Shaped glass articles and methods for forming the same

• US 10,377,656 B2
• Filed: 05/07/2015
• Issued: 08/13/2019
• Est. Priority Date: 05/07/2014
• Status: Active Grant

• Current Assignee: Corning Incorporated
• Original Assignee: Corning Incorporated
• Inventors: Dannoux, Thierry Luc Alain, Golyatin, Vladislav Yuryevich, Ridge, John Richard, Ukrainczyk, Ljerka, Vaddi, Butchi Reddy, Venkataraman, Natesan
• Primary Examiner(s): Ewald, Maria V
• Assistant Examiner(s): Davis, Zachary M
• Application Number:
  US15/309,068
• Publication Number:
  US 20170121209A1
• Time in Patent Office: 1,559 Days
• Field of Search: 65106, 65107
• CPC Class Codes: B32B 17/06 comprising glass as the main or only constituent of a layer, next to another layer of a specific material
• CPC Class Codes: B32B 3/00 Layered products comprising a layer with external or internal discontinuities or unevennesses, or a layer of non-planar shape; Layered products comprising a layer having particular features of form
• CPC Class Codes: C03B 17/02 Forming molten glass coated with coloured layers; Forming molten glass of different compositions or layers; Forming molten glass comprising reinforcements or inserts
• CPC Class Codes: C03B 17/064 by the overflow downdraw fusion process; Isopipes therefor
• CPC Class Codes: C03B 23/023 by bending
• CPC Class Codes: C03B 23/0357 by suction without blowing, e.g. with vacuum or by venturi effect
• CPC Class Codes: C03C 21/002 to perform ion-exchange between alkali ions C03C21/005 takes precedence
• CPC Class Codes: H05K 5/066 sealed by fusion of the joining parts without bringing material; sealed by brazing
• CPC Class Codes: Y02P 40/57 Improving the yield, e-g- reduction of reject rates

Abstract

A method includes contacting a second layer of a glass sheet with a forming surface to form a shaped glass article. The glass sheet includes a first layer adjacent to the second layer. The first layer includes a first glass composition. The second layer includes a second glass composition. An effective viscosity of the glass sheet during the contacting step is less than a viscosity of the second layer of the glass sheet during the contacting step. A shaped glass article includes a first layer including a first glass composition and a second layer including a second glass composition. A softening point of the first glass composition is less than a softening point of the second glass composition. An effective 10^8.2 P temperature of the glass article is at most about 900° C.

Claims

1. A shaped glass article comprising:

a first layer comprising a first glass composition comprising an alkali metal oxide selected from the group consisting of Li₂O, Na₂O, K₂O, and combinations thereof; and

a second layer comprising a second glass composition;

wherein a softening point of the first glass composition is less than a softening point of the second glass composition, an effective 10^8.2 P temperature of the glass article is at most about 900°

C., and a viscosity of the second glass composition is at least about 10^8.3 P at the effective 10^8.2 P temperature of the glass article, and wherein the glass article comprises at least one of a surface roughness of at most about 1 nm as measured in accordance with ASTM F2791 and a waviness of at most about 50 nm as measured in accordance with ASTM C1652/C1652M.

2. The glass article of claim 1, wherein the glass article comprises a surface roughness of at most about 1 nm as measured in accordance with ASTM F2791 and a waviness of at most about 50 nm as measured in accordance with ASTM C1652/C1652M.

3. The glass article of claim 1, wherein the first glass composition comprises a higher average coefficient of thermal expansion (CTE) than the second glass composition.

4. The glass article of claim 1, wherein the second layer comprises a compressive stress of at least about 100 MPa.

5. The glass article of claim 1, wherein the effective 10^8.2 P temperature of the glass article is at most about 875°

C.

6. The glass article of claim 1, further comprising at least one bend with a radius of less than about 5 mm.

7. The glass article of claim 1, wherein:

at least one of the first glass composition or the second glass composition is ion exchangeable;

or

at least one of the first layer or the second layer is ion exchanged.

8. The glass article of claim 1, wherein the second glass composition is substantially free of alkali metal.

9. The glass article of claim 1, wherein the first layer comprises a core layer, and the second layer comprises a first cladding layer adjacent to a first major surface of the core layer and a second cladding layer adjacent to a second major surface of the core layer opposite the first major surface.

10. A display, an automotive glazing, or an architectural panel comprising the glass article of claim 1.