200921204 九、發明說明 【發明所屬之技術領域】 本發明有關於一種適用於液晶顯示器用光源 幕中使用之光擴散薄片或防眩薄膜等之光擴散薄 是不損及原本性能而可實現提高印刷適性或加工 散薄膜。 【先前技術】 具備光擴散性之光學薄膜大多使用於液晶顯 幕等。例如，於液晶顯示器之光源裝置，於用以 源之光轉變爲平面狀光之導光板上（光射出側）， 以實現使來自光源之光均一化之光擴散薄片。 上，大多配置有使自導光板射出之光朝向前方之 之透鏡薄片，此情況下，亦有在透鏡薄片上配置 鏡等之圖型不被看到之光擴散薄片之情況。 配置在透鏡薄片上之光擴散薄片由於與配置 上之光擴散薄片所要求之光學特性不同，故有時 爲「上部用」，後者稱爲「下部用」。具體而言 之光擴散薄片由於係用以提高亮度之薄膜，故有 霧濁度亦高之要求。另一方面，上部用之光擴散 目的係抑制透鏡之眩眼或隱蔽透鏡之瑕疵，故要 (圖像清晰性）低。 已實用化之多數光擴散薄膜，具備有於黏合 分散顏料或樹脂粒等之光擴散劑之光擴散層，作 裝置及螢 膜，尤其 性之光擴 示器或螢 使來自光 設置有用 於導光板 稜鏡片等 用以使稜 在導光板 前者亦稱 ，下部用 売度局且 薄片，其 求清晰度 劑樹脂中 爲黏合劑 -4- 200921204 樹脂則使用熱硬化型樹脂或電離輻射線硬化型樹脂（專利 文獻1、專利文獻2)。電離輻射線硬化型樹脂，相較於熱 硬化型樹脂，其霧濁度、清晰度、亮度之平衡調整較容 易，例如，使用於液晶顯示器之光擴散薄片時，可容易地 分別滿足下部用與上部用之要求特性。 [專利文獻1]特開2006- 5 845 3號公報 [專利文獻2 ]特開2 0 0 2 - 9 8 8 0 9號公報 【發明內容】 [發明欲解決的課題] 光擴散薄片係對應於用途切斷成適當大小後使用。又 有依據用途而在表面上施以印刷之情況。例如，於上述液 晶顯示器中使用之上部用光擴散薄片，爲防止自液晶顯示 畫面端部洩露光而有對光擴散薄片之端部全面施加邊框印 刷之情況。 將此等切斷加工或印刷之際，使用電離輻射線硬化型 樹脂作爲黏合劑樹脂所得之光擴散薄片，有切斷時易有切 屑產生的問題或有印刷油墨之接著性變差的問題。使用熱 硬化型樹脂作爲黏合劑樹脂所得之光擴散薄片，雖可減低 該等問題，但霧濁度、清晰度、亮度之平衡變困難。尤 其，於要求清晰度低且亮度高之上部用光擴散薄片中，於 添加光擴散劑以其成爲適當霧濁度及亮度之情況時，清晰 度過高，無法抑制透鏡薄片之眩眼。相反地，若使清晰度 低時，將產生亮度也隨之降低之問題。 -5- 200921204 本發明爲解決上述問題，提供一種加工時切屑之發 少、且與印刷油墨之接著性良好，且具備作爲光擴散薄 之特性之光擴散薄膜爲目的。 [用以解決問題之手段] 爲解決上述問題，本發明人等對於使用熱硬化型樹 作爲黏合劑樹脂之光擴散層的改良積極硏究之結果，發 於光擴散層中添加於分子中不含有親水性基之液狀或膏 之氟系添加劑時，可不損及熱硬化型樹脂所具有之印刷 性或截斷適性，而可獲得所需亮度及清晰度，尤其是可 現亮度提高及抑制清晰度，因而完成本發明。 亦即，本發明之光擴散薄膜，係具備含有黏合劑樹 及光擴散劑之光擴散層，其特徵爲該黏合劑樹脂含有熱 化型樹脂及於分子中不含有親水性基之氟系添加劑。 又，本發明之光擴散薄膜之特徵爲上述氟系添加劑 分子中含有至少1個氟烷基及至少1個醚鍵。 又，本發明之光擴散薄膜之特徵爲上述光擴散層含 相對於黏合劑樹脂1 00重量份爲20重量份以上、60重 份以下之光擴散劑，且光擴散薄膜之霧濁度爲3 0%以上 未達5 0 %。 又，本發明之光擴散薄膜之特徵爲上述氟系添加劑 對於上述黏合劑樹脂100重量份含有3重量份以上、 重量份以下。 本發明之光源裝置之特徵爲使用上述光擴散薄膜者 生 片 脂 現 狀 適 實 脂 硬 於 有 量 相 -6 - 15 200921204 亦即，本發明之光源裝置係具備有光源、配置於接近上述 光源用以導光或光擴散之光學板、配置於上述光學板光射 出側之透鏡薄片、配置於與上述透鏡薄片之光射出側相反 側及/或上述透鏡薄片之光射出側之光擴散薄片，其特徵 爲上述光擴散薄片爲本發明之光擴散薄膜。 又，本發明之光源裝置係具備有光源、配置於接近上 述光源用以導光或光擴散之光學板、配置於上述光學板光 射出側之透鏡薄片、配置於與上述透鏡薄片之光射出側相 反側之第1光擴散薄片、及配置於上述透鏡薄片之光射出 側之第2光擴散薄片，其特徵爲上述第2光擴散薄片爲本 發明之光擴散薄膜。 又，本發明之光源裝置其特徵爲上述第1光擴散薄片 之霧濁度爲80〜95%，清晰度爲5〜20%，上述第2光擴散 薄片之霧濁度爲30~50%，清晰度爲20〜35%。 【實施方式】 以下，就本發明之光擴散薄膜之實施形態加以說明。 首先本發明之光擴散薄膜構造示於圖1。本發明之光 擴散薄膜10，如圖1(a)所示，可爲由光擴散層11之單層 所構成者，亦可如圖1(b)所示，在支持體12上設置光擴 散層1 1者。 作爲支持體12’只要是光透過率高、透明性優異之 材料即可，並無特別限制，舉例有例如聚對苯二甲酸乙二 醇酯、聚萘二甲酸乙二醇酯等之聚酯系樹脂；二乙醯纖維 200921204 素、三乙醯纖維素等之纖維素系樹脂；聚碳酸酯系樹脂； 聚甲基丙烯酸甲酯等之丙烯酸系樹脂等。 支持體1 2之與設有光擴散層Η之側相反之該側上較 好設有用以防止光擴散薄膜捲曲且提高耐擦傷性之背塗層 13(圖1(c))等。本發明之光擴散薄膜作爲背光裝置之上部 用光擴散薄膜而使用時，光擴散層11(有凹凸之面）係配置 於光射出側，其相反側成爲與透鏡薄片相接。藉由於與此 透鏡薄片相接之面上設置耐擦傷性之背塗層1 3，可防止 傷痕發生。至於構成背塗層1 3之材料，較好使用與後述 之光擴散層1 1之黏合劑樹脂同樣的樹脂。 支持體1 2之厚度並無特別限制，但使用作爲背光裝 置之上部用光擴散薄片時，較好爲12〜2 50μιη。 接著對光擴散薄膜之光擴散層1 1加以說明。光擴散 層基本上是由黏合劑樹脂與光擴散劑所構成。 作爲黏合劑樹脂，主要使用熱硬化型樹脂。藉由使用 熱硬化型樹脂’可保有高的硬度，且相比於電離輻射線硬 化型樹脂時，於機械加工時之加工時切屑的發生少，可提 高印刷適性。因此，本發明之光擴散薄膜使用作爲背光裝 置之上部用光擴散薄片時，可固著性良好地施加邊框印 刷。 作爲熱硬化型樹脂，可使用尿素樹脂、三聚氰胺樹 脂、酣樹脂、環氧樹脂、不飽和聚酯樹脂 '醇酸樹脂、胺 基甲酸醋樹脂、丙烯酸系樹脂、聚胺基甲酸酯、氟系樹 脂、砂氧樹脂以及聚醯亞胺等公知之熱硬化型樹脂，尤其 -8- 200921204 是透明性及硬度高者最好。具體而言，較好爲由丙烯酸多 元醇與異氰酸酯反應而得之丙烯酸系樹脂、由聚酯多元醇 與異氰酸酯反應而得之聚酯樹脂。又硬化後之硬度，較好 爲鉛筆硬度Η以上。 黏合劑樹脂係上述熱硬化型樹脂含量爲該黏合劑樹脂 之至少80重量％以上，更好90重量％以上。除了熱硬化 型樹脂以外，爲了改善印刷適性、截斷性，亦可含有丙烯 酸系樹脂、聚酯系樹脂等之熱可塑性樹脂。 進而該光擴散層，除了黏合劑樹脂以外，亦含有分子 中不含有親水性基之氟系添加劑。藉由使用熱硬化型樹脂 作爲黏合劑樹脂且添加分子中不含有親水性基之氟系添加 劑，可如使用電離輻射線硬化型樹脂之情況同樣地，於層 表面上發生「起伏」（不僅單是光擴散劑從表面突出所形 成之凸部，且使其周圍之黏合劑樹脂之層鼓起之現象）， 可發生有效的光擴散性。藉此，可獲得不使亮度降低但抑 制清晰度（圖像清晰性）爲低之效果。藉由於以如此熱硬化 型樹脂作爲主成分之黏合劑樹脂中添加上述氟系添加劑， 可獲得僅以熱硬化型樹脂難以達成之平衡良好的光學特 性，亦即可獲得良好霧濁度、低的清晰度且具有亮度。 進而藉由利用上述之「起伏」發生，光擴散劑之添加 量可減少。 作爲氟系添加劑，係使用於分子中導入有1個以上氟 烷基之寡聚物。如此之寡聚物於添加前之狀態爲液狀或膏 狀。又，使用於氟系添加劑分子中不含有磺酸基、羧酸基 -9- 200921204 等之親水性基者。於分子中含有親水性基之氟系添加劑難 以減低清晰度。因此作爲上部用光擴散薄片時，成爲可辨 識到配置於下側之稜鏡薄片圖型。 又較好爲與黏合劑樹脂之相溶性良好者。藉由使用與 黏合劑樹脂之相溶性良好者，可有效地發生「起伏」。 使用丙烯酸系樹脂、聚酯系樹脂作爲黏合劑樹脂時， 最好爲含有醚鍵之寡聚物。具體而言，較好爲具有碳數 C3〜C12之全氟烷基之聚氧乙烯醚。 上述氟系添加劑之含量隨著光擴散劑添加量而異，若 光擴散劑之添加量多’則液狀或膏狀之氟系添加劑含量亦 有必要變多。作爲一例，相對於黏合劑樹脂1 00重量份， 光擴散劑之添加量爲4 0重量份以下時，相對於黏合劑樹 脂1 0 0重量份，氟系添加劑較好爲3重量份以上、1 5重 量份以下’更好爲5重量份以上、1 〇重量份以下。藉由 使添加量成爲3重量份以上，可降低清晰度，且藉由成爲 15重量份以下’可保有亮度在適度範圍。 作爲添加於光擴散層之光擴散劑，使用有丙烯酸樹 脂、聚胺基甲酸酯、聚氯化乙烯、聚苯乙烯、聚醯胺、聚 碳酸酯等之樹脂珠粒。尤其較好爲丙烯酸樹脂、聚苯乙 烯。樹脂珠粒之平均粒徑較好爲1〜20μιη，更好爲 3〜;I 0 μ m。由其使用作爲上部用光擴散薄片時，平均粒徑 爲ΙΟμπι以下’較好不含有最大粒徑3〇μιη以上之粒子。 係由於30μιη以上之粒子會被辨識成異物之故。 光擴散層中樹脂珠粒之含量隨光擴散薄膜之用途而 -10- 200921204 異，但使用作爲上部用光擴散薄片時，比使用作爲下部用 光擴散薄片時少，相對於黏合劑樹脂1 00重量份，爲 20〜60重量份左右，較好爲25〜60重量份。又使用作爲防 眩性薄膜等之光擴散性薄膜時，爲5〜1 5重量份左右。 光擴散層除了以上述熱硬化型樹脂作爲主成分之黏合 劑樹脂、液狀或膏狀氟系添加劑以及樹脂珠粒以外，在不 阻礙該等特性之範圍內，可添加紫外線吸收劑等之添加 劑。光擴散層之厚度並無特別限制，但通常爲5〜15 μιη。 本發明之光擴散薄膜可藉由將於構成光擴散層之材料 中添加適宜溶劑而調製之塗佈液，以習知塗佈方法塗佈於 支持體上，經加熱硬化而製得。或者亦可藉由押出成型等 使構成光擴散層之材料加工成薄膜狀。 接著對使用本發明之光擴散薄膜之光源裝置之一實施 形態加以說明。圖2爲顯示使用本發明之光擴散薄膜之光 源裝置之一例圖。圖中所示之光源裝置20係側光（edge-light)方式之背光裝置，具備有光源21、導光板22、設置 於其上之下部用光擴散薄片23、用以使導光板22之光朝 向上部之透鏡薄片24、及設置於透鏡薄片24上之上部用 光擴散薄片2 5。 所謂透鏡薄片，係對入射之光具有特定集光特性或折 射特性者，除了具有特定頂角之稜鏡薄片以外，又包含雙 面凸透鏡或半球狀、砲彈狀等之種種形狀之薄片。作爲最 好的透鏡薄片，舉例有砲彈狀之稜鏡薄片或具有棱鏡角度 90度至100度之頂角的稜鏡薄片。 -11 - 200921204 光擴散薄片23、25 —般爲具備有於透明樹脂黏合劑 中含有光擴散劑之光擴散層之薄膜。本發明之光源裝置， 作爲上部用光擴散薄片25，係使用上述本發明之光擴散 薄膜。光擴散薄膜係配置成其凹凸面爲光射出側，亦即與 透鏡薄片24相反側上。又，亦有例如配置於導光板ρ反 射薄膜之未圖示之其他構件例如反射薄膜之情況。作爲下 部用光擴散薄片23’可使用一般的光擴散薄膜，較好爲 與1片至2片稜鏡薄片組合時亮度高且使導光板之圖型消 失者。 使用本發明之光擴散薄膜之上部用光擴散薄片25所 實現之光學特性，作爲一例，於Π S K 7 1 0 5 : 1 9 8 1中之霧 濁度爲30~50%，較好爲30〜40%;於JIS K7105: 1981中 之清晰度爲 2 0〜3 5 %，較好爲 2 5〜3 0 % ;於 JI S K 7 1 0 5 ·· 1981中之全光線透過率爲85 %以上。另一方面，下部用 光擴散薄片23之光學特性，於JIS K7105: 1981中之霧 濁度爲80~95%，較好爲85〜90%;於JIS K7105: 1981中 之清晰度爲 5-20%，較好爲 10%左右；於 JIS K7105: 1 9 8 1中之全光線透過率爲9 5 %以上。 