lithographic printing plate material containing a photosensitive o-quinonediazide compound and an organic polymer, with reduced deterioration in developing capacity caused by the air and enhanced stability with lapse of time. In particular, a developer composition composed of an alkaline aqueous solution of pH 11 or higher containing a water-soluble sulfurous acid salt is effective for developing both of a lithographic printing plate material having a nega-type photosensitive layer containing a photosensitive diazo compound and an organic polymer, and a lithographic printing plate material having a posi-type photosensitive layer containing an o-quinonediazide compound and an organic polymer.
    Type: Grant
    Filed: May 20, 1982
    Date of Patent: August 21, 1984
    Assignee: Konishiroku Photo Industry Co., Ltd.
    Inventors: Takeshi Yamamoto, Kiyoshi Goto, Yoshio Kurita, Noriyasu Kita, Naoshi Kunieda
  • Patent number: 4465768
    Abstract: A radiation-sensitive composition comprising an iodine-containing azide compound at least a part of which can be fixed substantially in a polymer by exposure to a radiation and a polymer, or a radiation-sensitive composition comprising an azide compound, an iodine compound at least a part of which can be fixed substantially in a polymer by exposure to a radiation and a polymer. This composition can be subjected to the dry development with oxygen plasma after the exposure followed by heating.
    Type: Grant
    Filed: July 13, 1982
    Date of Patent: August 14, 1984
    Assignee: Hitachi, Ltd.
    Inventors: Takumi Ueno, Hiroshi Shiraishi, Takao Iwayanagi, Takahiro Kohashi, Saburo Nonogaki
  • Patent number: 4460675
    Abstract: Process for preparing flexographic photopolymer elements by passing into the nip of a calender a photopolymer composition mass comprising elastomeric binder, monomeric compound, and photoinitiator and calendering the photopolymer composition either between (1) a support and multilayer cover element consisting essentially of a flexible cover film, optionally a flexible polymeric film, e.g., polyamide, and a layer of elastomeric composition which is photosensitive or becomes photosensitive during or after calendering, or between (2) two supports, one of which is removed prior to contact, e.g., by lamination or pressing, with the multilayer cover element. The flexographic photopolymer elements are useful for flexographic printing, e.g., dry-offset, letterpress printing.
    Type: Grant
    Filed: October 27, 1983
    Date of Patent: July 17, 1984
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Robert R. Gruetzmacher, Stanley H. Munger
  • Patent number: 4456676
    Abstract: Amine compounds or metal-ammine complexes incorporated into developer-incorporated wash-off films stabilize against premature gelatin hardening on aging. Preferred additives are two gelatin amino acids, lysine and arginine.
    Type: Grant
    Filed: June 10, 1983
    Date of Patent: June 26, 1984
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: James M. Ciskowski
  • Patent number: 4455365
    Abstract: A silver halide photographic material for a photomechanical process which has an excellent reduction processing aptitude is disclosed. The material is comprised of a support having a light-sensitive silver halide emulsion layer thereon and a light-insensitive layer disposed outside the silver halide emulsion layer. The light-insensitive layer contains a hydrophilic colloidal binder coated in such an amount per unit area as to be 1.0 or more times that of a hydrophilic colloidal binder contained in the silver halide emulsion layer.
    Type: Grant
    Filed: August 26, 1982
    Date of Patent: June 19, 1984
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Yukihide Urata, Yasuo Kasama, Shigenori Moriuchi, Eiichi Okutsu
  • Patent number: 4452880
    Abstract: A developing process suitable to treat a positive photosensitive lithographic printing plate comprising a photosensitive layer containing, as the photosensitive constituent, an o-quinonediazide compound provided on an aluminium plate. A positive photo-sensitive lithographic printing plate is exposed imagewise and then developed with a developing solution containing an aqueous solution of an alkali metal silicate in which the alkali metal is essentially constituted by potassium. With the method, development treatment can be conducted stably for a long period without generating insolubes in the developing solution even when an extremely large quantity of positive photosensitive lithographic plates are treated.
