200819843 九、發明說明 【發明所屬之技術領域】 本發明係關於在偏光子的單面將具有液晶化合物之塗 覆層的光學補償薄膜予以貼合的複合偏光板，及使用其之 液晶顯示裝置。本發明亦又關於製造上述構造之複合偏光 板的方法及製造其所用之光學補償薄膜的方法。詳言之， 係關於改善上述構造之複合偏光板或構成其之光學補償薄 膜之耐水性的技術。 【先前技術】 近年來，低消耗電力、低電壓動作、質量輕、薄型之 液晶顯示器已急速普及作爲行動電話、攜帶資訊終端、電 腦用之監視器、電視等之資料用顯示裝置。隨著液晶技術 的發展，已提案各式各樣型式的液晶顯示器，並且持續解 決回應速度和對比度、狹視野角之液晶顯示器的問題點。 液晶顯示器有TN ( Twisted Nematic :扭轉向列）、 STN ( Super Twisted Nematic :超扭轉向歹[J ) 、VA (BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite polarizing plate in which an optical compensation film having a coating layer of a liquid crystal compound is bonded to one surface of a polarizer, and a liquid crystal display device using the same. The present invention also relates to a method of manufacturing the composite polarizing plate of the above configuration and a method of producing the optical compensation film used therefor. More specifically, it relates to a technique for improving the water resistance of a composite polarizing plate or an optical compensation film constituting the above structure. [Prior Art] In recent years, liquid crystal displays having low power consumption, low voltage operation, light weight, and low thickness have been rapidly popularized as display devices for data such as mobile phones, portable information terminals, monitors for computers, and televisions. With the development of liquid crystal technology, various types of liquid crystal displays have been proposed, and the problems of liquid crystal displays that respond to speed and contrast and narrow viewing angles are continuously solved. The liquid crystal display has TN (Twisted Nematic), STN (Super Twisted Nematic: Super Twisted Nematic), VA (
Vertical Alignment:垂直配向） 、IPS ( In-plane Switching :橫電場）等各式各樣的方式，但於此些方式中 ，因爲液晶分子爲具有相位差値所引起的漏光、和偏光板 中斜視時的軸角度不齊等，而分別存在成爲弱點之視野角 的狹窄方向（方位角）。作爲放大此類弱點視野角的方法 ，乃廣泛採用以相位差薄膜對於液晶元件和偏光板進行光 學補償的方法。如此之相位差薄膜或光學補償膜爲根據液 -5- 200819843 晶元件內之液晶的相位差値、配向方向、液晶分子的驅動 方式等，而改變最適之種類，故使用許多種類之物質。 此類相位差薄膜或光學補償薄膜之一者，爲於透明支 撐體上將液晶化合物塗層表現光學特性之類型者。通常， 於透明支撐體上塗佈液晶化合物而製作，但於許多情況， 爲了令此液晶化合物於某特疋方向上配向，乃於透明支撐 體上預先形成配向膜。例如，於特開平9 - 1 7 9 1 2 5號公報 (專利文獻1 )中，記載於透明支撐體上設置配向膜作成 附有配向膜的支撐體，並於此配向膜上設置圓盤狀，化合 物所構成的光學異向層（光學補償層），作成光學補償薄 片。 配向膜的材質必須考慮配向特性和塗佈性、光學特性 、耐久性等而選擇適切的物質，特別由配向特性和塗佈性 方面而言，亦多選擇對於水頗無耐性的材料，換言之係由 親水性材料中選出。例如，於上述專利文獻1中，推薦以 聚乙烯醇作爲配向膜。配向膜和塗覆層以對於水無耐性之 材料所構成的情形中，於含有大量水分之環境下的耐久性 不足，例如，於高溫·高濕條件下對液晶顯示器產生不適 。具體而言，於水的影響下，任一層喪失充分的密黏力時 ，經由構成偏光板之其他層的熱所造成的伸縮、和吸放濕 所造成之伸縮等之外部應力，則發生層間剝離和此層本身 的破壞。 若進一步詳細說明，發現於三乙醯纖維素等之纖維素 系樹脂所構成的透明支撐體上形成親水性的配向膜，再於 -6- 200819843 其上將形成液晶化合物之塗覆層的光學補償薄膜’接黏至 偏光子的單面，並且於偏光子的多面接黏通常之三乙醯纖 維素所構成之透明保護薄膜的偏光板，曝露於高溫高濕條 件時，親水性的配向膜受到水分所影響’且於偏光板端邰 配向膜與各層間的密黏力降低，故在透明支撐體/配向膜/ 液晶化合物之塗覆層的任一界面引起浮起，並且以此處爲 起點引起隧道狀的空隙往偏光板內部進行的現象。以下’ 將此種現象稱爲鑽隧道。圖5中，示出將發生鑽隧道之偏 光板的表面端部予以放大的照片。於此圖中，可知右側爲 偏光板之端，並且由此處成長出許多的隧道20。 〔專利文獻1〕特開平9- 1 79 1 25號公報 【發明內容】 (發明所欲解決之課題） 於是，本發明之課題爲在於纖維素系樹脂所構成之透 明支撐體上形成配向膜，再於其上形成液晶化合物之塗覆 層的光學補償薄膜、或者將此透明支撐體側貼合至偏光子 之複合偏光板中，即使此光學補償薄膜含有對於水之耐性 低之層時，亦可防止濕熱條件下之層間剝離和層破壞，並 且改良其耐水性。硏究之結果發現，對於此類對水耐性低 之構材施以熱處理，提高耐水性，取得不會發生如上述不 適之耐久性優良的複合偏光板，並且達到完成本發明。 (解決課題之手段） -7- 200819843 即’若根據本發明，則提供於纖維素系樹脂所構成之 透明支撐體上形成配向膜，再於其上形成液晶化合物之塗 覆層的光學補償薄膜，爲以其透明支撐體側貼合至偏光子 之單面而成的複合偏光板，此光學補償薄膜爲以裁斷成2 公分X5公分的長方形，並將液晶化合物的塗覆層作爲內側 ，以圓周爲5公分且高度爲2公分之圍成圓筒的狀態於6 0 °C溫水中浸漬60分鐘時所發生的氣泡密度爲未滿100個 /cm2般施以熱處理的複合偏光板。 於上述之複合偏光板中，光學補償薄膜爲如上述，將 2公分x5公分之長方形以液晶化合物之塗覆層爲內側般， 以圓周爲5公分且高度爲2公分之圍成圓筒的狀態於60 °C 溫水中浸漬60分鐘時所發生的氣泡密度爲60個/cm2以下 般施以熱處理爲佳。 於此複合偏光板中，於偏光子之光學補償薄膜貼合面 的反側面，貼合透明保護薄膜，則可將偏光子的兩面作成 保護的狀態。此情況之透明保護薄膜，以偏光子反側施以 表面處理爲佳。此透明保護薄膜例如以三乙醯纖維素等之 纖維素系樹脂所構成。 另一方面，光學補償薄膜中的配向膜，多以親水性之 樹脂所構成，例如，以聚乙烯醇系樹脂所構成。構成光學 補償薄膜之液晶化合物的塗覆層，可爲含有圓盤狀液晶的 光學補償層。此光學補償層爲由具有圓盤狀構造單位之液 晶化合物所構成之具有負的雙折射層，此圓盤狀構造單位 的圓盤面爲對於透明支撐體面傾斜，而圓盤狀構造單位的 -8 - 200819843 圓盤面與透明支撐體面所成之角度爲於光學補償層的厚度 方向上變化所構成。此時，圓盤狀構造單位之圓盤面相對 於透明支撐體面所成之角度，於光學補償層之厚度方向中 隨著由光學補償層之透明支撐體側之距離增加而增加爲佳 〇 於構成光學補償薄膜之液晶化合物的塗覆層外側設置 感壓式接黏劑層，可貼合至液晶元件。 又，若根據本發明，則亦提供具備上述任一種複合偏 光板和液晶元件，並且於液晶元件的一面令上述的複合偏 光板以其光學補償薄膜側透過感壓式接黏劑層予以層合的 液晶顯示裝置。 更且，若根據本發明，亦提供如上述改善耐水性之複 合偏光板的製造方法，此方法爲於纖維素系樹脂所構成之 透明支撐體上形成配向膜，再於其上將形成液晶化合物之 塗覆層的光學補償薄膜，以其透明支撐體側貼合至偏光子 並製造複合偏光板時，關於前述光學補償薄膜，使用裁斷 成2公分X5公分之長方形，並以液晶化合物之塗覆層作爲 內側，以圓周爲5公分且高度爲2公分之圍成圓筒的狀態 於60 °C溫水中浸漬60分鐘時，以100個/cm2以上之密度 發生氣泡的底版，且對於此光學補償薄膜，以同一條件於 溫水中浸漬時發生氣泡的密度爲未滿100個/cm2般於40 °C以上1 5 0 °C以下之溫度下至少1 0分鐘的熱處理施行至底 版，或者施行至前述光學補償薄膜貼合至偏光子後的複合 偏光板。 -9 - 200819843 又，若根據本發明，則亦提供使用於上述 之耐水性被改善之光學補償薄膜的製造方法， 於纖維素系樹脂所構成之透明支撐體上形成配 其上將形成液晶化合物之塗覆層的光學補償薄 用裁斷成2公分χ5公分之長方形，並以液晶化 層作爲內側，以圓周爲5公分且高度爲2公分 的狀態於60°C溫水中浸漬60分鐘時，以1〇〇 之密度發生氣體的底版，以同一條件於溫水中 氣泡的密度爲未滿100個/ cm2般，於4(TC以J 之溫度下至少施以1 0分鐘的熱處理。於此方 理的溫度爲60°C以上、120°C以下爲更佳。 (發明之效果） 本發明之複合偏光板爲構成其的光學補償 於含有親水性層，例如含有親水性配向膜之情 制水分對其的影響，例如，將此複合偏光板放 濕之氛圍氣時，可防止其光學補償薄膜的層間 壞，更且可抑制其伴隨之鑽隧道的發生。配置 板的液晶顯示裝置，即使曝露於高溫·高濕條 保持安定的顯示品質。 又，根據本發明之複合偏光板的製造方法 薄膜的製造方法，則可確實製造如上述改善耐 偏光板、或使用其之耐水性已被改善的光學補 複合偏光板 此方法爲關 向膜，再於 膜，對於使 合物之塗覆 之圍成圓筒 個/cm2以上 浸漬時發生 .1 5 0 °C以下 法中，熱處 薄膜，即使 形，亦可抑 置於高溫高 剝離和層破 此複合偏光 件下，亦可 及光學補償 水性的複合 償薄膜。 -10- 200819843 【實施方式】 以下，亦一邊參照適當圖面，一邊說明本發明之具體 的實施形態。本發明之複合偏光板之層構成例於圖1中以 剖面模式圖表示。圖1之（A )爲示出基本的層構成，此 複合偏光板爲於纖維素系樹脂所構成之透明支撐體3上形 成配向膜4，再於其上令形成液晶化合物之塗覆層5的光 學補償薄膜2，以其透明支撐體3側貼合至偏光子1之單 面所構成。於偏光子1之光學補償薄膜2貼合面之反側面 ，貼合透明保護薄膜7爲佳。又，如圖1之（B )所示般 ，此透明保護薄膜7爲其外側，即與偏光子1的反側，具 有表面處理層8爲佳。圖1之（B)，因爲除了於透明保 護薄膜7的外側設置表面處理層8以外，與圖1之（A ) 相同，故於（A )相同部分加以相同符號，並且省略重複 說明。於光學補償薄膜2之外側，即液晶化合物之塗覆層 5的表面，設置用以貼合至液晶元件的感壓式接黏劑層9 〇 首先，一邊參照圖1，一邊對於各層依序說明。 偏光子1爲透過具有指定方向之振動面的直線偏光， 並且吸收與其垂直方向具有振動面之直線偏光的光學元件 。具體而言，可列舉於聚乙烯醇系樹脂薄膜吸黏配向二色 性色素的薄膜。吸黏配向碘作爲二色性色素的碘系偏光子 、和吸黏配向二色性有機染料作爲二色性色素的染料系偏 光子均可使用。 構成光學補償薄膜2的透明支撐體3爲以纖維素系樹 -11 - 200819843 脂所構成。纖維素系樹脂具體而言可列舉二乙醯纖維素和 三乙醯纖維素等之乙醯纖維素系樹脂，其中一般使用三乙 醯纖維素。 於透明支撐體3上形成的配向膜4，多以親水性樹脂 所構成，特別一般爲以聚乙烯醇系樹脂所構成。聚乙烯醇 系樹脂例如亦可爲導入烷基等之改質聚乙烯醇。 通常，於透明支撐體3上形成此類親水性樹脂所構成 的塗覆層，並將其表面予以摩擦處理，作成配向膜4。 液晶性化合物之塗覆層5，例如亦有向列液晶爲傾斜 配向者（由新日本石油股份有限公司所販售的“NH Film” 等），但一般爲將含有圓盤狀液晶的塗佈液予以塗覆，並 且配向的光學補償層。此光學補償層爲由具有圓盤狀構造 單位之液晶性化合物所構成之具有負的雙折射層，其圓盤 狀構造單位的圓盤面爲對於透明支撐體面傾斜，而此圓盤 狀構造單位之圓盤面與透明支撐體面所成之角度爲於光學 補償層的厚度方向上變化爲佳。