本發明中，當一個部分「包括」一個要素時，除非另有描述，否則亦可包括另一要素，而不排除該另一要素之存在。 在下文中，將參考示例性實施方式詳細描述本發明。＜ 硬質塗佈組合物 ＞
根據本發明之一個示例性之實施方式的硬質塗佈組合物包括彈性模數為10 MPa至3000 MPa且斷裂伸長率為30%至150%之高伸長率低聚物。當硬質塗佈組合物具有在此等範圍內之彈性模數及斷裂伸長率時，可表現出優異之抗彎曲性及抗衝擊性。高伸長率低聚物
根據本發明之硬質塗佈組合物包括高伸長率低聚物。 高伸長率低聚物包括可光固化(甲基)丙烯酸酯低聚物。 可光固化(甲基)丙烯酸酯低聚物可包括選自由環氧(甲基)丙烯酸酯、胺基甲酸酯(甲基)丙烯酸酯及聚酯(甲基)丙烯酸酯組成之群中之一或多者。 環氧(甲基)丙烯酸酯可藉由使具有(甲基)丙烯醯基之羧酸與環氧化合物反應而獲得。具體地，環氧化合物可係(甲基)丙烯酸縮水甘油酯、C1
至C12
直鏈醇封端之縮水甘油醚、二甘醇二縮水甘油醚、三丙二醇二縮水甘油醚、雙酚A二縮水甘油醚、環氧乙烷改性之雙酚A二縮水甘油醚、環氧丙烷改性之雙酚A二縮水甘油醚、三羥甲基丙烷三縮水甘油醚、季戊四醇四縮水甘油醚、氫化雙酚A二縮水甘油醚、丙三醇二縮水甘油醚等。具有(甲基)丙烯醯基之羧酸可係(甲基)丙烯酸、2-(甲基)丙烯醯氧基乙基琥珀酸、2-(甲基)丙烯醯氧基乙基六氫鄰苯二甲酸等。 胺基甲酸酯(甲基)丙烯酸酯可藉由在催化劑之存在下使分子中具有羥基之多官能(甲基)丙烯酸酯及具有異氰酸酯基之化合物反應來製備。 分子中具有羥基之(甲基)丙烯酸酯可係選自由(甲基)丙烯酸2-羥基乙酯、(甲基)丙烯酸2-羥基異丙酯、(甲基)丙烯酸-4-羥基丁酯、己內酯開環之羥基丙烯酸酯，季戊四醇三(甲基)丙烯酸酯與季戊四醇四-(甲基)丙烯酸酯之混合物、以及二季戊四醇五-(甲基)丙烯酸酯與二季戊四醇六-(甲基)丙烯酸酯之混合物組成之群中的一或多者。 分子中具有異氰酸酯基之化合物可係選自由以下組成之群中之一或多者：1,4-二異氰酸基丁烷、1,6-二異氰酸基己烷、1,8-二異氰酸基辛烷、1,12-二異氰酸基十二烷、1,5-二異氰酸基-2-甲基戊烷、三甲基-1,6-二異氰酸基己烷、1,3-雙(異氰酸酯基甲基)環己烷、反式-1,4-環己烷二異氰酸酯、4,4'-亞甲基雙(環己基異氰酸酯)、異佛爾酮二異氰酸酯、甲苯-2,4-二異氰酸酯、甲苯-2,6-二異氰酸酯、二甲苯-1,4-二異氰酸酯、四甲基二甲苯-1,3-二異氰酸酯、1-氯甲基-2,4-二異氰酸酯、4,4'-亞甲基雙(2,6-二甲基苯基異氰酸酯)、4,4'-氧基雙(苯基異氰酸酯)、來自六亞甲基二異氰酸酯之三官能異氰酸酯及三甲基丙醇-甲苯二異氰酸酯加合物。 聚酯(甲基)丙烯酸酯，具體地，可係二丙烯酸酯(例如乙二醇二(甲基)丙烯酸酯、二甘醇二(甲基)丙烯酸酯、三甘醇二(甲基)丙烯酸酯、聚乙二醇二(甲基)丙烯酸酯、丙二醇二(甲基)丙烯酸酯、二丙二醇二(甲基)丙烯酸酯、三丙二醇二(甲基)丙烯酸酯、1,4-丁二醇二(甲基)丙烯酸酯、新戊二醇二(甲基)丙烯酸酯、1,6-己二醇二(甲基)丙烯酸酯、三環癸烷二(甲基)丙烯酸酯、雙酚A二(甲基)丙烯酸酯等)、三羥甲基丙烷三(甲基)丙烯酸酯、季戊四醇三(甲基)丙烯酸酯、季戊四醇四(甲基)丙烯酸酯、雙三羥甲基丙烷四(甲基)丙烯酸酯、二季戊四醇五(甲基)丙烯酸酯、二季戊四醇六(甲基)丙烯酸酯、三(2-(甲基)丙烯醯氧基乙基)異氰脲酸酯等。 較佳組合使用胺基甲酸酯(甲基)丙烯酸酯及聚酯(甲基)丙烯酸酯，或者在一個分子中包括聚酯基團及胺基甲酸酯基團兩者。 特別地，具有線性結構之丙烯酸酯低聚物可用於形成具有30%或更大之伸長率之硬質塗膜。較佳地，使用具有線性結構及顯示出優異之可撓性之聚酯(甲基)丙烯酸酯。 相對於100重量%之全部硬質塗佈組合物，該硬質塗佈組合物可較佳地包括1重量%至90重量%，更佳地5重量%至80重量%之高伸長率低聚物。當高伸長率低聚物之含量小於1重量%時，難以形成塗膜，或者即使形成塗膜，亦難以製造具有足夠之抗衝擊性水準之硬質塗佈組合物。另一方面，當高伸長率低聚物之含量大於90重量%時，由於使用硬質塗佈組合物製造硬質塗膜期間之高黏度，塗膜之均勻性會降低。 在本發明之一個示例性實施方式中，硬質塗佈組合物亦可包括選自由溶劑、光引發劑及添加劑組成之群中之一或多者。溶劑
溶劑係可溶解或分散上述組合物之材料，且可使用而沒有限制，只要其係此項技術中已知之硬質塗佈組合物之溶劑。 具體地，溶劑可較佳為醇(例如甲醇、乙醇、異丙醇、丁醇、甲基溶纖劑、乙基溶纖劑等)，酮(例如甲基乙基酮、甲基丁基酮、甲基異丁基酮、二乙基酮、二丙基酮、環己酮等)，乙酸酯(例如乙酸乙酯、乙酸丙酯、乙酸正丁酯、乙酸第三丁酯、甲基溶纖劑乙酸酯、乙基溶纖劑乙酸酯、丙二醇單甲醚乙酸酯、丙二醇單乙醚乙酸酯、丙二醇單丙醚乙酸酯、甲氧基丁基乙酸酯、甲氧基戊基乙酸酯等)，烷烴(例如己烷、庚烷、辛烷等)，苯或其衍生物(例如苯、甲苯、二甲苯等)，醚(例如二甘醇二甲醚、二甘醇二乙醚、二甘醇二丙醚、二甘醇二丁醚、丙二醇單甲醚等)等。溶劑可單獨使用或以兩種或更多種組合使用。 溶劑可為相對於在其上施塗有根據本發明之硬質塗層組合物之基板具有低溶解度的溶劑，且因此硬質塗佈組合物可在固化後容易地自基板剝離。 相對於100重量%之全部硬質塗佈組合物，該硬質塗佈組合物可包括10重量%至95重量%之溶劑。當溶劑之含量小於10重量%時，由於黏度之增加而可加工性會降低。另一方面，當其含量大於95重量%時，乾燥製程會需要較長時間，且經濟可行性會降低。光引發劑
