Leydig, Voit & Mayer
Process for producing acicular iron .alpha.-oxyhydroxide particle powder
 A process for producing acicular .alpha.-FeOOH particle powder having a narrow particle size distribution and a rectified shape and being highly dispersed is provided, which process comprises mixing with stirring an aqueous solution of a Fe(II) salt with an aqueous solution of an alkali in an equivalent ratio of alkali to Fe(II) salt of 1.5 or more, oxidizing the mixture with a O.sub.2 -containing gas, heat treating the resulting suspension of iron .alpha.-FeOOH particle powder to 60.degree. to 100.degree. C., further adding an aqueous solution of a FE(II) salt in a proportion of atom to molecule of Fe(II)/.alpha.-FeOOH of 0.5 to 10% and again oxidizing the mixture with a O.sub.2 -containing gas at 35.degree. to 55.degree. C. 
Chisso Corporation
C C C C G C C B
C01P C01P C01P C01P G11B C01G C01P B82Y
additional additional additional additional inventional inventional additional inventional
Masayoshi Jiro
Saito I