Abstract: A single-phase homogeneous composition for the protection of lithographic printing plate surfaces is provided which comprises an aqueous solution of(a) a hydrophilic film forming compound which is essentially cold-water soluble,(b) a hydrophilizing agent(c) a wet film forming agent,(d) a nonionic surfactant,(e) a greasing agent,and(f) one or more desensitizing salts.

Abstract: A fountain solution concentrate for introducing a catalytic agent into lithographic printing ink. The catalytic agent is formulated into a catalytic fountain solution, transported via the fountain solution to the ink and infused therein to impart desired qualities to the ink. An organic titanate compound is used as a catalytic agent in conjunction with apparatus to initiate drying for preventing ink offset and producing clean, sharp printing. The concentrate does not require the addition of alcohol.

Abstract: The dampening apparatus and method provides automatic ink/water control for a lithographic printing press by means of a hydrophylic metering roll in a pan for fountain solution which contacts an oleophylic transfer roll. The transfer and metering rolls are free wheeling friction driven rolls which are driven in substantially a one-to-one surface speed ratio by friction between the transfer roll and a dampener form roll to cause the metering roll to provide an unmetered excess of dampening fluid from the pan to a nip with the transfer roll. The dampener form roll is positively driven from the drive system for the press plate cylinder at a one-to-one surface speed ratio with the plate cylinder and is a resilient oleophylic roll having a durometer within the range of 20 to 30 durometer. The transfer roll is harder and of different diameter than the dampener form roll with a durometer in the range of from 30 to 60 durometer.

Abstract: A device for removing excess water from an aqueous emulsion of lithographic printing ink comprises a pair of rollers co-operating together to form a nip. Emulsified ink is fed to the nip and is broken down into an ink phase and an aqueous phase by the pressure exerted by the nip. The aqueous phase is displaced away from the ink phase by gas jets. The ink phase remains on the surface of one of the rollers and is removed and returned to the printing press.

Abstract: Ink is applied to a lithographic printing plate from an engraved roller provided with a plurality of cells in its surface. Ink is introduced into the cells by an inking device comprising a pressurized substantially closed ink duct defined by an axially extending sealing member contacting or close to the surface and an axially extending doctor blade in contact with the surface.

Abstract: Isopropyl alcohol is partially or completely replaced in an acid fountain solution for lithographic printing by a hydroxypropylcellulose or similar polymer with a molecular weight below 100,000 where a 30% by weight solution of the polymer has a viscosity below 4000 cps at 25.degree.. Printing quality is improved and scumming is controlled when a hydrogen peroxide degraded hydroxypropylcellulose or hydrophobically modified hydroxyethylcellulose replaces alcohol in a fountain solution.

Abstract: Printing ink vehicles including an emulsion of a mineral oil, preferably a light mineral oil; a significant amount of water; and an emulsifying agent including an amine or alkali metal salt of an oxidized hydrocarbon wax. Printing inks incorporating the vehicles include the vehicle together with a coloring agent such as a pigment.

Abstract: A method for introducing a catalytic agent to lithographic printing ink. The catalytic agent is formulated into a catalytic fountain solution, transported via the fountain solution to the ink and infused therein to impart desired qualities to the ink. An organic titanate compound is used as a catalytic agent in conjunction with apparatus to initiate drying for preventing ink offset and producing clean, sharp printing.

Abstract: A process for the offset printing of stock material in which the blanket is inked repeatedly with the printing ink so that an image having an elevated ink layer thickness is produced on the blanket. Before the transfer of the image to the stock any moisture (water) on the blanket is removed, whereafter a non-hygroscopic stock is printed in a single printing step. Consequently, a high color saturation after a single printing is produced even when transparent or opal foil is used for illuminated advertising.

Abstract: Alcohol solutions for use as fountain solutions in the printing industry are disclosed. The solutions include isopropyl alcohol in amounts of 40% to 95%, ethyl alcohol or other alcohols in amounts of 5% to 60% and ethylene diamine in an amount of 0.015% to 0.040%. The addition of a small amount of ethylene diamine markedly reduces the emission of fumes from the fountain solutions.

