Mixing, paint manufacturing

A combination of primary and auxiliary driers is often used to achieve optimum curing with the minimum drier dose. Some optimized combinations are sold as mixed driers. Most driers are added in the let-down stage of paint manufacturing, except for auxiliary driers such as zinc and calcium that are generally added to the mill base due to their effectiveness as wetting and dispersing agents. 

More stringent criteria of 99% or 99.9% mixing time are used in certain applications where a higher degree of uniformity is required (e.g., paint manufacture or pharmaceutical production). These values can also be obtained from the log variance graph. The linear response of log variance as a function of time is due to the exponential decay in concentration fluctuations. This relationship also allows one to calculate an arbitrary degree of uniformity from the 95% nfixing time ... 

Static mixers are used ia the chemical iadustries for plastics and synthetic fibers, eg, continuous polymeri2ation, homogeni2ation of melts, and blending of additives ia extmders food manufacture, eg, oils, juices, beverages, milk, sauces, emulsifications, and heat transfer cosmetics, eg, shampoos, hquid soaps, cleaning Hquids, and creams petrochemicals, eg, fuels and greases environmental control, eg, effluent aeration, flue gas/air mixing, and pH control and paints, etc. 

Barium carbonate also reacts with titania to form barium titanate [12047-27-7] BaTiO, a ferroelectric material with a very high dielectric constant (see Ferroelectrics). Barium titanate is best manufactured as a single-phase composition by a soHd-state sintering technique. The asymmetrical perovskite stmcture of the titanate develops a potential difference when compressed in specific crystallographic directions, and vice versa. This material is most widely used for its strong piezoelectric characteristics in transducers for ultrasonic technical appHcations such as the emulsification of Hquids, mixing of powders and paints, and homogenization of milk, or in sonar devices (see Piezoelectrics Ultrasonics). 

Automotive Refinish Paints. Paint for appHcation to automobiles after they have left the assembly plant is a significant market. Although some of this paint is used for fuU repainting, especiaHy of commercial tmcks, most is used for repairs after accidents, commonly just one door or part of a fender, and so forth. In order to be able to serve this market, it is necessary to supply paints that match the colors of aH cars and tmcks, both domestic and imported, that have been manufactured over the previous ten years or so. Repair paints for the larger volume car colors are manufactured and stocked, but for the smaller volume colors formulas are suppHed by the coatings manufacturer to the paint distributor that permit a reasonable color match for any car by mixing standard bases. 

Segregation is not only limited to the product but also to the containers and tools used with the product. Particles left in containers and on tools, no matter how small, can cause blemishes in paint and other finishes, as well as violate health and safety regulations. If these are such risks in your manufacturing process, procedures need to be put in place that will prevent product mixing. 

Ensure that all paints, particularly two-pack, are thoroughly mixed in accordance with the manufacturer s instructions. 

Cure systems, however, paint only part of the picmre with regard to the manufacture of mbber articles polymers and fillers are equally important in meeting performance requirements. In addition, compound mixing and processing play an important role in achieving final vulcanizate properties. 

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