Water repellent coating

Resins, usually in a partially condensed form, are used to provide a water-repellent treatment for brickwork and masonry. Methyl-phenylsilicone resins are used as coatings for eletrical equipment and in the impregnation of class H electrical equipment. Dimethylsilicone fluids are also used as water-repellent coatings for class A or class B insulation. 

Water-repellent coatings for the protection of glass, plastic or metal surfaces can be obtained on the basis of a stannosiloxane chelate (reaction product from tributylchlorostannane and methyl octadecylchlorosilane)68). 

The halogenated hydrocarbons known as chlorofluorocarbons are a second class of materials that comprise water-repellent coatings. In particular, the substance known as l,l,2-trichloro-l,2,2-trifluoroethane or CFC-113 (Fig. 7.5.2) is... 

All dermatologic agents having a lipophilic base adhere to the skin as a water-repellent coating. They do not wash off and they also prevent (occlude) outward passage of water from the skia The skin is protected from drying, and its hydration and elasticity increase. 

Exemplary water-repellent treatments for masonry surfaces include metal stearates, oils, waxes, acrylates (both polymers and monomers), silicones (solvent-based and emulsion), siliconates, silanes and, fluorochemicals. In contrast, to waterproofing coatings, water-repellent coatings, because they are permeable to water vapor, do not trap moisture and, therefore they can reduce spalling. In addition most water-repellent coatings do not alter the appearance of a porous masonry. 

Promoters or collectors give the mineral the water-repellent coating that will adhere to an air bubble. Frothers enhance the formation and stability of the air bubbles. Other additives are used to control the pFI, to prevent unwanted substances from floating, or to control formation of slimes that may interfere with selectivity. 

Fire-retardant-treated wood is durable and stable under normal exposure conditions. Treatments using inorganic water-soluble salts, however, are not recommended for exterior exposures to rain and weathering unless the treatment can be adequately protected by water-repellent coating. Exterior-type treatments in which the chemicals are "fixed" in the wood in some manner are leach resistant and nonhygroscopic. 

USE In water-repellent coatings, candles, shoepolish, carbon paper, ointments and cosmetics for impregnating paper, wood, cloth for electrical condenser impregnation as solid lubricant as a pressure mold release agent in the manuf of formed plastics and rnbber goods. 

Chem. Descrip. Water-based silicone elastomeric emulsion Uses Water repellent, gloss aid, mar resist, aid for water-based inks and product finishes protective water repellent coating for woven and non-woven textiles and fabrics Features Imparts water and weather resist. 

Uses General-purpose water-repellent coatings or seaiants to prevent galvanic corrosion iubricant for piastics and rubber Gabrosa MV275 [Akzo Nobei bv]... 

Chem. Descrip. Chrome complex sol n. in IPA Uses Water repellent, release agent used on paper/paperboard for water-repellent pkg. materials, food pkg., grease-resistant and release paper when used with PVA, water-repellent coatings and adhesives, water- and stain-resistant leather (shoes, golf bags, etc.), colorfast, water-repellent suede (dry-cleanable) insolubilizer for adhesives, films, protein binders, and inks... 

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