201011352 六、發明說明： 【發明所屬之技術領域】 本發明有關很適合將含有抗靜電劑之溶液均勻塗佈之 用的光擴散基板、及由於均勻的防帶塗佈層之形成而很適 合作爲能充分防止灰塵等的附著之直下型背光板（direct backlight)用之光擴散板（optical diffusion plate)。 在此，於本說明書及申請專利範圍中，「水接觸角（water φ contact angle)」一語，乃係指準據JIS K6768-1 999所測定 之對樹脂板的表面之純水的接觸角（contact angle)之意。 【先前技術】 液晶顯示裝置而言，周知有於液晶面板（liquid crystal panel)(影像顯示部）的背面側配置有直下型背光板之構成 者。前述直下型背光板而言，周知有一種經於光反射板 (optical reflector)配置複數個光源之同時，尙於此等光源 的前面側配置有光擴散板之構成者（參考專利文獻1:日本 專利「特開2004- 1 7093 7號公報」）。 近年來，急速進展有液晶顯示裝置、尤其液晶電視的 大型化，惟如欲將畫面大型化以確保足夠的亮度起見而增 多光源數時，則光源的發熱量將大大地增大。於是，當進 行畫面的大型化時，需要有效排出內部所發生之熱。 於直下型背光板裝置上，爲排熱起見，多設置有送風 器（fan)。係藉由排熱送風器之送風而進行直下型背光板裝 置內部的換氣，以實施冷卻者。然而，如按此方式送風時 -5- 201011352 ，則有光擴散板表面容易附著灰塵之問題。如在光擴散板 表面附著有灰塵等時，則有影像混亂，或影像的明晰度或 亮度會降低之可能性。 爲防止此種灰塵附著起見，光擴散板需要具備有優異 的防帶電性能。 於是，爲使光擴散板具備防帶電性能起見，有一種於 合成樹脂製的光擴散板表面塗佈抗靜電劑水溶液，藉以使 表面形成防帶電塗佈層之作法之提案（參考專利文獻2:日 本專利「特開2006-33 0546號公報」、專利文獻3:日本 專利「特開2007- 1 78544號公報」）、專利文獻4 :日本專 利「特開2008- 1 941 1號公報」）。 【發明內容】 然而，經本發明人硏究之結果發現，當於合成樹脂製 的光擴散板表面塗佈抗靜電劑水_液時，有容易發生抗靜 電劑水溶液不會均句擴散在表面之情形，容易發生抗靜電 劑旳塗佈的濃淡不均勻，因而有防止灰塵附著情況部分性 不足之可能性。特別是，如於丙烯聚合物製的光擴散板上 塗佈抗靜電劑水溶劑時，則顯著容易發生抗靜電劑的塗佈 的濃淡不均勻之情況。 本發明，係鑑於此種技術性背景所開發者，以提供一 種當塗佈含有抗靜電劑之溶液時能均勻塗佈該溶液而難於 發生塗佈的濃淡不均勻之光擴散基板、以及能按涵蓋全面 之方式防止灰塵的附著之防帶電性的光擴散板爲目的。再 -6- 201011352 者，以提供一種在光擴散板表面難於附著灰塵之下能顯示 良好的影像之液晶顯示裝置爲目的。 爲達成前述目的起見，本發明提供下列手段。 [1] · 一種光擴散基板’其特徵爲：於含有透明樹脂之光擴 散性樹脂板的至少一面，施加有電暈放電處理。 [2] .如前述[1]所記載之光擴散基板，其中前述透明樹脂， 係丙烯聚合物或苯乙烯聚合物。 _ [3].—種光擴散基板，其特徵爲：含有丙烯聚合物之樹脂 形成至少一側的表面，而其表面的水接觸角爲90°以下。 [4] . 一種光擴散基板，其特徵爲：含有苯乙烯聚合物之樹 脂形成至少一側的表面，而其表面的水接觸角爲60°以下 〇 [5] ·—種光擴散板，其特徵爲：於前述[1]或[2]所記載之光 擴散基板的電暈放電處理面，層合有含有抗靜電劑之塗佈 層。 φ [6].—種光擴散板，其特徵爲：於前述[3]所記載之光擴散 基板的水接觸角爲90°以下之表面，層合有含有抗靜電劑 之塗佈層。 [7] ·—種光擴散板，其特徵爲：於前述[4]所記載之光擴散 基板的水接觸角爲60°以下之表面，層合有含有抗靜電劑 之塗佈層。 [8] ·如前述[5]至[7]之任一項所記載之光擴散板，其中前述 塗佈層，係使含有抗靜電劑之溶液塗佈於光擴散基板並乾 燥所形成者。 -7- 201011352 [9] . 一種光擴散板之使用，係作爲直下型背光板內的部件 的前述[5]至[8]之任一項所記載之光擴散之使用。 [10] ·—種直下型背光板，其特徵爲：具備有前述[5]至[8] 之任一項之光擴散板、及經配置於該光擴散板的背面側之 複數個光源。 [11】.一種液晶顯示裝置，其特徵爲：具備有[5]至[8]之任 一項所記載之光擴散板、及經配置於該光擴散板的背面側 之複數個光源、以及經配置於該光擴散板的前面側之液晶 面板。 於[1]的發明中，由於含有透明樹脂之光擴散性樹脂板 的至少一個施加有電暈放電處理之故，如於該電暈放電處 理面塗佈含有抗靜電劑之溶液，則可均勻加以塗佈（亦即 ，經抑制抗靜電劑的塗佈的濃淡不均勻），因而可形成均 勻的防帶電塗佈層之結果，可提供一種可按涵蓋全面之方 式充分防止灰塵等的附著之光擴散板。 於[2]的發明中，透明樹脂，係屬於丙烯聚合物或苯乙 烯聚合物之構成者，由於可作爲光擴散板而使用很合適的 材料，以均勻方式塗佈含有抗靜電劑之溶液（亦即，經抑 制抗靜電劑的塗佈的濃淡不均勻），因而可形成均句的防 帶電塗佈層之結果，可提供一種可按涵蓋全面之方式充分 防止灰塵等的附著之光擴散板。 於[3]的發明中，由於含有丙烯聚合物之樹脂形成至少 一側的表面，並其表面的水接觸角爲90°以下之故’如對 該表面塗佈含有抗靜電劑之溶液’則可均勻加以塗佈（亦 -8- 201011352 即，經抑制抗靜電劑的塗佈的濃淡不均勻），因而可形成 均勻的防帶電塗佈層之結果，可提供一種可按涵蓋全面之 方式充分防止灰塵等的附著之光擴散板。 於[4]的發明中，由於含有苯乙烯聚合物之樹脂形成至 少一側的表面，並其表面的水接觸角爲60°以下之故，如 對該表面塗佈含有抗靜電劑之溶液，則可均勻加以塗佈（ 亦即，經抑制抗靜電劑的塗佈的濃淡不均勻），因而可形 成均勻的防帶電塗佈層之結果，可提供一種可按涵蓋全面 之方式充分防止灰塵等的附著之光擴散板。 於[5][的發明中，由於於上述[1]或[2]的光擴散基板的 電暈放電處理面上，層合有含有抗靜電劑之塗佈層之故， 形成有均勻的防帶電塗佈層，因而可按涵蓋全面之方式充 分防止對此光擴散板的灰塵等的附著。 於[6]的發明中，由於上述[3]的光擴散基板的水接觸 角爲90°以下之表面，層合有含有抗靜電劑之塗佈層之故 ，形成有均勻的防帶電塗佈層，因而可按涵蓋全面之方式 充分防止對此光擴散板的灰塵等的附著。 於[7]的發明中，由於上述[4]的光擴散基板的水接觸 角爲60°以下之表面，層合有含有抗靜電劑之塗佈層之故 ，形成有均勻的防帶電塗佈層，因而可按涵蓋全面之方式 充分防止對此光擴散板的灰塵等的附著。 於[8]的發明中，由於塗佈層，係使含有抗靜電劑之溶 液塗佈於上述[5]至[7]的任一光擴散基板並乾燥所形成者 之故，可提供一種可按涵蓋全面之方式充分防止灰塵等的 201011352 附著之光擴散板。 於[9]的發明中，可提供作爲可按涵蓋全面之方式充分 防止灰塵等的附著之防帶電性能優異的光擴散板的直下型 背光板內的部件的用途。 於[10]的發明中，由於構成直下型背光板之光擴散板 、係按涵蓋全面之方式具備有均勻的防帶電性能之故，可 按涵蓋長期之方式確保高亮度的背光板光。 於[11]的發明中，由於構成液晶顯示裝置之光擴散板 、係按涵蓋全面之方式具備有均与的防帶電性能之故，可 按涵蓋長期之方式顯示高品質且高品位的影像（亦即，影 像不易發生混亂、且鋒利而高亮度的影像）。 [發明之最佳實施形態] 將有關本發明之光擴散基板（2)的一實施形態，表示於 第1圖。該光擴散基板（2)，係於含有透明樹脂之光擴散性 樹脂板（6)的一面，施加有電暈放電處理者。亦即，一面爲 電暈放電處理面（6a)。本實施形態中，作爲前述光擴散性 樹脂板（6)，而採用於基底層（base layer)(21)的兩面層合表 面層（facing layer)(22)(22)之層合板。當然，前述光擴散 性樹脂板（6)’可爲由單層所成之構造（參考第4圖）。又， #實施形態中’係採用僅於光擴散性樹脂板（6)的單面施加 有®暈放電處理之構成者，惟亦可採用於光擴散性樹脂板 (6) Mffi施力卩有電暈放電處理而形成爲電暈放電處理面 (6a)(6a)之構成（參考第4圖）。 201011352 於上述構成之光擴散基板（2)中，由於至少一面係經形 成爲電暈放電處理面（6 a)之故，如於該電暈放電處理面 (6 a)上塗佈含有抗靜電劑之溶液時，則可抑制抗靜電劑的 塗佈的濃淡不均而均勻進行塗佈，亦即可形成均勻的防帶 電塗佈層（3)之故，能提供一種按涵蓋全面之方式充分防止 灰塵等的附著之光擴散板（1)(參考第2圖）。 前述電暈放電處理的條理條件而言，並不特別加以限 φ 定，惟較佳爲作爲被處理對象物之光擴散性樹脂板（6)通過 電暈放電領域時的移動速度（linear velocity，線速度）設定 於1至20m/分鐘。又，較佳爲將電暈放電處理的施加電 力設定爲100至1 000W(瓦特），其中，特佳爲設定於150 至 900W。 如實施此種電暈放電處理，則例如，於含有丙烯聚合 物之光擴散性樹脂板（6)中，能將其表面（電暈放電處理面） 的水接觸角作成90°以下，又，於含有苯乙烯聚合物之光 φ 擴散性樹脂板（6)中，能將其表面（電暈放電處理面）的水接 觸角作成60°以下。由於利用此種電暈放電處理，即可將 表面（電暈放電處理面）的水接觸角變小之故，可推想如於 該電暈放電處理面（6 a)塗佈含有抗靜電劑之溶液，則能抑 制抗靜電劑的塗佈的濃淡不均勻而成爲均勻進行塗佈者。 可推想由於前述電暈放電處理，而因 a) 表面變成粗糙、 b) 在表面生成自由基等的親水性的官能基、 的作用，而對水接觸角變小上有所貢獻者，惟詳細的作用 -11 - 201011352 機構則並不確定。 構成前述光擴散性樹脂板（6)之透明樹脂而言’並不特 別加以限定’惟可例舉··丙嫌聚合物、苯乙嫌聚合物、丙 烯腈-丁二烯-苯乙烯共聚物、低密度聚乙烯、高密度聚乙 烯、直鏈狀低密度聚乙烯、丙烯腈-苯乙烯共聚物、丙烯 酸-丙烯腈-苯乙烯共聚物、甲基丙烯酸甲酯聚合物、甲基 丙烯酸甲基-苯乙烯共聚物、聚縮醛、聚醯胺、聚對苯二 甲酸乙二醇酯、聚碳酸酯、聚颯、聚醚碾、甲基戊烯聚合 物、聚芳酯、聚對苯二甲酸丁二醇酯、含有含脂環構造之 乙烯基不飽和單體單元之樹脂、聚伸苯基硫醚、聚伸苯基 醚、聚醚型聚酮醚等、此等的通用塑料或工程塑料等。 前述丙烯聚合物而言，可爲使丙烯單獨進行聚合所製 得之同元聚丙烯、亦可爲丙烯及能與此進行共聚合之共聚 合成分的共聚物。其中，前述丙烯聚合物而言，較佳爲含 有丙烯單元50質量％以上所成之聚合物。再者，從能獲得 充分的剛性的觀點來看，特佳爲前述丙烯聚合物中的丙烯 單元的含量在98質量％以上。前述共聚合成分而言，並不 特別加以限定，惟可例舉：乙烯、1 -戊烯等的α -烯烴等。 前述苯乙烯聚合物而言，作爲其構成單元而具有苯乙 烯單元50質量％以上、較佳爲具有70質量％以上者，亦 可爲祇要是具有苯乙烯單元50質量％以上而其一部分爲能 與苯乙烯共聚合之不飽和單體單元所取代之共聚物。 能與苯乙烯基聚合之前述單官能不飽和單體而言，可 例舉：甲基丙烯酸甲酯、甲基丙烯酸丁酯、甲基丙烯酸環 -12- 201011352 己酯、甲基丙烯酸苯酯、甲基丙烯酸苄酯、甲基丙烯酸2-乙基己酯、甲基丙烯酸2-羥乙酯等的甲基丙烯酸酯類；丙 烯酸甲酯、丙烯酸乙酯、丙烯酸丁酯、丙烯酸環己酯、丙 烯酸苯酯、丙烯酸苄酯、丙烯酸2-乙基己酯、丙烯酸2-羥 乙酯等的丙烯酸酯類；甲基丙烯酸、丙烯酸等的不飽和酸 類；甲基苯乙烯、丙烯腈、甲基丙烯腈、馬來酸酐、 苯基馬來醯亞胺、環己基馬來醯亞胺等。又，該共聚物， ^ 可再含有戊二酸（glutaric acid)酐單元、戊二醯亞胺單元。 再者，亦可於前述的聚合物、共聚物中，作爲橡膠狀聚合 物而採用經將二烯系橡膠 '丙烯系橡膠等摻和（blend)者。 前述光擴散性樹脂板（6)，係一種具有光擴散功能之樹 脂板，例如，使其含有光擴散劑，則可賦與光擴散功能者 ，惟並不特別限定於由此種手法而賦與光擴散功能者。 前述光擴散劑而言，祇要是對前述透明樹脂爲非相溶 性而能顯示與該透明樹脂相異的折射率，並具有使穿透光 φ 擴散板後之穿透光加以擴散之功能之粒子（包含粉末），則 並不特別加以限定。例如，可爲玻璃粒子、玻璃纖維、二 氧化矽粒子、氫氧化鋁粒子、碳酸鈣粒子、硫酸鋇粒子、 氧化鈦粒子、滑石等的無機粒子，亦可爲苯乙烯系聚合物 粒子、丙烯酸系聚合物粒子、矽氧烷系聚合物粒子等的有 機粒子。 前述光擴散劑而言，通常採用其體積平均粒徑在0.5 至40μιη的範圍者。在此，體積平均粒徑（d5〇)，係指測定 全粒子的粒徑及體積，並從小的粒徑者依序累計體積後， -13- 201011352 該累計體積能對全粒子的合計體積成爲50%之粒子的粒徑 之意。 使光擴散劑分散於前述透明樹脂中之比例，係對前述 透明樹脂100質量份，較佳爲作成光擴散劑0.1至20質 量份的範圍。如作成0.1質量份以下則可確保充分的光擴 散性能之同時，作成20質量份以下則可防止板本身的耐 衝擊性的低落。 其次，將有關本發明之光擴散板（1)的一實施形態，表 示於第2圖。該光擴散板（1)，係於前述光擴散基板（2)的 電暈放電處理面（6a)上，層合有含有抗靜電劑之塗佈層（3) 者。本實施形態中，前述塗佈層（3)，係將含有抗靜電劑之 溶液塗佈於前述光擴散基板（2)的電暈放電處理面（6a)後使 其乾燥所形成者。 如採用上述構成之光擴散板（1)，則由於前述光擴散基 板（2)的電暈放電處理面（6a)上，層合有含有抗靜電劑之塗 佈層（3)之故，可形成均勻的防帶電塗佈層，因而可按涵蓋 全面之方式充分防止對該光擴散板（1)的灰塵等的附著。 前述抗靜電劑而言，並不特別加以限定，惟可例舉： 陽離子系抗靜電劑、陰離子系抗靜電劑、非離子系抗靜電 劑等。前述陽離子系抗靜電劑而言，並不特別加以限定， 惟可例舉：氯化月桂基三甲基銨、氯化硬脂基三甲基銨、 月桂基二乙醇胺、硬酯基胺鹽酸鹽等。前述陰離子系抗靜 電劑而言，並不特別加以限定，惟可例舉：烷基磷酸二乙 醇胺、烷基磷酸鉀、烷基苯磺酸鹽類等。前述非離子系抗 -14- 201011352 靜電劑而言，並不特別加以限定，惟可例舉：聚羥乙烯基 三癸基醚、聚羥乙烯基月桂基醚、聚乙二醇一油酸酯、聚 羥乙烯山梨糖醇酐一油酸酯等。 爲形成前述塗佈層（3)之用的含抗靜電劑之溶液而言’ 並不特別加以限定’惟可例舉：含抗靜電劑之水溶液、含 抗靜電劑之有機溶液。爲前有機溶液所用之有機溶劑而言 ，可例舉：乙醇等的醇類等。其中，從作爲衛生方面或環 Λ 境保全的觀點來看，較佳爲經塗佈含抗靜電劑之溶液以形 成前述塗佈層（3)之作法。 前述塗佈層（3)的形成方法而言，雖並不加以限定，惟 較佳爲藉由前述含抗靜電劑之溶液之塗佈而加以形成。前 述塗佈方法而言，並不特別加以限定，惟可例舉：輥式塗 佈機（roll coater)法、模唇塗佈（lip coating)法、刮刀塗佈 機（knife coater)法等。 於前述含抗靜電劑之溶液中之抗靜電劑的濃度，較佳 φ 爲設定爲〇.〇1至10質量％。又，於前述塗佈層（3)中之抗 靜電劑的附著量（在一面上之固體成分附著量），較佳爲設 定於〇.〇1至5g/cm2、特佳爲範圍爲0.05至2g/cm2。 再者，於上述實施形態（第2圖）中，光擴散板（1)，係 僅於前述光擴散基板（2)的一面上設置有塗佈層（3)之構成 ，惟亦可採用例如第4圖所示，於光擴散基板（2)的兩面的 電暈放電處理面（6 a) (6 a)上設置有塗佈層（3 )(3)之構成。 將採用上述光擴散板（1)所構成之液晶顯示裝置（30)的 一實施形態，表示於第3圖。於第3圖中，（35)爲液晶片 -15- 201011352 、（36)(37)爲偏光板、（31)爲直下型背光板。於前述液晶 片（35)的上下兩側分別配置有偏光板（3 6)(37)，而藉由此 等構成構件（3 5 )(36)(3 7)而構成有液晶面板（穿透型影像顯 示部）（38)。 前述背光板（31)，係經配置於前述下側的偏光板（37) 的下面側（背面側）。該背光板（31)，具備有：形成平面視 察矩形狀而經開放上面側（前面側）之略箱型形狀的燈管箱 盒（lamp box)(34)、及於該燈管箱盒內互相隔些距離所配 置之複數個光源（32)、及經配置於此等複數個光源（3 2)的 上方側（前面側）之光擴散板（1)、以及於該光擴散板（1)的 上方側介由空氣層（50)所配置之光學薄膜（33)(參考第3圖 )。前述光擴散板（1)，係於前述燈管箱盒（3 4)的上方近旁 位置中與該燈管箱盒（3 4)之間按形成有通氣間隙（40)之狀 態所配置者。又，於前述燈管箱盒（3 4)的內面，則設置有 光反射層。又，附設有爲排放前述燈管箱盒（34)內的空氣 之用的排風機（exhauster)(未圖示）。 於上述構成有關之液晶顯示裝置（30)中，由於使用排 風機並介由前述通氣間隙（40)而將前述燈管箱盒（34)內部 的高溫空氣往外排出之故，可有效排出背光板（31)內的發 熱。此時，雖因該燈管箱盒（3 4)內部的換氣而灰塵等亦會 侵入燈管箱盒（34)內，惟近接該燈管箱盒（34)所配置之前 述光擴散板（1)，係由於其表面（燈管箱盒側的表面）形成有 含有抗靜電劑之塗佈層（3)之故，可按涵蓋光擴散（1)表面（ 燈管箱盒側表面）的全面之方式防止灰塵之附著，藉此液晶 -16- 201011352 顯示裝置（30)，則可長時間顯示高品質且高品位的影像。 