Abstract: A printing method and apparatus which use a sleeve-shaped printing form attached to a rotating body. The sleeve-shaped form conveniently permits the printing operation to be performed continuously and on both sides of the print carrier simultaneously. The sleeves preferably exhibit a number of process-specific functional layers. Exemplary layers are: (1) a supporting metal sleeve, (2) an intermediate metal layer for carrying the ink, and (3) a surface metal layer for carrying the water. Copper is an exemplary intermediate layer, and chromium is used as the surface metal layer.

Abstract: A fountain solution for introducing a catalytic agent to lithographic printing ink. The catalytic agent is formulated into a catalytic fountain solution, transported via the fountain solution to the ink and infused therein to impart desired qualities to the ink. An organic titanate compound is used as a catalytic agent in conjunction with apparatus to initiate drying for preventing ink offset and producing clean, sharp printing.

Abstract: A method for lithographic printing of paginal publications which comprises applying onto a flexible supporting base two or more lithographic printing plates arranged in the rotational direction of a master cylinder and to form such a structure with front and rear edge portions of the adjacent lithographic printing plates as to prevent penetration of damping solution between the supporting base and the lithographic printing plates, the portion of said structure receiving substantially no ink. This supporting base is mounted on a master cylinder of a printing machine and printing is carried out.

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 flat-bed press having a carriage (4) which includes an ink roller (7) and a blanket (5), and which is adapted to be moved on a press body frame (1) provided with an inking unit (3) at at least one end thereof, characterized in that the press body frame (1) is provided therein with a table (10) on which the materials (12) to be printed are placed, a feed head (21) having suckers (22) for retaining thereon a material (12) to be printed, and a transfer means (23) for moving the feed head (21) and carrying the material (12) to be printed which is retained on the suckers (22) to a paper bed (9).

Abstract: A system for the continuous and automatic supply of a mixture of ink and dampening fluid to a lithographic press. The ink and dampening fluid are mixed and then pumped to the press fountain. The fluid mixture is sampled downstream from the mixing location and a signal is sent to control feed of ink and dampening fluid to the mixing location to ensure that the desired ratio of ink to water is maintained.

Abstract: A composition useful for rapidly and safely effecting a fat-desensitizing treatment for litho printing plates with a high efficiency, and for providing a hydrophilic membrane having a high durability in printing operations on the surfaces of the litho printing plates, comprises (A) a phytic acid or its functional derivative; (B) a metal salt of the formula MX.sub.

Abstract: A novel dampening unit for an offset press is proposed, comprising a nozzle (20) with a discharging mouth (21) in the form of a slit directed substantially at a tangent to an outer surface of the plate (6a) and extending in the axial direction of the plate cylinder (6), which discharging mouth (21) is disposed near the plate surface. The interior of the nozzle (21) is divided into upper and lower chambers (20a, 20b) from the innermost area thereof to the discharging mouth (21) by a partition (22) extending in the direction of an air stream over the whole length of the nozzle (20). A device for generating an air stream, such as a fan (23) is disposed within the upper chamber (20a) and a device for generating a mist such as an ultrasonic generator (27) is disposed within the lower chamber (20b).

Abstract: For monitoring the condition of a universal fountain solution for planographic printing, a concentrated universal fountain solution is premixed with a color-change indicator material of predetermined characteristics such as lichen blue. The concentrated fountain solution is provided at a pH above about 3.5 and below about 4.5; the diluted fountain solution is formed by diluting such concentrated solution with water. The contamination occurring during planographic printing which is detrimental to fountain solution effectiveness and printing quality causes the pH of such diluted solution to increase. The indicator material provided initiates a change in color of the diluted fountain solution at a pH when the solution is beginning to lose effectiveness and provides an intense color change as pH increases to a level indicating that the solution should be changed in order to avoid deterioration in the desired quality of printing.

