What is the weatherability of iron oxide pigments?

Carbon + Iron Oxide is generally considered to be a multi-colored pigment that has many properties that are not found in other pigments, such as tinting strength, Boric Acid Flakes oil absorption, and the like. The weatherability of iron oxide pigments is described below.

The light fastness and weather resistance of Coating Of Iron Oxide Crossword Clue Iron Oxide Density are important indicators for measuring the application properties of pigments. Weatherability is a term used to describe various changes in the appearance and functional value of colored coatings. It covers a full range of external use capabilities such as color and gloss retention, chalking, adhesion and film integrity. Its initial impact is caused by exposure of organic binders to exposure to sunlight, Sodium Hexametaphosphate moisture, temperature changes and environmental pollution.

The pulverization is due to the increasing separation of the organic binder from the surface of the paint film, leaving the pigment exposed to the air and some extender particles, thus forming a powdery powdered appearance. This change will result in a change in color and a decrease in gloss.

Iron oxide has the function of shielding Titanium Dioxide ultraviolet radiation and can extend the application life of the coating.

To achieve excellent film weatherability, you must choose the right ingredients. According to different coating system environments, iron oxide pigments with different crystal forms and particle sizes can be selected to improve the weather resistance of the coating.

In general, inorganic pigments become darker and darker by the action of sunlight and the atmosphere, while organic pigments mostly fade. In general, the light resistance and weather resistance of inorganic pigments are much stronger than those of ordinary organic pigments. If the chemical stability of the pigment is poor, the chemical composition of the pigment will change due to the action of sunlight and the atmosphere. The color will also change due to the change of chemical composition. For example, the whitening of zinc bismuth in sunlight is due to the reduction of zinc sulfide to metal. Zinc. In addition to the chemical composition, the same pigment, if the crystal form or crystal lattice is different, will also have different light resistance and weather resistance. For example, the lead chrome yellow of monoclinic crystal is better than the lead chrome of orthorhombic crystal; the rutile titanium dioxide and the anatase titanium dioxide are both tetragonal, but the lattice is different, the former is stronger than the latter. Strong powdering ability.

In order to improve the light fastness and weather resistance of pigments, scientists and technicians at home and abroad have done a lot of work, for example, adding additives, coating the surface of pigment particles, and passivating the surface. Due to the different treatment methods, different grades of the same pigment are formed for selective use. Light resistance and weather resistance are usually measured by a rating method, that is, light resistance is preferably 8 in comparison with the standard.