JP2015055685A - Optical element and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical element in which a threshold value of light intensity in which anisotropic molecules are oriented is lowered, and a manufacturing method thereof.SOLUTION: An optical element is prepared such that onto a light responsive composition 15 containing a light responsive substance 13 having a threshold value of light intensity to respond and anisotropic molecules, light having light intensity of a threshold value or more is irradiated, so that the light responsive composition is oriented.

Description

 The present invention relates to an optical element and a method for manufacturing the same.

 Liquid crystals are highly functional materials that have both fluidity and large refractive index anisotropy, and have characteristics that exhibit self-organization ability and cooperative effects not found in other materials. Furthermore, the liquid crystal has a feature that the molecular arrangement can be freely controlled by the substrate surface treatment or an external field. For example, liquid crystal molecules can be aligned in parallel or perpendicular to the substrate by forming an alignment film typified by polyimide or a silane coupling agent on the surface of the substrate. In addition, when an electric field is used in the external field, the liquid crystal molecules aligned in parallel to the substrate change in orientation perpendicular to the substrate by applying a voltage. Is possible. This alignment control method is widely used as the operating principle of the current liquid crystal display.

 In recent years, among liquid crystal alignment techniques, a method using light is attracting attention as a new technique for replacing a conventional alignment film and electric field application. Since light is clean energy, has a quick response, and can be remotely operated without providing complicated wirings, research on the alignment of liquid crystals using light has been actively conducted.

 One method for controlling the alignment of the liquid crystal with light includes a method of doping the liquid crystal with a dye that strongly interacts with light. As a method for controlling the alignment of the liquid crystal, a photochemical control method based on photoisomerization of azobenzene (Weigert effect, hereinafter also referred to as “photochemical process”) is widely known. In addition, a photophysical control method (Janossy effect, hereinafter also referred to as “photophysical process”) based on the interaction between excitation polarization of a dye such as anthraquinone and a photoelectric field has been studied (for example, see Non-Patent Document 1). ).

 The photochemical process is a method using a linear optical effect that shows a response even to extremely weak light, while the photophysical process is a method using a nonlinear optical effect. It is very different from photophysical process. However, since the conventionally known photophysical process requires high light intensity, it has not been actively studied.

Janossy I. et al. Mol. Cryst. Liq. Cryst., 1990, 179, 1.

The photophysical process has a problem in that the threshold of light intensity at which the liquid crystal responds (aligns) is extremely high.
If the orientation change of the liquid crystal can be induced at a lower light intensity by the photophysical process using the nonlinear optical effect, it is possible to manufacture a small device based on a new principle.

 This invention is made | formed in view of the said situation, Comprising: It aims at providing the optical element which made the threshold value of the light intensity which an anisotropic molecule orientates low, and its manufacturing method.

 The present inventors use a photoresponsive composition containing a photoresponsive substance having a threshold value in response light intensity and an anisotropic molecule, thereby setting the threshold value of the light intensity at which the anisotropic molecule is oriented. The inventors have found that it can be lowered, and have completed the present invention.

 That is, the present invention provides a photoresponsive composition containing a photoresponsive substance having a threshold value in response light intensity and an anisotropic molecule by irradiating light having a light intensity equal to or greater than the threshold value. An optical element in which a responsive composition is oriented is provided.

 Further, the present invention irradiates a photoresponsive composition containing a photoresponsive substance having a threshold value in response light intensity and an anisotropic molecule with light having a light intensity equal to or higher than the threshold value. A method for producing an optical element for orienting a photoresponsive composition is provided.

 According to the present invention, by using a photoresponsive composition containing a photoresponsive substance having a threshold value in response light intensity and an anisotropic molecule, the threshold value of the light intensity at which the anisotropic molecule is aligned is set. Can be lowered.

It is a schematic sectional drawing which shows a liquid crystal display element as one Embodiment of the optical element of this invention. It is a graph which shows the relationship between the intensity | strength (light intensity) of a laser beam, and the number of interference fringes. It is a graph which shows the relationship between content of A4CB and the light intensity (threshold of light intensity) where the number of interference fringes increases rapidly. It is a graph which shows the relationship between content of A4CB and the maximum number of interference fringes.

Embodiments of the optical element and the manufacturing method thereof according to the present invention will be described.
Note that this embodiment is specifically described for better understanding of the gist of the invention, and does not limit the present invention unless otherwise specified.

[Optical element]
The optical element of the present invention emits light by irradiating a photoresponsive composition containing a photoresponsive substance having a threshold value in response light intensity and an anisotropic molecule with light having a light intensity equal to or greater than the threshold value. The responsive composition is oriented.
The optical element of the present invention expresses an optical function by controlling orienting anisotropic molecules with light so that the refractive index of the photoresponsive composition is modulated or distributed spatially and regionally. It is. The optical element of the present invention can be applied to optical elements (for example, lenses, prisms, mirrors, filters, etc.) using a refractive index distribution without any particular limitation, and also includes liquid crystal display elements, hologram elements, retardation films, etc. Can be used as a phase difference element, a 3D printer element, and the like.

Here, the liquid crystal display element 10 shown in FIG. 1 is illustrated as an optical element of the present invention.
The liquid crystal display element 10 is roughly composed of two substrates 11 and 12 and a photoresponsive composition 15 containing a photoresponsive material 13 and an anisotropic molecule 14 enclosed between the substrates. ing.
When the optical element of the present invention is the liquid crystal display element 10, as the substrates 11 and 12, for example, glass substrates are used.
In addition, an alignment film 16 that has been subjected to a vertical alignment treatment with a silane coupling agent is provided on a surface 11 a of the one substrate 11 facing the other substrate 12. Similarly, an alignment film 17 that has been subjected to a vertical alignment treatment with a silane coupling agent is provided on the surface 12a of the other substrate 12 facing the one substrate 11.
The optical element of the present invention includes a substrate and a photoresponsive composition layer (a layer made of a photoresponsive composition) containing a photoresponsive substance and anisotropic molecules formed on the substrate. You may be comprised by the optical element (namely, element | device with only one board | substrate) comprised roughly. Such an optical element can be obtained by applying a coating liquid containing a photoresponsive substance and anisotropic molecules on a substrate.

As the photoresponsive substance, a compound having a threshold value for the light intensity to be used is used. Specifically, the photoresponsive substance is not particularly limited as long as it has a molecular structure having anisotropy in light absorption. As the photoresponsive substance, a substance that does not cause a photochemical reaction or has a small influence on the orientation of the anisotropic substance even when the photochemical reaction is caused is preferable. For example, a visible light region or a visible light region A compound having a threshold value in the intensity of the light that absorbs the light and responds to light emitted from any region outside is used.
In the present invention, the photoresponsive substance responds when irradiated with light, and the photoresponsive substance is oriented when irradiated with light. More specifically, the photoresponsive substance is oriented such that the long axis direction of the photoresponsive substance is parallel to the vibration direction of light (electric field vector of polarized light).

 As such a photoresponsive substance, for example, a dichroic dye is used as a substance that responds to light in the visible light region. The dichroic dye is not particularly limited, and anthraquinone, merocyanine, styryl, azomethine, quinone, quinophthalone, perylene, indigo, tetrazine, stilbene, benzidine, etc. Can be mentioned. Oligothiophene is also preferably used.

 As the photoresponsive substance, for example, the following general formula (I-1)

Wherein R ¹ and R ² are each independently a hydrogen atom, an alkyl group having 1 to 14 carbon atoms, an alkenyl group having 2 to 14 carbon atoms, an alkynyl group having 2 to 14 carbon atoms, carbon Represents an alkoxy group having 1 to 14 atoms, a cyano group (—CN), a nitro group (—NO ₂ ), and one or two or more CH ₂ groups in the alkyl group are not directly adjacent to each other. In addition, it may be substituted with -O-, -CO-, -OCO-, or -COO-, and one or more hydrogen atoms in the alkyl group, alkenyl group, alkynyl group, alkoxy group are (It may be optionally substituted with a halogen atom, and n represents 1 to 8.)
And an oligothiophene compound represented by the formula:
R ¹ and R ² are each independently an alkyl group having 1 to 10 carbon atoms (—C _n H _{2n + 1} ), —OC _n H _{2n + 1} , —N (C _n H _{2n + 1} ) ₂ , —COOC _n H _{2n + 1} , A cyano group (—CN) and a nitro group (—NO ₂ ) are preferable, and an alkyl group having 2 to 5 carbon atoms (—C _n H _{2n + 1} ), —OC _n H _{2n + 1} , —N (C _n H) _{2n + 1} ) ₂ and -COOC _n H _{2n + 1} are more preferable.
n is preferably 1 to 5, and more preferably 1 to 3.
The general formula (I-1) is represented by the following general formula (I-2)

(Wherein, ^{R 1} and ^{R 2} have the same meanings as ^{R 1} and ^{R 2} in the general formula (I-1).)
It is preferable that it is a compound represented by these.
As the compound represented by the general formula (I-2), specifically, as a compound having symmetry, the following formula (I-3)

A compound represented by the following general formula (I-4)

And compounds in which R ¹ and R ² represent —C ₄ H ₉ , —OC ₄ H ₉ , —N (C ₄ H ₉ ) ₂ , —COOC ₄ H ₉ , and —CN, respectively. It is done.
The compound represented by the general formula (I-2), as a compound having an asymmetric, ^{R 1} is _-C 4 _{H 9, or, -N (C 4 H 9)} 2, R 2 is - A compound representing CN or —NO ₂ is exemplified.
The general formula (I-1) is a compound represented by the following formula (I-5):

And a compound represented by the following formula (I-6):

And a non-colored compound represented by the formula:
As other oligothiophene compounds, the following general formula (I-7)

(Wherein, ^{R 1} and ^{R 2} represent the same meanings as ^{R 1} and ^{R 2} in the general formula (I-1), n represents 0 or 1.)
The compound represented by these is mentioned.
Examples of the compound represented by the general formula (I-7) include the following formula (I-8)

(In the formula, n represents 0 or 1.)
The compound represented by these is mentioned.
Moreover, as a photoresponsive substance, the following general formula (I-9)

(Wherein, ^{R 1} and ^{R 2} have the same meanings as ^{R 1} and ^{R 2} in the general formula (I-1).)
The compound represented by these is mentioned.
Examples of the compound represented by the general formula (I-9) include the following formula (I-10)

The compound represented by these is mentioned.
Moreover, as a photoresponsive substance, the following general formula (I-11)

(In the formula, A ¹ and A ² each independently represent a 1,4-phenylene group, a 2,5-thiophene group, or a naphthalene-2,6-diyl group, and R ′ and R ″ each represent Independently, —CH═CH— group and —C≡C— group are represented, and R ¹ and R ² represent the same meaning as R ¹ and R ^{2 in} formula (I-1), and n ₁ and n ₂ independently represents 0 to 8, and n ₃ and n ₄ each independently represents 0 or 1.)
The compound represented by these is mentioned.
n ₁ and _{n 2} is preferably 0-6, more preferably 0-4.
Specific examples of the compound represented by the general formula (I-11) include compounds represented by the following formulas (I-12) to (I-19).

（式中、Ｒ^１およびＲ^２は、前記一般式（Ｉ−１）のＲ^１およびＲ^２と同じものを表す。）

(Wherein, ^{R 1} and ^{R 2} represent the same as ^{R 1} and ^{R 2} in the general formula (I-1).)

