200912400 六、發明說明： 【發明所屬之技術領域】 本發明係關於一種減少因貼著在跨距長度19吋以上 之TN模式大型顯示裝置的偏光薄膜的收縮而在顯示裝置 之緣部發生漏光的方法及顯示裝置。 【先前技術】 顯示裝置、特別是液晶顯示裝置，係一種在形成液晶 胞（Cell)之二塊玻璃基板之表面，將偏光板配置在正交偏 光（cross nicols ;又稱「正交尼科耳」）位，並將電壓施 加在填充於液晶胞中之液晶成分，變更液晶成分之配向狀 態，以控制來自配置於液晶顯示裝置之背面侧的光源之光 的穿透性，藉此使電氣信號顯現化之裝置。 在這種顯示裝置、特別是在液晶裝置，如上所述貼著 有偏光薄膜，由於在該顯示裝置中，一般係具備貼著有在 表背面配置無延伸之保護薄膜（TAC)的延伸薄膜（PVA)之構 成，因而具有以下特性：經延伸加工之偏光薄膜言因貼合 時之熱、或使液晶裝置長時間驅動時所產生的熱而發生熱收 縮，而在被貼著之偏光薄膜的緣部會產生高的内部應力。 另一方面，貼著該偏光薄膜之黏著劑沒有經延伸加 工，因此即使將熱施加在黏著劑亦不會發生熱收縮。 當熱施加在該液晶裝置時，液晶裝置之玻璃基板雖無 特別變動，但經延伸加工之偏光薄膜會朝液晶裝置表面之 中心方向發生熱收縮，而如第2圖（B)箭頭所示般於内部存 在朝中心方向之大的内部應力。 4 320244 200912400 此時貼著在液晶裝置之玻璃基板表面的黏著劑雖係呈 貼著在未因熱而變動之玻璃基板表面的狀態，但貼著在偏 光薄膜表面的黏著劑會因偏光薄膜之熱收縮而被引拉。而 且，因該熱收縮而被朝中心方向引拉之偏光薄膜内產生之 内部應力，偏光薄膜之功能會喪失或減低，即使在全面顯 示黑色時’該部分亦會從液晶裝置之緣部形成圓孤狀之白 色部。因有關該偏光薄膜之熱收縮而使光以圓弧狀穿透之 現象稱為漏光，形成該圓弧狀之光穿透率高的部分稱為漏 光部。 _ 當液晶裝置之尺寸（跨距長度）小時，偏光薄膜之熱收 縮亦小，在各個緣部所產生的漏光圓弧亦小，該漏光圓弧 會因配置在液晶襄置之顯示部周圍之用來支持液晶顯示部 的支持框而難以辨識其存在。 然而，最近之液晶顯示裝置大多使用跨距長度超過19 忖之大型液晶顯示裝置，而難以藉由支持框來覆蓋隱藏漏 光圓弧。此外，在大型液晶顯示裝置中，所貼著之偏光薄 膜的面積亦變得非常大’發生在液晶顯示裝置緣部的漏光 圓弧之大小亦逐漸變大，而必須研擬對於該漏光之根本對 策。 液晶顯示震置之跨距長度未達19啊，為了防止因偏 光薄膜之熱收縮所造成的漏光’而使用包含比車交多量低分 子量體的黏著劑或凝膠率較低之黏著劑等可追隨偏=薄: 之熱收細之應力緩和性局的黏著劑。在未達19对大】的、广 晶顯示裝置中，由於偏光薄膜之收縮比較小，即使利= 320244 5 200912400 -述應力緩和性高的黏著劑，亦因漏光小而沒有實用上之問 題0 - 然而’在™模式液晶顯示裝置中，已有多數直徑超過 • 寸之大型液晶顯示裝置在市面上販售，目前在別模式 中亦存在有32吋之液晶顯示裝置。 斜找大型液晶顯示裝置中，當然所貼著之偏光薄膜亦 情液晶顯不裳置之大小而具有廣大面積。如前所述貼著 於液晶顯示裝置之偏光薄膜係經延伸，且該大面積 欠縮時所產生的内部應力變得非常大，採用在 奴液晶顯示裝置所❹之應力緩BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of reducing light leakage at the edge of a display device by shrinking a polarizing film attached to a TN mode large display device having a span length of 19 Å or more. Method and display device. [Prior Art] A display device, particularly a liquid crystal display device, is a surface of two glass substrates on which a liquid crystal cell is formed, and a polarizing plate is disposed in a cross-polarization (also referred to as "cross nicols" a voltage is applied to the liquid crystal component filled in the liquid crystal cell, and the alignment state of the liquid crystal component is changed to control the transmittance of light from the light source disposed on the back side of the liquid crystal display device, thereby making an electrical signal. Device for visualization. In such a display device, particularly a liquid crystal device, a polarizing film is attached as described above, and in the display device, a stretching film having a protective film (TAC) having no extension on the front and back surfaces is generally attached ( The composition of PVA) has the following characteristics: the polarizing film which is subjected to the stretching process is thermally contracted by the heat at the time of bonding or the heat generated when the liquid crystal device is driven for a long time, and is attached to the polarizing film. The edge produces high internal stresses. On the other hand, since the adhesive adhering to the polarizing film is not subjected to elongation processing, heat shrinkage does not occur even if heat is applied to the adhesive. When heat is applied to the liquid crystal device, the glass substrate of the liquid crystal device does not particularly change, but the stretched polarized film is thermally shrunk toward the center of the surface of the liquid crystal device, as shown by the arrow in FIG. 2(B). There is an internal internal stress that is large toward the center. 4 320244 200912400 At this time, the adhesive adhering to the surface of the glass substrate of the liquid crystal device adheres to the surface of the glass substrate which is not changed by heat, but the adhesive adhering to the surface of the polarizing film is affected by the polarizing film. Heat contracted and pulled. Moreover, the internal stress generated in the polarizing film which is drawn in the center direction due to the heat shrinkage, the function of the polarizing film is lost or reduced, and even when the black color is fully displayed, the portion will form a circle from the edge of the liquid crystal device. The white part of the solitude. The phenomenon in which light is transmitted in an arc shape due to thermal contraction of the polarizing film is referred to as light leakage, and a portion in which the arc-shaped light transmittance is high is referred to as a light leakage portion. _ When the size of the liquid crystal device (span length) is small, the thermal shrinkage of the polarizing film is also small, and the arc of light leakage generated at each edge is also small, and the light leakage arc is disposed around the display portion of the liquid crystal display. It is used to support the support frame of the liquid crystal display unit and it is difficult to recognize its existence. However, most recent liquid crystal display devices use a large liquid crystal display device having a span length of more than 19 Å, and it is difficult to cover a hidden light leakage arc by a support frame. In addition, in a large liquid crystal display device, the area of the polarizing film to be attached is also extremely large. The size of the light leakage arc occurring at the edge of the liquid crystal display device is gradually increased, and it is necessary to study the fundamentals of the light leakage. Countermeasures. The length of the span of the liquid crystal display is less than 19, and in order to prevent light leakage caused by thermal contraction of the polarizing film, an adhesive containing a small amount of a low molecular weight body or an adhesive having a low gel fraction can be used. Follow the bias = thin: the heat of the thinness of the stress relaxation of the adhesive. In the wide-angle display device of less than 19 pairs of large-sized display devices, since the shrinkage of the polarizing film is relatively small, even if the adhesive having high stress relaxation property is described, the light leakage is small and there is no practical problem. - However, in the TM mode liquid crystal display device, a large number of large-sized liquid crystal display devices having a diameter exceeding one inch have been commercially available, and currently 32-inch liquid crystal display devices exist in other modes. In the oblique looking large liquid crystal display device, of course, the polarizing film attached is also large in size and has a large area. As described above, the polarizing film attached to the liquid crystal display device is extended, and the internal stress generated when the large area is reduced is extremely large, and the stress applied to the liquid crystal display device is used.
