| 摘要 |
<p>There are disclosed new greenish-yellow, yellow and orange-yellow pigments which consist substantially of bismuth vanadate of monoclinic structure, bismuth phosphate of monoclinic structure and aluminum phosphate of orthorhombic structure and which, in the case of the yellow and orange-yellow pigments, also comprise a compound based on Bi2O3 and V2O5 the X-rays diffraction pattern of which shows the following peaks: 1.87, 1.88, 2.41, 2.77, 2.80, 3.11, 3.82 and 7.6 A. The new pigments are characterized by a dominant wave length lambda D of from 573 to 586 m mu , and have a molar ratio of Bi3O3/P2O5 equal to 1, and a Bi2O3/V205 molar ratio of from 1.39 to 5.59, inclusive, while their molar ratio Al2O3/V2O5 lies within specified ranges of values. Also disclosed is a method for preparing the new pigments by calcining, in the presence of air, BiPO4, Al2O3 and V2O5 or compounds which generate Al2O3 and V2O5 during the calcination.</p> |
