| abstract |
A method of producing a phenolic resin foam is provided. The method includes foaming and curing, on a surface material, a foamable phenolic resin composition containing a phenolic resin, a surfactant, a curing catalyst, and at least one selected from the group consisting of a chlorinated hydrofluoroolefin, a non-chlorinated hydrofluoroolefin, and a halogenated hydrocarbon. The phenolic resin has a weight average molecular weight Mw of at least 400 and no greater than 3,000 as determined by gel permeation chromatography. The phenolic resin has a viscosity at 40° C. of at least 1,000 mPa·s and no greater than 100,000 mPa·s. The phenolic resin has a viscosity increase rate constant of at least 0.05 (1/min) and no greater than 0.5 (1/min). |