Glass ceramic articles having improved properties and methods for making the same

Patent metadata

Field	Value
Publication number	US-11649187-B2
Application number	US-202117237272-A
Country	US
Kind code	B2
Filing date	Apr 22, 2021
Priority date	Jul 16, 2018
Publication date	May 16, 2023
Grant date	May 16, 2023

Abstract

A glass ceramic article including a lithium disilicate crystalline phase, a petalite crystalline phased, and a residual glass phase. The glass ceramic article has a warp (μm)<(3.65×10 −9 /μm×diagonal 2 ) where diagonal is a diagonal measurement of the glass ceramic article in μm, a stress of less than 30 nm of retardation per mm of glass ceramic article thickness, a haze (%)<0.0994t+0.12 where t is the thickness of the glass ceramic article in mm, and an optical transmission (%)>0.91×10 (2−0.03t) of electromagnetic radiation wavelengths from 450 nm to 800 nm, where t is the thickness of the glass ceramic article in mm.

First claim

What is claimed is:

1. A glass ceramic article comprising:
from 20 wt % to 70 wt % petalite;
from 20 wt % to 60 wt % lithium disilicate; and
from 5 wt % to 50 wt % residual glass, wherein
the glass ceramic article has a thickness from 0.2 mm to 1 mm,
the glass ceramic article has a transmittance of at least 85% of light in a wavelength range from 450 nm to 800 nm, and
the glass ceramic article has a haze of less than 0.2.

2. The glass ceramic article of claim 1 , wherein the glass ceramic article comprises:
from 40 wt % to 70 wt % petalite;
from 40 wt % to 60 wt % lithium disilicate;
less than 3 wt % of other crystalline phases; and
from 10 wt % to 20 wt % residual glass.

3. The glass ceramic article of claim 1 , wherein
the glass ceramic article comprises lithium phosphate, and
at least 80% of phosphate in the glass ceramic article is present as lithium phosphate.

4. The glass ceramic article of claim 1 , wherein a Raman peak height ratio of petalite to lithium phosphate is from 1.1 to 1.3.

5. The glass ceramic article of claim 1 , wherein the glass ceramic article has a warp of less than 110 μm measured on a 156×76 mm sheet.

6. The glass ceramic article of claim 1 , wherein the glass ceramic article has a stress of less than 25 nm of retardation per mm of sheet thickness.

7. The glass ceramic article of claim 1 , wherein the glass ceramic article is a strengthened glass ceramic article and has a fracture toughness that is greater than or equal to 1.0 MPa√m.

8. The glass ceramic article of claim 7 , wherein the fracture toughness is less than or equal to 2.0 MPa√m.

9. The glass ceramic article of claim 1 , wherein the glass ceramic article has a hardness that is greater than 700 kgf.

10. The glass ceramic article of claim 9 , wherein the hardness is less than 750 kgf.

11. The glass ceramic article of claim 1 , wherein the glass ceramic article is a strengthened glass ceramic article and has a compressive stress that is greater than 190 MPa.

12. The glass ceramic article of claim 11 , wherein the compressive stress is less than 250 MPa.

13. The glass ceramic article of claim 1 , wherein the glass ceramic article is a strengthened glass ceramic article and has a central tension that is greater than or equal to 80 MPa.

14. The glass ceramic article of claim 13 , wherein the central tension is less than 180 MPa.

15. The glass ceramic article of claim 1 , wherein the glass ceramic article is a strengthened glass ceramic having a thickness of 0.8 mm and does not fail when dropped on 80 grit sandpaper from a height of 215 cm.

16. A strengthened glass ceramic article comprising:
a thickness from 0.2 mm to 1 mm;
a transmittance of at least 85% of light in a wavelength range from 450 nm to 800 nm;
a haze of less than 0.2;
a fracture toughness that is greater than or equal to 1.0 MPa√m;
a hardness that is greater than 700 kgf;
a compressive stress that is greater than 190 MPa; and
a central tension that is greater than or equal to 80 MPa.

17. The strengthened glass ceramic article of claim 16 , wherein the strengthened glass ceramic article comprises petalite, lithium disilicate, and a residual glass phase.

18. The strengthened glass ceramic article of claim 17 , wherein the strengthened glass ceramic article comprises:
from 40 wt % to 70 wt % petalite;
from 40 wt % to 60 wt % lithium disilicate;
less than 3 wt % of other crystalline phases; and
from 10 wt % to 20 wt % residual glass.

19. The strengthened glass ceramic article of claim 18 , wherein
the strengthened glass ceramic article comprises lithium phosphate, and
at least 80% of phosphate in the glass ceramic article is present as lithium phosphate.

20. The strengthened glass ceramic article of claim 19 , wherein a Raman peak height ratio of petalite to lithium phosphate is from 1.1 to 1.3.

21. The strengthened glass ceramic article of claim 16 , wherein the strengthened glass ceramic article has a warp of less than 110 μm measured on a 156×76 mm sheet.

22. The strengthened glass ceramic article of claim 16 , wherein the strengthened glass ceramic article has a stress of less than 25 nm of retardation per mm of sheet thickness.

23. The strengthened glass ceramic article of claim 16 , wherein the strengthened glass ceramic article has a thickness of 0.8 mm and does not fail when dropped on 80 grit sandpaper from a height of 215 cm.

24. The strengthened glass ceramic article of claim 16 , wherein
the fracture toughness is less than or equal to 2.0 MPa√m,
the hardness is less than 750 kgf,
the compressive stress is less than 250 MPa, and
the central tension is less than or equal to 180 MPa.

Assignees

• Corning Inc

Inventors

• Click Carol Ann
• Edmonston James Howard
• Fu Qiang
• Hall Jill Marie
• Hubert Mathieu Gerard Jacques
• Joshi Dhananjay
• Kittleson Andrew Peter
• Kroemer Katherine Weber
• Moore Galan Gregory
• Rai Rohit
• Ridge John Richard
• Saltzer Jr John Robert
• Smith Charlene Marie
• Stapleton Erika Lynn
• Trosa Matthew Daniel
• Ukrainczyk Ljerka
• Wilson Shelby Kerin
• Yang Bin
• Zheng Zheming

Classifications

• C03C10/0027 Primary

  containing SiO2, Al2O3, Li2O as main constituents · CPC title

• C03C3/097 Primary

  containing phosphorus, niobium or tantalum · CPC title

• C03C21/002

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

• C03C10/0018

  containing SiO2, Al2O3 and monovalent metal oxide as main constituents · CPC title

• B32B2457/00

  Electrical equipment · CPC title