Abstract: An imaging head for use in a spark-discharge recording apparatus, including a tracking system for monitoring and maintaining the head a fixed distance away from the surface of a recording blank. The tracking system preferably measures the distance between the head and the surface of the blank using a gas source oriented toward the blank's surface and a pressure sensor for measuring the pressure of the gas reflected therefrom. The signal produced by the pressure sensor indicates the size of the gap. The pressue sensor is coupled to a servo system that alters the position of the head to maintain a preselected gap distance.

Abstract: A lithographic printing plate that is transformable by spark-discharge techniques so as to change its affinity for ink. The plate features a layered structure including an ink-receptive substrate, a conductive layer and an ink-repellent coating. The ink-repellent coating contains a dispersion of crystalline metal oxide particles that promote straight-line travel of the spark to the surface of the plate, thereby promoting accurate imaging.

Abstract: A pitch-and-roll adjustment mechanism for use in conjunction with a spark-discharge writing head. The mechanism provides structure for adjusting the physical position of the writing head with respect to a recording medium, and includes a flexure plate capable of flexing through a limited arc in two axes without permanent deformation.

Abstract: A process for filmless production of a ready-to-print printing form and for using it in an offset printing press includes exposing a printing form sensitive in an emission range of light-emitting diodes to an image in an exposure unit by means of a computer-controlled LED bar, passing the exposed printing form through a developing stage wherein the printing form is developed, and then feeding-in the printing form via a high-speed feeding-in device for printing forms, and positioning the fed-in printing form on a plate cylinder; and apparatus for performing the process.

Abstract: To apply a printed image on a printing form, a transfer tape is passed under a recording head, the transfer tape receiving, upon application of energy to the recording head, substance particles which change the surface of the printing form to have, respectively, ink accepting and ink repellent surface areas or, respectively, to fill the cells of a gravure cylinder, the transfer tape then being applied against the printing form and the substance particles therefrom being transferred to the printing form under influence of heat, or other energy, e.g. electrostatic or electromagnetic. Recording on the transfer tape, under control of an electronic control unit, can be carried out on a point-by-point or line-by-line basis at a recording speed which is slow with respect to the speed of operation of the reproducing head applying the substance particles to the printed form, so that information can be stored on the tape while a previously prepared printing form can print on the substrate.

Abstract: A printer comprising a temperature control (A) that sets a recording medium (10) conducted through the printer under motor drive approximately uniformly to a predetermined temperature, comprising a thermal writer (B) that generates a latent character image on the recording medium (10) by local heat application controlled character-dependent, and comprising a developer (C) in which the latent character image is developed by condensation of a color vapor or by color application.

Abstract: A method of imaging a lithographic plate having a printing surface comprises exposing the printing surface to plasma jet discharges between the plate and a plasma jet nozzle spaced close to the printing surface of the plate. These plasma jet discharges are sufficient to remove a layer or layers of the plate to thereby change the affinity of the printing surface for ink and/or water at the points thereof exposed to the discharges, thereby producing image spots on the plate.

Abstract: A method of controlling unwanted degradation of overlapping image points in a sparked-imaged lithographic plate. A suitable conductive sheet having an appropriately selected volume resistivity is placed beneath the conductive metal sheet of the plate, thereby drawing off excess spark energy during the imaging process.

Abstract: An image forming apparatus comprises: an electroconductive substrate; an electroconductive member disposed opposite to the electroconductive substrate; a plate-forming unit for forming an insulating pattern on the electroconductive substrate; a supplier for providing a recording material between the electroconductive substrate and the electroconductive member, the recording material being capable of changing its adhesiveness corresponding to the polarity of a voltage applied thereto; and a voltage source for applying a voltage between the electroconductive substrate and the electroconductive member.

