The pure titanium of the color development which is difficult to cause discoloration in atmospheric environment

摘要

The present invention provides colored pure titanium or titanium alloy having low susceptibility to discoloration in an atmospheric environment exhibiting a superior resistance to discoloration even when the titanium is used in an environment of harsh acid rain such as a roof or wall material and free from deterioration of the aesthetic appearance over a long period of time, that is, colored pure titanium obtained by the anodic oxidation method, that is, colored pure titanium or titanium alloy having low susceptibility to discoloration in an atmospheric environment characterized by having an average phosphorus content in a range of 40 nm from a surface of a titanium oxide layer formed on the titanium surface of 5.5 atomic% or less and by having an average carbon concentration in a range of a depth of 100 nm from the titanium surface of 3 to 15 atomic%.