Wet-chemical processing and angle-dependent optical properties characterization of mica/TiO2/Al2O3/M2O3 (M = Fe, Cr, Co) pigments

The four-layer structure angle-dependent pigments with compositions of Mica/TiO(2)/Al(2)O(3)/Fe(2)O(3), Mica/TiO(2)/Al(2)O(3)/Cr(2)O(3) and Mica/TiO(2)/Al(2)O(3)/Co(2)O(3) were firstly prepared by the wet-chemical coating method, respectively. The as-prepared pigments were performed by precipitating different metal ions, such as Cr(3+), Fe(3+), Co(2+) and Al(3+), on the pretreated substrates, mica titanium. The optical effects of four-layer structure pigments were investigated in detail by using the five angles' spectrophotometer. The angle-dependent spectral reflectance and color changes can be quantitatively measured, and the results show that the angle-dependent effects for the as-prepared pigment were improved by the increasing coated Al(2)O(3) layers.