Abstract: A lithographic coating and method of framing a lithographic image are disclosed. The method comprises coating at least a portion of a surface of an article with a radiation-crosslinkable polymer, and exposing the coated surface to a pattern of radiation to crosslink the polymer in a lithographic image. The functionalized polymer is a copolymer of an isoolefin of 4 to 7 carbon atoms and para-alkylstyrene, wherein the para-alkylstyrene is functionalized with a radiation reactive group at the para-alkyl group of the para-alkylstyrene.

Abstract: A photosensitive lithographic printing plate which provides a wide range of proper conditions for development, high impression capacity, a flexible film sufficient in adhesion to a support and excellent processing suitability with a weakly alkaline developer (pH 12.5 or less) is disclosed. The photosensitive lithographic printing plate comprises a support and a photosensitive layer provided thereon, wherein the photosensitive layer is formed from a photosensitive composition containing at least a two-equivalent coupler residue-containing compound and a photosensitive compound or a photosensitive mixture acting as a positive type.

Abstract: For producing fine printing patterns on large serigraphical printing frames it is possible to apply an exposure through correspondingly large film areas, but it is cheaper to make use of a successive line-by-line exposure with the use of a modulated light or laser beam, which is caused to sweep across an emulsion coated printing frame surface from an oscillating deflection mirror. The beam (20), in its outermost positions, will be directed obliquely towards the surface (14), and if the latter changes its distance from the oscillating mirror (48) the exposure lines (16) will thus be correspondingly shorter or longer, whereby the printing pattern may be distorted.

Abstract: The present invention relates to a thermosensitive lithographic printing original plate comprising a substrate, a hydrophilic layer containing a hydrophilic binder polymer, and a microcapsuled oleophilic material which forms an image area by heating; the hydrophilic binder polymer having a three-dimensional cross-link and a functional group which chemically combines with the oleophilic material in the microcapsule when the microcapsule is decomposed, and the microcapsuled oleophilic material having a functional group which chemically combines with the hydrophilic binder polymer when the microcapsule is decomposed.The thermosensitive lithographic printing original plate of the present invention is excellent in printing durability and storage property and provides prints having clear images because the plate does not collect scumming. Further, development is not required in the platemaking process so that there are no problems with waste treatment and the like.

Abstract: A method used in offset printing utilizes an electrically encoded image, stored in an electronic memory, to be transferred to a printing substrate during a coating application in an offset printing process. An offset printing blanket is attached under tension to a blanket cylinder of an offset printing machine. After attachment of the blanket to the cylinder, the blanket is automatically cut in accordance with the electrically encoded image. Subsequently, sections of the blanket are removed along cut lines made in the outer layer during the cutting thereof.

Abstract: A method for producing a press-ready lithographic printing plate which comprises:(A) providing an uncoated lithographic substrate;(B) coating a photosensitive layer on one side of the lithographic substrate;(C) providing a flexible substrate;(D) coating an adhesive layer directly on the flexible substrate;(E) laminating the coated lithographic substrate to the coated flexible substrate;(F) imagewise exposing the laminated element of (E) to radiation to which the photosensitive layer is sensitive; and(G) peeling off the flexible substrate along with the nonimage areas of the photosensitive layer, leaving the press-ready image areas of the colored photosensitive layer and the adhesive layer on the lithographic substrate.

Abstract: A process for recycling exposed and/or unexposed photopolymer flexographic printing plate containing a photopolymerizable recording layer and a support, said process comprising (a) separating the recording layer from the support and comminuting the material and (b) adding the material to a photopolymer mixture is described. The process reduces waste problems, is more environmentally friendly and is used to prepare photopolymerizable flexographic printing plates containing less raw materials.

Abstract: Hydroxylamine, alkanolamine, and ammonium phthalamate compounds are useful as contrast enhancers when used in combination with (i) hindered phenol developers, and (ii) trityl hydrazide and/or formyl-phenyl hydrazine co-developers, to produce ultra-high contrast black-and-white photothermographic and thermographic elements.The photothermographic and thermographic elements may be used as a photomask in a process where there is a subsequent exposure of an ultraviolet or short wavelength visible radiation-sensitive imageable medium.

