Patent ID: 8039630

Claim:
A cationic compound denoted by the following general formula (I): wherein Ar 1 and Ar 2 each independently denotes an optionally substituted aryl group or aromatic heterocyclic group, L 1 denotes a single bond or a divalent linkage group, with at least one from among Ar 1 , Ar 2 and L 1 comprising one or more onium cations; R 3 and R 4 each independently denotes a substituent and may form a ring with a benzene ring substituted; m3 and m4 each independently denotes an integer ranging from 0 to 4, and plural R 3 s and R 4 s may be identical or different from each other when m3 and m4 are an integer ranging from 2 to 4; and further wherein, in said general formula (I), Ar 1 is denoted by: Ar 2 is denoted by: wherein R 1 and R 2 each independently denotes a substituent and may form a ring with a benzene ring substituted; one of m1 and m2 denotes an integer ranging from 0 to 5 and the other denotes an integer ranging from 1 to 5, and plural R 1 s and R 2 s may be identical or different from each other when m1 and m2 are an integer ranging from 2 to 5; at least one from among R 1 and R 2 denotes a substituent comprising a nitrogen cation; and said nitrogen cation is a tetra-substituted nitrogen atom cation or nitrogen atom-containing aromatic heterocyclic cation.