Production of expansion-molded flame-retardant styrene resin article

PURPOSE:To provide a foamed styrene resin article having flame-retardancy and high dimensional stability and free from ignition danger even immediately after the expansion molding. CONSTITUTION:A flame-retardant is attached to the surface of styrene resin particles and an inorganic gas is pressed into the particles to obtain foamable particles. When the foamable particle contains more than specific amount of the inorganic gas, the particle is heated to a specific temperature by contacting with steam, the expanded particles are put into a mold and steam is blown into the mold to heat the particles at a specific temperature and obtain an expansion molded article.