Patent · US Expired

Bismuth vanadate pigments and process for preparing same

US4251283A · kind A · utility

10Cited by
4References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 4, 1979
Grant dateFeb 17, 1981
Priority date
Expiry dateOct 4, 1999

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC01P2006/60
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

New greenish-yellow pigments based on BiVO.sub.4 are disclosed. The pigments consist of the product obtained by the calcination, in the presence of air, of a mixture of BiPO.sub.4, V.sub.2 O.sub.5 and an oxide MeO, in which Me is Ca, Ba, Mg or Zn, said calcining being conducted at a temperature of between 500.degree. and 800.degree. C. when Me is Ca, Ba or Mg; and between 500.degree. and 700.degree. C. when Me is Zn, the calcination being then followed by a slow cooling down and by wet grinding. These pigments show a molar ratio Bi.sub.2 O.sub.3 /P.sub.2 O.sub.5 equal to 1 while their molar ratios Bi.sub.2 O.sub.3 /V.sub.2 O.sub.5 are within given ranges, which depend on the nature of Me.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.