Abstract: A method of imaging a lithographic plate having a printing surface comprising mounting a plate to the plate cylinders of a lithographic press having at least two plate cylinders, a corresponding number of blanket cylinders and an impression cylinder, exposing the printing surface to spark discharges between each plate and an electrode spaced close to the printing surface produced in response to picture signals, the spark discharges producing sufficient heat to change the affinity of each printing surface for printing liquid at the points thereof exposed to the spark discharges thereby producing image spots on each plate corresponding to the picture signals, moving the electrode relative to the plate to effect a scan of the printing surface, and controlling the spark discharges to the plate in accordance with picture signals so that they occur at selected points in the scan so as to form an image of the original document on the printing surface. Imaging apparatus is also disclosed.

Abstract: A thermal direct master for lithography, which comprises a water-resisting substrate and a thermosensitive recording layer formed thereon, which comprises as the main components an inorganic pigment, a binder agent, a thermofusible material and a hydrophilic modified silicon oil. The above-mentioned hydrophilic modified silicon oil may be selected from the group consisting of a carboxyl-modified silicone oil, an alkyl higher alcohol eseter modified silicone oil, an alcohol-modified silicone oil, polyether-modified silicon oil, and an .alpha.-olefin modified silicone oil.

Abstract: A printing member for a press with dampening made by forming on a substrate a chromium layer having an exposed surface with pores or capillaries which render that surface hydrophilic and melting the layer surface at selected image points thereon without contacting the surface so that molten chromium is free to flow to and fill the pores or capillaries at the image points thereby rendering the image points hydrophobic.

Abstract: To prevent engagement of a thermo printing head (23), with a thermo transfer tape (22) directly against a plate cylinder having an unyielding surface, an auxiliary transfer element in ribbon, tape or belt form (24, 24', 35) is provided, which is engaged against the thermo tape, ribbon or belt (22) by a counter roller (25) of yielding material or have a yielding surface; thermally affectable material is transferred from the thermo transfer tape in accordance with image information to be printed on the auxiliary tape (24, 24') for transfer to the plate cylinder or material which is not to print is transferred on the auxiliary tape, and the remainder of the material is transferred from the thermo transfer tape on the tape cylinder (10).

Abstract: A printing member for a press without dampening made by forming on a metal substrate an organic plastic layer having an exposed surface which is highly oleophobic and thermally decomposing the layer surface at selected image points thereon without contacting the surface and without penetrating through the layer so that there is a transformation of the surface structure which renders said surface oleophilic at said image points.

Abstract: A printing member for a press with dampening made by forming on a metal body, e.g. of aluminum, an exposed oxidized surface with a grained surface structure which renders that surface hydrophilic and heating the body surface at selected image points thereon without contacting the surface so that there is a transformation of the surface structure which renders it hydrophobic at the image points.

Abstract: A printing member for a press with dampening is made by forming in a metal body an exposed surface which is cleaned and polished sufficiently to render it oleophilic due to surface tension. Then the surface is heated at selected image points thereon without contacting the surface and without penetrating through the body to create tiny surface fissures or capillaries at the image points which render the surface hydrophilic at the image points.

Abstract: The invention is directed toward a base material for aluminium offset printing plates having improved heat stability comprising an aluminum alloy consisting of from about 0.2 to about 0.6% by weight of iron, less than about 0.25% by weight silicon and copper combined, from about 0.1 to about 0.3% by weight manganese and the remainder being aluminum and trace production impurities, said base material further characterized as containing secondary precipitates in the form of phases of the Al Mn Si: Al Fe: Al Mn type which bear a ratio to one another of from about 1:1:2 to about 1:1:3, the mean particle size being from about 0.25 to about 0.010 micron with a maximum particle size of less than about 0.3 micron and further containing a precipitation structure with a degree of dispersion of less than about 50 phases per cubic micron and a process for producing such material. The sheet material according to this invention may be uniformly roughened in either HCl or HNO.sub.

