Expandible polystyrene particles, their mixture , process for their preparation and shaped product prepared from them

摘要

Expandible polystyrene particles are provided with a marking formed by at least one brightening agent that absorbs UV rays. This brightening agent is incorporated in rod-shaped, extrusion-blown granulate particles with an essentially uniform grain size. A method for producing polystyrene particles of this type provides that polystyrene is extruded and granulated together with at least one expanding agent and at least one brightening agent.