| abstract |
A novel sulfonium salt having high sensitivity to an active energy ray, a photoacid generator comprising the sulfonium salt, and a photosensitive composition containing the photoacid generator. The sulfonium salt of the present invention is represented by the formula (a1). In the formula, R 1 and R 2 independently represent an alkyl group which may be substituted with a halogen atom or a group represented by the formula (a2), R 1 and R 2 may be mutually bonded to form a ring together with the sulfur atom in the formula, R 3 represents a group represented by formula (a3) or a group represented by formula (a4), A 1 represents S or the like, X - represents a monovalent anion, provided that R 1 and R 2 are simultaneously a halogen atom And is not an optionally substituted alkyl group. In the formulas (a2) to (a4), the ring Z 1 is an aromatic hydrocarbon ring, R 4 , R 6 , R 9 and R 10 are specific monovalent groups, R 5 , R 7 and R 8 are specific divalent A 2 and A 3 are S, etc., m 1 is an integer of 0 or more, and n 1 and n 2 are 0 or 1. |