FLEXIBLE HARDCOAT COMPOSITIONS, ARTICLES, AND METHODS

• US 20090004478A1
• Filed: 06/11/2008
• Published: 01/01/2009
• Est. Priority Date: 06/29/2007
• Status: Abandoned Application

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: BAETZOLD, JOHN P., McMan, Steven J., Stradinger, John J., Pokorny, Richard J., Johnson, Stephen A., Severance, Richard L.
• Application Number:
  US12/137,074
• Publication Number:
  US 20090004478A1
• Time in Patent Office: Days
• US Class Current: 428/412
• CPC Class Codes: C08G 18/672 Esters of acrylic or alkyl acrylic acid having only one group containing active hydrogen
• CPC Class Codes: C09D 175/16 having terminal carbon-to-carbon unsaturated bonds
• CPC Class Codes: C09J 2433/001 in the barrier layer
• CPC Class Codes: C09J 2433/006 in the substrate
• CPC Class Codes: C09J 2475/001 in the barrier layer
• CPC Class Codes: C09J 2475/006 in the substrate
• CPC Class Codes: C09J 7/29 Laminated material metallised plastics C09J7/22
• CPC Class Codes: Y10T 428/31507 Of polycarbonate
• CPC Class Codes: Y10T 428/31576 Ester monomer type [polyvinylacetate, etc.]

Abstract

Flexible hardcoat compositions and protective films are described comprising the reaction product one or more urethane (meth)acrylate oligomers; at least one monomer comprising at least three (meth)acrylate groups; and optionally inorganic nanoparticles. The cured hardcoat composition is preferably sufficiently flexible such that a 5 micron film can be bent around a 2 mm mandrel without cracking.

Claims

1. A protective film comprising:

a cured hardcoat comprising the reaction product of a polymerizable composition comprising

one or more urethane (meth)acrylate oligomers;

at least one monomer comprising at least three (meth)acrylate groups; and

optionally inorganic nanoparticles;

wherein the cured hardcoat composition is sufficiently flexible such that a 5 micron film can be bent around a 2 mm mandrel without cracking.

2. The protective film of claim 1 wherein the urethane (meth)acrylate oligomer(s) are a di-(meth)acrylate oligomer(s).

3. The protective film of claim 1 wherein a homopolymer of the urethane (meth)acrylate oligomer(s) has an elongation of at least 20%.

4. The protective film of claim 3 wherein the homopolymer of the urethane (meth)acrylate oligomer(s) has a tensile strength of at least 1,000 psi.

5. The protective film of claim 1 wherein the cured hardcoat is sufficiently durable such that the hardcoat exhibits a change in haze of less than 10% after the oscillating sand abrasion testing.

6. The protective film of claim 1 wherein the polymerizable composition comprises less than 40 wt-% of crosslinkers comprising more than four (meth)acrylate groups.

7. The protective film of claim 1 wherein the polymerizable composition comprises less than 20 wt-% of crosslinkers comprising more than four (meth)acrylate groups.

8. The protective film of claim 1 wherein the polymerizable composition is substantially free of crosslinkers comprising more than four (meth)acrylate groups.

9. The protective film of claim 1 wherein the one or more urethane (meth)acrylates are aliphatic.

10. The protective film of claim 1 wherein the polymerizable composition comprises at least one fluorine-containing or silicone-containing component.

11. The protective film of claim 10 wherein the fluorine-containing or silicone-containing component is copolymerizable.

12. The protective film of claim 11 wherein the polymerizable composition comprises an HFPO-urethane additive.

13. The protective film of claim 1 wherein the hardcoat composition comprises 0 wt-% to 30 wt-% inorganic nanoparticles.

14. The protective film of claim 13 wherein the inorganic nanoparticles comprise silica.

15. The protective film of claim 1 wherein the cured hardcoat composition is disposed on a light transmissive polymeric film substrate.

16. The protective film of claim 15 wherein the light transmissive film substrate is thermoplastic.

17. The protective film of claim 16 wherein the film substrate is selected from the group consisting of polycarbonate, polyethylene terephthalate, polyethylene naphthalate, and cellulose acetate.

18. The protective film of claim 15 wherein the film substrate is a reflective multi-layer optical film.

19. The protective film of claim 15 wherein the substrate further comprise a metal or organometallic layer.

20. The protective film of claim 1 wherein the light transmissive substrate further comprises an adhesive on a surface opposing the cured hardcoat.

21. The protective film of claim 1 wherein the cured hardcoat composition is disposed on a release liner.

22. The protective film of claim 1 wherein the protective film in an antireflective film having a high refractive index layer disposed on the hardcoat and a low refractive index layer is disposed on the high refractive index layer.

23. An article having a curved surface wherein the article comprises the protective film of claim 1.

24. A method of making an article comprising:

lining a surface of a mold cavity with a protective film according to any of the preceding claims;

injecting a solidifiable resin composition into the mold cavity;

solidifying the resin composition; and

removing the solidified resin article comprising the protective film from the mold.

25. The method of claim 24 wherein the protective film comprises the cured hardcoat composition disposed on a light transmissive thermoplastic film substrate.

26. The method of claim 24 wherein at least a portion of the surface of the lined mold cavity has a curved surface.

27. The method of claim 24 wherein the solidifiable resin is a molten thermoplastic resin.

28. The method of claim 24 wherein the solidifiable resin is a polymerizable resin.

29. The method of claim 28 wherein the polymerizable resin in a urethane polymerizable resin.

30. A hardcoat coating composition comprising

one or more urethane di-(meth)acrylate oligomers;

at least one monomer comprising at least three (meth)acrylate groups; and

optionally inorganic nanoparticles;

wherein the composition comprises less than 40 wt-% of crosslinkers comprising more that four (meth)acrylate groups.

31. The hardcoat coating composition of claim 30 wherein the polymerizable composition comprises less than 20 wt-% of crosslinkers comprising more that four (meth)acrylate groups.

32. The hardcoat coating composition of claim 30 wherein the polymerizable composition is substantially free of crosslinkers comprising more that four (meth)acrylate groups.

33. The hardcoat coating composition of claim 30 wherein the urethane (meth)acrylate oligomer(s) are a di-(meth)acrylate oligomer(s).

34. The hardcoat coating composition of claim 30 wherein a homopolymer of the urethane (meth)acrylate oligomer(s) has an elongation of at least 20%.

35. The hardcoat coating composition of claim 30 wherein the homopolymer of the urethane (meth)acrylate oligomer(s) has a tensile strength of at least 1,000 psi.