Abstract: A printer capable of simultaneously forming planographic printing surface and printing ink images. The printer comprises a control unit, a plate feeding unit for continuously feeding a printing plate formed by coating an oil-repellent sheet with a fusible lipophilic thermal film, a plate making unit having a thermal head for locally and selectively heating lipophilic thermal film according to electric signals to remove portions of the lipophilic thermal film to make a planographic printing surface having a printing area, an inking unit having an inking roller for applying a liquid ink to the planographic printing surface of the printing plate, a transfer unit comprising a platen roller for continuously feeding a recording medium, and a pressure roller for pressing the planographic printing surface of the printing plate against the recording medium to transfer the inked pattern of the printing area to the recording medium.

Abstract: An offset printer having a printing section and a plate making section in a unitary assembly. The plate making section is located above the printing section. The printing section includes a plate drum, a rubber drum, and a press drum. The press drum is disposed above and at a predetermined angle relative to the rubber drum. The diameter of the press drum is at least two times as great as the diameter of the rubber drum.

Abstract: An improved apparatus and process are described in which a direct negative is formed using commercially available multi-stylus recording heads. A negative precursor comprised of a transparent support and an opaque thermoplastic ink layer carried thereon, is brought into contact with an ink receiving medium comprised of a resistive layer and a thin conductive ink receiving layer thereon. Electrical currents are provided by the recording styli of the multi-stylus recording head to the resistive layer to provide sufficient heat to soften regions of the opaque ink brought into contact with the conductive layer, by which regions of said opaque ink are transferred to the ink receiving conductive layer. In this manner, a pattern of opaque ink regions is removed from the surface of said transparent support, whereby a direct negative is formed having light opaque and light transparent regions.

Abstract: A method of forming an ink image with a thermo-sensitive ink by using a printing plate that is used in dry lithographic printing, and printing the ink image onto an object. An ink remover is placed via a thermo-sensitive ink layer that is in a heated state on a printing surface of a printing plate having a part receptive to ink and a part capable of repelling ink. The printing plate and the ink remover are separated after they are cooled so that the ink layer on the part capable of repelling ink is transferred to the ink remover. The ink image obtained on the printing plate or the ink remover is transferred to an object. Printing that does not require maintenance that has been essential to conventional dry lithographic printing becomes possible.

Abstract: A photosensitive lithographic plate is suitable for use in making a water-less lithographic plate which does not require dampening water. The photosensitive lithographic plate has a primer layer containing a hardened gelatin, a photosensitive layer and a silicone rubber layer. The silicone rubber layer and the photosensitive layer are imagewise removed as a result of the imagewise exposure and development so as to expose portions of the primer layer corresponding to an image. The exposed gelatin-containing plate is securely adhered to the substrate and is easily dyeable for examination of the formed image.

Abstract: Printing image carriers for surface printing which have a water accepting surface adapted to have ink accepting surface elements transferred to it by the action of heat and pressure. In order to ensure reliable transfer of such layers keeping to precisely delimited outlines the printing image carrier is of a material which is thermally insulating and whose surface accepts water. The result is the avoidance of excessively rapid conduction away of the heat input from a pressing head which would otherwise be likely to interfere with a precisely delimited transfer of an oleophilic layer or to generally prevent the application of such a layer.

Abstract: This invention describes a direct master for offset printing. The master comprises a thin metal layer, a thermoplastic layer disposed on the metal layer, and a conductive oxide layer evaporated on the metal layer. When this master is subjected to electrical pulses from the styli of a printer, some of the thermoplastic layer diffuses through the oxide layer changing selected regions of the oxide layer to oleophilic regions.

Abstract: For modifying the printing image on a printing image carrier within a printing press the printing image carrier is in the form of a material with ferroelectric properties. Electrodes with or without heat sources are used to delete and write matter on the printing image carrier by polarizing and depolarizing the respective parts of the printing image carrier or the ferroelectric material. The depolarized material is hydrophobic so that it accepts the printing ink whereas the polarized parts are hydrophilic and accept water.

