Abstract: A method of manufacturing an engraved plate used in intaglio printing, said plate being engraved by a tool, for example a laser beam, characterized in that the engraving tool uses data from a depth-map, based on a three-dimensional raster image of the document to be printed.

Abstract: A resist composition contains (A1) a resin having a structural unit represented by the formula (I), (A2) a resin being insoluble or poorly soluble in alkali aqueous solution, but becoming soluble in an alkali aqueous solution by the action of an acid, (B) an acid generator, and (D) a compound represented by the formula (II), wherein R1 represents a hydrogen atom or a methyl group; A1 represents a C1 to C6 alkanediyl group; R2 represents a C1 to C10 hydrocarbon group having a fluorine atom; ring W1 represents a C2 to C36 substituted heterocyclic ring; R3 represents a C1 to C30 hydrocarbon group, and one or more —CH2— contained in the hydrocarbon group may be replaced by —O— or —CO—.

Abstract: The present invention relates to the implementation of minute patterns and thus improving pattern resolution and transcription property. Provided is a printing substrate for a liquid crystal display comprising a transparent insulating substrate, and a material layer for dry etching formed on an upper surface of the transparent insulating substrate, the material layer for dry etching constituting a printing pattern, and a manufacturing method of a printing substrate for a liquid crystal display comprising forming a material layer on a transparent insulating substrate, applying a photo resist along a printing pattern on the upper side of the material layer, dry-etching the material layer along the printing pattern using the photo resist as an etching mask, and striping the photo resist.

Abstract: An intaglio printing plate includes a substrate and a photosensitive resin film provided on the substrate. The photosensitive resin film includes a plurality of concave patterns whose depths increase as aperture widths increase.

Abstract: A method of manufacturing an engraved plate used in intaglio printing, said plate being engraved by a tool, for example a laser beam, characterized in that the engraving tool uses data from a depth-map, based on a three-dimensional raster image of the document to be printed.

Abstract: Processes comprising providing a layer composite comprising a layer of photopolymerizable material and a removable substrate film disposed on one side of the layer of photopolymerizable material, wherein the photopolymerizable material comprises an elastomeric binder, an ethylenically unsaturated monomer and a photoinitiator; and (a) miter-cutting two edges of the layer composite to be joined, to form two miter-cut ends; (b) providing a hollow cylinder on a rotatably mounted support cylinder, wherein the hollow cylinder has an outer surface and is in a temporarily locked position relative to the support cylinder; (c) applying an adhesion-promoting layer to the outer surface of the hollow cylinder; (d) applying the layer composite to the hollow cylinder bearing the adhesive-promoting layer, wherein the layer composite is disposed on the hollow cylinder such that the removable substrate film faces away from the hollow cylinder and the two miter-cut ends lie substantially one on top of the other, but not overlap

Abstract: An article includes a polymeric film having a major surface, a discontinuous layer of a catalytic material on the major surface, and a metal pattern on the catalytic material. The discontinuous layer of catalytic material has an average thickness of less than 200 angstroms. Methods of forming these articles are also disclosed.

Abstract: The present invention relates to printable security paper that includes a region capable of receiving printed indicia on the front side and on the reverse side which are observable in reflected light and form an image observable in transmitted light, as security element protecting against two-sided copying, characterized in that such region is a screened region having an average overall opacity less than the opacity of the vellum part of the rest of the paper, said screened region being made up from alternations of vellum miniregions, having an approximately constant thickness equal to that of the vellum part of the rest of the paper, and of miniregions of reduced opacity because of their smaller thickness compared with the vellum miniregions. The invention also relates to the security document obtained with this paper.

Abstract: The invention concerns a security document comprising, as security element against recto/verso copying, indicia present on both sides and capable of being viewed under reflected lighting and forming an image capable of being viewed under transmitted light. The invention is characterized in that said indicia comprise lines and form said image with 3D effect.

Abstract: Compounds of the Formula (I), wherein L1, L?1, L?1, L2, L?2, L?2, L3, L?3, L?3, L4, L?4 and L?4 for example are hydrogen or COT; R, R? and R? for example are hydrogen, C6-C12aryl or C3-C20heteroaryl; X, X? and X? for example are O, S, single bond, NRa or NCORa, T is for example hydrogen, C1-C20alkyl, C3-C12cycloalkyl, C2-C20alkenyl, C5-C12cycloalkenyl, C7-C18cycloalkylenaryl, C5-C18cycloalkylenheteroaryl, C6-C14aryl, providedthat at least one of R, R? or R? is unsubstituted or substituted C3-C20heteroaryl; and Y is an inorganic or organic anion; are suitable as photolatent acid generators.