光引發劑可任意使用而沒有限制，只要其在此項技術中使用，且可係選自由羥基酮、胺基酮及奪氫型光引發劑組成之群中之一或多者。 具體地，光引發劑可係2-甲基-1-[4-(甲硫基)苯基]-2-嗎啉基-1-丙酮、二苯基酮、苄基二甲基縮酮、2-羥基-2-甲基-1-苯基-1-酮、4-羥基環戊基酮、2,2-二甲氧基-2-苯基苯乙酮、蒽醌、茀、三苯胺、咔唑、3-甲基苯乙酮、4-氯苯乙酮、4,4-二甲氧基苯乙酮、4,4-二胺基二苯甲酮、1-羥基環己基-苯基-酮、二苯甲酮、二苯基(2,4,6-三甲基苯甲醯基)氧化膦等。此等者可單獨使用或以兩種或更多種之組合使用。 相對於100重量%之全部硬質塗佈組合物，該硬質塗佈組合物可包括0.1重量%至10重量%，較佳1重量%至5重量%之光引發劑。當光引發劑之含量小於0.1重量%時，硬質塗佈組合物之固化速度會減小，且由於固化速度下降導致之不充分固化，機械效能會降低。另一方面，當光引發劑之含量大於10重量%時，塗膜會由於過固化而破裂。添加劑
添加劑可包括選自由無機奈米顆粒、流平劑及穩定劑組成之群中之一或多者。(1) 無機奈米顆粒
可選擇性地添加無機奈米顆粒以改善硬質塗層之硬度。具體地，當在硬質塗膜組合物中包括無機奈米顆粒時，可進一步改善機械效能。更具體地，無機奈米顆粒均勻地形成在塗膜中，且因此可改善機械效能，例如耐磨性、抗刮傷性、鉛筆硬度等。 無機奈米顆粒可具有1 nm至100 nm，特別是1 nm至80 nm，更特別是5 nm至50 nm之平均直徑。當無機奈米顆粒之平均直徑在此等範圍內時，可防止在組合物中發生團聚之現象且因此形成均勻之塗膜，且防止塗膜之光學特性及機械效能之降低。 無機奈米顆粒可包括選自由Al2
O3
、SiO2
、ZnO、ZrO2
、BaTiO3
、TiO2
、Ta2
O5
、Ti3
O5
、ITO、IZO、ATO、ZnO-Al、Nb2
O3
、SnO、MgO及其組合組成之群中之一或多者，但是本發明不限於此。無機奈米顆粒可包括此項技術中通常使用之金屬氧化物。 具體地，無機奈米顆粒可係Al2
O3
、SiO2
或ZrO2
。無機奈米顆粒可直接製造，或者可係其中無機奈米顆粒以10重量%至80重量%之濃度分散在有機溶劑中之市售產品。(2) 流平劑
流平劑可包括選自由矽氧烷基流平劑、氟基流平劑及丙烯酸類流平劑組成之群中之一或多者。當在硬質塗膜組合物中包括流平劑時，在形成塗膜期間可賦予平滑性及塗佈性。 具體地，流平劑可係BYK-323、BYK-331、BYK-333、BYK-337、BYK-373、BYK-375、BYK-377或BYK-378，其等均可自BYK Chemie GmbH商購獲得；TEGO Glide 410、TEGO Glide 411、TEGO Glide 415、TEGO Glide 420、TEGO Glide 432、TEGO Glide 435、TEGO Glide 440、TEGO Glide 450、TEGO Glide 455、TEGO Rad 2100、TEGO Rad 2200N、TEGO Rad 2250、TEGO Rad 2300、TEGO Rad 2500，其等均可自Evonik TEGO Chemie GmbH商購獲得；FC-4430、FC-4432，其等均可自3M商購獲得，諸如此類，但本發明不限於此。可使用此項技術中常用之流平劑。(3) 穩定劑
穩定劑可包括選自由受阻胺、水楊酸苯酯、二苯甲酮、苯并三唑、鎳衍生物、自由基清除劑、多酚、亞磷酸酯及內酯穩定劑組成之群中之一或多者。 本文中使用之術語「UV穩定劑」係指為了藉由阻擋或吸收UV射線來保護黏合劑之目的而添加之添加劑，因為由於連續UV射線曝露引起之分解，塗膜之固化表面變色且容易破裂。 基於原理，UV穩定劑可分類為吸收劑、淬滅劑或受阻胺光穩定劑(HALS)。此外，基於化學結構，UV穩定劑可分類為水楊酸苯酯(吸收劑)、二苯甲酮(吸收劑)、苯并三唑(吸收劑)、鎳衍生物(淬滅劑)或自由基清除劑。 然而，本發明不特別限於此，只要UV穩定劑不顯著改變黏合劑之初始顏色即可。 作為商業上可應用之產品之熱穩定劑，可單獨或組合使用多酚(主要熱穩定劑)及亞磷酸酯及內酯(次要熱穩定劑)。UV穩定劑及熱穩定劑可藉由在不影響UV固化效能之水準下適當調節其含量來使用。 ＜硬質塗膜＞ 在本發明之另一個示例性實施方式中，在透明基板上形成硬質塗佈組合物之固化產物以製造硬質塗膜。 在此情況下，硬質塗佈組合物之固化產物之厚度為50 μm至300 μm。當硬質塗佈組合物之固化產物之厚度小於50 μm時，抗衝擊性會降低。另一方面，當其厚度大於300 μm時，抗彎曲性會降低。基板