Abstract: An ink jet image transfer lithographic apparatus is coupled to a source for supplying graphics and textual material to an ink jet printhead. The ink jet printhead melts a hydrophobic solid ink and sprays the ink onto a lithographic plate in a predetermined pattern. The solid ink solidifies upon contact with the plate. The plate is then mounted in a lithographic press for lithographic printing. As an alternative, the ink jet printhead may be mounted in a lithographic press for imaging a lithographic plate mounted in the lithographic press or for spraying ink directly onto the plate cylinder of the press. A succession of lithographic plates may be provided around the plate cylinder of the lithographic press and each plate discarded after use, leaving a clean plate on the plate cylinder.

Abstract: An improved process for detackifying imagewise exposed and solvent-developed photopolymeric flexographic relief printing plates wherein an aprotic organic solvent is applied to the surface of the printing plate prior to irradiation with wavelengths in the 200 to 300 nm range.

Abstract: In a laser beam modulation system, e.g. for pattern machining, in which a laser beam is modulated prior to power amplification, an acousto-optic modulator can provide a low beam extinction level when the diffracted beam is used, but the modulator causes an optical frequency change (Dopplar effect) taking the modulated beam outside the laser amplifier passband when both the source and amplifier are low pressure (1 torr) CO.sub.2 lasers.This is overcome by operating at least one of the lasers at an elevated gas pressure thus increasing the lasing amplification bandwidth. Thus a waveguide CO.sub.2 laser can be used as the amplifier but the power available is limited. Preferably a tunable waveguide CO.sub.2 laser source is used tuned to a frequency offset sufficient to accommodate the modulation beam and sidebands within the passband of a conventional low pressure high power CO.sub.2 amplifier laser.

Abstract: A dry presensitized plate for use in making a lithographic printing plate requiring no dampening water during printing, which comprises a support having provided thereon, in order, a light-sensitive layer of microcapsules comprising a photohardenable monomer or a light-sensitive resin and a silicone rubber layer. The dry presensitized plate makes it possible to obtain a dry lithographic printing plate without using any developers and the removal of the silicone rubber layer. Therefore, the development of the dry presensitized plate is simple and economical.

Abstract: Non-tacky, smooth, structureless surfaces of photopolymer relief printing plates for flexographic printing, whose relief layers are prepared in a conventional manner by exposing the photopolymerizable relief-forming layers of flexographic printing plates imagewise to actinic light and washing out the unpolymerized, unexposed areas with a suitable solvent, are produced by a process in which the flexographic printing plates are after-treated with a liquid medium which contains elemental bromine or is capable of forming elemental bromine, and then washed with a neutralization bath, one or more paraffinsulfonates, fatty alcohol ethersulfates or alkyl phosphates or a cationic or anionic surfactant possessing one or more perfluorinated carbon chains being employed in the bromine-containing, liquid medium.The relief printing plates obtained according to the invention are used for flexographic printing.

Abstract: A printing system incorporating a re-usable ink image transfer surface. A material which forms a thin hydrophobic layer is arranged by various techniques over a substantially hydrophilic transfer surface in a configuration which defines the desired latent image in terms of exposed, contiguous hydrophilic and hydrophobic areas. In some cases, a hydrophilic layer may be in direct contact with the hydrophobic layer. Depending upon the configuration of the layers, either an aqueous or oleo ink may be used to develop and print an image. If desired, the layer configuration may be replaced by a different configuration without substantial interruption to the printing process. No photo-induced chemical reaction or latent image developing steps are required at any time. The ink image transfer surface may be a planographic printing screen or a printing screen.

Abstract: Disclosed is an electrophotographic offset master which contains sericite or sericite-containing inorganic pigment as pigment component in back coat layer. This offset master has no fogging on the photosensitive layer and thus causes no stains on printed copies.

