Hypertransparent Nanostructured Superhydrophobic and Surface Modification Coatings

Abstract

Hydrophobic and self-cleaning surfaces have wide applications, including glasses, camera covers, windows, solar panels and high-end finished surfaces. Many existing hydrophobic coatings either have low transmittance, making them unsuitable for high light transmission applications, or are insufficiently hydrophobic. The present invention concerns high-quality hypertransparent superhydrophobic coatings, for example SiO 2 -based, with double-roughness microstructure that were deposited on to, for example, glass substrates using, for example, the combustion chemical vapor deposition (CCVD) technique. Embodiments of the invention include coatings with a contact angle of higher than 165°, a rolling angle of <5°, a haze of <0.5%, and an increased transmittance by 2% higher and a reflectance of 2% lower than bare glass. The double roughness can improve wear resistance. Additionally, other surface chemistries can be applied to yield hydrophilic, oliophobic, or oliophobic surfaces.

1 . A product with a nanostructured inorganic-based hypertransparent interfacial modifying coating on at least one surface, with a light transmission or reflection similar to or higher than that of the uncoated surface. 
     
     
         2 . The product of  claim 1  where said coating is a hydrophobic coating, with a contact angle greater than 130°. 
     
     
         3 . The product of  claim 1  where said coating is a nanostructured inorganic-based hypertransparent hydrophobic coating, with a contact angle greater than 145°. 
     
     
         4 . The product of  claim 1  where said coating is a nanostructured inorganic-based hypertransparent hydrophobic coating on glass, with a contact angle greater than 160°. 
     
     
         5 . The product of  claim 1  where said coating is a nanostructured inorganic-based hypertransparent hydrophobic coating on glass, with a contact angle greater than 170°. 
     
     
         6 . A method using a vapor deposition technique for making the coating of  claims 1 ,  2 ,  3 ,  4 , or  5 . 
     
     
         7 . The coating of  claim 1  wherein said nanostructured inorganic-based hypertransparent interfacial modifying coating is silica-based. 
     
     
         8 . The products of  claim 1  wherein light is required to pass through said coating. 
     
     
         9 . The products of  claim 1  wherein the light transmission through said coating is increased at least 1% compared to the substrate prior to coating. 
     
     
         10 . The products of  claim 1  wherein the light transmission through said coating is increased at least 2% compared to the substrate prior to coating. 
     
     
         11 . A method for coating a substrate with a nanostructured SiO 2 -containing layer such that the substrate has similar or higher light transmission than the uncoated substrate and haze of less than 5%. 
     
     
         12 . A method of  claim 11  where combustion chemical vapor deposition (CCVD) is used to coat the substrate. 
     
     
         13 . A coating prepared by the method of  claim 12  such that the substrate has >1% higher light transmission than the uncoated substrate. 
     
     
         14 . A coating prepared by the method of  claim 12  such that the substrate has >3% higher light transmission than the uncoated substrate. 
     
     
         15 . The coating of  claim 1  which is wear-resistant surface with at least 90% of the surface area being nanostructured and the surface having an undulating surface of denser, more abrasion-resistant material. 
     
     
         16 . The wear-resistant surface of  claim 15  with at least 99% of the surface area being nanostructured and the surface having an undulating surface of denser, more abrasion-resistant material. 
     
     
         17 . The coating of  claim 13  which is wear-resistant surface with at least 90% of the surface area being nanostructured and the surface having an undulating surface of denser, more abrasion-resistant material. 
     
     
         18 . The wear-resistant surface of  claim 17  with at least 99% of the surface area being nanostructured and the surface having an undulating surface of denser, more abrasion-resistant material. 
     
     
         19 . The surface of  claim 1  where the surface is oliophobic with at least 130 degree contact angle to many oils. 
     
     
         20 . The surface of  claim 1  where the surface is hydrophilic with at less than 10 degree contact angle. 
     
     
         21 . The surface of  claim 1  where the substrate is not transparent. 
     
     
         22 . The surface of  claim 19  where the surface is also hydrophobic to at least 130 degrees contact angle.