ARTICLES HAVING RETAINED STRENGTH

• US 20140106146A1
• Filed: 10/11/2013
• Published: 04/17/2014
• Est. Priority Date: 10/12/2012
• Status: Active Grant

• Current Assignee: Corning Incorporated
• Original Assignee: Corning Incorporated
• Inventors: Hart, Shandon Dee, Price, James Joseph, Saha, Chandan Kumar, Decker, Heather Bossard, Hu, Guangli, Li, Fei
• Granted Patent: US 10,487,009 B2
• Time in Patent Office: Days
• US Class Current: 428/210
• CPC Class Codes: C03C 17/34 with at least two coatings having different compositions C03C17/44 takes precedence
• CPC Class Codes: C03C 17/3417 all coatings being oxide coatings
• CPC Class Codes: C03C 17/3435 comprising a nitride, oxynitride, boronitride or carbonitride
• CPC Class Codes: C03C 17/36 at least one coating being a metal
• CPC Class Codes: C03C 17/38 at least one coating being a coating of an organic material
• CPC Class Codes: C03C 17/42 at least one coating of an organic material and at least one non-metal coating
• CPC Class Codes: C03C 21/002 to perform ion-exchange between alkali ions C03C21/005 takes precedence
• CPC Class Codes: C03C 2217/425 consisting of a porous layer
• CPC Class Codes: C03C 2217/948 Layers comprising indium tin oxide [ITO]
• CPC Class Codes: G06F 3/03 Arrangements for converting the position or the displacement of a member into a coded form
• CPC Class Codes: Y10T 428/24851 Intermediate layer is discontinuous or differential
• CPC Class Codes: Y10T 428/24926 including ceramic, glass, porcelain or quartz layer
• CPC Class Codes: Y10T 428/2495 Thickness [relative or absolute]
• CPC Class Codes: Y10T 428/24975 No layer or component greater than 5 mils thick
• CPC Class Codes: Y10T 428/24983 Hardness
• CPC Class Codes: Y10T 428/24996 With internal element bridging layers, nonplanar interface between layers, or intermediate layer of commingled adjacent foam layers
• CPC Class Codes: Y10T 428/24999 Inorganic

Abstract

One or more aspects of the disclosure pertain to an article including a film disposed on a glass substrate, which may be strengthened, where the interface between the film and the glass substrate is modified, such that the article retains its average flexural strength, and the film retains key functional properties for its application. Some key functional properties of the film include optical, electrical and/or mechanical properties. The bridging of a crack from one of the film or the glass substrate into the other of the film or the glass substrate can be prevented by inserting a crack mitigating layer between the glass substrate and the film.

Claims

1. An article comprising:

a glass substrate having opposing major surfaces having a first average strain-to-failure;

a crack mitigating layer disposed on a first major surface;

a film disposed on the crack mitigating layer having a second average strain-to-failure that is less than the first average strain-to-failure,

wherein the crack mitigating layer prevents cracks originating in one of the film or the glass substrate from bridging to the other of the film or the glass substrate.

2. The article of claim 1, wherein the film comprises functional properties selected from one or more of optical properties, electrical properties and mechanical properties, and wherein the film retains substantially the same functional properties when the crack mitigating layer is disposed between the glass substrate and the film.

3. The article of claim 1, wherein the crack mitigating layer exhibits a first critical strain energy release rate (G_IC=K_IC²/E) and the film exhibits a second critical strain energy release rate (G_IC=K_IC²/E) that is less than the first critical strain energy release rate.

4. The article of claim 1, wherein the crack mitigating layer has a third average strain-to-failure, and wherein the second average strain-to-failure is less than the first average strain-to-failure and the third average strain-to-failure.

5. The article of claim 1, wherein the first average strain-to-failure is greater than an amount selected from 0.5%, 0.7%, 1.0%, 1.5% and 2%.

6. The article of claim 3, wherein the first critical strain energy release rate (G_IC=K_IC²/E) is about 0.1 kJ/m² or greater, and wherein the second critical strain energy release rate (G_IC=K_IC²/E) is less than about 0.1 kJ/m².

7. The article of claim 1, wherein the crack mitigating layer comprises one or more of porous oxides, porous nitrides, porous carbides, porous semi-conductors, porous hybrid organic-inorganic materials, and porous or nonporous polymeric materials.

8. The article of claim 4, wherein the crack mitigating layer has a yield stress of less than about 500 MPa.

9. The article of claim 1, wherein the crack mitigating layer has an elastic modulus of about 50 GPa or less.

10. The article of claim 9, wherein the film has an elastic modulus of about 25 GPa or more.

11. The article of claim 10, wherein the film has a hardness of about 2 GPa or more.

12. The article of claim 2, wherein the film comprises one or more layers selected from transparent conductive oxide layers, IR reflecting layers, UV reflecting layers, conducting layers, semiconducting layers, electronics layers, thin film transistor layers, EMI shielding layers, anti-reflection layers, anti-glare layers, dirt-resistant layers, self-cleaning layers, scratch-resistant layers, barrier layers, passivation layers, hermetic layers, diffusion-blocking layers, and fingerprint-resistant layers.

