甘肃省黏土矿物应用研究重点实验室知识库

Bright blue CoAl₂O₄/halloysite hybrid pigments were prepared via combining chemical co-precipitation and calcination process. The obtained hybrid pigments were characterized by X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, high resolution transmission electron microscopy, and ultraviolet–visible spectroscopy. The introduction of halloysite not only decreased the calcining temperature for formation of spinel-type CoAl₂O₄, but also enhanced the color properties of CoAl₂O₄ pigments including hue, brightness and chroma. The hybrid pigments incoropated 60% halloysite presented excellent color properties (L^* = 54.6, a^* = −2.5, b^* = −50.4, h^* = 262.21, and C^* = 47.35) and excellent environmental resistance tolerance toward acid, alkali and ultraviolet light. In particular, the hybrid pigments could be well dispersed into water-based paint with good suspension stability. It indicated that the hybrid pigments could be served as a promising pigment with bright blue to be applied in various fields such as ceramics, water based paints, inks, etc.