於此形態中，圓盤狀構造 單位之圓盤面相對於透明支撐體面所成之角度，爲於光學 補償層之厚度方向中隨著由光學補償層之透明支撐體側的 距離增加而增加，所謂的混合配向亦爲有效。圓盤狀構造 單位之圓盤面相對於透明支撐體面所成之角度，例如，以 5度〜5 0度左右之範圍由透明支撐體側依序增加的構造。 於透明支撐體上形成配向膜及圓盤狀結晶之塗覆層的光學 補償薄膜具體例，可列舉由富士照相軟片（股）所販售之 “Wide Blue” Film (亦以 “WVFilm”表現）等。 -12- 200819843 於偏光子1的另一面貼合的透明保護薄膜7，可使用 自以往所使用之任意的透明樹脂薄膜。例如，可使用聚烯 烴、聚甲基丙烯酸甲酯、聚碳酸酯、聚對苯二甲酸乙二酯 、環狀烯烴系樹脂（原冰片烯系樹脂）等之薄膜、和三乙 醯纖維素和二乙醯纖維素等所代表之纖維素系樹脂的薄膜 。其中’較佳使用纖維素系樹脂，尤其以三乙醯纖維素之 薄膜。 於透明保護薄膜7之表面形成的表面處理層8，係用 以令偏光板應用於液晶顯示裝置時作爲顯示面側（辨視側 )，改良其物性所設置之層。 具體而言，可列舉用以改善表面之耐擦傷性等所設置 的硬塗層’用以防止外光回映和閃燦所設置的防眩層、用 以防止外光反射所設置的防止反射層，用以防止靜電發生 所設置的防止帶電層等。 硬塗層爲經由塗佈紫外線硬化型之硬塗樹脂，並且於 此處照射紫外線令其硬化的方法等則可設置。防眩層爲例 如塗佈已添加充塡劑的紫外線硬化型樹脂，並於此處照射 紫外線令其硬化，並且根據充塡劑出現凹凸的方法，令紫 外線硬化型樹脂以接觸浮雕模型的狀態照射紫外線，並且 硬化令凹凸出現的方法等則可設置。防止反射層爲經由令 金屬氧化物等以一層或數層澱積之方法等則可設置。又， 防止帶電層爲經由塗佈加入防止帶電劑的紫外線硬化型樹 脂，並於此處照射紫外線令其硬化之方法等則可設置。 於光學補償薄膜2的外側，即液晶化合物之塗覆層5 -13- 200819843 的表面，可設置用以貼合至液晶元件的感壓式接黏劑層9 。此感應式接黏劑層10爲以丙丨希酸系等之亦稱爲黏著齊11 之感壓式接黏劑型式已知之黏著性樹脂所構成。 如上述所構成之複合偏光板中’如先前背景技術項所 說明般，曝露於高溫高濕條件時’配向膜’特別爲親水性 之配向膜受到水分影響’令配向膜與各層間的密黏力降低 ，故於透明支撐體/配向膜/液晶化合物之塗覆層的任一者 界面引起浮起，並且以此爲起點往偏光板內部進行隧道狀 之空隙的現象，即引起鑽隧道。若根據本發明者等人之調 查，於使用具有三乙醯纖維素薄膜所構成之透明支撐體上 形成聚乙烯醇系樹脂所構成的配向膜，再於其上形成圓盤 狀液晶之塗覆層，以圓盤狀液晶的圓盤面爲相對於透明支 撐體面傾斜，且此圓盤面與透明支撐體面所成之角度爲於 圓盤狀液晶塗覆層之厚度方向中，隨著透明支撐體側之距 離增加而增加之構造之富士照相軟片（股）製之光學補償 薄膜“WV-SA”時，上述鑽隧道的發生顯著。 此類鑽隧道的發生認爲係起因於配向膜之聚乙烯醇系 樹脂的親水性，且其耐水性爲不充分爲其原因之一。於定 量性判斷此類耐水性低之構材的耐水性上，發現如下述之 方法爲有效的。 即，於圖2之（A )中以平面圖所示般，將對象薄膜 (光學補償薄膜）裁斷成2公分x5公分之長方形。其次， 將此長方形，以液晶化合物之塗覆層爲內側般捲起，作成 圓周爲5公分且高度爲2公分的圓筒。此圍住之狀態於圖 -14- 200819843 2之（B )中以斜視圖表示。以圍住 (寬2公分之二個端部爲接合時）1( 以固定。以此狀態於6 〇 °C之溫水中浸 此時，耐水性差的樣品中，發生 氣泡的原因爲水令三乙醯纖維素/配[ί 密黏力降低，故於層間發生浮起。因 性高的光學補償薄膜，則頗不會發生， 於如上述之溫水浸漬試驗中發生 差的光學補償薄膜，其後，以通常之 作成複合偏光板之情形中，於高溫高 剝離發生隧道狀之浮起和剝落的可能> 爲了改善溫水浸漬試驗中發生許 提高光學補償薄膜的耐水性，發現對 熱處理則爲有效。於是，本發明中， 構成之透明支撐體3上形成配向膜4 化合物之塗覆層5的光學補償薄膜2 充分的光學補償薄膜2，施以熱處理 償薄膜2的耐水性。 圖3中，示出將如上述溫水浸漬 的光學補償薄膜表面，以倍率約1 0 燈觀察時的照片。又，於圖4中，示 幾乎完全未發生氣泡的光學補償薄膜 倍的放大鏡罩以螢光燈觀察時的照片 爲透明，故由任一側察看均觀察到氣 狀態接合的樣品端部 )，以接黏膠帶12予 漬60分鐘。 許多氣泡。發生此類 3膜/液晶塗覆層間之 此，若爲對於水之耐 此類氣泡。 許多氣泡，且耐水性 步驟貼合至偏光子， 濕條件下，經由層間 丨生爲非常局。 多氣泡的現象，並且 此光學補償薄膜施以 對於纖維素系樹脂所 ，再於其上形成液晶 ，特別爲耐水性不夠 ，則可改善此光學補 試驗中發生許多氣泡 倍的放大鏡罩以螢光 出將溫水浸漬試驗中 表面，以倍率約1 〇 。光學補償薄膜本身 包，圖3及圖4的照 -15- 200819843 片爲由透明支撐體側所觀察者。 其後，如上述於6 0 °C之溫水中浸漬6 0分鐘後，由溫 水中取出，並觀察光學補償薄膜之表面時，以100個/cm2 以上之密度發生氣泡的光學補償薄膜，將其貼合至偏光子 作成複合偏光板之情形中，若將高溫高濕條件下經由光學 補償薄膜的層間剝離易發生鑽隧道，且氣泡的密度降低， 則難發生此類鑽隧道。於是，於上述所示之溫水浸漬試驗 中以1 〇 〇個/cm2以上之密度發生氣泡時，判定爲耐水性低 者，且於相同之溫水浸漬試驗中僅以未滿100個/cm2之密 度發生氣泡時，判定爲耐水性高者。耐水性高之基準爲發 生氣泡的密度爲60個/cm2以下爲更佳。 改善光學補償薄膜之耐水性的熱處理爲於4 〇 °C以上 1 5 0 °C以下之溫度，進行1 0分鐘以上之時間爲佳。此時之 熱處理溫度爲 60 °C以上、120 °C以下爲佳。更且，熱處理 之時間爲3 0分鐘以上爲更佳。熱處理時間之上限並無特 別，由提高生產性及耐水性效果來看決定必要之時間。若 提高溫度則以相對短之時間完成，若降低溫度則必須以相 對長的時間。經由熱處理提高耐水性的理由，例如，認爲 因爲提高配向膜和塗覆層的交聯度故對於水變成難溶，但 詳細理由仍未查明。 此熱處理的時機爲接黏至偏光子前，即，即使將前述 的光學補償薄膜本身熱處理亦無妨，且於作成複合偏光板 後予以熱處理亦可。至少，作成偏光板方面以通常步驟所 加以的熱，並非本發明所謂之熱處理對象。即，本發明中 -16- 200819843 所謂的熱處理，係指與所謂「光學補償薄膜（透明保護薄 0旲）之驗化―與偏光子的接黏^形成感壓式接黏劑層」製 造偏光板之通常的步驟不同，主要爲提高含有液晶化合物 之塗覆層之光學補償薄膜的耐水性所設置的熱處理步驟。 因此，此熱處理爲至少於光學補償薄膜的單面，特別於液 晶化合物之塗覆層露出的狀態下施行爲佳。 如上述於本發明中，若改以參照圖1予以說明，則關 於纖維素系樹脂所構成之透明支撐體3上形成配向膜4， 再於其上形成液晶化合物之塗覆層5的光學補償薄膜2， 以其透明支撐體3側貼合至偏光子單面而成的複合偏光板 ’此光學補償薄膜2爲裁斷成2公分χ5公分之長方形，並 以液晶化合物之塗覆層5作爲內側，以圓周爲5公分且高 度爲2公分之圓筒圍住的狀態（參照圖2 )於60 °C之溫水 中浸漬60分鐘時發生的氣泡密度爲未滿1〇〇個/cm2般施 以熱處理所構成。 將圖1所示之複合偏光板與液晶元件組合作成液晶顯 示裝置上，以光學補償薄膜2側，透過感壓式接黏劑層9 貼合至液晶元件。 又’根據本發明之方法製造複合偏光板上，將纖維素 系樹脂所構成之透明支撐體3上形成配向膜4，再於其上 形成液晶化合物之塗覆層5的光學補償薄膜2，以其透明 支撐體3側貼合至偏光子丨製造複合偏光板時，關於其光 學補償薄膜2，使用裁斷成2公分x5公分之長方形，並以 液晶化合物的塗覆層5作爲內側，以圓周爲5公分且高度 -17- 200819843 爲2公分之圍成圓筒的狀態（參照圖2 )於60它之溫水中 浸漬60分鐘時，以1 〇〇個/cm2以上之密度發生氣泡的底 版，並且相對於此光學補償薄膜，以同一條件於溫水中浸 漬時發生氣泡的密度爲未滿1 00個/cm2般，於40 °C以上 1 5 0 °C以下之溫度下至少施以1 〇分鐘的熱處理施行至底版 ，或者施行至此光學補償薄膜貼合至偏光子後的複合偏光 板。於施行如此的熱處理下，則可提高複合偏光板的耐水 性，特別於高溫高濕條件中曝露時的耐性。 又，根據本發明之方法製造光學補償薄膜上，關於纖 維素系樹脂所構成之透明支撐體3上形成配向膜4，再於 其上形成液晶化合物之塗覆層5的光學補償薄膜2，對於 裁斷成2公分x5公分之長方形，並以液晶化合物的塗覆層 5作爲內側，以圓周爲5公分且高度爲2公分之圍成圓筒 的狀態（參照圖2 )於60 °C之溫水中浸漬60分鐘時，以 100個/cm2以上之密度發生氣泡的底版，以同一條件於溫 水中浸漬時發生氣泡的密度爲未滿1〇〇個/cm2般，於40 °C以上150°C以下之溫度下至少施以1〇分鐘的熱處理。施 以如此之熱處理，則可提高光學補償薄膜的耐水性。 此熱處理於60 °C以上，120 °C以下之溫度進行爲佳。 〔實施例〕 以下，示出實施例進一步具體說明本發明，但本發明 不被此些例所限定。 -18- 200819843 〔實施例1〕 由富士照相軟片（股）所取得“WV-S A”（商品名）爲 於三乙醯纖維素薄膜的單面形成聚乙烯醇系樹脂所構成的 配向膜，並於其上塗覆圓盤狀液晶所構成的光學補償薄膜 。若由此薄膜切出2公分χ5公分之長方形，並以其液晶塗 覆層作爲內側且以圖2所示形態之圍住狀態，並於6(TC之 溫水中浸漬60分鐘，則以約23 0個/cm2之密度發生氣泡 ，確認耐水性差。對於此底版，於1 2 0 °C施以3 0分鐘之熱 處理。熱處理後再以上述相同之方法評價耐水性時，確認 氣泡的發生數減少至8個/cm2，且耐水性提高。 另外，準備由碘染色聚乙烯醇延拉薄膜所構成的偏光 子。於此偏光子的單面，將施以上述熱處理之附有光學補 償機能的薄膜，以其三乙醯纖維素薄膜側透過接黏劑接黏 ，並於偏光子的另一面，將單面具有表面處理層之下列四 種三乙醯纖維素薄膜分別以三乙醯纖維素側（未設置表面 處理層之側）透過接黏劑接黏，作成複合偏光板。 (1 )單面設置防眩層的三乙醯纖維素薄膜（商品名 :“DTAC AG UV80 H-3”，大日本印刷（股）製）， (2 )單面設置防眩層之另外的三乙醯纖維素薄膜（ 商品名·· “DTAC AG5 UV80 H-13”，大日本印刷（股）製 )， (3 )單面以蒸鍍設置防止反射層的三乙醯纖維素薄 膜（商品名：“HT-ARPSMC”、凸版印刷（股）製）， (4 )單面設置清淨塗覆層的三乙醯纖維素薄膜（商 -19- 200819843 品名：“80CHC”，凸版印刷（股）製）。 更且，於構成此複合偏光板之光學補償薄膜的液晶塗 覆層側，設置丙烯酸系之感壓式接黏劑（Lintech (股）製 之“P2 3 6 JP”）層，製作附有感壓式接黏劑層之複合偏光板 。將此附有感壓式接黏劑層之複合偏光板，以吸收軸方向 相對於長邊以半時鐘回轉45 °之角度，以對角約8吋（ 2 0 0 m m )之尺寸切成小片後，貼合至1 . 1 m m厚之玻璃板， 並以溫度50°C，壓力5氣壓之條件進行20分鐘之加壓處 理後放置24小時。其次投入溫度65 °C、相對濕度90%的 筒溫：局濕烤爐，6 5小時後取出樣品觀察外觀時’使用設置 表面處理層之四種三乙醯纖維素薄膜的任一種均未發生剝 落和浮起等不良。 〔比較例1〕 將實施例1所用之相同附有光學補償機能的薄膜 “WV-SA”之底版就其原樣，未予以熱處理供使用，其他爲 同實施例1處理製作附有感壓式接黏劑層的複合偏光板， 並以同樣之方法進行高溫恆濕試驗。其結果，於光學補償 薄膜“WV-SA”之層間產生浮起，發生圖5所例示的鑽隧道 〔參考例〕 於實施例1中，令熱處理溫度與時間變化時之溫水浸 漬試驗後所觀察的氣泡數（個/cm2)整理於表1。 -20- 200819843 令熱處理溫度與時間變化時之溫水浸漬試驗後的氣泡數（ 個 /cm2) _ 時間\ 50°C 60°C 70°C 80°C 90°C 100°c 110°C 120°C 0分鐘 230 30分鐘 230 230 230 230 180 180 52 6 3.5小時 50 30 50 6 18小時 230 230 230 3 24小時 3 4 0 0 50小時 180 180 180 4 168小時 50 50 6 4 註）空欄位爲無數據 【圖式簡單說明】 圖1爲示出本發明之複合偏光板之構成例的剖面模式 圖。 圖2爲光學補償薄膜於溫水試驗時之長方形樣品的平 面圖（A )、和將此長方形樣品於溫水中浸漬而以圍住狀 態表不的斜視圖（B )。 圖3爲不出熱處理前之光學補償薄膜於溫水試驗時之 表面狀態的照片。 圖4爲示出以溫水試驗幾乎完全未察見氣泡之光學補 償薄膜之表面狀態的照片。 圖5爲將發生鑽隧道之偏光板表面端部予以攝影的參 考照片。 -21 - 200819843 【主要元件符號說明】 1 :偏光子 2 :光學補償薄膜 3 z透明支撐體 4 :配向膜 5 :液晶化合物之塗覆層 7 :透明保護薄膜 8 :表面處理層 9 :感壓式接黏劑層 1 〇 :光學補償薄膜捲起時的端部 1 2 :固定端部的接黏膠帶 20 :鑽隧道 -22-Vertical Alignment: Vertical alignment, IPS (In-plane Switching), etc., but in these modes, liquid crystal molecules are leaky due to phase difference 和, and squint in polarizing plate When the axis angles are not uniform, the narrow direction (azimuth angle) of the viewing angle of the weak point exists. As a method of amplifying the viewing angle of such a weak point, a method of optically compensating a liquid crystal element and a polarizing plate with a retardation film is widely used. Such a retardation film or an optical compensation film is used in accordance with the phase difference 液晶 of the liquid crystal in the liquid crystal element, the alignment direction, the driving mode of the liquid crystal molecules, and the like, and various types of substances are used. One of such retardation films or optical compensation films is one in which the liquid crystal compound coating exhibits optical characteristics on a transparent support. Usually, a liquid crystal compound is coated on a transparent support, but in many cases, an alignment film is formed in advance on the transparent support in order to align the liquid crystal compound in a specific direction. Japanese Laid-Open Patent Publication No. Hei 9- 1 7 9 1 2 5 (Patent Document 1) discloses that an alignment film is provided on a transparent support to form a support having an alignment film, and a disk shape is provided on the alignment film. An optically anisotropic layer (optical compensation layer) composed of a compound is formed into an optical compensation sheet. The material of the alignment film must be selected in consideration of alignment characteristics, coating properties, optical properties, durability, etc., and in particular, in terms of alignment characteristics and coating properties, materials which are relatively resistant to water, in other words, are selected. Selected from hydrophilic materials. For example, in the above Patent Document 1, it is recommended to use polyvinyl alcohol as an alignment film. In the case where the alignment film and the coating layer are composed of a material which is resistant to water, the durability in an environment containing a large amount of moisture is insufficient, for example, the liquid crystal display is uncomfortable under high temperature and high humidity conditions. Specifically, under the influence of water, when any layer loses sufficient adhesion, the external stress caused by the heat of the other layers constituting the polarizing plate and the expansion and contraction caused by moisture absorption and desorption occur between the layers. Peeling and destruction of the layer itself. As will be described in more detail, it is found that a hydrophilic alignment film is formed on a transparent support composed of a cellulose resin such as triacetonitrile cellulose, and an optical layer of a coating layer of a liquid crystal compound is formed thereon on -6-200819843. The compensation film is a polarizing plate which is adhered to one side of the polarizer and is adhered to the transparent protective film of the usual triacetyl cellulose on the multi-face of the polarizer, and is exposed to high temperature and high humidity conditions, and the hydrophilic alignment film is used. It is affected by moisture' and the adhesion between the alignment film and the layers at the end of the polarizing plate is lowered, so that floating at any interface of the transparent support/alignment film/liquid crystal compound coating layer is caused here. The starting point causes a tunnel-like void to proceed inside the polarizing plate. The following 'refers to this phenomenon as a drill tunnel. Fig. 5 is a photograph showing an enlarged surface end portion of a polarizing plate in which a tunnel is drilled. In the figure, it is understood that the right side is the end of the polarizing plate, and a large number of tunnels 20 are grown therefrom. [Problem to be Solved by the Invention] The object of the present invention is to form an alignment film on a transparent support composed of a cellulose resin. Further, an optical compensation film on which a coating layer of a liquid crystal compound is formed, or a composite polarizing plate having the transparent support side attached to a polarizer, even if the optical compensation film contains a layer having low resistance to water, It can prevent interlayer peeling and layer breakage under moist heat conditions, and improve its water resistance. As a result of the investigation, it has been found that such a material having low water resistance is subjected to heat treatment to improve water resistance, and a composite polarizing plate which does not have excellent durability as described above is obtained, and the present invention has been completed. (Means for Solving the Problem) -7- 200819843 That is, according to the present invention, an optical compensation film which is provided on a transparent support composed of a cellulose resin to form an alignment film, and a coating layer of a liquid crystal compound is formed thereon. a composite polarizing plate which is bonded to one side of a polarizer with its transparent support side, and the optical compensation film is cut into a rectangle of 2 cm X 5 cm, and the coating layer of the liquid crystal compound is used as the inner side. A composite polarizing plate having a bubble density of less than 100 cells/cm 2 which is formed when the circumference is 5 cm and the height is 2 cm in a state of being surrounded by a cylinder and immersed in warm water of 60 ° C for 60 minutes. In the composite polarizing plate described above, the optical compensation film is in the form of a cylinder having a rectangular shape of 2 cm x 5 cm and a coating layer of a liquid crystal compound as the inside, and having a circumference of 5 cm and a height of 2 cm. It is preferred to