JP2000336366A - Dichroic dye composition, guest-host type liquid crystal composition using the same, and liquid crystal display device - Google Patents

Abstract

(57) [Abstract] (with correction) [PROBLEMS] To provide a guest-host type liquid crystal element having excellent dichroism or high order parameters and excellent contrast characteristics and driving characteristics. SOLUTION: General formula I-1, for example, No. I-1-2
And the general formula II, e.g. A dichroic dye composition comprising at least one anthraquinone dichroic dye of II-2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal composition used for a display device and the like and a liquid crystal device using the same, and more particularly to a guest-host type liquid crystal composition used for a reflection type liquid crystal display device.

[0002]

2. Description of the Related Art A guest-host type liquid crystal device using a guest-host type liquid crystal composition in which a dichroic dye is mixed with a host liquid crystal material does not necessarily require a polarizer. Because of its excellent viewing angle and brightness, it has attracted attention especially for reflective displays used in portable information devices.

The display quality such as the contrast of the guest-host type liquid crystal device is determined by the dichroic or order parameter of the dichroic dye contained in the guest-host type liquid crystal composition to be used, and the coloring density of the dichroic dye. High order parameters to correlate directly with
In addition, a guest-host type liquid crystal composition having a high coloring density is required. In particular, recently, a guest-host type liquid crystal composition using a host liquid crystal composition such as a fluorine-based liquid crystal, which can be used for an active driving liquid crystal display device and has a high order parameter and a high coloring density, has been demanded.

On the other hand, a reflection type liquid crystal display device, which performs display by reflecting ambient light incident from outside without using a backlight, is considered to be used outdoors and is particularly resistant to light such as direct sunlight. Therefore, high charge retention characteristics in active driving, that is, electrical characteristics such as a voltage retention ratio are required. In addition, since the reflective liquid crystal display device does not use a backlight light source, the spectral appearance is different, for example, even under an environment with different ambient light such as under a fluorescent lamp and under an incandescent lamp, the color appearance changes little, that is, Stable color rendering is required, especially for achromatic black. For such a phenomenon of color vision constancy that the appearance of the object color does not change even if the light source is changed, it is generally considered sufficient to illuminate the object color with a smooth spectral reflectance with a light source with a smooth spectral distribution. However, in the reflection type liquid crystal display device, as described above, since it is impossible to limit the light source, the dichroic dye composition having a smooth spectral reflectance, that is, the absorption of the dichroic dye is smooth and A guest-host type liquid crystal composition is required.

[0005] However, azo dyes conventionally used in guest-host type liquid crystal compositions generally show high order parameters and smooth absorption, but have higher light stability than anthraquinone dichroic dyes. Azo dyes that can be practically used are very limited. In addition, although anthraquinone dyes have better electrical properties to light than azo dyes, the order parameter of the dye alone tends to be inferior to azo dyes. Due to the problem, there is a problem that a higher addition concentration, that is, solubility is required than that of the azo dichroic dye.

In particular, the solubility of the anthraquinone dichroic dye and the dichroism of the anthraquinone-based dichroic dye are reduced for a host liquid crystal material mainly composed of a fluorine compound and a host liquid crystal material having a negative dielectric anisotropy widely used for active matrix driving. Therefore, it has been difficult to achieve both high dichroism required for realizing high contrast characteristics and high solubility in a host liquid crystal material.

Further, the anthraquinone dichroic dye has a narrower absorption width in the absorption spectrum than the azo dichroic dye,
Since the absorption peak is also steep, it has been difficult to achieve a smooth absorption spectrum with excellent color rendering in a composition comprising only an anthraquinone dye. Therefore, a liquid crystal composition containing a plurality of anthraquinone-based dichroic dyes is known, for example, from JP-A-2-173090, JP-A-2-178390, and the like, but has insufficient performance. Therefore, improvement was required.

