摘要:
A developer replenishing method of an automatic development device of photosensitive lithographic printing plate including developing a plurality of exposed photosensitive lithographic printing plates with a developer containing an electrolyte and keeping the developer activity constant, which includes measuring an electric conductivity of the developer in every predetermined fixed period; providing a predetermined setting value of replenishing amount due to aging in every fixed time; providing a predetermined setting value of replenishing amount due to processing in every processing of a plate having a fixed area; calculating a replenishing amount due to aging based on the replenishing amount setting value due to aging; calculating a replenishing amount due to processing based on the replenishing amount setting value due to processing; calculating an operating value of electric conductivity from the replenishing amount due to aging and the replenishing amount due to processing; and increasing or decreasing the setting value of replenishing amount due to aging and the setting value of replenishing amount due to processing based on a result obtained by comparing the calculated operating value of electric conductivity with the electric conductivity of the developer.
摘要:
An automatic developing apparatus for photosensitive lithographic printing plates, includes a development vessel storing a plate developer and a replenishing apparatus for replenishing a predetermined amount of development replenisher in accordance with an electric conductance of the plate developer. The replenishing apparatus includes: an electric conductance sensor detecting the electric conductance of the plate developer; a delivery device delivering the development replenisher into the development vessel; a timer detecting an elapsed time from replenishment of the development replenisher; and a control device for setting a reference electric conductance and for controlling the delivery device to replenish the development replenisher when the detected electric conductance has fallen below the set reference electric conductance. The control device calculates a carbon dioxide exhaustion replenisher ratio for replenishing the development replenisher in accordance with the elapsed time and the predetermined amount of the development replenisher. The automatic developing apparatus is capable of maintaining the activity of the plate developer in a good condition over a long period of time by the ratio between the plate processing exhaustion and the carbon dioxide exhaustion.
摘要:
A development replenisher replenishment method in an automatic developing machine for a photosensitive lithographic printing plate precursor, the method comprising: developing a plurality of sheets of exposed photosensitive lithographic printing plate precursors with a developer containing an electrolyte while replenishing a development replenisher to keep a developer activity constant, wherein an electric conductivity of the developer is measured every constant period; a development replenisher is replenished every constant time as a time lapse replenisher in an amount based on a set value of a time lapse replenishment rate; a development replenisher is replenished every processing of a constant area of a photosensitive lithographic printing plate precursor(s) as a processing replenisher in an amount based on a set value of a processing replenishment rate; a calculated value of an electric conductivity is calculated from an amount of the time lapse replenisher and an amount of the processing replenisher; and when a set value of a replenishment system indicates an electric conductivity system, the set value of the time lapse replenishment rate and the set value of the processing replenishment rate are increased or decreased according to a result of a comparison of the calculated value of the electric conductivity with the measured value of the electric conductivity of the developer, or when a set value of a replenishment system does not indicate an electric conductivity system, the set value of the time lapse replenishment rate and the set value of the processing replenishment rate are not increased or decreased.
摘要:
A method for replenishing a development replenisher in an automatic developing machine for a photosensitive lithographic printing plate precursor, wherein a value of an electric conductivity of a developer obtained by measuring an electric conductivity is compared with a reference value, and a development replenisher is replenished to the developer when the value of the developer is lower than the reference value, the method comprising: using a reference value of an electric conductivity optimal for a high resolution image as the reference value when developing a precursor having an exposed high resolution image in which an output datum of 50% area ratio is 210 lpi or more in terms of a peripheral length of an image area in an image unit that constitutes a gradation of a screen image: and changing the reference value to an ordinary reference value when developing a precursor not having a high resolution image.
摘要:
An automatic processing method by developing a plural number of exposed photosensitive lithographic printing plates with a developer, which comprises the previously calculating step, the measuring step and the replenishing step as defined herein, wherein during a period from immediately after start of operation of an automatic processing apparatus until the measured electric conductivity value of the developer exceeds the target electric conductivity value, the target electric conductivity value is corrected using a first operation expression as previously defined for every replenishment of the developer replenisher; and after the measured electric conductivity value of the developer first exceeds the target electric conductivity value after start of operation of the automatic processing apparatus, the target electric conductivity value is corrected using a second operation expression for every replenishment of the developer replenisher.
摘要:
In order to compensate the reduction of a developing activity during working and/or stopped period, a replenisher and/or a diluent is added to the developer according to predetermined replenishing conditions, and also in order to compensate the reduction of the developing activity caused by processing photosensitive materials, the replenisher and/or the diluent is added to the developer. Then, in cases where the electric conductivity of the thus replenished developer exceeds a predetermined target value, the diluent is replenished to the developer tank until the electric conductivity of the developer falls below the target value.
摘要:
A method for developing a material having a photosensitive resin composition or a photosensitive lithographic printing original plate is disclosed, comprising developing a material having a plurality of photosensitive resin composition sheets in sequence with a developer or developing a photosensitive lithographic printing plate precursor with an alkaline developer, wherein the activity of developer is maintained by detecting the exhaustion of developer occurring with the development and passing a current between two electrodes through a developer according to the degree of exhaustion detected. Also disclosed is a development processing apparatus for use in the development of the material having a photosensitive resin composition or the photosensitive lithographic printing plate precursor.
摘要:
A heating apparatus according to the present invention has a heating portion 102 for conveying a printing plate 120 incorporating a metal support plate, on which a photosensitive layer is formed, into a hot atmosphere radiated from a heat source; upstream conveying rollers and downstream conveying rollers 10, which are disposed upstream and downstream of the heating portion and are structured to hold the printing plate 120 from upper positions and lower positions to convey the support member. In the heating apparatus, at least one of the rollers, which constitute the downstream conveying rollers, has a drive shaft 11 and a central hole through which the drive shaft is inserted. The heating apparatus further incorporates a plurality of disc-like members 12 rotatively joined to the drive shaft and friction members for exerting frictional resistance on the disc-like members which are rotated with respect to the drive shaft are provided. The disc-like members 12 are structured to prevent occurrence of deformation of the printing plate due to expansion or permit passage without crushing of the deformed portion formed due to the expansion.