Glass, water-repellent films

The same reaction is found to occur with cotton cloth and with wood, and in a less pronounced way with wool, silk, leather, and many other materials. Glass and other ceramic surfaces also react readily with the methylchlorosilane vapor to give very effective water-repellent films,2 but only if the surface had upon it an adsorbed film of water. Completely dry glass, baked out under vacuum, does not become distinctly water-repellent upon treatment. Glass which has stood at ordinary room conditions usually has on its surface a film of... 

Dimethicones of various viscosities are widely used in cosmetic and pharmaceutical formulations. In topical oil-in-water emulsions dimethicone is added to the oil phase as an antifoaming agent. Dimethicone is hydrophobic and is also widely used in topical barrier preparations. Therapeutically, dimethicone may be used with simethicone in oral pharmaceutical formulations used in the treatment of flatulence. Dimethicone is also used to form a water-repellent film on glass containers. See Table I. 

Uses Qleophobic treatment providing water-repellent film coating for glass and ceramics, e.g., laboratory glassware, optical fibers, clinical analysis, glass plate and glazing... 

Fluoroalkylmethylslloxane, chlorinated Polydimethylslloxane, chlorinated coating, water-repellent film glass plating Aquaphohe CM ... 

Uses Lubricant for plastic or rubber devices and instruments inert protective coating and water-repellent film on skin hydrophobic surf, on glass and ceramic substrates defoamer for aq. and nonaq. liqs. 

Besides such electrical applications as water-repellent surface films, there are many applications where water repellency is an end in itself. Treated glass windowpanes or windshields are not wet by muddy water, and so they stay clean longer and are easier to clean whenever washing is required. Rain docs not flood the surface of a treated windshield but stands in small droplets when the car is in motion the air stream blows the droplets off, leaving the glass clear. Treated tumblers are easier to wash and dry treated chemical glassware holds water with a flat meniscus treated vitreous enamel does not stain easily and has improved luster. Cloth and paper may be made water-repellent for protection against rain, and it is possible that all clothes could be so treated. 

Chem. Descrip. Reactive silicone polymer sol n. in I PA Uses Water repellent for masonry and wood coatings film-former for mold release coatings surfactant for PVC foam antifog coatings for glass... 

The water-repellent coating film is produced by the following procedure. After sol-gel derived Si02 intermediate film having the thickness of 100 nm is applied on the clean surface of the glass substrate, two or three layers of FAS (RfSi(NCO)3) and RS (-(Si(CH3)20) -(Si(CH3)(Rf)0)TO-(Si(CH3)(X)) -) are applied and cured at room temperature. 

The weatherability and abrasion resistance of the new water-repellent glass are derived by the chemical stability of the coating materials, high amount of the FAS and RS film due to the high surface concentration of silanol group at the intermediate Si02 layer and the formation of stable siloxane bonding between FAS and the intermediate layer. 

Yoneda T., Morimoto T. Mechanical durability of water repellent glass. Thin Solid Films 1999 351 279-283... 

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