| 摘要 |
<p>A phenolic foam comprising a phenolic resin base part and a cell part most of which is occupied by many fine cells and having a density of 10 to 100 kg/m3, wherein the fine cells contain a hydrocarbon and have an average cell diameter of 5 to 200 νm and the walls of at least most of the fine cells are constituted of a smooth surface of the phenolic resin base. Despite the use of the hydrocarbon as a foaming agent, the foam has a thermal conductivity comparable to that of foams made with a conventional fluorocarbon foaming agent, undergoes no change in thermal conductivity with time, is excellent in mechanical strengths including compressive strength, and has reduced brittleness.</p> |
