| abstract |
PROBLEM TO BE SOLVED: To provide a nonwoven fabric which satisfies heat-resistant morphology, strength, elongation, and water resistance, an aqueous resin composition for impregnating the nonwoven fabric, and an asphalt roofing sheet using the same. SOLUTION: (A) O-equivalent O having a number average molecular weight of 500 or more. A polyester diol having an H group, an organic diisocyanate compound having a b equivalent of an isocyanate group, and a chain extender having a molecular weight of less than 500 having a c equivalent of a functional group capable of reacting with the isocyanate group are added as necessary. 8 <b / (a + c) ≦ a polyurethane resin having a glass transition point of 0 ° C. or higher having hydrophilicity, which is reacted at a ratio of 1; (B) a water-soluble polymer having an OH group; and (C) a crosslinking agent that undergoes a crosslinking reaction with the OH group in the polyurethane resin and / or the water-soluble polymer, and (A), (B), (B) C) The weight ratio of (A) / (B) is 1 / 99-20 / 80 and the weight ratio of ((A) + (B)) / (C) is 99.9 / 0.1-70. Satisfies / 30. |