201009397 六、發明說明： 【發明所屬之技術領域】 本發明係關於適合作爲構成用於液晶顯示器等用途之 背光裝置之構件使用之光控制薄膜及使用其之背光裝置。 【先前技術】 對顯示面板（液晶顯示模組等）由背面照明之背光型顯 φ 示裝置（液晶顯示裝置）係在顯示面板之背面設置背光單元 。對於顯示面板之照射光作爲面光源，進行均一化且爲了 提高液晶顯示裝置之正面亮度，因此使用擴散板、擴散薄 片、稜鏡薄片或亮度提昇薄片（反射型偏光板等）等。又， 液晶顯示裝置中，作爲液晶晶胞之構成構件也使用偏光板 、相位差板或彩色濾光片等。 提案使用螢光放電管（線狀光源、冷陰極管）之背光方 式之一例。例如專利文獻1中揭示具備：管狀光源、將此 φ 管狀光源之光由側面入射，再由平坦反射面反射，照明顯 示單元用之導光構件、配設於前述導光構件與前述顯示單 元之間，且藉由前述管狀光源之光將前述顯示單元均一照 明用之至少1片之異向性光散射薄膜的面光源單元。具備 此面光源單元之異向性光散射薄膜係透明樹脂層層合在異 向性散射層之兩面之層合薄膜所構成。異向性光散射層係 由以樹脂構成之連續相與以平均縱橫比5〜1000分散於此 連續相，且與前述連續相之樹脂之折射率不同的樹脂所構 成之分散相所構成。如此異向性散射層係以丙烯系樹脂與 -5- 201009397 苯乙烯系樹脂之組合、或丙烯系樹脂與聚碳碳酸樹脂之組 合所構成。透明樹脂層係與前述連續相相同之樹脂，玻璃 轉換溫度或熔點爲130〜280 °C之透明樹脂所構成。複數之 異向性光散射薄膜爲光散射之方向性彼此不同的狀態配置 於前述導光構件與前述顯示單元之間。 又，背光裝置中，提昇光擴散性的方法係將塑膠薄片 形成透鏡形狀的方法已爲人知，提案組合這種透鏡形狀與 利用光擴散劑之光擴散功能的方法。例如專利文獻2中揭 示用於直下式光源裝置之擴散板中，調配有光擴散劑之樹 脂板的表面形成稜鏡列所成，該稜鏡列之凸部與凹部均爲 曲面形狀，且凹部曲率半徑小於凸部曲率半徑爲特徵的高 擴散板。又，專利文獻2中記載作爲樹脂板之基材樹脂爲 丙烯酸樹脂、聚碳酸酯樹脂、苯乙烯樹脂、MS樹脂、 MBS樹脂、PE、PET、SAN、脂環丙烯酸樹脂、脂環聚烯 烴樹脂、烯烴·馬來醯亞胺交互共聚物、環乙二烯系聚合 物、非晶聚酯樹脂、非晶氟系樹脂等。 專利文獻3中揭示可將入射光散射於光之進行方向的 光散射薄膜，表示散射角Θ與散射光強度F之關係的散射 特性F(e)中，當薄膜之X軸方向之散射特性爲Fx(e)、Y 軸方向之散射特性爲Fy(e)時，在θ = 4~30°的範圍內，滿 足式：Fy(0)/FX(0)>5的異向性光散射薄膜。此專利文獻3 中也記載連續相爲結晶性烯烴系樹脂所構成，分散相爲非 晶性聚酯系樹脂所構成的薄膜。此外也記載在薄膜表面形 成延伸於薄膜之X軸方向之凹凸部的薄膜。 -6- 201009397 專利文獻1 :特開2002-216521號公報（申請專利範圍） 專利文獻2 :特開2〇〇3-〇16819號公報（申請專利範圍） 專利文獻3 :特開2001-159704號公報（申請專利範圍） 【發明內容】 [發明之槪要] [發明欲解決的課題] φ 但是將專利文獻1之單元用於近年之高亮度化及薄型 化的背光型顯示裝置時，顯示面之亮度的均一化不足，殘 留燈圖像。專利文獻1中雖己記載聚碳酸酯系樹脂與聚丙 烯系樹脂之組合，但是爲記載兩樹脂之詳細內容及具體的 調整方法。因此，此薄膜爲了製作不產生空隙，光散射特 性優異之薄膜時，必須調配相溶化劑，且薄片之調整困難 〇 又，專利文獻2之擴散板係以光擴散劑所構成之分散 Φ 相爲等方性，因此亮度之均一化不足。此外，因擴散板之 耐熱性較低，因此即使不使用導光板，而光源由背面直接 照射之方式（直下型）的裝置等、溫度較高的環境下使用擴 散板時，薄膜會變形，或基質相之熱安定性較低時，因伴 隨延伸之變形，使收縮或分散相之形態產生變化，因此光 擴散特性改變，透過光之亮度無法均一化。 專利文獻3之異向性光散射薄膜係因表面之凹凸部的 形狀微小，因此透鏡效果不足’且顯示面之亮度之均一化 不足，燈圖像殘留。此外，專利文獻3之異向性光散射薄 201009397 膜，耐熱性也低’因此直下型之裝置，其光擴散特性產生 變化’透過光之亮度無法均一化。 本發明之目的係提供無燈圖像（lamp image)，可將背 光型液晶顯示裝置等之面光源裝置形成薄型化且高亮度化 之光控制薄膜及背光裝置。本發明之其他目的係提供即使 在高溫下使用，也可抑制光擴散特性之變化的光控制薄膜 及使用其之背光裝置。 [解決課題的手段] 本發明人等爲了解決上述課題，精心硏究的結果發現 藉由（1)以發揮等方的擴散性之至少二片以上的等方性擴散 層與發揮異向的擴散性之異向性擴散層構成光控制薄膜， 且等方性擴散層之霧度爲70%以上者，可在不發現燈圖像 的狀態’而可將背光型液晶顯示裝置等之面光源裝置形成 薄型化且高亮度化，遂完成本發明。又，藉由（2)含有發揮 異方的光擴散性之異向性擴散層、發揮等方的光擴散性之 Q 等方性擴散層、具備特定構造部之透鏡層，構成光控制薄 膜’該光控制薄膜之等方性擴散層的霧度設定爲60%以上 ，且透鏡層配置於比異向性擴散層更接近光射出面側，遂 完成可產生與上述發明同樣之作用效果的另外發明。 換言之，依據本發明之第1觀點時，可提供一種光控 制薄膜’其特徵係以含有至少二片以上之等方性擴散層與 異向性擴散層所構成，前述等方性擴散層之霧度爲70%以 上。依據本發明之第2觀點時，可提供一種光控制薄膜， -8- 201009397 其特徵係以至少含有透鏡層、等方性擴散層及異向性擴散 層所構成，前述等方性擴散層之霧度爲60%以上，前述透 鏡層爲比前述異向性擴散層更接近配置於光射出面側所成 者。 上述發明中，異向性擴散層可含有以透明樹脂構成之 連續相與具有與此連續相不同折射率，且長軸方向配向於 一方之方向的粒子狀分散相。又，重疊二片以上之等方性 φ 擴散層時的霧度可爲90%以上。透鏡層可具備剖面爲幾何 學形狀之複數之構造物以規則排列的構造部。 依據本發明時，可提供一種背光裝置，其係具備線狀 光源與配置於線狀光源上之上述任一光控制薄膜。此發明 中，異向性擴散層之粒子狀分散相之長軸方向爲與線狀光 源之軸方向成爲平行的狀態，配置光控制薄膜。光控制薄 膜由線狀光源側以異向性擴散層、二片以上之等方性擴散 層之順序配置者。又，光控制薄膜由線狀光源側以異向性 # 擴散層、等方性擴散層、透鏡層之順序配置者。 本說明書中，「薄膜」係指不論厚度，且包含薄片。 「霧度」係指以JIS K7 1 36 : 2000所規定的霧度。 [發明效果] 第1観點之光控制薄膜係藉由發揮等方的擴散性之至 少二片以上的等方性擴散層與發揮異向的擴散性之異向性 擴散層構成光控制薄膜，且等方性擴散層之霧度爲70 %以 上’因此不會產生燈圖像（lamp image)，可實現背光型液 201009397 晶顯示裝置等之背光裝置的薄型化，且高亮度化。 第2觀點之光控制薄膜係藉由至少透鏡層、等方性擴 散層及異向性擴散層所構成，該光控制薄膜之等方性擴散 層之霧度爲60%以上，且透鏡層比異向性擴散層更接近配 置於光射出面側，因此不會產生燈圖像（lamp image)，可 實現背光型液晶顯示裝置等之背光裝置的薄型化，且高亮 度化。 又，本發明之光控制薄膜，其本身可抑制燈圖像 (lamp image)顯現，因此用於背光裝置時，可省略以往必 須之擴散板本身。又，依據第1観點之光控制薄膜時，也 可提高正面方向的亮度，因此可省略將光集光用之稜鏡薄 片。依據使用本發明之光控制薄膜的背光裝置時，相較於 以往的背光裝置，可達成薄型化、降低原材料費、組裝加 工成本減縮等，不僅可大幅降低成本，且有助於提昇顯示 體的亮度。 [實施發明之最佳形態] 《光控制薄膜》 首先，說明本發明之一實施形態的光控制薄膜。 第1觀點之光控制薄膜係以含有至少二片以上之等方 性擴散層與異向性擴散層所構成所成，且等方性擴散層之 霧度爲70%以上者。第2觀點之光控制薄膜係以至少由透 鏡層、等方性擴散層及異向性擴散層所構成所成者，前述 光控制薄膜之等方性擴散層之霧度爲60%以上，透鏡層爲 201009397 比前述異向性擴散層更接近配置於光射出面側所成者。 以下無特別聲明時係使用本發明之第1觀點與第2觀 點之兩者。 《異向性擴散層》 首先說明異向性擴散層。異向性擴散層係含有以透明 樹脂構成之連續相與具有與此連續相不同折射率，且長軸 φ 方向配向於一方之方向的粒子狀分散相所構成。 構成連續相之透明樹脂包含熱可塑性樹脂（烯烴系樹 脂、環狀烯烴系樹脂、含鹵素樹脂（包括氟系樹脂）、乙烯 醇系樹脂、乙烯酯系樹脂、乙烯醚系樹脂、（甲基）丙烯酸 系樹脂、苯乙烯系樹脂、聚酯系樹脂、聚醯胺系樹脂、聚 碳酸酯系樹脂、熱可塑性聚胺基甲酸酯樹脂、聚砸系樹脂 (聚醚颯、聚颯等）、聚苯醚系樹脂（2,6-二甲酚之聚合物等） 、纖維素衍生物（纖維素酯類、纖維素胺基甲酸酯類、纖 # 維素醚類等）、聚矽氧樹脂（聚二甲基矽氧烷、聚甲基苯基 矽氧烷等）、橡膠或彈性體（聚丁二烯、聚異戊二烯等之二 烯系橡膠、苯乙烯-丁二烯共聚物、丙烯腈-丁二烯共聚物 、丙烯酸橡膠、胺基甲酸酯橡膠、聚矽氧橡膠等）等）、及 熱硬化性樹脂（環氧樹脂、不飽和聚酯樹脂、二烯丙基苯 二甲酸酯樹脂、聚矽氧樹脂等）等。這些透明樹脂可單獨 使用或組合兩種以上使用。這些透明樹脂中，較佳爲聚碳 酸酯系樹脂。 聚碳酸酯系樹脂包含以雙酚類爲基礎之芳香族聚碳酸 -11 - 201009397 酯等。雙酚類例如有二羥基聯苯等之雙酚類；雙酚A、雙 酚F、雙酚AD等之雙（羥芳基）烷類；雙（羥苯基）環己烷等 之雙（羥芳基）環烷類；4-4'-二（羥苯基）醚等之二（羥苯基） 醚類；4-4’-二（羥苯基）酮等之二（羥苯基）酮類；雙酚S等 之二（羥苯基）亞颯類；雙（羥苯基）楓類；9_9_雙（4_羥苯基） 蒔等之雙酚蒔類等。此等雙酚類可爲C2-4環氧院加成物。 此等雙酚類可單獨使用或組合二種以上而使用。 聚碳酸酯系樹脂可爲將二羧酸成分（脂肪族、脂環族 或芳香族二羧酸或其酸鹵化物等）進行共聚的聚酯碳酸酯 系樹脂。此等聚碳酸酯系樹脂可單獨使用或組合二種以上 而使用。較佳之聚碳酸酯系樹脂係以雙（羥苯基）-6烷類 作爲基礎的樹脂，例如雙酚A型聚碳酸酯系樹脂。 聚碳酸酯系樹脂之數平均分子量可選自10000〜50000(例 如 1 5000~30000)的範圍，例如爲 12500〜30000(例如 15000〜25000)，較佳爲 17000~25000(例如 18000-22000)。 若聚碳酸酯系樹脂之分子量過小時，薄膜之強度會降低， 若分子量過大時，熔融流動性與分散相之均勻分散性容易 降低。若組合前述聚碳酸酯系樹脂與特定之聚丙烯系樹脂 時，即使不使用相溶化劑，也不會發生空隙，可形成縱橫 比較高的分散相。 聚碳酸酯系樹脂之熔融流動速率（MFR)係依據 IS01 1 33(300°C、1.2kg 荷重（11.8N))，可選自例如約 3~30g/10分鐘（例如，4~20g/10分鐘）的範圍，通常爲約 5〜30gM0分鐘（例如，5~15g/10分鐘），較佳爲6〜25g/10分 201009397 鐘（例如，7~2〇g/l〇分鐘）’更佳爲8~15g/10分鐘（例如， 9〜12g/10分鐘）。 聚碳酸酯系樹脂之熔點或玻璃轉化溫度’例如爲 130〜280°C，較佳約爲 140~270°C，更佳爲 150〜260°C。 如此聚碳酸酯系樹脂係於製品目錄中，大多被分類成 「中黏度品」、「低黏度品」、「高流動」等級。 分散相也在與前述連續相同樣之透明樹脂中，可單獨 φ 使用或組合二種以上使用與構成前述連續相之樹脂不同折 射率之樹脂。此等透明樹脂中，形成分散相之透明樹脂， 較佳爲聚丙烯系樹脂。 聚丙烯系樹脂含有聚丙烯（均聚物）、丙烯與共聚性單 體之共聚物。共聚性單體例如有烯烴類（乙烯外，還有丁 烯、戊烯、庚烯、己烯等之a-C4-1Q烯烴等）、（甲基）丙烯 酸系單體（例如（甲基）丙烯酸、（甲基）丙烯酸烷酯、（ 甲基）丙烯酸羥烷酯、（甲基）丙烯酸縮水甘油酯等）、脂肪 • 族乙烯酯類（乙酸乙烯酯等）、二烯類等。此等共聚性單體 可單獨使用或組合二種以上使用。此等共聚性單體中，大 多使用a-烯烴類（乙烯、丁烯等）。 丙烯系共聚物中’丙烯含量爲80莫耳％以上（soy 00 莫耳％) ’較佳爲85莫耳％以上，更佳爲90莫耳％以上。 丙烯系共聚物也可爲嵌段共聚物等，通常大多爲無規共聚 物。 較佳之聚丙烯系樹脂爲聚丙烯均聚物、丙烯_乙嫌共 聚物、丙烯·丁烯共聚物、丙烯-乙烯-丁烯共聚物等。聚丙 -13- 201009397 烯系聚合物大多使用聚丙烯均聚物、丙烯-乙烯共聚物。 聚丙烯系樹脂可爲使用齊格勒（Ziegler)觸媒等之聚合 物，較佳爲使用二茂（metallocene)觸媒之二茂觸媒系樹脂 。前述二茂觸媒系樹脂係具有分子量分布較狹窄、低分子 量成分及低結晶成分少的特色。也許因此，即使不使用相 溶化劑，也能夠使聚丙烯系樹脂相（分散相）均勻分散於聚 碳酸酯系樹脂之基質相中。 凝膠滲透層析儀（GPC)中，聚丙烯系樹脂之分子量分 _ 布，例如，重量平均分子量Mw/數平均分子量Mn=l〜2.5( 例如1.2-2.3)，較佳爲1.3〜2(例如1.5〜1.8)，通常可爲 1.3~2.5(例如1 .5〜2.0)。聚丙烯系樹脂之重量平均分子量 Mw，例如爲 lxlO4 〜ΙΟΟχΙΟ4，較佳爲 2χ104~75χ104(例如 3 χ104~50χ104)，更佳爲 3xl04〜3〇χ104。又，GPC 中，分子 量10000以下之低分子量成分的含量，例如爲1體積％以 下，較佳爲0.5體積％以下，更佳爲0.3體積％以下。藉由 GPC之分子量及分子量分布係使用裝置：Waters Alliance Q GPCV-2000、柱：PL2(^m MIXED-A、檢測器：RI、溶媒 :〇-二氯苯，可以溫度：135 °C測定。上述分子量及分子 量分布係使用單分散聚苯乙烯作爲基準物質，並以汎用校 正曲線法校正之聚丙烯換算的値。 聚丙烯系樹脂之MFR係例如依據JIS K72 1 0(230°C、 2_16kg 荷重（21_2N))，例如 3~20g/10 分鐘，較佳爲 4~15g/10分鐘，更佳爲5~10g/10分鐘。 聚丙烯系樹脂可爲結晶性，結晶性聚丙烯系樹脂之結 14- 201009397 晶化度例如爲 Μ-80%，較佳爲20〜7〇°/。’更佳爲30〜60% 。聚丙烯系樹脂之熔點（以示差掃描熱量計DSC之熔解波 峰溫度）例如爲l〇〇~HO°C，較佳爲ll〇~135°C，更佳爲 1 15〜130°C (例如 120〜130°C )。 聚丙烯系樹脂較佳爲使用共聚物（丙烯-乙烯無規共聚 物等）或使用二茂觸媒的二茂系樹脂’特佳爲二茂系共聚 物。 組合此種聚丙烯系樹脂與前述聚碳酸酯系樹脂時，如 上述，實質上即使不含相溶化劑，也不會發生空隙可形成 分散相（具有所定縱橫比之分散相等）。 構成分散相之樹脂（例如聚丙烯系樹脂）與構成連續相 之樹脂（例如聚碳酸酯系樹脂）之熔點或玻璃轉化溫度之差 ，例如爲10〜200°c，較佳爲30~150°C，更隹爲50~120°c 〇 構成連續相之樹脂（例如聚碳酸酯系樹脂）之前述MFR 與構成分散相之樹脂（例如聚丙烯系樹脂）之前述MFR的比 例係前者/後者=〇_8/1〜2.5/1(例如 0.9/1〜2.3/1)，較佳爲 1/1~2/1，更佳爲 1.2/1〜1.7/1。 爲了賦予光擴散性，因此連續相與分散相係以彼此不 同折射率之成分所構成。連續相（例如聚碳酸酯系樹脂）與 分散相（例如聚丙烯系樹脂）之折射率之差，例如爲0.001 以上（例如0.001〜0.3)，較佳爲0·01〜0.3，更佳爲0.01〜0.1 〇 異向性擴散層中，連續相與分散相之比例係配合樹脂 -15- 201009397 之種類或熔融黏度、光擴散性等，可選自例如前者/後者（ 重量比）= 99/1〜3 0/70(例如95/5-40/60)左右的範圍，例如 爲 99/1~5 0/50(例如 95/5~50/5 0)，較佳爲 99/1 〜75/25 (例如 93/7〜70/30)，更佳爲 95/5-60/40，特佳爲 90/1 0〜75/25。 若組合前述聚碳酸酯系樹脂與聚丙烯系樹脂時，不僅 具有實用之熱安定性，且於單軸拉伸溫度等之配向處理溫 度下，分散相容易變形，可得到透過光異向性擴散的薄膜 。而且，經由在擠出成形步驟中之牽伸比或單軸拉伸等之 配向處理，能夠控制分散相粒子之縱橫比，也可容易形成 縱橫比較大的分散相。再者，由於連續相以聚碳酸酯系樹 脂所構成，因此可提高耐熱性或抗結塊性。 又，以聚碳酸酯系樹脂構成基質相（連續相），以聚丙 烯系樹脂構成分散相，可得到耐熱性高，即使在高溫下使 用，也可抑制長期間之光擴散特性的變化。 異向性擴散層在必要時，可含有相溶化劑。使用相溶 化劑時，能夠提高連續相與分散相之混合性與親和性，即 使將薄膜進行配向處理，也可防止缺陷（空隙等之缺陷）之 生成，故能夠防止薄膜之透明性降低。再者，能夠提高連 續相與分散相之黏著性，即使將薄膜進行單軸拉伸，也能 夠降低分散相附著於拉伸裝置。 相溶化劑例如有雙噁唑啉化合物、改性基（羧基、酸 酐基、環氧基、噁唑啉基等）所改性之改性烯烴系樹脂、 含有二烯或橡膠之聚合物（例如，經由丁二烯、異戊二烯 等之二烯系單體之均聚物、或二烯系單體與共聚性單體（ -16- 201009397 苯乙烯等之芳香族乙烯單體等）之共聚合所得的二烯系共 聚物（無規共聚物等）；丙烯腈-丁二烯苯乙烯共聚物（ABS 樹脂）等之二烯系接枝共聚物；苯乙烯-丁二烯（SB)嵌段共 聚物、氫化苯乙烯-丁二烯（SB)_嵌段共聚物、氫化苯乙烯_ 丁二烯-苯乙烯嵌段共聚物（SEBS)、氫化（苯乙烯-乙烯/ 丁 烯-苯乙烯）嵌段共聚物等之二烯系嵌段共聚物或此等之氫 化物等）、以前述改性基（環氧基等）改性之含有二烯或橡膠 φ 之聚合物（前述嵌段共聚物等）等。此等相溶化劑可以單獨 使用或組合二種以上使用。 前述二烯系單體例如有共軛二烯可列舉丁二烯、異戊 二烯、1，3-戊二烯、2,3-二甲基-1，3-丁二烯、戊二烯（1,3-戊二烯）、3-丁基-1，3-辛二烯、苯基-1,3-丁二烯等可具有 取代基之C4.2Q共軛二烯。共軛二烯可單獨使用或組合二 種以上使用。此等共軛二烯中，較佳爲丁二烯、異戊二烯 。前述芳香族乙烯單體例如有苯乙烯、（X-甲基苯乙烯、乙 • 烯基甲苯（對甲基苯乙烯等）、對第三丁基苯乙烯、二乙烯 基苯類等。此等芳香族乙烯基單體中，較佳爲苯乙烯。此 等單體可單獨使用或組合二種以上使用。 改性係將與改性基對應之單體（例如，羧基改性係（甲 基）丙烯酸等含羧基之單體、酸酐基改性係馬來酸酐、酯 基改性係（甲基）丙烯酸系單體、馬來醯亞胺基改性係馬來 醯亞胺系單體、環氧改性係（甲基）丙烯酸縮水甘油酸酯等 之含環氧基的單體）藉由共聚來進行。另外，環氧改性也 可藉由不飽和雙鍵之環氧化來進行。 -17- 201009397 相溶化劑通常使用具有與聚合物摻合系之構造樹脂相 同或共通成分之聚合物（無規、嵌段或接枝共聚物）、相對 於聚合物摻合系之構造樹脂爲具有親和性的聚合物（無規 、嵌段或接枝共聚物）等。 較佳之相溶化劑係末改性或改性之二烯系共聚物，特 別是改性嵌段共聚物（例如，已被環氧化之苯乙烯-丁二烯· 苯乙烯（SBS)嵌段共聚物等之環氧化二烯系嵌段共聚物或 環氧改性二烯系嵌段共聚物）。環氧化二烯系嵌段共聚物 不僅透明性高，且軟化溫度也較高約爲7(TC，連續相（例 如聚碳酸酯系樹脂）與分散相（例如聚丙烯系樹脂）之多種組 合中’使樹脂相溶化，可使分散相均勻分散。 前述嵌段共聚物係例如可以共軛二烯嵌段或其部分氫 化嵌段與芳香族乙烯嵌段來構成。環氧化二烯系嵌段共聚 物中’前述共軛二烯之雙鍵的部分或全部被環氧化。芳香 族乙烯嵌段與共軛二烯嵌段（或其氫化嵌段）之比例（重量比 )係例如前者/後者=5/95~80/20左右（例如，約爲25/75〜80/20) ’更佳約爲10/90〜70/30(例如，約爲30/70~70/30)，通常約 爲 50/50〜80/20 。 嵌段共聚物之數平均分子量可選自例如5,000〜1，000,000程 度，較佳爲7,000〜900,000程度，更佳爲10,000〜800,000程度 的範圍。分子量分布[重量平均分子量（Mw)與數平均分子 量（Μη)之比（Mw/Mn)]，例如爲10以下（1~10程度），較佳 爲1〜5程度。 嵌段共聚物之分子構造可爲直線狀、分枝狀、放射狀 -18- 201009397 或此等之組合。嵌段共聚物之嵌段構造例如有單嵌段構造 、星型（teleblock)構造等之多嵌段構造、三鏈徑向星型構 造、四鏈徑向星型構造等。此種嵌段構造係將芳香族二烯 嵌段作爲X、共軛二烯嵌段作爲Y時，例如有χ_γ型、X-Y-X 型、Y-X-Y 型、γ-χ_γ-χ 型、χ_γ.χ_γ 型、χ-γ_χ_γ_ X 型、Υ-Χ-Υ-Χ-Υ 型、（X_Y_)4Si 型、（Y-X_)4Si 型等。 環氧化二烯系嵌段共聚物中之環氧基的比例係無特別 限制，環氧乙烷之氧濃度表示例如0 · 1 ~ 8重量％，較佳爲 0.5〜6重量％ ’更佳爲1~5重量％。環氧化嵌段共聚物之環 氧當量（JIS K 723 6)係例如 300~1 000程度，較佳爲 500〜900程度，更佳爲600~800程度。 相溶化劑（環氧化嵌段共聚物等）之折射率可約略同於 與分散相樹脂（例如與聚丙烯系樹脂之折射率差約爲 0〜0.01，較佳爲0〜0.005，特佳約爲0.001〜0.005)。 前述環氧化嵌段共聚物係將二烯系嵌段共聚物（或部 分已被氫化之嵌段共聚物）藉由慣用之環氧化方法，例如 ，於惰性溶劑中，利用環氧化劑（過氧化物類、過氧化氫 類等），以環氧化的方法可製造前述嵌段共聚物。 相溶化劑之使用量係可選自例如樹脂組成物整體（例 如聚碳酸酯系樹脂及聚丙烯系樹脂之總量）之0.1〜20重量 %，較佳爲0 · 5 ~ 1 5重量％，更佳爲1〜1 0重量％程度的範圍 。如前述，本發明藉由組合特定之前述聚碳酸酯系樹脂與 特定之聚丙烯系樹脂，即使不含有相溶化劑，也可將分散 相均勻分散。即使進行單軸拉伸等之配向處理’也可形成 -19- 201009397 無空隙，透過率高的異向性光擴散層。 較佳之異向性光擴散層中，連續相、分散相及相溶化 劑之比例，例如，如下所示。 (1) 連續相/分散相（重量比）= 99/1〜50/50，較佳爲 97/3 〜60/40，更佳爲 95/5~70/3 0，特佳爲 90/10 〜80/20， (2) 分散相/相溶化劑（重量比）= 100/0〜50/50，較佳爲 99/1 〜70/3 0，更佳爲 98/2~80/20。 本發明藉由組合前述聚碳酸酯系樹脂與前述聚丙烯系 樹脂，即使不含有相溶化劑，也可將分散相均勻分散。 以這種比例使用各成分時，各成分不必預先複合化， 即使直接熔融混攪各成分的顆粒，也能夠均勻分散分散相 ，藉由單軸拉伸等之配向處理可防止空隙發生，可得到透 過率高，具有異向性光擴散層。 更具體而言’例如，使用以前述比例含有作爲連續相 之聚碳酸酯系樹脂與作爲分散相之聚丙烯系樹脂的樹脂組 成物時’複合化容易，僅供給原材料，一方面進行複合化 ，一方面熔融製膜，即使進行單軸拉伸，也能夠形成無空 隙之異向性擴散層。 除了聚丙烯系樹脂外，聚乙烯系樹脂、苯乙烯系樹脂 、芳香族聚酯系樹脂（聚對苯二甲酸烷二酯、聚萘二甲酸 院酯等之聚伸烷基芳酯均聚酯、聚伸烷基芳酯單位之含量 爲80莫耳％以上之共聚酯、液晶性芳香族聚酯等）、聚醯 胺系樹脂（聚醯胺46、聚醯胺6'聚醯胺66等之脂肪族聚 醯胺等）等之聚合物、二氧化矽等之無機粒子也可作爲分 -20- 201009397 散相之成分使用。 異向性擴散層可含有習用之添加劑，例如安定劑（抗 氧化劑、紫外線吸收劑、熱安定劑、光安定劑等）、可塑 劑、抗靜電劑、難燃劑等。 抗氧化劑例如有酚系抗氧化劑、氫醌系抗氧化劑、喹 啉系抗氧化劑、硫系抗氧化劑等。酚系抗氧化劑中，較佳 爲：受阻酚類，例如，2,6-二第三丁基對甲酚、2,2’-亞甲 φ 基雙（4-甲基-6-第三丁基酚）、2,2'-硫代雙（4-甲基-6-第三 丁基酚）等之烷基酚系抗氧化劑；正十八烷基〔3-(3,5-二 第三丁基-4-羥苯基）丙酸酯〕等之C1G-3 5烷基〔3-(3,5-二 第三丁基-4-羥苯基）丙酸酯〕；1，6_己二醇雙〔3-(3,5-二 第三丁基-4-羥苯基）丙酸酯〕等之C2_1()烷二醇雙〔3-(3,5-二第三丁基-4-羥苯基）丙酸酯〕；三乙二醇雙〔3-(3-第三 丁基-5-甲基-4-羥苯基）丙酸酯〕等之羥基C2_4烷二醇雙〔 3-(3,5-二第三丁基-4-羥苯基）丙酸酯〕；甘油三〔3-(3,5-• 二第三丁基-4·羥苯基）丙酸酯〕等之C3_8烷三醇三〔3-(3，5-二第三丁基-4-羥苯基）丙酸酯〕；季戊四醇四〔3-(3,5-二第三丁基-4-羥苯基）丙酸酯〕等之（：4-8烷四醇四〔 3-(3,5-二第三丁基-4-羥苯基）丙酸酯〕；N，N'-伸己基雙 (3,5-二第三丁基-4-羥基氫化肉桂醯胺）等之！<^-(：2-1()伸 烷基雙（3,5-二第三丁基-4-羥基氫化肉桂醯胺）等。 胺系抗氧化劑中，受阻胺類例如包含1,2-雙（2,2,6,6 四甲基-4-哌啶氧）乙烷、苯基萘胺、N，N'-二苯基-1，4-苯二 胺、N-苯基-Ν'-環己基-1，4-苯二胺等。 -21 - 201009397 氫醌系抗氧化劑例如包含2,5-二第三丁基氫醌等；喹 啉系抗氧化劑中，例如包含：6-乙氧基-2,2,4-三甲基-1，2-二羥基喹啉等。另外，硫系抗氧化劑中，例如包含：二月 桂基硫二丙酸酯、二硬脂醯硫二丙酸酯等。 紫外線吸收劑例如有水楊酸苯酯、2,4-二第三丁基苯 基-3，5-二第三丁基-4·羥基苯甲酸酯等之水楊酸酯系紫外 線吸收劑；2-(2-羥基-5-甲基苯基）苯并三唑、2·〔 2-羥基- 3- (3,4,5,6-四氫化鄰苯二甲醢亞胺甲基）-5·甲基苯基〕苯 并三唑、2-〔 3-第三丁基-2-羥基-5-甲基苯基〕-5-氯苯并 三唑、2-(2-羥基-5-第三丁基苯基）苯并三唑、2-(2-羥基-3,5-二第三丁基苯基）苯并三唑、2-(2-羥基-3,5-雙（α,α-二 甲基苄基）苯基）苯并三唑、辛基-3-〔3-第三丁基-4-羥基-(5-氯-2H-苯并三唑-2-基）苯基〕丙酸酯、2-(2H-苯并三唑-2-基）-4,6-雙（l-甲基-l-苯基乙基）酚、2-(2H-苯并三唑-2-基）-6-(1-甲基-1-苯基乙基）-4-(1，1，3,3-四甲基丁基）酚等之 苯并三唑系紫外線吸收劑；2 -羥基二苯甲酮、2 -羥基-4-甲 氧基二苯甲酮、2-羥基-4-辛氧基二苯甲酮、2,2’-二羥基- 4- 甲氧基二苯甲酮等之二苯甲酮系紫外線吸收劑；2_(4,6_ 雙（2,4-二甲基苯基）-1，3,5-三嗪-2-基）-5-羥苯基與環氧乙 烷之反應生成物、2-(2,4_二羥苯基）-4,6-雙（2,4-二甲基苯 基）-1,3,5-三嗪）與2-乙基己基縮水甘油酸酯之反應生成物 、2,4-雙〔2-羥基-4-丁氧苯基〕-6-(2,4-二丁氧苯基）-1，3,5-三嗪等之羥苯基三嗪系紫外線吸收劑等。 光安定劑（HALS)例如具有2,2,6,6-四甲基哌啶骨架、 201009397 1,2,2,6,6-五甲基-4-哌啶骨架之化合物，例如， Ν，Ν·,Ν"，Ν·"-四（4,6-雙（丁基-(N-甲基-2,2,6,6-四甲基哌啶-4-基）胺基）三嗪-2-基）-4,7-二氮雜癸烷-l，l〇-二胺、癸烷二酸 雙（2,2,6,6-四甲基-1-辛氧基-4-哌啶氧基）酯、雙（1，2,2,6,6-五甲基-4-哌啶基）〔〔3,5-雙（1,1-二甲基乙基）-4-羥苯基〕 甲基〕丁基丙二酸酯、雙（1，2,2,6,6-五甲基-4-哌啶基）癸二 酸酯、對應於此等二羧酸酯之C4_2Q烷二羧酸酯（丙二酸、 己二酸等）或芳烴二羧酸酯（鄰苯二甲酸酯等）等。 熱安定劑例如有亞磷酸酯系安定劑（三（2,4-二第三丁 基苯基）亞磷酸酯等之三（分枝烷基苯基）亞磷酸酯、雙（烷 基芳基）季戊四醇二亞磷酸酯等）等之磷系安定劑（或磷酸酯 )、硫系熱安定劑、羥基胺系熱安定劑等。 此等安定劑（例如光安定劑等）可爲低分子量型，也可 爲高分子量型。安定劑可單獨使用或組合二種以上成分之 形態（例如，抗氧化劑與紫外線吸收劑之組合、紫外線吸 收劑與光安定劑之組合、抗氧化劑與紫外線吸收劑與光安 定劑之組合等）來使用。各安定劑之使用量係相對於構成 異向性擴散層之樹脂成分100重量份，爲0.01 ~2.5重量份 ，較佳爲0·03~2重量份（例如0·05~1·5重量份），更佳爲 0.07~1重量份（例如〇·1〜〇·7重量份）的情形較多，通常爲 0.07〜0.5重量份（例如0.1〜0.3重量份）。更具體而言，抗 氧化劑係相對於樹脂成分100重量份，爲0.05~1重量份（ 例如0.08〜0.3重量份），紫外線吸收劑係相對於樹脂成分 1〇〇重量份爲0.1 ~2重量份（例如0.2〜0.7重量份），光安定 -23- 201009397 劑係相對於樹脂成分100重量份爲0.03~0.5重量份（例如 0.05〜0_25重量份）。上述安定劑之總量係相對於樹脂成分 100重量份爲〇.〇5〜3重量份（例如〇·ΐ~2重量份），較佳爲 〇.1~1重量份。倂用複數種之安定劑時，第一安定劑（例如 抗氧化層）與第2安定劑（例如紫外線吸收劑）之比例可選自 前者/後者（重量比）= 95/5〜10/90(例如90/10〜30/70)的範圍 〇 若將組合聚碳酸酯系樹脂與聚丙烯系樹脂之複合系予 以熔融擠出成形或予以複合化時，擠出物之一部分逐漸呈 眼垢狀地堆積於模唇（尤其是鄰接於模唇開口部之壁部）， 此堆積物成長而與從模唇擠出的熔融薄片接觸，形成不均 勻之薄片。因此，無法連續製造均句之薄片與薄膜。此時 ，若含有前述安定劑（例如，抗氧化劑及/或紫外線吸收劑） ，尤其選自抗氧化劑及紫外線吸收劑之至少一種（單獨之 抗氧化劑、單獨之紫外線吸收劑、抗氧化劑及紫外線吸收 劑）時，能夠明顯防止前述堆積物之生成及其成長，可連 續製造均勻之薄片及薄膜。此外，抗氧化劑及/或紫外線 吸收劑，尤其至少抗氧化劑可含於與模唇接觸的異向性擴 散層，將透明樹脂層層合於異向性擴散層時，可含於層合 於異向性擴散層之透明樹脂層，或可含於異向性擴散層及 透明樹脂層。異向性擴散層通常含有於選自抗氧化劑及紫 外線吸收劑之至少一者之情形較多。 異向性擴散層中，分散相之形態係長軸之平均長度L 與短軸之平均長度W之比（平均縱橫比、L/W)爲大於I , 201009397 且分散相之長軸方向配向於其中之一方之方向。分散相可 爲纖維狀。分散相之縱橫比通常大於1(例如2-20000)， 例如 3~20000(例如 5〜15000)，較佳爲 10〜12000(例如 50〜10000)，更佳爲 100〜9000(例如 200〜8000)。特別是爲 了提高異向性時，分散相之縱橫比爲 50〜20000(例如 100~15000)，更佳爲 1000〜10000(例如 3000〜8000)。這種 分散相粒子之縱橫比越大，越能夠提高異向性之光散射性 。這種分散相粒子可爲橄欖球型形狀（旋轉橢圓狀等）、繊 維形狀、正方形狀等。異向性擴散層中，分散相之長軸方 向配向於薄膜之所定方向，即X軸方向（接受方向或機械 方向）形成粒子狀分散相。特別是本發明係藉由調高異向 性擴散層之分散相粒子的縱橫比，可展現高的異方散射性 ，且可將生成之異向性擴散光在稜鏡部有效率且集光於正 面方向，因此即使爲薄肉化後之異向性擴散層，也可提高 亮度之均一性。 分散相之長軸的平均長度L可選自例如0.1 ~2 000 μπι 的範圍，例如 1~1 500μιη，較佳爲 1〜1200μιη(例如 1 ·5~1 ΟΟΟμιη)，特佳爲 2~900μιη(例如 5〜800μιη)，通常爲 100〜ΙΟΟΟμιη(例如300〜800μιη)。又，分散相之短軸的平均 長度W可選自例如0.01〜ΙΟμιη的範圍，例如〇_〇ι〜1μιη， 較佳爲0.02〜0·8μιη，更佳爲0.03〜0.7μίη(特別是0.05〜〇.5μιη) 〇 作爲排列度之分散相粒子的配向係數例如〇 · 3 4以上 (0.34~1)，較佳爲〇.4~1(例如0.5〜1)，更佳爲ojm。分散 -25- 201009397 相粒子之配向係數越高，越能對散射光賦予較高的異向性 。配向係數係依據下述式1計算得到。 [數 1]配向係數=(3<cos20>-1)/2 _._(1) (式1中，Θ係表示粒子狀分散相之長軸與薄膜之X軸間的 角度，（長軸與X軸平行時，θ = ο°)，<c〇s2e>係表示針對 各分散相粒子所計算得到之c〇s20的平均，以下述式2表 示） [數 2] <cos2e>=S n(e).cos20.de “.（2) (式2中，n(0)係表示全分散相粒子中具有角度0之分散 相粒子的比例（重量）） 異向性擴散層可具有擴散光之指向性。亦即，具有指 向性係指於異向性擴散光中，散射較強的方向之中，具有 顯示散射強度爲極大的角度。擴散光具有指向性時，於後 述之圖5之測定裝置中，將擴散光強度F對於擴散角度Θ 進行繪圖時，圖曲線於特定擴散角度Θ之範圍（不含θ = 0° 的角度區域）具有極大或肩部（尤其極大等之反曲點）。將指 向性賦予異向性光擴散薄膜時，分散相粒子之長軸的平均 長度例如爲10〜ΙΟΟμιη，較佳爲20~60μιη。 異向性擴散層的厚度爲3〜500μπι(例如3~300μιη)，較 佳爲 5~200μιη(例如 10~200μιη)，更佳爲 15~150μιη(例如 -26- 201009397 30〜120μιη) 〇 異向性擴散層係可爲使透過光以異方向性產生光擴散 之單層體，或異向性擴散層與層合於其至少一面之透明樹 脂層所構成的層合體所構成。含有異向性擴散層之層合體 可將透明樹脂層層合於異向性擴散層之一面或兩面。 透明樹脂層係透明性高的樹脂，例如包含熱可塑性樹 脂〔烯烴系樹脂、環狀烯烴系樹脂、含鹵素之樹脂（包含 Φ 氟系樹脂）、乙烯醇系樹脂、脂肪酸乙烯酯系樹脂、（甲基） 丙烯酸系樹脂、苯乙烯系樹脂、聚酯系樹脂、聚醯胺系樹 脂、聚碳酸酯系樹脂、熱可塑性聚胺基甲酸酯樹脂、聚碾 系樹脂（聚醚碾礪、聚楓等）、聚苯醚系樹脂（2,6-二甲酚之 聚合物等）、纖維素酯類、矽氧烷樹脂（聚二甲基矽氧烷、 聚甲基苯基矽氧烷等）、彈性體（腈-丁二烯共聚物、丙烯酸 橡膠、胺基甲酸酯橡膠、矽氧烷橡膠等之橡膠熱可塑性彈 性體等）等〕、及熱硬化性樹脂（環氧樹脂、不飽和聚酯樹 • 脂、鄰苯二甲酸二烯丙酯樹脂、矽氧烷樹脂等）等。較佳 之樹脂係熱可塑性樹脂。透明性高的樹脂可爲非結晶性樹 脂。 烯烴系樹脂例如有聚丙烯系樹脂、a-C2_6烯烴與共聚 合性單體之共聚物（乙烯-乙酸乙烯酯共聚物、乙烯-乙烯醇 共聚物、乙烯-(甲基）丙烯酸酯共聚物、乙烯-(甲基）丙烯 酸共聚物或其鹽（例如，離子鍵單體樹脂）等之共聚物。環 狀烯烴系樹脂例如有環狀烯烴（降冰片烯、二環戊二烯等） 之均聚物或共聚物（例如，立體性剛直之三環癸烷等之具 -27- 201009397 有脂環烴基的聚合物等）、前述環狀烯烴與共聚合性單體 之共聚物（乙烯-降冰片烯共聚物、丙烯-降冰片烯共聚物等 )等。此外，構成透明樹脂層之聚丙烯系樹脂係因與構成 前述異向性擴散層之聚丙烯系樹脂的種類、分子量與其分 布、熔融流動速率等而異，但是也可爲同種或至少一部分 之共聚合成分爲共通的同系統（或相同）的樹脂。 含鹵素之樹脂例如有鹵化乙烯系樹脂（聚氯乙烯、聚 氟乙烯等之含鹵素之單體的均聚物、氯乙烯·乙酸乙烯共 聚物、氯乙烯-(甲基）丙烯酸酯共聚物等之含鹵素之單體與 共聚合性單體之共聚物等）、偏鹵化乙烯系樹脂（偏氯乙烯-(甲基）丙烯酸酯共聚物等之含鹵素之偏乙烯基單體與其他 單體的共聚物等）等。 脂肪族乙烯酯系樹脂例如有乙烯酯系單體之均聚物或 共聚物（聚乙酸乙烯酯等）、乙烯酯系單體與共聚合性單體 之共聚物（乙酸乙烯酯-乙烯共聚物、乙酸乙烯酯-氯乙烯共 聚物、乙酸乙烯酯-(甲基）丙烯酸酯共聚物等）或此等之衍 生物。脂肪族乙烯酯系樹脂之衍生物包括聚乙烯醇、乙 烯-乙烯醇共聚物、聚乙烯基縮醛樹脂等。 (甲基）丙烯酸系樹脂可使用（甲基）丙烯酸系單體之均 聚物或共聚物、（甲基）丙烯酸系單體與共聚合性單體之共 聚物。（甲基）丙烯酸系單體例如有（甲基）丙烯酸；（甲基） 丙烯酸甲酯、（甲基）丙烯酸乙酯、（甲基）丙烯酸丁酯、（甲 基）丙烯酸2 ·乙基己酯等之（甲基）丙烯酸C , _ i 〇烷酯；（甲基 )丙烯酸羥烷酯：（甲基）丙烯酸縮水甘油酯；（甲基）丙烯腈 -28- 201009397 :三環癸烷等之具有脂環烴基之（甲基）丙烯酸酚等。共聚 合性單體例如有苯乙烯系單體等。此等單體可單獨使用或 組合二種以上使用。 (甲基）丙烯酸系樹脂例如有聚甲基丙烯酸甲酯等之聚（ 甲基）丙烯酸酯、甲基丙烯酸甲酯·（甲基）丙烯酸共聚物、 甲基丙烯酸甲酯-(甲基）丙烯酸酯共聚物甲基丙烯酸甲酚-丙烯酸酯_(甲基）丙烯酸共聚物、（甲基）丙烯酸甲酯-苯乙 烯共聚物（MS樹脂等）等。較佳之（甲基）丙烯酸系樹脂例如 有以甲基丙烯酸甲酯作爲主要成分（約爲50〜100重量％， 較佳爲70~100重量％)之甲基丙烯酸甲酯系樹脂。 苯乙烯系樹脂例如包含苯乙烯系單體之均聚物或共聚 物（聚苯乙烯、苯乙烯-α-甲基苯乙烯共聚物、苯乙烯-乙烯 基甲苯共聚物等）、苯乙烯系單體與其他聚合性單體（（甲基 )丙烯酸系單體、馬來酸酐、馬來醯亞胺系單體、二烯類 等）之共聚物等。苯乙烯系共聚物例如有苯乙烯-丙烯腈共 聚物（AS樹脂）、苯乙烯與（甲基）丙烯酸系單體之共聚物〔 苯乙烯-甲基丙烯酸甲酯共聚物、苯乙烯-甲基丙烯酸甲酯-(甲基）丙烯酸酯共聚物、苯乙烯-甲基丙烯酸甲酯-(甲基） 丙烯酸共聚物等之苯乙烯-(甲基）丙烯酸酯共聚物〕、苯乙 烯-馬來酸酐共聚物等。較佳之苯乙烯系樹脂包含：聚苯 乙烯、苯乙烯與（甲基）丙烯酸系單體之共聚物〔苯乙烯-甲 基丙烯酸甲酯共聚物等之以苯乙烯與甲基丙烯酸甲酯作爲 主成分之共聚物〕、AS樹脂、苯乙烯-丁二烯嵌段共聚物 等。 -29- 201009397 聚酯系樹脂例如有以芳香族聚酯（聚對苯二甲酸乙二 酯、聚對苯二甲酸丁二酯等之聚對苯二甲酸C2-4烷二酯或 聚萘二甲酸C2.4烷二酯等之均聚酯、芳酸c2_4烷二酯單位 (聚對苯二甲酸c2-4烷二酯及/或聚萘二甲酸c2.4烷二酯單 位）作爲主成分（例如5 0莫耳％以上，較佳爲7 5〜1 0 0莫耳％ ’更佳爲80~100莫耳％)含有的共聚酯等）等。共聚酯例如 包含：C^4烷二醇之一部分以聚氧基C2.4烷二醇、C6_10 烷二醇、脂環二醇（環己烷二甲醇、氫化雙酚A等）、雙酚 A、雙酚A-環氧烷加成物等）等所取代之共聚酯、芳香族 二羧酸之一部份以苯二甲酸、間苯二甲酸酸等之非對稱芳 香族二羧酸、己二酸等之脂肪族C6-12二羧酸等取代之共 聚酯。聚酯系樹脂包含：聚芳香酯系樹脂、使用己二酸等 之脂肪族二羧酸之脂肪族聚酯、ε-己內酯等內酯之均聚物 或共聚物。較佳之聚酯系樹脂通常爲如非結晶性共聚酯（ 例如，芳酸C2-4烷二醇烷酯系共聚酯等）等之非結晶性。 聚醯胺系樹脂例如有聚醯胺6、聚醯胺66、聚醯胺 610、聚醯胺612、聚醯胺11、聚醯胺12等之脂肪族聚醯 胺、二羧酸（例如，對苯二甲酸、間苯二甲酸、己二酸等） 及二胺（例如，已二胺、間二甲苯二胺）之中至少一種成分 爲芳香族化合物之聚醯胺（二甲苯二胺已二酸酯（MXD-6)等 之芳香族聚醯胺等）等。聚醯胺系樹脂可爲ε-己內酯等內 酯之均聚物或共聚物，不限於均聚醯胺，也可爲共聚醯胺 〇 聚碳酸酯系樹脂例如有與上述同樣的樹脂。構成透明 -30- 201009397 樹脂層之聚碳酸酯系樹脂可以與構成前述光擴散層之聚碳 酸酯系樹脂的種類、分子量，熔融流動速率等不同，氮使 使用同種或骨架共通的同系統（或相同）之樹脂時，有時具 有可提高與光擴散層之密著性。聚碳酸酯系樹脂較佳爲以 雙酚A等之雙（羥芳基）Cm烷作爲基礎之聚碳酸酯系樹脂 〇 纖維素酯類例如有脂肪族有機酸酯（二乙酸纖維素酯 、三乙酸纖維素酯等之乙酸纖維素酯；丙酸纖維素酯、丁 酸纖維素酯、乙酸丙酸纖維素酯、乙酸丁酸纖維素酯等之 C! _6有機酸酯等）、芳香族有機酸酯（鄰苯二甲酸纖維素酯 、苯甲酸纖維素酯等之C7_,2芳香族羧酸酯），也可爲乙酸-硝酸纖維素酯等之混合酸酯。 構成透明樹脂層之較佳成分包含烯烴系樹脂、（甲基） 丙烯酸系樹脂，苯乙烯系樹脂、聚酯系樹脂、聚醯胺系樹 脂、聚碳酸酯系樹脂等。較佳之透明樹脂層可以聚碳酸酯 系樹脂構成。構成透明樹脂層之樹脂只要不損害密著性或 機械特性等時，可使用與構成前述異向性擴散層之連續相 及/或分散相之樹脂相同或不同的樹脂，通常較佳爲與連 續相之樹脂相同或共通（或同系統）的樹脂。 構成透明樹脂層之透明樹脂爲了提高耐熱性或耐結塊 性’較佳爲耐熱性樹脂（玻璃轉化溫度或熔點高的樹脂等） 、結晶性樹脂等。構成透明樹脂層之樹脂的玻璃轉化溫度 或熔點約爲130〜280 °C ，較佳爲140〜270 °C ，更佳爲 150 〜260°C ° -31 - 201009397 再者，透明樹脂層可含有習用之添加劑，例如，安定 劑（抗氧化劑、紫外線吸收劑、熱安定劑、光安定劑等）、 可塑劑、抗靜電劑、難燃劑等。尤其是透明樹脂層係以含 有安定劑（抗氧化劑、紫外線吸收劑，光安定劑），較佳爲 選自紫外線吸收劑及光安定劑之至少一種成分（單獨之紫 外線吸收劑、單獨之光安定劑、紫外線吸收劑及光安定劑 )特別是紫外線吸收劑及光安定劑之樹脂層所構成者爲佳 。安定劑可使用與上述相同的成分，相對於構成透明樹脂 層之樹脂成分100重量份之各安定劑的使用量及安定劑的 總量可選自與相對於構成前述異向性擴散層之樹脂成分的 比例相同的範圍。另外，倂用紫外線吸收劑與光安定劑時 ，二者之比例可選自前者/後者（重量比）= 95/5〜5 0/50(例如 90/10~70/3 0)的範圍。 各透明樹脂層之厚度可與前述異向性擴散層相同，例 如，異向性擴散層之厚度約爲3〜3 00 μηι時，透明樹脂層之 厚度可選自3~15μπι。異向性擴散層與各透明樹脂層之厚 度比例，例如異向性擴散層/透明樹脂層=5/9 5〜99/1，較佳 爲30/7 0〜99/1，更佳爲40/60〜95/5。層合薄膜之厚度，例 如 6~600μιη，較佳爲 10~400μιη，更佳爲 20~250μιη° 以往，使用具有數毫米厚度之擴散板，但是本發明不 使用這種厚的擴散板，即使爲數十微米單位之薄片的異向 性擴散層，也能夠有效進行光擴散，可提高顯示裝置之亮 度。特別是即使爲具備管狀光源之背光型液晶顯示裝置， 也能夠有效提高顯示裝置之亮度。 •32- 201009397 異向性擴散層（或異向性擴散層與透明樹脂層之層合 體）依據ns K 73 0 1之全光線透過率係例如50%以上（例如 50~1 00%)，較佳爲60%以上（例如60〜1〇〇%)，特別是可爲 70〜95%(例如75~90%)。此外，異向性擴散層（或異向性擴 散層與透明樹脂層之層合體）的霧度値係8 0%以上（例如 80〜99.9%)，較佳爲90%以上（例如90〜99.8%)，更佳爲 93〜99.5% ’特別是95~99%。全光線透過率較小時，亮度 φ 容易降低’霧度値較小時’光無法均句擴散，使顯示品質 降低。 在異向性擴散層（或異向性擴散層與透明樹脂層之層 合體）的表面，不妨礙光學特性的範圍，可施予電暈放電 處理等的表面處理。 如圖1所示，一例之異向性擴散層1 7以折射率彼此 不同之複數樹脂所構成，可以具有粒子狀分散相17b被分 散於連續層17a中之相分離構造（或海島構造）的單層構造 φ 所形成。 如圖2所示，一例之異向性擴散層28可爲其至少一 面被層合透明樹脂層29的層合構造。含有這種異向性擴 散層28之層合體係以透明樹脂層29保護異向性擴散層28 ’防止分散相粒子脫落或附著，可提高薄膜之耐損傷性或 製造安定性，同時可提高薄膜之強度及使用性。 如圖3所示，一例之異向性擴散層37係以樹脂所構 成之連續相37a及分散於此連續相37a中之異方形狀之分 散相37b所構成。此外，光擴散之異向性係在表示散射角 -33- 201009397 0與散射光強度F之關係之散射特性F(0)中，當薄膜之X 軸方向之散射特性爲Fx(0)，與X軸方向直交之Y軸方向 之散射特性爲Fy(0)時，散射特性Fx(0)及Fy(e)係隨著散 射角Θ成爲廣角度，而顯示光強度漸漸衰減的圖型。又’ 散射角0 =4~30°的範圍內，Fy(0)/Fx(0)之値爲1.01以上， 例如 1.01〜2 00，較佳爲1.1〜150。又，散射角0=18°時， Fy(0)/Fx(0)之値爲 1.1~400(例如 1·1~100)，較佳爲 1.1~200，更佳爲5〜100(特別是10〜80)。 若使用具有這種光學特性之異向性擴散層時，藉由配 置相對於棒狀光源之軸方向，散射於垂直方向，可抑制棒 狀光源本身可辨識的燈圖像，將亮度降低抑制至最小限度 。Fy(e)/Fx(e)之値及散射角0 =18°之Fy(e)/Fx(e)之値太大 時，雖然能夠抑制燈圖像，但是亮度降低情形較大，相反 的，此等値過小時，雖然能夠抑制亮度/之降低，但是會發 現燈圖像。 爲了調製這種散射特性的薄膜時，構成連續相與分散 相之成分（尤其是樹脂）之選擇、成形條件、尤其是擠出溫 度、成形後之牽伸比及冷卻溫度是很重要的，藉由後述種 類及條件製作薄膜，可得到具有這種光擴散特性的薄膜。 此外，異向性擴散層37之X軸方向，通常爲分散相 之長軸方向。因此，將異向性擴散層之X軸方向，相對於 背光單元之線狀光源之軸方向（Y軸方向）成約略平行方向 予以配設。異向性擴散層之X軸方向不一定要完全與背光 單元之線狀光源之軸方向（Y軸方向）平行，例如可在角度土 -34- 201009397 15°(例如±10°，特別是±5°)之範圍内，朝傾斜方向來配設。 散射特性F(e)係使用例如圖4所示裝置來測定。此裝 置係具備：爲了對異向性擴散層37照射雷射光的雷射光 照射裝置（例如，NIHON KAGAKU ENG NE〇-20MS)38、與 測定透過異向性擴散層37之雷射光強度的檢測器39。然 後，以相對於異向性擴散層37之面成90°的角度（垂直）照 射雷射光，藉由相對於散射角β測定（繪圖）經由薄片擴散 之光的強度（散射光強度）F，可求得光散射特性。 異向性擴散層係當光散射之異向性較高時，能夠進一 步減少既定方向之散射角度的依賴性，因此，可更減少亮 度之角度依賴性。前述異向性擴散層係相對於顯示面成垂 直之角度（90°)當做0時，超過相對於顯示面之角度20°， 即使角度40°以上之角度，也能夠抑制亮度之降低。 《等方性擴散層》 φ 其次說明等方性擴散層。等方性擴散層係將光以等方 性產生擴散者。第1觀點係將作爲等方性擴散層之霧度爲 7 0%以上的等方性擴散層使用至少二片以上之光控制薄膜 ，可與異向性擴散層相乘作用達到亮度均勻化，不僅可抑 制燈圖像（lamp image)之產生，也可提高正面亮度。第2 觀點係藉由在光控制薄膜上具備等方性擴散層，可與異向 性擴散層相乘作用達到亮度均勻化，可實現抑制燈圖像 (lamp image)。 等方性擴散層係在表面具有不規則之微細凹凸形狀者 -35- 201009397 ’藉由高分子樹脂與必要時所添加的粒子所構成。可用於 等方性擴散層之高分子樹脂可使用光學透明性優異的樹脂 。例如有聚酯系樹脂、丙烯酸系樹脂、丙烯酸聚胺基甲酸 酯系樹脂、聚酯丙烯酸酯系樹脂、聚胺基甲酸酯丙烯酸酯 系樹脂、環氧基丙烯酸酯系樹脂、胺基甲酸酯系樹脂、環 氧系樹脂、聚碳酸酯系樹脂、纖維素系樹脂、縮醛系樹脂 、聚乙烯系樹脂、聚苯乙烯系樹脂、聚醯胺系樹脂、聚醯 亞胺系樹脂、三聚氰胺系樹脂、酚系樹脂、聚矽氧系樹脂 等的熱可塑性樹脂、熱硬化性樹脂、游離輻射硬化性樹脂 等。這些當中，較佳爲使用耐光性及光學特性優異的丙烯 酸系樹脂。 粒子可使用例如有氧化矽、黏土、滑石、碳酸鈣、硫 酸鈣、硫酸鋇、矽酸鋁、氧化鈦、合成沸石、氧化鋁、蒙 脫石等之無機微粒子、苯乙烯樹脂、胺基甲酸酯樹脂、鳥 糞胺樹脂、聚矽氧樹脂、丙烯酸樹脂等所構成之有機微粒 子。該粒子不僅可使用1種，也可組合複數種使用。 前述粒子對於前述高分子樹脂之含有比例係依據使用 之粒子之平均粒徑或等方性擴散層之厚度而定，無法一槪 而論，若考慮等方向擴散性與亮度之性能平衡時，從後述 之霧度在第2觀點時容易爲6 0%以上，在第1觀點則容易 爲70%以上的觀點，相對於高分子樹脂1〇〇重量份，較佳 爲50重量份以上250重量份以下，更佳爲100重量份以 上250重量份以下。 前述粒子之平均粒徑，若考慮等方向擴散性與亮度之 -36- 201009397 性能平衡時，較佳爲1〜40μπι的範圍内。 等方性光擴散層之厚度係發揮等方向之擴散性，從後 述之霧度在第2觀點時容易爲6 0%以上，在第1觀點則容 易爲70%以上的觀點，較佳爲7〜60μιη，更佳爲20〜35μιη 〇 等方性擴散層中除了上述的高分子樹脂或粒子外，也 可添加光聚合起始劑、光聚合促進劑、平坦劑.消泡劑等 φ 之界面活性劑、氧化防止劑、紫外線吸收劑等的添加劑。 等方性擴散層可爲將該等方性擴散層層合於支持體上 所形成者。支持體可使用以往公知的支持體、例如有玻璃 或塑膠所構成之板或薄膜等。具體而言，可使用聚對苯二 甲酸乙二酯、聚對苯二甲酸丁二酯、聚萘酸乙二酯、聚碳 酸酯、聚丙烯、聚乙烯、聚丙烯酸酯、丙烯酸、以醯基纖 維素、聚偏氯乙烯等之塑膠薄膜或薄片，從尺寸安定性的 觀點，較佳爲經延伸加工、特別是二軸延伸加工者。支持 φ 體之厚度較佳爲10〜400μπι。 第1觀點之等方性擴散層，其霧度爲7 0 %以上，而第 2觀點之等方性擴散層之霧度爲60 %以上。將具備至少2 片以上之霧度爲70%以上之等方性擴散層的光控制薄膜、 或具備霧度爲60%以上之等方性擴散層及後述之透鏡層的 光控制薄膜組裝於背光裝置，不會產生燈圖像（lamp image) ’可實現背光型液晶顯示裝置等之背光裝置之薄型 化且高亮度化。從提高亮度及更有效抑制燈圖像之產生的 觀點，兩觀點之霧度較佳爲8 0%以上，特佳爲90%以上。 -37- 201009397 第1觀點之光控制薄膜係具備至少二片以上之等方性 擴散層所成者，但是重疊二片以上之等方性擴散層時之霧 度較佳爲90%以上，更佳爲95%以上。藉由將重疊二片以 上之等方性擴散層時之霧度設定爲90%以上，當光通過二 片以上之等方性擴散層時，該光在等方性擴散層之内部及 界面時，對正面方向產生折射的成分會增加，具備等方向 的擴散性，可提高對正面方向的亮度。 《透鏡層》 其次說明第2觀點的透鏡層。透鏡層係具備剖面爲幾 何學形狀之複數的構造物所排列的構造部者。前述幾何學 形狀係指例如有三角形狀或多角形狀、台形狀、半圓形狀 等，前述構造物例如有三角錐、角錐、圓錐台、三角柱、 角柱、圓柱、半球形狀等。此外，前述構造物可以複數非 規則性或獨立形成，通常以規則性排列者較佳，例如互相 並列，特別是以相鄰接之形態並列，規則性排列者更佳。 