Abstract:
A plasma system forms a dense, uniform coating of metallic oxide or other material on a relatively large substrate of metal foil or other composition located a substantial distance from the plasma gun so that the plasma stream covers the entire width of the substrate. A large pressure differential between the pressure inside the plasma gun and the ambient pressure outside of the plasma gun creates a shock pattern within the exiting plasma stream so as to disperse the plasma stream and maintain a high energy level therein, as well as thoroughly mixing a coating material introduced into the plasma stream within the gun. Mixing of the coating material within the plasma stream is further enhanced by introducing the coating material into the plasma stream either in liquid form or in the form of very small particles. In one arrangement, the plasma stream is delivered in a long, narrow configuration across the width of the substrate by a nozzle with a slit-like opening at the lower end of the plasma gun. In still other arrangements, a plasma stream of elongated configuration is provided by a plasma gun of elongated configuration having an elongated cathode assembly disposed within the hollow interior of an elongated anode having a nozzle-forming slot therein. Arc gas introduced into the space between the cathode and adjacent portions of the anode flows out of the slot to form a broad plume plasma stream, in conjunction with spray material introduced in powder form into the spaces between the cathode and the opposite portions of the anode along the length of the plasma gun. The cathode assembly may be of integral construction along the length of the anode, or it may be divided into plural segments disposed in spaced-apart relation along the length of the anode.
Abstract:
A method of preparing a support for a lithographic printing plate is described, which comprises roughening the support surface by laser irradiation performed under the condition that the support is placed in a liquid or in a gaseous atmosphere, thereby achieving improved stain resistance upon printing and excellent printing press life.
Abstract:
Substantial surface areas can be treated by continuously magnetically moving an electric arc around a general loop direction such as a circle, ellipse or oval and moving the surface so that the arc treats a substantial surface area. The arc treatment can be used to clean or increase surface area, or both, and a reactant or treatment agent can be brought to the arc contact site to alter the surface treated with the arc. Auxiliary treatments for the surface can precede or follow the arc treatment, or both. The invention produces very desirable surface properties including a mild roughness or matte condition suitable even for critical applications such as aluminum lithoplate. Other surface characteristics can include one or more of: capillarity, adhesion, emissivity, stable oxide, paintability, and others. Applications and advantages are believed to include lithoplate, hydrophilic heat exchanger finstock, capacitor foil, can sheet, venetian blind stock, adhesive bonded laminates and other bonded structural materials or structures, welding rod, aluminum brazing sheet, interrogatable strips for optical control instruments, enhanced, high current contacts, improved, controlled or differential friction characteristics for forming and shaping, automotive and other sheet, hot roll bonding, galvanizing and zinc coating of steel, texturing mill rolls, pretreatment for thermal spray treatments, organic coating adhesion, improved paint hiding performance, prosthetics, biohost or catalyst support and others. The process is applicable to aluminum, steel and other metals and other materials capable of carrying current sufficiently to maintain an electric arc.
Abstract:
The present invention provides a copper plating method and apparatus for a gravure cylinder in which copper plating with more uniform thickness can be provided over a full length of a gravure cylinder without causing defects such as rashes and pits irrespective of a size of the gravure cylinder, concentration of a copper plating solution can be managed automatically, a consumption amount of an additive is reduced to make it possible to perform a plating treatment within a short period of time, a power supply cost is reduced, and handling is easy with excellent visibility. A gravure cylinder in a hollow cylindrical shape is held at both ends in a longitudinal direction. The gravure cylinder is accommodated in a plating bath filled with a copper plating solution. The gravure cylinder is energized so that the gravure cylinder functions as a cathode while being rotated at a predetermined speed. A pair of anode chambers in a long box shape, in which insoluble anodes are provided upright slidably to both sides of the gravure cylinder in the plating bath and energized so as to function as an anode, are brought close to both side surfaces of the gravure cylinder at a predetermined interval. Copper plating is provided on an outer peripheral surface of the gravure cylinder.
Abstract:
This invention relates to a process for preparing printing plates which are used in offset printing. The process produces a plate which comprises a substrate film in which a thin durable hydrophilic layer has been applied thereto. In the process, the substrate film is first microroughened by pressure blasting so that the surface roughness, R.sub.A, is in the range 0.3 to 1.5 .mu.m. Subsequently, a durable, firmly adhering hydrophilic layer is applied to substrate by plasma-spraying an oxide powder with a particle size of 1 to 40 .mu.m onto the substrate. This process produces a plate whose surface is not greasy or grainy.