Abstract: A controller for a moisture adjusting device of the present invention reads out a target moisture content set in advance in a data table in accordance with a type of a planographic printing plate; determines, every predetermined control period, a moisture content of an overcoat layer (measured moisture content) based on a measured signal SW; and calculates a difference (deviation) between the measured moisture content and the target moisture content. For example, if the measured moisture content of the overcoat layer is lower than the target moisture content, the controller sets an adjusted moisture content which is higher than the measured moisture content and controls the humidity and the temperature within a humidity conditioning zone so that an interposing paper web (protective sheet material) attains the adjusted moisture content within the humidity conditioning zone.

Abstract: A controller for a moisture adjusting device of the present invention reads out a target moisture content set in advance in a data table in accordance with a type of a planographic printing plate; determines, every predetermined control period, a moisture content of an overcoat layer (measured moisture content) based on a measured signal SW; and calculates a difference (deviation) between the measured moisture content and the target moisture content. For example, if the measured moisture content of the overcoat layer is lower than the target moisture content, the controller sets an adjusted moisture content which is higher than the measured moisture content and controls the humidity and the temperature within a humidity conditioning zone so that an interposing paper web (protective sheet material) attains the adjusted moisture content within the humidity conditioning zone.

Abstract: A controller for a moisture adjusting device of the present invention reads out a target moisture content set in advance in a data table in accordance with a type of a planographic printing plate; determines, every predetermined control period, a moisture content of an overcoat layer (measured moisture content) based on a measured signal SW; and calculates a difference (deviation) between the measured moisture content and the target moisture content. For example, if the measured moisture content of the overcoat layer is lower than the target moisture content, the controller sets an adjusted moisture content which is higher than the measured moisture content and controls the humidity and the temperature within a humidity conditioning zone so that an interposing paper web (protective sheet material) attains the adjusted moisture content within the humidity conditioning zone.

Abstract: In the electrolytic treatment, an acid concentration meter measures the concentration of hydrochloric acid. The difference from a measured value PVb to a preset value SVb of the concentration of hydrychloric acid is larger than preset value e, hydrochloric acid is fed out from an acid feeding section. The aluminum concentration meter measures the concentration of the aluminum chloride. A water feed cycle is calculated from a measured value PVa and a preset value SVa of the concentration of hydrochloric acid, and a total value of the electrolytic current I generated by a power source section. At every water feed cycle, a water feeding section feeds water to add to the electrolytic solution.

Abstract: A controller for a moisture adjusting device of the present invention reads out a target moisture content set in advance in a data table in accordance with a type of a planographic printing plate; determines, every predetermined control period, a moisture content of an overcoat layer (measured moisture content) based on a measured signal SW; and calculates a difference (deviation) between the measured moisture content and the target moisture content. For example, if the measured moisture content of the overcoat layer is lower than the target moisture content, the controller sets an adjusted moisture content which is higher than the measured moisture content and controls the humidity and the temperature within a humidity conditioning zone so that an interposing paper web (protective sheet material) attains the adjusted moisture content within the humidity conditioning zone.

Abstract: A method of splicing together metal webs for use in planography with the ends thereof being butted or lapped against each other. In the metal web splicing method, the ends of the metal webs are spliced together in a butted manner, the spliced portion thereof is welded, and the welded spliced portion is rolled. According to the splicing method, there is no level difference in the welded spliced portion, which eliminates the possibility of the spliced metal webs being broken during the movement thereof and also has no adverse effect on the coating process for the spliced metal webs.

Abstract: A method of splicing together metal webs for use in planography with the ends thereof being butted or lapped against each other. In the metal web splicing method, the ends of the metal webs are spliced together in a butted manner, the splice portion thereof is welded, and the welded splice portion is rolled. According to the splicing method, there is left no level difference in the welded splice portion, which eliminates the possibility of the spliced metal webs being broken during the movement thereof and also has no ill effect on the coating process for the spliced metal webs.

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: A method of continuously electrolytically treating a metal web in an electrolytic liquid using an alternating waveform current via a pair of main electrodes such that the surface of the metal web experiences both an anode reaction and a cathode reaction. The ratio of the current value contributing to the anode reaction acting on the surface of the metal web and the current value of the cathode reaction acting on the surface of the metal web is controlled by shunting a portion of the supplied current to an auxiliary electrode, which is separated from the main electrodes, as a direct current.

Abstract: The processing supports for lithographic printing plate is improved by an induction heating method while chemically and/or eldctric-chemically surface-treating the metal sheet or web to affect the surface roughness thereof.