Liquid crystal aligning agent and liquid crystal display device

Abstract

The invention provides a liquid crystal aligning agent and a liquid crystal display device, which has advantages of excellent liquid crystal aligning performance, good heat resistance and good light resistance. The liquid crystal aligning film has excellent electric property and the liquid crystal aligning agent keeps good stability. The liquid crystal aligning agent includes a polysiloxane (A) and a compound (B), wherein the polysiloxane (A) has an Si-X' bond (wherein, X' is a group including a structure with liquid crystal aligning power) and an Si-XI bond (wherein, XI is a group including an epoxy structure). The compound (B) has at least a structure in a group including more than two components including acetal ester structure of carboxylic acid, ketal ester structure of carboxylic acid, 1-alkyl cycloalkyl structure of carboxylic acid and tertiary butyl ester structure of carboxylic acid.

Description

technical field

[0001] The present invention relates to a liquid crystal aligning agent and a liquid crystal display element. Background technique

[0002] At present, as a liquid crystal display element, a TN type liquid crystal display element having a so-called TN type (Twisted Nematic, twisted nematic) liquid crystal cell is known, which forms a liquid crystal alignment film formed of an organic resin or the like on the surface of a substrate on which a transparent conductive film is provided. , as a substrate for liquid crystal display elements, two pieces are arranged opposite to each other, and a nematic liquid crystal layer with positive dielectric anisotropy is formed in the gap to form a box with a sandwich structure. The long axis of the liquid crystal molecules changes from one piece to the other. The substrate is continuously twisted 90 degrees to the other substrate. In addition, recently, STN (Super Twisted Nematic) type liquid crystal display element with hi...

Examples

Synthetic example 1

[0431] In a reaction vessel with a stirrer, thermometer, dropping funnel and reflux condenser, add 100.0 g of 2-(3,4-epoxycyclohexyl) ethyl trimethoxysilane, 500 g of methyl isobutyl ketone and 10.0 g of triethylamine, mixed at room temperature. Next, after adding 100 g of deionized water dropwise over 30 minutes from the dropping funnel, it was reacted at 80° C. for 6 hours while mixing under reflux. After the reaction, the organic layer was taken out, washed with 0.2% by weight of ammonium nitrate aqueous solution until the washed water was neutral, and the solvent and water were distilled off under reduced pressure to obtain polyorganosiloxane EPS-1, which was viscous Transparent liquid.

[0432] The polyorganosiloxane EPS-1 is carried out 1 In H-NMR analysis, a peak of theoretical intensity based on the oxosilyl group was obtained around chemical shift (δ) = 3.2 ppm, and it was confirmed that no side reaction occurred in the epoxy group during the reaction.

[0433] The...

Synthetic example VE-1

[0484] Into a 200 mL three-necked flask, 10.0 g of the polyorganosiloxane EPS-1 synthesized in Synthesis Example 1 and 30.28 g of methyl isobutyl ketone were added. 3.82 g of stearic acid (corresponding to 50 mol% with respect to the epoxy group that polyorganosiloxane EPS-1 has) and 0.10 g of UCAT 18X ​​(trade name, manufactured by Sunapro (KK), is the curing agent of epoxy compound Accelerator), stirred at 100°C for 48 hours to react. After the reaction, methanol was added to the reaction mixture to form a precipitate, which was dissolved in ethyl acetate, and the resulting solution was washed three times with water. After the organic layer was dried with magnesium sulfate, the solvent was distilled off to obtain 8.1 g polyorganosiloxane White powder of S-VE-1. The weight average molecular weight of S-VE-1 was 10,100.

Synthetic example VE-2

[0486] In the above Synthesis Example VE-1, except that 3.98 g of 4-n-dodecyloxybenzoic acid was used instead of stearic acid, 9.0 g of polyorganosiloxane S- White powder of VE-2. The weight average molecular weight of S-VE-2 was 9,900.

technical field

[0001] The present invention relates to a liquid crystal aligning agent and a liquid crystal display element. Background technique

[0002] At present, as a liquid crystal display element, a TN type liquid crystal display element having a so-called TN type (Twisted Nematic, twisted nematic) liquid crystal cell is known, which forms a liquid crystal alignment film formed of an organic resin or the like on the surface of a substrate on which a transparent conductive film is provided. , as a substrate for liquid crystal display elements, two pieces are arranged opposite to each other, and a nematic liquid crystal layer with positive dielectric anisotropy is formed in the gap to form a box with a sandwich structure. The long axis of the liquid crystal molecules changes from one piece to the other. The substrate is continuously twisted 90 degrees to the other substrate. In addition, recently, STN (Super Twisted Nematic) type liquid crystal display element with hi...

Examples

Synthetic example 1

[0431] In a reaction vessel with a stirrer, thermometer, dropping funnel and reflux condenser, add 100.0 g of 2-(3,4-epoxycyclohexyl) ethyl trimethoxysilane, 500 g of methyl isobutyl ketone and 10.0 g of triethylamine, mixed at room temperature. Next, after adding 100 g of deionized water dropwise over 30 minutes from the dropping funnel, it was reacted at 80° C. for 6 hours while mixing under reflux. After the reaction, the organic layer was taken out, washed with 0.2% by weight of ammonium nitrate aqueous solution until the washed water was neutral, and the solvent and water were distilled off under reduced pressure to obtain polyorganosiloxane EPS-1, which was viscous Transparent liquid.

[0432] The polyorganosiloxane EPS-1 is carried out 1 In H-NMR analysis, a peak of theoretical intensity based on the oxosilyl group was obtained around chemical shift (δ) = 3.2 ppm, and it was confirmed that no side reaction occurred in the epoxy group during the reaction.

[0433] The...

Synthetic example VE-1

[0484] Into a 200 mL three-necked flask, 10.0 g of the polyorganosiloxane EPS-1 synthesized in Synthesis Example 1 and 30.28 g of methyl isobutyl ketone were added. 3.82 g of stearic acid (corresponding to 50 mol% with respect to the epoxy group that polyorganosiloxane EPS-1 has) and 0.10 g of UCAT 18X ​​(trade name, manufactured by Sunapro (KK), is the curing agent of epoxy compound Accelerator), stirred at 100°C for 48 hours to react. After the reaction, methanol was added to the reaction mixture to form a precipitate, which was dissolved in ethyl acetate, and the resulting solution was washed three times with water. After the organic layer was dried with magnesium sulfate, the solvent was distilled off to obtain 8.1 g polyorganosiloxane White powder of S-VE-1. The weight average molecular weight of S-VE-1 was 10,100.

Synthetic example VE-2

[0486] In the above Synthesis Example VE-1, except that 3.98 g of 4-n-dodecyloxybenzoic acid was used instead of stearic acid, 9.0 g of polyorganosiloxane S- White powder of VE-2. The weight average molecular weight of S-VE-2 was 9,900.

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