Reactive mixture for coating molded objects by means of reaction injection molding and coated molded object

摘要

A reactive mixture for coating moldings by reaction injection molding includes at least 40% by weight of (meth)acrylates having at least two double bonds. The reactive mixture also includes at least one photoinitiator and at least one thermal initiator. Furthermore, a coated molding includes a molding obtainable by injection molding processes. The molding includes polymethyl methacrylate, polymethylmethacrylimide, styrene-acrylonitrile copolymer, styrene-maleic acid copolymer, polymethyl methacrylate copolymer, or a combination thereof. A coating is obtainable by polymerization of (meth)acrylates having at least two double bonds, the coating having an adhesive strength rating of not more than 1 according to the cross hatch test and a decrease in gloss at 20° after a scratch resistance test according to ASTM 1044 (12/05) (applied weight 500 g, number of cycles=100) of not more than 10%.

主权项

1. A coated moulding comprising
a moulding which is obtained by an injection moulding process and comprises at least one polymer selected from the group consisting of polymethyl methacrylate, poly(meth)acrylimide, styrene-acrylonitrile copolymer, styrene-maleic acid copolymer and polymethyl methacrylate copolymers, and a coating which is obtained by polymerization of at least 90% by weight of a mixture of two or more (meth)acrylates having at least two double bonds, wherein at least one of the two or more (meth)acrylates has two or three double bonds, at least one photoinitiator, and at least one thermal initiator, wherein the mixture is first thermally cured and, after the thermal curing, cured by irradiation, and wherein the coating has an adhesive strength rating of not more than 1 according to the cross hatch test and a decrease in gloss at 20° after a scratch resistance test according to ASTM 1044 (12/05) (applied weight 500 g, number of cycles =100) of not more than 10%.