METHOD FOR PRODUCING POLYURETHANE FOAM WITH CLOSED CELL

摘要

PROBLEM TO BE SOLVED: To provide a method for producing a polyurethane foam with closed cells causing substantially no deterioration of its thermal conductivity with time. SOLUTION: This polyurethane foam with closed cells is obtained by molding a polyurethane foam with closed cells followed by aging treatment of the resultant foam in the presence of the vapor of a treatment agent consisting of a polar low-molecular weight compound having active hydrogen groups reactive with the isocyanate groups of the foam, wherein, the treatment agent is readily penetrated into the closed cell skeleton of the foam and reacts with the isocyanate groups left unreacted in the skeleton, therefore carbon dioxide to be generated by reaction between the residual isocyanate groups and water vapor can be suppressed efficiently, resulting in suppressing the increase of the carbon dioxide in the cells, thus providing the objective polyurethane foam causing substantially no deterioration of its thermal conductivity with time.