Polymerizable composition comprising low molecular weight organic component

• US 20060204676A1
• Filed: 03/11/2005
• Published: 09/14/2006
• Est. Priority Date: 03/11/2005
• Status: Abandoned Application

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Goenner, Emily S., Jones, Clinton L., Kolb, Brant U., Olson, David B.
• Application Number:
  US11/077,598
• Publication Number:
  US 20060204676A1
• Time in Patent Office: Days
• US Class Current: 428/1.100
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: C08L 33/08 Homopolymers or copolymers of acrylic acid esters
• CPC Class Codes: C08L 33/10 Homopolymers or copolymers of methacrylic acid esters
• CPC Class Codes: C09K 2323/00 Functional layers of liquid crystal optical display excluding electroactive liquid crystal layer characterised by chemical composition
• CPC Class Codes: C09K 2323/035 Ester polymer, e.g. polycarbonate, polyacrylate or polyester
• CPC Class Codes: G02B 1/04 made of organic materials, e.g. plastics G02B1/08 takes precedence
• CPC Class Codes: G02B 6/0053 Prismatic sheet or layer; Brightness enhancement element, sheet or layer
• CPC Class Codes: G02B 6/0065 Manufacturing aspects; Material aspects
• CPC Class Codes: G02F 1/133507 Films for enhancing the luminance
• CPC Class Codes: Y10S 977/84 Manufacture, treatment, or detection of nanostructure
• CPC Class Codes: Y10S 977/932 for electronic or optoelectronic application
• CPC Class Codes: Y10S 977/939 Electron emitter, e.g. spindt emitter tip coated with nanoparticles
• CPC Class Codes: Y10T 428/24479 including variation in thickness
• CPC Class Codes: Y10T 428/256 Heavy metal or aluminum or compound thereof
• CPC Class Codes: Y10T 428/257 Iron oxide or aluminum oxide
• CPC Class Codes: Y10T 428/258 Alkali metal or alkaline earth metal or compound thereof
• CPC Class Codes: Y10T 428/259 Silicic material
• CPC Class Codes: Y10T 428/2982 Particulate matter [e.g., sphere, flake, etc.]
• CPC Class Codes: Y10T 428/31855 Of addition polymer from unsaturated monomers

Abstract

Polymerizable compositions comprising particularly useful for brightness enhancing films.

Claims

1. A brightness enhancing film comprising:

a brightness enhancing polymerized structure comprising the reaction product of a substantially solvent free polymerizable composition comprising

an organic component comprising one or more ethylenically unsaturated monomers,

wherein the organic phase is free of oligomeric monomer having a number average molecular weight of greater than 450 g/mole; and

at least 10 wt-% inorganic nanoparticles.

2. The brightness enhancing film of claim 1 wherein the polymerizable composition has a refractive index of at least 1.47, a refractive index of at least 1.52, a refractive index of at least 1.55, or a refractive index of at least 1.60.

3. The brightness enhancing film of claim 1 wherein the organic component has a viscosity of less than 1000 cps at 180°

F., a viscosity of less than 1000 cps at 160°

F., a viscosity of less than 1000 cps at 140°

F., a viscosity of less than 1000 cps at 120°

F., a viscosity of less than 800 cps at 120°

F., or a viscosity of less than 600 cps at 120°

F.

6. The brightness enhancing film of claim 1 wherein the organic component comprises at least one monomer having a refractive index of at least 1.47.

7. The brightness enhancing film of claim 6 wherein the organic component comprises a monomer selected from the group consisting of phenoxy ethyl acrylate;

phenylthio ethyl acrylate;

2-naphthylthio ethyl acrylate;

1-naphthylthio ethyl acrylate;

2,4,6-tribromophenoxy ethyl acrylate;

2,4-dibromophenoxy ethyl acrylate;

2-bromophenoxy ethyl acrylate;

1-naphthyloxy ethyl acrylate;

2-naphthyloxy ethyl acrylate;

phenoxy 2-methylethyl acrylate;

phenoxyethoxy ethyl acrylate;

3-phenoxy-2-hydroxy propyl acrylate;

2-phenylphenoxy ethyl acrylate;

4-phenylphenoxy ethyl acrylate;

2,4-dibromo-6-sec-butylphenyl acrylate;

2,4-dibromo-6-isopropylphenyl acrylate;

benzyl acrylate;

phenyl acrylate;

2,4,6-tribromophenyl acrylate; and

mixtures thereof.