藉由使用霧濁度高且清晰度低者作爲下部用光擴散薄 片23，可獲得高的亮度及光擴散性。又藉由使用保有較 低霧濁度且清晰度低者作爲上部用光擴散薄片25，可抑 制亮度的降低，且可抑制設置於其下方之透鏡薄片所引起 之眩眼同時不易見到透鏡薄片之透鏡圖型或傷痕等。 爲了獲得上述光學特性，下部用光擴散薄片之光擴散 -12- 200921204 層較好具有如下構成。作爲黏合劑樹脂，除了本發明之光 擴散薄膜中所說明之熱硬化型樹脂以外，可使用例如1分 子中具有2個以上丙烯醯基之藉由交聯硬化成爲3次元網 目構造之丙烯酸系預聚物等所構成之光聚合預聚物或單官 能丙烯酸單體或多官能丙烯酸單體等之電離輻射線硬化型 樹脂。氟系添加劑未必需要。又作爲光擴散劑亦可使用與 本發明之光擴散薄膜所使用者同樣的光擴散劑，但其添加 量相對於黏合劑樹脂100重量份爲50〜2 50重量份，較好 爲1 00-2 50重量份。 又作爲本發明光源裝置，於圖2雖說明使用導光板之 側光方式之背光裝置，但本發明之光源裝置亦可同樣地適 用於在擴散板下側配置光源，於上側依序配置下部用光擴 散薄片、透鏡薄片、上部用光擴散薄片之背光裝置。 [實施例] 以下說明本發明之實施例。以下實施例中，「份」、 「％」若無特別限制，則意指「重量份」、「重量％」。 [實施例1]200921204 IX. Description of the Invention [Technical Field] The present invention relates to a light diffusion thin film suitable for use in a light source curtain for a liquid crystal display, such as a light diffusion sheet or an anti-glare film, which can improve printing without impairing the original performance Suitability or processing of the film. [Prior Art] Optical films having light diffusibility are often used in liquid crystal displays and the like. For example, in a light source device of a liquid crystal display, a light-diffusing sheet for uniformizing light from a light source is realized on a light guide plate (light-emitting side) in which light from a source is converted into planar light. In many cases, a lens sheet for directing the light emitted from the light guide plate toward the front is disposed. In this case, a light diffusion sheet in which a pattern such as a mirror is not observed is disposed on the lens sheet. The light-diffusing sheet disposed on the lens sheet is different from the optical characteristics required for the arrangement of the light-diffusing sheet, and may be referred to as "upper" or "lower". Specifically, the light-diffusing sheet is required to increase the brightness of the film, and therefore has a high haze. On the other hand, the purpose of light diffusion for the upper portion is to suppress the glare of the lens or the concealment of the lens, so that (image sharpness) is low. A plurality of light-diffusing films which have been put into practical use, and have a light-diffusing layer having a light-diffusing agent such as a binder-dispersed pigment or a resin particle, and are used as a device and a fluorescent film, and in particular, a light diffuser or a fluorescent light is provided for guiding from the light. The light plate slabs and the like are used to make the ribs in the former of the light guide plate, and the lower part is made of the stencil and the slabs are used as the adhesive in the definition resin -4- 200921204 resin is thermosetting resin or ionizing radiation hardening type. Resin (Patent Document 1 and Patent Document 2). The ionizing radiation-curable resin is easier to adjust the balance of haze, sharpness, and brightness than the thermosetting resin. For example, when used in a light diffusing sheet of a liquid crystal display, it can easily satisfy the lower portion and the lower portion. Required characteristics for the upper part. [Patent Document 1] Japanese Laid-Open Patent Publication No. Hei. No. Hei. No. Hei. No. Hei. Use after cutting to an appropriate size. There are also cases where printing is applied to the surface depending on the purpose. For example, in the liquid crystal display, the upper light diffusing sheet is used, and in order to prevent leakage of light from the end portion of the liquid crystal display screen, a border printing is applied to the end portion of the light diffusing sheet. When the cutting or the printing is performed, the light-diffusing sheet obtained by using the ionizing radiation-curable resin as the binder resin has a problem that chipping is liable to occur at the time of cutting or the adhesion of the printing ink is deteriorated. Although the light-diffusing sheet obtained by using a thermosetting resin as the binder resin can reduce these problems, the balance of haze, sharpness, and brightness becomes difficult. In particular, in the case where the light-diffusing sheet is required to have a low definition and a high brightness, when the light diffusing agent is added to have an appropriate haze and brightness, the sharpness is too high, and the glare of the lens sheet cannot be suppressed. Conversely, if the definition is low, there is a problem that the brightness is also lowered. In order to solve the above problems, the present invention has an object of providing a light-diffusing film which is characterized by light diffusion and is excellent in adhesion to printing ink. [Means for Solving the Problem] In order to solve the above problems, the present inventors have made an improvement on the light diffusion layer using a thermosetting tree as a binder resin, and added it to the molecule in the light diffusion layer. When a fluorine-based additive containing a hydrophilic liquid or a paste is used, the desired brightness and sharpness can be obtained without impairing the printability or the cut-off property of the thermosetting resin, and in particular, the brightness can be improved