JP3890841B2

JP3890841B2 - LCD light control window for vehicles

Info

Publication number: JP3890841B2
Application number: JP36633899A
Authority: JP
Inventors: 重明米森; 聡新山; 慎哉田原; 誠一宮坂
Original assignee: Asahi Glass Co Ltd
Current assignee: AGC Inc
Priority date: 1999-12-24
Filing date: 1999-12-24
Publication date: 2007-03-07
Anticipated expiration: 2019-12-24
Also published as: JP2001180264A

Description

【０００１】
【発明の属する技術分野】
本発明は車両の前方・後方または側方からの明光による車内の者の眩惑を防ぐとともに、不通電時の視界の妨害をなくすことができる車両用液晶調光窓に関する。
【０００２】
【従来の技術】
太陽光など車外からの明光を防ぎ、曇天や夜などには光の透過率を変化させて車両室内の光量を調節するために、液晶調光窓が考案されている。従来の液晶調光窓の場合、電界印加時に透明となり、非印加時に不透明となるように動作する。
【０００３】
【発明が解決しようとする課題】
しかし、上記従来の液晶調光窓を車両用に使用した場合には、停電等で通電が止まった際に液晶が視界を遮り、安全性が確保されないという問題があった。
【０００４】
本発明は、上記従来の課題に鑑みなされたものであり、その目的は、不通電時の視界妨害をなくすことができる車両用液晶調光窓を提供することにある。
【０００５】
【課題を解決するための手段】
上記目的を達成するために、本発明は電圧の印加により不透明になる液晶調光材料が２枚の透明電極付透明材間に封入された調光素子を備えたことを特徴とする車両用液晶調光窓を提供する。本発明の液晶調光材料としては、ダイナミックスキャタリングモ−ドの液晶素子、配向型液晶／高分子複合体素子などが使用できるが、大面積時の信頼性や消費電力の点より電界効果型の液晶素子を使用することが好ましい。
【０００６】
特に、上記車両用液晶調光窓において、液晶調光材料は、液晶と以下の式で示された化合物を含有する未硬化の硬化性化合物との混合物を調製し、硬化性化合物を硬化させることにより形成されることが好ましい。
【０００７】
【化２】

また、上記車両用液晶調光窓において、透明電極付透明材は樹脂からなり、かつ調光素子は硝子板に貼り付けられていることが好ましい。
【０００８】
【発明の実施の形態】
以下、本発明の実施の形態（以下実施形態という）について説明する。
【０００９】
図１には、本発明にかかる車両用液晶調光窓に使用される車両用液晶調光硝子の一実施形態の構成の断面図が示される。図１において、２枚の硝子基板１０には、それぞれ透明電極１２が形成されており、この透明電極１２には、さらに配向膜１３が形成されていて、本発明にかかる透明電極付透明材を構成している。また、上記透明電極１２側を対向させて硝子基板１０の間に液晶調光材料１４を挟持させ、本発明にかかる調光素子が形成される。この液晶調光材料１４は、電圧の印加時に不透明になり、非印加時に透明になるリバースモード型である。ここで、配向膜１３はポリイミド等の高分子薄膜を用いることができる。またシランカップリング材等によって透明電極の表面を処理した面を代用することができる。さらに、配向膜１３を使用せず透明電極間に直接液晶調光材料１４を挟持させることもできる。
【００１０】
なお、本発明にかかる車両用液晶調光窓は、図１に示された例に限られるものではなく、硝子基板１０の代わりに、例えばポリカーボネート、アクリル、ウレタンなどのフィルム状の基板を使用することも可能である。また、片面が硝子、逆面がポリマーフィルムになっている基板も使用できる。特に樹脂フィルム基板を使用した調光窓については、剛性を付与するために硝子板に貼り付けることができる。例えば、フィルム基板を接着層を介して一枚の硝子板に貼り付けたり、または、接着層を介して２枚の硝子板に挟持することができる。さらに、透明電極付き硝子板と透明電極付き樹脂フィルムの間に液晶調光材料を挟持することもできる。
【００１１】
この液晶調光材料１４は、液晶と未硬化の硬化性化合物との混合物を調製し、硬化性化合物を硬化させることにより形成する。液晶としては、例えばシアノ系ネマティック液晶、誘電異方性が負であるネマティック液晶等があげられる。また、硬化性化合物としては、以下に示される化合物を含有するものがあげられる。
【００１２】
【化３】

