Abstract: A composite metal hydroxide which is a solid solution of the formula (1),Mg.sub.1-x M.sup.2+.sub.x (OH).sub.2 (1)wherein M.sup.2+ is at least one divalent metal ion selected from the group consisting of Mn.sup.2+, Fe.sup.2+, Co.sup.2+, Ni.sup.2+, Cu.sup.2+ and Zn.sup.2+, and x is in the range of 0.001.ltoreq.x.ltoreq.0.9,a flame retardant containing the above composite metal hydroxide, and a flame-retardant resin and/or rubber composition containing the flame retardant.
Abstract: A composite metal hydroxide which is a solid solution of the formula (1),Mg.sub.1-x M.sup.2+.sub.x (OH).sub.2 ( 1)wherein M.sup.2+ is at least one divalent metal ion selected from the group consisting of Mn.sup.2+, Fe.sup.2+, Co.sup.2+, Ni.sup.2+, Cu.sup.2+ and Zn.sup.2+, and x is in the range of 0.001.ltoreq.x.ltoreq.0.9, a flame retardant containing the above composite metal hydroxide, and a flame-retardant resin and/or rubber composition containing the flame retardant.