and the clarity can be suppressed. Degrees, thus completing the present invention. That is, the light-diffusing film of the present invention is provided with a light-diffusing layer containing a binder tree and a light-diffusing agent, wherein the binder resin contains a heat-generating resin and a fluorine-based additive which does not contain a hydrophilic group in the molecule. . Further, the light-diffusing film of the present invention is characterized in that the fluorine-based additive molecule contains at least one fluoroalkyl group and at least one ether bond. Further, the light-diffusing film of the present invention is characterized in that the light-diffusing layer contains 20 parts by weight or more and 60 parts by weight or less of the light diffusing agent with respect to 100 parts by weight of the binder resin, and the haze of the light-diffusing film is 3 0% or more is less than 50%. In the light-diffusing film of the present invention, the fluorine-based additive is contained in an amount of 3 parts by weight or more and 100 parts by weight or less based on 100 parts by weight of the binder resin. The light source device of the present invention is characterized in that the photo-diffusion film is used in the presence of the above-mentioned light-diffusing film, and the fat is harder than the amount of the phase. -6 - 15 200921204, that is, the light source device of the present invention is provided with a light source and is disposed close to the light source. An optical plate that conducts light or diffuses light, a lens sheet disposed on a light-emitting side of the optical plate, and a light-diffusing sheet disposed on a side opposite to a light-emitting side of the lens sheet and/or a light-emitting side of the lens sheet. The above light diffusing sheet is characterized by the light diffusing film of the present invention. Further, the light source device of the present invention includes a light source, an optical plate disposed to be adjacent to the light source for guiding light or diffusing light, a lens sheet disposed on a light emitting side of the optical plate, and a light emitting side disposed on the light emitting surface of the lens sheet The first light-diffusing sheet on the opposite side and the second light-diffusing sheet disposed on the light-emitting side of the lens sheet are characterized in that the second light-diffusing sheet is the light-diffusing film of the present invention. Moreover, the light source device of the present invention is characterized in that the haze of the first light-diffusing sheet is 80 to 95%, the sharpness is 5 to 20%, and the haze of the second light-diffusing sheet is 30 to 50%. The resolution is 20 to 35%. [Embodiment] Hereinafter, embodiments of the light-diffusing film of the present invention will be described. First, the light diffusing film structure of the present invention is shown in Fig. 1. As shown in Fig. 1(a), the light-diffusing film 10 of the present invention may be composed of a single layer of the light-diffusing layer 11, or may be provided with light diffusion on the support 12 as shown in Fig. 1(b). Layer 1 is one. The support 12' is not particularly limited as long as it has high light transmittance and excellent transparency, and examples thereof include polyesters such as polyethylene terephthalate and polyethylene naphthalate. A resin; a cellulose resin such as a polyethylene terpene fiber 200921204 or a triacetyl cellulose; a polycarbonate resin; an acrylic resin such as polymethyl methacrylate. The side of the support 1 2 opposite to the side on which the light-diffusing layer is provided is preferably provided with a back coat layer 13 (Fig. 1 (c)) or the like for preventing curling of the light-diffusing film and improving scratch resistance. When the light-diffusing film of the present invention is used as a light-diffusing film on the upper portion of the backlight device, the light-diffusing layer 11 (surface having irregularities) is disposed on the light-emitting side, and the opposite side thereof is in contact with the lens sheet. By providing the scratch-resistant back coat 13 on the surface in contact with the lens sheet, it is possible to prevent the occurrence of scratches. As the material constituting the back coat layer 13, it is preferred to use the same resin as the binder resin of the light diffusion layer 1 1 to be described later. The thickness of the support 1 2 is not particularly limited, but when it is used as a light diffusion sheet for the upper portion of the backlight device, it is preferably 12 to 2 50 μm. Next, the light diffusion layer 1 1 of the light diffusion film will be described. The light diffusing layer is basically composed of a binder resin and a light diffusing agent. As the binder resin, a thermosetting resin is mainly used. By using a thermosetting resin, high hardness can be maintained, and when the resin is hardened by ionizing radiation, the occurrence of chips during processing at the time of machining is small, and the printability can be