Oxyalkylated phosphorus acid esters as urethane fire-retardants

Claim 1

A POLYURETHANE FOAM FORMED BY REACTING A MIXTURE COMPRISING: (1) A POLYOL WHICH IS THE REACTION PRODUCT OF A POLYHYDROXY COMPOUND HAVING A HYDROXYL NUMBER BETWEEN ABOUT 150 AND ABOUT 400, CONTAINING ABOUT 3 TO ABOUT 8 HYDROYL GROUPS PER MOLEUCLE, AND AN ALKYLENE OXIDE CONTAINING FROM 2 TO 6 CARBON ATOMS PER MOLEUCLE, SAID POLYOL CONSISTING ESSENTIALLY OF ATOMS OF CARBON, HYDROGEN AND OXYGEN; (2) A PHOSPHORUS - CONTAINING, HYDROXYL - SUBSTITUTED COMPOUND RESULTING FROM REACTING AN ALKYLENE OXIDE CONTAINING 2 TO 6 CARBON ATOMS PER MOOLECULE WITH AN ALKYL ACID PHOSPHATE HAVING AN AVERAGE ACTIVE HYDROGEN FUNTIONALITY OF LESS THAN 2.0 AND GREATER THAN 1.0, SAID PHOSPHORUS CONTAINING VALUE OF BETWEEN ABOUT 150 AND ABOUT 400, SAID PHOSPHORUSCONTAINING POLYOL BEING SUBSTANTIALLY THE SOLE PHOSPHORUS-CONTAINING FIRE RETARDANT SOURCE IN SAID MIXTURE; (3) AN ORGANIC POLYISOCYANATE HAVING AN ISOCYANATO FUNCTIONALITY OF ABOUT 2.3 TO ABOUT 6 PER MOLEUCULE AND CONSISTING ESSENTIALLY OF HYDROCARBON GROUPS AND ISOCYANATO GROUPS; IN THE PRESENCE OF (4) A CATALYST OF URETHANE FORMATION FOR POLYOLS AND POLYISOCYANATES; (5) AN EMULSIFIER FOR THE MIXTURE; AND (6) A BLOWING AGENT.