200827787 九、發明說明 【發明所屬之技術領域】 本發明係有關於超低遲滯光學膜以及該光學膜於偏片 保護膜之應用。 【先前技術】 液曰曰”、、員不态（LCDs)已普遍應用於個人電腦監視器、數 位相機和行動電話及大尺寸之電視上。在LCD面板中，偏 光板為液晶顯示器之基礎零件之—。偏缺⑽Μ·)是一 種只允許某方向的光線才能透過的光板，於製作液晶板過 程中，必須上下各用-片，且成交錯方向置入，主要用途 =在有，場與無電場時使光源產生位相差而呈現明暗的狀 態，以顯示字幕或圖案。隨著lcd用量的增加，偏光板需 求與日倶增。偏光膜的極化作用係由一透明聚合物膜中有 指向性之光非等方向性吸收體所致，例如聚乙烯醇 的偏振片是將碘或一種二色染料吸附在聚乙烯醇臈中後， 猎延伸使其具單軸之指向性。隨著LCD產品使用範圍的擴 大，對偏光產品的濕熱工作條件的要求越來越苛刻，以這樣 材料做的偏光片在溼熱的可靠性測試中容易地遇到或尺^ ，縮的問題，光學特性劣化U是由於㈣分子結構在 高溫高濕的條件下易於破壞之故，所以偏光膜需要S二面 保護膜作為支撐與保護以財它㈣久性及機械強度了通 常習用之保護膜為三醋酸纖維素（TAC)。這 ： 特性必需要有高的絲率、低雙折射、優㈣熱、冷\光、 0954-A21972TWF(N2);P5495〇〇97TW；esm〇nd 200827787 濕氣抵抗力和光學上之均勻性，也就是說須無外物或可視 斑紋之瑕疵。而以溶劑法塗佈之三醋酸纖維素保護膜因其 透光度、外觀佳和容易與偏光膜黏貼之故而習用至今。 由於大尺寸LCD之電視逐漸普及’已要求TAC保護膜有更低的雙折 射性質。目前TAC之R〇值小(in-plane -retardation)，但Rtli值仍大 (out-of-plane retardation)。此Rth值將導致LCDs上有不完美的光學的補 償效應(例如大角度下有黑色和白色的對比下降和顏色改變(c〇1〇rshift) • 問題發生。因此她值需要愈小愈好，特別是IPSOn-plane switching^ 模式LCD上。通常，聚合物有它自己的雙折射，其值隨著聚合物中之 分子鏈定向性愈高而增加，而Rth值是很難降低的，因聚合物之分子 鏈易傾向于在同平面上(in-plane)排列之故。因此，為了降低雙折射，一 般使用補償之方法，例如日本最近研發了零雙折射(zer〇_birefringenee)' 之聚合物(W02006098517 ; JP2006096793)，其透過使用負雙折射無機 物晶體或添加劑來補償聚合物的正雙折射，以調製出零雙折射之聚合 •物混合物。也有發表低的雙折射之環聚烯聚合物(Cyclo 〇lefm Polymer) (JP2006124628; US2004099973; JP2004168063) ? 性主鏈和支鏈若使餘PVA偏光片保護膜時，他墙乎難崎上親水 性的PVA上。 【發明内容】 本發明的主要目的就是提供一種超低遲滯光學膜，以 改善液晶顯示器在大角度下的光學補償效應。 、 為達上述與其他目的，本發明之超低遲滯光學膜主要 0954-A2t972TWF(N2)；P54950097TW；esmond 6 200827787 包括·透光樹脂，其具有三度空間之交鏈結構；以及，奈 米級金屬氧化物粒子分散於該透光樹脂中；其中，該光學 膜之平面内光遲滞性(R〇;in_plane retardati〇n)在〇〜2nm之 門平面外光遲滯（Rth; 〇ut-of_plane retardation)值接近 Onm 〇 本發明更提供一偏光板，主要包括一偏光片、以及上 述之超低遲滯光學膜設置於偏光片之至少一表面，以作為 偏光片保護膜。 • 【實施方式】 _本發明之超低遲滯光學膜的主要成份是高透光樹脂及 均句分散於該透光樹脂層之表面及内部之奈米級金屬氧化 物粒子之混成材料，又可稱之為奈米複合材料。 如第1圖所示，本發明之超低遲滯光學膜10為一複合 材料’其組成包括透光樹脂l〇a與均勻分散在樹脂中的奈 米級金屬氧化物粒子l〇b。本發明所使用之透光樹脂l〇a Φ 經反應固化後是呈三度空間交鏈之結構，因此分子鏈幾乎 70全热指向性’即為具備光學之等方向性，所以為優異之 零雙折射透明材料。此外，奈米級粒子1〇1)均勻分佈在透 光樹脂10a中除了本身具有光學上的等方向性，亦可打亂 分子鏈之指向性，因而增加光學上的等方向性。另一方面， 奈米級粒子l〇b的摻入尚可提高硬度、熱尺寸安定性、親 水性、並降低濕氣滲透率。 本發明所用之透光樹脂具有90%以上的透光率，主要 係為環氧樹脂或丙烯酸酯樹脂，適用的環氧樹脂包括具有 0954-A21972TWF(N2)；P54950097TW；esmond 7 200827787 環氧基(oxirane dng)之單體、寡聚物、或聚合物。較佳的 具體例包括：雙酚A型環氧樹脂（bisphen〇1 A ep〇xy resin)、 又酉刀F環氧树月日(biSphen〇i p ep〇Xy resin)、雙酴$型環氧樹 脂(bisphenol S epoxy resin)、酚醛 N〇v〇lak 環氧樹脂、曱紛 Novolak環氧樹脂、脂環式環氧樹脂、或是含氮或氫化之 奈型裱氧樹脂、雙酚S型環氧樹脂與聯苯型環氧樹脂等 等。這些環氧樹脂可以單獨或混和使用，端視所需求之加 工及物性來作適當的選擇與調配。所用之丙烯酸酯樹脂包 括其單體、寡聚物或聚合物，較佳的具體例包括：環氧丙 烯酸酯、聚胺基曱酸脂丙烯酸酯、聚酯丙烯酸酯、丨，6-六 二醇二丙烯酸酯（HDDA)、羥乙基甲丙烯酸酯（hema)等 等。同樣的這些丙烯酸酯樹脂可以單獨地或作組合地使 用，甚至與上述之環氧樹脂搭配使用，端視所需求之加工 及物性來作適當的選擇及調配。 本發明之透光樹脂更包括硬化劑，該硬化劑可分為熱 起始劑與紫外光起始劑兩大類，均可用單獨或以混合方式 用於本發明。對環氧樹脂系統而言熱起始劑可選擇酸酐和 部份地被酯化的酸酐類型硬化劑，如六氫鄰苯二曱酸醉 (hexahydrophthalic anhydride ; HHPA)、四氫鄰苯二曱酸軒 (tetrahydrophthalic anhydride ; THPA)、曱基四氫鄰苯二曱 酸酐（methyl tetrahydrophthalic anhydride ; MTHPA)、曱基 六氫鄰苯二曱酸酐（methyl hexahydrophthalic anhydride ; MHHPA);三乙烯二胺；咪唑化合物，如2-乙基-4-曱基味 唾、2-曱基口米峻；石粦化合物，如三苯基石舞 0954-A21972TWF(N2)；R54950097TW；esmond 8 200827787 (triphenylphosphine)、 四苯基硼酸四苯基膦 (tetraphenylphosphonium tetraphenylborate)、〇-二乙基二石荒 代 _ 酸酯（o-diethylphosphoroditliioate);四級敍鹽等。而紫 外線起始劑可選擇陽離子型之金屬化合物，如三芳基硫六 氟銻酸鹽(^1^巧18111口11011111111116叉&^1101'03111；1111011如）、三芳基 硫六敗鱗酸鹽（triarylsulphonium hexafluorophosphate)、二 芳基碘鹽等。對丙烯酸酯樹脂系統而言紫外線起始劑可選 擇自由基型之光起始劑，如g同(ketone)系列、石粦(phosphine) 系列、indonium鹽類等。紫外線硬化劑··環氧樹脂/丙烯酸 酯樹脂的重量比較佳在〇·〇3 : 0.15之間，更佳在〇.〇5 : 0.1 之間。熱硬化劑：環氧樹脂/丙烯酸酯樹脂的重量比較佳在 〇·6 : 1.3之間’更佳在〇·9 : I]之間。 本發明之透明樹脂可視需要加入其他傳統常用的添加 劑’例如可添加塑化劑，以增加透明樹脂之加工性、延展 t生與了用生，其添加量一般在1〇〜5〇 phr (per hundred resin) 之間。 相較於傳統三醋酸纖維素（TAC)線性的分子鏈結構， 本發明之樹脂系統之分子在反應後是呈三度空 間交鏈之結 構’因此分子鏈幾乎完全無指向性，而具備光學之等方向 性’所以為優異之零雙折射的透明材料。再者，交鏈結構 之熱尺寸安定性較佳，而且根據不同之配方調製可以獲得 硬化物之破璃轉移溫度介於80〜190°C之間，如此可獲得熱 尺寸安定性很好的透明光學膜材料。 〇954-A^72TWF(N2);P5495〇〇97Tw；esm〇nd 200827787 本發明之奈米金屬氧化物粒子的平均粒徑在1〜5〇奈 米之間，更佳者，可介於5〜20奈米之間。由於奈米粒子粒 徑小於50奈米而且均勻分散於透光樹脂層中，因此光線行 經奈米複合材料不會被散射及反射，可以達到9〇%以上的 透光率（全透光率）。適當的奈米金屬氧化物粒子包括但不 限於：二氧化矽（Si〇2)、二氧化鈦(Ti〇〇、二氧化錘（Zr〇0、 氧化鋁（Ai2〇3)、氧化鋅（Zn〇)氧化鎂（Mg〇)等。上述之奈 米粒子除了可以單獨使用以外，亦可為兩種以上混合使用。 由於奈来金屬氧化物粒子之熱膨脹係數較低，所以本 發明之奈米複合材料之熱膨脹係數較一般習知之熱塑性光 學膜為低’如此可以獲得平整度及熱尺寸安定性很好的透 明光學膜。