Being the compound material sheet which is superior in flexural rigidity and the compound material

摘要

As for this invention, the air gap quantity 5 volume % has with one or two outside layers A which consist of the glass fiber strengthening polypropylene which is under and the air gap quantity 20 or 80 volume % the core layer which consists of the glass fiber strengthening polypropylene which is, flexural, it regards the compound material seat to which rigidity is strengthened.