Lightened offset plates, preparation and use thereof

A plate for use in wet offset printing, comprising at its surface ink-accepting surfaces corresponding to patterns to be printed;

• at least part of said ink-accepting surfaces being lightened, i.e. including small non ink-accepting lightening surfaces, characterized in that over at least part of said lightened ink-accepting surfaces, said small non ink-accepting lightening surfaces are distributed in at least two groups:
• a first group of small non ink-accepting surfaces with an area (areas) sufficient to be effective per se and in a quantity sufficient to lighten the ink-accepting surface(s) involved in lightening by at least 4%;
• and
• a second group of small non ink-accepting surfaces, not effective per se because their area(s) is (are) too small;
• the mean area of said small non ink-accepting surfaces of said second group in general being less than ⅔ of the mean area of said small non ink-accepting surfaces of said first group;
• said small non ink-accepting surfaces of said first and second groups being distributed so as to minimize, advantageously avoid, any moiré effects.