| 摘要 |
PROBLEM TO BE SOLVED: To produce iron oxide particles which are well-balanced in coloring ability, hiding power, hue and kneadability with resin and excellent in heat resistance. SOLUTION: This iron oxide particles have a number average grain size of 0.1-1 μm, include at least one or more kinds of Zn, Si and Al at the inside and/or the surface of the particles which amount to 20 wt.% or more among the total particles and satisfy the following relations (1) and (2), wherein D50, D90 and D95 denote the grain sizes at which the cumulative numbers from the side of a small grain size of primary particles respectively amounts to 50%, 90% and 95% of total number of particles: 1.5D50<=D90...(1), 2.5D50<=D95...(2). |
