Antiglare coating and articles

• US 20060046071A1
• Filed: 08/26/2004
• Published: 03/02/2006
• Est. Priority Date: 08/26/2004
• Status: Active Grant

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Bottari, Frank J., Cairns, Darran R., Richter, Paul J.
• Granted Patent: US 7,291,386 B2
• Time in Patent Office: Days
• US Class Current: 428/432
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: C03C 1/008 for the production of films or coatings
• CPC Class Codes: C03C 17/007 containing a dispersed phase, e.g. particles, fibres or flakes, in a continuous phase
• CPC Class Codes: C03C 17/009 Mixtures of organic and inorganic materials, e.g. ormosils and ormocers
• CPC Class Codes: C03C 17/3411 with at least two coatings of inorganic materials C03C17/36, C03C17/42 take precedence
• CPC Class Codes: C03C 2203/22 using colloidal silica sols
• CPC Class Codes: C03C 2203/26 using alkoxides
• CPC Class Codes: C03C 2203/27 the alkoxides containing other organic groups, e.g. alkyl groups
• CPC Class Codes: C03C 2217/45 Inorganic continuous phases
• CPC Class Codes: C03C 2217/475 Inorganic materials
• CPC Class Codes: C03C 2217/478 Silica
• CPC Class Codes: C03C 2217/732 made of a single layer
• CPC Class Codes: C03C 2217/78 Coatings specially designed to be durable, e.g. scratch-resistant
• CPC Class Codes: C03C 2218/111 by dipping, immersion
• CPC Class Codes: C03C 2218/113 by sol-gel processes
• CPC Class Codes: G02B 5/0226 having particles on the surface
• CPC Class Codes: G02B 5/0278 used in transmission
• CPC Class Codes: G02B 5/0294 adapted to provide an additional optical effect, e.g. anti-reflection or filter
• CPC Class Codes: Y10T 428/25 Web or sheet containing structurally defined element or component and including a second component containing structurally defined particles
• CPC Class Codes: Y10T 428/259 Silicic material

Abstract

The present invention relates to articles comprising an antiglare layer, coating compositions suitable for making antiglare layers, methods of making an antiglare article, and methods of making antiglare coating compositions. In some embodiments the article is a (e.g. illuminated) display article such as a touch screen. The antiglare layer comprises aggregate silica particle in a cured inorganic polymer matrix.

Claims

1. A touch screen comprising a glass substrate, an active element for detecting a touch on the touch screen, and an antiglare layer wherein the antiglare layer comprises aggregate silica particles in a cured inorganic polymer matrix wherein the aggregates form surface structures ranging in size from 0.1 micrometers to 2 micrometers.

2. The touch screen of claim 1 wherein the touch screen has a reflected haze of at least 150.

3. The touch screen of claim 1 wherein the touch screen has a reflectance of less than 10%.

4. The touch screen of claim 1 wherein the touch screen has a transmission of at least 80%.

5. The touch screen of claim 1 wherein the touch screen has a scratch resistance as determined by the Nanoscratch Test of at least 10 mN.

6. The touch screen of claim 1 wherein the touch screen has a Taber Abrasion Resistance test of at least 100 cycles.

7. The touch screen of claim 1 wherein the touch screen has a time to failure as determined by the Polishing Test of at least 2 hours for a 1 micrometer antiglare layer.

8. The touch screen of claim 1 wherein the silica particles have a mean particle size ranging from about 0.05 micrometers to about 0.15 micrometers.

9. The touch screen of claim 1 wherein the surface structures have a dimension of at least 0.20 micrometers.

10. The touch screen of claim 1 wherein the surface structures have a dimension of at least 0.30 micrometers.

11. The touch screen of claim 1 wherein the cured inorganic polymer matrix is derived from an organosilane.

12. The touch screen of claim 11 wherein the cured inorganic polymer matrix is derived from a silicon alkoxide.

13. The touch screen of claim 11 wherein the cured organosilane is derived from a sol-gel process.

14. The touch screen of claim 1 wherein the surface layer has a total surface area and the surface structures comprise at least 20% of the total surface area.

15. The touch screen of claim 1 wherein the surface layer has a total surface area and the surface structures comprise at least 30% of the total surface area.

16. The touch screen of claim 1 wherein the surface layer has a total surface area and the surface structures comprise at least 40% of the total surface area.

17. The touch screen of claim 1, further comprising a silicon oxide layer disposed between the transparent conductive layer and the antiglare layer.

18. The touch screen of claim 1, wherein the active element comprises a transparent conductive layer disposed between the glass substrate and the antiglare layer.

19. The touch screen of claim 18, wherein the transparent conductive layer comprises a transparent conductive oxide.

20. The touch screen of claim 1 further comprising a liquid crystal silane surface layer.

21. An article comprising an antiglare layer wherein the antiglare layer comprises aggregate silica particles in a cured inorganic polymer matrix wherein the aggregate silica particles form surface structures ranging in size from 0.2 micrometers to 2 micrometers.

22. The article of claim 21 wherein the article is a display panel.

23. The article of claim 21 wherein the article is selected from the group comprising computer monitors, television screens, optical filters, picture frames, windows, mirrors, solar collector cover plates, optical lenses, and windshields for vehicles.

24. A coating composition comprising an organosilane and flocculated silica particles ranging in size from 0.2 micrometers to 2 micrometers.

25. The coating composition of claim 24 wherein the silica particles are present in a concentration of less than 10 wt-%.

26. A method of making an antiglare article comprising:

providing a transparent substrate;

coating the substrate with the coating composition of claim 24;

and

heating the coating composition.

27. The method of claim 26 wherein the substrate is selected from glass, polycarbonate, polymethylmethacrylate, and cellulose acetate butyrate.

28. A method of making an antiglare coating composition comprising:

providing an inorganic polymer precursor and colloidal silica particles having a mean particle size ranging from 0.05 micrometers to 0.15 micrometers; and

forming an inorganic polymer solution concurrently with flocculating colloidal silica aggregates.

29. The method of claim 28 wherein the method comprises the addition of sodium acetate.