申请人:Kuwano Hiroyuki
公开号:US20110168051A1
公开(公告)日:2011-07-14
The chromium (III) carbonate of the present invention exhibits a light blue color in a solid state. This chromium (III) carbonate has an L* value of 50 to 70, an a* value of −4 to −2, and a b* value of −10 to −7, which are represented by the L*a*b* color system (JIS Z8729). This chromium (III) carbonate is preferably completely dissolved within 30 minutes when the chromium (III) carbonate is added, in an amount corresponding to a Cr content of 1 g, to 1 liter of an aqueous solution of hydrochloric acid having a pH of 0.2 at a temperature of 25° C. This chromium (III) carbonate is preferably obtained by contacting an aqueous solution of carbonate and an aqueous solution containing trivalent chromium at a pH of 6 to 12 under the condition of a reaction liquid temperature of 0° C. or more and less than 50° C. Also, preferably, after production of the chromium (III) carbonate, filtration is performed, and the chromium (III) carbonate is washed with water until the conductivity of the filtrate is 5 mS/cm or less.
本发明的三价铬碳酸盐在固态下呈现淡蓝色。该三价铬碳酸盐的L*值为50到70,a*值为-4到-2,b*值为-10到-7,这些值由L*a*b*色彩系统(JIS Z8729)表示。当将相当于1克Cr含量的三价铬碳酸盐加入到1升pH为0.2的盐酸水溶液中,在25℃下,最好在30分钟内完全溶解。该三价铬碳酸盐最好是在碳酸盐水溶液和三价铬水溶液在pH为6到12的条件下接触,并在反应液温度为0℃以上但低于50℃的条件下进行制备。此外,最好在制备三价铬碳酸盐后进行过滤,并用水洗涤三价铬碳酸盐,直到过滤液的电导率小于5 mS/cm。