Patent ID: 7883833

Claim:
A method of providing a lithographic printing plate comprising: developing an imagewise exposed positive-working imageable element comprising a hydrophilic aluminum-containing substrate with an alkali silicate-containing developer composition having a pH of at least 12 and a conductivity of from about 45 to about 65 mS/cm, said developer also comprising at least 0.2 weight % of one or more water-soluble or water-dispersible polyhydroxy compounds as conductivity reducing agents, wherein said developer composition is regenerated by adding to it an alkali silicate-containing regenerator composition having a pH of at least 12 and a conductivity of from about 50 to about 70 mS/cm, provided that the conductivity of said regenerator composition is greater than the conductivity of said developer composition by at least 3 mS/cm, wherein both of said developer composition and regenerator compositions independently contain from about 0.2 to about 10 weight % of glycerin as a conductivity reducing agent, and both of said developer composition and said regenerator composition further comprise the same or different alkylaminopoly(ethyleneoxy)polypropoxypropanol, wherein the weight ratio of glycerin in said regenerator composition to that in said developer composition is less than 0.95:1.