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US 4,483,894 AGranted
Process for applying polyurethane foams to substrates and product made thereby
AssigneeThe Dow Chemical Company
InventorsJames R. Porter, Randall C. Jenkines
Life of this patent
Estimating the term…
Abstract
Substrates having a backing of fine celled polyurethane foam are prepared by applying to the back of the substrate a frothed polyurethane forming composition containing small amounts of a silicone surfactant having an average molecular weight below about 30,000 which provides the resultant foam with a cell count value of greater than about 16 per 0.0025 square inches and wherein the unfilled, unfrothed liquid components of said polyurethane forming composition obtains a viscosity of greater than 10,000 centipoise in less than 40 minutes at 25.degree. C.
Claims24
A process for preparing substrates having a fine celled polyurethane foam backing containing an inorganic filler or mixture of such fillers, which process comprises applying to the back of said substrate and subsequently curing thereon a frothed polyurethane forming composition containing
- (A) a relatively high molecular weight polyether polyol having an average of from 2 to about 8, hydroxyl groups per molecule and an average hydroxyl equivalent weight of from about 100 to about 3000 or a mixture of such polyols;
- (B) a relatively low molecular weight polyol having an average of from about 2 to about 8 hydroxyl groups per molecule and an average equivalent weight of from about 31 to about 230 or a mixture of such polyols;
- (C) an organic polyisocyanate or polyisothiocyanate having an average of from about 2 to about 4 NCX (each X being independently O or S) groups per molecule or a mixture of such isocyanates or isothiocyanates;
- (D) at least one inorganic filler;
- (E) at least one catalyst for effecting the reaction between components (A), (B) and (C);
- and
- (F) at least one silicone surfactant which is a poly(dimethyl)siloxane polyoxyalkylene copolymer having an average molecular weight of less than about 30,000 and wherein at least about 60 percent by weight of the polyoxyalkylene groups are oxyethylene groups and the dimethylsiloxane content of the polymer is from about 15 percent to about 40 percent by weight and at least about 40 percent by weight of the polymer is derived from the oxyethylene groups;
- wherein:
- (1) components (A) and (B) are employed in a ratio which provides from about 50 to about 95 parts by weight of component (A) and from about 50 to about 5 parts by weight of component (B) based on 100 parts by weight for the total quantity of components (A) and (B) with the proviso
- (i) that the equivalent weight of (A) is at least 1.5 times greater than the equivalent weight of (B);
- (ii) that when component (A) has an average functionality of from 2 to about 8 and an OH equivalent weight of from about 1000 to about 3000 and either (a) an end cap of at least two moles of ethylene oxide per active hydrogen atom or (b) an internal block of at least three moles of ethylene oxide residues per active hydrogen atom, then component (B) need not be present;
- and
- (iii) that a mixture of components (A) and (B) or component (A) when employed alone has a Brookfield viscosity employing a No. 2 spindle at 12 rpm of at least about 100 centipoise at 25.degree. C.;
- (2) components (A), (B) and (C) are employed in quantities so as to provide an NCX:OH ratio of from about 0.85:1 to about 2:1,
- (3) component (E) is employed such that an unfrothed mixture of the unfilled urethane forming components (A), (B), (C), (E) and (F) obtains a viscosity of greater than about 10,000 centipoise at 25.degree. C..+-.0.5.degree. C. in less than about 40 minutes;
- and
- (4) component (F) is present in a quantity of from about 0.02 to about 0.5 parts per 100 parts by weight of the combined weight of components (A) and (B) and is of such composition and quantity so as to provide the foam with a cell count of greater than 16 per 0.0025 square inches (0.016 cm.sup.2) at a position approximately midway between the substrate-foam interface and the outer edge of the foam.
14 more elements
A process for preparing substrates having a fine celled polyurethane foam backing containing an inorganic filler or mixture of such fillers, which process comprises applying to the back of said substrate and subsequently curing thereon a frothed polyurethane forming composition containing
- (A) a relatively high molecular weight polyether polyol having an average of from 2 to about 8 hydroxyl groups per molecule and an average hydroxyl equivalent weight of from about 100 to about 3000 or a mixture of such polyols;
- (B) a relatively low molecular weight polyol having an average of from about 2 to about 8 hydroxyl groups per molecule and an average equivalent weight of from about 31 to about 230 or a mixture of such polyols;
- (C) an organic polyisocyanate or polyisothio cyanate having an average of from about 20 to about 4 NCX (each X being independently O or S) groups per molecule or a mixture of such isocyanates or isothiocyanates;
- (D) at least one inorganic filler;
- (E) at least one catalyst for effecting the reaction between components (A), (B) and (C);
- and
- (F) at least one silicone surfactant which is a branched organosilicon polyglycol block copolymer having an average molecular weight below about 30,000;
- wherein:
- (1) components (A) and (B) are employed in a ratio which provides from about 50 to about 95 parts by weight of component (A) and from about 50 to about 5 parts by weight of component (B) based on 100 parts by weight for the total quantity of components (A) and (B) with the proviso
- (i) that the equivalent weight of (A) is at least 1.5 times greater than the equivalent weight of (B);
- (ii) that when component (A) has an average functionality of from 2 to about 8 and an OH equivalent weight of from about 1000 to about 3000 and either (a) an end cap of at least two moles of ethylene oxide per active hydrogen atom or (b) an internal block of at least three moles of ethylene oxide residues per active hydrogen atom, then component (B) need not be present;
- and
- (iii) that a mixture of components (A) and (B) or component (A) when employed alone has a Brookfield viscosity employing a No. 2 spindle at 12 rpm of at least about 100 centipoise at 25.degree. C.;
- (2) components (A), (B) and (C) are employed in quantities so as to provide an NCX:OH ratio of from about 0.85:1 to about 2:1,
- (3) component (E) is employed such that an unfrothed mixture of the unfilled urethane forming components (A), (B), (C), (E) and (F) obtains a viscosity of greater than about 10,000 centipoise at 25.degree. C..+-.0.5.degree. C. in less than about 40 minutes;
- and
- (4) component (F) is present in a quantity of from about 0.02 to about 0.5 parts per 100 parts by weight of the combined weight of components (A) and (B) and is of such composition and quantity so as to provide the foam with a cell count of greater than 16 per 0.0025 square inches (0.016 cm.sup.2) at a position approximately midway between the substrate-foam interface and the outer edge of the foam.
14 more elements
Dependencies are inferred from the claim text.