Polymerizable composition comprising low molecular weight organic component

• US 8,034,421 B2
• Filed: 09/10/2010
• Issued: 10/11/2011
• Est. Priority Date: 03/11/2005
• Status: Active Grant

• 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.
• Primary Examiner(s): WU, SHEAN CHIU
• Application Number:
  US12/879,057
• Publication Number:
  US 20100331442A1
• Time in Patent Office: 396 Days
• Field of Search: 428/1.1, 428/1.33, 428/148, 428328-331, 349113-115, 977/840, 977/939, 523/202
• US Class Current: 428/1.1
• 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 having a number average molecular weight up to 450 g/mole, at least one of the monomers comprising at least two ethylenically unsaturated groups and surface modified inorganic nanoparticles, wherein the organic component is free of oligomeric ethylenically unsaturated monomer having a number average molecular weight of greater than 450 g/mole.

2. The brightness enhancing film according to claim 1, wherein the inorganic nanoparticles comprise 40 wt-% to 70 wt-% of the polymerized structure.

3. 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.

4. The brightness enhancing film of claim 1 wherein the surface modified inorganic nanoparticles comprise zirconia.

5. The brightness enhancing film of claim 4 wherein the surface modified zirconia nanoparticles comprise a carboxylic acid surface treatment.

6. The brightness enhancing film of claim 1 wherein the organic component has a refractive index of at least 1.50.

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 a monomer having a refractive index of less than 1.50.

9. The brightness enhancing film of claim 8 where the monomer that comprises at least two ethylenically unsaturated groups 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.

10. The brightness enhancing film of claim 1 wherein the polymerizable composition has a refractive index of at least 1.58.

11. The brightness enhancing film of claim 1 wherein the polymerizable composition has a refractive index of at least 1.60.

12. The brightness enhancing film according to claim 1, wherein the nanoparticles are polymerizable with the organic component.

13. The brightness enhancing film according to claim 1 wherein the polymerized structure is in contact with a base layer that is a polarizing layer.

14. The brightness enhancing film according to claim 13 wherein the base layer is a reflective polarizing layer.

15. The brightness enhancing film of claim 1 wherein the organic component has a viscosity of less than 1000 cps at 160°

F.

16. The brightness enhancing film of claim 1 wherein the organic component has a viscosity of less than 1000 cps at 140°

F.

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

18. 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 having a number average molecular weight up to 450 g/mole, at least one of the monomers comprising at least two ethylenically unsaturated groups and surface modified inorganic nanoparticles, wherein the organic component is free of oligomeric ethylenically unsaturated monomer having a number average molecular weight of greater than 450 g/mole.

19. The microstructured article of claim 18 wherein the article is retroreflective.

20. The microstructured article of claim 18 wherein the article is a flexible mold suitable for making barrier ribs for a plasma display panel.