再者，前述光源（3 2)而言，並不特別加以限定，惟可 例舉：螢光管、鹵素燈、鎢絲燈、發光二極體等。 本發明有關之光擴散基板（2)、光擴散板（1)、直下型 背光板（3 1)以及液晶顯示裝置（3 0)，並不因上述實施形態 而特別有所限定，祇要是在申請專利範圍而並不脫離其精 神，則可容許任何設計上之變更者。 【實施方式】 [實施例] 其次，就本發明之具體實施例加以說明，惟本發明係 並不因此等實施例而特別有所限定者。 <實施例1> (表面層形成用材料之製造） Φ 經將苯乙烯·甲基丙烯酸甲酯共聚物（新日鐵化學公司 製「埃斯替連MS200NT」、苯乙烯單元80質量％、甲基 丙烯酸甲酯單元20質量％、MFR(熔流速率）1.3至1.9g/10 分鐘）7 5.8質量份、交聯丙烯酸系聚合物粒子（光擴散劑、 住友化學公司製「速美培克斯XC1A」、體積平均粒徑 30μιη)23·0質量份，紫外線吸收劑（ADEKA公司製「LA31 」）1.0質量份以及加工安定劑（住友化學公司製「速美賴 莎GP」0.2質量份進行乾式摻和後，置入於螺旋徑65mm 的雙軸擠出機，在200至260°C進行加熱熔融之下混練並 -17- 201011352 按股線（strand)狀擠出’並將此裁斷爲顆粒（pellet)狀後， 製得顆粒狀的表面層形成用材料。 (基底層用之光擴散劑母料（master batch)之製造） 經將苯乙烯聚合物（東洋苯乙烯公司製「東洋苯乙烯 HRM40」、折射率1.59、MFR0.9至1.3g/10分鐘）52質量 份、交聯丙烯酸系聚合物粒子（光擴散劑、住友化學公司 製「速美培克斯XC1A」）40質量份、聚矽氧橡膠粒子（光 擴散劑、東麗•陶康寧公司製「托列費爾DY3 3-719」、 體積平均粒徑2μιη)4質量份、紫外線吸收劑（住友化學公 司製「速美塑甫200」）2質量份以及加工安定劑（住友化學 公司製「速美賴莎GP)2質量份進行乾式摻和後，置入於 螺旋徑65 mm的雙軸擠出機，在80至250 °C進行加熱熔融 之下混練並按股線狀擠出，並將此裁斷爲顆粒狀後，製得 顆粒狀的光擴散劑母料。 (光擴散性樹脂板之製造） 將經將苯乙烯聚合物（東洋苯乙烯公司製（「東洋苯乙 烯HRM40」、折射率1.5 9)95.0質量份、上述光擴散劑母 料5.0質量份進行摻和所得基底層形成用材料，供給於螺 旋徑40mm的主擠出機，在此，在200至250°C進行加熱 熔融並供給於多支管式模頭（multi-manifold die)(2種3層 分配型）之同時，將上述表面層形成用材料供給於螺旋徑 2 0 mm的輔助濟出機，在此，在190至250 °C進行加熱熔 201011352 融並供給於多支管式模頭（2種3層分配型）。然後，在模 頭溫度25〇至26〇°C下進行共擠壓（co-extruding)之結果， 製得於厚度1.4mm的基底層（2 1)的兩面分別層合有厚度 0.05mm的表面層（22)(22)之3層構成的光擴散性樹脂板 (6)(厚度1.5mm、貪220mm)(參考第1圖）。 (電暈放電處理） 於上述光擴散性樹脂板（6)的一面，使用具備有春日電 機公司製的高頻電源（CT0212型）之電暈放電處理裝置實施 電暈放電處理之結果，製得一面爲電暈放電處理面（6 a)之 光擴散基板（2)(參考第1圖）。該電暈放電處理的線速率 (line speed)，係設定爲l〇m/分鐘。又，進行電暈放電處 理時的施加電力，則設定爲28 0(瓦特）。 <實施例2> 除將電暈放電處理時的施加電力設定爲500W以外， 其餘則按與實施例1同樣方式，製得光擴散基板。 <實施例3> 除將電暈放電處理時的施加電力設定爲7 5 0W以外， 其餘則按與實施例1同樣方式，製得光擴散基板。 <比較例1> 除省略電暈放電處理（作成不實施者）以外，其餘則按 201011352 與實施例1同樣方式，製得光擴散基板。 <實施例4> 經將苯乙烯聚合物（東洋苯乙烯公司製「東洋苯乙烯 HRM40」）100質量份及交聯丙烯酸系聚合物粒子（光擴散 劑、積水化成品工業公司製「MBX2H」、體積平均粒徑 3μπι)6質量份進行乾式摻和後，供給於螺旋徑40mm的擠 出機，在200至25 0°C進行加熱熔融擠出，製得單層的光 擴散性樹脂板（厚度1.5mm、寬220mm)。 於上述光擴散性樹脂板（6)兩面，按與實施例1同採方 式實施電暈放電處理之結果，製得兩面爲電暈放電處理面 (6a)(6a)之光擴散基板（2)(參考第4圖）。電暈放電處理的 條件爲線速率l〇m /分鐘、施加電力爲280W。 <實施例5> 除將電暈放電處理時的施加電力設定爲500W以外， 其餘則按與實施例4同樣方式，製得光擴散基板。 <實施例6> 除將電暈放電處理時的施加電力設定爲750W以外 其餘則按與實施例4同樣方式，製得光擴散基板。 <比較例2> 除省略電暈放電處理（作成不實施者）以外，其餘則按 -20- 201011352 與實施例4同樣方式，製得光擴散基板。 <實施例7> 經將丙烯聚合物（住友化學公司製「諾布連D101」）、 含丙烯單元含有率爲99質量％以上、乙烯單元含有率爲1 質量％以下）1〇〇質量份以及晶核產生劑（ADEKA公司製「 NA11」）〇.〇5質量份進行乾式摻和後，供給於螺旋徑 4 0mm的擠出機，在20 0至25 進行加熱熔融擠出之結果 ，製得單層的光擴散性樹脂板（厚度1.5mm、寬220mm)。 於上述光擴散性樹脂板（6)兩面，按與實施例1同採方 式實施電暈放電處理之結果，製得兩面爲電暈放電處理面 (6a)(6a)之光擴散基板（2)(參考第4圖）。電暈放電處理的 條件爲線速率分鐘、施加電力爲280W。 <實施例8> 除將電暈放電處理時的施加電力設定爲500W以外， 其餘則按與實施例7同樣方式，製得光擴散基板。 <實施例9> 除將電暈放電處理時的施加電力設定爲750W以外， 其餘則按與實施例7同樣方式，製得光擴散基板。 <比較例3> 除省略電暈放電處理（作成不實施者）以外，其餘則按 201011352 與實施例7同樣方式，製得光擴散基板。 <實施例1〇> 經將丙烯聚合物（住友化學公司製「諾布連D101」）、 100.0質量份、聚矽氧橡膠粒子（光擴散劑、東麗•陶康寧 公司製「托列費爾DY33-719」）1.2質量份以及晶核產生 劑（ADEKA公司製「NAU」）0.05質量份進行乾式摻和後 ，供給於螺旋徑40mm的擠壓機，在200至250 °C進行加 熱熔融擠出之結果，製得單層之光擴散性樹脂板（厚度 1.5mm、寬 220mm) 〇 於上述光擴散性樹脂板（6)兩面，按與實施例1同樣方 式實施電暈放電處理之結果，製得兩面爲電景放電處理面 (6a)(6a)之光擴散基板（2)(參考第4圖）。電暈放電處理的 條件爲線速率10m /分鐘，施加電力爲280W。 <實施例1 1> 除將電暈放電處理時的施加電力設定爲5〇〇W以外， 其餘則按與實施例10同樣方式，製得光擴散基板。. <實施例12> 除將電暈放電處理時的施加電力設定爲750W以外， 其餘則按與實施例10同樣方式，製得光擴散基板。 <比較例4 > -22- 201011352 施者）以外，其餘則按 基板。 除省略電暈放電處理（作成不 與實施例1 〇同樣方式，製得光擴 參 參 -23- 201011352 i 實施例3 00 vS 〇 Ο < CN Ο 〇 Os 1 〇 v-i 1 1 1 〇 Ο) ◎ | 1.7χ10ιυ I 寸 〇 〇< 卜 00 On in yn cs 0.3124 I 0.3180 1 實施例2 00 JO ο rn (N ο r—Η CN Ο Ο uS ON 1 〇 1 1 1 〇 σ*Ν Η ◎ | 6-OxlO10 〇 ο 〇〇 cr； wo t> οό ο <N tN 0.3124 0.3179 實施例1 00 o rn (N Ο (N Ο Ο tri 1 〇 yn 1 1 1 § CN »n ◎ 1 4.6χ101ϋ 寸 c> cK Γ ΟΟ ΟΝ m in (N 0.3124 0.3179 比較例1 00 yn 卜 〇 rn (N Ο <N Ο o in ON 1 〇 1 1 1 未處理 OS oo 〇 1 1.2χ101ϋ § VO a； VTi 卜 00 as CN 0.3124 0.3178 苯乙烯-甲基丙烯酸甲酯共聚物(商品名「MS200NT」） |光擴散劑(商品名「XC1A」） 紫外線吸收劑(商品名「LA31」） 加工安定劑(商品名「GP」） /—N 0 1 K 匕 ng 靼 蓉 An m 叢 K) 浒 丙烯聚合物(商品名「D101」） 光擴散劑母料 光擴散劑(商品名「MBX2H」） 光擴散劑(商品名「DY33-719」） 晶核產生劑(商品名「NA11」） 電暈放電處理之施加電力(w) J 光擴散性基板之電暈放電處理面之水接觸角0 塗佈性評價 光擴散板之表面電阻率(Ω/〇) 全光線穿透率(％) 擴散光線穿透率(％) 濁度(％) 黃色度YI 色度X 色度y 表面層之組成 (質量份） 底層之組成 (質量份） 201011352 參 Μ 實施例6 100.0 1 1 6..0 1 1 750 45.6 ◎ l.OxlO10 57.4 56.6 98.6 0.96 0.3109 0.3164 實施例5 100.0 1 1 6..0 1 ) 500 44.2 ◎ 1.9χ1010 57.5 56.7 98.6 0.96 0.3109 0.3164 實施例4 100.0 1 1 6..0 1 官 280 52.5 ◎ -1 1.3x1ο11 -— —-------Π 57.5 56.8 」 98.8 1.03 0.3110 0.3165 比較例2 100.0 1 1 6..0 1 1 未處理 82.2 〇 3.2x109 57.1 56.5 -1 98.9 -1 0.92 0.3109 0.3164 苯乙烯聚合物(商品名「HRM40」） |丙嫌聚合物(商品名「D101」） i光擴散劑母料 i光擴散劑(商品名「MBX2H」） 光擴散劑(商品名「DY33-719」） 晶核產生劑(商品名「NA11」） 電暈放電處理之施加電力(W) 光擴散性基板之電暈放電處理面之水接觸角0 塗佈性評價 光擴散板之表面電阻率(Ω/〇) 全光線穿透率(％) 擴散光線穿透率(％) 濁度(％) 黃色度ΥΙ 色度X 色度y 組成 (質量份） -25- 201011352 s 實施例9 1 「 100.0 1 1 1 0.05 750 rn 00 ◎ 2·5χ1010 85.5 67.6 79.1 1.82 0.3117 0.3175 實施例8 1 100.0 1 1 1 0.05 〇 *0 80.9 ◎ 8.Οχ 109 1 85.5 68.5 80.1 1 1.82 0.3117 _1 0.3175 實施例7 1 100.0 1 1 1 0.05 280 80.7 〇 1·7χ1010 -1 85.7 68.1 79.5 _1 1.82 0.3117 0.3174 比較例3 1 100.0 1 義 1 0.05 未處理 100.4 X 2.6χ109 85.7 67.9 79.2 1.90 0.3117 -1 0.3175 苯乙烯聚合物(商品名「HRM40」） 丙烯聚合物(商品名「D101」） 光擴散劑母料 光擴散劑(商品名「MBX2H」） 光擴散劑(商品名「DY33-719」） 晶核產生劑(商品名「NA11」） 電暈放電處理之施加電力(W) 光擴散性基板之電暈放電處理面之水接觸角(°) 塗佈性評價 光擴散板之表面電阻率(Ω/〇) 全光線穿透率(％) ---—-—-----1 擴散光線穿透率(％) 濁度(％) 黃色度YI 色度X 色度y 組成 (質量份） ^ m m m 201011352 ❿ i 實施例12 1 1 ! 100.0 1 1 0.05 750 82.6 ◎ 8.7xl09 68.4 67.5 98.7 2.48 0.3125 0.3176 實施例11 1 100.0 1 1 0.05 500 83.1 ◎ 6.8χ109 68.7 67.7 98.5 2.46 0.3125 0.3175 實施例10 1 100.0 1 1 CN 0.05 280 79.4 〇 1.3χ1010 68.5 67.4 98.4 2.63 0.3127 0.3177 比較例4 1 100.0 1 1 CSJ 0.05 未處理 98.8 X 1.7χ1010 68.3 67.3 2.38 0.3124 0.3175 苯乙烯聚合物(商品名「HRM40」） 丙烯聚合物(商品名「D101」） 光擴散劑母料 光擴散劑(商品名「MBX2H」） 光擴散劑(商品名「DY33-719」） 晶核產生劑(商品名「NA11」） 電暈放電處理之施加電力(W) 光擴散性基板之電暈放電處理面之水接觸角0 塗佈性評價 光擴散板之表面電阻率(Ω/CD) 全光線穿透率(％) 擴散光線穿透率(％) 濁度(％) 黃色度ΥΙ 色度X 色度y 組成 (質量份） 紘擊煺睐 -27- 201011352 就如上述之方式所得各光擴散基板，依照下述評價法 實施水接觸角之測定及塗佈性之評價。將此等評價結果， 表示於表1至表4中。 <水接觸角之測定法> 準據JIS K6768-1999測定對光擴散基板的電暈放電處 理之純水（蒸餾水）的接觸角。亦即，採用協和界面科學公 司製的接觸角計「CA-X」，依0/2法測定對光擴散基板 的電暈放電處理面之純水的接觸角。 <塗佈性評價法> 將各光擴散基板裁成50mmx50mm的大小，並對此等 光擴散基板試片的電暈放電處理面，滴下抗靜電劑水溶液 (經將日本純藥公司製的四級銨乙基硫酸系抗靜電劑「 SAT-6C」以水稀釋爲100倍之水溶液）約1ml後，將此使 用小型輥輪塗佈裝置加以均勻擴大塗佈。然後，使其自然 乾燥之結果，製得防帶電性光擴散板。根據下述判定基準 ，依目視進行塗佈性之評價。 (判定基準） 「◎」··能涵蓋電暈放電處理面全面加以均勻塗佈 「〇」：略能涵蓋電暈放電處理面全面加以均句塗佈 「X」：未能涵蓋電暈放電處理面全面加以均勻塗佈（部分 性顯著發生有抗靜電劑的塗佈的濃淡不均勻）° -28- 201011352 其次’就如上述方式所得各光擴散板依照下述評價法 進行評價。 將此等評價結果，表示於表1至表4。 <表面電阻率測定法（初期之防帶電性能之評價）> 準據JIS K69 1 1 - 1 955’採用絕緣計（東亞DKK(股）製 、SME-8220)及平板試樣用電極（東亞DKK(股）製、呂]^£· ^ 83 11)以測定光擴散板的表面電阻率（Ω/匚!）。再者，測定前 ，爲狀態調整起見，將測定試料在23°Cx濕度50%RH(相 對濕度）的條件下放置6小時。 <全光線穿透率測定法> 準據JIS K73 6 1 - 1 997，以測定光擴散板的全光線穿透 率 Tt(%)。 φ <擴散光線穿透率測定法> 準據JIS K7136-2000，以測定光擴散板的擴散光線穿 透率Td(%)。 <濁度（clouding value)測定法> 準據JIS K7 1 3 6-2000，以測定光擴散板的濁度（％)。 <依分光穿透率測定之黃色度（yell〇w index)YI、色度x、 色度y之測定> -29- 201011352 採用具備有積分球（integrating sphere)之自動記錄式 分光光度計（automatic recording spectro photometer)(曰立 製作所製「UV-4000」），以測定光擴散板在3 80至78 0nm 的波長範圍的分光穿透率，根據此，分別算出黃色度YI '色度X、色度y。 從表1、表2可知，有關本發明之實施例1至6的光 擴散基板，係在電暈放電處理面的水接觸度爲60°以下者 ，而較未施加電暈放電處理之比較例1、2的光擴散基板 爲改善有塗佈性。於實施例1至6的光擴散基板中，能涵 蓋電暈放電處理全面之方式均勻塗佈抗靜電劑。 從表3、表4可知，有關本發明之實施例7至12的光 擴散基板，係在電暈放電處理面的水接觸角爲90°以下者 ，而較未施加電暈放電處理之比較例3、4的光擴散基板 爲格外改善有塗佈性。於實施例7至12的光擴散基板中 ，能涵蓋電暈放電處理面全面之方式均勻塗佈抗靜電劑。 再者，於實施例7至9、比較例3中，雖係未含有光 擴散劑之構成，惟由於丙烯樹脂係結晶性樹脂而存在有結 晶部分與非晶部分之故，看起來有若干白濁狀，雖未添加 光擴散劑，仍能獲得若平的光擴散性能者。 [產業上之利用可能性] 本發明之光擴散基板，係很適合採用爲直下型背光板 用的光擴散板的製作者，惟並不特別限定於此種用途。又 ，本發明之防帶電光擴散板，係很適合採用爲直下型背光 -30- 201011352 板內的零件者，惟並不特別限定於此種用途。又，本發明 之直下型背光板，係很適合採用爲液晶顯示裝置用者，惟 並不特別限定於此種用途。 【圖式簡單說明】 第1圖：表示有關本發明之光擴散基板之一實施形態 之剖面圖。 @ 第2圖：表示有關本發明之光擴散板之一實施形態之 剖面圖。 第3圖：表示有關本發明之液晶顯示裝置之一實施形 態之模式性剖面圖。 第4圖：表示有關本發明之光擴散基板之其他實施形 態之剖面圖。 