:在各緣部所產生的圓弧狀漏光部的最大寬度有變I 的傾向。 門2〇t67:f 顯示裝置中的漏光’在曰本特 開2006一259664號公報（專利文獻υ中揭示有「一種且有 黏著劑層之偏光板，苴特擻為.紡動―w 種八有 的筚斟# & π ，、寻伐為.該黏者劑層之光彈性係數 ==:12(1/Pa)以上」。而且，在該專利文獻〗 本與(?基)丙稀酸苯醋共聚合而成。 無法完全防Μ光。 在糾文獻1之黏著劑，亦 (專利文獻1)日本特開2__259664號公 f發明内容】 (發明所欲解決之課題） 本發明之目的在於提供一種減少在跨距長度i9付以 320244 6 200912400 • 上之TN模式液晶顯示裝置之各緣部產生圓弧狀漏光部的 發生’而且縱然形成如上所述之漏光部，該漏光部之存在 - 亦難以辨識的方法。 、 再者’本發明之目的在於提供一種利用下述方法之顯 示裝置’該方法係減少在跨距長度19吋以上之ΤΝ模式液 晶顯示裝置之各緣部產生圓弧狀漏光部的發生，而且縱然 形成如上所述之漏光部，該漏光部之存在亦難以辨識。 (解決課題之手段） ,1' . ' 本發明係一種減少在該大型顧示裝置之緣部形成圓弧 狀之漏光的方法’其中，係減少因貼著在跨距長度19吋以 上之ΤΝ模式液晶顯示裝置之延伸偏光薄膜的熱收縮而在 該大型顯示裝置之緣部形成圓弧狀之漏光的方法， 係以對貼著該延伸偏光板薄膜的黏著劑賦予可抵抗該 延伸偏光板薄膜之熱收縮的強度，俾使產生在該大型顯示 裝置之各緣的漏光圓弧距離各緣的最大値（w )相對於大型 (顯示裝置之長邊的長度（L)的比（W/L)成為〇·〗以下，並且 將侧鏈導入該黏著劑之碳化氫主鍵，俾使在該大型顯示裝 置之緣部所形成之圓弧狀之漏光部分在變暗時之亮度（χ) 成為4cd/m2以下，且與未產生漏光之部分在變暗時度 (Y)的比率（χ/γ)為2〇以下。 本發明係一種顯示裝置，係利用了用以減少因貼著在 跨距長度19吋以上之TN模式液晶顯示裝置之延伸偏光薄 膜的熱收縮而在該大型顯示裂置之緣部形成圓弧狀漏光之 方法，以減少在該大型顯示裝置之緣部形成圓弧狀之漏 320244 7 200912400 者，其中’該方法係對貼著該延伸偏光板薄膜的黏著劑職 予可抵抗該延伸偏光板薄膜之純㈣強度，俾使產生在 該大型顯示裝置之各緣的漏光圓弧距離各緣的最大値⑺ 相對於大型顯示裝置之長邊的長度（L)的比（肌）成為〇」 以下，並J將側鍵導人該黏著劑之碳氫化合物主鏈，俾使 在該大型顯示裝置之緣獅成圓弧狀之漏光料在變暗時 ^度⑴成為㈣/仏下’且與未產生μ之部分在變暗 柃之亮度（Υ)的比率（χ/γ)為2〇以下。 在本發明中，縱然將偏光薄膜貼著在大型之液晶顯示 裝置，只要使用強度較高之堅牢的黏著劑，就能使因延伸 之偏先薄膜的收縮而在各緣部形成的漏光部變小。該黏著 劑之黏著強度大多來自形成勒签十 风黏者劑之鏈狀分子彼此束縛之 交聯構造，在本發财錢用㈣能基之交聯劑，以其中 =二個以上之官能基使具有鏈_造之黏㈣分子彼此束 缚’以對黏著劑本身賦予堅牢性。 即使如上所述使用堅牢之六胳 聯劑’仍會在形成液晶裝 置之玻璃基板的各緣部形成圓弧狀之漏光部。然而，根據 本發明，可使圓弧狀漏光部之最大寬度減於玻璃基板之 長邊長度（L)成為如上所述之非常狹&狀= 如此即使以堅牢之㈣劑貼著^^膜，在大型晝面 之液晶顯示裝置中，亦會如上所述沿著各緣部形成圓弧狀 之漏光部，但如此形成之圓弧狀漏光部在變暗時的亮度⑴ 為4cd/m m與正常貼著偏光薄膜之部分在變暗時的 亮度⑺之比㈣〇〇/〇〇)時，若其亮度比小，則漏光部 320244 8 200912400 -實質上難以被辨識為漏光部。 ^ 該漏光部難以被辨識為漏光部? p ’漏光部雖會形成，但 .在本發明中，藉由使用凝 .之内部應力儘可能針在端Λ间之』者劑使偏光薄膜 常小’且對黏著劑聚合物的側鏈之面積成為非 之亮度，儘管現實上==能基’藉此降低漏光部分 識為漏光部。、 ㈣光部，該漏光部亦難以被辨 (發明之效果） ”根據本發明，在跨距長度Μ相上之 日日顯示裝置中， 欲 杈式大型液 光邱八_f 吏&生在顯示裝置之各緣部的圓弧肤、 m t分變小，蚊該漏光部分不會顯眼。划弧狀漏 【貫施方式】 接著，具體㈣本發明之減 頻 $成圓弧狀漏光的方法及顯示裝置。 裝置之緣部 树明之漏光之減少方 置之跨距長度（s)為19分、， 在第1圖中顯示裝 本發明之漏光之減小*、、'上之大型TN模式顯示震置。在 其有用性越高，作：曰〉二液晶裝置之跨距長度⑻越長 限倍係相當於_二頓不裝置本身有其驅動限度，其上 該液晶液晶顯示裝置之前面， 該多數個液晶胞之貝的多數個液晶胞，在 玻續基板15。：，隔考配向膜、ίΤ〇電極等配置有 320244 9 200912400 _ 在該玻璃基板15之表面，藉由黏著劑層η貼著有偏 光薄膜19。偏光薄膜19係由經延伸之合成樹脂薄膜所形 成，在該偏光薄膜之表背面，通常配置有無延伸之保護薄 •膜⑽）。具有該構成之偏光薄膜19通常係在構成液晶裝 置之表背面的玻璃基板15配置有2片，使形成45。與135。 之正交偏光位。 該偏光薄膜19係藉由黏著劑層17貼著固定在玻璃芙 板 15 〇 土 該偏光薄膜19係如上所述為延伸薄膜，因此對該偏光 薄膜19施加熱時，如第2圖所示會朝液晶顯示裝置1〇之 中心方向產生熱收縮，但因TAC薄膜係無延伸薄膜，因此 不會產生熱收縮而產生内部應力。 特別是在熱收縮之方向（施加内部應力之方向）與偏光 軸之方向不同的部分（顯示裝置之各邊之中心部分），直線. 偏光會因雙折射而成為楕圓偏光，使光穿透，但在角部偏 光轴與收縮方向相似，因此不容易產生雙折射而不易漏 光，因而在顯示裝置之各邊會產生圓弧狀之漏光部。 在該TAC薄膜内存在強的内部應力之圓弧狀部分， 偏光薄膜之功能會受損，且會產生圓弧狀之漏光。在第2 圖（B)中，偏光功能因内部應力而受損之部分以符號丨％表 示，熱收縮之方向及強度以箭頭表示。 如第2圖（B)所示，該漏光係因經延伸之偏光薄膜19 叉到熱之影響而進行熱收縮所產生之内部應力高的部分。 在内部存在大的應力之圓弧狀部分，偏光薄膜之特性 320244 10 200912400 -^該應力而變化，在該部分中，偏光薄膜不會發揮偏光 薄膜之作用’且應由偏光薄膜1 g遮蔽之光會穿透液晶顯示 裝置。 ’ 在本發明之減少顯示裝置之漏光的方法中，首先為了 減少漏光面積，而使用堅牢之黏著劑使形成為圓弧狀之漏 光部20集中在端部（角部）。關於該圓弧狀之漏光部2〇的 大小，在液晶顯示裝置之長邊（L )之中央部，距緣部21之 距離（W)係最大。 本發明中，係使用堅牢之黏著劑將偏光薄膜貼著在玻 璃基板，俾使漏光圓弧之離各邊的最大値（w)相對於液晶 顯不裝置之長邊（L)的比率（W/L)通常成為〇1以下，更 么1為0 · 0 6以下。 在此使用之黏著劑係由具有乙烯性雙鍵之單體（共）聚 合而成之以碳氫鏈為主鏈之聚合體，其中，將具有來自丙 烯基之雙鍵的單體予以（共）聚合所得之聚合體的透明性 佳。： 在作為該黏著劑之主成分的（共）聚合體的主鏈中係例 如導入有：含有羥基、綾基（其鹽）、氨基、烷胺基、烷氧 f、醯胺基等極性基之側鏈；以及例如含有具有直鏈狀或 刀岐之烷基、可具有取代基之環烷基等飽和環狀碳氫化合 物基了具有取代基之笨基等來自環狀化合物之基、苯甲 基等來自環狀化合物之基等非極性基之側鏈。 具有該等側鏈之作為黏著劑之主成分的（共）聚合體， 通常具有100萬至250萬、較佳為12〇萬至200萬之重量 11 320244 200912400 平均分子量。再者，該（共）聚合體之分子量分佈越狹窄， 黏著劑層之構造越容易變得堅牢，亦不易產生黏著劑層之 黏著力的參差不齊。而且，作為該黏著劑之主成分的（共） 聚合體之分子量分佈（Mn/Mw)通常在2至20之範圍 内、較佳為4至10之範圍内，藉由使用該分子量分佈的黏 著劑之主成分（共）聚合體，容易形成堅牢之黏著劑層構造。 再者，作為該黏著劑之主成分的（共）聚合體，通常在 貼著偏光薄膜之環境下，必須保持良好之黏著性，該（共） 聚合體之玻璃轉移溫度（Tg)通常在-70至-10°C之範圍、 較佳為-50至-30°C之範圍。該（共）聚合體之玻璃轉移溫度 (Tg)，可於製造（共）聚合體後由所製造之（共）聚合體進行 實測，亦可利用Fox之式從用於（共）聚合之單體導出。 植設在該（共）聚合體之主鏈的極性側鏈或非極性側 鏈，可與構成黏著劑之（共'）聚合體的複氫主鏈直接結合， 亦可經由-0-C0-基、-C0-0-基等類似酯鍵之二價基、或 、-S-等類似鍵鍵之二價基、來自-0-P〇2-0-、-〇S〇2-〇-之磷酸或磺酸的基來進行結合。 具有該側鏈之（共）聚合體，可使具有乙烯性雙键之化 合物（共）聚合後，將所希望之基導入主鏈，亦可藉由使預 先導入所希望之基的具乙烯性雙鍵之單體（共）聚合來製 造。此外，亦可將所希望之基植設在如上述所製造之（共） 聚合體而製造具有所希望之基的（共）聚合體。 如上所述植接於形成黏著劑之黏著劑主成分的（共）聚 合體之羥基、羧基等極性側鏈，不但有助於玻瑜基板與偏 12 320244 200912400 薄膜，接著，而且在將交聯齊"為 成分的(共)聚合體時，成為與該交聯劑反應的活性” -黏著劑主成分的（共）聚合體間形成交 · ，劑主成分的⑷聚合體複合形成堅牢之三二欠 ^者 有該極性基之反覆單位，在 —— 體。具 (共）聚合體之單體⑽重量造作為黏著劑主成分的 %、較佳為含有…以二了含有°.5至10重量 里之範圍内的量。 與上述極性基反應而形成交聯構造之交聯劑，係 乙、=極性基反應之複數個基的化合物，可進行這ς》 應之基的例子，可列舉淨g §種反 吁衣氧基、異氰酸酯基、全屬數 等。在本發明中所使用之六心青曰泰金屬螯合基 讀個基，但在本發明中較佳為使用在該交聯劑4= 具備有助於交聯反應之4個以上之極性基的交聯劑。子内 _是在本發财，作為交制之化合物所具 助於父聯反應活性之極性基係環氧基，且難為使用在一 I分子内含有4個以上環氧基之化合物來作為交聯劑。該六 聯劑所具有之環氧基雖與例如植接在黏著劑之主鍵的S 或羧基產生反應，以形成分子間交聯構造並形成堅牢之黏 著劑構造，但導入於交聯劑之有助於交聯構造的基全部結 合的情況極少。在本發明中，使用含有4個以上之環氧基 的交聯劑，係考慮該環氧基之反應效率，即便使用例如^ 有4個環氧基之交聯劑，該環氧基之反應率通常最多也只' 有69%至77%左右，所導入之環氧基不會全部產生反應。 使用具有4個環氧基之交聯劑時，4個環氧基中平均三個 320244 13 200912400 -環氧基會與植接在黏著劑之主鏈的極性基相結合。由該結 合點來決定一平面。在由該三點所結合之黏著劑中，假設 有由結合之二點所決定之硬質的多數面，黏著劑之主鏈的 自由運動便明顯地受到限制而形成堅牢之黏著劑層。而 且’為了獲得可抵抗本發明之延伸偏光薄膜之熱收縮的強 度，較佳為使用相對於黏著劑聚合體1〇〇重量份為〇· 〇5至 0. 20重1份之形成如上所述交聯密度高之堅牢之黏著劑層 的交聯劑，並將凝膠分率設為85至95%。 再者’作為调配於黏著劑.層之交聯劑，雖有使用二官 月匕之|^異氰酸酯（P〇lyjs〇Cyanate)化合物之例’但使用該 一 g能之聚異氰酸酯時，2個異氰酸酯基雖比較容易反應， 4寒丨餘之1個異氰酸1旨基的反應性會變低，結果三官能之 ^異氰酸酯的反應率通常不會達到65%。因此，使用三官 能之聚異氰酸酯時，僅會以三官能之聚異氰酸酯化合物中 之2個異氰酸酯基來連結用以形成黏著劑之（共）聚合體的 2個主鏈，且無法抑制黏著劑層中之具有黏著性的（共）聚 k.. 合體在黏著劑層内的移動，黏著劑層會變為軟質且隨著偏 光薄膜之熱收縮而容易被拉近至液晶之中心部分，因此如 第2圖所示漏光部之大小、即W/L之値會變大。 在本發明之減少漏光之方法中，亦使用經延伸加工之 偏光薄膜，因此即便將黏著劑層作成相當地堅牢，亦無法 阻止圓弧狀之漏光部20因偏光薄膜之熱收縮而形成在顯 示裝置之緣部。然而，藉由依據本發明形成堅牢之黏著劑 層’漏光部20之最大寬度W相對於顯示裝置之長度L的比 14 320244 200912400 ， （W/L)為0. 1以下，較佳為0. 06以下，且與使用例如三官 能之聚異氰酸酯化合物時相比較，該漏光部20之面積本身 _ 會變得更小。 • 再者，在本發明之減少漏光之方法中，係在構成黏著 劑之（共）聚合體之主鏈中，植接具有芳香族環之基。可知， 由於將具有該芳香族環之基導入構成黏著劑之主鏈，故藉 由偏光薄膜19因熱收縮被拉長所施加之應力，使構成黏著 劑之成分的環狀構造的侧鏈配向，而減低漏光部20之光的 穿透率。 再者，將芳香族環導入側鏈的單體，因感温性高且高 溫時降低黏著聚合體之彈性率，因此可緩和因偏光板之熱 收縮所產生的應力。如此，為了在高溫時降低黏著劑之彈 性率並且在常溫或在通常使用溫度範圍下使之成為硬質且 凝聚力高之黏著劑，將芳香族環導入侧鏈的單體之同元聚 合物的玻璃轉移溫度較佳為-25°C至10°C，此外，具有芳 香族環之側鏈若在除了主鏈以外之黏著劑聚合體100重量 V %中通常為20至60重量％、較佳為30至40重量％之範 圍内的話，則可更加使漏光不明顯。 再者，可認為，在如此定向之黏著劑層中，四官能之 交聯劑中之約一個官能基並未反應而殘留，黏著劑層因偏 光薄膜19之熱收縮而被拉長時，殘餘之官能基的一部分會 與植接在形成黏著劑層之黏著性樹脂的官能基中未反應的 官能基之一部分結合，使施加有應力之黏著劑層17(a)更 剛硬，且在施加有該應力之黏著劑層17(a)中固定具有被 15 320244 200912400 ，設成固定方向之芳香族環的基。 因此，在第2圖（A)中，決定漏光部20中之任意點（X) 及配置有偏光薄膜19之部分的任意點（Y)，使該顯示裝置 .轉暗時漏光部分轉暗時的亮度（X)、與未產生漏光之部分轉 暗時的亮度（Y)之比率（X/Y)為20以下，較佳為10以下。 這是由於存在於施加有應力之黏著劑層17(a)之具有芳香 族環的基會緩和因偏光薄膜之熱收縮所產生的應力，而且 緩緩地進行配向而遮蔽所穿透之光的至少一部分，故亮度 X與亮度Y之差變得極小，且難以目視辨識因偏光薄膜之 熱收縮所產生之漏光部的存在。 如上述之本發明之減少漏光的方法，係形成堅牢之黏 著劑層使漏光部之面積縮小，並且使轉暗時之漏光部的亮 度與配置有偏光薄膜之部分的亮度之差縮小，藉此在構造 上即使藉由因偏光薄膜19之熱收縮所產生的應力而形成 漏光部，亦可使該漏光部之面積明顯地減小，且由於轉暗 時之漏光部的亮度與貼著有偏光薄膜之部分的亮度之差極 -- , ' 小，因此可發揮實質上幾乎無法辨識圓弧狀之漏光部的特 異效果。 (實施例） 接著，針對本發明之減少漏光的方法，例示實施例加 以說明，但本發明之方法並非由該實施例所限定者。 再者，本發明之膠質滲透層析法（GPC，Gel Permeation Chromatography)之測定條件係如下所述。 裝置 16 320244 200912400 東曹（股）公司製、HLC-8120 管柱 G7000HXL xl 支 GMHXL x2 支 G2500HXL xl 支 樣本濃度：1.5mg/ml(以四氫吱喃稀釋） 移動相溶劑：THF 流速：1. 0ml/mi η 溫度：40°C (實施例1) 依據通常方法，藉由以醋酸乙酯為反應溶劑之溶液聚 合，來製造由膠質滲透層析法測定之重量平均分子量為140 萬的共聚合體（A)。該共聚合體（A)之分子量分佈（Mn/Mw) 為5 〇 在該共聚合體（A)之由碳化氫所構成之主鏈，經由 -C0-0-結合有具有-CH2CH2CH2CH3之單體67. 5重量％、及具 有-CH2-CH2-OH之單體2重量％，且以具有-C00H基之單體 0. 5重量％及經由-C0-0-而具有-CH2-C6H5之單體30重量％ 之量進行共聚合。 針對該共聚合體（A)測定之玻璃轉移溫度（Tg)為-34 V。 