201224594 六、發明說明： 【發明所屬之技術領域】 本發明係有關液晶元件的電光學特性的改良技術。 【先前技術】 在=本專利第251G15G號公報（專利文獻υ公開的液晶顯 置中，係使液晶分子在下述旋轉方向來扭轉配向以提高電光學特性裝 該旋轉方向即：組合分別實施於對向配置的一對基板的各個基 向(之先戶^制Γ轉方向（第1旋轉方向）的相反旋轉方向（第 -旋轉方向）（先剛例1)。這種液晶顯示裝置（液晶元件）的動 式被稱作逆 TN (Reverse τ\νί_ Neumtie，逆㈣㈣ μ。 另外，日本特開2007·293278號公報（專利文獻2)公開一種液曰 元件，其添加有旋紐㈣，職練材料係使液晶分子朝向：組: 分別實施於對向配置的-對基板的配向處理的方向之 向（第m轉方向）的相反旋轉方向（第2旋轉方向）來二== 晶分子朝上述幻旋轉方向扭轉配向以增加液晶層内的變形， 閾值電壓以達低電壓驅動（先前例2)。 降低 另外’在日本特開細·1嶋5號公報（專利文獻3)公開有如下 技術，其錢在初始狀態下處於錄扭轉（splaytwlst)配向，而當施 加1次縱向電場時為反扭轉配向之敎的逆TN型液晶元件（先前例3)。 兹』：曰^2例1的液晶顯示裝置的反扭轉配向狀態不穩定’ 藉由對液阳層施加較高的電麼雖可獲得反扭轉配向狀態，但會有隨著 時間經過而轉移為順扭轉配向狀態之不良情況。另外，先前例2的液 晶疋件絲具有如上所述降低閾值電壓的優點，然而域電壓後會立 右）轉移為順向配向狀態’存在反而提高閾值電壓的 牛先前例3中的逆™型液晶元件基於電光學特性的 的餘地。例如先前例3中的銳利度(8_顧） 最佳為1.7左右，尚待進一步的改良。 【專利文獻1】日本專利第2510150號公報 201224594 【專利文獻·2】日本特開2007-293278號公報 【專利文獻3】日本特開2010-186045號公報 【發明内容】 本發明涉及的具體方式的目的之一在於’提供一種可提高反杻轉 配向狀態的穩定性，還能達成電光學特性的提升的逆ΤΝ型液晶元件。 本發明涉及的一個方式的液晶元件的特徵在於，具有：（a)第i 基板和第2基板’其等各有一個面實施配向處理，而且彼此對向配置； (b)液晶層，其設置於上述第】基板的—個面與上述第2基板的一個 面之間；（〇#«合物牆’料沿著層厚方向設置於上晶層内， ⑷上述第i基板和上述第2基板的上述配向處理的方向被相對設定 成易於使上述液晶層的液晶分子產生朝第】旋轉方向扭轉的第i配向 狀態，U)上述液晶層含有旋光性材料並且具有朝上述第1旋轉 扭轉的配向狀態’其中職紐㈣具備使上述液晶分子朝與上 1旋轉方向相反的第2旋轉方向扭轉的性質。 ，據上述構造’藉由對液晶層導人聚合物牆，能穩定維持朝向第 方向扭轉的配向狀態（反扭轉狀態）。例如對形成液晶層時的液 添加光硬化型樹脂，將液晶材料注入第i基板與第2基板 加電壓等，層從作為初始狀態的擴散扭轉狀態轉移到 具有進仃光照射’從而能夠簡單地形成聚合物牆。 優良。因此根據上述構造能提供一種可接古 性’還能達成電光學特性的提升的逆種配向《的穩定 具有件中’較佳為多個聚合物牆彼此結合’在俯視觀察時 由此能進-步提高反扭轉狀態的穩 型樹脂照射光時使用具有網格狀的遮光部分4二在= 形成這麵格狀的聚合物牆。 ）^了簡單 述液二為旋光性材料添加有使其旋光性間距與上 ι仪Ba層的層厚之比達0.04以上〇 4以下的量。 201224594 性單==元件中’較佳為多個聚合物牆係使光硬化型液晶 另外’上述液晶元件中，液晶層的上述液晶分子的㈣例如設為 實質上90度。而且扭轉角可以為9〇度左右，例如8〇度〜ιι〇度左右。 【實施方式】 下面參照圖式說明本發明實施方式。 第1圖是示意性表示逆TN型液晶元件的動作的示意圖。逆丁时 液晶元件的基本構造為具有對向配置的上側基板丨和下側基板2、設 置於其等之_液晶層3。對上娜板i和下側基板2各自的表面實 施摩擦配向處理等配向處理（圖中箭頭所示）。這些配向處理的方向以 90度左右的角度彼此交又’將上側基板丨與下側基板2相對配置。液 晶層3係透過將向列魏晶材料注人到上側基板丨與下側基板2之間 而形成。液晶層3使用驗晶材料巾添加有旋級材料，該旋光性材 料產生使液晶分子在其方位角方向朝特定方向（第丨圖的例子中為右 旋轉方向）扭轉的作用。若設上側基板i與下側基板2的相互間隔（液 晶胞厚度）為d、旋光性材料的旋光性間距為p，則其等的比d/p的值 例如設定為0.4左右。這種逆TN型液晶元件在初始狀態下係處於液晶 層3擴散配向同時扭轉的擴散扭轉狀態。若對該處於擴散扭轉狀態的 液晶層3施加超過飽和電壓的電壓，則轉移為液晶分子朝左旋轉方向 扭轉的反扭轉狀態（均勻扭轉狀態）。在這種反扭轉狀態的液晶層3 中，基體（bulk)中的液晶分子傾斜，因此能顯現出降低液晶元件的 驅動電壓的效果。然而，通常這種反扭轉狀態大多不穩定，隨著時間 經過會自然轉移到作為初始狀態的擴散扭轉狀態。於是，本案發明人 便構思將聚合物網路導入至液晶層3内，以求穩定液晶層3的配向狀 態。 第2圖是示意性說明在液晶層内形成聚合物網路的方法（高分子 穩定法）的圖。如第2圖（A)所示，當在上側基板1與下側基板2 之間形成液的層3時，使用包含液晶分子如和光硬化型（例如紫外線 硬化型）的液晶性單體3b的液晶材料。接著如第2圖（B)所示，使 201224594 用分別設置於上側基板1與下側基板2上的上側電極4、下側電極5 向液晶層3施加電壓，從而使液晶層3的配向狀態轉移為反扭轉狀鲅。 ，後如第2圖（c)所示，在液晶層3維持反扭轉狀態的期間内對該^ 晶層3.進行光照射（例如紫外線照射）。由此使得液晶性單體3b ^分 子化，而在液晶層3内形成聚合物網路。藉由形成這種聚合物網:: 使得反扭轉狀態的穩定性提高，而不易轉移為初始狀態的擴散扭轉狀 態0 第3圖是示意性說明在液晶層形成聚合物牆的方法的圖。並且對 與上述第2圖共同的構造使用相同符號，對這些内容省略說明。在上 述形成聚合物網路的方法中等之進行光照射的步驟（參見第2圖（C)) 中使用選擇性地使光通過的遮罩1〇。可任意設定遮罩1〇中遮光部分 的圖形’例如既可為具有沿一方向延伸的多個線狀遮光部分的圖形（線 狀圖形）’亦可為將沿兩方向延伸的多個線狀遮光部分重合而成的二維 網格狀圖形（矩_形）。隔著這種遮罩1G進行光照射，便如第3圖 (B)所不，在液晶層3内與遮罩1〇的透光部分對應的位置形成聚合 物牆（聚合物壁）6 〇並且還可以在使用遮罩1〇進行光照射之後，在 不使用遮罩1G的情況下進—步對液晶層3整體進行光照射。 ，第一4圖是表示逆TN魏晶元件的構造例的剖關。帛4圖所示 的液晶=件具有在第1基板（上側基板）51與第2基板（下側基板） 55之間有液Ba層59的基本構造。在第1基板51的外側配置有第】 偏光板61 ’在第2基板55的外側配置有第2偏光板62。以下進一步 詳細說明液晶το件的結構。並且對於密封液晶層59周圍的密封材料等 構件省略圖示和說明。 第1基板51和第2基板55分別為例如玻璃基板、塑膠基板等透 明基板。如圖所示，第i基板51和第2基板55彼此的一個面對向， 並以預疋間隙（例如數μηι)貼合。此外’雖省略特制圖示，然而也 可以在任一基板上形成薄膜電晶體等切換元件（開關元件）。 液晶層59設置於第1基板51與第2基板55彼此之間。構成液晶 層59的液晶材料的介電常數各向異性Δε為正（齡0)。在液晶層59 圖示出的粗線示意性表示未紐晶層59施加電㈣初始狀態下的液 201224594 晶分子的配向方位。液晶層59含有藉由上述方法形成的聚合物牆6〇。 第1電極52設置於第1基板51的一面側。另外，第2電極56設 置於第2基板55的一面側。第i電極52和第2電極56分別藉由例如 適當對銦錫氧化物（ITO)等透明導電膜進行圖案化而構成。 配向膜53以覆蓋第1電極52的方式設置於第i基板51的一面 側。另外，配向膜57以覆蓋第2電極56的方式設置於第2基板55的 一面側。 第5圖是用於說明用作本實施方式之逆TN型液晶元件的評定指 標的閾值電壓和銳利度的定義的圖。設液晶元件在未施加電壓時的穿 透率為100%，設提高施加電壓直至穿透率不再變化時的值為〇。/(^此 時，設穿透率為90%的電壓值為乂如，穿透率為1〇%的電壓值為Vi〇， 則能夠使用這些如下表現閾值電壓和銳利度。 閾值電壓=V9〇 銳利度V10/V90 通常閾值電壓和銳利度均為值愈小則可評定為該液晶元件的電光 學特性愈優良。 下面說明幾個上述逆TN型液晶元件的實施例。 (實施例1) 依以下條件製作實施例1的液晶元件，並評定其特性。首先準備 兩塊附有ΙΊΌ膜的玻璃基板’將其洗淨並乾燥。然後對各玻璃基板的 表面塗佈配向材料。作為配向材料，係適當使用可賦予液晶分子1度 〜2度的預傾角的水平配向材料。將一玻璃基板的配向材料煅燒對 其=施摩擦配向處理。此後在該玻璃基板上散佈間隙控制材料，再印 刷密封材料。使用粒徑為4μιη的物質作為間隙控制材料。又對另一玻 ^基板般燒配向材料’對其實施摩擦配向處理。此後將兩玻璃基板貼 合而形成液晶胞’並對其注入液晶材料。