JP2007045963A - Composition for polymer dispersion type liquid crystal-displaying element and polymer dispersion type liquid crystal-displaying element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a composition for a polymer dispersion type liquid crystal-displaying element, excellent in a low driving electric voltage characteristics in a low temperature region, having a high electric voltage-holding rate and capable of being driven by an active element, and a polymer dispersion type liquid crystal-displaying element. <P>SOLUTION: This composition for a polymer dispersion type liquid crystal-displaying element contains a compound selected from a group of compounds expressed by general formulae (I-a1), (I-a2) and (I-a3), and also a compound expressed by general formula (II-b) and a polymerization initiator. The polymer dispersion type liquid crystal-displaying element by using the composition is provided. The liquid crystal-displaying element is provided by having a wide operational temperature range, excellent in scattering characteristics, also having their small changes over time and excellent in heat resistance and light fastness, and is very practical as the display utilizing the light scattering. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a composition useful for a polymer dispersed liquid crystal display device that can be driven in a wide temperature range, and a polymer dispersed liquid crystal display device using the composition.

Since the polymer dispersion type liquid crystal display element does not require a polarizing plate, it has a merit that a bright display can be realized compared with a liquid crystal display element of TN, STN, IPS or VA mode using a conventional polarizing plate. Since this configuration is also simple, it is applied to optical shutter applications such as light control glass as seen in Non-Patent Document 1. In addition, in order to realize high-definition display, as seen in Non-Patent Document 2, application to a projector application combined with an active drive element is also being studied. Furthermore, taking advantage of the fact that bright display can be realized, it is also expected to be applied to a reflective display for mobile use assuming outdoor use.

  In order to apply the polymer-dispersed liquid crystal display element to a display for mobile use, high reliability is required, a low operating voltage is required, and these must be achieved in a wide range of temperatures. As a low-voltage driving technique, Patent Document 1 discloses a technique in which a transparent solid substance is formed in a three-dimensional network structure in a liquid crystal continuous phase, but the operating voltage at 25 ° C. is as high as 7.3 V, The operating voltage at -20 ℃ is 10V or more.

  Patent Document 2, Patent Document 3, and Patent Document 4 disclose a technique for achieving a low driving voltage by using a side chain type radically polymerizable compound. In the temperature range of 20 ° C., the driving voltage is 10 V or more, and it cannot be applied to mobile displays.

  Patent Document 5 and Non-Patent Document 3 describe a technique for reducing the temperature dependence of the drive voltage, but the drive voltage is as high as 7 V or more, and more in the temperature range of -10 to -20 ° C. The driving voltage was high.

  As described above, in the polymer dispersion type liquid crystal display element, it is difficult to lower the voltage in the low temperature region, and the low voltage driving in the low temperature region of −10 ° C. or less has not been achieved. Therefore, there has been a demand for low-voltage operation in a lower temperature range. In addition, since the temperature dependency of the driving voltage in the low temperature region is large, a composition capable of reducing the temperature dependency and a device having a small temperature dependency have been demanded.

JP-A-1-198725 (Claim 1) JP-A-6-32761 (pages 9 to 12) JP 11-29527 A (pages 19 to 22) JP 2002-293828 A (pages 17 to 18) JP-A-9-329781 (pages 6 to 16) Industrial Materials March 1992 (24 pages) 1991 Society for Information Display (SID) International Symposium Digest of Technical Paper (page 251) Display International Workshop (IDW) '97 Digest, 1997 (33 pages)

  An object of the present invention is to provide a polymer-dispersed liquid crystal display element composition and a polymer-dispersed liquid crystal display element that are excellent in low drive voltage characteristics in a low temperature range. In particular, it is intended to provide a polymer-dispersed liquid crystal display element composition and a polymer-dispersed liquid crystal display element that are excellent in low driving voltage characteristics in a low temperature region and have low temperature dependence in mobile applications.

In order to solve the above-mentioned problems, the present invention has studied the combinations of various liquid crystal compositions and radical polymerizable compounds, and as a result, has come to solve the problems.
That is, general formula (I-a1), general formula (I-a2), and general formula (I-a3)

(Wherein R ⁴¹ , R ⁴² and R ⁴³ each independently represents an alkyl group having 1 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms, and is present in the alkyl group or alkenyl group. One or more CH ₂ groups may be substituted with oxygen atoms, assuming that the oxygen atoms are not directly bonded to each other,
A ¹¹ represents a 1,4-cyclohexylene group or a 1,3-dioxane-2,5-diyl group,
A ¹² and A ¹³ each independently represents a 1,4-phenylene group or a 1,4-cyclohexylene group, and the 1,4-phenylene group is unsubstituted or has one or two substituents It can have the above fluorine atom, chlorine atom, methyl group or trifluoromethyl group or trifluoromethoxy group,
X ^{1 to} X ¹⁰ each independently represent a hydrogen atom, a fluorine atom, a chlorine atom, a trifluoromethyl group or a trifluoromethoxy group,
Z ¹¹ to Z ¹⁴ each independently represent a single _{bond, -COO -, - CH 2 -CH} 2 - , or -CF ₂ O-,
n ¹ , n ² , n ³ and n ⁴ represent 0 or 1; )
Containing at least one kind from the compound group represented by the general formula (II-b)

(In the formula, B ⁵ , B ⁶ and B ⁷ each independently represent a single bond or an alkylene group having 1 to 19 carbon atoms, and the alkylene group is unsubstituted or has one or two substituents. It may have the above fluorine atom, methyl group, ethyl group, and one or two or more CH ₂ groups present in the alkylene group are oxygen atoms as those in which oxygen atoms are not directly bonded to each other, -CO-, -COO-, -OCO-, 1,4-phenylene group, pyridine-2,5-diyl group, pyrimidine-2,5-diyl group, 1,3-dioxane-2,5-diyl group, 1,4-cyclohexylene group, bicyclo [2.2.2] octane-1,4-diyl group or 3,3′-spirobicyclobutylene may be substituted, and the 1,4-phenylene group is unsubstituted 1 or 2 or more fluorine atoms, chlorine atoms, methyl groups or trifluoromethyl groups or trifluoromethoxy as a substituent At least one CH ₂ group in the alkylene group may have the general formula (II-a)