將所得之共聚合體（A)在醋酸乙酯溶劑中的濃度調整 為15重量％後，在該溶液之固形份10 0重量份添加環氧系 四官能交聯劑（化合物名：N,N，N，N-四縮水甘油-m-二曱苯 17 320244 200912400 二胺、商品名：TETRAD0 X，三菱氣體化學（股）製）〇. 1重 量份，並均句混合以調製黏著劑塗布液。 將所得之黏著劑塗布液塗布在易剝離性PET薄膜，使 乾燥厚度成為25/zm，在去除溶液後，轉印在偏光薄膜並 且在23°C下熟成7天，以製造附有黏著劑層之偏光薄膜。 準備390mmx315mmxl.lmm之玻璃基板’ 一邊將易剝離 性PET予以剝離，一邊將如上述方式調製之附有黏著劑層之 偏光薄膜貼附在玻璃基板之兩面，使成為正交偏光位（45。、 ) ’並且在溫度、線壓5Kg/cm之條件下熱壓接於 玻螭基板後’在室溫下放置1小時。 θ與顯示器螢幕BENQ PF91G之偏光板更換，而安裝所 才于之偏光板。將顯示器螢幕連接在個人電腦，並設為全晝 =黑色顯示’利用亮度計RISA-C0L0R-PF91G(Highland公 司（有）製）來測定暗室下顯示器螢幕之亮度時，在玻璃基板 之緣°卩並未形成有圓弧狀之漏光部。 劑層攸如ΐ方式製造之附有偏光薄膜的玻璃基板刮取黏著 ’則得該黏著劑層之凝膠分率為91%。 論來看Y由於環氧基之反應率為69至77%，因此從機率 4個之中可形成存在於交聯劑内之交聯構造的活性環氧基 形成強靭 個與位於共聚合體（A)之側鏈的官能基結合並 進行反應之勘著劑層，但4個環氧基中約1個環氧基並未 接著 乂壤氧基之狀態殘存於交聯劑中。 72小時，【、將_不器螢幕在60°C、濕度95%之環境下放置 X進行偏光薄膜之熱變形的促進實驗。然後，在 320244 200912400 室溫放置1小時後，在暗室連接在個人電腦並設為全晝面 黑色顯示。利用亮度計RISA-C0L0R-CD8(Highland公司（有） 製）來測定全晝面黑色顯示之顯示器螢幕之亮度時，如第2 圖所示在玻璃基板之各緣部形成有圓弧狀之漏光部。將以 目視可辨識漏光之亮度（至2cd/m2為止）設為漏光部時，寬 度最寬廣之漏光部的寬度（W)相對於玻璃基板之長邊 (L)380mm 為 20.5mm。 因此，該玻璃基板之W/L値為0. 054，與一般液晶基 板之圓弧狀的漏光部相比較，得知該W/L之値非常小。 測定產生漏光之部分的亮度（X)，並且測定未發生漏光 部分轉暗時之亮度（Y)時，漏光部之最明亮之部分為 4cd/m2，稍明亮之部分為2cd/m2，未產生漏光之部分之亮 度（X)為0.2cd/m2,因此（X/Y)之値係在20至10之範圍内。 最明亮之部分幾乎由顯示裝置之框體所覆蓋，因此該顯示 裝置之實質的（X/Y)之値為10。該値越接近1表示越難以 看出漏光部之存在，(X/Y)之値10表示與習知之顯示裝置 比較漏光特別少。 儘管如上所述形成有漏光部，但轉暗時漏光部的亮度 係降低之原因在於，由於藉由形成堅牢之接著劑層，儘可 能使内部應力集中在端部，並且如上所述在恒溫槽加熱而 在偏光薄膜產生熱收縮時，第2圖（B)中以符號17a所示部 分的黏著劑，會伴隨偏光薄膜之熱收縮朝液晶顯示裝置之 中心方向被引拉，同時-CH2-C6H5會經由-C0-0-配向在構成 黏著劑之共聚合體（A)中，在此狀態下，殘存在交聯劑中之 19 320244 200912400 、衣氧基的至部分會產生反應，與殘存在共聚合體⑷ 之極性基形成新的交聯構造，且在用以黏著以符號1如所 ，示部分的黏著劑中使經配向na固定。 • 由於該經配向2_CIl2-C6H5顯示配向性，欲穿透該漏光 部之光的一部分由該黏著劑固定之—CH2_C6h5基阻止光之穿 透，因此根據本發明之方法，漏光部之亮度會變低。 為了比較上述點，以下述方式調製偏光薄膜，並比對 檢討漏光部之狀態。 在具備氣體導入管、攪拌裝置、加熱冷卻裝置之容量 lOOOcc的反應器，投入n-丁基丙烯酸酯（ΒΑ)68·5重量份、 丙烯酸（ΑΑ)1重量份、2-羥乙基甲基丙烯酸酯（2ΗΕΜΑ)0. 5 重量份、苯甲基曱基丙烯酸酯（βΖΜΑ)30重量份、以及作為 反應溶劑之醋酸乙基（ΕΑ)1〇〇重量份，並將氮氣導入該反 應器内，以氮氣取代反應器内之空氣，並將反應液之溫度 維持在65°C。 接著，將作為反應起始劑之偶氮二異丁晴 、 （2, 2’ -azobisisobutyronitrile，AIBN)〇. 1 重量份溶解 在醋酸乙酯中，製成聚合起始劑之50重量％溶液。 將以上述方式調製之聚合起始劑之50重量％溶液’滴下 而添加在導入原料成分且加熱至65°C之反應液中，持続進 行10小時反應。 經過10小時後’將所得之黏著劑溶液之固形份濃度調 製為15重量％，相對於該溶液之固形份1〇〇重量份’將作 為三官能性之三曱基醇丙烷的曱苯二異氰酸酯（Toiy1 ene 20 320244 200912400 diisocyanate)附加物1·2重量份稀釋於5〇重量份之錯酉分 乙酯而成之稀釋液添加在上述反應液中，調製成塗布液 將該塗布液依上述同樣方法塗布在易剝離性邱丁薄 膜’使乾燥厚度成為2 5 /z m，去除溶液後，轉印在偏光薄 膜並且將剝離性PET配置在塗布面，在2 3 °C下熟成γ天 準備SgOmmxSISmmxl.lmmt之坡螭基板，一邊將易剝離 性PET予以剝離，一邊將如上述方式調製之附有黏著劑層 之偏光薄膜貼附在玻璃基板之兩面，使之成為正交偏光位 (45、135 )，並且在溫度50°C、線壓5Kg/cm之條件下熱 壓接於玻璃基板後，在室溫下放置丨小時。 將顯示器螢幕BENQ PF91G之偏光板，以所製得之偏 光板替換。將顯示器螢幕連接在個人電腦，並設為全晝面 黑色顯示，使用亮度計rISA一c〇L〇R_CD(Highland公司（有） 製）測定暗室下顯示器螢幕之亮度時，.在玻璃基板之緣部並 未形成圓弧狀之漏光部。 測定該黏著劑層之凝膠份率時得知其凝膠份率為83 %，可知該黏著劑層為軟質。 再者，由於異氰酸酯之反應率通常未達63%，因此從 機率論來看，可形成存在於交聯劑内之交聯構造的活性3 個異氰酸酯基之中，2個係與位於共聚合體側鏈的官能基 &並开v成黏者劑層’但3個異氰酸g旨基中之約1個異氰 酉文酉曰基並未進行反應而殘存於交聯劑中。因此，該聚異氰 酸酯化合物交聯劑使共聚合體成為二點結合狀態，該共聚 合體因交聯劑所產生之拘束力低，而該黏著劑為軟質。 21 320244 200912400 接著，將顯示器螢幕在60°C、濕度95%之環境下放置 72小時，以進行偏光薄膜之熱變形促進實驗。然後，在室 溫放置1小時後，在暗室連接在個人電腦並設為全畫面黑 色顯示。使用亮度計RISA-C0L0R-CD8(Highland公司（有） 製）測定全晝面黑色顯示之顯示器螢幕之亮度時，如第2圖 所示從玻璃基板之各緣部確認有面積大且亮度高的圓弧狀 漏光部。在將亮度高於2cd/m2之部分視為漏光部時，寬度 最寬廣之漏光部的寬度⑺相對於破璃基板之長邊⑹ 380mm 為 56.5mm。 因此，該玻璃基板之W/L的俊為〇149，與如上述方 式調製之液晶基板之圓錄的漏光部彳目减，得知該机 之値明顯地變大。 再者，測定與實施例判定之漏光位置相同之位置（距端 部20. 5咖）的亮度⑴，並且測定未產生漏光部分轉暗時之 亮度⑺’而兩者之㈣（X/mi5。該値越料丨表示越 難以看錢光部之存在，可知纽實施例產生更多之漏光。 如此，漏光部轉暗時亮度高之原因，係由於第2圖⑻ 中以符號Ha所示部分的黏著劑中來自苯甲基丙賴之 基並未被固定’來自m丙埽一之基亦完全不會對穿 透第2圖⑻中以符號17a所示部分的光造成純妨礙之 故。 光板，完全未採用本 在前述專利文獻1具體記戴之偏 發明之漏光防止方法的技術。 (產業上之利用可能性） 320244 22 200912400 根據本發明’可減小在大型顯示裝置的緣部產生之圓 弧狀漏光部，而且即使在轉暗時該漏光部之亮度與對偏光 薄膜施加大的内部應力部分的亮度的差亦會變小，漏光部 4乎不施辨識。在大型顯示裝置中，& 了貼附偏光薄膜並 且使圓弧狀之漏光部分不會形成在顯示裝置畫面的緣部， 必須使用極堅牢之黏著劑，即便使用該堅牢之黏著劑，要 在長期間使用中完全防止圓弧狀漏光部的產生也極為困 難’而且顯示裝置晝面變得越大，這種傾向也隨之增大。 本發明係一邊儘可能使該漏光部不會產生，一邊調整 黏著劑層&所形&之漏光部的亮度，而使漏光部不會顯眼。 【圖式簡單說明】 第1圖（A)及(B)係顯示裝置之平面圖及端部剖視圖。 第2圖（A)及(B)係形成圓弧狀漏光部之顯示裝置的平 面圖及端部剖視圖。 【主要元件符號說明】 10 液晶顯示裝置之前面 11 液晶顯示裝置之4個角 15 玻璃基板 i γ 17a 施加應力之黏著劑層 19 偏光薄膜 iga 20 漏光部 21 S 液晶裝置之跨距長度 黏著劑層 (漏光部之）偏光薄膜 緣部 23 320244: The maximum width of the arc-shaped light leakage portion generated at each edge portion tends to become I. Door 2〇t67:f light leakage in the display device is disclosed in Japanese Patent Laid-Open Publication No. Hei. No. Hei. No. 2006-259664 (the patent document 「 discloses "a polarizing plate having an adhesive layer, and a special type of spinning".八有的筚斟# & π , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , In the case of the co-polymerization of the dilute acid benzene vinegar, it is not possible to completely prevent the glazing. The adhesive of the document 1 is also disclosed in the Japanese Patent Application Laid-Open No. Hei 2__259664. It is an object of the invention to provide a light leakage portion which reduces the occurrence of an arcuate light leakage portion at each edge portion of a TN mode liquid crystal display device which is applied to a span length i9 at 320244 6 200912400. There is a method that is also difficult to recognize. Further, the object of the present invention is to provide a display device using the method described below, which reduces the rounding of the edges of the liquid crystal display device having a span length of 19 吋 or more. The occurrence of an arc-shaped light leakage portion, and even if it is formed In the light leakage portion described above, the existence of the light leakage portion is also difficult to recognize. (Means for Solving the Problem), 1'. The present invention is a method for reducing the formation of an arc-shaped light leakage at the edge of the large-sized display device. In the meantime, it is a method of reducing the light leakage of the extended polarizing film of the ΤΝ mode liquid crystal display device having a span length of 19 吋 or more, and forming an arc-shaped light leakage at the edge of the large display device. The adhesive of the extended polarizing film film imparts strength against thermal contraction of the extended polarizing film, so that the maximum 値(w) of each edge of the light leakage arc generated at each edge of the large display device is relatively large ( The ratio (W/L) of the length (L) of the long side of the display device is 以下·· or less, and the side chain is introduced into the hydrocarbon primary key of the adhesive to form a circle formed at the edge of the large display device. When the arc-shaped light leakage portion is darkened, the luminance (χ) is 4 cd/m 2 or less, and the ratio (χ/γ) of the degree (Y) when the portion where no light leakage occurs is 2 〇 or less. a display device that is utilized to reduce A method of forming an arc-shaped light leakage at the edge of the large display crack due to thermal contraction of the extended polarizing film of the TN mode liquid crystal display device having a span length of 19 Å or more is attached to the edge of the large display