Process for producing a rigid polyether-polyurethane foam

Claim 1

A PROCESS FOR PRODUCING POLYURETHANE FOAM WHICH COMPRISES CONJOINTLY REACTIN IN THE PRESENCE OF A BLOWING AGENT, A POLYETHER POLYOL WITH A COMPOSITION COMPRISING A TOLYLENE DIISOCYANATE SOLUTION OF CONGENERIC NON-VOLATILE POLYISOCYANATE SOLUTES, SAID SOLUTION BEING CHARACTERIZED BY THE FOLLOWING COMBINATION OF PARAMETERS: (1) A WEIGHT CONCENTRATION OF HEXANE INSOLUBLE CONGENERIC SOLUTE BETWEEN 20 AND 55%; (2) AN INFRARED ABSORPTION SPECTRUM INCLUDING ABSORBANCE MAXIMA IN THE REGIONS 4.3 TO 4.5 MICRONS, 5.8 TO 5.9 MICRONS, AND 5.95 TO 6.05 MICRONS, WHICH DEFINE AN ABSORBANCE PATTERN CHARACTERISTIC OF SAID SOL .E; (3) A MOLAR CONCENTRATION OF CONGENERIC SOLUTE SUFFICIENT TO IMPART TO SAID SPECTRUM, AT THE ABSORBANCE MAXIMUM BETWEEN 5.8 AND 5.9 MICRONS, AN ABSORBANCE BETWEEN 0.2 AND 0.5; (4) AN AMINE EQUIVALENT BETWEEN 98 AND 120; (5) A RECOVERABLE TOLYLENE DIISOCYANATE CONTENT, AS MEASURED IN A GAS CHROMATOGRAPH, BETWEEN ABOUT 55 AND 85 WEIGHT PERCENT; (6) A VISCOSITY BETWEEN 20 AND 10,000 CPSS. AT 25*C.; (7) A DENSITY BETWEEN 1.23 AND 1.29 AT 25*C.