JPH0749584B2 - Liquid crystal composition and display device using the composition - Google Patents

Description

The present invention relates to a color liquid crystal composition having excellent light resistance and a display device.

(Prior Art) A display device utilizing the guest-host effect in which a dichroic dye is added to liquid crystal has 1) a wide viewing angle 2) various display colors can be easily realized by selecting a dye 3) a polarizing plate Since it is not always necessary and has a feature that bright display is possible, it is attracting attention as a display element particularly suitable for medium to large display.

(Problems to be Solved by the Invention) However, conventionally, it has been difficult for a display device utilizing a guest-host effect in which a dichroic dye is added to liquid crystal to simultaneously satisfy high contrast, long life and various hues. This is due to the fact that there are few dichroic dyes that have both excellent dichroism and light resistance, and when different types of dyes are blended, photodegradation of one of the dyes, especially photodegradation due to ultraviolet rays, is often accelerated. Therefore, the light resistance is lower than that when the dye is used alone. The deterioration due to the light thus generated is observed as discoloration or fading, and there is a problem in that it is measured as an increase in current consumption. Therefore, conventionally, for a variety of hues for which it is necessary to mix yellow-based, red-based, and blue-based dichroic dyes such as black, brown, and dark blue,
In particular, it is difficult to achieve both contrast and long life. An object of the present invention is to provide a color liquid crystal composition and a display device capable of solving the above conventional problems.

(Means for Solving the Problems) As a result of intensive studies to achieve such an object, the present inventors have found a liquid crystal composition having both excellent contrast and life, and completed the present invention. That is, the present invention relates to a liquid crystal substance and the following general formula [I] (In the formula, X ¹ represents a hydrogen atom or a halogen atom, and m is 1 to
2 is shown. X ² is a hydrogen atom, a halogen atom, or a group represented by the following formula [II] [In the formula [II], R ¹ and R ^{2 each} have a hydrogen atom, an alkyl group, an alkoxyalkyl group, or a cyclohexyl group which may have a substituent of an alkyl group, or an alkyl group, or an alkoxy group which has a substituent. It shows a good phenyl group. ) Is represented. n
Represents 1 to 2, provided that X ² is In the case of, n represents 1. ] At least one quinophthalone-based dichroic dye represented by the following general formula [III] (In the formula, R ³ represents a hydrogen atom, a halogen atom, an alkyl group, an alkoxyalkyl group, an alkoxy group or a cycloalkyl group which may have a substituent, and X ³ represents a hydrogen atom, a halogen atom or a substituent. An anthraquinone-based dichroic dye represented by formula (IV) (In the formula, R ⁴ and R ⁵ represent a hydrogen atom, a halogen atom, an alkyl group, an alkoxyalkyl group, an alkoxy group or a cycloalkyl group which may have a substituent.) Anthraquinone dichroism At least one of dyes and the following general formula [V] (In the formula, R ⁶ represents a hydrogen atom, a halogen atom, an alkyl group, an alkoxyalkyl group, an alkoxy group or a cycloalkyl group which may have a substituent, and R ⁷ represents a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group. An alkyl group, an alkoxy group, a cycloalkyl group which may have a substituent, or a phenyl group which may have a substituent such as an alkyl group and an alkoxy group). A liquid crystal composition comprising one kind,
Further, the gist is a liquid crystal display device in which at least one of the liquid crystal compositions is carried between transparent electrode substrates.