device The portion is formed into an arc-shaped leak 320244 7 200912400, wherein 'the method is for the adhesive agent against the extended polarizing film to resist the pure (four) strength of the extended polarizing film, so that the large display device is produced The ratio of the maximum 値(7) of each edge of the light leakage arc to the length (L) of the long side of the large display device is 〇", and the side key guides the hydrocarbon of the adhesive. The main chain of the compound is such that the light leakage of the lion in the arc of the large display device is darkened (1) becomes (four)/仏下' and the brightness of the portion that does not produce μ is darkened (Υ) The ratio (χ/γ) is 2〇 or less. In the present invention, even if a polarizing film is attached to a large-sized liquid crystal display device, a light-tight portion formed at each edge portion due to shrinkage of the extended first film can be changed by using a strong adhesive having a high strength. small. The adhesive strength of the adhesive is mostly derived from the cross-linking structure in which the chain molecules forming the labeling agent are bound to each other, and the cross-linking agent of the (four) energy group is used in the present invention, wherein two or more functional groups are used. The viscous (four) molecules with chains are bound to each other to impart fastness to the adhesive itself. Even if the fast hexagram is used as described above, an arc-shaped light leakage portion is formed at each edge portion of the glass substrate on which the liquid crystal device is formed. However, according to the present invention, the maximum width of the arc-shaped light leakage portion can be reduced from the long side length (L) of the glass substrate to be very narrow as described above = so that even with a strong (four) agent attached to the film In the liquid crystal display device of a large-sized kneading surface, an arc-shaped light leakage portion is formed along each edge portion as described above, but the brightness (1) when the arc-shaped light leakage portion thus formed is darkened is 4 cd/mm and When the luminance (7) ratio (4) 〇〇/〇〇 of the portion of the polarizing film that is normally attached to the polarizing film is small, if the luminance ratio is small, the light leakage portion 320244 8 200912400 - is substantially difficult to recognize as the light leakage portion. ^ The light leakage portion is difficult to be recognized as a light leakage portion? p 'The light leakage portion is formed. However, in the present invention, the polarizing film is often made small by using the internal stress of the condensation as much as possible between the ends. 'And the area of the side chain of the adhesive polymer becomes non-brightness, although in reality == energy base' thereby reducing the light leakage portion as a light leakage portion. (4) In the light portion, the light leakage portion is also difficult to be distinguished (the effect of the invention). According to the present invention, in the day-to-day display device on the span length phase, the large-sized liquid light Qiu _f 吏 & The arc-shaped skin and the mt fraction at each edge of the display device become small, and the light leakage portion of the mosquito is not conspicuous. The arc-shaped leak is applied. Next, the specific (4) of the present invention is reduced in frequency by arc-shaped light leakage. Method and display device. The span length (s) of the reduction of the light leakage of the edge of the device is 19 minutes, and the reduction of the light leakage of the present invention*, and the large TN of the present invention are shown in FIG. The mode display is shocked. The higher the usefulness, the longer the span length of the liquid crystal device (8) is equivalent to the _2 ton, the device itself has its driving limit, and the liquid crystal liquid crystal display device is In the foregoing, a plurality of liquid crystal cells of the plurality of liquid crystal cells are arranged on the glass substrate 15.:, the spacer film, the electrode, and the like are disposed 320244 9 200912400 _ on the surface of the glass substrate 15 by an adhesive The layer η is adhered to the polarizing film 19. The polarizing film 19 is extended A synthetic resin film is formed, and a protective thin film (10) having no extension is usually disposed on the front and back surfaces of the polarizing film. The polarizing film 19 having the above configuration is usually disposed on the glass substrate 15 constituting the front and back surfaces of the liquid crystal device. The polarizing film 19 is bonded to the glass plate 15 by the adhesive layer 17 and the polarizing film 19 is an extended film as described above. When heat is applied to the polarizing film 19, heat shrinkage occurs in the center direction of the liquid crystal display device 1 as shown in Fig. 2. However, since the TAC film has no stretched film, thermal stress does not occur and internal stress is generated. The direction of heat shrinkage (the direction in which the internal stress is applied) is different from the direction of the polarizing axis (the central portion of each side of the display device), and the straight line. The polarized light becomes a circularly polarized light due to birefringence, allowing light to pass through, but Since the corner polarization axis is similar to the contraction direction, it is less likely to generate birefringence and is less likely to leak light, so that an arc-shaped light leakage portion is formed on each side of the display device. In the arc-shaped portion where strong internal stress exists, the function of the polarizing film is impaired, and arc-shaped light leakage occurs. In Fig. 2(B), the part of the polarizing function damaged by internal stress is symbolized丨% indicates that the direction and intensity of heat shrinkage are indicated by arrows. As shown in Fig. 2(B), the light leakage is a portion of the internal stress which is thermally contracted by the extension of the polarizing film 19 to the influence of heat. In the arc-shaped portion where there is a large stress inside, the characteristic of the polarizing film is changed by the stress 320244 10 200912400 -^, in which the polarizing film does not function as a polarizing film' and should be shielded by the polarizing film 1 g The light penetrates the liquid crystal display device. In the method for reducing light leakage of the display device of the present invention, first, in order to reduce the light leakage area, a light-tight