Product With At Least Two Named Layers Patents (Class 430/155)
  • Patent number: 4645730
    Abstract: The lithographic printing plate of the invention comprises a substrate having a hydrophilic surface, a coating on said surface of a light sensitive material (e.g., a water soluble diazo) and a top coating of discrete, oleophilic resin particles (e.g., an emulsion polymer), the resin particle coating being:(a) transparent to actinic light;(b) sufficiently permeable to allow a developer for the light sensitive material to penetrate through to the underlying light sensitive coating;(c) insoluble in said developer;(d) capable of being coalesced in situ after the plate is imaged and developed.
    Type: Grant
    Filed: September 17, 1984
    Date of Patent: February 24, 1987
    Assignee: Howard A. Fromson
    Inventors: Howard A. Fromson, Robert F. Cracia
  • Patent number: 4599295
    Abstract: Disclosed is a photosensitive material which has a first photosensitive layer formed on a support body such as an aluminum plate, a peel-off layer thereon and a second photosensitive layer formed on the peel-off layer in such a manner that the second layer can be photographically exposed to light and photographically developed independently from the first photosensitive layer and the first photosensitive layer may be subsequently photographically exposed with the picture image formed on the second photosensitive layer acting as a photographic mask. After the first photosensitive layer has been photographically developed, the two photosensitive layers may be used for different purposes, for instance, using the first photosensitive layer as a printing plate and the second photosensitive layer as a photographic film for making duplicate printing plates.
    Type: Grant
    Filed: September 14, 1983
    Date of Patent: July 8, 1986
    Assignee: Dainippon Screen Seizo K.K.
    Inventors: Syuzi Kondo, Akira Yamano, Keiji Toei
  • Patent number: 4578341
    Abstract: A relief image-forming composition having an acidic pH comprises a photosensitive component and an indicator capable of existing in two states differing in actinic opacity dependent upon pH. A relief image is formed by (1) exposing to light selected areas of a layer of the composition, the indicator being in its state of lower actinic opacity, (2) removing layer material from the exposed areas or from the unexposed areas and (3) shifting the pH in the remaining layer material to a value at which the indicator exists in its state of higher actinic opacity. The resultant image can then be used as an intermediate original in diazotype copying processes.
    Type: Grant
    Filed: August 3, 1984
    Date of Patent: March 25, 1986
    Assignee: Sensitisers (Research) Ltd.
    Inventors: Peter B. Readings, Nandor Mihalik, Robin Taylor
  • Patent number: 4557994
    Abstract: A light-sensitive printing plate is disclosed. The printing plate is comprised of a support base having a light-sensitive layer positioned thereon and a matting layer comprised of a micropattern of protuberances. The protuberances are present in a regular or randomly mixed manner on the light-sensitive layer and are comprised of a copolymer. The copolymer includes a monomer (unit a) with a sulfonic acid group, a monomer (unit b) selected from the group consisting of alkyl acrylates having 1 to 10 carbon atoms in the alkyl moiety thereof and alkyl methacrylates having 4 to 10 carbon atoms in the alkyl moiety thereof and a monomer (unit c) copolymerizable with monomer (unit a) and monomer (unit b), monomer (unit c) as a copolymer having a glass transition point of 60.degree. C. or above. The matting layer does not cause staining of a film original when superposed thereon and is resistant to rubbing or pressure and provides a surface which can be vacuum contacted with a film in a short period of time.
    Type: Grant
    Filed: September 13, 1984
    Date of Patent: December 10, 1985
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Teruo Nagano, Eiji Nakakita, Toshiyuki Sekiya
  • Patent number: 4547453
    Abstract: A layered sheet construction suitable after processing for use as a relief printing plate is provided. The sheet is made of a photosensitive layer comprising an elastomeric polymer, between about 5 and 30 phr of an ethylencially unsaturated compound and between 0.1 and 5 phr of a photoinitiator activatable by actinic radiation; a base layer immediately adjacent to said photosensitive layer capable of supporting a relief image after processing; having the same or a different composition than said photosensitive layer. The sheet is bonded to an open or closed cell foam layer having a thickness between about 0.010 inch and 0.250 inch. Said foam has a recovery rate of at least 80%, a compression value between about 0.003 inch and 0.030 inch and a density of between about 2 to 50 lbs/ft.sup.3 and is bonded to a dimensionally stable supporting layer.