Abstract: Acrylonitrile compounds are useful as co-developers when used in combination with hindered phenol developers to produce high contrast black-and-white photothermographic and thermographic elements.Acrylonitrile compounds are also useful as co-developers when used in combination with (i) hindered phenol developers, and (ii) trityl hydrazide and/or formyl-phenyl hydrazinc co-developers, to produce ultra-high contrast black-and-white photothermographic and thermographic elements.The photothermographic and thermographic elements may be used as a photomask in a process where there is a subsequent exposure of an ultraviolet or short wavelength visible radiation-sensitive imageable medium.

Abstract: Hydroxamic acid compounds are useful as contrast enhancers when used in combination with (i) hindered phenol developers, and (ii) trityl hydrazide and/or formyl-phenyl hydrazine co-developers, to produce ultra-high contrast black-and-white photothermographic and thermographic elements.The photothermographic and thermographic elements may be used as a photomask in a process where there is a subsequent exposure of an ultraviolet or short wavelength visible radiation-sensitive imageable medium.

Abstract: Heat-developable silver-based photosensitive imaging element comprising a heat-reducible organic silver salt, a photosensitive silver halide, a developing agent, and a releasing compound that upon reaction with either the reduced or the oxidized form of the developing agent is capable of releasing a hydrophobizing agent. The invention also relates to a method for producing a lithographic printing plate comprising image-wise exposing an imaging element, bringing the exposed element in face-to-face contact with an oleophobic surface of a printing plate precursor, heating the imaging element while in contact or before being brought in contact with the oleophobic surface to cause reduction of the organic silver salt and to cause the release of the hydrophobizing agent from the releasing compound, allowing the hydrophobizing agent to diffuse to the oleophobic surface to render the surface image-wise oleophilic, and separating the resulting lithographic printing plate from the imaging element.

Abstract: Trityl hydrazides and formyl-phenyl hydrazines are useful as co-developers with hindered phenols in phothothermographic and thermographic elements. These co-developers have the formula:R.sup.1 --(C.dbd.O).sub.n --NHNH--R.sup.2R.sup.1 represents hydrogen and R.sup.2 represents an aryl or substituted aryl group; or,R.sup.1 represents hydrogen, alkyl and alkenyl groups of up to 20 carbon atoms; alkoxy, thioalkoxy, or amido groups of up to 20 carbon atoms; aryl, alkaryl, or aralkyl groups of up to 20 carbon atoms; aryloxy, thioaryloxy, or anilino groups of up to 20 carbon atoms; aliphatic or aromatic heterocyclic ring groups containing up to 6 ring atoms; carbocyclic ring groups comprising up to 6 ring carbon atoms; or fused ring or bridging groups comprising up to 14 ring atoms; and R.sup.2 represents a trityl group.

Abstract: Sulfonyl hydrazides are used as developers in phothothermographic and thermographic elements. The sulfonyl hydrazides have the formula:R.sup.1 --CO--NHNH--SO.sub.2 --R.sup.2wherein R.sup.1 and R.sup.

Abstract: In a method of producing master and working pattern plates for etching to form a shadow mask, various etching patterns are needed, for example, a pattern of predetermined holes for passing electron beams, a pattern of register marks necessary for accurate alignment of a pair of obverse and reverse working pattern plates, and a frame pattern for cutting off a portion which is to be a shadow mask from a metal plate by etching process. These individual pattern data required for etching are first prepared and then subjected to logical operation to prepare data representative of a synthetic pattern which is to be finally drawn on a photosensitive plate. Then, all the necessary patterns, including the frame pattern, register mark pattern, hole pattern, etc.

Abstract: A simplified process for making plates used in printing, including forming a chemically positive copy on a transparent or translucent sheet-like structure with the lines thereon being constituted of artificial powder without going through the steps of photographing and contact copying. The copy so formed may be directly used in retouching and then plate processing. This process does not require the use of photosensitive films and chemical photograhing so that the speed of making plates is increased and damage to the environment decreased.

