| 摘要 |
PURPOSE: To prevent ink from becoming stuck and improve brush contamination resistance by specifying the average pitch, average diameter and average surface roughness of honeycomb pits which are stacked unevenly in the process to roughen the surface of an aluminum support. CONSTITUTION: A pretreatment is performed using a DC voltage in an etching process using an aqueous acid or alkali solution, to remove oil and a contaminated oxidized film. Next, the surface is roughened electrochemically using a DC voltage in an aqueous acid solution, and thereby honeycomb pits are formed to form a plateau part which is equal to 15 to 60% of the surface. In addition, the smut component is removed by dissolving the edge of the plateau part, and further, the plateau part is reduced to less than 10%. The honeycomb pits are stacked over the other to improve the resistance to contamination, brush fouling and print wear and greasing. The honeycomb pits with an average diameter of 0.1 to 2μm are formed in an unevenly stacked manner at an average pitch of 1 to 80μm. The average surface roughness is 0.3 to 1.5μm. |
