There are currently three kinds of synthetic resin paints with excellent performance—polyurethane varnish, polyester varnish and acrylic varnish. Polyurethane cleaning method is a new type of interior coating with superior performance. Due to the thick film and high solid content, the paint film dries like glass. Some people call it "glass paint" or "resin paint". Polyurethane varnishes are generally two-component, one component is a prepolymer made of isophenolic acid esters and polyols; the other component is a polymer compound containing a reductive group. It has less solvent content, thick and plump coating film, bright and smooth, good friction resistance, chemical resistance and heat resistance, so its performance is better than that of nitro paint, and it is easy to operate. There are currently commercially available polyurethane varnishes of various brands such as 685, 745, 7511, 7110 and S871.
Polyester varnish is formed by copolymerization of unsaturated polyester resin and styrene monomer in the presence of an initiator. Its coating film is thicker, plump in appearance, good in hardness, wear-resistant and chemical-resistant. At present, the polyester varnishes we often use generally have two types: wrong type and non-wax type. There is not much difference in its composition, only the way of oxygen barrier is different. The former uses paraffin wax in the paint to isolate oxygen, while the latter uses glass or polyester film to isolate oxygen during construction. Because the paint needs to be isolated from the air during construction, the construction procedures are relatively hemp, and it is only suitable for large-scale painting. For the convenience of construction, some manufacturers have produced three-component high-grade unsaturated polyester paints.
Acrylic varnish is a coating in which the copolymer resin of methacrylic acid ester and acrylic acid Sidang is the main film-forming substance. This kind of paint has better brightness and hardness, lighter color, good adhesion, strong wear resistance, strong chemical resistance, and extremely fast operation. Its disadvantages are high price, easy to become sticky when heated, high viscosity during operation, and easy to produce stringing or orangeness.
