Automatic development method of photosensitive lithographic printing plate and automatic development device thereof

Abstract

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.

1 . 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 a developer activity constant, the method comprises: 
 measuring an electric conductivity of the developer at every fixed period;    replenishing a replenisher of an amount corresponding to a replenishing amount setting value due to aging at every fixed time;    replenishing a replenisher of an amount corresponding to a replenishing amount setting value due to processing in every processing of a plate having a fixed area;    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 replenishing amount setting value due to aging and the replenishing amount setting value due to processing based on a result obtained by comparing the calculated operating value of electric conductivity with the measured electric conductivity of the developer.    
     
     
         2 . 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 a developer activity constant the method comprises: 
 measuring an electric conductivity of the developer at every fixed period;    integrating a setting value of replenishing amount due to aging with a last integrating value of replenishing amount due to aging at every fixed time to obtain a new integrating value of replenishing amount due to aging;    integrating a setting value of replenishing amount due to processing with a last integrating value of replenishing amount due to processing in every processing of a plate having a fixed area to obtain a new integrating value of replenishing amount due to aging; and thereafter,    when a total sum of the new integrating value of replenishing amount due to aging and the new integrating value of replenishing amount due to processing exceeds a fixed minimum value of replenishing amount,    (a) measuring an elapsed time from a point in time of a last replenishment till this point in time and calculating an operating value of electric conductivity from the elapsed time;    (b) changing 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 operating value of electric conductivity with the measured electric conductivity value of the developer;    (c) replenishing the developer in a developing tank with a replenisher of an amount corresponding to a total sum of the new integrating value of replenishing amount due to aging and the new integrating value of replenishing amount due to processing; and    (d) initializing the new integrating value of replenishing amount due to aging and the new integrating value of replenishing amount due to processing.    
     
     
         3 . 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 a developer activity constant, the method comprises: 
 measuring an electric conductivity of the developer at every fixed period;    integrating a last setting value of replenishing amount due to aging with a last integrating value of replenishing amount due to aging at every fixed time to obtain a new integrating value of replenishing amount due to aging;    integrating a last setting value of replenishing amount due to processing with a last integrating value of replenishing amount due to processing in every processing of a plate having a fixed area to obtain a new integrating value of replenishing amount due to processing;    operating a replenishment rate due to aging which is a proportion of a replenisher due to aging in the developer in a developing tank; and thereafter,    when a total sum of the new integrating value of replenishing amount due to aging and the new integrating value of replenishing amount due to processing exceeds a fixed minimum value of replenishing amount,    (a) measuring an elapsed time from a point in time of a last replenishment till this point in time and calculating a first operating value of electric conductivity from the elapsed time;    (b) changing the last setting value of replenishing amount due to aging to a new setting value of replenishing amount due to aging; and the last setting value of replenishing amount due to processing to a new setting value of replenishing amount, based on a result obtained by comparing the first operating value of electric conductivity with the measured electric conductivity value of the developer;    (c) calculating a second integrating value of electric conductivity from the replenishment rate due to aging;    (d) changing the new setting value of replenishing amount due to aging and the new setting value of replenishing amount due to processing based on a result obtained by comparing the second operating value of electric conductivity with the electric conductivity value of the developer;    (e) replenishing a developer in the developing tank with a replenisher of an amount corresponding to a total sum of the new integrating value of replenishing amount due to aging and the new integrating value of replenishing amount due to processing; and    (f) initializing the new integrating value of replenishing amount due to aging and the new integrating value of replenishing amount due to processing.    
     