關於兩塊玻璃基板的貼合， 係使對各個玻璃基板所進行之摩擦配向處理的方向彼此夾卯度。又， 作為液晶材料係使用Merck股份有限公司製zu_2293。 ^有cb15作為旋光性材料。旋光性材料的添加量係設定為 度d與旋光性間距p〇之比d/p0 4 〇 2。又對液晶材料添加紫外線硬 201224594 化尘樹月曰。紫外線硬化型樹脂的添加量為4wt%、5^%或此三種 模式。在注入液晶材料之後將液晶胞密封，透過施加電壓使液晶層的 配向狀態從初始狀態的擴散扭轉狀_移到反婦狀態，然後對紫外 線硬化型樹脂進行紫外線照射。第6圖示出用於紫外線照射的遮罩的 結構。在本實蘭巾’使用具有®示之線狀圖案的遮罩進行紫外線照 射2次。在第丨次照射時和第2次照射時將遮罩方向實質上旋轉9〇度， 即線狀圖案的長度方向在第1二欠照射時和第2二欠照射時係實質上垂 直。如圖所示，遮罩的線狀圖形的線寬度實質上為15_，且線間距 為20μπι。又紫外線的波長為365nm，照射強度為4〇mW/cm2，在改變 遮罩方向的前後以該照射強度各進行3次的3〇秒照射。此時，在各次 紫外線照射之前進行用於使液晶層轉移到反扭曲狀態的電壓施加。電 壓施加條件例如為施加15V左右的電壓1〇秒、或間歇性施加15v左 右的電壓2、3次，由此在液晶層内便形成二維網格狀的聚合物牆。 第7圖是表示實施例1之液晶元件的顯微鏡觀察像的圖。圖示的 液晶元件添加有4 wt%的紫外線硬化型樹脂。圖中觀察為黑色網格狀的 部分即為聚合物牆；白色分布者則為間隙控制材料。液晶元件的偏光 板（P，A)的吸收軸如圖所示配置為構成實質上45度角的狀態。可確 認藉由形成聚合物牆而使得反扭曲狀態得以穩定。第8圖示出實施例 1的液晶元件的電光學特性（V-T特性）的測定結果（紫外線硬化型樹 脂的添加量為4wt〜6wt%的樣本）。若除去觀察到磁滯（hysteresis) 之4wt°/〇的樣本不論’而用5wt%和6wt%的各樣本進行比較，則5wt% 的樣本的銳度較為優良。 (實施例2) 以與上述實施例1相同的條件製作液晶元件，並評定其特性。其 中以下條件與實施例1不同。在本實施例中，d/p〇的值為〇2或〇4， 紫外線硬化型樹脂的添加量為4评1;%、5^1:%、6\¥1%、7\^%這四種模式。 另外’在本實施例中使用具有網格狀（矩陣狀）的圖形的遮罩進行紫 外線照射。第9圖示出本實施例中用於紫外線照射的遮罩的結構。μ 如圖所示，遮罩的網格狀圖形的線寬度實質上為18〇μηι，且線間 距為20μηι。另外，紫外線的波長為365nm，照射強度為8〇mW/cm2。 8 201224594 、、射強度讀次1刀鐘重複曝光時間4次 去除遮罩，進行1分鐘的曝光（整面昭 遮罩曝先最後 推杆曰整面·、、、射）。此時，在紫外線照射之前 進订用於使液Ba層轉移 左右的電壓K)秒、或間歇性施加15V左右的電壓H如 由此在液晶層内便形成一維網格狀的聚合物牆。 第=圖是表示實施例2之液晶元件的^微鏡觀察像的圖。圖示的 係設_為0.2且添加有細％的紫外線硬化型樹脂。圖中觀 2白_格狀的部分即為聚合物牆。液Μ件的偏光板（p，A)的吸 收軸如圖所示呈實質上夾20度角的狀態，且—偏光板（a)的吸收轴 =置為與聚合物牆的-個延伸方向實f±平行1確認藉由形成聚合 =牆而使得反扭轉狀態得以穩定。第„圖示纽改變該樣本的液晶元 件以及紫外線硬化型樹㈣添加量的樣本之各自的絲學躲（ν·τ 特性）的測定結果。並且在第U圖中表示為「ps前上升」、「％前下 降」者係形錢合物牆前樣本的v_n如_示，在形成聚合物 牆前的樣本中在v-τ特性中觀察到磁滯。 曰第12圖是表示實施例2之液晶元件的顯微鏡觀察像的圖。圖示的 液晶元件係設d/pO為0.4且添加有4wt〇/0的紫外線硬化型樹脂。圖中觀 察為白色網格狀的部分即為聚合物牆。液晶元件的偏光板（p,A)的吸 收轴如圖所示呈實質上夾1〇度角的狀態，並配置為—偏光板（A)的 吸收軸與聚合物牆的一延伸方向實質上平行。可確認藉由形成聚合物 牆而使得反扭轉狀態得以穩定。第13圖示出僅改變該樣本的液晶元件 以及紫外線硬化型樹脂的添加量的樣本各自的電光學特性（ν_τ特性） 的測定結果。此外，在第13圖中表示為rps前上升」、「ps前下降」 者係形成聚合物牆前樣本的V-Τ特性。如圖所示，在形成聚合物牆前 的樣本中在V-Τ特性中觀察到磁滞。 實施例2的液晶元件的閾值與習知TN型液晶元件實質上等同， 具體是1.58V(伏）左右。另外，對於銳利度能在最佳條件下獲得132 的值’相比習知TN型液晶元件係大幅改善。此處獲得的銳利度的1.32 的值表示出能獲得實質上1/12工作週期（duty cycle)以上的被動矩陣 (passive matrix ’單純矩陣simpie matrix )驅動，能夠大幅擴大習知以 201224594 1/4或1/8工作週期為限的TN型液晶元件的適用範圍。此外，銳利度、 閾值的定義係如上所述。 再者’本發明不限於上述内容，能夠在本發明主旨範圍内進行各 種變形並加以實施。例如上述内容中為形成聚合物牆而例示光硬化型 樹脂，但也可以使用熱硬化型樹脂。另外，在上述内容中，對於d/p〇 作為較佳係例舉所謂0.2、〇·4的值，惟d/pO不限於這些數值。本案發 明人根據預備試驗等進行研究，確認有d/p〇的值愈小則銳利度愈差之 趨勢’且可達成銳利度改善之d/p〇的下限值為〇.〇4。 【圖式簡單說明】 第1圖是示意性表示逆TN型液晶元件的動作的示意圖； 第2圖是概要性說明在液晶層内形成聚合物網路的方法（高分子 穩定法）的圖； 第3圖是說明在液晶層形成聚合物牆的方法的圖； 第4圖是表示逆TN型液晶元件的構造例的剖面圖； 第5圖是用於說明閾值電壓與銳利度的定義的圖； 第6圖是表示用於實施例〗之紫外線照射的遮罩的結構的圖； 第7圖是表示實施例1之液晶元件的顯微鏡觀察像的圖； 第8圖是表示實施例1之液晶元件的電光學特性的測定結果的圖； 第9圖是表示用於實施例2之紫外線照射的遮罩的結構的圖； 第1〇圖是表示實施例2之液晶元件的顯微鏡觀察像的圖； 第11圖是表示實施例2之液晶元件的電光學特性的測定結果的 圖， 第12圖是表示實施例2之液晶元件的顯微鏡觀察像的圖；以及 第13圖是表示實施例2之液晶元件的電光學特性的測定結果的 圖。 、’。 【主要元件符號說明】 1 上側基板 2 下側基板 201224594 3 液晶層 3a 液晶分子 3b 液晶性單體 4 上側電極 5 下側電極 6 聚合物牆 10 遮罩 51 第1基板 52 第1電極 53、 57配向膜 55 第2基板 56 第2電極 59 液晶層 60 聚合物牆 61 第1偏光板 62 第2偏光板201224594 VI. Description of the Invention: [Technical Field of the Invention] The present invention relates to an improved technique relating to electro-optical characteristics of a liquid crystal element. [Prior Art] In the liquid crystal display disclosed in Japanese Patent Publication No. 251G15G (Patent Document υ), the liquid crystal molecules are twisted and aligned in the following rotation direction to improve the electro-optical characteristics. In the respective base directions of the pair of substrates to be arranged (the first rotation direction (first rotation direction) in the opposite direction (first rotation direction) (first example 1). This liquid crystal display device (liquid crystal element) In addition, Japanese Patent Laid-Open No. 2007-293278 (Patent Document 2) discloses a liquid helium element which is added with a knob (four) and is trained. The material is such that the liquid crystal molecules are oriented in the opposite direction (the second rotation