Photopolymerizable compositions with combined photoinitiators

Claim 1

A photopolymerizable composition having high sensitivity and providing a photohardenable layer having excellent layer strength comprising an addition polymerizable unsaturated compound containing at least two ethylenically unsaturated double bonds in the molecule thereof, a high molecular binder present in an amount of from 10 to 1,000 parts by weight based on 100 parts by weight of the polymerizable unsaturated compound, and photopolymerization initiators, wherein a 4,4-'bis(dialkylamino)-benzophenone represented by general formula I, a benzophenone derivative represented by general formula II and an organic compound selected from the group consisting of compounds represented by general formulae IIIa, IIIb, IIIc, IIId and IIIe are contained in said composition in combination as said photopolymerization initiators; ##STR11## wherein R represents an alkyl, cycloalkyl or hydroxyalkyl group having 1 to 6 carbon atoms or is combined with another R substituted on the same nitrogen atom to form tetramethylene, pentamthylene or oxybisethylene; ##STR12## wherein R 1 represents a hydrogen atom or ##STR13## X 1 and X 2 each represents an alkyl group, an alkoxy group, a carboxy group, an alkoxycarbonyl group, an aryloxycarbonyl group or a halogen atom; m and n each represents 0, 1 or 2 and when m and n each represents 2, X 1 and X 2 may be the same or different; ##STR14## Ar 1 : a substituted or unsubstituted phenyl or naphthyl group Z: a chlorine or bromine atom ##STR15## Ar 2 : a substituted or unsubstituted aryl group W: a hydrogen atom, an alkyl group or an aryl group Z: a chlorine or bromine atom Ar.sup.3 --SO.sub.2 CZ.sub.3 IIIc Ar 3 : a substituted or unsubstituted phenyl or naphthyl group Z: a chlorine or bromine atom ##STR16## Z: a chlorine or bromine atom ##STR17## R 2 : CZ 3 or a substituted or unsubstituted phenyl or naphthyl group R 3 : CZ 3 , NH 2 , NHR 4 , N(R 4 ) 2 , SR 4 , OR 4 , or R 4 R 4 : an alkyl, aryl or alkenyl group Z: a chlorine or bromine atom wherein each of said compounds of formulae I to II and compound having group III is contained in an amount of 0.1 to 50 parts by weight per 100 parts by weight of the polymerizable unsaturated compound, wherein the weight ratio of the compound represented by formula I to that of formula II is 1:20-10:1, wherein the weight ratio of the compound represented by formula I to that containing group of formula III is 1:20-10:1 and wherein the weight ratio of the compound represented by formula II to that containing group of formula III is 1:10-10:1.