Hydrophobic coating including DLC on substrate

• US 20020009593A1
• Filed: 08/13/2001
• Published: 01/24/2002
• Est. Priority Date: 05/03/1999
• Status: Active Grant

• Current Assignee: Guardian Glass LLC (KOCH Industries Incorporated)
• Original Assignee: Guardian Industries Corporation (KOCH Industries Incorporated)
• Inventors: Veerasamy, Vijayen S.
• Granted Patent: US 6,395,333 B2
• Time in Patent Office: Days
• US Class Current: 428/408
• CPC Class Codes: B05D 5/083 involving the use of fluoropolymers
• CPC Class Codes: B08B 17/06 by giving articles subject to fouling a special shape or arrangement
• CPC Class Codes: B08B 17/065 the surface having a microscopic surface pattern to achieve the same effect as a lotus flower
• CPC Class Codes: B32B 17/10018 comprising only one glass sheet
• CPC Class Codes: B32B 17/1033 Laminated safety glass or glazing containing temporary protective coatings or layers
• CPC Class Codes: B32B 17/10577 Surface roughness
• CPC Class Codes: B60S 1/54 using gas, e.g. hot air
• CPC Class Codes: B60S 1/58 for rear windows
• CPC Class Codes: B62D 35/007 Rear spoilers B62D35/001 takes precedence
• CPC Class Codes: C03C 17/22 with other inorganic material C03C17/34, C03C17/44 take precedence
• CPC Class Codes: C03C 17/3441 comprising carbon, a carbide or oxycarbide
• CPC Class Codes: C03C 17/36 at least one coating being a metal
• CPC Class Codes: C03C 17/3634 one layer at least containing carbon, a carbide or oxycarbide
• CPC Class Codes: C03C 17/3644 the metal being silver
• CPC Class Codes: C03C 17/3652 the coating stack containing at least one sacrificial layer to protect the metal from oxidation
• CPC Class Codes: C03C 17/366 Low-emissivity or solar control coatings
• CPC Class Codes: C03C 2217/282 Carbides, silicides
• CPC Class Codes: C03C 2217/76 Hydrophobic and oleophobic coatings
• CPC Class Codes: C03C 2217/78 Coatings specially designed to be durable, e.g. scratch-resistant
• CPC Class Codes: C03C 2218/151 by vacuum evaporation
• CPC Class Codes: C03C 2218/31 : Pre-treatment
• CPC Class Codes: C03C 23/0075 : Cleaning of glass specially adapted to plate glass B08B11/00
• CPC Class Codes: C03C 3/076 : with 40% to 90% silica, by weight C03C3/045 takes precedence
• CPC Class Codes: Y02T 10/82 : Elements for improving aerodynamics
• CPC Class Codes: Y10T 428/24942 : including components having same physical characteristic in differing degree
• CPC Class Codes: Y10T 428/265 : 1 mil or less
• CPC Class Codes: Y10T 428/30 : Self-sustaining carbon mass or layer with impregnant or other layer

Abstract

A substrate is coated with a hydrophobic coating that includes highly tetrahedral amorphous carbon that is a form of diamond-like carbon (DLC). In certain embodiments, the coating is deposited on the substrate in a manner to increase its hydrophobicity (e.g. so that the coating has an initial contact angle θ of at least about 100 degrees; and/or a surface energy of no more than about 20.2 mN/m). In certain embodiments, the coating is deposited in a manner such that it has an average hardness of at least about 10 GPa, more preferably from about 20-80 GPa.

Claims

1. A coated glass article comprising:

a glass substrate comprising, on a weight basis;

SiO₂ from about 60-80%,

Na₂O from about 10-20%,

CaO from about 0-16%,

K₂O from about 0-10%,

MgO from about 0-10%,

Al₂O₃ from about 0-5%;

a hydrophobic coating including diamond-like carbon (DLC) and sp³ carbon-carbon bonds provided on said glass substrate; and

wherein said hydrophobic coating has an initial contact angle θ

with a sessile drop of water thereon of at least about 100 degrees, and an average hardness of at least about 10 GPa.