    Type: Grant
    Filed: May 18, 1982
    Date of Patent: June 5, 1984
    Assignee: Konishiroku Photo Industry Co., Ltd.
    Inventors: Minoru Seino, Atsuo Yamazaki, Toru Aoki, Akihiko Suzuki
  • Patent number: 4452879
    Abstract: Process for improving ozone resistance of photosensitive flexographic relief printing plates prepared from at least 30% by weight of a block copolymer as defined, at least 1% by weight of at least one addition polymerizable ethylenically unsaturated compound, and a polymerization initiator wherein there is applied to the dry relief surface of said plates a solvent solution containing at least 1% by weight of a nickel or zinc dialkyldithiocarbamate compound where alkyl is from 1 to 4 carbon atoms. The treated plates which possess improved ozone resistance are useful for flexographic printing.
    Type: Grant
    Filed: September 13, 1983
    Date of Patent: June 5, 1984
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Michael G. Fickes, Peter F. Warfield
  • Patent number: 4447510
    Abstract: A process for producing relief copies wherein the light-hardenable layer of a light-hardenable copying material, which contains a photopolymerizable mixture, a photodimerizable polymeric compound or a diazonium salt polycondensation product, is exposed to a light image, the exposed layer is subjected to a brief ultrasonic treatment, and the unexposed areas of the layer are thereafter washed away by means of a developer. As a result of the ultrasonic treatment, shorter exposure times may be used and better in-depth hardening of the layer may be achieved.
    Type: Grant
    Filed: May 7, 1982
    Date of Patent: May 8, 1984
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Werner Frass, Klaus Horn
  • Patent number: 4443531
    Abstract: Disclosed are a deletion fluid for offset printing plates which contains an S-triazine compound represented by the following general formula: ##STR1## (wherein R.sub.1 and R.sub.2 represent --SH or --OH and when either one of R.sub.1 or R.sub.2 is --SH, the other may be NHR wherein R is H or --R'---COOH wherein R' is an alkylene group or arylene group) and a method for deletion of undesired portion of images formed on an offset printing plate with said deletion fluid.
    Type: Grant
    Filed: September 27, 1982
    Date of Patent: April 17, 1984
    Assignee: Mitsubishi Paper Mills, Ltd.
    Inventors: Shoji Yamada, Eiji Kanada, Eiji Mathubara
  • Patent number: 4439516
    Abstract: This invention is for a photoresist capable of withstanding temperatures in excess of 200.degree. C. without image distortion. The photoresist comprises a high temperature diazo sensitizer, preferably an ester or amide of an o-quinone diazide sulfonic or carboxylic acid chloride, in a binder comprising a polyvinyl phenol. The sensitizer and polyvinyl phenol react with each other at elevated temperature. The sensitizer has a secondary decomposition temperature and the polyvinyl phenol has a flow temperature at least equal to the temperature where reaction between the two occurs.
    Type: Grant
    Filed: March 15, 1982
    Date of Patent: March 27, 1984
    Assignee: Shipley Company Inc.
    Inventors: George J. Cernigliaro, Charles R. Shipley
  • Patent number: 4436807
    Abstract: This invention relates to a composition for developing photosensitive coatings especially coatings useful in making lithographic printing plates. The developing composition comprises an aqueous solution having a pH of from about 8 to about 12 of(a) a sodium, potassium or lithium salt of octyl, decyl or dodecyl monosulfate; and(b) a sodium, lithium, potassium or ammonium metasilicate salt; and(c) a lithium, potassium, sodium or ammonium borate salt; and(d) an aliphatic dicarboxylic acid, or sodium, potassium or ammonium salt thereof having from 2 to 6 carbon atoms; and(e) di-and/or tri-sodium or -potassium phosphate.
