INTERFERENCE FILMS HAVING ACRYLAMIDE LAYER AND METHOD OF MAKING SAME

• US 20080160185A1
• Filed: 09/19/2007
• Published: 07/03/2008
• Est. Priority Date: 12/28/2006
• Status: Active Grant

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Devoe, Robert J., Everaerts, Albert I., Dunn, Douglas S., Moore, George G.I., Lyons, Christopher S., Maki, Stephen P., Roehrig, Mark A., Wright, Robin E., Endle, James P., Jonza, James M., Benson, Olester
• Granted Patent: US 8,120,854 B2
• Time in Patent Office: Days
• US Class Current: 427/162
• CPC Class Codes: G02B 5/286 having four or fewer layers, e.g. for achieving a colour effect
• CPC Class Codes: Y10T 428/31692 Next to addition polymer from unsaturated monomers

Abstract

A method for forming a color shifting film on a support, the film comprising a reflective stack disposed adjacent to the support and an image is disclosed. The reflective stack comprises an at least partially transparent spacer layer comprising a substituted acrylamide polymer disposed between a partially reflective first layer and a reflective second layer. The acrylamide layer has a thickness sufficient to produce an interference color.

Claims

1. A color shifting film comprising:

a support;

a reflective stack disposed adjacent to the support;

wherein the reflective stack comprises an at least partially transparent spacer layer comprising a substituted acrylamide polymer disposed between a partially reflective first layer and a reflective second layer; and

an image;

wherein the acrylamide layer has a thickness sufficient to produce an interference color.

2. The film of claim 1 wherein the partially reflective first layer is in contact with the support.

3. The film of claim 1 wherein the reflective second layer is in contact with the support.

4. The film of claim 1 wherein the reflective second layer is fully reflective.

5. The film of claim 1 wherein both reflective layers are partially reflective.

6. The film of claim 1 wherein the second reflective layer comprises layers of materials having differing refractive indices.

7. The film of claim 1 wherein the substituted acrylamide comprises N,N-dimethylacrylamide, N,N-diethylacrylamide, N,N-dipropylacrylamide, N,N-dibutylacrylamide, N-ethyl-N-methylacrylamide, N-(isobutoxymethyl)-acrylamide, N-(butoxymethyl)acrylamide, N-(allyloxymethyl)acrylamide, N-(isopropoxymethyl)acrylamide, N-propoxymethyl-acrylamide, N-ethoxymethyl-acrylamide, N-(methoxymethyl)acrylamide, N-propylacrylamide, N-isopropylacrylamide, N-butylacrylamide, N-isobutylacrylamide, N-decylacryl-amide (N-[3-(N,N-dimethylamino)propyl]acrylamide), (N-[3-(N,N-diethyl-amino)propyl]acrylamide), (N-[3-(N-ethyl-N-methylamino)butyl]acrylamide), N-{2,3,3,3-tetrafluoro-2-[1,1,2,3,3,3-hexafluoro-2-(1,1,2,2,3,3,3-heptafluoro-propoxy)-propoxy]-propyl}-acrylamide, 1-morpholin-4-yl-propenone, 1-piperidin-1-yl-propenone, 1-pyrrolidin-1-yl-propenone or a mixture thereof.

8. The film of claim 7 wherein the substituted acrylamide comprises, 1-morpholin-4-yl-propenone, 1-piperidin-1-yl-propenone, 1-pyrrolidin-1-yl-propenone or a mixture thereof.

9. The film of claim 8 wherein the substituted acrylamide comprises 1-morpholin-4-yl-propenone.

10. The film of claim 1 wherein the film comprises an optical element.

11. The film of claim 10 wherein the optical element comprises a plano-convex lens.

12. The film of claim 10 wherein the optical element comprises a lens array.

13. The film of claim 12 wherein the lens array is an exposed lens array.

14. The film of claim 12 wherein the lens array is an embedded or encapsulated lens array.

15. The film of claim 10 wherein the optical element serves as the support.

16. The film of claim 1 further comprising a dyed film layer.

17. The film of claim 1 further comprising a protective layer of crosslinked polymer atop the film.

18. A method for forming a color shifting film on a polymer support, which method comprises:

forming a reflective stack disposed adjacent to the support by;

depositing a reflective or partially reflective first layer adjacent the support,

depositing an at least partly transparent spacer layer comprising a substituted acrylamide polymer on the reflective first layer,

depositing a partially reflective or reflective second layer on the spacer layer; and

forming an image;

wherein the reflective stack has a thickness sufficient to produce an interference color.

19. The method of claim 18 comprising forming a fully reflective second layer.

20. The method of claim 18 wherein both reflective stacks are partially reflective.

21. The method of claim 18 wherein the support comprises an optical element.

22. The method of claim 21 wherein the optical element comprises a plano-convex lens.

23. The method of claim 22 wherein the optical element comprises a lens array.

24. The method of claim 23 wherein the lens array is an exposed lens array.

25. The method of claim 23 wherein the lens array is an embedded or encapsulated lens array.