201213977 六、發明說明: 【發明所屬之技術領域】 本發明係關於用於LCD之背光單元中的反射片,更具 體而言,係關於薄膜型背光單元之具有優異耐熱性的反射 片。 【先前技術】 反射片係作用來將自導光板下表面離開之光再次反射 向該導光板以最小化光之損失的膜。 近年來,隨著LED光源之採用,背光單元之厚度業經 得以減薄,且包括該反射片之光學膜也需要具有更薄之厚 度。然而,LED光源僅有20%之光效率且其能量約有80%作 為熱量而發射。結果,熱量保留於厚度較薄之背光中,導 致光學膜起皺。爲了解決這一問題,業經研發了一種多層 結構之反射片,其係藉由下列步驟而獲得:將黏合劑塗覆 於反射片之一個表面上,於其上沉積透明聚酯膜,以及於 其上形成可熱硬化的塗層。然而,這會由於黏合劑之塗覆 過程而在製造過程造成問題,及由於沉積兩個膜片而造成 成本增加。再者,由於熱量之長時間保留,不耐熱之黏合 劑層因受熱而產生畸變,造成出現彎曲或皺褶,導致影像 缺陷。再者,由於藉由層壓(lamination)來沉積片之結構, 該片之整體厚度係增加至300微米(#m)或更厚。 « 【發明内容】 技術問題 本發明之目的係提供不引起由於來自光源之熱所造成 4 95297 201213977 之彎曲或皺褶的反射片。具體而言,提供反射片,其具有 爲了改善耐熱性而使用uv塗覆組成物形成於該反射片兩 個表面上的塗層,同時具有200至280 之整體厚度。 本發明之另一目的係提供於一個表面上包括粒子(微 珠)之反射片,藉此防止磨損反射片與形成於導光板之下表 面上以使得光自該導光板離開之點印圖案或不均勻圖案 (藉由雷射處理)之間的界面,換言之,藉此防止因該反射 片之上表面與導光板之下表面彼此接觸而於兩者界面處產 生刮痕。 本發明之又一目的係提供藉由微凹版輥型 (microgravure roll type)塗覆方法形成之塗層,藉此使 用預設塗覆量形成均勻塗層。 [解決手段] 本發明係關於藉由使用UV-可固化的塗覆組成物於兩 個表面上形成塗層而具有優異财熱性的薄膜型反射片。特 別是,本發明之特徵在於將必需含有粒子之UV-可固化的 塗覆組成物塗覆於基膜之上表面。 於一通常態樣中,如第1圖所示,背光單元之反射片 係包括: 不透明聚酯膜作成之基膜; 藉由將第一 UV-可固化的塗覆組成物塗覆於該基膜之 上表面所形成之第一塗層,該第一塗層含有平均粒子尺寸 為3至50 ym之粒子;以及 藉由將第二UV-可固化的塗覆組成物塗覆於該基膜之 95297 201213977 下表面所形成之第二塗層,該第二塗層不含粒子, 其中,該反射片之整體厚度為200至280 /zm。 於另一通常態樣中,如第2圖所示,背光單元之反射 片係包括: 不透明聚酯膜作成之基膜; 藉由將第一 UV-可固化的塗覆組成物塗覆於該基膜之 上表面所形成之第一塗層,該第一塗層含有平均粒子尺寸 為3至50 # m之粒子;以及 藉由將第二UV-可固化的塗覆組成物塗覆於該基膜之 下表面所形成之第二塗層,該第二塗層含有平均粒子尺寸 為3至50 /z m之粒子;以及 其中,該反射片之整體厚度為200至280 # m。 於本發明中,該第一 UV-可固化的塗覆組成物與該第 二UV-可固化的塗覆組成物彼此可為相同或不同。 具體而言,於該第一塗層中使用之第一 UV-可固化的 塗覆組成物可含有:5至15重量(wt)%之藉由使聚碳酸酯 二醇與脂肪族二異氰酸酯化合物反應所獲得之胺甲酸乙酯 丙稀酸酯系寡聚物(urethane acrylate-based 〇1 igomer) ; 1至10 wt%之具有異氰脲酸酯基之丙稀酸酯單 體,5至10 wt%之羥基三曱基乙酸新戊基二醇二丙烯酸酯, 以及10至15 wt%之丙烯酸酯系單體混合物,該丙烯酸酯 系單體混合物為兩種或多種選自除了具有異氰脲酸酯基之 丙烯酸酯單體及羥基三曱基乙酸新戊基二醇二丙烯酸酯之 外的單丙烯酸酯系單體、雙官能丙烯酸酯系單體、三官能 6 95297 201213977 丙烯酸酯系單體及多官能丙烯酸酯系單體之丙烯酸酯系單 體混合物;1至5 wt%之光起始劑;5至15 wt%之平均粒子 尺寸為3至50 /zm之粒子;以及50至70 wt%之溶劑。 再者,於該第二塗層中使用之第二UV-可固化的塗覆 組成物可含有:5至15 wt%之藉由使聚碳酸酯二醇與脂肪 族二異氰酸酯化合物反應所獲得之胺甲酸乙酯丙烯酸酯系 寡聚物;1至10 wt%之具有異氰脲酸酯基之丙烯酸酯單體, 5至10 wt%之羥基三曱基乙酸新戊基二醇二丙烯酸酯,以 及10至15 wt%之丙烯酸酯系單體混合物,該丙烯酸酯系 單體混合物為兩種或更多種選自除了具有異氰脲酸酯基之 丙烯酸酯單體及羥基三甲基乙酸新戊基二醇二丙烯酸酯之 外的單丙烯酸酯系單體、雙官能丙烯酸酯系單體、三官能 丙烯酸酯系單體及多官能丙烯酸酯系單體之丙烯酸酯系單 體混合物;1至5 wt%之光起始劑;以及50至70 wt%之溶 劑。 再者,若需要,該第二UV-可固化的塗覆組成物可進 一步包括5至15 wt%之平均粒子尺寸為3至50# m之粒子。 根據本發明,塗層可形成於不透明聚酯基膜的兩個表 面上,藉此最小化由於熱造成之彎曲或皺褶,同時使得每 層塗層之整體厚度較薄。此處,爲了形成由於其對來自光 源之熱之優異耐性而無彎曲或皺褶的塗層,本研究證實最 佳係藉由使用UV-可固化的塗覆組成物形成該塗層。本案 發明人發現,當藉由將聚碳酸酯二醇與脂肪族二異氰酸酯 化合物反應所獲得之胺甲酸乙酯丙烯酸酯系寡聚物、具有 7 95297 201213977 異氰脲酸酯基之丙烯酸酯單體、羥基三曱基乙酸新戊基二 醇二丙烯酸酯、以及除了該具有異氰脲酸酯基之丙烯酸酯 單體及羥基三曱基乙酸新戊基二醇二丙烯酸酯之外的丙烯 酸酯系單體混合物作為該u v -可固化的塗覆組成物之成份 時,可提供具有優異耐熱性、優異耐磨性及高反射率之反 射片,從而完成本發明。 此外,本發明之特徵在於,以3至20/zm之厚度均勻 地塗覆該第一塗層及第二塗層。此處,若塗覆厚度少於3 ym,則樹脂之硬度由於空氣中氧之中斷而不足,且樹脂之 耐熱性質不足。若塗覆厚度大於20 ,則樹脂層可由於 其厚度厚而變得開裂或破損。 此外,爲了防止界面由於摩擦性研磨而磨損,該摩擦 性研磨係由於震動而出現於反射片之上部及導光板與層壓 之後提供於該導光板之下表面之點印圖案或藉由雷射處理 提供之不均勻圖案之間,形成於該塗層之上表面的第一塗 層係作成含有粒子,同時該等粒子之平均粒子尺寸為3至 50/zm,從而最小化藉由兩個彼此接觸之面之間的震動造成 的摩擦性研磨。此處,若該等粒子之平均粒子尺寸小於 3y m,則該等粒子係埋於該樹脂層中,從而最小化藉由表 面突起造成之表面接觸區域,導致滑脫性質不足。若該等 粒子之平均粒子尺寸大於50 # m,與該樹脂層之厚度相比, 則該等粒子太大,從而該等粒子與該塗層分離或由於過高 之表面不平性(unevenness)而損害該導光板之下表面。 【實施方式】 8 95297 201213977 後文將更詳細地揭示本發明之組成。 於本發明中,較佳係使用不透明度為95%或更高之不 透明聚酯膜作為基膜。較佳係使用玻璃轉化溫度為70至 80°C,較佳73至76°C之不透明聚酯膜,該聚酯膜保留耐 熱性質、耐濕性質及耐黃化性質以及於切割片時具有優異 之維度(dimensional)安定性,並由於界面處之折射率差異 而含有優異之光反射特徵,此係藉由大量微尺寸化之氣泡 所造成。下述兩種類型之膜都可用作該不透明聚酯膜:一 種將硫酸鋇或氧化鈦之無機粒子加入膜中之膜類型,以及 一種包括與聚酯膜合用之應用性差之有機粒子及藉由使得 界面由於成膜過程中之拉伸予以撕裂而形成之氣泡層的膜 類型。 於本發明中,該第一塗層係形成於基膜之上表面上且 層壓於導光板上。因此,爲了防止該第一塗層由於層壓於 導光板上而被磨損,係需要有粒子。至於該粒子,可使用 由硬丙烯酸酯、聚苯乙烯、尼龍、軟丙烯酸酯、矽酮等作 成之有機系聚合物珠。其中,較佳係對於由於震動而造成 之摩擦性研磨具有優異耐性的軟丙烯酸酯、尼龍、軟矽酮 等。該等粒子較佳係具有3至50 之平均粒子尺寸。若 該等粒子之平均粒子尺寸少於3# m,則該等粒子係埋於該 樹脂層中,從而最小化藉由表面突起造成之表面接觸面 積,導致滑脫性質不足。若該等粒子之平均粒子尺寸大於 50 " m,與該樹脂層之厚度相比,貝丨J該等粒子太大,從而該 等粒子與該塗層分離或由於過高之表面不平性而損害該導 9 95297 201213977 光板之下表面。基於用以形成該第一塗層之u 塗覆組成物的總重量,該專粒子含量 的 之範圍。若該等粒子之含量少…, 以至:無法提供表面之不平性,從而無法使得由於:: 板下表面之摩擦性研磨造成之刮痕的出現最小化。若該 粒子之含量大於15 wt%,由於uv樹脂之相對缺點,:機 械性質如表面粗糙度或耐熱性質之有效性極差。 於本發明巾,第-塗層之厚度⑽係意衫含粒子之 乾燥塗層厚度,如第丨_示。雜子储由使収寸大 於該塗覆厚度之粒子11而作成自該表面必要地突起。第一 塗層10之厚度(T2)較佳係3至20#m。若該塗覆厚度少於 3//m,則樹脂之硬度由於空氣中氧之中斷而不足,且樹脂 之而ί熱性質不足。右該塗覆厚度大於2 0 v m,則樹脂層可 月匕由於其厚度厚而開裂或破損。 於該第一 UV塗層中使用之第一 UV-可固化的塗覆組成 物可含有:5至15 wt%之藉由使聚碳酸酯二醇與脂肪族二 異氰酸酯化合物反應所獲得之胺甲酸乙酯丙烯酸醋系寡聚 物;1至10 wt%之具有異氰脲酸酯基之丙婦酸醋單體,5 至10 wt%之羥基三甲基乙酸新戊基二醇二丙烯酸醋,以及 10至15 wt°/。之丙烯酸酯系單體混合物,該丙缚酸醋系單體 混合物為兩種或更多種選自除了具有異氰脲酸g旨基之丙缔 酸酯單體及羥基三甲基乙酸新戊基二醇二丙烯酸酷之外的 單丙烯酸酯系單體、雙官能丙烯酸酯系單體、三官能丙稀 酸酿系單體及多官能丙稀酸醋系單體之丙稀酸I旨系單體混 95297 10 201213977 合物;1至5 Wt%之光起始劑;5至15 wt%之平均粒子尺寸 為3至50㈣之粒子;以及50至之溶劑尺寸 於,月中1¾第二塗層3〇係形成於基膜之下表面 二且:由塗覆如第一塗層中之具有耐熱性之樹脂而最小 ^於 料或皺褶的出現。於該塗層僅形成於該 土膜之上表面之例中’該樹脂由於熱而收縮,因此,該塗 層可能於樹脂塗覆之方向上出現彎曲。是故,於相對之 面上形成對稱之塗層’從而維持平衡。該第二塗層可含有 粒子31,如第2圖所示;或可不含粒子31,如第i圖所示。 於該第二塗層中使用之第二uv_可固化的塗覆組成物 可含有.5至15 wt%之藉由使聚碳酸酉旨二醇與脂肪族二異 氰酸酉旨化合物反應所獲得之胺曱酸乙醋丙稀酸酉旨系&聚 物,1至10 wt%之具有異氰腺酸酯基之丙烯酸酯單體,5 至10 wt%之縣三甲基乙酸新戊基二醇二丙烯酸酯,以及 10至15wt%之丙烯酸酯系單體混合物,該丙烯酸酯系單體 混合物為兩種或更多種選自除了具有異氰脲㈣基之丙婦 酸酯單體及羥基二甲基乙酸新戊基二醇二丙烯酸酯之外的 單丙烯酸酯系單體、雙官能丙烯酸酯系單體、三官能丙烯 酸酯系單體及多官能丙烯酸酯系單體之丙烯酸酯系單體混 合物;1至5 wt%之光起始劑;以及5〇至7〇 wt%2溶劑。 再者,如需要,該第二UV-可固化的塗覆組成物可進 一步包括5至15wt%之平均粒子尺寸為3至5〇//111之粒子。 該第二塗層30之厚度(T3)較佳係3至2〇//m。若該塗 覆厚度少於3ym,則樹脂之硬度由於空氣中氧之中斷而不 95297 11 201213977 足,且樹脂之耐熱性質不足。若該塗覆厚度大於20# m, 則樹脂層可能由於其厚度厚而開裂或破損。 於本發明中,可將對於光源造成之黃化係較少且具有 優異耐熱性及耐久性的組成物作為U V -可固化的塗覆組成 物使用於該第一塗層及第二塗層中,且其組合及含量範圍 可構成本發明之特徵。 於本發明中,該胺甲酸乙酯丙烯酸酯系寡聚物係藉由 使聚碳酸酯二醇與脂肪族二異氰酸酯化合物反應所獲得, 其具有優異之耐熱性,且其分子量較佳為1500至2000公 克(g)/莫耳(mol)。該聚碳酸酯二醇具有其中羥基係位於聚 碳酸酯結構之兩端的結構,且由柔軟觸感效果,聚碳酸酉旨 二醇之耐磨性及耐熱性優異。至於該脂肪族二異氰酸酯化 合物,可使用異佛酮二異氰酸酯、六亞甲基二異氰酸酯、 4, 4-二環己基曱烷二異氰酸酯等。其中,由於異佛酮二異 氰酸酯具有優異财熱性且黃化較少,其係較佳者。基於該 組成物之總重,該胺曱酸乙酯丙烯酸酯系寡聚物之含量較 佳係5至15 wt°/。。若該胺曱酸乙酯丙烯酸酯系寡聚物之含 量低於5 wt%,則表面硬度不足,因此,於硬化之後可能 仍保留黏性。若該胺曱酸乙酯丙烯酸酯系寡聚物之含量大 於15 wt%,則其本身之耐熱性質變得更佳但其剛性有下降 趨勢。 於本發明中,具有異氰脲酸酯基之丙烯酸酯單體係用 以改善耐熱性質及剛性,且該丙烯酸酯單體之具體實例可 為三(2-羥基乙基)異氰脲酸酯三丙烯酸酯(THEICTA)。該丙 12 95297 201213977 烯酸酯單體之含量較佳係1至10 wt%。 