    Type: Grant
    Filed: July 15, 1982
    Date of Patent: March 13, 1984
    Assignee: American Hoechst Corporation
    Inventor: John E. Walls
  • Patent number: 4435491
    Abstract: A process for the production of lithographic printing plates, and a light-sensitive material for use in the process are described. The light-sensitive material comprises an electrically conductive support having a hydrophilic surface, and a positive type light-sensitive layer and a photoconductive insulative layer on the support, wherein the positive type light-sensitive layer and the photoconductive insulative layer are provided on the support as a unit layer or individually in that order, and the photoconductive insulative layer can be charged either positively or negatively. The desired lithographic printing plate can be prepared by treating the light-sensitive material by the simple process of the invention.
    Type: Grant
    Filed: November 25, 1981
    Date of Patent: March 6, 1984
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Takashi Kitamura, Hiroshi Kokado
  • Patent number: 4431724
    Abstract: An offset printing plate is provided comprising a carbon steel substrate with printing and non-printing areas on its surface. The printing areas are made of a light-sensitive top layer material based on derivatives of ortho-naphthoquinonediazide-sulphonic or carboxylic acids or a light-sensitive top layer material comprising a photopolymerizable composition. These printing areas form a relief over the plate surface. The non-printing areas are made of a hydrophilized metal of the substrate hydrophilized carbon steel.A process for making an offset printing plate comprises application, onto a carbon steel substrate, of a light sensitive top layer based on derivatives of ortho-naphthoquinonediazide-sulphonic or carboxylic acids or a light-sensitive top layer comprising a photopolymerizable composition. The thus-applied top layer is dried.
    Type: Grant
    Filed: March 10, 1982
    Date of Patent: February 14, 1984
    Inventors: Jury M. Ovchinnikov, Valentina G. Solokhina, Xenia G. Samoshenkova, Veniamin S. Lapatukhin, Julia I. Belyaeva, Genrietta Y. Krikman, Izabella I. Guschina, Nikolai N. Krutikov, Ljubov I. Sulakova
  • Patent number: 4428659
    Abstract: An apparatus and method in which a coating is wetted with a solvent to initiate dissolution of soluble coating portions and the hydraulic pressure of the solvent at the surface of the coating is repeatedly increased and decreased to assist in the dissolution of the soluble coating portions. A brush with an array of bristles reciprocating in a path perpendicular to the coating may be utilized to produce the increasing and decreasing hydraulic pressure. Also, the coating may be immersed in the solvent to wet it and to initiate dissolution of the soluble coating portions.
    Type: Grant
    Filed: June 2, 1981
    Date of Patent: January 31, 1984
    Assignee: Napp Systems (USA), Inc.
    Inventor: Lawrence E. Howard
  • Patent number: 4423138
    Abstract: There are disclosed resist developers in which additives selected from certain tetraalkylammonium or phosphonium cations, benzyltrialkylammonium or phosphonium cations, and benzyltriphenylammonium or phosphonium cations, are effective in enhancing the developer selectivity.
    Type: Grant
    Filed: January 21, 1982
    Date of Patent: December 27, 1983
    Assignee: Eastman Kodak Company
    Inventor: John R. Guild
  • Patent number: 4421844
    Abstract: Disclosed is a process for the preparation of relief copies, comprising the steps of imagewise irradiating a radiation-sensitive copying material comprising a layer support and a radiation-sensitive layer comprising (a) a compound which upon irradiation splits off acid, and (b) a compound possessing at least one acid-cleavable C--O--C group; heating the imagewise irradiated copying material to a temperature above room temperature for a period of time sufficient to produce an increase in radiation sensitivity of the radiation-sensitive layer; and washing out the irradiated layer areas by means of a developer.
    Type: Grant
    Filed: October 9, 1981
    Date of Patent: December 20, 1983
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Gerhard Buhr, Marie-Luise Geus
  • Patent number: 4416976
    Abstract: This invention relates to a developer solution for the development of exposed light-sensitive reproduction layers comprising a water-insoluble binder and a water-insoluble diazonium salt polycondensation product. As the essential constituents, this developer solution contains glycol ethers, glycol esters and water, in detail--about 30 to 80% of a compound of the formula ##STR1## wherein n=1 to 4 and m=1 to 5; about 3 to 30% of a compound of the formula ##STR2## wherein R.sup.1 and R.sup.2 are acyl groups containing 1 to 4 carbon atoms, or one of the two groups is a hydrogen atom and R.sup.3 is a hydrogen atom or a methyl group; about 0 to 15% of 1,3-dioxolane-2-one or 4-methyl-1,3-dioxolane-2-one; about 0 to 20% of a polyhydric alcohol; about 0 to 10% of an organic or inorganic salt which is soluble in the solvent mixture; and about 5 to 45% of water.