    Type: Grant
    Filed: November 21, 1983
    Date of Patent: October 15, 1985
    Assignee: Uniroyal, Inc.
    Inventors: John R. Worns, James W. Chase, Bruce W. Capriotti
  • Patent number: 4544619
    Abstract: This invention relates to a light sensitive laminate comprising a light sensitive layer of photoresist, a support therefor, and an intermediate protective layer preferably of a light transmitting material disposed between said photoresist layer and said support. In use, the photoresist layer of the laminate is adhered to a base material and the support stripped therefrom, thereby leaving a composite comprising the base material, photoresist layer and intermediate protective layer disposed over said photoresist layer. The intermediate layer serves to protect the photoresist layer from damage such as by abrasion or otherwise during processing, thereby permitting storage of the so-formed composite prior to use. Since the intermediate layer may be of a light transmitting material, photoimaging may take place through the intermediate layer with the intermediate layer subsequently removed by contact with a solvent that is a non-solvent for those areas of photoresist left after development.
    Type: Grant
    Filed: February 29, 1984
    Date of Patent: October 1, 1985
    Assignee: Shipley Company Inc.
    Inventors: Carl W. Christensen, Calvin Isaacson
  • Patent number: 4530896
    Abstract: This invention relates to a light-sensitive laminate comprising a light-sensitive layer of photoresist, a support therefor, and an intermediate protective layer preferably of a light-transmitting material disposed between said photoresist layer and said support. In use, the photoresist layer of the laminate is adhered to a base material and the support stripped therefrom, thereby leaving a composite comprising the base material, photoresist layer and intermediate protective layer disposed over said photoresist layer. The intermediate layer serves to protect the photoresist layer from damage such as by abrasion or otherwise during processing, thereby permitting storage of the so-formed composite prior to use. Since the intermediate layer may be of a light-transmitting material, photo-imaging may take place through the intermediate layer with the intermediate layer subsequently removed by contact with a solvent that is a non-solvent for those areas of photoresist left after development.
    Type: Grant
    Filed: May 16, 1972
    Date of Patent: July 23, 1985
    Assignee: Shipley Company Inc.
    Inventors: Carl W. Christensen, Calvin Isaacson
  • Patent number: 4522910
    Abstract: A novel photosensitive film structure comprises a generally continuous minor phase material and a generally discontinuous major phase material. The minor phase includes a photosensitive compound whose solubility relative to a selected solvent changes upon exposure to electrromagnetic radiation, while the major phase is not photosensitive nor soluble in the solvent. The two phases are uniformly interdispersed throughout the film structure. Imagewise exposure to electromagnetic radiation renders the film structure selectively permeable to the selected solvent, and, after development, the film structure exhibits the chemical and physical properties of the major phase material. The film structure finds varied application in the manufacture of graphic arts articles such as lithographi printing plates and photoresists.
    Type: Grant
    Filed: November 18, 1982
    Date of Patent: June 11, 1985
    Assignee: Napp Systems (USA), Inc.
    Inventor: Robert W. Hallman
  • Patent number: 4501810
    Abstract: The lithographic printing plate of the invention comprises a substrate having a hydrophilic surface, a coating on said surface of a light sensitive material (e.g., a water soluble diazo) and a top coating of discrete, oleophilic resin particles (e.g., an emulsion polymer), the resin particle coating being:(a) transparent to actinic light;(b) sufficiently permeable to allow a developer for the light sensitive material to penetrate through to the underlying light sensitive coating;(c) insoluble in said developer;(d) capable of being coalesced in situ after the plate is imaged and developed.
    Type: Grant
    Filed: March 3, 1983
    Date of Patent: February 26, 1985
    Assignee: Howard A. Fromson
    Inventors: Howard A. Fromson, Robert F. Gracia
  • Patent number: 4472494
    Abstract: Bilayer photosensitive imaging articles comprising a substrate coated with an image layer and a resist layer are disclosed. The substrate may be transparent, translucent or opaque to give imaging articles useful in different applications. The image layer which should be from about 0.3-3.0 microns in thickness includes an organic film-forming vehicle from the group of copolymers of the formula: ##STR1## where P is styrene, ethylene or methyl vinyl ether; m is 1-3; n is 1,10; X is OH, OHN.sub.2, ONH.sub.4, OR, ONH.sub.3 R, ONH.sub.2 R.sub.2, ONHR.sub.3, ONH.sub.3 RNH.sub.2, ONa, OK, OLi; R is an alkyl group in the range C.sub.1 -C.sub.10 optionally including a functional group such as ketone, alcohol, esther, ether alcohol or aryl; m=1-3, n=1-10; and the molecular weight is between 1,000-150,000. The image layer may also include a coloring medium. The resist layer, which should be from about 0.5 to about 2.