上記式（１）の硬化性化合物中のメソゲン構造部と硬化部位との間に分子運動性の高いオキシアルキレン構造を導入することで、硬化過程における硬化部位の分子運動性を向上させ、短時間の硬化反応においても、電圧印加／非印加時の状態が安定で信頼性が高く、かつコントラストも高い液晶光学素子が得られる。
【００１３】
式（１）の硬化部位（Ａ _１、Ａ _２）としては、一般に硬化触媒とともに光硬化、熱硬化可能な上記の官能基であればいずれでもよいが、なかでも、硬化時の温度を制御できることから光硬化に適するアクリロイル基、メタクリロイル基が好ましい。
【００１４】
式（１）のオキシアルキレン部のＲ _１およびＲ _２の炭素数については、その運動性から２〜６が好ましく、さらに炭素数２のエチレン基の連鎖および炭素数３のプロピレン基が好ましい。
【００１５】
式（１）のメソゲン構造部（Ｚ）としては、１，４−フェニレン基が２個以上連結した２価のポリフェニレンが好ましい。また、このポリフェニレン基中の一部の１，４−フェニレン基が１，４−シクロヘキシレン基で置換された２価の有機基であってもよい。
【００１６】
これらポリフェニレン基や２価の有機基の水素原子の一部または全部は炭素数１〜２のアルキル基、ハロゲン原子、カルボキシル基、アルコキシカルボニル基などの置換基に置換されていてもよい。好ましいＺは、１，４−フェニレン基が２個連結したビフェニレン基（以下、４，４’−ビフェニレン基という。）、３個連結したターフェニレン基、およびこれらの水素原子の１〜４個が炭素数１〜２のアルキル基、フッ素原子、塩素原子もしくはカルボキシル基に置換された２価の有機基である。最も、好ましいＺは置換基を有しない４，４’−ビフェニレン基である。
【００１７】
式（１）のｎ、ｍはあまり大きいと液晶との相溶性が低下するため、それぞれ独立に１〜１０であり、硬化後の素子特性を考慮すると１〜４がさらに好ましい。
【００１８】
液晶と未硬化の硬化性化合物の混合物が硬化触媒を含有していてもよく、光硬化の場合、ベンゾインエーテル系、アセトフェノン系、フォスフィンオキサイド系などの一般に光硬化樹脂に用いられる光重合開始剤を使用できる。
【００１９】
熱硬化の場合は、硬化部位の種類に応じて、パーオキサイド系、チオール系、アミン系、酸無水物系などの硬化触媒を使用でき、また、必要に応じてアミン類などの硬化助剤も使用できる。
【００２０】
硬化触媒の含有量は、含有する未硬化の硬化性化合物の２０ｗｔ％以下が好ましく、硬化後の硬化物の高い分子量や高い比抵抗が要求される場合、１〜１０ｗｔ％とすることがさらに好ましい。
【００２１】
また、電界印加／非印加時の素子のコントラストを向上させるために、液晶と未硬化の硬化性化合物の混合物にカイラル剤を添加することもできる。
【００２２】
液晶と未硬化の硬化性化合物の混合物中の未硬化の硬化性化合物は、液晶との相溶性を向上させるために、式（１）でｎ、ｍの異なる複数の未硬化の硬化性化合物を含んでいてもよく、それによりさらにコントラストを改善することができる。
【００２３】
一方、液晶と未硬化の硬化性化合物の混合物は、混合後均質な溶液であることが好ましい。また、液晶と未硬化の硬化性化合物の混合物は、電極付き基板に挟持されるとき、液晶相を示していてもよい。
【００２４】
液晶と未硬化の硬化性化合物の混合物は、硬化されるとき、液晶相を示していてもよい。液晶と未硬化の硬化性化合物の混合物を挟持する電極付き基板の電極表面を直接研磨したり、樹脂の薄膜を設けそれをラビングするなどして、電極表面に液晶を配向させる機能を付与することもでき、それにより、液晶と未硬化の硬化性化合物の混合物を挟持する際のむらを低減させることもできる。
【００２５】
また、一対の配向処理済み基板の配向方向の組み合わせとしては、平行、直交、いずれでもよく、混合物挟持時のむらが最小となるよう角度を設定すればよい。
【００２６】
以上に述べた液晶と未硬化の硬化性化合物との混合物は、透明電極１２付きの硝子基板１０あるいは透明電極付きフィルム等に挟持され、上記方法で硬化性化合物が硬化されることにより液晶調光材料１４となる。これにより、図１に示された車両用液晶調光硝子が完成する。この場合、上記透明電極１２付きの硝子基板１０を車両用の窓硝子としあるいは電極付きフィルムを車両用の窓硝子に接着等すれば本発明にかかる車両用液晶調光窓となる。この液晶調光材料１４は、上述の通りリバースモード型であるので、車両の停電時もしくは不通電時でも視界を妨げることがない。
【００２７】
【実施例】
以下に、本発明にかかる車両用液晶調光窓の実施例および比較例を説明する。
【００２８】
［実施例１］
カイラル剤（メルク社製Ｓ−８１１とメルク社製Ｃ１５の重量比１：１の混合物）を２．５ｗｔ％溶解したシアノ系ネマティック液晶（メルク社製ＢＬ−００９）９５部、上記式（１）の未硬化の硬化性化合物の具体例として以下の式（２）に示される化合物５部、２、２−ジメトキシ−２−フェニルアセトフェノン０．１５部の混合物（混合物Ａ）を調製した。
【００２９】
【化４】

