| 摘要 |
PURPOSE:To obtain the subject foamed material useful as a heat-insulation material, cushioning material, panel, board, etc., by impregnating a liquid mixture containing a mixed phenolic resin consisting of novolak and resol, a solvent, a foaming agent and a foam stabilizer into a nonwoven fiber sheet substrate, drying the liquid and foaming the composition. CONSTITUTION:A liquid mixture containing (A) a mixed phenolic resin consisting of novolak and resol, (B) a solvent of said resin (preferably a volatile polar organic solvent having a boiling point of <=120 deg.C, e.g. methanol or acetone), (C) a foaming agent (e.g. N,N'-dinitrosopentamethylenetetramine) and (D) a foam stabilizer (preferably silicone compound) is impregnated in a nonwoven fiber sheet substrate, dried and foamed to obtain the objective foamed product. The mixing ratio of novolak:resol is preferably 90:10 to 70:80 by weight. |