這種透鏡層之較佳的態樣，例如有具備剖面爲三角形 狀之複數的構造物（稜鏡單位）彼此並列，特別是以相鄰接 之形態並列，且規則性排列之構造部的透鏡層，從提高正 面亮度的觀點，更佳。 前述三角形狀可爲不等邊三角形狀，但是較佳爲二等 邊三角形，特別是頂角爲50〜120°(較佳爲60~110°，更佳 爲70~100°)之二等邊三角形狀。剖面中，三角形狀之頂角 係 90°±10°，特佳爲 90°±5°。 -38- 201009397 前述棱鏡單位之間距，可選自例如5~100μηι的範圍， 通常爲10〜80μιη，較佳爲20~60μιη，更佳爲30〜50μηι。 前述稜鏡單位之高度，可選自例如1〜50 μιη的範圍， 通常爲5〜45μπι，較佳爲10〜40μιη(例如15〜30μιη)，更佳爲 1 5〜25 μπι 〇 透鏡層係具備上述的稜鏡部（構造部）者，可爲在成爲 稜鏡部之基底之區域（基底區域）具備稜鏡部者或可爲僅由 Φ 無基底區域之稜鏡部所構成者。基底區域之高度（厚度）例 如爲0〜30μιη(例如 0.1〜30μιη)’較佳爲1〜20μιη，更佳爲 3 〜1 5 μπι 〇 構成透鏡層之材料例如有高分子樹脂。高分子樹脂例 如有熱硬化性樹脂、熱可塑性樹脂、游離輻射硬化型樹脂 等。 熱硬化性樹脂例如有聚矽氧系樹脂、酚系樹脂、尿素 系樹脂、三聚氰胺系樹脂、呋喃系樹脂、不飽和聚酯系樹 • 脂、環氧系樹脂、二烯丙基苯二甲酸酯系樹脂、鳥糞胺系 樹脂、酮系樹脂、胺基醇酸系樹脂'聚胺基甲酸酯系樹脂 、丙烯酸系樹脂、聚碳酸酯系樹脂等。這些可單獨使用， 但是爲了進一步提高交聯性、交聯硬化塗膜之硬度，較佳 爲添佳硬化劑。 硬化劑例如將聚異氰酸酯、胺基樹脂、環氧樹脂、羧 酸等之化合物與適合之樹脂配合使用。 熱可塑性樹脂例如有AB S樹脂、降冰片烯樹脂、聚 矽氧系樹脂、尼龍系樹脂、聚縮醛系樹脂、聚碳酸酯系樹 -39- 201009397 脂、改性聚苯醚樹脂、聚對苯二甲酸丁二醋、聚對苯二甲 酸乙二酯、楓系樹脂、醯亞胺系樹脂、氟系樹脂、苯乙稀 系樹脂、丙烯酸系樹脂、氯乙烯系樹脂、乙酸乙烯系樹脂 、氯乙嫌-乙酸乙稀共聚物系樹脂、聚醋系樹脂、胺基甲 酸酯系樹脂、尼龍系樹脂、橡膠系樹脂、聚乙烯醚、聚乙 儲醇、聚乙燦基丁縮醒、聚乙嫌基耻略院嗣、聚乙二醇等 〇 游離輻射硬化型樹脂可使用例如有藉由游離輻射照射 產生交聯硬化之光聚合性預聚物或光聚合性單體。光聚合 性預聚物特佳爲使用例如1分子中具有2個以上之丙錄酿 基，藉由交聯硬化’成爲3次元網目構造的丙烯酸系預聚 物。此丙烯酸系預聚物例如有聚胺基甲酸酯丙烯酸酯、聚 酯丙烯酸酯、聚環氧丙烯酸酯、三聚氰胺丙烯酸酯、聚氟 烷基丙烯酸酯、聚矽氧丙烯酸酯等，配合模具或基材之種 類、用途等來適當選擇。 此外，光聚合性單體可使用例如2-乙基己基丙烯酸酯 、2-經乙基丙嫌酸醋、2-羥丙基丙儲酸酯、丁氧基乙基丙 烯酸酯等之單官能丙烯酸單體、1，6-己二醇二丙烯酸酯、 新戊二醇二丙烯酸酯、二乙二醇二丙烯酸酯、聚乙二醇二 丙烯酸酯、羥基三甲基乙酸酯新戊二醇二丙烯酸酯等之2 官能丙烯酸單體、二季戊四醇六丙烯酸酯、三甲基丙烷三 丙烯酸酯、季戊四醇三丙烯酸酯等之多官能丙烯酸單體等 之1種或2種以上。 這些光聚合性預聚物或光聚合性單體可分別單獨使用 -40- 201009397 ，但是爲了提高交聯硬化性或賦予黏度調整等各種性能時 ，適當組合使用較佳。 將該功能層以紫外線照射產生硬化來使用時，除了上 述光聚合性預聚物及光聚合性單體外，較佳爲使用光聚合 起始劑或光聚合促進劑等的添加劑。 光聚合起始劑例如有苯乙酮、二苯甲酮、米烯拉酮、 苯偶因、苄基甲基縮酮、苯甲醯苯甲酸酯、α-醯氧基肟 酯、硫雜蒽酮類等。 光聚合促進劑係藉由硬化時空氣中的氧減輕聚合障礙 ，可提高硬化速度者，例如有Ρ -二甲基胺基苯甲酸異戊酯 、Ρ-二甲基胺基苯甲酸乙酯等。 透鏡層可形成於支持體上。支持體可使用與上述等方 性擴散層所列舉者相同者。 對於異向性擴散層之粒子狀分散相之長軸方向，複數 之稜鏡單位的排列方向（或配置方向）無特別限定，例如可 爲對於粒子狀分散相之長軸方向產生交差的方向（直交的 方向、與斜方向交差的方向）。例如粒子狀分散相之長軸 方向與稜鏡單位之排列方向（稜線或長軸方向），例如可在土 15°(較佳爲±10°，更佳爲±5°)的範圍內，實質上可朝相同方 向（實質上並列），例如±15°(較佳爲±10°，更佳爲±5°)的範 圍內，實質上可產生直交（交差）。較佳之樣態係粒子狀分 散相之長軸方向朝稜鏡單位之延伸方向（三角柱狀稜鏡列 之稜線或長軸方向），彼此平行。粒子狀分散相之長軸方 向係與稜鏡單位之延伸方向約略平行時，可提高對正面的 -41 - 201009397 集光效果。此外，粒子狀分散相之長軸方向與稜鏡單位之 延伸方向約略直交時，具有可抑制亮線或暗線的效果。 具備由這種複數之稜鏡單位所構成之構造部的透鏡層 係藉由異向性擴散層，可將異方向擴散之擴散光集光於正 面方向，可使亮度分布平均化。因此，提高正面方向的亮 度，同時可抑制燈圖像（lamp image)之產生’提高顯示品 質。 如圖5所示，第1觀點之一實施形態的光控制薄膜係 具備在兩面形成透明樹脂層49之異向性擴散層47與兩片 在支持體45上所形成之等方性擴散層44。前述異向性擴 散層47係含有以熱可塑性樹脂所形成之連續相（基質）47a 及與此連續相47a之熱可塑性樹脂不同折射率的熱可塑性 樹脂所形成，且配向於前述連續相47a之所定方向，經分 散的粒子狀分散相47b，此外，粒子狀分散相47b係形成 細長狀。換言之，粒子狀分散相4 7b之長軸係配向於異向 性擴散層47之長度方向。此外，此例中’連續相（基質 )47a係以透光性或透明性及耐熱性高的樹脂，例如聚碳酸 酯系樹脂等所形成，粒子狀分散相47b係例如以耐熱性較 高之烯烴系樹脂，例如、聚丙烯系樹脂（使用二茂 (metallocene)觸媒之聚丙烯系樹脂）所形成。又，透明樹脂 層49係以透明性及耐熱性較高之樹脂，例如聚碳酸酯系 樹脂等所形成。 如圖6所示，第1觀點之其他實施形態的光控制薄膜 係不必形成透明樹脂層，具備含有連續相47a與粒子狀分 -42- 201009397 散相47b之異向性擴散層47及兩片等方性擴散層44。 如圖7所示，第2觀點之一實施形態的光控制薄膜係 具備在兩面形成透明樹脂層49之異向性擴散層47、在支 持體45上所形成之等方性擴散層44及透鏡層46。透鏡層 46係具有基底區域。前述異向性擴散層47係含有以熱可 塑性樹脂所形成之連續相（基質）47a及與此連續相47a之 熱可塑性樹脂不同折射率的熱可塑性樹脂所形成，且配向 φ 於前述連續相47a之所定方向，經分散的粒子狀分散相 47b，此外，粒子狀分散相47b係形成細長狀。換言之， 粒子狀分散相47b之長軸係配向於異向性擴散層47之長 度方向。此外，此例中，連續相（基質）47a係以透光性或 透明性及耐熱性高的樹脂，例如聚碳酸酯系樹脂等所形成 ，粒子狀分散相47b係例如以耐熱性較高之烯烴系樹脂， 例如聚丙烯系樹脂（使用二茂（metallocene)觸媒之聚丙烯系 樹脂）所形成。又，透明樹脂層49係以透明性及耐熱性較 φ 高之樹脂，例如聚碳酸酯系樹脂等所形成。透鏡層46係 以複數之剖面三角形狀之稜鏡單位46a所形成。換言之， 各稜鏡單位46a係彼此相鄰接，各稜鏡單位46a之稜線係 沿著前述粒子狀分散相47b的長軸方向延伸，形成稜鏡列 〇 如圖8所示，第2觀點之其他實施形態的光控制薄膜 係不必形成透明樹脂層，具備含有連續相47a與粒子狀分 散相47b之異向性擴散層47、等方性擴散層44及透鏡層 46。此透鏡層46係不具有基底區域。 -43- 201009397 使用這種光控制薄膜時，藉由異向性擴散層，產生異 方向擴散，且藉由等方性擴散層等方向擴散之擴散光集光 於正面方向，降低線狀光源（螢光管等）之正上方的亮度， 可使亮度分布平均化。因此提高正面方向的亮度，同時可 抑制燈圖像（lamp image)之產生，提高顯示品質。 第1觀點之光控制薄膜係藉由至少二片以上之等方性 擴散層與異向性擴散層所構成所成者。藉由具備至少二片 以上之等方性擴散層與異向性擴散層所成，可使由線狀光 源的光經由異向性擴散層產生異方向擴散，使亮度均一化 ，且藉由二片以上之等方性擴散層，使光產生等方向擴散 ，可使亮度更均一化。藉此可調整光的指向性，不會產生 燈圖像（lamp image)，可提高正面亮度。特別是光控制薄 膜以異向性擴散層、二片等方性擴散層的順序所構成，使 等方性擴散層成爲光射出面側的狀態予以配置，更能顯著 抑制燈圖像（丨amp image)之產生，提高正面亮度。 第2觀點之光控制薄膜係至少藉由透鏡層、霧度爲 60%以上的等方性擴散層、異向性擴散層構成所成者，但 是該光控制薄膜之透鏡層係相較於異向性擴散層，配置於 更接近光射出面側者。光控制薄膜之透鏡層爲相較於異向 性擴散層，配置於更接近光射出面側，藉此由線狀光源之 光經由異向性擴散層，產生異方向擴散，可使亮度分布均 一。此外，該異向性擴散層之光射出面側具備透鏡層，因 此藉由該透鏡層使由異向性擴散層出射的擴散光集光於正 面方向。因此可調整光的指向性，不會產生燈圖像（lamp 201009397 image)，可達成高的正面亮度。特別是光控制薄膜以異向 性擴散層、等方性擴散層、透鏡層的順序所構成，使透鏡 層成爲光射出面側的狀態予以配置，更能顯著消除燈圖像 (lamp image)，達成高的正面亮度。 光控制薄膜之異向性擴散層不一定需要形成透明樹脂 層。透明樹脂層不一定要在異向性擴散層之兩面形成，在 異向性擴散層之至少一面形成即可。 φ 光控制薄膜之異向性擴散層與至少二片以上之等方性 擴散層（第1觀點）、或異向性擴散層、等方性擴散層及透 鏡層（第2觀點）可各自密著而構成，但是各層不要密著， 夾雜空隙所構成較佳。各層間存在著空隙時，可有效利用 各層與空隙部分之折射率差，更能消除燈圖像（lamp image)，達成高的正面亮度。 <<構成構件之形成>> 其次說明構成光控制薄膜之構件之形成方法的一例。 首先，異向性擴散層可藉由將構成分散相之成分（樹 脂成分、繊維狀成分等）分散於構成連續相之樹脂中，進 行配向而得。 異向性擴散層之形成方法中，分散相通常係將構成分 散相之樹脂成分變形，予以配向的方法而得。例如將構成 連續相之樹脂（例如聚碳酸酯系樹脂）與構成分散相之成分（ 例如聚丙烯系樹脂）及必要時之相溶化劑等的成分，必要 時藉由常用方法（例如，熔融摻合法、滾筒法等）進行摻合 -45- 201009397 ，再熔融混合，從T模頭或環狀模頭等擠出，進行薄膜成 形，可使分散相分散。另外，可利用將以光散射成分（例 如聚丙烯系樹脂）與黏結劑樹脂（例如聚碳酸酯系樹脂）所構 成的組成物塗佈於基材薄膜上的塗佈法、或層合前述組成 物之層合法、鑄膜法、擠出成形法等習用之薄膜成形法成 形來製造。通常，藉由擠出成形法形成薄膜，調製異向性 擴散層的情形較多。 異向性擴散層之分散相的配向處理可使用例如（1)將擠 出成形薄片拉伸同時製膜的方法、（2)將擠出成形薄片進行 單軸拉伸的方法、（3)組合前述（1)之方法與（2)之方法的方 法等。也可藉由（4)將前述各成分進行溶液摻合，利用鑄膜 法等成膜來形成。 熔融溫度係樹脂成分（連續相樹脂、分散相樹脂）之熔 點以上的溫度，例如 150〜270°C，較佳爲200〜26〇t，更 佳爲 230~255°C。 爲了實現適度的異方向性，在異向性擴散層、熔融製 膜中，將擠出成形薄片拉伸同時製膜較佳。爲了展現所定 之異向性光擴散特性時，調整擠出後之牽伸比是重要的。 牽伸比（牽伸倍率）係配合擠出機之模頭口徑、樹脂之種類 、層構造等，可選自1.5〜50倍的範圍，並非一槪而定， 單層時，例如可選自4〜40倍，較佳爲5~35倍，更佳爲 8〜3 0倍（特別是10~2 5倍）的範圍，前述異向性之參數可選 自前述範圍。層合體時，因有異向性高於單層的傾向，因 此牽伸比例如爲3.5〜20倍，較佳爲4~ 18倍，更佳爲5〜16 201009397 倍（特別是6〜15倍）。 藉由鑄膜輥等之冷卻溫度，例如30〜1 10 °C，較佳爲 40〜100°C，更佳爲60~9(TC程度。異向性擴散層可被延伸（ 一軸或二軸延伸、特別是一軸延伸）。異向性擴散層之延 伸倍率可配合分散相之縱橫比來選擇，例如一方向的延伸 倍率爲1.1〜10倍，較佳爲1.2~5倍，更佳爲1.5〜3倍。 其次，等方性擴散層係在支持體上形成該等方性擴散 φ 層時，例如將上述高分子樹脂或粒子等材料溶解於適當的 溶劑的等方性擴散層用塗佈液，藉由以往公知的方法、例 如棒塗佈機、摻合塗佈機、旋轉塗佈機、輥塗佈機、凹版 塗佈機、流塗佈機、模塗佈機、噴霧機、網版印刷等，塗 佈於支持體上，經由乾燥而形成。 或對於在支持體上所形成之等方性擴散層表面，可進 行例如消光加工·噴沙加工·壓紋加工等，以物理方式粗化 所構成。 參而不使用支持體時，例如將混合高分子樹脂或粒子的 組成物可藉由押出成形機等押出形成，或使用鑄模形成。 其次，第2觀點之透鏡層可使用與所欲得之構造部之 形狀互補的模來形成。例如形成稜鏡部（構造部）時，藉由 鑄模（或模壓）在軟化後之熱硬化性樹脂或熱可塑性樹脂之 基材薄片的表面形成稜鏡部的方法、藉由轉印模將稜鏡部 轉印至透光性基材薄片，必要時將透鏡部予以硬化的方法 、將游離輻射硬化型樹脂塗佈於透光性基材薄片或塗佈時 ，轉動具有與棱鏡單位對應之凹凸部（鄰接之V字狀溝等） -47- 201009397 之輥金屬模，形成稜鏡部，使此透鏡部硬化的方法等來形 成。稜鏡部之基底區域之有無可藉由調整成爲原料之樹脂 組成物之使用量等來控制。 第1觀點之光控制薄膜係藉由至少二片以上之等方性 擴散層及異向性擴散層所構成，等方性擴散層之霧度爲 7 0%以上。因此，組合藉由異向性擴散層之異向性之光擴 散效果與等方性擴散層之等方性光擴散效果，可使亮度高 度均一化。第2觀點之光控制薄膜係由異向性擴散層、等 方性擴散層、及透鏡層所構成者，光控制薄膜之等方性擴 散層之霧度設定爲60%以上，且透鏡層爲相較於異向性擴 散層時，配置於更接近光射出面側者。因此藉由組合異向 性擴散層之異方性的光擴散效果與透鏡層之透鏡效果，可 使亮度高度均一化。 因此，上述光控制薄膜可用於各種光學用途。特別是 可使顯示面之亮度高度均一化，因此即使將背光裝置即形 成薄型化且高亮度化，也可抑制燈圖像之產生。故用於液 晶顯示裝置等之顯示裝置（特別是背光裝置）時，顯示面整 體可均一照明。因此，本發明之光控制薄膜可作爲背光裝 置及顯示裝置（例如液晶顯示裝置等之影像顯示區域爲平 面之面型顯示裝置（平面型顯示裝置））的構成構件使用。 《液晶顯示裝置》 其次說明使用上述光控制薄膜之液晶顯示裝置之一例 -48- 201009397 如圖9及圖1 0所示，一實施形態之液晶顯示裝置係 以具備封入液晶之液晶晶胞之作爲被照射體之面型顯示單 元（透過型液晶顯示單元或液晶顯示面板等）5、配設於此顯 示單元（或面板）5之背面側，照明前述顯示單元5用之背 光單元（本發明之背光裝置）13所構成。 背光單元13係具備在顯示單元5之正下1或並列配 設之複數之螢光放電管（冷陰極管）等的線狀光源1與由線 φ 狀光源1之光向前方方向（顯示單元側）反射，導引至顯示 單元5用的反射板2。 如圖9所示，第1觀點中，線狀光源1之前方必要時 ，可依序配置：配置於線狀光源1之前方的支持板（無圖 示）、位於此支持板之出射面側（背光單元之出光面側），且 將透過光以異方向產生光擴散用之異向性擴散層14、位於 此異向性擴散層14之光射出面側，由異向性擴散層14出 射之光以等方向產生光擴散用之二片等方性擴散層12。由 • 線狀光源1之.光係藉由異向性擴散層14或二片等方性擴 散層12擴散，使亮度均一化，提高亮度照射顯示單元5。 支持板係用於保護薄膜之異向性擴散層14所形成的透明 板。棱鏡薄片雖無圖示，但是也可配合用途配置。 如圖1 〇所示，第2觀點中，線狀光源1之前方必要 時，可依序配置：配置於線狀光源1之前方的支持板（無 圖示）、位於此支持板之出射面側（背光單元之出光面側）’ 且將透過光以異方向產生光擴散用之異向性擴散層14、位 於此異向性擴散層14之光射出面側，由異向性擴散層14 -49- 201009397 出射之光以等方向產生光擴散用之等方性擴散層12、剖面 三角形狀之稜鏡在所定方向並列所形成的稜鏡薄片（透鏡 層）4。由線狀光源1之光係藉由異向性擴散層14或等方 性擴散層12擴散，使亮度均一化，同時藉由稜鏡薄片4 往前方集光，提高亮度照射顯示單元5。支持板係用於保 護薄膜之異向性擴散層14所形成的透明板。 兩觀點均爲面型顯示單元（液晶顯示單元）5係依序層 合第1偏光薄膜6a、第1玻璃基板7a'於此玻璃基板上 所形成之第1電極8a、層合此電極上之第1配向膜9a、 液晶層10、第2配向膜9b、第2電極8b、彩色濾光片11 、第2玻璃基板7b、及第2偏光薄膜6b所形成者。 這種顯示裝置係可藉由内含之螢光放電管（冷陰極管） 等的線狀光源，由背面直接照射面型顯示單元。因此，使 用線狀光源（燈）的背光裝置係隨著近年液晶電視等的液晶 顯示裝置之大型化，液晶顯示裝置中之重要性變得非常高 〇 但是一般由線狀光源之出射光的亮度分布並非均一， 對於線狀光源之軸方向直交之方向的亮度分布不均一。特 別是配置於顯示單元（液晶顯示單元）之正下之線狀光源本 身由顯示面側可看見，而在顯示面有燈圖像（lamp image) 殘留。因此即使用線狀光源，在顯示面之亮度也必須均一 化。特別是異向性擴散層係因接近線狀光源，因此異向性 擴散層被要求長期間安定的光擴散性。 此外，將前述異向性擴散層用於背光單元時，可達到 -50- 201009397 顯示面之亮度均一化，同時可抑制燈圖像（lamP image)之 產生。 第1觀點之光控制薄膜係由至少二片以上之等方性擴 散層與異向性擴散層所構成，且等方性擴散層之霧度爲 70%以上，因此藉由異向性散射層之高的異向性散射功能 與等方性擴散層之高的等方性散射功能’可使亮度均一化 。第2觀點之光控制薄膜係等方性擴散層之霧度爲60%以 上，且透鏡層相較於異向性擴散層，配置於更接近光射出 面側，因此發揮異向性散射層之高的異向性散射功能與透 鏡層之功能部之透鏡功能的相乘效果，使擴散光集光於正 面方向，可使亮度均一化。 藉此，即使爲要求薄肉化與高亮度化的背光單元也可 抑制燈圖像（lamp image)之產生。特別是本發明之光控制 薄膜爲由光入射面側朝光.射出面側，依序以異向性擴散層 、二片等方性擴散層的順序構成時，可更明顯抑制燈圖像 (lamp image)之產生，實現高亮度化。 此外，將異向性擴散層之分散相之長軸方向與線狀光 源之長軸方向成爲平行的狀態，配設異向性擴散層時，藉 由異方的光散射特性，由線狀光源之光對於線狀光源之長 度方向，可以垂直方向散射，將亮度之降低抑制在最小限 度，可使出射面之亮度均一化，且顯示面可均一照明。即 使異向性擴散層之厚度爲較小的薄肉薄片（例如0.2mm程 度）也可提高背光型液晶顯示裝置之顯示面的亮度。可不 使用以往必要之擴散板，可達到亮度之均一化，因此即使 -51 - 201009397 大型的液晶顯示裝置，也可使裝置薄型化，可簡單製造裝 置。換言之，本發明之光控制薄膜係即使厚度較薄，也可 使大面積之液晶顯示裝置之顯示面以高亮度均一照明。特 別是連續相及分散相以所定樹脂構成，因此耐熱性高，位 於接近線狀光源，產生高溫作用之直下型背光單元，也可 長期間維持所定的異向的光散射。 液晶顯示裝置中，光控制薄膜只要是夾於由背光單元 之出射面出射之光路内、即背光單元與顯示單元之間即可 ，必要時也可使用接著劑，層合於出射面之層合形態進行 配設。更具體而言，光控制薄膜只要配設於面光源單元之 出射面側或顯示單元之入射面側即可，也可配設於背光單 元之出射面與顯示單元之間。又，光控制薄膜也可與稜鏡 薄片、擴散薄片、亮度提高之薄片、相位差薄膜、偏光薄 膜、彩色濾光片等組合使用。特別是在光控制薄膜之出射 面上使用霧度未達60%之擴散薄片時，可防止閃耀，擴大 視角。 此外，背光單元中，線狀光源不需要位於顯示單元之 正下方，也可作爲位於側部之邊緣光型使用。此時，可由 側部之線狀光源的光係由異向性擴散層之側面入射，與該 側面略直交的面（與顯示單元對向的面）進行光射出，照明 顯示單元。線狀光源之數無特別限定，可配合顯示面尺寸 等來選擇。 上述邊緣光型之背光單元，例如使用LED光源等點 狀光源時，光源附近的亮度極高，隨著遠離光源，其亮度 -52- 201009397 有降低的傾向，亮度分布大。此時，依據本發明之光控制 薄膜時，可使光源的光均一出射，對於顯示面之亮度可實 現均一化及高亮度化。 光控制薄膜之X軸方向通常爲異向性擴散層之分散相 的長軸方向。因此，光控制薄膜係將其X軸方向，相對於 背光單元之線狀光源之軸方向（Y軸方向）而言，略平行方 向來配設。光控制薄膜之X軸方向相對於背光單元之線狀 光源之軸方向（Y軸方向），不需完全平行，例如在角度±15°( 例如±10°，特別是±5°)的範圍内，可朝斜方向配設。 【實施方式】 [實施例] 以下藉由實施例更具體說明本發明。其中「份」、「 %」在無特別聲明時爲重量基準。 《1.各層之製作》 《1-1.異向性擴散層之製作》 作爲透明樹脂層用樹脂組成物係使用雙酚A型聚碳酸 酯系樹脂（IUPILON S-2000 :三菱工程塑膠公司' 數平均 分子量：1 8000-20000、熔融流動速率9~12g/10分鐘）， 作爲異向性擴散層用組成物係使用作爲構成連續相之樹脂 (基質樹脂）的聚碳酸酯系樹脂（IUPILON S-2000:三菱工程 塑膠公司）92重量份、作爲構成分散相之樹脂之聚丙烯系 樹脂（WINTECH WFX-4 :日本POLYPRO公司、使用二茂 -53- 201009397 觸媒之丙烯系無規共聚物、熔融流動速率7〜10 g/10分鐘）8 重量份。將構成各層之樹脂組成物予以混合，以多層押出 成形機在樹脂溫度250°C、模頭口徑1.3mm的狀態，由模 頭熔融後進行共擠出，牽伸比（牽伸倍率）爲7.7倍，油溫 調節3支鑄膜輥，以80 °C冷卻，製作在兩面形成透明樹脂 層的異向性擴散層（總厚度：175 μηι、透明樹脂層的厚度： 35μιη、異向性擴散層的厚度：105μιη)。 對於兩面形成透明樹脂層的異向性擴散層依據JIS Κ 73 0 1使用霧度計（NDH-500:日本電色工業公司）測得全光 線透過率爲89%。具有異方度爲14。藉由透過型電子顯微 鏡（ΤΕΜ)觀察剖面時，在異向性擴散層中，聚丙烯系樹脂 形成散射子（粒子狀分散相），粒子狀分散相的形狀係橢圓 體狀（或細長線狀），短軸之平均長度0.20 μιη及長軸之平 均長度133.3μιη(縱橫比667)。 《1-2.等方性擴散層之製作》 將下述處方之等方性擴散層Α用塗佈液進行混合攪拌 後，藉由棒塗佈法塗佈於厚度ΙΟΟμιη之聚對苯二甲酸乙二 酯薄膜（lumirror Τ60 :東麗公司）所構成之支持體上，乾燥 後形成乾燥後之厚度爲2 7 μιη，製作等方性擴散層A。 <等方性擴散層A用塗佈液> 110份 •丙烯酸多元醇 (ACRYDIC A-837 : DIC 公司、固形份 50%) 201009397 •異氰酸酯系硬化劑 22份 (TAKENATE D110N :三井化學 polyurethanes 公司、 固形份60%) •丙烯酸樹脂粒子 110份 (平均粒徑15μιη、變動係數35%) •乙酸丁酯 200份 •甲基乙基酮 200份 將上述等方性擴散層A用塗佈液變更爲下述處方之等 方性擴散層B用塗佈液，乾燥後之厚度調整爲12μπι外， 與上述同樣製作等方性擴散層Β。 <等方性擴散層Β用塗佈液> •丙烯酸多元醇 162份 (ACRYDIC A-807 : DIC 公司、固形份 50%) •異氰酸酯系硬化劑 32份 (TAKENATE D110N :三井化學 polyurethanes 公司、固形份 60%) 丙烯酸樹脂粒子 55份 (MX-1000:綜硏化學公司、平均粒徑ΙΟμπι) •聚矽氧樹脂粒子 1 5份 (tospearl 130 : Momentive Performance Materials.Japan 公司、 平均粒徑3μιη) •乙酸丁酯 200份 •甲基乙基酮 200份 將上述等方性擴散層Α用塗佈液變更爲下述處方之等 方性擴散層C用塗佈液，乾燥後之厚度調整爲12 μηι外， -55- 201009397 與上述同樣製作等方性擴散層c <等方性擴散層C用塗佈液> •丙烯酸多元醇 162份 (ACRYDIC A-807 : DIC 公司、固形份 50%) •異氰酸酯系硬化劑 32份 Φ (TAKENATE D110N :三井化學 polyurethanes 公司、固形份 60%) •丙烯酸樹脂粒子 1 1 0份 (Ganzpearl GM-0605 : Ganz 化成公司、平均粒徑 6μιη) •乙酸丁酯 200份 •甲基乙基嗣 200份 將下述處方之等方性擴散層D用塗佈液塗佈於厚度 ΙΟΟμιη之聚酯薄膜（DiafoilO 300Ε:三菱樹脂公司）所構成 之支持體的單面，成爲厚度2.7 μπι，藉由高壓水銀燈照射 紫外線1〜2秒，製作等方性擴散層D。 ❹ <等方性擴散層D用塗佈液> 1〇〇份 •紫外線硬化型丙烯酸樹脂 (unidic 17-813 : DIC 公司、固形份 80%) 份 •光聚合起始劑 (IRGACURE 651 : CIBA.Japan 公司） 1.6份 •丙烯酸樹脂粒子 200份 (MX-500KS:綜硏化學公司、平均粒徑5μιη) •丙二醇單甲醚 -56- 201009397 《1-3.透鏡層之製作》 在頂角90°、間距爲50μιη之三角柱狀的構造 複數規則性排列所成之模上塗佈下述處方的透鏡層 液，使厚度100μηι之支持體的聚對苯二甲酸乙二 (Cosmoshine Α4100:東洋紡績公司）密著，在聚對 酸乙二酯薄膜與模之間塡充形成與模之稜鏡形狀互 鏡形狀的透鏡層（稜鏡部（功能部）的厚度：25μιη、 域的厚度：5μιη)。 <透鏡層用塗佈液> •丙烯酸單體 (甲基丙烯酸甲酯：和光純藥公司） •多官能性丙烯酸單體 (NK ester Α-ΤΜΡΤ-3ΕΟ :新中村化學工業公司） •光聚合起始劑 (IRGACURE 184: CIBA.Japan 公司） 此外在模上依透鏡層、聚對苯二甲酸乙二酯薄 序層合的狀態，由聚對苯二甲酸乙二酯薄膜側藉由 銀燈照射紫外線600mJ/Cm2，使功能層硬化後，將 ，製作在支持體上所形成的透鏡層。 《2 ·光控制薄膜之製作》 [實施例1] 單位被 用塗佈 酯薄膜 苯二甲 補之稜 基底區 50份 45份 5份 膜的順 高壓水 模剝離 -57- 201009397 將如上述製作的異向性擴散層、等方性擴散層A、等 方性擴散層A依序未密著，而以重疊製作實施例1的光控 制薄膜（等方性擴散層A成爲光射出面側的狀態下配置）。 [實施例2] 將如上述製作的等方性擴散層A、異向性擴散層、等 方性擴散層A依序未密著，而以重疊製作實施例2的光控 制薄膜。 [實施例3] 將如上述製作的等方性擴散層A、等方性擴散層A、 異向性擴散層依序未密著，而以重疊製作實施例3的光控 制薄膜（異向性擴散層成爲光射出面側的狀態下配置）。 [實施例4] 將如上述製作的異向性擴散層、等方性擴散層B、等 方性擴散層B依序未密著，而以重疊製作實施例4的光控 制薄膜（等方性擴散層B成爲光射出面側的狀態下配置）。 [實施例5] 將如上述製作的異向性擴散層、等方性擴散層A、透 鏡層依序未密著，而以重疊製作實施例5的光控制薄膜（ 透鏡層成爲光射出面側的狀態下配置）。 -58- 201009397 [實施例6] 將如上述製作的等方性擴散層A、異向性擴散層、透 鏡層依序未密著，而以重疊製作實施例6的光控制薄膜（ 透鏡層成爲光射出面側的狀態下配置）。 [實施例7] 將如上述製作的異向性擴散層、透鏡層、等方性擴散 層A依序未密著，而以重疊製作實施例7的光控制薄膜（ 等方性擴散層A成爲光射出面側的狀態下配置）。 [實施例8] 將如上述製作的異向性擴散層、等方性擴散層B、透 鏡層依序未密著，而以重疊製作實施例8的光控制薄膜（ 透鏡層成爲光射出面側的狀態下配置）。 φ [實施例9] 將如上述製作的異向性擴散層、等方性擴散層C、透 鏡層依序未密著，而以重疊製作實施例9的光控制薄膜（ 透鏡層成爲光射出面側的狀態下配置）。 [比較例1] 將如上述製作的異向性擴散層、等方性擴散層C、等 方性擴散層C依序未密著，而以重疊製作比較例1的光控 制薄膜（等方性擴散層C成爲光射出面側的狀態下配置）。 •59- 201009397 [比較例2] 將如上述製作的異向性擴散層、等方性擴散層D、等 方性擴散層D依序未密著，而以重疊製作比較例2的光控 制薄膜（等方性擴散層D成爲光射出面側的狀態下配置）。 [比較例3] 將如上述製作的異向性擴散層、等方性擴散層A依序 未密著，而以重疊製作比較例3的光控制薄膜（等方性擴 散層A成爲光射出面側的狀態下配置）。 [比較例4 ] 將如上述製作的異向性擴散層與透鏡層依序未密著， 而以重疊製作比較例4的光控制薄膜（透鏡層成爲光射出 面側的狀態下配置）。 ❹ [比較例5] 將如上述製作的異向性擴散層、等方性擴散層D、透 鏡層依序未密著，而以重疊製作比較例5的光控制薄膜（ 透鏡層成爲光射出面側的狀態下配置）。 [比較例6] 將如上述製作的透鏡層、異向性擴散層、等方性擴散 層A依序未密著，而以重疊製作比較例6的光控制薄膜（ -60- 201009397 等方性擴散層A成爲光射出面側的狀態下配置）。 [比較例7] 將如上述製作的等方性擴散層A、透鏡層、異向性擴 散層依序未密著，而以重疊製作比較例7的光控制薄膜（ 異向性擴散層成爲光射出面側的狀態下配置）。 [比較例8] 將如上述製作的透鏡層、等方性擴散層A、異向性擴 散層依序未密著，而以重疊製作比較例8的光控制薄膜（ 異向性擴散層成爲光射出面側的狀態下配置）。 [比較例9] 將如上述製作的異向性擴散層與透鏡層依序未密著， 而以重疊製作比較例9的光控制薄膜（透鏡層成爲光射出 • 面側的狀態下配置）。 《3.背光裝置之製作》 其次，在32吋之直下型背光裝置（冷陰極管（線狀光源 )16燈）的冷陰極管上設置實施例1〜9及比較例1〜9的光控 制薄膜，作爲實施例1 ~9及比較例1〜9的背光裝置。所有 的實施例及比較例係將其異向性擴散層之粒子狀分散相的 長軸方向與線狀光源之軸方向平行的狀態，設置光控制薄 膜。 -61 - 201009397 《4.評價》 (1) 等方性擴散層之霧度 使用霧度計（HGM-2K: SUGA試驗機公司），依據JIS K71 36 : 2000測定使光由實施例1〜9及比較例1〜9之光控 制薄膜所使用之等方性擴散層A〜D之擴散面入射時的霧 度。測定結果如表1及表3所示。 (2) 重叠等方性擴散層時的霧度 使用霧度計（HGM-2K: SUGA試驗機公司），依據JIS K7 1 36 : 2000測定取出實施例1~4及比較例1〜2之光控制 薄膜所使用之二片等方性擴散層A~D，在各實施例及比較 例中重叠，使光由該等方性擴散層之擴散面入射時之霧度 。測定結果如表1所示。 (3) 正面亮度 測定使用實施例1〜9及比較例1~9之光控制薄膜之直 下型背光裝置之光射出面中心的正面亮度。測定結果如表 2及表3所示（單位爲「Cd/m2」）。 (4) 燈圖像（lamp image)之消除性 點亮實施例1〜9及比較例1〜9之背光裝置時，對於背 光單元之正面方向的燈圖像以目視確認。燈圖像以目視時 ，完全無法確認者評價爲「◎◎」，幾乎未發現燈圖像者 -62- 201009397 評價爲「◎」，可確認若干燈圖像，但是不影響使用者評 價爲「〇J ，可確認燈圖像者評價爲「X」。評價結果如 表2及表3所示。 [表1] 構成(光入射面―光射出面） 等方性擴散 層之霧度(％) 複合霧度※ (%) 實施例1 異向性擴散層，等方性擴散層A，等方性擴散層A 91 96 實施例2 等方性擴散層A,異向性擴散層，等方性擴散層A 91 96 實施例3 等方性擴散層A,等方性擴散層A，異向性擴散層 91 96 實施例4 異向性擴散層，等方性擴散層B，等方性擴散層B 84 93 比較例1 異向性擴散層,等方性擴散層C,等方性擴散層C 67 84 比較例2 異向性擴散層，等方性擴散層D，等方性擴散層D 46 73 比較例3 異向性擴散層，等方性擴散層A 91 _ 比較例4 異向性擴散層，菱鏡薄片 _ 一 ※表中之「複合霧度」係指重疊二片等向性擴散層之霧度。 [表2][Technical Field] The present invention relates to a light control film suitable for use as a member constituting a backlight device for use in a liquid crystal display or the like, and a backlight device using the same. [Prior Art] A backlight unit is provided on the back surface of the display panel by a back-illuminated backlight type display device (liquid crystal display device) for a display panel (such as a liquid crystal display module). The irradiation light of the display panel is uniformed as a surface light source, and in order to increase the front luminance of the liquid crystal display device, a diffusion plate, a diffusion sheet, a ruthenium sheet, a brightness enhancement sheet (reflective polarizing plate, etc.), or the like is used. Further, in the liquid crystal display device, a polarizing plate, a phase difference plate, a color filter or the like is also used as a constituent member of the liquid crystal cell. An example of a backlight using a fluorescent discharge tube (linear light source, cold cathode tube) is proposed. For example, Patent Document 1 discloses a tubular light source including light incident from the side surface of the φ tubular light source and reflected by the flat reflecting surface, and a light guiding member for illuminating the display unit, and the light guiding member and the display unit. And a surface light source unit of at least one anisotropic light-scattering film for uniformly illuminating the display unit by the light of the tubular light source. The anisotropic light-scattering film having the surface light source unit is a laminated resin film in which a transparent resin layer is laminated on both surfaces of the anisotropic scattering layer. The anisotropic light-scattering layer is composed of a continuous phase composed of a resin and a dispersed phase composed of a resin having an average aspect ratio of 5 to 1000 dispersed in the continuous phase and having a refractive index different from that of the resin of the continuous phase. The anisotropic scattering layer is composed of a combination of a propylene resin and a styrene resin of -5 - 201009397 or a combination of a propylene resin and a polycarbonate resin. The transparent resin layer is composed of the same resin as the above-mentioned continuous phase, and is composed of a transparent resin having a glass transition temperature or a melting point of 130 to 280 °C. The plurality of anisotropic light-scattering films are disposed between the light guiding member and the display unit in a state in which the directivity of light scattering is different from each other. Further, in the backlight device, a method of improving the light diffusibility is a method of forming a plastic sheet into a lens shape, and a method of combining such a lens shape and a light diffusing function using a light diffusing agent has been proposed. For example, in the diffusion plate for a direct type light source device disclosed in Patent Document 2, the surface of the resin plate in which the light diffusing agent is disposed is formed into a matrix, and the convex portion and the concave portion of the array are both curved and concave. A high diffusion plate having a radius of curvature smaller than a radius of curvature of the convex portion. Further, Patent Document 2 discloses that the base resin as the resin sheet is an acrylic resin, a polycarbonate resin, a styrene resin, an MS resin, an MBS resin, PE, PET, SAN, an alicyclic acrylic resin, an alicyclic polyolefin resin, An olefin-maleimide-interpolymer, a cycloethylene-based polymer, an amorphous polyester resin, an amorphous fluorine-based resin, or the like. Patent Document 3 discloses a light scattering film which can scatter incident light in the direction in which light is emitted, and a scattering characteristic F(e) indicating a relationship between a scattering angle Θ and a scattered light intensity F, in which the scattering characteristic of the film in the X-axis direction is When the scattering characteristic in the Fx(e) and Y-axis directions is Fy(e), the anisotropic light scattering satisfying the formula: Fy(0)/FX(0)>5 in the range of θ = 4~30° film. In Patent Document 3, a film in which the continuous phase is a crystalline olefin resin and the dispersed phase is an amorphous polyester resin is also described. Further, a film formed on the surface of the film to form a concavo-convex portion extending in the X-axis direction of the film is also described. 