To explain the present invention in more detail, examples of X ¹ and X ² in the general formula [I] shown above include a hydrogen atom; a halogen atom such as a fluorine atom, a chlorine atom and a bromine atom, and X ² is represented by the formula: R ¹ and R ² when represented by [II] are hydrogen atoms; linear groups such as methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, octyl group, nonyl group and dodecyl group Or a branched alkyl group; a linear or branched alkoxyalkyl group such as methoxymethyl group, butoxymethyl group, methoxypropyl group, ethoxyethyl group, butoxyethyl group; propylcyclohexyl group, butylcyclohexyl group, pentyl A cyclohexyl group which may have a substituent of a linear or branched alkyl group such as a cyclohexyl group, a hexylcyclohexyl group, an octylcyclohexyl group; A phenyl group which may have a substituent such as a linear or branched alkyl group such as an phenyl group, an ethylphenyl group, a butylphenyl group, an octylphenyl group, a butoxyphenyl group and an octyloxyphenyl group, and an alkoxy group. Examples of R ^{3 to} R ⁴ in the general formulas [III] to [V] shown above include a hydrogen atom; a halogen atom such as a fluorine atom, a chlorine atom and a bromine atom; a methyl group, an ethyl group,
A linear or branched alkyl group such as propyl group, butyl group, pentyl group, hexyl group, octyl group, nonyl group, dodecyl group; methoxymethyl group, butoxymethyl group,
Linear or branched alkoxyalkyl groups such as methoxypropyl group, ethoxyethyl group, butoxyethyl group; linear or branched groups such as methoxy group, ethoxy group, propoxy group, butoxy group, pentoxy group, octoxy group, etc. A linear alkoxy group; a cycloalkyl group which may have a substituent such as a linear or branched alkyl group such as a propylcyclohexyl group, a butylcyclohexyl group, a pentylcyclohexyl group, a hexylcyclohexyl group and an octylcyclohexyl group, Examples of X ³ in the general formula [III] shown above include a hydrogen atom; a halogen atom such as a fluorine atom, a chlorine atom and a bromine atom; an alkoxy such as a methoxycarbonyl group, an ethoxycarbonyl group, a butoxycarbonyl group and an octyloxycarbonyl group. Carbonyl group, butylphenoxycarbonyl group, octa Ruphenoxycarbonyl group, butoxyphenoxycarbonyl group and other alkyl groups or alkoxy groups and other phenoxycarbonyl groups, which may have a substituent, trans-4-butylcyclohexyloxycarbonyl group, trans-4-octylcyclohexyloxycarbonyl group Examples thereof include a carboxylic acid ester group such as a cyclohexyloxycarbonyl group which may have a substituent such as a linear or branched alkyl group such as, and R ⁷ in the above general formula [V] is a hydrogen atom. A halogen atom such as a fluorine atom, a chlorine atom and a bromine atom; a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group,
Linear or branched alkyl group such as octyl group, nonyl group, dodecyl group; linear or branched alkyl group such as methoxymethyl group, butoxymethyl group, methoxypropyl group, ethoxyethyl group, butoxyethyl group Alkoxyalkyl group; linear or branched alkoxy group such as methoxy group, ethoxy group, propoxy group, butoxy group, pentoxy group, octoxy group; propylcyclohexyl group, butylcyclohexyl group, pentylcyclohexyl group, hexylcyclohexyl group, Cycloalkyl group which may have a substituent such as linear or branched alkyl group such as octylcyclohexyl group; ethylphenyl group, butylphenyl group, octylphenyl group, butoxyphenyl group, octyloxyphenyl group, etc. Which may have a substituent of an alkyl group or an alkoxy group of It includes group.

The liquid crystal substance used in the present invention has the following general formula (In the formula, R ⁸ and R ⁹ are an alkyl group, an alkoxyalkyl group,
Alkoxy group, alkylphenyl group, alkoxyalkylphenyl group, alkoxyphenyl group, alkylcyclohexyl group, alkoxyalkylcyclohexyl group, alkylcyclohexylphenyl group, cyanophenyl group,
Cyano group, halogen atom, alkoxycarbonyl group, alkoxyalkoxycarbonyl group, alkylphenoxycarbonyl group, alkoxyalkylphenoxycarbonyl group, alkoxyphenoxycarbonyl group, alkylcyclohexyloxycarbonyl group, alkoxycyclohexyloxycarbonyl group, alkylcyclohexylphenoxycarbonyl group, cyano Phenoxycarbonyl group, halogen phenoxycarbonyl group, alkylphenylalkyl group, alkoxyalkylphenylalkyl group, alkoxyphenylalkyl group, alkylcyclohexylalkyl group, alkoxyalkoxycyclohexylalkyl group, alkylcyclohexylphenylalkyl group, cyanophenylalkyl group, alkyl chain,
It may have an optically active center in the alkoxy chain. or,
The phenyl group or phenoxy group in R ⁸ and R ⁹ may be substituted with a halogen atom such as a fluorine atom or a chlorine atom. X ⁴ represents a hydrogen atom or a halogen atom such as a fluorine atom and a chlorine atom. And liquid crystal substances such as a single substance of the compound represented by the formula) or a mixture thereof. Further, the liquid crystal mixture may contain additives such as an optically active substance such as cholesteryl nonanoate, an ultraviolet absorber and an antioxidant.