Abstract: Compounds of the formula (I), wherein X is a single bond, CRaRb O, S, NRC, NCORC, CO, SO or SO2; L, L1, L2, L3, L4, L5, L6, L7 and L8 are for example hydrogen, R1 or COT; T denotes T1 or O-T2; T1 and T2 for example are hydrogen, C1-C20alkyl, C3-C12cycloalkyl, C2-C20alkenyl, C5-C12cycloalkenyl, C6-C14aryl, C3-C12heteroaryl, C1-C20alkyl substituted by one or more D, C2-C20alkyl interrupted by one or more E, C2-C20alkyl substituted by one or more D and interrupted by one or more E or Q; R1, R2, R3, R4, Ra, Rb and Rc are T1; D is for example R5, OR5, SR5 or Q1; E is for example O, S, COO or Q2; R5 and R6 for example are hydrogen, C1-C12alkyl or phenyl; Q is for example C6-C12bicycloalkyl, C6-C12bicycloalkenyl or C6-C12tricycloalkyl; Q1 is for example, C6-C14aryl or C3-C12heteroaryl; Q2 is for example C6-C14arylene or C3-C12heteroarylene; Y is an anion; and M is a cation; provided that at least one of L, L1, L2, L3, L4, L5, L6, L7 and L8 is other than hydrogen; and provided that (i) at least one of T1 or T2 is a g

Abstract: Compounds of the formula (I), wherein X is a single bond, CRaRbO, S, NRc or NCORc; Z is formula (II) or C3-C20heteroaryl; L, L1, L2, L3, L4, L5, L6, L7 and L8 for example independently of one another are hydrogen or an organic substituent; Ra, Rb and Rc independently of one another are hydrogen or an organic substituent; R is for example is C5-C20heteroaryl or C6-C14 aryl; and Y is an inorganic or organic anion; are suitable as photolatent acid generators.

Abstract: A laser-decomposable resin composition contains: a compound including at least one structure selected from a carboxyl group and a carboxylic acid anhydride structure and at least one hetero atom selected from N, S and O atoms other than the structure; and a binder polymer.

Abstract: An optical imaging head for direct engraving of flexographic printing plates, comprising: at least two groups of radiation sources, each group comprising at least one radiation source, wherein the radiation sources within each group emit radiation having the same intensity and spot size, different from the intensity and spot size of radiation sources in the other groups, said groups of radiation sources operating simultaneously.

Abstract: A method of fabricating a master stamper/imprinter for manufacturing a patterned recording medium by nano-imprint lithography comprises steps of: (a) providing a substrate having a surface; (b) forming a layer of a hybrid resist material on the surface, the resist layer having an exposed upper surface; (c) subjecting selected areas of the exposed upper surface of the resist layer to an energy beam to form therein a latent image of a topographical pattern to be formed in the resist layer and having a correspondence to a pattern to be formed in a patterned recording medium; and (d) developing the latent image into the topographical pattern in the resist layer, wherein only those areas of the resist layer which have received an energy beam exposure dose between a positive-tone threshold dose D0p and a negative-tone threshold dose D0n are developed.

Abstract: There is provided an alkaline soluble positive-type photosensitive composition having an infrared wavelength range laser sensitive characteristic. There is also provided a positive-type photosensitive composition not requiring any burning operation, capable of attaining a requisite and sufficient close fitness in coating operation under a condition of indoor working room humidity of 25 to 60%, capable of attaining a development not producing any residuals while keeping a high sensitivity, cutting it with a sharp contour, attaining a quite hard resist film and improving an anti-scar characteristic in a handling before developing operation. This composition includes an alkaline soluble organic high molecular substance having a phenolic hydroxyl group; photo-thermal conversion substance for absorbing infrared rays of an image exposure light source; and a close-fitness modifying agent such as polyvinylpolypirrolidone/polyvinylacetatecopolymer and the like.

