结晶分解法合成超细钴蓝颜料

Synthesis of Ultrafine Cobalt Blue Pigment Using Crystallization-Pyrolysis Process

研究了结晶分解法合成钴蓝颜料的工艺,采用铝和钴的硝酸盐或硫酸盐混合溶液为原料,蒸发结晶后获得硝酸盐或硫酸盐的混晶体。硝酸盐混晶体在1 000℃下煅烧2 h可获得尖晶石型产物,得到的粉体团聚严重;以硫酸盐为母盐则在1 200℃下煅烧2 h得到尖晶石型结构的产物,加入一定量助熔剂后合成温度下降约100℃,煅烧得到的产物团聚较少,形貌规则,粒度分布均匀;通过对颜料反射性能分析,探讨了母盐种类的选择对所得到产物的性能影响情况,硫酸盐结晶分解法可以获得具有优良反射性能的产物,适合作为彩色显象管中蓝色荧光粉的着色颜料。

Synthesis of uhrafine cobalt blue pigment using crystallization - pyrolysis process was investigated. With mixed solution of aluminum and cobalt sulfates or nitrates as pregnant material, the mixed crystal of sulfates or nitrates can be obtained after evaporation - crystallization. The cobalt blue powders with spinel structure can be formed by calcining mixed crystal of nitrates at 1 000 ℃ for 2 h, and the obtained powders were severely agglometated. While the spinel powders were formed by pyrolysis mixed crystal of sul- fates at 1200 ℃ for 2 h, and the forming temperature of spinel phase can be decreased by 100 ℃ due to incorporation of flux additives. Cobalt blue particles obtained by sulfates crystallization - pyrolysis process showed less agglomerates, with even size distribution and regular morphology. By analyzing the reflectivity spectra of blue pigment, the effect of varieties of pregnant salts on reflectivity were discussed, and it has shown that cobalt blue particles obtained by sulfates crystallization - pyrolysis process can be used as the contrast -enhancing luminescent pigment for color CRT tubes.