【主要元件符號說明】 0 1 :光擴散板 2 :光擴散基板 3 :塗佈層 6 :光擴散性樹脂板 6a:電暈放電處理面 21 :基底層 22 :表面層 30:液晶顯示裝置 31 :直下型背光板 -31 - 201011352 3 2 :光源 33 :光學薄膜 3 4 :燈管箱盒 3 5 :液晶片 3 6 :偏光板 37 :偏光板 38:液晶面板（穿透型影像顯示部） 40 :通氣間隙 50 :空氣層201011352 VI. Description of the Invention: [Technical Field] The present invention relates to a light-diffusing substrate which is suitable for uniformly coating a solution containing an antistatic agent, and is suitable as a uniform anti-strip coating layer. An optical diffusion plate for a direct backlight that can sufficiently prevent adhesion of dust or the like. As used herein, the term "water φ contact angle" means the contact angle of pure water to the surface of a resin sheet as determined by JIS K6768-1 999. (contact angle). [Prior Art] A liquid crystal display device is known as a structure in which a direct type backlight is disposed on the back side of a liquid crystal panel (image display unit). In the above-described direct type backlight, it is known that a plurality of light sources are disposed on an optical reflector, and a light diffusing plate is disposed on the front side of the light source (refer to Patent Document 1: Japan) Patent "Special Publication 2004- 1 7093 7"). In recent years, there has been a rapid increase in the size of liquid crystal display devices, particularly liquid crystal televisions. However, if the number of light sources is increased to increase the size of the screen to ensure sufficient brightness, the amount of heat generated by the light source will be greatly increased. Therefore, when the screen is enlarged, it is necessary to efficiently discharge the heat generated inside. On the direct type backlight device, a fan is provided for the purpose of heat exhaust. The air in the direct type backlight unit is ventilated by the air blower of the exhaust air blower to implement the cooler. However, if the air is blown in this manner -5 - 201011352, there is a problem that the surface of the light diffusing plate is likely to adhere to dust. If dust or the like adheres to the surface of the light diffusing plate, there is a possibility that the image is confusing or the sharpness or brightness of the image is lowered. In order to prevent such dust from adhering, the light diffusing plate needs to have excellent antistatic properties. Therefore, in order to provide the anti-static property of the light-diffusing sheet, there is a proposal to apply an antistatic agent aqueous solution to the surface of the light-diffusing sheet made of synthetic resin, thereby forming an antistatic coating layer on the surface (refer to Patent Document 2). Japanese Patent Laid-Open Publication No. 2006-33 0546, Patent Document 3: Japanese Patent Laid-Open Publication No. Hei. No. 2007- 1874544, and Patent Document 4: Japanese Patent Laid-Open Publication No. 2008- 1 941 1 . SUMMARY OF THE INVENTION However, it has been found by the inventors of the present invention that when the surface of the light diffusing plate made of synthetic resin is coated with an antistatic agent water-liquid, it is easy to cause the aqueous solution of the antistatic agent not to spread uniformly on the surface. In other cases, the unevenness of the antistatic agent 旳 coating tends to occur, and there is a possibility that the dust adhesion is partially insufficient. In particular, when an antistatic agent aqueous solvent is applied to a light diffusion plate made of a propylene polymer, the unevenness of the application of the antistatic agent is remarkably likely to occur. The present invention has been made in view of such a technical background to provide a light-diffusing substrate which is capable of uniformly coating a solution when a solution containing an antistatic agent is applied, and which is difficult to apply unevenness, and which can be pressed The purpose is to cover the anti-charged light diffusing plate in a comprehensive manner to prevent the adhesion of dust. Further, -6-201011352 aims to provide a liquid crystal display device which can display a good image under the dust on the surface of the light diffusing plate. In order to achieve the foregoing objects, the present invention provides the following means. [1] A light-diffusing substrate ‘characterized by applying a corona discharge treatment to at least one surface of a light-diffusing resin sheet containing a transparent resin. [2] The light-diffusing substrate according to the above [1], wherein the transparent resin is a propylene polymer or a styrene polymer. _ [3]. A light diffusing substrate characterized in that a resin containing a propylene polymer forms at least one surface, and a water contact angle of the surface thereof is 90 or less. [4] A light-diffusing substrate characterized in that a resin containing a styrene polymer forms at least one surface, and a water contact angle of the surface thereof is 60 or less 〇 [5] · a light diffusing plate, A coating layer containing an antistatic agent is laminated on the corona discharge treated surface of the light-diffusing substrate described in the above [1] or [2]. Φ [6]. A light-diffusing sheet characterized in that a coating layer containing an antistatic agent is laminated on the surface of the light-diffusing substrate of the above [3] having a water contact angle of 90 or less. [7] A light-diffusing sheet characterized in that a coating layer containing an antistatic agent is laminated on the surface of the light-diffusing substrate of the above [4] having a water contact angle of 60 or less. [8] The light-diffusing sheet according to any one of [5], wherein the coating layer is formed by applying a solution containing an antistatic agent to a light-diffusing substrate and drying. -7-201011352 [9]. The use of a light diffusing plate is the use of light diffusion as described in any one of the above [5] to [8] as a component in a direct type backlight. [10] A light-diffusing sheet according to any one of [5] to [8], wherein the light-diffusing sheet of any one of [5] to [8], and a plurality of light sources disposed on a back side of the light-diffusing sheet. [11] A light-diffusing sheet according to any one of [5] to [8], wherein a plurality of light sources disposed on a back side of the light diffusing plate, and A liquid crystal panel disposed on a front side of the light diffusing plate. In the invention of [1], since at least one of the light-diffusing resin sheets containing a transparent resin is subjected to a corona discharge treatment, if a solution containing an antistatic agent is applied to the corona discharge treatment surface, uniformity is obtained. Coating (that is, suppressing the unevenness of the coating of the antistatic agent), thereby forming a uniform antistatic coating layer, can provide a comprehensive prevention of adhesion of dust and the like in a comprehensive manner. Light diffusing plate. In the invention of [2], the transparent resin is a constituent of a propylene polymer or a styrene polymer, and a solution containing an antistatic agent is applied in a uniform manner because a suitable material can be used as a light diffusing plate ( That is, as a result of suppressing the unevenness of the coating of the antistatic agent, it is possible to form an antistatic coating layer of a uniform sentence, and it is possible to provide a light diffusing plate which can sufficiently prevent