另外，傳統上為了保護偏光板的表面，一般皆 會在偏光板上塗佈一層約厚5〜1〇μιη的硬質層（hard c〇at layer)，材質通常為環氧樹脂或丙烯酸酯樹脂。而本發明添 加之奈米金屬氧化物粒子本質上就具有之很高硬度之特 性，可以補強樹脂低硬度的弱點，所以本發明之奈米複合 材料之硬度遠較一般習知之熱塑性光學膜為高，如此可以 獲得表裡均一高硬度(鉛筆硬度大於3H)及耐摩耗的透明光 學膜，而不需額外的硬質層。此外，奈米金屬氧化物粒子 可增加材料的親水性，以增加與偏光片間之貼合接著強度。 奈米粒子的含量較佳在5〜50重量％之間，更佳在1〇〜3〇 重量％之間（以光學膜之總重為基準)。根據本案發明人之研 究顯示，只要奈米粒子的尺寸夠小，其含量多寡並不會嚴 重影響到透光率，因此雖然一般不需要，但奈米粒子的含 0954-A21972TWF(N2) ：P54950097TW；esmond 10 200827787 量也有可能超過5 0重量％。此外，奈米粒子的來源可選擇 商用上之固態粉體或溶液狀態者。 除了上述成分以外，本發明之光學膜亦可加入習用的 抗氧化劑或紫外光吸收劑，以避免保護膜變質並確保偏光 板的可靠度。舉例而言，加入紫外光吸收劑後可吸收波長 3 80nm以下的紫外光。抗氧化劑與紫外光吸收劑可單獨或 同時添加，一般的添加量約為〇·1-3重量％(以光學膜之總 重為基準）。 • 第2圖繪示一種可用來製作上述光學膜之裝置。應注 意的事，該圖之裝置僅用來舉例說明，本發明之光學膜不 限於由此種裝置所形成者。首先，將所有原料依配方比例 秤好置入混練槽12中均勻混合形成漿料。根據本發明，此 漿料可以是無溶劑（固含量100%>或含溶劑系統（固含量40 重量％以上）；較佳者，漿料的黏度介於200〜6000 cp之間， 以利後續的塗佈作業。漿料混合均勻後注入塗佈裝置13 (滾 輪或模頭）中以設定之厚度精確地在離型承載膜14上塗佈 ® 之，塗佈後之離型承載膜14經由驅動滾輪15之帶動以恆 定的速度，約0.5到10 m/rnin的速率通過加硬化裝置16， 如熱烘箱或紫外輻照區域，使塗層硬化成形後經捲取滾輪 17捲取之。所形成之透明光學保護膜如18所示，在物性 及成本雙重考量下其適宜之厚度介於1〇〜ι〇〇μπι之間，較 佳在20〜80 μπι之間。 離型承載膜14可為鏡面不鏽鋼帶或熱塑性膠膜，如氨 基曱酸脂樹脂、丙烯酸酯的樹脂、聚酯樹脂、聚乙烯醇、 0954-A21972TWF(N2):P5495009丌 W;esmond 11 200827787 乙烯乙晞基醇共聚物、乙烯基氯樹脂、亞乙稀基氣化物樹 月曰、％：卸輕共聚物（MCOC)樹脂、聚碳酸S旨樹脂、聚芳基酉曼 酯(polyarylate)樹脂等。 第3圖繪示本發明之超低光遲滯光學膜作為偏光片保 缦膜之應用。如第3圖所示，偏光板3 0包括一偏光片5 夾在第一保護膜1〇(超低光遲滯光學膜）與第二保護膜2〇之 間。本發明之透明光學保護膜可以設置在偏光片的單面或 上下兩面。因此，第3圖中的第二保護膜20的材質可以是 本發明的超低光遲滯光學膜，但也可以是傳統的保護膜， 例如纖維酯、聚碳酸酯、壓克力、聚酯、聚烯烴、降冰片 烯等。此處所用之偏光片5並無特定的限制，只要其具有 偏光的特性即可，例如是聚乙烯醇（PVA)或多烯（p〇lyene) 偏光片。本發明之透明光學保護膜10，在物性及成本雙重 考量下其適宜之厚度介於1〇〜ΙΟΟμιη之間，較佳在20〜80 μτη之間。此外，在保護膜1〇上可更形成一抗眩膜（八⑺^， _ 厚度較佳約2〜ΙΟμπι之間或一抗反射膜(AR)ll厚度較佳約 〇· 1 〜0·2μιη 之間。 傳統的偏光板由於保護膜的濕氣抵抗力不足而導致偏 光能力劣化，而藉由本發明的透明光學膜可以提高偏光板 的光學可靠度，特別是在高濕度的環境下。在較佳實施例 中’本發明的保護膜可以達到60〜70g/m2/24hr以下的濕氣 滲透率，約為習用之三醋酸纖維素保護膜的1/6左右。 保濩膜10、20可利用透明接著劑或感壓性接著劑與偏 光片5貼合而成。此外，為了增強後續與偏光片貼合接著 0954-A2]972TWF(N2)；P54950097TW；esmoncl 12 200827787 強度，可預作表面處理，如電漿、電暈、底塗（如pu底塗） 等，由於本複合材料之結構與組成，在經過電漿、電暈等 之處理後其表面具有很好之親水性，其水接觸角可小於 15。，如此可增強與本質即親水性之偏光片間之貼合接著強 度。 本發明之偏光板在實際應用時可與其他光學膜搭配使 用，例如反射膜、半穿半反膜、延遲膜（1/2波長與1/4波 長）、視角補償膜等。舉例而言，本發明的偏光板可與一反 • 射膜或半穿半反膜貼合而形成一反射型偏光板或半穿半反 型偏光板；或與一延遲膜貼合以形成一橢圓形或圓形偏振 片；或與一視角補償膜貼合而一廣角偏光板；或者，與一 增亮膜貼合。 本發明之偏光板可以應用在各種顯示器，包括但不限 於：液晶顯示器、有機電激發光顯示器、電漿顯示器等。 例如，如第4圖之液晶顯示器50所示，可將本發明之偏光 板3 0設置在液晶面板40之任一表面或相反兩面。液晶的 ® 型態與驅動方式亦無特別限制，可以是TN(扭曲向歹彳）型液 晶、垂直配向型液晶、IPS(橫向電場切換）液晶等。此外， 液晶面板的構成通常更包含擴散板、稜鏡陣列、背光元件 等，在此不予贅述。 經測試，本發明之超低遲滯光學膜其Ro光遲滯性可 在0〜2nm之間（入射角為-40°〜40°)，Rth光遲滯性則近於 Onm，且透光率不小於90%(全透光率），因此可用來取代傳 統偏光膜之三醋酸纖維素保護膜，來改善液晶顯示器在大 0954-A21972TWF(N2)；P54950097TW；esmond 200827787 角度下有黑色和白色的對比下降和顏色改變(c〇1〇r shift)的 問題。 由以上况明可知，本發明之混成材料具備零雙折射及 高透光率之光學特性外，也同時具備優秀的冷熱、濕氣之 抵抗力，在製程上可用非溶劑法塗佈來製膜，具有光學上 之均勻性、環保及成本經濟性等之優勢。 為瓖本發明之上述和其他目的、特徵、和優點能更明 喊易懂，下文特舉出較佳實施例，作詳細說明如下。實施 例中所使用之奈米粒子為Nissan Chemical公司所生產 之’’MEK-ST” ’為一種甲基乙基酮（MEK)二氧化矽溶膠 (silica sol)’而整體材料配方中之二氧化矽含量控制在15 重量％。 【實施例】 將熱起始劑曱基六氫鄰苯二曱酸針（methyl 鲁 hexahydrophthalic anhydride ; MHHPA)溶在 MEK 二氧化石夕 溶膠中，再加入環氧樹脂ΕΙ^4221(υηίοη Carbide)及塑化劑 Triol(Union Carbide)形成漿料。熱起始劑··環氧樹脂：塑化 劑之重量比為1 : 1: 0.1。將漿料放置真空烘箱中脫泡及去 除MEK溶劑至適當的固含量及黏度，然後將塗料精密連 續塗佈機塗佈至Arton基板上經烘箱硬化後可得成捲之產 品。 將實施例所形成之光學膜與商品TAC膜經 K0BRA-21ADH 雙折射分析儀（Optical birefringence 0954-A21972TWF(N2)；P54950097TW；esm〇nd 14 200827787BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultra-low hysteresis optical film and the use of the optical film in a polarizer protective film. [Prior Art] Liquid helium, and LCDs have been widely used in personal computer monitors, digital cameras, and mobile phones, as well as large-sized TVs. In LCD panels, polarizers are the basic components of liquid crystal displays. The lack of (10) Μ·) is a light plate that only allows light in a certain direction to pass through. In the process of making a liquid crystal panel, it is necessary to use the film one by one, and insert it in a staggered direction. The main purpose = in presence, field and When there is no electric field, the light source is phase-difference and shows a state of light and dark to display subtitles or patterns. As the amount of lcd increases, the demand for