Highly durable hydrophobic coatings and methods

Abstract

Substrates have a hydrophobic surface coating comprised of the reaction products of a chlorosilyl group containing compound and an alkylsilane. Most preferably the substrate is glass. In one preferred form of the invention, highly durable hydrophobic coatings may be formed by forming a silicon oxide anchor layer or hybrid organo-silicon oxide anchor layer from a humidified reaction product of silicon tetrachloride or trichloromethylsilane, followed by the vapor-deposition of a chloroalkylsilane. Such a silicon oxide anchor layer will advantageously have a root mean square surface roughness of less than about 6.0 nm (preferably less than about 5.0 nm) and a low haze value of less than about 3.0% (preferably less than about 2.0%). Another embodiment of the present invention include the simultaneous humidified vapor deposition of a chlorosilyl group containing compound and a chloroalkylsilane. Specifically, in certain preferred embodiments, the simultaneous vapor deposition onto a glass substrate of silicon tetrachloride (SiCl4) and dimethyldichlorosilane (DMDCS) results in a hydrophobic coating comprised of cross-linked polydimethylsiloxane (PDMSO), which may then be capped with a fluoroalkylsilane (FAS). The cross-linked PDMSO layer may be formed on the surface of the glass substrate, or a silicon oxide anchor layer may be deposited under the cross-linked (PDMSO) layer. SiCl4, trimethylchlorosilane (TMCS), trichloromethylsilane and combinations of these silanes therein may also be simultaneously vapor deposited onto a substrate surface so as to achieve hydrophobic coatings of exceptional durability.

Dependencies are inferred from the claim text.