Abstract: Security documents (e.g. passports, currency, event tickets, and the like) are encoded to convey machine-readable multi-bit binary information (e.g., a digital watermark), usually in a manner not alerting human viewers that such information is present. The documents can be provided with overt or subliminal calibration patterns. When a document incorporating such a pattern is scanned (e.g. by a photocopier), the pattern facilitates detection of the encoded information notwithstanding possible scaling or rotation of the scan data. The calibration pattern can serve as a carrier for the watermark information, or the watermark can be encoded independently. In one embodiment, the watermark and the calibration pattern are formed on the document by an intaglio process, with or without ink. A photocopier responsive to such markings can take predetermined action if reproduction of a security document is attempted.

Abstract: A laser-engravable flexographic printing element comprising an elastomeric, relief-forming, laser-engravable, thermally and/or photochemically crosslinkable layer comprising, as binder, at least 5% by weight of syndiotactic 1,2-polybutadiene having a content of 1,2-linked butadiene units of from 80 to 100%, a degree of crystallinity of from 5 to 30% and a mean molecular weight of from 20,000 to 300,000 g/mol on a flexible, dimensionally stable support. The elastomeric, relief-forming, laser-engravable layer preferably comprises: (a) from 50 to 99.9% by weight of one or more binders as component A consisting of (a1) from 5 to 100% by weight of syndiotactic 1,2-polybutadiene having a content of 1,2-linked butadiene units of from 80 to 100%, a degree of crystallinity of from 5 to 30% and a mean molecular weight of from 20,000 to 300,000 g/mol as component A1, and (a2) from 0 to 95% by weight of further binders as component A2, (b) from 0.

Abstract: A method is provided for reducing UV exposure to edges of a printing plate which occurs when the printing plate is subjected to UV illumination. The method involves a spray head comprising one or more spray nozzles for spraying edge masking material toward the printing plate and a controller connected to control relative movement between the spray head and the printing plate. The method comprises receiving, at the controller, information related to the locations of the edges of the printing plate. In response to the information received at the controller, the controller provides controlled relative movement between the spray head and the printing plate causes the spray nozzles to spray edge masking material onto the edges of the printing plate. The method may be performed by a variety of apparatus.

Abstract: A gravure printing element is fabricated using a negative-working thermally-imageable coating that is exposed using commercially available diode lasers, the coating being insensitive to ultraviolet light, daylight or visible light, and developable using aqueous media. A gravure etch mask is formed on a printing precursor by applying a coating of thermally-imageable material, curing the coating, imagewise illuminating the cured coating with a laser and removing with a developer the areas of the coating that were not illuminated. The masked precursor is then chemically etched to produce a gravure printing element.

Abstract: A gravure printing blank that can be easily and quickly imaged digitally by means of laser imaging and a method for preparing the same. The gravure printing blank comprises a metallic surface, a pre-polymer layer covering said metallic surface, comprising UV curable materials, photo initiators and binder resins and a photo-tool layer covering said pre-polymer layer.

Abstract: There is provided a photogravure plate making method capable of performing a quite superior photogravure plate making operation while it has a requisite and sufficient developing latitude under non-heating condition after forming a coating film and while applying a positive O-type thermal resist.

Abstract: In order to simplify the sequence of creating a mask, in particular for producing a printing plate, and at the same time to improve the quality of the printing plate produced by means of a mask, the use of laser-induced thermal transfer is provided. The structure information is applied directly to the surface of a printing plate carrier during the creation of a mask, by means of a thermal transfer film and a laser image-setting unit, so that by means of the structure information applied, differentiation with regard to image points and non-image points can be carried out directly in order to produce a printing plate.

Abstract: A system and method for selectively process material on a processing surface of a printing form to create a fine structure or pattern for images or text. At least one fiber laser comprising a pump source and a laser fiber is provided. A laser gun is mounted adjacent the printing form and has at least a focusing optics. The fiber laser outputs a laser beam which is diffraction-limited to permit the focusing optics to focus the laser beam onto the processing surface of the printing form as a spot having a spot size sufficiently small to process the processing surface to create the fine structure or pattern images or text.

