Abstract: A screen wiper assembly for cleaning the underside of a printing screen in a microcircuit thick film printer. The assembly includes a wiper blade, a movable arm for moving the wiper blade under the printing screen, and a guiding cam and roller for guiding and controlling the movement of the wiper blade.

Abstract: Cleaning apparatus for removing the ink distribution assembly of a printing machine. The ink distribution assembly includes a plurality of rollers which transfer ink from one to the other. The cleaning apparatus includes a portable frame, a cleaning roller mounted on the frame, and attachment means for mounting the cleaning apparatus on the ink distribution assembly such that the cleaning roller is pressed against a roller in the ink distribution assembly under the force of gravity.

Abstract: During a printing operation, an ink pump assembly is driven in a forward direction by a reversible electric motor to pump ink from a source of ink to an inker apparatus. When the printing operation has been almost completed, the direction of operation of the ink pump assembly is reversed to pump reusable ink back to the source of ink. When most of the reusable ink has been pumped back to the source of ink, a valve is actuated to direct the output from the reverse operating ink pump assembly to a waste material receiver. Once the ink has been pumped from the inker apparatus, a valve is actuated to connect the ink pump assembly in fluid communication with a source of clean-up fluid. The clean-up fluid is then pumped from the source to the inker apparatus by forward operation of the ink pump assembly. Once sufficient clean-up fluid has been conducted to the inker apparatus, the ink pump assembly is again connected with the waste material receiver.

Abstract: An automatic cleaning apparatus for a gravure plate cylinder comprises a carriage having a spatula capable of contacting the outer cylindrical surface of a gravure plate cylinder and a solvent sprinkling pipe for sprinkling a cleaning solvent on the outer cylindrical surface of the gravure plate cylinder which is rotated about its axis during the cleaning operation. The carriage is moved in a direction parallel to the gravure plate cylinder by rotating a screw bar, and the spatula of the carriage is pressed against the gravure plate cylinder by a pressure shaft connected to an actuator.

Abstract: A cleansing solution for cleaning components of a planographic printing press to include the printing plate, which includes a solution of a humectant, a buffer, a glycol ether and an organic solvent to which anhydrous aluminum silicate and gum arabic have been added.

Abstract: A method of removing inks and other oily contaminants from printing machines, printing plates and offset blankets using a cleaning aid that is based on a C.sub.6 or higher alkyl ester of a fatty acid, preferably containing 8 to 22 carbon atoms. The cleaning aid does not significantly degrade images on printing plates.

Abstract: A method and apparatus for printing for which turret having a plurality of fountain and doctor blade assembly is translatably, indexably mounted adjacent a transfer roll.

Abstract: A method of washing an offset printing press having a plate cylinder, a rubber blanket cylinder, an impression cylinder, an inking unit a paper thickness compensator and a damping unit. The inking unit and the damping unit include, respectively, inking rollers and damping solution applicator rollers. The offset printing press also includes a washing apparatus. The washing apparatus, when in the wash mode, is placed in engagement with the rubber blanket cylinder of the printing press by control apparatus. Also, in the wash mode, the impression cylinder is engaged with or disengaged from the rubber blanket cylinder by a paper thickness compensator. The usual purpose of the paper thickness compensator is to compensate for the thickness of the stock in running-on mode but is employed herein also to effectuate washing of various rollers and/or cylinders of the printing press.

Abstract: A cleaning system for a printing line having a plurality of printing units which each include a plurality of printing cylinders, such as blanket cylinders and/or plate cylinders. The cleaning system includes a cleaning device associated with each printing cylinder, which includes a rotatable brush roller that is selectively moveable into and out of engagement with the respective printing cylinder. Each cleaning device further includes a cleaning fluid direction tube for applying cleaning fluid to the brush roller to facilitate removal of foreign matter from the printing cylinder during a cleaning operation and a flicker bar that is selectively engageable with the brush roller to effect removal of foreign matter and used fluid carried thereby.