     
         4 . 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 a developer activity constant, the method comprises: 
 measuring an electric conductivity of the developer at every fixed period;    integrating a last setting value of replenishing amount due to aging with a last integrating value of replenishing amount due to aging at every fixed time to obtain a new integrating value of replenishing amount due to aging;    integrating a last setting value of replenishing amount due to processing with a last integrating value of replenishing amount due to processing in every processing of a plate having a fixed area to obtain a new integrating value of replenishing amount due to aging;    operating a displacement rate of a replenisher which is a proportion of a replenishing amount in the developer in a developing tank;    operating a replenishment rate due to aging which is a proportion of a replenisher due to aging in the developer in the developing tank; and thereafter,    when a total sum of the new integrating value of replenishing amount due to aging and the new integrating value of replenishing amount due to processing exceeds a fixed minimum value of replenishing amount,    (a) measuring an elapsed time from a point in time of a last replenishment till this point in time and calculating a first operating value of electric conductivity from the elapsed time;    (b) changing the last setting value of replenishing amount due to aging to a new setting value of replenishing amount due to aging; and the last setting value of replenishing amount due to processing to a new setting value of replenishing amount due to processing, based on a result obtained by comparing the first operating value of electric conductivity with the measured electric conductivity value of the developer;    (c) calculating a second integrating value of electric conductivity from the displacement rate of replenisher and the replenishment rate due to aging;    (d) changing the new setting value of replenishing amount due to aging and the new setting value of replenishing amount due to processing based on a result obtained by comparing the second operating value of electric conductivity with the measured electric conductivity value of the developer;    (e) replenishing the developer in the developing tank with a replenisher of an amount corresponding to a total sum of the new integrating value of replenishing amount due to aging and the new integrating value of replenishing amount due to processing; and    (f) initializing the new integrating value of replenishing amount due to aging and the new integrating value of replenishing amount due to processing.    
     
     
         5 . 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 a developer activity constant, the method comprises: 
 measuring an electric conductivity of the developer at every fixed period;    integrating a last setting value of replenishing amount due to aging with a last integrating value of replenishing amount due to aging at every fixed time to obtain a new integrating value of replenishing amount due to aging;    integrating a last setting value of replenishing amount due to processing with a last integrating value of replenishing amount due to processing in every processing of a plate having a fixed area to obtain a new integrating value of replenishing amount due to processing;    operating a displacement rate of a replenisher which is a proportion of a replenishing amount in the developer in a developing tank;    operating a replenishment rate due to aging which is a proportion of a replenisher due to aging in the developer in the developing tank; and thereafter,    when a total sum of the new integrating value of replenishing amount due to aging and the new integrating value of replenishing amount due to processing exceeds a fixed minimum value of replenishing amount,    (a) measuring an elapsed time from a point in time of a last replenishment till this point in time and calculating a first operating value of electric conductivity from the elapsed time;    (b) changing the last setting value of replenishing amount due to aging to a new setting value of replenishing amount due to aging; and the last setting value of replenishing amount due to processing to a new setting value of replenishing amount due to processing, based on a result obtained by comparing the first operating value of electric conductivity with the electric conductivity value of the developer;    (c) calculating a second integrating value of electric conductivity from the displacement rate of replenisher and the replenishment rate due to aging;    (d) changing the new setting value of replenishing amount due to aging and the new setting value of replenishing amount due to processing based on a result obtained by comparing the second operating value of electric conductivity with the electric conductivity value of the developer;    (e) when the electric conductivity value of the developer is smaller than the first integrating value of electric conductivity, replenishing a predetermined amount of replenisher, whereas when the electric conductivity value of the developer is larger than the first integrating value of electric conductivity, replenishing the developer in the developing tank with a replenisher of an amount corresponding to a total sum of the new integrating value of replenishing amount due to aging and the new integrating value of replenishing amount due to processing; and    (f) initializing the new integrating value of replenishing amount due to aging and the new integrating value of replenishing amount due to processing.    
     
     
         6 . The developer replenishing method according to  claim 2 , wherein an electric conductivity value of the developer whose activity falls within a proper range is previously calculated as a target electric conductivity value; and during a time of immediately after initiating an operation of the automatic development device until the measured electric conductivity value of the developer exceeds the target electric conductivity value, an electric conductivity of the developer is measured at every fixed period, and when the measured electric conductivity value is lower than the target electric conductivity value, the developer is replenished with a development replenisher.  
     
     
         7 . An automatic development device of photosensitive lithographic printing plate for developing a plurality of exposed photosensitive lithographic printing plates with a developer containing an electrolyte and keeping a developer activity constant, which comprises 
 a development processing section for developing the photosensitive lithographic printing plates with a developer;    an electric conductivity measurement unit for measuring an electric conductivity of the developer; and    a developer replenishing unit for replenishing the developer with a development replenisher,    wherein replenishing the developer with the development replenisher is carried out based on the developer replenishing method according to  claim 1.