polarizing plates increases. The polarization of the polarizing film is contained in a transparent polymer film. The directional light is caused by a non-isotropic absorber. For example, a polarizing plate of polyvinyl alcohol adsorbs iodine or a dichroic dye in a polyvinyl alcohol oxime, and the stalk extends to have a uniaxial directivity. The expansion of the range of use of LCD products has become more and more demanding on the hot and humid working conditions of polarized products. Polarizers made of such materials are easily encountered in the heat and humidity reliability test. The optical characteristic deterioration U is due to the fact that (4) the molecular structure is easily destroyed under the conditions of high temperature and high humidity, so the polarizing film needs the S double-sided protective film as the support and protection for the purpose of (4) long-term and mechanical strength. Triacetate (TAC). This: characteristics must have high silk rate, low birefringence, excellent (four) heat, cold \ light, 0954-A21972TWF (N2); P5495 〇〇 97TW; esm〇nd 200827787 moisture resistance Uniformity of force and optics, that is to say, no foreign matter or visible markings. The solvent-coated cellulose triacetate protective film is easy to adhere to the polarizing film because of its transparency, appearance and adhesion. It has been used up to now. Due to the increasing popularity of large-size LCD TVs, TAC protective films have been required to have lower birefringence properties. Currently, TAC has a small R-value (in-plane-retardation), but Rtli is still large (out-of- Plane retardation. This Rth value will result in imperfect optical compensation effects on the LCDs (eg black and white contrast drops and color changes (c〇1〇rshift) at large angles. • The problem occurs. So her value needs to be more Small is better, especially IPSOn-plane switching^ mode LCD. Usually, the polymer has its own birefringence, and its value increases as the molecular chain orientation in the polymer increases, and the Rth value is difficult to reduce due to the polymer. Molecular chains tend to be aligned in-plane. Therefore, in order to reduce birefringence, a compensation method is generally used, for example, a polymer of zero birefringence (zero 折射 bi birefringenee) has recently been developed in Japan ( W02006098517; JP2006096793), which compensates for the positive birefringence of a polymer by using a negative birefringent inorganic crystal or an additive to prepare a polymerization mixture of zero birefringence. There are also low-birefringent cycloolefin polymers (JP2006124628; US2004099973; JP2004168063). When the main chain and branches are used to protect the PVA polarizer film, the wall is difficult to hydrophilic. On the PVA. SUMMARY OF THE INVENTION A primary object of the present invention is to provide an ultra-low hysteresis optical film to improve the optical compensation effect of a liquid crystal display at a large angle. For the above and other purposes, the ultra-low hysteresis optical film of the present invention is mainly 0854-A2t972TWF(N2); P54950097TW; esmond 6 200827787 includes a light-transmitting resin having a three-dimensional interchain structure; and, a nano-scale The metal oxide particles are dispersed in the light-transmissive resin; wherein, the in-plane optical hysteresis (R〇; in_plane retardati〇n) of the optical film is outside the plane of the 〇~2 nm light hysteresis (Rth; 〇ut-of_plane The retardation value is close to Onm. The present invention further provides a polarizing plate, which mainly comprises a polarizer, and the ultra-low hysteresis optical film is disposed on at least one surface of the polarizer as a polarizer protective film. • [Embodiment] The main component of the ultra-low hysteresis optical film of the present invention is a high light-transmissive resin and a mixture