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 [Explanation] [Explanation of the Invention] [Problems to be Solved by the Invention] φ However, when the unit of Patent Document 1 is used for a backlight type display device which has been increased in brightness and thickness in recent years, the display surface The uniformity of brightness is insufficient to leave a lamp image. Although a combination of a polycarbonate resin and a polypropylene resin is described in Patent Document 1, the details of the two resins and specific adjustment methods are described. Therefore, in order to produce a film which does not have voids and has excellent light-scattering properties, it is necessary to prepare a compatibilizing agent, and it is difficult to adjust the sheet. The diffusion plate of Patent Document 2 is a dispersion Φ phase composed of a light diffusing agent. Isometric, so the uniformity of brightness is insufficient. In addition, since the heat resistance of the diffusing plate is low, the film may be deformed when the diffusing plate is used in a high temperature environment, such as a device in which the light source is not directly irradiated from the back surface (direct type), or in a high temperature environment, or When the thermal stability of the matrix phase is low, the shape of the contracted or dispersed phase changes due to the deformation accompanying the extension, and thus the light diffusion property changes, and the brightness of the transmitted light cannot be uniformized. In the anisotropic light-scattering film of Patent Document 3, since the shape of the uneven portion on the surface is small, the lens effect is insufficient, and the uniformity of the brightness of the display surface is insufficient, and the lamp image remains. Further, the anisotropic light-scattering thin film of Patent Document 3 201009397 has a low heat resistance. Therefore, the device of the direct type has a change in light diffusion characteristics. The brightness of the transmitted light cannot be uniformized. An object of the present invention is to provide a light source control device such as a backlight type liquid crystal display device, and a light control film and a backlight device which can be made thinner and brighter. Another object of the present invention is to provide a light control film which can suppress variations in light diffusion characteristics even when used at a high temperature, and a backlight device using the same. [Means for Solving the Problems] In order to solve the above problems, the inventors of the present invention have found that at least two or more isotropic diffusion layers exhibiting equal diffusivity and diffusion in an opposite direction are found by (1) When the isotropic diffusion layer constitutes a light control film, and the haze of the isotropic diffusion layer is 70% or more, a surface light source device such as a backlight type liquid crystal display device can be obtained without detecting a state of the lamp image. The invention is made thinner and brighter, and the present invention has been completed. In addition, (2) a light-diffusing anisotropic diffusion layer that exhibits an opposite light diffusing property, a Q-like isotropic diffusion layer that exhibits equal light diffusibility, and a lens layer having a specific structure portion constitute a light control film. The haze of the isotropic diffusion layer of the light control film is set to 60% or more, and the lens layer is disposed closer to the light exit surface than the anisotropic diffusion layer, and the same effect as the above-described invention can be achieved. invention. In other words, according to the first aspect of the present invention, it is possible to provide a light control film which is characterized in that it comprises at least two or more isotropic diffusion layers and an anisotropic diffusion layer, and the isotropic diffusion layer is fogged. The degree is 70% or more. According to a second aspect of the present invention, a light control film can be provided, which is characterized in that it comprises at least a lens layer, an isotropic diffusion layer and an anisotropic diffusion layer, and the isotropic diffusion layer The haze is 60% or more, and the lens layer is formed closer to the light-emitting surface than the anisotropic diffusion layer. In the above invention, the anisotropic diffusion layer may contain a continuous phase composed of a transparent resin and a particulate dispersed phase having a refractive index different from that of the continuous phase and a direction in which the major axis direction is aligned. Further, when the two or more isotropic φ diffusion layers are stacked, the haze can be 90% or more. The lens layer may have a structural portion in which a plurality of structures having a geometrical shape in cross section are regularly arranged. According to the present invention, there can be provided a backlight device comprising a linear light source and any of the above light control films disposed on the linear light source. In the present invention, the long axis direction of the particulate dispersed phase of the anisotropic diffusion layer is in a state parallel to the axial direction of the linear light source, and the light control film is disposed. The light control film is disposed in the order of an isotropic diffusion layer and two or more isotropic diffusion layers on the linear light source side. Further, the light control film is disposed in the order of the anisotropic diffusion layer, the isotropic diffusion layer, and the lens layer from the linear light source side. In the present specification, the term "film" means a sheet regardless of the thickness. "Haze" means the haze specified in JIS K7 1 36:2000. [Effect of the Invention] The light control film of the first point constitutes a light control film by at least two or more isotropic diffusion layers that exhibit equal diffusivity and an anisotropic diffusion layer that exhibits diffusivity in an anisotropic manner. Further, the haze of the isotropic diffusion layer is 70% or more. Therefore, a lamp image is not generated, and a backlight device such as a backlight type liquid crystal display device of 201009397 can be made thinner and brighter. The light control film of the second aspect is composed of at least a lens layer, an isotropic diffusion layer, and an anisotropic diffusion layer, and the haze of the isotropic diffusion layer of the light control film is 60% or more, and the lens layer ratio is Since the anisotropic diffusion layer is disposed closer to the light-emitting surface side, a lamp image is not generated, and a backlight device such as a backlight-type liquid crystal display device can be made thinner and brighter. Further, the light control film of the present invention can suppress the appearance of a lamp image by itself, and therefore, when used in a backlight device, the conventional diffusion plate itself can be omitted. Further, when the film is controlled by the light of the first dot, the brightness in the front direction can be increased, so that the thin film for collecting light can be omitted. According to the backlight device using the light control film of the present invention, it is possible to achieve a reduction in thickness, a reduction in material cost, and a reduction in assembly processing cost compared to the conventional backlight device, which not only greatly reduces the cost but also contributes to the improvement of the display body. brightness. [Best Mode for Carrying Out the Invention] "Light Control Film" First, a light control film according to an embodiment of the present invention will be described. The light control film of the first aspect is composed of at least two or more isotropic diffusion layers and an anisotropic diffusion layer, and the haze of the isotropic diffusion layer is 70% or more. The light control film of the second aspect is composed of at least a lens layer, an isotropic diffusion layer, and an anisotropic diffusion layer, and the haze of the isotropic diffusion layer of the light control film is 60% or more. The layer is 201009397 which is closer to the side of the light exiting surface than the anisotropic diffusion layer. In the following, unless otherwise stated, both the first viewpoint and the second viewpoint of the present invention are used. "Anisotropic Diffusion Layer" First, the anisotropic diffusion layer will be described. The anisotropic diffusion layer is composed of a continuous phase composed of a transparent resin and a particulate dispersed phase having a refractive index different from that of the continuous phase and having a major axis φ direction aligned in one direction. The transparent resin constituting the continuous phase contains a thermoplastic resin (olefin resin, cyclic olefin resin, halogen-containing resin (including fluorine resin), vinyl alcohol resin, vinyl ester resin, vinyl ether resin, (methyl) Acrylic resin, styrene resin, polyester resin, polyamine resin, polycarbonate resin, thermoplastic polyurethane resin, polyfluorene resin (polyether oxime, polyfluorene, etc.), Polyphenylene ether resin (polymer of 2,6-xylenol, etc.), cellulose derivative (cellulose ester, cellulose urethane, fiber #维素 ether, etc.), polyoxyl resin (polydimethyl siloxane, polymethylphenyl siloxane, etc.), rubber or elastomer (diene rubber, polyisoprene, etc., styrene-butadiene copolymer) , acrylonitrile-butadiene copolymer, acrylic rubber, urethane rubber, polyoxyethylene rubber, etc.), and thermosetting resin (epoxy resin, unsaturated polyester resin, diallyl benzene) Dicarboxylate resin, polyfluorene oxide resin, etc.). These transparent resins may be used singly or in combination of two or more. Among these transparent resins, a polycarbonate resin is preferred. The polycarbonate resin contains an aromatic polycarbonate-11-201009397 ester based on bisphenols. Examples of the bisphenols include bisphenols such as dihydroxybiphenyl; bis(hydroxyaryl)alkanes such as bisphenol A, bisphenol F, and bisphenol AD; and bis(hydroxyphenyl)cyclohexane; a hydroxyaryl)cycloalkane; a bis(hydroxyphenyl)ether such as 4-4'-bis(hydroxyphenyl)ether; a bishydroxyphenyl group such as 4-4'-bis(hydroxyphenyl) ketone a ketone; a bis(hydroxyphenyl) anthracene such as bisphenol S; a bis(hydroxyphenyl) maple; a bisphenolphthalein such as 9_9_bis(4-hydroxyphenyl)anthracene. These bisphenols may be C2-4 epoxy compound adducts. These bisphenols may be used singly or in combination of two or more. The polycarbonate resin may be a polyester carbonate resin obtained by copolymerizing a dicarboxylic acid component (aliphatic, alicyclic or aromatic dicarboxylic acid or an acid halide thereof). These polycarbonate resins may be used singly or in combination of two or more. A preferred polycarbonate resin is a resin based on bis(hydroxyphenyl)-6 alkane, for example, a bisphenol A polycarbonate resin. The number average molecular weight of the polycarbonate resin may be selected from the range of 10,000 to 50,000 (e.g., 15,000 to 30,000), for example, 12,500 to 30,000 (e.g., 15,000 to 25,000), preferably 17,000 to 25,000 (e.g., 18,000 to 22,000). When the molecular weight of the polycarbonate resin is too small, the strength of the film is lowered, and when the molecular weight is too large, the melt dispersibility and the uniform dispersibility of the dispersed phase are liable to lower. When the polycarbonate resin and the specific polypropylene resin are combined, voids do not occur even if the compatibilizing agent is not used, and a relatively high aspect ratio dispersion phase can be formed. The melt flow rate (MFR) of the polycarbonate resin is based on IS01 1 33 (300 ° C, 1.2 kg load (11.8 N)), and may be selected, for example, from about 3 to 30 g/10 minutes (for example, 4 to 20 g/10). The range of minutes) is usually about 5 to 30 gM0 minutes (for example, 5 to 15 g/10 minutes), preferably 6 to 25 g/10 minutes 201009397 (for example, 7 to 2 g/l〇 minutes). It is 8 to 15 g/10 minutes (for example, 9 to 12 g/10 minutes). The melting point or glass transition temperature of the polycarbonate resin is, for example, 130 to 280 ° C, preferably about 140 to 270 ° C, more preferably 150 to 260 ° C. Such polycarbonate resins are classified in the product catalogue and are classified into "medium viscosity products", "low viscosity products", and "high flow" grades. In the transparent resin similar to the above-mentioned continuous phase, the dispersed phase may be used alone or in combination of two or more kinds of resins having different refractive indices from the resins constituting the continuous phase. Among these transparent resins, a transparent resin which forms a dispersed phase is preferred, and a polypropylene resin is preferred. The polypropylene resin contains a copolymer of polypropylene (homopolymer), propylene and a copolymerizable monomer. Examples of the copolymerizable monomer include olefins (in addition to ethylene, a-C4-1Q olefins such as butene, pentene, heptene, hexene, etc.) and (meth)acrylic monomers (for example, (methyl)). Acrylic acid, alkyl (meth)acrylate, hydroxyalkyl (meth)acrylate, glycidyl (meth)acrylate, etc., aliphatic vinyl esters (such as vinyl acetate), dienes, and the like. These copolymerizable monomers may be used singly or in combination of two or more. Among these copolymerizable monomers, a-olefins (ethylene, butylene, etc.) are mostly used. The propylene content in the propylene-based copolymer is 80 mol% or more (soy 00 mol%) ‘ is preferably 85 mol% or more, more preferably 90 mol% or more. The propylene-based copolymer may also be a block copolymer or the like, and usually it is usually a random copolymer. Preferred polypropylene resins are polypropylene homopolymers, propylene-ethylene copolymers, propylene-butene copolymers, propylene-ethylene-butene copolymers, and the like. Polypropylene -13- 201009397 Most of the olefinic polymers are polypropylene homopolymers and propylene-ethylene copolymers. The polypropylene resin may be a polymer using a Ziegler catalyst or the like, and is preferably a ferrocene-based resin using a metallocene catalyst. The bislocene-based resin has a characteristic of a narrow molecular weight distribution, a low molecular weight component, and a low crystal component. Therefore, even if the dissolving agent is not used, the polypropylene resin phase (dispersed phase) can be uniformly dispersed in the matrix phase of the polycarbonate resin. In the gel permeation chromatography (GPC), the molecular weight of the polypropylene resin is, for example, a weight average molecular weight Mw/number average molecular weight Mn = 1 to 2.5 (for example, 1.2 to 2.3), preferably 1.3 to 2 ( For example, 1.5 to 1.8), usually 1.3 to 2.5 (for example, 1.5 to 2.0). The weight average molecular weight Mw of the polypropylene resin is, for example, lxlO4 to ΙΟΟχΙΟ4, preferably 2 χ 104 to 75 χ 104 (e.g., 3 χ 104 to 50 χ 104), more preferably 3 x 10 4 to 3 〇χ 104. In the GPC, the content of the low molecular weight component having a molecular weight of 10,000 or less is, for example, 1% by volume or less, preferably 0.5% by volume or less, more preferably 0.3% by volume or less. The device for molecular weight and molecular weight distribution by GPC was: Waters Alliance Q GPCV-2000, column: PL2 (^m MIXED-A, detector: RI, solvent: hydrazine-dichlorobenzene, and the temperature was measured at 135 °C. The above molecular weight and molecular weight distribution are monopropylene-based polystyrene as a reference material, and the polypropylene-based enthalpy corrected by a general-purpose calibration curve method. The MFR of the polypropylene-based resin is based, for example, on JIS K72 1 0 (230 ° C, 2-16 kg load) (21_2N)), for example, 3 to 20 g/10 min, preferably 4 to 15 g/10 min, more preferably 5 to 10 g/10 min. The polypropylene resin may be crystalline, and the crystalline polypropylene resin may be knotted. 14- 201009397 The degree of crystallization is, for example, Μ-80%, preferably 20 to 7 〇 ° /. More preferably 30 to 60%. The melting point of the polypropylene resin (the melting peak temperature of the differential scanning calorimeter DSC) For example, l〇〇~HO ° C, preferably ll 〇 135 ° C, more preferably 1 15 〜 130 ° C (for example, 120 〜 130 ° C). The polypropylene resin is preferably a copolymer (propylene). - an ethylene random copolymer or the like) or a di-based resin using a di-catalyst is particularly preferably a di-based copolymer. When the polypropylene resin and the polycarbonate resin are used as described above, substantially no voids can form a dispersed phase (the dispersion having a predetermined aspect ratio is equivalent) even if the melt-free agent is not contained. The difference between the melting point or the glass transition temperature of the resin (for example, a polycarbonate resin) constituting the continuous phase (for example, a polypropylene resin) is, for example, 10 to 200 ° C, preferably 30 to 150 ° C, more preferably 50 to 120 ° c 比例 The ratio of the MFR of the resin constituting the continuous phase (for example, a polycarbonate resin) to the MFR of the resin constituting the dispersed phase (for example, a polypropylene resin) is the former/the latter = 〇 _ 8 / 1 ～2.5/1 (for example, 0.9/1 to 2.3/1), preferably 1/1 to 2/1, more preferably 1.2/1 to 1.7/1. In order to impart light diffusibility, the continuous phase and the dispersed phase are The difference in refractive index between the continuous phase (for example, a polycarbonate resin) and the dispersed phase (for example, a polypropylene resin) is, for example, 0.001 or more (for example, 0.001 to 0.3), preferably 0·01~0.3, more preferably 0.01~0.1 〇 anisotropic diffusion layer, continuous The ratio to the dispersed phase is matched with the type of the resin -15-201009397 or the melt viscosity, light diffusibility, etc., and may be selected, for example, from the former/the latter (weight ratio) = 99/1 to 3 0/70 (for example, 95/5-40). /60) The range of left and right, for example, 99/1 to 5 0/50 (for example, 95/5 to 50/5 0), preferably 99/1 to 75/25 (for example, 93/7 to 70/30), More preferably 95/5-60/40, especially good for 90/1 0~75/25. When the polycarbonate resin and the polypropylene resin are combined, not only the practical thermal stability but also the dispersing phase is easily deformed at an alignment treatment temperature such as a uniaxial stretching temperature, and anisotropic diffusion of the transmitted light can be obtained. Film. Further, the aspect ratio of the dispersed phase particles can be controlled by the alignment treatment such as the draft ratio or the uniaxial stretching in the extrusion molding step, and the dispersed phase having a relatively large aspect ratio can be easily formed. Further, since the continuous phase is composed of a polycarbonate resin, heat resistance or blocking resistance can be improved. Further, a matrix phase (continuous phase) is formed of a polycarbonate resin, and a dispersed phase is formed of a polypropylene resin, whereby heat resistance is high, and even when used at a high temperature, a change in light diffusion characteristics over a long period of time can be suppressed. The anisotropic diffusion layer may contain a compatibilizing agent as necessary. When a phase melting agent is used, the mixing property and affinity of the continuous phase and the dispersed phase can be improved, and even if the film is subjected to the alignment treatment, the formation of defects (voids or the like) can be prevented, so that the transparency of the film can be prevented from being lowered. Further, the adhesion between the continuous phase and the dispersed phase can be improved, and even if the film is uniaxially stretched, the dispersed phase can be lowered to adhere to the stretching device. The compatibilizing agent is, for example, a modified olefin-based resin modified with a bisoxazoline compound, a modified group (carboxyl group, acid anhydride group, epoxy group, oxazoline group, etc.) or a polymer containing a diene or a rubber (for example) a homopolymer of a diene monomer such as butadiene or isoprene, or a diene monomer and a copolymerizable monomer (such as an aromatic vinyl monomer such as -16-201009397 styrene) a diene-based graft copolymer obtained by copolymerization of a diene copolymer (random copolymer or the like); an acrylonitrile-butadiene styrene copolymer (ABS resin) or the like; styrene-butadiene (SB) Block copolymer, hydrogenated styrene-butadiene (SB)-block copolymer, hydrogenated styrene-butadiene-styrene block copolymer (SEBS), hydrogenation (styrene-ethylene/butylene-benzene a diene block copolymer such as an ethylene) block copolymer or a hydride such as the above, or a polymer containing a diene or a rubber φ modified with the above modified group (epoxy group or the like) Segment copolymer, etc.). These compatibilizing agents may be used singly or in combination of two or more. Examples of the diene monomer such as a conjugated diene include butadiene, isoprene, 1,3-pentadiene, 2,3-dimethyl-1,3-butadiene, and pentadiene. A C4.2Q conjugated diene which may have a substituent such as (1,3-pentadiene), 3-butyl-1,3-octadiene or phenyl-1,3-butadiene. The conjugated diene may be used singly or in combination of two or more. Among these conjugated dienes, butadiene and isoprene are preferred. Examples of the aromatic vinyl monomer include styrene, (X-methylstyrene, ethylenyltoluene (p-methylstyrene), p-tert-butylstyrene, divinylbenzene, etc.) Among the aromatic vinyl monomers, styrene is preferred. These monomers may be used singly or in combination of two or more. The modified ones are monomers corresponding to the modified groups (for example, a carboxyl group (methyl group) a carboxyl group-containing monomer such as acrylic acid, an acid anhydride group-modified maleic anhydride, an ester-modified methyl (meth)acrylic monomer, a maleic imide-modified maleimide monomer, The epoxy group-containing (epoxy group-containing monomer such as (meth)acrylic acid glycidyl ester) is copolymerized, and the epoxy modification can also be carried out by epoxidation of an unsaturated double bond. -17- 201009397 The compatibilizing agent is usually a polymer (random, block or graft copolymer) having the same or a common component as the structural resin of the polymer blending system, and a structural resin relative to the polymer blending system. A polymer having affinity (random, block or graft copolymer) and the like. Preferably, the phase-dissolving agent is a modified or modified diene-based copolymer, particularly a modified block copolymer (for example, an epoxidized styrene-butadiene-styrene (SBS) block copolymer) An epoxidized diene block copolymer or an epoxy-modified diene block copolymer. The epoxidized diene block copolymer has high transparency and a softening temperature of about 7 (TC). In a plurality of combinations of a continuous phase (for example, a polycarbonate resin) and a dispersed phase (for example, a polypropylene resin), the resin is phase-dissolved to uniformly disperse the dispersed phase. The block copolymer may be, for example, a conjugated diene. The block or a partially hydrogenated block thereof is composed of an aromatic ethylene block. In the epoxidized diene block copolymer, part or all of the double bond of the aforementioned conjugated diene is epoxidized. The ratio (weight ratio) of the conjugated diene block (or its hydrogenated block) is, for example, the former/the latter = about 5/95 to 80/20 (for example, about 25/75 to 80/20). It is 10/90 to 70/30 (for example, about 30/70 to 70/30), usually about 50/50 to 80/20. The number average molecular weight may be selected, for example, to the extent of 5,000 to 1,000,000, preferably about 7,000 to 900,000, more preferably about 10,000 to 800,000. The molecular weight distribution [weight average molecular weight (Mw) to number average molecular weight (??) (Mw/Mn)] is, for example, 10 or less (about 1 to 10), preferably about 1 to 5. The molecular structure of the block copolymer may be linear, branched, or radial -18-201009397 or this. The block structure of the block copolymer may have, for example, a multi-block structure such as a monoblock structure or a teleblock structure, a three-chain radial star structure, a four-chain radial star structure, or the like. When the aromatic diene block is referred to as X or a conjugated diene block as Y, for example, χγ type, XYX type, YXY type, γ-χ_γ-χ type, χ_γ.