（式中、B¹及びB²はそれぞれ独立して炭素数2から30のアルキル基を表し、該アルキル基は非置換であるか又は置換基として１個又は２個以上のフッ素原子を有していても良く、該アルキル基中に存在する１個又は２個以上のCH₂基は、酸素原子が相互に直接結合しないものとして酸素原子、−CO−、−COO−、−OCO−、1,4-フェニレン基、ピリジン-2,5-ジイル基、ピリミジン-2,5-ジイル基、1,3-ジオキサン-2,5-ジイル基、1,4-シクロヘキシレン基、ビシクロ[2.2.2]オクタン-1,4-ジイル基又は3,3'-スピロビシクロブチレンで置換されていても良い。ただし、B¹及びB²は共に非重合性基である。）
で置換され、B⁵、B⁶及びB⁷の炭素原子数の合計は5以上であり、

(In the formula, each of B ¹ and B ² independently represents an alkyl group having 2 to 30 carbon atoms, and the alkyl group is unsubstituted or has one or more fluorine atoms as a substituent. 1 or 2 or more CH ₂ groups present in the alkyl group may be oxygen atoms, —CO—, —COO—, —OCO—, 1 on the assumption that oxygen atoms are not directly bonded to each other. , 4-phenylene group, pyridine-2,5-diyl group, pyrimidine-2,5-diyl group, 1,3-dioxane-2,5-diyl group, 1,4-cyclohexylene group, bicyclo [2.2.2 It may be substituted with an octane-1,4-diyl group or 3,3′-spirobicyclobutylene, provided that B ¹ and B ² are both non-polymerizable groups.
And the total number of carbon atoms of B ⁵ , B ⁶ and B ⁷ is 5 or more,

B ³ and B ⁴ each independently represent a hydrogen atom or a methyl group,
m and n each independently represent 1, 2 or 3. )
A polymer-dispersed liquid crystal device composition comprising a polymerizable compound represented by formula (1) and further containing a polymerization initiator, and a polymer-dispersed liquid crystal device comprising the composition as a constituent member provide.

  With the polymer dispersed liquid crystal display element composition and polymer dispersed liquid crystal display element of the present invention, a liquid crystal display element excellent in low drive voltage characteristics in a low temperature range could be obtained. In addition, the composition and device have a wide operating temperature range, are excellent in scattering characteristics, have little change over time, have excellent heat resistance, and light resistance, and are mobile devices that utilize light scattering. It is very practical for reflective displays for applications.

An example of the present invention will be described below. In the composition for a polymer dispersed liquid crystal display element of the present invention, the radically polymerizable compound as the second component is polymerized by active energy rays such as heat or ultraviolet rays, and the liquid crystal composition as the first component is associated therewith. It is used for the purpose of causing separation and obtaining a polymer-dispersed liquid crystal display element comprising a transparent polymer substance and a liquid crystal composition.
Japanese Patent Laid-Open No. 6-22220 / 1990 discloses the relationship of the following formula as a description of the driving voltage of the polymer dispersion type liquid crystal display element.

（Ｖthはしきい値電圧を表わし、¹Kii及び²Kiiは弾性定数を表わし、ｉは１、２又は３を表わし、Δεは誘電率異方性を表わし、＜ｒ＞は透明性高分子物質界面の平均空隙間隔を表わし、Ａは液晶組成物に対する透明性高分子物質のアンカリングエネルギーを表わし、ｄは透明性電極を有する基板間の距離を表わす。）

(Vth represents threshold voltage, ¹ Kii and ² Kii represent elastic constants, i represents 1, 2 or 3, Δε represents dielectric anisotropy, and <r> represents a transparent polymer substance. (Indicates the average gap distance of the interface, A indicates the anchoring energy of the transparent polymer substance with respect to the liquid crystal composition, and d indicates the distance between the substrates having transparent electrodes.)

According to this, the driving voltage of the polymer-dispersed liquid crystal display element includes the average gap distance at the interface of the transparent polymer material, the distance between the substrates, the elastic constant / dielectric anisotropy of the liquid crystal composition, and the liquid crystal composition. It is determined by the anchoring energy between transparent polymer materials. The parameters that change with temperature are the elastic constant and dielectric anisotropy of the liquid crystal composition and the anchoring energy between the liquid crystal composition and the transparent polymer substance. Therefore, the factors that increase the driving voltage in the low temperature range are the elastic constant of the liquid crystal composition and the anchoring energy between the liquid crystal composition and the transparent polymer substance. In particular, when the anchoring energy rises at a low temperature, the driving voltage increases greatly, making it difficult to use in mobile applications. Therefore, in order to achieve low voltage driving in a low temperature range, in addition to having high dielectric anisotropy, a liquid crystal composition excellent in nematic stability in a wide liquid crystal temperature range, particularly in a low temperature range, must be used. In addition, a combination having a low anchoring energy between the liquid crystal composition and the transparent polymer material in a low temperature region must be found.
Therefore, as a result of examining combinations of various liquid crystal compositions and polymerizable compounds, the compounds represented by general formula (I-a1), general formula (I-a2), and general formula (I-a3) A transparent polymer material obtained by polymerizing a composition containing one or more types and a polymerizable compound represented by the general formula (II-b) using a polymerization initiator is a liquid crystal composition in a low temperature range. We found that the anchoring energy between the object and the transparent polymer material is small.

The compounds represented by general formula (I-a1), general formula (I-a2), and general formula (I-a3) are liquid crystal compositions in a light control layer formed in a polymer-dispersed liquid crystal display device. Is a compound that forms The liquid crystal composition preferably has not only high dielectric anisotropy and a wide liquid crystal temperature range, but also high refractive index anisotropy and low viscosity. Furthermore, it is also a preferable condition that the liquid crystal composition is excellent in heat resistance and light resistance. In particular, in order to realize a low driving voltage in a low temperature region, it is an essential condition to have a high dielectric anisotropy. The compounds represented by general formula (I-a1), general formula (I-a2), and general formula (I-a3) have high dielectric anisotropy and high compatibility, so they have a wide liquid crystal temperature range, especially at low temperatures. It is a compound with excellent nematic stability in the region.
In the general formula (I-a1), general formula (I-a2), and general formula (I-a3), R ⁴¹ , R ^42, and R ⁴³ are each an alkyl group having 1 to 5 carbon atoms or 2 carbon atoms. To 6 alkenyl groups (one or more CH ₂ groups present in the alkyl group or alkenyl group may be substituted with an oxygen atom, assuming that O atoms are not directly bonded to each other). Wherein the alkenyl group is of the formula (Va)