該經基三甲基乙酸新戊基二醇 善黏合性質,且其含量較佳係5至1G=酸酯婦係用以改 於本發明中,爲了滿足表面特徵,共° ,種選自H衫異級::基及_三曱基乙闕絲二 醇一丙稀酸醋之丙稀酸g旨單體之外 J早丙埽酸g旨丰單體、 雙官能丙浠酸醋系單體、三官能两稀酸i旨系單體及多官能 丙烯酸酯系單體之丙烯酸酯系單體混合物作為單體。 該丙烯酸酯系單體混合物係用以進一 π改吾UV可硬 化性。於本發明中,藉由使用兩種或更多㈣ 醋系單體、雙官能㈣義系單體、三官能輯酸醋系單 體及多官能丙烯酸酯系單體,可製備能促進黏度控制及塗 覆之形成均勻塗層的塗覆組成物。基於該組成物之總重 罝,該丙烯酸酯系單體混合物之含量較佳係至15 。 若其含量低於10 wt%,則黏度減薄效果劣化且可硬化性大 大地降低。若其含量大於15 wt%,包括耐熱性之耐久性大 大地降低。 至於該單丙烯酸酯系單體,可使用丙烯酸2_苯氧基乙 酯(2-phenoxy ethyl acrylate,2-PEA)、丙烯酸(2-(2- 乙氧基乙氧基)乙酯(Ε0Ε0ΕΑ)、丙烯醯氧基嗎啉(ACMO)等。 至於該雙官能丙烯酸酯系單體,可使用二丙二醇二丙 烯酸酯(DPGDA)、三丙二醇二丙烯酸酯(TPGDA)、丁二醇二 丙烯酸酯(BDDA)、雙酚A(乙氧基化物)二丙烯酸酯 (biphenol A(ethoxylate) dicarylate, BPA(EO)DA)、雙 13 95297 201213977 酚A(乙氧基化物)甲基二丙烯酸酯(BPA(E〇)4MDA).。 至於§亥二官能丙烯酸酯系單體,可使用三經甲基_ 三丙烯酸酯、季戊四醇三丙烯酸酯(ρΕΤΑ)、三曱基丙= 丙烯酸酯(ΤΜΡΤΑ)等。 土 '九三 至於該多官能丙烯酸酯單體,可使用二季戊四醇< 烯酸酯(DPHA)、二季戊四醇五丙烯酸酯⑺冲八)、季戊'、丙 四丙烯酸酯(ΡΕΤΤΑ)等。 四醇 於本發明中,爲了能夠UV硬化,必需含有光起 且任何能通常地祕UV硬化之光起㈣可不受=’ 作本發明之光起始劑。更佳係選自下列之一者或多 用 合物· 1-羥基-環己基-苯基-酮、2_苄基_2〜义^二見 基-1-(4-Ν-嗎啉基苯基)一卜丁酮、2一羥基_2一甲基—^―土胺 丙烷+酮、4, 4-二胺基二苯酮、2_曱基+ = 笨基]-2-Ν-嗎似丙n__、以及氧基_苯基_ ^土) 侧氧基-2-苯基-乙醯氧基一乙氧基)_乙基g旨與 2、 乙酸2普經基-乙氧基)_乙基醋(卜754, 本發明中之溶劑係用以控制黏度,從而改善粒子y ^ 分散性以及精確地將微米厚度之膜塗覆於气^膜之可 聚胺曱_丙馳聚Si 該丙烯酸U早體混合物之任何溶劑而無限制 = =甲基乙基酮、甲苯等,且可❹其混合物。該溶劑^ =較佳係50 i 7G wt%’且可製備於上揭範圍之_ J 有10至200厘泊(cps)(25t )之優異黏度的、 於本發明中,較佳係藉由使用預設之塗覆量均句地塗 95297 14 201213977 覆該第一塗層及第二層。塗覆方法之較佳實例可包括使用 微凹版輥之塗覆方法,但並不限於此。 於該第一塗層及第二塗層中使用之用於硬化該uv-可 固化的塗覆組成物之UV光的照射量為〇. 1至1焦耳(J)/ 平方公分(cm2) ’更佳為〇. 3至〇. 5 J/cm2。可使用以波長 為200至400奈米(nm)作為主要波長之高壓汞燈。 [有益效果] 本發明之反射片係具有小的整體厚度及優異耐熱性, 從而使得待製造之LCD之背光單元具有較小的整體厚度, 且本發明之反射片具有不平之上表面,從而防止其與導光 板之下表面之界面由於與該導光板之下表面之摩擦性研磨 而被磨損。 此外’本發明之反射片僅藉由使用塗覆處理而不需使 用層疊方法來製造,從而最小化製造成本。 結合後附之圖式,自上述較佳具體實施態樣之說明可 明瞭本發明之上述及其他目標、特徵及優點。 [最佳模式] 後文中,將藉由實施例詳細描述本發明,但本發明並 不限於下述實施例。 後文中’係藉由下述者測量物理學性質。 1) UV-可固化的塗覆組成物於硬化前之物理學性質 黏度·藉由使用布魯克菲爾德黏度計(Bro〇kfield VISCOMETER)(型號名:LVD-II+)於25°C測量樣本之黏度。 固體含量··將樣本於術°C供箱内保持】小時後取出, 95297 15 201213977 藉由下式1測量該樣本之固體含量。 [式1] 固體含量(%):[(容器+粗液體)_(容器)/樣本重量]x 100 2)具有塗層之反射片的物理學性質評估 黏合強度評估 將所製造之片切割為1〇〇個面積為1〇χ1〇毫米(mm) 之矩陣結構之後,將膠帶黏附於其上,隨後強力實施垂直 釋放(vertical releasing)。此時,記錄脫落之矩陣數目。 完成耐熱性評估後也於該樣本上實施上述黏合強度評估。 反射率測量 測量所製造之片的反射率。此處,藉由使用反射率測 量裝置(型號:Ultra Scan PRO)於550 nm測量反射率。 收縮測量 測量所製造之片的收縮。將經塗覆之反射片切割為具 有200 mm長度及15 mm寬度’隨後將其於15〇。(:烘箱中保 持3 0分鐘’並測量長度收縮變化。此處’分別測量該膜之 MD(膜之機械方向(mechanical direction))收縮及TD (膜 之橫向(traverse direction))收縮。 耐熱性評估 將多個反射片均勻地切割為A4尺寸,隨後將其分別於 90°C、100°C及120°C烘箱中保持1小時,測量該等反射片 之旋度及皺褶。 i)於每一溫度將反射片懸掛於每一烘箱之上端時,評 估每一反射片之彎曲狀態。 95297 16 201213977 ii)於每一溫度將反射片固定於玻璃板上表面之邊緣 時’評估每一反射片之彎曲狀態。 表面硬度 藉由使用錯筆硬度測試裝置(型號:KP-M5000M)於200g 負載測量反射片之鉛筆表面硬度。使用Mitsubishi公司生 產之鉛筆,將用於鉛筆表面硬度之測試實施五次。若擦痕 之數目為兩道或更多,則認為該反射片為有缺陷。 [製備例1至5] UV-可固化的塗覆組成物之製備 藉由以表1中所示之重量比組合各成份而製備可光硬 化之樹脂組成物。表1 (單位:wt%) 原料 製備例1 製備例2 製備例3 製備例4 製備例5 製備例6 製備例7 胺甲酸乙酯丙烯酸酯n 15 12 9 6 9 14 12 THEICTA2) 5 4. 5 3 3 4.5 8 4. 5 tpgda3) — — 一 6 _ dpgda4) 8. 5 6 9 6 _ 9 6 BPA(EO)4MDA5) — 一 一 一 7.5 _ HPNDAe) — 6 6 6 6 6 6 PETA7> — — 1.5 1.5 1. 5 1.5 曱笨 20 20 20 20 20 20 30 粒子8) 10 10 10 10 10 甲基乙基酮 40 40 40 40 40 40 40 光起始劑β) 1. 5 1. 5 1.5 1.5 1. 5 1.5 1. 5 1)胺甲酸乙酯丙烯酸酯:使用分子量為1800 g/m〇i之胺甲酸乙酯丙烯酸酯系寡聚 物,其係藉由將異佛酮二異氰酸酯與聚碳酸酯二醇以1:2之當量比反應所獲得。 17 95297 201213977 2) THEICTA:三(2-羥基乙基)異氱脲酸酯三丙烯酸酯 3) TPGDA:三丙二醇二丙烯酸酯 4) DPGDA:二丙二醇二丙烯酸酯 5) BPA(E0)4MDA :雙酚A乙氧基化物曱基二丙烯酸酯(乙氧基化物(E0),含量為4 mol%) 6) HPNDA :羥基三甲基乙酸新戊基二醇二丙烯酸酯 7) PETA:季戊四醇四丙烯酸酯 8) 粒子:使用平均粒子尺寸為15 之軟丙烯酸系樹脂珠(MX-1500, SokenBACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reflection sheet used in a backlight unit for an LCD, and more particularly to a reflection sheet having excellent heat resistance with respect to a film type backlight unit. [Prior Art] The reflection sheet acts to re-reflect the light exiting the lower surface of the light guide plate toward the light guide plate to minimize the loss of light. In recent years, with the adoption of LED light sources, the thickness of the backlight unit has been thinned, and the optical film including the reflective sheet also needs to have a thinner thickness. However, LED light sources emit only 20% of the light efficiency and about 80% of their energy is emitted as heat. As a result, heat is retained in the thinner backlight, causing the optical film to wrinkle. In order to solve this problem, a multilayered reflective sheet has been developed which is obtained by applying a binder to one surface of a reflective sheet, depositing a transparent polyester film thereon, and A heat hardenable coating is formed thereon. However, this causes problems in the manufacturing process due to the coating process of the adhesive, and an increase in cost due to the deposition of the two diaphragms. Moreover, due to the long-term retention of heat, the heat-resistant adhesive layer is distorted by heat, causing bending or wrinkles, resulting in image defects. Further, since the structure of the sheet is deposited by lamination, the overall thickness of the sheet is increased to 300 μm (#m) or more. « [Disclosure] [Technical Problem] An object of the present invention is to provide a reflection sheet which does not cause bending or wrinkles of 4 95297 201213977 due to heat from a light source. Specifically, a reflection sheet having a coating layer formed on both surfaces of the reflection sheet using a uv coating composition for improving heat resistance, and having an overall thickness of 200 to 280 is provided. Another object of the present invention is to provide a reflective sheet comprising particles (beads) on one surface, thereby preventing the worn reflective sheet from being printed on a lower surface of the light guide plate to cause light to exit from the light guide plate or The interface between the uneven patterns (by laser processing), in other words, thereby preventing the occurrence of scratches at the interface between the upper