Abstract: The present invention relates to a graphic arts film obtained by forming a toner image on a light-transmitting base sheet having a toner-adhesive and ink-repellent coating layer, then fixing the toner image and applying ink onto the surface of the base sheet to thereby selectively enhance the optical density of the toner image area on the coating layer, and a method of preparing the same.The present invention permits easy and inexpensive production of a graphic arts film having a sufficiently enhanced optical density, free from pin-holes and capable of being retouched with respect to the image formed thereon.

Abstract: This invention pertains to a process for electrochemically modifying electrochemically roughened aluminum or aluminum alloy-based support materials for printing plates. An aluminum or aluminum alloy-based support material is electrochemically roughened using alternating current in an electrolyte containing at least one from the group consisting of hydrochloric acid and nitric acid. Subsequently, at least one surface of the material is treated in an aqueous electrolyte, with the roughened material being made the cathode. The cathodic treatment results in removal of material from the surface in the order of from 0.1 to 10 g/m.sup.2, and is carried out in an aqueous electrolyte which has a pH value in the range from 3 to 11 and includes at least one water-soluble salt in a concentration ranging from 5 g/l up to the saturation limit thereof. The cathodic treatment is appropriately conducted using direct current at a current density from 3 to 100 A/dm.sup.2, at a temperature from 15.degree. to 90.degree. C.

Abstract: Lithographic printing plates are made by exposing to actinic light a lithographic plate having a water soluble light sensitive layer thereon and a coating of a solvent soluble, UV curable material thereover to form an image in the light sensitive layer and adhere said layer to the overlying UV curable material. The plate is developed with water to remove light sensitive layer and overlying UV curable material in the non-image areas, and the plate is exposed to UV source having an intensity greater than the imaging light to form a press-ready plate having a durable, reinforced cured image thereon.

Abstract: A light-sensitive adduct comprising the combination of a diazo resin having a plurality of pendant diazonium groups and a sulfonated polymer having a plurality of sulfonate groups and a presensitized light-sensitive article comprising a substrate having a light-sensitive coating which is comprised of the light-sensitive adduct on a surface thereof. After imagewise exposure, unexposed portions of the coating are removable by water or aqueous developers.

Abstract: A composite material and method for forming graphics such as letters or numbers that are pressure transferable to a substrate. The composite material includes an accepting tape including a layer of latent adhesive material on a receiving web, and a friable slightly adhesive layer lightly adhered to a donor web. When the layers are pressed together and the composite material is selectively heated in graphic patterns, corresponding portions of the adhesive material and friable layer adhere together so that upon subsequent separation of the layer of adhesive and the donor web portions of the friable layer transfer to the accepting tape in the heated areas to provide graphics. When the graphics are then positioned against a substrate and are pressed against the substrate by rubbing pressure applied through the receiving web, the adhesive layer will tear around the graphic and separate from the receiving web over the graphic so that the graphic will be transferred to the substrate.

Abstract: A conveying mechanism and flexible carrier for transporting a planar printing plate and flexible overlying mask from a flat loading station to a precisely-curved cylindrically-shaped scanning station, and back to the flat loading station, is disclosed. The vacuum carrier used is rigid in one axis and flexible in a second axis, and has a pair of reference strips which define a neutral bending axis for the plate and mask when the latter are wrapped around a pair of precisely machined cylindrical discs. By locating the flexible mask and printing plate outside the neutral axis of bending, both are placed in tension when wrapped around the discs. This maintains uniform contact between the plate and mask and prevents wrinkling of the mask as it overlies the plate.The carrier and discs support the plate and mask within a precise and uniform cylindrical plane for scanning with focussed beams of radiation.

Abstract: A photoconductive plate for printing use having imaged and non-imaged portions. The plate comprises an electroconductive support and a photoconductive layer including a photoconductive material comprising an organic photoconductive pigment and a binder comprising an alkaline soluble phenol resin. The photoconductive plate is subjected to heat treatment at a sufficiently elevated temperature prior to removal of portions of the photoconductive layer so that at least 80% by volume of the non-imaged portion of the photoconductive layer is removed when the photoconductive plate is subjected to treatment with a removing solution. A method for preparing a printing plate. An image is formed on a photoconductive layer and the non-imaged portion of the photoconductive layer is removed by treating the layer with a removing solution.