portion 20 formed in an arc shape is concentrated at the end portion by using a strong adhesive ( Corner). The size of the arc-shaped light leakage portion 2 is the largest (W) from the edge portion 21 in the central portion of the long side (L) of the liquid crystal display device. In the present invention, the polarizing film is adhered to the glass substrate by using a strong adhesive, and the ratio of the maximum 値(w) of the light leakage arc from each side to the long side (L) of the liquid crystal display device is used. /L) is usually 〇1 or less, and more preferably 1 is 0·0 6 or less. The adhesive used herein is a polymer obtained by (co)polymerizing a monomer having an ethylenic double bond and having a hydrocarbon chain as a main chain, wherein a monomer having a double bond derived from a propylene group is used (total The polymer obtained by the polymerization has good transparency. In the main chain of the (co)polymer which is a main component of the adhesive, for example, a polar group such as a hydroxyl group, a mercapto group (salt thereof), an amino group, an alkylamine group, an alkoxy group, or a decyl group is introduced. a side chain; and, for example, a saturated cyclic hydrocarbon such as a cycloalkyl group having a linear or cleavage, a cycloalkyl group which may have a substituent, a base group derived from a cyclic compound such as a stupid group having a substituent, and benzoquinone The base or the like is derived from a side chain of a nonpolar group such as a group of a cyclic compound. The (co)polymer having the main component of the side chain as an adhesive usually has a weight of from 1,000,000 to 2.5 million, preferably from 120,000 to 2,000,000. 11 320244 200912400 Average molecular weight. Further, the narrower the molecular weight distribution of the (co)polymer, the more easily the structure of the adhesive layer becomes firm, and the uneven adhesion of the adhesive layer is less likely to occur. Further, the molecular weight distribution (Mn/Mw) of the (co)polymer as a main component of the adhesive is usually in the range of 2 to 20, preferably 4 to 10, by using the adhesion of the molecular weight distribution. The main component (co)polymer of the agent easily forms a firm adhesive layer structure. Further, the (co)polymer which is a main component of the adhesive generally has to maintain good adhesion in an environment in which a polarizing film is adhered, and the glass transition temperature (Tg) of the (co)polymer is usually - It is in the range of 70 to -10 ° C, preferably in the range of -50 to -30 ° C. The glass transition temperature (Tg) of the (co)polymer can be measured by the (co)polymer produced after the (co)polymer is produced, or can be used from the (co)polymerization by the formula of Fox. Body export. The polar side chain or the non-polar side chain of the main chain of the (co)polymer may be directly combined with the rehydrogen main chain constituting the (co)polymer of the adhesive, or may be via-0-C0- a divalent group such as a -C0-0-yl group and the like, or a divalent group of -S- or the like, from -0-P〇2-0-, -〇S〇2-〇- The phosphate or sulfonic acid group is bonded. The (co)polymer having the side chain can be obtained by (co)polymerizing a compound having an ethylenic double bond, and then introducing a desired group into the main chain, or by introducing an ethylene group having a desired group in advance. Monomer (co)polymerization of double bonds is produced. Further, a (co)polymer having a desired group may be produced by arranging a desired base in the (co)polymer produced as described above. The polar side chain such as a hydroxyl group or a carboxyl group of the (co)polymer which is implanted in the main component of the adhesive forming the adhesive as described above not only contributes to the glass substrate and the film of 12 320244 200912400, but also crosslinks When the (co)polymer is a component, it becomes an activity of reacting with the crosslinking agent. - The (co)polymer of the main component of the adhesive forms a cross, and the polymer of the main component of the agent (4) is compounded to form a strong one. The two or two owed ^ have the reverse unit of the polar group, and the weight of the monomer (10) having the (co)polymer is made as the main component of the adhesive, preferably contains ... An amount in the range of up to 10 parts by weight. A crosslinking agent which reacts with the above-mentioned polar group to form a crosslinked structure, and a compound which is a plurality of groups in which a polar group is reacted with a polar group, can be used as an example of the base of the reaction. The present invention can be exemplified by a net § thiophene group, an isocyanate group, a genus number, etc. The hexacycline metal chelating group used in the present invention is preferably used in the present invention, but is preferably used in the present invention. The crosslinking agent 4= has 4 or more poles which contribute to the crosslinking reaction A cross-linking agent. The internal-based _ is a polar group-based epoxy group which is a prosperous compound which contributes to the parent-linked reaction, and is difficult to use, and it is difficult to use four or more rings in one molecule. A compound of an oxy group is used as a crosslinking agent. The epoxy group of the hexa-linking agent reacts with, for example, S or a carboxyl group which is implanted in the primary bond of the adhesive to form an intermolecular crosslinked structure and form a strong adhesive. Although the structure of the cross-linking structure which is introduced into the cross-linking agent is completely bonded, in the present invention, a cross-linking agent containing four or more epoxy groups is used, and the reaction of the epoxy group is considered. Efficiency, even if a crosslinking agent having, for example, four epoxy groups is used, the reaction rate of the epoxy group is usually at most only about 69% to 77%, and the introduced epoxy group does not all react. When there are four epoxy group crosslinkers, the average of three of the four epoxy groups is 320244. 13 200912400 - The epoxy group is bonded to the polar group implanted in the main chain of the adhesive. a plane. In the adhesive combined by the three points, it is assumed that there is a combination The hard majority of the bond determined by the two points, the free movement of the main chain of the adhesive is conspicuously restricted to form a strong adhesive layer, and 'in order to obtain the strength of the heat shrinkage of the extended polarizing film resistant to the present invention, Preferably, the crosslinking agent is used in an amount of 〇〇·〇5 to 0. 