Method and apparatus for producing sleeve printing plate

A method for producing a sleeve printing plate which is attached to a cylinder of a printing apparatus by using a laser processing machine which is provided with a sleeve element assembly-supporting unit having a rotating drum capable of attaching a cylindrical sleeve element assembly to an outer circumferential face thereof and a pivot supporting portion for supporting the rotating drum so as to rotate, and a laser beam irradiating unit which irradiates a laser beam to the sleeve element assembly attached to the rotating drum,

• the method for producing a sleeve printing plate comprising:
• a notch forming step in which the laser beam is irradiated to the sleeve element assembly while rotating the sleeve element assembly attached to the rotating drum, thereby forming a positioning notch which is engaged with a guide pin erected on the cylinder;
• and
• an image pattern forming step in which the laser beam is irradiated to the sleeve element assembly while rotating the sleeve element assembly attached to the same rotating drum as that of the notch forming step is rotated, thereby forming an image pattern to be printed on a work piece.

An apparatus for producing a sleeve printing plate which is provided with a positioning notch to be engaged with a guide pin erected on a cylinder of a printing apparatus and an image pattern to be printed on a work piece and which is attached to the cylinder,

• the apparatus for producing a sleeve printing plate comprising:
• a sleeve element assembly-supporting unit which has a rotating drum capable of attaching a cylindrical sleeve element assembly to an outer circumferential face thereof and a pivot supporting portion for supporting the rotating drum so as to rotate;
• a laser beam irradiating unit which irradiates a laser beam to the sleeve element assembly attached to the rotating drum while rotating the sleeve element assembly, thereby forming the notch and the image pattern on the sleeve element assembly;
• and
• a control unit for controlling the rotating drum and the laser beam irradiating unit;
• wherein
• the control unit is provided with a storage unit which stores first image data indicating a position of the sleeve element assembly on which the notch is to be formed and a shape of the notch as well as second image data indicating a position of the sleeve element assembly on which the image pattern is to be formed and a shape of the image pattern and
• an energy density adjusting unit which adjusts the energy density of the laser beam in forming the notch on the basis of the first image data and in forming the image pattern on the basis of the second image data.