Soft polyurethane cold-foam prodn. from a polyol and an isocyanate - by metering the reactants, after pressurising, into a mixing chamber and discharging for foaming

摘要

Polyurethane cold-foam, esp. soft foam, is mfd. by metering a polyol and an isocyanate, under normal press., into a mixing chamber where the reactants are compounded by a rotary stirrer. The resulting mixt. is discharged from the mixing chamber for subsequent foaming. Specifically, the polyol component is mixed with a gas under super-pressure before the metering step and then metered, together with the gas, into the mixing chamber. Both reactants are mixed together at less than 2000 rpm. Frequent regular, cleaning of the equipment used, is unnecessary, without risk of impairment of the quality of the resulting foam.