（式中、Ｒ^１およびＲ^２は、前記一般式（Ｉ−１）のＲ^１およびＲ^２と同じ意味を表す。）

(Wherein, ^{R 1} and ^{R 2} have the same meanings as ^{R 1} and ^{R 2} in the general formula (I-1).)

（式中、Ｒ^１およびＲ^２は、前記一般式（Ｉ−１）のＲ^１およびＲ^２と同じ意味を表す。）

(Wherein, ^{R 1} and ^{R 2} have the same meanings as ^{R 1} and ^{R 2} in the general formula (I-1).)

（式中、Ｒ^１およびＲ^２は、前記一般式（Ｉ−１）のＲ^１およびＲ^２と同じ意味を表す。）

(Wherein, ^{R 1} and ^{R 2} have the same meanings as ^{R 1} and ^{R 2} in the general formula (I-1).)

（式中、Ｒ^１およびＲ^２は、前記一般式（Ｉ−１）のＲ^１およびＲ^２と同じ意味を表す。）

(Wherein, ^{R 1} and ^{R 2} have the same meanings as ^{R 1} and ^{R 2} in the general formula (I-1).)

（式中、Ｒ^１およびＲ^２は、前記一般式（Ｉ−１）のＲ^１およびＲ^２と同じ意味を表す。）

(Wherein, ^{R 1} and ^{R 2} have the same meanings as ^{R 1} and ^{R 2} in the general formula (I-1).)

（式中、Ｒ^１およびＲ^２は、前記一般式（Ｉ−１）のＲ^１およびＲ^２と同じ意味を表す。）

(Wherein, ^{R 1} and ^{R 2} have the same meanings as ^{R 1} and ^{R 2} in the general formula (I-1).)

（式中、Ｒ^１およびＲ^２は、前記一般式（Ｉ−１）のＲ^１およびＲ^２と同じ意味を表す。）

(Wherein, ^{R 1} and ^{R 2} have the same meanings as ^{R 1} and ^{R 2} in the general formula (I-1).)

 Moreover, as a photoresponsive substance, the following general formula (I-20)

Wherein R ³ and R ⁴ are each independently a hydrogen atom, an alkyl group having 1 to 14 carbon atoms, an alkenyl group having 2 to 14 carbon atoms, an alkynyl group having 2 to 14 carbon atoms, carbon Represents an alkoxy group having 1 to 14 atoms, a cyano group (—CN), a nitro group (—NO ₂ ), and one or two or more CH ₂ groups in the alkyl group are not directly adjacent to each other. In addition, it may be substituted with -O-, -CO-, -OCO-, or -COO-, and one or more hydrogen atoms in the alkyl group, alkenyl group, alkynyl group, alkoxy group are Optionally substituted with a halogen atom,
B ¹ and B ² are each independently a hydrogen atom, an alkyl group having 1 to 14 carbon atoms, an alkenyl group having 2 to 14 carbon atoms, an alkynyl group having 2 to 14 carbon atoms, or 1 to 1 carbon atom. 14 alkoxy groups, a cyano group (—CN), a nitro group (—NO ₂ ), an optionally substituted phenyl group (one or more —C═ present in this group is Which may be substituted), a naphthyl group which may have a substituent, a cyclohexyl group which may have a substituent (one or more —C— present in this group is —O—). Or may be substituted with -S-), and any one of the following groups (a), (b), or (c), and one or more CH ₂ in the alkyl group: The group is -O-, -CO-, -OCO-, or COO- may be substituted with the alkyl group, an alkenyl group, an alkynyl group, one or more hydrogen atoms in the alkoxy group may be optionally substituted halogen atom. )

（式中、Ｒ^５は、水素原子、炭素原子数１〜１４のアルキル基、炭素原子数２〜１４のアルケニル基、炭素原子数２〜１４のアルキニル基、炭素原子数１〜１４のアルコキシ基、シアノ基（−ＣＮ）、ニトロ基（−ＮＯ_２）を表し、前記アルキル基中の１つまたは２つ以上のＣＨ_２基は、酸素原子が直接隣接しないように、−Ｏ−、−ＣＯ−、−ＯＣＯ−、または−ＣＯＯ−で置換されていてもよく、前記アルキル基、アルケニル基、アルキニル基、アルコキシ基中の１つまたは２つ以上の水素原子は任意にハロゲン原子に置換されていてもよい。）

(In the formula, R ⁵ represents a hydrogen atom, an alkyl group having 1 to 14 carbon atoms, an alkenyl group having 2 to 14 carbon atoms, an alkynyl group having 2 to 14 carbon atoms, or an alkoxy group having 1 to 14 carbon atoms. , A cyano group (—CN), a nitro group (—NO ₂ ), and one or more CH ₂ groups in the alkyl group are —O—, —CO, so that oxygen atoms are not directly adjacent to each other. -, -OCO-, or -COO- may be substituted, and one or more hydrogen atoms in the alkyl group, alkenyl group, alkynyl group, and alkoxy group are optionally substituted with a halogen atom. May be.)

The coumarin type compound represented by these is mentioned.
When R ³ and R ⁴ represent an alkyl group, an alkyl group having 1 to 10 carbon atoms is preferable, an alkyl group having 1 to 5 carbon atoms is more preferable, and when B ¹ and B ² represent an alkyl group, carbon An alkyl group having 1 to 10 atoms is preferable, and an alkyl group having 1 to 5 carbon atoms is more preferable.
Examples of the compound represented by the general formula (I-20) include compounds represented by the following formulas (I-22) to (I-24).

（式中、Ｒ^３およびＲ^４は、前記一般式（Ｉ−２０）のＲ^３およびＲ^４と同じ意味を表す。）

(In the formula, R ³ and R ⁴ represent the same meaning as R ³ and R ^{4 in} formula (I-20)).

（式中、Ｒ^３およびＲ^４は、前記一般式（Ｉ−２０）のＲ^３およびＲ^４と同じ意味を表す。）

(In the formula, R ³ and R ⁴ represent the same meaning as R ³ and R ^{4 in} formula (I-20)).

（式中、Ｒ^３およびＲ^４は、前記一般式（Ｉ−２０）のＲ^３およびＲ^４と同じ意味を表す。）

(In the formula, R ³ and R ⁴ represent the same meaning as R ³ and R ^{4 in} formula (I-20)).

 As other coumarin compounds, the following general formula (I-25)

(Wherein, ^{B 1} and ^{B 2} have the same meanings as ^{B 1} and ^{B 2} in the general formula (I-20).)
The compound represented by these is mentioned.
When B ¹ and B ² represent an alkyl group, an alkyl group having 1 to 10 carbon atoms is preferable, and an alkyl group having 1 to 5 carbon atoms is more preferable.
Examples of the compound represented by the general formula (I-25) include compounds represented by the following formulas (I-26) to (I-30).

 Moreover, as a photoresponsive substance, the following general formula (I-31)

(Wherein R ⁶ and R ⁷ are each independently a hydrogen atom, an alkyl group having 1 to 14 carbon atoms, an alkenyl group having 2 to 14 carbon atoms, an alkynyl group having 2 to 14 carbon atoms, carbon, Represents an alkoxy group having 1 to 14 atoms, a cyano group (—CN), a nitro group (—NO ₂ ), and one or two or more CH ₂ groups in the alkyl group are not directly adjacent to each other. In addition, it may be substituted with -O-, -CO-, -OCO-, or -COO-, and one or more hydrogen atoms in the alkyl group, alkenyl group, alkynyl group, alkoxy group are Optionally substituted with a halogen atom,
B ³ is a hydrogen atom, an alkyl group having 1 to 14 carbon atoms, an alkenyl group having 2 to 14 carbon atoms, an alkynyl group having 2 to 14 carbon atoms, an alkoxy group having 1 to 14 carbon atoms, a cyano group (- CN), a nitro group (—NO ₂ ), an optionally substituted phenyl group (one or more —C═ present in this group may be substituted with —N═), A naphthyl group which may have a substituent, a cyclohexyl group which may have a substituent (one or more —C— present in this group is substituted with —O— or —S—). And one or more CH ₂ groups in the alkyl group may be —O—, —CO—, —OCO—, or —COO— so that the oxygen atoms are not directly adjacent. The alkyl group, alkenyl group, alkynyl group, One or more hydrogen atoms in the xy group may be optionally substituted with a halogen atom. )
The compound represented by these is mentioned.
When R ⁶ , R ⁷ and B ³ each independently represent an alkyl group, an alkyl group having 1 to 10 carbon atoms is preferable, and an alkyl group having 1 to 5 carbon atoms is more preferable. Moreover, when R < ⁶ >, R < ⁷ > and B < ³ > represent an alkenyl group each independently, a C2-C10 alkenyl group is preferable and a C2-C5 alkenyl group is more preferable. B ³ is preferably a phenyl group which may have a substituent. Examples of the substituent include an alkyl group having 1 to 14 carbon atoms, an alkenyl group having 2 to 14 carbon atoms, and 1 carbon atom. -14 alkoxy groups are preferable, and alkyl groups having 1 to 10 carbon atoms, alkenyl groups having 2 to 10 carbon atoms, and alkoxy groups having 1 to 10 carbon atoms are more preferable.
Examples of the compound represented by the general formula (I-31) include the following formula (I-32)

(In the formula, R ⁶ represents the same meaning as R ^{6 in the} general formula (I-31).)
A compound represented by formula (I-33):

(Wherein R ⁸ and R ⁹ are each independently a hydrogen atom, an alkyl group having 1 to 14 carbon atoms, an alkenyl group having 2 to 14 carbon atoms, an alkynyl group having 2 to 14 carbon atoms, Represents an alkoxy group having 1 to 14 carbon atoms, a cyano group (—CN), a nitro group (—NO ₂ ), and one or two or more CH ₂ groups in the alkyl group are not directly adjacent to each other with an oxygen atom. As described above, one or two or more hydrogen atoms in the alkyl group, alkenyl group, alkynyl group or alkoxy group, which may be substituted with -O-, -CO-, -OCO-, or -COO- May be optionally substituted with a halogen atom.)
The compound represented by these is mentioned.
Moreover, as a photoresponsive substance, the following general formula (I-34)

(In the formula, R ^{10 to} R ¹³ are each independently a hydrogen atom, an alkyl group having 1 to 14 carbon atoms, an alkenyl group having 2 to 14 carbon atoms, an alkynyl group having 2 to 14 carbon atoms, carbon, Represents an alkoxy group having 1 to 14 atoms, a cyano group (—CN), a nitro group (—NO ₂ ), and one or two or more CH ₂ groups in the alkyl group are not directly adjacent to each other. In addition, it may be substituted with -O-, -CO-, -OCO-, or -COO-, and one or more hydrogen atoms in the alkyl group, alkenyl group, alkynyl group, alkoxy group are It may be optionally substituted with a halogen atom.)
The compound represented by these is mentioned.
R ^{10 to} R ¹³ each independently preferably represent a hydrogen atom, an alkyl group having 1 to 10 carbon atoms in which a CH ₂ group in the alkyl group is substituted with —COO— or —OCO—, It is more preferable that the CH ₂ group in the hydrogen atom or the alkyl group represents a C 1-5 alkyl group substituted with —COO— or —OCO—.
Examples of the compound represented by the general formula (I-34) include the following formula (I-35)