χ_γ type, χ- Γ_χ_γ_ X type, Υ-Χ-Υ-Χ-Υ type, (X_Y_) 4Si type, (Y-X_) 4Si type, and the like. The proportion of the epoxy group in the epoxidized diene block copolymer is not particularly limited, and the oxygen concentration of ethylene oxide is, for example, 0. 1 to 8 wt%, preferably 0.5 to 6 wt%, more preferably 1 to 5 wt%. The epoxy equivalent weight (JIS K 723 6) of the epoxidized block copolymer is, for example, about 300 to 1,000, preferably about 500 to 900, more preferably about 600 to 800. The refractive index of the compatibilizing agent (epoxidized block copolymer or the like) may be approximately the same as that of the dispersed phase resin (for example, the refractive index difference from the polypropylene resin is about 0 to 0.01, preferably 0 to 0.005, particularly good). For 0.001~0.005). The epoxidized block copolymer is a olefinic block copolymer (or a partially hydrogenated block copolymer) by a conventional epoxidation process, for example, in an inert solvent, using an epoxidizing agent (peroxide). The above block copolymer can be produced by an epoxidation method, such as hydrogen peroxide or the like. The amount of the compatibilizing agent used may be, for example, 0.1 to 20% by weight, preferably 0. 5 to 15% by weight, based on the total amount of the resin composition (for example, the total amount of the polycarbonate resin and the polypropylene resin). More preferably, it is in the range of 1 to 10% by weight. As described above, in the present invention, by dispersing the specific polycarbonate resin and the specific polypropylene resin, the dispersed phase can be uniformly dispersed without containing the compatibilizing agent. Even in the case of aligning treatment such as uniaxial stretching, an anisotropic light-diffusing layer having no voids and high transmittance can be formed -19-201009397. In the preferred anisotropic light-diffusing layer, the ratio of the continuous phase, the dispersed phase and the compatibilizing agent is, for example, as shown below. (1) Continuous phase/dispersion phase (weight ratio) = 99/1 to 50/50, preferably 97/3 to 60/40, more preferably 95/5 to 70/3 0, particularly preferably 90/10 ～80/20, (2) Disperse phase/combustion agent (weight ratio) = 100/0 to 50/50, preferably 99/1 to 70/3 0, more preferably 98/2 to 80/20. In the present invention, by combining the polycarbonate-based resin and the polypropylene-based resin, the dispersed phase can be uniformly dispersed without containing a compatibilizing agent. When each component is used in such a ratio, it is not necessary to combine the components in advance, and even if the particles of the respective components are directly melt-mixed, the dispersed phase can be uniformly dispersed, and the occurrence of voids can be prevented by the alignment treatment such as uniaxial stretching. High transmittance, with an anisotropic light diffusion layer. More specifically, for example, when a resin composition containing a polycarbonate resin as a continuous phase and a polypropylene resin as a dispersed phase in the above ratio is used, it is easy to be composited, and only a raw material is supplied, and on the other hand, it is composited. On the one hand, the film is formed by melting, and even if uniaxial stretching is performed, an anisotropic diffusion layer having no voids can be formed. In addition to the polypropylene resin, a polyethylene resin, a styrene resin, an aromatic polyester resin (polyalkylene terephthalate, polynaphthalene diester, etc.) a copolyester having a content of 80% by mole or more of a polyalkylene aryl ester unit, a liquid crystalline aromatic polyester, or the like, and a polyamide resin (polyamide 46, polyamine 6' polyamide 66) A polymer such as an aliphatic polyamine or the like, or an inorganic particle such as cerium oxide can also be used as a component of the dispersion of -20-201009397. The anisotropic diffusion layer may contain conventional additives such as stabilizers (antioxidants, ultraviolet absorbers, heat stabilizers, light stabilizers, etc.), plasticizers, antistatic agents, flame retardants, and the like. Examples of the antioxidant include a phenolic antioxidant, a hydroquinone antioxidant, a quinoline antioxidant, and a sulfur antioxidant. Among the phenolic antioxidants, preferred are: hindered phenols, for example, 2,6-di-t-butyl-p-cresol, 2,2'-methylene-p-bis (4-methyl-6-tributyl) Alkylphenol-based antioxidants such as phenols, 2,2'-thiobis(4-methyl-6-tert-butylphenol); n-octadecyl [3-(3,5-di) C1G-3 5 alkyl [3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate] such as tributyl-4-hydroxyphenyl)propionate]; 1,6 _Hexanediol bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate] C2_1() alkanediol bis[3-(3,5-di-third butyl) Hydroxy C2_4 alkane, such as tris-hydroxyphenyl)propionate; triethylene glycol bis[3-(3-t-butyl-5-methyl-4-hydroxyphenyl)propionate] Alcohol bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate]; glycerol tris[3-(3,5-• di-t-butyl-4-hydroxyphenyl) Propionate], etc. C3_8 alkanol tris[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate]; pentaerythritol tetra-[3-(3,5-di-third) (-4-hydroxyphenyl)propionate] (: 4-8 alkyltetraol tetra [3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate]; N, N'-extension hexyl double (3,5- Tertiary-butyl-4- hydroxyhydrocinnamate Amides), etc.! <^-(: 2-1() alkyl bis(3,5-di-t-butyl-4-hydroxyhydrocinnamylamine), etc. Among the amine-based antioxidants, the hindered amines include, for example, 1, 2 -bis(2,2,6,6-tetramethyl-4-piperidinyloxy)ethane, phenylnaphthylamine, N,N'-diphenyl-1,4-phenylenediamine, N-phenyl- Ν'-cyclohexyl-1,4-phenylenediamine, etc. -21 - 201009397 The hydroquinone antioxidant includes, for example, 2,5-di-tert-butylhydroquinone; and the quinoline-based antioxidant includes, for example, 6 -Ethoxy-2,2,4-trimethyl-1,2-dihydroxyquinoline, etc. Further, the sulfur-based antioxidant includes, for example, dilaurylthiodipropionate and distearylsulfonate. Dipropionate, etc. The ultraviolet absorber is, for example, phenyl salicylate or 2,4-di-t-butylphenyl-3,5-di-t-butyl-4-hydroxybenzoate. Acid ester ultraviolet absorber; 2-(2-hydroxy-5-methylphenyl)benzotriazole, 2·[2-hydroxy-3-(3,4,5,6-tetrahydrophthalic acid)醢iminomethyl)-5-methylphenyl]benzotriazole, 2-[3-t-butyl-2-hydroxy-5-methylphenyl]-5-chlorobenzotriazole, 2 -(2-hydroxy-5-t-butylphenyl)benzotriazole, 2-( 2-hydroxy-3,5-di-t-butylphenyl)benzotriazole, 2-(2-hydroxy-3,5-bis(α,α-dimethylbenzyl)phenyl)benzotriene Oxazole, octyl-3-[3-tert-butyl-4-hydroxy-(5-chloro-2H-benzotriazol-2-yl)phenyl]propionate, 2-(2H-benzotriazole Zin-2-yl)-4,6-bis(l-methyl-l-phenylethyl)phenol, 2-(2H-benzotriazol-2-yl)-6-(1-methyl- a benzotriazole-based ultraviolet absorber such as 1-phenylethyl)-4-(1,1,3,3-tetramethylbutyl)phenol; 2-hydroxybenzophenone, 2-hydroxy-4 a benzophenone-based ultraviolet absorber such as methoxybenzophenone, 2-hydroxy-4-octyloxybenzophenone or 2,2'-dihydroxy-4-methoxybenzophenone ; 2_(4,6_bis(2,4-dimethylphenyl)-1,3,5-triazin-2-yl)-5-hydroxyphenyl and ethylene oxide reaction product, 2- Reaction of (2,4-dihydroxyphenyl)-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine) with 2-ethylhexyl glycidyl ester Hydroxyphenyltriazine of 2,4-bis[2-hydroxy-4-butoxyphenyl]-6-(2,4-dibutoxyphenyl)-1,3,5-triazine UV absorbers, etc. a light stabilizer (HALS) such as a compound having a 2,2,6,6-tetramethylpiperidine skeleton, 201009397 1,2,2,6,6-pentamethyl-4-piperidine skeleton, for example, hydrazine, Ν·,Ν",Ν·"-tetrakis (4,6-bis(butyl-(N-methyl-2,2,6,6-tetramethylpiperidin-4-yl))amino) Pyrazin-2-yl)-4,7-diazadecane-l,l-diamine, decanedioic acid bis(2,2,6,6-tetramethyl-1-octyloxy-4 -piperidinyloxy) bis(1,2,2,6,6-pentamethyl-4-piperidinyl)[[3,5-bis(1,1-dimethylethyl)-4 -hydroxyphenyl]methyl]butylmalonate, bis(1,2,2,6,6-pentamethyl-4-piperidyl)sebacate, corresponding to such dicarboxylates C4_2Q alkanedicarboxylate (malonic acid, adipic acid, etc.) or an aromatic hydrocarbon dicarboxylate (phthalate, etc.). The thermal stabilizer is, for example, a phosphite stabilizer (tris(bromoalkylphenyl) phosphite such as tris(2,4-di-t-butylphenyl)phosphite, bis(alkylaryl) Phosphate stabilizer (or phosphate) such as pentaerythritol diphosphite or the like, a sulfur-based heat stabilizer, a hydroxylamine-based heat stabilizer, and the like. These stabilizers (e.g., light stabilizers, etc.) may be of a low molecular weight type or a high molecular weight type. The stabilizer may be used singly or in combination of two or more components (for example, a combination of an antioxidant and a UV absorber, a combination of an ultraviolet absorber and a light stabilizer, a combination of an antioxidant and a UV absorber and a light stabilizer) use. The amount of each stabilizer used is 0.01 to 2.5 parts by weight, preferably 0. 03 to 2 parts by weight, based on 100 parts by weight of the resin component constituting the anisotropic diffusion layer (for example, 0.05 to 1.5 parts by weight). It is more preferably 0.07 to 1 part by weight (e.g., 〇·1 to 〇·7 parts by weight), and is usually 0.07 to 0.5 part by weight (e.g., 0.1 to 0.3 part by weight). More specifically, the antioxidant is 0.05 to 1 part by weight (e.g., 0.08 to 0.3 part by weight) based on 100 parts by weight of the resin component, and the ultraviolet absorber is 0.1 to 2 parts by weight based on 1 part by weight of the resin component. (For example, 0.2 to 0.7 part by weight), the light stabilizer -23 to 201009397 is 0.03 to 0.5 part by weight (e.g., 0.05 to 0 to 25 parts by weight) based on 100 parts by weight of the resin component. The total amount of the stabilizer is 5% to 3 parts by weight based on 100 parts by weight of the resin component (e.g., 〇·ΐ~2 parts by weight), preferably 〇.1 to 1 part by weight. When a plurality of stabilizers are used, the ratio of the first stabilizer (for example, the antioxidant layer) to the second stabilizer (for example, the ultraviolet absorber) may be selected from the former/the latter (weight ratio) = 95/5 to 10/90. (For example, in the range of 90/10 to 30/70), when a composite system of a combination of a polycarbonate resin and a polypropylene resin is melt-extruded or composited, a part of the extrudate gradually becomes an eye-like form. The ground is deposited on the lip (especially the wall portion adjacent to the opening of the lip), and the deposit grows to come into contact with the molten sheet extruded from the lip to form a non-uniform sheet. Therefore, it is not possible to continuously manufacture sheets and films of uniform sentences. In this case, if the stabilizer (for example, an antioxidant and/or an ultraviolet absorber) is contained, it is especially selected from at least one of an antioxidant and an ultraviolet absorber (separate antioxidant, ultraviolet absorber alone, antioxidant, and ultraviolet absorption) In the case of the agent, the formation of the deposit and the growth thereof can be remarkably prevented, and a uniform sheet and film can be continuously produced. In addition, the antioxidant and/or the ultraviolet absorber, in particular, at least the antioxidant may be contained in the anisotropic diffusion layer in contact with the lip, and when the transparent resin layer is laminated on the anisotropic diffusion layer, it may be contained in the laminate. The transparent resin layer of the tropic diffusion layer may be contained in the anisotropic diffusion layer and the transparent resin layer. The anisotropic diffusion layer is usually contained in at least one selected from the group consisting of an antioxidant and an ultraviolet absorber. In the anisotropic diffusion layer, the ratio of the average length L of the long axis of the dispersed phase to the average length W of the short axis (average aspect ratio, L/W) is greater than I, 201009397 and the long axis direction of the dispersed phase is aligned therein. One direction. The dispersed phase can be fibrous. The aspect ratio of the dispersed phase is usually greater than 1 (for example, 2 to 20,000), for example, 3 to 20,000 (for example, 5 to 15,000), preferably 10 to 12,000 (for example, 50 to 10,000), and more preferably 100 to 9000 (for example, 200 to 8,000). ). In particular, in order to increase the anisotropy, the aspect ratio of the dispersed phase is 50 to 20000 (e.g., 100 to 15,000), more preferably 1,000 to 10,000 (e.g., 3000 to 8000). The larger the aspect ratio of such dispersed phase particles, the more the light scattering property of anisotropy can be improved. Such dispersed phase particles may be a football-type shape (rotational elliptical shape, etc.), a twin shape, a square shape, or the like. In the anisotropic diffusion layer, the long axis direction of the dispersed phase is oriented in a predetermined direction of the film, i.e., the X-axis direction (accepting direction or mechanical direction) forms a particulate dispersed phase. In particular, the present invention can exhibit high anisotropy by increasing the aspect ratio of the dispersed phase particles of the anisotropic diffusion layer, and can efficiently generate and collect the generated anisotropic diffused light at the ankle. Since it is in the front direction, even if it is an anisotropic diffusion layer after thin meat, the uniformity of brightness can be improved. The average length L of the major axis of the dispersed phase may be selected, for example, in the range of 0.1 to 2 000 μm, such as 1 to 1 500 μm, preferably 1 to 1200 μm (for example, 1 · 5 to 1 ΟΟΟ μηη), and particularly preferably 2 to 900 μm ( For example, 5 to 800 μm), usually 100 to ΙΟΟΟμηη (for example, 300 to 800 μm). Further, the average length W of the minor axis of the dispersed phase may be selected, for example, from the range of 0.01 to ΙΟμηη, for example, 〇_〇ι~1μηη, preferably 0.02 to 0·8 μηη, more preferably 0.03 to 0.7 μίη (especially 0.05~) 〇.5μιη) 配 The alignment coefficient of the dispersed phase particles as the alignment degree is, for example, 〇·3 4 or more (0.34 to 1), preferably 〇.4 to 1 (for example, 0.5 to 1), and more preferably ojm. Dispersion -25- 201009397 The higher the alignment coefficient of phase particles, the higher the anisotropy of scattered light. The alignment coefficient is calculated according to the following formula 1. [Number 1] Alignment coefficient = (3 <cos20>-1)/2 _._(1) (In the formula 1, the lanthanum indicates the angle between the long axis of the dispersed phase and the X axis of the film, (when the major axis is parallel to the X axis, θ = ο°), <c〇s2e> represents the average of c〇s20 calculated for each dispersed phase particle, expressed by the following formula 2) [Number 2] <cos2e>=S n(e). Cos20. De ". (2) In the formula 2, n(0) is a ratio (weight) of the dispersed phase particles having an angle of 0 in the fully dispersed phase particles. The anisotropic diffusion layer may have directivity of diffused light. That is, the directivity refers to an angle in which the scattering intensity is extremely large among the directions in which the scattering is strong in the anisotropic diffused light. When the diffused light has directivity, in the measuring apparatus of Fig. 5 to be described later, when the diffused light intensity F is plotted against the diffusion angle ,, the graph curve is in the range of the specific diffusion angle ( (the angle region not including θ = 0°). Has a great or shoulder (especially extremely reciprocal points). When the anisotropic light-diffusing film is imparted to the directivity, the average length of the long axis of the dispersed phase particles is, for example, 10 to ΙΟΟμηη, preferably 20 to 60 μm. The thickness of the anisotropic diffusion layer is 3 to 500 μm (for example, 3 to 300 μm), preferably 5 to 200 μm (for example, 10 to 200 μm), more preferably 15 to 150 μm (for example, -26 to 201009397 30 to 120 μm). The diffusing layer may be a single layer body in which light is diffused by the directionality of the transmitted light, or a laminated body composed of the anisotropic diffusion layer and the transparent resin layer laminated on at least one surface thereof. Laminate comprising an anisotropic diffusion layer A transparent resin layer may be laminated on one or both sides of the anisotropic diffusion layer. The transparent resin layer is a resin having high transparency, and includes, for example, a thermoplastic resin [olefin resin, cyclic olefin resin, halogen-containing resin (including Φ fluorine resin), vinyl alcohol resin, fatty acid vinyl ester resin, ( Methyl) acrylic resin, styrene resin, polyester resin, polyamine resin, polycarbonate resin, thermoplastic polyurethane resin, polycrystalline resin (polyether mill, poly Maple, etc., polyphenylene ether resin (polymer of 2,6-xylenol, etc.), cellulose ester, and decyl alkane resin (polydimethyl siloxane, polymethyl phenyl siloxane, etc.) ), an elastomer (a nitrile-butadiene copolymer, an acrylic rubber, a urethane rubber, a rubber thermoplastic elastomer such as a silicone rubber), etc., and a thermosetting resin (epoxy resin, no Saturated polyester tree • fat, diallyl phthalate resin, decane resin, etc.). A preferred resin-based thermoplastic resin. The resin having high transparency may be a non-crystalline resin. Examples of the olefin-based resin include a polypropylene resin, a copolymer of an a-C 2-6 olefin and a copolymerizable monomer (ethylene-vinyl acetate copolymer, ethylene-vinyl alcohol copolymer, ethylene-(meth) acrylate copolymer, a copolymer of an ethylene-(meth)acrylic acid copolymer or a salt thereof (for example, an ionomer resin), etc. The cyclic olefin resin is, for example, a cyclic olefin (norbornene, dicyclopentadiene, etc.) a polymer or a copolymer (for example, a stereocyclic straight tricyclodecane or the like having a alicyclic hydrocarbon group, etc.), a copolymer of the above cyclic olefin and a copolymerizable monomer (ethylene-lowering) In addition, the polypropylene resin constituting the transparent resin layer and the type, molecular weight, distribution, and melting of the polypropylene resin constituting the anisotropic diffusion layer are used. The flow rate may vary, but may be the same or at least a part of the copolymerization synthesis into a common system (or the same). The halogen-containing resin is, for example, a halogenated vinyl resin (polyvinyl chloride, polyvinyl fluoride, etc.). a homopolymer of a halogen-containing monomer, a copolymer of a halogen-containing monomer such as a vinyl chloride-vinyl acetate copolymer or a vinyl chloride-(meth)acrylate copolymer, and a copolymerizable monomer, etc. a halogenated vinyl resin (a copolymer of a halogen-containing vinylidene monomer such as a vinylidene chloride-(meth)acrylate copolymer and the like, etc.), etc. The aliphatic vinyl ester resin is, for example, a vinyl ester series. a homopolymer or copolymer (polyvinyl acetate, etc.), a copolymer of a vinyl ester monomer and a copolymerizable monomer (vinyl acetate-ethylene copolymer, vinyl acetate-vinyl chloride copolymer, vinyl acetate) An ester-(meth)acrylate copolymer or the like) or a derivative thereof. The derivative of the aliphatic vinyl ester resin includes polyvinyl alcohol, an ethylene-vinyl alcohol copolymer, a polyvinyl acetal resin, and the like. As the acrylic resin, a homopolymer or a copolymer of a (meth)acrylic monomer, a copolymer of a (meth)acrylic monomer and a copolymerizable monomer can be used. For example, a (meth)acrylic monomer (meth)acrylic acid; (methyl) (meth)acrylic acid C, _ i decyl ester such as methyl acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2 · ethylhexyl (meth) acrylate; (methyl) Hydroxyalkyl acrylate: glycidyl (meth)acrylate; (meth)acrylonitrile-28-201009397: (meth)acrylic phenol having an alicyclic hydrocarbon group such as tricyclodecane, etc. Copolymerizable monomer There are styrene-based monomers, etc. These monomers may be used singly or in combination of two or more. The (meth)acrylic resin is, for example, poly(meth)acrylate or methacrylic acid such as polymethyl methacrylate. Methyl ester·(meth)acrylic acid copolymer, methyl methacrylate-(meth)acrylate copolymer cresyl methacrylate-acrylate-(meth)acrylic acid copolymer, methyl (meth)acrylate- A styrene copolymer (MS resin, etc.) or the like. The preferred (meth)acrylic resin is, for example, a methyl methacrylate-based resin containing methyl methacrylate as a main component (about 50 to 100% by weight, preferably 70 to 100% by weight). The styrene resin includes, for example, a homopolymer or a copolymer of a styrene monomer (polystyrene, styrene-α-methylstyrene copolymer, styrene-vinyltoluene copolymer, etc.), styrene single A copolymer of a body and another polymerizable monomer ((meth)acrylic monomer, maleic anhydride, maleic imine monomer, diene, etc.). The styrene copolymer is, for example, a styrene-acrylonitrile copolymer (AS resin), a copolymer of styrene and a (meth)acrylic monomer [styrene-methyl methacrylate copolymer, styrene-methyl group). Methyl acrylate-(meth) acrylate copolymer, styrene-(meth) acrylate copolymer of styrene-methyl methacrylate-(meth)acrylic acid copolymer, etc., styrene-maleic anhydride Copolymers, etc. A preferred styrene-based resin comprises: a copolymer of polystyrene, styrene and a (meth)acrylic