將根據本發明之硬質塗佈組合物施塗在基板之一個表面上、固化、剝離，然後轉移至其他所需之基板。 此外，將根據本發明之硬質塗佈組合物施塗在基板之一個表面上、固化、剝離，然後使用黏著劑(sticking agent)或黏合劑(adhesive)轉移至其他所需之基板。 在本發明中，其上施塗有硬質塗佈組合物之基板可係此項技術中使用之任何基板，例如透明基板。 透明基板可係具有透明性之任何聚合物膜。 具體地，透明基板可為由以下聚合物製成之膜：例如具有含環烯烴單體(例如降冰片烯或多環降冰片烯基單體)之環烯烴衍生物，纖維素(例如二乙醯纖維素、三乙醯纖維素、乙醯纖維素丁酸酯、異丁酯纖維素、丙醯纖維素、丁醯纖維素或乙醯丙醯纖維素)，乙烯/乙酸乙烯酯共聚物、聚環烯烴、聚酯、聚苯乙烯、聚醯胺、聚醚醯亞胺、聚丙烯酸、聚醯亞胺、聚醚碸、聚碸、聚乙烯、聚丙烯、聚甲基戊烯、聚氯乙烯、聚偏氯乙烯、聚乙烯醇、聚乙烯醇縮醛、聚醚酮、聚醚醚酮、聚甲基丙烯酸甲酯、聚對苯二甲酸乙二酯、聚對苯二甲酸丁二酯、聚萘二甲酸乙二酯、聚碳酸酯、聚胺酯、環氧樹脂等，且亦可為未取向膜或單軸取向膜或雙軸取向膜。此等聚合物可單獨使用或以兩種或更多種之組合使用。 在透明基板中，可較佳使用具有優異之透明性及耐熱性之單軸或雙軸取向聚酯膜、具有優異之透明性及耐熱性且能夠支撐大尺寸膜之環烯烴衍生物膜及聚甲基丙烯酸甲酯膜、及具有透明性且不具有光學各向異性之三乙醯纖維素膜及異丁酯纖維素膜。 根據本發明之硬質塗佈組合物可以藉由在基板之一個表面上施塗硬質塗佈組合物、將硬質塗佈組合物固化、然後除去基板而形成之無基板硬質塗層之狀態使用。無基板硬質塗層可用於剛性或可撓性顯示器。具體地，硬質塗佈組合物可用作顯示器(例如LCD、OLED、LED、FED等)之蓋板玻璃、使用該顯示器之各種移動通信終端、智慧型電話或平板電腦之觸摸面板、電子紙等之功能層或替代品。 本發明提供一種包括無基板硬質塗層之圖像顯示裝置。 另外，本發明提供一種包括無基板硬質塗層之可撓性顯示裝置之視窗。 在下文中，將描述本發明之較佳實施方式，以幫助理解本發明。然而，對於熟習此項技術者顯而易見的是，此處提出之描述僅僅係用於說明之目的之較佳實施例，且不旨在限制或限定本發明之範圍。因此，應當理解，在不脫離本發明之範圍之情況下，可對本發明之示例性實施方式進行各種改變及修改，使得本發明覆蓋所提供之所有此等改變及修改，且其等在所附申請專利範圍及其等同物之範圍之內。以下，除非另有說明，否則表示實施例及比較實施例中之含量之所有「百分比」及「份」均以重量計。製備實施例 1 至 7 ：硬質塗佈組合物之製備 製備實施例 1
將70重量份之胺基甲酸酯丙烯酸酯(UA-122P，自Shin-Nakamura Chemical Co., Ltd.商購得)、25重量份之甲基乙基酮、4.5重量份之光引發劑(1-羥基環己基-苯基-酮)、及0.5重量份之流平劑(BYK-3570，自BYK Chemie GmbH商購得)使用攪拌器混合，且使用由聚丙烯(PP)製成之過濾器過濾以製備硬質塗佈組合物。此處，胺基甲酸酯丙烯酸酯之彈性模數為2070 MPa，斷裂伸長率為58%。製備實施例 2
將70重量份之胺基甲酸酯丙烯酸酯(UA-232P，自Shin-Nakamura Chemical Co., Ltd.商購得)、25重量份之甲基乙基酮、4.5重量份之光引發劑(1-羥基環己基-苯基-酮)、及0.5重量份之流平劑(BYK-3570，自BYK Chemie GmbH商購得)使用攪拌器混合，且使用由聚丙烯(PP)製成之過濾器過濾以製備硬質塗佈組合物。此處，胺基甲酸酯丙烯酸酯之彈性模數為1320 MPa，斷裂伸長率為135%。製備實施例 3
將70重量份之胺基甲酸酯丙烯酸酯(UA-122P，自Shin-Nakamura Chemical Co., Ltd.商購得)、25重量份之甲基乙基酮、4.5重量份之光引發劑(1-羥基環己基-苯基-酮)、及0.5重量份之流平劑(BYK-3570，自BYK Chemie GmbH商購得)使用攪拌器混合，且使用由聚丙烯(PP)製成之過濾器過濾以製備硬質塗佈組合物。此處，胺基甲酸酯丙烯酸酯之彈性模數為2570 MPa，斷裂伸長率為67%。製備實施例 4
將50重量份之胺基甲酸酯丙烯酸酯(UA-122P，自Shin-Nakamura Chemical Co., Ltd.商購得)、20重量份之季戊四醇三丙烯酸酯、25重量份之甲基乙基酮、4.5重量份之光引發劑(1-羥基環己基-苯基-酮)、及0.5重量份之流平劑(BYK-3570，自BYK Chemie GmbH商購得)使用攪拌器混合，且使用由聚丙烯(PP)製成之過濾器過濾以製備硬質塗佈組合物。此處，胺基甲酸酯丙烯酸酯與季戊四醇三丙烯酸酯之混合物之彈性模數為3220 MPa，斷裂伸長率為12%。製備實施例 5
將35重量份之胺基甲酸酯丙烯酸酯(UA-122P，自Shin-Nakamura Chemical Co., Ltd.商購得)、35重量份之季戊四醇三丙烯酸酯、25重量份之甲基乙基酮、4.5重量份之光引發劑(1-羥基環己基-苯基-酮)、及0.5重量份之流平劑(BYK-3570，自BYK Chemie GmbH商購得)使用攪拌器混合，且使用由聚丙烯(PP)製成之過濾器過濾以製備硬質塗佈組合物。此處，胺基甲酸酯丙烯酸酯與季戊四醇三丙烯酸酯之混合物之彈性模數為3705 MPa，斷裂伸長率為7%。製備實施例 6
