A resin component (A1) and a compound (B0) represented by General Formula (b0) in which X.sup.0 represents a bromine atom or an iodine atom, R.sup.m represents a hydroxy group, nb1 represents an integer of 1 to 5, and nb2 represents an integer of 0 to 4, 1?nb1+nb2?5 is satisfied, Yb.sup.0 represents a divalent linking group or a single bond, Vb.sup.0 represents a single bond, an alkylene group, or a fluorinated alkylene group, R.sup.0 represents a hydrogen atom, a fluorinated alkyl group having 1 to 5 carbon atoms, or a fluorine atom, and Rb.sup.1 to Rb.sup.15 each independently represents a hydrogen atom or a substituent, and at least two of Rb.sup.1 to Rb.sup.5 represent a fluorine atom or at least one of Rb.sup.1 to Rb.sup.5 represents a perfluoroalkyl group

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Provided are, for example, (i) a drug that reacts with acrolein and (ii) a use thereof. A drug that reacts with acrolein in accordance with an embodiment of the present invention contains a compound having a chemical structure represented by Formula (1): ##STR00001##

Provided are, for example, (i) a drug that reacts with acrolein and (ii) a use thereof. A drug that reacts with acrolein in accordance with an embodiment of the present invention contains a compound having a chemical structure represented by Formula (1): ##STR00001##

Sulfonium and iodonium salts of a carboxylate having an aromatic ring to which a nitrogen-containing alkyl or cyclic structure is attached are novel. The onium salt functions as an acid diffusion controlling agent in a resist composition, enabling to form a pattern of good profile with high resolution, improved MEF, LWR and DOF.

Sulfonium and iodonium salts of a carboxylate having an aromatic ring to which a nitrogen-containing alkyl or cyclic structure is attached are novel. The onium salt functions as an acid diffusion controlling agent in a resist composition, enabling to form a pattern of good profile with high resolution, improved MEF, LWR and DOF.