monomer; a styrene-methyl methacrylate copolymer or the like having styrene and methyl methacrylate as a main component Copolymer of component], AS resin, styrene-butadiene block copolymer, and the like. -29- 201009397 Polyester-based resin is, for example, an aromatic polyester (polyethylene terephthalate or polybutylene terephthalate) Formic acid C2. a homopolyester of alkane diester or the like, a c2_4 alkane diester unit of an aromatic acid (poly(terephthalic acid) c2-4 alkyl diester and/or polynaphthalene dicarboxylic acid c2. The 4-alkyl diester unit is a main component (e.g., 50% by mole or more, preferably 7 5 to 1 0% by mole %, more preferably 80 to 100 % by mole) of a copolyester or the like). The copolyester, for example, comprises: a part of the C^4 alkanediol with a polyoxy group C2. Copolymerization of 4-alkanediol, C6_10 alkanediol, alicyclic diol (cyclohexanedimethanol, hydrogenated bisphenol A, etc.), bisphenol A, bisphenol A-alkylene oxide adduct, etc. A part of an ester or an aromatic dicarboxylic acid is a copolyester substituted with an aliphatic C6-12 dicarboxylic acid such as an asymmetric aromatic dicarboxylic acid such as phthalic acid or isophthalic acid or adipic acid. . The polyester resin includes a polyarylate resin, a homopolyester of an aliphatic dicarboxylic acid such as adipic acid, or a homopolymer or copolymer of a lactone such as ε-caprolactone. The preferred polyester resin is usually amorphous such as an amorphous copolyester (for example, an aromatic acid C2-4 alkylene glycol alkyl ester copolyester). The polyamine-based resin is, for example, an aliphatic polyamine or a dicarboxylic acid such as polyamine 6, polyamine 66, polyamine 610, polyamine 612, polyamine 11, polyamine 12 or the like (for example, At least one component of terephthalic acid, isophthalic acid, adipic acid, etc. and a diamine (for example, hexamethylenediamine or m-xylylenediamine) is an aromatic compound of polyamine (xylylenediamine) An aromatic polyamine such as a diester (MXD-6) or the like). The polyamine resin may be a homopolymer or a copolymer of a lactone such as ε-caprolactone, and is not limited to the homopolyamine or the copolymerized guanamine phthalate. For example, the same resin as described above may be used. The polycarbonate-based resin constituting the transparent -30-201009397 resin layer may be different from the type, molecular weight, melt flow rate, and the like of the polycarbonate-based resin constituting the light-diffusing layer, and the nitrogen may be the same system in which the same kind or skeleton is used (or In the case of the same resin, the adhesion to the light diffusion layer may be improved. The polycarbonate resin is preferably a polycarbonate resin based on bis(hydroxyaryl) Cm alkane such as bisphenol A, and a cellulose ester such as an aliphatic organic acid ester (cellulose diacetate, three). Cellulose acetate such as cellulose acetate; cellulose propionate, cellulose butyrate, cellulose acetate propionate, cellulose acetate butyrate, etc. C! _6 organic acid ester, etc.), aromatic organic The acid ester (C7_, 2 aromatic carboxylic acid ester such as cellulose phthalate or cellulose benzoate) may be a mixed acid ester such as acetic acid-cellulose nitrate. The preferred component constituting the transparent resin layer contains an olefin resin, a (meth)acrylic resin, a styrene resin, a polyester resin, a polyamide resin, a polycarbonate resin, or the like. A preferred transparent resin layer may be composed of a polycarbonate resin. The resin constituting the transparent resin layer may be the same or different resin as the resin constituting the continuous phase and/or the dispersed phase of the anisotropic diffusion layer, as long as the adhesion or mechanical properties are not impaired, and it is usually preferred and continuous. Resin with the same or common (or the same system) resin. The transparent resin constituting the transparent resin layer is preferably a heat resistant resin (a resin having a high glass transition temperature or a high melting point) or a crystalline resin in order to improve heat resistance or blocking resistance. The glass transition temperature or melting point of the resin constituting the transparent resin layer is about 130 to 280 ° C, preferably 140 to 270 ° C, more preferably 150 to 260 ° C ° -31 - 201009397. Further, the transparent resin layer may contain Conventional additives, for example, stabilizers (antioxidants, ultraviolet absorbers, heat stabilizers, light stabilizers, etc.), plasticizers, antistatic agents, flame retardants, and the like. In particular, the transparent resin layer contains a stabilizer (antioxidant, ultraviolet absorber, light stabilizer), preferably at least one component selected from the group consisting of an ultraviolet absorber and a light stabilizer (a separate ultraviolet absorber, alone light stabilizer) The agent, the ultraviolet absorber and the light stabilizer are particularly preferably composed of a resin layer of a UV absorber and a light stabilizer. The stabilizer may be the same as the above, and the amount of each stabilizer and the total amount of the stabilizer may be selected from the resin constituting the anisotropic diffusion layer with respect to 100 parts by weight of the resin component constituting the transparent resin layer. The ratio of the components is the same. Further, when the ultraviolet absorber and the light stabilizer are used, the ratio of the two may be selected from the range of the former/the latter (weight ratio) = 95/5 to 5 0/50 (for example, 90/10 to 70/30). The thickness of each of the transparent resin layers may be the same as that of the anisotropic diffusion layer. For example, when the thickness of the anisotropic diffusion layer is about 3 to 300 μm, the thickness of the transparent resin layer may be selected from 3 to 15 μm. The ratio of the thickness of the anisotropic diffusion layer to each of the transparent resin layers, for example, the anisotropic diffusion layer/transparent resin layer = 5/9 5 to 99/1, preferably 30/7 0 to 99/1, more preferably 40 /60~95/5. The thickness of the laminated film is, for example, 6 to 600 μm, preferably 10 to 400 μm, more preferably 20 to 250 μm. Conventionally, a diffusion plate having a thickness of several millimeters has been used, but the present invention does not use such a thick diffusion plate, even An anisotropic diffusion layer of a sheet of several tens of micrometers can also effectively diffuse light and improve the brightness of the display device. In particular, even in the case of a backlight type liquid crystal display device having a tubular light source, the brightness of the display device can be effectively improved. • 32- 201009397 The anisotropic diffusion layer (or the laminate of the anisotropic diffusion layer and the transparent resin layer) is, for example, 50% or more (for example, 50 to 100%) based on the total light transmittance of ns K 73 0 1 Preferably, it is 60% or more (for example, 60 to 1% by weight), and particularly 70 to 95% (for example, 75 to 90%). Further, the haze of the anisotropic diffusion layer (or the laminate of the anisotropic diffusion layer and the transparent resin layer) is 80% or more (for example, 80 to 99. 9%), preferably more than 90% (for example, 90 to 99. 8%), more preferably 93~99. 5% 'especially 95~99%. When the total light transmittance is small, the luminance φ is liable to decrease. When the haze is small, the light cannot be spread evenly, and the display quality is lowered. On the surface of the anisotropic diffusion layer (or the laminate of the anisotropic diffusion layer and the transparent resin layer), surface treatment such as corona discharge treatment can be applied without impeding the range of optical characteristics. As shown in Fig. 1, an example of the anisotropic diffusion layer 17 is composed of a plurality of resins having different refractive indices, and may have a phase separation structure (or island structure) in which the particulate dispersed phase 17b is dispersed in the continuous layer 17a. The single layer structure φ is formed. As shown in Fig. 2, an example of the anisotropic diffusion layer 28 may have a laminated structure in which at least one surface thereof is laminated with a transparent resin layer 29. The laminate system containing such an anisotropic diffusion layer 28 protects the anisotropic diffusion layer 28 by the transparent resin layer 29' to prevent the dispersed phase particles from falling off or adhering, thereby improving the damage resistance or manufacturing stability of the film while improving the film. Strength and usability. As shown in Fig. 3, an example of the anisotropic diffusion layer 37 is composed of a continuous phase 37a composed of a resin and a dispersed phase 37b dispersed in a different shape in the continuous phase 37a. In addition, the anisotropy of light diffusion is in the scattering characteristic F(0) indicating the relationship between the scattering angle -33 - 201009397 0 and the scattered light intensity F, and the scattering characteristic in the X-axis direction of the film is Fx(0), and When the scattering characteristic in the Y-axis direction orthogonal to the X-axis direction is Fy(0), the scattering characteristics Fx(0) and Fy(e) show a pattern in which the light intensity gradually decreases as the scattering angle Θ becomes a wide angle. In the range of scattering angle 0 = 4~30°, the 値 of Fy(0)/Fx(0) is 1. 01 or more, for example 1. 01~2 00, preferably 1. 1 to 150. Also, when the scattering angle is 0 = 18°, the difference between Fy(0)/Fx(0) is 1. 1~400 (for example, 1·1~100), preferably 1. 1~200, more preferably 5~100 (especially 10~80). When an anisotropic diffusion layer having such optical characteristics is used, by arranging with respect to the axial direction of the rod-shaped light source and scattering in the vertical direction, the lamp image recognizable by the rod-shaped light source itself can be suppressed, and the brightness reduction can be suppressed to Minimal. When Fy(e)/Fx(e) and Fy(e)/Fx(e) with a scattering angle of 0 = 18° are too large, although the lamp image can be suppressed, the brightness reduction is large, and the opposite is true. If this is too small, although the brightness/reduction can be suppressed, the lamp image will be found. In order to prepare a film of such scattering characteristics, the selection of the components (especially the resin) constituting the continuous phase and the dispersed phase, the molding conditions, in particular, the extrusion temperature, the draw ratio after forming, and the cooling temperature are important. A film having such light diffusing properties can be obtained by producing a film from the types and conditions described below. Further, the X-axis direction of the anisotropic diffusion layer 37 is usually the long-axis direction of the dispersed phase. Therefore, the X-axis direction of the anisotropic diffusion layer is arranged in a substantially parallel direction with respect to the axial direction (Y-axis direction) of the linear light source of the backlight unit. The X-axis direction of the anisotropic diffusion layer does not have to be completely parallel to the axial direction (Y-axis direction) of the linear light source of the backlight unit, for example, at an angle of -34 - 201009397 15° (for example, ±10°, especially ± Within the range of 5°), it is arranged in the oblique direction. The scattering characteristic F(e) is measured using, for example, the apparatus shown in Fig. 4. This apparatus includes a laser light irradiation device (for example, NIHON KAGAKU ENG NE〇-20MS) 38 for irradiating the anisotropic diffusion layer 37 with laser light, and a detector for measuring the intensity of the laser light transmitted through the anisotropic diffusion layer 37. 39. Then, the laser light is irradiated at an angle (vertical) of 90° with respect to the surface of the anisotropic diffusion layer 37, and the intensity (scattered light intensity) F of the light diffused through the sheet is measured (drawn) with respect to the scattering angle β, Light scattering characteristics can be obtained. The anisotropic diffusion layer can further reduce the dependence of the scattering angle in a predetermined direction when the anisotropy of light scattering is high, so that the angular dependence of the brightness can be further reduced. When the anisotropic diffusion layer is perpendicular to the display surface (90°), when it is 0, it exceeds the angle of 20° with respect to the display surface, and even if the angle is 40° or more, the decrease in brightness can be suppressed. "Isocratic diffusion layer" φ Next, the isotropic diffusion layer is explained. An isotropic diffusion layer produces light in an isotropic manner. In the first aspect, at least two or more light control films are used as the isotropic diffusion layer having an isotropic diffusion layer of 70% or more, and the brightness can be made uniform by multiplying the anisotropic diffusion layer. Not only can the lamp image be suppressed, but also the front brightness can be improved. According to the second aspect, by providing an isotropic diffusion layer on the light control film, the brightness can be made uniform by multiplying the anisotropic diffusion layer, and a lamp image can be suppressed. The isotropic diffusion layer is composed of a polymer resin and particles added as necessary when the surface has an irregular fine uneven shape on the surface. As the polymer resin which can be used for the isotropic diffusion layer, a resin excellent in optical transparency can be used. For example, there are a polyester resin, an acrylic resin, an acrylic urethane resin, a polyester acrylate resin, a polyurethane acrylate resin, an epoxy acrylate resin, and an amine group. An acid ester resin, an epoxy resin, a polycarbonate resin, a cellulose resin, an acetal resin, a polyethylene resin, a polystyrene resin, a polyamine resin, a polyimide resin, A thermoplastic resin such as a melamine resin, a phenol resin or a polyoxyxylene resin, a thermosetting resin, or a free radiation curable resin. Among these, an acrylic resin excellent in light resistance and optical properties is preferably used. As the particles, for example, inorganic fine particles such as cerium oxide, clay, talc, calcium carbonate, calcium sulfate, barium sulfate, aluminum silicate, titanium oxide, synthetic zeolite, alumina, montmorillonite, etc., styrene resin, urethane can be used. Organic fine particles composed of an ester resin, a guanamine resin, a polyoxyxylene resin, an acrylic resin, or the like. The particles may be used alone or in combination of plural kinds. The content ratio of the particles to the polymer resin depends on the average particle diameter of the particles to be used or the thickness of the isotropic diffusion layer, and cannot be considered in any case, and when the balance of the isotropic diffusivity and the brightness is considered, The haze to be described later is preferably 60% or more in the second aspect, and is preferably 70% or more in the first aspect, and is preferably 50 parts by weight or more and 250 parts by weight based on 1 part by weight of the polymer resin. Hereinafter, it is more preferably 100 parts by weight or more and 250 parts by weight or less. The average particle diameter of the particles is preferably in the range of 1 to 40 μm in consideration of the balance of the isotropic diffusivity and the brightness of -36 to 201009397. The thickness of the isotropic light-diffusing layer is diffused in the same direction, and the haze is hereinafter preferably 60% or more from the second viewpoint, and 70% or more from the first viewpoint, and preferably 7 to 60 μm. More preferably, it is a 20~35μιη 〇 isomeric diffusion layer in addition to the above polymer resin or particles, a photopolymerization initiator, a photopolymerization promoter, a flat agent may also be added. An additive such as an antifoaming agent such as ** surfactant, oxidation inhibitor, or ultraviolet absorber. The isotropic diffusion layer may be formed by laminating the isotropic diffusion layer on a support. As the support, a conventionally known support such as a plate or a film made of glass or plastic can be used. Specifically, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polycarbonate, polypropylene, polyethylene, polyacrylate, acrylic acid, fluorenyl group can be used. A plastic film or sheet of cellulose, polyvinylidene chloride or the like is preferably subjected to elongation processing, particularly biaxial stretching, from the viewpoint of dimensional stability. The thickness of the support φ body is preferably 10 to 400 μm. The isotropic diffusion layer of the first aspect has a haze of 70% or more, and the haze of the isotropic diffusion layer of the second aspect is 60% or more. A light control film having at least two or more isotropic diffusion layers having a haze of 70% or more, or a light control film having an isotropic diffusion layer having a haze of 60% or more and a lens layer to be described later is incorporated in the backlight The device does not generate a lamp image. The backlight device such as a backlight type liquid crystal display device can be made thinner and brighter. From the viewpoint of improving the brightness and more effectively suppressing the generation of the lamp image, the haze of the two viewpoints is preferably 80% or more, and particularly preferably 90% or more. -37- 201009397 The light control film of the first aspect is composed of at least two or more isotropic diffusion layers, but the haze of the two or more isotropic diffusion layers is preferably 90% or more. Good is over 95%. When the haze when two or more isotropic diffusion layers are overlapped is set to 90% or more, when light passes through two or more isotropic diffusion layers, the light is inside and at the interface of the isotropic diffusion layer. The component that refracts in the front direction increases, and has diffusivity in the same direction, which improves the brightness in the front direction. <<Lens Layer>> Next, the lens layer of the second aspect will be described. The lens layer is provided with a structure in which a plurality of structures having a geometrical shape in cross section are arranged. The aforementioned geometric shape means, for example, a triangular shape or a polygonal shape, a table shape, a semicircular shape, or the like, and the above-mentioned structure is, for example, a triangular pyramid, a pyramid, a truncated cone, a triangular prism, a corner post, a cylinder, a hemispherical shape or the like. Further, the foregoing structures may be formed in a plurality of irregularities or independently, and are usually arranged in a regular arrangement, for example, juxtaposed to each other, particularly in the form of adjacent ones, and the regular arrangement is better. In a preferred aspect of the lens layer, for example, a structure having a plurality of structures having a triangular cross section (稜鏡 unit) is juxtaposed to each other, and in particular, a lens which is juxtaposed in the form of adjacent ones and which is regularly arranged. The layer is better from the viewpoint of improving the front brightness. The triangular shape may be an equilateral triangle shape, but is preferably a equilateral triangle, particularly a second side having an apex angle of 50 to 120° (preferably 60 to 110°, more preferably 70 to 100°). Triangle shape. In the section, the apex angle of the triangular shape is 90° ± 10°, and particularly preferably 90° ± 5°. -38- 201009397 The distance between the prism units may be selected, for example, from 5 to 100 μm, usually from 10 to 80 μm, preferably from 20 to 60 μm, more preferably from 30 to 50 μm. The height of the aforementioned unit may be selected, for example, in the range of 1 to 50 μm, usually 5 to 45 μm, preferably 10 to 40 μm (for example, 15 to 30 μm), more preferably 1 to 5 μπ μm. The above-mentioned crotch portion (structural portion) may be a member having a crotch portion in a region (base region) which is a base of the crotch portion, or may be a crotch portion having only a Φ non-base region. The height (thickness) of the base region is, for example, 0 to 30 μm (for example, 0. 