of nano-sized metal oxide particles uniformly dispersed on the surface and inside of the light-transmitting resin layer, and It is called a nano composite. As shown in Fig. 1, the ultra-low hysteresis optical film 10 of the present invention is a composite material whose composition includes a light-transmitting resin 10a and a nano-sized metal oxide particle 10b uniformly dispersed in a resin. The light-transmitting resin l〇a Φ used in the present invention has a structure of three-dimensional interlinking after being reacted and solidified, so that the molecular chain has almost 70 full thermal directivity, that is, it has optical directionality, so it is excellent in zero. Birefringent transparent material. Further, the uniform distribution of the nano-sized particles 1〇1) in the light-transmitting resin 10a in addition to the optical equi-directionality itself can also disturb the directivity of the molecular chain, thereby increasing the optical isotropicity. On the other hand, the incorporation of the nano-sized particles l〇b can improve the hardness, the thermal dimensional stability, the hydrophilicity, and the moisture permeability. The light-transmitting resin used in the present invention has a light transmittance of 90% or more, mainly epoxy resin or acrylate resin, and suitable epoxy resin includes 0854-A21972TWF(N2); P54950097TW; esmond 7 200827787 epoxy group ( Oxirane dng) a monomer, oligomer, or polymer. Preferred specific examples include: bisphen A 1 ep〇xy resin, bismuth F ep〇Xy resin, and bismuth epoxide Bisphenol S epoxy resin, phenolic N〇v〇lak epoxy resin, Novolak epoxy resin, alicyclic epoxy resin, or nitrogen- or hydrogenated naphthalene epoxy resin, bisphenol S-ring Oxygen resin and biphenyl type epoxy resin and the like. These epoxy resins can be used singly or in combination, depending on the processing and physical properties required. The acrylate resin used includes monomers, oligomers or polymers thereof, and preferred specific examples include: epoxy acrylate, polyamino phthalate acrylate, polyester acrylate, hydrazine, 6-hexadiol Diacrylate (HDDA), hydroxyethyl methacrylate (hema) and the like. These same acrylate resins can be used singly or in combination, even in combination with the above-mentioned epoxy resins, and can be appropriately selected and formulated depending on the desired processing and physical properties. The light-transmitting resin of the present invention further comprises a hardener which can be classified into two types, a thermal initiator and an ultraviolet light initiator, both of which can be used alone or in a mixed manner in the present invention. For epoxy resin systems, the hot starter may be selected from an acid anhydride and a partially esterified anhydride type hardener such as hexahydrophthalic anhydride (HHPA) or tetrahydrophthalic acid. Tetrahydrophthalic anhydride (THPA), methyl tetrahydrophthalic anhydride (MTHPA), methyl hexahydrophthalic anhydride (MHHPA); triethylenediamine; imidazole compound, Such as 2-ethyl-4-mercapto-salt, 2-indolyl sulphate; sarcophagus compound, such as triphenyl stone dance 0954-A21972TWF (N2); R54950097TW; esmond 8 200827787 (triphenylphosphine), tetraphenylboronic acid Tetraphenylphosphonium tetraphenylborate, o-diethylphosphoroditliioate; quaternary salt. The ultraviolet initiator may be selected from a cationic metal compound such as triarylsulfur hexafluoroantimonate (^1^^1811111111011111111116 fork&^1101'03111;1111011), triarylsulfide hexaphosphate (triarylsulphonium hexafluorophosphate), diaryliodonium salt, and the like. For the acrylate resin system, the ultraviolet initiator may be selected from a radical type photoinitiator such as a ketone series, a phosphine series, an indonium salt or the like. UV hardener··Epoxy/Acrylate The weight of the resin is better between 〇·〇3: 0.15, more preferably between 〇.