A colored pearly luster pigment without any coloring materials was developed by electroless nickel plating onto titanium dioxide coated mica (TiO
2-mica) which showed interference color. Various appearance colors could be obtained by controlling the thickness of TiO
2-mica plate. Their appearance colors and blightness were almost equal to the interference color of TiO
2-mica of a raw material. SEM analysis showed that TiO
2-mica were coated with ultra fine nickel particles (particle size < 5nm). Furthermore, XPS analysis showed that the oxidation states of the nickel particle on the TiO
2-mica could be controlled with the drying temperature or through the calcinating process. Ni(OH)
2 and Ni were found in the sample treated at 25°C for 24 hr, and Ni
2O
2 and Ni at 150°C for 24hr. Nickel particle composed of Ni
2O
2 and Ni was stable at further calcination, because of the passive valence state Ni
2O
2.
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