Isocyanate resin compositions and hot melt and pressure sensitive adhesives based thereon

A resin composition which comprises 50 to 90 parts by weight of at least one polymer selected from the group consisting of graft copolymer A.sub.2, graft copolymer A.sub.3, graft copolymer A.sub.4 and graft copolymer A.sub.5, shown below, having at least one isocyanate group and a number-average molecular weight of 10,000 to 200,000, and 50 to 10 parts by weight of a low-molecular-weight polymer (B), shown below, not having an isocyanate group and having a number-average molecular weight of 500 to 8,000:

• 1) graft copolymers A.sub.2 to A.sub.5 ;
• 1-1) graft copolymer A.sub.2 having at least one isocyanate group prepared by graft polymerizing a monomer (c) having a vinyl group and an isocyanate group in the molecule, a macromer (a) having a vinyl group at the end of the molecule, having a number-average molecular weight of more than 2,000 and a glass transition temperature above 20.degree. C., and an alkyl (meth)acrylate (b) having an alkyl group of 1 to 12 carbon atoms, and having a glass transition temperature of -75.degree. C. to -20.degree. C. for the alkyl (meth)acrylate portion;
• 1-3) graft copolymer A.sub.3 having at least one isocyanate group prepared by copolymerizing a monomer (h) having a vinyl group and an active hydrogen in the molecule, above described macromer (a) having a vinyl group at the end of the molecule, having a number-average molecular weight of more than 2,000, and a glass transition temperature above 20.degree. C., and alkyl (meth)acrylate (b) having an alkyl group of 1 to 12 carbon atoms, and further reacting with a polyisocyanate (d), and having a glass transition temperature of -75.degree. C. to -20.degree. C. for the alkyl (meth)acrylate portion;
• 1-4) graft copolymer A.sub.4 having at least one isocyanate group prepared by copolymerizing a monomer (c) having a vinyl group and an isocyanate group in the molecule and alkyl (meth)acrylate (b) having an alkyl group of 1 to 12 carbon atoms, in the presence of a thermoplastic resin (f), and having a glass transition temperature of -75.degree. C. to -20.degree. C. for the alkyl (meth)acrylate portion;
• 1-5) graft copolymer A.sub.5 having at least one isocyanate group prepared by copolymerizing a monomer (h) having a vinyl group and active hydrogen in the molecule and alkyl (meth)acrylate (b) having an alkyl group of 1 to 12 carbon atoms, in the presence of said thermoplastic resin (f), and further reacting with a polyisocyanate (d), and having a glass transition temperature of -75.degree. C. to -20.degree. C. for the alkyl (meth)acrylate portion;
• 2) low-molecular-weight polymer (B);
• low-molecular-weight polymer (B), not having an isocyanate group, prepared by polymerizing at least one monomer (g) selected from the group consisting of vinyl acetate and alkyl (meth)acrylate (b) having an alkyl group of 1 to 12 carbon atoms and having a glass transition temperature of -40.degree. C. to 80.degree. C.

A resin composition which comprises 40 to 90 parts by weight of at least one polymer selected from the group consisting of high-molecular-weight polymers D.sub.1 and D.sub.2, shown below, having at least one isocyanate group and a number-average molecular weight of 10,000 to 200,000, and 60 to 10 parts by weight of a low-molecular-weight polymer (E) or (B), shown below, not having an isocyanate group and having a number-average molecular weight of 500 to 8,000:

• 1) high-molecular-weight polymers (D);
• 1-1) high-molecular-weight polymer D.sub.1 having at least one isocyanate group prepared by copolymerizing a monomer (c) having a vinyl group and an isocyanate group in the molecule, and alkyl (meth)acrylate (b) having an alkyl group of 1 to 12 carbon atoms, and having a glass transition temperature of -75.degree. C. to -20.degree. C. for the alkyl (meth)acrylate portion;
• 1-2) high-molecular-weight polymer D.sub.2 having at least one isocyanate group prepared by copolymerizing a monomer (h) having a vinyl group and an active carbon in the molecule, and an alkyl (meth)acrylate (b) having an alkyl group of 1 to 12 carbon atoms, and further reacting with a polyisocyanate (d), and having a glass transition temperature of -75.degree. C. to -20.degree. C. for the alkyl (meth)acrylate portion;
• 2) low-molecular-weight polymer (E.sub.1) or (B);
• 2-1) low-molecular-weight polymer (E.sub.1), having at least one isocyanate group prepared by copolymerizing a monomer (c) having a vinyl group and an isocyanate group in the molecule and at least one monomer (g) selected from the group consisting of vinylacetate and alkyl (meth)acrylate (b) having an alkyl group of 1 to 12 carbon atoms, and having a glass transition temperature of -40.degree. C. to 100.degree. C.;
• 2-2) low-molecular-weight polymer (E.sub.3), having at least one isocyanate group prepared by copolymerizing a monomer (h) having a vinyl group and an active hydrogen in the molecule and at least one monomer (g) selected from the group consisting of vinylacetate and alkyl (meth)acrylate (b) having an alkyl group of 1 to 12 carbon atoms and then reacting this copolymer with polyisocyanate (d), and having a glass transition temperature of -40.degree. C. to 100.degree. C.;
• 2-3) low-molecular-weight polymer (B), not having an isocyanate group, prepared by polymerizing at least one monomer (g) selected from the group consisting of vinyl acetate and alkyl (meth)acrylate (b) having an alkyl group of 1 to 12 carbon atoms and having a glass transition temperature of -40.degree. C. to 80.degree. C.