Composition and method for a coating providing anti-reflective and anti-static properties

• US 6,638,630 B2
• Filed: 11/21/2001
• Issued: 10/28/2003
• Est. Priority Date: 09/13/1999
• Status: Expired due to Term

• Current Assignee: Chemat Technology, Inc.
• Original Assignee: Chemat Technology, Inc.
• Inventors: Park, Sung-Soon, Zheng, Haixing
• Primary Examiner(s): NAKARANI, DHIRAJLAL S
• Application Number:
  US09/991,765
• Publication Number:
  US 20020119325A1
• Time in Patent Office: 706 Days
• Field of Search: 106/287.16, 106/287.17, 106/287.19, 252/519.3, 252/520.1, 252/520.2, 252/521.6, 359/581, 359/585, 359/586, 427/419.1, 427/419.2, 427/419.3, 427/425, 427/427, 428/447, 428/697, 428/699, 428/701, 428/702, 428/704
• US Class Current: 428/447
• CPC Class Codes: C03C 17/3417 all coatings being oxide coatings
• CPC Class Codes: G02B 1/111 using layers comprising organic materials
• CPC Class Codes: Y10T 428/31612 As silicone, silane or siloxane
• CPC Class Codes: Y10T 428/31663 As siloxane, silicone or silane
• CPC Class Codes: Y10T 428/31667 Next to addition polymer from unsaturated monomers, or aldehyde or ketone condensation product

Abstract

Coating solutions having anti-reflective and anti-static properties, a coating derived therefrom, a substrate coated with the coating and methods for their preparation. A coating includes a sol-gel alkoxide polymeric material and a conductive colloidal metal compound material.

Claims

1. An apparatus comprising:

a substrate;

a first crystalline metal compound layer overlying the substrate comprising crystalline particles having a particle size less than one micron, the first layer having a first reflective index; and

a second layer overlying the substrate and having a second reflective index different than the first reflective index.

2. The apparatus of claim 1, wherein the second layer is derived from an alkoxide of the general formula:

3. The apparatus of claim 1, wherein the substrate comprises plastic.

4. The apparatus of claim 1, wherein the first layer overlies a surface of the substrate and the second layer overlies the first layer.

5. The apparatus of claim 4, wherein the thickness of the second layer is selected to destructively interfere with light reflected by the first layer.

6. The apparatus of claim 4, further comprising a hard coat layer overlying the surface of the substrate between the substrate and the first layer.

7. The apparatus of claim 1, wherein the first reflective index is greater than the second reflective index.

8. The apparatus of claim 1, wherein the metal compound of the first layer is selected from the group consisting of a metal oxide, a metal nitride, a metal carbide, and a metal fluoride.

9. A method comprising:

forming a first layer of a crystalline metal compound having a first reflective index on a surface of a substrate; and

forming a second layer having a second reflective index different than the first reflective index on the substrate.

10. The method of claim 9, wherein the second layer is derived from an alkoxide of the general formula:

11. The method of claim 10, wherein the second layer is applied over the first layer and after the application of the first layer and the second layer, the method further comprises exposing the substrate to a temperature of 50 to 100°

C.

12. The method of claim 10, wherein the second layer is applied over the first layer.

13. The method of claim 12, wherein the metal compound of the first layer is selected from the group consisting of indium tin oxide, indium oxide, tin oxide, antimony tin oxide, and titanium oxide.

14. The method of claim 12, further comprising controlling the pH of the colloid solution in the range of 2 to 8.

15. The method of claim 12, wherein the dispersing agent comprises an amide.

16. The method of claim 10, wherein forming the second layer further comprises:

subjecting the alkoxide to hydrolyzation and condensation in a reaction system containing a catalyst in an alcohol solution;

aging the system to form a sol-gel reaction product;

diluting the reaction product; and

forming the reaction product on the surface of the substrate.

17. The method of claim 9, wherein forming the first layer further comprises:

dispersing metal compound powders having a particle size of less than one micron with a dispersing agent into a colloid solution; and

forming the colloid solution layer on the surface of the substrate.

18. The method of claim 9, wherein the first layer and the second layer are introduced by a spinning process.

19. A method for preparing a coating solution comprising:

dispersing crystalline metal compound powders having a particle size less than one micron with a dispersing agent into a colloid; and

diluting the colloid.

20. The method of claim 19, wherein the metal compound is selected from the group consisting of a metal oxide, a metal nitride, a metal carbide, and a metal fluoride.