Multilayer with radiation absorber and touch screen

• US 20030170492A1
• Filed: 02/15/2002
• Published: 09/11/2003
• Est. Priority Date: 02/15/2002
• Status: Active Grant

• Current Assignee: Eastman Kodak Company
• Original Assignee: Eastman Kodak Company
• Inventors: Cok, Ronald S., Anderson, Charles C., Feldman, Rodney D.
• Granted Patent: US 6,846,579 B2
• Time in Patent Office: Days
• US Class Current: 428/690
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/045 using resistive elements, e.g. a single continuous surface or two parallel surfaces put in contact
• CPC Class Codes: Y10S 428/917 Electroluminescent
• CPC Class Codes: Y10T 428/24942 including components having same physical characteristic in differing degree

Abstract

Disclosed is a transparent multilayer comprising (a) a first conductive layer containing an intrinsically conductive polymer and a film forming binder, (b) a second conductive layer, and (c) spacer elements separating the first and second conductive layers, the first conductive layer further comprising an actinic radiation absorbing compound. The film is useful as a component in a touch screen display.

Claims

1. A transparent multilayer comprising (a) a first conductive layer containing an intrinsically conductive polymer and a film forming binder, (b) a second conductive layer, and (c) spacer elements separating the first and second conductive layers, the first conductive layer further comprising an actinic radiation absorbing compound.

2. The multilayer of claim 1 wherein the radiation absorbing compound absorbs UV radiation having a wavelength less than 400 nm.

3. The multilayer of claim 1 wherein the radiation absorbing compound absorbs radiation across a spectrum from 400 to 700 nm.

4. The multilayer of claim 1 wherein the radiation absorbing compound selectively absorbs light in a portion of the spectrum from 400 to 700 nm.

5. The multilayer of claim 1 wherein the radiation absorbing compound comprises a hydroxybenzophenone, a hydroxybenzotriazole, or a hydroxyphenyltriazine compound.

6. The multilayer of claim 1 wherein the radiation absorbing compound comprises a visible dye.

7. The multilayer of claim 1 wherein the intrinsically conductive polymer comprises at least one member selected from the group consisting of a substituted or unsubstituted polythiophene, polyaniline, polypyrrole, and poly(p-phenylene vinylene) compound.

8. The multilayer of claim 7 wherein the intrinsically conductive polymer is a polythiophene compound.

9. The multilayer or claim 8 wherein the intrinsically conductive polymer is a polyethylenedioxythiophene compound.

10. The multilayer of claim 1 wherein the first conductive layer contains embedded spacers that protrude from the surface of the layer.

11. The multilayer of claim 10 wherein the spacers are microspheres.

12. The multilayer of claim 11 wherein the microspheres are not water-wettable.

13. The multilayer of claim 12 wherein the microspheres comprise a polymeric resin.

14. The multilayer of claim 13 wherein the polymeric resin contains a cross-linked repeating unit.

15. The multilayer of claim 13 wherein the polymeric resin contains a repeating unit selected from styrenic and acrylic groups.

16. The multilayer of claim 9 wherein the polyethylenedioxythiophene polymer is represented Formula I wherein R₁ and R₂ are independently hydrogen or an alkyl, alkylenyl or cycloalkyl group having 1 to 4 carbon atoms, or together form a substituted or unsubstituted group or a substituted or unsubstituted 1,2-cyclohexylene group.

17. The multilayer of claim 1 additionally comprising a polyanion compound selected from the anions of polymericpolycarboxylic acids and polymericpolysulfonic acids.

18. The multilayer of claim 1 additionally comprising a conductivity enhancing compound selected from polyhydroxy, polycarboxy, polyamide and polylactam compounds.

19. The multilayer of claim 1 wherein the film forming binder comprises gelatins, gelatin derivatives, maleic acid or maleic anhydride copolymers, cellulose derivatives (such as carboxymethyl cellulose, hydroxyethyl cellulose, cellulose acetate butyrate, diacetyl cellulose, and triacetyl cellulose), polyvinyl alcohol, and poly-N-vinylpyrrolidone, acrylates, methacrylates, acrylamides and methacrylamides, itaconic acid and its half-esters and diesters, styrenes, acrylonitrile and methacrylonitrile, vinyl acetates, vinyl ethers, vinyl and vinylidene halides, and olefins;

polyurethanes, polyesterionomers;

or polysiloxanes.

20. A touch screen, comprising;

a) a transparent substrate having a first conductive layer;

b) a flexible transparent cover sheet having a second conductive layer on the surface and located relative to the transparent substrate so that the first and second conductive layers face each other; and

c) spacer elements located between said conductive layers to prevent contact in the absence of external deformation;

wherein at least one of the first or second conductive layers comprises an intrinsically conductive polymer and a film forming binder, the layer further comprising a compound capable of absorbing actinic radiation.

21. A display device comprising an OLED and the screen of claim 20.

22. A display device of claim 21 wherein the transparent substrate is also a substrate of the OLED that emits light through the OLED substrate.

23. A display device of claim 21 wherein the transparent substrate is also a cover of the OLED that emits light through the transparent OLED cover.

27. The touch screen of claim 20, wherein the spacer elements are embedded in the conductive layer on the flexible transparent cover sheet.

28. The touch screen of claim 20, wherein the spacer elements are embedded in the conductive layer on the transparent substrate.

29. The touch screen of claim 20, wherein the conductive layer comprises an intrinsically conductive polymer is present on both the transparent substrate and the flexible transparent cover sheet.

24. A method of making a multilayer useful for a touch screen display of the type including a transparent substrate bearing a conductive layer, a flexible transparent cover sheet bearing a conductive layer, and spacer elements located between the substrate and the cover sheet, comprising the steps of:

a) providing a liquid coating medium containing an intrinsically conductive polymer, a film forming binder, and a compound capable of absorbing actinic radiation;

b) coating the liquid coating medium on the substrate or the cover sheet and drying the coating to form a first conductive layer,

c) providing a second conductive layer on the other of the substrate or cover sheet, and

d) joining the substrate and cover sheet with their conductive layers facing each other and with spacer elements there-between.

25. The method of claim 24, comprising the additional step of forming the coating on an OLED substrate so that the OLED emits light through the substrate.

26. The method of claim 24, comprising the additional step of forming the coating on the cover of an OLED so that the OLED emits light through the OLED cover.

30. The method of claim 24, wherein the spacer elements are included in the liquid coating medium and coated on the flexible transparent cover sheet.

31. The method of claim 24, wherein the spacer elements are included in the liquid coating medium and coated on the transparent substrate.

32. The method of claim 24, wherein the liquid coating medium is coated both the transparent substrate and the flexible transparent cover sheet.

33. The method of claim 24, wherein the first conductive layer is coated using spin coating.

34. The method of claim 24, wherein the first conductive layer is coated using web coating.

35. The method of claim 24, wherein the first conductive layer is coated using spray coating.

36. The method of claim 24, wherein the first conductive layer is coated using electro-coating.