Glassy chiral-nematic liquid crystals and optical devices containing same

1. A glassy chiral-nematic liquid crystal composition comprising a compound having a 1, 3, 5-benzenetricarbonyl central moiety, said composition being characterized by a morphologically stable cholesteric phase and said compound having the structural formula

wherein each N represents a nematic group connected to said central moiety by a carboxylic ester linkage and Ch represents a chiral group connected to said central moiety by a carboxylic ester linkage.

2. The composition of claim 1 wherein said nematic group N includes a biphenyl or a terphenyl moiety.

3. The composition of claim 2 wherein said nematic group N is a 4-(1-propylene-3-oxy)-benzoic acid 4′-cyanobiphenyl-4-yl ester group or a 3-(4′-cyano-p-terphenyloxy)-1propyl group.

4. The composition of claim 1 wherein said nematic group N includes a coumarin moiety.

5. The composition of claim 4 wherein said nematic group N is a 4′-(6-hexyleneoxy)-[1,1′-biphenyl]-4-carboxylate acid, 4-(6-coumarin) ester.

6. The composition of claim 1 wherein said nematic group N includes a naphthyl moiety.

7. The composition of claim 1 wherein said chiral group Ch includes an ether or an ester of a chiral alcohol.

8. The composition of claim 1 wherein said chiral group Ch es an amide of a chiral amine.

9. The composition of claim 8 wherein said chiral group Ch es an (S)— or an (R)-1-(phenylethyl) amide moiety.

10. The composition of claim 1 wherein said chiral group Ch es a (+)-estrone ether or ester moiety.

11. The composition of claim 1 wherein said chiral group Ch is an (S)-2′-4-[1-(2-naphthyl)ethoxymethyl]phenyl-6′-ethyleneoxy-naphthalene group.

12. The composition of claim 1 wherein said chiral and nematic groups are selected from, respectively, the following groups of chiral Ch and nematic N groups

wherein n represents an integer from 2 to 6 and m represents an integer from 1 to 6.

wherein n represents an integer from 2 to 6 and m represents an integer from 1 to 6.

13. The composition of claim 1 wherein said compound is selected from the group consisting of 1,3,5-benzenetricarboxylic acid, 1,3-bis-{3-[4-(4′-cyano-biphenyl-4-yloxycarbonyl)-phenoxy]-propyl ester}, 5-{[4-[[4-[(R)-(+)-[(phenylethyl)]benzamide]-1-oxy]benzoate-1-oxy] ethyl ester} (I-R), 1,3,5-benzenetricarboxylic acid, 1,3-bis-{3-[4-(4′cyano-biphenyl-4-yloxycarbonyl)phenoxy]-propyl ester}, 5-{[4-[[4-[(S)-(−)-1-(phenylethyl)]benzamide]-1-oxy]benzoate-1-oxy] ethyl ester} (I-S), and mixtures thereof.

14. The composition of claim 1 wherein said compound is selected from the group consisting of 1,3,5-benzenetricarboxylic acid, 1,3-bis-{4-[(6-coumarin)-yloxycarbonyl]-4′-biphenoxy] hexyl ester}, 5-{[4-[[4-[(R)-(+)-1-(phenylethyl)]benzamide]-1-oxy]benzoate-1-oxy] ethyl ester} (II-R), 1,3,5-benzenetricarboxylic acid, 1,3-bis-{4-[(6-coumarin)-yloxycarbonyl]-4′-biphenoxy] hexyl ester}, 5-{[4-[[4-[(S)-(+)-1-(phenylethyl)]benzamide]-1-oxy]benzoate-1-oxy] ethyl ester} (II-S), and mixtures thereof.

15. The composition of claim 1 wherein said compound is selected from the group consisting of 1,3,5-benzenetricarboxylic acid, 1,3-bis-{[6-(4′-cyanophenyl) 2 -naphthyloxy]-1-propyl ester}, 5-{6-[1-[1-(R)-(2-naphthylethyl)oxo]benzyl9-2-naphthyloxy]-1-propyl ester} (III-R), 1,3,5-benzenetricarboxylic acid, 1,3-bis-{[6-(4′-cyanophenyl) 2-naphthyloxy]-1-propyl ester}, 5-{6-[1-[1-(S)-(2-naphthylethyl)oxo]benzyl]-2-naphthyloxy]-1-propyl ester} (III-S), and mixtures thereof.

16. The composition of claim 1 further comprising a glassy nematic liquid crystal compound selected from the group consisting of 1,3,5-tris-{3-[4-(4′cyano-biphenyl-4-yloxycarbonyl)-phenoxy]-propyl ester} (IV) and 1,3,5-tris-{4-[(6-coumarin)-yloxycarbonyl]-4′-biphenoxy] hexyl ester} (V).