apply heat treatment at a bubble density of 60 pieces/cm2 or less when immersed in warm water of 60 ° C for 60 minutes. In the composite polarizing plate, the transparent protective film is bonded to the opposite side of the optical compensation film bonding surface of the polarizer, and both sides of the polarizer can be protected. In this case, the transparent protective film is preferably surface-treated with the opposite side of the polarizer. This transparent protective film is made of, for example, a cellulose-based resin such as triacetyl cellulose. On the other hand, the alignment film in the optical compensation film is usually composed of a hydrophilic resin, and is made of, for example, a polyvinyl alcohol-based resin. The coating layer of the liquid crystal compound constituting the optical compensation film may be an optical compensation layer containing a discotic liquid crystal. The optical compensation layer is a negative birefringent layer composed of a liquid crystal compound having a disc-shaped structural unit, and the disc surface of the disc-shaped structural unit is inclined to the surface of the transparent support, and the disc-shaped structural unit - 8 - 200819843 The angle formed by the disk surface and the transparent support surface is formed by changing the thickness direction of the optical compensation layer. At this time, the angle formed by the disc surface of the disc-shaped structural unit with respect to the surface of the transparent support body is increased in the thickness direction of the optical compensation layer as the distance from the transparent support side of the optical compensation layer increases. A pressure-sensitive adhesive layer is disposed on the outer side of the coating layer of the liquid crystal compound of the optical compensation film, and can be bonded to the liquid crystal element. Further, according to the present invention, it is also possible to provide the composite polarizing plate and the liquid crystal element according to any of the above, and to laminate the above-mentioned composite polarizing plate with the optical compensation film side through the pressure-sensitive adhesive layer on one surface of the liquid crystal element. Liquid crystal display device. Furthermore, according to the present invention, there is also provided a method for producing a composite polarizing plate which is improved in water resistance as described above, which comprises forming an alignment film on a transparent support composed of a cellulose resin, and then forming a liquid crystal compound thereon. When the optical compensation film of the coating layer is bonded to the polarizer on the side of the transparent support and the composite polarizing plate is manufactured, the optical compensation film is cut into a rectangle of 2 cm X 5 cm and coated with a liquid crystal compound. When the layer is immersed in a 60 ° C warm water for 60 minutes in a state of a circumference of 5 cm and a height of 2 cm in a cylinder, the bottom plate of the bubble is generated at a density of 100 / cm 2 or more, and the optical compensation is performed for this. The film is immersed in warm water under the same conditions, and the density of the bubbles is less than 100/cm2, and the heat treatment is performed at a temperature of 40 ° C or more and 150 ° C or less for at least 10 minutes, or is performed to the foregoing. The optical compensation film is bonded to the composite polarizing plate after the polarizer. -9 - 200819843 Further, according to the present invention, there is also provided a method for producing an optical compensation film which is improved in water resistance as described above, and a liquid crystal compound is formed on a transparent support formed of a cellulose resin. The optical compensation thin of the coating layer is cut into a rectangle of 2 cm χ 5 cm, and the liquid crystal layer is used as the inner side, and immersed in warm water of 60 ° C for 60 minutes in a state of a circumference of 5 cm and a height of 2 cm. The density of the gas is 1%, and the density of the bubbles in the warm water is less than 100/cm2 under the same conditions, and the heat treatment is performed at 4 (TC) at a temperature of J for at least 10 minutes. The temperature is preferably 60° C. or more and 120° C. or less. (Effect of the Invention) The composite polarizing plate of the present invention is optically compensated for containing a hydrophilic layer, for example, a hydrophilic alignment film containing a hydrophilic alignment film. The influence, for example, when the composite polarizing plate is dehumidified, the interlayer compensation of the optical compensation film can be prevented, and the accompanying drilling tunnel can be suppressed. Further, according to the method for producing a composite polarizing plate of the present invention, the method for producing a thin film can be surely produced as described above for improving the polarizing plate or the water resistance thereof has been used. The improved optical complementary composite polarizing plate is a method of closing the film, and then the film is formed when the coating of the composition is impregnated into a cylinder/cm 2 or more. In the method of lower than 150 ° C, the film at the hot portion Even if it is shaped, it can be placed under the high-temperature high-peeling and layer-breaking composite polarizing element, and can also be optically compensated for the water-based composite compensation film. -10- 200819843 [Embodiment] The following is also referred to the appropriate drawing side. A specific embodiment of the present invention will be described. A layer configuration example of the composite