Abstract: Disclosed herein are a method and apparatus for efficiently processing workpieces which are developed using a liquid developer. According to the invention a first set of workpieces is obtained from an imaging station, a second set of workpieces is obtained from a workpiece collection device, and the workpieces from the first and second sets are aligned in a contiguous arrangement, with the workpieces from the first set preferably being interspersed with those from the second set. Developer is then applied to the group of contiguous workpleces, thereby reducing the amount of overrun or overspray of developer that would otherwise result from individual processing of workpieces. The invention is particularly well-suited for use in preparing lithographic printing plates.

Abstract: The invention relates to the application of a uniform film of a fluid to the surface of a flat workpiece as it is being conveyed through a workstation. The invention is specifically directed to the development of lithographic printing plates and comprises the application of the thin film of developer solution to each plate in a controlled manner using a wire-wound coating device and a unique manner of metering and feeding fresh fluid to the wire-wound device. Specifically, the fluid is gently fed onto the wire-wound device by simple volumetric displacement and overflow from the inside of a hollow tube onto the wire and the flow is controlled by sensing the beginning and end of each workpiece or plate. The hollow tube may be the wire-wound component or it may be a tube mounted above the wire-wound component. The spent developer is rinsed and sent to waste. According to the invention, only fresh developer solution is applied at a uniform film thickness, thereby achieving uniform image development.

Abstract: A negative-working lithographic printing plate has a coating which is imaged by heating an area of the coating with an infrared laser and actinically reacting the coating in the heated area with ultraviolet or visible radiation. The coating contains an infrared absorber but the coating is not imageable by infrared radiation or by the heat generated. The imaging time is reduced since the actinic reaction rate is increased at the elevated temperature.

Abstract: The invention is directed to the development of lithographic printing plates and comprises the application of a thin, quiescent film of developer solution to each plate in a controlled manner using, for example, a wire-wound coating device or an ink-jet type head. A feature of this quiescence is that the developer fluid is applied uniformly with self-leveling over the plate at the required thickness. In the preferred embodiment the fluid is gently fed onto the wire-wound device by simple volumetric displacement and overflow from the inside of a hollow tube onto the wire, and the flow is controlled by sensing the beginning and end of each plate.

Abstract: The invention is directed to the development of lithographic printing plates by the application of a thin film of developer solution to each plate in a controlled manner using a wire-wound coating device that resists wetting-out of the solution. The exposed surface of the wire-wound coating device has a surface energy of no more than 24 dynes/cm, preferably less than about 20 dynes/cm, which can be achieved, for example by PTFE or FEP. The fluid is gently fed onto the wire-wound device by simple volumetric displacement.

Abstract: The invention relates to the development of lithographic printing plates and comprises the application of a thin film of developer solution to each plate in a controlled manner using a jetting printhead. Sensors and control means activate and deactivate the jetting printhead in response to the presence or absence of a plate. The developer is allowed to dwell on the plate as it is conveyed across a support structure for a sufficient time to allow for percolation into and/or dissolution of the soluble areas of the coating and is then washed off and sent to waste.

Abstract: The invention relates to the application of a uniform film of a fluid to the surface of a flat workpiece as it is being conveyed through a workstation. The invention is specifically directed to the development of lithographic printing plates and comprises the application of the thin film of developer solution to each plate in a controlled manner using a wire-wound coating device and a unique manner of metering and feeding fresh fluid to the wire-wound device. Specifically, the fluid is gently fed onto the wire-wound device by simple volumetric displacement and overflow from the inside of a hollow tube onto the wire and the flow is controlled by sensing the beginning and end of each workpiece or plate. The hollow tube may be the wire-wound component or it may be a tube mounted above the wire-wound component.

Abstract: A lithographic printing plate substrate web is brush grained with some of the brushes having the bristles moving over the web along a first track and some additional brushes having the bristles moving over the web along a second track at an angle of at least 5° to the first track. Some of the brushes may have the axis of rotation perpendicular to the direction of movement of the web in the conventional manner and at least one additional brush having the axis of rotation at an angle to the direction of movement of the web. There may be a plurality of such additional brushes, usually two, with the additional brushes being angled with respect to each other. In one embodiment, the bristles of the additional brush track over the web in a direction perpendicular to the web movement. Subsequent to brush graining, the brush grained surface is electrochemically grained.

Abstract: The invention relates to the development of lithographic printing plates and comprises the application of a thin film of developer solution to each plate in a controlled manner using a jetting printhead which scans the plate to apply the developer solution as the plate is conveyed under the jetting printhead. Sensors and control means activate and deactivate the scanning jetting printhead in response to the presence or absence of a plate. The developer is allowed to dwell on the plate as it is conveyed across a support structure for a sufficient time to allow for percolation into and/or dissolution of the soluble areas of the coating and is then washed off and sent to waste.

Abstract: A lithographic printing plate has a hydrophilic substrate and an oleophilic coating. The plate is simultaneously imaged and developed by applying a solvent for the coating in an image-wise pattern using a jet printer. The oleophilic coating is thereby removed in those areas where the solvent has been jetted exposing the hydrophilic substrate and leaving the residual oleophilic coating in the form of the desired positive image. Because the jetting of the solvent in the image-wise pattern may not apply solvent at the leading and trailing ends of the plate, a strip of solvent is applied to these ends by a separate applicator. Also, separate applicators may apply the solvent to the side edges of the plate. The residual oleophilic coating may be post treated to insolubilize and/or harden the image.

