Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
155 words
-1-In a process for the production of a polyurea-polyurethane by the reaction of an organic polyisocyanate with a polyol and an aromatic diamine wherein at least one of the positions ortho to each of the amino groups is substituted by lower-alkyl, in the presence of a catalyst for the reaction between hydroxy groups and isocyanato groups, the improvement which comprises employing as the organic polyisocyanate an isocyanate-terminated prepolymer derived by reaction of 4,4'-methy- lenebis(phenyl isocyanate) with a polyol having a functionality from 2 to 3 selected from the class consisting of copolymers of ethylene oxide and propylene oxide having molecular weights from about 1000 to about 10,000, polytetramethylene glycols having molecular weights from about 600 to about 5,000 and polyester polyols having molecular weights from about 500 to 8,000, said polyol and said isocyanate being reacted in the proportion of about 0.01 equivalents to about 0.5 equivalents of said polyol per equivalent of said isocyanate.
Claim 2
Dependent Claim
40 words
-2-A process according to claim 1 wherein said organic polyisocyanate also comprises a minor amount of a liquefied form of 4,4'-methylenebis(phenyl isocyanate) obtained by heating the latter with a carbodiimide-forming catalyst to convert a portion of said isocyanate to carbodiimide.
Claim 3
Dependent Claim
48 words
-3-A process according to claim 1 wherein the organic polyisocyanate also comprises a minor amount of 4,4'-methylenebis(phenyl isocyanate) which has previously been reacted with from about 0.04 to about 0.2 equivalents, per equivalent of said isocyanate, of a diol selected from dipropylene glycol, tripropylene glycol and mixtures thereof.
Claim 4
Dependent Claim
37 words
-4-A process according to any of claims 1 to 3 wherein the polyol employed in the preparation of said prepolymer is a polyethyleneoxy-polypropyleneoxy diol having a molecular weight in the range of about 2000 to about 5000.
Claim 5
Dependent Claim
17 words
-5-A process according to claim 4 wherein said polyethyleneoxy-polypropyleneoxy diol has a molecular weight of about 3500.
Claim 6
Dependent Claim
20 words
-6-A process according to claim 1 wherein said prepolymer has an isocyanate content of about 9 to about 20 percent.
Claim 7
Dependent Claim
20 words
-7-A process according to claim 6 wherein said prepolymer has an isocyanate content of about 12 to about 16 percent.
Claim 8
Dependent Claim
26 words
-8-A process according to any of claims 1 to 7 wherein said aromatic diamine is selected from the class consisting of 1-methyl-3,5-diethyl-2,4-diaminobenzene, 1-methyl-3,5-diethyl-2,6-diaminobenzene and mixtures thereof.
Claim 9
Dependent Claim
16 words
-9-A process according to any of claims 1 to 7 wherein said aromatic diamine comprises 3,3',5,5'-tetraisopropyl-4,4'-diaminodiphenylmethane.
Claim 10
Dependent Claim
54 words
-10-A process according to any of claims 1 to 7 wherein said aromatic diamine is the product of the acid condensation of formaldehyde and a mixture of at least two different alkylated anilines of the formula wherein R 1 is selected from the class consisting of hydrogen and lower-alkyl and R 2 is lower-alkyl.
Claim 11
Dependent Claim
25 words
-11-A process according to any of claims 1 to 10 wherein the production of the polyurea-polyurethane is carried out using a reaction injection molding technique.