    Type: Grant
    Filed: March 31, 1981
    Date of Patent: November 22, 1983
    Assignee: Hoechst Aktiengesellschaft
    Inventor: Loni Schell
  • Patent number: 4415654
    Abstract: Disclosed is the improvement in post-exposing relief printing plates prepared from photosensitive polymeric compositions which comprises immersing the relief printing plate in a dilute aqueous solution of a persulfate salt and a sufficient amount of a water-soluble carboxylic acid to provide a pH of about 1.5 to about 2.5 during exposure to actinic radiation.
    Type: Grant
    Filed: August 19, 1982
    Date of Patent: November 15, 1983
    Assignee: Hercules Incorporated
    Inventor: Rudolph L. Pohl
  • Patent number: 4414315
    Abstract: Process for making a lithographic printing plate having an oleophilic amplified image prepared by(a) providing a silicated aluminum substrate with a hydrophilic, anionic, negatively charged surface and a layer on said surface of a light sensitive, cationic, positively charged, water soluble diazonium material having at least two reactive sites per molecule, each reactive site being capable of being chemically altered by actinic light or chemically reacted with an anionic material;(b) selectively and incompletely exposing the diazo layer to actinic light to alter only a portion of the reactive sites thereby adhering the diazo material to the substrate in the exposed areas;(c) coupling the diazo layer with an anionic material to reinforce diazo in the exposed areas in situ and remove diazo from the unexposed areas by contacting the substrate after exposure with an anionic material in water in a quantity and for a time sufficient to couple the anionic material with the diazo and dissolve the coupled product from
    Type: Grant
    Filed: June 17, 1981
    Date of Patent: November 8, 1983
    Assignee: Howard A. Fromson
    Inventors: Robert F. Gracia, Howard A. Fromson
  • Patent number: 4411983
    Abstract: By treating an imagewise exposed and developed image-forming material comprising a support and a light-sensitive resin composition layer with organic solvents miscible with water or with a mixture of water and organic solvents miscible with water, elimination of non-image areas is completed.
    Type: Grant
    Filed: March 11, 1982
    Date of Patent: October 25, 1983
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Yasuo Washizawa, Fumiaki Shinozaki, Tomoaki Ikeda, Sho Nakao
  • Patent number: 4407862
    Abstract: A method of preparing a letterpress printing plate from a liquid photopolymer using an air knife to etch out the unpolymerized liquid to leave the relief image. A new printing plate substrate is used that has a laminae that is paper and a lamina that is a sealing coat on the paper. The paper is a special paper known as tag stock that is 5 to 20 mils thick, has tensile strengths of at least 30 pounds per inch in width in the press direction and at least 20 pounds per inch in width in the cross press direction, and fibers that are independently colored with a dark color having a good light absorption/reflectivity ratio.
    Type: Grant
    Filed: October 29, 1981
    Date of Patent: October 4, 1983
    Assignee: W. R. Grace & Co.
    Inventors: Forrest Wessells, Joseph Startari, Michael E. Estes
  • Patent number: 4403029
    Abstract: Stripping compositions for removing resist materials from substrates comprise compositions of dimethylacetamide or dimethylformamide or a mixture thereof and a tetrahydrothiophene 1,1-dioxide compound.
