Glossy Paper Paint Chemical Material Silicon Dioxide

What are the matting principles of silica matting powder?

The principle of physical matting is: adding matting powder makes the surface of the coating uneven during the

film-forming process, increasing the scattering of light and reducing reflection. Chemical matting is to introduce

some into the coating, such as combining the mechanism of gloss generation on the surface of the coating and

the factors affecting the gloss. People believe that matting is to use various means to destroy the smoothness of

the coating, increase the surface micro-roughness of the coating, and reduce the reflection of light on the surface

of the coating. It can be divided into physical matting and chemical matting. Polypropylene grafted substances can

absorb light structures or groups to obtain low gloss.

With the continuous improvement of people's living standards, people need coatings with different glosses. High-end

matte coatings have attracted a large number of consumers with their natural, noble and elegant appearance. In addition,

the surface of matte coatings can cover minor paint film defects and make the appearance uniform and consistent, which is

welcomed by coating manufacturers. Therefore, how to select a suitable Matting Agent according to the characteristics of

the prepared coating to achieve the desired effect has become the main problem for coating formulators. Gloss control is an

important part of a successful coating formula.

Depending on the application, semi-gloss or matte powder coatings are sometimes required. In order to reduce the gloss of

the coating film, commonly used matting powders include silica, talcum powder, aluminum stearate, calcium stearate, low

molecular weight thermoplastic resins, etc. To obtain a matting effect. The following methods can be used:

a. Add thermoplastic resin. Adding cellulose acetate to epoxy powder coatings and adding fine powdered low molecular weight

polyethylene and polypropylene resins to polyester powder coatings can obtain matting powder coatings. The gloss of the

coating film is affected by the manufacturing conditions. Because the addition of thermoplastic resins will affect the storage

stability of powder coatings, the addition amount is limited to 2-3% of the resin amount.

b. Mix powder coatings with different curing speeds by dry mixing, then the gloss of the resulting coating film will be significantly

reduced, which will have a matting effect. Since the powder coating with high reaction activity cures quickly, the leveling and

reaction of the slower curing resin in the continuous phase are hindered, and the cured coating film eventually loses its gloss.

Although this method is effective, it increases the manufacturing process and cost.

c. Add fillers with matting effect. Adding fillers such as silica and talcum powder significantly reduces the gloss. In particular, the

particle size of the filler has a great influence on the gloss of the coating. The larger the particle size, the lower the gloss. It should be

noted that increasing the amount of filler will reduce the flatness and mechanical strength of the coating. In epoxy powder coatings,

the effect of calcium carbonate particle size on the gloss of the coating is shown in the table. Adding silica and kaolin to acrylic and

polyester powder coatings can produce matte coatings. In addition, adding waxy substances such as polyethylene paraffin and

hydrogenated castor oil can also produce matte coatings.

Anticorrosion Pigments, Inkjet Receptive Coating, Matting Agent