Abstract: Positive photoresist compositions comprising, in an organic solvent, at leasta) one alkali-soluble resin,b) one photosensitive quinone diazide,c) one aromatic hydroxy compound of formula I ##STR1## wherein each R is --H, C.sub.1 -C.sub.4 alkyl, C.sub.1 -C.sub.4 alkoxy, --OCH.sub.2 C.sub.6 H.sub.5, --OC.sub.6 H.sub.5 or --COOC.sub.1 -C.sub.4 alkyl, and R.sub.1 and R.sub.2 are each independently of the other H, C.sub.1 -C.sub.4 alkyl, --C.sub.6 H.sub.5 or a cycloaliphatic 5- or 6-membered ring, a is an integer from 0 to 4, and m and n are each independently of the other 0, 1 or 2, which compound enhances the photosensitivity and/or the rate of development, and optionallyd) additional customary modifiers, are eminently suitable for making relief structures.

Abstract: Disclosed is a method of making a subtractive offset printing plate, in which a subtractive offset printing plate containing at least a composite diazo photo sensitive material and a hydroxyl group-having acrylic copolymer in the photosensitive layer is imagewise exposed and the thus imagewise-exposed printing plate is automatically conveyed and developed with a developer with applying (a) developing brush(es) under pressure to the moving printing plate in the presence of the developer, the brush(es) being rotated around the axis vertical to the surface of the printing plate and being moved by reciprocating motion to the direction perpendicular to the moving direction of the printing plate and along the axis parallel to the surface of the printing plate. By the method, a good printing plate may be made, using a popular automatic additive developing machine of a particular system to which a subtractive developer involving few environmental problems is applied.

Abstract: A photocurable gel suitable for articles such as printing plates, photoresists and the like is disclosed. The photocurable eel comprises (a) a polymer composition having isotactic polymethyl methacrylate moiety; and syndiotactic polymethyl methacrylate moiety; (b) a photopolymerizable ethylenically unsaturated compound; and (c) a photopolymerization initiator. The gel is solid at ambient temperature and is capable of undergoing reversible gel/sol transition by heating or cooling. Methods of preparing articles, as well as methods of fixing articles, which use the gel are also disclosed. Such methods include sealing or affixing component parts on an electronic circuit board.

Abstract: A photosensitive element comprising (a) a support, (b) a thermally hardened layer containing the reaction product of (i) either an organic polymer having reactive segments and nonreactive segments or a blend of organic polymers wherein at least one polymer has reactive segments and at least one polymer has nonreactive segments (ii) a crosslinking agent and (iii) a catalyst and (c) a photohardenable layer is described.

Abstract: The method which comprises the steps of producing a halftone dot photograph, producing a cut out photograph by cutting out a desired portion of the photograph, adhering the cut out photograph on a transparent film, printing the front side of this film on a positive film to produce a halftone positive film, printing the backside of said film on a negative film to produce a silhouette film in which the cut out portion appears as deep-black, superposing the halftone positive film on a photosensitive resin plate to produce a photographic resin plate, turning the silhouette film upside down and superposing it on the photosensitive resin plate and exposing it to light to produce a silhouette resin plate, alternately bringing the photographic resin plate and silhouette resin plate into contact with a continuous foaming resin plate.

Abstract: Photocurable elements which are useful for preparing flexographic printing plates are provided which comprise a printing layer and a contiguous base layer, the printing layer comprising about 40 to 95 parts by weight of an elastomeric block copolymer, about 5 to 60 parts by weight of a second elastomeric polymer which is incompatible with the block copolymer, a photopolymerizable monomer, and a photoinitiator. The printing layer preferably also comprises an actinic radiation scattering and absorbing pigment.Also provided are relief printing plates prepared from the photocurable elements. The printing plates have a tack-free surface having excellent ink transfer properties, abrasion resistance, and solvent resistance. A high level of exposure latitude may also be provided in the photocurable elements of the invention.

Abstract: Prevention of printing stains occurring on positions corresponding to the end parts of the printing plate in the case of printing on a rolled paper by a rotary press machine, as in newspaper printing can be accomplished by a process for the production of a lithographic printing plate, which comprises subjecting a lithographic printing plate transported in a predetermined direction by a transporting means to a beveling treatment of end parts thereof and then subjecting the beveled parts to a treatment for rendering hydrophilic.