    Type: Grant
    Filed: September 2, 1982
    Date of Patent: September 6, 1983
    Assignee: J. T. Baker Chemical Company
    Inventors: Irl E. Ward, Jr., Lisa G. Hallquist, Thomas J. Hurley
  • Patent number: 4401748
    Abstract: Stripping compositions for removing resist materials from substrates comprise compositions of a 2-pyrrolidinone compound and tetrahydrofuran compound. Either or both of polyethylene glycol and a diethylene glycol monoalkyl ether may be added to provide even more effective stripping compositions.
    Type: Grant
    Filed: September 7, 1982
    Date of Patent: August 30, 1983
    Assignee: J. T. Baker Chemical Company
    Inventors: Irl E. Ward, Jr., Lisa G. Hallquist
  • Patent number: 4401747
    Abstract: Stripping compositions for removing resist materials from substrates comprise compositions of a 2-pyrrolidinone compound and a dialkyl sulfone compound. Either or both of polyethylene glycol and a diethylene glycol monoalkyl ether may be added to provide even more effective stripping compositions.
    Type: Grant
    Filed: September 2, 1982
    Date of Patent: August 30, 1983
    Assignee: J. T. Baker Chemical Company
    Inventors: Irl E. Ward, Jr., Lisa G. Hallquist, Thomas J. Hurley
  • Patent number: 4400460
    Abstract: Process for providing improved solvent resistant surfaces of relief flexographic printing plates prepared by imagewise exposure and liquid development of the unexposed areas of a layer of photosensitive elastomeric composition comprising a high molecular weight butadiene/acrylonitrile copolymer and a monomeric compound wherein, after drying, the developed surface is in either order (1) postexposed to actinic radiation, and (2) contacted with 0.01 to 3.5% by weight aqueous bromine solution for about 15 seconds to 20 minutes.
    Type: Grant
    Filed: May 7, 1982
    Date of Patent: August 23, 1983
    Assignee: E. I. Du Pont de Nemours and Compamy
    Inventors: Michael G. Fickes, Bohdan Rakoczy
  • Patent number: 4400459
    Abstract: Process for providing improved solvent resistant surfaces of relief flexographic printing plates prepared by imagewise exposure and liquid development of the unexposed areas of a layer of a photosensitive elastomeric composition comprising a polymer of a conjugated diolefin hydrocarbon, and a monomeric compound wherein, after drying, the developed surface is in either order (1) postexposed to actinic radiation, and (2) contacted for about 15 seconds to 40 minutes with an aqueous treatment solution of an alkali monopersulfate, e.g., 2KHSO.sub.5.KHSO.sub.4.K.sub.2 SO.sub.4 and a bromide salt, e.g., potassium bromide.
    Type: Grant
    Filed: May 7, 1982
    Date of Patent: August 23, 1983
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Robert R. Gruetzmacher, Stanley H. Munger, Peter F. Warfield
  • Patent number: 4396703
    Abstract: A retouching agent for lithographic printing plate containing an admixture of (a) a lactone having 4 to 6 carbon atoms and (b) a glycol ether or ketone.
    Type: Grant
    Filed: January 18, 1982
    Date of Patent: August 2, 1983
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Hiroshi Matsumoto, Shizuo Miyano
  • Patent number: 4395479
    Abstract: Stripping compositions for removing resist materials from substrates comprise compositions of a 2-pyrrolidinone compound and a tetrahydrothiophene 1,1-dioxide compound. Either or both of polyethylene glycol and a diethylene glycol monoalkyl ether may be added to provide even more effective stripping compositions.
    Type: Grant
    Filed: August 17, 1982
    Date of Patent: July 26, 1983
    Assignee: J. T. Baker Chemical Company
    Inventors: Irl E. Ward, Lisa G. Hallquist, Thomas J. Hurley
  • Patent number: 4395480
    Abstract: The invention relates to a developer mixture for developing exposed, light-sensitive reproduction layers which contain a diazonium salt polycondensation product. The mixture comprises water, a salt of an alkanoic acid and a surfactant and contains 0.5 to 15 percent by weight, in particular 1 to 10 percent by weight, of at least one salt of an alkanoic acid having 8 to 13 carbon atoms and 0.5 to 20 percent by weight, in particular 1 to 12 percent by weight, of at least one low-foaming, nonionic surfactant. These surfactants preferably include optionally modified block polymers formed from ethylene oxide and propylene oxide.The invention also relates to a process for developing negative-working reproduction layers, of the composition indicated above, with the developer mixture according to the invention.
