光触媒抗菌試験条件がチタン基板上の大腸菌生存率に与える影響 Effect of Testing Conditions for Photocatalytic Antibacterial Performance on <i>Escherichia Coli</i> Survival Rate of Ti Substrate

  To evaluate the antibacterial performance of photocatalytic coating, Japan Industrial Standard (JIS) committee has suggested the standard testing conditions for quantitative evaluation. However, these conditions had been constructed based on the experimental consideration from the coating formed on a glass substrate. In this study, to check the applicability of the JIS conditions to the coating on a titanium (Ti) substrate, the change of the survival rate of <i>Escherichia coli</i> (<i>E. coli</i>) on the Ti surface was evaluated. We confirmed that the decrease of microorganisms caused by dryness and UV-light were effectively suppressed by the use of these conditions. Furthermore, when testing the antibacterial performance of an anodic TiO₂ layer on a Ti substrate, its performance could be evaluated clearly. In conclusion, we confirmed that the survival rate of <i>E. coli</i> on the Ti substrate could be evaluated by using the experimental conditions described in the JIS.<br>