polarizing plate of the present invention is shown in a sectional view in Fig. 1. (A) of Fig. 1 shows a basic layer constitution, and the composite polarizing plate is a fiber. An alignment film 4 is formed on the transparent support 3 made of a plain resin, and the optical compensation film 2 on which the coating layer 5 of the liquid crystal compound is formed is attached to the side of the transparent support 3 to the polarizer 1 It is composed of one side. It is preferable to apply the transparent protective film 7 to the opposite side of the bonding surface of the optical compensation film 2 of the polarizer 1. Further, as shown in FIG. 1(B), the transparent protective film 7 is The outer side, that is, the opposite side to the polarizer 1, preferably has the surface treatment layer 8. (B) of Fig. 1 is the same as (A) of Fig. 1 except that the surface treatment layer 8 is provided outside the transparent protective film 7. Therefore, the same reference numerals are given to the same parts in (A), and the repeated description is omitted. On the outer side of the optical compensation film 2, that is, the surface of the coating layer 5 of the liquid crystal compound, a pressure-sensitive adhesive for bonding to the liquid crystal element is provided. The agent layer 9 is first described with reference to Fig. 1. The polarizer 1 is an optical element that transmits linearly polarized light having a vibration surface having a predetermined direction and absorbs linearly polarized light having a vibration surface in a direction perpendicular thereto. Specifically, a film of a polyvinyl alcohol-based resin film which adsorbs and aligns a dichroic dye can be mentioned. A dye-based polarizer which is an iodine-based polarizer which adsorbs iodine as a dichroic dye and a dichroic dye as a dichroic dye can be used. The transparent support 3 constituting the optical compensation film 2 is composed of cellulose resin -11 - 200819843. Specific examples of the cellulose-based resin include acetaminophen-based resins such as diethyl phthalocyanine and triethyl hydrazine cellulose. Among them, triethylene phthalocyanine is generally used. The alignment film 4 formed on the transparent support 3 is usually composed of a hydrophilic resin, and is generally made of a polyvinyl alcohol-based resin. The polyvinyl alcohol-based resin may be, for example, a modified polyvinyl alcohol obtained by introducing an alkyl group or the like. Usually, a coating layer composed of such a hydrophilic resin is formed on the transparent support 3, and the surface thereof is subjected to rubbing treatment to form an alignment film 4. The coating layer 5 of the liquid crystal compound is, for example, a nematic liquid crystal which is an oblique alignment ("NH Film" sold by Nippon Oil Co., Ltd.), but generally includes a coating containing discotic liquid crystal. The liquid is applied and the optical compensation layer is aligned. The optical compensation layer is a negative birefringent layer composed of a liquid crystalline compound having a disc-shaped structural unit, and the disc surface of the disc-shaped structural unit is inclined to the transparent support surface, and the disc-shaped structural unit The angle between the disc surface and the transparent support surface is preferably changed in the thickness direction of the optical compensation layer. In this form, the angle formed by the disc surface of the disc-shaped structural unit with respect to the transparent support surface increases in the thickness direction of the optical compensation layer as the distance from the transparent support side of the optical compensation layer increases. The mixed alignment is also effective. The angle formed by the disk surface of the disk-shaped structural unit with respect to the surface of the transparent support body is, for example, a structure in which the transparent support body side is sequentially increased in a range of about 5 to 50 degrees. Specific examples of the optical compensation film which forms the coating film of the alignment film and the disc-shaped crystal on the transparent support include "Wide Blue" Film (also expressed by "WVFilm") sold by Fuji Photo Film Co., Ltd. Wait. -12- 200819843 The transparent protective film 7 bonded to the other surface of the polarizer 1 can be any transparent resin film used in the past. For example, a film of polyolefin, polymethyl methacrylate, polycarbonate, polyethylene terephthalate, cyclic olefin resin (original borneol resin), and triacetyl cellulose can be used. A film of a cellulose resin represented by diacetyl cellulose or the like. Among them, a cellulose resin, particularly a film of triacetyl cellulose, is preferably used. The surface treatment layer 8 formed on the surface of the transparent protective film 7 is used as a display surface side (viewing side) when the polarizing plate is applied to a liquid crystal display device, and the layer provided by the physical properties is improved. Specifically, a hard coat layer for improving the scratch resistance of the surface, etc., an anti-glare layer for preventing external light reflection and flashing, and anti-reflection for preventing external light reflection may be cited. A layer for preventing a charging layer or the like provided by static electricity generation. The hard coat layer can be provided by a method of applying a UV-curable hard coat resin, and irradiating it with ultraviolet rays to harden it. The anti-glare layer is, for example, an ultraviolet curable resin to which an anti-drying agent has been added, and is irradiated with ultraviolet rays to harden it, and the ultraviolet curable resin is irradiated in a state of contacting