Abstract: Security documents (e.g. passports, currency, event tickets, and the like) are encoded to convey machine-readable multi-bit binary information (e.g., a digital watermark), usually in a manner not alerting human viewers that such information is present. The documents can be provided with overt or subliminal calibration patterns. When a document incorporating such a pattern is scanned (e.g. by a photocopier), the pattern facilitates detection of the encoded information notwithstanding possible scaling or rotation of the scan data. The calibration pattern can serve as a carrier for the watermark information, or the watermark can be encoded independently. In one embodiment, the watermark and the calibration pattern are formed on the document by an intaglio process, with or without ink. A photocopier responsive to such markings can take predetermined action if reproduction of a security document is attempted.

Abstract: The invention relates to the production of a rotogravure form, preferably comprising a rotationally symmetrical base body (1) and with screen cavities (5) as print information, by means of time-modulated, particularly pulsed laser radiation (9), whereby an erosion support layer (13) is applied to the surface regions (8), provided for information engraving on the base body (1), through which the screen cavities (5) are produced in said surface regions (8) with the laser radiation (9), by means of material ablation. Said erosion support layer (13) is subsequently removed to give burr-free screen cavities (5).

Abstract: An imaging device for preparing a printing surface for a printing operation transfers information related to how the printing precursor should be processed to a processor. The processor is automated to make local adjustments according to the information provided. The information can be transferred for each printing precursor or only when changes occur. The transfer is automated.

Abstract: A liquid transfer article is provided including a support assembly and an imaged surface formed directly on the surface of the support assembly by digital photopolymerization. The support assembly is in the form of a polymeric base, and the liquid transfer article is formed by providing a liquid photopolymer on the surface of the base and then irradiating the polymer with a light source to form the image. The liquid transfer article is reimagable and may be used in gravure printing processes, as well as other printing applications.

Abstract: The present invention relates to a method and materials for producing digitally imaged short-run gravure printing plates and cylinders comprising the steps of providing an image-ready printing blank having a substrate, a UV curing layer, and an IR absorbing, UV-opaque layer. Alternatively, the blank plate can be provided in a two-part construction comprising the metallic substrate and an IR-sensitive film for either processless ablation or ablation transfer imaging Digital imaging of the blank plate is performed using an IR laser which causes selective ablation of areas of the upper IR absorbing layer, thus forming an image structure having exposed and unexposed areas on the underlying UV curing layer. The plate is then flood-cured with UV radiation and washed to better expose the hardened image structure areas of the UV curing layer which have formed and which provide the cells for holding printing ink for use in the gravure printing process.

Abstract: The invention provides a photopolymer package for use in making a hand stamp plate, the package consisting of a sachet containing a photocurable liquid polymer, the walls of the sachet being formed of material capable of being released from the cured photopolymer. Methods for the formation of the package and the hand stamp plate are also provided. The invention eliminates the requirement for the use of a backing layer in the package and thereby offers significant advantages over the prior art in terms of cost and efficiency.

Abstract: A photosensitive printing element is used for preparing flexographic printing plates. The photosensitive printing element comprises (a) a flexible support, (b) a photopolymerizable layer comprising an elastomeric composition sensitive to non-infrared actinic radiation, said layer being soluble, swellable or dispersible in a liquid developer prior to exposure to said non-infrared actinic radiation,and (c) at least one layer comprising an infrared radiation sensitive thermographic material which provides excellent image density (e.g., greater than 3.0) at least in the electromagnetic region of said non-infrared radiation sensitivity and preferably in both the visible and ultraviolet regions of the electromagnetic spectrum upon exposure to infrared laser radiation and thermal development. The mask may be on top of the elastomeric composition or underneath the elastomeric composition (where the flexible support is transparent).

Abstract: A rotogravure printing medium includes a member coated with a film that is selectively removable to produce ink retaining cells. The film is formed by a series of adjacent strip of bead portions of a self-leveling, curable plastic composition which is engravable after curing. The adjacent strip or bead portions merge and self-level after deposition to produce a uniform continuous coating of the plastic composition.

Abstract: The invention relates to a method of manufacturing high-accuracy printing plates, and to a printing plate. The printing plate is manufactured by depositing a layer of substance onto a base plate which is coated with a patterned resist layer. The resist layer can be further processed by means of laser. After the layer of substance has been formed, the base plate and the resist are removed, the layer of substance thus forming the printing plate, the pattern left by the resist forming the printing pattern of the plate.

