Лако-красочные материалы — производство

This is an interesting class of pigments that are capable of producing special color or visual effects when used in coatings. Special effect pig­ments are of two types: pearl luster and interference pigments. They are based on natural or synthetic materials that exhibit outstanding qualities of luster, brilliance, and iridescent color effects. Interference and pearlescent […]

Kaolin or clay is a natural fine-grained, well-crystallized hydrous aluminum silicate mineral. Depending upon impurities, it is availa­ble in very white to grayish-white grades. The primary particles of clay are of lamellar shape, which contributes to good brushability and reinforcement of films. Due to its high oil absorption value and particle shape, it is also […]

Among the different chemical classes, this group of extenders has the most variety, with a wide range of properties and crystal forms. Following silicate extenders are important for the coating industry: Magnesium silicate (talc, asbestine, French chalk); (3MgO4SiO 2H2O) This category covers a number of minerals with varying chemical composition based on magnesia and silica. […]

Among the large group of sulfates, barium sulfate (BaSO4) is the predominant filler in coatings. Two types of barium sulfate are used in coatings: natural (barite) and synthetic (blanc fixe). Barite, a naturally occurring crystalline mineral, is the source for natural barium sulfate extender, which is often contaminated with color — producing impurities that are […]

Both natural and synthetic silica are used as extenders in the coa­ting industry. Naturally occurring silica exists as three types: • Crystalline silica (the mineral quartz) • Amorphous silica (cryptocrystalline; the mineral tripoli) • Diatomaceous silica, also known as diatomaceous earth (kieselgur) Most of the natural silica used in coating industry has a SiO2 con­tent […]

Calcium carbonate (CaCO) Calcium carbonate is one of the most widely used fillers in the coating industry. Natural calcium carbonate is obtained by grinding of chalk (whiting), limestone, calcite and marble. Except for chalk, the other forms are crystalline. Synthetic calcium carbonate, often referred as precipitated calcium carbonate, is often produced by passing car­bon dioxide […]

Extender pigments, also referred to as fillers, supplemental pig­ments or functional filler, are fine white powders of low refractive index (<1.7), which are substantially insoluble in the vehicle, reaso­nably chemically inert, and commonly but not always inexpensive. In addition to their traditional use for reducing cost (and thus why they are also called fillers, though […]

Molybdate-based pigments inhibit corrosion by passivating the ano­dic sites by formation of a protective layer on the substrate through molybdate ions. Pure molybdate-based pigments have limited com­mercial importance due to their high cost. Therefore, they are com­bined with phosphate pigments or are coated onto inorganic fillers like calcium carbonate and zinc oxide. Some important molybdate […]

Alkalinity of borates is one of the important attributes of their inhibitive properties. They may also form calcium or barium soaps, depending on the pigment, with acidic functional groups in the resin. Borates act as anodic passivators, forming a protective film on metallic substrates. Barium metaborate (Ba0B203H20) Barium metaborate is the most important borate pigment. […]

These pigments contribute anticorrosive properties through anodic passivation through phosphite ions. The most important phosphite pigment used in the coating industry is zinc hydroxyl phosphite, with the theoretical formula [2 Zn(OH)2-ZnHPO3]-xZnO, where x = 0 to 17.