The present invention provides a guest host having a hue such as black, brown or dark blue for the purpose of performing multicolor display such as multicolor or full color by using a monocolor display or a micro color filter with good visibility. It is an object of the present invention to provide a guest-host type liquid crystal composition having high contrast characteristics and high durability when using a liquid crystal composition, and particularly having excellent color rendering when having a black hue.

[0009]

SUMMARY OF THE INVENTION The present inventors have
As a result of intensive studies to solve the above problems in the guest-host liquid crystal composition, the guest-host type liquid crystal composition obtained in the combination of the specific two kinds of anthraquinone dichroic dyes has good contrast characteristics. The inventors have found that the present invention has excellent durability and color rendering, and have completed the present invention.

That is, the gist of the present invention is to provide a dichroic dye composition comprising the following general formula [I-1] and general formula [II]
And a dichroic dye composition comprising at least one dichroic dye represented by the formula: Anthraquinone dichroic dye represented by the following general formula [I-1]

[0011]

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Wherein R ¹ and R ² each independently represent a hydrogen atom or a halogen atom which may be substituted with a halogen atom.
It represents a 12 alkyl group, an alkoxy group having 1 to 12 carbon atoms which may be substituted with a halogen atom, an alkoxyalkyl group having 2 to 12 carbon atoms which may be substituted with a halogen atom, or a halogen atom. ) Anthraquinone dichroic dye represented by the following general formula [II]

[0013]

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Wherein R ³ and R ⁴ each independently represent a hydrogen atom or a halogen atom which may be substituted with a halogen atom.
It represents a 12 alkyl group, an alkoxy group having 1 to 12 carbon atoms which may be substituted by a halogen atom, an alkoxyalkyl group having 2 to 12 carbon atoms which may be substituted by a halogen atom, or a halogen atom. The second gist of the present invention is to provide a dichroic dye composition comprising the dichroic dyes represented by the general formulas [I-1], [II] and [I-2]. At least one each
A dichroic dye composition characterized in that it contains seeds.

[0015]

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Wherein R ⁵ and R ⁶ each independently represent a hydrogen atom or a halogen atom which may be substituted with a halogen atom.
It represents a 12 alkyl group, an alkoxy group having 1 to 12 carbon atoms which may be substituted with a halogen atom, an alkoxyalkyl group having 2 to 12 carbon atoms which may be substituted with a halogen atom, or a halogen atom. Further, another gist of the present invention is to provide a guest-host type liquid crystal composition using the dichroic dye composition and the host liquid crystal, and a liquid crystal using the guest-host type liquid crystal composition. Present in display elements.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The dichroic dye composition and the guest-host liquid crystal composition of the present invention have a hue such as black, dark blue, or brown, and the dyes used in the present invention are as described above. The combination of dichroic dyes produces an effect, and each dye is known. The dye represented by the general formula [I-1] is described in, for example,
The dye represented by the general formula [II] is described in, for example, JP-A-59-4650, and the dye represented by the general formula [I-2] is described in, for example, JP-A-62-101.
No. 658, etc., these anthraquinone dyes have insufficient order parameters when used alone.

Next, the dye used in the present invention will be described in detail. That is, the dichroic dye composition of the present invention comprises one or more dichroic dyes from the general formula [I-1] and one or more dichroic dyes from the general formula [II]. A composition. The dichroic dye composition of the present invention comprises at least one kind from the general formula [I-1], at least one kind from the general formula [II],
A dichroic dye composition comprising one or more dichroic dyes from the general formula [I-2].

