Soft polyurethane foam from hydroxyl urethane prepolymer and polyester ether polyol

A heat-fusible soft polyurethane foam produced from a mixture of polyhydroxy compounds, a polyisocyanate, a catalyst, a foam stabilizer and a blowing agent, the improvement wherein the mixture of polyhydroxy compounds comprises

• a polyol containing a terminal hydroxyl group and an urethane bond obtained by the reaction of a polyol of component (A) and at least one polyol selected from the group consisting of components (B) to (H) with a polyisocyanate, wherein components (A) to (H) are defined as follows:
• (A) a low-molecular-weight polyhydroxy compound containing 2 to 4 functional groups and having a molecular weight of 60 to 200,
• (B) a non-aromatic polyoxyalkylene polyol having a molecular weight of 300 to 5,000 and obtained by adding an alkylene oxide to the low-molecular-weight polyhydroxy compound containing 2 to 4 functional groups and having a molecular weight of 60 to 300,
• (C) an aromatic ring-containing diol having a molecular weight of 230 to 5,000 and obtained by adding an alkylene oxide to an aromatic dihydroxy compound represented by the formula ##STR9## wherein R and R' each denote hydrogen or an alkyl group, or ##STR10## (D) a polyester ether polyol having a molecular weight of 500 to 6,000 and comprising a polyoxyalkylene glycol, said glycol having a molecular weight of 300 to 5,000 and obtained by adding an alkylene oxide other than ethylene oxide to a low-molecular-weight polyhydroxy compound containing 2 to 4 functional groups and having a molecular weight of 60 to 300, and optionally a low-molecular-weight polyhydroxy compound containing 2 to 4 functional groups and having a molecular weight of 60 to 300 as an alcohol component, and at least one compound selected from aliphatic dicarboxylic acids, aromatic dicarboxylic acids, and their anhydrides and derivatives as an acid component,
• (E) a polyester ether polyol having a molecular weight of 500 to 6,000 and comprising an aromatic ring-containing diol having a molecular weight of 230 to 5,000 and obtained by adding an alkylene oxide to an aromatic dihydroxy compound represented by the formula ##STR11## wherein R and R' each denote hydrogen or an alkyl group, or ##STR12## and optionally a low-molecular-weight polyhydroxy compound containing 2 to 4 functional groups and having a molecular weight of 60 to 300 as an alcohol component, and at least one compound selected from aliphatic dicarboxylic acids having 3 to 6 carbon atoms, aromatic dicarboxylic acids, and their anhydrides and derivatives as an acid component,
• (F) a polyester ether polyol having a molecular weight of 500 to 6,000 and comprising an aromatic ring-containing diol having a molecular weight of 230 to 5,000 and obtained by adding an alkylene oxide to an aromatic dihydroxy compound represented by the formula ##STR13## wherein R and R' each denote hydrogen or an alkyl group, or ##STR14## and optionally a low-molecular-weight polyhydroxy compound containing 2 to 4 functional groups and having a molecular weight of 60 to 300 as an alcohol component, and a mixture of aromatic dicarboxylic acids and long-chain aliphatic dicarboxylic acids having 7 to 14 carbon atoms, or their anhydrides or derivatives as an acid component,
• (G) polyoxytetramethylene glycol having a molecular weight of 500 to 5,000, and
• (H) (i) an acid-alcohol-condensation polyester polyol obtained from the low-molecular-weight polyhydroxy compound (A) containing 2 to 4 functional groups and having the molecular weight of 60 to 200 and at least one compound selected from the group consisting of aliphatic dicarboxylic acids, aromatic dicarboxylic acids and their anhydrides and derivatives or (ii) a polylactone polyester polyol formed by polymerizing .epsilon.-caprolactone, or a mixture of (i) and (ii).

A heat-fusible soft polyurethane foam produced from at least one polyhydroxy compound, a polyisocyanate, a catalyst, a foam stabilizer and a blowing agent, the improvement wherein the polyhydroxy compound is

• at least one polyol selected from the group consisting of components (D), (E) and (F) wherein components (D)-(F) are defined as follows:
• (D) a polyester ether polyol having a molecular weight of 500 to 6,000 and comprising a polyoxyalkylene glycol said glycol having a molecular weight of 300 to 5,000 and obtained by adding an alkylene oxide other than ethylene oxide to a low-molecular-weight polyhydroxy compound containing 2 to 4 functional groups and having a molecular weight of 60 to 300, and optionally a low-molecular-weight polyhydroxy compound containing 2 to 4 functional groups and having a molecular weight of 60 to 300 as an alcohol component, and at least one compound selected from aliphatic dicarboxylic acids, aromatic dicarboxylic acids, and their anhydrides and derivatives as an acid component,
• (E) a polyester ether polyol having a molecular weight of 500 to 6,000 and comprising an aromatic ring-containing diol having a molecular weight of 230 to 5,000 and obtained by adding an alkylene oxide to an aromatic dihydroxy compound represented by the formula ##STR15## wherein R and R' each denote hydrogen or an alkyl group, or ##STR16## and optionally a low-molecular-weight polyhydroxy compound containing 2 to 4 functional groups and having a molecular weight of 60 to 300 as an alcohol component, and at least one compound selected from aliphatic dicarboxylic acids having 3 to 6 carbon atoms, aromatic dicarboxylic acids, and their anhydrides and derivatives as an acid component,
• (F) a polyester ether polyol having a molecular weight of 500 to 6,000 and comprising an aromatic ring-containing diol having a molecular weight of 230 to 5,000 and obtained by adding an alkylene oxide to an aromatic dihydroxy compound represented by the formula ##STR17## wherein R and R' each denote hydrogen or an alkyl group, or ##STR18## and optionally a low-molecular-weight polyhydroxy compound containing 2 to 4 functional groups and having a molecular weight of 60 to 300 as an alcohol component, and a mixture of aromatic dicarboxylic acids and long-chain aliphatic dicarboxylic acids having 7 to 14 carbon atoms, or their anhydrides or derivatives as an acid component.