Paint coating system pigments

Chem. Descrip. Syn. hectorite CAS 12173-47-6 EINECS/ELINCS 235-340-0 Uses Thickenerforwaterborne paints/coatings, esp. pigmented systems Features For low to med. shear rheology allows for prod, of 20-25% pourable gels... 

Viscosity of Systems with Dispersed Phases. A large proportion of coatings are pigmented and, therefore, have dispersed phases. In latex paints, both the pigments and the principal polymer are in dispersed phases. The viscosity of a coating having dispersed phases is a function of the volume concentration of the dispersed phase and can be expressed mathematically by the Mooney equation (96), a convenient form of which is... 

These are the most important components of paint. Coatings can be either clear or opaque (containing pigments) and either solvent- or water-based. With solvent-based paints, after application, most of the solvent is lost through evaporation. These solvent-based coatings are mostly alkyds (name derived from alkyl/acid) or modified alkyd resins. Normally they contain 30% polymer solids higher solids content is limited by the increasing viscosity of the system. 

Bismuth vanadate pigments are used in the manufacture of lead-free, weather resistant, brilliant yellow colors for automobile finishes and industrial paints. They are suitable for the pigmentation of solvent-containing paints, water-based paints, powder coatings, and coil-coating systems. It can be mixed with other pigments... 

Since the 1970s a trend to use water-based coating systems and glues instead of solvent-based products has been apparent. Most water-based paints and lacquers use polyurethane or acrylate as binders. For technical reasons the systems still contain organic cosolvents as well as pigments, biocides and surfactants (Hansen et al., 1987). 

Organic coatings are used to block the penetration of carbon dioxide or chloride ions. They form a continuous polymeric film on the surface of the concrete, of a thickness ranging from 100 to 300 pm. The binder can already be present in the liquid paint as a polymer, or the polymer can be formed due to chemical reactions between monomeric components that are mixed just before application. Modem coating systems are usually built up of several layers applied consecutively. They are compatible with the alkalinity of the concrete and are based on various types of polymers (e. g. acrylate, polyurethane, epoxy), pigments and additives, and are made suitable for application by the addition of solvents or diluents. 

Although the term paint has been used for latex-based systems as well as many others, traditionally it refers to one of the oldest coating systems known—that of a pigment combined with a drying oil, usually a solvent. Drying oils (e.g., linseed, tung), by virtue of their multiple unsaturation, behave like polyfunctional monomers which can polymerize ( dry ) to produce film by a combination of oxidation and free-radical propagation. Oil-soluble metallic soaps are used to catalyze the oxidation process. 

Coatings for Sheet-Metal Cans and Containers. By far the most important area of use is the coating of sheet-metal containers and cans for the storage and preservation of food and other products. Thin sheets of galvanised steel (tin plate), nickel-plated steel (tin-free steel), or aluminum alloys are generally used as substrate. Untreated steel sheet may, however, also be used (e.g., to produce containers and drums for chemicals), and are usually coated with pigmented or nonpigmented paint systems (varnishes). 

Heavy-duty coating systems generally comprise two primer coats and two topcoats, modern system sometimes consist of one primer coat and two topcoats. The total dry film thickness (DFT) of such anticorrosive paint systems is 150 - 200 pm, each layer has a minimum DFT of 40-50 pm. Due to their excellent adhesion, the first and second primers prevent corrosion of the metal surface. The pigments and extenders allow the primers to react with ions (CD and SO4") that diffuse into the film from the atmosphere. The pigmented organic film also forms a barrier against humidity that may otherwise initiate a corrosive process. 

Uses Matting agent for paints/coatings, pigmented coatings, thin lacquer systems, water-based lacquers... 

Uses Dispersant for aq. systems, pigments, fillers, cosmetic base makeup, latex paints/coatings, trade sale enamels, polymerization, leather tanning, and water treatment crumb control agent in polybutadiene rubber mtg. 

Chem. Descrip. Ammonium polymelhacrylate sol n Uses Dispersant for pigments, fillers, ceramics, latex paints/coatings Properties Pale amber clear liq. very sol. in water systems dens. 9.1-9.4 ib/gai vise. 75 cps max. pH 8.0 25% total solids Daxad 34N10 [Hampshire]... 

Uses Wax that reduces settling of pigments and other additives and provides antiblocking and gloss control props, in low-vise, paints/coat-ings, esp. water-reducible systems... 

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