| abstract |
[Problem] The present invention addresses the problem of overcoming the weakness of acid resistance and the aggregation of primary particles that occur when the average width of primary particles of magnesium hydroxide is reduced. [Solution] The present invention provides a composite metal hydroxide represented by formula (1) that satisfies (A) and (B) below. (Mg) 1-X (M 2+ ) X (OH) 2 (1) (where, in the formula, M 2+ is at least one divalent metal selected from Cr, Mn, Fe, Co, Ni, Cu, and Zn, and the range of X is 0 < X < 0.5.) (A) The average width of the primary particles as measured by SEM is at least 10 nm and less than 200 nm; (B) the monodispersivity represented by the following formula is 50% or higher: monodispersivity (%) = (average width of primary particles as measured by SEM/average width of secondary particles as measured by dynamic light scattering) x 100. |