surface of the reflective sheet and the lower surface of the light guide plate in contact with each other. A further object of the present invention is to provide a coating formed by a microgravure roll type coating method whereby a uniform coating is formed using a predetermined coating amount. [Means for Solving] The present invention relates to a film-type reflection sheet having excellent heat recovery by forming a coating on both surfaces by using a UV-curable coating composition. In particular, the present invention is characterized in that a UV-curable coating composition which must contain particles is applied to the upper surface of the base film. In a general aspect, as shown in FIG. 1, the reflective sheet of the backlight unit comprises: a base film made of an opaque polyester film; by applying a first UV-curable coating composition to the base a first coating formed on a surface above the film, the first coating comprising particles having an average particle size of 3 to 50 μm; and coating the base film by applying a second UV-curable coating composition 95297 201213977 A second coating formed on the lower surface, the second coating is free of particles, wherein the reflective sheet has an overall thickness of 200 to 280 /zm. In another general aspect, as shown in FIG. 2, the reflective sheet of the backlight unit comprises: a base film made of an opaque polyester film; by applying a first UV-curable coating composition to the film a first coating formed on a surface above the base film, the first coating comprising particles having an average particle size of 3 to 50 #m; and coating the second UV-curable coating composition thereon a second coating formed on the lower surface of the base film, the second coating comprising particles having an average particle size of 3 to 50 /zm; and wherein the reflective sheet has an overall thickness of 200 to 280 #m. In the present invention, the first UV-curable coating composition and the second UV-curable coating composition may be the same or different from each other. Specifically, the first UV-curable coating composition used in the first coating layer may contain: 5 to 15% by weight of the polycarbonate diol and the aliphatic diisocyanate compound. Urethane acrylate-based oligoacrylate obtained by the reaction; 1 to 10 wt% of acrylate monomer having isocyanurate group, 5 to 10 a wt% of hydroxytrimercaptoacetic acid neopentyl glycol diacrylate, and 10 to 15% by weight of an acrylate monomer mixture, the acrylate monomer mixture being selected from two or more selected from the group consisting of isocyanuric acid Acrylate-based acrylate monomer and monoacrylate monomer other than hydroxytrimercaptoacetic acid neopentyl glycol diacrylate, difunctional acrylate monomer, trifunctional 6 95297 201213977 acrylate monomer And an acrylate monomer mixture of a polyfunctional acrylate monomer; 1 to 5 wt% of a photoinitiator; 5 to 15 wt% of an average particle size of 3 to 50 /zm; and 50 to 70 wt % solvent. Furthermore, the second UV-curable coating composition used in the second coating layer may contain: 5 to 15% by weight obtained by reacting a polycarbonate diol with an aliphatic diisocyanate compound. An urethane acrylate oligomer; 1 to 10 wt% of an acrylate monomer having an isocyanurate group, 5 to 10 wt% of hydroxytrimercaptoacetic acid neopentyl glycol diacrylate, And 10 to 15 wt% of an acrylate-based monomer mixture, the acrylate-based monomer mixture being two or more selected from the group consisting of acrylate monomers having an isocyanurate group and hydroxytrimethylacetate a monoacrylate monomer other than a pentyl glycol diacrylate, a difunctional acrylate monomer, a trifunctional acrylate monomer, and an acrylate monomer mixture of a polyfunctional acrylate monomer; 5 wt% of a photoinitiator; and 50 to 70 wt% of a solvent. Further, if desired, the second UV-curable coating composition may further comprise 5 to 15 wt% of particles having an average particle size of 3 to 50 #m. According to the present invention, the coating layer can be formed on both surfaces of the opaque polyester base film, thereby minimizing bending or wrinkles due to heat while making the overall thickness of each layer coating thin. Here, in order to form a coating which is not bent or wrinkled due to its excellent resistance to heat from a light source, the present study confirmed that it is preferable to form the coating by using a UV-curable coating composition. The inventors of the present invention have found that an urethane acrylate oligomer obtained by reacting a polycarbonate diol with an aliphatic diisocyanate compound, an acrylate monomer having an isocyanurate group of 7 95297 201213977 , hydroxytrimercaptoacetic acid neopentyl glycol diacrylate, and an acrylate system other than the isocyanurate group-containing acrylate monomer and hydroxytrimercaptoacetic acid neopentyl glycol diacrylate When the monomer mixture is used as a component of the uv-curable coating composition, a reflection sheet having excellent heat resistance, excellent abrasion resistance, and high reflectance can be provided, thereby completing the present invention. Further, the present invention is characterized in that the first coating layer and the second coating layer are uniformly applied in a thickness of 3 to 20 / zm. Here, if the coating thickness is less than 3 μm, the hardness of the resin is insufficient due to the interruption of oxygen in the air, and the heat resistance of the resin is insufficient. If the coating thickness is more than 