# US 11,306,024 B2 · Textured glass articles and methods of making the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,306,024 B2 - Document ID: US11306024B2 - Status: Granted - Kind: B2 - Application number: 16/886,558 - Filed: 2020-05-28 - Published: 2020-12-03 - Granted: 2022-04-19 - Earliest claimed: 2019-05-30 - Assignees: Corning Incorporated - Applicants: Corning Incorporated - Inventors: Yuhui Jin; Aize Li; Qiao Li; Wei Sun - Web page: https://patentgrep.com/patent/US11306024B2 ## CPC - C03C 21/002: {to perform ion-exchange between alkali ions (C03C21/005 takes precedence)} - C03C 3/085: containing an oxide of a divalent metal - C03C 4/0092: {for glass with improved high visible transmittance, e.g. extra-clear glass} - C03C 15/00: Surface treatment of glass, not in the form of fibres or filaments, by etching (etching or surface-brightening compositions, in general C09K13/00) - C03C 2204/08: Glass having a rough surface - Y10T 428/24355: Continuous and nonuniform or irregular surface on layer or component [e.g., roofing, etc.] - C03C: CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract A glass article is provided that includes: a glass substrate comprising a thickness and a primary surface; and a textured region defined by the primary surface. The textured region comprises a plurality of sub-surface hillocks, each hillock having a top surface and a base, the base located below the primary surface of the substrate. The plurality of hillocks comprises an average lateral feature size from 0.1 μm to 3 μm and an average height from 5 nm to 200 nm. Further, the primary surface of the substrate is substantially planar. ## Claims ### Claim 1 A glass article, comprising: a glass substrate comprising a thickness and a primary surface; and a textured region defined by the primary surface, wherein the textured region comprises a plurality of exposed, sub-surface hillocks, each hillock having a top surface and a base, the base located at a depth below the primary surface of the substrate, wherein the plurality of hillocks comprises an average lateral feature size from 0.1 μm to 3 μm and an average height from 5 nm to 200 nm, wherein the primary surface of the substrate is substantially planar, and further wherein the top surface of each of the hillocks is substantially planar and substantially parallel to the primary surface. ### Claim 2 (depends on 1) The glass article according to claim 1, wherein the plurality of hillocks comprises an average lateral feature size from 0.2 μm to 2 μm. ### Claim 3 (depends on 1) The glass article according to claim 1, wherein each of the hillocks has a mesa-like appearance with the top surface at a depth below the primary surface of the glass substrate and the base substantially round in shape. ### Claim 4 (depends on 1) The glass article according to claim 1, wherein the base of each hillock defines a moat in the primary surface. ### Claim 5 (depends on 1) The glass article according to claim 1, wherein the glass substrate comprises a composition selected from the group consisting of an aluminosilicate glass, a borosilicate glass, a phosphosilicate glass, a soda lime glass, an alkali aluminosilicate glass, and an alkali aluminoborosilicate glass. ### Claim 6 (depends on 1) The glass article according to claim 1, wherein the glass substrate further comprises a compressive stress region that extends from the primary surface to a selected depth, and further wherein the compressive stress region comprises a minimum compressive stress (CS) of 200 MPa and a depth of compression (DOC) from 5 μm to 200 μm. ### Claim 7 A glass article, comprising: a glass substrate comprising a thickness and a primary surface; and a textured region defined by the primary surface, wherein the textured region comprises a plurality of exposed, sub-surface hillocks, each hillock having a top surface and a base, the base located at a depth below the primary surface of the substrate, wherein the plurality of hillocks comprises an average lateral feature size from 0.1 μm to 3 μm and an average height from 5 nm to 200 nm, wherein the glass article comprises a sparkle of less than 1% as measured by pixel power distribution (PPD) with a 140 pixels per inch (PPI) light source, wherein the primary surface of the substrate is substantially planar, and further wherein the top surface of each of the hillocks is substantially planar, and substantially parallel to the primary surface. ### Claim 8 (depends on 7) The glass article according to claim 7, wherein the plurality of hillocks comprises an average lateral feature size from 0.2 μm to 2 μm. ### Claim 9 (depends on 7) The glass article according to claim 7, wherein the glass substrate further comprises a compressive stress region that extends from the primary surface to a selected depth, and further wherein the compressive stress region comprises a minimum compressive stress (CS) of 200 MPa and a depth of compression (DOC) from 5 μm to 200 μm. ### Claim 10 (depends on 7) The glass article according to claim 7, wherein the glass article further comprises a transmittance of at least 90% in the visible spectrum. ### Claim 11 (depends on 7) The glass article according to claim 7, wherein the glass article further comprises a transmittance haze from 0.1% to 10%. ### Claim 12 (depends on 7) The glass article according to claim 7, wherein the glass article further comprises a gloss from 70 to 120, as measured at a 60° incident angle. ### Claim 13 (depends on 7) The glass article according to claim 7, wherein the glass substrate comprises a composition selected from the group consisting of an aluminosilicate glass, a borosilicate glass, a phosphosilicate glass, a soda lime glass, an alkali aluminosilicate glass, and an alkali aluminoborosilicate glass. ### Claim 14 (depends on 7) The glass article according to claim 7, wherein each of the hillocks has a mesa-like appearance with the top surface at a depth below the primary surface of the glass substrate and the base substantially round in shape. ### Claim 15 A method of making a glass article, comprising: providing a glass substrate comprising a thickness and a primary surface; and submerging the glass substrate in a molten etchant bath for an etching duration of 10 minutes to 1000 minutes, the etchant bath at an etching temperature from 350° C. to 500° C., wherein the etchant bath comprises (by weight): (a) 30% to about 48% KNO3; (b) 30% to about 48% NaNO3; (c) 3% to 10% K2CO3 or Na2CO3; and (d) 0.1% to 30% lithium salt, wherein the submerging is conducted to form a textured region in the glass substrate, and the textured region comprises a plurality of exposed, sub-surface hillocks, each hillock having a top surface and a base, the base located at a depth below the primary surface of the substrate, wherein the plurality of hillocks comprises an average lateral feature size from 0.1 μm to 3 μm and an average height from 5 nm to 200 nm, wherein the primary surface of the substrate is substantially planar, and further wherein the top surface of each of the hillocks is substantially planar and substantially parallel to the primary surface. ### Claim 16 (depends on 15) The method according to claim 15, wherein the lithium salt is selected from the group consisting of LiNO3, Li2CO3, Li2SO4 and LiCl. ### Claim 17 (depends on 15) The method according to claim 15, further comprising: heating the glass substrate to a temperature between 200° C. and the etching temperature, wherein the heating step is conducted before the submerging step. ### Claim 18 (depends on 15) The method according to claim 15, wherein the glass article further comprises a sparkle of less than 1% as measured by pixel power distribution (PPD) with a 140 pixels per inch (PPI) light source. ### Claim 19 (depends on 15) The method according to claim 15, wherein the submerging step is further conducted such that the glass substrate further comprises a compressive stress region that extends from the primary surface to a selected depth, and further wherein the compressive stress region comprises a minimum compressive stress (CS) of 200 MPa and a depth of compression (DOC) from 5 μm to 200 μm.