この式（２）の化合物は、式（１）でＡ _１、Ａ _２がアクリロイル基で、Ｒ _１、Ｒ _２がエチレン基で、Ｚのメソゲン構造部が４，４’−ビフェニレン基で、ｎ、ｍがともに１である場合に相当する。
【００３０】
次に、硝子上に透明電極を形成し、更にその上に水平配向用ポリイミド薄膜を形成してそれを一方向にラビングした一対の車両用硝子板を、ラビング方向が直交するようポリイミド薄膜側を対向させ、微量の直径１３μｍの樹脂ビーズを介して、一部に切り欠けを設けて四辺に幅約３ｍｍで印刷したエポキシ樹脂により張り合わせて、硝子容器（セル）を作製した。このセルに混合物Ａを真空注入法にて注入し、切り欠き部をエポキシ樹脂で封止した。このセルを、１２０℃に温度設定した恒温槽中に２０分間保持した後２５℃まで冷却した。その後、このセルを２５℃に保持した状態で、主波長が約３６５ｎｍのＨｇＸｅランプを用いて硝子面の両側からそれぞれ約３ｍＷ／ｃｍ ^２の強度の紫外線を１０分間照射して、液晶調光材料が２枚の硝子に挟まれた形態の車両用液晶調光硝子を作製した。得られた液晶調光硝子は高い透明性を示した。
【００３１】
この液晶調光硝子の対向する透明電極間に、５０Ｈｚの矩形波５０Ｖｒｍｓを印加したところ不透明な散乱状態となり、電圧印加をやめると元の透明状態に戻った。
【００３２】
この液晶調光硝子を車両に搭載し、本発明にかかる車両用液晶調光窓とした。
【００３３】
［実施例２］
誘電異方性が負であるネマティック液晶（Ｔc ＝９８℃、Δε= −５．６、Δｎ＝０．２２０）８０部、上記式（１）の未硬化の硬化性化合物の具体例として以下の式（３）で示される化合物２０部、ベンゾインイソプロピルエーテル０．２部の混合物（混合物Ｂ）を調製した。
【００３４】
【化５】