13. The article of claim 12, wherein the one or more transparent conductive oxide layers comprises indium-tin-oxide.

14. The article of claim 13, wherein the crack mitigating layer comprises polyimide and the functional properties of the film comprise electrical conductivity.

15. The article of claim 1, wherein the glass substrate has an average flexural strength that is maintained when the crack mitigating layer is disposed on the first major surface and the film is disposed on the crack mitigating layer.

16. The article of claim 1, wherein the glass substrate has a first refractive index, the crack mitigating layer has a second refractive index greater than the first refractive index, and the film has a third refractive index greater than the second refractive index.

17. The article of claim 1, further comprising an additional film disposed on the glass substrate, the additional film comprising one or more of a protective layer, an adhesive layer, a planarizing layer, an anti-splintering layer, an optical bonding layer, a display layer, a polarizing layer, and a light-absorbing layer.

18. The article of claim 17, wherein the article has a total reflectivity of 10.0% or less over the visible wavelength range from about 450 nm to about 650 nm.

19. The article of claim 5, wherein the glass substrate is strengthened or strong.

20. An article comprising:

a glass substrate having opposing major surfaces;

a crack mitigating layer disposed on a first major surface having a first critical strain energy release rate (G_IC=K_IC²/E); and

a film disposed on the crack mitigating layer having a second critical strain energy release rate (G_IC=K_IC²/E) that is less than the first critical strain energy release rate,

wherein the crack mitigating layer increases the average flexural strength of the article, when compared to an article comprising the glass substrate and the film but not the crack mitigating layer.

21. The article of claim 20, wherein the film has a fracture toughness of less than about 10 MPa·

m^1/2 and the crack mitigating layer has a fracture toughness of 1 MPa·

m^1/2 or greater.

22. The article of claim 20, wherein the crack mitigating layer comprises one or more of porous oxides, porous nitrides, porous carbides, porous semi-conductors, porous hybrid organic-inorganic materials and porous and nonporous polymeric materials.

23. The article of claim 22, wherein the crack mitigating layer has a yield stress of less than about 500 MPa.

24. The article of claim 22, wherein the crack mitigating layer has an elastic modulus of about 50 GPa or less.

25. The article of claim 24, wherein the film has an elastic modulus of about 25 GPa or more.

26. The article of claim 24, wherein the film has a hardness of about 2 GPa or more.

27. The article of claim 20, wherein the film comprises one or more layers selected from transparent conductive oxide layers, IR reflecting layers, UV reflecting layers, conducting layers, semiconducting layers, electronics layers, thin film transistor layers, anti-reflection layers, anti-glare layers, dirt-resistant layers, self-cleaning layers, scratch-resistant layers, barrier layers, passivation layers, hermetic layers, diffusion-blocking layers, and fingerprint-resistant layers.

28. The article of claim 27, wherein the film comprises one or more transparent conductive oxide layers, the one or more transparent conductive oxide layers comprising indium-tin-oxide.

29. The article of claim 28, wherein the crack mitigating layer comprises polyimide.

30. The article of claim 29, further exhibiting an average strain-to-failure that is greater than the average strain-to-failure of an article comprising the glass substrate and the film but not the crack mitigating layer.

31. The article of claim 22, wherein the glass substrate has a first refractive index, the crack mitigating layer has a second refractive index greater than the first refractive index, and the film has a third refractive index greater than the second refractive index.

32. The article of claim 22, further comprising an additional film disposed on the glass substrate, the additional film comprising a protective layer, an adhesive layer, a planarizing layer, an anti-splintering layer, an optical bonding layer, a display layer, a polarizing layer, or a light-absorbing layer.

33. The article of claim 32, wherein the article has a total reflectivity of about 10.0% or less over the visible wavelength range from about 450 nm to about 650 nm.

34. The article of claim 20, wherein the glass substrate is strengthened or strong and has an average strain-to-failure in the range from about 0.5% to about 2%.

35. A touch sensor device comprising:

a glass substrate having opposing major surfaces;

a crack mitigating layer disposed on a first major surface; and

a film comprising a transparent conductive oxide disposed on at least a portion of the crack mitigating layer to form film coated regions and uncoated regions without the film,

wherein the coated regions have a coated total reflectance and the uncoated regions have an uncoated total reflectance that differ by about 5.0% or less across a visible wavelength range from about 450 nm to about 650 nm, and

wherein the crack mitigating layer prevents cracks originating in one of the film or the glass substrate from bridging to the other of the film or the glass substrate.