17. An optical device formed from at least one glassy chiral-nematic liquid crystal composition comprising a compound having a 1, 3, 5-benzenetricarbonyl central moiety, said composition being characterized by a morphologically stable cholesteric phase and said compound having the structural formula

wherein each N represents a nematic group connected to said central moiety by a carboxylic ester linkage and Ch represents a chiral group connected to said central moiety by a carboxylic ester linkage.

18. The optical device of claim 17 wherein said nematic group N includes a biphenyl or terphenyl moiety.

19. The optical device of claim 18 wherein said nematic group N is a 4-(1-propylene-3-oxy)-benzoic acid 4′-cyanobiphenyl-4-yl ester group or a 3-(4′-cyano-p-terphenyloxy)-1-propyl group.

20. The optical device of claim 17 wherein said nematic group N includes a coumarin moiety.

21. The optical device of claim 20 wherein said nematic group N is a 4′-(6-hexyleneoxy)-[1,1′-biphenyl]-4-carboxylate acid, 4-(6-coumarin) ester.

22. The optical device of claim 17 wherein said nematic group N includes a naphthyl moiety.

23. The optical device of claim 17 wherein said chiral group Ch includes an ether or an ester of a chiral alcohol.

24. The optical device of claim 17 wherein said chiral group Ch includes an amide of a chiral amine.

25. The optical device of claim 24 wherein said chiral group Ch includes an (S)— or an (R)-1-(phenylethyl) amide moiety.

26. The optical device of claim 17 wherein said chiral group Ch includes a (+)-estrone ether or ester moiety.

27. The optical device of claim 17 wherein said chiral and nematic groups are selected from, respectively, the following groups of chiral Ch and nematic N groups

wherein n represents an integer from 2 to 6 and m represents an integer from 1 to 6.

in n represents an integer from 2 to 6 and m represents an integer from 1 to 6.

28. The optical device of claim 17 wherein said compound is selected from the group consisting of 1,3,5-benzenetricarboxylic acid, 1,3-bis-{3-[4-(4′cyano-biphenyl-4-yloxycarbonyl)-phenoxy]-propyl ester}, 5-{[4-[[4-[(R)-(+)-1-(phenylethyl)]benzamide]-1-oxy]benzoate-1-oxy] ethyl ester} (I-R), 1,3,5-benzenetricarboxylic acid, 1,3-bis-{3-[4-(4′cyano-biphenyl-4-yloxycarbonyl)-phenoxy]-propyl ester}, 5-{[4-[[4-[(S)-(−)-1-(phenylethyl)]benzamide]-1-oxy]benzoate-1-oxy] ethyl ester} (II-S), and mixtures thereof.

29. The optical device of claim 17 wherein said compound is selected from the group consisting of 1,3,5-benzenetricarboxylic acid, 1,3-bis-{4-[(6-coumarin)-yloxycarbonyl]-4′-biphenoxy] hexyl ester}, 5-{[4-[[4-[(R)-(+)-1-(phenylethyl)]benzamide]-1-oxy]benzoate-1-oxy] ethyl ester} (II-R), 1,3,5-benzenetricarboxylic acid, 1,3-bis-{4-[(6-coumarin)-yloxycarbonyl]-4′-biphenoxy] hexyl ester}, 5-{[4-[[4-[(S)-(+)-1-(phenylethyl)]benzamide]-1-oxy]benzoate-1-oxy] ethyl ester} (II-S), and mixtures thereof.

30. The optical device of claim 17 wherein said compound is selected from the group consisting of 1,3,5-benzenetricarboxylic acid, 1,3-bis-{[6-(4′-cyanophenyl) 2-naphthyloxy]-1-propyl ester}, 5-{6-[1-[1-(R)-(2-naphthylethyl)oxo]benzyl]-2-naphthyloxy]-1-propyl ester} (III-R), 1,3,5-benzenetricarboxylic acid, 1,3-bis-{[6-(4′-cyanophenyl) 2-naphthyloxy]-1-propyl ester}, 5-{6-[1-[1-(S)-(2-naphthylethyl)oxo]benzyl]-2-naphthyloxy]-1-propyl ester} (III-S), and mixtures thereof.

31. The optical device of claim 17 comprising a said compound having a 1,3,5-benzenetricarbonyl central moiety and a glassy nematic liquid crystal compound selected from the group consisting of 1,3,5-tris-{3-[4-(4′cyano-biphenyl-4-yloxycarbonyl)-phenoxy]-propyl ester} (IV) and 1,3,5-tris-{4-[(6-coumarin)-yloxycarbonyl]-4′-biphenoxy] hexyl ester} (V).

32. The optical device of claim 17 comprising at least one film formed from at least one said glassy chiral-nematic liquid crystal composition.

33. The optical device of claim 32 further comprising an optically clear substrate.

34. The optical device of claim 32 wherein said film further comprises a nematic liquid crystal compound.

35. The optical device of claim 17 selected from the group consisting of a circular polarizer, an optical notch filter, and a reflector.