the relief model according to the method in which the anti-tacking agent is uneven. Ultraviolet rays, and methods of hardening to cause irregularities can be set. The antireflection layer can be provided by a method of depositing one or more layers of a metal oxide or the like. Further, the antistatic layer can be provided by a method in which an ultraviolet curable resin which is prevented from being charged by a coating, and which is irradiated with ultraviolet rays to harden it. On the outer side of the optical compensation film 2, that is, the surface of the coating layer of the liquid crystal compound 5-13-200819843, a pressure-sensitive adhesive layer 9 for bonding to the liquid crystal element may be provided. The inductive adhesive layer 10 is made of an adhesive resin known in the form of a pressure-sensitive adhesive type, which is also known as a binder. As described above in the composite polarizing plate, as described in the prior art, when exposed to high temperature and high humidity conditions, the 'alignment film' is particularly hydrophilic, and the alignment film is affected by moisture, which makes the alignment film and the layers closely adhere. Since the force is lowered, the interface of any of the transparent support/alignment film/liquid crystal compound coating layer causes floating, and a tunnel-like void is formed inside the polarizing plate as a starting point, that is, the tunnel is caused to be drilled. According to the investigation by the inventors of the present invention, an alignment film composed of a polyvinyl alcohol-based resin is formed on a transparent support having a film of triacetyl cellulose, and a coating of discotic liquid crystal is formed thereon. In the layer, the disk surface of the disc-shaped liquid crystal is inclined with respect to the surface of the transparent support body, and the angle between the disc surface and the transparent support surface is in the thickness direction of the disc-shaped liquid crystal coating layer, with transparent support When the optical compensation film "WV-SA" manufactured by Fuji Photo Film Co., Ltd., which has a structure in which the distance on the body side is increased, is increased, the occurrence of the above-described drilling tunnel is remarkable. The occurrence of such a tunnel is considered to be due to the hydrophilicity of the polyvinyl alcohol-based resin of the alignment film, and the water resistance is insufficient. In order to quantitatively judge the water resistance of such a member having low water resistance, it has been found that the following method is effective. That is, the target film (optical compensation film) was cut into a rectangle of 2 cm x 5 cm as shown in plan view in Fig. 2(A). Next, the rectangular shape was rolled up inside the coating layer of the liquid crystal compound to form a cylinder having a circumference of 5 cm and a height of 2 cm. The state of this enclosing is shown in a perspective view in (B) of Fig. -14-200819843. To enclose (when the two ends of the width of 2 cm are joined) 1 (to be fixed. In this state, immerse in 6 〇 ° C of warm water at this time, in the sample with poor water resistance, the cause of bubbles is water Acetylcellulose/with [[] viscous force is reduced, so it floats between layers. The highly optically compensated film does not occur. In the above-mentioned warm water immersion test, a poor optical compensation film occurs. Thereafter, in the case of a conventional composite polarizing plate, the possibility of tunneling floating and peeling occurs at high temperature and high peeling> In order to improve the water resistance of the optical compensation film in the warm water immersion test, it is found that the heat treatment is performed. Therefore, in the present invention, the optical compensation film 2 of the coating layer 5 of the compound of the alignment film 4 is formed on the transparent support 3 which is formed, and the optical compensation film 2 is sufficiently heated to impart heat resistance to the film 2. In Fig. 3, a photograph of the surface of the optical compensation film impregnated with the above warm water at a magnification of about 10 lamps is shown. Further, in Fig. 4, a magnifying glass cover showing an optical compensation film which is almost completely free of bubbles occurs. A photograph of a transparent fluorescent observation, it was observed the state of the gas sample end portion engaged by the either side view), then to stick the tape 12 to stain for 60 minutes. Many bubbles. This type of 3 film/liquid crystal coating layer occurs if it is resistant to water. Many bubbles, and the water resistance step is applied to the polarizer, and under wet conditions, it is very awkward to pass through the interlayer. The phenomenon of multi-bubble, and the optical compensation film is applied to the cellulose-based resin, and liquid crystal is formed thereon, especially if the water resistance is insufficient, the magnifying glass cover which is many times of bubble times in the optical compensation test can be improved to be fluorescent. The surface of the test was immersed in warm water at a magnification of about 1 〇. The optical compensation film itself is packaged, and the sheets of Figures 3 and 4 are observed from the side of the transparent support. Thereafter, after immersing in warm water of 60 ° C for 60 minutes, and taking out from the warm water and observing the surface of the optical compensation film, an optical compensation film in which bubbles are generated at a density of 100 / cm 2 or more is used. In the case of bonding to a polarizer to form a composite polarizing plate, such a tunnel is difficult to occur if the tunnel is