Polymerizable compositions comprising nanoparticles

• US 20050200278A1
• Filed: 03/11/2005
• Published: 09/15/2005
• Est. Priority Date: 09/12/2003
• 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., Brady, John T., Olson, David B.
• Granted Patent: US 7,282,272 B2
• Time in Patent Office: Days
• US Class Current: 313/582
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: C08F 2/44 Polymerisation in the presence of compounding ingredients, e.g. plasticisers, dyestuffs, fillers
• CPC Class Codes: C08F 222/1025 of aromatic dialcohols
• CPC Class Codes: C08F 222/103 of trialcohols, e.g. trimethylolpropane tri(meth)acrylate
• 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 2323/03 Viewing layer characterised by chemical composition
• CPC Class Codes: C09K 2323/031 Polarizer or dye
• CPC Class Codes: G02B 5/02 Diffusing elements; Afocal elements
• CPC Class Codes: G02B 5/045 Prism arrays
• CPC Class Codes: G02B 5/124 plural reflecting elements forming part of a unitary plate or sheet
• 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: Y10S 428/913 Material designed to be responsive to temperature, light, moisture
• CPC Class Codes: Y10S 977/773 Nanoparticle, i.e. structure having three dimensions of 100 nm or less
• CPC Class Codes: Y10S 977/778 within specified host or matrix material, e.g. nanocomposite films
• 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 428/24355 Continuous and nonuniform or irregular surface on layer or component [e.g., roofing, etc.]
• CPC Class Codes: Y10T 428/24372 : Particulate matter
• CPC Class Codes: Y10T 428/31504 : Composite [nonstructural laminate]
• CPC Class Codes: Y10T 428/31855 : Of addition polymer from unsaturated monomers

Abstract

Polymerizable compositions comprising nanopartilces particularly useful for brightness enhancing films.

Claims

1. A brightness enhancing film having a polymerized structure comprising the reaction product of

a) at least about 15 wt-% of one or more first monomers selected from the group consisting of:

i) a monomer comprising a major portion having the structure

wherein R1 is independently hydrogen or methyl,

R2 is independently hydrogen or bromine,

Q is independently O or S, and

Z is independently —

C(CH₃)₂—

, —

CH₂—

, —

C(O)—

, —

S—

, —

S(O)—

, or —

S(O)₂—

;

ii) a monomer comprising a major portion having the structure

wherein R1 is independently hydrogen or methyl,

R2 is independently hydrogen or bromine,

Q is independently O or S,

Z is independently —

C(CH₃)₂—

, —

CH₂—

, —

C(O)—

, —

S—

, —

S(O)—

, or —

S(O)₂, and

L is a linking group independently selected from linear or branched C₂-C₁₂ alkyl groups wherein the carbon chain is optionally substituted with one or more oxygen group and/or the carbon atoms are optionally substituted with one or more hydroxyl groups;

and mixtures of i and ii;

b) at least about 10 wt-% of inorganic nanoparticles;

c) optionally a crosslinking agent.

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

3. The brightness enhancing film of claim 1 wherein the amount of inorganic particles is less than about 60 wt-%.

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

5. The brightness enhancing film of claim 1 wherein the inorganic nanoparticles comprise silica, zirconia, titania, antimony oxides, alumina, tin oxides, mixed metal oxides therof, or mixtures thereof.

6. The brightness enhancing film of claim 1 wherein the primary particle ranges in size from 5 nm to 75 nm, 10 nm to 30 nm, or 5 nm to 20 nm.

7. The brightness enhancing film of claim 1 wherein the first monomer consists of the reaction product of Tetrabromobisphenol A diglycidyl ether and (meth)acrylic acid.

8. The brightness enhancing film of claim 1 wherein the crosslinking agent is a liquid at ambient temperature.

9. The brightness enhancing film of claim 1 wherein the crosslinking agent is multi functional urethane (meth)acrylate crosslinker.

10. The brightness enhancing film of claim 1 wherein the crosslinking agent is selected from the group consisting of hexanediol diacrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, trimethylolpropane tri(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, hexanediol diacrylate, and mixtures thereof.