この式（３）の化合物は、式（１）でＡ _１、Ａ _２がアクリロイル基で、Ｒ _１、Ｒ _２がプロピレン基で、Ｚのメソゲン構造部が４，４’−ビフェニレン基で、ｎ、ｍがともに１である場合に相当する。
【００３５】
次に、硝子上に透明電極を形成し、更にその上に垂直配向用ポリイミド薄膜を形成した一対の車両用硝子板をポリイミド薄膜側を対向させ、微量の直径６μｍの樹脂ビーズを介して、一部に切り欠けを設けて四辺に幅約３ｍｍで印刷したエポキシ樹脂により張り合わせて、硝子容器（セル）を作製した。このセルに混合物Ｂを真空注入法にて注入し、切り欠き部をエポキシ樹脂で封止した。このセルを２５℃に保持した状態で、主波長が約３６５ｎｍのＨｇＸｅランプを用いて硝子面の両側からそれぞれ約１ｍＷ／ｃｍ ^２の紫外線を１０分間照射して、液晶調光材料が２枚の硝子に挟まれた形態の車両用液晶調光硝子を作製した。得られた液晶調光硝子は高い透明性を示した。
【００３６】
この液晶調光硝子の対向する透明電極間に、１ｋＨｚの矩形波５０Ｖｒｍｓを印加したところ不透明な散乱状態となり、電圧印加をやめると元の透明状態に戻った。
【００３７】
この液晶調光硝子を車両に搭載することにより、本発明にかかる車両用液晶調光窓とできる。
【００３８】
［実施例３］
垂直配向用ポリイミドの希薄溶液を透明電極付き透明フィルムの透明電極上にグラビアコーターで塗布し、溶媒を乾燥除去してポリイミド薄膜を形成した。ポリイミド薄膜面に６μｍの微量スペーサーを散布後、ポリイミド面を対向させた１対のフィルムの間に実施例２の混合物Ｂをゴムロ−ルを用いて挟持した。この混合物Ｂを挟持したフィルムを２５℃に保持した状態で、主波長が約３６５ｎｍのＨｇＸｅランプを用いてフィルム面の両側からそれぞれ約１ｍＷ／ｃｍ ^２の紫外線を１０分間照射して、液晶調光材料が２枚の透明電極付きフィルムに挟まれた形態の調光フィルムを作製した。調光フィルムは透明であった。この調光フィルムの透明電極部端に電極端子加工を施し、合わせ硝子用中間膜を介して２枚の車両用硝子間に挟持して車両用合わせ硝子を作製した。
【００３９】
得られた車両用合わせ硝子は透明であり、調光フィルムの端子間に１ｋＨｚの矩形波５０Ｖｒｍｓを印加したところ不透明な散乱状態となり、電圧印加をやめると元の透明状態に戻った。
【００４０】
この車両用合わせ硝子を車両に搭載することにより、本発明にかかる車両用液晶調光窓とできる。
【００４１】
【発明の効果】
以上説明したように、本発明によれば、車両用液晶調光窓を、電界印加時に不透明になり、電界非印加時に透明になるリバースモード型とできるので、停電時の視界を確保できるとともに、必要な時に、車両に入射する光を制御して、防眩、遮熱、遮光のような優れた効果を有することができる。
【図面の簡単な説明】
【図１】本発明にかかる車両用液晶調光窓に使用される車両用液晶調光硝子の一実施形態の構成の断面図である。
【符号の説明】
１０硝子基板、１２透明電極、１３配向膜、１４液晶調光材料。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a liquid crystal light control window for a vehicle that can prevent a person in the vehicle from being dazzled by bright light from the front, rear, or side of the vehicle, and that can prevent the visual field from being obstructed when the power is not supplied.
[0002]
[Prior art]
A liquid crystal dimming window has been devised to prevent bright light from outside the vehicle such as sunlight and to adjust the amount of light in the vehicle interior by changing the light transmittance in cloudy weather or at night. In the case of a conventional liquid crystal dimming window, it operates so as to be transparent when an electric field is applied and opaque when no electric field is applied.
[0003]
[Problems to be solved by the invention]
However, when the above conventional liquid crystal light control window is used for a vehicle, there is a problem that when the power supply is stopped due to a power failure or the like, the liquid crystal blocks the field of view and safety is not ensured.
[0004]
The present invention has been made in view of the above-described conventional problems, and an object of the present invention is to provide a liquid crystal light control window for a vehicle that can eliminate a visual field disturbance at the time of de-energization.
[0005]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides a liquid crystal for vehicles, comprising a light control element in which a liquid crystal light control material that becomes opaque when a voltage is applied is enclosed between two transparent materials with a transparent electrode. Provide a dimming window. As the liquid crystal light control material of the present invention, a liquid crystal element of a dynamic scattering mode, an alignment type liquid crystal / polymer composite element, etc. can be used. However, the field effect type is preferable in terms of reliability and power consumption in a large area. It is preferable to use the liquid crystal element.
[0006]
In particular, in the vehicle liquid crystal light control window, the liquid crystal light control material is prepared by preparing a mixture of liquid crystal and an uncured curable compound containing a compound represented by the following formula, and curing the curable compound. It is preferably formed by.
[0007]
[Chemical 2]

