FIELD: chemistry.
SUBSTANCE: described is a polymerisable iodonium salt containing a positively charged iodine atom bonded with two aryl rings and a negatively charged counter-ion and at least one substitute containing a urethane and/or urea group, which is bonded with at least one of said aryl rings, wherein said substitute contains at least one functional group capable of cationic or radical polymerisation. Described also is a polyvinyl alcohol acetal copolymer containing at least one functional group, which is capable of cationic or radical polymerissation, preferably vinyl ether, alkoxy-methylacrylamide or alkoxy-methacrylamide. The invention also describes polymer binder for coating an offset printing plate from the polyvinyl alcohol acetal family, cellulose ether family and binder based on monomers, each containing at least one functional group capable of cationic or radical polymerisation. Described also is an offset printing plate coating solution containing said polymerisable iodonium salt, said polyvinyl alcohol acetal copolymer and said binder.
EFFECT: high quality of high-resolution image when the offset printing plate is used repeatedly.
17 cl, 25 dwg, 21 ex
