Influences of electrolyzing voltage on chromatics of anodized titanium dentures

Abstract

The change of colors of anodized titanium and effects of applied electrolytic voltages on chromatics of anodized titanium were investigated. The titanium specimens were anodized in 0.5 mol/L sulfuric acid and 0.2 mol/L phosphate acid electrolyte by use of different voltages. The colors of anodized titanium were measured with a spectrophotometer, and then evaluated in the CIE1976Lab uniform color scale and Mussell notation. It is found that one given volt produces a specific color. The chromatic values expressed in L*a*b* fluctuate widely in different voltage conditions. The hues in Mussell's notations are distributed widely, which show as red, yellow, green and purple in its five basic colors and yellow-red, green-yellow, blue-green and purple-blue in its five in-between colors in the range of 5 to 80 V. Anodizing with 10 V and 45 V respectively, the titanium plates appear two brilliant goldish yellow colors, but the former color is on the reddish side slightly while the latter color shows greenish a little. The spectrums of the two colors are in the range of wavelengths of yellow to red. It can be concluded that the colors of the anodized titanium are dependent upon the applied voltages. The goldish yellow may be used to improve the esthetics of titanium dentures.