Abstract: A washing device formed as an insert unit on a printing machine for cleaning the outer cylindrical surface of rollers or cylinders includes a washcloth supply roll and a dirty-washcloth take-up roll for a washcloth, a device for saturating the washcloth with washing medium, a device for withdrawing the washcloth from the supply roll by winding the washing device on the take-up roll via an actuable pressure applicator, so that, during a washing operation, the pressure applicator presses the washcloth against a roller or cylinder, the take-up roll being connectible with a feeder device fixed to the machine, the washing device being automatically connectible with a roll-sensing device fixed to the machine when it is slid as an insert unit into position in the machine, an upwardly exposed washcloth section, in the slid-in position, being disposed upstream of a membrane member, as viewed in transport direction of the washcloth, the washcloth section being located beneath a washing-medium dispenser device fixed to

Abstract: In a screen printing apparatus an applicator body is rotatable about its axis to selectively bring one of a plurality of medium supply ducts into active position so that it can deliver the color medium to the substrate. The applicator roller or blade and a strip defining the applicator compartment are provided on the rotatable body for each set of orifices and each distribution duct so that these elements need not be cleaned for color changeover since they remain associated with the color when the applicator is rotated.

Abstract: The invention relates to a method for removing printing ink from guide rollers in a printing press. As a paper web moves along its normal path through the printing press while printing is suspended, a printing ink solvent is sprayed onto the paper web, either upstream or downstream of a printing machine. The printing ink deposits on the rollers are dissolved by the solvent as the sprayed paper web passes over the rollers, and the dissolved printing ink is then wiped from the rollers with a nonsprayed part of the paper web. In accordance with one preferred embodiment, the solvent is sprayed onto the paper web in one or more sinusoidal paths and the guide rollers are subsequently braked, preferably to a complete stop and preferably pulse-wise when the sprayed part of the web and the wiping part of the web passes over the rollers. The duration of the pulses is adapted to the desired cleaning effect.

Abstract: A device for cleaning the working surfaces of a plurality of cylinders in a printing press is provided wherein a plurality of pressing elements are disposed each for selective engagement with the working surface of at least one of the cylinders and a web of cleaning cloth is disposed to move successively over the pressing elements and is selectively urged by the pressing elements into relative rubbing contact with the working surfaces of at least two of the cylinders. A drive for stepwise advancing and arresting the movement of the cleaning cloth with respect to the pressing elements and the working surfaces of the cylinders includes a clean cloth spindle disposed transverse to the stepwise movement for supplying said web of cleaning cloth and a stepwise drivable dirty cloth spindle disposed parallel to the clean cloth spindle and adapted to receive the used cleaning cloth.

Abstract: Method and apparatus capable of automatically cleaning a dampening water supply passage to a plate cylinder in an offset press, as well as an ink supply passage to the late cylinder. The apparatus comprises an operation instruction means producing operation signals in a sequence to driving portions of various means which include ink supply-stopping means, means for supplying a cleaning solvent, cleaning waste recovering means, means for bringing ink supply rollers out of contact with the plate cylinder, means for bringing dampening water supply rollers out of contact with the plate cylinder, and main control means, a start instruction means that starts the operation instruction means, and a manual instruction means. This manual instruction means permits the operator to select either cleaning of only the ink supply passage or cleaning of all the ink supply passage and the dampening water supply passage.

Abstract: The invention provides a cleaner for lithographic printing plates free of aromatic hydrocarbons consisting essentially of from about 3.0% to about 35.0% of a solvent component which is selected from the group consisting of ethoxylates and propoxylates of C.sub.1 to C.sub.4 alcohols; and from about 0.5% to about 7.0% sodium metasilicate; and from about 0.25% to about 6.0% of a non-ionic surfactant selected from the group consisting of polyoxy aryl ethers having a hydrophile-lipophile balance in the range of from about 10.5 to about 11.5; and from about 52.0% to about 96.25% water, wherein said percentages are by weight of the cleaner.