adhesion of dust or the like in a comprehensive manner. . In the invention of [3], since the resin containing the propylene polymer forms at least one surface and the water contact angle of the surface thereof is 90 or less, 'if the surface is coated with a solution containing an antistatic agent' It can be uniformly applied (also -8-201011352, that is, the unevenness of the coating of the antistatic agent is inhibited), so that a uniform antistatic coating layer can be formed, and a comprehensive manner can be provided. A light diffusing plate that prevents adhesion of dust or the like. In the invention of [4], since the resin containing the styrene polymer forms at least one surface and the water contact angle of the surface thereof is 60 or less, if the surface is coated with a solution containing an antistatic agent, The coating can be uniformly applied (that is, the unevenness of the coating by the antistatic agent is inhibited), so that a uniform antistatic coating layer can be formed, and a dust can be sufficiently prevented in a comprehensive manner. The attached light diffuser. In the invention of [5], the coating layer containing the antistatic agent is laminated on the corona discharge treated surface of the light-diffusing substrate of the above [1] or [2], and uniform protection is formed. The charged coating layer can sufficiently prevent adhesion of dust or the like to the light diffusion plate in a comprehensive manner. In the invention of [6], the surface of the light-diffusing substrate of the above [3] has a water contact angle of 90 or less, and a coating layer containing an antistatic agent is laminated to form a uniform antistatic coating. The layer can thus sufficiently prevent the adhesion of dust or the like to the light diffusing plate in a comprehensive manner. In the invention of [7], the surface of the light-diffusing substrate of the above [4] has a water contact angle of 60 or less, and a coating layer containing an antistatic agent is laminated to form a uniform antistatic coating. The layer can thus sufficiently prevent the adhesion of dust or the like to the light diffusing plate in a comprehensive manner. In the invention of [8], since the coating layer is applied to the light-diffusing substrate of any of the above [5] to [7] and dried by the coating layer, a coating can be provided. A comprehensive way to fully prevent dust and other 201011352 attached light diffusing panels. In the invention of the above [9], it is possible to provide a member in a direct type backlight panel which is a light diffusing plate which is excellent in antistatic property, which can sufficiently prevent adhesion of dust or the like. In the invention of [10], since the light diffusing plate constituting the direct type backlight is provided with uniform antistatic property in a comprehensive manner, it is possible to ensure high-intensity backlight light in a long-term manner. In the invention of [11], since the light diffusing plate constituting the liquid crystal display device has uniform anti-charge performance in a comprehensive manner, it is possible to display a high-quality and high-quality image in a long-term manner ( That is, the image is not prone to chaotic, sharp and high-brightness images). BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of a light-diffusing substrate (2) according to the present invention is shown in Fig. 1. The light-diffusing substrate (2) is applied to a surface of a light-diffusing resin sheet (6) containing a transparent resin, and a corona discharge processor is applied thereto. That is, one side is a corona discharge treatment surface (6a). In the present embodiment, as the light-diffusing resin sheet (6), a laminate of a facing layer (22) (22) on both sides of a base layer (21) is used. Of course, the above-mentioned light-diffusing resin sheet (6)' may have a structure formed of a single layer (refer to Fig. 4). In addition, in the embodiment, the structure of the light diffusing resin sheet (6) is applied to the one side of the light diffusing resin sheet (6), but it is also applicable to the light diffusing resin sheet (6). It is formed by corona discharge treatment to form a corona discharge treated surface (6a) (6a) (refer to Fig. 4). 201011352 In the light-diffusing substrate (2) having the above configuration, since at least one surface is formed as a corona discharge treated surface (6a), the anti-static coating is applied to the corona discharge treated surface (6a). When the solution of the agent is used, it is possible to suppress the unevenness of the application of the antistatic agent and uniformly apply the coating, and a uniform antistatic coating layer (3) can be formed, thereby providing a comprehensive manner in a comprehensive manner. A light diffusing plate (1) that prevents adhesion of dust or the like (refer to Fig. 2). The condition of the corona discharge treatment is not particularly limited, but is preferably a linear velocity when the light-diffusing resin sheet (6) as the object to be processed passes through the corona discharge field. Line speed) is set at 1 to 20 m/min. Further, it is preferable to set the applied electric power of the corona discharge treatment to 100 to 1 000 W (watt), and particularly preferably set to 150 to 900 W. When the corona discharge treatment is carried out, for example, in the light-diffusing resin sheet (6) containing a propylene polymer, the water contact angle of the surface (corona discharge treated surface) can be made 90 or less. In the light φ diffusing resin sheet (6) containing a styrene polymer, the water contact angle of the surface (corona discharge treated surface) can be made 60 or less. Since the water contact angle of the surface (corona discharge treated surface) can be made small by such corona discharge treatment, it is conceivable that the corona discharge treated surface (6 a) is coated with an antistatic agent. In the solution, it is possible to suppress the unevenness of the application of the antistatic agent and to uniformly coat the coating. It is conceivable that due to the aforementioned corona discharge treatment, a) the surface becomes rough, b) a hydrophilic functional group such as a radical is generated on the surface, and the water contact angle becomes small, but the details are detailed. The role of -11 - 201011352 The institution is not certain. The transparent resin constituting the light-diffusing resin sheet (6) is not particularly limited, and may be exemplified by a polymer, a styrene-based polymer, an acrylonitrile-butadiene-styrene copolymer. , low density polyethylene, high density polyethylene, linear low density polyethylene, acrylonitrile-styrene copolymer, acrylic acid-acrylonitrile-styrene copolymer, methyl methacrylate polymer, methyl methacrylate -styrene copolymer, polyacetal, polyamine, polyethylene terephthalate, polycarbonate, polyfluorene, polyether mill, methylpentene polymer, polyarylate, polyparaphenylene Butylene formate, resin containing an ethylenically unsaturated monomer unit having an alicyclic structure, polyphenylene sulfide, polyphenylene ether, polyether polyketone, etc., general plastics or engineering of these Plastic, etc. The propylene polymer may be a homopolypropylene obtained by separately polymerizing propylene, or