| abstract |
A 4-aminopyridinium compound is represented by the formula (I) or (II). n n nin which each of L 1 and L 3 is —O—CO—, —CO—O—, —C≡C—, —CH═CH—, —CH═N—, —N═CH— or —N═N—; L 2 is a single bond, —O—CO—, —CO—O—, —C≡C—, —CH═CH—, —CH═N—, —N═CH— or —N═N—; m is 0 or 1; each of p and q is 1 to 10; each of R 1 and R 2 is an alkyl group or R 1 and R 2 are combined to form a ring; Z is cyano, an alkyl group, an alkoxy group, an acylalkyl group, an acylalkoxy group, an acyloxyalkyl group or an acyloxyalkoxy group; each of R 3 , R 4 and R 5 is a halogen atom; each of n1, n2 and n3 is 0 or 1; and X is an anion. |