Abstract: A photopolymer useful in preparing water-developable, solid printing plates is prepared by preparing a urethane prepolymer by reacting polyoxyalkylene diols or polyester diols, or a mixture thereof, with an excess of diisocyanate, followed by chain extending the resulting prepolymer mixture with an alkyldialkanolamine, then reacting the chain-extended product with a hydroxyalkyl(meth)acrylate. The resulting photopolymer is suitably formulated with additional photoactive (meth)acrylate monomers or oligomers and photoinitiator for casting or extrusion on a substrate to form a flexographic printing plate. Following UV exposure of the plate through a negative, unexposed areas can be removed by washing with a slightly acidic aqueous medium, to give a plate with a desirable relief image. The use of the aqueous washout solution as opposed to organic solvents minimizes pollution problems.

Abstract: An X-Ray sensitive composition including one or several photopolymerizable monomer or photocrosslinkable polymer systems and thermochromic substances which can be used in a dry X-Ray reproduction process. The process is based on the different dielectric constants and dielectric losses exhibited by a monomer and the corresponding polymer or a polymer and the crosslinked polymer and the reaction of certain thermochromic substances which exhibits a specific threshold temperature above which these substances change from a colorless form to a color stable form. The X-Ray sensitive element is exposed according to a pattern of X-Ray with spatial modulation providing an X-Ray image to form a latent image of polymerized or crosslinked zones and unpolymerized or non crosslinked zones.

Abstract: A photocurable composition useful in preparing water-developable, solid printing plates is prepared by blending a urethane (meth)acrylate prepolymer with a complexing polymer based on poly(vinyl pyrrolidone) composition. The resulting composition is suitably formulated with additional photoactive (meth)acrylate monomers or oligomers and photoinitiator for casting or extrusion on a substrate to form a flexographic printing plate. Following UV exposure of the plate through a negative, unexposed areas can be removed by washing with aqueous media, to give a plate with a desirable relief image. The use of the aqueous washout solution as opposed to organic solvents minimizes pollution problems. The use of the complexing polymer significantly reduces the cold flow of the uncured plate and both increases toughness and reduces tack of the cured plate.

Abstract: A photosensitive printing medium is compounded from a latex copolymer, a linear thermoplastic, elastomeric block copolymer, a basic nitrogen atom-containing compound, an ethylenically unsaturated compound, and a polymerization initiation system. The printing medium has a microstructure of distinct domains of the latex copolymer and the elastomeric block copolymer in a matrix of the other components. The printing medium is typically supported on a substrate to form a printing plate. The printing medium is photosensitive, and is imaged by exposure to actinic radiation through a photographic negative film. The unexposed portions are washed away in a water dispersive medium, without the use of organic solvents, producing a printing plate which, after drying and postexposure to UV light, is ready for printing.

Abstract: Photopolymer platemaking apparatus comprises a tilting bucket assembly comprising a tilting bucket having a lip, a substantially vertical wall associated with the tilting bucket, and positioning means for maintaining the lip in contact with a substantially vertical wall during tilting of the tilting bucket from an upright position to a pre-pouring position, and for separating the lip from the substantially vertical wall as the tilting bucket tilts from the pre-pouring position to a pouring position. Preferably, the positioning means additionally moves the tilting bucket from the pouring position to the post-pouring position, and from the post-pouring position to the upright position, and maintains the lip in contact with the substantially vertical wall during movement of the tilting bucket from the post-pouring position to the upright position.