20, the resin layer may be cracked or broken due to its thick thickness. In addition, in order to prevent the interface from being worn due to frictional grinding, the frictional grinding occurs on the upper portion of the reflective sheet due to vibration and the printing pattern provided on the lower surface of the light guide plate after the light guide plate and lamination or by laser Between the uneven patterns provided by the treatment, the first coating layer formed on the upper surface of the coating layer is made to contain particles, and the average particle size of the particles is 3 to 50/zm, thereby minimizing by means of two Friction grinding caused by vibration between the surfaces of the contacts. Here, if the average particle size of the particles is less than 3 μm, the particles are buried in the resin layer, thereby minimizing surface contact regions caused by surface protrusions, resulting in insufficient slip properties. If the average particle size of the particles is greater than 50 #m, the particles are too large compared to the thickness of the resin layer, such that the particles are separated from the coating or due to excessive surface unevenness. Damage to the lower surface of the light guide plate. [Embodiment] 8 95297 201213977 The composition of the present invention will be disclosed in more detail hereinafter. In the present invention, it is preferred to use an opaque polyester film having an opacity of 95% or more as a base film. It is preferred to use an opaque polyester film having a glass transition temperature of 70 to 80 ° C, preferably 73 to 76 ° C, which retains heat resistance, moisture resistance and yellowing resistance and is excellent in cutting sheets. Dimensional stability, and excellent light reflection characteristics due to the difference in refractive index at the interface, is caused by a large number of micro-sized bubbles. The following two types of films can be used as the opaque polyester film: a type of film in which inorganic particles of barium sulfate or titanium oxide are added to the film, and an organic particle including a poor application property in combination with the polyester film. A film type of a bubble layer formed by tearing the interface due to stretching during film formation. In the present invention, the first coating layer is formed on the upper surface of the base film and laminated on the light guide plate. Therefore, in order to prevent the first coating from being worn due to lamination on the light guide plate, particles are required. As the particles, organic polymer beads made of hard acrylate, polystyrene, nylon, soft acrylate, fluorenone or the like can be used. Among them, soft acrylate, nylon, soft ketone or the like which is excellent in frictional abrasion due to vibration is preferable. Preferably, the particles have an average particle size of from 3 to 50. If the average particle size of the particles is less than 3 #m, the particles are buried in the resin layer, thereby minimizing the surface contact area caused by the surface protrusions, resulting in insufficient slip properties. If the average particle size of the particles is greater than 50 " m, the particles are too large compared to the thickness of the resin layer, such that the particles are separated from the coating or due to excessive surface unevenness Damage to the lower surface of the guide plate 9 95297 201213977. The range of the specific particle content based on the total weight of the u coating composition used to form the first coating. If the content of the particles is small..., the surface unevenness cannot be provided, so that the occurrence of scratches due to:: frictional grinding of the lower surface of the plate cannot be minimized. If the content of the particles is more than 15% by weight, the mechanical properties such as surface roughness or heat resistance are extremely ineffective due to the relative disadvantages of the uv resin. In the towel of the present invention, the thickness (10) of the first coating layer is the thickness of the dried coating of the particles containing the particles, as shown in Figure _. The heteroleptic storage is made necessary to protrude from the surface by making the particles 11 larger than the coating thickness. The thickness (T2) of the first coating layer 10 is preferably from 3 to 20 #m. If the coating thickness is less than 3/m, the hardness of the resin is insufficient due to the interruption of oxygen in the air, and the resin is insufficient in heat. When the coating thickness on the right side is more than 20 v, the resin layer may be cracked or broken due to its thick thickness. The first UV-curable coating composition used in the first UV coating layer may contain: 5 to 15 wt% of a uric acid obtained by reacting a polycarbonate diol with an aliphatic diisocyanate compound. Ethyl acrylate vinegar oligomer; 1 to 10 wt% of acetoacetate monomer having isocyanurate group, 5 to 10 wt% of hydroxytrimethylacetic acid neopentyl glycol diacrylate vinegar, And 10 to 15 wt ° /. An acrylate-based monomer mixture having two or more selected from the group consisting of a propionate monomer having an isocyanuric acid group and a hydroxytrimethylacetate A monoacrylate monomer, a difunctional acrylate monomer, a trifunctional acrylic acid monomer, and a polyfunctional acrylic acid vine monomer Monomer 95297 10 201213977 compound; 1 to 5 Wt% photoinitiator; 5 to 15 wt% of particles having an average particle size of 3 to 50 (d); and 50 to solvent size in the middle of