Composition for forming thermally-cured coating film and thermally-cured coating film
The composition is a composition for forming a thermally-cured coating film, and comprises polyurethane resin comprising at least one group selected from the group consisting of a methacryloyloxy group, an acryloyloxy group, a methacryloyl group, and an acryloyl group; polythiol; and solvent.
1. A composition, which is a composition for forming a thermally-cured coating film, and comprises polyurethane resin comprising at least one group selected from the group consisting of a methacryloyloxy group, an acryloyloxy group, a methacryloyl group, and an acryloyl group; polythiol; and solvent,
wherein the polyurethane resin is polyurethane resin which has been prepared through a urethane reaction employing as a starting material a diol comprising at least one group selected from the group consisting of a methacryloyloxy group, an acryloyloxy group, a methacryloyl group, and an acryloyl group.
2. The composition according to claim 1 , wherein a main chain of a connecting group which connects thiol groups in the polythiol consists of carbon atoms, or consists of a combination of at least one carbon atom and at least one oxygen atom.
3. The composition according to claim 1 , wherein the polythiol comprises a terminal group in the form of a thiol group.
4. The composition according to claim 2 , wherein the polythiol comprises a terminal group in the form of a thiol group.
5. The composition according to claim 1 , which further comprises a base.
6. The composition according to claim 5 , wherein the base is an organic base.
7. The composition according to claim 1 , wherein the polythiol comprises three or more thiol groups within a molecule.
8. The composition according to claim 1 , wherein the polythiol comprises at least one branched structure.
9. The composition according to claim 1 , wherein the polythiol comprises three or more thiol groups within a molecule as well as comprises at least one branched structure.
10. The composition according to claim 2 , wherein the polythiol comprises three or more thiol groups within a molecule.
11. The composition according to claim 2 , wherein the polythiol comprises at least one branched structure.
12. The composition according to claim 2 , wherein the polythiol comprises three or more thiol groups within a molecule as well as comprises at least one branched structure.
13. The composition according to claim 1 , wherein the polythiol comprises no hydroxyl group within a molecule.
14. The composition according to claim 1 , which comprises no polyisocyanate.
15. The composition according to claim 1 , wherein the polyurethane resin comprises at least one group selected from the group consisting of a sulfonic acid group and a sulfonate group.
16. The composition according to claim 1 , wherein the solvent comprises equal to or greater than 60 weight percent of ketone solvent.
17. A thermally-cured coating film, which has been prepared by subjecting the composition according to claim 1 to heat treatment.
18. The thermally-cured coating film according to claim 17 , which comprises polyurethane resin which has been prepared through Michael addition reaction with the polythiol and the polyurethane resin comprising at least one group selected from the group consisting of a methacryloyloxy group, an acryloyloxy group, a methacryloyl group, and an acryloyl group, and which is intramolecularly or intermolecularly crosslinked by a connecting group derived from the polythiol.