Abstract: A radiation-sensitive mixture which contains compounds of the formula I which generate under irradiation sulfonic acids and are cleavable by the latter ##STR1## in which R.sup.1 is an unsubstituted or substituted alkyl, fluorinated alkyl, perfluoroalkyl or aryl radical,R.sup.2 is a hydrogen atom, an unsubstituted or substituted alkyl radical, or an unsubstituted or substituted aryl radical, (R.sup.1 --SO.sub.2 --O--).sub.n X--, or R.sub.3 O--,R.sup.3 and R.sup.4 are identical or different and are unsubstituted or substituted alkyl, cycloalkylalkyl, cycloalkenylalkyl or aralkyl radicals, in which 1 to 3 aliphatic CH.sub.2 or CH groups are optionally replaced by one or more of NR.sup.5, O, S, CO, CO--O, CO--NH, O--CO--NH, CO--NH--CO, NH--CO--NH, SO.sub.2, SO.sub.2 --O or SO.sub.2 --NH, or unsubstituted or substituted alkenyl, alkynyl, cycloalkyl or cycloalkenyl radicals, or R.sup.3 and R.sup.4 are mutually linked to form an unsubstituted or substituted heterocyclic ring,R.sup.

Abstract: Ligomeric sulfonic acid derivatives having repeating units of the formula I ##STR1## in which R.sup.1 is an alkyl, haloalkyl or aryl radical,R.sup.2 is a hydrogen atom, an alkyl, alkenyl or aryl radical or the group (R.sup.1 --SO.sub.2 --O--).sub.n X--,R.sup.3 is a cycloalkylenedialkyl, cycloalkenylenedialkyl, arylenedialkyl, heteroarylenedialkyl group, alkylene, alkenylene, alkynylene, cycloalkylene or arylene group,X is an alkylene, cycloalkylene or arylene group Y is O, S, CO, CO--O, SO.sub.2, SO.sub.2 --O, NR.sup.4, CO--NH, O--CO--NR.sup.5, NH--CO--NR.sup.5 or NR.sup.5 --CO--O,Z is O, CO--NR.sup.6, O--CO--NR.sup.6 or NH--CO--NR.sup.6,R.sup.4 is an acyl radical,R.sup.5 is a hydrogen atom or an alkyl-, cycloalkyl, alkenyl, alkynyl or aryl radical,R.sup.6 is an alkyl, cycloalkyl, alkenyl, alkynyl or aryl radical,k is 0, 1, 2, 3 or 4,m is an integer greater than 1 andn is 1, 2 or 3,generate sulfonic acids under irradiation and are cleavable by the latter.

Abstract: Flexographic photosensitive printing plates are made with formulations comprising triblock polymers of poly(vinylpyridine)-poly(butadiene) or poly(isoprene)-poly(vinylpyridine). The polymers may be quaternized. When made with quaternized polymers, the plates after imaging with UV may be developed in aqueous solutions.

Abstract: Provided is an electrophotographic photoreceptor which comprises an electrically conductive support and a photoconductive layer comprising at least an organic photoconductive compound and an alkali and/or alcohol soluble binder resin provided on said support and which is used for making a lithographic printing plate therefrom by electrophotographically forming a toner image and decoating the photoconductive layer of non-image portion other than the toner image portion by contacting with an alkaline decoating solution, wherein an arithmetical mean deviation of profile (Ra.sub.1) of the surface of said electrically conductive support having said photoconductive layer thereon is 0.3-1.0 .mu.m and a ratio of Ra.sub.2 /Ra.sub.1 of an arithmetical mean deviation of profile (Ra.sub.2) of the surface of said photoconductive layer and the (Ra.sub.1) is 0.5-1.0. The image formed on the printing plate is free from indentation at the edge of the image. Resolution and sharpness of the image are improved.

Abstract: A photopolymer useful in preparing water-developable, solid printing plates is prepared by preparing a urethane prepolymer by reacting polyoxyalkylene diols or polyester diols, or a mixture thereof, with an excess of diisocyanate, followed by chain extending the resulting prepolymer mixture with an alkyldialkanolamine, then reacting the chain-extended product with a hydroxyalkyl(meth)acrylate. The resulting photopolymer is suitably formulated with additional photoactive (meth)acrylate monomers or oligomers and photoinitiator for casting or extrusion on a substrate to form a flexographic printing plate. Following UV exposure of the plate through a negative, unexposed areas can be removed by washing with a slightly acidic aqueous medium, to give a plate with a desirable relief image. The use of the aqueous washout solution as opposed to organic solvents minimizes pollution problems.