Abstract: A composition for finishing, preserving and cleaning lithographic printing plates composed of a polyol having a molecular weight in the range of from about 50 to about 2,000; a maltodextrin obtained by the enzyme hydrolysis of corn or potato starch, a mixture of a C.sub.18 to C.sub.30 alcohol and an aminated, aliphatic C.sub.8 to C.sub.24 alcohol sulfate with a ratio of alcohol to sulfate ranging from about 1:1 to about 5:1; and a composition of hydrocarbons having a boiling point in the range of from about 175.degree. F. to about 500.degree. F., and a flash point of above about 100.degree. F., preferably containing 100% aliphatic components; and a substituted phenoxypoly(oxyethylene)ethanol having a hydrophile/lipophile balance of from about 8 to about 15; and a mono-, di- or tri-ethanolamine; and water; and an acid to impart a pH to the composition of from about 2.5 to about 6.5; and a buffer to maintain the pH, and preferably a bacteriostat/fungistat component.

Abstract: An improved automatic blanket wash system for offset printing wherein the washing medium is a water-in-oil emulsion containing 5-35 percent by weight water and 65-95 percent by weight of a water insoluble phase that contains certain hydrocarbons in specific proportions and a surfactant having an HLB of 3-11.

Abstract: The specification discloses an apparatus and method for cleaning printing screens or the like work surfaces in which solvent is pumped from a reservoir to the surface to be cleaned at a point closely adjacent a vacuum cleaning tool. The vacuum cleaning tool is connected by a vacuum line to the reservoir and vacuum means are provided to draw a vacuum on the reservoir whereby solvent is delivered to the surface to be cleaned and residue laden solvent is vacuumed off the surface to be cleaned through the vacuum tool and vacuum line. A clean up tray and light panel are provided to facilitate the clean up operation. A control assembly comprising independently or simultaneously actionable foot pedals for control solvent feed and vacuum is provided.

Abstract: A method, and components therefore for cleaning and reclaiming silk screens and the like. The method involves the steps, in general, of handspraying silk screens to be cleaned at a nominal water pressure of 3,000 psi plus or minus 300 psi, and this preferably at a water temperature of from 70 to 140 degrees Fahrenheit. The water circulating system is preferably a closed system that is periodically automatically replenished as needed. This saves a volume of water required, and such water is reclaimed by filtering systems. The filtering structure employed comprises a series of classifier screens of progressively reduced mesh and disposed in mutually superposed position. A further filter is in the form of a disposable bag filter made of paper or other suitable material preferably having a pore size of the order of ten microns. Additional filters are employed as needed. The spray cabinet employed has silk screen support bars and clamping means for clamping the screens in sloping condition.

Abstract: A composition for correcting scratches on the non-image areas of a metal based lithographic printing plate which contains trisodium phosphate, sodium metasilicate, an anionic surfactant and water.

Abstract: Method by cleaning of printing ink and printing mould from the screen of a serigraphical frame (3), where the screen is cleaned with high pressure water to which has been added alkaline washing powder, to loosen the printing ink and the printing mould, thereafter flushing the screen with high pressure water to remove possible remaining printing ink and printing mould and finally to dry the cleaned screen for reuse.

Abstract: A portable containment structure is employed to clean a gripper assembly.

Abstract: The present invention provides an automatic blanket wash system that recirculates a separable mix of water and solvent. The mix is selectively applied to the blanket cylinders by closing a pressure valve in the recirculation system return line and selectively opening valves to spray bars at the blankets. The pressure valve closing causes a pressure build up in the system for the spraying of the mix onto the blankets.

Abstract: Ink cleaning compositions are disclosed which degrade or solubilize broad classes of printing ink residues on printing screens for quick removal by a pressurized water stream. The compositions are essentially non-aqueous and contain N-methyl-2-pyrrolidone (NMP), an oxygenated solvent, such as butyl cellosolve and cyclohexanone, and a surfactant. Alternatingly, compositions containing NMP and tetrahydrofurfuryl alcohol as the primary components are disclosed. Methods of cleaning and reclaiming printing screens which provide synergistic activities are also disclosed. The compositions meet health and safety standards due to their biodegradability, lack of flammability and high threshold limit values.