improved. Therefore, when the light-diffusing film of the present invention is used as a light diffusion sheet for the upper portion of the backlight device, the frame printing can be applied with good adhesion. As the thermosetting resin, urea resin, melamine resin, enamel resin, epoxy resin, unsaturated polyester resin 'alkyd resin, urethane carboxylic acid resin, acrylic resin, polyurethane, fluorine-based resin can be used. Known thermosetting resins such as resins, sand oxide resins, and polyimides, especially -8-200921204, are preferred for high transparency and hardness. Specifically, an acrylic resin obtained by reacting an acrylic polyol with an isocyanate or a polyester resin obtained by reacting a polyester polyol with an isocyanate is preferred. The hardness after hardening is preferably a pencil hardness of Η or more. The binder resin is at least 80% by weight or more, more preferably 90% by weight or more, of the above-mentioned thermosetting resin. In addition to the thermosetting resin, a thermoplastic resin such as an acrylic resin or a polyester resin may be contained in order to improve printability and cutoff properties. Further, the light-diffusing layer contains a fluorine-based additive which does not contain a hydrophilic group in the molecule, in addition to the binder resin. By using a thermosetting resin as the binder resin and adding a fluorine-based additive which does not contain a hydrophilic group in the molecule, similarly, in the case of using an ionizing radiation-curable resin, "undulation" occurs on the surface of the layer (not only It is a phenomenon in which the light diffusing agent protrudes from the surface and the layer of the adhesive resin is bulged around it, and effective light diffusibility can occur. Thereby, it is possible to obtain an effect of not lowering the brightness but suppressing the definition (image sharpness) to be low. By adding the fluorine-based additive to the binder resin containing the thermosetting resin as a main component, it is possible to obtain an optical property which is difficult to achieve only by the thermosetting resin, and a good haze and a low haze can be obtained. Sharpness and brightness. Further, by using the above "undulation", the amount of the light diffusing agent can be reduced. As the fluorine-based additive, an oligomer in which one or more fluoroalkyl groups are introduced into a molecule is used. Such an oligomer is in the form of a liquid or a paste before the addition. Further, it is used in a fluorine-based additive molecule which does not contain a sulfonic acid group or a hydrophilic group such as a carboxylic acid group -9-200921204. Fluorine-based additives containing a hydrophilic group in the molecule are difficult to reduce the definition. Therefore, when the light diffusing sheet is used as the upper portion, the sheet pattern which is disposed on the lower side can be recognized. Further, it is preferably one which is excellent in compatibility with the binder resin. By using a good compatibility with the binder resin, "undulation" can be effectively caused. When an acrylic resin or a polyester resin is used as the binder resin, an oligomer containing an ether bond is preferred. Specifically, a polyoxyethylene ether having a perfluoroalkyl group having a carbon number of C3 to C12 is preferred. The content of the fluorine-based additive varies depending on the amount of the light diffusing agent to be added, and if the amount of the light diffusing agent added is large, the content of the fluorine-based additive in a liquid or paste form is also required to increase. In one example, when the amount of the light diffusing agent added is 40 parts by weight or less based on 100 parts by weight of the binder resin, the fluorine-based additive is preferably 3 parts by weight or more and 1 part by weight based on 100 parts by weight of the binder resin. 5 parts by weight or less is more preferably 5 parts by weight or more and 1 part by weight or less. By setting the amount to be added in an amount of 3 parts by weight or more, the definition can be lowered, and the brightness can be kept within an appropriate range by being 15 parts by weight or less. As the light diffusing agent to be added to the light-diffusing layer, resin beads such as acrylic resin, polyurethane, polyvinyl chloride, polystyrene, polyamide or polycarbonate are used. Particularly preferred are acrylic resins and polystyrene. The average particle diameter of the resin beads is preferably from 1 to 20 μm, more preferably from 3 to 10 μm. When it is used as the upper light-diffusing sheet, the average particle diameter is ΙΟμm or less, and it is preferable that the particles having a maximum particle diameter of 3 〇μη or more are not contained. It is because the particles above 30 μm are recognized as foreign matter. The content of the resin beads in the light-diffusing layer varies depending on the use of the light-diffusing film. -10-200921204 is different, but when used as a light diffusion sheet for the upper portion, it