A lithographic printing plate support

摘要

A method for making a lithographic printing plate support is disclosed comprising the steps of: (i) providing an aluminum support; (ii) treating said support in an aqueous solution; (iii) graining said treated support in an electrolyte solution by applying an alternating voltage thereby inducing a local current density J;
characterized in that said local current density J at time t fulfilles the following equation : J t ‰ a + b �¢ Q t for t = o to t = t f
and wherein
- Q(t) is the integrated value of the absolute value of the local current density at time t: Q t = ˆ« 0 t J Ä �¢ d �¢ Ä
- a is equal to 5
- b is equal to 10
- and t f is the time necessary to obtain a value of Q(t) equal to 50 C/dm 2 .