Water-based coatings are composed of resins, pigments, fillers and additives. According to the application, water-based paints are further divided into: architectural paints, water-based industrial paints, water-based anti-rust paints, etc., but all kinds of paints are inseparable from the application of pigments, especially iron oxide pigments have become an indispensable variety of water-based paints. Iron oxide pigments are widely used in coatings, paints and inks because they are non-toxic, non-bleeding, low cost, and can form a variety of different tones.
Iron oxide pigments widely used in coatings include iron oxide red, iron oxide yellow, iron oxide black and other products.
Iron oxide red has good heat resistance, does not change color at 300°C, and its chemical structure is extremely stable. It can absorb the ultraviolet spectrum in sunlight, so it has a protective effect on the coating. Iron oxide red is resistant to dilute acid, alkali, water, solvents, and has good weather resistance. It is used in anti-rust coatings with a physical anti-rust function, which increases the compactness and mechanical strength of the coating, and prevents moisture in the atmosphere from penetrating into the metal layer.
Iron oxide yellow and iron oxide red have good light resistance, solvent resistance, alkali resistance, and dilute acid resistance. Its heat resistance is slightly worse. When heat treatment is carried out at 135℃/1h and 177℃/5min, it will gradually It loses crystal water and transforms to red phase, so it cannot be used in coatings with higher drying temperature.
Nowadays, synthetic iron oxide yellow is used in water-based coatings. The synthetic iron oxide yellow has high tinting power, brighter shade and good abrasiveness. It has the function of shielding ultraviolet radiation and can extend the application life of the coating.
Moreover, the synthesized iron oxide yellow can be combined with stable phthalocyanine blue, iron blue, etc. to form green, and iron red, iron black, etc., to form brown.
In the coloring of latex paint, a small amount of iron yellow color paste can be added to the titanium white paste to make it beige. The light resistance is better than that of monoazo organic yellow. It can also be mixed to obtain the bright color of the organic yellow. Degree and durability of iron yellow.
Iron oxide black can also be used to prepare primers. It is used as a primer for metal objects in vehicles and transportation equipment. It is easier to grind than carbon black.
