| 摘要 |
<p>PURPOSE:To obtain iron oxide pigment powder showing golden color by allowing both water-soluble salt and a compd. contg. Si to previously exist in alkali suspension incorporating ferric salt and subjecting the mixture to hydrothermal treatment. CONSTITUTION:Both 0.1-15.0mol. water-soluble salt for 1mol. Fe and a compd. incorporating 1.5-20.0mol.% of Si to 100% of Fe, expressed in terms of Si, are allowed to previously exist in alkali suspension incorporating ferric salt and having >=9pH. Then the aimed iron oxide pigment powder is obtained by subjecting this suspension to hydrothermal treatment. As the water-soluble salt, sulfate, nitrate, chloride and acetate, etc., of alkali metal are used. Furthermore, as the compd. incorporating Si, silicate of potassium and sodium and colloidal silica, etc., are used. As the reason of golden color shown by this iron oxide pigment, it is considered that both the particle form of iron oxide pigment and the surface state of the particle are concerned.</p> |
