To understand why the white carbon black matting agent is added to the paint, I hope it will be helpful to you.


Pigment or filler is added into the coating to evenly distribute in the coating film and form a micro rough surface. The larger the surface particles and the greater the micro roughness, the lower the gloss. Sometimes, light calcium carbonate or talcum powder is used in the production of matt coatings. The amount of light calcium carbonate or talcum powder is large, which often exceeds the critical pigment volume concentration of the coating and makes the physical properties of the film worse, such as delamination and hard precipitation. The use of matting agents can avoid this phenomenon. The commonly used matting agents are divided into organic and inorganic types. The inorganic matting agent is mainly white carbon black matting agent, and its chemical composition is silicon dioxide, which is divided into two types: the surface is treated with organic substances and the surface is not treated. The application of white carbon black matting agent in coatings is discussed.


The white carbon black matting agent is made of quartz sand (powder) by grinding natural silicon dioxide. The content of impurities is high. The main component is silicon dioxide, which cannot be called white carbon black, and has no matting performance. It can only be used as a filler in the paint, and has no matting effect. The white carbon black matting agent used as the paint is mainly synthetic silicon dioxide, which is divided into two categories: gas phase white carbon black and precipitated white carbon black. Its microstructure is amorphous or glassy. Silica was synthesized by precipitation method with the quartz sand as main raw material, which was melted with the sodium hydroxide or sodium carbonate in a furnace at high temperature and then processed. Vapor phase white carbon black is prepared by hydrolysis of silicon tetrachloride vapor in hydrogen oxygen flame. Compared with natural silicon dioxide, white carbon black has high silicon dioxide purity, high inertia and UV resistance. The refractive index of amorphous silica is 1.46, which is close to that of many resins in the coating industry. Therefore, amorphous silica can be used as a matting agent in coatings, with good optical properties.