Patent ID: 7351513

Claim:
A planographic printing plate precursor comprising a substrate having disposed thereon a hydrophilic layer which includes hydrophilic graft chains and a crosslinked structure formed through hydrolytic polycondensation of an alkoxide of an element selected from Si, Ti, Zr and Al, wherein the hydrophilic layer includes a polymer compound represented by the following general formula (I): wherein each of R 1 , R 2 , R 3 and R 4 independently represents a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms; m is an integer of 0 to 2; n is an integer of 1 to 8; L represents a single bond or an organic linking group Y represents —NHCOR 5 , —CONH 2 , —CON(R 5 ) 2 , —COR 5 , —OH, —CO 2 M or —SO 3 M; R 5 represents an alkyl group having 1 to 8 carbon atoms; and M represents one of a hydrogen atom, an alkali metal, an alkaline earth metal and an onium, said planographic printing plate precursor further comprising an image forming layer on said hydrophilic layer.