The above general formula [I-1] used in the present invention
R ¹ and R ² in the dichroic dye represented by each independently represent a hydrogen atom; methyl, ethyl, n-propyl, iso-propyl, n-butyl, t-butyl, pentyl An alkyl group having 1 to 12 carbon atoms such as a group, hexyl group, heptyl group, octyl group or nonyl group; methoxy group, ethoxy group, n-propoxy group, iso-propoxy group, n-butoxy group, t-butoxy group, etc. An alkoxy group having 1 to 12 carbon atoms corresponding to the alkyl group; a methoxymethyl group, a methoxyethyl group, a methoxybutyl group,
An alkoxyalkyl group having 2 to 12 carbon atoms such as an ethoxymethyl group, an ethoxyethyl group or an ethoxybutyl group; a halogen atom such as a fluorine atom, a chlorine atom and a bromine atom; a difluoromethyl group, a trifluoroethyl group and a pentafluoropentyl group A halogen-substituted alkyl group in which a halogen atom such as a fluorine atom is substituted for an alkyl group having 1 to 12 carbon atoms; a halogen atom such as a fluorine atom in an alkoxy group having 1 to 12 carbon atoms such as a trifluoroethoxy group and a difluoroethoxy group Is a halogen-substituted alkoxyalkyl group; a halogen-substituted alkoxyalkyl group in which a halogen atom such as a fluorine atom is substituted for an alkoxyalkyl group having 1 to 12 carbon atoms, preferably a linear alkyl having 2 to 10 carbon atoms. And more preferably a linear alkyl group having 3 to 8 carbon atoms. A. As -Y ¹ -and -Y ^2- ,

[0020]

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[0021] R ³ and R ⁴ in the dichroic dye represented by the general formula [II] each independently represent a hydrogen atom; a methyl group, an ethyl group, an n-propyl group,
an alkyl group having 1 to 12 carbon atoms such as an isopropyl group, an n-butyl group, a t-butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group or a nonyl group; a methoxy group;
An ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, a t-butoxy group, an alkoxy group having 1 to 12 carbon atoms corresponding to the above alkyl group; a methoxymethyl group, a methoxyethyl group, a methoxybutyl group, An alkoxyalkyl group having 2 to 12 carbon atoms such as an ethoxymethyl group, an ethoxyethyl group or an ethoxybutyl group; a halogen atom such as a fluorine atom, a chlorine atom and a bromine atom; a difluoromethyl group, a trifluoroethyl group and a pentafluoropentyl group A halogen-substituted alkyl group in which a halogen atom such as a fluorine atom is substituted for an alkyl group having 1 to 12 carbon atoms;
A halogen-substituted alkoxy group in which a halogen atom such as a fluorine atom is substituted for an alkoxy group having 1 to 12 carbon atoms such as a trifluoroethoxy group or a difluoroethoxy group;
Halogen-substituted alkoxyalkyl groups in which a halogen atom such as a fluorine atom is substituted for an alkoxyalkyl group having 1 to 12 carbon atoms, preferably a linear alkyl group having 2 to 10 carbon atoms, and more preferably 3 to 12 carbon atoms. 8 linear alkyl groups, and -X- includes -NH-,
-S- can be mentioned, -Y ³ - and -Y ⁴ - as is
Each independently

[0022]

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[0023] R ⁵ and R ⁶ in the dichroic dye represented by formula [I-2] each independently represent a hydrogen atom; a methyl group, an ethyl group, an n-propyl group, an isopropyl group, and an n-butyl group. An alkyl group having 1 to 12 carbon atoms such as a group, t-butyl group, pentyl group, hexyl group, heptyl group, octyl group or nonyl group; methoxy group, ethoxy group, n-propoxy group, iso-propoxy group, n- An alkoxy group having 1 to 12 carbon atoms corresponding to the above alkyl group such as butoxy group, t-butoxy group; carbon number such as methoxymethyl group, methoxyethyl group, methoxybutyl group, ethoxymethyl group, ethoxyethyl group or ethoxybutyl group; 2 to 12 alkoxyalkyl groups; halogen atoms such as fluorine, chlorine, and bromine; difluoromethyl, trifluoroethyl, and pentaful A halogen-substituted alkyl group in which a halogen atom such as a fluorine atom is substituted for an alkyl group having 1 to 12 carbon atoms such as a lopentyl group; a fluorine atom or the like in an alkoxy group having 1 to 12 carbon atoms such as a trifluoroethoxy group and a difluoroethoxy group; A halogen-substituted alkoxy group in which a halogen atom is substituted; a halogen-substituted alkoxyalkyl group in which a halogen atom such as a fluorine atom is substituted for an alkoxyalkyl group having 1 to 12 carbon atoms, and preferably a straight-chain having 2 to 10 carbon atoms. include chain alkyl groups, more preferably include a linear alkyl group having 3 to 8 carbon atoms, -Y ⁵ - and -Y ⁶ -
as,