the first coating The layer 3 is formed on the lower surface 2 of the base film and is formed by coating the heat-resistant resin as in the first coating layer to minimize the occurrence of the material or wrinkles. In the case where the coating is formed only on the upper surface of the earth film, the resin shrinks due to heat, and therefore, the coating may be bent in the direction in which the resin is applied. Therefore, a symmetrical coating is formed on the opposite side to maintain balance. The second coating may contain particles 31 as shown in Figure 2; or may be free of particles 31, as shown in Figure i. The second uv_curable coating composition used in the second coating layer may contain from 5 to 15% by weight by reacting the polycarbonate diol with the aliphatic diisocyanate compound. Acetate acetoacetate acrylate & acrylate, 1 to 10 wt% of acrylate monomer having isocyanate group, 5 to 10 wt% of trimethylacetate a diol diacrylate, and 10 to 15% by weight of an acrylate monomer mixture, the acrylate monomer mixture being two or more selected from the group consisting of a propyl acrylate monomer having an isocyanuric acid (tetra) group And a monoacrylate monomer, a difunctional acrylate monomer, a trifunctional acrylate monomer, and an acrylate of a polyfunctional acrylate monomer other than hydroxydimethylammonioacetate diacrylate. a monomer mixture; 1 to 5 wt% of a photoinitiator; and 5 to 7 wt% of a solvent. Further, if desired, the second UV-curable coating composition may further comprise 5 to 15% by weight of particles having an average particle size of 3 to 5 Å//111. The thickness (T3) of the second coating layer 30 is preferably from 3 to 2 Å/m. If the coating thickness is less than 3 μm, the hardness of the resin is not sufficient due to the interruption of oxygen in the air, and the heat resistance of the resin is insufficient. If the coating thickness is more than 20 #m, the resin layer may be cracked or broken due to its thick thickness. In the present invention, a composition having less yellowing and having excellent heat resistance and durability against a light source can be used as the UV-curable coating composition in the first coating layer and the second coating layer. And combinations and ranges thereof may form features of the invention. In the present invention, the urethane acrylate-based oligomer is obtained by reacting a polycarbonate diol with an aliphatic diisocyanate compound, which has excellent heat resistance, and has a molecular weight of preferably 1,500 to 1,500. 2000 grams (g) / mol (mol). The polycarbonate diol has a structure in which the hydroxy group is located at both ends of the polycarbonate structure, and is excellent in abrasion resistance and heat resistance of the polycarbonate diol by a soft touch effect. As the aliphatic diisocyanate compound, isophorone diisocyanate, hexamethylene diisocyanate, 4, 4-dicyclohexyldecane diisocyanate or the like can be used. Among them, isophorone diisocyanate is preferred because it has excellent heat recovery and less yellowing. The amine phthalate acrylate oligomer is preferably contained in an amount of 5 to 15 wt% based on the total weight of the composition. . If the content of the amine phthalate acrylate oligomer is less than 5 wt%, the surface hardness is insufficient, and therefore, the viscosity may remain after hardening. If the content of the amine phthalate acrylate oligomer is more than 15% by weight, the heat resistance property itself becomes better but the rigidity tends to decrease. In the present invention, an acrylate monoester system having an isocyanurate group is used for improving heat resistance and rigidity, and a specific example of the acrylate monomer may be tris(2-hydroxyethyl)isocyanurate. Triacrylate (THEICTA). The content of the C12 95297 201213977 enoate monomer is preferably from 1 to 10% by weight. The mercaptotrimethylacetate neopentyl glycol has good adhesion properties, and its content is preferably 5 to 1 G=acid ester gynecological system for use in the present invention. In order to satisfy the surface characteristics, the species is selected from H. Equivalent to the shirt:: base and _ tridecyl acetonitrile diol acrylic acid acrylic acid acrylic acid g monomer other than J procylate g probiotic monomer, bifunctional propionate vinegar The monofunctional and trifunctional diacids are monomers as a monomer and a mixture of acrylate monomers of a polyfunctional acrylate monomer. The acrylate monomer mixture is used to further improve the UV hardenability. In the present invention, by using two or more (iv) vinegar monomers, difunctional (tetra) sense monomers, trifunctional acid vinegar monomers and multifunctional acrylate monomers, it is possible to prepare viscosity-promoting control. And a coating composition that forms a uniform coating. The content of the acrylate monomer mixture is preferably up to 15 based on the total weight of the composition. If the content is less than 10% by weight, the viscosity thinning effect is deteriorated and the hardenability is largely lowered. If the content is more than 15% by weight, the durability including heat resistance is largely lowered. As the monoacrylate monomer, 2-phenoxy ethyl acrylate (2-PEA) or 2-(2-ethoxyethoxy)ethyl acrylate (Ε0Ε0ΕΑ) can be used. , propylene methoxy morpholine (ACMO), etc. As the difunctional acrylate monomer, dipropylene glycol diacrylate (DPGDA), tripropylene glycol diacrylate (TPGDA), butanediol diacrylate (BDDA) can be used. ), bisphenol A (ethoxylate) dicarylate, BPA (EO) DA, double 13 95297 201213977 phenol A (ethoxylate) methyl diacrylate (BPA (E) 〇) 4MDA). As for the di-functional acrylate monomer, trimethyl-triacrylate, pentaerythritol triacrylate (ρΕΤΑ), tridecylpropane = acrylate (ΤΜΡΤΑ), etc. can be used. As for the polyfunctional acrylate monomer, dipentaerythritol < enoate (DPHA), dipentaerythritol pentaacrylate (7), pentaerythritol, propylene tetraacrylate, and the like can be used. Tetrahydrin In the present invention, in order to be able to be UV-cured, it is necessary to contain light and any light which can be normally cured by UV curing (4) can be used as the photoinitiator of the present invention. More preferably, it is selected from one or more of the following: 1-hydroxy-cyclohexyl-phenyl-ketone, 2-benzyl-2~-di-di-l-yl-1-(4-indole-morpholinylphenyl) ) acetophenone, 2-hydroxy-2-methyl-^-t-aminopropane + ketone, 4, 4-diaminobenzophenone, 2_mercapto + = stupid]-2-Ν- Propenyl n__, and oxy-phenylene_methane) side oxy-2-phenyl-ethoxycarbonyl-ethoxy)-ethyl g and 2, acetic acid 2 propyl-ethoxy) Ethyl vinegar (Bu 754, the solvent in the present invention is used to control the viscosity, thereby improving the dispersibility of the particles y ^ and precisely coating the film of the micron thickness on the gas film of the polyamine 曱 _ 驰 聚 poly Any solvent of the acrylic acid U early body mixture without limitation = = methyl ethyl ketone, toluene, etc., and may be a mixture thereof. The solvent ^ = preferably 50 i 7G wt% ' and can be prepared in the above range _ J has an excellent viscosity of 10 to 200 centipoise (cps) (25t). In the present invention, it is preferred to apply the first coating and the coating by using a predetermined coating amount of 95297 14 201213977. Two layers. A preferred example of the coating method may include a coating method using a micro gravure roll, but The irradiation amount of the UV light used for hardening the uv-curable coating composition used in the first coating layer and the second coating layer is 0.1 to 1 joule (J) / square centimeter. (cm2) 'More preferably 〇. 3 to 〇. 5 J/cm2. A high-pressure mercury lamp having a wavelength of 200 to 400 nanometers (nm) as a main wavelength can be used. [Advantageous Effects] The reflection sheet of the present invention has The small overall thickness and excellent heat resistance, so that the backlight unit of the LCD to be manufactured has a small overall thickness, and the reflective sheet of the present invention has an uneven upper surface, thereby preventing the interface with the lower surface of the light guide plate from being The lower surface of the light guide plate is abraded by frictional abrasion. Further, the reflective sheet of the present invention is manufactured only by using a coating process without using a lamination method, thereby minimizing the manufacturing cost. The above and other objects, features and advantages of the present invention will become apparent from the description of the preferred embodiments. Embodiments. The physical properties are measured by the following: 1) Physical properties of the UV-curable coating composition prior to hardening. By using a Brookfield viscometer (Bro〇kfield VISCOMETER) (Model name: LVD- II+) The viscosity of the sample was measured at 25 °C. Solid content····························································· [Formula 1] Solid content (%): [(container + crude liquid) _ (container) / sample weight] x 100 2) Physical properties of coated reflective sheet Evaluation of adhesive strength evaluation The cut piece was cut into After a matrix structure having an area of 1〇χ1〇mm (mm), the tape was adhered thereto, and then vertical releasing was strongly performed. At this time, the number of mating matrices is recorded. The above adhesion strength evaluation was also performed on the sample after the heat resistance evaluation was completed. Reflectance Measurement Measure the reflectivity of the manufactured sheet. Here, the reflectance was measured at 550 nm by using a reflectance measuring device (Model: Ultra Scan PRO). Shrinkage measurement Measure the shrinkage of the manufactured piece. The coated reflective sheet was cut to have a length of 200 mm and a width of 15 mm' followed by 15 〇. (: Hold in the oven for 30 minutes' and measure the change in length shrinkage. Here, 'the MD of the film (mechanical direction of the film) shrinkage and TD (traverse direction) shrinkage of the film were measured. Evaluation was performed by uniformly cutting a plurality of reflecting sheets into A4 size, and then holding them in an oven at 90 ° C, 100 ° C, and 120 ° C for 1 hour, respectively, and measuring the curl and wrinkles of the reflecting sheets. The bending state of each of the reflecting sheets was evaluated at each temperature when the reflecting sheets were suspended from the upper end of each of the ovens. 95297 16 201213977 ii) When the reflection sheet is fixed to the edge of the surface of the glass plate at each temperature, the bending state of each of the reflection sheets is evaluated. Surface Hardness The pencil surface hardness of the reflective sheet was measured by using a stray hardness tester (model: KP-M5000M) at a load of 200 g. The test for the surface hardness of the pencil was carried out five times using a pencil produced by Mitsubishi. If the number of scratches is two or more, the reflection sheet is considered to be defective. [Preparation Examples 1 to 5] Preparation of UV-curable coating composition A photohardenable resin composition was prepared by combining the components in the weight ratios shown in Table 1. Table 1 (unit: wt%) Raw material Preparation Example 1 Preparation Example 2 Preparation Example 3 Preparation Example 4 Preparation Example 5 Preparation Example 6 Preparation Example 7 Ethyl urethane acrylate n 15 12 9 6 9 14 12 THEICTA 2) 5 4. 