Method of manufacturing low density products of molded synthetic resin

Claim 1

A METHOD OF MANUFACTURING A MOLDED PRODUCT FROM BEADS OF SYNTHETIC RESIN IMPREGANATED WITH A BLOWING AGENT, WHICH METHOD COMPRISES THE STEPS OF: CONFINING THE BEADS IN A SPACE OF LIMITED VOLUMETRIC CAPACITY; HEATING THE BEADS TO EFFECT EXPANSION THEREOF TO FILL SUCH SPACE UNDER PRESSURE AND TO AGGLOMERATE AND FUSE THE BEADS TOGETHER; THEREAFTER INCREASING THE CAPACITY OF SUCH SPACE IN AN AMOUNT LESS THAN THE RESIDUAL CAPACITY OF THE BEADS TO EXPND, AND MAINTAINING THE BEADS CONFINED WHILE USING LATEN HEADT RETAINED IN THE BEADS FOR EFFECTNG CONTINUED EXPANSION WHILE THE BEADS RETAIN SUFFICIENT HEAT TO BRING ABOUT ADDITIONAL EXPANSION THEREOF TO FILL THE INCREASED SPACE, SUCH CONTINUED EXPANSION THEREOF TO FILL THEINCREASED LATENT HEAT RETAINED THEREIN FURTHER SERVING INHERENTLY TO REDUCE THE HEAT OF THE FUSED BEADS, AND REMOVING THE MOLDED PRODUCT FROM THE MOLD ONLY AFTER THE TEMPERATURE THEREOF HAS BEEN REDUCED AND THE CAPACITY FOR EXPANSION HAS BEEN TERMINATED AND THE FORM OF THE PRODUCT HAS BEEN DETERMINED.

Claim 2

A METHOD OF MANUFACTURING A MOLDED PRODUCT FROM BEADS OF SYNTHETIC RESIN IMPREGANATED WITH A BLOWING AGENT, WHICH METHOD COMPRISES THE STEPS OF: CONFINING THE BEADS IN A SPACE OF LIMITED VOLUMETRIC CAPACITY; HEATING THE BEADS TO EFFECT EXPANSION THEREOF TO FILL SUCH SPACE UNDER PRESSURE AND TO AGGLOMERATE AND FUSE THE BEADS TOGETHER; THEREAFTER INCREASING THE CAPACITY OF SUCH SPACE IN AN AMOUNT LESS THAN THE RESIDUAL CAPACITY OF THE BEADS TO EXPND, AND MAINTAINING THE BEADS CONFINED WHILE USING LATEN HEADT RETAINED IN THE BEADS FOR EFFECTNG CONTINUED EXPANSION WHILE THE BEADS RETAIN SUFFICIENT HEAT TO BRING ABOUT ADDITIONAL EXPANSION THEREOF TO FILL THE INCREASED SPACE, SUCH CONTINUED EXPANSION THEREOF TO FILL THEINCREASED LATENT HEAT RETAINED THEREIN FURTHER SERVING INHERENTLY TO REDUCE THE HEAT OF THE FUSED BEADS, AND REMOVING THE MOLDED PRODUCT FROM THE MOLD ONLY AFTER THE TEMPERATURE THEREOF HAS BEEN REDUCED AND THE CAPACITY FOR EXPANSION HAS BEEN TERMINATED AND THE FORM OF THE PRODUCT HAS BEEN DETERMINED.