[0024]

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[0025] The dichroic dye composition of the present invention preferably contains at least one dye represented by the general formula [I-1], and in the dye represented by the general formula [II], -X- , —NH—, and —S—, each containing at least one dye. More preferably, each of the dyes represented by the general formulas [I-1] and [I-2] contains at least one dye, and in the dyes represented by the general formula [II], -X- , —NH—, and —S—, each containing at least one dye.

In the dichroic dye composition of the present invention, the weight ratio of the dichroic dye represented by the general formula [I-1] and the dichroic dye represented by the general formula [II] is determined as desired. Depending on the hue of the liquid crystal composition, dark blue, dark gray,
For brown, usually 25 to 75: 75 to 25, preferably 5
0 to 70: 50 to 30. The dichroic dye represented by the general formula [I-1], the dichroic dye represented by the general formula [I-2], and the dichroic dye represented by the general formula [II] in the dichroic dye composition of the present invention. The weight ratio of the dichroic dye varies depending on the hue of the target liquid crystal composition, but is usually 5 to 70:10 to 7 for dark blue, dark gray, brown and black.
0: 20-75, preferably 20-50: 20-50: 3
0 to 50.

The dichroic dye composition of the present invention may contain other dichroic dyes within a range not to impair the effects of the present invention. Specific examples of the dichroic dyes used in the present invention include the dyes described in Table 1 below.

[0028]

[Table 1]

[0029]

[Table 2]

The host liquid crystal material used in the present invention includes:
A fluorine-based liquid crystal material containing a liquid crystal compound having a positive dielectric anisotropy represented by the following structural formula [III] as a main component, or a dielectric anisotropic material represented by the structural formulas [IV] and [V] A fluorine-based and cyano-based liquid crystal material mainly containing a liquid crystal compound having a negative property, or a cyano-based liquid crystal material mainly containing a liquid crystal compound represented by the structural formulas [VI] and [VII].

[0031]

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(In each formula, ring A represents a cyclohexane ring, a benzene ring, a dioxane ring, or a pyrimidine ring;
Represents an integer of 1 to 3. -Z- is a single bond, -COO-,-
CH ₂ CH ₂ —, —CH ＝ CH— or —C≡C— is shown. R ⁷ and R ⁹ in the general formula [III] each independently represent a hydrogen atom; a halogen atom such as a fluorine group or a chlorine group; R ⁸ represents a halogen atom such as a fluorine group or a chlorine group; A substituted alkyl group, a substituted alkoxy group or a substituted alkenyl group having 1 to 7 carbon atoms having a halogen atom as a substituent; a substituted cyclohexyl group or a substituted phenyl group having these substituted alkyl group, substituted alkoxy group or substituted alkenyl group as a substituent Represents

R ¹² and R ¹³ in the general formula [IV] each independently represent a cyano group; a halogen atom such as a fluorine group and a chlorine group. R ¹⁰ in the general formula [III], R ¹¹ and R ^{14 in} the general formula [IV], R ¹⁵ and R ¹⁶ in the general formula [V],
R ¹⁷ in the general formula [VI] and R ¹⁸ in the general formula [VII] each independently represent an alkyl group having 1 to 10 carbon atoms;
Represents an alkoxy group having 1 to 10 carbon atoms, an alkoxyalkyl group having 2 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms. )