Abstract: The present invention relates to a letterpress for transferring on which a dot-like fine form plate surface is formed closely resembling a photoimage, and to a method of transferring by use of the letterpress for transferring. The letterpress is formed by exposing a photosensitive resin through a photofilm to a parallel light to harden the film of the photosensitive resin corresponding to the lightscreening area of the photofilm. The area of the photo resin other than the hardened film is then removed by rinsing with water to form the letterpress which has a convex corresponding to the light-penetrating area of the photofilm. The convex is then directly coated with various dyes and press printed on and transferred to a transfer material, or the convex is coated with a photosensitive resin and press printed on a transfer material.

Abstract: A flexographic printing plate comprising in the following order: a flexible substrate, a photohardenable composition, and a colloidal vanadium oxide antistatic layer. The antistatic layer provides protection from static induced defects until and after the flexographic plate is processed.

Abstract: Flexographic photosensitive printing plates are made with formulations comprising block polymers having an architecture of BA, CBA or CBCA, where A is poly(vinylpyridine), B is poly(butadiene) or poly(isoprene) and C is styrene. The polymers may be quaternized or neutralized with an organic acid. When made with quaternized polymers, the plates after imaging with UV may be developed in aqueous solutions. The block polymers offer further advantages as to ease of synthesis, safety and improved resolution.

Abstract: Flexographic photosensitive printing plates are made with formulations comprising triblock polymers of poly(vinylpyridine)-poly(butadiene) or poly(isoprene)-poly(vinylpyridine). The polymers may be quaternized or neutralized with an organic acid. When made with quaternized polymers, the plates after imaging with UV may be developed in aqueous solutions. The acid neutralized polymers offer further advantages as to ease of synthesis, safety and improved resolution.

Abstract: The invention provides a device for offset and similar printing from a continuous tone original to produce a halftone image on a photosensitive layer comprising means for screening the information via a first array of parallely extending lines of effective minimum optical density and a second array of parallely extending lines of effective maximum optical density, the arrays being interposed to form a composite array of substantially parallel, spaced-apart, alternating lines of effective maximum and minimum optical density, the lines delimiting therebetween zones of effective graduated optical density, the gradient inside each zone progressively varying from low optical density adjacent lines of the first array to high optical density adjacent lines of the second array, the spacing of lines of the first array being between about 100 and 400 lines per inch and wherein the resulting thickness of each reproduced line on a resulting developed photosensitive layer, generated by screening the information via the ar

Abstract: A method and associated apparatus for forming an image replication medium on a surface of a printing plate or cylinder in which the surface is initially coated with a layer of photopolymer liquid. Thereafter, selected areas of the layer of liquid coated on the surface are hardened by exposure to a beam produced by a computer controlled laser to provide a surface cylinder having an image replication medium with a desired pattern.

Abstract: A photosensitive resin printing plate which can provide printed matter with good ink coverage and little dot gain, and a plate making apparatus used therefor.

Abstract: A seamed flexible imaging member and a method of constructing a flexible imaging sheet is disclosed. The method of constructing a flexible imaging sheet comprises the steps of overlapping and forming. In the step of overlapping, a first marginal end region and a second marginal end region of the sheet are overlapped. In the forming step, a substantially planar surface is formed, extending in a direction transverse to the sheet with one end of the planar surface being integral with the sheet adjacent one end of the sheet and the other end of the planar surface being integral with the sheet adjacent the other end of the sheet, for securing the first marginal end region and the second marginal end region to one another by a seam. The seamed flexible imaging member comprises a sheet having a first marginal end region and a second marginal end region.

Abstract: A radiation sensitive composition comprises a radiation sensitive material and a dye which dye undergoes a colour change in the radiation-struck areas on image-wise exposure of the composition and a colour change when the exposed and developed composition is heated to a temperature of at least 180.degree. C.

Abstract: A lithographic printing plate for use on a printing press, with minimal or no additional processing after photoexposure, comprises a printing plate substrate; a photosensitive hydrophilic layer having a polymeric hydrophilic binder and a photopolymerizable, photocrosslinkable or photorearrangeable compound capable of promoting insolubilization or hardening in areas of photoexposure; and a photosensitive hydrophobic layer having a polymeric hydrophobic binder and a photopolymerizable, photocrosslinkable or photorearrangeable compound capable of promoting insolubilization or hardening in areas of photoexposure.