Abstract: A method of flexographic or rotogravure printing onto a plastic substrate using a water-based ink is disclosed wherein the improvement comprises adding to said ink from about 0.005 to about 5 weight percent of a low molecular weight silicone compound. The incorporation of the silicone compound provides good wetting of the substrate by the ink and results in improved printing characteristics.

Abstract: A desensitizing gum comprising an aqueous solution of water-soluble and film-forming hydroxyalkylated starch, characterized in that the degree of etherification of the hydroxyalkylated starch is 0.03 to 0.08 and the gum further contains at least one member selected from the group consisting of anionic and nonionic surfactants.

Abstract: A desensitizing gum containing water-soluble carboxy alkylated starch wherein the carboxy alkyl group number of said carboxy alkylated starch is from 0.03 to 0.5. The desensitizing gum has desensitizing ability comparable to gum arabic.

Abstract: The invention relates to a system for applying dampening fluid to the plate cylinder of printing presses which is particularly adapted to contacting continuous dampening systems. The dampening fluid applying roller is in contact with the rotating plate cylinder and there is a wiping action between the dampening fluid applying roller and the plate cylinder which loosens foreign particles from the plate cylinder so they can be removed. The dampening fluid applying roller rotates at a different speed than the plate cylinder to cause the wiping action. Preferably, the dampening fluid applying roller rotates at a slower speed than the plate cylinder. In another form of the invention an ink receptive roller is driven at the same speed as the dampening or delta roller while in contact with the dampening roller.

Abstract: An offset lithographic press, as commonly found in the newspaper industry, is provided with an airless, pulsed spray dampening system for simplified, automatic control of the ink/dampening fluid balance. The dampening system is constructed in accordance with several critical parameters, including the center-to-center nozzle spacings, nozzle to adjacent roller spacings, as well as the frequency of pulses per minute, the duration of each pulse, and the pressure of the dampening fluid. Construction of a dampening system in accordance with the critical parameters enables the press to be operated with a minimum of user intervention, and the relatively small spacing between the nozzles and the adjacent rollers is such that the dampening system can be mounted adjacent the aisles between the press units for facilitating maintenance thereon.

Abstract: A keyless inking system for lithographic printing presses wherein an ink/water mixture is contained in an ink pan having a tray portion within which an ink roller is mounted whereby ink/water mixture enters the tray portion on one side and is drawn by the ink roller to the other side of the tray in the nip between the ink roller and a celled metering roller thereby delivering an excess of the mixture to the celled metering roller, the balance of the mixture being conveyed over a weir into a reservoir for continuous mixing and recirculation back to the pan, and wherein the excess ink/water mixture on the metering roller is continuously scraped off by means of a doctor blade and wherein the metered portion of the ink/water mixture remaining in the metering roller's cells is delivered in part into the inking train of a more-or-less conventional lithographic printing press.

Abstract: An improved fountain solution and viscosity control thereof is disclosed for lithographic printing using dampening systems of the continuous type, such as a Dahlgren system. The fountain solution utilizes a viscosity imparting or thickening agent for viscosity control, such as hydroxypropylmethyl cellulose, to effect a desired viscosity. A thickened solution is prepared, and this solution is added to an aqueous solution including an ionic etch to provide a fountain solution having a viscosity of between about 20 seconds and about 22 seconds as measured in a #1 Shell cup.

Abstract: Water based fountain solutions for use in lithographic printing. The fountain solutions contain sufficient hydrogen peroxide to cause lithographic inks to dry more quickly. Typically the fountain solutions will contain about 0.005 wt. % to about 5.0 wt. % of hydrogen peroxide. The hydrogen peroxide containing fountain solutions are typically manufactured as concentrates which are diluted with water at the printing sites to form the proper strength fountain solutions required for printing. The hydrogen peroxide containing fountain solutions are used in conventional lithographic printing processes.

