Preparation And Characterization Of Multi-Oxide Ceramic Pigment Nanometer Owder

In this study, precursors obtained by homogenous precipitation method. spinal-type black pigment precursor was homogenous precipitated from a mixed solution of nitrates using urea as precipitant, while tin spene-type pink pigment precursor was obtained using nitrate and chlorides as raw materials. Influence of two formulas CoxFe1-xCr2O4and CoFexCr2-xO4and their different metal iron ratio from black pigment precursor and tin chrome pink pigment different contents on coloration performance were firstly studied. Meanwhile,5wt%mineralization boric acid and holding time on cobalt black pigment have what impact on color rendering performance, which were also discussed. According to CIE L*a*b*testing results, the best formulation and ratio from black pigment and pink pigment are CoFexCr2-xO4(x=0.4) and Ca1.06SnSi1.21O5(Cr/Sn=0.025), respectively. Mineralization and too long holding time make blackness rise. Increasing the content of Cr3+ions from black pigment precursor, L value ranges from decline to increase, and a value and b value keep fluctuation very low, L、a、b values of the best color effect are18.45、1.23、-0.44. While Si/Sn ratio from pink pigment precursor were increased, L value hardly change, and a value and b value decrease. While increasing Ca/Sn ratio, Lvalue range from decline to stability, and a*value and b*value increase, L、a、b values of the best color effect are29.69,7.89、43.56.In order to solve agglomeration of ceramic pigment powder, precursors obtained by homogenous precipitation method were dried by supercritical CO2fluid drying technology to gain the well-dispersed, high actived powder, moreover improve the construction of product. The phase transformation, composition and micro-structural features of the products were by XRD, SEM, IR and CIE L*a*b*techniques. It was found that compared to the room temperature drying, precursor dried by supercritical CO2fluid technique not only well dispersed but also have good sinterability. Products calcinated at low temperature can generate pure spinel and pure tin sphene phase, respectively. Meanwhile, pigment powder in certain calcining temperature range can still keep good dispersion, and two kinds of pigment have more brightness. With sintering temperature increasing, powder particles gradually increase. XRD indicates that average grain size of precursor dried by supercritical CO2fluid drying technology calcined at low temperature is smaller than that of the conventional drying technology, but they are not that big of a difference when calcinated at high temperature.Reductive Sintering of pigments were also studied. The results show that black pigment can directly applied in sintering porcelain body surface, however, pink pigment cannot, glaze materials respectively mix with black and pink nano powder calcinated in air at900℃can perfect porcelains. Compared with industrial pigments, colour and lustre is more exquisite.