Patent ID: 7718102

Claim:
A method of producing a stable resin froth used to produce a microcellural pad or belt comprising the steps of placing a thermosetable liquid polymer or prepolymer resin and nucleation surfactant in at least one tank, metering a frothing agent into said tank by way of at least one tube or sparge, drawing off said frothing agent via a pressure regulator from the headspace of said tank so as to reach a steady state of continuous flow of the frothing agent from said tube or sparge to said headspace of said tank, and agitating said thermosetable liquid polymer or prepolymer resin, nucleation surfactant and frothing agent through the use of an impeller at a controlled temperature and under a vacuum pressure sufficient to produce a froth having a specific gravity of from about 0.7 to 1.0 g/cc, said tube or sparge being located below the impeller.