a copolymer of propylene and a copolymerizable component copolymerizable therewith. Among them, the propylene polymer is preferably a polymer containing 50% by mass or more of a propylene unit. Further, from the viewpoint of obtaining sufficient rigidity, it is particularly preferable that the content of the propylene unit in the propylene polymer is 98% by mass or more. The copolymerization component is not particularly limited, and examples thereof include an α-olefin such as ethylene or 1-pentene. The styrene polymer may have a styrene unit of 50% by mass or more, preferably 70% by mass or more, as long as it has a styrene unit of 50% by mass or more. a copolymer substituted with an unsaturated monomer unit copolymerized with styrene. The aforementioned monofunctional unsaturated monomer capable of polymerizing with a styryl group may, for example, be methyl methacrylate, butyl methacrylate, methacrylic acid ring-12-201011352 hexyl ester, phenyl methacrylate, Methyl acrylate such as benzyl methacrylate, 2-ethylhexyl methacrylate or 2-hydroxyethyl methacrylate; methyl acrylate, ethyl acrylate, butyl acrylate, cyclohexyl acrylate, acrylic acid Acrylates such as phenyl ester, benzyl acrylate, 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate; unsaturated acids such as methacrylic acid and acrylic acid; methyl styrene, acrylonitrile, methacrylonitrile , maleic anhydride, phenyl maleimide, cyclohexyl maleimide, and the like. Further, the copolymer, ^ may further contain a glutaric acid anhydride unit or a pentaneimine unit. Further, in the above-mentioned polymer or copolymer, a diene rubber "propylene rubber" or the like may be blended as a rubbery polymer. The light-diffusing resin sheet (6) is a resin sheet having a light-diffusing function. For example, if it contains a light-diffusing agent, it can impart a light-diffusing function, but it is not particularly limited to such a method. With light diffusion function. The light-diffusing agent is a particle which exhibits a refractive index different from that of the transparent resin as long as it is incompatible with the transparent resin, and has a function of diffusing the transmitted light after passing through the light φ diffusing plate. (including powder) is not particularly limited. For example, it may be inorganic particles such as glass particles, glass fibers, cerium oxide particles, aluminum hydroxide particles, calcium carbonate particles, barium sulfate particles, titanium oxide particles, or talc, and may be styrene polymer particles or acrylic acid. Organic particles such as polymer particles and siloxane-based polymer particles. In the above light diffusing agent, a volume average particle diameter of 0.5 to 40 μm is usually employed. Here, the volume average particle diameter (d5〇) means that the particle diameter and the volume of the whole particles are measured, and the volume is gradually accumulated from the small particle size, and the cumulative volume can be the total volume of the entire particles. The meaning of the particle size of 50% of the particles. The ratio of dispersing the light-diffusing agent in the transparent resin is preferably in the range of 0.1 to 20 parts by mass of the light-diffusing agent, based on 100 parts by mass of the transparent resin. When the amount is 0.1 part by mass or less, sufficient light diffusion performance can be ensured, and when the amount is 20 parts by mass or less, the impact resistance of the sheet itself can be prevented from being lowered. Next, an embodiment of the light diffusing plate (1) according to the present invention is shown in Fig. 2. The light diffusing plate (1) is attached to a corona discharge treated surface (6a) of the light diffusing substrate (2), and a coating layer (3) containing an antistatic agent is laminated. In the present embodiment, the coating layer (3) is formed by applying a solution containing an antistatic agent to the corona discharge treated surface (6a) of the light-diffusing substrate (2) and drying it. According to the light diffusing plate (1) having the above configuration, the coating layer (3) containing the antistatic agent is laminated on the corona discharge treated surface (6a) of the light diffusing substrate (2). Since a uniform antistatic coating layer is formed, adhesion of dust or the like to the light diffusing plate (1) can be sufficiently prevented in a comprehensive manner. The antistatic agent is not particularly limited, and examples thereof include a cationic antistatic agent, an anionic antistatic agent, and a nonionic antistatic agent. The cationic antistatic agent is not particularly limited, and may, for example, be lauryl trimethylammonium chloride, stearyl trimethylammonium chloride, lauryl diethanolamine or stearylamine hydrochloride. Salt and so on. The anionic antistatic agent is not particularly limited, and examples thereof include alkylphosphoric acid diethylamine amine, potassium alkyl phosphate, and alkylbenzenesulfonate. The above nonionic anti--14-201011352 electrostatic agent is not particularly limited, and examples thereof include polyhydroxyvinyl tridecyl ether, polyhydroxyvinyl lauryl ether, and polyethylene glycol monooleate. , polyhydroxyethylene sorbitan monooleate and the like. The antistatic agent-containing solution for forming the coating layer (3) is not particularly limited, and examples thereof include an aqueous solution containing an antistatic agent and an organic solution containing an antistatic agent. The organic solvent used for the pre-organic solution may, for example, be an alcohol such as ethanol. Among them, from the viewpoint of hygiene or environmental protection, it is preferred to apply the solution containing the antistatic agent to form the coating layer (3). The method for forming the coating layer (3) is not limited, but is preferably formed by coating the solution containing the antistatic agent. The coating method is not particularly limited, and examples thereof include a roll coater method, a lip coating method, and a knife coater method. The concentration of the antistatic agent in the above antistatic agent-containing solution is preferably set to 〇1 to 10% by mass. Further, the amount of the antistatic agent adhered to the coating layer (3) (the amount of the solid component adhered on one side) is preferably set to 〇1 to 5 g/cm2, particularly preferably in the range of 0.05 to 2g/cm2. Further, in the above embodiment (second drawing), the light diffusing plate (1) is configured such that the coating layer (3) is provided only on one surface of the light diffusing substrate (2), but for example, As shown in Fig. 4, the coating layer (3) (3) is provided on the corona discharge treated surface (6a) (6a) on both surfaces of the light-diffusing substrate (2). An embodiment of a liquid crystal display device (30) comprising the above light diffusing plate (1) is shown in Fig. 3. In Fig. 3, (35) is a liquid crystal panel -15-201011352, (36) (37) is a polarizing plate, and (31) is a direct type backlight. A polarizing plate (36) (37) is disposed on each of the upper and lower sides of the liquid crystal panel (35), and a liquid crystal panel is formed by the constituent members (3 5 ) (36) (37). Type image display unit) (38). The backlight panel (31) is disposed on