(In the formula, R ¹⁴ and R ¹⁵ each independently represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms.)
A compound represented by formula (I-36):

(In formula, R < ¹⁴ > -R < ¹⁷ > represents a hydrogen atom or a C1-C10 alkyl group each independently.)
The compound represented by these is mentioned.
Moreover, as a photoresponsive substance, the following general formula (I-37)

(In the formula, B ⁴ is a hydrogen atom, an alkyl group having 1 to 14 carbon atoms, an alkenyl group having 2 to 14 carbon atoms, an alkynyl group having 2 to 14 carbon atoms, or an alkoxy group having 1 to 14 carbon atoms. , A cyano group (—CN), a nitro group (—NO ₂ ), an optionally substituted phenyl group (one or more —C═ present in this group is substituted with —N═. A naphthyl group which may have a substituent, a cyclohexyl group which may have a substituent (one or more —C— present in this group is —O— or —S—). NR ¹⁸ R ¹⁹ (R ¹⁸ and R ¹⁹ are each independently a hydrogen atom, an alkyl group having 1 to 14 carbon atoms, an alkenyl group having 2 to 14 carbon atoms, C2-C14 alkynyl group, C1-C14 alkoxy Group, a cyano group (-CN), nitro group (-NO _2), one or more CH ₂ groups in the alkyl groups, so that oxygen atoms are not directly adjacent, -O -, - May be substituted with CO-, -OCO-, or -COO-, may be substituted with a 1,4-phenylene group, and one of the above-mentioned alkyl group, alkenyl group, alkynyl group, alkoxy group or And two or more hydrogen atoms may be optionally substituted with a halogen atom.)
The compound represented by these is mentioned.
R ¹⁸ and R ^{19 in} formula (I-37) are preferably an alkyl group having 1 to 14 carbon atoms, an alkenyl group having 2 to 14 carbon atoms which may have a substituent, or a phenyl group. .
Examples of the compound represented by the general formula (I-37) include the following formula (I-38)

(In the formula, R ¹⁸ and R ¹⁹ represent the same meaning as R ¹⁸ and R ^{19 in} formula (I-37)).
A compound represented by formula (I-39):

(In the formula, R ²⁰ represents a hydrogen atom or an alkyl group having 1 to 14 carbon atoms.)
A compound represented by formula (I-40):

(In the formula, R ²¹ represents a hydrogen atom or an alkyl group having 1 to 14 carbon atoms.)
The compound represented by these is mentioned.
Moreover, as a photoresponsive substance, the following general formula (I-41)

(Wherein, X ¹ and X ² each independently represent a hydrogen atom, a fluorine atom or a chlorine atom, and B ^{5 to} B ⁸ each independently represent a hydrogen atom or an alkyl having 1 to 14 carbon atoms) A group, an alkenyl group having 2 to 14 carbon atoms, an alkynyl group having 2 to 14 carbon atoms, an alkoxy group having 1 to 14 carbon atoms, a cyano group (—CN), a nitro group (—NO ₂ ), and a substituent. An optionally substituted phenyl group (one or more —C═ present in this group may be substituted with —N═), an optionally substituted naphthyl group, a substituent; A cyclohexyl group optionally having one or more -C- present in the group may be substituted with -O- or -S-, and one of the alkyl groups or two or more CH ₂ groups, as the oxygen atoms are not directly adjacent, -O , -CO-, -OCO-, or -COO-, and one or more hydrogen atoms in the alkyl group, alkenyl group, alkynyl group, and alkoxy group may be optionally substituted with a halogen atom. It may be substituted, and n ₆ and n ₇ each independently represent 1 to 14.)
The dioxazine type compound represented by these is mentioned.
B ^{5 to} B ⁸ each independently have an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a phenyl group which may have a substituent, or a substituent. The cyclohexyl group which may be sufficient is preferable, and as this substituent, a C1-C10 alkyl group and a C1-C10 alkoxy group are preferable.
Examples of the compound represented by the general formula (I-41) include the following formula (I-42)

A compound represented by formula (I-43):

The compound represented by these is mentioned.
Moreover, as a photoresponsive substance, the following general formula (I-44)

(In the formula, each of B ^{9 to} B ¹² is independently a hydrogen atom, a hydroxy group, an alkyl group having 1 to 14 carbon atoms, an alkenyl group having 2 to 14 carbon atoms, or an alkynyl group having 2 to 14 carbon atoms. Group, an alkoxy group having 1 to 14 carbon atoms, a cyano group (—CN), a nitro group (—NO ₂ ), an optionally substituted phenyl group (one or more — C = may be substituted with -N =), a naphthyl group which may have a substituent, a cyclohexyl group which may have a substituent (one or more present in this group). -C- may be substituted with -O- or -S-), NR ¹⁸ R ¹⁹ (R ¹⁸ and R ¹⁹ are each independently a hydrogen atom or an alkyl group having 1 to 14 carbon atoms. , An alkenyl group having 2 to 14 carbon atoms, and 2 to 14 carbon atoms Rukiniru group, an alkoxy group having 1 to 14 carbon atoms, a cyano group (-CN), nitro group (-NO _2), one or more CH ₂ groups in the alkyl group, an oxygen atom In order not to be directly adjacent to each other, it may be substituted with —O—, —CO—, —OCO—, or —COO—, and may be substituted with a 1,4-phenylene group. , An alkynyl group or an alkoxy group, one or more hydrogen atoms may be optionally substituted with a halogen atom)
R ^{22 to} R ²⁵ are each independently a hydrogen atom, an alkyl group having 1 to 14 carbon atoms, an alkenyl group having 2 to 14 carbon atoms, an alkynyl group having 2 to 14 carbon atoms, or 1 to 1 carbon atom. 14 represents an alkoxy group, a cyano group (—CN), a nitro group (—NO ₂ ), and one or more CH ₂ groups in the alkyl group are —O—so that oxygen atoms are not directly adjacent to each other. -, -CO-, -OCO-, or -COO- may be substituted, and one or more hydrogen atoms in the alkyl group, alkenyl group, alkynyl group, and alkoxy group are optionally halogen atoms. May be substituted. )
The anthraquinone type compound represented by these is mentioned.
Examples of the compound represented by the general formula (I-44) include the following formula (I-45)

A compound represented by formula (I-46):

A compound represented by formula (I-47):

The compound represented by these is mentioned.
As other anthraquinone compounds, the following general formula (I-48)

(In the formula, B ^{9 to} B ¹² each independently represent the same meaning as B ^{9 to} B ^{12 of the} general formula (I-44);
R ²² , R ²³ and R ²⁶ are each independently a hydrogen atom, an alkyl group having 1 to 14 carbon atoms, an alkenyl group having 2 to 14 carbon atoms, an alkynyl group having 2 to 14 carbon atoms, or a carbon atom. Represents an alkoxy group of formula 1 to 14, a cyano group (—CN), a nitro group (—NO ₂ ), and one or two or more CH ₂ groups in the alkyl group are not directly adjacent to each other. , -O-, -CO-, -OCO-, or -COO-, one or two or more hydrogen atoms in the alkyl group, alkenyl group, alkynyl group, and alkoxy group may be any May be substituted with a halogen atom. )
The compound represented by these is mentioned.
Examples of the compound represented by the general formula (I-48) include the following formula (I-49)

The compound represented by these is mentioned.
Furthermore, as a photoresponsive substance, the following formula (I-50)

Wherein R ²⁷ is a hydrogen atom, an alkyl group having 1 to 14 carbon atoms, an alkenyl group having 2 to 14 carbon atoms, an alkynyl group having 2 to 14 carbon atoms, or an alkoxy group having 1 to 14 carbon atoms. , A cyano group (—CN), a nitro group (—NO ₂ ), and one or more CH ₂ groups in the alkyl group are —O—, —CO, so that oxygen atoms are not directly adjacent to each other. -, -OCO-, or -COO- may be substituted, and one or more hydrogen atoms in the alkyl group, alkenyl group, alkynyl group, and alkoxy group are optionally substituted with a halogen atom. May be.)
A compound represented by formula (I-51):

(In the formula, R ^{28 to} R ³⁰ are each independently a hydrogen atom, an alkyl group having 1 to 14 carbon atoms, an alkenyl group having 2 to 14 carbon atoms, an alkynyl group having 2 to 14 carbon atoms, or carbon. Represents an alkoxy group having 1 to 14 atoms, a cyano group (—CN), a nitro group (—NO ₂ ), and one or two or more CH ₂ groups in the alkyl group are not directly adjacent to each other. In addition, it may be substituted with -O-, -CO-, -OCO-, or -COO-, and one or more hydrogen atoms in the alkyl group, alkenyl group, alkynyl group, alkoxy group are It may be optionally substituted with a halogen atom.)
A compound represented by formula (I-52):

A compound represented by formula (I-53):

A compound represented by formula (I-54):

(Wherein R ³¹ and R ³² are each independently a hydrogen atom, an alkyl group having 1 to 14 carbon atoms, an alkenyl group having 2 to 14 carbon atoms, an alkynyl group having 2 to 14 carbon atoms, carbon, Represents an alkoxy group having 1 to 14 atoms, a cyano group (—CN), a nitro group (—NO ₂ ), and one or two or more CH ₂ groups in the alkyl group are not directly adjacent to each other. In addition, it may be substituted with -O-, -CO-, -OCO-, or -COO-, and one or more hydrogen atoms in the alkyl group, alkenyl group, alkynyl group, alkoxy group are It may be optionally substituted with a halogen atom.)
A compound represented by formula (I-55):

Wherein Y ¹ and Y ² are each independently a hydrogen atom, a fluorine atom, an alkyl group having 1 to 14 carbon atoms, an alkenyl group having 2 to 14 carbon atoms, or an alkynyl group having 2 to 14 carbon atoms. Group, an alkoxy group having 1 to 14 carbon atoms, a cyano group (—CN), a nitro group (—NO ₂ ), and one or two or more CH ₂ groups in the alkyl group have a direct oxygen atom It may be substituted with —O—, —CO—, —OCO—, or —COO— so as not to be adjacent to each other, and one or more of the alkyl group, alkenyl group, alkynyl group, and alkoxy group may be substituted. (The hydrogen atom may be optionally substituted with a halogen atom.)
A compound represented by formula (I-56):

Wherein R ³³ and R ³⁴ are each independently a hydrogen atom, an alkyl group having 1 to 14 carbon atoms, an alkenyl group having 2 to 14 carbon atoms, an alkynyl group having 2 to 14 carbon atoms, carbon Represents an alkoxy group having 1 to 14 atoms, a cyano group (—CN), a nitro group (—NO ₂ ), and one or two or more CH ₂ groups in the alkyl group are not directly adjacent to each other. In addition, it may be substituted with -O-, -CO-, -OCO-, or -COO-, and one or more hydrogen atoms in the alkyl group, alkenyl group, alkynyl group, alkoxy group are It may be optionally substituted with a halogen atom.)
A compound represented by formula (I-57):

(Wherein R ^{35 to} R ³⁸ are each independently a hydrogen atom, an alkyl group having 1 to 14 carbon atoms, an alkenyl group having 2 to 14 carbon atoms, an alkynyl group having 2 to 14 carbon atoms, carbon, Represents an alkoxy group having 1 to 14 atoms, a cyano group (—CN), a nitro group (—NO ₂ ), and one or two or more CH ₂ groups in the alkyl group are not directly adjacent to each other. In addition, it may be substituted with -O-, -CO-, -OCO-, or -COO-, and one or more hydrogen atoms in the alkyl group, alkenyl group, alkynyl group, alkoxy group are It may be optionally substituted with a halogen atom.)
The compound represented by these is mentioned.
In the above formula (I-51), formula (I-54), formula (I-56) and formula (I-57), R ^{28 to} R ³⁸ are each an alkyl group having 1 to 10 carbon atoms, the number of carbon atoms An alkenyl group having 2 to 10 carbon atoms is preferable, and an alkyl group having 1 to 5 carbon atoms and an alkenyl group having 2 to 5 carbon atoms are more preferable.

