Urethane resin composition, fire resistance reinforcing method for building material, and fire resistance reinforcing structure of building material

摘要

To provide a fire proof reinforcement method of a housing material, and a fire proof reinforcement structure of a housing material capable of further sufficiently filling without protruding from the opening of the housing material.SOLUTION: A urethane resin composition 8 contains: polyisocyanate compound; polyol compound; catalyzer; a foaming agent; a foam control agent; and an additive agent. At least one of polyisocyanate compound and polyol compound contains aromatic ring; two or more methylene groups are linked; further, 0≤molecular weight of polyisocyanate compound)/(number of polymerizable functional groups in the polyisocyanate compound)≤1000; and/or 0≤(molecular weight of polyol compound)/(number of polymerizable functional groups in the polyol compound)≤1000; are satisfied. Also, the additive agent includes at least one selected from the group consisting of phosphoric esters, phosphate-containing flame retardants, halogen-containing flame retardants and metal hydroxide.SELECTED DRAWING: Figure 1