The liquid crystal composition of the present invention can be easily prepared by dissolving the dyes represented by the structural formulas [I] to [V] in the liquid crystal substance.

The liquid crystal composition thus prepared is supported between at least one of the transparent electrode substrates so that a display device applying the guest-host effect [Shouichi Matsumoto, Ichino Tsunoda,
"Latest LCD Technology" Industrial Research Group 34 (1983) JLFergaso
n, SID85 Digest68 (1985), etc.] can be configured.

〔Example〕

Hereinafter, the present invention will be specifically described by way of examples, but the present invention is not limited to the following examples as long as the gist thereof is not exceeded.

Example 1 Dye represented by the following structural formula [I-1] And a dye represented by the following structural formula [III-1] [III-1] R ³ : C ₄ H ₉ (n) R ¹⁰ : C ₄ H ₉ (n) 1.15 g and a dye represented by the following structural formula [IV-1] [IV-1] R ⁴ : C ₄ H ₉ (n) R ⁵ : CH ₃ 1.14 g and dyes [V-1] and [V-2] represented by the following structural formulas Was dissolved in 100 g of a liquid crystal mixture containing a phenylcyclohexane compound as a main component, which is commercially available under the trade name ZLI-1565 (manufactured by E.MERCK) to prepare Liquid Crystal Composition-I. This is coated with a polyimide-based resin and cured, and then rubbed to form a homogeneously oriented glass plate with a transparent electrode. The glass plate is sealed in a cell having a gap of 9 μm configured so that the orientation-treated surfaces face each other. Measure the absorbance A for parallel linearly polarized light and the absorbance A ⊥ for vertical linearly polarized light, and use the following formula As a result of calculating the order parameter S from, it was 0.74 and 0.68 at 578 nm and 452 nm, respectively. As a result of carrying out a light resistance test on a cell in which the liquid crystal composition-I is enclosed, with a fade meter (carbon arc light source),
Hue change after 200 hours: ΔE ^* (L ^* a ^* b ^* method) is 3
The increase rate of the current value is I / I ₀ (applied voltage: 5V, 32H
z) was 2.3, and the change in absorbance at each absorption peak (578 nm, 452 nm) was 3% or less.

Example 2 Dyes [I-2] and [I-3] represented by the following structural formulas [I-2] R ¹ : C ₄ H ₉ (n) R ² : C ₄ H ₉ (n) 0.62g [I-3] R ¹ : HR ² : C ₈ H ₁₇ (n) 0.33g and the following structure The dyes represented by the formulas [III-1] and [III-
2] [III-1] R ³ : C ₄ H ₉ (n) R ¹⁰ : C ₄ H ₉ (n) 0.75g [III-2] R ³ : C ₇ H ₁₅ (n) R ¹⁰ : C ₄ H ₉ ( n) 0.49 g and a dye represented by the following structural formula [IV-2] [IV-2] R ⁴ : C ₆ H ₁₃ (n) R ⁵ : CH ₃ 1.33 g and a dye represented by the following structural formula [V-3] Was dissolved in 100 g of a liquid crystal mixture containing a phenylcyclohexane compound as a main component, which is commercially available under the trade name ZLI-1565 (manufactured by E.MERCK) to prepare a liquid crystal composition-II. This is coated with a polyimide-based resin and cured, and then rubbed to form a homogeneously oriented glass plate with a transparent electrode. The glass plate is sealed in a cell having a gap of 9 μm configured so that the orientation-treated surfaces face each other. Measure the absorbance A for parallel linearly polarized light and the absorbance A ⊥ for vertical linearly polarized light, and use the following formula As a result of calculating the order parameter S from the results, it was 0.74 and 0.59 at 575 nm and 448 nm, respectively. As a result of carrying out a light resistance test with a fade meter (carbon arc light source) on the cell in which the liquid crystal composition-II is enclosed,
Hue change after 200 hours: ΔE ^* (L ^* a ^* b ^* method) is 3
The increase rate of the current value is I / I ₀ (applied voltage: 5V, 32H
z) was 2.4, and the change in absorbance at each absorption peak (575 nm, 448 nm) was 3% or less.