    Type: Grant
    Filed: January 6, 1982
    Date of Patent: July 26, 1983
    Assignee: Hoechst Aktiengesellschaft
    Inventor: Gerhard Sprintschnik
  • Patent number: 4393129
    Abstract: Stress and crack-free development of resist layers or films, for example composed of PMMA, used in production of galvanically generated flat precision parts is achieved. Resist layers having a thickness of at least 100 .mu.m are exposed via electron lithography or x-ray lithography techniques whereby very fine structure patterns having dimensions in the micron and sub-micron range are attained and developed with a developer comprised of a mixture of a material selected from the glycol ether group, a material selected from the primary amine group, a material selected from the aqueous group and a material selected from the azine group. Aspect ratios of 30:1 are achieved without dark errosion. Residual PMMA components remaining after development, as well as the developer itself, are fully removed with a post-development rinsing with water so that no disruptive layer residues remain on the surface which has been uncovered through development.
    Type: Grant
    Filed: September 17, 1981
    Date of Patent: July 12, 1983
    Assignee: Siemens Aktiengesellschaft
    Inventors: Walter Glashauser, Grigore-Vlad Ghica
  • Patent number: 4391897
    Abstract: Process for removing unexposed diazo from a silicated aluminum lithographic printing plate having a hydrophilic, anionic, negatively charged surface and a layer of a light sensitive, cationic diazo material which has been selectively exposed to actinic light in an image area. The plate is contacted after exposure with a solution of an anionic material in water. Anionic material from the solution ionically couples with unexposed diazo material and the solution still containing anionic material dissolves the coupled product from the unexposed areas producing a clean, hydrophilic background.
    Type: Grant
    Filed: June 17, 1981
    Date of Patent: July 5, 1983
    Assignee: Howard A. Fromson
    Inventors: Robert F. Gracia, Howard A. Fromson
  • Patent number: 4388391
    Abstract: Disclosed is a process for manufacturing a lithographic printing form by electrophotographic means, comprising the steps of uniformly charging an oleophilic photoconductive layer which is present on an electrically conductive hydrophilic layer support and which contains a photoconductor and a binder; image-wise exposing the charged photoconductive layer to produce a charge image; developing the charge image with toner to produce a toner image comprised of imaged areas and non-image areas; fixing the toner image; decoating the non-image areas of the photoconductive layer to bare the electrically conductive layer support; coating the bared areas of the layer support with a solution comprising a water-soluble, but hydrocarbon-insoluble film-forming polymer and a vinyl phosphonic acid compound; drying the coating solution to form a uniform coating; and removing the toner image by rinsing with a hydrocarbon composition containing aromatic portions in an amount of at least about 20% by weight.
    Type: Grant
    Filed: February 9, 1981
    Date of Patent: June 14, 1983
    Assignee: Hoechst Aktiengesellschaft
    Inventor: Loni Schell
  • Patent number: 4387152
    Abstract: A light-sensitive mixture is disclosed which contains a water-insoluble, aqueous-alkali-soluble binder, a light-sensitive o- or p-quinone-diazide or a mixture of (a) a compound which generates or splits off an acid on exposure to light and (b) a compound having at least one C--O--C group which can be cleaved by acid, and a phenol compound having 1 to 3 benzene nuclei which are mutually linked by single bonds, carbonyl groups, ether groups, thioether groups or optionally substituted methylene groups, and having at least one phenolic hydroxyl group and at least two substituents of the formula --CH.sub.2 OR, in which R is hydrogen or a lower alkyl or acyl group. The mixture is used for the preparation of light-sensitive copying material, preferably for the preparation of planographic printing forms. The addition of the phenolic compound has the effect that the developed printing forms can be baked at lower temperatures than hitherto in order to extend the printing run.