    Type: Grant
    Filed: July 6, 1982
    Date of Patent: September 18, 1984
    Assignee: Napp Systems (USA), Inc.
    Inventors: Robert W. Hallman, Eugene L. Langlais, Ronald G. Bohannon, Dominic B. Rubic
  • Patent number: 4452876
    Abstract: The invention concerns a heat, steam or water developing diazotype material, containing a photosensitive diazonium salt stabilized with a non-diffusing acid and also one or several developing coats--which could contain the coupling agent--located on the front or back side of the used base material, products avoiding the interpenetration of the active agents, preventing the washing of one coat through the another during coating process, slowing down the absorption of ambient humidity at normal temperature, absorbing the volatile alkaline products at normal temperature, separating the essential reagents to avoid their spontaneous reaction, releasing an accelerating plasticizer during the development, reducing the activation temperature, improving the development by formation of an insoluble salt with the stabilizing acid, releasing a non-volatile weak acid in case of an attack by moisture.
    Type: Grant
    Filed: May 19, 1981
    Date of Patent: June 5, 1984
    Inventors: Andre Schaeffer, Antoine Wagner
  • Patent number: 4421839
    Abstract: A heat-sensitive recording sheet is proposed which has a heat-sensitive recording layer laminated on one surface of a support body and containing a diasosulfonate; a acid coupling agent comprising a compound having aromatic ring, hetroaromatic ring or substituted aromatic ring bonded thereto OH group and COOH group; and a thermoplastic resin having a glass transition point of 70.degree.-150.degree. C. or a photocuring resin.
    Type: Grant
    Filed: March 3, 1982
    Date of Patent: December 20, 1983
    Assignees: Dai Nippon Printing Co., Ltd., Tokyo Shibaura Denki Kabushiki Kaisha
    Inventors: Ryohei Takiguchi, Masayoshi Nagashima
  • Patent number: 4418112
    Abstract: A composite film comprising a first layer comprising a polyolefin resin containing finely divided calcium carbonate dispersed therein and a surface layer comprising a polyolefin resin containing an acidic filler dispersed therein, which surface layer is bonded directly or indirectly to at least one surface of the first layer and has a thickness of at least 3 microns. A diazo copying paper is also disclosed which has a photosensitive diazo layer on the surface layer of the composite film.
    Type: Grant
    Filed: September 9, 1981
    Date of Patent: November 29, 1983
    Assignee: Oji Yuka Goseishi Kabushiki Kaisha
    Inventors: Takashi Toyoda, Yozo Ohba, Masaaki Yamanaka
  • Patent number: 4414311
    Abstract: Light sensitive compounds are deposited onto a hydrophilized metal substrate, which is preferably aluminum, by means of a direct current electromotive force. The light sensitive component is dissolved in a current carrying solvent. Cathodic, hydrophilized, aluminum is passed through the solution and the EMF applied. The result is a light sensitive coating on the hydrophilized substrate surface.
    Type: Grant
    Filed: March 18, 1982
    Date of Patent: November 8, 1983
    Assignee: American Hoechst Corporation
    Inventors: John E. Walls, Thomas A. Dunder
  • Patent number: 4410620
    Abstract: The present invention relates to new offset plates wherein the surface of the steel-containing support is coated with a thin water-accepting layer of chromium and chromium oxide.
    Type: Grant
    Filed: April 10, 1981
    Date of Patent: October 18, 1983
    Inventor: Jean-Marie Nouel
  • Patent number: 4388399
    Abstract: A light-sensitive image-forming material which comprises a support having provided thereon a first layer comprising at least one alcohol-soluble polyamide resin and, on said first layer, a second layer comprising a light-sensitive photoresist composition, said layer containing said alcohol-soluble polyamide resin containing one or more polymers having one or more of a free carboxy group(s), one or more of a phenolic hydroxy group(s) or a maleic anhydride group in a proportion of about 0.1:9.9 to 6:4 by weight to said polyamide resin.
