| abstract |
A 2,4,5-triphenylimidazole compound having the formula:n wherein each of R 1 to R 5 is a hydrogen atom, a Ci-C4 alkyl group, a Ci-C4 alkoxy group, a fluorine atom, a chlorine atom, a bromine atom, a trifluoromethyl group or a trichloromethyl group, and A is a hydrogen atom or a group having the formula:n wherein R 1 to R 5 are as defined above. |