is less than when used as a light diffusion sheet for the lower portion, and is less than the adhesive resin 1 00. The parts by weight are about 20 to 60 parts by weight, preferably 25 to 60 parts by weight. When a light-diffusing film such as an anti-glare film is used, it is about 5 to 15 parts by weight. In addition to the binder resin, the liquid or paste-like fluorine-based additive, and the resin beads which are mainly composed of the above-mentioned thermosetting resin, the light-diffusing layer may be added with an additive such as an ultraviolet absorber without hindering the properties. . The thickness of the light diffusion layer is not particularly limited, but is usually 5 to 15 μm. The light-diffusing film of the present invention can be obtained by applying a coating liquid prepared by adding a suitable solvent to a material constituting the light-diffusing layer, applying it to a support by a conventional coating method, and curing by heating. Alternatively, the material constituting the light diffusion layer may be processed into a film shape by extrusion molding or the like. Next, an embodiment of a light source device using the light-diffusing film of the present invention will be described. Fig. 2 is a view showing an example of a light source device using the light-diffusing film of the present invention. The light source device 20 shown in the drawing is an edge-light type backlight device, and includes a light source 21, a light guide plate 22, a light diffusion sheet 23 provided on the upper and lower portions thereof, and a light for the light guide plate 22. The lens sheet 24 facing the upper portion and the light diffusion sheet 25 provided on the upper portion of the lens sheet 24 are provided. The lens sheet is a sheet having various shapes such as a lenticular lens, a hemispherical shape, and a cannonball shape, in addition to a sheet having a specific apex angle, in addition to a sheet having a specific apex angle or a refractive characteristic. As the most preferable lens sheet, for example, a dome-shaped sheet or a sheet having a prism angle of 90 to 100 degrees. -11 - 200921204 The light-diffusing sheets 23 and 25 are generally films having a light-diffusing layer containing a light-diffusing agent in a transparent resin binder. In the light source device of the present invention, the light diffusing film of the present invention is used as the upper light diffusing sheet 25. The light-diffusing film is disposed such that its uneven surface is on the light-emitting side, that is, on the opposite side to the lens sheet 24. Further, for example, a member (not shown) disposed on the light guide plate ρ reflective film may be, for example, a reflective film. As the lower light-diffusing sheet 23', a general light-diffusing film can be used, and it is preferable that the brightness is high when combined with one to two sheets of the sheet, and the pattern of the light guide plate is lost. The optical characteristics achieved by using the light-diffusing sheet 25 on the upper portion of the light-diffusing film of the present invention are, as an example, a haze of 30 to 50%, preferably 30, in Π SK 7 1 0 5 : 1 9 8 1 . ~40%; in JIS K7105: 1981, the resolution is 2 0~3 5 %, preferably 2 5~3 0 %; in JI SK 7 1 0 5 ··1981, the total light transmittance is 85% the above. On the other hand, the optical characteristics of the lower light-diffusing sheet 23 have a haze of 80 to 95%, preferably 85 to 90% in JIS K7105: 1981, and a definition of 5 to 9 in JIS K7105: 1981. 20%, preferably about 10%; the total light transmittance in JIS K7105: 1 9 8 1 is 95% or more. By using the haze having a high haze and low definition as the lower light diffusion sheet 23, high luminance and light diffusibility can be obtained. Further, by using the light diffusing sheet 25 having a low haze and low definition, it is possible to suppress a decrease in brightness, and it is possible to suppress glare caused by a lens sheet disposed thereunder while not easily seeing the lens sheet. Lens pattern or scars, etc. In order to obtain the above optical characteristics, the light diffusion -12-200921204 layer of the lower light diffusion sheet preferably has the following constitution. In addition to the thermosetting resin described in the light-diffusing film of the present invention, for example, an acrylic resin having two or more acrylonitrile groups in one molecule and having a three-dimensional network structure by cross-linking and hardening can be used. A photopolymerizable prepolymer composed of a polymer or the like, or an ionizing radiation curable resin such as a monofunctional acrylic monomer or a polyfunctional acrylic monomer. Fluorine-based additives are not necessarily required. Further, as the light diffusing agent, the same light diffusing agent as that of the user of the light diffusing film of the present invention may be used, but the amount thereof is 50 to 2 50 parts by weight, preferably 100% by weight based on 100 parts by weight of the binder resin. 2 50 parts by weight. Further, as a light source device of the present invention, a backlight device using a side light type of a light guide plate will be described with reference to FIG. 2. However, the light source device of the present invention can be similarly applied to a light source disposed under the diffusion plate, and a lower portion is disposed on the upper side in order. A light diffusing sheet, a lens sheet, and a backlight device for a light diffusing sheet for the upper portion. [Examples] Hereinafter, examples of the invention will be described. In the following examples, "parts" and "%" mean "parts by weight" and "% by weight" unless otherwise specified. [Example 1]