direction) of the direction (the m-th rotation direction) of the opposite direction of the alignment process of the opposite substrate (the second rotation direction). The pseudo-rotation direction twists the alignment to increase the deformation in the liquid crystal layer, and the threshold voltage is driven at a low voltage (Previous Example 2). Further, the following technique is disclosed in Japanese Laid-Open Patent Publication No. Hei No. 5 (Patent Document 3). The money is in the initial state of the splaytwlst alignment, and when the longitudinal electric field is applied once, it is the reverse TN type liquid crystal element which is reversely twisted (previous example 3). The reverse torsional alignment state of the display device is unstable. By applying a higher electric current to the liquid positive layer, a reverse torsional alignment state can be obtained, but there is a problem that the state is shifted to the forward torsional alignment state with the passage of time. The liquid crystal element yarn of the previous example 2 has the advantage of lowering the threshold voltage as described above, but the domain voltage is then turned to the right) to the forward alignment state, and the threshold voltage is increased instead of the reverse TM type liquid crystal element in the previous example 3. For example, the sharpness (8_Gu) in the previous example 3 is preferably about 1.7, and further improvement is required. [Patent Document 1] Japanese Patent No. 2510150 Publication No. 201224594 [Patent Document 2 [Patent Document 3] Japanese Laid-Open Patent Publication No. 2010-186045 [Abstract] One of the objects of the specific aspect of the present invention is to provide an improvement A liquid crystal element of one embodiment of the present invention is characterized in that: (a) the i-th substrate and the second substrate are characterized in that the liquid crystal element of one embodiment of the present invention is improved in stability. Each of the surfaces has an alignment treatment and is disposed opposite to each other; (b) a liquid crystal layer disposed between one surface of the first substrate and one surface of the second substrate; The wall material is disposed in the upper layer along the layer thickness direction, and (4) the direction of the alignment treatment of the i-th substrate and the second substrate is relatively set so as to easily cause the liquid crystal molecules of the liquid crystal layer to be twisted in the first rotation direction. In the i-th alignment state, U) the liquid crystal layer contains an optically active material and has an alignment state toward the first rotation torsion. The middle button (4) has a direction in which the liquid crystal molecules are twisted in a second rotation direction opposite to the rotation direction of the upper one. nature. According to the above configuration, by guiding the polymer wall to the liquid crystal layer, the alignment state (reverse twist state) in which the first direction is twisted can be stably maintained. For example, a photocurable resin is added to a liquid when a liquid crystal layer is formed, and a liquid crystal material is injected into the i-th substrate and the second substrate to apply a voltage or the like, and the layer is transferred from a diffusion-twisted state in an initial state to a luminescence irradiation, thereby being simple. Form a polymer wall. excellent. Therefore, according to the above configuration, it is possible to provide an improved retrograde alignment of the electro-optical properties, which is preferably a combination of a plurality of polymer walls, which can be combined in a plan view. - The step of increasing the steady-state resin irradiation light in the reverse-twisted state uses a grid-like light-shielding portion 4 to form a polymer wall having this face-like shape. ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ In the liquid crystal element, the liquid crystal molecules of the liquid crystal layer are, for example, substantially 90 degrees. Moreover, the twist angle can be about 9 degrees, for example, 8 degrees to 1 degree. [Embodiment] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Fig. 1 is a schematic view schematically showing the operation of the reverse TN type liquid crystal element. In the case of reverse crystallization, the basic structure of the liquid crystal element is the liquid crystal layer 3 having the upper substrate 丨 and the lower substrate 2 disposed opposite thereto, and the like. The surface of each of the upper plate i and the lower substrate 2 is subjected to an alignment process such as a rubbing alignment process (indicated by an arrow in the figure). The directions of the alignment processes are mutually intersected at an angle of about 90 degrees, and the upper substrate 丨 and the lower substrate 2 are disposed to face each other. The liquid crystal layer 3 is formed by injecting a nematic crystal material between the upper substrate 丨 and the lower substrate 2. The liquid crystal layer 3 is provided with a spin-on material using a crystallizing material sheet, and this optically active material acts to twist the liquid crystal molecules in a direction of azimuth thereof in a specific direction (the right direction of rotation in the example of the figure). When the distance between the upper substrate i and the lower substrate 2 (liquid cell thickness) is d and the optical rotation distance of the optically active material is p, the value of the ratio d/p is set to about 0.4, for example. In the initial state, the reverse TN type liquid crystal cell is in a diffusion twist state in which the liquid crystal layer 3 is diffused and aligned while being twisted. When a voltage exceeding the saturation voltage is applied to the liquid crystal layer 3 in the diffusion twist state, the liquid crystal molecules are transferred to a reverse twist state (uniform twist state) in which the liquid crystal molecules are twisted in the left rotation direction. In the liquid crystal layer 3 in the reverse twist state, the liquid crystal molecules in the bulk are inclined, so that the effect of lowering the driving voltage of the liquid crystal element can be exhibited. However, usually, such a reverse twist state is mostly unstable, and naturally shifts to a diffusion twist state as an initial state as time passes. Thus, the inventors of the present invention conceived to introduce a polymer network into the liquid crystal layer 3 in order to stabilize the alignment state of the liquid crystal layer 3. Fig. 2 is a view schematically showing a method of forming a polymer network in a liquid crystal layer (polymer stabilization method). As shown in FIG. 2(A), when the liquid layer 3 is formed between the upper substrate 1 and the lower substrate 2, a liquid crystal monomer 3b containing liquid crystal molecules such as a photocurable type (for example, an ultraviolet curing type) is used. Liquid crystal material. Next, as shown in FIG. 2(B), the current state of the liquid crystal layer 3 is applied to the liquid crystal layer 3 by applying a voltage to the upper electrode 4 and the lower electrode 5 provided on the upper substrate 1 and the lower substrate 2, respectively. Transfer to reverse twisting. Then, as shown in Fig. 2(c), the crystal layer 3 is irradiated with light (e.g., ultraviolet ray) while the liquid crystal layer 3 is maintained in the reverse twist state. Thereby, the liquid crystalline monomer 3b is molecularlyized, and a polymer network is formed in the liquid crystal layer 3. By forming