5 3 3 4.5 8 4. 5 tpgda3) — — a 6 _ dpgda4) 8. 5 6 9 6 _ 9 6 BPA(EO)4MDA5) — 11 7.5 _ HPNDAe — — 6 6 6 6 6 6 PETA7> — — 1.5 1.5 1. 5 1.5 曱 20 20 20 20 20 20 30 30 particles 8) 10 10 10 10 10 methyl ethyl ketone 40 40 40 40 40 40 40 photoinitiator β) 1. 5 1. 5 1.5 1.5 1 5 1.5 1. 5 1) Ethyl acrylate acrylate: an urethane acrylate oligomer having a molecular weight of 1800 g/m〇i, which is obtained by using isophorone diisocyanate and polycarbonate The diol is obtained by reacting in an equivalent ratio of 1:2. 17 95297 201213977 2) THEICTA: Tris(2-hydroxyethyl)isophthalic acid triacrylate 3) TPGDA: tripropylene glycol diacrylate 4) DPGDA: dipropylene glycol diacrylate 5) BPA(E0)4MDA: double Phenol A ethoxylate decyl diacrylate (ethoxylate (E0), content 4 mol%) 6) HPNDA: hydroxytrimethyl acetic acid neopentyl glycol diacrylate 7) PETA: pentaerythritol tetraacrylate Ester 8) Particles: Soft acrylic beads with an average particle size of 15 (MX-1500, Soken)
Company) ° 9) 光起始劑:1-經基-環己基-苯基-酮(1-184, Ciba Company) 測量製備例1至7中製備之塗覆組成物的黏度及固體 含量,並將如是獲得之結果列述於表2中。 表2 製備例1 製備例2 製備例3 製備例4 製備例5 製備例6 製備例7 黏度(cps) 150 130 130 130 130 130 120 固體含量(90 30±2 30±2 30+2 30±2 30±2 30±2 30 + 2 [實施例1] 使用微凹版輥將製備例2中製備之UV-可固化的塗覆 組成物塗覆於基膜(SY70,225 # m PET膜,SKC Company) 之上表面上,使用微凹版輥將製備例6中製備之UV-可固 化的塗覆組成物塗覆於該基膜之下表面上。於維持 之塗覆厚度的同時實施該等塗覆。此處,該微凹版輥之孔 徑為55Φ,爲了均勻地增加塗覆厚度,使用50/50網目凹 版輥,運行速度及運行速度比係設置為最佳化條件。 18 95297 201213977 使用300 mJ/cm2之高壓汞燈測量塗覆之後的UV照射 量。測量因此獲得之反射片的物理性質,並將測量結果列 述於表3中。 [實施例2] 除了使用製備例3中製備之UV-可固化的塗覆組成物 作為待塗覆於該基膜之上表面的塗覆組成物之外,以與實 施例1相同之方法製造反射片。測量如是獲得之反射片的 物理性質,並將測量結果列述於表3中。 [實施例3] 除了使用製備例4中製備之UV-可固化的塗覆組成物 作為待塗覆於該基膜之上表面的塗覆組成物之外,以與實 施例1相同之方法製造反射片。測量如是獲得之反射片的 物理性質,並將測量結果列述於表3中。 [實施例4] 除了使用製備例5中製備之UV-可固化的塗覆組成物 作為待塗覆於該基膜之上表面的塗覆組成物之外,以與實 施例1相同之方法製造反射片。測量如是獲得之反射片的 物理性質,並將測量結果列述於表3中。 [實施例5] 使用微凹版輥將製備例2中製備之UV-可固化的塗覆 組成物塗覆於基膜(SY70,225 #m PE:T膜,SKC Company) 之上表面上,使用微凹版輥將製備例3中製備之UV-可固 化的塗覆組成物塗覆於該基膜之下表面上。於維持10/zm 之塗覆厚度的同時實施塗覆。此處,該微凹版輥之孔徑為 19 95297 201213977 55Φ ’爲了均句地增加塗覆厚度,使用5〇/5〇網目凹版親, 運行速度及運行速度比係設置為最佳化條件。 使用300 mJ/cm2之高壓采燈測量塗覆之後的uv照射 量。測量如是獲得之反射片的物理性質,並將測量結果列 述於表3中。 [實施例6] 使用微凹版輥將製· 7 +製備之uv_可固化的塗覆 組成物塗覆於基膜(SY70,225 em pet膜,SKC c〇mpany) 之上表面上,使用微凹版輥將製備例7中製備之可固 化的塗覆組成物塗覆於該基膜之下表面上。於維持1〇 _ 之塗覆厚度的同時實施塗覆。此處,該微凹版輥之孔 55Φ,爲了均勻地增加塗覆厚度,使用5(),網目凹版親, 運行速度及運行速度比係設置為最佳化條件。 使用300 mJ/cra2之高壓汞燈測量塗覆之後的-照射 量。測量如是獲得之反射片的物理性f,並將測量結果列 述於表3中。 [比較例1] 測量兩個表面都不塗覆實施例丨中之塗層之基) (SY70, 225 Am PET 膜,SKC c〇mpany)的^二Company) ° 9) Photoinitiator: 1-carbyl-cyclohexyl-phenyl-ketone (1-184, Ciba Company) The viscosity and solid content of the coating compositions prepared in Preparations 1 to 7 were measured, and The results obtained as described are listed in Table 2. Table 2 Preparation Example 1 Preparation Example 2 Preparation Example 3 Preparation Example 4 Preparation Example 5 Preparation Example 6 Preparation Example 7 Viscosity (cps) 150 130 130 130 130 130 120 Solid content (90 30 ± 2 30 ± 2 30 + 2 30 ± 2 30±2 30±2 30 + 2 [Example 1] The UV-curable coating composition prepared in Preparation Example 2 was applied to a base film using a micro gravure roll (SY70, 225 # m PET film, SKC Company On the upper surface, the UV-curable coating composition prepared in Preparation Example 6 was applied onto the lower surface of the base film using a micro gravure roll. The coating was carried out while maintaining the coating thickness. Here, the micro gravure roll has a hole diameter of 55 Φ, and in order to uniformly increase the coating thickness, a 50/50 mesh gravure roll is used, and the running speed and the running speed ratio are set as optimum conditions. 18 95297 201213977 Using 300 mJ/ The high-pressure mercury lamp of cm2 was used to measure the amount of UV irradiation after coating. The physical properties of the thus obtained reflection sheet were measured, and the measurement results are shown in Table 3. [Example 2] Except that UV-prepared in Preparation Example 3 was used. The curable coating composition is outside the coating composition to be applied to the upper surface of the base film, A reflective sheet was produced in the same manner as in Example 1. The physical properties of the obtained reflective sheet were measured, and the measurement results are shown in Table 3. [Example 3] In addition to the UV-curable preparation prepared in Preparation Example 4 The coating composition was used as a coating composition to be applied to the upper surface of the base film, and a reflecting sheet was produced in the same manner as in Example 1. The physical properties of the obtained reflecting sheet were measured, and the measurement results were listed. It is described in Table 3. [Example 4] In addition to using the UV-curable coating composition prepared in Preparation Example 5 as a coating composition to be applied to the upper surface of the base film, A reflecting sheet was produced in the same manner as in Example 1. The physical properties of the obtained reflecting sheet were measured, and the measurement results are shown in Table 3. [Example 5] The UV-curable prepared in Preparation Example 2 was prepared using a micro gravure roll. The coating composition was applied to the upper surface of a base film (SY70, 225 #m PE: T film, SKC Company), and the UV-curable coating composition prepared in Preparation Example 3 was