the lower surface side (back surface side) of the lower polarizing plate (37). The backlight panel (31) includes a lamp box (34) having a rectangular shape which is planarly inspected in a rectangular shape and opened on the upper side (front side), and in the lamp box case. a plurality of light sources (32) disposed at a distance from each other, and a light diffusing plate (1) disposed on an upper side (front side) of the plurality of light sources (32), and the light diffusing plate (1) The optical film (33) disposed on the upper side via the air layer (50) (refer to Fig. 3). The light diffusing plate (1) is disposed between the vicinity of the lamp box case (34) and the lamp box case (34) in a state in which a venting gap (40) is formed. Further, a light reflecting layer is provided on the inner surface of the bulb case (34). Further, an exhauster (not shown) for discharging the air in the above-mentioned lamp box casing (34) is attached. In the liquid crystal display device (30) according to the above configuration, since the exhaust air is exhausted from the inside of the lamp box case (34) by using the exhaust fan (40), the backlight can be efficiently discharged. (31) fever. At this time, dust or the like may also intrude into the lamp box case (34) due to the ventilation inside the lamp box case (34), but the light diffusing plate disposed adjacent to the lamp box case (34) (1) Since the coating layer (3) containing an antistatic agent is formed on the surface (the surface on the side of the lamp box box), the light diffusion (1) surface (the side surface of the lamp box box) can be covered. A comprehensive way to prevent dust from adhering, the LCD-16-201011352 display unit (30) can display high-quality and high-quality images for a long time. Further, the light source (32) is not particularly limited, and examples thereof include a fluorescent tube, a halogen lamp, a tungsten lamp, and a light-emitting diode. The light-diffusing substrate (2), the light-diffusing sheet (1), the direct-type backlight (31), and the liquid crystal display device (30) according to the present invention are not particularly limited by the above embodiments, and The scope of the patent application without departing from its spirit may allow for any design change. [Embodiment] [Embodiment] Next, a specific embodiment of the present invention will be described, but the present invention is not particularly limited by the examples. <Example 1> (Production of material for forming a surface layer) Φ A styrene-methyl methacrylate copolymer (Estrit MS200NT manufactured by Nippon Steel Chemical Co., Ltd.) and a styrene unit of 80% by mass were used. Methyl methacrylate unit 20% by mass, MFR (melt flow rate) 1.3 to 1.9 g/10 minutes) 7 5.8 parts by mass, crosslinked acrylic polymer particles (light diffusing agent, Sumitomo Chemical Co., Ltd. (XC1A", volume average particle diameter: 30 μm), 23.0 parts by mass, ultraviolet absorbing agent ("LA31" manufactured by Adeka Co., Ltd.), 1.0 part by mass, and processing stabilizer (0.2 parts by mass of Sumitomo Chemical Co., Ltd.) After dry blending, it was placed in a twin-screw extruder with a screw diameter of 65 mm, and it was kneaded by heating and melting at 200 to 260 ° C and extruded in a strand shape at -17-201011352 and cut this into After the pellet shape, a granular surface layer forming material is obtained. (Manufacture of a light diffusing masterbatch for a base layer) A styrene polymer (Toyo Benzene Co., Ltd. Ethylene HRM40", refractive index 1.59, MFR0.9 to (12 g/10 min), 52 parts by mass of crosslinked acrylic polymer particles (light diffusing agent, "Summer Chemical Co., Ltd." "Summer Pike XC1A") 40 parts by mass, polyoxyn rubber particles (light diffusing agent, east 4 parts by mass of "Torefel DY3 3-719", volume average particle size 2μιη), 2 parts by mass of UV absorber ("Sumei Plastics 200" by Sumitomo Chemical Co., Ltd.) and processing stabilizer (2 parts by mass of Sumitomo Chemical Co., Ltd.), which was dry blended, placed in a twin-screw extruder with a screw diameter of 65 mm, and heated and melted at 80 to 250 °C. After linear extrusion and cutting into pellets, a pelletized light diffusing agent masterbatch is prepared. (Manufacture of light diffusing resin sheet) Styrene polymer (made by Toyo Styrene Co., Ltd.) a base layer forming material obtained by blending styrene HRM 40", a refractive index of 1.5 9), 95.0 parts by mass, and 5.0 parts by mass of the above light diffusing agent master batch, and supplying the material to a main extruder having a spiral diameter of 40 mm, here, at 200 to Heated and melted at 250 ° C and supplied to a manifold mold (m Ulti-manifold die) (the two types of three-layer distribution type), the above-mentioned surface layer forming material is supplied to an auxiliary chip machine having a spiral diameter of 20 mm, and here, the heating is melted at 190 to 250 ° C. And it is supplied to a multi-tubular die (two types of 3-layer distribution type). Then, the result of co-extruding at a die temperature of 25 〇 to 26 ° C is obtained to a thickness of 1.4 mm. A light diffusing resin plate (6) (thickness: 1.5 mm, greedy 220 mm) composed of three layers of a surface layer (22) (22) having a thickness of 0.05 mm is laminated on both surfaces of the base layer (2 1) (refer to the first Figure). (corona discharge treatment) The corona discharge treatment device equipped with a high-frequency power source (CT0212 type) manufactured by Kasuga Electric Co., Ltd. was used to perform a corona discharge treatment on one surface of the light-diffusing resin sheet (6). One side is a light diffusion substrate (2) of the corona discharge treatment surface (6 a) (refer to Fig. 1). The line speed of the corona discharge treatment was set to l〇m/min. Further, the applied electric power at the time of the corona discharge treatment was set to 28 0 (watt). <Example 2> A light-diffusing substrate was obtained in the same manner as in Example 1 except that the applied electric power at the time of the corona discharge treatment was changed to 500 W. <Example 3> A light-diffusing substrate was obtained in the same manner as in Example 1 except that the applied electric power at the time of the corona discharge treatment was set to 750 W. <Comparative Example 1> A light-diffusing substrate was produced in the same manner as in Example 1 except that the corona discharge treatment (which was not performed) was omitted. <Example 4> 100 parts by mass of styrene polymer (Toyo Styrene HRM40, manufactured by Toyo Co., Ltd.) and crosslinked acrylic polymer particles (light diffusing agent, "MBX2H" manufactured by Sekisui Kogyo Co., Ltd. 6 parts by mass of a volume average particle diameter of 3 μm, and dry blending, and then supplied to an extruder having a spiral diameter of 40 mm, and heat-melt-extruded at 200 to 250 ° C to obtain a single-layer light-diffusing resin sheet ( Thickness 1.5mm, width 220mm). On both sides of the light-diffusing resin sheet (6), the corona discharge treatment was carried out in the same manner as in Example 1, and a light-diffusing substrate (2) having a corona discharge treatment surface (6a) (6a) on both sides was obtained. (Refer to Figure 4). The conditions of the corona discharge treatment were a linear velocity of l 〇 m / min and an applied electric power of 280 W. <Example 5> A light-diffusing substrate was obtained in the same manner as in Example 4 except that the applied electric power at the time of the corona discharge treatment was changed to 500 W. <Example 6> A light-diffusing substrate was obtained in the same manner as in Example 4 except that the applied electric power at the time of the corona discharge treatment was changed to 750 W. <Comparative Example 2> A light-diffusing substrate was produced in the same manner as in Example 4 except that the corona discharge treatment (which was not performed) was omitted. <Example 7> A propylene polymer ("Noble D101" manufactured by Sumitomo Chemical Co., Ltd.), a propylene-containing unit content of 99% by mass or more, and an ethylene unit content of 1% by mass or less) of 1 part by mass And a nucleating agent ("NA11" manufactured by Adeka Co., Ltd.), 5 parts by mass, dry blended, and then supplied to an extruder having a spiral diameter of 40 mm, and subjected to hot melt extrusion at 20 to 25 A single-layer light diffusing resin sheet (thickness: 1.5 mm, width: 220 mm) was obtained. On both sides of the light-diffusing resin sheet (6), the corona discharge treatment was carried out in the same manner as in Example 1, and a light-diffusing substrate (2) having a corona discharge treatment surface (6a) (6a) on both sides was obtained. (Refer to Figure 4). The conditions of the corona discharge treatment were a line rate of minutes and an applied electric power of 280 W. <Example 8> A light-diffusing substrate was obtained in the same manner as in Example 7 except that the applied electric power at the time of the corona discharge treatment was changed to 500 W. <Example 9> A light-diffusing substrate was obtained in the same manner as in Example 7 except that the applied electric power at the time of the corona discharge treatment was changed to 750 W. <Comparative Example 3> A light-diffusing substrate was produced in the same manner as in Example 7 except that the corona discharge treatment (which was not performed) was omitted. <Example 1〇> A propylene polymer ("Noble D101" manufactured by Sumitomo Chemical Co., Ltd.), 100.0 parts by mass, and a polyoxyxylene rubber particle (light diffusing agent, Toray Dow Corning Co., Ltd.) 1.2 parts by mass of Fe DY33-719") and 0.05 parts by mass of a crystal nucleating agent ("NAU" manufactured by Adeka Co., Ltd.) were dry blended, and then supplied to an extruder having a spiral diameter of 40 mm and heated at 200 to 250 °C. As a result of the melt extrusion, a single-layer light-diffusing resin sheet (thickness: 1.5 mm, width: 220 mm) was formed on both surfaces of the above-mentioned light-diffusing resin sheet (6), and corona discharge treatment was carried out in the same manner as in Example 1. As a result, a light-diffusing substrate (2) having both sides of the electric-field discharge treatment surface (6a) (6a) was obtained (refer to Fig. 4). The corona discharge treatment was carried out under the conditions of a line rate of 10 m / min and an applied electric power of 280 W. <Example 1 1> A light-diffusing substrate was obtained in the same manner as in Example 10 except that the applied electric power at the time of the corona discharge treatment was set to 5 Å. . <Example 12> A light-diffusing substrate was obtained in the same manner as in Example 10 except that the applied electric power at the time of the corona discharge treatment was changed to 750 W. <Comparative Example 4 > -22- 201011352 The other is the substrate. Except that the corona discharge treatment was omitted (the same procedure as in Example 1 was carried out, the optical expansion was carried out. Reference -23-201011352 i Example 3 00 vS 〇 Ο < CN Ο 〇 Os 1 〇 v-i 1 1 1 〇 Ο) ◎ | 1.7χ10ιυ I inch 〇 〇 < 00 On in yn cs 0.3124 I 0.3180 1 Embodiment 2 00 JO ο rn (N ο r — Η CN Ο Ο uS ON 1 〇 1 1 1 〇σ*Ν ◎ ◎ | 6-OxlO10 〇ο 〇〇cr ; wo t> οό ο <N tN 0.3124 0.3179 Example 1 00 o rn (N Ο (N Ο Ο tri 1 〇yn 1 1 1 § CN »n ◎ 1 4.6χ101ϋ inch c> cK Γ ΟΟ ΟΝ m in (N 0.3124 0.3179 Comparative Example 1 00 yn 卜〇rn (N Ο <N Ο o in ON 1 〇1 1 1 Untreated OS oo 〇1 1.2χ101ϋ § VO a; VTi 00 as CN 0.3124 0.3178 Styrene-methyl methacrylate copolymer (trade name "MS200NT") | Diffusion agent (trade name "XC1A") UV absorber (trade name "LA31") Process stabilizer (product name "GP") /—N 0 1 K 匕ng Cistanche An m Cong K) Phenyl propylene polymer (product) Name "D101") Light diffusing agent masterbatch light diffusing agent (trade name "MBX2H") Light diffusing agent (trade name "DY33-719") Crystal nucleating agent (trade name "NA11") Applied electric power by corona discharge treatment (w) Water contact angle of corona discharge treated surface of J light diffusing substrate 0 Coating property evaluation Surface resistivity of light diffusing plate (Ω/〇) Total light transmittance (%) Diffusion light transmittance (% ) Turbidity (%) Yellowness YI Chroma X Chromaticity y Composition of surface layer (parts by mass) Composition of the bottom layer (parts by mass) 201011352 Reference Example 6 100.0 1 1 6..0 1 1 750 45.6 ◎ l. OxlO10 57.4 56.6 98.6 0.96 0.3109 0.3164 Example 5 100.0 1 1 6..0 1 ) 500 44.2 ◎ 1.9χ1010 57.5 56.7 98.6 0.96 0.3109 0.3164 Example 4 100.0 1 1 6..0 1 Officer 280 52.5 ◎ -1 1.3x1ο11 -————-------Π 57.5 56.8 ” 98.8 1.03 0.3110 0.3165 Comparative Example 2 100.0 1 1 6..0 1 1 Untreated 82.2 〇3.2x109 57.1 56.5 -1 98.9 -1 0.92 0.3109 0.3164 Styrene polymer (trade name "HRM40") | propylene polymer (trade name "D101") i light diffusing agent masterbatch i light diffusing agent ( Product name "MBX2H") Light diffusing agent (trade name "DY33-719") Crystal nucleating agent (trade name "NA11") Applied electric power by corona discharge treatment (W) Corona discharge treatment surface of light diffusing substrate Water contact angle 0 Coating property evaluation Surface resistivity of light diffusing plate (Ω/〇) Total light transmittance (%) Diffusion light transmittance (%) Turbidity (%) Yellowness ΥΙ Chroma X chromaticity y Composition (parts by mass) -25- 201011352 s Example 9 1 "100.0 1 1 1 0.05 750 rn 00 ◎ 2·5χ1010 85.5 67.6 79.1 1.82 0.3117 0.3175 Example 8 1 100.0 1 1 1 0.05 〇*0 80.9 ◎ 8.Οχ 109 1 85.5 68.5 80.1 1 1.82 0.3117 _1 0.3175 Example 7 1 100.0 1 1 1 0.05 280 80.7 〇1·7χ1010 -1 85.7 68.1 79.5 _1 1.82 0. 3117 0.3174 Comparative Example 3 1 100.0 1 Meaning 1 0.05 Untreated 100.4 X 2.6χ109 85.7 67.9 79.2 1.90 0.3117 -1 0.3175 Styrene polymer (trade name "HRM40") Propylene polymer (trade name "D101") Light diffusing agent Light diffusing agent (trade name "MBX2H") Light diffusing agent (trade name "DY33-719") Crystal nucleating agent (trade name "NA11") Applied power by corona discharge treatment (W) Electricity of light diffusing substrate Water contact angle of the halo discharge surface (°) Applicability evaluation Surface resistivity of the light diffusing plate (Ω/〇) Total light transmittance (%) -----------1 Diffusion light penetration Permeability (%) Turbidity (%) Yellowness YI Chroma X Chromaticity y Composition (parts by mass) ^ mmm 201011352 ❿ i Example 12 1 1 ! 