Antireflective synthetic brochosomal coatings

Patent metadata

Field	Value
Publication number	US-10890690-B2
Application number	US-201815946004-A
Country	US
Kind code	B2
Filing date	Apr 5, 2018
Priority date	Apr 5, 2017
Publication date	Jan 12, 2021
Grant date	Jan 12, 2021

Abstract

Synthetic brochosomes can be prepared by disposing a monolayer of first polymer microspheres on a substrate and forming a layer of metal on the monolayer of the first polymer microspheres. A monolayer of second polymer microspheres is then disposed on the layer of metal to form a template. The second polymer microspheres are smaller than the first polymer microspheres. A brochosome material is then electrodeposited on the template. The brochosome material is selected from the group consisting of a metal, a metal oxide, a polymer or a hybrid thereof. The first polymer microspheres and the second polymer microspheres are then removed to form a coating of synthetic brochosomes of the brochosome material on the substrate.

First claim

What is claimed is:

1. A layer comprising a plurality of interconnected synthetic brochosomes, the synthetic brochosomes comprising:
a spherical portion having an interior surface, the interior surface having a shape that is at least a portion of a first sphere having a first diameter; and
a plurality of outgrowths that define a plurality of indentations, the plurality of outgrowths having size and shape consistent with deposition growth that is radially outward from the interior surface and around a plurality of removable structures, the plurality of indentations having a shape that is a negative imprint of one of the plurality of removable structures, the plurality of indentations each having a second diameter,
wherein the second diameter is smaller than the first diameter,
wherein the spherical portion is formed of a material that is capable of receiving an electrodeposition-compatible material,
wherein the plurality of outgrowths are formed of the electrodeposition-compatible material.

2. The layer of claim 1 , wherein the first diameter is in a range from 1 μm to 10 μm.

3. The layer of claim 1 , wherein the second diameter is in a range from 100 nm to 1 μm.

4. The layer of claim 1 , wherein the plurality of indentations form a honeycomb pattern.

5. The layer of claim 1 , wherein a ratio of the second diameter to the first diameter is less than 0.35.

6. The layer of claim 1 , wherein the spherical portion has a first radius, and the sphere has a second radius,
wherein the first radius is less than 9 times a predetermined wavelength of light, and the first radius is greater than 1.4 times the predetermined wavelength of light, and
wherein the second radius is less than 2 times the predetermined wavelength of light, and the second radius is greater than 0.5 times the predetermined wavelength of light.

7. The layer of claim 6 , wherein the predetermined wavelength of light falls within at least one of the following regions:
ultraviolet light region;
visible light region; or
near infrared light region.

8. The synthetic brochosome of claim 1 , wherein adjacent indentations define a protrusion of the coating.

9. An antireflective coating comprising:
a substrate; and
the layer of claim 1 disposed on the substrate
wherein the layer is a monolayer.

10. The antireflective coating of claim 9 , wherein the coating has a reflectance of less than 10% at a wavelength in a range from 250 nm to 2000 nm.

11. The antireflective coating of claim 7 , wherein the synthetic brochosomes are arranged to form a pattern, the pattern being substantially a honeycomb pattern.

Assignees

• Penn State Res Found

Inventors

• Wong Tak-Sing
• Yang Shikuan
• Sun Nan
• Boschitsch Birgitt

Classifications

• C25D13/06

  with polymers {(not used, see C09D5/44)} · CPC title

• C25D5/605

  Surface topography of the layers, e.g. rough, dendritic or nodular layers · CPC title

• B22F1/18

  Non-metallic particles coated with metal · CPC title

• G02B1/118

  having sub-optical wavelength surface structures designed to provide an enhanced transmittance, e.g. moth-eye structures · CPC title

• B22F1/05

  Metallic powder characterised by the size or surface area of the particles · CPC title