於厚ΙΟΟμιη透明高分子薄膜（RUMILAR T60: TORAY 公司）之一表面上藉由桿塗佈法塗佈下述組成之光擴散用 塗佈液，經加熱硬化，形成厚度約1 Ομιη之光擴散層。 <光擴散層用塗佈液> -13- 200921204 •丙烯酸多元醇 32.4份 (ACRYDIC 49-394IM :大日本油墨化學工業公司） (固體成分5 0 %) •聚甲基丙烯酸甲酯真球狀粒子 8.0份 (TECHPOLYMER MBX-5 :積水化成品工業公司） •氟系添加劑 0.6份 (MEGAFUC F444，大日本油墨化學工業公司） •稀釋溶劑 6 1 · 3份 •硬化劑 6.3份 (TAKENATE D110N:三井化學聚胺酯公司） [實施例2] 除了實施例1之光擴散層用塗佈液中氟系添加劑量變 更爲3 · 0份以外，餘與實施例1同樣地形成光擴散層，獲 得光擴散薄膜。 [實施例3] 在與實施例1相同之透明高分子薄膜（RUMILAR Τ60 ·· TOR A Υ公司）之一表面上藉由桿塗佈法塗佈下述組 成之光擴散用塗佈液，經加熱硬化，形成厚度約1 〇 μ m之 光擴散層。 <光擴散層用塗佈液> -14- 200921204 •丙烯酸多元醇 32.4份 (ACRYDIC 49-3 94IM :大曰本油墨化學工業公司） (固體成分5 0 % ) •聚甲基丙烯酸甲酯真球狀粒子 8 · 0份 (TECHPOLYMER MBX-5 :積水化成品工業公司） •氟系添加劑 0.6份 (MEGAFACE F142D，大日本油墨化學工業公司） •稀釋溶劑 61.3份 •硬化劑 6 · 3份 (TAKENATED110N:三井化學聚胺基甲酸酯公司） [實施例4] 除了實施例3之光擴散層用塗佈液中氟系添加劑量變 更爲3 _ 0份以外，餘與實施例3同樣地形成光擴散層，獲 得光擴散薄膜。 [比較例1 ] 在與實施例1相同之透明高分子薄膜（RUMILAR T60 : TORAY公司）之一表面上藉由桿塗佈法塗佈下述組 成之光擴散用塗佈液，經加熱硬化’形成厚度約1 0 μιη之 光擴散層。 <光擴散層用塗佈液> -15- 200921204 丙烯酸多元醇 32.4份 (ACRYDIC 49-394IM ：大日本油墨化學工業公司） (固體成分5〇%) •聚甲基丙烯酸甲酯真球狀粒子 8.0份 (TECHPOLYMER MBX-5 :積水化成品工業公司） •稀釋溶劑 61.3份 硬化劑 6.3份 (TAKENATED110N:三井化學聚胺酯公司） [比較例2 ] 在與實施例1相同之透明高分子薄膜（RUMILAR T6 0 : TOR A Y公司）之一表面上藉由桿塗佈法塗佈下述組 成之光擴散用塗佈液，經加熱硬化，形成厚度約1 〇 μπι之 光擴散層。 <光擴散層用塗佈液> •丙烯酸多元醇 32.4份 (ACRYDIC 49-394ΙΜ:大日本油墨化學工業公司） (固體成分50%) •聚甲基丙烯酸甲酯真球狀粒子 8·〇份 (TECHPOLYMER MBX-5 :積水化成品工業公司） .氟系添加劑 0 · 6份 (MEGAFACEF477，大曰本油墨化學工業公司） •稀釋溶劑 6 1 . 3份 .硬化劑 6 · 3份 -16- 200921204 (ΤΑΚΕΝΑΤΕ D1 ION :三井化學聚胺酯公司） [比較例3 ] 在與實施例1相同之透明高分子薄膜（RUMILAR T60 : TORAY公司）之一表面上藉由桿塗佈法塗佈下述組 成之光擴散用塗佈液，經加熱乾燥，隨後藉由高壓水銀燈 照射紫外線而硬化，形成厚度約1 Ομιη之光擴散層。 <光擴散層用塗佈液> 電離輻射線硬化型丙烯酸樹脂 2 5.0份 (UNIDIC 17-813:大日本油墨化學工業公司） (固體成分80%) •聚甲基丙烯酸甲酯真球狀粒子 2.0份 (TECHPOLYMER ΜΒΧ-5 :積水化成品工業公司） .稀釋溶劑 75.0份 •光聚合起始劑 1 . 〇份 (IRGACURE 65 1： CIBA SPECIALTY CHEMICALS) 對實施例1〜4以及比較例1〜3所得之光擴散薄膜如下 述般評價霧濁度、全光線透過率、透過影像鮮明度（清晰 度）、加工適性（截斷適性）以及印刷適性。結果示於表1。 1.霧濁度及全光線透過率On the surface of one of the thick ΙΟΟμιη transparent polymer film (RUMILAR T60: TORAY), the coating liquid for light diffusion of the following composition was applied by a bar coating method, and heat-hardened to form a light diffusion layer having a thickness of about 1 μm . <Coating liquid for light-diffusing layer> -13- 200921204 •Acrylic polyol 32.4 parts (ACRYDIC 49-394IM: Dainippon Ink Chemical Industry Co., Ltd.) (solid content: 50%) • Polymethyl methacrylate ball 8.0 parts (TECHPOLYMER MBX-5: Sekisui Chemicals Co., Ltd.) • 0.6 parts of fluorine-based additive (MEGAFUC F444, Dainippon Ink Chemical Industry Co., Ltd.) • Diluting solvent 6 1 · 3 parts • Hardener 6.3 parts (TAKENATE D110N: Mitsui Chemical Polyurethane Co., Ltd. [Example 2] A light diffusion layer was formed in the same manner as in Example 1 except that the amount of the fluorine-based additive in the coating liquid for a light-diffusing layer of Example 1 was changed to 3.0 parts, and light diffusion was obtained. film. [Example 3] A coating liquid for light diffusion having the following composition was applied to the surface of one of the transparent polymer films (RUMILAR Τ 60 · TOR A Υ) which is the same as in Example 1 by a bar coating method. Heat hardened to form a light diffusion layer having a thickness of about 1 μm. <Coating liquid for light-diffusing layer> -14- 200921204 • 32.4 parts of acrylic polyol (ACRYDIC 49-3 94IM: Otsuka Ink Chemical Industry Co., Ltd.) (solid content 50%) • Polymethyl methacrylate True spherical particles 8 · 0 parts (TECHPOLYMER MBX-5: Sekisui Chemicals Co., Ltd.) • 0.6 parts of fluorine-based additive (MEGAFACE F142D, Dainippon Ink Chemical Industry Co., Ltd.) • 61.3 parts of dilution solvent • 6 · 3 parts of hardener ( TAKENATED 110N: Mitsui Chemical Polyurethane Co., Ltd. [Example 4] The same procedure as in Example 3 was carried out, except that the amount of the fluorine-based additive in the coating liquid for a light-diffusing layer of Example 3 was changed to 3 _ 0 parts. The light diffusion layer obtains a light diffusion film. [Comparative Example 1] A coating liquid for light diffusion having the following composition was applied to one surface of a transparent polymer film (RUMILAR T60: TORAY Co., Ltd.) similar to that of Example 1 by a bar coating method, and cured by heating. A light diffusion layer having a thickness of about 10 μm is formed. <Coating liquid for light-diffusing layer> -15- 200921204 32.4 parts of acrylic polyol (ACRYDIC 49-394IM: Dainippon Ink Chemical Industry Co., Ltd.) (solid content: 5〇%) • Polymethyl methacrylate true spherical 