| 摘要 |
The invention relates to a process for the treatment of pigments based on rare-earth sesquisulphides, aimed more particularly at improving the colour of the latter, the said process being characterised in that it consists in subjecting the said pigments to a fluoridation treatment allowing fluorine atoms to be incorporated, preferably at the surface, within the said pigments. The invention also relates to new pigments based on rare-earth sesquisulphides with improved chromatic properties and characterised essentially in that they contain fluorine atoms, preferably at the surface. These fluoridised pigments may furthermore take an encapsulated form, preferably in silica. The invention finally relates to the use of the said pigments for colouring various materials, in particular plastics. |
