Triarylsulfonium based photoinitiators for led cure of cationic, free radical and hybrid cationic/free radical formulations

A compound of formula (I):

• wherein:
• n is 1 or 2,
• Y is an anion, the valency of which is γ,
• when n is 2, X is chosen from a single bond, S and 0,
• when n is 1, X is R11,
• Ar is an optionally substituted aromatic cycle chosen from benzofuranyl, dibenzofuranyl, benzothiophenyl, dibenzothiophenyl and phenyl group,
• with the proviso that:
• when Ar is chosen from benzofuranyl, dibenzofuranyl, benzothiophenyl and dibenzothiophenyl, n is 1,
• when Ar is a phenyl group and n is 1, the —Ar—X group has formula:
• wherein:
• either R12 and R13 are linked with each other so that the —Ar—X group represents
• Wherein:
• R16, R17, R18 and R19 are independently chosen among H, a halogen, a (C1-C6) linear or branched alkyl group, a (C1-C6) linear or branched alkoxy group, a —O—(CH2)i—COOR28 or
• —(CH2)i—CH—(COOR28)2 group wherein i is 1 or 2 and R28 is H or a (C1-C4) linear or branched alkyl group, and
• R11, R14, R15 are independently H, a halogen, a (C1-C6) linear or branched alkyl group, a (C1-C6) linear or branched alkoxy group and —S-Ph-C(═O)-Ph,
• or R1 and RR are not linked with each other, and
• R, R1, R1, R14, and R15 are independently chosen from H, a halogen, a (C1-C6) linear or branched alkyl group, a (C1-C6) linear or branched alkoxy group, a pyrrolidin-1-yl, a -L-Ph1 group wherein L is a single bond, CH2 or O and Ph1 is a phenyl group optionally substituted by one or several substituents chosen from a halogen, a (C1-C6) linear or branched alkyl group and a (C1-C6) linear or branched alkoxy group,
• provided that at least one group among R11, R12 and R13 is chosen from a halogen, a (C1-C6) linear or branched alkoxy group, a pyrrolidin-1-yl, a -L-Ph1 group wherein L is a single bond, CH2 or O and Ph1 is a phenyl group optionally substituted by one or several substituents chosen from a halogen, a (C1-C6) linear or branched alkyl group and a (C1-C6) linear or branched alkoxy group,
• when Ar is a phenyl group and n is 2, the —Ar—X—Ar— group has formula:
• wherein R20, R21, R22, R23, R24, R25, R26 and R27 are independently chosen from H, a (C1-C6) linear or branched alkyl group, a (C1-C6) linear or branched alkoxy group and, a —O—(CH2)j—COOR29 or —(CH2)j—CH—(COOR29)2 group wherein j is 1 or 2 and R29 is H or a (C1-C4) linear or branched alkyl group,
• R1 and R6 are independently chosen from H, a halogen, a (C1-C6) linear or branched alkyl group, a (C1-C6) linear or branched alkoxy group and a —O—(CH2)k—COOR30 or
• —(CH2)k—CH—(COOR30)2 group wherein k is 1 or 2 and R30 is H or a (C1-C4) linear or branched alkyl group,
• Ph2 is a phenyl group optionally substituted by one or several substituents chosen from a halogen, a (C1-C6) linear or branched alkyl group and a (C1-C6) linear or branched alkoxy group,
• R2, R4, R5, R7, R8, R9 and R10 are independently chosen from H, a halogen, a (C1-C6) linear or branched alkyl group, a (C1-C6) linear or branched alkoxy group and a —O—(CH2)m—COOR32 or —(CH2)m—CH—(COOR32)2 group wherein m is 1 or 2 and R32 is H or a (C1-C4) linear or branched alkyl group.