    Type: Grant
    Filed: October 20, 1981
    Date of Patent: June 7, 1983
    Assignee: Hoechst Aktiengesellschaft
    Inventor: Paul Stahlhofen
  • Patent number: 4383759
    Abstract: An apparatus and method is disclosed which will rapidly provide uniform layers of two liquid photopolymerizable materials for a capped (i.e., two layer) printing plate. The apparatus comprises a dual manifold which spans the plate-forming area of a surface and which is moved in tandem transversely in order to provide two overlapping layers of liquid photopolymerizable materials.
    Type: Grant
    Filed: November 25, 1981
    Date of Patent: May 17, 1983
    Assignee: Hercules Incorporated
    Inventors: William Bloothoofd, Norman E. Hughes
  • Patent number: 4381340
    Abstract: A developer suitable for machine and hand processing may now be made which accomplishes the aforementioned objects which is an aqueous solution comprising 2-propoxyethanol as a detackifying agent, an adjuvant solvent, a nonionic surfactant with a hydrophile-lipophile balance over about 17, and an inorganic salt. A developer/finisher may be prepared by adding thereto a water-soluble polymeric film former which is preferably polyvinyl pyrrolidone. A suspending agent, e.g. polyethylene glycol, is added to hand processing solutions.
    Type: Grant
    Filed: August 31, 1981
    Date of Patent: April 26, 1983
    Assignee: American Hoechst Corporation
    Inventor: John E. Walls
  • Patent number: 4379830
    Abstract: An improved aqueous alkaline developer for imagewise-exposed positive-acting photolithographic articles comprising a basic substance wherein the improvement comprises addition of a neutral salt of an alkali metal cation to the developer.
    Type: Grant
    Filed: October 6, 1981
    Date of Patent: April 12, 1983
    Assignee: Polychrome Corporation
    Inventors: Albert S. Deutsch, Christopher F. Lyons, Robert Piller
  • Patent number: 4374920
    Abstract: A developer composition for positive working lithographic printing plates and photoresists comprising an aqueous alkaline solution with a non-ionic surfactant.
    Type: Grant
    Filed: July 27, 1981
    Date of Patent: February 22, 1983
    Assignee: American Hoechst Corporation
    Inventors: Stanley F. Wanat, Shane Hsieh
  • Patent number: 4374036
    Abstract: A compositoin suitable for production of a fountain solution for lithographic printing operations, which comprises tetrapotassium pyrophosphate, monosodium phosphate, a sequestrant, a water-soluble polyethylene glycol, sodium carboxymethyl cellulose, a low- or non-foaming nonionic detergent, an anionic detergent and a polysiloxane. The invention is also directed to a concentrate and a fountain solution, both of which comprise a mixture of water and the foregoing composition.
    Type: Grant
    Filed: November 19, 1980
    Date of Patent: February 15, 1983
    Assignee: Michael A. Canale
    Inventors: Ralph D. Canale, Albert S. Canale, Harry Papazian
  • Patent number: 4371599
    Abstract: This invention relates to an improvement in the process for the preparation of printing forms and/or metallized images by electrostatic charging, exposing, and treating with a toner of a photoconductor layer applied to an electrically conductive support material, and removing the photoconductor layer in the non-image areas, the improvement which comprises effecting removal of the toner-free photoconductor layer by transferring it at a temperature in the range of about 50.degree. to 250.degree. C. to a receiving material which has a greater surface adhesion to the photoconductor layer than does the electrically conductive support material.
    Type: Grant
    Filed: December 14, 1976
    Date of Patent: February 1, 1983
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Erwin Lind, Ilse Bader
  • Patent number: 4370404
    Abstract: A novel desensitizing solution is disclosed which is applied to the surface of a lithographic printing plate coated with a photosensitive layer of a photopolymerizable composition, the desensitizing solution contains a hydrophilic colloid, a free radical polymerization inhibitor and water.