8.0 parts of particles (TECHPOLYMER MBX-5: Sekisui Chemicals Co., Ltd.) • Diluting solvent 61.3 parts of hardener 6.3 parts (TAKENATED 110N: Mitsui Chemical Polyurethane Co., Ltd.) [Comparative Example 2] The same transparent polymer film as in Example 1 (RUMILAR) On one of the surfaces of T6 0 : TOR AY, a light-diffusing coating liquid having the following composition was applied by a bar coating method, and cured by heating to form a light diffusion layer having a thickness of about 1 μm. <Coating liquid for light-diffusing layer> • 32.4 parts of acrylic polyol (ACRYDIC 49-394ΙΜ: Dainippon Ink Chemical Industry Co., Ltd.) (solid content: 50%) • Polymethyl methacrylate true spherical particles 8·〇 (TECHPOLYMER MBX-5: Sekisui Chemicals Industrial Co., Ltd.) Fluorine-based additive 0 · 6 parts (MEGAFACEF477, Otsuka Ink Chemical Industry Co., Ltd.) • Dilution solvent 6 1 . 3 parts. Hardener 6 · 3 parts - 16- 200921204 (ΤΑΚΕΝΑΤΕ D1 ION: Mitsui Chemical Polyurethane Co., Ltd.) [Comparative Example 3] The following composition was applied by a bar coating method on one surface of a transparent polymer film (RUMILAR T60: TORAY Co., Ltd.) similar to that of Example 1. The coating liquid for light diffusion is dried by heating, and then hardened by irradiation of ultraviolet rays with a high pressure mercury lamp to form a light diffusion layer having a thickness of about 1 μm. <Coating liquid for light-diffusing layer> Ionizing radiation-curable acrylic resin 2 5.0 parts (UNIDIC 17-813: Dainippon Ink Chemical Industry Co., Ltd.) (solid content 80%) • Polymethyl methacrylate true spherical 2.0 parts of granules (TECHPOLYMER ΜΒΧ-5: Sekisui Chemicals Co., Ltd.). Dilution solvent: 75.0 parts • Photopolymerization initiator 1. Ignition (IRGACURE 65 1: CIBA SPECIALTY CHEMICALS) For Examples 1 to 4 and Comparative Example 1 The obtained light-diffusing film was evaluated for haze, total light transmittance, transmission image sharpness (sharpness), processing suitability (cutting property), and printability as follows. The results are shown in Table 1. 1. Haze and total light transmittance
使用霧濁計（HGM-2K : SUGA試驗機公司）’依據 JIS K7 1 0 5 : 1 9 8 1，測定自光擴散薄片之擴散面入射光時之霧濁 度及全光線透過率。 -17- 200921204 2 ·透過影像鮮明度 使用影像測定器（ICM-1DP: SUGA試驗機公司），依 據JIS K7 1 05: 1 9 8 1，測定光學梳2.0mm之透過影像鮮明 度。 3 .加工適性 使光擴散薄膜1 00片重疊，由裁斷機加以裁斷’於裁 斷機刀刃部分未附著有切屑者記爲「〇」，附著有切屑者 記爲「X」。 4.印刷適性 於光擴散薄膜之光擴散層上，使用印刷用油墨 (SG7 00 : SEIKO先進公司），以絲網版網目#200印刷，藉 由棋盤格膠帶法（JIS-K5400)進行評價。由棋盤格膠帶法 之剝離試驗結果，棋盤格部分全部未剝離者記爲「〇」’ 棋盤格之一部分剝離者記爲「X」。 [表1]The haze and the total light transmittance at the time of incident light from the diffusing surface of the light-diffusing sheet were measured using a haze meter (HGM-2K: SUGA Testing Machine Co., Ltd.) in accordance with JIS K7 1 0 5 : 189. -17- 200921204 2 - Through the image sharpness Using an image measuring device (ICM-1DP: SUGA Testing Machine Co., Ltd.), according to JIS K7 05: 1 9 8 1, the optical brightness of the optical comb of 2.0 mm was measured. 3. Processing suitability The light-diffusing film was overlapped by 100 pieces and cut by a cutting machine. The person who has not attached the chip at the edge of the cutting machine is marked as "〇", and the person who has the chip attached is marked as "X". 4. Printability The printing ink (SG7 00: SEIKO Advanced Co., Ltd.) was used for printing on the light-diffusing layer of the light-diffusing film, and it was printed by the screen mesh #200, and evaluated by the checkerboard tape method (JIS-K5400). As a result of the peeling test by the checkerboard tape method, those who are not peeled off in the checkerboard portion are referred to as "〇". A part of the checkerboard is marked as "X". [Table 1]
氟系添加劑湘對黏合劑樹 脂100重量份之添加量） 霧濁度 (%) 全光線 透過率 清晰度 (%) 加工 適性 印刷 適性 實施例1 A(3重量份） 34.5 90.4 27.9 〇 〇 實施例2 A(15重量份） 34.9 90.4 27.7 〇 〇 實施例3 B(3重量份） 35.2 90.3 27.8 〇 〇 實施例4 B(15重量份） 35.7 90.3 27.7 〇 〇 比較例1 ίΒΕ 34.8 90.4 39.5 〇 〇 比較例2 C(15重量份） 35.4 90.3 40.1 〇 〇 比較例3 無勝樹脂 35.1 90.3 27.6 X X A :分子中含有醚鍵之液狀氟系添加劑（商品名： MEGAFACE F444 ’大日本油墨化學工業公司） 18- 200921204 B:分子中含有醚鍵之膏狀氟系添加劑（商品名： MEGAFACE F142D，大日本油墨化學工業公司） C :分子中不含有醚鍵之液狀氟系添加劑（商品名： MEGAFACEF477，大日本油墨化學工業公司） 如表1所示之結果所明確顯示，於黏合劑樹脂中含有 液狀或膏狀氟系添加劑之實施例1〜4之光擴散薄膜，滿足 上部用光擴散薄片所要求之光學特性，且截斷時不發生切 屑而加工性優異，且印刷適性亦優異。 另一方面，不含有氟系添加劑之比較例1及使用不含 醚鍵而含有親水性基者作爲氟系添加劑之比較例2之光擴 散薄膜，儘管使用與實施例同樣量之黏合劑樹脂以及光擴 散劑，但顯示其清晰度上升，作爲配置於稜鏡薄片之光射 側之上部用光擴散薄片之清晰度過大（看得到稜鏡薄片之 圖型）。又，使用UV樹脂替代熱硬化型樹脂作爲黏合劑 樹脂之比較例3之光擴散薄膜，發現到截斷時切屑發生， 且顯示印刷適性亦變差。 [實施例5]、[參考例1] 作爲參考例，測定市售之1 5型筆記型電腦中所用之 光源裝置（側光方式）之正面亮度。於此光源裝置，以自光 入射側朝光射出側依序組裝有下部用光擴散薄片（light UP LSE: KIMOTO公司）、2片稜鏡薄片（BEFII: 3M公司） 以及上部用光擴散薄片（LIGHT UP UK2 : KIMOTO公 -19- 200921204 司）。其上部用光擴散薄片係以含有黏合劑樹脂（丙烯酸系 預聚物）及光擴散劑（丙烯酸樹脂珠粒）且不含氟系添加劑 之光擴散層所形成者，霧濁度爲 29.5%，清晰度爲 28.5%。 以實施例1之光擴散薄膜替代上述光源裝置之上部用 光擴散薄片製作實施例5之光源裝置，與參考例同樣地測 定正面亮度。參考例之光源裝置，與本發明之光源裝置之 正面亮度比較，發現正面亮度同樣爲3 000cd/m2左右，爲 相同等級。 又，亦對稜鏡薄片之眩眼狀況進行觀察，參考例及實 施例5均無法辨識到稜鏡薄片之眩眼。由此結果，可確認 使用本發明之光擴散薄膜替代既有的上部用光擴散薄片構 成光源裝置，完全不損及光學性能。 [產業上之利用性] 依據本發明，提供一種不僅僅是光學特性優異，且加 工適性及印刷適性亦優異，尤其是適合作爲配置在光源裝 置之稜鏡薄片上之上部用光擴散薄片之光擴散薄膜。藉由 使用本發明之光擴散薄膜作爲光擴散薄片，可獲得不會因 該上部用光擴散薄片之插入而使亮度降低之光源裝置。 又，與稜鏡薄片配合加工或邊框印刷等之處理亦可順利進 行。 【圖式簡單說明】 -20- 200921204 圖1係顯示本發明之光擴散薄膜之實施形態圖。 