Patent ID: 6852363

Claim:
A method for the preparation of a lithographic printing plate, said method comprising dispensing information-wise by means of ink jet printing droplets of a fluid onto a surface of a lithographic receiver, said surface being a crosslinked hydrophilic layer on a flexible support, a metallic surface, an oxidized metallic surface or an anodized aluminum surface, wherein said fluid contains an oleophilizing compound in the form of a homogenous solution or a stable colloidal dispersion, said oleophilizing compound having in its chemical structure a single functional amidine group capable of reacting with said surface of said lithographic receiver wherein said oleophilizing compound is defined by the formula: wherein R1 to R3 are each independently selected from a group consisting of hydrogen, a substituted or unsubstituted, saturated or unsaturated aliphatic group, a substituted or unsubstituted aryl group, and a substituted or unsubstituted heteroaryl group; R4 is selected from a group consisting of hydrogen, a substituted or unsubstituted, saturated or unsaturated aliphatic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, NR6R7, OR8, and SR9, wherein R6 and R7 are each-independently selected from a group consisting of hydrogen, a substituted or unsubstituted, saturated or unsaturated aliphatic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, an acyl group, a carbamoyl group, a sulfonyl group, a phosphoryl group and an oxalyl group; wherein R8 and R9 are each independently selected from a group consisting of a substituted or unsubstituted, saturated or unsaturated aliphatic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, an acyl group, a carbamoyl group, a sulfonyl group, a phosphoryl group and an oxalyl group, with the proviso that at least one of R1 to R4 is different from hydrogen; each of R1 to R4 can combine together to form a ring wherein said fluid further contains a colorant.