FIELD: organic chemistry. SUBSTANCE: composition involves 100 mass p. at least one ethylene-unsaturated photopolymerizing compound and 0.2-0.5 mass p. photoinitiating agent of the formula (I) $$$ where: $$$ - $$$-alkyl or phenyl substituted with phenyl or $$$-alkoxy-group; $$$ - as indicated above group $$$ or residue $$$ or $$$; or $$$ and $$$ together with phosphorus atom form bicyclic ring with 4-8 carbon atoms; $$$ - free or halogen-substituted $$$-alkyl; free $$$-cycloalkyl or substituted with $$$-alkyl and/or $$$-alkoxycarbonyl; free trisubstituted phenyl or substituted with $$$-alkyl or $$$-alkoxy-group or mono- or multisubstituted phenyl substituted with halogen, and $$$ - $$$-alkyl under condition that at least one of residues $$$ and $$$ means the substituted alkyl residue and that $$$ and $$$ together with phosphorus atom form bicyclic ring, or that $$$ means the substituted cycloalkyl residue that can has alkyl residues as single substituents. Synthesized compounds were used in polygraphic industry. EFFECT: improved method of synthesis. 5 tbl