20 parts by weight with respect to the adhesive polymer, and the crosslinking agent layer having a high crosslinking density as described above is formed, and the gel is used. The fraction is set to be 85 to 95%. In addition, as a crosslinking agent formulated in the adhesive layer, there is an example of using a compound of the isocyanate (P〇lyjs〇Cyanate). When the polyisocyanate is capable of reacting, the reactivity of the two isocyanate groups is relatively low, and the reactivity of the one isocyanate group is lowered, and as a result, the reaction rate of the trifunctional isocyanate usually does not reach 65. %. Therefore, when a trifunctional polyisocyanate is used, only two isocyanate groups of the trifunctional polyisocyanate compound are bonded to the two main chains of the (co)polymer to form the adhesive, and the adhesive layer cannot be suppressed. Adhesive (co)polyk.. movement of the bond within the adhesive layer, the adhesive layer becomes soft and is easily pulled closer to the central portion of the liquid crystal as the polarizing film is thermally contracted, thus The size of the light leakage portion shown in Fig. 2, that is, the W/L is larger. In the method for reducing light leakage of the present invention, the stretched processed polarizing film is also used, so that even if the adhesive layer is made relatively strong, the arc-shaped light leakage portion 20 cannot be prevented from being formed on the display due to thermal contraction of the polarizing film. The edge of the device. However, the ratio of the maximum width W of the light-retaining portion 20 to the length L of the display device in accordance with the present invention is 14 320244 200912400, (W/L) is 0.1 or less, preferably 0. Below 06, and compared with the case of using, for example, a trifunctional polyisocyanate compound, the area _ of the light leakage portion 20 becomes smaller. Further, in the method for reducing light leakage of the present invention, a group having an aromatic ring is implanted in a main chain of a (co)polymer constituting the adhesive. It is understood that the base having the aromatic ring is introduced into the main chain constituting the adhesive, so that the polarizing film 19 is elongated by the heat shrinkage, and the side chain of the annular structure constituting the component of the adhesive is aligned. The transmittance of the light leaking portion 20 is reduced. Further, since the monomer which introduces the aromatic ring into the side chain has a high temperature sensitivity and a high temperature, the elastic modulus of the adhesive polymer is lowered, so that the stress caused by the thermal contraction of the polarizing plate can be alleviated. Thus, in order to lower the elastic modulus of the adhesive at a high temperature and to make it an adhesive having a high hardness and a high cohesive force at a normal temperature or a normal use temperature range, the aromatic ring is introduced into the glass of the monomeric homopolymer of the side chain. The transfer temperature is preferably from -25 ° C to 10 ° C. Further, the side chain having an aromatic ring is usually from 20 to 60% by weight, preferably from 20 to 60% by weight, based on 100% by weight of the adhesive polymer other than the main chain. If it is in the range of 30 to 40% by weight, the light leakage can be made more inconspicuous. Further, it is considered that in the adhesive layer thus oriented, about one of the functional groups of the tetrafunctional crosslinking agent remains without reaction, and the adhesive layer is elongated by the heat shrinkage of the polarizing film 19, and remains. A portion of the functional group is bound to a portion of the functional group unreacted in the functional group of the adhesive resin implanted in the adhesive layer, so that the stress-applied adhesive layer 17(a) is more rigid and applied In the adhesive layer 17(a) having this stress, a group having an aromatic ring set to a fixed direction by 15 320244 200912400 is fixed. Therefore, in FIG. 2(A), an arbitrary point (X) in the light leakage portion 20 and an arbitrary point (Y) in a portion where the polarizing film 19 is disposed are determined, and when the light leakage portion is darkened when the display device is turned dark, The ratio (X/Y) of the luminance (X) and the luminance (Y) when the portion where no light leakage occurs is 20 or less, preferably 10 or less. This is because the base having the aromatic ring present in the stress-applied adhesive layer 17 (a) relaxes the stress caused by the thermal contraction of the polarizing film, and slowly aligns to shield the transmitted light. At least a part of the difference between the luminance X and the luminance Y becomes extremely small, and it is difficult to visually recognize the existence of the light leakage portion due to thermal contraction of the polarizing film. The method for reducing light leakage according to the present invention as described above is such that a firm adhesive layer is formed to reduce the area of the light leakage portion, and the difference between the brightness of the light leakage portion and the brightness of the portion where the polarizing film is disposed is reduced. Even if the light leakage portion is formed by the stress generated by the thermal contraction of the polarizing film 19, the area of the light leakage portion can be remarkably reduced, and the brightness of the light leakage portion and the polarized light can be changed due to the darkening. The difference in brightness between the portions of the film is extremely small, and is small, so that the specific effect of the arc-shaped light leakage portion can hardly be recognized. (Embodiment) Next, an exemplary embodiment will be described with respect to the method for reducing light leakage of the present invention, but the method of the present invention is not limited by the embodiment. Further, the measurement conditions of the gel permeation chromatography (GPC, Gel Permeation Chromatography) of the present invention are as follows. Device 16 320244 200912400 manufactured by Tosoh Corporation, HLC-8120 column G7000HXL xl branch GMHXL x2 branch G2500HXL xl sample concentration: 1.5mg/ml (diluted with tetrahydrofuran) mobile phase solvent: THF flow rate: 1. 