Of these, R in the general formula [III]
^A fluorine-based liquid crystal in which ⁸ is a fluorine atom or a substituent of fluorine and a fluorine-based liquid crystal in which R ¹² and R ¹³ in the general formula [IV] are fluorine atoms are preferably used in view of charge retention characteristics in active driving. The guest-host type liquid crystal composition of the present invention includes various ultraviolet absorbers and antioxidants and an optically active alkyl group as a terminal substituent of a steroid liquid crystal such as cholesteric nanoate and a liquid crystal compound as a chiral dopant. A chiral nematic liquid crystal into which an optically active alkoxy group or the like has been introduced may be added usually up to about 0.1 to 10% by weight of the guest-host type liquid crystal composition. Further, other dichroic dyes may be contained as long as the effects of the present invention are not impaired. The concentration of the dichroic dye in the guest-host type liquid crystal composition of the present invention is usually 0.1 to 15% by weight based on the host liquid crystal material.
Preferably it is 0.5 to 5% by weight.

The guest-host type liquid crystal composition of the present invention can be easily obtained by mixing and dissolving the liquid crystal composition with a dichroic dye and various additives by an operation such as shaking. The guest-host type liquid crystal composition prepared in this manner can be used in a TN mode or STN mode, and further edited by the 142nd Committee of the Japan Society for the Promotion of Science; “Liquid Crystal Device Handbook”
Nippon Kogyo Shimbun (1989), pages 315 to 329 and pages 367 to 370, etc. At least one of which is processed so as to obtain an electro-optical effect such as various guest host modes such as a Heilmeier type guest host is transparent. The liquid crystal device handbook, Nippon Kogyo Shimbun (1989), p. 387-434, p. 387-434, etc., and various active devices such as thin film transistors and MIM. Various display elements can be obtained by combining the active driving methods. The liquid crystal composition of the present invention thus obtained has a high order parameter and a high coloring density, and thus can achieve a high contrast ratio when a liquid crystal display is formed, and is suitable for active driving.

[0036]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to the following examples unless it exceeds the gist. [Example 1] A dichroic dye having the following structural formula shown in Table 1 was traded for trade name MLC-2039 (manufactured by E. MERCK).
Was mixed and dissolved in 1 g of a liquid crystal mixture having a negative dielectric anisotropy and containing a fluorine-based compound as a main component, which was commercially available as a liquid crystal composition-I. [I-1-2] 15.5 mg [II-2] 3.3 mg [II-6] 13.4 mg [I-2-2] 8.8 mg

This liquid crystal composition-I was applied to a cell made of a glass plate with a transparent electrode, which was coated with a polyimide resin, cured and rubbed, and then subjected to a homogeneous alignment treatment. Injection was performed to produce a guest-host type liquid crystal element-I-1. In this element,
Polarized light parallel to the rubbing direction and polarized light perpendicular to the rubbing direction were irradiated, and transmitted light spectra (A parallel and A vertical) were measured. Using these values, the order parameter was calculated by the following equation.

Order parameter (S value) = (A-parallel-A-vertical) / (A-parallel + 2 × A-vertical) The order parameter value at each wavelength is as shown in Table 2 below. The value was 0.79, indicating good contrast characteristics. Further, as shown in the relative absorption spectrum chart of A parallel and A vertical shown in FIG. 1, the present composition showed a smooth spectral characteristic suitable for a reflection type liquid crystal display device.

[0039]

[Table 3]

Further, the liquid crystal composition I was applied to a cell made of a glass plate with a transparent electrode which had been coated with a polyimide resin and cured and homeotropically aligned, thereby producing a guest-host type liquid crystal element I-2. . The voltage holding ratio of this device was measured under the following conditions. As a result, it was found to be 98.2%, indicating a driving characteristic suitable for active driving.

(Measurement conditions of voltage holding ratio) Frame frequency: 33 Hz Applied voltage: 5 V ON time: 60 μsec Measurement temperature: 25 ° C.

