TITANIUM-BASED MATERIAL RESPONSIVE TO VISIBLE LIGHT AND HAVING EXCELLENT PHOTOCATALYTIC ACTIVITY, AND PROCESS FOR PRODUCING SAME

摘要

Provided are beautiful chromatic titanium in which adhesion to the base constituted of pure titanium and a titanium alloy is satisfactory and which has excellent photocatalytic activity and a highly attractive appearance and a process for producing same using an anodizing process with excellent productivity. The chromatic titanium is a titanium-based material which is responsive to visible light and has excellent photocatalytic activity, and which comprises a base, the base being constituted of pure titanium and a titanium alloy, and a titanium oxide layer present on the surface of the base, the titanium oxide layer having a thickness in the range of 0.1-5.0 µm, comprising anatase titanium dioxide and hydroxy-bonded titanium, and containing nitrogen and carbon in an amount of 0.5-30 mass% each. The process for producing the titanium-based material comprises anodizing in an aqueous alkali solution containing nitrate ions in a concentration of from 0.01 M to saturation.