圖2係顯示本發明之光源裝置之實施形態圖。 【主要元件符號說明】 I 〇 :光擴散薄膜 II :光擴散層 1 2 :支持體 1 3 :背塗層 20 :光源裝置 2 1 :光源 22 :導光板 23 ·’下部用光擴散薄片 24 :透鏡薄片 25 :上部用光擴散薄片 -21 -Fluoride additive added to 100 parts by weight of binder resin) Haze (%) Total light transmittance clarity (%) Processing suitability Printing Example 1 A (3 parts by weight) 34.5 90.4 27.9 Example 2 A (15 parts by weight) 34.9 90.4 27.7 〇〇 Example 3 B (3 parts by weight) 35.2 90.3 27.8 〇〇 Example 4 B (15 parts by weight) 35.7 90.3 27.7 〇〇Comparative Example 1 ίΒΕ 34.8 90.4 39.5 〇〇Comparative Example 2 C (15 parts by weight) 35.4 90.3 40.1 〇〇Comparative Example 3: Winner resin 35.1 90.3 27.6 XXA: Liquid fluorine-based additive containing an ether bond in a molecule (trade name: MEGAFACE F444 'Daily Ink Chemical Industry Co., Ltd.) 18 - 200921204 B: Paste-based fluorine-based additive containing an ether bond in the molecule (trade name: MEGAFACE F142D, Dainippon Ink Chemical Industry Co., Ltd.) C: Liquid fluorine-based additive containing no ether bond in the molecule (trade name: MEGAFACEF477, large Japanese Ink Chemical Industry Co., Ltd.) As shown by the results shown in Table 1, the light-diffusing film of Examples 1 to 4 containing a liquid or paste-like fluorine-based additive in the binder resin satisfies The optical properties required of the light diffusion sheet, does not occur and the workability is excellent swarf when cut, and, and also excellent in printability. On the other hand, in Comparative Example 1 which does not contain a fluorine-based additive, and the light-diffusing film of Comparative Example 2 which used a fluorine-based additive which does not contain an ether bond and which has a hydrophilic group, the same amount of adhesive resin and the same amount as the Example were used. The light-diffusing agent showed an increase in sharpness, and the sharpness of the light-diffusing sheet disposed on the upper side of the light-emitting side of the tantalum sheet was too large (a pattern of the tantalum sheet was observed). Further, in the light-diffusing film of Comparative Example 3 in which a UV resin was used instead of the thermosetting resin as the binder resin, it was found that chips were generated at the time of cutting, and the printability was also deteriorated. [Example 5], [Reference Example 1] As a reference example, the front luminance of a light source device (sidelight mode) used in a commercially available type 15 notebook computer was measured. In the light source device, a lower light diffusion sheet (light UP LSE: KIMOTO Co., Ltd.), two enamel sheets (BEFII: 3M company), and an upper light diffusion sheet are sequentially assembled from the light incident side toward the light exit side. LIGHT UP UK2 : KIMOTO -19-200921204 Division). The upper part of the light-diffusing sheet is formed of a light-diffusing layer containing a binder resin (acrylic prepolymer) and a light-diffusing agent (acrylic resin beads) and not containing a fluorine-containing additive, and has a haze of 29.5%. The resolution is 28.5%. The light source device of Example 5 was replaced with the light-diffusing film of Example 1 and the light-diffusing sheet of Example 5 was used, and the front luminance was measured in the same manner as in the reference example. In the light source device of the reference example, as compared with the front luminance of the light source device of the present invention, it was found that the front luminance was also about 3 000 cd/m 2 , which was the same level. Further, the glare condition of the enamel sheet was observed, and neither the reference example nor the example 5 could recognize the glare of the enamel sheet. As a result, it was confirmed that the light diffusing film of the present invention was used in place of the existing light diffusing sheet for the upper portion to constitute the light source device without impairing the optical properties. [Industrial Applicability] According to the present invention, it is possible to provide not only optical characteristics but also excellent workability and printability, and particularly suitable as light for diffusing a light-distributing sheet on a top sheet of a light source device. Diffusion film. By using the light-diffusing film of the present invention as a light-diffusing sheet, it is possible to obtain a light source device which does not reduce the brightness due to the insertion of the upper light-diffusing sheet. Further, the processing such as the processing of the enamel sheet or the border printing can be smoothly performed. BRIEF DESCRIPTION OF THE DRAWINGS -20- 200921204 Fig. 1 is a view showing an embodiment of a light-diffusing film of the present invention. Fig. 2 is a view showing an embodiment of a light source device of the present invention. [Description of main component symbols] I 〇: light diffusing film II: light diffusing layer 1 2 : support 1 3 : back coat layer 20 : light source device 2 1 : light source 22 : light guide plate 23 · 'lower light diffusing sheet 24 : Lens sheet 25: upper light diffusing sheet 21 -