100.0 1 1 0.05 750 82.6 ◎ 8.7xl09 68.4 67.5 98.7 2.48 0.3125 0.3176 Example 11 1 100.0 1 1 0.05 500 83.1 ◎ 6.8 χ 109 68.7 67.7 98.5 2.46 0.3125 0.3175 Example 10 1 100.0 1 1 CN 0.05 280 79.4 〇1.3χ1010 68.5 67.4 98.4 2.63 0.3127 0.3177 Comparative Example 4 1 100.0 1 1 CSJ 0.05 Untreated 98.8 X 1.7χ1010 68.3 67.3 2.38 0.3124 0.3175 benzene Ethylene polymer (trade name "HRM40") propylene polymer (trade name "D101") Light diffusing agent masterbatch light diffusing agent (trade name "MBX2H") Light diffusing agent (trade name "DY33-719") Agent (trade name "NA11") Applied electric power by corona discharge treatment (W) Water contact angle of corona discharge treatment surface of light diffusing substrate 0 Coating property evaluation Surface resistivity of light diffusing plate (Ω/CD) Light transmittance (%) Diffusion light transmittance (%) Turbidity (%) Yellowness ΥΙ Color X chromaticity y Composition (mass parts) 纮 煺 煺 -27- 201011352 The light obtained as described above The diffusion substrate was subjected to measurement of the water contact angle and evaluation of the coatability in accordance with the following evaluation method. The results of these evaluations are shown in Tables 1 to 4. <Measurement method of water contact angle> The contact angle of pure water (distilled water) to the corona discharge treatment of the light-diffusing substrate was measured in accordance with JIS K6768-1999. Namely, the contact angle of the pure water of the corona discharge treated surface of the light-diffusing substrate was measured by the 0/2 method using a contact angle meter "CA-X" manufactured by Kyowa Interface Science Co., Ltd. <Applicability Evaluation Method> Each of the light-diffusing substrates was cut into a size of 50 mm x 50 mm, and an antistatic agent aqueous solution was dropped on the corona discharge treated surface of the light-diffusing substrate test piece (manufactured by Nippon Pure Chemical Co., Ltd.) After the quaternary ammonium ethyl sulfate-based antistatic agent "SAT-6C" was diluted with water to a ratio of 100 times, about 1 ml, the coating was uniformly spread using a small roller coating device. Then, as a result of natural drying, an antistatic photo-diffusing sheet was obtained. The evaluation of the coating property was carried out visually according to the following criteria. (Criteria for Judgment) "◎"·· can cover the corona discharge treatment surface and apply it uniformly. “〇”: It can cover the corona discharge treatment surface and apply the same sentence “X”: it cannot cover the corona discharge treatment. The surface was uniformly coated uniformly (partially significant unevenness in the application of the antistatic agent). -28-201011352 Next, each of the light-diffusing sheets obtained as described above was evaluated in accordance with the following evaluation method. The results of these evaluations are shown in Tables 1 to 4. <Surface resistivity measurement method (Evaluation of initial antistatic property)> JIS K69 1 1 - 1 955' is an insulation meter (made by East Asia DKK Co., Ltd., SME-8220) and an electrode for a flat sample ( East Asia DKK (share) system, Lv] ^ £ · ^ 83 11) to determine the surface resistivity of the light diffuser (Ω / 匚!). Further, before the measurement, for the state adjustment, the measurement sample was allowed to stand under the conditions of 23 ° C x humidity 50% RH (relative humidity) for 6 hours. <Total Light Transmittance Measurement Method> The total light transmittance Tt (%) of the light diffusing plate was measured in accordance with JIS K73 6 1 - 997. Φ <Determination of diffused light transmittance> The diffusion light transmittance Td (%) of the light diffusing plate was measured in accordance with JIS K7136-2000. <Measurement method of clouding value> The turbidity (%) of the light diffusing plate was measured in accordance with JIS K7 1 3 6-2000. <Measurement of yellowness (yell〇w index) YI, chromaticity x, and chromaticity y according to the fractional light transmittance> -29- 201011352 Using an automatic recording spectrophotometer having an integrating sphere (automatic recording spectro photometer) ("UV-4000" manufactured by Seiko Seisakusho Co., Ltd.), in order to measure the spectral transmittance of the light diffusing plate in the wavelength range of 380 to 78 nm, and calculate the yellowness YI 'chromaticity X, respectively. And chroma y. As can be seen from Tables 1 and 2, the light-diffusing substrates according to Examples 1 to 6 of the present invention are those in which the water contact degree on the corona discharge treated surface is 60 or less, and the comparative example in which no corona discharge treatment is applied. The light-diffusing substrate of 1, 2 is improved in coatability. In the light-diffusing substrates of Examples 1 to 6, the antistatic agent can be uniformly coated in a manner that covers the entire corona discharge treatment. As can be seen from Tables 3 and 4, the light-diffusing substrates according to Examples 7 to 12 of the present invention are those in which the water contact angle on the corona discharge treated surface is 90 or less, and the corona discharge treatment is not applied. The light diffusing substrates of 3 and 4 are particularly improved in applicability. In the light-diffusing substrate of Examples 7 to 12, the antistatic agent can be uniformly coated in such a manner that the corona discharge treatment surface is comprehensive. In addition, in Examples 7 to 9 and Comparative Example 3, although the composition of the light diffusing agent was not contained, the crystalline portion and the amorphous portion were present due to the acryl resin-based crystalline resin, and it appeared that there was some white turbidity. In the shape, although no light diffusing agent is added, the light diffusing performance of the flat can be obtained. [Industrial Applicability] The light-diffusing substrate of the present invention is suitably used as a creator of a light-diffusing sheet for a direct-type backlight, but is not particularly limited to such use. Further, the antistatic optical diffusing plate of the present invention is suitable for use as a component in a direct type backlight -30-201011352, but is not particularly limited to such use. Further, the direct type backlight of the present invention is suitably used as a liquid crystal display device, but is not particularly limited to such use. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a cross-sectional view showing an embodiment of a light-diffusing substrate according to the present invention. @ Fig. 2 is a cross-sectional view showing an embodiment of a light diffusing plate of the present invention. Fig. 3 is a schematic cross-sectional view showing an embodiment of a liquid crystal display device of the present invention. Fig. 4 is a cross-sectional view showing another embodiment of the light-diffusing substrate of the present invention. [Description of main component symbols] 0 1 : Light diffusing plate 2: Light diffusing substrate 3: Coating layer 6: Light diffusing resin plate 6a: Corona discharge treated surface 21: Base layer 22: Surface layer 30: Liquid crystal display device 31 : Direct type backlight panel - 31 - 201011352 3 2 : Light source 33 : Optical film 3 4 : Lamp box box 3 5 : Liquid crystal panel 3 6 : Polarizing plate 37 : Polarizing plate 38 : Liquid crystal panel (transmissive image display unit) 40: Ventilation gap 50: air layer
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