In the vehicle liquid crystal light control window, the transparent material with a transparent electrode is preferably made of a resin, and the light control element is preferably attached to a glass plate.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention (hereinafter referred to as embodiments) will be described.
[0009]
FIG. 1 is a sectional view showing a configuration of an embodiment of a liquid crystal light control glass for vehicles used in a liquid crystal light control window for vehicles according to the present invention. In FIG. 1, a transparent electrode 12 is formed on each of two glass substrates 10, and an alignment film 13 is further formed on the transparent electrode 12, and the transparent material with a transparent electrode according to the present invention is used. It is composed. Further, the liquid crystal light control material 14 is sandwiched between the glass substrates 10 with the transparent electrode 12 side facing each other, whereby the light control element according to the present invention is formed. This liquid crystal light control material 14 is a reverse mode type which becomes opaque when a voltage is applied and becomes transparent when a voltage is not applied. Here, the alignment film 13 can be a polymer thin film such as polyimide. Moreover, the surface which processed the surface of the transparent electrode with the silane coupling material etc. can be substituted. Further, the liquid crystal light control material 14 can be sandwiched directly between the transparent electrodes without using the alignment film 13.
[0010]
The vehicle liquid crystal light control window according to the present invention is not limited to the example shown in FIG. 1, and a film-like substrate such as polycarbonate, acrylic, or urethane is used instead of the glass substrate 10. It is also possible. A substrate having a glass on one side and a polymer film on the other side can also be used. In particular, a light control window using a resin film substrate can be attached to a glass plate in order to impart rigidity. For example, the film substrate can be attached to one glass plate via an adhesive layer, or can be sandwiched between two glass plates via an adhesive layer. Further, a liquid crystal light control material can be sandwiched between a glass plate with a transparent electrode and a resin film with a transparent electrode.
[0011]
The liquid crystal light adjusting material 14 is formed by preparing a mixture of liquid crystal and an uncured curable compound and curing the curable compound. Examples of the liquid crystal include a cyano nematic liquid crystal and a nematic liquid crystal having negative dielectric anisotropy. Moreover, as a sclerosing | hardenable compound, what contains the compound shown below is mention | raise | lifted.
[0012]
[Chemical 3]