such a polymer web:: the stability of the reverse twist state is improved, and the diffusion twist state which is not easily transferred to the initial state is shown. Fig. 3 is a view schematically illustrating a method of forming a polymer wall in a liquid crystal layer. The same components as those in the second embodiment are denoted by the same reference numerals, and the description thereof will be omitted. A mask for selectively passing light is used in the step of performing light irradiation (see Fig. 2(C)) in the above method of forming a polymer network. The pattern of the light-shielding portion in the mask 1 can be arbitrarily set, for example, a pattern (linear pattern) having a plurality of linear light-shielding portions extending in one direction, or a plurality of lines extending in both directions A two-dimensional grid pattern (moment_shape) in which the shading portions are overlapped. When the light is irradiated through the mask 1G, as shown in FIG. 3(B), a polymer wall (polymer wall) is formed in the liquid crystal layer 3 at a position corresponding to the light-transmitting portion of the mask 1〇. Further, after the light irradiation is performed using the mask 1 ,, the entire liquid crystal layer 3 is further irradiated with light without using the mask 1G. The first four-figure is a cross-sectional view showing a structural example of the reverse TN Wei-jing element. The liquid crystal material shown in Fig. 4 has a basic structure in which a liquid Ba layer 59 is present between the first substrate (upper substrate) 51 and the second substrate (lower substrate) 55. The second polarizing plate 62 is disposed outside the first substrate 51 with the second polarizing plate 61' disposed on the outer side of the second substrate 55. The structure of the liquid crystal τ member will be described in further detail below. Further, the illustration and description of the members such as the sealing material surrounding the liquid crystal layer 59 are omitted. Each of the first substrate 51 and the second substrate 55 is a transparent substrate such as a glass substrate or a plastic substrate. As shown in the figure, one of the i-th substrate 51 and the second substrate 55 faces each other and is bonded by a pre-twisting gap (for example, several μm). Further, although a special illustration is omitted, a switching element (switching element) such as a thin film transistor may be formed on any of the substrates. The liquid crystal layer 59 is provided between the first substrate 51 and the second substrate 55. The dielectric constant anisotropy Δ ε of the liquid crystal material constituting the liquid crystal layer 59 is positive (age 0). The thick line illustrated in the liquid crystal layer 59 schematically indicates the orientation of the liquid 201224594 crystal molecules in the initial state in which the non-kaln layer 59 is applied. The liquid crystal layer 59 contains the polymer wall 6 formed by the above method. The first electrode 52 is provided on one surface side of the first substrate 51. Further, the second electrode 56 is provided on one surface side of the second substrate 55. Each of the i-th electrode 52 and the second electrode 56 is formed by, for example, patterning a transparent conductive film such as indium tin oxide (ITO). The alignment film 53 is provided on one surface side of the i-th substrate 51 so as to cover the first electrode 52. Further, the alignment film 57 is provided on one surface side of the second substrate 55 so as to cover the second electrode 56. Fig. 5 is a view for explaining the definitions of the threshold voltage and the sharpness of the evaluation index used as the inverse TN type liquid crystal element of the present embodiment. It is assumed that the transmittance of