Abstract: A process for producing a lithographic printing plate is disclosed which comprises exposing and developing a photographic element, coating the element with one or more carboxylated amines or the salts thereof, and subsequently baking the element.

Abstract: Lithographic printing plates are made by exposing to actinic light a lithographic plate having a water soluble light sensitive layer thereon to form an image in said layer. A solvent soluble, UV curable material is adhered to the image in said layer. The plate is developed before or after applying the UV curable material. The plate is exposed to UV source having an intensity greater than the imaging light to form a press-ready plate having a durable, reinforced cured image thereon.

Abstract: A ribbon for thermal printing comprising a transfer coating and a substrate which is a polyurethane resin containing electrically conductive carbon black.

Abstract: A method of increasing the strength, abrasion resistance, solvent resistance, and press life of a lithographic image comprising a layer of light-reacted light sensitive material and an outer layer comprising an epoxy resin overlying the light-reacted layer. In the method, the surface of the outer layer is contacted and wetted with an aqueous solution comprising a least about 7% by weight of a boron trifluoride-amine complex. Solvent is evaporated from the solution on the surface to deposit dry boron trifluoride-amine complex on the outer layer and the outer layer is heated in the presence of the complex to cross-link the epoxy resin and form a hard, tough, abrasion-resistant, solvent-resistant and wear-resistant epoxy resin layer at the outside of the image. Further included in the invention are a curing composition adapted for topical application to a lithographic image in carrying out the method of the invention and a planographic printing plate produced thereby.

Abstract: A method for desensitizing an offset printing plate which comprises applying an aqueous desensitizing composition consisting essentially of at least one complex to a non-image area of the offset printing plate having an oleophilic image formed thereon in an amount effective to desensitize said non-image area.

Abstract: An image-forming member for forming a metal grain image of the type containing a reducible metal compound which is able to isolate metal from it when reduced, and a reducing agent being capable of reducing the metal compound so that there may be formed a metal grain image by the metal isolated from the metal compound at the portion of the member subjected to the action of energy for producing a metal grain image-forming ability and thermal energy is characterized by the provision of a capturing means which is capable of capturing by-product produced from the metal compound upon the isolation of the metal from the metal compound.

Abstract: A lithographic printing plate in which the oleophilic imaging areas are formed as a thin cross-linked block copolymer film adhered to the hydrophilic surface of a backing plate. The block copolymer comprises blocks of copolyacrylate and polyurethane wherein the copolyacrylate blocks are a copolymer of a hydroxy-containing acrylate and a second acrylate component comprising one or more esters of acrylic acid or methacrylic acid or mixtures thereof and the polyurethane blocks are formed of polyoxybutylene as the prepolymer component. In forming the printing plate the block copolymer is deposited as a thin film containing an ultraviolet initiator and a cross linking promoter and the cross-linked imaging areas are formed by exposure to ultraviolet radiation.

Abstract: A heat-developable photosensitive material for producing an electrostatic printing master having improved electrostatic characteristics comprises a support, an organic silver salt, a reducing agent, and a binder.

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 lithographic plate are also disclosed.

Abstract: The present invention is concerned with a ribbon for non-impact printing. The ribbon comprises a transfer coating and a substrate which is a polyester resin containing from about 15% to about 40% by weight of electrically conductive carbon black.

Abstract: The method of preparing a lithographic printing plate containing ink receptive printing image areas and water receptive non-printing background areas in which the plate consists of a substrate having on one side thereof in sequence an electrically conductive layer and a photoconductive layer consisting of fully crystalline inorganic photoconductive substance. The method comprises the steps of forming an electrostatic latent image on the surface of said photoconductive layer, developing the electrostatic latent image to define the ink receptive printing image areas on the surface, and applying to the surface an aqueous chromic acid solution.