Superfine talc is a water-containing magnesium silicate mineral. When it is used in coatings, it can impart excellent brushability, leveling, and gloss retention to coatings. It has high impact resistance and flexibility, and high hardness, and can effectively improve the corrosion resistance and dryness of the coating.
The amount of superfine talc added has an impact on the coating properties. When the added amount is large, the transmittance and adhesion of the coating decrease, and the flexibility and impact resistance of the coating hardly change. Due to the addition of ultra-fine talc, the solid content of the coating increases, and the surface drying ability and tackiness of the coating are improved. The Mohs hardness of talc is 1. The more talc added, the higher the hardness of the coating, and the characteristic structure of ultra-fine talc can effectively improve the leveling of the coating and reduce the defects of the coating. It can also effectively extend the diffusion path of the corrosive medium, thereby improving the corrosion resistance of the coating. However, adding too much superfine talc powder will increase the covering power of the coating and decrease the light transmittance. At the same time, the adhesion of the coating layer is decreased due to the weak bonding force between the talc powder layers and easy cracking. Because of its high aspect ratio, ultrafine talc can impart high impact resistance and fracture toughness to the coating, so the coating has stable flexibility and impact resistance.