    Type: Grant
    Filed: February 10, 1982
    Date of Patent: June 14, 1983
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Fumiaki Shinozaki, Tomizo Namiki, Tomoaki Ikeda
  • Patent number: 4386145
    Abstract: In the forming of microcellular arrays, such as those useful in photography, a closure is positioned to overlie a plurality of microcells forming a planar array. The closure is selectively removed from one set of micro- cells forming an interlaid pattern with a second set of microcells so that the contents of the first set of micro- cells can be changed without concurrently changing the contents of the second set of microcells.
    Type: Grant
    Filed: May 6, 1982
    Date of Patent: May 31, 1983
    Assignee: Eastman Kodak Company
    Inventor: Hugh S. A. Gilmour
  • Patent number: 4339520
    Abstract: A light-sensitive vesicular recording material comprising a support and a layer comprised of a binder and a light-sensitive compound applied to the support, said binder comprising a butanone soluble copolymer of methacrylonitrile and vinylidene chloride; particularly, a mixture of a butanone soluble methacrylonitrile/vinylidene chloride copolymer and a vinylidene chloride/acrylonitrile copolymer, said copolymers being miscible with each other in butanone.
    Type: Grant
    Filed: March 31, 1981
    Date of Patent: July 13, 1982
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Markus Seibel, Bernd Huber, Irmgard Bindrum, Dieter Bodenheimer
  • Patent number: 4334003
    Abstract: Presensitized lithographic plates having a diazo layer are prepared such that they exhibit a photospeed rendering them suitable for ultra high speed operations including use within laser platemaking systems. These ultra high speed plates have a diazo layer that is exceedingly thin while still being generally uniformly distributed throughout the plate area. The process includes extracting a significant quantity of diazonium compound or diazonium resin from a diazo layer on a presensitized plate substrate. Plates thus formed are useful in laser exposures for facsimile transmissions, as projection plates, as camera back plates, for step and repeat plate work, and where low intensity light sources are used in conjunction with very large plates.
    Type: Grant
    Filed: September 18, 1980
    Date of Patent: June 8, 1982
    Assignee: Richardson Graphics Company
    Inventor: Thomas H. Jones
  • Patent number: 4326020
    Abstract: Described is a lithographic element which may optionally be used as a positive working or a negative working element by minor changes in exposure and development parameters.
    Type: Grant
    Filed: September 10, 1980
    Date of Patent: April 20, 1982
    Assignee: Polychrome Corporation
    Inventors: Eugene Golda, Alan Wilkes
  • Patent number: 4314019
    Abstract: A radiation-sensitive element is disclosed including a radiation-sensitive layer comprised of a cobalt(III)complex and a photoreductant. A process is disclosed in which the photoreductant is converted to a reducing agent by exposure to electromagnetic radiation longer than 300 nanometers. The reducing agent is then reacted with a cobalt(III)complex. Images can be recorded directly within the radiation-sensitive layer or in a separate image-recording element or layer by use of the residual cobalt(III)complex not exposed or one or more of the reaction products produced by exposure. By using the ammonia liberated from ammine ligand containing cobalt(III)complexes on exposure in combination with imagewise and uniform exposures, positive or negative images can be formed in diazo image-recording layers or elements associated with the radiation-sensitive layer. By the selection of amine-responsive reducing agent precursors, the amines released by the cobalt(III)complexes cause an amplified image.
    Type: Grant
    Filed: August 2, 1979
    Date of Patent: February 2, 1982
    Assignee: Eastman Kodak Company
    Inventors: Anthony Adin, James C. Fleming
  • Patent number: 4307172
    Abstract: Disclosed is an imaging light-sensitive material which comprises a transparent substrate, [I] a polyamide layer containing an alcohol-soluble polyamide as the major component and having a thickness of from 2 to 11 microns and [II] a light-sensitive layer having a thickness of from 0.5 to 5 microns.
    Type: Grant
    Filed: April 30, 1980
    Date of Patent: December 22, 1981
    Assignee: Daicel Chemical Industries, Ltd.