將20重量份之胺基甲酸酯丙烯酸酯(UA-122P，自Shin-Nakamura Chemical Co., Ltd.商購得)、50重量份之季戊四醇三丙烯酸酯、25重量份之甲基乙基酮、4.5重量份之光引發劑(1-羥基環己基-苯基-酮)、及0.5重量份之流平劑(BYK-3570，自BYK Chemie GmbH商購得)使用攪拌器混合，且使用由聚丙烯(PP)製成之過濾器過濾以製備硬質塗佈組合物。此處，胺基甲酸酯丙烯酸酯與季戊四醇三丙烯酸酯之混合物之彈性模數為4210 MPa，斷裂伸長率為5%。製備實施例 7
將35重量份之胺基甲酸酯丙烯酸酯(UA-122P，自Shin-Nakamura Chemical Co., Ltd.商購得)、35重量份之二季戊四醇六丙烯酸酯、25重量份之甲基乙基酮、4.5重量份之光引發劑(1-羥基環己基-苯基-酮)、及0.5重量份之流平劑(BYK-3570，自BYK Chemie GmbH商購得)使用攪拌器混合，且使用由聚丙烯(PP)製成之過濾器過濾以製備硬質塗佈組合物。此處，胺基甲酸酯丙烯酸酯與二季戊四醇六丙烯酸酯之混合物之彈性模數為4570 MPa，斷裂伸長率為3%。實施例 1 至 5 及比較實施例 1 至 6 ：硬質塗層之製造 實施例 1
將製備實施例1中製備之硬質塗佈組合物以使得固化後之組合物的厚度為200 μm之此類方式施塗在厚度為50 μm之聚酯(PET)基膜上。在塗佈膜之後，乾燥溶劑且以500 mJ/cm2
之整合光強度照射UV射線，以使組合物固化，從而製造硬質塗膜。然後，剝離聚酯(PET)基膜，以製造具有抗衝擊性之無基板硬質塗層。實施例 2
除了使用製備實施例2中製備之硬質塗佈組合物外，以與實施例1相同之方式製造硬質塗層。實施例 3
除了使用製備實施例3中製備之硬質塗佈組合物外，以與實施例1相同之方式製造硬質塗層。實施例 4
除了固化後硬質塗層之厚度為70 μm外，以與實施例1相同之方式製造硬質塗層。實施例 5
除了固化後硬質塗層之厚度為250 μm外，以與實施例1相同之方式製造硬質塗層。比較實施例 1
除了使用製備實施例4中製備之硬質塗佈組合物外，以與實施例1相同之方式製造硬質塗層。比較實施例 2
除了使用製備實施例5中製備之硬質塗佈組合物外，以與實施例1相同之方式製造硬質塗層。比較實施例 3
除了使用製備實施例6中製備之硬質塗佈組合物外，以與實施例1相同之方式製造硬質塗層。比較實施例 4
除了使用製備實施例7中製備之硬質塗佈組合物外，以與實施例1相同之方式製造硬質塗層。比較實施例 5
除了固化後硬質塗層之厚度為10 μm外，以與實施例1相同之方式製造硬質塗層。比較實施例 6
除了固化後硬質塗層之厚度為350 μm外，以與實施例1相同之方式製造硬質塗層。實驗實施例
實施例1至5及比較實施例1至6中製造之硬質塗層之性質以如下方式測定，其結果示於表1。本發明中使用之測定方法及評價方法如下。 (1)抗彎曲性 將實施例及比較實施例中製造之硬質塗層對折以在其表面之間具有6 mm之間距。然後，藉由肉眼觀察及確定該膜再次展開時摺疊部分是否發生破裂，其結果示於下表1中。 良好：在摺疊部分沒有破裂 不合格：在摺疊部分破裂 (2)抗衝擊性 使用50 μm光學透明黏合劑(OCA) (彈性模數為0.08 MPa)將實施例及比較實施例中製造之硬質塗層黏附至玻璃上。然後，當將鋼球自50 cm之高度自由地落在硬質塗層之表面上時，測定未破壞硬質塗膜下方之玻璃之該鋼球的最大重量，其結果示於下表1中。 [表1]
參考表1，證實了與其中顯示出彈性模數及斷裂伸長率在本發明範圍之外的比較實施例1至4相比，在其中顯示出彈性模數及斷裂伸長率在本發明範圍之內之實施例1至5之情況下表現出優異之抗彎曲性及抗衝擊性。 另外，證實了與其中硬質塗佈組合物之固化產物之厚度高於較佳範圍(50 μm至300 μm)的比較實施例6相比，在其中硬質塗佈組合物之固化產物之厚度在上述範圍內的實施例1至5之情況下表現出優異之抗彎曲性，且在其中硬質塗佈組合物之固化產物之厚度低於上述範圍的比較實施例5之情況下，由於硬質塗佈組合物之固化產物之厚度不足，難以自基板剝離硬質塗佈組合物之固化產物。In the present invention, when a part “includes” an element, unless otherwise described, another element may also be included without excluding the existence of the other element. Hereinafter, the present invention will be described in detail with reference to exemplary embodiments. < Hard Coating Composition > The hard coating composition according to an exemplary embodiment of the present invention includes a high elongation oligomer having an elastic modulus of 10 MPa to 3000 MPa