11. The brightness enhancing film of claim 1 further comprising at least one monofuntional or difunctional ethylenically unsaturated diluent.

12. The brightness enhancing film of claim 10 wherein the diluent is a liquid at room temperature.

13. The brightness enhancing film of claim 11 wherein the diluent comprises phenoxyethyl(meth)acrylate, benzyl(meth)acrylate, N-vinyl pyrrolidone, and N-vinyl caprolactam.

14. The brightness enhancing film of claim 11 wherein the diluent comprises N-substituted or N,N-disubstituted (meth)acrylamides.

15. The brightness enhancing film of claim 1 wherein the polymerizable composition is free of methacrylate functional monomer.

16. The brightness enhancing film of claim 1 wherein the film is a turning film optionally comprising rounded apexes having a radius of 0.5 to 10 micrometers.

17. An article comprising the brightness enhancing film of claim 1 and a second optical film in contact with the brightness enhancing film.

18. The article of claim 17 wherein the second optical film is selected from the group comprising a turning film, a diffuser, an absorbing polarizer, a reflective polarizer, and a protective cover film.

19. The article of claim 18 wherein the second optical film comprises a prismatic structure.

25. The brightness enhancing film of claim 1 wherein the structure comprises a plurality of ridges having rounded apexes having a radius ranging from 4 to 15 micrometers.

20. A brightness enhancing film having a polymerized structure comprising the reaction product of a polymerizable composition comprising

a) at least about 15 wt-% of one or more (meth)acrylated aromatic epoxy oligomers;

b) at least about 10 wt-% inorganic nanoparticles; and

c) optionally a crosslinking agent.

21. A polymerizable resin composition comprising

a) at least about 15 wt-% of one or more first monomers selected from the group consisting of:

i) a monomer comprising a major portion having the structure

wherein R1 is independently hydrogen or methyl,

R2 is independently hydrogen or bromine,

Q is independently O or S, and

Z is independently —

C(CH₃)₂—

, —

CH₂—

, —

C(O)—

, —

S—

, —

S(O)—

, or —

S(O)₂—

;

ii) a monomer comprising a major portion having the structure

wherein R1 is independently hydrogen or methyl,

R2 is independently hydrogen or bromine,

Q is independently O or S,

Z is independently —

C(CH₃)₂—

, —

CH₂—

, —

C(O)—

, —

S—

, —

S(O)—

, or —

S(O)₂—

, and

L is a linking group independently selected from linear or branched C₂-C₁₂ alkyl groups wherein the carbon chain is optionally substituted with one or more oxygen group and/or the carbon atoms are optionally substituted with one or more hydroxyl groups;

and mixtures of i and ii;

b) at least about 10 wt-% of inorganic nanoparticles;

c) optionally a crosslinking agent; and

d) optionally a photoinitiator.

22. An optical article comprising the reaction product of claim 21.

23. The optical article of claim 22 wherein the material is a film optionally having a microstructured surface.

24. The optical article of claim 24 wherein the microstructured surface comprises cube corner structures or structures suitable for making barrier ribs for a plasma display panel.

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 component has a viscosity of less than 1000 cps at 180°

F.; and

at least 10 wt-% inorganic nanoparticles.

27. The brightness enhancing film of claim 26 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.

28. The brightness enhancing film of claim 26 wherein the organic component comprises at least one (meth)acrylated urethane oligomer, (meth)acrylated polyester oligomer, (meth)acrylated phenolic oligomer, (meth)acrylated acrylic oligomer, (meth)acrylated epoxy(meth)acrylate and mixture thereof.

29. The brightness enhancing film of claim 26 wherein the organic component comprises at least one oligomeric ethylenically unsaturated monomer having a number average molecular weight of at least 450 g/mole.

30. A brightness enhancing film comprising:

a brightness enhancing polymerized structure comprising the reaction product of a substantially solvent free polymerizable composition comprises an organic component comprising one or more ethylenically unsaturated monomers wherein the organic component has a refractive index of at least 1.54; and

at least 10 wt-% inorganic nanoparticles.

31. The brightness enhancing film of claim 30 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.