Abstract: An improved process for restoring the hydrophilic property of stained non-image areas in a lithographic printing plate is described, which comprises treating said lithographic printing plate with a plate cleaner, wherein the improvement comprises using a plate cleaner comprising an aqueous solution containing a silicate and at least one surface active agent selected from the group consisting of cationic surface active agents and amphoteric surface active agents.

Abstract: The present specification discloses an apparatus for washing a rubber blanket cylinder of a printing machine. The apparatus comprises a cleaning cloth which extends between a supply roll and a take-up roll, with control and drive means adapted to rotate the take-up roll in a step-wise manner to thus take up uniform lengths of cleaning cloth. A rotatable guide roller is arranged to press the cleaning cloth between said rolls, against the rubber blanket cylinder, the rotatatable guide roller having a resiliently deformable outer surface across which the cleaning cloth is guided. A reversible brush roller is located upstream of the rotatable guide roller in the direction of rotation of the rubber blanket cylinder, and is in contact with said cylinder, and a cleaning agent supply and a water supply are arranged to feed said brush roller.

Abstract: A method and apparatus enable cleaning of gripper assemblies wherein the grippers are enclosed by a containment structure and cleaned by a liquid spray.

Abstract: A cleaning composition particularly suited for removing dried printing ink residue from a substrate is described comprising a chlorinated hydrocarbon liquid, a petroleum distillate, an aliphatic alcohol and aqueous ammonia.

Abstract: A cleansing agent for lithographic printing plates having substantially reduced aromatic components. The plate cleaner comprises an aqueous mixture of substantially aliphatic hydrocarbons, a composition comprising one or more non-ionic emulsifying agents and/or non-ionic surfactants, an alkaline salt electrolyte and an optional organic or inorganic acid.

Abstract: A non-aqueous liquid chemical formulation for reclaiming silk screens by removing simultaneously the stencil emulsion and ink is described. The silk screen is contacted with the liquid for a period sufficient to loosen the hardened stencil emulsion and the ink from the surface of the silk screen. The non-aqueous liquid chemical formulation is typically placed in a carbon steel tank at ambient temperature and the silk screen is immersed in the liquid for approximately five minutes. Alternately, the silk screen can be sprayed with the liquid formulation and allowed to soak for approximately seven minutes. The softened ink and stencil emulsion are then removed by using a high pressure water jet stream. The formulation contains an alkali metal hydroxide, a monohydric or polyhydric alcohol, a glycol ether, a surfactant, aliphatic and/or aromatic hydrocarbons and a wax.

Abstract: A compositoin suitable for production of a fountain solution for lithographic printing operations, which comprises tetrapotassium pyrophosphate, monosodium phosphate, a sequestrant, a water-soluble polyethylene glycol, sodium carboxymethyl cellulose, a low- or non-foaming nonionic detergent, an anionic detergent and a polysiloxane. The invention is also directed to a concentrate and a fountain solution, both of which comprise a mixture of water and the foregoing composition.

Abstract: Azeotrope-like compositions consisting essentially of 1,1,2-trichloro-1,2,2-trifluoroethane, acetone and n-hexane have utility as degreasing agents and as solvents to remove polymeric binders containing inks, such as carbon black which are used in copy machines.

Abstract: Azeotrope-like compositions consisting essentially of 1,1,2-trichloro-1,2,2-trifluoroethane, acetone and cyclopentane have utility as degreasing agents and as solvents to remove polymeric binders containing inks, such as carbon black which are used in copy machines.

Abstract: A developed photopolymer layer is completely removed from a support substrate of a printing plate. Such photopolymer is developed by photoinitiated polymerization from at least one water-soluble ethylenic monomer and includes a partially saponified polyvinyl acetate. For removal, the photopolymer layer is immersed in boiling water for sufficient time to swell the layer and then the swollen polymer is scraped from the printing plate.