文件类型:PDF文档
文件大小:131K
PROBLEM TO BE SOLVED : To produce ferromagnetic metal powder for a coating type magnetic recording medium suitable for high density recording and to obtain a precursor thereof. SOLUTION : This precursor for producing magnetic powder is composed of acicular grains obtained by incorporating iron oxyhydroxide or iron oxide with Co, Al, Si and R (R denotes at least one kind among rare earth elements including Y), in which the surface layer part of grains in which the acicular grains contain Co by >0 to 50 at.% to Fe, and in which Al of 0.1 to 30 at.% to Fe is entered into solid solution is deposited with a layer containing Si and R (where the Si content in the grains is 0.1 to 10 at.% Fe, and the R content is 0.1 to 15 at.% to Fe).