(The structural formula is assumed to be connected to the ring directly or through an oxygen atom at the right end), and an alkyl group having 1 to 5 carbon atoms is more preferable.
A ¹¹ in the general formula (I-a1) is preferably a 1,4-cyclohexylene group,
Z ¹¹ is preferably a single bond,
Z ¹² is preferably a single bond or —CF ₂ O—,
X ¹ and X ² are preferably a hydrogen atom or a fluorine atom.
Z ¹³ in the general formula (I-a2) is preferably a single bond,
Z ¹⁴ is preferably a single bond, -COO- or -CF ₂ O-,
X ³ , X ⁴ , X ⁵ and X ⁶ are preferably a hydrogen atom or a fluorine atom.
In general formula (I-a3), n ¹³ and n ¹⁴ are both 0, n ¹³ is 0 and n ¹⁴ is 1, or n ¹³ is 1 and n ¹⁴ is 0,

When both n ¹³ and n ¹⁴ are 0, X ⁹ and X ¹⁰ are preferably a hydrogen atom or a fluorine atom,
When n ¹³ is 0 and n ¹⁴ is 1, X ⁹ and X ¹⁰ are preferably a hydrogen atom or a fluorine atom,
X ⁷ and X ⁸ are preferably hydrogen atoms,
When n ¹³ is 1 and n ¹⁴ is 0, X ⁹ and X ¹⁰ are preferably a hydrogen atom or a fluorine atom.
Specifically, as the general formula (I-a1), compounds represented by the general formula (V-1) to the general formula (V-12) are preferable,

(In the formula, R ¹¹ represents an alkyl group having 1 to 5 carbon atoms or an alkenyl group represented by the formula (Va).)
As general formula (I-a2), compounds represented by general formula (VI-1) to general formula (VI-44) are preferable,

（式中、R¹¹は炭素原子数1から5のアルキル基、又は式(V-a)で表されるアルケニル基を表す。）

(In the formula, R ¹¹ represents an alkyl group having 1 to 5 carbon atoms or an alkenyl group represented by the formula (Va).)

（式中、R¹¹は炭素原子数1から5のアルキル基、又は式(V-a)で表されるアルケニル基を表す。）
一般式（I-a3）としては、一般式（VII-1）から一般式（VII-12）で表される化合物が好ましい。

(In the formula, R ¹¹ represents an alkyl group having 1 to 5 carbon atoms or an alkenyl group represented by the formula (Va).)
As the general formula (I-a3), compounds represented by the general formulas (VII-1) to (VII-12) are preferable.

(In the formula, R ¹¹ represents an alkyl group having 1 to 5 carbon atoms or an alkenyl group represented by the formula (Va).)
Furthermore, it is preferable to contain at least two kinds of compounds represented by the general formula (I-a1), the general formula (I-a2), and the general formula (I-a3). ) And general formula (I-a3) are more preferable.
In addition to the compounds of general formula (I-a1), general formula (I-a2), and general formula (I-a3) in order to obtain further expansion of liquid crystal temperature range, high refractive index anisotropy and low viscosity It is also preferable to contain a compound represented by general formula (III-a) or general formula (IV-a).
The compound represented by the general formula (III-a) preferably contains at least one compound from the group of compounds represented by the general formula (III-b) and the general formula (III-c). It is more preferable to contain the compound represented by (III-c).

(Wherein R ¹⁵ , R ¹⁶ , R ¹⁷ , and R ¹⁸ are each independently an alkyl group having 1 to 5 carbon atoms or an alkenyl group having 2 to 6 carbon atoms (in the alkyl group or alkenyl group, One or more CH ₂ groups present may be substituted with oxygen atoms as O atoms are not directly bonded to each other)
A ¹⁵ , A ¹⁶ , A ¹⁷ and A ¹⁸ are each independently a 1,4-phenylene group or a 1,4-cyclohexylene group (the 1,4-phenylene group is one or more as a substituent). Can have a fluorine atom or a methyl group)
Z ¹⁵ , Z ¹⁶ and Z ¹⁷ represent a single bond, —COO— or —CH ₂ CH ₂ —,
X ¹⁵ to X ²⁰ is a hydrogen atom, a fluorine atom, a methyl group. )
Specifically, as the general formula (III-b), compounds represented by the general formula (III-1) to the general formula (III-6) are preferable,

(Wherein R ²¹ and R ²² are an alkyl group having 1 to 5 carbon atoms or an alkenyl group having 2 to 6 carbon atoms (one or two or more CH ₂ present in the alkyl group or alkenyl group). The group may be substituted with an oxygen atom, assuming that the O atoms are not directly bonded to each other)
X ^{21 to} X ²⁹ represent a hydrogen atom, a fluorine atom, or a methyl group. )
As general formula (III-c), compounds represented by general formula (J-51) to general formula (J-60) are preferable.

(In the formula, R ³⁵ and R ³⁶ are each independently an alkyl group having 1 to 5 carbon atoms or an alkenyl group having 2 to 6 carbon atoms (one or two present in the alkyl group or alkenyl group). The above CH ₂ group may be substituted with an oxygen atom as O atoms are not directly bonded to each other.
X ⁸¹ to X ⁸⁶ each independently represent a hydrogen atom, a fluorine atom, or a methyl group. )
Furthermore, it is also preferable to contain a compound represented by the general formula (IV-a) in order to obtain a high dielectric constant and expansion of the liquid crystal temperature region.

R ^{5 in the} general formula (IV-a) is an alkyl group having 1 to 5 carbon atoms or an alkenyl group having 2 to 6 carbon atoms (one or two or more present in the alkyl group or alkenyl group). CH ₂ group may be substituted with an oxygen atom as O atoms are not directly bonded to each other.
A ⁶ , A ⁷ , and A ⁸ include 1,4-phenylene group or 1,4-cyclohexylene group (the 1,4-phenylene group has one or more fluorine atoms as a substituent). Is preferred)
X ¹³ is preferably a fluorine atom,
Specifically, compounds represented by general formulas (IV-1) to (IV-6) are preferable.