Abstract: A method for etching a pad-printing cliché and printing an image therefrom on a golf ball comprising providing a film positive of an image; placing the film positive on a pad-printing cliché having a variable relief photocurable pre-polymer surface; curing the pre-polymer that is not blocked by the film positive; removing the film positive from the polymer surface; washing the pad-printing cliché for a first predetermined time sufficient to remove any uncured pre-polymer, such that the pad-printing cliché has the image etched into the pre-polymer surface, the etched image having a substantially homogeneous bottom surface that is free of protrusions formed by screens, normally required for variable relief material, heating the pre-polymer for a second predetermined time sufficient to fully dry the pre-polymer; further curing the pre-polymer exposed by the washing step; providing a golf ball having a dimpled surface; distributing a layer of ink over the etched image in the pad-printi

Abstract: A method of engraving a gravure cylinder having a circumference C for coating a liquid composition on a substrate. The liquid composition contains a concentration of particles having a predetermined particle diameter. The method includes calculating the engraving channel depth Do based on a first ratio of the particle diameter to channel depth (DB/Do). Then, engraving the gravure cylinder according to &thgr;, &agr;, WC, Ww, and Wo.

Abstract: A material for gravure recording by means of coherent electromagnetic radiation for letterpress printing, consisting of a substrate and a crosslinkable layer, with or without a release layer and/or cover sheet, the layer containing at least one ethylenically unsaturated compound, a polymerization initiator and at least one polymeric binder which consists of polyvinyl alcohol and/or at least one copolymer having a substantial proportion of the structural unit and containing a filler having a ceiling temperature of less than 800K, in particular less than 600K, e.g. polystyrene, polymethyl methacrylate, poly(ethylene)ketone, polyoxymethylene or poly(&agr;-methylstyrene), in particular having a spherical or roughly spherical form with a maximum dimension of about 5-10 &mgr;m. The material is very suitable for laser-engravable letterpress printing plates.

Abstract: Photopolymeric gravure printing plates which are to be developed with water or water/alcohol mixtures after imagewise exposure and have, arranged one on top of the other on a dimensionally stable substrate, a layer (A) which may be bonded to the dimensionally stable substrate by an adhesion-promoting layer and is crosslinkable by actinic radiation, a layer (B) which is sensitive to IR radiation and, if required, a parting layer arranged between layer (A) and layer (B), and a peelable protective film applied to the layer (B), are produced by a process in which the layer (A) consists of a mixture of at least one polymeric binder which is soluble or dispersible in water or water/alcohol mixtures, copolymerizable ethylenically unsaturated organic compounds which are compatible with this polymeric binder, a photoinitiator or photoinitiator system and, if required, further assistants, the parting layer which may be arranged between layer (A) and layer (B) is oxygen-permeable and the layer (B) sensitive to IR radiat

Abstract: The present invention is directed to a pre-inked thermoplastic foam which is utilized to form a relief image which includes open cells in the area that is designed to transfer ink and enclosed or sealed cells in the area which is designed to be impermeable to ink or other print medium. The present invention also includes the method of using and manufacturing the pre-inked foam.

Abstract: A method for compensating for image distortion imparted on a flexographic printing plate is disclosed. The compensation scheme reduces the distortion effect caused by stretching of the image when the printing plate is wrapped around the cylindrical drum of a printing press. The compensation scheme predicts the localized distortion on different parts of the image caused by variations in the undercut depth and density of the image features on the plate. By so doing, the scaling factor is varied in accordance with the predicted localized distortion in the different parts of the image, so as to minimize the distortion effect over the entire printing plate.

Abstract: This invention provides making a rotogravure printing medium which includes a member coated with a film that is selectively removable to produce ink-retaining cells. A series of adjacent strip or bead portions of a self leveling, curable plastic composition which is engraveable after curing is provided on the surface of the member. The adjacent strip or bead portions merge and self level at and after deposition to produce a uniform, continuous coating of the plastic composition.

Abstract: In a method of three-dimensionally patterning the surface of a printing or embossing cylinder the surface of the cylinder is irradiated with exposure beams in accordance with the desired pattern and then the surface is patterned in accordance with the exposure. To achieve particularly fine structuring of the cylinder surface, the radiation dots serving to expose the surface are produced by means of beams which, before impinging on the surface of the cylinder, to form fine structures, are modified in accordance with the desired pattern by means of a beam-forming element. The pattern of the respective radiation dot which is impinged on to the cylinder surface is moved synchronously with respect to the movement of the cylinder surface in accordance with the rotary movement thereof.

