Haze-resistant transparent film stacks

• US 20040146721A1
• Filed: 01/15/2004
• Published: 07/29/2004
• Est. Priority Date: 12/02/1999
• Status: Abandoned Application

• Current Assignee: Annette Krisko, Klaus Hartig
• Original Assignee: Annette Krisko, Klaus Hartig
• Inventors: Hartig, Klaus, Krisko, Annette
• Application Number:
  US10/759,971
• Publication Number:
  US 20040146721A1
• Time in Patent Office: Days
• US Class Current: 428/432
• 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 17/3642 the multilayer coating containing a metal layer
• 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 17/3686 the multilayer coating being used for ovens
• CPC Class Codes: Y10T 428/24975 No layer or component greater than 5 mils thick
• CPC Class Codes: Y10T 428/265 1 mil or less

Abstract

The invention provides a haze-resistant temperable coating which desirably includes an inner dielectric layer, a first silver layer; an intermediate dielectric stack a second silver layer, and an outer dielectric layer. The intermediate dielectric stack may have alternating layers of a first dielectric and a second dielectric, with each of the alternating layers having an optical thickness of no more than about 450 A or a physical thickness of no more than about 250 A. In a preferred coating, the first dielectric has an index of refraction between about 90% and 110% of that of the second dielectric and the first and second dielectric have different microstructures to limit crystal growth therebetween during tempering.

Claims

1. A coating carried by a substrate having a surface, comprising, from the substrate surface outwardly:

a) an inner dielectric layer;

b) a first infrared reflective layer;

c) an intermediate dielectric stack comprising alternating layers of a first dielectric and a second dielectric, wherein the intermediate dielectric stack includes, moving outwardly, a first intermediate dielectric layer of said first dielectric, a second intermediate dielectric layer of said second dielectric, a third intermediate dielectric layer of said first dielectric, a fourth intermediate dielectric layer of said second dielectric, and a fifth intermediate dielectric layer of said first dielectric, wherein each of the first, third, and fifth intermediate dielectric layers has an optical thickness greater than the optical thickness of any of the second and fourth intermediate dielectric layers, each intermediate dielectric layer having a physical thickness of no more than about 250 A;

d) a second infrared reflective layer; and

e) an outer dielectric layer.

2. The coating of claim 1 wherein said first dielectric is an oxide or suboxide and said second dielectric is a nitride, such that the first, third, and fifth intermediate dielectric layers comprise an oxide or suboxide while the second and fourth intermediate dielectric layers comprise a nitride.

3. The coating of claim 1 wherein the first, third, and fifth intermediate dielectric layers comprise an oxide of the same metal, and wherein the second and fourth intermediate dielectric layers comprise a nitride of the same metal.

4. The coating of claim 1 wherein said second dielectric is silicon nitride.

5. The coating of claim 1 wherein said first dielectric comprises an oxide or suboxide of a metal comprising zinc, indium, tin, bismuth or an alloy of zinc, indium, tin or bismuth, and said second dielectric comprises a nitride of a metal that is different from said metal of said first dielectric.

6. The coating of claim 1 wherein said first dielectric comprises an oxide or suboxide of zinc and the second dielectric comprises silicon nitride.

7. The coating of claim 1 wherein said first dielectric is polycrystalline and said second dielectric is substantially amorphous.

8. The coating of claim 1 including a layer comprising niobium between the first infrared reflective layer and the intermediate dielectric stack, and a layer comprising niobium between second infrared reflective layer and the outer dielectric layer.

9. The coating of claim 1 wherein said second intermediate dielectric layers is contiguous to said first intermediate dielectric layer, said third intermediate dielectric layers is contiguous to said second intermediate layer, said fourth intermediate dielectric layer is contiguous to said third intermediate dielectric layer, and said fifth intermediate dielectric layer is contiguous to said fourth intermediate dielectric layer.

10. A coating carried by a substrate having a surface, comprising, from the substrate surface outwardly:

a) an inner dielectric layer;

b) a first infrared reflective layer;

c) an intermediate dielectric stack comprising alternating layers of a first dielectric and a second dielectric, wherein the intermediate dielectric stack includes, moving outwardly, a first intermediate dielectric layer of said first dielectric, a second intermediate dielectric layer of said second dielectric, a third intermediate dielectric layer of said first dielectric, a fourth intermediate dielectric layer of said second dielectric, and a fifth intermediate dielectric layer of said first dielectric, wherein each of the first, third, and fifth intermediate dielectric layers has an optical thickness greater than the optical thickness of any of the second and fourth intermediate dielectric layers, said first dielectric being an oxide or suboxide and said second dielectric being a nitride, each intermediate dielectric layer having a physical thickness of no more than about 250 A;

d) a second infrared reflective layer; and

e) an outer dielectric layer.

11. A method of forming a coated glass article, the method comprising:

a) providing a glass substrate;

b) depositing a coating on the glass substrate by;

i) depositing an inner dielectric layer;

ii) thereafter, depositing a first infrared reflective layer;

iii) thereafter, depositing an intermediate dielectric stack by depositing alternating layers of a first dielectric and a second dielectric, wherein the intermediate dielectric stack includes, moving outwardly, a first intermediate dielectric layer of said first dielectric, a second intermediate dielectric layer of said second dielectric, a third intermediate dielectric layer of said first dielectric, a fourth intermediate dielectric layer of said second dielectric, and a fifth intermediate dielectric layer of said first dielectric, wherein each of the first, third, and fifth intermediate dielectric layers has an optical thickness greater than the optical thickness of any of the second and fourth intermediate dielectric layers, each intermediate dielectric layer having a physical thickness of no more than about 250 A;

iv) thereafter, depositing a second infrared reflective layer; and

v) thereafter, depositing an outer dielectric layer.

12. The method of claim 11 wherein said first dielectric is an oxide or suboxide and said second dielectric is a nitride, such that the first, third, and fifth intermediate dielectric layers are each deposited as oxide or suboxide film while the second and fourth intermediate dielectric layers are each deposited as nitride film.

13. The method of claim 11 wherein the first, third, and fifth intermediate dielectric layers are all deposited as film comprising an oxide of the same metal, and wherein the second and fourth intermediate dielectric layers are both deposited as film comprising a nitride of the same metal.

14. The method of claim 11 wherein said second dielectric is silicon nitride, such that the second and fourth intermediate dielectric layers are both deposited as film comprising silicon nitride.

15. The method of claim 11 wherein said first dielectric comprises an oxide or suboxide of a metal comprising zinc, indium, tin, bismuth or an alloy of zinc, indium, tin or bismuth, and said second dielectric comprises a nitride of a metal different from said metal of said first dielectric.

16. The method of claim 11 wherein said first dielectric comprises an oxide or suboxide of zinc and the second dielectric comprises silicon nitride.

17. The method of claim 11 wherein said first dielectric is polycrystalline and said second dielectric is substantially amorphous.

18. The method of claim 11 including depositing a layer comprising niobium between the first infrared reflective layer and the intermediate dielectric stack, and depositing a layer comprising niobium between second infrared reflective layer and the outer dielectric layer.

19. The method of claim 11 wherein said second intermediate dielectric layers is deposited directly upon said first intermediate dielectric layer, said third intermediate dielectric layers is deposited directly upon said second intermediate layer, said fourth intermediate dielectric layer is deposited directly upon said third intermediate dielectric layer, and said fifth intermediate dielectric layer is deposited directly upon said fourth intermediate dielectric layer.

20. The method of claim 11 wherein said coating is deposited by sputtering.