LIGHT RARE-EARTH RAW MATERIAL FOR PRODUCING CERIUM ABRADANT

摘要

PROBLEM TO BE SOLVED: To provide a light rare-earth material for producing a cerium abradant which comprises cerium as a major component and contains reduced amount of alkaline metals, alkaline earth metals and radioactive materials.;SOLUTION: The material contains light rare-earth elements in an amount of at least 35 wt.% in terms of oxides. Based on the total amount of rare-earth oxides, the amount of cerium is at least 50 wt.%, the amount of alkali metal oxides is at most 0.5 wt.%, the total amount of alkali metals and alkaline earth metal oxides is at most 1.5 wt.% and the total amount of thorium oxide and uranium oxide is at most 0.05 wt.%.;COPYRIGHT: (C)2004,JPO