Liquid Crystal Photoalignment Materials

Abstract

A charge transporting, liquid crystal photoalignment material comprising a charge transporting moiety connected through covalent chemical bonds to a surface derivatising moiety, and a photoalignment moiety connected through covalent chemical bonds to a surface derivatising moiety.

Claims

1-59. (canceled)

60. A charge transporting, liquid crystal photoalignment material comprising a charge transporting moiety connected through covalent chemical bonds to a surface derivatising moiety, and a photoalignment moiety connected through covalent chemical bonds to the surface derivatising moiety.

61. The charge transporting, liquid crystal photoalignment material of claim 60, wherein the charge transporting moiety and the photoalignment moiety are in the same molecule, or wherein the charge transporting moiety and the liquid crystal photoalignment moiety are the same moiety.

62. The charge transporting, liquid crystal photoalignment material of claim 60, which comprises a mixture of molecules at least one of which contains a charge transporting moiety covalently bonded to the surface derivatising moiety and at least one of which contains the photoalignment moiety covalently bonded to the surface derivatising moiety.

63. The charge transporting, liquid crystal photoalignment material of claim 60, wherein the charge transporting moiety is a hole transporting moiety or wherein the charge transporting moiety is an electron transporting moiety.

64. The charge transporting, liquid crystal photoalignment material of claim 60, wherein the charge transporting moiety is chosen from: ##STR00010## ##STR00011## ##STR00012##

65. The charge transporting, liquid crystal photoalignment material of claim 60, wherein the liquid crystal photoalignment moiety is chosen from a cinnamate ester, a coumarin, a quinolinone, or a benzo[b]thiinone.

66. The charge transporting, liquid crystal photoalignment material of claim 60, wherein the charge transporting moiety and the liquid crystal photoalignment moiety are the same moiety to provide a combined charge transporting and liquid crystal photoalignment moiety chosen from: ##STR00013##

67. The charge transporting, liquid crystal photoalignment material of claim 60, wherein the charge transporting moiety and the liquid crystal photoalignment moiety are connected through covalent chemical bonds.

68. The charge transporting, liquid crystal photoalignment material of claim 60, wherein one or more of the surface derivatising moieties are chosen from trihalosilanyl groups, trialkoxysilanyl groups, or Werner complexes of transition metals.

69. The charge transporting, liquid crystal photoalignment material of claim 68, wherein the surface derivatising moiety is selected from the group consisting of a trichlorosilanyl group, a triethoxysilanyl group, a trimethoxysilanyl group, and a -carboxylato--hydroxido-bis[aquadichloridoethanolchromium(III)] group, or is an alkali metal or alkaline earth metal enolate salts of 1,3-dialkyl substituted pentane-1,3-diones, or an alkali metal salts of a dialkylamine.

70. The charge transporting, liquid crystal photoalignment material of claim 60 wherein the surface derivatising moiety is connected to the charge transporting moiety by a flexible spacer chain, or is connected to the liquid crystal photoalignment moiety by a flexible spacer chain, or wherein the charge transporting moiety and the liquid crystal photoalignment moiety are in the same molecule and wherein the charge transporting moiety is connected to the liquid crystal photoalignment moiety by a flexible spacer chain.

71. A method for forming charge transporting, liquid crystal photoalignment layer comprising immersing a glass or similar substrate into a solvent solution of material comprising a charge transporting moiety connected through covalent chemical bonds to a surface derivatising moiety and a liquid crystal photoalignment moiety connected through covalent chemical bonds to the surface derivatising moiety and then withdrawing the substrate from the solvent solution, optionally rinsing the substrate with water, and drying the substrate.

72. The method of claim 71, wherein the solvent is an alcohol.

73. The method of claim 71, wherein the method further comprises heat curing the charge transporting, liquid crystal photoalignment layer after withdrawing the substrate from the solvent solution.

74. The method of claim 71, wherein the method further comprises exposing the charge transporting, liquid crystal photoalignment layer to plane polarised ultraviolet radiation.

75. The method of claim 73, wherein the method further comprises at least one additional step of immersing the substrate into the solvent solution and heat curing after withdrawing the substrate from the solvent solution.

76. The method of claim 75, wherein the method further comprises exposing the charge transporting, liquid crystal photoalignment layer to plane polarised ultraviolet radiation.

77. The method of claim 74, wherein the method further comprises at least one additional step of exposing the charge transporting, liquid crystal photoalignment layer to plane polarised ultraviolet radiation.

78. The method of claim 75, wherein the molar ratio of the charge transporting moiety to the liquid crystal photoalignment moiety is varied during successive immersion cycles.

79. A charge transporting, liquid crystal photoalignment layer produced by the method of claim 71.

80. A charge transporting layer fabricated by first forming the charge transporting, liquid crystal photoalignment layer of claim 60, then coating a layer of a charge transporting reactive mesogen material onto the liquid crystal photoalignment layer, then crosslinking the charge transporting reactive mesogen.

81. The charge-transporting layer of claim 80, wherein the layer has a uniformly aligned liquid crystalline structure.

82. The charge-transporting layer of claim 80, wherein the layer has a uniformly aligned nematic structure.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0036] A full and enabling disclosure of the present disclosure is provided in the specification, including reference to the accompanying figures, in which:

[0037] FIG. 1 illustrates a prior art electroluminescent device;

[0038] FIG. 2 illustrates the structure of tris[4-(trichlorosilyl)phenyl]amine;

[0039] FIG. 3 illustrates monolayer structure on a substrate after curing;

[0040] FIG. 4 illustrates a structure containing multiple molecular layers obtained after several cycles;

[0041] FIGS. 5-9 illustrate examples of surface derivatising, materials that can be used to form hole transporting photoalignment layers;

[0042] FIG. 10 illustrates an example of a surface derivatising, materials that can be used to form an electron transporting photoalignment layer;

[0043] FIG. 11 illustrates the structures of the photoalignment layer formed by two application and cure cycles of the material of FIG. 5;

[0044] FIGS. 12 and 13 illustrate two compounds used to form a hole transporting photoalignment layer;

[0045] FIGS. 14-16 illustrate examples of hole transporting materials; and

[0046] FIGS. 17-18 illustrate examples of photoalignment materials.

[0047] Repeat use of reference characters in the present specification and drawings is intended to represent the same or analogous features or elements of the present invention,