In this study the applicability of the new flame retardant for the intumescent fire retardant coating (IFRC) daubed on the top of the plywood was investigated. The following are the three kinds of flame retardants used in this study: (I) the artificial mesophase graphite powder (MGP), (2) the sericite (Al-4(OH)(4)(KAl-Si3O10)(2)), and (3) the graphite/sericite mixture. The desirable sizes of MGP and sericite were obtained by sieving, and then the surfaces of MGP and sericite were modified using a mechanofusion system. The MGP and sericite were characterized using a scanning electron microscope (SEM). a particle size analyzer, and an energy dispersive spectrum (EDS). The IFRC, which consisted of 19.8% of the flame retardant, 15% of the dehydrate agent, 18% of the foaming agent, 7.2% of the resin binder, and 40% of the solvent, was prepared and daubed on the top of the plywood. The test of the fire protection of IFRC was conducted using a flammability 45 degrees tester. The IFRC with the flame retardant of the raw MGP (or sericite) was also prepared to study the effects of the size distribution and the configuration of the flame retardant on the capability of fire protection of IFRC. The mass ratio of MGP to sericite also substantially affects the capability of fire protection of IFRC. Most interestingly, the capability of the fire protection of IFRC with the flame retardant of the raw material is better than that of IFRC with the flame retardant of the sieved and surface-modified material. (C) 2009 Published by Elsevier B.V. on behalf of The Society of Powder Technology Japan.