Abstract: A lithographic printing plate has a hydrophilic substrate and an oleophilic coating. The plate is simultaneously imaged and developed by applying a solvent for the coating in an image-wise pattern using an ink jet printer. The oleophilic coating is thereby removed in those areas where the solvent has been jetted exposing the hydrophilic substrate and leaving the residual oleophilic coating in the form of the desired positive image. The residual oleophilic coating may be post treated to insolubilize and/or harden the image.

Abstract: A lithographic printing plate substrate web is brush grained with some of the brushes having the bristles moving over the web along a first track and some additional brushes having the bristles moving over the web along a second track at an angle of at least 5° to the first track. Some of the brushes may have the axis of rotation perpendicular to the direction of movement of the web in the conventional manner and at least one additional brush having the axis of rotation at an angle to the direction of movement of the web. There may be a plurality of such additional brushes, usually two, with the additional brushes being angled with respect to each other. In one embodiment, the bristles of the additional brush track over the web in a direction perpendicular to the web movement.

Abstract: A lithographic printing plate substrate web is brush grained with some of the brushes having the bristles moving over the web along a first track and some additional brushes having the bristles moving over the web along a second track at an angle of at least 5° to the first track. Some of the brushes may have the axis of rotation perpendicular to the direction of movement of the web in the conventional manner and at least one additional brush having the axis of rotation at an angle to the direction of movement of the web. There may be a plurality of such additional brushes, usually two, with the additional brushes being angled with respect to each other. In one embodiment, the bristles of the additional brush track over the web in a direction perpendicular to the web movement.

Abstract: A method and apparatus for conveying a thin, planar, flexible work piece through a work station with the work piece being held flat as it is conveyed. Specifically, a method and apparatus for developing an imaged coating on a lithographic printing plate involves the application of a thin film of developer solution to the imaged coating and allowing time for the dissolution to take place as the plate is conveyed through the developer across a flat horizontal platen. The spent developer solution is then removed and discarded to waste. Therefore, fresh developer solution of the proper composition is always being used to develop each plate. A film of water between the plate and the conveyor belt holds the plate in position and flat on the conveyor. The fresh developer solution is stored and delivered out of contact with the atmosphere to prevent atmospheric-caused degradation.

Abstract: A negative-working lithographic printing plate has a coating which is imaged by heating an area of the coating with an infrared laser and actinically reacting the coating in the heated area with ultraviolet or visible radiation. The coating contains an infrared absorber but the coating is not imageable by infrared radiation or by the heat generated. The imaging time is reduced since the actinic reaction rate is increased at the elevated temperature.

Abstract: A coated imageable semiconductor is imaged by heating an area of the coating with an infrared laser and reacting the coating in the heated area with ultraviolet or visible radiation. The coating can be either positive working or negative working. The modulated radiation may either be the ultraviolet/visible radiation or the infrared radiation and the radiation spots are superimposed or the ultraviolet/visible spot may closely trail the infrared spot. The imaging time is reduced since the reaction rate is increased at the elevated temperature.

Abstract: Certain types of lithographic printing plates are activated by preheating while certain other types are post heated to harden the coating. A platen having a large mass compared to the mass of a printing plate is heated and maintained in the exact temperature range to which the printing plate is to be heated. A printing plate is brought into heat exchange contact with the platen for the period of time required to heat the printing plate to the temperature of the platen. The printing plate may be heated while resting in a fixed position on the platen or while the printing plate is carried over the platen by a continuous thin metal conveyor belt in intimate contact with both the platen and printing plate.

Abstract: A catalyst structure is formed by forging catalyst support particles from a slurry into the surface of a metal substrate such that the particles protrude from the surface and are permanently fixed into the surface. The forging is accomplished by engaging rollers with the surface as it passes through the slurry to press the particles into the surface. The rollers may be brush rollers, fabric rollers or solid rollers. The particles may be any particles which are capable of having a catalyst deposited thereon and which are hard enough to forge into the metal substrate. The catalyst material is then deposited onto the catalyst support particles.

Abstract: A substrate metal such as aluminum, usually in the form of a web, is anodized to form a porous oxide coating. A catalytic metal is then electrolytically deposited into the base of the pores preferably using an AC current. A portion of the oxide coating is then stripped away to expose the deposited catalytic metal at the surface of the remaining oxide layer. Alternately, a generally non-catalytic base metal may first be deposited followed by the deposition of the catalyst metal within the pores over the base metal. Further alternatives include stripping the oxide down to the base metal and then depositing the catalyst metal on the surface, further anodizing to form additional oxide between the deposited metal and the substrate, and enlarging the cross section of the base of the pores prior to the deposition of the metal.

Abstract: An elongated web of lithographic printing plate stock is intermittently fed to the drum of an external drum imaging device. The web is then cut to form the trailing end of an individual printing plate either before or after the leading end is clamped to the drum. The drum is then rotated such that the plate is wrapped around the drum and the trailing end is clamped to the drum.