coated using a micro gravure roll. Overlying the lower surface of the base film to maintain a coating thickness of 10/zm At the same time, the coating is applied. Here, the aperture of the micro gravure roll is 19 95297 201213977 55Φ 'In order to increase the coating thickness uniformly, the 5 〇 5 〇 mesh intaglio is used, and the running speed and the running speed ratio are set to the maximum. The uv exposure amount after coating was measured using a high pressure lamp of 300 mJ/cm2. The physical properties of the obtained reflection sheet were measured, and the measurement results are listed in Table 3. [Example 6] Using micro The gravure roll was applied to the upper surface of the base film (SY70, 225 em pet film, SKC c〇mpany) by a 7+ prepared uv_curable coating composition, and the preparation example 7 was used using a micro gravure roll. The prepared curable coating composition is applied to the lower surface of the base film. Coating was carried out while maintaining a coating thickness of 1 Å. Here, the hole 55Φ of the micro gravure roll, in order to uniformly increase the coating thickness, is set to an optimum condition using 5 (), gravure, running speed and running speed ratio. The amount of irradiation after coating was measured using a high pressure mercury lamp of 300 mJ/cra2. The physical properties f of the obtained reflection sheet were measured, and the measurement results are shown in Table 3. [Comparative Example 1] The measurement was carried out on both surfaces of the coating in which neither of the coatings in Example ) was applied (SY70, 225 Am PET film, SKC c〇mpany)
結果係列述於表3中。 丨賀、JThe results series are described in Table 3. Hehe, J
[比較例2] 、彳量可商購之層壓反射片RL713K產品(SKC-Ha£ Company)之物理性質,測量結果係列述於表3中。該㈣〔 '、"有如下結構·其中,聚酯系黏合劑層係形成於』 95297 20 201213977 膜(SY70,225μπι不透明聚對苯二曱酸伸乙酯膜,SKC Company)上,其上沉積有100 μ m之透明對苯二曱酸伸乙酯 膜(V5200,SKC Company),且其上形成有硬塗層。 [比較例3] 除了使用製備例1中製備之UV-可固化的塗覆組成物 作為待塗覆於該基膜之上表面的塗覆組成物之外,以與實 施例1相同之方法製造反射片。測量如是獲得之反射片的 物理性質’並將測量結果列述於表3中。 表3[Comparative Example 2] The physical properties of a commercially available laminated reflective sheet RL713K product (SKC-Ha£ Company), and the series of measurement results are shown in Table 3. The (4) [ ', " has the following structure: wherein the polyester adhesive layer is formed on the film (SY70, 225μπι opaque polyethylene terephthalate ethyl ester film, SKC Company), on which A 100 μm transparent terephthalate film (V5200, SKC Company) was deposited and a hard coat layer was formed thereon. [Comparative Example 3] The same procedure as in Example 1 was carried out except that the UV-curable coating composition prepared in Preparation Example 1 was used as a coating composition to be applied to the upper surface of the base film. A reflective sheet. The physical properties of the obtained reflection sheet were measured' and the measurement results are shown in Table 3. table 3
實施例1 實施例2 實施例3 實施例4 實施例5 實施例6 比較例1 比較例2 比較例3 黏度(cps) 130 130 130 130 130 130 _ _ 130 固體含量U) 30 + 2 30+2 30+2 30+2 30+2 30±2 _ _ 30±2 黏合強度 100/100 100/100 100/100 100/100 100/100 100/100 _ 100/100 反射率 (% 550 nm ) 96. 15 96. 5 96. 4 96. 4 96. 5 96. 5 97 95. 6 96.3 收縮 m)% 0. 003 0. 004 0. 004 0. 004 0. 0025 0.0025 0. 02 0. 005 0. 01 收縮 (TD)% 0. 0025 0. 003 0. 0035 0.0035 0. 0025 0.0025 0. 005 0. 01 0. 005 耐熱性 評估 loot 1mm 1· 5_ 1. 5mm 1.5mm hm 1mm 2mm 5cm t 6mm 耐熱性 評估 120°C 1mm 1. 5qhq 1. 5mm 1. 5mni 1mm llUID 3miD 8cm f 6mm 表面硬度 HB’F H HB-F HB H H 一 — HB 從表3可知’以反射率觀點來看,實施例1至6係盥 比較例1相似,以收縮觀點來看,實補】至6係優於比 較例2 ’且實施例1至6亦於耐熱性評估時顯現良好之彎 曲狀態並於硬化賴現良好之表面硬度。對應於其中不含 95297 21 201213977 有羥基三曱基乙酸新戊基二丙烯酸酯之例的比較例3則顯 示劣化之财熱性。 【圖式簡單說明】 第1圖係根據本發明之較佳具體實施例之反射片的橫 截面圖;以及 第2圖係根據本發明之另一較佳具體實施例之反射片 的橫截面圖。 【主要元件符號說明】 10 第一塗層 11、31 粒子 20 基膜 30 第二塗層 T1 整體厚度 T2 第一塗層之厚度 T3 第二塗層之厚度 22 95297Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Comparative Example 1 Comparative Example 2 Comparative Example 3 Viscosity (cps) 130 130 130 130 130 130 _ _ 130 Solid content U) 30 + 2 30+2 30+2 30+2 30+2 30±2 _ _ 30±2 Adhesive strength 100/100 100/100 100/100 100/100 100/100 100/100 _ 100/100 Reflectance (% 550 nm) 96. 15 96. 5 96. 4 96. 4 96. 5 96. 5 97 95. 6 96.3 Shrinkage m)% 0. 003 0. 004 0. 004 0. 004 0. 0025 0.0025 0. 02 0. 005 0. 01 Shrinkage (TD)% 0. 0025 0. 003 0. 0035 0.0035 0. 0025 0.0025 0. 005 0. 01 0. 005 Heat resistance evaluation loot 1mm 1· 5_ 1. 5mm 1.5mm hm 1mm 2mm 5cm t 6mm Heat resistance evaluation 120°C 1mm 1. 5qhq 1. 5mm 1. 5mni 1mm llUID 3miD 8cm f 6mm Surface hardness HB'F H HB-F HB HH 1- HB As can be seen from Table 3, from the viewpoint of reflectivity, Examples 1 to 6 The system is similar to Comparative Example 1, and from the viewpoint of shrinkage, the actual complement to the 6-series is superior to the comparative example 2' and the examples 1 to 6 also exhibit a good bending state at the time of heat resistance evaluation and a surface which is hardened by hardening. hardness. Comparative Example 3 corresponding to the example in which no 95297 21 201213977 hydroxytrimercaptoacetic acid neopentyl diacrylate was contained showed the deterioration of the heat. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a cross-sectional view of a reflective sheet in accordance with a preferred embodiment of the present invention; and Figure 2 is a cross-sectional view of a reflective sheet in accordance with another preferred embodiment of the present invention. . [Main component symbol description] 10 First coating 11, 31 particles 20 Base film 30 Second coating T1 Overall thickness T2 Thickness of first coating T3 Thickness of second coating 22 95297