0 ml/mi η Temperature: 40 ° C (Example 1) A copolymer having a weight average molecular weight of 1.4 million as determined by colloidal permeation chromatography was produced by a solution of ethyl acetate as a reaction solvent according to a usual method. (A). The molecular weight distribution (Mn/Mw) of the copolymer (A) is 5 主 in the main chain of the copolymer (A) consisting of hydrocarbon, and the monomer having -CH2CH2CH2CH3 is bonded via -C0-0-. 5重量%, and 2% by weight of a monomer having -CH2-CH2-OH, and having a monomer having a -C00H group of 0.5% by weight and a monomer having -CH2-C6H5 via -C0-0- Copolymerization is carried out in an amount of % by weight. The glass transition temperature (Tg) measured for this copolymer (A) was -34 V. After adjusting the concentration of the obtained copolymer (A) in an ethyl acetate solvent to 15% by weight, an epoxy-based tetrafunctional crosslinking agent (compound name: N, N, was added to 100 parts by weight of the solid portion of the solution). N,N-tetraglycidyl-m-diphenylbenzene 17 320244 200912400 Diamine, trade name: TETRAD0 X, manufactured by Mitsubishi Gas Chemical Co., Ltd.) 1 part by weight, and mixed in order to prepare an adhesive coating liquid. The obtained adhesive coating liquid was applied onto a peelable PET film to a dry thickness of 25/zm, and after the solution was removed, it was transferred to a polarizing film and aged at 23 ° C for 7 days to produce an adhesive layer. Polarized film. A 390 mm x 315 mm x 1.1 mm glass substrate was prepared. The polarizing film with the adhesive layer prepared as described above was attached to both surfaces of the glass substrate while peeling off the easily peelable PET, thereby forming an orthogonal polarizing position (45. 'And after being thermocompression bonded to the glass substrate at a temperature of 5 Kg/cm under the line pressure, it was allowed to stand at room temperature for 1 hour. θ is replaced with the polarizer of the display screen BENQ PF91G, and the polarizer is installed. Connect the monitor screen to a personal computer and set it to full 昼 = black display 'Using the brightness meter RISA-C0L0R-PF91G (manufactured by Highland) to measure the brightness of the display screen under the darkroom, at the edge of the glass substrate 卩An arc-shaped light leakage portion is not formed. The coating layer, such as a glass substrate with a polarizing film produced by a crucible method, scrapes the adhesive layer, and the gel fraction of the adhesive layer is 91%. In view of the fact that Y has a reaction rate of 69 to 77% due to the epoxy group, the active epoxy group which forms the crosslinked structure existing in the crosslinking agent can form a tough one and is located in the copolymer (A). The functional group in which the side chain of the side chain is bonded and reacted, but about one of the four epoxy groups does not remain in the cross-linking agent in the state of the ruthenium-oxygen group. 72 hours, [, will be placed in the environment of 60 ° C, humidity 95% of the environment to carry out the thermal deformation of the polarizing film. Then, after standing at room temperature of 320244 200912400 for 1 hour, it was connected to the personal computer in the dark room and set to full black display. When the luminance of the display screen of the full-face black display is measured by the luminance meter RISA-C0L0R-CD8 (manufactured by Highland Corporation), as shown in Fig. 2, arc-shaped light leakage is formed at each edge portion of the glass substrate. unit. When the brightness of the visually identifiable light leakage (up to 2 cd/m2) is set as the light leakage portion, the width (W) of the light leakage portion having the widest width is 20.5 mm with respect to the long side (L) of the glass substrate of 380 mm. Therefore, the W/L 该 of the glass substrate is 0.054, and it is found that the W/L is extremely small as compared with the arc-shaped light leakage portion of a general liquid crystal substrate. When the luminance (X) of the portion where the light leakage occurred was measured, and the luminance (Y) when the light leakage portion was not darkened was measured, the brightest portion of the light leakage portion was 4 cd/m 2 , and the slightly bright portion was 2 cd/m 2 , which was not generated. The luminance (X) of the light leakage portion is 0.2 cd/m2, so the enthalpy of (X/Y) is in the range of 20 to 10. The brightest portion is almost covered by the frame of the display device, so that the substantial (X/Y) of the display device is 10. The closer the 値 is to 1, the more difficult it is to see the presence of the light leakage portion, and the X10 of (X/Y) indicates that the light leakage is particularly small as compared with the conventional display device. Although the light leakage portion is formed as described above, the reason why the brightness of the light leakage portion is lowered when dimming is because the internal stress is concentrated as much as possible at the end portion by forming a strong adhesive layer, and as described above in the thermostatic bath When heating and causing thermal contraction of the polarizing film, the adhesive of the portion indicated by the symbol 17a in Fig. 2(B) is pulled toward the center of the liquid crystal display device with the thermal contraction of the polarizing film, and -CH2-C6H5 In the copolymer (A) constituting the adhesive via -C0-0-, in this state, 19 320244 200912400 remaining in the crosslinking agent, the partial portion of the siloxane group reacts, and copolymerization with the residual The polar group of the complex (4) forms a new crosslinked structure, and the aligned na is fixed in the adhesive for adhering with the symbol 1 as shown. • Since the aligned 2_CIl2-C6H5 exhibits an alignment property, a part of the light to be penetrated through the light leakage portion is blocked by the adhesive-CH2_C6h5 group, thereby preventing the light from penetrating, so that the brightness of the light leakage portion is changed according to the method of the present invention. low. In order to compare the above points, the polarizing film was prepared in the following manner, and the state of the light leakage portion was compared. In a reactor having a gas introduction tube, a stirring device, and a heating and cooling device having a capacity of 1000 cc, 68 parts by weight of n-butyl acrylate (、), 1 part by weight of acrylic acid, and 2-hydroxyethyl methyl group were charged. Acrylate (2 ΗΕΜΑ) 0.5 parts by weight, 30 parts by weight of benzyl hydrazide acrylate (β ΖΜΑ), and ethyl hydrazine (ΕΑ) 1 〇〇 by weight as a reaction solvent, and introducing nitrogen into the reactor The air in the reactor was