EXPANDABLE POLYSTYRENIC RESIN PARTICLE AND EXPANSION MOLDED ARTICLE OBTAINED USING THE SAME

摘要

PROBLEM TO BE SOLVED: To suppress permeation of contents contained in an expansion molded article, obtained by pre-expanding and molding an expandable polystyrenic resin particle, into the external wall of the molded article or the inside of the molded article. SOLUTION: An expandable polystyrenic resin particle containing 3.0-5.5 wt.% of an easily volatile blowing agent is employed, where isopentane accounts for 30-60 wt.% of the easily volatile blowing agent and the expandable polystyrenic resin article is covered with 0.2-0.5 pt.wt., based on 100 pts.wt. of the resin particle, of zinc stearate.