Specific examples of the compound represented by the above formula (I-56) include those in which R ³³ and R ³⁴ are each a C ₂ H ₅ group.
Specific examples of the compound represented by the formula (I-57) include those in which R ^{35 to} R ³⁸ are each a C ₂ H ₅ group.

Among these compounds, an oligothiophene compound is preferable because the threshold value of the light intensity for response is low.
Further, a conjugated liquid crystal compound can also be used as the photoresponsive substance. As the liquid crystal compound that can function as such a photoresponsive substance, a rod-like liquid crystal compound is preferable.

Liquid crystal is used as the anisotropic molecule.
The liquid crystal preferably contains a compound represented by the following general formula (LC).

(In the general formula (LC), R ^LC represents an alkyl group having 1 to 15 carbon atoms, and one or two or more CH ₂ groups in the alkyl group are not directly adjacent to each other. -O-, -CH = CH-, -CO-, -OCO-, -COO- or C≡C- may be substituted, and one or more hydrogen atoms in the alkyl group are optionally May be substituted with a halogen atom,
A ^LC1 and A ^LC2 are each independently
(A) trans-1,4-cyclohexylene group (one CH ₂ group present in this group or two or more non-adjacent CH ₂ groups may be substituted with an oxygen atom or a sulfur atom) Good),
(B) 1,4-phenylene group (one CH group present in this group or two or more CH groups not adjacent to each other may be substituted with a nitrogen atom), and (c) 1,4-bicyclo (2.2.2) octylene group, naphthalene-2,6-diyl group, decahydronaphthalene-2,6-diyl group, 1,2,3,4-tetrahydronaphthalene-2,6- A diyl group or a group selected from the group consisting of a chroman-2,6-diyl group, but one or more hydrogen atoms contained in the group (a), group (b) or group (c) The atoms may be substituted with F, Cl, CF ₃ or OCF ₃ respectively.
Z ^LC is a single bond, —CH═CH—, —CF═CF—, —C≡C—, —CH ₂ CH ₂ —, — (CH ₂ ) ₄ —, —OCH ₂ —, —CH ₂ O—, _{-OCF 2 -, - CF 2 O} -, - COO- or OCO- represent,
Y ^LC represents a hydrogen atom, a fluorine atom, a chlorine atom, a cyano group, or an alkyl group having 1 to 15 carbon atoms, and one or two or more CH ₂ groups in the alkyl group are directly bonded to an oxygen atom. May be substituted with —O—, —CH═CH—, —CO—, —OCO—, —COO—, —C≡C—, —CF ₂ O—, —OCF ₂ — so as not to be adjacent, One or more hydrogen atoms in the alkyl group may be optionally substituted by halogen atoms;
a represents an integer of 1 to 4, but when a represents 2, 3 or 4, and there are a plurality of A ^LC1 , the plurality of A ^LC1 may be the same or different, and Z ^LC is When there are a plurality of Z ^LCs , the plurality of Z ^LCs may be the same or different. )

 The compounds represented by the general formula (LC) are represented by the following general formula (LC1) and general formula (LC2).

( ^Wherein R ^LC11 and R ^LC21 each independently represents an alkyl group having 1 to 15 carbon atoms, and one or more CH ₂ groups in the alkyl group are directly adjacent to each other with an oxygen atom. Not optionally substituted with —O—, —CH═CH—, —CO—, —OCO—, —COO— or C≡C—, wherein one or more of the alkyl groups hydrogen atom may be optionally substituted by a halogen atom, a ^LC11, and a ^LC21 are each independently any of the following structures

(In the structure, one or more CH ₂ groups in the cyclohexylene group may be substituted with an oxygen atom, and one or more CH groups in the 1,4-phenylene group are And one or more hydrogen atoms in the structure may be substituted with F, Cl, CF ₃ or OCF ₃ . ^{LC11, X LC12, X LC21 ~X} LC23 each independently represent a hydrogen atom, Cl, F, and CF _3, or OCF ^{_3, Y LC11} and ^{Y LC21} are each independently a hydrogen atom, Cl, F , CN, CF ₃ , OCH ₂ F, OCHF ₂ or OCF ₃ , Z ^LC11 and Z ^LC21 each independently represent a single bond, —CH═CH—, ^{—CF═CF—} , ^—C≡C— , _-CH 2 CH _{2 -, - (CH 2)} 4 -, - OCH 2 -, - CH 2 O -, - OCF 2 -, - CF 2 O -, - represents COO- or ^{OCO-, m LC11} and ^{m LC21} are each Independently, it represents an integer of 1 to 4, and when there are a plurality of A ^LC11 , A ^LC21 , Z ^LC11 and Z ^LC21 , they may be the same or different. )
It is preferable that it is 1 type, or 2 or more types of compounds chosen from the compound group represented by these.

R ^LC11 and R ^LC21 are each independently preferably an alkyl group having 1 to 7 carbon atoms, an alkoxy group having 1 to 7 carbon atoms, or an alkenyl group having 2 to 7 carbon atoms, and 1 to 5 carbon atoms. An alkyl group having 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms is more preferable, and a straight chain is more preferable, and the alkenyl group most preferably represents the following structure. .

(In the formula, it shall be bonded to the ring structure at the right end.)
A ^LC11 and A ^LC21 each independently preferably have the following structure.

Y ^LC11 and Y ^LC21 are each independently preferably F, CN, CF ₃ or OCF ₃ , preferably F or OCF ₃ , and particularly preferably F.
Z ^LC11 and Z ^LC21 are preferably a single bond, —CH ₂ CH ₂ —, ^—COO— , ^—OCO— , —OCH ₂ —, —CH ₂ O—, —OCF ₂ — or CF ₂ O—, , —CH ₂ CH ₂ —, —OCH ₂ —, —OCF ₂ — or CF ₂ O— are preferred, and a single bond, —OCH ₂ — or CF ₂ O— is more preferred.
m ^LC11 and m ^LC21 are preferably 1, 2 or 3, preferably 1 or 2 when emphasizing storage stability at low temperature and response speed, and 2 or 2 for improving the upper limit of the nematic phase upper limit temperature. 3 is preferred.
The general formula (LC1) is represented by the following general formula (LC1-a) to general formula (LC1-c).

^(Wherein, R ^LC11, Y ^{LC11, X LC11} and ^{X LC12} each independently represents the same meaning as ^{R LC11,} Y ^{LC11, X} LC11 and ^{X LC12} in the general formula ^{(LC1), A LC1a1, A LC1a2} and ^ALC1b1 represent a trans-1,4-cyclohexylene group, a tetrahydropyran-2,5-diyl group, and a 1,3-dioxane-2,5-diyl group, and ^XLC1b1 , ^XLC1b2 , ^XLC1c1 to X ^LC1c4 each independently represents a hydrogen atom, Cl, F, CF ₃ or OCF ₃ ), and is preferably one or more compounds selected from the group consisting of compounds represented by:
R ^LC11 is independently preferably an alkyl group having 1 to 7 carbon atoms, an alkoxy group having 1 to 7 carbon atoms, or an alkenyl group having 2 to 7 carbon atoms, and an alkyl group having 1 to 5 carbon atoms. And an alkoxy group having 1 to 5 carbon atoms and an alkenyl group having 2 to 5 carbon atoms are more preferable.
X ^{LC11 to} X ^LC1c4 are each independently preferably a hydrogen atom or F.
Y ^LC11 is preferably each independently F, CF ₃ or OCF ₃ .
The general formula (LC1) is changed from the following general formula (LC1-d) to the general formula (LC1-m).

^(Wherein, R ^LC11, Y ^{LC11, X LC11} and ^{X LC12} each independently represents the same meaning as ^{R LC11,} Y ^{LC11, X} LC11 and ^{X LC12} in the general formula ^{(LC1), A LC1d1, A LC1f1} , ^ALC1g1 , ^ALC1j1 , ^ALC1k1 , ^ALC1k2 , ^{ALC1m1 to ALC1m3} are 1,4-phenylene group, trans-1,4-cyclohexylene group, tetrahydropyran-2,5-diyl group, 1, It represents 3-dioxane-2,5-diyl ^{group, X LC1d1, X LC1d2, X} LC1f1, X LC1f2, X LC1g1, X LC1g2, X LC1h1, X LC1h2, X LC1i1, X LC1i2, X LC1j1 ~X LC1j4, X ^LC1k1 , X ^LC1k2 , X ^LC1m1 and ^{X LC1m2} are each independently a hydrogen atom, Cl, F, and CF _3, or _{^{OCF 3, Z LC1d1, Z LC1e1}} , Z LC1j1, Z LC1k1, Z LC1m1 are each independently a single bond, —CH═CH—, —CF═CF—, —C≡C—, —CH ₂ CH ₂ —, — (CH ₂ ) ₄ —, —OCH ₂ —, —CH ₂ O—, —OCF ₂ —, — CF ₂ O—, —COO— or OCO— is preferred), and it is preferably one or more compounds selected from the group consisting of compounds represented by:
R ^LC11 is independently preferably an alkyl group having 1 to 7 carbon atoms, an alkoxy group having 1 to 7 carbon atoms, or an alkenyl group having 2 to 7 carbon atoms, and an alkyl group having 1 to 5 carbon atoms. And an alkoxy group having 1 to 5 carbon atoms and an alkenyl group having 2 to 5 carbon atoms are more preferable.
X ^{LC11 to} X ^LC1m2 are each independently preferably a hydrogen atom or F.
Y ^LC11 is preferably each independently F, CF ₃ or OCF ₃ .
Z ^{LC1d1 to} Z ^LC1m1 are each independently preferably —CF ₂ O— or —OCH ₂ —.
The general formula (LC2) is represented by the following general formula (LC2-a) to general formula (LC2-g).