Example 3 Dyes [I-4] and [I-5] represented by the following structural formulas And a dye represented by the following structural formula [III-3] [III-3] R ³ : C ₈ H ₁₇ (n) R ¹⁰ : C ₆ H ₁₃ (n) 1.05 g and dyes [IV-3] and [IV-4] represented by the following structural formulas [IV-3] _{^{R 4: C 7 H 15 (}} n) R 5: CH 3 0.75g [IV-4] _{^{R 4: C 6 H 13 (}} n) R 5: C 4 H 9 (n) 0.73g and Dyes [V-2] and [V-4] represented by the following structural formulas Was dissolved in 100 g of a liquid crystal mixture containing a phenylcyclohexane-based compound as a main component, which is commercially available under the trade name ZLI-1565 (manufactured by E.MERCK) to prepare a liquid crystal composition-III.
This is coated with a polyimide-based resin and cured, and then rubbed to form a homogeneously oriented glass plate with a transparent electrode. The glass plate is sealed in a cell having a gap of 9 μm configured so that the orientation-treated surfaces face each other. Measure the absorbance A for parallel linearly polarized light and the absorbance A ⊥ for vertical linearly polarized light, and use the following formula As a result of calculating the order parameter S from the results, it was 0.74 and 0.67 at 580 nm and 447 nm, respectively. As a result of performing a light resistance test on a cell in which the liquid crystal composition-III is enclosed with a fade meter (carbon arc light source), a hue change after 200 hours: ΔE ^* (L ^* a ^* b ^* method)
Is 3.7 or less, and the rate of increase in current value I / I ₀ (applied voltage: 5 V,
32Hz) is 3.2, and each absorption peak (580nm, 447nm)
The absorbance change of was less than 4%.

Example 4 Dyes [I-6] and [I-7] represented by the following structural formulas And a dye represented by the following structural formula [III-4] [III-4] R ³ : C ₄ H ₉ (n) X ³ : Cl 1.24 g and a dye represented by the following structural formula [IV-2] [IV-2] R ⁴ : C ₆ H ₁₃ (n) R ⁵ : CH ₃ 1.00 g and dyes [V-1] and [V-5] represented by the following structural formulas
And [V-6] [V-1] _{^{R 6: C 4 H 9 (}} n) R 7: H 0.93g [V-1] _{^{R 6: C 6 H 13 (}} n) R 7: H 0.77g [V-1] R ^6: A liquid crystal composition was prepared by dissolving 0.85 g of C ₇ H ₁₅ (n) R ⁷ : H in 100 g of a liquid crystal mixture containing a phenylcyclohexane compound as a main component, which is commercially available under the trade name ZLI-1565 (manufactured by E.MERCK). -IV was adjusted. This is coated with a polyimide-based resin and cured, and then rubbed to form a homogeneously oriented glass plate with a transparent electrode. The glass plate is sealed in a cell having a gap of 9 μm configured so that the orientation-treated surfaces face each other. Measure the absorbance A for parallel linearly polarized light and the absorbance A ⊥ for vertical linearly polarized light, and use the following formula As a result of calculating the order parameter S from the results, it was 0.74 and 0.69 at 577 nm and 449 nm, respectively. As a result of carrying out a light resistance test with a fade meter (carbon arc light source), the cell in which the liquid crystal composition-IV is enclosed,
Hue change after 200 hours: ΔE ^* (L ^* a ^* b ^* method) is 3
The increase rate of the current value is I / I ₀ (applied voltage: 5V, 32H
z) was 2.6, and the change in absorbance at each absorption peak (577 nm, 449 nm) was 3% or less.

