Oxynitride composition based on an alkaline-earth metal and on tantalum or on an alkaline-earth metal and on niobium preparation processes and use thereof as a dye pigment

摘要

The invention concerns an oxinitrided composition based on an alkaline earth and at least one element selected between tantalum and niobium, characterised in that it has a global composition corresponding to formula (1): A1+yM1-yO(7-3y-6x)/2N2x in which A represents an alkaline earth, M represents tantalum or niobium or one of these two elements partially substituted by the other and y and x verify the following equations: 0.33/=y/=0.5 and 0x/=(7-3y)/6. The invention also concerns a composition based on strontium and tantalum and/or niobium characterised in that it has a global composition corresponding to formula (2): Sr1+yM1-yO(7-3y)/2 in which M is defined as above and 0.33y0.5. The oxinitrided composition can be used as dyeing pigment.