〇5: 0.1. Thermal hardener: The weight of the epoxy resin/acrylate resin is better between 〇·6: 1.3' more preferably between 〇·9: I]. The transparent resin of the present invention may be added with other conventionally used additives as needed, for example, a plasticizer may be added to increase the processability of the transparent resin, and to extend the life and use thereof, and the addition amount thereof is generally 1 〇 5 〇 phr (per One hundred resin) between. Compared with the traditional molecular structure of cellulose triacetate (TAC), the molecular structure of the resin system of the present invention is a three-dimensional interlaced structure after the reaction. Therefore, the molecular chain is almost completely non-directional, and optically Isometric - so is an excellent zero birefringence transparent material. Furthermore, the thermal size stability of the crosslinked structure is better, and the glass transition temperature of the hardened material can be obtained between 80 and 190 ° C according to different formulations, so that the thermal dimensional stability can be obtained with good transparency. Optical film material. 〇954-A^72TWF(N2); P5495〇〇97Tw; esm〇nd 200827787 The average particle diameter of the nano metal oxide particles of the present invention is between 1 and 5 nanometers, and more preferably, it is between 5 and 5 nanometers. ~20 nm between. Since the nanoparticle has a particle diameter of less than 50 nm and is uniformly dispersed in the light-transmissive resin layer, the light through the nanocomposite is not scattered and reflected, and can achieve a light transmittance of 9% or more (full light transmittance). . Suitable nano metal oxide particles include, but are not limited to, cerium oxide (Si 〇 2), titanium dioxide (Ti 〇〇, dioxide hammer (Zr 〇 0, alumina (Ai 2 〇 3), zinc oxide (Zn 〇) Magnesium oxide (Mg), etc. The above-mentioned nanoparticles may be used alone or in combination of two or more. Since the thermal expansion coefficient of the nano-oxide particles is low, the nano composite of the present invention The thermal expansion coefficient is lower than that of the conventional thermoplastic optical film. Thus, a transparent optical film having good flatness and thermal dimensional stability can be obtained. In addition, in order to protect the surface of the polarizing plate, a layer is generally applied on the polarizing plate. A hard c〇at layer having a thickness of about 5 to 1 〇μηη, usually made of an epoxy resin or an acrylate resin, and the nano metal oxide particles added by the present invention have a very high hardness characteristic in nature. It can reinforce the weak point of low hardness of the resin, so the hardness of the nano composite material of the invention is much higher than that of the conventional thermoplastic optical film, so that the uniform high hardness in the table can be obtained (pencil Transparent optical film with a degree of more than 3H) and abrasion resistance, without the need for an additional hard layer. In addition, the nano metal oxide particles can increase the hydrophilicity of the material to increase the bonding strength with the polarizer. The content is preferably between 5 and 50% by weight, more preferably between 1 and 3% by weight based on the total weight of the optical film. According to the study by the inventors, as long as the size of the nanoparticles Small enough, its content does not seriously affect the light transmittance, so although generally not required, the nano particles contain 0954-A21972TWF (N2): P54950097TW; esmond 10 200827787 may also exceed 50% by weight. The source of the nano particles may be selected from commercially available solid powder or solution state. In addition to the above components, the optical film of the present invention may also be added with a conventional antioxidant or ultraviolet