1 to 30 μm)) is preferably 1 to 20 μm, more preferably 3 to 1 5 μπι. The material constituting the lens layer is, for example, a polymer resin. The polymer resin is exemplified by a thermosetting resin, a thermoplastic resin, and an ionizing radiation-curable resin. Examples of the thermosetting resin include a polyoxynenoid resin, a phenol resin, a urea resin, a melamine resin, a furan resin, an unsaturated polyester resin, an epoxy resin, and a diallylphthalic acid. An ester resin, a guanamine resin, a ketone resin, an amino alkyd resin, a polyurethane resin, an acrylic resin, a polycarbonate resin, or the like. These may be used singly, but in order to further improve the crosslinkability and the hardness of the crosslinked hard coat film, it is preferred to add a hardener. The hardener is used, for example, in combination with a suitable resin such as a polyisocyanate, an amine resin, an epoxy resin or a carboxylic acid. The thermoplastic resin is, for example, AB S resin, norbornene resin, polyoxyn resin, nylon resin, polyacetal resin, polycarbonate tree-39-201009397 grease, modified polyphenylene ether resin, polypair Dibutyl phthalate, polyethylene terephthalate, maple resin, quinone imide resin, fluorine resin, styrene resin, acrylic resin, vinyl chloride resin, vinyl acetate resin, Ethyl chloride-ethylene acetate copolymer resin, polyester resin, urethane resin, nylon resin, rubber resin, polyvinyl ether, polyethyl alcohol, polyethylene glycol condensate, For example, a photopolymerizable prepolymer or a photopolymerizable monomer which is crosslinked and hardened by irradiation with free radiation can be used for the ruthenium radiation-hardening type resin such as polyethylene. The photopolymerizable prepolymer is particularly preferably an acrylic prepolymer having a three-dimensional network structure by crosslinking and solidifying with two or more of the above-mentioned monomers. The acrylic prepolymer is, for example, a polyurethane acrylate, a polyester acrylate, a poly epoxy acrylate, a melamine acrylate, a polyfluoroalkyl acrylate, a polyoxy acrylate, etc., in combination with a mold or a base. The type and use of the material are appropriately selected. Further, as the photopolymerizable monomer, for example, a monofunctional acrylic acid such as 2-ethylhexyl acrylate, 2-ethyl propylene vinegar, 2-hydroxypropyl acrylate or butoxyethyl acrylate may be used. Monomer, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, diethylene glycol diacrylate, polyethylene glycol diacrylate, hydroxytrimethyl acetate neopentyl glycol One or two or more kinds of polyfunctional acrylic monomers such as a bifunctional acrylic monomer such as acrylate or dipentaerythritol hexaacrylate, trimethylpropane triacrylate or pentaerythritol triacrylate. These photopolymerizable prepolymers or photopolymerizable monomers can be used alone in the range of -40 to 201009397. However, in order to improve various properties such as crosslinking hardenability or viscosity adjustment, it is preferred to use them in combination. When the functional layer is cured by ultraviolet irradiation, it is preferably an additive such as a photopolymerization initiator or a photopolymerization accelerator, in addition to the photopolymerizable prepolymer and the photopolymerizable monomer. The photopolymerization initiators are, for example, acetophenone, benzophenone, minomethanone, benzoin, benzyl methyl ketal, benzamidine benzoate, α-decyloxy decyl ester, thia Anthrone and the like. The photopolymerization accelerator reduces the polymerization barrier by oxygen in the air during hardening, and can improve the curing speed, for example, isoamyl dimethyl-dimethylaminobenzoate, ethyl hydrazine-dimethylaminobenzoate, and the like. . A lens layer can be formed on the support. The support may be the same as those listed in the above-described isotropic diffusion layer. In the long-axis direction of the particulate dispersed phase of the anisotropic diffusion layer, the arrangement direction (or arrangement direction) of the plural units is not particularly limited, and may be, for example, a direction in which the long-axis direction of the dispersed phase is intersected ( The direction of the intersection, the direction of the intersection with the oblique direction). For example, the direction of the major axis of the dispersed phase of the particles and the direction of arrangement of the unit of 稜鏡 (the ridge line or the direction of the long axis) may be, for example, in the range of 15° (preferably ±10°, more preferably ±5°). The upper side may be substantially orthogonal (crossover) in the same direction (substantially juxtaposed), for example, ±15° (preferably ±10°, more preferably ±5°). Preferably, the major axis direction of the particulate disperse phase is parallel to the direction in which the unit of the crucible is extended (the ridge line or the long axis direction of the triangular columnar column). When the long-axis direction of the dispersed phase of the particles is approximately parallel to the direction in which the 稜鏡 unit is extended, the -41 - 201009397 light collecting effect on the front side can be improved. Further, when the long-axis direction of the dispersed phase of the particles is approximately orthogonal to the direction in which the unit of the yttrium is extended, the effect of suppressing the bright line or the dark line can be suppressed. The lens layer having the structure portion composed of such a plurality of units can diffuse the diffused light diffused in the opposite direction by the anisotropic diffusion layer, and the luminance distribution can be averaged. Therefore, the brightness in the front direction is improved, and at the same time, the generation of a lamp image can be suppressed to improve the display quality. As shown in FIG. 5, the light control film according to the first aspect of the invention includes an anisotropic diffusion layer 47 in which a transparent resin layer 49 is formed on both surfaces, and two isotropic diffusion layers 44 formed on the support 45. . The anisotropic diffusion layer 47 is formed of a thermoplastic resin having a refractive index different from that of the continuous phase (matrix) 47a formed of the thermoplastic resin and the thermoplastic resin of the continuous phase 47a, and is aligned with the continuous phase 47a. The dispersed dispersed phase 47b is formed in a predetermined direction, and the dispersed phase 47b is formed into a slender shape. In other words, the major axis of the particulate dispersed phase 47b is aligned in the longitudinal direction of the anisotropic diffusion layer 47. Further, in this example, the continuous phase (matrix) 47a is formed of a resin having high light transmittance, transparency, and heat resistance, for example, a polycarbonate resin, and the particulate dispersed phase 47b is, for example, high in heat resistance. The olefin resin is formed, for example, of a polypropylene resin (a polypropylene resin using a metallocene catalyst). Further, the transparent resin layer 49 is formed of a resin having high transparency and heat resistance, for example, a polycarbonate resin. As shown in Fig. 6, the light control film according to another embodiment of the first aspect is not required to form a transparent resin layer, and includes an anisotropic diffusion layer 47 and two sheets each having a continuous phase 47a and a particulate phase -42 - 201009397 bulk phase 47b. An isotropic diffusion layer 44. As shown in FIG. 7, the light control film of the embodiment of the second aspect includes an anisotropic diffusion layer 47 in which a transparent resin layer 49 is formed on both surfaces, an isotropic diffusion layer 44 formed on the support 45, and a lens. Layer 46. The lens layer 46 has a base region. The anisotropic diffusion layer 47 is formed of a thermoplastic resin having a refractive index different from that of the continuous phase (matrix) 47a formed of the thermoplastic resin and the thermoplastic resin of the continuous phase 47a, and the alignment φ is in the continuous phase 47a. In the predetermined direction, the dispersed particulate dispersed phase 47b is formed, and the particulate dispersed phase 47b is formed into an elongated shape. In other words, the major axis of the particulate dispersed phase 47b is oriented in the longitudinal direction of the anisotropic diffusion layer 47. Further, in this example, the continuous phase (matrix) 47a is formed of a resin having high light transmittance, transparency, and heat resistance, for example, a polycarbonate resin, and the particulate dispersed phase 47b is, for example, high in heat resistance. The olefin resin is formed, for example, of a polypropylene resin (a polypropylene resin using a metallocene catalyst). Further, the transparent resin layer 49 is formed of a resin having a high transparency and heat resistance, such as a polycarbonate resin. The lens layer 46 is formed by a unit 46a of a plurality of cross-sectional triangular shapes. In other words, each unit 46a is adjacent to each other, and the ridge line of each unit 46a extends along the long axis direction of the particulate dispersed phase 47b to form an array. As shown in Fig. 8, the second viewpoint is The light control film of the other embodiment is not required to form a transparent resin layer, and includes an anisotropic diffusion layer 47 including a continuous phase 47a and a particulate dispersed phase 47b, an isotropic diffusion layer 44, and a lens layer 46. This lens layer 46 does not have a base region. -43- 201009397 When such a light control film is used, diffusion is generated in the opposite direction by the anisotropic diffusion layer, and the diffused light diffused by the isotropic diffusion layer is concentrated in the front direction, thereby reducing the linear light source ( The brightness directly above the fluorescent tube, etc., averages the brightness distribution. Therefore, the brightness in the front direction is increased, and the generation of a lamp image can be suppressed, and the display quality can be improved. The light control film of the first aspect is composed of at least two or more isotropic diffusion layers and an anisotropic diffusion layer. By providing at least two or more isotropic diffusion layers and anisotropic diffusion layers, the light from the linear light source can be diffused in the opposite direction through the anisotropic diffusion layer, and the brightness is uniformized. The above-mentioned isotropic diffusion layer allows light to be diffused in the same direction, and the brightness can be more uniform. Thereby, the directivity of the light can be adjusted, and a lamp image is not generated, and the front brightness can be improved. In particular, the light control film is configured in the order of the anisotropic diffusion layer and the two isotropic diffusion layers, and the isotropic diffusion layer is placed on the light exit surface side, and the lamp image can be significantly suppressed. Image) is generated to increase the front brightness. The light control film of the second aspect is composed of at least a lens layer, an isotropic diffusion layer having a haze of 60% or more, and an anisotropic diffusion layer. However, the lens layer of the light control film is different from that of the lens layer. The directional diffusion layer is disposed closer to the light exit surface side. The lens layer of the light control film is disposed closer to the light exit surface than the anisotropic diffusion layer, whereby the light of the linear light source is diffused in the opposite direction through the anisotropic diffusion layer, and the brightness distribution can be uniform. . Further, since the light-emitting surface side of the anisotropic diffusion layer is provided with a lens layer, the diffused light emitted from the anisotropic diffusion layer is collected by the lens layer in the front direction. Therefore, the directivity of the light can be adjusted, and the lamp image (lamp 201009397 image) is not generated, and a high front brightness can be achieved. In particular, the light control film is formed in the order of the anisotropic diffusion layer, the isotropic diffusion layer, and the lens layer, and the lens layer is placed on the light exit surface side, and the lamp image can be significantly eliminated. Achieve high frontal brightness. The anisotropic diffusion layer of the light control film does not necessarily need to form a transparent resin layer. The transparent resin layer does not have to be formed on both surfaces of the anisotropic diffusion layer, and may be formed on at least one side of the anisotropic diffusion layer. The anisotropic diffusion layer of the φ light control film and at least two or more isotropic diffusion layers (first viewpoint), or the anisotropic diffusion layer, the isotropic diffusion layer, and the lens layer (second viewpoint) may be respectively dense It is composed of, but the layers are not to be closed, and the voids are preferably formed. When there is a gap between the layers, the difference in refractive index between the layers and the void portion can be effectively utilized, and the lamp image can be eliminated to achieve high front luminance. <<Formation of Structural Member>> Next, an example of a method of forming a member constituting the light control film will be described. First, the anisotropic diffusion layer can be obtained by dispersing a component (a resin component, a quinone component, or the like) constituting the dispersed phase in a resin constituting the continuous phase. In the method for forming an anisotropic diffusion layer, the dispersed phase is usually obtained by deforming a resin component constituting the dispersed phase and aligning it. For example, a component constituting a continuous phase (for example, a polycarbonate resin) and a component constituting a dispersed phase (for example, a polypropylene resin) and, if necessary, a compatibilizing agent, etc., may be subjected to a usual method (for example, melt doping) if necessary. The mixture is legalized, rolled, etc., blended-45-201009397, melt-mixed, extruded from a T-die or a ring die, and subjected to film formation to disperse the dispersed phase. Further, a coating method in which a composition composed of a light-scattering component (for example, a polypropylene-based resin) and a binder resin (for example, a polycarbonate-based resin) is applied onto a base film can be used, or the above-described composition can be laminated. The film is formed by a conventional film forming method such as a layering method, a casting method, or an extrusion molding method. Usually, a film is formed by an extrusion molding method, and an anisotropic diffusion layer is often used. The alignment treatment of the dispersed phase of the anisotropic diffusion layer can be, for example, (1) a method of stretching an extruded sheet while forming a film, (2) a method of uniaxially stretching the extruded sheet, and (3) a combination. The method of the above (1) and the method of the method (2), and the like. Alternatively, the above components may be solution-blended by (4), and formed by a film formation method such as a cast film method. The temperature above the melting point of the resin component (continuous phase resin, dispersed phase resin) of the melting temperature is, for example, 150 to 270 ° C, preferably 200 to 26 Torr, more preferably 230 to 255 °C. In order to achieve moderate anisotropy, it is preferred to stretch the extruded sheet and form the film in the anisotropic diffusion layer or the melt film. In order to exhibit the defined anisotropic light diffusion characteristics, it is important to adjust the draw ratio after extrusion. The draft ratio (draw ratio) is a ratio of the die diameter of the extruder, the type of the resin, the layer structure, and the like, and may be selected from the range of 1.5 to 50 times, not limited to one, and may be selected, for example, from a single layer. The range of 4 to 40 times, preferably 5 to 35 times, more preferably 8 to 30 times (particularly 10 to 25 times), the parameter of the aforementioned anisotropy may be selected from the foregoing range. When the laminate is used, since the anisotropy tends to be higher than that of the single layer, the draw ratio is, for example, 3.5 to 20 times, preferably 4 to 18 times, more preferably 5 to 16 201009397 times (especially 6 to 15 times). ). The cooling temperature by a casting roll or the like, for example, 30 to 10 ° C, preferably 40 to 100 ° C, more preferably 60 to 9 (degree of TC. The anisotropic diffusion layer can be extended (one or two axes) Extending, especially one-axis extension. The stretching ratio of the anisotropic diffusion layer can be selected according to the aspect ratio of the dispersed phase, for example, the stretching ratio in one direction is 1.1 to 10 times, preferably 1.2 to 5 times, more preferably 1.5. When the isotropic diffusion layer is formed on the support, the isotropic diffusion layer is coated with an isotropic diffusion layer in which a material such as the polymer resin or particles is dissolved in an appropriate solvent. The liquid is a conventionally known method, for example, a bar coater, a blend coater, a spin coater, a roll coater, a gravure coater, a flow coater, a die coater, a sprayer, a net Printing or the like is applied to the support and formed by drying. Alternatively, the surface of the isotropic diffusion layer formed on the support may be subjected to, for example, matting, sandblasting, embossing, etc., physically. It is composed of coarsening. When using a support, for example, a polymer tree will be mixed. Alternatively, the composition of the particles may be formed by extrusion molding or the like, or may be formed using a mold. Next, the lens layer of the second aspect may be formed by using a mold complementary to the shape of the desired structural portion. (Structural portion), a method of forming a crotch portion by molding (or molding) a surface of a base sheet of a thermosetting resin or a thermoplastic resin after softening, and transferring the crotch portion by a transfer mold to The translucent base sheet is cured by a method of curing the lens portion when necessary, and when the free radiation curable resin is applied to the translucent base sheet or coated, the projection has a concavo-convex portion corresponding to the prism unit (adjacent V) The groove metal mold of -47-201009397 is formed by forming a crotch portion and curing the lens portion. The presence or absence of the base region of the crotch portion can be adjusted by using a resin composition which becomes a raw material. The light control film of the first aspect is composed of at least two or more isotropic diffusion layers and an anisotropic diffusion layer, and the haze of the isotropic diffusion layer is 70% or more. Combination loan The anisotropic diffusion effect of the anisotropic diffusion layer and the isotropic light diffusion effect of the isotropic diffusion layer can make the brightness uniform. The second viewpoint of the light control film is an anisotropic diffusion layer and an isotropic property. When the diffusion layer and the lens layer are formed, the haze of the isotropic diffusion layer of the light control film is set to 60% or more, and when the lens layer is compared with the anisotropic diffusion layer, it is disposed closer to the light exit surface side. Therefore, by combining the anisotropic diffusion effect of the anisotropic diffusion layer with the lens effect of the lens layer, the brightness height can be made uniform. Therefore, the above light control film can be used for various optical applications. Since the brightness of the surface is uniform, the backlight image can be suppressed from being thinned and the brightness is increased. Therefore, when a display device such as a liquid crystal display device (particularly a backlight device) is used, the display surface is used. The whole can be uniformly illuminated. Therefore, the light control film of the present invention can be used as a constituent member of a backlight device and a display device (for example, a flat display device (planar display device) in which a video display area such as a liquid crystal display device is a flat surface). <<Liquid Crystal Display Device>> Next, an example of a liquid crystal display device using the above-described light control film will be described. -48-201009397 As shown in FIG. 9 and FIG. 10, the liquid crystal display device of one embodiment is provided with a liquid crystal cell in which liquid crystal is sealed. a surface display unit (transmissive liquid crystal display unit, liquid crystal display panel, or the like) 5 to be irradiated, disposed on the back side of the display unit (or panel) 5, and illuminating the backlight unit for the display unit 5 (the present invention The backlight device 13 is configured. The backlight unit 13 includes a linear light source 1 such as a fluorescent discharge tube (cold cathode tube) disposed in the first or lower side of the display unit 5, and a light source φ-shaped light source 1 in the forward direction (display unit) The side is reflected and guided to the reflecting plate 2 for the display unit 5. As shown in FIG. 9 , in the first aspect, the linear light source 1 may be arranged in the order of the front side of the linear light source 1 (not shown) or on the exit surface side of the support plate. (the light-emitting surface side of the backlight unit), and the anisotropic diffusion layer 14 for diffusing light in the opposite direction, and the light-emitting surface side of the anisotropic diffusion layer 14 are emitted from the anisotropic diffusion layer 14 The light generates two isotropic diffusion layers 12 for light diffusion in the same direction. The light source of the linear light source 1 is diffused by the anisotropic diffusion layer 14 or the two isotropic diffusion layers 12 to uniformize the luminance, and the luminance illumination display unit 5 is improved. The support plate is used to protect the transparent plate formed by the anisotropic diffusion layer 14 of the