2. The coated glass article of claim 1, wherein said initial contact angle is at least about 110 degrees.

3. The coated glass article of claim 2, wherein said initial contact angle is at least about 115 degrees.

4. The coated glass article of claim 2, wherein said initial contact angle is at least about 125 degrees.

5. The coated glass article of claim 1, wherein said coating has a surface energy Y_C of less than or equal to about 20.2 mN/m.

6. The coated glass article of claim 1, wherein said coating has a surface energy Y_C of less than or equal to about 19.5 mN/m.

7. The coated glass article of claim 1, wherein said coating has a surface energy Y_C of less than or equal to about 18.0 mN/m, and wherein the refractive index “

n”

of said coating is from about 1.5 to 1.7.

8. The coated glass article of claim 1, wherein said coating is in direct contact with said glass substrate.

9. The coated glass article of claim 1, further comprising a DLC-inclusive layer disposed between said coating and said glass substrate.

10. The coated glass article of claim 1, further comprising a low-E layer disposed between said coating and said glass substrate.

11. The coated glass article of claim 1, wherein said glass substrate is a soda lime silica glass substrate including from about 66-75% SiO₂, from about 10-20% Na₂O, from about 5-15% CaO, from about 0-5% MgO, from about 0-5% Al₂O₃, and from about 0-5% K₂O.

12. The coated glass article of claim 1, wherein said hydrophobic coating has an average hardness of at least about 20 GPa.

13. The coated glass article of claim 12, wherein said hydrophobic coating has an average hardness of from about 20-80 GPa.

14. The coated glass of claim 1, wherein said hydrophobic coating has a thickness of from about 100 -500 Å

.

15. The coated glass article of claim 1, wherein the coated glass article comprises the following characteristics:

16. The coated glass article of claim 1, wherein said hydrophobic coating includes sp³ carbon-carbon bonds subimplanted in a surface of said glass substrate so as to strongly bond said coating to said glass substrate.

17. The coated glass article of claim 1, wherein at least about 50% of carbon-carbon bonds in said hydrophobic coating are highly tetrahedral sp³ carbon-carbon bonds.

18. A coated article comprising:

a substrate;

a coating including diamond-like carbon (DLC) provided on said substrate, said coating including sp³ carbon-carbon bonds; and

wherein said coating has an initial contact angle θ

with a drop of water of at least about 100 degrees, and an average hardness of at least about 10 GPa.

19. The coated article of claim 18, wherein said initial contact angle is at least about 110 degrees, and wherein said substrate is substantially transparent to visible light.

20. The coated article of claim 18, wherein said substrate is one of glass and plastic.

21. A coated glass article comprising:

a glass substrate; and

a hydrophobic coating including diamond-like carbon (DLC) provided on said glass substrate, wherein said hydrophobic coating has an initial contact angle θ

with a drop of water of at least about 110 degrees, and an average hardness of at least about 10 GPa.

22. The coated glass article of claim 21, wherein said initial contact angle is at least about 115 degrees.

23. The coated glass article of claim 22, wherein said initial contact angle is at least about 125 degrees.

24. The coated glass article of claim 21, wherein said coating has a surface energy Y_C of less than or equal to about 20.2 mN/m.

25. The coated glass article of claim 24, wherein said coating has a surface energy Y_C of less than or equal to about 18.0 mN/m.

26. The coated glass article of claim 21, wherein said hydrophobic coating is one of:

(i) in direct contact with said glass substrate, and (ii) on said glass substrate in a manner such that at least one low-E layer is disposed between said substrate and said hydrophobic coating.

27. The coated glass article of claim 21, wherein said hydrophobic coating has an average hardness of from about 20-80 GPa.

28. The coated glass article of claim 27, wherein the coated glass article comprises the following characteristics:

29. The coated glass article of claim 21, wherein at least about 50% of carbon-carbon bonds in said hydrophobic coating are highly tetrahedral sp³ carbon-carbon bonds.

30. The coated glass article of claim 21, wherein the outermost 10Å

layer portion of coating 3 includes in atomic percentage;

from about 5-60% carbon (C), from about 0-40% oxygen (O) , from about 0-40% silicon (Si) , from about 10-95% hydrogen (H), and from about 0-10% fluorine (F).