(In the formula, R ³³ represents an alkyl group having 1 to 5 carbon atoms or an alkenyl group represented by the formula (Va), and X ^{71 to} X ⁷⁵ each represents a hydrogen atom or a fluorine atom.)
When a liquid crystal composition is obtained by combining a compound group represented by general formula (I-a1), general formula (I-a2), and general formula (I-a3) with general formula (III-a), The ratio of the compound group represented by the formula (I-a1), the general formula (I-a2), and the general formula (I-a3) is 20 to 70% by mass, and the ratio of the general formula (III-a) is 30 to The combination of 80% by mass is preferable, and the ratio of the compound groups represented by the general formula (I-a1), general formula (I-a2), and general formula (I-a3) is 30 to 60% by mass, It is more preferable that the ratio of the general formula (III-a) is 40 to 70% by mass, which is represented by the general formula (I-a1), the general formula (I-a2), and the general formula (I-a3). When a liquid crystal composition is obtained by combining a compound group represented by formula (III-a), a compound represented by formula (IV-a), a general formula (I-a1), The ratio of the compound group represented by the formula (I-a2) and the general formula (I-a3) is 30 to 60% by mass, and the general formula (III-a) It is preferable that the ratio of the compound represented by the general formula (IV-a) is 30 to 60% by mass.
These liquid crystal compositions may be subjected to a purification treatment with silica, alumina or the like for the purpose of removing impurities or the like or further increasing the specific resistance value. The specific resistance value is preferably 10 ¹⁰ Ω · cm or more, and more preferably 10 ¹¹ Ω · cm or more.
Furthermore, dopants such as chiral compounds and dyes can be added to the liquid crystal composition according to the purpose.

  The polymerizable compound is a compound that forms a transparent polymer substance in the light control layer formed in the polymer dispersion type liquid crystal display element, and is polymerizable by polymerizing this compound with heat or active energy rays. A desired transparent polymer substance can be obtained by causing phase separation between the compound and the low-molecular liquid crystal composition and forming a fine phase separation structure of submicron order. In order to achieve a low driving voltage in a low temperature region of a polymer dispersion type liquid crystal display element, it is not sufficient to achieve a wide liquid crystal temperature range of the liquid crystal composition. A combination having a low anchoring energy between the liquid crystal composition and the transparent polymer material must be found. The anchoring energy greatly depends on the side chain structure and the main chain structure of the transparent polymer substance, and also greatly depends on the molecular mobility with respect to heat of the side chain and the main chain. For example, it is possible to control the surface energy of the transparent polymer substance by controlling the length and interval of the side chain, and in order to realize a low voltage, it is preferable that the surface energy is comparable to that of the liquid crystal composition. . In addition, since the molecular mobility of the side chain and the main chain with respect to heat decreases, specifically, when the glass transition temperature (Tg) or lower of the transparent polymer material is lowered, the driving voltage increases greatly. The glass transition temperature (Tg) is preferably low, and is an important factor for achieving a low voltage particularly in a low temperature range. Specifically, Tg can be lowered by increasing the main chain length of the transparent polymer substance to increase the distance between crosslinks, or by introducing a methyl group or an ethyl group into a part of the main chain. Such a transparent polymer substance can be obtained from a polymerizable compound represented by the general formula (II-b). Due to the presence of the partial structure represented by the general formula (II-a) present in this compound, the surface energy of the transparent polymer substance can be controlled, and low voltage driving in a low temperature range is realized.

B ⁵ , B ⁶ and B ^{7 in the} general formula (II-b) are preferably a combination of alkylene groups in which the total number of carbon atoms of B ⁵ , B ⁶ and B ⁷ is 5 to 31, A combination of alkylene groups with a total of 5 to 20 is more preferable, a combination of alkylene groups with a total number of carbon atoms of 10 to 15 is more preferable, and 2 or more and 6 or less CH ₂ groups of the alkylene groups are oxygen An alkylene group substituted with an atom or an ester group is preferable, and two CH ₂ groups are more preferably substituted with an oxygen atom or an ester group. M and n are preferably 1, an alkylene group having 5 to 15 carbon atoms in which m and n are 1 and the total number of B ⁵ , B ⁶ and B ⁷ carbon atoms, and two CH ₂ groups of the alkylene group are oxygen More preferably, it is substituted with an atom or an ester group.
The number of substituents of the general formula (II-a) present in B ⁵ , B ⁶ and B ⁷ is preferably 2 to 4, more preferably 2. B ¹ may be linear or branched, but in the case of linear, at least one is preferably an alkyl group having 5 to 16 carbon atoms, more preferably 10 to 14 ( One or two or more CH ₂ groups present in the alkyl group may be substituted with oxygen atoms, —CO—, —COO—, —OCO—, as oxygen atoms are not directly bonded to each other. good). It is even more preferable that 1 to 5 CH ₂ groups in the alkyl group are substituted with an oxygen atom or —COO—.

In the case of having a branched chain, the main chain in at least one branched chain is preferably an alkyl group having 5 to 16 carbon atoms, more preferably 10 to 14 (one existing in the alkyl group) Alternatively, two or more CH ₂ groups may be substituted with oxygen atoms, —CO—, —COO—, —OCO—, in which oxygen atoms are not directly bonded to each other). It is even more preferable that 1 to 8 CH ₂ groups in the alkyl group are substituted with an oxygen atom or —COO—.
B ² is preferably an alkyl group having 2 to 5 carbon atoms.
B ³ and B ⁴ are preferably hydrogen atoms.
Furthermore, as the polymerizable compound, a compound represented by the general formula (II-c)

(In the formula, B ⁸ , B ⁹ and B ¹⁰ each independently represents a single bond or an alkylene group having 1 to 19 carbon atoms, and one or more CH ₂ groups present in the alkylene group are The oxygen atoms may be substituted with oxygen atoms, -CO-, -COO- or -OCO- as those in which the oxygen atoms are not directly bonded to each other, but the total number of carbon atoms of B ⁸ , B ⁹ and B ¹⁰ is 3 29 and
B ¹¹ and B ¹³ each independently represent an alkyl group having 2 to 25 carbon atoms, and one or more CH ₂ groups present in the alkyl group are those in which oxygen atoms are not directly bonded to each other. May be substituted with an oxygen atom, -CO-, -COO- or -OCO-,
B ¹² and B ¹⁴ are each independently preferably a hydrogen atom or an alkyl group having 2 to 5 carbon atoms. In the general formula (II-c), the total number of carbon atoms of B ⁸ , B ⁹ and B ¹⁰ is 5 29, and B ¹¹ and B ¹³ are alkyl groups having 5 to 25 carbon atoms (one or more CH ₂ groups present in the alkyl group are oxygen atoms on the assumption that oxygen atoms are not directly bonded to each other) atom, -CO -, -. the COO- or may be substituted with -OCO-) and is, more preferably those B ¹² and B ¹⁴ is an alkyl group having 2 to 5 carbon atoms,

In the general formula (II-c), the total number of carbon atoms of B ⁸ , B ⁹ and B ¹⁰ is 8 to 25, and B ¹¹ and B ¹³ are linear alkyl groups having 8 to 16 carbon atoms. , One CH ² group in the alkyl group is substituted with an oxygen atom or —COO—, or B ¹¹ and B ¹³ are branched alkyl groups, and the number of carbon atoms in the main chain of the alkyl group Is an alkyl group having 8 to 16; one CH ² group in the alkyl group is substituted with an oxygen atom or —COO—, and B ¹² and B ¹⁴ are alkyl groups having 2 to 5 carbon atoms. Some are more preferred.