light absorber to avoid deterioration of the protective film and ensure polarization. The reliability of the board. For example, the ultraviolet light absorber can absorb ultraviolet light with a wavelength below 380 nm. The antioxidant and the ultraviolet light absorber can be added separately or simultaneously, generally The addition amount is about 1-3% by weight (based on the total weight of the optical film). • Figure 2 shows a device that can be used to make the above optical film. It should be noted that the device of the figure is only used For example, the optical film of the present invention is not limited to being formed by such a device. First, all the raw materials are scaled according to the formulation ratio and uniformly mixed into the kneading tank 12 to form a slurry. According to the present invention, the slurry may be none. Solvent (solid content 100%> or solvent-containing system (solid content: 40% by weight or more); preferably, the viscosity of the slurry is between 200 and 6000 cp, in order to facilitate subsequent coating operations. The post-injection coating device 13 (roller or die) is precisely coated on the release carrier film 14 with a set thickness, and the coated release carrier film 14 is driven at a constant speed via the drive roller 15. At a rate of about 0.5 to 10 m/rnin, the coating is hardened and then taken up by the take-up reel 17 by a hardening device 16, such as a hot oven or ultraviolet irradiation zone. The transparent optical protective film formed is as shown in Fig. 18, and its suitable thickness is between 1 〇 and ι 〇〇 μπι, preferably between 20 and 80 μπι, both in terms of physical properties and cost. The release carrier film 14 may be a mirror stainless steel tape or a thermoplastic film such as amino phthalate resin, acrylate resin, polyester resin, polyvinyl alcohol, 0954-A21972TWF (N2): P5495009 丌 W; esmond 11 200827787 ethylene Ethyl alcohol copolymer, vinyl chloride resin, ethylene vapor hydride tree, %: unloaded light copolymer (MCOC) resin, polycarbonate S resin, polyarylate resin, etc. . Fig. 3 is a view showing the application of the ultra low light retardation optical film of the present invention as a polarizer film. As shown in Fig. 3, the polarizing plate 30 includes a polarizer 5 sandwiched between the first protective film 1 (ultra-low light retardation optical film) and the second protective film 2''. The transparent optical protective film of the present invention may be provided on one side or both sides of the polarizer. Therefore, the material of the second protective film 20 in FIG. 3 may be the ultra low light retardation optical film of the present invention, but may also be a conventional protective film such as cellulose ester, polycarbonate, acrylic, polyester, Polyolefin, norbornene, and the like. The polarizer 5 used herein is not particularly limited as long as it has a polarizing property, for example, a polyvinyl alcohol (PVA) or a polyene (P〇lyene) polarizer. The transparent optical protective film 10 of the present invention has a suitable thickness of between 1 〇 and ΙΟΟ μηη, preferably between 20 and 80 μτη, both in terms of physical properties and cost. In addition, an anti-glare film may be further formed on the protective film 1 (eight (7), _ thickness is preferably between about 2 and ΙΟμπι or an anti-reflective film (AR) ll is preferably about 〇·1 to 0·2 μm. The conventional polarizing plate deteriorates the polarizing ability due to insufficient moisture resistance of the protective film, and the transparent optical film of the present invention can improve the optical reliability of the polarizing plate, especially in a high humidity environment. In the preferred embodiment, the protective film of the present invention can achieve a moisture permeability of 60 to 70 g/m 2 /24 hr or less, which is about 1/6 of that of the