Abstract: A desensitizing gum for a lithographic printing plate and a gumming up process thereof are disclosed. The gum is comprised of water having dispersed therein 5 to 35 wt %, based on the total weight of the gum, of a film-forming, water-soluble compound selected from the group consisting of enzyme-decomposed dextrine and enzyme-decomposed etherified dextrine. The desensitizing gum exerts a desensitizing action on non-image areas of a lithographic printing plate and does not cause image blinding of image areas even when the plate is stored for a long period of time.

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: Lithographic fountain solution concentrates which are combined with water to form improved fountain solutions. The concentrates contain specific quantities of buffer salts resulting in improved printing process characteristics. The buffer salts are the salts of polycarboxylic acids and organic bases such as amines. The use of alcohol in the fountain solutions is eliminated or substantially reduced.

Abstract: Described herein is an improved fountain solution suitable for use in a lithographic offset printing press which solution contains a mixture of a polyol and/or glycol ether partially soluble in water and a polyol and/or glycol ether completely soluble in water.

Abstract: Lithographic fountain solution concentrates which are combined with water to form improved fountain solutions. The concentrates contain specific quantities of buffer salts resulting in improved printing process characteristics. The buffer salts are the salts of polycarboxylic acids and organic bases such as amines. The use of alcohol in the fountain solutions is eliminated or substantially reduced.

Abstract: A steel ink metering roller for use in lithographic printing having an engraved surface that has been nitride hardened followed by an oxidizing process that results in a surface with a composition of mainly Fe.sub.3 O.sub.4.

Abstract: A process for desensitizing lithographic printing plates is described. The gum for the process comprises an aqueous solution containing a film-forming starch derivative modified with polyoxyethylene or a polyoxyethylene-polyoxypropylene copolymer. The gum reduces the number of spoiled copies printed and the amount of staining on non-image areas.

Abstract: An improved method and system for properly supplying and mixing printing chemicals and liquid diluent and for supplying the resulting liquid is provided. The method and system feature the use of periodic or continuous monitoring of the ph and/or electrical conductivity level of the printing liquid in a mixing zone to regulate the flow of initial and make-up chemicals to the zone, so that the proper concentration of chemicals is maintained in the liquid. The liquid is at least periodically removed from the mixing zone and make-up diluent is at least periodically added to the mixing zone. The method can be successfully run on a batch, semi-continuous or continuous basis and the system employs an automatic electronic ph and/or electrical conductivity analyzer and signal generator to automatically control signal responsive pumps in the conduit line(s) from the chemical supply zone(s) to the mixing zone.

Abstract: Web letterpress equipment is converted to offset lithographic equipment by modification of a driven letterpress impression cylinder to receive an offset blanket, thereby producing an offset blanket cylinder. A letterpress plate cylinder is modified to become an offset plate cylinder with accompanying offset inking and dampening equipment. In one embodiment, a driven letterpress plate cylinder of a color hump is packed to become an offset impression cylinder cooperating with the offset blanket cylinder. In a second embodiment, the letterpress plate cylinder of the color hump is modified to an offset color plate cylinder and a driven offset impression cylinder is added to cooperate with the offset printed on one side of a web. When used in combination with similarly converted letterpress plate, impression and color hump plate cylinders, at least three colors may be offset printed on one side of a web or multiple colors printed on opposite sides thereof.

Abstract: A novel ink formulation, especially useful in Driography printing, is disclosed. The ink formulation comprises a basic planographic printing ink vehicle, a pigment, a modifying varnish and a flow control agent to provide an ink, especially suitable for use in Driography, which exhibits desirable hangling-viscosities under ambient conditions, improved rheological properties under severe press-operating conditions, and provides printings having sharp delineation, fidelity and excellent reproducibility in depth of color tones in long press runs. The basic printing ink vehicle may be a vehicle designed for either sheet-fed or heat-set printing systems. The novel ink formulation is designed to have a high viscosity and avoid becoming pseudoplastic in its behavior at higher press temperatures, which generally can range from about 85.degree. F. to 125.degree. F., and preferably, avoids becoming pseudoplastic at temperatures up to about 140.degree. F. or more.