^{(Wherein, R LC21, Y LC21, X LC21} ~X LC23 each independently represents the same meaning as ^{R LC21, Y LC21, X LC21} ~X LC23 in the general formula ^{(LC2), X LC2d1} ~X ^{LC2d4, X LC2e1 ~X LC2e4, X} LC2f1 ~X LC2f4 and ^X LC2g1 ^{~X LC2g4} each independently represent a hydrogen atom, Cl, F, and CF _3, or _{^{OCF 3, Z LC2a1, Z LC2b1}} , Z LC2c1, Z ^LC2d1 , Z ^LC2e1 , Z ^LC2f1 and Z ^LC2g1 are each independently a single bond, —CH═CH—, ^{—CF═CF—} , ^—C≡C— , —CH ₂ CH ₂ —, — (CH ₂ ) ₄ −, —OCH ₂ —, —CH ₂ O—, —OCF ₂ —, —CF ₂ O—, —COO— Or OCO-.) It is preferably one or more compounds selected from the group consisting of compounds represented by:
R ^LC21 is each independently preferably an alkyl group having 1 to 7 carbon atoms, an alkoxy group having 1 to 7 carbon atoms, or an alkenyl group having 2 to 7 carbon atoms, and an alkyl group having 1 to 5 carbon atoms. And an alkoxy group having 1 to 5 carbon atoms and an alkenyl group having 2 to 5 carbon atoms are more preferable.
X ^{LC21 to} X ^LC2g4 are each independently preferably a hydrogen atom or F,
Y ^LC21 is preferably each independently F, CF ₃ or OCF ₃ .
Z ^{LC2a1 to} Z ^LC2g4 are each independently preferably —CF ₂ O— or —OCH ₂ —.
The compounds represented by the general formula (LC) are represented by the following general formula (LC3) to general formula (LC5).

^{(Wherein, R LC31, R LC32, R} LC41, R LC42, R LC51 and ^{R LC52} each independently represent an alkyl group having 1 to 15 carbon atoms, one or two in the alkyl group The above CH ₂ groups may be substituted with —O—, —CH═CH—, —CO—, —OCO—, —COO— or C≡C— so that oxygen atoms are not directly adjacent to each other, one or more hydrogen atoms in the alkyl group may be optionally substituted by a halogen ^{atom, a LC31, a LC32, a} LC41, a LC42, a LC51 and ^{a LC52} are each independently , Any of the following structures

(In the structure, one or more CH ₂ groups in the cyclohexylene group may be substituted with an oxygen atom, and one or more CH groups in the 1,4-phenylene group are Z may be substituted with a nitrogen atom, and one or more hydrogen atoms in the structure may be substituted with Cl, CF ₃ or OCF ₃ ) ^{LC31, Z LC32, Z LC41,} Z LC42, Z LC51 and ^{Z LC51} are each independently a single bond, -CH = CH -, - C≡C -, - CH 2 CH 2 -, - (CH 2) _{4 -, - COO -, -} OCH 2 -, - CH 2 O -, - OCF 2 - or _CF 2 O-to represent, ^{Z 5} represents a CH ₂ group or an oxygen ^{atom, X LC41} is a hydrogen atom or It represents a fluorine ^{atom, m LC31,} m ^{C32, m LC41, m LC42,} m LC51 and ^{m LC52} each independently represent ^{0~3, m LC31 + m LC32,} m LC41 + m LC42 and ^m LC51 ^{+ m LC52} is 1, 2 or 3, When a plurality of A ^{LC31 to} A ^LC52 and Z ^{LC31 to} Z ^LC52 are present, they may be the same or different. It is preferable that it is 1 type, or 2 or more types of compounds chosen from the compound group represented by this.
R ^{LC31 to} R ^LC52 are each independently preferably an alkyl group having 1 to 7 carbon atoms, an alkoxy group having 1 to 7 carbon atoms, or an alkenyl group having 2 to 7 carbon atoms. Most preferably,

(In the formula, it shall be bonded to the ring structure at the right end.)
A ^{LC31 to} A ^LC52 each independently preferably have the following structure:

Z ^{LC31 to} Z ^LC51 each independently represent a single bond, —CH ₂ O—, —COO—, ^—OCO— , —CH ₂ CH ₂ —, —CF ₂ O—, —OCF ₂ — or OCH ₂ —. Is preferred.
The general formula (LC3) is represented by the following general formula (LC3-a) and general formula (LC3-b).

(Wherein R ^LC31 , R ^LC32 , A ^LC31 and Z ^LC31 each independently represent the same meaning as R ^LC31 , R ^LC32 , A ^LC31 and Z ^LC31 in the general formula (LC3), and X ^{LC3b1 to} X ^{LC3 LC3b6} represents a hydrogen atom or a fluorine atom, but at least one of X ^LC3b1 and X ^LC3b2 or X ^LC3b3 and X ^LC3b4 represents a fluorine atom, and m ^LC3a1 is 1, 2 or 3. m ^LC3b1 represents 0 or 1, and when a plurality of A ^LC31 and Z ^LC31 are present, they may be the same or different.) One or two selected from the compound group represented by The above compounds are preferable.
R ^LC31 and R ^LC32 each independently represent an alkyl group having 1 to 7 carbon atoms, an alkoxy group having 1 to 7 carbon atoms, an alkenyl group having 2 to 7 carbon atoms, or an alkenyl group having 2 to 7 carbon atoms. It preferably represents an oxy group.
A ^LC31 preferably represents a 1,4-phenylene group, a trans-1,4-cyclohexylene group, a tetrahydropyran-2,5-diyl group, or a 1,3-dioxane-2,5-diyl group. , 4-phenylene group and trans-1,4-cyclohexylene group are more preferable.
Z ^LC31 is a single _{bond, -CH 2 O -, - COO} -, - OCO -, - CH 2 CH 2 - is preferred to represent, and more preferably a single bond.
The general formula (LC3-a) preferably represents the following general formula (LC3-a1) to general formula (LC3-a4).

(In the formula, R ^LC31 and R ^LC32 each independently represent the same meaning as R ^LC31 and R ^LC32 in General Formula (LC3).)
R ^LC31 and R ^LC32 are each independently preferably an alkyl group having 1 to 7 carbon atoms, an alkoxy group having 1 to 7 carbon atoms, or an alkenyl group having 2 to 7 carbon atoms, and R ^LC31 is the number of carbon atoms. More preferably, it represents an alkyl group having 1 to 7 and R ^LC32 represents an alkoxy group having 1 to 7 carbon atoms.
The general formula (LC3-b) preferably represents the following general formula (LC3-b1) to general formula (LC3-b12). The following general formula (LC3-b1) and the following general formula (LC3-b6) The following general formula (LC3-b8) and the following general formula (LC3-b11) are more preferable, the following general formula (LC3-b1) and the general formula (LC3-b6) are more preferable. Most preferably, it represents the formula (LC3-b1).

(In the formula, R ^LC31 and R ^LC32 each independently represent the same meaning as R ^LC31 and R ^LC32 in General Formula (LC3).)
R ^LC31 and R ^LC32 are each independently preferably an alkyl group having 1 to 7 carbon atoms, an alkoxy group having 1 to 7 carbon atoms, or an alkenyl group having 2 to 7 carbon atoms, and R ^LC31 is the number of carbon atoms. More preferably, it represents 2 or 3 alkyl groups, and R ^LC32 represents an alkyl group having 2 carbon atoms.
The general formula (LC4) is represented by the following general formula (LC4-a) to general formula (LC4-c), and the general formula (LC5) is represented by the following general formula (LC5-a) to general formula (LC5-c).

^{(Wherein, R LC41,} R ^LC42 and ^{X LC41} each independently represents the same meaning as ^{R LC41, R LC42} and ^{X LC41} in the general formula ^{(LC4), R LC51} and ^{R LC52} are each independently Te represents the same meaning as ^{R LC51} and ^{R LC52} in the general formula ^{(LC5), Z LC4a1, Z} LC4b1, Z LC4c1, Z LC5a1, Z LC5b1 and ^{Z LC5c1} are each independently a single bond, -CH = CH—, —C≡C—, —CH ₂ CH ₂ —, — (CH ₂ ) ₄ —, —COO—, —OCH ₂ —, —CH ₂ O—, —OCF ₂ — or CF ₂ O— is represented. It is more preferable that it is 1 type, or 2 or more types of compounds selected from the group consisting of compounds represented by.
^{R LC41,} R LC42, R ^LC51 and ^{R LC52} are each independently an alkyl group having 1 to 7 carbon atoms, an alkoxy group having 1 to 7 carbon atoms, an alkenyl group or a carbon atom of 2 to 7 carbon atoms It preferably represents an alkenyloxy group having a number of 2 to 7.
Z ^{LC4a1 to} Z ^LC5c1 each independently preferably represent a single bond, —CH ₂ O—, ^—COO— , ^—OCO— , —CH ₂ CH ₂ —, and more preferably represent a single bond.
The compound represented by the general formula (LC) is represented by the following general formula (LC6).

(In the formula, R ^LC61 and R ^LC62 each independently represent an alkyl group having 1 to 15 carbon atoms, and one or two or more CH ₂ groups in the alkyl group are directly adjacent to each other with an oxygen atom. Not optionally substituted with —O—, —CH═CH—, —CO—, —OCO—, —COO— or C≡C—, wherein one or more of the alkyl groups The hydrogen atom may be optionally halogen-substituted, and A ^{LC61 to} A ^LC63 are each independently described below.

(In the structure, one or more CH ₂ CH ₂ groups in the cyclohexylene group may be substituted with —CH═CH—, —CF ₂ O—, —OCF ₂ —, One or two or more CH groups in the 4-phenylene group may be substituted with a nitrogen atom), and Z ^LC61 and Z ^LC62 each independently represent a single bond, —CH ═CH—, —C≡C—, —CH ₂ CH ₂ —, — (CH ₂ ) ₄ —, —COO—, —OCH ₂ —, —CH ₂ O—, —OCF ₂ — or CF ₂ O—. ^Miii1 represents 0-3. However, the compound represented by the general formula (LC1) to the general formula (LC5) is excluded. A liquid crystal composition containing one or more compounds represented by formula (1) is preferred.
R ^LC61 and R ^LC62 are each independently preferably an alkyl group having 1 to 7 carbon atoms, an alkoxy group having 1 to 7 carbon atoms, or an alkenyl group having 2 to 7 carbon atoms. Most preferably,

(In the formula, it shall be bonded to the ring structure at the right end.)
A ^{LC61 to} A ^LC63 each independently preferably have the following structure:

Z ^LC61 and Z ^LC62 are each independently ^preferably a single bond, —CH ₂ CH ₂ —, ^—COO— , —OCH ₂ —, —CH ₂ O—, —OCF ₂ — or CF ₂ O—.
The general formula (LC6) is represented by the following general formula (LC6-a) to general formula (LC6-m).

(In the formula, R ^LC61 and R ^LC62 each independently represent an alkyl group having 1 to 7 carbon atoms, an alkoxy group having 1 to 7 carbon atoms, an alkenyl group having 2 to 7 carbon atoms, or 2 carbon atoms. It is more preferable that it is 1 type, or 2 or more types of compounds chosen from the group which consists of a compound represented by -7 alkenyloxy group.

Further, the liquid crystal may be any of a rod-like liquid crystal (nematic liquid crystal, smectic liquid crystal), a disk-like (discotic) liquid crystal, a bent liquid crystal (banana liquid crystal), and a liquid crystal obtained by adding chirality thereto.
The shape of the liquid crystal (bar-shaped, disk-shaped, or bent-type) is appropriately selected in order to obtain a desired refractive index anisotropy. When fast response is required, nematic liquid crystal that is liquid crystal close to liquid is preferable. When stable orientation is required, it is preferable to use smectic liquid crystal close to solid. A liquid crystal phase peculiar to a chiral liquid crystal can also be used. In that case, a part or all of the liquid crystal may be chiral, or a liquid crystal and a chiral non-liquid crystal may be mixed. The liquid crystal may be any of a monomer, a dimer, a multimer (oligomer) of trimer or higher, and a polymer (polymer). Monomers are preferred when quick responsiveness is required, and dimers, multimers higher than trimers (oligomers), and polymers (polymers) are preferred when stable orientation is required.