replaced with nitrogen, and the temperature of the reaction liquid was maintained at 65 °C. Next, 1 part by weight of azobisisobutyl bromide and (2, 2'-azobisisobutyronitrile, AIBN) as a reaction initiator were dissolved in ethyl acetate to prepare a 50% by weight solution of a polymerization initiator. The 50% by weight solution of the polymerization initiator prepared in the above manner was dropped and added to the reaction liquid which was introduced into the raw material component and heated to 65 ° C, and the reaction was carried out for 10 hours. After 10 hours, the solid content of the obtained adhesive solution was adjusted to 15% by weight, and the solid part of the solution was used as the trifunctional tridecyl alcohol propane. (Toiy1 ene 20 320244 200912400 diisocyanate) Addition 1·2 parts by weight of a diluted solution obtained by diluting 5 parts by weight of erroneous ethyl ester was added to the above reaction liquid to prepare a coating liquid. The method was applied to a peelable chewable film to make the dry thickness to 2 5 /zm, and after removing the solution, transfer to a polarizing film and dispose the peelable PET on the coated surface, and prepare the SgOmmxSISmmxl at 235 ° C for γ days. The lmmt-plated substrate is peeled off, and the polarizing film with the adhesive layer prepared as described above is attached to both sides of the glass substrate to make the orthogonal polarizing position (45, 135). And it was thermocompression-bonded to the glass substrate under the conditions of the temperature of 50 degreeC and the linear pressure 5Kg/cm, and it was set to the room temperature for 丨 hours. The polarizer of the display screen BENQ PF91G was replaced with the polarizing plate produced. Connect the monitor screen to the personal computer and set it to full black display. Use the luminance meter rISA-c〇L〇R_CD (Highland (manufactured)) to measure the brightness of the display screen under the darkroom. At the edge of the glass substrate. The portion does not form an arc-shaped light leakage portion. When the gel fraction of the adhesive layer was measured, it was found that the gel fraction was 83%, and it was found that the adhesive layer was soft. Further, since the reaction rate of the isocyanate is usually less than 63%, it is possible to form the active three isocyanate groups present in the crosslinked structure in the crosslinking agent from the viewpoint of probability, and the two systems are located on the side of the copolymer. The functional group of the chain & and v is the adhesive layer', but about one of the three isocyanate groups is not reacted and remains in the crosslinking agent. Therefore, the polyisocyanate compound crosslinking agent brings the copolymer into a two-point bonding state, and the copolymer has a low binding force due to the crosslinking agent, and the adhesive is soft. 21 320244 200912400 Next, the display screen was placed in an environment of 60 ° C and a humidity of 95% for 72 hours to carry out a thermal deformation promoting experiment of the polarizing film. Then, after standing at room temperature for 1 hour, it was connected to a personal computer in a dark room and set to a full-screen black display. When the luminance of the display screen of the full-face black display is measured using a luminance meter RISA-C0L0R-CD8 (manufactured by Highland Co., Ltd.), as shown in Fig. 2, it is confirmed from the edge portions of the glass substrate that the area is large and the brightness is high. Arc-shaped light leakage unit. When the portion having a luminance higher than 2 cd/m2 is regarded as a light leakage portion, the width (7) of the light leakage portion having the widest width is 56.5 mm with respect to the long side (6) 380 mm of the glass substrate. Therefore, the W/L of the glass substrate was 149, and the light leakage portion of the liquid crystal substrate prepared as described above was significantly reduced, and it was found that the machine became significantly larger. Further, the luminance (1) at the same position as the light leakage position determined in the example (the distance from the end portion of 2. 5 coffee) was measured, and the luminance (7)' when the light leakage portion was dimmed was measured, and (4) (X/mi5). The more difficult it is to see that the more difficult it is to see the presence of the light portion, it is known that the New Embodiment produces more light leakage. Thus, the reason why the light leakage is dark when the light leakage portion is dark is due to the portion indicated by the symbol Ha in Fig. 2 (8). The benzylidene-based group in the adhesive is not fixed. The radical from the substrate is also completely impeded by penetrating the light of the portion indicated by the symbol 17a in Fig. 2 (8). In the light panel, the technique of the light leakage prevention method of the invention disclosed in the above-mentioned Patent Document 1 is not used at all. (Industrial use possibility) 320244 22 200912400 According to the present invention, it is possible to reduce the occurrence of the edge of a large display device. In the arc-shaped light leakage portion, even when the light is dimmed, the difference between the brightness of the light leakage portion and the brightness of the portion where the internal stress is applied to the polarizing film is small, and the light leakage portion is not recognized. In a large display device. , & attached The light film and the arc-shaped light leakage portion are not formed on the edge of the screen of the display device, and it is necessary to use a very strong adhesive. Even if the adhesive is used, it is necessary to completely prevent the arc-shaped light leakage portion during long-term use. The generation of the adhesive device is also extremely difficult, and the tendency of the display device to become larger is increased. The present invention adjusts the adhesive layer & The light leakage portion is not bright. The first embodiment (A) and (B) are a plan view and an end cross-sectional view of the display device. Fig. 2 (A) and (B) A plan view and an end cross-sectional view of a display device in which an arc-shaped light leakage portion is formed. [Description of main component symbols] 10 Front surface of liquid crystal display device 11 Four corners of liquid crystal display device 15 Glass substrate i γ 17a Adhesive layer 19 to which stress is applied Polarizing film iga 20 Light leakage portion 21 S Span length of liquid crystal device Adhesive layer (light leakage portion) Polarized film edge portion 23 320244