An antibacterial measure using titanium oxide includes mixing titanium oxide in a resin to form a coating resin, and then coating a key surface with the coating resin. This method requires formation of a coating layer on a resin molding and thus increases the number of the production steps and cost. Furthermore, in the method, a coating film containing an antibacterial agent is scraped off light by little at each time of keying, and thus the film is finally completely removed to lose its antibacterial function. A conceivable measure against this includes directly mixing a resin and an antibacterial agent. However, titanium oxide used as an antibacterial agent degrades a raw material resin. It has recently be thought that photocatalytic apatite as a substitute for titanium oxide also causes chalking, and an antibacterial coating layer has been formed on a surface of a resin molding. However, the inventor of the present invention found that photocatalytic apatite does not cause chalking, thereby achieving a resin containing the photocatalytic apatite.