HEAT-INSULATING BOARD

摘要

PROBLEM TO BE SOLVED: To provide a heat-insulating board having lightweight, excellent strength and moisture permeability, and a small calorific value at the time of burning. SOLUTION: The insulating board is provided on one side or both sides of an inorganic board by laminating a polyurethane foam layer which is formed by polycondensing polyisocyanate with a polyol solution containing a lignin- based material soluble in the polyol in a dissolved state in the presence of water. The content of the lignin-based material is 2-40 wt.% of the whole polyurethane foam.