and an elongation at break of 30% to 150%. . When the hard coating composition has an elastic modulus and an elongation at break within these ranges, it can exhibit excellent bending resistance and impact resistance. High elongation oligomer The hard coating composition according to the present invention includes a high elongation oligomer. High elongation oligomers include photocurable (meth) acrylate oligomers. The photocurable (meth) acrylate oligomer may include one selected from the group consisting of epoxy (meth) acrylate, urethane (meth) acrylate, and polyester (meth) acrylate One or more. An epoxy (meth) acrylate can be obtained by reacting a carboxylic acid having a (meth) acrylfluorenyl group with an epoxy compound. Specifically, the epoxy compound may be glycidyl (meth) acrylate, C 1 to C 12 linear alcohol-terminated glycidyl ether, diethylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, bisphenol A Diglycidyl ether, ethylene oxide modified bisphenol A diglycidyl ether, propylene oxide modified bisphenol A diglycidyl ether, trimethylolpropane triglycidyl ether, pentaerythritol tetraglycidyl ether, Hydrogenated bisphenol A diglycidyl ether, glycerol diglycidyl ether, and the like. The carboxylic acid having a (meth) acrylfluorenyl group may be (meth) acrylic acid, 2- (meth) acryloxyethyl succinic acid, 2- (meth) acryloxyethyl hexahydroo-benzene Dicarboxylic acid and so on. The urethane (meth) acrylate can be prepared by reacting a polyfunctional (meth) acrylate having a hydroxyl group in the molecule and a compound having an isocyanate group in the presence of a catalyst. The (meth) acrylate having a hydroxyl group in the molecule may be selected from the group consisting of 2-hydroxyethyl (meth) acrylate, 2-hydroxyisopropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, Caprolactone ring-opening hydroxy acrylate, a mixture of pentaerythritol tri (meth) acrylate and pentaerythritol tetra- (meth) acrylate, and dipentaerythritol penta-tetra (meth) acrylate and dipentaerythritol hexa- (methyl ) One or more of the group consisting of a mixture of acrylates. The compound having an isocyanate group in the molecule may be one or more selected from the