    Inventors: Tetsuo Ishihara, Keizi Kubo
  • Patent number: 4302524
    Abstract: A light-sensitive vesicular imaging composition comprising a vesiculating agent which liberates gas upon exposure to activating radiation and a matrix which is a novolac branched epoxy resin of a bis-glycidyl ether and a dihydric phenol.
    Type: Grant
    Filed: March 19, 1980
    Date of Patent: November 24, 1981
    Assignee: GAF Corporation
    Inventors: William L. Mandella, James R. Kuszewski
  • Patent number: 4301229
    Abstract: A support for a lithographic plate comprising an aluminum plate or an aluminum-alloy plate the surface of which has been grained such that the grain structure comprises pits and;(i) the distribution of pit diameter is such that the pits corresponding to 5% and 95% on a cumulative frequency curve for pit diameter are about 3.mu. or more and about 10.+-.1.mu. in diameter, respectively; and(ii) the center line average roughness (Ra) of said surface is on the range from about 0.6 to 1.0.mu.. A light-sensitive material for preparing a lithographic plate is also disclosed.
    Type: Grant
    Filed: March 27, 1979
    Date of Patent: November 17, 1981
    Assignees: Fuji Photo Film Co., Ltd., Nippon Light Metal Co., Ltd.
    Inventors: Hirokazu Sakaki, Akira Shirai, Azusa Ohashi
  • Patent number: 4292389
    Abstract: There is provided a process for preparing a photosensitive plate for printing which comprises providing a heat-depositable fine powder having a constant directional size of 0.5-40.mu. onto the surface of a photosensitive plate for printing at a ratio of 0.005-0.5 g. of the said powder per m.sup.2 of the said plate to uniformly disperse and adhere the said powder onto the said surface, while preheating the right side (side on which powder adheres) and/or the reverse side of the said plate upon providing said powder or before or after providing, and subsequently contacting the right side of the said plate with a heating roll having a high releasing surface, whereby the said fine powder is fused and fixed on onto the surface of the said plate.
    Type: Grant
    Filed: January 24, 1980
    Date of Patent: September 29, 1981
    Assignee: Konishiroku Photo Industry Co., Ltd.
    Inventors: Hiroshi Kojima, Kunio Ito, Masami Akiyama, Takeshi Tanaka
  • Patent number: 4288521
    Abstract: There is provided a process for the production of a photosensitive plate for printing which comprises providing a given amount of a fine powder having a constant directional size of 0.5-40 .mu. from a dust supplier directly or via a distributor to a cyclone, feeding the said powder together with a small volume of air from the bottom of said cyclone, uniformly dispersing and adhering the so flowed fine powder onto the surface of a continuously running photosensitive plate for printing.
    Type: Grant
    Filed: January 24, 1980
    Date of Patent: September 8, 1981
    Assignee: Konishiroku Photo Industry Co., Ltd.
    Inventors: Hiroshi Kojima, Kunio Ito, Masami Akiyama, Takeshi Tanaka
  • Patent number: 4284704
    Abstract: Imaging means, such as a tetrazolium salt, capable of reduction to form a visible image is present in a radiation-sensitive layer in combination with a photoreductant incorporating one or more labile hydrogen atoms and capable of producing a reducing agent precursor in radiation-struck areas of the layer. An image is produced in the layer by processing the layer after imagewise exposure to actinic radiation.
    Type: Grant
    Filed: September 29, 1978
    Date of Patent: August 18, 1981
    Assignee: Eastman Kodak Company
    Inventors: James C. Fleming, Joseph W. Manthey, Ralph T. Brongo
  • Patent number: 4283477
    Abstract: In a photothermographic element comprising (A) at least one photosensitive layer comprising a photosensitive component, such as photosensitive silver halide or a diazotype photosensitive material, (B) at least one layer comprising a processing agent for the photosensitive component and (C) a separation polymer between (A) and (B), increased preexposure storage stability is provided by a polysulfonamide as separation polymer (C). After imagewise exposure of the photothermographic element, an image can be developed by merely heating the element to moderately elevated temperatures.
