High resiliency polyurethane foams

Claim 1

Flexible polyurethane foams resulting from subjecting to foaming conditions a composition which comprises: (A) a polyol composition consisting essentially of (1) from about 50 to 100 percent by weight of a primary hydroxyl-containing polyether triol having an average hydroxyl equivalent weight of from about 900 to about 2500; (2) from 0 to about 50 percent by weight of a diol, a triol, or mixtures thereof wherein said polyols have an average hydroxyl equivalent weight of from about 900 to about 2500; (B) an organic polyisocyanate consisting of (1) from about 50 to about 100 percent by weight of 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, NCO-containing prepolymers thereof, or mixtures thereof, and (2) from 0 to about 50 percent by weight of an organic polyisocyanate having an average functionality of at least 2; (C) from about 0.1 to about 5.0 parts per 100 parts by weight of Component (A) of silica as an inorganic filler having a pH of from about 6.5 to about 8.5 and an average effective particle size of less than about 7 microns; (D) from about 1.0 to about 5 parts by weight of water per 100 parts by weight of Component (A); (E) from 0 to about 20 parts of a low boiling auxiliary blowing agent per 100 parts by weight of Component (A); (F) from about 0 to about 10 parts per 100 parts by weight of Component (A) of a crosslinker component; (G) from about 0.5 to about 4 parts by weight per 100 parts by weight of Component (A) of a catalyst or catalysts for urethane formation; (H) from about 0.005 to about 2.5 parts per 100 parts by weight of Component (A) of a silicone oil cell control agent; and wherein Components (A), (B), (D) and (F) are present in quantities so as to provide an NCO:active hydrogen equivalent ratio of from about 0.8:1.0 to about 1.3:1.0.