Example 5 Dye represented by the following structural formula [I-8] And the dyes [III-5] and [III-] represented by the following structural formulas
6] [III-5] ^{_{R 3: C 5 H 11 (}} n) R 10: C 6 H 13 (n) 0.66g [III-6] ^{_{R 3: C 6 H 13 (}} n) R 10: C 4 H 9 ( n) 0.52 g and dyes [IV-2] and [IV-5] represented by the following structural formulas [IV-2] ^{_{R 4: C 6 H 13 (}} n) R 5: CH 3 0.66g [IV-5] ^{_{R 4: C 6 H 13 (}} n) R 5: C 6 H 13 (n) 0.75g and Dyes [V-7] and [V-8] represented by the following structural formulas Was dissolved in 100 g of a liquid crystal mixture containing a phenylcyclohexane compound as a main component, which is commercially available under the trade name ZLI-1840 (manufactured by E.MERCK) to prepare a liquid crystal composition-V. This is coated with a polyimide-based resin and cured, and then rubbed to form a homogeneously oriented glass plate with a transparent electrode, which is enclosed in a gap 9 μm cell configured so that the orientation-treated surfaces face each other. Measure the absorbance A for parallel linearly polarized light and the absorbance A ⊥ for vertical linearly polarized light, and use the following formula As a result of calculating the order parameter S from, the results were 0.74 and 0.67 at 585 nm and 449 nm, respectively. As a result of carrying out a light resistance test with a fade meter (carbon arc light source), the cell in which the liquid crystal composition-IV is enclosed,
Hue change after 200 hours: ΔE ^* (L ^* a ^* b ^* method) is 3.5
The increase rate of the current value is I / I ₀ (applied voltage: 5V, 32H
z) was 3.3, and the change in absorbance at each absorption peak (585 nm, 449 nm) was 3% or less.

(Effects of the Invention) As is clear from the above results, the color liquid crystal composition containing the combination of the specific dichroic dyes of the present invention and the liquid crystal display device using the liquid crystal composition are added with the dichroic dyes. A variety of hues such as black, brown, dark blue, etc. that utilize the guest-host effect and have excellent light resistance, and particularly require the blending of three types of dichroic dyes of yellow, red, and blue With respect to the above, it is possible to achieve both the contrast and the long service life, which have been conventionally difficult to achieve, with a remarkable industrially valuable effect.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location C09B 25/00 Z C09K 19/60 F 9279-4H H 9279-4H E 9279-4H // G02F 1 / 13 500

Claims (2)

[Claims] 1. A liquid crystal substance and the following general formula [I]: [In the formula, X ¹ represents a hydrogen atom or a halogen atom, and m is 1 to
2 is shown. X ² is a hydrogen atom, a halogen atom, or a group represented by the following formula [II] (In the formula [II], R ¹ and R ^{2 each} have a hydrogen atom, an alkyl group, an alkoxyalkyl group, an optionally substituted cyclohexyl group or an alkyl group, or an alkoxy group. Represents a good phenyl group). n
Indicates 1 to 2, provided that X ² is In the case of, n represents 1. ] At least one quinophthalone-based dichroic dye represented by the following general formula [III] (In the formula, R ³ represents a hydrogen atom, a halogen atom, an alkyl group, an alkoxyalkyl group, an alkoxy group or a cycloalkyl group which may have a substituent, and X ³ represents a hydrogen atom, a halogen atom or a substituent. An anthraquinone-based dichroic dye represented by the following general formula [IV] (In the formula, R ⁴ and R ⁵ represent a hydrogen atom, a halogen atom, an alkyl group, an alkoxyalkyl group, an alkoxy group or a cycloalkyl group which may have a substituent.) Anthraquinone dichroism At least one of dyes and the following general formula [V] (In the formula, R ⁶ represents a hydrogen atom, a halogen atom, an alkyl group, an alkoxyalkyl group, an alkoxy group or a cycloalkyl group which may have a substituent, and R ⁷ represents a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group. An alkyl group, an alkoxy group, a cycloalkyl group which may have a substituent, or a phenyl group which may have a substituent such as an alkyl group and an alkoxy group). A liquid crystal composition comprising one kind. 2. A liquid crystal display device having a liquid crystal composition supported between electrode substrates, at least one of which is transparent, wherein the liquid crystal composition according to claim 1 is used as the liquid crystal composition. Display element.