endently an organic group having one or more carbon atoms, or they may be bonded with each other to form a ring. [0026] Preferable examples of the organic quaternary ammonium salt compound represented by the general formula (I) include a compound wherein at least one of R1, R2, R3 and R4 is a functional group having a partial structural unit (structures) shown below. [0027] In the units, AR1 repre