Yuan Lei's Little Knowledge | Application of Talcum Powder in Coatings
The main component of talc is magnesium silicate containing water, which is white or white-like, fine, sand-free powder, and feels greasy by hand. It has excellent physical and chemical properties. Widely used in cosmetics, medicine and food, coatings, paper, plastics, rubber, cables, ceramics, etc. Let's take a look at the application of talcum powder in coatings.
Talc soft texture, low abrasiveness, and has high whiteness, good suspension and dispersion, can be used for white pigment and all kinds of water-based, oil-based, resin-based industrial coatings, primer, protective paint and so on.
Talc powder has good suspension and easy dispersion, and low corrosion, in the coating, talcum powder as a filler can play a skeleton role, reduce manufacturing costs and improve the film hardness of the coating. It also has the characteristics of improving the stability of product shape, increasing tensile strength, shear strength, pressure strength, reducing deformation, elongation, thermal expansion coefficient, high whiteness, uniform particle size and strong dispersion. The talcum powder with flake particle structure can make the coating film have high water resistance and impermeability of enamel. The talcum powder with fibrous particle structure can improve the rheological property and leveling property of the coating, and improve the weather resistance of the coating.
▼ From the paint type
Primer: Talcum powder can be used in a variety of industrial coatings, especially primers. The primer for steel structure can be used talc powder to improve the precipitation of the coating, the mechanical force of the coating film and the recoatability.
Water-based latex coatings: Talcum powder can give it good brushing, leveling, light retention, the resulting coating has good impact resistance and flexibility, but also high corrosion resistance and dry coating.
Solvent-based wood coatings: In solvent-based wood coatings, talcum powder is mainly used in PU transparent primer and PU solid color topcoat. Its low hardness helps to improve the polishing property of the paint film. On the other hand, the refractive index of talcum powder is similar to that of resin base material, so the transparency of the coating film is high, which can well reflect the natural texture effect of wood grain of the substrate.
Silicate coatings: adding ultra-fine talc powder to silicate coatings can improve the film-forming properties of coatings and improve the performance of coatings.
Silicone high temperature resistant coating: because the flake structure of talcum powder can improve the flexural rigidity of high temperature resistant coating at high temperature, so as to improve the adhesion of high temperature resistant coating at high temperature; on the other hand, the functional groups of talcum powder and silicone resin will react chemically under high temperature conditions to form a silicon oxygen bond with certain adhesive force and protective force. The structural stability of the coating is thereby maintained.
Other coatings: talcum powder is used for interior wall coatings, which can improve scrub resistance and workability; Used for anti-corrosion coatings, which can improve the protective effect due to the extension of the diffusion path of corrosive substances; Used for polyurethane waterproof coating filler, which can reduce the volume shrinkage of the coating during curing and improve the wear resistance and cohesiveness; It can also act as a separating agent for pigments to improve the coloring effect of pigments.
Talc, paint, improve, with, primer, structure, coating, for, good
The difference between barium sulfate（BaSO4） and barium sulfite（BaSO3）
Kaolin is a non-metallic mineral, which is a kind of clay and clay rock mainly composed of kaolinite clay minerals. Because it is white and delicate, also known as white earth. It is named after Gaoling Village, Jingdezhen, Jiangxi Province.