group consisting of: 1,4-diisocyanatobutane, 1,6-diisocyanatohexane, 1,8- Diisocyanate octane, 1,12-diisocyanatododecane, 1,5-diisocyanato-2-methylpentane, trimethyl-1,6-diisocyanate Hexane, 1,3-bis (isocyanatomethyl) cyclohexane, trans-1,4-cyclohexane diisocyanate, 4,4'-methylenebis (cyclohexyl isocyanate), isophor Ketone diisocyanate, toluene-2,4-diisocyanate, toluene-2,6-diisocyanate, xylene-1,4-diisocyanate, tetramethylxylene-1,3-diisocyanate, 1-chloromethyl -2,4-diisocyanate, 4,4'-methylenebis (2,6-dimethylphenyl isocyanate), 4,4'-oxybis (phenyl isocyanate), derived from hexamethylene di Isocyanate trifunctional isocyanate and trimethylpropanol-toluene diisocyanate adduct. Polyester (meth) acrylate, specifically, a diacrylate (e.g., ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate Ester, polyethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, 1,4-butanediol Di (meth) acrylate, neopentyl glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, tricyclodecane di (meth) acrylate, bisphenol A Di (meth) acrylate, etc.), trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, bistrimethylolpropane tetra (methyl) Acrylate), dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, tris (2- (meth) acryloxyethyl) isocyanurate, and the like. It is preferable to use a urethane (meth) acrylate and a polyester (meth) acrylate in combination, or to include both a polyester group and a urethane group in one molecule. In particular, an acrylate oligomer having a linear structure can be used to form a hard coating film having an elongation of 30% or more. Preferably, a polyester (meth) acrylate having a linear structure and exhibiting excellent flexibility is used. The hard coating composition may preferably include a high elongation oligomer of 1 to 90% by weight, more preferably 5 to 80% by weight, relative to 100% by weight of the entire hard coating composition. When the content of the high elongation oligomer is less than 1% by weight, it is difficult to form a coating film, or even if a coating film is formed, it is difficult to produce a hard coating composition having a sufficient level of impact resistance. On the other hand, when the content of the high elongation