HIGH REFRACTIVE INDEX MONOMERS FOR OPTICAL APPLICATIONS

• US 20080075959A1
• Filed: 10/03/2007
• Published: 03/27/2008
• Est. Priority Date: 12/30/2004
• Status: Abandoned Application

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Walker, Christopher, Mader, Roger, Kolb, Brant, Noyola, Joan, Goenner, Emily, Wang, Sharon
• Application Number:
  US11/866,521
• Publication Number:
  US 20080075959A1
• Time in Patent Office: Days
• US Class Current: 428/421
• CPC Class Codes: C07C 2603/18 Fluorenes; Hydrogenated fluorenes
• CPC Class Codes: C07C 69/653 Acrylic acid esters; Methacrylic acid esters; Haloacrylic acid esters; Halomethacrylic acid esters
• CPC Class Codes: G02B 1/10 Optical coatings produced by application to, or surface treatment of, optical elements G02B1/08 takes precedence
• CPC Class Codes: G02B 1/111 using layers comprising organic materials
• CPC Class Codes: G02B 1/14 Protective coatings, e.g. hard coatings
• CPC Class Codes: Y10T 428/256 Heavy metal or aluminum or compound thereof
• CPC Class Codes: Y10T 428/31504 Composite [nonstructural laminate]
• CPC Class Codes: Y10T 428/3154 Of fluorinated addition polymer from unsaturated monomers

Abstract

The present invention includes optical coatings containing ultraviolet curable monomers employing a bromine substituted fluorene structure. The fluorene backbone of the monomers of the present invention may also be functionalized with one or more polymerizable or reactive functionalities, and most readily at the 9 position. Compositions of the present invention include the reactive bromosubstituted fluorenes combined with inorganic nanoparticles, particularly nanoparticles with reactive surface modifiers exhibiting polymerizable functionality. Reactive high index nanoparticles such as surface modified zirconia are contemplated.

Claims

1. An optical coating comprising:

a monomer containing a substituted fluorene structure wherein said fluorene structure is a bromo-substituted fluorene; and

surface modified inorganic nanoparticles dispersed within said fluorene, wherein said optical coating has a refractive index of at least 1.58.

2. The coating of claim 1 wherein said bromo-substituted fluorene is selected from the group of monomers defined by the following formulas:

3. The coating of claim 2 wherein said bromo substituted fluorene monomer is selected from the group consisting of acrylic acid 3-[9-(3-acryloyloxy-propyl)-2,3,7-tribromo-9H-fluoren-9-yl]-propyl ester, acrylic acid 3-{9-[3-acyloyloxy-propoxy)-propyl]-2,3,7-tribromo-9H-fluoren-9-yl}-propyl ester, 3-[9-(3-acryloyloxy-propyl)-2,7-dibromo-9H-fluoren-9-yl]-propyl ester, and 2-[9-(2-acryloyloxy-ethyl)-2,7-dibromo-9H-fluoren-9-yl]-ethyl ester.

4. The coating of claim 1 wherein said bromo-substituted fluorene is functionalized with one or more polymerizable functionalities.

5. A display system comprising the coating of claim 1.

6. The display system of claim 5 further comprising a photoinitiator within said coating.

7. The coating of claim 1 wherein said surface modified inorganic nanoparticle comprises nanoparticles selected from the group consisting of titanium, antimony, silica, zirconia, mixed metal oxides, and mixtures thereof.

8. The coating of claim 1 wherein said nanoparticles are selected from the group consisting of surface modified crystalline zirconia, surface modified amorphous zirconia, and functionalized silica.

9. A nanocomposite coating comprising:

a polymer matrix formed from bromo-substituted fluorene; and

surface modified zirconia nanoparticles dispersed within said polymer matrix.

10. A coating comprising:

a polymeric substrate;

a hard coat layer fixed to the polymeric substrate;

a high refractive index optical layer fixed to the hard coat layer, said high refractive index optical layer comprising a bromine substituted fluorene structure; and

an optional low refractive index optical layer fixed to the high refractive index optical layer,

wherein said high refractive index optical layer has a refractive index of at least 1.6 and said optional low refractive index layer has a refractive index less than 1.5.

11. The coating of claim 10 wherein said fluorene structure is bromine substituted at one or more of the 2, 3, and 7 positions.

12. The coating of claim 10 wherein said high refractive index optical layer further comprises surface modified zirconia nanoparticles.

13. The coating of claim 10 wherein said high refractive index optical layer further comprises surface modified inorganic nanoparticles selected from the group consisting of nanoparticles formed from titanium, antimony, silica, zirconia, mixtures of metal oxides, and mixtures thereof.

14. The coating of claim 10 wherein said high refractive index optical layer further comprises a photoinitiator prior to curing.

15. The coating of claim 10 wherein said high refractive index optical layer comprises a polymer containing a bromine fluorene monomer substituted with a polymerizable functionality.

16. The coating of claim 15 wherein said polymerizable functionality is an acrylate group substituted at the 9-position of the fluorene monomer.

17. A display system comprising the coating of claim 10.