easily formed by the interlayer peeling of the optical compensation film under high temperature and high humidity conditions, and the density of the bubbles is lowered. Then, when bubbles are generated at a density of 1 〇〇/cm 2 or more in the warm water immersion test described above, it is judged that the water resistance is low, and only less than 100 /cm 2 in the same warm water immersion test. When the density of the bubble occurs, it is judged that the water resistance is high. The basis for high water resistance is preferably a density of 60 bubbles/cm 2 or less. The heat treatment for improving the water resistance of the optical compensation film is preferably carried out at a temperature of from 4 0 ° C to 150 ° C for more than 10 minutes. The heat treatment temperature at this time is preferably 60 ° C or more and 120 ° C or less. Further, it is more preferable that the heat treatment time is 30 minutes or longer. The upper limit of the heat treatment time is not particularly limited, and the time required to improve the productivity and water resistance is determined. If the temperature is raised, it is completed in a relatively short period of time. If the temperature is lowered, it must be relatively long. The reason why the water resistance is improved by the heat treatment is considered to be, for example, because the degree of crosslinking of the alignment film and the coating layer is increased, so that the water becomes insoluble, but the detailed reason has not been ascertained. The timing of this heat treatment is before bonding to the polarizer, that is, even if the optical compensation film itself is heat-treated, it may be heat-treated after the composite polarizing plate is formed. At least, the heat applied in the usual steps in forming the polarizing plate is not the object of heat treatment in the present invention. That is, in the present invention, the so-called "heat treatment" refers to the manufacture of polarized light with the so-called "optical compensation film (transparent protective film 0)) - bonding with a polarizer to form a pressure-sensitive adhesive layer". The usual steps of the sheet are different, mainly for the heat treatment step provided to increase the water resistance of the optical compensation film containing the coating layer of the liquid crystal compound. Therefore, this heat treatment is performed at least on one side of the optical compensation film, particularly in a state where the coating layer of the liquid crystal compound is exposed. As described above, in the present invention, an optical compensation for forming the alignment film 4 on the transparent support 3 made of the cellulose resin and forming the coating layer 5 of the liquid crystal compound thereon will be described with reference to FIG. The film 2 is a composite polarizing plate which is bonded to one side of the polarizer by the transparent support 3 side. The optical compensation film 2 is cut into a rectangle of 2 cm χ 5 cm, and is coated with the coating layer 5 of the liquid crystal compound. a bubble density of less than 1 //cm 2 when immersed in a warm water of 60 ° C for 60 minutes in a state surrounded by a cylinder having a circumference of 5 cm and a height of 2 cm (refer to FIG. 2 ). Heat treatment. The composite polarizing plate shown in Fig. 1 is bonded to a liquid crystal element group to form a liquid crystal display device, and is bonded to the liquid crystal element through the pressure-sensitive adhesive layer 9 on the side of the optical compensation film 2. Further, in the method of the present invention, a composite polarizing plate is produced, an alignment film 4 is formed on a transparent support 3 composed of a cellulose resin, and an optical compensation film 2 of a coating layer 5 of a liquid crystal compound is formed thereon. When the transparent support 3 side is bonded to the polarizer to produce a composite polarizing plate, the optical compensation film 2 is cut into a rectangle of 2 cm x 5 cm, and the coating layer 5 of the liquid crystal compound is used as the inner side, and the circumference is 5 cm and the height -17-200819843 is a state in which the cylinder is immersed for 60 minutes in a state of 2 cm in a cylinder (refer to FIG. 2), and a bubble bottom plate is formed at a density of 1 〇〇/cm 2 or more, and The density of the bubble generated when immersed in warm water under the same conditions is less than 100 pieces/cm2, and is applied for at least 1 minute at a temperature of 40 ° C or more and 150 ° C or less. The heat treatment is applied to the master plate, or the composite polarizing plate after the optical compensation film is attached to the polarizer. Under such heat treatment, the water resistance of the composite polarizing plate can be improved, particularly in the case of exposure in high temperature and high humidity conditions. Further, in the optical compensation film produced by the method of the present invention, the optical compensation film 2 on which the alignment film 4 is formed on the transparent support 3 composed of the cellulose resin and the coating layer 5 of the liquid crystal compound is formed thereon is Cut into a rectangle of 2 cm x 5 cm, and take the coating layer 5 of the liquid crystal compound as the inner side, and form a cylinder with a circumference of 5 cm and a height of 2 cm (refer to Fig. 2) in warm water of 60 °C. When immersed for 60 minutes, the bottom plate of the bubble is formed at a density of 100 pieces/cm 2 or more, and the density of bubbles generated when immersed in warm water under the same conditions is less than 1 //cm 2 and is less than 40 ° C to 150 ° C. Heat treatment at least 1 minute at a temperature. By