    Type: Grant
    Filed: November 2, 1978
    Date of Patent: August 11, 1981
    Assignee: Eastman Kodak Company
    Inventors: George L. Fletcher, Jr., Richard A. deMauriac, Stewart H. Merrill
  • Patent number: 4272603
    Abstract: A vesicular photographic material comprising a polymeric matrix containing a sensitizer which liberates gas when exposed to light, and a process for manufacture of said material. The polymeric matrix comprises a blend of polymethacrylonitrile homopolymer with another resin selected from the group consisting of vinyl polymers and copolymers; epoxy polymers; and copolymers with polyurethane segments. Improved photometrics, particularly film speed, are realized.
    Type: Grant
    Filed: November 6, 1979
    Date of Patent: June 9, 1981
    Inventors: Donald J. Chenevert, John R. Grawe, John C. McDaniel
  • Patent number: 4268600
    Abstract: A photochemical color-printing process for textile articles wherein a photosensitive triazene and azo dye coupling agent are applied to surface of textile article, the coated textile is exposed to light with a negative image, unreacted chemical products are removed by washing and rinsing the coated textile article after imaging, and then the coated textile article is dried.
    Type: Grant
    Filed: December 1, 1978
    Date of Patent: May 19, 1981
    Assignee: Issec and Tissages de Soieries Rennis
    Inventors: Jean J. Robillard, Claude R. Riou
  • Patent number: 4232105
    Abstract: A photosensitive lithographic printing plate having an excellent printing durability, which comprises a supporting layer, a hydrophilic layer formed on the supporting layer, a photosensitive layer formed on the hydrophilic layer surface and, optionally, a water-proof layer located between the supporting layer and the hydrophilic layer, the photosensitive layer being composed of a photosensitive diazo resin modified by a phenol compound and a water-soluble acrylic polymer compound, and the hydrophilic layer being composed of a resinous component comprising 5 to 40% by weight of a urea compound resin and 60 to 95% by weight of a polyamide resin, and a pigment component.
    Type: Grant
    Filed: November 21, 1978
    Date of Patent: November 4, 1980
    Assignee: Oji Paper Co., Ltd.
    Inventors: Hideaki Shinohara, Masaru Kato, Yoshiaki Takamatsu
  • Patent number: 4215191
    Abstract: Vesicular recording materials include a sensitized layer which comprises a polymeric vehicle for the sensitizing agent which is a copolymer of 62 to 95 mole % of acrylonitrile or a derivative thereof with acrylamide or a derivative thereof. Preferred copolymers are derived from acrylonitrile and N-tert.butyl acrylamide or diacetone acrylamide. The sensitized layers may contain a surfactant and may be subjected to water treatment.
    Type: Grant
    Filed: February 5, 1979
    Date of Patent: July 29, 1980
    Assignee: Bexford Limited
    Inventor: John C. Kwok
  • Patent number: 4207108
    Abstract: Improved photographic speed is provided in a photothermographic material comprising in reactive association (a) photosensitive silver halide, (b) an oxidation-reduction image-forming combination comprising (i) a long-chain fatty acid silver salt oxidizing agent, with (ii) a reducing agent, (c) a synthetic polymeric binder, and (d) a photographic speed increasing concentration of a certain non-dye, thione speed increasing addendum. A developed image having increased photographic speed can be provided in the described photographic material, after imagewise exposure, by heating the element to moderately elevated temperatures.
    Type: Grant
    Filed: February 13, 1978
    Date of Patent: June 10, 1980
    Assignee: Eastman Kodak Company
    Inventor: Gary L. Hiller
  • Patent number: 4198470
    Abstract: A base plate adapted to be coated with a light-sensitive diazo resin, and a lithographic plate which may be prepared therefrom. The base plate includes a substrate comprising a metal support and having a water-wettable, hydrophilic surface. Over the substrate and in direct contact with the surface is a layer comprising an oleophilic ink-receptive organic resin adapted to receive a light-sensitive coating comprising a diazo resin sensitizer. The oleophilic resin layer is permeable to the sensitizer so that it may penetrate substantially through the resin layer to establish sufficient contiguity between the diazo resin and the substrate so that both the light-sensitive coating and the organic resin layer become anchored to the substrate in the areas of exposure when the light-sensitive coating is exposed to light. Methods of preparing the base plate and lighographic plate are also disclosed.
    Type: Grant
    Filed: March 7, 1978
    Date of Patent: April 15, 1980
    Assignee: Western Litho Plate & Supply Co.
    Inventors: Jim D. Meador, Edward H. Parker