COLOR CONVERSION LUMINESCENT SHEET AND FABRICATION METHOD FOR THE SAME

• US 20120156436A1
• Filed: 10/20/2011
• Published: 06/21/2012
• Est. Priority Date: 12/15/2010
• Status: Abandoned Application

• Current Assignee: Korea Advanced Institute of Science and Technology
• Original Assignee: Korea Advanced Institute of Science and Technology
• Inventors: KIM, Jai Kyeong, NA, Dae Seok
• Application Number:
  US13/277,577
• Publication Number:
  US 20120156436A1
• Time in Patent Office: Days
• US Class Current: 428/172
• CPC Class Codes: B32B 3/30 characterised by a layer formed with recesses or projections, e.g. hollows, grooves, protuberances, ribs apertured layer B32B3/266; layer with cavities or internal voids B32B3/26
• CPC Class Codes: C09K 11/565 with zinc cadmium
• CPC Class Codes: C09K 11/88 containing selenium, tellurium or unspecified chalcogen elements
• CPC Class Codes: G02B 1/105 Protective coatings
• CPC Class Codes: G02B 1/14 Protective coatings, e.g. hard coatings
• CPC Class Codes: G02B 5/223 containing organic substances, e.g. dyes, inks or pigments
• CPC Class Codes: G02B 6/005 provided by one optical element, or plurality thereof, placed on the light output side of the light guide
• CPC Class Codes: H01L 2933/0041 relating to wavelength conversion elements
• CPC Class Codes: H01L 33/505 characterised by the shape, e.g. plate or foil
• CPC Class Codes: H10K 50/858 comprising refractive means, e.g. lenses
• CPC Class Codes: H10K 59/38 comprising colour filters or colour changing media [CCM]
• CPC Class Codes: Y10T 428/24612 Composite web or sheet

Abstract

A color conversion luminescent sheet and a method of preparing the same, the color conversion luminescent sheet including: an optical sheet having a plurality of protrusions and depressions on its lower surface; a conductive layer disposed on the upper surface of the optical sheet; a color conversion luminescent layer deposited on the upper surface of the conductive layer and comprising a mixture of nanofibers and nanobeads having a binder resin and a color conversion luminescent material; and a protective layer on the upper surface of the color conversion luminescent layer, the protective layer having a stacked structure including an organic polymer protective layer and an inorganic thin protective layer.

Claims

1. A color conversion luminescent sheet comprising:

an optical sheet having a plurality of protrusions and depressions on its lower surface;

a conductive layer disposed on the upper surface of the optical sheet; and

a color conversion luminescent layer deposited on the upper surface of the conductive layer and comprising a mixture of nanofibers and nanobeads having a binder resin and a color conversion luminescent material.

2. The color conversion luminescent sheet of claim 1, wherein each one of the protrusions and depressions has a cross-sectional shape selected from among a triangle, a polygon, a semi-circular pillar, a semi-oval pillar, a cone, and a microlens.

3. The color conversion luminescent sheet of claim 2, wherein the microlens shape has a height of from about 2 μ

m to about 150 μ

m, and a radius of curvature of from about 2 μ

m to about 150 μ

m.

4. The color conversion luminescent sheet of claim 1, wherein the optical sheet is selected from the group consisting of polyethylene terephthalate (PET), polymethyl methacrylate (PMMA), polycarbonate PC), polyethylene naphthalate (PEN), polystyrene (PS), and polyethylene sulfone (PES).

5. The color conversion luminescent sheet of claim 1, wherein the optical sheet has a thickness of from about 100 μ

m to about 500 μ

m.

6. The color conversion luminescent sheet of claim 2, wherein the conductive layer comprises at least one conductive material selected from the group consisting of indium tin oxide (ITO), F-doped SnO₂ (FTO), antimony tin oxide (ATO), indium zinc oxide (IZO), carbon nanotubes, graphene, polypyrrole, polyaniline, and polythiophene.

7. The color conversion luminescent sheet of claim 1, wherein the color conversion luminescent material is selected from the group consisting of inorganic fluorescent materials, organic fluorescent materials, organic luminescent polymers, phosphorescent materials, quantum dots, and combinations thereof.

8. The color conversion luminescent sheet of claim 1, wherein the color conversion luminescent layer has a thickness of from about 0.5 nm to about 200 nm.

9. The color conversion luminescent sheet of claim 1, further comprising a protective layer on the upper surface of the color conversion luminescent layer, the protective layer having a stacked structure including an organic polymer protective layer and an inorganic thin protective layer.

10. The color conversion luminescent sheet of claim 2, wherein the organic polymer protective layer comprises a cured product of a photocurable polymer selected from the group consisting of epoxy resins, acrylic resins, polyimides, and polyethylene.

11. The color conversion luminescent sheet of claim 9, wherein the inorganic thin protective layer comprises at least two inorganic materials selected from the group consisting of aluminum oxide, silicon oxide, silicon nitride, silicon oxynitride, magnesium oxide, indium oxide, and magnesium fluoride.

12. The color conversion luminescent sheet of claim 9, wherein the organic polymer protective layer has a thickness of from about 0.1 μ

m to about 10 μ

m, and the inorganic polymer protective layer has a thickness of from about 10 nm to about 1 μ

m.

13. The color conversion luminescent sheet of claim 1, further comprising a protective layer between the optical sheet and the conductive layer.

23. A luminescent device comprising the color conversion luminescent sheet of claim 1.

14. A method of preparing a color conversion luminescent sheet, the method comprising:

forming a conductive layer on one surface of an optical sheet having a plurality of protrusions and depressions on the other surface;

forming a mixed layer of nanofibers and nanobeads by spinning a color conversion luminescent composition prepared by mixing a binder resin, a color conversion luminescent material, and a solvent onto the upper surface of the conductive layer; and

thermally pressing the mixed layer of nanofibers and nanobeads to form a color conversion luminescent layer.

15. The method of claim 14, wherein the color conversion luminescent composition comprises a color conversion luminescent material of about 0.01 part to about 20 parts by weight, and a solvent of about 200 parts to about 10,000 parts by weight, each based on 100 parts by weight of the binder resin.

16. The method of claim 14, wherein the solvent comprises a polar solvent and a nonpolar solvent, and a weight ratio of the polar solvent to the nonpolar solvent is from about 2:

98 to about 60;

40.

17. The method of claim 14, wherein the conductive layer has an area specific resistance of from about 10 ohm/sq to about 2,000 ohm/sq.

18. The method of claim 14, wherein the spinning is carried out using electro-spinning, melt-blown spinning, electro-blown spinning, flash spinning, or electrostatic melt-blown spinning.

19. The method of claim 14, wherein the nanofiber has a diameter of from about 10 nm to about 10,000 nm, and the nanobead has a diameter of from about 30 nm to about 10,000 nm.

20. The method of claim 14, wherein the thermal pressing is carried out at a temperature of from about 25°

C. to about 150°

C.

21. The method of claim 14, further comprising a protective layer on an upper surface of the color conversion luminescent layer.

22. The method of claim 14, further comprising forming a protective layer on the surface of the optical sheet opposite to the surface of said protrusions and depressions before forming the conductive layer.