| abstract |
COMPOUNDS OF THE FORMULA I@@(FORMULA 1)@@IN WHICH R1 IS, FOR EXAMPLE, C1-C20ALKYL OR PHENYL-C1-C6ALKYL WHICH RADICALS ARE UNSUBSTITUTED OR SUBSTITUTED; R2, R3 AND R4 INDEPENDENTLY OF ONE ANOTHER ARE PHENYL OR BIPHENYL, WHICH RADICALS ARE UNSUBSTITUTED OR SUBSTITUTED; WHEREIN THE SUM OF THE HAMMETT (SIGMA) CONSTANTS (ALGEBRAICSUM SIGMA) OF THE SUBSTITUENTS ON THE AROMATIC RADICALS R2, R3 AND R4 IS BETWEEN +0.36 AND +2.58; R8, R8, R14, 15 AND R16 ARE, FOR EXAMPLE, C1-C12ALKYL, PHENYL-C1-C6ALKYL OR PHENYL, AND G IS A RADICAL WHICH IS ABLE TO FORM POSITIVE IONS ARE SUITABLE AS PHOTOINITIATORS FPR PHOTOPOLYMERIZABLE COMPOSITIONS WHICH CONTAIN ACID GROUPS, IN THE PRESENCE OF A COINITIATOR OF DESIRED. |