  Specifically, compounds of general formula (II-d), general formula (II-e), and general formula (II-f) are preferable.

(Wherein p and r represent 0 or 1, q represents 2 to 20, s and t represent 0, 1, 2 or 3, and B ²¹ and B ²² have 6 to 14 carbon atoms. A linear alkyl group (1 to 4 CH ₂ groups in the alkyl group may be substituted with oxygen atoms), or a main chain having 6 to 14 carbon atoms and 7 to 23 carbon atoms Represents a branched alkyl group (1 to 7 CH ₂ groups in the alkyl group may be substituted with an oxygen atom), and B ²³ and B ²⁴ represent an alkyl group having 2 to 5 carbon atoms; Y ¹ and Y ² each independently represent a hydrogen atom, a methyl group or an ethyl group.)
As the polymerizable compound that forms the transparent polymer substance of the polymer dispersed liquid crystal, one or more of the above polyfunctional polymerizable compounds can be used, and it can be used in combination with the monofunctional polymerizable compound. .
In consideration of the condition that the radical polymerizable compound does not volatilize due to the vacuum injection condition during the manufacturing process of the polymer dispersion type liquid crystal display element, the molecular weight of the polymerizable compound is preferably 300 to 1500, and preferably 500 to 1000. More preferred. Furthermore, it is preferable that the surface energy of the transparent polymer material obtained by curing a polymerizable compound is 40 mN / m ² to 20, and more preferably a 37 mN / m ² to 27.
These polymerizable compounds may be subjected to a purification treatment with silica, alumina or the like for the purpose of removing impurities or increasing the high specific resistance value. The specific resistance value is preferably 10 ⁸ Ω · cm or more, and more preferably 10 ⁹ Ω · cm or more.

  As a polymerization method, radical polymerization, anionic polymerization, cationic polymerization, and the like can be used, but polymerization is preferably performed by radical polymerization.

As the radical polymerization initiator, a thermal polymerization initiator or a photopolymerization initiator can be used, but a photopolymerization initiator is preferable. Specifically, the following compounds are preferable.
Diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, benzyldimethyl ketal, 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropan-1-one, 4- ( 2-hydroxyethoxy) phenyl- (2-hydroxy-2-propyl) ketone, 1-hydroxycyclohexyl-phenylketone, 2-methyl-2-morpholino (4-thiomethylphenyl) propan-1-one, 2-benzyl- Acetophenone series such as 2-dimethylamino-1- (4-morpholinophenyl) -butanone;
Benzoins such as benzoin, benzoin isopropyl ether and benzoin isobutyl ether; acylphosphine oxides such as 2,4,6-trimethylbenzoyldiphenylphosphine oxide; benzyl and methylphenylglyoxyesters;
Benzophenone, methyl o-benzoylbenzoate, 4-phenylbenzophenone, 4,4'-dichlorobenzophenone, hydroxybenzophenone, 4-benzoyl-4'-methyl-diphenyl sulfide, acrylated benzophenone, 3,3 ', 4,4' -Benzophenone series such as tetra (t-butylperoxycarbonyl) benzophenone, 3,3'-dimethyl-4-methoxybenzophenone;
Thioxanthone systems such as 2-isopropylthioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2,4-dichlorothioxanthone;
Aminobenzophenone series such as Michler's ketone and 4,4′-diethylaminobenzophenone;
10-butyl-2-chloroacridone, 2-ethylanthraquinone, 9,10-phenanthrenequinone, camphorquinone and the like are preferable.
Among these, benzoin isopropyl ether and benzyl dimethyl ketal are more preferable.

  59 to 89% by mass of a liquid crystal composition comprising a compound selected from the group of compounds represented by general formula (I-a1), general formula (I-a2), and general formula (I-a3), It is preferable that the polymerizable compound represented by (II-b) is contained in an amount of 10 to 40% by weight and a polymerization initiator is contained in an amount of 0.1 to 2% by mass. The compounds represented by the general formulas (I-a1) and (I-a2) ) And a liquid crystal composition composed of a compound selected from the group of compounds represented by formula (I-a3) is contained in an amount of 69 to 80% by mass, and a polymerizable compound represented by formula (II-b) is 19 To 30% by mass, and more preferably 0.1 to 2% by mass of the polymerization initiator.

A method for manufacturing a polymer-dispersed liquid crystal display element will be described. The polymer-dispersed liquid crystal display element of the present invention has a composition for polymer-dispersed liquid crystal display elements of the present invention sandwiched between two substrates, at least one of which is transparent, and then heat or active energy rays. It is obtained by polymerizing the polymerizable compound by irradiation and inducing phase separation from the liquid crystal composition to form a light control layer composed of the liquid crystal composition and a transparent polymer substance.
The two substrates can be made of a transparent material having flexibility such as glass and plastic, and one of them can be an opaque material such as silicon. Functions such as light absorption, specular reflection, diffuse reflection, retroreflection, and hologram reflection can also be added. The glass substrate surface can be coated with polyimide or the like.
A spacer for maintaining a gap can be interposed between the two substrates, as in a known liquid crystal device. The thickness between the substrates, that is, the thickness of the light control layer is preferably 2 to 50 μm, more preferably 3 to 30 μm, still more preferably 5 to 20 μm.

  As a method for sandwiching the polymer-dispersed liquid crystal display element composition between two substrates, a normal vacuum injection method, an ODF method, or the like can be used. At this time, the polymer-dispersed liquid crystal display element composition is preferably in a uniform isotropic state.