By introducing an oxyalkylene structure having high molecular mobility between the mesogenic structure portion and the cured site in the curable compound of the above formula (1), the molecular mobility of the cured site in the curing process is improved, and the time is shortened. Also in the curing reaction, a liquid crystal optical element can be obtained in which the state during voltage application / non-application is stable and reliable, and the contrast is high.
[0013]
The curing site (A ₁ , A ₂ ) of the formula (1) may be any of the above functional groups that can be photocured and thermally cured together with a curing catalyst. In particular, the temperature during curing can be controlled. To acryloyl group and methacryloyl group suitable for photocuring.
[0014]
The number of carbon atoms of R ₁ and R _{2 in} the oxyalkylene moiety of formula (1) is preferably 2 to 6 because of its mobility, and more preferably a chain of ethylene groups having 2 carbon atoms and a propylene group having 3 carbon atoms.
[0015]
As the mesogen structure part (Z) of the formula (1), divalent polyphenylene in which two or more 1,4-phenylene groups are linked is preferable. Further, a divalent organic group in which a part of the 1,4-phenylene group in the polyphenylene group is substituted with a 1,4-cyclohexylene group may be used.
[0016]
Some or all of the hydrogen atoms of these polyphenylene groups and divalent organic groups may be substituted with substituents such as alkyl groups having 1 to 2 carbon atoms, halogen atoms, carboxyl groups, and alkoxycarbonyl groups. Preferred Z is a biphenylene group in which two 1,4-phenylene groups are linked (hereinafter referred to as 4,4′-biphenylene group), a terphenylene group in which three 1,4-phenylene groups are linked, and 1 to 4 of these hydrogen atoms. It is a divalent organic group substituted by an alkyl group having 1 to 2 carbon atoms, a fluorine atom, a chlorine atom or a carboxyl group. Most preferred Z is a 4,4′-biphenylene group having no substituent.
[0017]
If n and m in the formula (1) are too large, the compatibility with the liquid crystal is lowered. Therefore, each is independently 1 to 10, and 1 to 4 is more preferable in consideration of element characteristics after curing.
[0018]
A mixture of liquid crystal and an uncured curable compound may contain a curing catalyst. In the case of photocuring, a photopolymerization initiator generally used for photocuring resins such as benzoin ether, acetophenone, and phosphine oxide. Can be used.
[0019]
In the case of thermosetting, a curing catalyst such as peroxide, thiol, amine, or acid anhydride can be used depending on the type of curing site, and if necessary, curing aids such as amines can also be used. Can be used.
[0020]
The content of the curing catalyst is preferably 20 wt% or less of the uncured curable compound to be contained, and more preferably 1 to 10 wt% when a high molecular weight or high specific resistance of the cured product after curing is required. .
[0021]
Further, a chiral agent can be added to a mixture of liquid crystal and an uncured curable compound in order to improve the contrast of the device when an electric field is applied / not applied.
[0022]
In order to improve the compatibility with the liquid crystal, the uncured curable compound in the mixture of the liquid crystal and the uncured curable compound includes a plurality of uncured curable compounds having different n and m in the formula (1). May be included, thereby further improving the contrast.
[0023]
On the other hand, the mixture of the liquid crystal and the uncured curable compound is preferably a homogeneous solution after mixing. Further, the mixture of the liquid crystal and the uncured curable compound may exhibit a liquid crystal phase when sandwiched between the substrates with electrodes.
[0024]
The mixture of liquid crystal and uncured curable compound may exhibit a liquid crystal phase when cured. Giving a function to orient the liquid crystal on the electrode surface by directly polishing the electrode surface of the substrate with the electrode that sandwiches the mixture of liquid crystal and uncured curable compound, or by rubbing it with a resin thin film. It is also possible to reduce unevenness when sandwiching the mixture of the liquid crystal and the uncured curable compound.
[0025]
Further, the combination of the alignment directions of the pair of alignment-treated substrates may be either parallel or orthogonal, and the angle may be set so as to minimize the unevenness when the mixture is sandwiched.
[0026]
The mixture of the liquid crystal and the uncured curable compound described above is sandwiched between the glass substrate 10 with the transparent electrode 12 or the film with the transparent electrode, and the liquid crystal dimming is performed by curing the curable compound by the above method. It becomes the material 14. Thereby, the liquid crystal light control glass for vehicles shown in FIG. 1 is completed. In this case, if the glass substrate 10 with the transparent electrode 12 is used as a window glass for a vehicle or a film with an electrode is bonded to a window glass for a vehicle, the liquid crystal light control window for a vehicle according to the present invention is obtained. Since the liquid crystal light-modulating material 14 is a reverse mode type as described above, the visual field is not hindered even when the vehicle is blacked out or not energized.
[0027]
【Example】
Below, the Example and comparative example of the liquid crystal light control window for vehicles concerning this invention are demonstrated.
[0028]
[Example 1]
95 parts of a cyano nematic liquid crystal (BL-009 made by Merck) in which 2.5% by weight of a chiral agent (a mixture of S-811 made by Merck and C15 made by Merck in a weight ratio of 1: 1) was dissolved, and the above formula (1) As a specific example of the uncured curable compound, a mixture (mixture A) of 5 parts of a compound represented by the following formula (2) and 0.15 part of 2,2-dimethoxy-2-phenylacetophenone was prepared.
[0029]
[Formula 4]

