as defined above, ##STR13## wherein R3 is as defined above; R is the same as R2, a methoxy group or an ethoxy group; and R5 is a methyl group or an ethyl group, ##STR14## wherein R5 is as defined above; R6 is an alkyl group having 7 to 20 carbon atoms; and R7 is the same as R5 and R6, and ##STR15## wherein R8 is an alkyl group having 4 to 20 carbon atoms and X is an anion. 5.