# US 8,772,383 B2 · Material for alignment layer of liquid crystal display > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,772,383 B2 - Document ID: US8772383B2 - Status: Granted - Kind: B2 - Application number: 13/635,405 - Filed: 2012-08-03 - Published: 2014-01-23 - Granted: 2014-07-08 - Earliest claimed: 2012-08-03 - Assignees: Shenzhen China Star Optoelectronics Technology Co., Ltd. - Applicants: Xinhui Zhong; Hongji Huang; Kuancheng Lee - Inventors: Xinhui Zhong; Hongji Huang; Kuancheng Lee - Web page: https://patentgrep.com/patent/US8772383B2 ## CPC - C08L 79/08: Polyimides; Polyester-imides; Polyamide-imides; Polyamide acids or similar polyimide precursors - C09D 179/08: Polyimides; Polyester-imides; Polyamide-imides; Polyamide acids or similar polyimide precursors - C08G 73/1042: {Copolyimides derived from at least two different tetracarboxylic compounds or two different diamino compounds} - C08G 73/1067: {Wholly aromatic polyimides, i.e. having both tetracarboxylic and diamino moieties aromatically bound} - C08G 73/1082: {wholly aromatic in the tetracarboxylic moiety} - G02F 1/133707: {Structures for producing distorted electric fields, e.g. bumps, protrusions, recesses, slits in pixel electrodes} - G02F 1/133723: {Polyimide, polyamide-imide} - G02F 1/133753: {with different alignment orientations or pretilt angles on a same surface, e.g. for grey scale or improved viewing angle} - G02F 1/133788: {by light irradiation, e.g. linearly polarised light photo-polymerisation} - G02F 1/133715: {by first depositing a monomer} - C08L: COMPOSITIONS OF MACROMOLECULAR COMPOUNDS (compositions based on polymerisable monomers C08F, C08G; artificial filaments or fibres D01F; textile treating compositions D06) - C09D: COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR (cosmetics A61K; processes for applying liquids or other fluent materials to surfaces, in general, B05D; staining wood B27K5/02; glazes or vitreous enamels C03C; natural resins, French polish, drying-oils, driers, turpentine, per se, C09F; polishing compositions other than French polish, ski waxes C09G; adhesives or use of materials as adhesives C09J; materials for sealing or packing joints or covers C09K3/10; materials for stopping leaks C09K3/12; processes for the electrolytic or electrophoretic production of coatings C25D) - C08G: MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS - G02F: OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS ## Abstract The present invention provides a material for alignment layer of liquid crystal display, which includes a solvent and a polymer dissolved in the solvent. The polymer includes a backbone and a first side chain linked to the backbone. The first side chain has a stronger lateral dipole moment. The material for alignment layer of liquid crystal display is characterized in that a first side chain that contains both a flexible chain segment and rigid chain segment is linked to the backbone of the polymer and the first side chain has a stronger lateral dipole moment, making it taking a rotation or tilting motion under the application of an electric field so as to effect alignment of the liquid crystal molecules in the pre-tilt angle. ## Claims ### Claim 1 A material for alignment layer of liquid crystal display, comprising a solvent and a polymer dissolved in the solvent, the polymer comprising a backbone and a first side chain linked to the backbone, the first side chain having a stronger lateral dipole moment; wherein the backbone of the polymer comprises a structure of polyimide or polyamic acid, which has the following formula: wherein the ring A and ring B are benzene rings, aromatic rings, or fused-ring aromatic compounds; X and Y are linking moieties; and n and m represent the degree of polymerization, the values of n and m being in a range of 20 to 2000. ### Claim 2 (depends on 1) The material for alignment layer of liquid crystal display as claimed in claim 1, wherein X and Y are represented by the following formulas: the value of n and m are in the range of 50 to 500 and R is a terminal moiety. ### Claim 3 (depends on 1) The material for alignment layer of liquid crystal display as claimed in claim 1, wherein the first side chain of the polymer comprises two obviously distinguished segmented structures, which are respectively a flexible chain segment linked to the backbone and a rigid chain segment linked to the flexible chain segment, the rigid chain segment having a stronger