Textured glass surfaces for reduced electrostatic charging

Patent metadata

Field	Value
Publication number	US-2020407274-A1
Application number	US-201916977176-A
Country	US
Kind code	A1
Filing date	Mar 5, 2019
Priority date	Mar 7, 2018
Publication date	Dec 31, 2020
Grant date	—

Abstract

A substrate with a textured surface is disclosed. The textured glass substrate exhibits low haze and a significant reduction in contact electrostatic charging when compared to an un-textured but otherwise identical glass substrate. Methods of producing the textured surface by an in situ mask etching process are also disclosed.

First claim

1 . A glass substrate comprising a chemically treated major surface, the glass substrate comprising a haze value equal to or less than about 1% and, when compared to an untreated otherwise identical glass substrate, further comprises an improvement in ESC performance of greater than 70% when subjected to a Lift Test performed on the chemically treated major surface.

2 . The glass substrate according to claim 1 , wherein the glass substrate further comprises an improvement in transmittance of greater than 0.25% over a wavelength range from 350 nm to 400 nm when compared to the untreated otherwise identical glass substrate.

3 . The glass substrate according to claim 1 , wherein the glass substrate is a chemically strengthened glass substrate.

4 . The glass substrate according to claim 1 , wherein the glass substrate is a laminated glass substrate comprising a first glass layer with a first coefficient of thermal expansion, and a second glass layer fused to the first glass layer and comprising a second coefficient of thermal expansion different from the first coefficient of thermal expansion.

5 . The glass substrate according to claim 1 , wherein the chemically treated major surface comprises a plurality of raised features, and an average feature density of the raised features is in a range from about 0.2 features/μm 2 to about 1 features/μm 2 .

6 . The glass substrate according to claim 5 , wherein an average feature volume of the raised features is in a range from about 0.014 μm 3 to about 0.25 μm 3 .

7 . The glass substrate according to claim 5 , wherein a total surface area of the raised features relative to the total surface area of the chemically treated major surface is in a range from about 4% to about 35%.

8 . The glass substrate according to claim 1 , wherein an average surface roughness Ra of the chemically treated major surface is in a range from about 0.4 nanometers to about 10 nanometers.

9 . A method of forming a textured glass substrate comprising:
treating a major surface of a glass substrate with an etchant comprising acetic acid in an amount from about 50 wt % to about 60 wt %, ammonium fluoride in an amount from about 10 wt % to about 25 wt %, and water in an amount from about 20 wt % to about 35 wt %.

10 . The method according to claim 9 , wherein during the treating the major surface of the glass substrate is exposed to the etchant for a time less than about 30 seconds.

11 . The method according to claim 10 , wherein during the treating the glass substrate is at a temperature in a range from about 18° C. to about 60° C.

12 . The method according to claim 9 , wherein an average surface roughness Ra of the major surface after the treating is in a range from about 0.4 nanometers to about 10 nanometers.

13 . The method according to claim 9 , wherein after the treating, the glass substrate exhibits a total haze value less than 1% and, when compared to an untreated but otherwise identical glass substrate, exhibits an increase in ESC performance greater than 70% when subjected to a Lift Test performed on the chemically treated major surface.

Assignees

• Corning Inc

Inventors

• Agnello Gabriel Pierce
• Jing He
• Wolcott Christine Coulter

Classifications

• B32B17/06 Primary

  comprising glass as the main or only constituent of a layer, next to another layer of a specific {material} · CPC title

• C03C23/00

  Other surface treatment of glass not in the form of fibres or filaments · CPC title

• B32B17/10064

  comprising at least two glass sheets, only one of which being an outer layer · CPC title

• C03C21/002 Primary

  to perform ion-exchange between alkali ions (C03C21/005 takes precedence) · CPC title

• C03C15/00 Primary

  Surface treatment of glass, not in the form of fibres or filaments, by etching (etching or surface-brightening compositions, in general C09K13/00) · CPC title