Fireproof laminates

Claim 1

A fireproof laminate comprising a urethane modified polyisocyanurate foam as a core material and surface materials piled on both sides of the foam and having a fireproof property which passes Grade 2 incombustibility according to Japanese Industrial Standard A-1321 combustion test, which comprises: (a) a three-layer assembly composed of an asbestos paper as an upper layer, a matted or woven glass fiber as a middle layer and a metal foil having a thickness of less than 0.1 mm as a lower layer as a front surface material for said core material, said front surface material being united with said core material through said metal foil by self-adhesion of said foam; (b) an aluminum foil having a thickness of not more than 0.1 mm as a back surface material for said core material; (c) said core material being rigid and produced by reacting an organic polyisocyanate with a polyol having a hydroxyl equivalent of 30 to 2,000 in an amount of 0.05 to 0.5 equivalent per isocyanate group of said organic polyisocyanate in the presence of an isocyanate polymerization catalyst selected from the group consisting of (i) an alkali metal salt of a carboxylic acid having 2 to 12 carbon atoms and (ii) said alkali metal carboxylic acid salt and a combination of tertiary amino compound therewith, a blowing agent and if necessary, other additives, and having a density of 0.02-0.04 g/cm 3 and (d) said laminate having a total thickness of not more than 30 mm.