The molar ratio of the photoresponsive substance in the photoresponsive composition is preferably 0.01 mol% or more and 30 mol% or less, and more preferably 0.05 mol% or more and 10 mol% or less.
If the ratio of the photoresponsive substance in the photoresponsive composition is within the above range, the photoresponsive composition is irradiated with light having a light intensity equal to or higher than a threshold value, and the photoresponsive substance is aligned. The anisotropic molecules contained in the photoresponsive composition can be easily oriented in any direction.
Here, the arbitrary direction in which the photoresponsive substance and the anisotropic molecule are aligned is a direction in which the major axis direction of these substances (molecules) is parallel to the vibration direction of light.

The photoresponsive composition can contain oligomers and / or polymers to reduce the light intensity threshold.
In this case, the oligomer and / or polymer may be mixed in the photoresponsive composition, or a low molecular compound having a polymerizable group may be mixed before polymerization.
Examples of the oligomer and / or polymer include polyacrylate, polymethacrylate, polyacrylamide, polymethacrylamide, polymethyl methacrylate and the like. The degree of polymerization or the presence or absence of liquid crystallinity may be determined in consideration of the solubility in the photoresponsive composition.

 The low molecular compound having a polymerizable group may or may not have liquid crystallinity, but preferably has liquid crystallinity. Note that “showing liquid crystallinity” means having a rigid portion called a mesogen and showing orientation. Examples of the polymerizable compound exhibiting liquid crystallinity include, for example, Handbook of Liquid Crystals (D. Demus, JW Goodby, GW Gray, HW Spies, V. Vill, edited by Wiley-VCH, 1998), Quarterly Chemical Review No. 22, Liquid Crystal Chemistry (Edited by Chemical Society of Japan, 1994), or JP-A-7-294735, JP-A-8-3111, JP-A-8-29618, JP-A-11-80090, 1,4-phenylene group, 1,4-cyclohexene, as described in Kaihei 11-148079, JP-A 2000-178233, JP-A 2002-308831, and JP-A 2002-145830. A rod-like polymerizable liquid crystal compound having a rigid site called a mesogen in which a plurality of structures such as a silene group are connected, and a polymerizable functional group such as a (meth) acryloyloxy group, a vinyloxy group, and an epoxy group, or JP-A-2004-2373 And a rod-like polymerizable liquid crystal compound having a maleimide group as described in JP 2004-99446 A Alternatively, a rod-like polycyclic liquid crystal compound having an allyl ether group as described in JP-A-2004-149522, or, for example, Handbook of Liquid Crystals (D. Demus, JW Goodbye, G. W. Gray, H. W. Spiess, edited by V. Vill, published by Wiley-VCH, 1998), Quarterly Chemical Review No. 22. Liquid crystal chemistry (edited by Chemical Society of Japan, 1994) and discotic polymerizable compounds described in JP-A-07-146409.

The total content of the oligomer and / or polymer in the photoresponsive composition is preferably 0.1 mol% or more and 15 mol% or less, more preferably 2 mol% or more and 13 mol% or less, and more preferably 5 mol / Lmol. % Or more and 11 mol / L or less% is more preferable.
If the content of the oligomer and / or polymer in the photoresponsive composition is within the above range, the light intensity threshold of light can be reduced.

 When an oligomer is added to the photoresponsive composition, the polymerization proceeds even when no polymerization initiator is present, but a polymerization initiator may be contained in order to accelerate the polymerization. Examples of the polymerization initiator include benzoin ethers, benzophenones, acetophenones, benzyl ketals, acylphosphine oxides, and the like.

The light intensity threshold (minimum value) necessary for the orientation of the photoresponsive composition having such a configuration is preferably 10 W / cm ² or less in order to reduce the light intensity to be irradiated. It is more preferably 5 W / cm ² or less, and further preferably 1 W / cm ² or less. Further, in order to control to be oriented at a specific light intensity, it is preferable to adjust the required light intensity threshold value to be in a specific range.
The threshold value of the light intensity necessary for orienting the photoresponsive composition is the minimum value of the light intensity necessary for orienting the anisotropic molecules along with the orientation of the photoresponsive substance. That is.
That is, in the photoresponsive composition according to the present invention, anisotropic molecules are oriented as the photoresponsive substance is oriented by light irradiation.

Further, the thickness of the layer containing the photoresponsive composition in the optical element of the present invention is preferably 3 μm or more, more preferably 10 μm or more, and further preferably 100 μm or more.
When the thickness of the layer containing the photoresponsive composition is within the above range, the threshold value of light intensity necessary for orienting the photoresponsive composition can be lowered.

In the optical element of the present invention, when the photoresponsive composition is irradiated with light, the photoresponsive substance contained in the photoresponsive composition is arranged so that the major axis direction thereof is parallel to the vibration direction of the light. As it is aligned, the anisotropic molecules are aligned so that their long axis direction is parallel to the vibration direction of light. Therefore, light transmission is performed using the birefringence of anisotropic molecules (liquid crystal). It is applied to a liquid crystal display element that controls the amount of light.
As liquid crystal display elements, AM-LCD (active matrix liquid crystal display element), TN (twisted nematic liquid crystal display element), STN-LCD (super twisted nematic liquid crystal display element), OCB-LCD, IPS-LCD (in-plane switching) Although it is useful for liquid crystal display elements) and FFS (fringe field switching mode liquid crystal display elements), it is particularly useful for AM-LCDs having an active matrix addressing device, and is used for transmissive or reflective liquid crystal display elements. it can.

When the optical element is the liquid crystal display element 10, the two substrates of the liquid crystal cell used in the liquid crystal display element 10 can be made of a transparent material having flexibility such as glass or plastic. One of the two substrates may be an opaque material such as silicon. A transparent substrate having a transparent electrode layer can be obtained, for example, by sputtering indium tin oxide (ITO) on a transparent substrate such as a glass plate.
The color filter can be produced by, for example, a pigment dispersion method, a printing method, an electrodeposition method, or a dyeing method. A method for producing a color filter by a pigment dispersion method will be described as an example. A curable coloring composition for a color filter is applied onto the transparent substrate, subjected to patterning treatment, and cured by heating or light irradiation. By performing this process for each of the three colors red, green, and blue, a pixel portion for a color filter can be manufactured. In addition, a pixel electrode provided with an active element such as a TFT, a thin film diode, or a metal insulator metal specific resistance element may be provided on the substrate.

 Moreover, the said board | substrate may be made to oppose so that a transparent electrode layer may become an inner side, and you may adjust the space | interval of a board | substrate through a spacer. In this case, the thickness of the obtained liquid crystal layer is preferably 3 μm or more, more preferably 10 μm or more, and further preferably 100 μm or more. When a polarizing plate is used, it is preferable to adjust the product of the refractive index anisotropy Δn of the liquid crystal and the cell thickness d so that the contrast is maximized. In addition, when there are two polarizing plates, the polarizing axis of each polarizing plate can be adjusted so that the viewing angle and contrast are good. Furthermore, a retardation film for widening the viewing angle can also be used. Examples of the spacer include columnar spacers made of glass particles, plastic particles, alumina particles, photoresist materials, and the like. Thereafter, a sealing agent such as an epoxy thermosetting composition is screen-printed on the substrates in a form provided with a liquid crystal injection port, the substrates are bonded to each other, heated, and the sealing agent is thermally cured.

When the optical element is the liquid crystal display element 10, the photoresponsive composition is formed on the first substrate surface (the substrate 11 in FIG. 1) on the first substrate (for example, the substrate 11 in FIG. 1) side. 12 is opposed to the substrate 11 in the substrate 12 in FIG. 1 on the second substrate (for example, the substrate 12 in FIG. 1) side. It is preferably oriented perpendicular to the surface 12a).
Thus, the threshold value of the light intensity necessary for orienting the photoresponsive composition by making the orientation direction of the photoresponsive composition different between the first substrate side and the second substrate side. Can be lowered.

 According to the optical element of the present invention, the light intensity greater than or equal to the threshold at which the photoresponsive substance responds to the photoresponsive composition containing the photoresponsive substance having a threshold value in the light intensity to be responsive and the anisotropic molecule. The photoresponsive material contained in the photoresponsive composition is oriented by irradiating with light, and the anisotropic molecules are oriented accordingly. Therefore, the light intensity required for the anisotropic molecules to be oriented Can be lowered.

[Method for Manufacturing Optical Element]
The method for producing an optical element of the present invention is a method for producing the above-described optical element of the present invention, which includes a photoresponsive substance having a threshold in response light intensity and an anisotropic molecule. It is a method having a step of orienting the photoresponsive composition by irradiating the composition with light having a light intensity equal to or higher than a threshold value.

 As the photoresponsive substance and the anisotropic molecule, those similar to those used for the optical element of the present invention are used.

 The photoresponsive composition can further contain an oligomer and / or a polymer, as in the optical element of the present invention.

In the method for producing an optical element of the present invention, first, a photoresponsive composition is sandwiched between two substrates.
As a method of sandwiching the photoresponsive composition between the two substrates, a normal vacuum injection method, a drop injection (ODF: One Drop Fill) method, or the like can be used.

 After the photoresponsive composition is sandwiched between the two substrates, the light having a light intensity equal to or higher than the threshold value required for orienting the photoresponsive material contained in the photoresponsive composition to the photoresponsive composition. By irradiating light with intensity and orienting the photoresponsive substance so that its long axis direction is parallel to the vibration direction of light, anisotropic molecules can vibrate in the long axis direction of light. Oriented to be parallel to the direction.

 Moreover, when an oligomer is contained in a photoresponsive composition, it is preferable to polymerize the oligomer with the light irradiated to the photoresponsive composition.

In addition, when irradiating the photoresponsive composition with light, it is preferable to irradiate the light with which the photoresponsive composition is irradiated at an angle with respect to the normal direction of the layer containing the photoresponsive composition. The angle is more preferably 0 ° or more and 15 ° or less, and further preferably 0 ° or more and 10 ° or less with respect to the normal direction of the layer containing the photoresponsive composition.
By irradiating light irradiating the photoresponsive composition at an angle with respect to the normal direction of the layer containing the photoresponsive composition, for example, before photoirradiation, the photoresponsive substance Even when the major axis direction is oriented perpendicular to the vibration direction of light, light can be irradiated from an oblique direction with respect to the major axis direction of the photoresponsive substance. Thereby, the photoresponsive substance can be efficiently oriented so that the long axis direction is parallel to the vibration direction of light. Furthermore, when irradiating the photoresponsive composition with light, the angle of the layer containing the photoresponsive composition with respect to the normal direction is 10 degrees or less, so that the photoresponsive substance can be more efficiently The major axis direction can be oriented so as to be parallel to the vibration direction of light.