conventional triacetate protective film. The protective film 10 and 20 can be utilized. A transparent adhesive or a pressure-sensitive adhesive is bonded to the polarizer 5. Further, in order to enhance the subsequent bonding with the polarizer, the strength of the 0954-A2]972TWF (N2); P54950097TW; esmoncl 12 200827787 can be preliminarily surface-treated. Such as plasma, corona, primer (such as pu primer), due to the structure and composition of the composite, after treatment with plasma, corona, etc., its surface has good hydrophilicity, its water contact The angle can be less than 15. This can be enhanced with the essence The bonding between the water-based polarizers is followed by the strength. The polarizing plate of the present invention can be used in combination with other optical films in practical applications, such as a reflective film, a semi-transparent film, and a retardation film (1/2 wavelength and 1/4 wavelength). ), a viewing angle compensation film, etc. For example, the polarizing plate of the present invention can be bonded to a reflective film or a semi-transparent film to form a reflective polarizing plate or a transflective polarizing plate; or The retardation film is bonded to form an elliptical or circular polarizing plate; or is attached to a viewing angle compensation film to form a wide-angle polarizing plate; or, it is bonded to a brightness enhancing film. The polarizing plate of the present invention can be applied to various displays. Including, but not limited to, a liquid crystal display, an organic electroluminescent display, a plasma display, etc. For example, as shown in the liquid crystal display 50 of FIG. 4, the polarizing plate 30 of the present invention can be disposed on any surface of the liquid crystal panel 40. Or the opposite side. The liquid crystal type and driving method are not particularly limited, and may be a TN (twisted 歹彳) type liquid crystal, a vertical alignment type liquid crystal, an IPS (transverse electric field switching) liquid crystal, etc. Further, the liquid crystal panel is usually constructed. The diffusion plate, the iridium array, the backlight element, and the like are included, and are not described herein. The ultra-low hysteresis optical film of the present invention has a Ro light hysteresis of 0 to 2 nm (incident angle of -40° to 40°). °), Rth light hysteresis is close to Onm, and the light transmittance is not less than 90% (full light transmittance), so it can be used to replace the traditional polarizing film of cellulose triacetate protective film to improve the liquid crystal display in the large 0954- A21972TWF(N2); P54950097TW; esmond 200827787 There are problems of contrast drop and color change (c〇1〇r shift) of black and white. It can be seen from the above that the hybrid material of the present invention has zero birefringence and high permeability. In addition to the optical properties of light, it also has excellent resistance to cold and heat, moisture, and can be coated by non-solvent method in the process, which has the advantages of optical uniformity, environmental protection and cost economy. The above and other objects, features, and advantages of the present invention will become more apparent and understood. The nanoparticles used in the examples are "'MEK-ST" produced by Nissan Chemical Co., 'a methyl ethyl ketone (MEK) cerium oxide sol' and the oxidizing in the overall material formulation The content of ruthenium is controlled at 15% by weight. [Examples] A hot starter, hexahydrophthalic anhydride (MHHPA), is dissolved in MEK dioxide, and epoxy resin is added. ΕΙ^4221(υηίοη Carbide) and plasticizer Triol (Union Carbide) form a slurry. The thermal initiator · epoxy resin: plasticizer weight ratio is 1: 1: 0.1. The slurry is placed in a vacuum oven Defoaming and removing the MEK solvent to an appropriate solid content and viscosity, and then applying a coating precision continuous coater to the Arton substrate to obtain a roll of the product after oven hardening. The optical film formed by the example and the commercial TAC Membrane via K0BRA-21ADH birefringence analyzer (Optical birefringence 0954-A21972TWF (N2); P54950097TW; esm〇nd 14 200827787