As a method for polymerizing the radically polymerizable compound, ultraviolet irradiation is suitable. As a lamp for generating ultraviolet rays, a metal halide lamp, a high-pressure mercury lamp, an ultra-high pressure mercury lamp, or the like can be used. Further, the wavelength of the ultraviolet rays to be irradiated is an absorption wavelength region of the photopolymerization initiator contained in the polymer-dispersed liquid crystal display element composition, and a wavelength that is not the absorption wavelength region of the contained liquid crystal composition. It is preferable to irradiate ultraviolet rays in the region, and specifically, it is preferable to cut and use ultraviolet rays of 330 nm or less using a metal halide lamp, high-pressure mercury lamp, or ultrahigh-pressure mercury lamp.
Intensity of ultraviolet light irradiation, can be appropriately adjusted to obtain a light control layer of interest is preferably 200 mW / cm ² from 1, 2 to 100 mW / cm ² is more preferable. The time for irradiation with ultraviolet rays is appropriately selected depending on the intensity of ultraviolet rays to be irradiated, but is preferably 10 to 600 seconds. More preferably, it is preferable to ultraviolet exposure so as to ^{1000mJ / cm 2 ~5000mJ / cm 2} .
The temperature at the time of ultraviolet irradiation is an important factor that determines the characteristics of the light control layer, but is preferably slightly higher than the isotropic-nematic transition point of the polymer dispersed liquid crystal display element composition. Specifically, the transition point +0.1 to 3 ° C. is preferable.

The light control layer in the polymer-dispersed liquid crystal display device manufactured by the above-described method or other methods has a structure in which the liquid crystal composition is confined in a capsule shape with a transparent polymer substance. It has a structure in which a three-dimensional network structure of a transparent polymer substance is formed in the continuous phase, or a structure in which both are mixed, but the three-dimensional structure of the transparent polymer substance in the continuous phase of the liquid crystal composition. A structure in which a network structure is formed is preferable, and a structure in which a three-dimensional network structure of a transparent polymer substance is formed in the continuous phase of the liquid crystal composition by ultraviolet irradiation is more preferable.
The average gap spacing of the network structure greatly affects the characteristics of the polymer dispersion type liquid crystal display element, and the average gap spacing is preferably 0.2 to 2 μm, more preferably 0.4 to 1.5 μm, and most preferably 0.5 to 1.0 μm.
The polymer-dispersed liquid crystal display element of the present invention is characterized by a low driving voltage at a low temperature, but V90 at a cell thickness of 10 μm is preferably 10.0 V or less, more preferably 7.0 V or less, and 5.0 Even more preferably, it is V or less.

EXAMPLES Hereinafter, although an Example is given and this invention is further explained in full detail, this invention is not limited to these Examples. Further, “%” in the compositions of the following examples and comparative examples means “mass%”.
The polymer dispersion type liquid crystal display elements in the examples were produced by the following method.
A composition for a polymer dispersion type liquid crystal display device comprising a liquid crystal composition, a polymerizable compound and a photopolymerization initiator was injected into a glass cell with ITO having a cell thickness of 10 μm by a vacuum injection method. At this time, the temperature in the vacuum injection apparatus was controlled so that the composition for the polymer-dispersed liquid crystal display element was always in a uniform state. The degree of vacuum was set to 2 pascals. After the injection, the glass cell was taken out and the inlet was sealed with a sealing agent 3026E (manufactured by ThreeBond Co., Ltd.). Then, a metal halide lamp adjusted so that the irradiation intensity through the UV cut filter UV-35 (manufactured by Toshiba Glass Co., Ltd.) was 20 mW / cm ² was irradiated for 120 seconds to obtain a polymer dispersed liquid crystal display device. .
Abbreviations and meanings of characteristics of liquid crystal compositions shown in the examples are as follows.

TN-I: Nematic phase-isotropic liquid phase transition temperature (℃)
T → N: Solid phase or smectic phase-nematic phase transition temperature (℃)
The liquid crystal temperature range (nematic liquid crystal temperature range) means from the solid phase or smectic phase-nematic phase transition temperature to the nematic phase-isotropic phase transition temperature unless otherwise specified.
Abbreviations and meanings of characteristics of the polymer dispersed liquid crystal display elements shown in the examples are as follows.
V90: Light transmittance (T100) when the transmittance of the polymer dispersed liquid crystal display element when no voltage is applied is 0% and the applied voltage is increased and the light transmittance hardly changes. The applied voltage value at which the light transmittance is 90%, where is 100%.

(Example 1)
A composition for a polymer dispersion type liquid crystal display device comprising 78% of a liquid crystal composition (A), 21.6% of a radical polymerizable compound (L) and 0.4% of a photopolymerization initiator Irgacure 651 (manufactured by Ciba Specialty Chemicals). And a polymer-dispersed liquid crystal display element was obtained by the method described above. The liquid crystal temperature range of the liquid crystal composition (A) is -40 to 72.7 ° C. V90 of this device is 3.7V at 25 ° C, 3.8V at 0 ° C, 3.9V at -10 ° C, 4.6V at -20 ° C there were.

(Example 2)
The liquid crystal composition (A) in Example 1 was changed to (B), and a polymer dispersion type liquid crystal display device was obtained in the same manner. The liquid crystal temperature range of the liquid crystal composition (B) is -45 to 76.7 ° C. V90 of this device is 2.9V at 25 ° C, 3.2V at 0 ° C, 3.6V at -10 ° C, 4.1V at -20 ° C there were.

(Example 3)
The liquid crystal composition (A) in Example 1 was changed to (C), and a polymer dispersion type liquid crystal display device was obtained in the same manner. The liquid crystal temperature range of the liquid crystal composition (C) is -41 to 76.5 ° C. V90 of this device is 3.6V at 25 ° C, 3.9V at 0 ° C, 4.1V at -10 ° C, 5.0V at -20 ° C there were.

(Example 4)
The liquid crystal composition (A) in Example 1 was changed to (D), and a polymer dispersion type liquid crystal display device was obtained in the same manner. The liquid crystal temperature range of the liquid crystal composition (D) is -35 to 77.0 ° C. V90 of this device is 4.5V at 25 ° C, 4.5V at 0 ° C, 4.5V at -10 ° C, 4.8V at -20 ° C there were.

(Example 5)
Liquid crystal composition (E) is 78%, radical polymerizable compound (L) is 17.3%, radical polymerizable compound (S) is 4.3%, photopolymerization initiator Irgacure 651 (manufactured by Ciba Specialty Chemicals) is from 0.4% A composition for a polymer dispersed liquid crystal display device was prepared, and a polymer dispersed liquid crystal display device was obtained by the above-described method. The liquid crystal temperature range of the liquid crystal composition (E) is -40 to 74.9 ° C. V90 of this element is 2.4V at 25 ° C, 3.0V at 0 ° C, 3.3V at -10 ° C, 3.7V at -20 ° C there were.

(Example 6)
The liquid crystal composition (A) in Example 1 was changed to (F), and a polymer dispersion type liquid crystal display device was obtained in the same manner. The liquid crystal temperature range of the liquid crystal composition (F) is -30 to 76.4 ° C. V90 of this device is 3.5V at 25 ° C, 4.1V at 0 ° C, 4.5V at -10 ° C, 4.8V at -20 ° C there were.