The compound of the formula (2) is represented by the formula (1), wherein A ₁ and A ₂ are acryloyl groups, R ₁ and R ₂ are ethylene groups, the mesogenic structure of Z is 4,4′-biphenylene group, n , M are both 1.
[0030]
Next, a transparent electrode is formed on the glass, a polyimide thin film for horizontal orientation is further formed thereon, and a pair of vehicle glass plates are rubbed in one direction, and the polyimide thin film side is placed so that the rubbing directions are orthogonal to each other. The glass containers (cells) were manufactured by facing each other through a small amount of resin beads having a diameter of 13 μm and pasting them with an epoxy resin having a cutout in a part and printing with a width of about 3 mm on four sides. The mixture A was injected into this cell by a vacuum injection method, and the notch was sealed with an epoxy resin. The cell was kept in a thermostat set at 120 ° C. for 20 minutes and then cooled to 25 ° C. Thereafter, with this cell held at 25 ° C., UV light having an intensity of about 3 mW / cm ² was irradiated from both sides of the glass surface for 10 minutes using an HgXe lamp having a dominant wavelength of about 365 nm, and a liquid crystal light control material A liquid crystal light control glass for vehicles having a shape sandwiched between two glasses was produced. The obtained liquid crystal light control glass showed high transparency.
[0031]
When a 50 Hz rectangular wave of 50 Vrms was applied between the opposing transparent electrodes of the liquid crystal light control glass, an opaque scattering state was obtained, and when the voltage application was stopped, the original transparent state was restored.
[0032]
This liquid crystal light control glass was mounted on a vehicle to provide a vehicle liquid crystal light control window according to the present invention.
[0033]
[Example 2]
80 parts of nematic liquid crystal having negative dielectric anisotropy (Tc = 98 ° C., Δε = −5.6, Δn = 0.220), specific examples of the uncured curable compound of the above formula (1) are as follows: A mixture (mixture B) of 20 parts of the compound represented by the formula (3) and 0.2 part of benzoin isopropyl ether was prepared.
[0034]
[Chemical formula 5]

