PLATE-SHAPED FOAMED BOARD FORMED OF POLYPROPYLENE RESIN

摘要

PROBLEM TO BE SOLVED: To provide a plate-shaped foamed board formed of a polypropylene resin provided with excellent heat insulating characteristics, by forming an extremely thin layer low in density and extremely useful as a structural material and a heat insulating material for walls or alcove partitions in a building. SOLUTION: An extruded plate-shaped foamed board with a thickness of 10 mm or more formed of a polypropylene resin has a film parallel to the surface of the board and formed by the adhesion of cell membranes, and/or a layer formed from fine cells flat in the thickness direction of the board and having a thickness of 20-400μm and a ratio of a cell size in the width wise direction of the fine cells to a cell size in the thickness direction thereof of 2 or more in the cross section in the thickness direction of the board. The thickness of the cell membranes forming the layer is 50μm or less and the layer is present on the whole surface of the foamed board.