[Example 2] Trade name MLC-2039
1 g of a liquid crystal mixture having a negative dielectric anisotropy and containing a fluorine-based compound as a main component, which is commercially available as (E. MERCK)
Was mixed with and dissolved in the following dichroic dye to prepare a liquid crystal composition-II. [I-1-2] 25.2 mg [II-2] 5.4 mg [II-7] 24.0 mg [I-2-5] 14.7 mg

This liquid crystal composition-II was injected into a homogeneous alignment cell in the same manner as in Example 1 to obtain a liquid crystal display device-II-1. The transmitted light spectrum (parallel A and vertical A) of this liquid crystal display device-II was measured in the same manner as in Example 1. The order parameter was calculated using these values. Table 3 shows the order parameters at each wavelength. FIG. 2 shows relative absorption spectrum charts of A parallel and A perpendicular.

[0044]

[Table 4]

Further, the liquid crystal composition-II was injected into the homeotropic alignment cell in the same manner as in Example 1 to obtain a liquid crystal display device-II-2. The voltage holding ratio of this device was measured under the same conditions as in Example 1. As a result, good driving characteristics of 98.7% were exhibited.

[Embodiment 3] Product name ZLI-4792
1 g of a liquid crystal mixture containing a fluorine compound as a main component and having a positive dielectric anisotropy, which is commercially available as (E. MERCK)
The following dichroic dye is mixed and dissolved to give a liquid crystal composition-III
Was prepared. [I-1-5] 24.9 mg [II-3] 6.6 mg [II-6] 25.7 mg [I-2-3] 14.7 mg

This liquid crystal composition-III was injected into a cell in the same manner as in Example 1 to produce a liquid crystal display element-III. The transmitted light spectrum of this liquid crystal display element-III (A
(Parallel and A vertical) were measured in the same manner as in Example 1. The order parameter was calculated using these values. Table 4 shows order parameters at each wavelength. FIG. 3 shows relative absorption spectrum charts of A parallel and A perpendicular.

[0048]

[Table 5]

Further, the voltage holding ratio of this liquid crystal element-III was measured under the following conditions, and as a result, a good driving characteristic of 98.1% was exhibited. (Voltage holding ratio measurement conditions) Frame frequency: 33 Hz Applied voltage: 5 V ON time: 60 μsec Measurement temperature: 70 ° C.

[Embodiment 4] Product name ZLI-4792
A liquid crystal composition-IV was prepared by mixing and dissolving the following dichroic dye in 1 g of a liquid crystal mixture containing a fluorine-based compound as a main component and commercially available as (E. MERCK). [I-1-2] 15.7 mg [II-3] 3.7 mg [II-7] 15.7 mg [I-2-1] 7.4 mg

This liquid crystal composition-IV was injected into a cell in the same manner as in Example 1 to produce a liquid crystal display element-IV. The transmitted light spectrum (parallel A and vertical A) of this liquid crystal display device-IV was measured in the same manner as in Example 1. The order parameter was calculated using these values. Table-5 shows the order parameters at each wavelength. FIG. 4 shows relative absorption spectrum charts of A parallel and A perpendicular.

[0052]

[Table 6]

Further, the voltage holding ratio of this liquid crystal element-IV was measured under the same conditions as in Example 3, and as a result, a good driving characteristic of 98.5% was exhibited. [Comparative Example 1] described in JP-A-2-173090
Dye represented by the following structural formula

[0054]

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The product name is ZLI-1565 (E.MERC)
A liquid crystal composition mixed and dissolved in 100 g of a liquid crystal mixture containing a phenylcyclohexane-based compound as a main component and commercially available as a liquid crystal composition (manufactured by K Company K) has an order parameter value of 0.74 measured in the same manner as in the above-mentioned Example. (580n
m), 0.72 (540 nm), 0.70 (468 n
m), and sufficient contrast characteristics could not be obtained as compared with the liquid crystal composition of the present invention. [Comparative Example 2] described in JP-A-2-178390
Dye represented by the following structural formula

[0056]

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The product name is ZLI-1565 (E.MERC)
A liquid crystal composition mixed and dissolved in 100 g of a liquid crystal mixture containing a phenylcyclohexane-based compound as a main component and commercially available as a liquid crystal composition (manufactured by K Company K) has an order parameter value of 0.74 measured in the same manner as in the above-mentioned Example. (575n
m), 0.72 (539 nm), 0.70 (467 n
m), and sufficient contrast characteristics could not be obtained as compared with the liquid crystal composition of the present invention.