Analyzer made by Oji Scientific Instruments)量測結果如第 5圖所示（位相差vs.入射角）。經計算後商品TAC膜之平均 Rth高達46nm，而本發明之超低光遲滯光學膜的Rth則接 近 0 nm 〇 經量測實施例光學膜之其他性質，包括濕氣滲透率、 透光率、硬度、表面粗糙度、水接觸角等，所得之各項數 據與傳統之TAC膜並列作一比較如下表所示。The measured results are shown in Fig. 5 (phase difference vs. incident angle). After calculation, the average Rth of the commercial TAC film is as high as 46 nm, and the Rth of the ultra-low-light hysteresis optical film of the present invention is close to 0 nm. The other properties of the optical film of the example are measured, including moisture permeability, light transmittance, Hardness, surface roughness, water contact angle, etc., and the obtained data are compared with the conventional TAC film as shown in the following table.
環氧樹脂/二氧化矽 三醋酸纖維素(TAC) 厚度（μηι) 80 80 比重 1.32 1.10 濕氣滲透率（g/m2/24hr) 60-70 〜400 折射率 1.50 1.50 光遲滯Rth(iim) 〜46 透光率（％) 92 92 玻璃轉移溫度Tg(°C) 80-90 60-80 熱膨脹係數（ppin/°C) 80-90 65 〜75 硬度 3H HB 表面粗糙度（人） 5 〜10A <9.4λ 電暈處理後之表面接觸角 14° 35-40° 上表之數據顯示，本發明之複合材光學膜相較於習知 TAC保護膜具有較佳之濕氣抵抗率、硬度、以及表面接觸 角；而其他偏光片保護膜所需要之特性，例如穿透度、光 延滯、表面粗链度等亦不比TAC差。 0954-A21972TWF(N2)；P54950097TW；esmond 15 200827787 雖然本發明已以數個較佳實施例揭露如上，然其並非 用以限定本發明，任何所屬技術領域中具有通常知識者， 在不脫離本發明之精神和範圍内，當可作任意之更動與潤 飾，因此本發明之保護範圍當視後附之申請專利範圍所界 定者為準。 0954-A21972TWF(N2)：P54950097TW；esmond 200827787 【圖式簡單說明】 第1圖繪示本發明超低光遲滯光學膜之結構示意圖。 第2圖繪示一種可用來製作上述光學膜之裝置。 第3圖繪示一種應用上述光學膜之偏光板。 第4圖繪示一種應用上述偏光板之顯示器。 第5圖繪示實施例之光學膜與TAC商品之雙折射性質 量測結果。 • 【主要元件符號說明】 10〜超低光遲滯光學膜 10a〜透光樹脂 1 Ob〜奈米級粒子 12〜混練槽 13〜塗佈裝置 14〜離型膜 0 15〜驅動滾輪 16〜硬化裝置 17〜捲取滾輪 5〜偏光片 11〜抗眩膜或抗反射膜 20〜保護膜 30〜偏光板 40〜液晶面板 50〜液晶顯示器 0954-A21972TWF(N2):P54950097TW；esmondEpoxy Resin / Ceria Triacetate (TAC) Thickness (μηι) 80 80 Specific Gravity 1.32 1.10 Moisture Permeability (g/m2/24hr) 60-70 ～400 Refractive Index 1.50 1.50 Optical Hysteresis Rth(iim) ~ 46 Transmittance (%) 92 92 Glass transfer temperature Tg (°C) 80-90 60-80 Thermal expansion coefficient (ppin/°C) 80-90 65 ～75 Hardness 3H HB Surface roughness (person) 5 ～10A < 9.4λ Surface contact angle after corona treatment 14° 35-40° The data in the above table shows that the composite optical film of the present invention has better moisture resistance, hardness, and surface than the conventional TAC protective film. Contact angle; other polarizer protective film required characteristics, such as penetration, optical retardation, surface thick chain, etc. are not worse than TAC. </ RTI> <RTIgt; </ RTI> <RTIgt In the spirit and scope of the invention, the scope of protection of the invention is defined by the scope of the appended claims. 0954-A21972TWF(N2): P54950097TW; esmond 200827787 BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic view showing the structure of an ultra low light retardation optical film of the present invention. Figure 2 illustrates an apparatus that can be used to fabricate the above optical film. Fig. 3 is a view showing a polarizing plate to which the above optical film is applied. Fig. 4 is a view showing a display using the above polarizing plate. Fig. 5 is a graph showing the measurement results of the birefringence properties of the optical film and the TAC article of the examples. • [Main component symbol description] 10 to ultra low light retardation optical film 10a to light transmissive resin 1 Ob~nano particle 12 to kneading tank 13 to coating device 14 to release film 0 15 to drive roller 16 to hardening device 17 to take-up roller 5 to polarizer 11 to anti-glare film or anti-reflection film 20 to protective film 30 to polarizing plate 40 to liquid crystal panel 50 to liquid crystal display 0954-A21972TWF (N2): P54950097TW; esmond