Self-cleaning coating for metal substrate and preparation method and use method thereof

Abstract

The invention belongs to the technical field of coatings and particularly relates to a self-cleaning coating for a metal substrate and a preparation method and use method thereof. The self-cleaning coating for a metal substrate comprises an intermediate layer and a self-cleaning layer. The intermediate layer is sprayed on a metal substrate and the self-cleaning layer is sprayed on the intermediatelayer. The intermediate layer comprises polyurethane, nano-silica, butyl acetate and nano-talcum powder. The self-cleaning layer comprises nanometer titanium dioxide, ethanol, propanol and polyvinylalcohol. The self-cleaning coating for a metal substrate can utilize a photocatalytic reaction of titanium dioxide in the self-cleaning layer to realize a self-cleaning function. The polyurethane in the intermediate layer has corrosion resistance and prevents the self-cleaning layer from directly contacting with the metal substrate to inhibit metal substrate corrosion or decomposition.

Description

technical field [0001] The invention belongs to the technical field of coatings, and in particular relates to a self-cleaning coating for metal substrates, a preparation method and an application method thereof. Background technique [0002] Stain resistance has always been an important indicator for evaluating the quality of coatings. However, the current coatings generally have problems of poor stain resistance or unsustainable stain resistance. At the same time, there are also problems of paint corrosion or decomposition of base materials. This is both It affects the beauty of the coated object and increases the maintenance cost. Moreover, people pay more and more attention to environmental protection issues nowadays. Therefore, it is urgent to develop a coating that can be self-cleaning, environmentally friendly and does not damage its substrate. question. This is especially true for metal substrates. Nowadays, metal materials are widely used because of their excellent ...

AI Technical Summary

Problems solved by technology

Its self-cleaning layer can decompose organic pollutants adsorbed on the surface of titanium dioxide into CO by using the photocatalytic reaction of titanium dioxide. 2 and H 2 O, together with the remaining inorganic matter, it can be washed away by normal clean water or rainwater, so as to realize the self-cleaning function, and also decompose the organic matter emitted by the car to a certain extent. The polyvinyl alcohol contained in the self-cleaning layer is a kind of Excellent emulsifiers and adhesives can not only balance the material distribution of the self-cleaning coating, but also improve its tensile strength and wear resistance; the polyurethane contained in the middle layer has corrosion resistance and can prevent the self-cleaning coating It corrodes or decomposes the metal substrate by direct contact with the metal substrate. The nano-silica contained in the middle layer can improve the coating’s poor suspension stability, poor thixotropy, poor weather resistance, and poor scrub resistance, so that the combination of the coating film and the metal substrate The strength is greatly improved, the hardness of the coating film is increased, and the self-cleaning ability of the surface is also enhanced. In addition, the nano-talc powder included can improve the stability of the product shape, increase the tensile strength, shear strength, flexural strength, and pressure strength, reduce deformation, Elongation, thermal expansion coefficient, high whiteness, etc.

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