Abstract: A printing plate material producing prints with inhibited background staining is provided by formation of a photosensitive layer comprising nitrocellulose, a black coloring agent, e.g. carbon black, and an organic binder and having (1) a surface roughness of not greater than Rmax. 2.0 .mu.m or (2) a surface tension equivalent to a wettability index of not greater than 36 dyn/cm on a support. The nitrocellulose has a nitrogen content of 11 to 12.5% and a solution viscosity of about 1 to 1/8 second. The organic binder includes polyester resins such as solvent-soluble, noncrystal-line, linear, oil-free aromatic polyesters. Based on 100 parts by weight of the organic binder, the amount of nitrocellulose is about 5 to 300 parts by weight and that of the black coloring agent is about 0.5 to 50 parts by weight. The photosensitive layer may contain a crosslinking agent, e.g. melamine resin, and/or a water repellent, e.g. a silicone compound or a fluorine-containing compound.

Abstract: Photopolymeric gravure printing plates which are to be developed with water or water/alcohol mixtures after imagewise exposure and have, arranged one on top of the other on a dimensionally stable substrate, a layer (A) which may be bonded to the dimensionally stable substrate by an adhesion-promoting layer and is crosslinkable by actinic radiation, a layer (B) which is sensitive to IR radiation and, if required, a parting layer arranged between layer (A) and layer (B), and a peelable protective film applied to the layer (B), are produced by a process in which the layer (A) consists of a mixture of at least one polymeric binder which is soluble or dispersible in water or water/alcohol mixtures, copolymerizable ethylenically unsaturated organic compounds which are compatible with this polymeric binder, a photoinitiator or photoinitiator system and, if required, further assistants, the parting layer which may be arranged between layer (A) and layer (B) is oxygen-permeable and the layer (B) sensitive to IR radiat

Abstract: The present invention relates to a photosensitive relief or intaglio printing plate comprising a base and a photocurable photosensitive layer formed on the base, the photocurable photosensitive layer containing a dye precursor which forms a dye upon irradiation of actinic light. A relief (convex) pattern or a concave pattern can be recognized by coloring, thereby facilitating the printing plate inspecting work. The developing solution used is not colored or contaminated.

Abstract: A method for producing a printing plate which involves forming an image on the surface of a sheet having open cells by selectively applying a thermal exposure to the surface of the sheet. The sheet is a thermoplastic resin preferably having melting point between about 50.degree. to 150.degree. C. The resulting printing plate has a planar surface with no relief sections; instead there are porous and nonporous sections, with the porous sections being permeable to ink infused within the printing plate. A method of printing using the above plate is also disclosed.

Abstract: A novel imaging process is disclosed comprising preparing microcapsules having an elongation of less than 1%, adhering the microcapsules to a substrate then imagewise rupturing certain of said microcapsules upon selective application of a thermal energy input comprising a .DELTA.T of at least 115.degree. C. per 1 millisecond. The process makes use of novel microcapsules polymerized at a temperature of from 65.degree. C. to 100.degree. C. which are heat resistant yet heat fracturable upon application of a thermal pulse.

Abstract: A printing material comprises a shaped structure made of a combustible material and an oxidizing agent, or a self-combustible material having an oxidizing agent contained therein, or a mixture of a self-combustible material and a combustible material. The printing material is formed with pits by application of a laser beam with small output power. The printing material may further comprise a light absorber in order to promote absorption of the laser beam in the printing material.

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 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: A novel light-sensitive recording element for preparing relief plates or relief printing plates comprises a dimensionally stable base and at least one photopolymerizable recording layer (A) consisting essentially of at least one polymer as binder, at least one photopolymerization initiator, at least one photopolymerizable olefinically unsaturated compound (monomer) which is compatible with the polymeric binder, and/or photopolymerizable olefinically unsaturated radicals which are linked internally and/or terminally to the polymeric binder, and at least one additive, the said additive or at least one of the said additives being selected from the group consisting of the lecithins of the general formulae I and II ##STR1## where R.sup.1 and R.sup.2, which may be identical to or different from each other, are each C.sub.11 -C.sub.18 -alkyl or C.sub.11 -C.sub.18 -alkenyl, with the proviso that at least one of R.sub.1 and R.sub.2 is C.sub.11 -C.sub.