Fuji Photo Film Company, Limited

Nippon Light Metal Company, Ltd.

Kazutaka Oda

Tsutomu Kakei

Hisao Ohba

Masahiro Takahashi

Azusa Ohashi

Yoshio Okishi

Akio Uesugi

Hirokazu Sakaki

Akira Shirai

Toshio Hagiwara

Teruo Miyashita

Akira Morita

Yukio Yabuta

Yoshio Kon

A support for a lithographic plate produced by a process which comprises:

Grain structure for lithographic printing plate supports

A process for producing a support for a lithographic printing plate is described, which comprises jetting a high-pressure liquid from at least one nozzle at a high rate, joining the jetted stream with a slurry containing a fine abrasive powder having a specific gravity of not less than 2.5 and having a sharp-angled tip having a radius of not more than 20 .mu.m, said slurry being spouted from at least one spout, directing the resulting mixed stream to strike against a surface of a metal sheet to carry out first graining, and modifying the first roughness thus formed on the metal sheet by brush graining to form a second roughness. Lithographic printing plates produced by using the resulting support are free from stain formation during printing and exhibit satisfactory printing durability.

Process for producing support for lithographic printing plate

An apparatus for continuously drying a coating layer on a web includes a deflecting and heating roller which deflects the web having the coating and traveling continuously in a drying chamber. The deflecting and heating roller is disposed so as to be capable of varying its position for deflecting the web so that the length of the web to stay in the drying chamber can be varied and adjusted. Gas-flow supply means is provied for supplying a gas flow to the coating of the web traveling in the drying chamber.

Apparatus for continuously drying coating layer on web

A process for producing a support for a lithographic printing plate is disclosed, comprising mechanically graining a sheet for the support with abrasive grains which have sharp-angled tips having a radius of not more than 20 .mu.m. The process is suitable for mass production, and the lithographic printing plate produced from the resulting support is excellent in stain-resistance and printing durability.

A cylindrical electrolytic treatment vessel, containing an electrolyte and serving as one electrode, rotatably mounts in a concentric manner a cylindrical rotary body which is mounted for rotation horizontally about its axis. The cylindrical rotary body has enlarged diameter portions at opposite axial ends and at least the peripheral surfaces of the enlarged diameter portions are made of an electrically insolative material. The rotor body has a central smaller diameter portion intermediate of the enlarged diameter portions which is formed of metal and constitutes a second electrode. Electricity is applied between the treatment vessel and the cylindrical rotor body electrode. The metal web is rotatably supported along opposed side edge portions of the web by the electrically insulative surfaces of the enlarged diameter portions of the body so that continuous electrolytic treatment is effected to the metal web as it passes through the electrolyte.

Device for performing continuous electrolytic treatment on a metal web

A method and apparatus for electrolytic treatment employing graphite electrodes wherein an asymmetrical waveform alternating current is applied to the electrodes to subject a metal web to a continuous electrolytic treatment. A graphite electrode in a treatment section is arranged confronting the metal web. Two graphite electrodes in current supply sections are arranged respectively upstream and downstream of the graphite electrode in the treatment section relative to a direction of movement of the metal web. Two auxiliary anode electrodes in the current supply sections are arranged respectively upstream and downstream of the two graphite electrodes in current supply sections. A part of an asymmetrical alternating waveform current is supplied to the auxiliary anode electrodes so that a current causing a cathode reaction on the surfaces of the graphite electrodes is made larger than a current causing an anode reaction thereon.

Method and apparatus for electrolytic treatment

A method of electrolytic treatment on the surface of metal web, such as may be employed to fabricate offset printing plates supports, in which the rate of consumption of graphite electrodes used with the process is remarkably reduced. A current having asymmetric positive and negative half cycles is applied between graphite electrodes disposed in a main cell. A portion of the current of the half cycle having the larger average value is applied to an auxiliary anode electrodes provided in an independent auxiliary cell separated from the graphite electrodes. The auxiliary electrode is made of an insoluble material. By making the current density for anode reaction on the surfaces of the graphite electrodes smaller than the current density for cathode reaction on the surfaces of the graphite electrodes, the consumption rate of the graphite electrodes is greatly reduced.

Method of electrolytic treatment on the surface of metal web

A web conveying method and apparatus in which a metal web is maintained substantially parallel to an adjacent electrode despite fluctuations in the flow of an electrolytic solution in which the web is immersed. A guide plate is disposed adjacent the web on the side thereof opposite the electrode. A plurality of through-holes are formed in the guide plate which are evenly distributed thereon. Due to the flow of solution through the guide plate, a static pressure is applied to the web which maintains it substantially parallel at all times to the electrode.

Web conveying method

A support for a lithographic plate and process for producing a support for such a plate are described, which process comprises:

Supports for lithographic printing plates and process for producing the

Web conveying method and apparatus

A method for preparing a support for a planographic printing plate using an electrolytic surface treatment of an aluminum plate is disclosed, wherein an alternating charge voltage is applied to the aluminum plate in an acidic electrolyzing bath, and the wave form representing the voltage includes an intermission of zero voltage in at least one of the anode or the cathode phases, and is such that the electric quantity for the anode phase is larger than the electric quantity for the cathode phase.

Method for preparing a support for a lithographic printing plate

A light-sensitive printing plate with a coating layer with an uneven pattern removable during development provided on the surface thereof, which can be brought into intimate contact with an original image in a short period of time by vacuum adhesion. The light-sensitive printing plate is produced by taking up a coating solution from a coating solution pan by a gravure roll, scraping away excess coating solution adhering to the gravure roll by a doctor blade, transferring the coating solution still retained on the gravure roll to a coating roll made of rubber with a fine uneven pattern on the surface thereof which is turning in the same direction and at the same speed as the gravure roll, and transferring the coating solution thus transferred to the coating roll to a support running at the same speed and in the same direction as the coating roll.

Light-sensitive printing plates with discontinuous over-coating

A method for electrolytically graining the surface of an aluminum plate which comprises passing an alternating current through the aluminum plate in an acidic electrolyte so that

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Shizuoka, Japan

Kazutaka Oda