such heat treatment, the water resistance of the optical compensation film can be improved. This heat treatment is preferably carried out at a temperature of 60 ° C or higher and 120 ° C or lower. [Examples] Hereinafter, the present invention will be specifically described by way of examples, but the present invention is not limited by the examples. -18-200819843 [Example 1] "WV-S A" (trade name) obtained from Fuji Photo Film Co., Ltd. is an alignment film composed of a polyvinyl alcohol-based resin formed on one side of a triacetyl cellulose film. And an optical compensation film composed of a discotic liquid crystal is coated thereon. If the film is cut into a rectangle of 2 cm χ 5 cm, and the liquid crystal coating layer is used as the inner side and enclosed in the form shown in Fig. 2, and immersed in 6 (TC warm water for 60 minutes, it is about 23 Bubbles were formed at a density of 0/cm2, and it was confirmed that the water resistance was poor. For this master, heat treatment was performed at 120 ° C for 30 minutes. After the heat treatment, the water resistance was evaluated by the same method as above, and the number of occurrences of bubbles was confirmed to decrease. Up to 8 pieces/cm2, and water resistance is improved. In addition, a polarizer composed of an iodine-dyed polyvinyl alcohol film is prepared. On one side of the polarizer, the optically compensated film with the above heat treatment is applied. The following three kinds of triacetyl cellulose films having a surface treatment layer on one side of the triacetyl cellulose film are adhered to the other side of the polarizer, and the other side of the polarizer is made of triacetyl cellulose. (The side of the surface treatment layer is not provided) is bonded to the adhesive to form a composite polarizing plate. (1) A triacetyl cellulose film having an antiglare layer on one side (trade name: "DTAC AG UV80 H-3", Large Japanese printing (share) system, (2) single side An additional antimony film of anti-glare layer (trade name: "DTAC AG5 UV80 H-13", manufactured by Dainippon Printing Co., Ltd.), (3) three anti-reflection layers are provided by vapor deposition on one side Acetyl cellulose film (trade name: "HT-ARPSMC", letterpress printing), (4) Triethylene cellulose film with a clear coating layer on one side (Shang -19- 200819843 Product Name: "80CHC Further, in the liquid crystal coating layer side of the optical compensation film constituting the composite polarizing plate, an acrylic pressure sensitive adhesive ("P2 3" manufactured by Lintech Co., Ltd.) is provided. 6 JP") layer, a composite polarizing plate with a pressure-sensitive adhesive layer is prepared. The composite polarizing plate with a pressure-sensitive adhesive layer is rotated halfway with respect to the long side in the absorption axis direction. The angle of ° is cut into small pieces at a diagonal of about 8 吋 (200 mm), and then bonded to a 1.1 mm thick glass plate and subjected to a temperature of 50 ° C and a pressure of 5 at 20 °C for 20 minutes. After the pressure treatment, it was left for 24 hours. Secondly, the temperature of the cylinder was 65 °C and the relative humidity was 90%: the wet oven, 6 When the sample was taken out after 5 hours, the appearance was observed, and no defects such as peeling and floating were observed in any of the three kinds of triacetylcellulose films provided with the surface treatment layer. [Comparative Example 1] The same as that used in Example 1 was attached. The bottom plate of the optical compensation function film "WV-SA" was used as it was without heat treatment, and the composite polarizing plate with the pressure-sensitive adhesive layer was processed in the same manner as in Example 1 and was carried out in the same manner. High temperature and humidity test. As a result, floating occurs between the layers of the optical compensation film "WV-SA", and the drill tunnel illustrated in Fig. 5 occurs. [Reference Example] In the first embodiment, the temperature of the heat treatment temperature and time are changed. The number of bubbles (number/cm 2 ) observed after the water immersion test was summarized in Table 1. -20- 200819843 Number of bubbles after warm water immersion test when heat treatment temperature and time change (times / cm 2 ) _ time \ 50 ° C 60 ° C 70 ° C 80 ° C 90 ° C 100 ° c 110 ° C 120 °C 0 minutes 230 30 minutes 230 230 230 230 180 180 52 6 3.5 hours 50 30 50 6 18 hours 230 230 230 3 24 hours 3 4 0 0 50 hours 180 180 180 4 168 hours 50 50 6 4 Note) The empty field is [Brief Description of the Drawings] Fig. 1 is a schematic cross-sectional view showing a configuration example of a composite polarizing plate of the present invention. Fig. 2 is a plan view (A) of a rectangular sample of the optical compensation film in the warm water test, and a perspective view (B) of the rectangular sample immersed in warm water to surround the state. Fig. 3 is a photograph showing the surface state of the optical compensation film before the heat treatment in the warm water test. Fig. 4 is a photograph showing the surface state of the optical compensation film in which the bubble is almost completely absent in the warm water test. Fig. 5 is a reference photograph for photographing the end surface of the polarizing plate on which the tunnel is drilled. -21 - 200819843 [Explanation of main component symbols] 1 : Polarizer 2 : Optical compensation film 3 z Transparent support 4 : Alignment film 5 : Coating layer of liquid crystal compound 7 : Transparent protective film 8 : Surface treatment layer 9 : Pressure sensitive Adhesive layer 1 〇: End portion of optical compensation film when rolled up 1 2: Adhesive tape 20 at fixed end: Drill tunnel-22-