文件类型：PDF文档
文件大小：397K
Producing lanthanide phosphates comprises mixing a rare earth metal salt solution with a phosphate solution at a pH of 0-1 in a first precipitation step and then increasing the pH to more than 2 in a second precipitation step. - Independent claims are also included for : - (1) phosphate produced as above followed by washing, sieving, drying and calcining at 800-1000 deg. C; - (2) luminescent material produced from a phosphate as above by heating above 1000 deg. C, especially using an alkali metal or boron flux.