Pigments anticorrosive function

Zinc chromate and zinc tetroxychromate have also been used successfully in anticorrosive paints. Both pigments function by releasing chromate ions which passivate the steel surface. In common with lead pigments, those... 

If the chemistry of the treated pigment surface is adapted to the functional groups of the binder, the pigment can be used in aqueous anticorrosive dispersions... 

Besides the metal effect pigments there are also metallic pigments and powders for functional coatings like anticorrosion, reflective, heat resistant and conductive coatings. These include zinc, stainless steel and silver pigments. 

Chem. Descrip. Polymethyl siloxane, methoxy-functional Uses Binder for highly pigmented paints, VOC-compliant coatings, heat-resist., anticorrosive paints containing aluminum powd. or zinc dust and heat-resist., pigmented matte finishes such as car exhaust paints food-contact coatings... 

Protecting metallic substrates against corrosion is one of the prime functions of most coatings. Corrosion resistant coatings are typically formulated using anticorrosive pigments and suitable binders with the optimum formulation parameters. In addition, organic compounds known as corrosion inhibitors are often added at low levels, and can effectively reduce the corrosion rate of a metal or slow down the individual corrosion reactions. 

Primers. The primer is a universal component of all anticorrosive coatings and is considered to be one of the most important element of a protective system. A good primer generally provides the ability to stifle or retard the spread of corrosion discontinuities such as pinholes, holidays, or breaks in the film. To perform satisfactorily they must themselves adhere well to the base metal or any surface conversion coating that might be present. They should also contain an adequate concentration of a leachable inhibitor, where this is considered an important feature of the protection system, and this is usually a chromate pigment. The primary functions of a primer are... 

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