SUBSTITUTED ε-IRON OXIDE MAGNETIC PARTICLE POWDER, PRODUCTION METHOD FOR SUBSTITUTED ε-IRON OXIDE MAGNETIC PARTICLE POWDER, GREEN COMPACT, PRODUCTION METHOD FOR GREEN COMPACT, AND ELECTROMAGNETIC WAVE ABSORBER

摘要

[Problem] To provide: a substituted ε-iron oxide magnetic particle powder that has another metal element substituted at a portion of the Fe sites of ε-Fe₂O₃ and contains a reduced amount of non-magnetic α-type iron oxide; and a production method for the substituted ε-iron oxide magnetic particle powder. [Solution] A substituted ε-iron oxide magnetic particle powder that contains a reduced amount of α-type iron oxide and is produced by neutralizing an acidic aqueous solution that includes trivalent iron ions and ions of a metal that is to substitute a portion of Fe sites to a pH of 2.0–7.0, adding a silicon compound that has a hydrolyzable group to a resultant dispersion that includes either iron oxyhydroxide that includes the substituent metal element or a mixture of iron oxyhydroxide and a hydroxide of the substituent metal element, neutralizing the dispersion to a pH of at least 8.0 before letting the dispersion age, and then coating the iron oxyhydroxide that includes the substituent metal element or the mixture of iron oxyhyrdoxide and a hydroxide of the substituent metal element with a chemical reaction product of the silicon compound and heating.