Superhydrophobic and dust mitigating coatings

Patent metadata

Field	Value
Publication number	US-10786830-B1
Application number	US-201816215040-A
Country	US
Kind code	B1
Filing date	Dec 10, 2018
Priority date	Sep 30, 2014
Publication date	Sep 29, 2020
Grant date	Sep 29, 2020

Abstract

A system, apparatus, composition and method employing a dust mitigation coating that also mitigates or repels water, ice, and other liquids. Techniques to coat the surfaces of equipment and items with these dust, liquid, and ice mitigation coatings, minimizing or eliminating mission problems caused by dust, liquid, or ice accumulation, particularly in outer space or on another planetary body or moon. Further, the dust mitigation coatings should exhibit a Lotus-like effect, making the coated surfaces ultra-hydrophobic. The present invention is also directed to techniques for improving the functioning of terrestrial-based equipment and systems where dust, liquid, or ice accumulation is a problem, such as in hospitals and other health contexts to prevent contamination.

First claim

What is claimed is:

1. A method of applying a hydrophobic dust mitigating transparent coating to a bare glass substrate; said method comprising the steps of:
mixing a nano-texture epoxy basecoat by mixing 0.66 g of silica nanoparticles with an 8:1 ratio of 15 nm particles to 80 nm particles by mass, with 0.4 ml of 4-to-1 epoxy resin wherein said resin includes about 80% oxirane, 2,2′-[(1-methylethylidene)bis(4,1-phenyleneoxymethylene)]bis-, homopolymer and at least 10% aliphatic glycidyl ether, with 0.1 ml of 4-to-1 epoxy hardener wherein said hardener includes 55-65% formaldehyde-phenol-triethylenetetramine copolymer and 15-20% triethylenetetramine and 15-20% Phenol, and 50 ml acetone;
cleaning said bare glass substrate without an application of a primer layer by using soap and distilled water and thereafter rinsing said bare glass substrate in acetone;
applying said nano-texture epoxy basecoat to said bare glass substrate by rubbing the nano-texture epoxy basecoat using a first set of lint-free nonwoven cotton wipes on to the surface of the bare glass substrate and allowing said nano-texture epoxy basecoat to flash off and turn matte in appearance and thereafter using a second set of dry lint-free nonwoven cotton wipes to thin out and render said nano-texture epoxy basecoat transparent;
baking said glass substrate and said nano-texture epoxy basecoat at a temperature of 100° C. for 30 minutes to allow the coating to cure and set;
applying a self-assembling monolayer to said nano-texture epoxy basecoat by submerging the glass substrate with the nano-texture epoxy basecoat in a self-assembling monolayer solution consisting of 200-proof ethanol and 0.4% 1H,1H,2H,2H-perfluorodecyltriethoxysilane by volume for at least 16 hours and thereafter removing said solution;
rinsing said self-assembling monolayer with 200-proof ethanol and thereafter blow drying with air;
then baking the dry coated glass substrate with the nano-texture epoxy basecoat and self-assembling monolayer in air at a temperature of 100° C. for 30 minutes thereby forming an aligned hydrophobic layer; and
placing said glass substrate with the nano-texture epoxy basecoat and aligned hydrophobic layer in a vacuum deposition chamber and coating said aligned hydrophobic layer with 100 nm of fluorinated ethylene propylene under 10 −5 Torr at a deposition rate of 19 μg/cm 2 , whereby said method produces a transparent coating such that contacting water forms droplets having contact angles averaging 144°.

Assignees

• Nasa
• United States of America by the Administrator of NASA

Inventors

• Straka Sharon A
• Hasegawa Mark M
• O'Connor Kenneth M
• Stotzer Victoria J

Classifications

• C09D163/00

  Coating compositions based on epoxy resins; Coating compositions based on derivatives of epoxy resins · CPC title

• C08K2201/014

  Additives containing two or more different additives of the same subgroup in C08K · CPC title

• C08K2201/011

  Nanostructured additives · CPC title

• C08K2201/005

  Additives being defined by their particle size in general · CPC title

• C03C2217/76

  Hydrophobic and oleophobic coatings · CPC title