(Example 7)
The liquid crystal composition (A) in Example 1 was changed to (G), and a polymer dispersion type liquid crystal display device was obtained by the same method. The liquid crystal temperature range of the liquid crystal composition (G) is -35 to 74.5 ° C. V90 of this device is 4.5V at 25 ° C, 4.6V at 0 ° C, 4.5V at -10 ° C, 4.9V at -20 ° C there were.

(Example 8)
Liquid crystal composition (A) is 78%, radical polymerizable compound (M) is 17.6%, radical polymerizable compound (S) is 4.0%, photopolymerization initiator Irgacure 651 (manufactured by Ciba Specialty Chemicals) is from 0.4% A composition for a polymer dispersed liquid crystal display device was prepared, and a polymer dispersed liquid crystal display device was obtained by the above-described method. V90 of this element was 4.2V at 25 ° C, 4.4V at 0 ° C, 4.6V at -10 ° C, and 4.8V at -20 ° C.

(Example 9)
Liquid crystal composition (A) is 78%, radical polymerizable compound (M) is 17.6%, radical polymerizable compound (S) is 4.0%, photopolymerization initiator Irgacure 651 (manufactured by Ciba Specialty Chemicals) is from 0.4% A composition for a polymer dispersed liquid crystal display device was prepared, and a polymer dispersed liquid crystal display device was obtained by the above-described method. V90 of this element was 4.2V at 25 ° C, 4.4V at 0 ° C, 4.6V at -10 ° C, and 4.8V at -20 ° C.

Liquid crystal composition (A) is 78%, radical polymerizable compound (M) is 13.0%, radical polymerizable compound (S) is 8.6%, photopolymerization initiator Irgacure 651 (manufactured by Ciba Specialty Chemicals) is from 0.4% A composition for a polymer dispersed liquid crystal display device was prepared, and a polymer dispersed liquid crystal display device was obtained by the above-described method. V90 of this element was 4.2 V at 25 ° C., 4.3 V at 0 ° C., 4.4 V at −10 ° C., and 4.6 V at −20 ° C.
(Example 10)
Liquid crystal composition (A) is 78%, radical polymerizable compound (N) is 21.6%, radical polymerizable compound (S) is 4.0%, photopolymerization initiator Irgacure 651 (manufactured by Ciba Specialty Chemicals) is from 0.4% A composition for a polymer dispersed liquid crystal display device was prepared, and a polymer dispersed liquid crystal display device was obtained by the above-described method. V90 of this element was 4.2V at 25 ° C, 4.4V at 0 ° C, 4.6V at -10 ° C, and 4.8V at -20 ° C.

(Comparative Example 1)
The radically polymerizable compound (L) in Example 1 was changed to (P), and a polymer dispersion type liquid crystal display device was obtained by the same method. V90 of this element was 3.9 V at 25 ° C., 4.0 V at 0 ° C., 4.4 V at −10 ° C., and 6.8 V at −20 ° C.

(Comparative Example 2)
The radical polymerizable compound (L) in Example 1 was changed to (Q), and a polymer dispersion type liquid crystal display device was obtained by the same method. V90 of this element was 3.2 V at 25 ° C., 3.4 V at 0 ° C., 3.8 V at −10 ° C., and 8.3 V at −20 ° C.
(Comparative Example 3)
The radical polymerizable compound (L) in Example 5 was changed to (P), and a polymer dispersion type liquid crystal display device was obtained by the same method. V90 of this element was 3.5 V at 25 ° C., 3.8 V at 0 ° C., 4.8 V at −10 ° C., and 6.5 V at −20 ° C.
(Comparative Example 4)
The composition for a polymer-dispersed liquid crystal display element in which the radical polymerizable compound (L) in Example 1 was changed to (R), the radical polymerizable compound (L) was 13.0%, and the radical polymerizable compound (S) was 8.6%. The product was prepared and a polymer dispersed liquid crystal display device was obtained by the same method. V90 of this element was 7.8 V at 25 ° C., 8.4 V at 0 ° C., 9.9 V at −10 ° C., and 15.3 V at −20 ° C.

  Evaluation of liquid crystal compositions used in the above examples and comparative examples, their liquid crystal temperature ranges, used radical polymerizable compounds, photopolymerization initiators, and properties of polymer dispersed liquid crystal display devices obtained using these The results are summarized in Table 1.

From Table 1, in the comparative example not using the radical polymerization compound of the general formula (II-b), the driving voltage V90 at −20 ° C. is as high as 6V or more. On the other hand, in Examples using the radical polymerization compound of the general formula (II-b), it can be seen that the drive voltage V90 at −20 ° C. is as low as 5 V or less.

Claims (9)

General formula (I-a1), general formula (I-a2), and general formula (I-a3)

(Wherein R ⁴¹ , R ⁴² and R ⁴³ each independently represents an alkyl group having 1 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms, and is present in the alkyl group or alkenyl group. One or more CH ₂ groups may be substituted with oxygen atoms, assuming that the oxygen atoms are not directly bonded to each other,
A ¹¹ represents a 1,4-cyclohexylene group or a 1,3-dioxane-2,5-diyl group,
A ¹² and A ¹³ each independently represents a 1,4-phenylene group or a 1,4-cyclohexylene group, and the 1,4-phenylene group is unsubstituted or has one or two substituents It can have the above fluorine atom, chlorine atom, methyl group or trifluoromethyl group or trifluoromethoxy group,
X ^{1 to} X ¹⁰ each independently represent a hydrogen atom, a fluorine atom, a chlorine atom, a trifluoromethyl group or a trifluoromethoxy group,
Z ¹¹ to Z ¹⁴ each independently represent a single _{bond, -COO -, - CH 2 -CH} 2 - , or -CF ₂ O-,
n ¹¹ , n ¹² , n ¹³ and n ^{14 each} represents 0 or 1. )
Containing at least one kind from the compound group represented by the general formula (II-b)