oligomer is more than 90% by weight, the uniformity of the coating film may decrease due to the high viscosity during the production of the hard coating film using the hard coating composition. In an exemplary embodiment of the present invention, the hard coating composition may further include one or more selected from the group consisting of a solvent, a photoinitiator, and an additive. Solvent A solvent is a material that can dissolve or disperse the above composition, and can be used without limitation, as long as it is a solvent for a hard coating composition known in the art. Specifically, the solvent may preferably be an alcohol (for example, methanol, ethanol, isopropanol, butanol, methyl cellosolve, ethyl cellosolve, etc.), and a ketone (e.g. methyl ethyl ketone, methyl butyl ketone) , Methyl isobutyl ketone, diethyl ketone, dipropyl ketone, cyclohexanone, etc.), acetate (e.g. ethyl acetate, propyl acetate, n-butyl acetate, third butyl acetate, methyl Cellosolve acetate, ethylcellosolve acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, methoxybutyl acetate, methoxy Pentyl acetate, etc.), alkanes (such as hexane, heptane, octane, etc.), benzene or its derivatives (such as benzene, toluene, xylene, etc.), ethers (such as diglyme, Glycol diethyl ether, diethylene glycol dipropyl ether, diethylene glycol dibutyl ether, propylene glycol monomethyl ether, etc.). The solvent may be used alone or in a combination of two or more. The solvent may be a solvent having a low solubility with respect to a substrate on which the hard coating composition according to the present invention is applied, and thus the hard coating composition can be easily peeled from the substrate after curing. The hard coating composition may include 10 to 95% by weight of a solvent relative to 100% by weight of the entire hard coating composition. When the content of the solvent is less than 10% by weight, the workability is reduced due to an increase in viscosity. On the other hand, when the content is more than 95% by weight, the drying process may take a long time, and the economic feasibility may decrease. Photoinitiator The photoinitiator can be used without any limitation as long