When the photoresponsive composition is irradiated with light, the temperature is preferably within a temperature range in which the liquid crystal state is maintained when the anisotropic molecule contained in the photoresponsive composition is a liquid crystal. It is preferable to irradiate light at a temperature close to room temperature, that is, typically at a temperature of 15 to 35 ° C.
A metal halide lamp, a high-pressure mercury lamp, an ultrahigh-pressure mercury lamp, or the like can be used as a light source that generates light to be irradiated to the photoresponsive composition.
In addition, the intensity of light applied to the photoresponsive composition is required for the photoresponsive substance contained in the photoresponsive composition to align its long axis direction parallel to the vibration direction of light. It is not less than the threshold value of light intensity (minimum value of light intensity), preferably 10 W / cm ² or less, more preferably 5 W / cm ² or less, and further preferably 1 W / cm ² or less.
The time for irradiating light is appropriately selected depending on the intensity of the irradiated light, but is preferably 10 seconds to 3600 seconds, and more preferably 10 seconds to 600 seconds.

When the optical element is the liquid crystal display element 10, the photoresponsive composition is placed on the first substrate surface (the substrate 11 in FIG. 1) on the first substrate (for example, the substrate 11 in FIG. 1) side. In the second substrate (in FIG. 1, for example, the substrate 12) side, the second substrate surface (in FIG. 1, the substrate 12 in the substrate 12 and the substrate 11 in FIG. It is preferable to irradiate the light-responsive composition with light having a light intensity equal to or greater than a threshold value after being oriented perpendicular to the opposing surface 12a).
Thus, in order to orient the anisotropic molecules contained in the photoresponsive composition by making the orientation direction of the photoresponsive composition different between the first substrate side and the second substrate side. It is possible to reduce the threshold value of the light intensity required for.

 According to the method for producing an optical element of the present invention, light having a light intensity equal to or higher than a threshold is applied to a photoresponsive composition containing a photoresponsive substance having a threshold value in response light intensity and an anisotropic molecule. By irradiating, the anisotropic molecules are oriented, so that the threshold value of the light intensity at which the anisotropic molecules are oriented can be lowered.

 EXAMPLES Hereinafter, although an Example is given and this invention is further explained in full detail, this invention is not limited to these Examples.

[Example 1]
The following formula (II)

A compound represented by the following formula (III) and an acrylate monomer (A4CB) having a cyanobiphenyl skeleton as a polymerization site are mixed at a molar ratio of 87/13 to obtain a composition (A -1) was prepared.

 99.4 mol% of this composition (A-1), 0.1 mol% of photoresponsive substance (oligothiophene TR5, manufactured by Merck & Co.) represented by the following formula (IV), and light having absorption only in the ultraviolet region A polymerization sample was prepared by adding 0.5 mol% of a polymerization initiator (trade name: Irgacure 651, manufactured by Nagase Sangyo Co., Ltd.).

Next, two glass substrates that have been subjected to a vertical alignment treatment using a silane coupling agent are bonded so that the surface on which the alignment treatment has been performed is on the inside, thereby producing a glass cell having a thickness (cell gap) of 100 μm. did.
Next, the prepared polymerization sample was sealed in the glass cell (between two glass substrates) and photopolymerized at room temperature (25 ° C.).
Photopolymerization was performed by taking out a bright line of a high-pressure mercury lamp having a wavelength of 366 nm with a filter and irradiating it with light having a light intensity of 1.0 mW / cm ² for 1 hour.
After photopolymerization, the sample was gradually cooled from 70 ° C. to room temperature (25 ° C.) to obtain Sample 1-1 of Example 1.

 When the sample 1-1 was observed with a polarizing microscope (trade name: Olympus BX50, manufactured by Olympus), a cross isogyre was confirmed in the conoscopic image, and a dark field was confirmed in the orthoscope image. Therefore, it was found that the polymer-aligned liquid crystal containing a dye has a homeotropic alignment in which the molecular alignment is perpendicular to the glass substrate.

 Moreover, the polarization absorption spectrum measurement of the sample 1-1 was performed, and the ultraviolet visible absorption spectrum of the homeotropic cell was measured. In Sample 1-1, since the molecules are vertically aligned, it has been found that the light having a wavelength of 488 nm has an absorbance of about 0.15 derived from the dye molecules with respect to polarized light in the vertical and horizontal directions. .

Next, in order to estimate the degree of molecular orientation, two glass substrates on which a polyimide alignment film has been rubbed are prepared, and bonded together using the above-mentioned polymerization sample so that the rubbing direction is antiparallel. (Sample 1-2 of Example 1) was prepared, and the order parameter of each sample was calculated. The order parameter (S) is obtained by measuring the UV-visible absorption spectrum of each sample, and measuring the absorbance in the direction parallel to the rubbing direction as A ₀ and the absorbance in the direction perpendicular to the rubbing direction as A _90. = (A ₀ -A ₉₀ ) / (A ₀ + 2A ₉₀ )
Sample 1-2 containing the polymer-stabilized liquid crystal prepared by photopolymerization was found to have a reduced order parameter of the dye molecules as compared with the sample of Comparative Example 1 below. Therefore, even in the homeotropic alignment cell, it is considered that the degree of alignment of the dye molecules may be lowered in the sample containing the polymer-stabilized liquid crystal.

In addition, the photoresponse behavior was measured.
For this observation, an Ar ⁺ laser having a beam diameter of 2.0 mm and a wavelength of 488 nm was used as pump light. The pump light is converted into vertical vertical polarization using a Glan-Thompson prism, condensed with a lens having a focal length of 15 cm, irradiated onto the sample 1-1, and the light transmitted through the sample 1-1 is projected onto a screen and observed. .

Here, the principle of measurement will be described.
When light having a Gaussian intensity distribution is incident on the liquid crystal, the molecules do not change their orientation at a light intensity lower than the threshold value, and the incident light is transmitted as it is. However, when light having an intensity equal to or higher than the threshold is irradiated, the molecular orientation of the liquid crystal changes depending on the light intensity, and a Gaussian-type refractive index gradient is formed. Here, since the liquid crystal plays a role as a lens, phase modulation is performed by a refractive index gradient created by incident light itself, and a self-convergence effect and a self-phase modulation effect appear. Therefore, the light transmitted through the liquid crystal interferes with light having different phases and exhibits such interference fringes. Here, the interference fringes formed by the pump light transmitted through the sample were projected onto a distant screen for observation.
As a result, it was found that when the pump light intensity exceeds the threshold value, interference fringes are generated and the number thereof increases rapidly. Further, when the light intensity was lowered, the number of interference fringes reversibly decreased and disappeared.
Moreover, since the increase in the number of interference fringes was steep with respect to the light intensity, it was found that the nonlinearity was greatly improved.

Further, for the sample 1-1, the light intensity at which the first interference fringe appears is measured using a beam profiler, and the threshold value (minimum value) of the light intensity at which the first interference fringe appears on the sample 1-1. ) In detail, it was 4.6 W / cm ² , which was found to be significantly lower than the result of Comparative Example 1 below.

Here, if attention is paid to the difference in the system regarding the reason why the threshold value of the light intensity is lowered, the following two reasons can be considered.
(1) An increase in viscosity can be considered due to the mixing of a crystalline monomer or solid polymer with a host liquid crystal exhibiting a nematic liquid crystal phase at room temperature. As a result, the alignment regulating force on the substrate surface in the vertical alignment cell is weakened, and there is a possibility that a response is shown even for a smaller photoelectric field.
(2) It is considered that the order parameter of the dye molecules in the polymer-stabilized liquid crystal is reduced by photopolymerization. Therefore, there is a possibility that the torque from the photoelectric field acting on the dye molecule is increased and the orientation change efficiency is improved.

Next, in order to quantitatively evaluate the decrease in the orientation regulating force due to the increase in viscosity, two glass substrates with ITO electrodes are prepared, and the homogeneous sample (the sample of Example 1) is prepared using the above sample for polymerization. 1-3) was produced.
When a voltage is applied to the homogeneous cell, the liquid crystal is homeotropically aligned, so that light is not transmitted from the polarizer and the analyzer that form 45 degrees with respect to the rubbing direction. On the other hand, when the application of the voltage to the homogeneous cell is stopped, light returns to the initial homogeneous alignment due to the influence of the alignment film.
Therefore, the change in the amount of transmitted light of the probe light was measured every 1 ms from immediately after stopping the voltage application until returning to the initial state. As a result, when the relaxation times were compared, it was found that in Sample 1-3 containing the polymer-stabilized liquid crystal, the relaxation time was remarkably increased, and the alignment regulating force in the cell was decreased as the viscosity increased. . This can be interpreted that in Sample 1-3 containing polymer-stabilized liquid crystal, the alignment regulating force is weakened, and the threshold value when the photoelectric field interacts with the dye molecule decreases.

Therefore, it was confirmed whether or not photoresponsiveness could be further improved by weakening the orientation regulating force in the film thickness direction by producing a cell having a larger thickness and performing light irradiation.
As a result, it was found that light intensity required to induce equal birefringence was reduced when light was irradiated to cells of 100 μm, 200 μm, and 400 μm thickness with molecules aligned vertically. As a result, the threshold value of the light intensity became 2.3 W / cm ² by increasing the thickness by 4 times (400 μm).

 Another reason why the light intensity threshold is lowered is that the order parameter of the dye in the polymer-stabilized liquid crystal is decreased by photopolymerization. That is, the initial orientation of the dye molecules is slightly disturbed from the orientation perpendicular to the photo electric field, so that the photo electric field and the tilted dye molecules are likely to interact, and the dye molecules that trigger the nonlinear optical molecular orientation change It is believed that photomolecular orientation changes are induced at lower light intensity.

Therefore, the effect of the initial tilt angle of the dye molecules on the orientation change efficiency was quantitatively evaluated.
The sample 1-1 was irradiated with light in a state where the sample 1-1 having a thickness of 100 μm was tilted in parallel with the plane of polarization of the incident light, and the dependence of the photoresponsiveness on the incident angle was examined. By increasing the angle at which the sample 1-1 was tilted, a result that the threshold value of the light intensity was significantly reduced was obtained. In particular, when the angle at which the sample 1-1 is tilted is in the range of 1 to 10 degrees, the light intensity threshold is remarkably lowered to 1.5 W / cm ² even though the absorbance of the sample 1-1 hardly changes. became.

 When the angle at which the sample 1-1 is tilted is 0 degree, the molecules are oriented perpendicular to the electric field direction of the incident light. Since the generated bi-directional torques cancel each other, high light intensity is required to induce uniaxial orientation. On the other hand, by slightly tilting the sample 1-1, the photoelectric field and the tilted dye molecules can easily interact with each other, and the molecular orientation direction is defined as one direction. It is thought to be induced by strength.

From the above results, it is considered that the molecular orientation can be induced with a lower light intensity by optimizing the thickness of the vertically oriented molecules and the tilt angle of the sample with respect to the direction parallel to the polarization plane of the incident light.
Therefore, a sample containing a polymer-stabilized liquid crystal having a thickness of 400 μm in which molecules are vertically aligned is tilted with respect to a direction parallel to the polarization plane of incident light, and the sample is irradiated with light. When the intensity threshold value was examined, the light intensity threshold value was 900 mW / cm ² .