The compound of the formula (3) is represented by the formula (1), wherein A ₁ and A ₂ are acryloyl groups, R ₁ and R ₂ are propylene groups, the mesogenic structure of Z is 4,4′-biphenylene group, n , M are both 1.
[0035]
Next, a transparent electrode is formed on the glass, and a pair of vehicle glass plates on which a polyimide thin film for vertical alignment is further formed are opposed to the polyimide thin film side, and a small amount of resin beads having a diameter of 6 μm are interposed therebetween. A glass container (cell) was manufactured by providing notches in the parts and pasting them together with an epoxy resin printed with a width of about 3 mm on four sides. The mixture B was injected into this cell by a vacuum injection method, and the notch was sealed with an epoxy resin. With this cell held at 25 ° C., UV light of about 1 mW / cm ² was irradiated from both sides of the glass surface for 10 minutes using a HgXe lamp having a dominant wavelength of about 365 nm, and ^two liquid crystal light control materials were used. A liquid crystal light control glass for a vehicle sandwiched between glasses was produced. The obtained liquid crystal light control glass showed high transparency.
[0036]
When a 1 kHz rectangular wave of 50 Vrms was applied between the opposing transparent electrodes of the liquid crystal light control glass, it became an opaque scattering state, and when the voltage application was stopped, the original transparent state was restored.
[0037]
By mounting this liquid crystal light control glass on a vehicle, the vehicle liquid crystal light control window according to the present invention can be obtained.
[0038]
[Example 3]
A dilute solution of polyimide for vertical alignment was applied onto a transparent electrode of a transparent film with a transparent electrode by a gravure coater, and the solvent was removed by drying to form a polyimide thin film. After spraying a 6 μm trace amount spacer on the polyimide thin film surface, the mixture B of Example 2 was sandwiched between a pair of films facing the polyimide surface using a rubber roll. Liquid crystal dimming was performed by irradiating UV light of about 1 mW / cm ² from both sides of the film surface for 10 minutes using a HgXe lamp having a dominant wavelength of about 365 nm with the film holding the mixture B held at 25 ° C. The light control film of the form from which the material was pinched | interposed into the film with two transparent electrodes was produced. The light control film was transparent. The terminal of the transparent electrode portion of the light control film was subjected to electrode terminal processing, and sandwiched between two vehicle glasses via a laminated glass interlayer film to produce a laminated glass for vehicles.
[0039]
The obtained laminated glass for vehicles was transparent. When a 1 kHz rectangular wave of 50 Vrms was applied between the terminals of the light control film, it became an opaque scattering state, and when the voltage application was stopped, it returned to the original transparent state.
[0040]
By mounting this laminated glass for vehicles on a vehicle, the liquid crystal light control window for vehicles according to the present invention can be obtained.
[0041]
【The invention's effect】
As described above, according to the present invention, the liquid crystal light control window for a vehicle can be a reverse mode type that becomes opaque when an electric field is applied and becomes transparent when an electric field is not applied. When necessary, the light incident on the vehicle can be controlled to have excellent effects such as anti-glare, heat shielding and light shielding.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a configuration of an embodiment of a vehicle liquid crystal light control glass used in a vehicle liquid crystal light control window according to the present invention.
[Explanation of symbols]
10 Glass substrate, 12 Transparent electrode, 13 Alignment film, 14 Liquid crystal light control material.

Claims

A liquid crystal light-modulating material formed of a reverse mode liquid crystal and a cured product that becomes opaque when a voltage is applied and becomes transparent when a voltage is not applied is sealed between two transparent materials with a transparent electrode , and voltage is applied or not applied A liquid crystal dimming window for vehicles, comprising a dimming element that operates in a field effect manner .

The liquid crystal light-modulating material is formed by preparing a mixture of a liquid crystal and an uncured curable compound containing a compound represented by the following formula, and curing the curable compound to obtain the cured product. The liquid crystal light control window for a vehicle according to claim 1.

The liquid crystal light control window for a vehicle according to claim 2, wherein in the compound represented by the formula, R ₁ and R ₂ of the oxyalkylene moiety have 3 carbon atoms .

The vehicle liquid crystal dimming window according to any one of claims 1 to 3, wherein a function of aligning liquid crystal is provided on a surface of the transparent electrode .

The vehicle liquid crystal light control window according to any one of claims 1 to 4, wherein the transparent material with a transparent electrode is made of a resin, and the light control element is attached to a glass plate. .