the liquid crystal element when no voltage is applied is 100%, and the value obtained by increasing the applied voltage until the transmittance is no longer changed is 〇. /(^ At this time, if the voltage value of the transmittance of 90% is set to, for example, the voltage value of the transmittance of 1% is Vi〇, the threshold voltage and the sharpness can be expressed as follows. Threshold voltage = V9 〇 Sharpness V10/V90 Generally, the smaller the threshold voltage and the sharpness are, the better the electro-optical characteristics of the liquid crystal element can be evaluated. Several embodiments of the above-described inverse TN type liquid crystal element will be described below. (Embodiment 1) The liquid crystal cell of Example 1 was produced under the following conditions, and its characteristics were evaluated. First, two glass substrates with a ruthenium film were prepared, which were washed and dried, and then the surface of each glass substrate was coated with an alignment material. A horizontal alignment material capable of imparting a pretilt angle of 1 to 2 degrees to the liquid crystal molecules is suitably used. The alignment material of a glass substrate is calcined and subjected to rubbing alignment treatment. Thereafter, a gap control material is spread on the glass substrate, and then printed. A sealing material is used as a gap control material using a material having a particle diameter of 4 μm, and a rubbing alignment treatment is performed on another glass-like substrate, and then the two glass substrates are bonded together. The liquid crystal cell is injected into the liquid crystal material. The bonding of the two glass substrates is such that the direction of the rubbing alignment treatment performed on each of the glass substrates is clamped to each other. Further, as a liquid crystal material, Merck Co., Ltd. is used. Manufactured zu_2293. ^There is cb15 as the optically active material. The addition amount of the optically active material is set to the ratio of the degree d to the optical rotation distance p〇d/p0 4 〇2. Adding ultraviolet light to the liquid crystal material 201224594 The ultraviolet curable resin is added in an amount of 4 wt%, 5 %, or the like. After the liquid crystal material is injected, the liquid crystal cell is sealed, and the alignment state of the liquid crystal layer is shifted from the initial state to the reverse state by the application of a voltage. In the gynecological state, ultraviolet ray irradiation is applied to the ultraviolet curable resin. Fig. 6 shows the structure of the mask for ultraviolet ray irradiation. The ray towel is irradiated twice with ultraviolet rays using a mask having a linear pattern of ® The mask direction is substantially rotated by 9 degrees at the time of the second irradiation and the second irradiation, that is, the longitudinal direction of the linear pattern is at the time of the first two under-irradiation and the second-second illuminating It is substantially vertical. As shown in the figure, the line width of the masked line pattern is substantially 15_, and the line spacing is 20μπι. The wavelength of the ultraviolet light is 365nm, and the irradiation intensity is 4〇mW/cm2, changing the mask direction. Each of the irradiation intensity is irradiated three times for three sec seconds. At this time, voltage application for shifting the liquid crystal layer to the reverse twist state is performed before each ultraviolet ray irradiation. The voltage application condition is, for example, a voltage of about 15 V is applied. A polymer wall having a two-dimensional grid shape is formed in the liquid crystal layer by applying a voltage of about 15 volts for 2 or 3 times intermittently. Fig. 7 is a view showing a microscope image of the liquid crystal