[Comparative Example 1]
A sample prepared by adding 0.1 mol% of the photoresponsive substance represented by the above formula (IV) to the compound represented by the above formula (II) instead of the polymerization sample prepared in Example 1 was prepared. A cell was produced in the same manner as in Example 1 except that it was used, and Sample 1′-1 of Comparative Example 1 was obtained.
When the sample 1′-1 was observed with a polarizing microscope in the same manner as in Example 1, it was confirmed that a cross isogyre was observed in the conoscopic image and a dark field was observed in the orthoscope image.
Moreover, the polarization absorption spectrum measurement of the sample 1-1 was performed. In Sample 1′-1, since the molecules are vertically aligned, it is understood that the light having a wavelength of 488 nm has an absorption of about 0.14 derived from the dye molecules with respect to polarized light in the vertical direction and the horizontal direction. It was.
Further, in order to estimate the degree of molecular orientation order, a homogeneous cell (sample 1′-2 of Comparative Example 1) was prepared in the same manner as in Example 1, and the order parameters of each sample were calculated. The order parameter of the dye molecule did not decrease.
Further, in the same manner as in Example 1, the light intensity is measured by using a beam profiler, the light intensity at which the first interference fringe appears, and the first interference fringe appears on the sample 1′-1. When the threshold value (minimum value) of light intensity was examined in detail, it was 28 W / cm ² .

[Example 2]
A compound represented by the above formula (II) and an acrylate monomer (A4CB) represented by the above formula (III) and having a cyanobiphenyl skeleton as a polymerization site are mixed at a molar ratio of 90/10. A composition (B-1) was prepared.

 99.4 mol% of this composition (B-1), 0.1 mol% of photoresponsive substance (oligothiophene TR5, manufactured by Merck & Co.) represented by the above formula (IV), and light having absorption only in the ultraviolet region A polymerization sample was prepared by adding 0.5 mol% of a polymerization initiator (trade name: Irgacure 651, manufactured by Nagase Sangyo Co., Ltd.).

Next, the glass substrate that has been subjected to the vertical alignment treatment with the silane coupling agent and the glass substrate that has been subjected to the horizontal alignment treatment with the polyimide alignment film are bonded so that the surface on which the alignment treatment has been performed is on the inside. A glass cell having a cell gap of 100 μm was produced.
Next, the prepared polymerization sample was sealed in the glass cell (between two glass substrates) and photopolymerized at room temperature (25 ° C.).
Photopolymerization was performed by taking out a bright line of a high-pressure mercury lamp having a wavelength of 366 nm with a filter and irradiating it with light having a light intensity of 1.0 mW / cm ² for 1 hour.
After photopolymerization, the sample was slowly cooled from 70 ° C. to room temperature (25 ° C.) to obtain a sample 2-1 of Example 2 which was hybrid-oriented.

The sample 2-1 was irradiated with Ar ⁺ laser light having a beam diameter of 2.0 mm and a wavelength of 488 nm as pump light so that the polarization direction was parallel to the homogeneous alignment processing direction from the homeotropic alignment processing substrate side. The light response behavior was measured in the same manner as in Example 1.
As a result, it was found that the threshold value of the light intensity at which the polymerization sample responds (orients) is as low as 0.57 W / cm ² . That is, it was found that a hybrid alignment cell using a glass substrate subjected to vertical alignment treatment and a glass substrate subjected to horizontal alignment treatment has an effect of reducing the threshold value of light intensity.

Example 3
The following formula (LC-7)

The acrylate monomer (A4CB) represented by the above formula (III) and having a cyanobiphenyl skeleton as a polymerization site is mixed at a molar ratio of 87/13 to obtain a composition (C -1) was prepared.
A cell was produced in the same manner as in Example 1 except that the composition (C-1) was used instead of the composition (A-1) prepared in Example 1, and Sample 3-1 in Example 3 was prepared. Obtained.

 Sample 3-1 was observed with a polarizing microscope in the same manner as in Example 1. As a result, it was confirmed that a cross isogyre was observed in the conoscopic image and a dark field was observed in the orthoscope image.

 Moreover, the polarization absorption spectrum measurement of the sample 3-1 was performed. In Sample 3-1, since the molecules are vertically aligned, it has been found that the light having a wavelength of 488 nm has an absorption of about 0.15 derived from the dye molecules with respect to polarized light in the vertical and horizontal directions. .

 Next, in order to estimate the degree of molecular orientation order, two glass substrates on which a polyimide alignment film was rubbed were prepared. Using the composition (C-1), a homogeneous cell (Sample 3 of Example 3) was prepared. When 2) was prepared and the order parameter of each sample was calculated, it was revealed that the order parameter of the dye molecule in Sample 3-2 was reduced as compared with the sample of Comparative Example 1.

Further, for the sample 3-1, the light intensity at which the first interference fringe appeared was measured using a beam profiler, and the threshold value of the light intensity of the sample 3-1 was examined in detail, and 4.3 W / cm. ² .

Next, in order to quantitatively evaluate the decrease in the orientation regulating force due to the increase in viscosity, two glass substrates with ITO electrodes were prepared, and a homogeneous cell (the sample of Example 3) was prepared using the polymerization sample. 3-3) was produced.
For Sample 3-3, the change in the amount of transmitted light of the probe light was measured every 1 ms from immediately after the voltage application was stopped until it returned to the initial state. As a result, when the relaxation times were compared, it was found that in Sample 3-3 containing the polymer-stabilized liquid crystal, the relaxation time was remarkably increased, and the alignment regulating force in the cell was decreased as the viscosity increased. .

〔Example〕
100/0 (Comparative Example 1) in a molar ratio of the compound represented by the above formula (II) and the acrylate monomer (A4CB) represented by the above formula (III) and having a cyanobiphenyl skeleton as a polymerization site, Mixing to become 98/2, 96/4, 94/6, 93/7, 92/8, 91/9, 90/10, 89/11, 87/13, composition (I-1) to (I-10) was prepared.
In the compositions (I-1) to (I-10), 0.1 mol% of the photoresponsive substance (oligothiophene TR5, manufactured by Merck & Co., Inc.) represented by the above formula (IV), and absorption only in the ultraviolet region. A photopolymerization initiator (trade name: Irgacure 651, manufactured by Nagase Sangyo Co., Ltd.) 0.5 mol% was added to prepare compositions (I-11) to (I-20).

Subsequently, the two glass substrates which performed the vertical alignment process with the silane coupling agent were bonded together, and the glass cell of thickness (cell gap) 100 micrometers was produced.
Next, the prepared compositions (I-11) to (I-20) were sealed in the glass cell (between two glass substrates) and irradiated with light at room temperature (25 ° C.).
The light irradiation was performed by taking out a bright line with a wavelength of 366 nm of a high-pressure mercury lamp with a filter and irradiating it with light having a light intensity of 1.0 mW / cm ² for 1 hour.
After light irradiation, the sample was gradually cooled from 70 ° C. to room temperature (25 ° C.) to obtain Samples 4-1 to 4-10 of Experimental Examples.

 Samples 4-1 to 4-10 were subjected to measurement of photoresponse behavior in the same manner as in Example 1. The results are shown in FIGS. FIG. 2 is a graph showing the relationship between the intensity of laser light (light intensity) and the number of interference fringes. FIG. 3 is a graph showing the relationship between the content of A4CB and the light intensity (light intensity threshold) at which the number of interference fringes rapidly increases. FIG. 4 is a graph showing the relationship between the content of A4CB and the maximum number of interference fringes.

From the results shown in FIGS. 2 and 4, it was found that the number of interference fringes is changed by changing the content of A4CB. That is, it has been found that the light intensity threshold at which the compositions (I-11) to (I-20) are oriented changes by changing the content of A4CB.
From the results of FIG. 3, it was found that the light intensity threshold at which the compositions (I-11) to (I-20) are oriented tends to be lowered as the A4CB content increases.
Further, from the result of FIG. 4, it was found that the number of interference fringes increases as the content of A4CB increases.

 From the above results, by using the polymer-stabilized liquid crystal, the samples of Examples 1 to 3 were able to reduce the light intensity threshold as compared with the sample of Comparative Example 1. In addition, by increasing the thickness of the vertically aligned molecules and weakening the initial alignment regulation force, the samples of Examples 1 to 3 have a lower light intensity threshold than the sample of Comparative Example 1. I was able to. Further, the samples of Examples 1 to 3 are compared with the sample of Comparative Example 1 by tilting the sample slightly with respect to the direction parallel to the plane of polarization of incident light and tilting the initial orientation of the dye with respect to the electric field. As a result, the threshold of light intensity could be reduced. Moreover, when these factors were multiplied, the samples of Examples 1 to 3 were able to further reduce the light intensity threshold as compared with the sample of Comparative Example 1.

 The present invention can be used, for example, as a liquid crystal display element and a manufacturing method thereof.

DESCRIPTION OF SYMBOLS 10 ... Liquid crystal display element 11, 12, ... Substrate, 13 ... Photoresponsive substance, 14 ... Anisotropic molecule, 15 ... Photoresponsive composition.

Claims (14)

 The photoresponsive composition is aligned by irradiating a photoresponsive composition containing a photoresponsive material having a threshold value in response light intensity and an anisotropic molecule with light having a light intensity equal to or greater than the threshold value. An optical element characterized by comprising:  The optical element according to claim 1, wherein the photoresponsive composition further contains an oligomer and / or a polymer.  The photoresponsive substance is an anisotropic substance that does not cause a photochemical reaction. By irradiating light having a light intensity equal to or higher than the threshold, the major axis direction of the photoresponsive substance is changed to the vibration direction of light. The optical element according to claim 1, which is oriented parallel to the optical element. The optical element according to claim 1, wherein the light intensity threshold is 10 W / cm ² or less.  The optical element according to claim 2, wherein the total content of the oligomer and / or polymer in the photoresponsive composition is 2 mol% or more and 13 mol% or less.  The optical element according to claim 1, wherein a thickness of the layer containing the photoresponsive composition is 3 μm or more. A layer containing the photoresponsive composition between the first substrate and the second substrate;
The photoresponsive composition is oriented parallel to the first substrate surface on the first substrate side, and perpendicular to the second substrate surface on the second substrate side. The optical element according to claim 1.  By irradiating a photoresponsive composition containing a photoresponsive substance having a threshold value in response light intensity and an anisotropic molecule with light having a light intensity equal to or higher than the threshold value, the photoresponsive composition is obtained. A method for producing an optical element, characterized by being oriented.  The method for producing an optical element according to claim 8, further comprising an oligomer and / or a polymer in the photoresponsive composition.  The photoresponsive substance is an anisotropic substance that does not cause a photochemical reaction, and the long axis direction of the photoresponsive substance is changed to a light oscillation direction by irradiating light having a light intensity equal to or greater than the threshold value. The method for producing an optical element according to claim 8, wherein the optical element is oriented parallel to the optical element.  The optical element according to any one of claims 8 to 10, wherein the light applied to the photoresponsive composition is applied at an angle with respect to a normal direction of a layer containing the photoresponsive composition. Manufacturing method.  The method for producing an optical element according to claim 11, wherein the angle is 15 degrees or less with respect to a normal line direction of the layer containing the photoresponsive composition.  The photoresponsive composition is sandwiched between a first substrate and a second substrate, and the photoresponsive composition is oriented parallel to the first substrate surface on the first substrate side. The light responsive composition is irradiated with light having a light intensity equal to or greater than the threshold value after being oriented perpendicularly to the second substrate surface on the second substrate side. The manufacturing method of the optical element of any one.  An optical element comprising a photoresponsive composition containing a photoresponsive substance having a threshold in response light intensity and an anisotropic molecule, wherein the photoresponsive composition is oriented.

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