31. The coated glass article of claim 21, wherein at least one 10Å

thick layer portion of the coating includes in atomic percentage;

from about 15-80% carbon (C), from about 5-45% oxygen (O), from about 5-45% silicon (Si), from about 0-30% hydrogen (H), and from about 0-10% fluorine (F).

32. The coated glass article of claim 21, wherein a ratio of carbon (C) to silicon (Si) in said coating is from about 1:

1 to 4;

1.

33. The coated glass article of claim 21, wherein the outermost 5Å

layer portion of said coating includes in atomic percentage at least about 25% H.

34. A coated glass article comprising:

a glass substrate; and

a coating including diamond-like carbon (DLC) provided on said glass substrate, wherein the outermost 5Å

of said coating includes in atomic percentage at least about 50% H.

35. The coated glass article of claim 34, wherein said coating has an initial contact angle θ

of at least about 110 degrees, and an average hardness of at least about 10 GPa.

36. The coated glass article of claim 34, wherein said coating has a surface energy Y_C of less than or equal to about 18.0 mN/m.

38. The method of claim 36, further comprising depositing the ta-C inclusive coating in a manner such that the ta-C inclusive coating has an initial contact angle θ

of at least about 115 degrees.

37. A method of making a coated article, the method comprising the steps of:

providing a substrate; and

depositing a highly tetrahedral amorphous carbon (ta-C) inclusive coating having more sp³ carbon-carbon bonds than sp² carbon-carbon bonds on the substrate in a manner such that the ta-C inclusive coating has an initial contact angle θ

of at least about 100 degrees.

39. The method of claim 37, further comprising plasma treating an outmost surface of the coating in order to provide at least H atoms in the coating proximate the outermost surface thereof, so as to reduce surface energy of the coating.

40. The method of claim 37, wherein said depositing step is carried out using at least plasma ion beam deposition.

41. The method of claim 40, wherein said depositing step includes using at least one of H₂ and acetylene feedstock gas.

42. The method of claim 40, wherein said depositing step includes varying ion energy within a range of from about 100 to 800 eV during said depositing so that the coating has different layer portions having different densities.

43. An automotive window comprising:

a substrate transparent to at least about 70% of visible light rays;

a highly tetrahedral amorphous carbon inclusive coating provided on said substrate, wherein said coating has a thickness of from about 50 to 1,000 Å and

a substantial number of sp³ carbon-carbon bonds;

wherein the automotive window comprises the following optical characteristics;

visible transmittance;

>

70%UV transmittance;

<

38%IR transmittance;

 

<

35%;

wherein said coating has an initial contact angle of at least about 100 degrees.

44. The automotive window of claim 43, wherein said substrate includes one of soda lime silica glass, borosilicate glass, and substantially transparent plastic, and wherein said coating has an average density of at least about 2.4 gm/cm³.

45. A coated glass article comprising:

a glass substrate;

at least one hydrophobic coating including diamond-like carbon (DLC) provided on said substrate; and

wherein at least one 10Å

thick layer portion of said hydrophobic coating includes, in atomic percentage, from about 15-80% carbon (C), from about 5-45% oxygen (O), from about 5-45% silicon (Si), from about 0-30% hydrogen (H), and from about 0-10% fluorine (F).

46. The coated glass article of claim 45, wherein a ratio of carbon (C) to silicon (Si) in at least one portion of said coating is approximately 1:

1.

47. A coated article comprising:

a glass substrate;

a coating including diamond-like carbon (DLC) provided on said glass substrate, said coating including sp³ carbon-carbon bonds; and

wherein said coating is doped so as to have an index of refraction “

n”

of no greater than about 1.75.

48. The coated article of claim 47, wherein said coating includes C, Si, and F atoms, and wherein an atomic ratio of C to Si in said coating may be from about 1:

1 to 4;

1.

49. A method of cleaning a glass substrate comprising the steps of:

providing a linear ion beam source;

directing an ion beam from the source toward the glass substrate in a manner so that impurities on a surface of the glass substrate are removed by the ion beam; and

said directing step being performed in a manner so as to create free radicals on the surface of the substrate.