CAS 7631-86-9 Silica For Industrial Paint

What is the role of silica matting powder in solvent coatings?

Mechanism of matting of silica matting powder: The varnish film without Matting Agent is in a mirror film flat state. When light

reaches the surface of the mirror film, part of the incident light is absorbed, part is reflected, and part of the reflection makes

the film shiny. The paint film containing Silica Matting Agent is evenly distributed in the paint film, producing a slightly rough surface.

It can be clearly seen from the scanning electron microscope photo of the coating cross section that the matting particles are

evenly distributed in the coating film. When the incident light reaches the uneven surface of the paint film, diffuse reflection will

occur, that is, scattering will produce low-gloss matte and matte appearance. High porosity. Good particle size distribution and

suitable silica matting agent surface treatment can obtain good matting effect.

Silica matting powder: The powder made by grinding natural SIO2 has a high impurity content. The main component is SIO2,

which cannot be called silica and has no matting properties. It can only be used as a filler in coatings and has no matting effect.

Silica matting agent as coating mainly generates SIO2, which is divided into Fumed Silica and Precipitated Silica. Its microstructure

is amorphous or glassy.

Silica system generated by precipitation method is mainly made of quartz sand, and is melted with sodium hydroxide or sodium

carbonate in a kiln at high temperature. Compared with natural silica, silica has high silica purity. It is highly inert. It is UV-resistant.

The refractive index of amorphous silica is 1.46, which is close to the refractive index of many epoxy resins in the coating industry.

Therefore, amorphous silica can be used as a matting agent for coatings with excellent optical properties.

Anticorrosion Pigments, Inkjet Receptive Coating, Matting Agent