Matting is to use a certain method to reduce the gloss of the coating film surface.
MattingPinkMatting principle:
Combined with the mechanism of surface gloss of coating film and the factors that affect gloss, People think that matting means using various means to destroy the smoothness of the coating film, increase the microscopic roughness of the surface of the coating film, and reduce the reflection of light on the surface of the coating film. It can be divided into two methods: physical extinction and chemical extinction.
The principle of physical extinction is:Add Matting powder makes the paint surface uneven during the film-forming process, increasing light scattering and reducing reflection. Chemical matting is achieved by introducing some light-absorbing structures or groups, such as polypropylene graft substances, into the paint to obtain low gloss.
With the improvement of people’s living standards With continuous improvement, people need coatings with different gloss. High-end matte paint attracts consumers with its naturalness, nobility and elegance. In addition, the surface of the matte coating can cover minor paint film defects and make the appearance uniform, which is welcomed by paint manufacturers. Therefore, how to select an appropriate matting agent according to the characteristics of the prepared coating to achieve the desired effect has become a major issue for coating formulators. Gloss control is an important component of a successful paint formulation.
Semi-gloss or matte powder coatings are sometimes required depending on the application. In order to reduce the gloss of the coating film, commonly used matting agents include ultrafine silica, talc, aluminum stearate, calcium stearate, low molecular thermoplastic resin, etc. To get a matting effect. You can use the following methods:
a. Use dry mixing method to mix powder coatings with different curing speeds When mixed, the gloss of the resulting coating film will be significantly reduced and it will have a matting effect. Since the highly reactive powder coating solidifies rapidly, the leveling and reaction of the slow-curing resin in the continuous phase is hindered, and the cured coating film eventually loses its luster. Although this method is effective, it increases manufacturing steps and costs.
b. Add thermoplastic resin. Adding cellulose acetate to epoxy powder coatings, and adding fine powdered low molecular weight polyethylene and polypropylene resin to polyester powder coatings can produce matt powder coatings. Coating film gloss is affected by manufacturing conditions. Because the addition of thermoplastic resin will affect the storage stability of the powder coating, the addition amount is limited to 2-3% of the resin amount.
c. Use a special curing agent with matting effect.
d. Add fillers with matting effects. Adding fillers such as ultrafine silica and talc significantly reduces the gloss. In particular, the particle size of the filler has a great influence on the gloss of the coating film. The larger the particle size, the lower the gloss. It should be noted that increasing the amount of filler will reduce the smoothness and mechanical strength of the coating film. In epoxy powder coatings, the effect of calcium carbonate particle size on the gloss of the coating film is shown in the table. Adding ultrafine silica and kaolin to acrylic and polyester powder coatings can produce matt coatings. In addition, matt coatings can also be obtained by adding waxes such as polyethylene paraffin and hydrogenated castor oil.
In recent years, my country’s paint industry has been in the ascendant, and the total paint output has also jumped to the forefront of the world. A related industrial group has been formed, actively promoting the technological revolution and development in the traditional painting field. During this period, high-gloss gloss paints were known for their bright and bright colors.�It is deeply loved by consumers and has dominated the paint market for a long time. However, with the continuous improvement of people’s living standards, on the one hand, consumers feel that high-gloss glossy paints are more reflective after being filmed, which is harmful to human eyes; on the other hand, consumers’ aesthetic concepts are increasingly leaning towards leisure, Stylish and personalized. Coupled with the booming demand of my country’s automobile and home appliance industries. These factors have led to a sharp increase in demand for low-gloss coatings with a soft appearance. At the same time, how to produce coatings with matting properties has become a problem that coating designers must consider.
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