element of Example 1. The liquid crystal element shown in the figure is added with 4 wt% of an ultraviolet curable resin. In the figure, a black grid-like portion is a polymer wall, and a white distributor is a gap control material. The absorption axis of the polarizing plate (P, A) of the liquid crystal element is arranged to form a state of substantially 45 degrees as shown in the drawing. It can be confirmed that the anti-twist state is stabilized by forming a polymer wall. Fig. 8 shows the measurement results of the electro-optical characteristics (V-T characteristics) of the liquid crystal element of Example 1 (the amount of the ultraviolet curable resin added is 4 wt% to 6 wt%). If a sample of 4 wt/min observed hysteresis was removed, and 5 wt% and 6 wt% of each sample were compared, the sharpness of the 5 wt% sample was excellent. (Example 2) A liquid crystal element was produced under the same conditions as in the above Example 1, and its characteristics were evaluated. The following conditions are different from those of the first embodiment. In the present embodiment, the value of d/p〇 is 〇2 or 〇4, and the amount of ultraviolet curable resin added is 4 to 1; %, 5^1:%, 6\¥1%, 7\^% Four modes. Further, in the present embodiment, ultraviolet rays are irradiated using a mask having a grid-like (matrix-like) pattern. Fig. 9 shows the structure of a mask for ultraviolet irradiation in the present embodiment. μ As shown in the figure, the line width of the masked grid pattern is substantially 18〇μηι and the line spacing is 20μηι. Further, the ultraviolet light had a wavelength of 365 nm and an irradiation intensity of 8 〇mW/cm 2 . 8 201224594 , and the intensity of the reading is 1 knives and the re-exposure time is 4 times. The mask is removed and exposed for 1 minute (the entire surface of the mask is exposed, the last putter, the entire surface, and the shot). At this time, before the ultraviolet irradiation, a voltage for shifting the left and right sides of the liquid Ba layer for K) or a voltage H of about 15 V is intermittently applied, thereby forming a one-dimensional grid-like polymer wall in the liquid crystal layer. . Fig. = Fig. is a view showing a micromirror observation image of the liquid crystal element of Example 2. The illustration is shown in Fig. 0.2, and a fine % ultraviolet curable resin is added. In the figure, the white _ grid-shaped part is the polymer wall. The absorption axis of the polarizing plate (p, A) of the liquid helium member is substantially at a 20-degree angle as shown, and the absorption axis of the polarizing plate (a) is set to be an extension direction of the polymer wall. Real f±parallel 1 confirms that the reverse twist state is stabilized by forming a polymerization=wall. The measurement result of the silkworm hiding (ν·τ characteristic) of each of the liquid crystal elements of the sample and the sample of the ultraviolet curable tree (four) is added, and is shown as "rising before ps" in the U-picture. The "pre-% drop" is the v_n of the sample in front of the wall, and the hysteresis is observed in the v-τ characteristic in the sample before the formation of the polymer wall. Fig. 12 is a view showing a microscope observation image of the liquid crystal element of Example 2. The liquid crystal element shown in the drawing is an ultraviolet curable resin having d/pO of 0.4 and 4 wt%/0 added thereto. The portion of the figure observed as a white grid is the polymer wall. The absorption axis of the polarizing plate (p, A) of the liquid crystal element is substantially clipped at a 1 degree angle as shown in the drawing, and is arranged such that the absorption axis of the polarizing plate (A) and the extending direction of the polymer wall are substantially parallel. It was confirmed that the