The casing 6, the front panel 1, the cross flow fan 9, the fan casing 10, and the louver 4 are molded a synthetic resin such as ABS resin, PP resin, PS resin or AS resin, to which 0.6-2.0 wt% of the antimicrobial agents of 2,4,4'-trichloro-2'-hydroxydiphenylether and N-(fluorodichloromethylthio)-phthalimide are added.