Air oxidizable scratch resistant protective layer for optical coatings

• US 20060134436A1
• Filed: 12/19/2005
• Published: 06/22/2006
• Est. Priority Date: 12/17/2004
• Status: Abandoned Application

• Current Assignee: AGC Flat Glass North America Incorporated (AGC, Inc.)
• Original Assignee: AFG Industries Incorporated (AGC, Inc.)
• Inventors: Maschwitz, Peter Alan
• Application Number:
  US11/303,992
• Publication Number:
  US 20060134436A1
• Time in Patent Office: Days
• US Class Current: 428/426
• CPC Class Codes: C03C 17/36 at least one coating being a metal
• CPC Class Codes: C03C 17/3618 Coatings of type glass/inorganic compound/other inorganic layers, at least one layer being metallic
• CPC Class Codes: C03C 17/3626 one layer at least containing a nitride, oxynitride, boronitride or carbonitride
• CPC Class Codes: C03C 17/3639 Multilayers containing at least two functional metal layers
• 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 17/3681 the multilayer coating being used in glazing, e.g. windows or windscreens
• CPC Class Codes: C03C 17/3689 one oxide layer being obtained by oxidation of a metallic layer
• CPC Class Codes: C03C 2217/78 Coatings specially designed to be durable, e.g. scratch-resistant
• CPC Class Codes: C23C 28/321 with at least one metal alloy layer
• CPC Class Codes: C23C 28/322 only coatings of metal elements only
• CPC Class Codes: C23C 28/34 including at least one inorganic non-metallic material layer, e.g. metal carbide, nitride, boride, silicide layer and their mixtures, enamels, phosphates and sulphates
• CPC Class Codes: C23C 28/345 with at least one oxide layer
• CPC Class Codes: C23C 28/3455 with a refractory ceramic layer, e.g. refractory metal oxide, ZrO2, rare earth oxides or a thermal barrier system comprising at least one refractory oxide layer
• CPC Class Codes: C23C 8/02 Pretreatment of the material to be coated C23C8/04 takes precedence
• CPC Class Codes: G02B 1/105 Protective coatings
• CPC Class Codes: G02B 1/14 Protective coatings, e.g. hard coatings
• CPC Class Codes: Y10T 428/265 1 mil or less

Abstract

The present invention provides a scratch protecting layer comprising a metal, metal alloy, metal compound or an intermetallic layer deposited on an air contacting surface. The scratch protecting layer is typically from 1 to 3 nanometers thick and not optically absorbing after oxidation occurs. This layer is initially deposited in a primarily unoxidized or un-nitrided state. Full oxidation of the metal, metal alloy, metal compound or intermetallic layer occurs within several days after exposure to air. The scratch protection layer can be 2 to 5 nanometers thick if the layer is exposed to a plasma, electrical discharge or ion beam comprising a reactive gas such as oxygen or nitrogen.

Claims

1. An article with improved scratch protection, comprising

a substrate,

an optical coating comprising one or more layers on the substrate, and

an outermost scratch protection layer comprising a protective metal, metal alloy, metal compound or intermetallic coating, wherein said outermost scratch protection layer is 1 to 3 nm thick.

2. The article according to claim 1, wherein said metal is fully oxidized.

3. The article according to claim 1, wherein the metal portion of said metal alloy or metal compound is selected from the group consisting of chromium, iron, titanium, zirconium, hafnium, niobium, tantalum, molybdenum, tungsten, iron, aluminum and silicon.

4. The article according to claim 3, wherein said metal portion is zirconium.

5. The article according to claim 1, wherein the metal is zirconium.

6. The article according to claim 1, wherein said substrate is a transparent substrate.

7. The article according to claim 6, wherein said transparent substrate is glass with optical coatings deposited on it.

8. The article according to claim 7, wherein said optical coatings comprise one or more layers of NiCrO_x, Ag, and SiAlN_x.

9. The article according to claim 8, wherein the metal is zirconium.

10. The article according to claim 1, wherein the outermost scratch protection layer does not change the spectral reflectance and/or transmission in the visible or infrared wavelengths of the article.

11. The article according to claim 1, wherein the outermost scratch protection layer is deposited onto a layer of SiAlOxNy.

12. An article with improved scratch protection, comprising

a substrate,

an optical coating comprising one or more layers on the substrate, and

an outermost scratch protection layer comprising a protective metal, wherein said outermost scratch protection layer is 2 to 5 nm thick.

13. A method for improving the scratch protection of optical coatings on an article, comprising

depositing an optical coating comprising one or more layers on an article,

depositing a 1-3 nm layer comprising an unoxidized metal, metal alloy, metal compound or intermetallic on said optical coating to provide a scratch protection layer, and

oxidizing said metal, metal alloy, metal compound or intermetallic layer.

14. The method according to claim 13, wherein the metal portion of said metal alloy or metal compound is selected from the group consisting of chromium, iron, titanium, zirconium, hafnium, niobium, tantalum, molybdenum, tungsten, iron, nickel, aluminum and silicon.

15. The method according to claim 14, wherein said metal portion is zirconium.

16. The method according to claim 13, wherein said substrate is a transparent article.

17. The method according to claim 13, wherein said substrate is glass.

18. The method according to claim 13, wherein said optical coating includes one or more layers of NiCrO_x, Ag, and SiAlN_x.

19. The method according to claim 13, wherein said metal, metal alloy, metal compound or intermetallic layer is oxidized by exposure to air.

20. The method according to claim 13, wherein said scratch protection layer is deposited onto a layer of SiAlOxNy.

21. The method according to claim 13, wherein said metal has an oxide heat of formation less than −

150 kCal/mole and a melting point of greater than 1600 degrees centigrade.

22. The method according to claim 21, wherein said metal has a heat of formation less than −

200 kCal/mole and a melting point greater than 1600 degrees centigrade.

23. The method according to claim 13, wherein said metal oxidizes in ambient air to a substantially transparent state within 250 hours after the metal is deposited.

24. The method according to claim 23, wherein said metal oxidizes to a substantially transparent state within 25 hours after the metal is deposited.

25. The method according to claim 24, wherein said metal oxidizes to a substantially transparent state within 1 hour after the metal is deposited.

26. A method for improving scratch protection of an article with an optical coating, comprising

depositing an optical coating comprising one or more layers on an article,

depositing a 2-5 nm layer comprising an unoxidized metal, metal alloy, metal compound or intermetallic layer on said optical coating to provide a scratch protection layer, and

oxidizing said metal, metal alloy, metal compound or intermetallic layer by exposure to a plasma, electrical discharge or ion beam comprising a reactive gas.

27. The method according to claim 26, wherein said reactive gas is oxygen or nitrogen.