36. The touch sensor device of claim 35, wherein the glass substrate is strengthened or strong and has an average strain-to-failure in the range from about 0.5% to about 2%.

37. A method of forming an article comprising:

providing a glass substrate having opposing major surfaces and an average flexural strength;

disposing a crack mitigating layer on a first major surface, the crack mitigating layer having a first thickness;

disposing a film having a second thickness and one or more functional properties on the crack mitigating layer, such that the crack mitigating layer is disposed between the film and the glass substrate; and

controlling one or more of the first thickness and the second thickness to maintain the average flexural strength of the glass substrate and the functional properties of the film.

38. The method of claim 37, further comprising disposing an additional film on the glass substrate, the additional film comprising a protective layer, an adhesive layer, a planarizing layer, an anti-splintering layer, an optical bonding layer, a display layer, a polarizing layer, or a light-absorbing layer.

39. The method of claim 37, further comprising strengthening the glass substrate.

40. An article comprising:

a glass substrate having opposing major surfaces and a first toughness;

a crack mitigating layer disposed on a first major surface; and

a film disposed on the crack mitigating layer,

wherein the crack mitigating layer comprises a low-adhesion interface having a second toughness less than about 0.5 times the first toughness of the glass substrate and prevents cracks originating in one of the film or the glass substrate from bridging to the other of the film or the glass substrate.

41. The article of claim 40, wherein the glass substrate is strengthened or strong and has an average strain-to-failure in the range from about 0.5% to about 2%.

42. The article of claim 41, wherein the glass substrate is chemically strengthened and has a surface compressive stress greater than about 500 MPa and a compressive depth-of-layer greater than about 15 μ

m.

43. An article comprising:

a glass substrate having opposing major surfaces, wherein the glass substrate has a first average strain-to-failure that is greater than about 0.5% and is optionally strengthened;

a crack mitigating layer disposed on a first major surface; and

a film disposed on the crack mitigating layer,

wherein the crack mitigating layer prevents cracks originating in one of the film or the glass substrate from bridging to the other of the film or the glass substrate.

44. The article of claim 43, wherein the crack mitigating layer has a second average strain-to-failure, and the film has a third average strain-to-failure, and

wherein the first average strain-to-failure and the second average strain-to-failure are greater than the third average strain-to-failure.

45. The article of claim 43, further comprising at least two functional properties selected from the functional properties of optical properties, electrical properties and mechanical properties, wherein the at least two functional properties are maintained or improved over an article comprising the glass substrate and the film but not the crack mitigating layer.

46. The article of claim 45, wherein the at least two functional properties comprise optical properties and electrical properties.

47. The article of claim 45, wherein the at least two functional properties comprise optical properties and mechanical properties.

48. The article of claim 45, wherein the at least two functional properties comprise electrical properties and mechanical properties.

49. The article of claim 43, further exhibiting a greater average flexural strength and lower average reflectance over a wavelength range from 450-650 nm than an article comprising the glass substrate and the film but not the crack mitigating layer.

50. The article of claim 43, wherein the film comprises more than one layer, wherein the more than one layer comprise one or more of optical interference layers, barrier layers, surface modifying layers, insulating layers, passivation layers, seeding layers, hermetic layers, and diffusion-blocking layers.

51. A touch-sensing device comprising the article of claim 43.

52. An information display device comprising the article of claim 43.

53. The article of claim 43, wherein the first average strain-to-failure is greater than an amount selected from 0.7%, 1.0%, 1.5% and 2%.

54. The article of claim 43, further exhibiting at least one of an average flexural strength that is greater than the average flexural strength of an article comprising the glass substrate and the film but without the crack mitigating layer or an average strain-to-failure that is greater than the average strain to failure of an article comprising the glass substrate and the film but without the crack mitigating layer.

55. The article of claim 43, further exhibiting at least one of an average flexural strength that is substantially the same as the average flexural strength of the glass substrate or an average strain-to-failure that is substantially the same as the average strain-to-failure as the glass substrate.

56. The article of claim 43, wherein the film comprises a single layer or a plurality of layers forming a first thickness, and wherein the crack mitigating layer comprises a second thickness that is less than or equal to about 10 times the first thickness.

57. The article of claim 56, wherein the second thickness is less than or equal to about 5 times the first thickness.

58. The article of claim 56, wherein the first thickness and the second thickness are each less than about 10 micrometers.

59. The article of claim 43, wherein the crack mitigating layer comprises a ductile material.

60. The article of claim 59, wherein the ductile material exhibits an elongation to break value of greater than 1%.

61. The article of claim 59, wherein the ductile material exhibits an elongation to break value of greater than 2%.

62. The article of claim 59, wherein the ductile material exhibit exhibits an elongation to break value of greater than 5%.