film. Although the prism sheet is not shown, it can be configured for use. As shown in FIG. 1A, in the second aspect, when necessary, the linear light source 1 may be arranged in order: a support plate (not shown) disposed in front of the linear light source 1 and an exit surface of the support plate The side (the light-emitting surface side of the backlight unit) ′, the anisotropic diffusion layer 14 for diffusing light in the opposite direction, and the light-emitting surface side of the anisotropic diffusion layer 14 are provided, and the anisotropic diffusion layer 14 is provided. -49- 201009397 The emitted light forms an isotropic diffusion layer 12 for light diffusion in an equi-directional direction, and a tantalum sheet (lens layer) 4 which is formed by arranging the cross-sectional triangular shape in a predetermined direction. The light of the linear light source 1 is diffused by the anisotropic diffusion layer 14 or the isotropic diffusion layer 12 to uniformize the luminance, and the light is irradiated to the display unit 5 by collecting the light from the front sheet 4 toward the front. The support plate is used to protect the transparent plate formed by the anisotropic diffusion layer 14 of the film. In the two aspects, the surface display unit (liquid crystal display unit) 5 sequentially laminates the first polarizing film 6a, the first glass substrate 7a', the first electrode 8a formed on the glass substrate, and the laminated electrode. The first alignment film 9a, the liquid crystal layer 10, the second alignment film 9b, the second electrode 8b, the color filter 11, the second glass substrate 7b, and the second polarizing film 6b are formed. Such a display device can directly illuminate a surface display unit from the back surface by a linear light source such as a fluorescent discharge tube (cold cathode tube). Therefore, the backlight device using a linear light source (light) is increased in importance in the liquid crystal display device such as a liquid crystal television in recent years, and the importance of the light emitted from the linear light source is generally high. The distribution is not uniform, and the luminance distribution in the direction orthogonal to the axial direction of the linear light source is not uniform. In particular, the linear light source disposed directly under the display unit (liquid crystal display unit) is visible from the display surface side, and a lamp image remains on the display surface. Therefore, even if a linear light source is used, the brightness on the display surface must also be uniform. In particular, since the anisotropic diffusion layer is close to the linear light source, the anisotropic diffusion layer is required to have a long-term stable light diffusibility. Further, when the anisotropic diffusion layer is used for the backlight unit, the brightness of the display surface can be uniformized from -50 to 201009397, and the generation of the lamP image can be suppressed. The light control film of the first aspect is composed of at least two or more isotropic diffusion layers and an anisotropic diffusion layer, and the isotropic diffusion layer has a haze of 70% or more, and thus the anisotropic scattering layer The high anisotropic scattering function and the high isotropic scattering function of the isotropic diffusion layer make the brightness uniform. In the light control film of the second aspect, the haze of the isotropic diffusion layer is 60% or more, and the lens layer is disposed closer to the light exit surface than the anisotropic diffusion layer, so that the anisotropic scattering layer is used. The multiplying effect of the high anisotropic scattering function and the lens function of the functional portion of the lens layer allows the diffused light to be concentrated in the front direction to uniformize the brightness. Thereby, the generation of a lamp image can be suppressed even in a backlight unit that requires thinning and high brightness. In particular, when the light control film of the present invention is formed in the order of the light incident surface side toward the light emitting surface side, in the order of the anisotropic diffusion layer and the two isotropic diffusion layers, the lamp image can be more significantly suppressed ( Lamp image) is generated to achieve high brightness. Further, when the azonic direction of the dispersed phase of the anisotropic diffusion layer is parallel to the long-axis direction of the linear light source, when the anisotropic diffusion layer is disposed, the linear light source is formed by the different light scattering characteristics. The light can be scattered in the vertical direction for the longitudinal direction of the linear light source, the brightness reduction can be minimized, the brightness of the exit surface can be uniformized, and the display surface can be uniformly illuminated. Even if the thickness of the anisotropic diffusion layer is small (e.g., 0.2 mm), the brightness of the display surface of the backlight type liquid crystal display device can be improved. It is possible to achieve uniform brightness without using a diffusing plate which is conventionally required. Therefore, even a large liquid crystal display device of -51 - 201009397 can make the device thinner and can be easily manufactured. In other words, the light control film of the present invention can uniformly illuminate the display surface of a large-area liquid crystal display device with high brightness even if the thickness is thin. In particular, since the continuous phase and the dispersed phase are composed of a predetermined resin, the direct-type backlight unit which is high in heat resistance and which is close to the linear light source and which has a high temperature effect can maintain the light scattering in a predetermined anisotropy for a long period of time. In the liquid crystal display device, the light control film may be sandwiched between the backlight unit and the display unit in an optical path emitted from the exit surface of the backlight unit, and may be laminated on the exit surface by using an adhesive if necessary. The configuration is configured. More specifically, the light control film may be disposed on the exit surface side of the surface light source unit or the incident surface side of the display unit, or may be disposed between the exit surface of the backlight unit and the display unit. Further, the light control film may be used in combination with a ruthenium sheet, a diffusion sheet, a sheet having an improved brightness, a retardation film, a polarizing film, a color filter or the like. In particular, when a diffusion sheet having a haze of less than 60% is used on the exit surface of the light control film, it is possible to prevent glare and widen the viewing angle. Further, in the backlight unit, the linear light source does not need to be located directly under the display unit, and can also be used as an edge light type at the side. At this time, the light source of the linear light source of the side portion is incident from the side surface of the anisotropic diffusion layer, and the surface slightly orthogonal to the side surface (the surface facing the display unit) is light-emitted to illuminate the display unit. The number of the linear light sources is not particularly limited and can be selected in accordance with the size of the display surface. In the edge light type backlight unit, for example, when a point light source such as an LED light source is used, the brightness in the vicinity of the light source is extremely high, and the brightness -52 - 201009397 tends to decrease as the distance from the light source is moved, and the brightness distribution is large. At this time, according to the light control film of the present invention, the light of the light source can be uniformly emitted, and the brightness of the display surface can be made uniform and bright. The X-axis direction of the light control film is usually the long axis direction of the dispersed phase of the anisotropic diffusion layer. Therefore, the light control film has its X-axis direction arranged in a substantially parallel direction with respect to the axial direction (Y-axis direction) of the linear light source of the backlight unit. The X-axis direction of the light control film is not completely parallel with respect to the axial direction (Y-axis direction) of the linear light source of the backlight unit, for example, within an angle of ±15° (for example, ±10°, especially ±5°) It can be arranged in an oblique direction. [Embodiment] [Examples] Hereinafter, the present invention will be more specifically described by way of examples. “Parts” and “%” are weight basis unless otherwise stated. "1. Production of each layer" "1-1. Production of an anisotropic diffusion layer" As a resin composition for a transparent resin layer, a bisphenol A type polycarbonate resin (IUPILON S-2000: Mitsubishi Engineering Plastics Co., Ltd.) was used. A number average molecular weight: 1 8000 to 20 000, and a melt flow rate of 9 to 12 g/10 minutes). As a composition for an anisotropic diffusion layer, a polycarbonate resin (IUPILON S) which is a resin (matrix resin) constituting a continuous phase is used. -2000: Mitsubishi Engineering Plastics Co., Ltd. 92 parts by weight of a polypropylene-based resin as a resin constituting a dispersed phase (WINTECH WFX-4: Japan POLYPRO Corporation, a propylene-based random copolymer using a urethane-53-201009397 catalyst, The melt flow rate was 7 to 10 g/10 min) and 8 parts by weight. The resin composition constituting each layer was mixed, and the multilayer extrusion molding machine was melted by a die at a resin temperature of 250 ° C and a die diameter of 1.3 mm, and coextruded, and the draft ratio (draw ratio) was 7.7. Double, oil temperature adjustment 3 casting rolls, cooled at 80 ° C to produce an anisotropic diffusion layer forming a transparent resin layer on both sides (total thickness: 175 μηι, thickness of transparent resin layer: 35 μιη, anisotropic diffusion layer Thickness: 105 μιη). The anisotropic diffusion layer in which the transparent resin layer was formed on both sides was measured to have a total light transmittance of 89% in accordance with JIS Κ 73 0 1 using a haze meter (NDH-500: Nippon Denshoku Industries Co., Ltd.). Has an anisotropy of 14. When the cross section is observed by a transmission electron microscope (ΤΕΜ), the polypropylene-based resin forms a scatterer (particulate dispersed phase) in the anisotropic diffusion layer, and the shape of the dispersed phase is ellipsoidal (or elongated) The average length of the short axis is 0.20 μιη and the average length of the long axis is 133.3 μιη (aspect ratio 667). <<1-2. Preparation of Isotropic Diffusion Layer>> The following formulation of the isotropic diffusion layer coating liquid is mixed and stirred, and then applied to a polyethylene terephthalate having a thickness of ΙΟΟμηη by a bar coating method. On the support composed of the ethylenediester film (lumirror Τ60: Toray Industries, Inc.), after drying, the thickness after drying was 2 7 μm, and an isotropic diffusion layer A was produced. <Application liquid for isotropic diffusion layer A> 110 parts • Acrylic polyol (ACRYDIC A-837: DIC Corporation, solid content 50%) 201009397 • Isocyanate-based hardener 22 parts (TAKENATE D110N: Mitsui Chemicals polyurethanes (60% solid content) • 110 parts of acrylic resin particles (average particle size: 15 μm, coefficient of variation: 35%) • 200 parts of butyl acetate • 200 parts of methyl ethyl ketone, the coating liquid for the above-mentioned isotropic diffusion layer A was changed. In the same manner as described above, an isotropic diffusion layer was produced in the same manner as described above except that the coating liquid for the isotropic diffusion layer B was adjusted to have a thickness of 12 μm after drying. <Isocratic diffusion layer coating liquid> • 162 parts of acrylic polyol (ACRYDIC A-807: DIC, solid content 50%) • 32 parts of isocyanate curing agent (TAKENATE D110N: Mitsui Chemicals polyurethanes, Solid content: 60%) 55 parts of acrylic resin particles (MX-1000: Nippon Chemical Co., Ltd., average particle size ΙΟμπι) • 15 parts of polyoxynoxide resin particles (tospearl 130: Momentive Performance Materials. Japan, average particle size 3μιη) • 200 parts of butyl acetate • 200 parts of methyl ethyl ketone The coating liquid for the isotropic diffusion layer coating was changed to the coating liquid for the isotropic diffusion layer C of the following formulation, and the thickness after drying was adjusted to 12 Ηηι外, -55- 201009397 The isotropic diffusion layer c is produced in the same manner as described above. <Coating liquid for isotropic diffusion layer C> • 162 parts of acrylic polyol (ACRYDIC A-807: DIC, solid content 50%) • Isocyanate curing agent 32 parts Φ (TAKENATE D110N: Mitsui Chemicals polyurethanes 60% solid content • 1 part of acrylic resin particles (Ganzpearl GM-0605: Ganz Chemical Co., Ltd., average particle size 6μιη) • 200 parts of butyl acetate • 200 parts of methyl ethyl hydrazine The equivalence of the following prescriptions The coating liquid for the diffusion layer D was applied to one side of a support made of a polyester film (Diafoil O 300: Mitsubishi Plastics Co., Ltd.) having a thickness of ΙΟΟμηη, and was 2.7 μm thick, and was irradiated with ultraviolet rays by a high-pressure mercury lamp for 1 to 2 seconds. Isotropic diffusion layer D. ❹ <Coating liquid for isotropic diffusion layer D> 1 part by weight • UV curable acrylic resin (unidic 17-813: DIC company, 80% solid content) • Photopolymerization initiator (IRGACURE 651: CIBA .Japan Company) 1.6 parts • 200 parts of acrylic resin particles (MX-500KS: comprehensive chemical company, average particle size 5μιη) • Propylene glycol monomethyl ether -56- 201009397 "1-3. Production of lens layer" at the top angle 90 ° The lens layer liquid of the following prescription is applied to a mold having a triangular columnar structure of a pitch of 50 μm, and a polyethylene phthalate (Cosmoshine Α 4100: Toyobo Co., Ltd.) having a thickness of 100 μm is applied. Adhesively, a lens layer is formed between the polyethylene terephthalate film and the mold to form a mirror shape with a shape of the die (thickness of the crotch portion (functional portion): 25 μm, thickness of the domain: 5 μm) . <Coating liquid for lens layer> •Acrylic monomer (methyl methacrylate: Wako Pure Chemical Industries, Ltd.) • Polyfunctional acrylic monomer (NK ester Α-ΤΜΡΤ-3ΕΟ: Shin-Nakamura Chemical Industry Co., Ltd.) • Light Polymerization initiator (IRGACURE 184: CIBA. Japan) In addition, in the state in which the lens layer and polyethylene terephthalate are laminated in a thin layer, the polyethylene terephthalate film side is made of silver. After the lamp was irradiated with ultraviolet rays of 600 mJ/cm 2 to harden the functional layer, a lens layer formed on the support was produced. <<2. Production of Light Control Film>> [Example 1] The unit is coated with an ester film, a benzoic acid-filled rib base region, 50 parts, 45 parts, a 5-part film, and a high-pressure water mold stripping-57-201009397. The anisotropic diffusion layer, the isotropic diffusion layer A, and the isotropic diffusion layer A are not closely adhered to each other, and the light control film of the first embodiment is formed by overlapping (the isotropic diffusion layer A becomes the light exit surface side). Configuration in the state). [Example 2] The isotropic diffusion layer A, the anisotropic diffusion layer, and the isotropic diffusion layer A produced as described above were not closely adhered, and the light control film of Example 2 was produced by lamination. [Example 3] The isotropic diffusion layer A, the isotropic diffusion layer A, and the anisotropic diffusion layer prepared as described above were not closely adhered, and the light control film of Example 3 was produced by overlapping (anisotropy) The diffusion layer is disposed in a state of being on the light exit surface side). [Example 4] The anisotropic diffusion layer, the isotropic diffusion layer B, and the isotropic diffusion layer B prepared as described above were not closely adhered to each other, and the light control film of Example 4 was formed by overlapping (isotropy) The diffusion layer B is disposed in a state of being on the light exit surface side). [Example 5] The anisotropic diffusion layer, the isotropic diffusion layer A, and the lens layer produced as described above were not closely adhered, and the light control film of Example 5 was formed by overlapping (the lens layer became the light exit surface side). Configuration under the state). -58-201009397 [Example 6] The isotropic diffusion layer A, the anisotropic diffusion layer, and the lens layer produced as described above were not closely adhered, and the light control film of Example 6 was formed by overlapping (the lens layer was formed). The light is emitted on the side of the surface.) [Example 7] The anisotropic diffusion layer, the lens layer, and the isotropic diffusion layer A produced as described above were not closely adhered, and the light control film of Example 7 was formed by overlapping (the isotropic diffusion layer A was formed). The light is emitted on the side of the surface.) [Example 8] The anisotropic diffusion layer, the isotropic diffusion layer B, and the lens layer produced as described above were not closely adhered, and the light control film of Example 8 was formed by overlapping (the lens layer became the light exit surface side). Configuration under the state). φ [Example 9] The anisotropic diffusion layer, the isotropic diffusion layer C, and the lens layer produced as described above were not closely adhered, and the light control film of Example 9 was formed by overlapping (the lens layer became the light exit surface). Configured in the side state). [Comparative Example 1] The anisotropic diffusion layer, the isotropic diffusion layer C, and the isotropic diffusion layer C prepared as described above were not closely adhered to each other, and the light control film of Comparative Example 1 was formed by overlapping (isotropy) The diffusion layer C is disposed in a state of being on the light exit surface side. -59-201009397 [Comparative Example 2] The anisotropic diffusion layer, the isotropic diffusion layer D, and the isotropic diffusion layer D produced as described above were not closely adhered to each other, and the light control film of Comparative Example 2 was formed by overlapping. (Arranged in a state where the isotropic diffusion layer D is on the light exit surface side). [Comparative Example 3] The anisotropic diffusion layer and the isotropic diffusion layer A produced as described above were not closely adhered to each other, and the light control film of Comparative Example 3 was formed by overlapping (the isotropic diffusion layer A was a light exiting surface). Configured in the side state). [Comparative Example 4] The anisotropic diffusion layer and the lens layer produced as described above were not closely adhered to each other, and the light control film of Comparative Example 4 was formed so as to overlap (the lens layer was placed on the light-emitting surface side). [Comparative Example 5] The anisotropic diffusion layer, the isotropic diffusion layer D, and the lens layer produced as described above were not closely adhered to each other, and the light control film of Comparative Example 5 was formed so as to overlap (the lens layer became the light exit surface). Configured in the side state). [Comparative Example 6] The lens layer, the anisotropic diffusion layer, and the isotropic diffusion layer A produced as described above were not closely adhered to each other, and the light control film of Comparative Example 6 was formed by overlapping (-60-201009397 isotropic) The diffusion layer A is disposed in a state of being on the light exit surface side). [Comparative Example 7] The isotropic diffusion layer A, the lens layer, and the anisotropic diffusion layer prepared as described above were not closely adhered to each other, and the light control film of Comparative Example 7 was formed by overlapping (the anisotropic diffusion layer became light). It is arranged in the state of the exit surface side). [Comparative Example 8] The lens layer, the isotropic diffusion layer A, and the anisotropic diffusion layer produced as described above were not closely adhered to each other, and the light control film of Comparative Example 8 was formed by overlapping (the anisotropic diffusion layer became light). It is arranged in the state of the exit surface side). [Comparative Example 9] The anisotropic diffusion layer and the lens layer produced as described above were not closely adhered to each other, and the light control film of Comparative Example 9 was formed so as to overlap (the lens layer was placed in a state where the light was emitted from the surface side). <<3. Production of Backlight Device>> Next, light control of Examples 1 to 9 and Comparative Examples 1 to 9 was provided on a cold cathode tube of a 32-inch direct type backlight device (cold cathode tube (linear light source) 16 lamps). The film was used as the backlight devices of Examples 1 to 9 and Comparative Examples 1 to 9. In all of the examples and comparative examples, a light control film was provided in a state in which the long axis direction of the particle-shaped dispersed phase of the anisotropic diffusion layer was parallel to the axial direction of the linear light source. -61 - 201009397 "4. Evaluation" (1) The haze of the isotropic diffusion layer was measured by a haze meter (HGM-2K: SUGA Testing Machine Co., Ltd.) in accordance with JIS K71 36: 2000. Examples 1 to 9 were used. And the haze at the time of incidence of the diffusion surface of the isotropic diffusion layers A to D used in the light control films of Comparative Examples 1 to 9. The measurement results are shown in Tables 1 and 3. (2) The haze at the time of overlapping the isotropic diffusion layer was measured by using a haze meter (HGM-2K: SUGA Testing Machine Co., Ltd.), and the light of Examples 1 to 4 and Comparative Examples 1 to 2 was measured in accordance with JIS K7 1 36:2000. The two isotropic diffusion layers A to D used for the control film were superposed on each of the examples and the comparative examples to form a haze when light was incident on the diffusion surface of the isotropic diffusion layer. The measurement results are shown in Table 1. (3) Front luminance The front luminance of the center of the light exit surface of the direct type backlight device using the light control films of Examples 1 to 9 and Comparative Examples 1 to 9 was measured. The measurement results are shown in Table 2 and Table 3 (the unit is "Cd/m2"). (4) Elimination of lamp image When the backlight devices of Examples 1 to 9 and Comparative Examples 1 to 9 were lighted, the lamp image in the front direction of the backlight unit was visually confirmed. When the lamp image was visually observed, it was evaluated as "◎ ◎" when it was completely unrecognizable, and the lamp image - 62 - 201009397 was hardly found as " ◎", and several lamp images were confirmed, but the user evaluation was not affected. 〇J, the person who can confirm the lamp image is evaluated as "X". The evaluation results are shown in Table 2 and Table 3. [Table 1] Composition (light incident surface - light exit surface) Haze of the isotropic diffusion layer (%) Complex haze ※ (%) Example 1 Anisotropic diffusion layer, isotropic diffusion layer A, etc. Diffusion layer A 91 96 Example 2 Isotropic diffusion layer A, anisotropic diffusion layer, isotropic diffusion layer A 91 96 Example 3 Isotropic diffusion layer A, isotropic diffusion layer A, anisotropy Diffusion layer 91 96 Example 4 Anisotropic diffusion layer, isotropic diffusion layer B, isotropic diffusion layer B 84 93 Comparative Example 1 Anisotropic diffusion layer, isotropic diffusion layer C, isotropic diffusion layer C 67 84 Comparative Example 2 Anisotropic diffusion layer, isotropic diffusion layer D, isotropic diffusion layer D 46 73 Comparative Example 3 Anisotropic diffusion layer, isotropic diffusion layer A 91 _ Comparative Example 4 Anisotropic diffusion Layer, Mirror Sheet _ A "complex haze" in the table refers to the haze of overlapping two isotropic diffusion layers. [Table 2]