(In the formula, B ⁵ , B ⁶ and B ⁷ each independently represent a single bond or an alkylene group having 1 to 19 carbon atoms, and the alkylene group is unsubstituted or has one or two substituents. It may have the above fluorine atom, methyl group, ethyl group, and one or two or more CH ₂ groups present in the alkylene group are oxygen atoms as those in which oxygen atoms are not directly bonded to each other, -CO-, -COO-, -OCO-, 1,4-phenylene group, pyridine-2,5-diyl group, pyrimidine-2,5-diyl group, 1,3-dioxane-2,5-diyl group, It may be substituted with a 1,4-cyclohexylene group, a bicyclo [2.2.2] octane-1,4-diyl group or 3,3′-spirobicyclobutylene, and the 1,4-phenylene group is unsubstituted. 1 or 2 or more fluorine atoms, chlorine atoms, methyl groups or trifluoromethyl groups or trifluoromethoxy as a substituent At least one CH ₂ group in the alkylene group may have the general formula (II-a)

(In the formula, each of B ¹ and B ² independently represents an alkyl group having 2 to 30 carbon atoms, and the alkyl group is unsubstituted or has one or more fluorine atoms as a substituent. 1 or 2 or more CH ₂ groups present in the alkyl group may be oxygen atoms, —CO—, —COO—, —OCO—, 1 on the assumption that oxygen atoms are not directly bonded to each other. , 4-phenylene group, pyridine-2,5-diyl group, pyrimidine-2,5-diyl group, 1,3-dioxane-2,5-diyl group, 1,4-cyclohexylene group, bicyclo [2.2.2 It may be substituted with an octane-1,4-diyl group or 3,3′-spirobicyclobutylene, provided that B ¹ and B ² are both non-polymerizable groups.
And the total number of carbon atoms of B ⁵ , B ⁶ and B ⁷ is 5 or more,
B ³ and B ⁴ each independently represent a hydrogen atom or a methyl group,
m and n each independently represent 1, 2 or 3. )
A composition for a polymer-dispersed liquid crystal element, comprising a polymerizable compound represented by the formula (1) and further containing a polymerization initiator. The compound represented by the general formula (II-b) is represented by the general formula (II-c)

(In the formula, each of B ⁸ , B ⁹ and B ¹⁰ independently represents a single bond or an alkylene group having 1 to 19 carbon atoms, and the alkylene group is unsubstituted or has one or two substituents. It may have one or more fluorine atoms, methyl groups, or ethyl groups, and one or two or more CH ₂ groups present in the alkylene group are oxygen atoms on the assumption that the oxygen atoms are not directly bonded to each other. , -CO-, -COO- or -OCO-, but the total number of carbon atoms of B ⁸ , B ⁹ and B ¹⁰ is 3 to 29,
B ¹¹ , B ¹² , B ¹³ and B ¹⁴ each independently represents an alkyl group having 2 to 25 carbon atoms, and one or two or more CH ₂ groups present in the alkyl group have an oxygen atom It may be substituted with an oxygen atom, —CO—, —COO— or —OCO— as those not directly bonded to each other. However, B ¹¹ , B ¹² , B ¹³ and B ¹⁴ are non-polymerizable groups. )
The composition for a polymer-dispersed liquid crystal element according to claim 1, represented by: General formula (III-a)

(Wherein R ³ and R ⁴ each independently represents an alkyl group having 1 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms, Two or more CH ₂ groups may be substituted with oxygen atoms, assuming that the oxygen atoms are not directly bonded to each other,
A ³ , A ⁴ and A ⁵ each independently represents a 1,4-phenylene group or a 1,4-cyclohexylene group, and the 1,4-phenylene group is unsubstituted or represents one or more substituents Can have two or more fluorine atoms, chlorine atoms, methyl groups or trifluoromethyl groups or trifluoromethoxy groups;
Z ⁵ and Z ⁶ each independently represents a single bond, —C≡C—, —COO— or —CH ₂ CH ₂ —,
n ³ represents 0, 1 or 2. However, when n ³ = 2, each A ³ and each Z ⁵ do not have to be the same. )
The composition for polymer-dispersed liquid crystal elements according to claim 1 or 2, comprising a compound represented by the formula:
Formula (IV-a)

Wherein R ⁵ represents an alkyl group having 1 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms, and one or more CH ₂ groups present in the alkyl group or alkenyl group are , As oxygen atoms are not directly bonded to each other, may be substituted with oxygen atoms,
A ⁶ represents a 1,4-phenylene group, a 1,4-cyclohexylene group or a 1,3-dioxane-2,5-diyl group, and the 1,4-phenylene group is unsubstituted or substituted. As one or more fluorine atoms, chlorine atoms, methyl groups or trifluoromethyl groups or trifluoromethoxy groups,
A ⁷ and A ⁸ are each independently 1,4-phenylene group, 1,4-cyclohexylene group, decahydronaphthalene-2,6-diyl group, 1,2,3,4-tetrahydronaphthalene-2,6 -Diyl group, 2,6-naphthylene group, or indan-2,5-diyl group, the 1,4-phenylene group, 1,2,3,4-tetrahydronaphthalene-2,6-diyl group, 2,6-naphthylene group and indan-2,5-diyl group are unsubstituted or have one or more fluorine, chlorine, methyl, trifluoromethyl or trifluoromethoxy groups as substituents Can have
Z ⁷ and Z ⁸ each independently represent a single bond, —C≡C—, —CH ₂ CH ₂ — or —CF ₂ O—, —COO—,
X ¹³ represents a fluorine atom, a chlorine atom, a trifluoromethyl group or a trifluoromethoxy group, a CF ₂ H group, an isocyanate group,
n ⁴ represents 0, 1 or 2. However, when n ⁴ = 2, each A ⁶ and each Z ⁷ do not have to be the same. )
A composition for a polymer-dispersed liquid crystal device according to claim 1, 2 or 3, comprising a compound represented by the formula: The composition for a polymer-dispersed liquid crystal element according to claim 4, comprising a compound represented by general formula (III-a) and general formula (IV-a). Compounds represented by general formula (I-a1), general formula (I-a2), group represented by general formula (I-a3), general formula (III-a), and general formula (IV-a) The total content of A is 59 to 89% by mass, the content of the compound represented by the general formula (II-b) is 10 to 40% by mass, and the content of the polymerization initiator is 0.1 to 2% by mass The composition for polymer dispersed liquid crystal elements according to claim 5. A reflective polymer dispersion type liquid crystal display element using the polymer dispersion type liquid crystal display element composition according to claim 1. 7. At least one having an electrode layer has two transparent substrates and a light control layer supported between the substrates, and the light control layer irradiates the composition according to claim 1 with ultraviolet rays. The obtained reflective polymer dispersed liquid crystal display element. 9. The polymer dispersed liquid crystal display element according to claim 8, wherein the light control layer is formed by forming a three-dimensional network structure of a transparent polymer substance in a continuous layer of liquid crystal.