Additive composition for both rinse water recycling in water recycling systems and simultaneous surface treatment of lithographic printing plates

Abstract

Additive compositions suitable for rinse water used for processing lithographic printing plates, particularly to additive compositions for rinse water in water recycling systems, are disclosed. The additive compositions contain at least one water-soluble film-forming polymer; optionally, at least one pH regulating agent capable of maintaining the pH value of an aqueous solution at about 7 or below; and at least one compound selected from the group consisting of phosphonic acid derivatives of formula I. in which X is C2-C6 alkylene or in which: k is 0 or 1; m is 1, 2, or 3; p is 1, 2, or 3; r is an integer from 10 to 20; R1 and R3 are each independently H or C1-C4 alkyl; R2 and R4 are each independently H, OH or C1-C4 alkoxy; and Y is —R6N—(CH2)n—(NR5)q—, in which q is 0 or 1, n is an integer from 0 to 8, and R5 and R6 are each independently H, C1-C4 alkyl, or —CH2—P(O)(OH)2.

Dependencies are inferred from the claim text.