Oleophobic coatings for glass structures in electronic devices

Patent metadata

Field	Value
Publication number	US-11921259-B2
Application number	US-202016843137-A
Country	US
Kind code	B2
Filing date	Apr 8, 2020
Priority date	Apr 17, 2019
Publication date	Mar 5, 2024
Grant date	Mar 5, 2024

Abstract

An electronic device includes electrical components in a housing. The components may include optical components such as a display. Protective structures may be used to protect the optical components. The protective structures may include one or more protective transparent layers such as layers of glass or crystalline material such as sapphire. The protective transparent layers may be coated with an oleophobic coating. To enhance coating durability, catalyst may be used to help bond the oleophobic coating. An adhesion promotion layer such as a silicon oxide layer may be deposited on the transparent protective layer. A catalyst layer such as a layer of sodium fluoride may be deposited on the adhesion promotion layer. The oleophobic material may be evaporated or otherwise deposited on the catalyst layer. Heat and moisture may help the oleophobic material form chemical bonds with the adhesion promotion layer, thereby forming a durable oleophobic coating.

First claim

What is claimed is:

1. A method, comprising:
depositing an adhesion promotion layer onto a protective transparent layer;
depositing a catalyst layer onto the adhesion promotion layer;
depositing oleophobic material onto the catalyst layer; and
curing the oleophobic material to form an oleophobic coating layer that is chemically bonded to the protective transparent layer.

2. The method defined in claim 1 wherein depositing the adhesion promotion layer comprises depositing a silicon oxide layer onto the protective transparent layer.

3. The method defined in claim 2 wherein depositing the catalyst layer comprises depositing a layer of sodium fluoride onto the adhesion promotion layer.

4. The method defined in claim 3 wherein depositing the oleophobic material comprises depositing fluoropolymer.

5. The method defined in claim 4 wherein depositing the fluoropolymer comprises evaporating perfluoropolyether.

6. The method defined in claim 5 wherein depositing the silicon oxide layer comprises depositing the silicon oxide layer by evaporation and wherein depositing the layer of sodium fluoride comprises depositing the layer of sodium fluoride by evaporation.

7. The method defined in claim 5 wherein the curing comprises exposure of the oleophobic material to moisture.

8. The method defined in claim 7 wherein the curing comprises exposure of the oleophobic material to a temperature of at least 100° C. to form Si—O—Si chemical bonds.

9. The method defined in claim 8 further comprising spraying the oleophobic material with water to remove sodium.

10. A method of forming an oleophobic coating on a transparent protective layer for an electronic device, comprising:
cleaning the transparent protective layer;
evaporating a layer of silicon oxide onto a surface of the cleaned transparent protective layer;
evaporating a catalyst layer onto the layer of silicon oxide; and
depositing fluoropolymer onto the catalyst layer.

11. The method defined in claim 10 wherein evaporating the catalyst layer comprises evaporating a sodium fluoride catalyst layer onto the layer of silicon oxide.

12. The method defined in claim 11 wherein depositing the fluoropolymer comprises evaporating perfluoropolyether onto the catalyst layer.

13. The method defined in claim 12 further comprising curing the deposited fluoropolymer in the presence of the sodium fluoride catalyst layer to chemically bond the oleophobic coating to the transparent protective layer.

14. The method defined in claim 13 wherein the fluoropolymer comprises a silane coupling group.

Assignees

• Apple Inc

Inventors

• Mittal Manish
• Liu Feng
• Ishizeki Kenji
• Rogers Matthew S
• Matsuyuki Naoto
• Oetting Wolf

Classifications

• G02B1/18 Primary

  Coatings for keeping optical surfaces clean, e.g. hydrophobic or photo-catalytic films (G02B1/16 takes precedence) · CPC title

• B05D1/36

  Successively applying liquids or other fluent materials, e.g. without intermediate treatment · CPC title

• B05D1/60

  Deposition of organic layers from vapour phase (vapour phase deposition in general C23C14/00, C23C16/00) · CPC title

• B05D5/083

  involving the use of fluoropolymers · CPC title

• C03C17/42

  at least one coating of an organic material and at least one non-metal coating · CPC title