FOAMING POLYSTYRENE-BASED COLORING COMPOSITE RESIN PARTICLE, FOAM PARTICLE, FOAM MOLDING AND PRODUCTION METHODS FOR THE COLORED COMPOSITE RESIN PARTICLE, FOAM PARTICLE AND FOAM MOLDING

摘要

PROBLEM TO BE SOLVED: To provide a foaming polystyrene-based coloring composite resin particle giving a foam molding without uneven coloring, a foam particle, a foam molding and their production methods.SOLUTION: A method of producing a foaming polystyrene-based coloring composite resin particle includes a step of mixing a composite resin particle composed of a polyolefin-based resin and a polystyrene-based resin with a dye emulsion containing a dye and a cationic surfactant in a closed vessel and a step of pressure-injecting a foaming agent into the closed vessel to impregnate the composite resin particle with the foaming agent.