In titanium machining, the surface treatment of titanium dioxide is generally followed by inorganic surface treatment and then organic surface treatment. In the case of inorganic surface treatment coatings, the thickness of the film varies according to the application. Generally, when the main purpose is to improve the weather resistance, the thickness of the film is tightly skinned. Inhibit the photocatalysis of titanium dioxide. Although the weather resistance of rutile titanium dioxide is better than that of anatase titanium dioxide, the photochemical activity of rutile-type ferric titanium dioxide without surface treatment will still affect the life of the coating film, especially the newly developed acrylic and organic Silicone polyester and other resins, which can transmit ultraviolet light by themselves, are stable to light in the absence of titanium dioxide, so it is especially necessary to reduce the photochemical activity of titanium dioxide, while ordinary alkyd resins are exposed to sunlight Even if there is no photocatalysis of titanium dioxide, they will degrade. The thickness of this type of inorganic film is mainly adjusted by the thickness of SiO2. If you want to maximize the dry hiding power of titanium dioxide (such as titanium dioxide for flat latex paint), the film layer should be thick and spongy, which can effectively The distance between the pigment particles is increased to make the difference in the refractive index between the pigment and the air (2.76 ~ 1.06) larger than the difference between the refractive index of the pigment and the resin in the paint (2.76 ~ 1.50), thereby improving the light scattering ability and covering Strengthen.
Different surface treatment agents and treatment amounts, and even different treatment methods, will affect the properties of titanium dioxide (dispersibility, weather resistance, oil absorption, gloss, hiding power, surface area, isoelectric point, rheology, storage stability, etc.) Varying degrees of influence.
Surface Treatment Of Titanium Dioxide
