Production of flexible cellular polyurethane material

Claim 1

THE PROCESS OF MANUFACTURING A FLEXIBLE CELLULAR STRUCTURE WHICH COMPRISES FORMING A MIXTURE OF WATER, AN ACTIVE-HYDROGEN-CONTAINING POLYMERIC MATERIAL HAVING AN AVERAGE MOLECULAR WEIGHT OF FROM 1000 TO 5000 AND AN AMOUNT OF ORGANIC POLYISOCYANATE PROVIDING FROM 2 TO 8 EQUIVALENTS OF ISOCYANATE PER MOL OF POLYMERIC MATERIAL AND PERMITTING SAID MIXTURE OT FOAM AND SET IN AN ATMOSPHERE CONTAINING AMMONIA FOR SUFFICIENT TIME AND AT SUCH CONCENTRATION OF AMMONIA AS TO MINIMIZE THE FORMATION OF NON-CELLULAR SKIN ON THE UPPER SURFACE OF THE FOAMED REACTION MIXTURE, THE FOAMILNG BEING ACCOMPLISHED BY THE GENERATION OF CARBON DIOXIDE IN SITU, SAID ACTIVE-HYDROGEN-CONTAINING POLYMERIC MATERIAL BEING SELECTED FROM THE GROUP CONSISTING OF POLYALKYLENE ETHER GLYCOLS, POLYESTERS PREPARED FROM THE CONDENSATION REACTION BETWEEN AT LEAST ONE DICARBOXYLIC ACID AND AT LEAST ONE GLYCOL AND POLYESTERAMIDES PREPARED FROM THE CONDENSATION REACTION BETWEEN AT LEAST ONE AMINO COMPOUND SEAT LEAST ONE GLYCOL AND AT LEAST ONE AMINO COMPOUND SELECTED FROM THE GROUP CONSISTING OF AMINO CARBOXYLIC ACIDS, AMINO ALCOHOLS AND DIAMINES, SAID POLYESTERS AND POLYESTERAMIDES HAVING AN ACID NUMBER NOT GREATER THAN 5.