METHOD FOR MANUFACTURING OPEN-CELL RIGID POLYURETHANE FOAM FOR VACUUM HEAT INSULATING PANEL-FILLER MATERIAL

摘要

PROBLEM TO BE SOLVED: To provide a method for manufacturing an open-cell rigid polyurethane foam molded body at a low material cost per unit volume of the molded body, permitting loading a large amount of a filler material and excellent in surface smoothness as well as excellent in loading properties, directional properties of expansion cells and uniformity in the foam density. ;SOLUTION: A mixture of expandable raw material components comprising a polyol component and an isocyanate component in an equivalent ratio of NCO/OH of about 0.55-0.95 and a blowing agent, preferably water, is cooled down to solidify before expansion and a curing reaction substantially proceed thereby to give a powder of the expandable raw material components, which, if necessary after addition of a filler material, is poured into a space to be molded, raised in its temperature and compressed to effect expansion molding thereby to give a compressed product, which is further subjected to compression molding to give the open cell rigid polyurethane foam molded body having an open cell content of at least 99% with its skin layer remained.;COPYRIGHT: (C)2001,JPO