[0058]

According to the present invention, a guest-host type liquid crystal composition containing an anthraquinone-based dichroic dye having a high dichroic or order parameter can be obtained, and a guest-host type liquid crystal device having excellent contrast characteristics and driving characteristics can be obtained. Can be realized.

[Brief description of the drawings]

FIG. 1 is a relative absorption spectrum chart of A parallel and A vertical in Example 1.

FIG. 2 is a relative absorption spectrum chart of A parallel and A vertical in Example 2.

FIG. 3 is a relative absorption spectrum chart of A parallel and A vertical in Example 3.

FIG. 4 is a relative absorption spectrum chart of A parallel and A vertical in Example 4. In FIG. 1 to FIG.
The solid line indicates the relative absorption spectrum parallel to A, and the dotted line indicates the relative absorption spectrum perpendicular to A.

FIG. 5 is a schematic sectional view of a reflection type liquid crystal display device in a phase transition mode as an example of a liquid crystal display device according to the present invention.

[Explanation of symbols]

1. Incident light 2. Glass substrate 3. Transparent electrode 4. Alignment film Dichroic dye 6. Liquid crystal composition 7. Reflective layer 8. reflected light

Claims (6)

[Claims] 1. A compound represented by the following general formula [I-1] and general formula [I
A dichroic dye composition comprising at least one anthraquinone dichroic dye represented by I). Embedded image R ¹ and R ² are each independently a hydrogen atom, an alkyl group having 1 to 12 carbon atoms which may be substituted with a halogen atom, or an alkoxy group having 1 to 12 carbon atoms which may be substituted with a halogen atom. Represents an alkoxyalkyl group having 2 to 12 carbon atoms which may be substituted with a halogen atom or a halogen atom. ) R ³ and R ⁴ are each independently a hydrogen atom, an alkyl group having 1 to 12 carbon atoms which may be substituted by a halogen atom, or an alkoxy group having 1 to 12 carbon atoms which may be substituted by a halogen atom. Represents an alkoxyalkyl group having 2 to 12 carbon atoms which may be substituted with a halogen atom or a halogen atom. ) 2. A dichroic dye comprising at least one anthraquinone dichroic dye represented by the general formulas [I-1], [II] and [I-2]. Coloring dye composition. Embedded image R ⁵ and R ⁶ are each independently a hydrogen atom, an alkyl group having 1 to 12 carbon atoms which may be substituted by a halogen atom, or an alkoxy group having 1 to 12 carbon atoms which may be substituted by a halogen atom. Represents an alkoxyalkyl group having 2 to 12 carbon atoms which may be substituted with a halogen atom or a halogen atom. ) 3. A guest-host type liquid crystal composition comprising the dichroic dye composition according to claim 1 and a host liquid crystal. 4. The guest-host type liquid crystal composition according to claim 3, wherein the host liquid crystal is a fluorine-based liquid crystal material containing a fluorine-based liquid crystal compound as a main component. 5. The guest-host type liquid crystal composition according to claim 3, wherein the host liquid crystal is a fluorine-based liquid crystal material containing a fluorine-based liquid crystal compound having a negative dielectric anisotropy as a main component. Guest-host type liquid crystal composition. 6. A liquid crystal display device characterized in that at least one of the guest-host type liquid crystal compositions according to claim 3, 4 or 5 is sandwiched between transparent substrates with electrodes.