構成(光入射面^光射出面） 正面亮度 (cd/m2) 燈圖像之 消除性 實施例1 異向性擴散層，等方性擴散層Λ，等方性擴散層Λ 7764 ◎ 實施例2 等方性擴散層Α,異向性擴散層,等方性擴散層Λ 7116 ◎ 實施例3 等方性擴散層Α,等方性擴散層Α,異向性擴散層 6345 ◎ 實施例4 異向性擴散層,等方性擴散層B，等方性擴散層B 6657 〇 比較例1 異向性擴散層，等方性擴散層C,等方性擴散層C 6085 X 比較例2 異向性擴散層,等方性擴散層D,等方性擴散層D 5940 X 比較例3 異向性擴散層，等方性擴散層Λ 6915 X 比較例4 異向性擴散層，菱鏡薄片 8600 X 由表1及表2可了解以下的事項。實施例1〜4之光控 -63- 201009397 制薄膜係由二片等方性擴散層與異向性擴散層所構成所成 者，前述等方性擴散層之霧度均爲70%以上，因此組裝實 施例1~4之光控制薄膜之實施例1~4的背光裝置均爲正面 亮度及燈圖像之消除性良好者。重疊實施例1〜4之光控制 薄膜所含有之二片等方性擴散層時的霧度均爲9 0%以上。 特別是實施例1 ~3之光控制薄膜係因等方性擴散層之 霧度爲90%以上，因此組裝實施例1〜3之光控制薄膜之實 施例1〜3的背光裝置係正面亮度與燈圖像之消除性優異者 〇 實施例1之光控制薄膜係由光入射面朝光射出面，依 據異向性擴散層、二片等方性擴散層之順序配置所成者， 因此組裝實施例1之光控制薄膜之實施例1的背光裝置， 即使在實施例中，正面亮度與燈圖像之消除性特別優異者 〇 此外，如上述製作之異向性擴散層，除了牽伸比設定 爲6·3倍外，其餘與上述同樣，製作兩面形成透明樹脂層 的異向性擴散層（總厚度：205 μιη、各透明樹脂層之厚度： 41 μιη、異向性擴散層之厚度：123 μπι)。兩面形成該透明 樹脂層之異向性擴散層的全光線透過率爲83%，異方度爲 10。又，粒子狀分散相之縱橫比具有48.2(短軸之平均長 度0.48μιη及長軸之平均長度23.3μιη)。 使用兩面形成該透明樹脂層的異向性擴散層，與實施 例1〜5同樣製作光控制薄膜及背光裝置，關於正面亮度及 燈圖像之消除性進行評價，與上述實施例1〜5的結果同樣 -64- 201009397 ，可得到正面亮度及燈圖像之消除性良好的結果。 比較例1及2之光控制薄膜雖由異向性擴散層與二片 等方性擴散層所構成，但是前述等方性擴散層之霧度均未 達7 0%，因此組裝比較例1及2之光控制薄膜之比較例1 及2的背光裝置係正面亮度低，且燈圖像之消除性較差。 比較例3之光控制薄膜雖具備異向性擴散層與等方性 擴散層，但是該等方性擴散層僅具備一片，因此即使顯示 0 等方性擴散層之霧度高爲90%的數値，但是燈圖像之消除 性差。 比較例4之光控制薄膜雖具備異向性擴散層與透鏡層 ，但是未具備等方性擴散層，因此正面亮度雖高，但是光 之擴散性不足的結果，造成燈圖像之消除性差。 作爲参考例爲在實施例1之光控制薄膜中去除異向性 擴散層，在冷陰極管上配置厚度2mm之擴散板，該擴散 板上配置實施例1使用之由二片等方性擴散層A所構成之 • 光控制薄膜外，與實施例1同樣製作無異向性擴散層之光 控制薄膜及使用其之背光裝置。 確認使用該光控制薄膜之背光裝置之正面亮度及燈圖 像之消除性，結果因擴散板爲厚者（擴散層之厚度：2mm) ，因此燈圖像之消除性雖與實施例1同等，但是正面亮度 比實施例1降低約一成左右。又，相較於實施例1之異向 性擴散層（含有透明樹脂層之總厚度：175μιη)而言’因擴 散板之厚度爲2mm非常厚，因此無法達到背光裝置之薄 型化的要求。 -65- 201009397 表3]Configuration (light incident surface, light exit surface) Front luminance (cd/m2) Elimination of lamp image Example 1 Anisotropic diffusion layer, isotropic diffusion layer Λ, isotropic diffusion layer 764 7764 ◎ Example 2 Isotropic diffusion layer 异, anisotropic diffusion layer, isotropic diffusion layer Λ 7116 ◎ Example 3 isotropic diffusion layer Α, isotropic diffusion layer Α, anisotropic diffusion layer 6345 ◎ Example 4 Diffusion layer, isotropic diffusion layer B, isotropic diffusion layer B 6657 〇 Comparative Example 1 Anisotropic diffusion layer, isotropic diffusion layer C, isotropic diffusion layer C 6085 X Comparative Example 2 Anisotropic diffusion Layer, isotropic diffusion layer D, isotropic diffusion layer D 5940 X Comparative Example 3 Anisotropic diffusion layer, isotropic diffusion layer Λ 6915 X Comparative Example 4 Anisotropic diffusion layer, prism sheet 8600 X 1 and Table 2 can understand the following items. The light control of Examples 1 to 4 - 63 - 201009397 The film is composed of two isotropic diffusion layers and an anisotropic diffusion layer, and the haze of the isotropic diffusion layer is 70% or more. Therefore, the backlight devices of the first to fourth embodiments in which the light control films of Examples 1 to 4 are assembled are excellent in front luminance and lamp image erasing. When the two isotropic diffusion layers contained in the light control film of Examples 1 to 4 were superposed, the haze was 90% or more. In particular, in the light control films of Examples 1 to 3, since the haze of the isotropic diffusion layer was 90% or more, the backlights of Examples 1 to 3 in which the light control films of Examples 1 to 3 were assembled were front luminance and In the light control film of the first embodiment, the light control film of the first embodiment is disposed on the light exit surface, and is arranged in the order of the anisotropic diffusion layer and the two isotropic diffusion layers. In the backlight device of the first embodiment of the light control film of Example 1, even in the embodiment, the front luminance and the lamp image are particularly excellent in the erasability, and the anisotropic diffusion layer produced as described above is not limited in the draft ratio. In the same manner as above, an anisotropic diffusion layer having a transparent resin layer formed on both sides was produced (total thickness: 205 μm, thickness of each transparent resin layer: 41 μm, thickness of the anisotropic diffusion layer: 123). Ππι). The anisotropic diffusion layer forming the transparent resin layer on both sides had a total light transmittance of 83% and an anisotropy of 10. Further, the aspect ratio of the particulate dispersed phase was 48.2 (the average length of the short axis was 0.48 μm and the average length of the long axis was 23.3 μm). The light-control film and the backlight device were produced in the same manner as in Examples 1 to 5, using the anisotropic diffusion layer in which the transparent resin layer was formed on both sides, and the front luminance and the erasability of the lamp image were evaluated, and the above-described Examples 1 to 5 were used. The result is the same -64-201009397, and the result of good front luminance and lamp image elimination is obtained. The light control films of Comparative Examples 1 and 2 are composed of an anisotropic diffusion layer and two isotropic diffusion layers, but the haze of the isotropic diffusion layer is less than 70%, so that Comparative Example 1 and The backlight devices of Comparative Examples 1 and 2 of the light control film of 2 have low front luminance and poor cancelability of the lamp image. Although the light control film of Comparative Example 3 includes an anisotropic diffusion layer and an isotropic diffusion layer, the isotropic diffusion layer has only one sheet, and therefore the haze of the 0-isotropic diffusion layer is 90%. Oh, but the elimination of the lamp image is poor. The light control film of Comparative Example 4 includes the anisotropic diffusion layer and the lens layer. However, since the isotropic diffusion layer is not provided, the front luminance is high, but the light diffusibility is insufficient, resulting in poor cancellation of the lamp image. As a reference example, the anisotropic diffusion layer was removed in the light control film of Example 1, and a diffusion plate having a thickness of 2 mm was disposed on the cold cathode tube, and the two sheets of the isotropic diffusion layer used in Example 1 were disposed on the diffusion plate. A light control film having no anisotropic diffusion layer and a backlight device using the same were produced in the same manner as in Example 1 except for the light control film. The front side luminance of the backlight device using the light control film and the erasing property of the lamp image were confirmed. As a result, since the diffusion plate was thick (thickness of the diffusion layer: 2 mm), the lamp image was eliminated in the same manner as in the first embodiment. However, the front luminance is reduced by about one percent from that of the first embodiment. Further, compared with the anisotropic diffusion layer of Example 1 (the total thickness of the transparent resin layer: 175 μm), since the thickness of the diffusion plate is 2 mm, the thickness of the backlight device cannot be reduced. -65- 201009397 Table 3]
構成(光入射面—光射出面） 霧度 (%) 正面亮度 (cd/m2) 光圖像之 消除性 實施例5 異向性擴散層,等方性擴散層A，菱鏡薄片 91 9745 ◎ ◎ 實施例6 等方性擴散層A，異向性擴散層，菱鏡薄片 91 8908 ◎ ◎ 實施例7 異向性擴散層，菱鏡薄片，等方性擴散層A 91 9070 ◎ ◎ 實施例8 異向性擴散層，等方性擴散層B，菱鏡薄片 84 9521 ◎ ◎ 實施例9 異向性擴散層,等方性擴散層C，菱鏡薄片 67 9384 ◎ 比較例5 異向性擴散層,等方性擴散層D，菱鏡薄片 46 9308 X 比較例6 菱鏡薄片，異向性擴散層，等方性擴散層A 91 7625 X 比較例7 等方性擴散層A，菱鏡薄片，異向性擴散層 91 6858 X 比較例8 菱鏡薄片，等方性擴散層A，異向性擴散層 91 6768 X 比較例9 異向性擴散層，菱鏡薄片 • 8600 X 由表3可了解以下的事項。實施例5~9之光控制薄膜 係由異向性擴散層、等方性擴散層、透鏡層所構成，光控 制薄膜之等方性擴散層的霧度爲60%以上，且透鏡層被配 置於比異向性擴散層更接近光射出面側，因此組裝實施例 5~9之光控制薄膜之實施例5〜9的背光裝置均爲正面亮度 高，燈圖像之消除性良好者。 特別是實施例5之光控制薄膜係由光入射面朝光射出 面，依異向性擴散層、等方性擴散層、透鏡層之順序配置 所成者，因此組裝實施例5之光控制薄膜之實施例5的背 光裝置係正面亮度與燈圖像之消除性特別優異者。 實施例5~8之光控制薄膜係等方性擴散層之霧度爲 8 0%以上，因此組裝實施例5及6之光控制薄膜之實施例 5及6的背光裝置係正面亮度與燈圖像之消除性特別優異 -66- 201009397 者。 此外，如上述製作之異向性擴散層，除了牽伸比設定 爲6.3倍外，其餘與上述同樣，另外製作兩面形成透明樹 脂層的異向性擴散層（總厚度：205 μιη、各透明樹脂層之厚 度：41μηι、異向性擴散層之厚度：123μηι)。兩面形成該 透明樹脂層之異向性擴散層的全光線透過率爲83%，異方 度爲10。又，粒子狀分散相之縱橫比具有48.2(短軸之平 φ 均長度0.48μιη及長軸之平均長度23.3μπι)。 使用兩面形成該透明樹脂層的異向性擴散層，與實施 例5〜9同樣製作光控制薄膜及背光裝置，關於正面亮度及 燈圖像之消除性進行評價，與上述實施例5〜9的結果同樣 ，可得到正面亮度及燈圖像之消除性良好的結果。 比較例5之光控制薄膜雖由異向性擴散層、等方性擴 散層、透鏡層所構成，光控制薄膜之透鏡層雖配置於比異 向性擴散層更接近光射出面側，但是等方性擴散層之霧度 • 未達60，因此組裝比較例5之光控制薄膜之比較例5的背 光裝置係燈圖像之消除性較差者。 比較例6〜8之光控制薄膜雖由異向性擴散層、等方性 擴散層、透鏡層所構成，但是光控制薄膜之透鏡層配置於 比異向性擴散層更接近光入射面側，因此組裝比較例6〜8 之光控制薄膜之比較例6~8的背光裝置即使顯示等方性擴 散層之霧度爲80%以上，但是正面亮度低，且燈圖像之消 除性差。 比較例9之光控制薄膜雖具備異向性擴散層與透鏡層 -67- 201009397 ，但是未具備等方性擴散 之擴散性不足的結果，造 作爲参考例爲在實施 擴散層，在冷陰極管上配 板上配置實施例5使用之 之光控制薄膜外，與實施 光控制薄膜及使用其之背 確認使用該光控制薄 像之消除性，結果因擴 ，因此燈圖像之消除性雖 比實施例5降低約一成左 性擴散層（含有透明樹脂 散板之厚度爲2mm非常 型化的要求。 [產業上之利用性] 如以上說明，本發明 度化，也可抑制燈圖像之 溫下使用，長期間仍可抑 單元可對顯示單元均一兩 晶顯示裝置等）或背光型 源被配設於顯示單元之正 種畫面尺寸、特別是具有 因此適合作爲此種大畫面 層，因此正面亮度雖高，但是光 成燈圖像之消除性差。 例5之光控制薄膜中去除異向性 置厚度2mm之擴散板，該擴散 透鏡層、等方性擴散層A所構成 例5同樣製作無異向性擴散層之 光裝置。 膜之背光裝置之正面亮度及燈圖 :板爲厚者（擴散層之厚度：2mm) 與實施例5同等，但是正面亮度 右。又，相較於實施例5之異向 層之總厚度：175μιη)而言，因擴 厚，因此無法達到背光裝置之薄 之光制御薄片即使薄型化且高亮 產生，同時耐熱性高，即使在高 制光散射特性之變化，藉由背光 吴明。因此，可作爲顯示裝置（液 光源裝置之構件使用。特別是光 下之直下型背光單元可適用於各 大畫面之顯示單元之顯示裝置’ 之顯示單元或背光單元之構成構 -68- 201009397 件。顯示單元之畫面尺寸無特別限定，例如可爲20吋以 上（例如23-300吋，較佳爲30〜2 20吋）。 【圖式簡單說明】 [圖1 ]圖1係表示本發明之一實施形態之光控制薄膜 之異向性擴散層之一例的剖面圖。 [圖2]圖2係表示本發明之一實施形態之光控制薄膜 m 之異向性擴散層之其他例的剖面圖。 [圖3]圖3係說明本發明之一實施形態之光控制薄膜 之異向性擴散層之異向性散射之槪念圖。 [圖4]圖4係說明可測定圖3之異向性擴散層之光散 射特性之裝置之一例的槪略斜視圖。 [圖5]圖5係表示第1觀點之光控制薄膜之一例的斜 視圖。 [圖6]圖6係表示第1觀點之光控制薄膜之其他例的 • 斜視圖。 [圖7]圖7係表示第2觀點之光控制薄膜之一例的斜 視圖。 [圖8]圖8係表示第2觀點之光控制薄膜之其他例的 斜視圖。 [圖9]圖9係表示第1觀點之背光裝置及透過型液晶 顯示裝置之一例的剖面圖。 [圖10]圖10係表示第2觀點之背光裝置及透過型液 晶顯示裝置之一例的剖面圖。 -69- 201009397 【主要元件符號說明】 1 :線狀光源（冷陰極管） 2 :反射板 3 :擴散板 4 :稜鏡薄片 5 :面型顯示單元 6a，6b :偏光薄膜 7a，7b :玻璃基板 8 a，8 b :電極 9a，9b :配向膜 1 〇 :液晶層 1 1 :彩色濾光片 1 2 :等方性擴散層 1 3 :背光單元 14，17，28，37，47 :異向性擴散層 17a，27a，37a，47a ：連續相 17b，27b，37b > 47b:分散相 29，49 :透明樹脂層 46 :透鏡層 4 6 a :透鏡單位 -70-Configuration (light incident surface - light exit surface) Haze (%) Front luminance (cd/m2) Elimination of optical image Example 5 Anisotropic diffusion layer, isotropic diffusion layer A, prism sheet 91 9745 ◎ ◎ Example 6 Isotropic diffusion layer A, anisotropic diffusion layer, prism sheet 91 8908 ◎ ◎ Example 7 Anisotropic diffusion layer, prism sheet, isotropic diffusion layer A 91 9070 ◎ ◎ Example 8 Anisotropic diffusion layer, isotropic diffusion layer B, prism sheet 84 9521 ◎ ◎ Example 9 Anisotropic diffusion layer, isotropic diffusion layer C, prism sheet 67 9384 ◎ Comparative Example 5 Anisotropic diffusion layer , isotropic diffusion layer D, prism sheet 46 9308 X Comparative Example 6 Mirror sheet, anisotropic diffusion layer, isotropic diffusion layer A 91 7625 X Comparative Example 7 Isotropic diffusion layer A, prism sheet, Anisotropic diffusion layer 91 6858 X Comparative Example 8 Rhombus sheet, isotropic diffusion layer A, anisotropic diffusion layer 91 6768 X Comparative Example 9 Anisotropic diffusion layer, prism sheet • 8600 X It can be understood from Table 3. The following matters. The light control films of Examples 5 to 9 are composed of an anisotropic diffusion layer, an isotropic diffusion layer, and a lens layer, and the isotropic diffusion layer of the light control film has a haze of 60% or more, and the lens layer is disposed. Since the specific anisotropic diffusion layer is closer to the light exit surface side, the backlight devices of Examples 5 to 9 in which the light control films of Examples 5 to 9 are assembled have high front luminance and good lamp image erasability. In particular, the light control film of the fifth embodiment is formed by arranging the light incident surface toward the light exit surface in the order of the anisotropic diffusion layer, the isotropic diffusion layer, and the lens layer. Therefore, the light control film of Example 5 is assembled. The backlight device of the fifth embodiment is particularly excellent in the front luminance and the cancellation of the lamp image. The haze of the light-control film-like isotropic diffusion layer of Examples 5 to 8 was 80% or more. Therefore, the backlights of Examples 5 and 6 in which the light control films of Examples 5 and 6 were assembled were front luminance and lamp patterns. The elimination is particularly excellent - 66- 201009397. Further, the anisotropic diffusion layer prepared as described above was prepared in the same manner as described above except that the draft ratio was set to 6.3 times, and an anisotropic diffusion layer (total thickness: 205 μm, each transparent resin) having a transparent resin layer formed on both sides was separately prepared. Thickness of layer: 41 μm, thickness of anisotropic diffusion layer: 123 μηι). The anisotropic diffusion layer on which the transparent resin layer was formed on both sides had a total light transmittance of 83% and an anisotropy of 10. Further, the aspect ratio of the particulate dispersed phase was 48.2 (the flat axis of the short axis was 0.48 μm in length and the average length in the long axis was 23.3 μm). A light control film and a backlight device were produced in the same manner as in Examples 5 to 9 by using an anisotropic diffusion layer having the transparent resin layer formed on both sides, and the front luminance and the erasability of the lamp image were evaluated, and the above-described Examples 5 to 9 were used. As a result, the result of good front luminance and lamp image erasability was obtained. The light control film of Comparative Example 5 is composed of an anisotropic diffusion layer, an isotropic diffusion layer, and a lens layer, and the lens layer of the light control film is disposed closer to the light exit surface than the anisotropic diffusion layer, but Since the haze of the square diffusion layer was less than 60, the backlight of the comparative example 5 of the light control film of Comparative Example 5 was poorly eliminated. The light control film of Comparative Examples 6 to 8 is composed of an anisotropic diffusion layer, an isotropic diffusion layer, and a lens layer, but the lens layer of the light control film is disposed closer to the light incident surface side than the anisotropic diffusion layer. Therefore, in the backlight devices of Comparative Examples 6 to 8 in which the light control films of Comparative Examples 6 to 8 were assembled, even if the haze of the isotropic diffusion layer was 80% or more, the front luminance was low, and the erasability of the lamp image was poor. The light control film of Comparative Example 9 has an anisotropic diffusion layer and a lens layer-67-201009397, but does not have the effect of insufficient diffusion of the isotropic diffusion. As a reference example, the diffusion layer is implemented in the cold cathode tube. The light control film used in Example 5 was placed on the upper plate, and the light control film was used and the back of the light control film was used to confirm the elimination of the light control thin image. As a result, the elimination of the lamp image was In the embodiment 5, it is required to reduce the thickness of the transparent diffusion resin sheet to a thickness of 2 mm. [Industrial Applicability] As described above, the present invention can also suppress the image of the lamp. The use of a warm-down period, a long-term suppression unit, a display unit, a two-crystal display device, or the like, or a backlight-type source, which is disposed on the display unit, is particularly suitable as such a large-screen layer. Although the front brightness is high, the image of the light-emitting lamp is poorly eliminated. In the light-control film of Example 5, the anisotropic property was set to a diffusion plate having a thickness of 2 mm, and the diffusion lens layer and the isotropic diffusion layer A were formed in the same manner as in Example 5 except that an optical device having no anisotropic diffusion layer was produced. Front side brightness and lamp pattern of the film backlight device: The thickness of the plate (thickness of the diffusion layer: 2 mm) is the same as that of the embodiment 5, but the front brightness is right. Further, compared with the total thickness of the anisotropic layer of Example 5: 175 μm), since the thin film of the backlight device cannot be made thinner and brighter, the heat resistance is high, even at high light control. Changes in scattering characteristics, by backlighting Wu Ming. Therefore, it can be used as a display device (a component of a liquid light source device, in particular, a display unit or a backlight unit of a direct-type backlight unit that can be applied to a display unit of each large screen)-68-201009397 The screen size of the display unit is not particularly limited, and may be, for example, 20 吋 or more (for example, 23-300 吋, preferably 30 〜 2 20 吋). [FIG. 1] FIG. 1 shows the present invention. Fig. 2 is a cross-sectional view showing another example of the anisotropic diffusion layer of the light control film m according to the embodiment of the present invention. Fig. 2 is a cross-sectional view showing another example of the anisotropic diffusion layer of the light control film m according to the embodiment of the present invention. Fig. 3 is a view showing an anisotropic scattering of an anisotropic diffusion layer of a light control film according to an embodiment of the present invention. [Fig. 4] Fig. 4 is a view showing that the anisotropy of Fig. 3 can be determined. Fig. 5 is a perspective view showing an example of the light control film of the first aspect. Fig. 6 is a perspective view showing the first viewpoint. • An oblique view of other examples of light control films. [Fig. 7] Fig. 7 Fig. 8 is a perspective view showing another example of the light control film of the second aspect. Fig. 9 is a view showing a backlight of the first aspect. And FIG. 10 is a cross-sectional view showing an example of a backlight device and a transmissive liquid crystal display device according to a second aspect. -69- 201009397 [Description of main component symbols] 1 : Linear light source (cold cathode tube) 2: Reflector 3: Diffuser 4: 稜鏡 Sheet 5: Surface type display unit 6a, 6b: Polarizing film 7a, 7b: Glass substrate 8 a, 8 b : Electrodes 9a, 9b: Alignment film 1 〇: liquid crystal layer 1 1 : color filter 1 2 : isotropic diffusion layer 13 : backlight unit 14, 17, 28, 37, 47: anisotropic diffusion layers 17a, 27a, 37a, 47a: Continuous phase 17b, 27b, 37b > 47b: dispersed phase 29, 49: transparent resin layer 46: lens layer 4 6 a : lens unit - 70-