reverse twist state was stabilized by forming a polymer wall. Fig. 13 shows the measurement results of the electro-optical characteristics (ν_τ characteristics) of the samples in which only the liquid crystal element of the sample and the addition amount of the ultraviolet curable resin were changed. In addition, in Fig. 13, the V-Τ characteristic of the sample before the formation of the polymer wall is shown as "rise before rps" and "fall before ps". As shown, hysteresis was observed in the V-Τ characteristics in the sample before forming the polymer wall. The threshold value of the liquid crystal element of Example 2 is substantially equivalent to the conventional TN type liquid crystal element, specifically about 1.58 V (volt). Further, the value of 132 which can be obtained under the optimum conditions for the sharpness is greatly improved as compared with the conventional TN type liquid crystal element. The value of 1.32 of the sharpness obtained here indicates that a passive matrix (simple matrix simpie matrix) drive capable of obtaining a substantially 1/12 duty cycle or more can be greatly expanded to 201224594 1/4. Or the applicable range of TN type liquid crystal elements with a 1/8 duty cycle. In addition, the definition of sharpness and threshold is as described above. Further, the present invention is not limited to the above, and various modifications can be made and implemented within the spirit and scope of the invention. For example, in the above description, a photocurable resin is exemplified to form a polymer wall, but a thermosetting resin may also be used. Further, in the above description, d/p〇 is preferably a value of 0.2, 〇·4 as a preferred example, and d/pO is not limited to these values. The inventors of the present invention conducted research based on preliminary tests and confirmed that the smaller the value of d/p〇 is, the worse the sharpness is, and the lower limit of d/p〇 which can achieve sharpness improvement is 〇.〇4. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic view schematically showing the operation of an inverse TN liquid crystal element; Fig. 2 is a view schematically showing a method of forming a polymer network in a liquid crystal layer (polymer stabilization method); Fig. 3 is a view for explaining a method of forming a polymer wall in a liquid crystal layer; Fig. 4 is a cross-sectional view showing a configuration example of a reverse TN type liquid crystal element; and Fig. 5 is a view for explaining definitions of threshold voltage and sharpness Fig. 6 is a view showing the structure of a mask for ultraviolet irradiation of the embodiment; Fig. 7 is a view showing a microscope observation image of the liquid crystal element of the first embodiment; and Fig. 8 is a view showing the liquid crystal of the embodiment 1. FIG. 9 is a view showing a configuration of a mask used for ultraviolet irradiation in the second embodiment; and FIG. 1 is a view showing a microscope observation image of the liquid crystal element of the second embodiment; FIG. 11 is a view showing measurement results of electro-optical characteristics of the liquid crystal element of Example 2, FIG. 12 is a view showing a microscope observation image of the liquid crystal element of Example 2, and FIG. 13 is a view showing Example 2; Electro-optic light of liquid crystal element The measurement result of FIG. , '. [Description of main component symbols] 1 Upper substrate 2 Lower substrate 201224594 3 Liquid crystal layer 3a Liquid crystal molecules 3b Liquid crystal monomer 4 Upper electrode 5 Lower electrode 6 Polymer wall 10 Mask 51 First substrate 52 First electrode 53, 57 Alignment film 55 second substrate 56 second electrode 59 liquid crystal layer 60 polymer wall 61 first polarizing plate 62 second polarizing plate