Abstract: A method for preparing a printing plate is disclosed. The method comprises contacting a heat sensitive medium, comprising a support and provided thereon a heat transfer layer containing a colorant, a heat fusible substance and a photo-curable composition, with a recording material having a hydrophilic recording surface through the heat transfer layer, applying heat in an image pattern to the contacted materials to transfer the image onto the recording material, and exposing the transferred image to actinic radiation to cure the transferred image.

Abstract: Flexographic photosensitive printing plates are made with formulations comprising triblock polymers of poly(vinylpyridine)-poly(butadiene) or poly(isoprene)poly(vinylpyridine). The polymers may be quaternized. When made with quaternized polymers, the plates after imaging with UV may be developed in aqueous solutions.

Abstract: Disclosed is an eluting solution for eluting a non-image area of an electrophotographic printing plate having a toner image formed and fixed thereon by electrophotography, to expose a hydrophilic substrate or a substrate that can be rendered hydrophilic. This eluting solution is an aqueous solution containing at least an alkali chelating agent.

Abstract: Disclosed is a photosensitive resin composition which has improved water developability and storage stability. The composition comprises(I) crosslinked resin particles prepared by a post-emulsion method from(a) a base resin having a glass transition temperature (Tg) of 0.degree. C. or less and a polymerizable double bond,(b) a monomer which, when polymerized, provides a resin in which Tg is 20.degree. C. higher than that of the base resin, or a resin in which Tg is 20.degree. C. higher than that of the base resin,(c) a polyvinyl compound, and(d) a polymerization initiator(II) a photopolymerizable unsaturated monomer, and(III) a photopolymerization initiator.

Abstract: The present invention relates to a letterpress for transferring on which a dot-like fine form plate surface is formed closely resembling a photoimage, and to a method of transferring by use of the letterpress for transferring. The letterpress is formed by exposing a photosensitive resin through a photofilm to a parallel light to harden the film of the photosensitive resin corresponding to the lightscreening area of the photofilm. The area of the photo resin other than the hardened film is then removed by rinsing with water to form the letterpress which has a convex corresponding to the light-penetrating area of the photofilm. The convex is then directly coated with various dyes and press printed on and transferred to a transfer material, or the convex is coated with a photosensitive resin and press printed on a transfer material.

Abstract: A new liquid cleaner composition is provided for the mild and gentle removal of polymeric materials from sufaces without leaving any residues. The said new cleaner composition is an emulsion of the water-in-oil type comprising an aqueous phase finely dispersed in a continuous phase selected from the group consisting of nonflammable, fire-retardant, high-boiling, and fire-retardant and high-boiling organic phases, the volume ratio of the finely dispersed aqueous phase to the continuous organic phase being in the range of from 90:10 to 10:90. The new liquid cleaner composition can contain alcohols, surface-active agents and further useful additives. The new liquid cleaner composition is most preferably used in the process for preparing photopolymerized flexographic relief printing plates as the developer for washing out the non-irradiated and thus non-photopolymerized areas of the imagewise irradiated relief-forming recording layers of the said flexographic relief printing plates.

Abstract: A method for forming plate characters in a half-tone gravure platemaking process wherein the laser beam is moved so that it will be irradiated on a light sensitive material for forming a plate character on the light-sensitive material by exposure. The plate character is made with a frame portion and a filling portion. The frame portion is formed with continuous groove-form cells which have a predetermined length and width and dot-form projections are formed in the groove-form cells for preventing ink flow. The filling portion is formed by dot-form cells which have a shadow-portion dot percentage.

Abstract: Disclosed is a process for preparing a cylindrical rotary screen printing stencil to made it suitable for use in a screen printing machine.In the process the steps of application of a photosensitive coating, drying, pattern-wise exposure, development and hardening are carried out while the end rings are already fitted in the ends of the screen.Described is also a system of devices suitable for carrying out said process.