    Type: Grant
    Filed: November 5, 1981
    Date of Patent: January 25, 1983
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Hiromichi Tachikawa, Yohonosuke Takahashi, Kazuo Ishii, Tomoaki Ikeda, Fumiaki Shinozaki
  • Patent number: 4370406
    Abstract: A single-phase, non-emulsion water containing subtractive developer for lithographic plates having photopolymer coatings is provided. These developers include water and an active or primary solvent which is only partially soluble in water and which is a good solvent for the photopolymer of a lithographic plate that has not been exposed to and insolubilized by actinic radiation, this active solvent typically being present at a concentration near its water solubility limit. Preferably, a cosolvent is also included to increase the water solubility of the active solvent when necessary. A desensitizer may be included to impart to the formulation the properties of a one-step developer or of a finisher. Formulation and development methods for these developers are also included, and they may be used either as developers or as a machine developer solution replenisher.
    Type: Grant
    Filed: May 12, 1981
    Date of Patent: January 25, 1983
    Assignee: Richardson Graphics Company
    Inventor: Thomas H. Jones
  • Patent number: 4369239
    Abstract: Process for dot-etching a photopolymer layer no more than 0.015 mm thick and O.D. greater than 3.0 in the 350 to 400 nm region containing tone correctable image comprised of polymeric dots and lines having hardened upper skin which rests on softer undervolume having less degree of polymerization or hardening wherein a staging solution comprising a film forming hydrocarbon resin Mn of 500 to 3000 containing greater than 50% by weight aliphatic hydrocarbons, 25 to 50% by weight; aliphatic hydrocarbon solvent inert to photopolymer layer, 50 to 75% by weight, and optionally a dye or colorant and/or particulate material is applied to areas desired to protect; the solution is dried; the dot and line image is reduced by undercutting by mechanical action with a solvent of the softer undervolume and removing hardened polymer from the edges of the image; and the stage is removed by solvent therefor.
    Type: Grant
    Filed: August 3, 1981
    Date of Patent: January 18, 1983
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Bernard Feinberg, James W. O'Neil
  • Patent number: 4366224
    Abstract: A developer composition for positive photosensitive lithographic printing plates and photoresists comprising an aqueous solution of an inorganic lithium compound and sodium metasilicate.
    Type: Grant
    Filed: August 6, 1981
    Date of Patent: December 28, 1982
    Assignee: American Hoechst Corporation
    Inventor: Shane Hsieh
  • Patent number: 4361639
    Abstract: Surface treatment of lithographic printing plate which utilizes as ink receptive areas a photographically formed image silver per se or image silver halide per se is carried out in the presence of an organic compound having at least one mercapto or thione group and at least one hydrophilic group in the same molecule and an inorganic water-insoluble fine powder having a particle size of 0.1.mu. or less after imagewise exposure of a silver halide emulsion layer and processing thereof to develop an image, whereby ink receptivity, anti-staining property and printing endurance of the plate can be improved.
    Type: Grant
    Filed: July 22, 1981
    Date of Patent: November 30, 1982
    Assignee: Mitsubishi Paper Mills, Ltd.
    Inventors: Eiji Kanada, Toshiro Kondo, Shoji Yamada
  • Patent number: 4361642
    Abstract: Process for broadening the processing range of photohardenable negatively functioning reproduction materials wherein the unexposed areas are removed by liquid development and while still in contact with the developer the material is diffusely exposed to delayed actinic radiation, the delayed exposure amounting to at least 5% of the time necessary to clear the unexposed material.
    Type: Grant
    Filed: June 1, 1981
    Date of Patent: November 30, 1982
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Mario Grossa
  • Patent number: 4357416
    Abstract: An improved photosensitive litho element comprises, in order, a support, a non-photosensitive solvent-soluble contiguous layer having an optical density of at least 3.0 in the visible region of the spectrum and a maximum thickness of 0.015 mm, and a solvent-processable photosensitive layer. Dot-etchable contact litho negatives and positives are provided.
    Type: Grant
    Filed: August 26, 1981
    Date of Patent: November 2, 1982
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Roxy Fan