8. The brightness enhancing film of claim 1 wherein the organic component comprises at least one monomer having a refractive index of at least 1.50 in combination with a second monomer having a refractive index of less than 1.50.

9. The brightness enhancing film of claim 8 wherein the second monomer has a refractive index of less than 1.47.

10. The brightness enhancing film of claim 1 wherein at least one monomer of the organic component has at least two ethylenically unsaturated groups.

11. The brightness enhancing film of claim 10 where the monomer is selected from hexanediol diacrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, trimethylolpropane tri(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, trimethylolpropane ethoxylate tri(meth)acrylate, glyceryl tri(meth)acrylate, pentaerythritol propoxylate tri(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, and mixtures thereof.

12. The brightness enhancing film of claim 1, wherein the polymerized structure has a plurality of ridges extending along a first surface.

13. The brightness enhancing film of claim 12 wherein the ridges have rounded apexes having a radius ranging from 4 to 15 micrometers.

14. The brightness enhancing film of claim 1, wherein the inorganic nanoparticles have a primary particle size in a range selected from 1 nm to 100 nm, 5 nm to 75 nm, or 10 nm to 30 nm.

15. The brightness enhancing film according to claim 1, wherein the inorganic nanoparticles comprise 10 wt-% to 60 wt-% or 10 wt-% to 40 wt-% of the polymerized structure.

16. The brightness enhancing film according to claim 1, wherein the nanoparticles are selected from silica, zirconia, titania, antimony oxides, alumina, tin oxides, mixed metal oxides thereof, or mixtures thereof.

17. The brightness enhancing film according to claim 1, wherein the nanoparticles are surface modified such that the nanoparticles are polymerizable with the organic component.

18. The brightness enhancing film according to claim 1 wherein the base layer is a polarizing layer.

19. The brightness enhancing film according to claim 18 wherein the base layer is a reflective polarizing layer.

20. A device comprising:

(a) a lighting device having a light-emitting surface; and

(b) the brightness enhancing film of claim 1 placed substantially parallel to said light-emitting surface.

21. The device according to claim 20, wherein the lighting device is a back-lit display device or a liquid crystal display device.

22. The device according to claim 20, wherein the device is selected from a handheld device, a computer display and a television.

23. The brightness enhancing film of claim 1 wherein the film is a turning film and the refractive index of the polymerizable composition is at least 1.44.

24. The brightness enhancing film of claim 23 wherein the film has rounded apexes having a radius ranging from 0.5 to 10 micrometers.

25. An illumination device comprising:

(a) a lighting source having a lightguide having a light-emitting surface; and

(b) the turning film of claim 24 placed substantially parallel to said lightguide, said turning film having a first surface and a second surface and an array of prisms formed on the first surface, the turning film disposed with the first surface disposed in relation to the light-emitting surface such that light rays exiting the light-emmiting surface of the lightguide encounter the array of prisms and are reflected and refracted by the array of prisms such that the light rays exit the turning film via the second surface and substantially along a desired angular direction,

wherein the array of prisms includes a first plurality of prisms, each of the first plurality of prisms having a first prism configuration, and a second plurality of prisms each having a second prism configuration, different than the first prism configuration, the first prism configuration and the second prism configuration being such the light rays exiting the second surface correspond to a substantially uniform sampling of the light rays entering the lightguide.

4. The brightness enhancing film of 1 wherein the polymerizable composition comprises photoinitiator.

5. The brightness enhancing film of claim 4 where in the polymerizable composition is cured by means of ultraviolet radiation.

26. A brightness enhancing film comprising:

a brightness enhancing polymerized structure comprising the reaction product of a substantially solvent free polymerizable composition comprising

an organic component comprising one or more ethylenically unsaturated monomers,

wherein the organic phase is free of oligomeric monomer having a number average molecular weight of greater than 450 g/mole and the polymerizable composition comprises at least one ingredient that comprises at least two ethylenically unsaturated groups.

27. A microstructured article comprising the reaction product of a substantially solvent free polymerizable composition comprising an organic component comprising one or more ethylenically unsaturated monomers and optionally inorganic nanoparticles, wherein the organic component is free of oligomeric monomer having a number average molecular weight of greater than 450 g/mole and the polymerizable composition comprises at least one ingredient that comprises at least two (meth)acrylate groups.

28. The microstructured article of claim 27 wherein the article is retroreflective.

29. The microstructured article of claim 27 wherein the article is a flexible mold suitable for making barrier ribs fro a plasma display panel.