Abstract: Printing characteristics such as ink receptivity and printing endurance of a lithographic printing plate which utilizes as ink receptive areas the photographically formed silver or silver halide image can be improved by treating said printing plate in the presence of a polymer compound containing in its principal and/or side chain an aromatic nucleus bearing a hydrophilic substituent group, said printing plate containing in at least one of its constitutive layers as hydrophilic high molecular weight-binder.

Abstract: Water and oil base ink are delivered to lithographic plates as a single liquid, a mixture of water and ink, wherein the water is in the form of fine droplets dispersed in the ink. Preferably also, lithographic concentrate is added to the mixture as part of the water content. During a printing run the mixture is automatically resupplied to the printing machine by a level sensor that controls the amount of ink and water and by a pH sensor that controls the concentrate percentage. The proportion of ink and water is controlled by a moisture sensor. The thickness of the film of mixture delivered to the lithographic plate is controlled by a density sensor. A viscosity sensor controls the agitation of the mixture. As few as three rollers are required to deliver the ink-water-concentrate dispersion from a fountain to a lithographic plate.

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: Selective reduction in ink tackiness resulting in better ink transfer with less print through better image reproduction fidelity, less plate wear, less waste of paper, and less linting may be accomplished by selective warming of the image areas on the printing plates prior to application.

Abstract: Method for lithographic printing wherein a lithographic printing plate having oleophilic and hydrophilic areas on the printing surface of the plate is contacted with ink and an aqueous fountain solution during printing. An aqueous solution comprising an enzyme is used as the fountain solution.

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: A method for treating imaged lithographic printing plates with a solution comprising (1) water, (2) an active polymer component for rendering non-image areas of a lithographic printing plate hydrophilic, comprised of a polyacrylamide-based polymer or copolymer or a blend of polyacrylamide and polyacrylic acid, or the like, said polymer or copolymer or blend having an average molecular weight of from about 5,000 to about 10.sup.

Abstract: A liquid composition for treating surface of lithographic printing plates, especially etching liquid and dampening liquid which essentially consists of (a) phosphoric acids, (b) nitric acid or salts thereof and (c) nitrous acid or salts thereof and which has all characteristics required for treating liquids used for offset printing, has excellent ability of rendering the non-image areas oil-unreceptive and has rust resistance for all metals. This composition may additionally contain aminopolycarboxylates, polyol compounds and inorganic fine particles.

Abstract: This invention is directed to a composition useful for making a fountain solution for lithographic printing operations which comprises trisodium phosphate, sodium metasilicate, tetrapotassium pyrophosphate, a nonionic detergent which is a condensation product of ethylene oxide with a dialkylphenol, an alkylamine or an aliphatic alcohol, and dialkylpolysiloxane. The invention is further directed to a method for making such a fountain solution which comprises combining any of the compositions of the invention with water.

Abstract: Aqueous solutions are provided for treating image-bearing lithographic plates.

Abstract: An aqueous nonblinding lithographic plate finisher suitable for machine operation is provided which comprises an essentially cold-water soluble dextrin or polyvinyl pyrrolidone as hydrophilic polymer with a nonionic surfactant or mixture thereof having a hydrophile-lipophile balance between about 12 and 18, a humectant and a salt.

Abstract: Aqueous solutions are provided for treating image-bearing lithographic plates.

Abstract: An offset printing system and method wherein a plate cylinder, a blanket cylinder and ink applying means are arranged in cooperative relationship. The ink applying means applies ink to a plate removably carried by the plate cylinder and the ink applied to the plate is transferred as an image to an image receiving surface of a blanket secured to the blanket cylinder and having an image receiving surface comprising a solid fluoroelastomer. In the disclosed embodiment, the fluoroelastomer is a copolymer of vinylidene fluoride and hexafluoropropylene of a grade which remains solid and deforms elastically at temperatures in excess of 150.degree. F. The fluoroelastomer has a specific gravity between about 1.82 and 1.86 and the ink applying means may also be provided with a surface comprising a fluoroelastomer which remains solid and deforms elastically at temperatures in excess of 150.degree. F.