Primers, general

I Adhesion to concrete primers generally are used under polyesters and urethanes to improve adhesion. 

Improve adhesion of dissimilar materials such as polymers to inorganic substrates. Also called primers. Primers generally contain a multifunctional chemically reactive species capable of acting as a chemical bridge. In theory, any polar functional group in a compound may contribute to improved bonding to mineral surfaces. However, only a few organofunc-tional silanes have the balance of characteristics required... 

Only when the mutation creates or abolishes a natural restriction site or one engineered by use of special PCR primers General method for point mutations... 

Chem. Descrip. Amorphous hydrated siiica CAS 7631-86-9 EINECS/ELINCS 231-545-4 Uses Matting agent in soivent- and water-borne architectural paints, board, coii and can coatings (< 0.75 mii), eiectrocoat primers, general industrial coatings, water-based coatings, printing inks, radiation-cured systems (< 0.75 mii), vinyi topcoats Features Med. porosity... 

Metal primers General purpose Electrodeposition Textile... 

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... 

Primer coatings are used to provide a functional boundary layer between the substrate and the topcoat Coating manufacturers design a variety of specialized primers to enhance total system performance for a variety of coating applications. Primers generally provide many or all of the following features ... 

Decorative and protective primers generally have demanding performance specifications, and are usually formulated at relatively low PVCs and high volume sohds. They usually are not designed to provide high hiding or intrinsic weathering resistance, since the topcoat can be independently optimized to provide these and other performance features. 

Primer vehicles based on emulsion polymer technology were introduced in the 1970s and have shown a steady increase in market share over the past 30 years. They are used in a variety of exterior and interior coating applications. Stain blocking primers are one of the most popular types, and are used to prevent discoloration of topcoats by a variety of materials, including tannin stains from wood, children s marker stains, water stains and nicotine stains. Water based primers generally block the transport of stains by two principle mechanisms ... 

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