lateral dipole moment. ### Claim 4 (depends on 3) The material for alignment layer of liquid crystal display as claimed in claim 3, wherein the first side chain of the polymer has one of the following formulas: wherein in formulas II and III, M is the flexible chain linked to the backbone and is formed by a molecular main chain composed of 3-25 C, O, S, N, and Si atoms; ring A, ring B and ring C are five- or six-membered rings or ring structures with or without N, S, and O heteroatoms; rings A, B, and C are identical or different, rings A, B and C being saturated, unsaturated, or aromatic rings; Z is substituted moiety on rings A, B and C and can be identical or different, being mono-substituted or polysubstituted on a single ring is allowable, Z is —CN, —F, —Cl, —Br, —NCS, —CF3, —OCF3, or —OCHF2; R is the terminal moiety of the first side chain which is a carbon chain composed of H or 1-8 carbons. ### Claim 5 (depends on 1) The material for alignment layer of liquid crystal display as claimed in claim 1, wherein the first side chain of the polymer takes 5-40% molecular weight of the polymer. ### Claim 6 (depends on 1) The material for alignment layer of liquid crystal display as claimed in claim 1, wherein the polymer further comprises one, two or all of a second side chain, a third side chain, and a fourth side chain. ### Claim 7 (depends on 6) The material for alignment layer of liquid crystal display as claimed in claim 6, wherein the second side chain is a flexible side chain, which is formed by a molecular main chain composed of 3-25 C, O, S, N, or Si atoms; the third side chain is a polar side chain, which is hydroxyl, carboxyl, or a ring structure contains hydroxyl or carboxyl; the fourth side chain is a rigid side chain composed of chain segments that contain 2-3 rings. ### Claim 8 (depends on 1) The material for alignment layer of liquid crystal display as claimed in claim 1, wherein the polymer takes 1-20% total weight of the material for alignment layer. ### Claim 9 (depends on 1) The material for alignment layer of liquid crystal display as claimed in claim 1, wherein the solvent is selected from one of or a mixture of multiple ones of N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, γ-butyrolactone, ethylene glycol mono-n-butyl ether, and dimethylacetamide. ### Claim 10 A material for alignment layer of liquid crystal display, comprising a solvent and a polymer dissolved in the solvent, the polymer comprising a backbone and a first side chain linked to the backbone, the first side chain having a stronger lateral dipole moment; wherein the backbone of the polymer comprises a structure of polyimide or polyamic acid, which has the following formula: wherein the ring A and ring B are benzene rings, aromatic rings, or fused-ring aromatic compounds; X and Y are linking moieties; and n and m represent the degree of polymerization, the values of n and m being in a range of 20 to 2000; wherein X and Y are represented by the following formulas: the value of n and m are in the range of 50 to 500; wherein the first side chain of the polymer comprises two obviously distinguished structures which are respectively a flexible chain linked to the backbone and a rigid chain linked to the flexible chain, the rigid chain having a stronger lateral dipole moment; wherein the first side chain of the polymer has one of the following formulas: wherein in formulas II and III, M is the flexible chain linked to the backbone and is formed by a molecular main chain composed of 3-25 C, O, S, N, and Si atoms; ring A, ring B and ring C are five- or six-membered rings or ring structures with or without N, S, and O heteroatoms; rings A, B, and C are identical or different, rings A, B and C being saturated, unsaturated, or aromatic rings; Z is substituted moiety on rings A, B and C and can be identical or different, being mono-substituted or polysubstituted on a single ring is allowable, Z is —CN, —F, —Cl, —Br, —NCS, —CF3, —OCF3, or —OCHF2; R is the terminal moiety of the first side chain which is a carbon chain composed of H or 1-8 carbons; wherein the first side chain of the polymer takes 5-40% molecular weight of the polymer; wherein the polymer takes 1-20% total weight of the material for alignment layer; and wherein the solvent is selected from one of or a mixture of multiple ones of N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, γ-butyrolactone, ethylene glycol mono-n-butyl ether, and dimethylacetamide.