Ultraviolet cured coating and application thereof

Abstract

The invention belongs to the technical field of coating compositions and solves the problems of decreased adhesion of the coating to the magnesium alloy surface and easy ageing and cracking of the coating in the prior art. An ultraviolet cured coating comprises the following components in percentage by weight: a hardened first coat comprising 6 to 18 percent of low-functionality monomer, 30 to 51 percent of low-functionality prepolymer, 5 to 8 percent of alumina powder; 0.5 to 1.5 percent of antioxidant, less than 3 percent of auxiliary agent, 1 to 3 percent of photoinitiator and 18 to 35 percent of mixed solvent, an intermediate coat comprising 3 to 15 percent of low-functionality monomer, 35 to 57 percent of low-functionality prepolymer, 0.5 to 6 percent of transparent pigment, 1 to 4 percent of auxiliary agent, 1 to 3 percent of photoinitiator and 23 to 45 percent of mixed solvent, and a high-gloss cover coat comprising 1 to 8 percent of low-functionality monomer, 8 to 15 percent of low-functionality prepolymer, 10 to 22 percent of high-functionality monomer, 36 to 45 percent of high-functionality prepolymer, 1 to 4 percent of auxiliary agent, 3 to 5 percent of photoinitiator and 20 to 40 percent of mixed solvent.

Description

technical field [0001] The invention belongs to the technical field of coating compositions. Background technique [0002] As we all know, magnesium alloy is one of the lightest engineering metal materials. It has many advantages such as high specific strength and specific stiffness. It is the metal material with the most development potential in this century. It is widely used in aerospace, automobile manufacturing, electronic communication and other fields. However, the loose, porous, and easily oxidized surface of magnesium alloy materials also greatly restricts the application of this type of alloy material. Therefore, people have worked hard and done a lot of research work. The protection method is reported, and the organic coating protection technology is an effective method. Chinese patent CN1486795 discloses a three-layer decorative and protective coating consisting of a powder coating, an acrylic resin coloring layer and a UV-curable topcoat. The process is relativ...

AI Technical Summary

Problems solved by technology

Chinese patent CN1486795 discloses a three-layer decorative and protective coating consisting of a powder coating, an acrylic resin coloring layer and a UV-curable topcoat. The process is relatively complicated and the processing cost is high; Layer UV curing protective coating and Chinese patent CN101376790 introduce a primer coating composed of hydroxyl-containing saturated polyester resin, amino resin and epoxy resin, all of which belong to a protective coating. The process is relatively simple and has no aesthetic effect. Its performance is also difficult to meet the standards of the mobile phone industry

There are two main reasons: one is that the thermal expansion and contraction properties of magnesium alloy materials and UV materials are too different, and the large temperature difference will easily cause the adhesion to drop; the second is that the multiple curing of UV coatings will easily lead to aging and cracking of the coating film.

Images