as it used in the art, and may be selected from the group consisting of hydroxy ketone, amino ketone, and hydrogen abstraction-type photoinitiator group consisting of one or more agents. Specifically, the photoinitiator may be 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinyl-1-acetone, diphenyl ketone, benzyl dimethyl ketal, 2-hydroxy-2-methyl-1-phenyl-1-one, 4-hydroxycyclopentyl ketone, 2,2-dimethoxy-2-phenylacetophenone, anthraquinone, fluorene, triphenylamine , Carbazole, 3-methylacetophenone, 4-chloroacetophenone, 4,4-dimethoxyacetophenone, 4,4-diaminobenzophenone, 1-hydroxycyclohexyl-benzene Ketone-ketone, benzophenone, diphenyl (2,4,6-trimethylbenzyl) phosphine oxide and the like. These may be used alone or in a combination of two or more. The hard coating composition may include 0.1 to 10% by weight, preferably 1 to 5% by weight of the photoinitiator, relative to 100% by weight of the entire hard coating composition. When the content of the photoinitiator is less than 0.1% by weight, the curing speed of the hard coating composition is reduced, and insufficient curing is caused due to the decrease in the curing speed, and the mechanical efficiency is reduced. On the other hand, when the content of the photoinitiator is more than 10% by weight, the coating film may be cracked due to over-curing. Additives The additives may include one or more selected from the group consisting of inorganic nano particles, leveling agents, and stabilizers. (1) Inorganic nano particles You can optionally add inorganic nano particles to improve the hardness of the hard coating. Specifically, when inorganic nano particles are included in the hard coating film composition, the mechanical efficiency can be further improved. More specifically, the inorganic nano particles are uniformly formed in the coating film, and thus mechanical properties such as abrasion resistance, scratch resistance, pencil hardness, and the like can be improved. The inorganic nanoparticle may have an average diameter of 1 nm to 100 nm, particularly 1 nm to 80 nm, and more particularly 5 nm to 50 nm. When the average diameter of the inorganic nano particles is within these ranges, it is possible to prevent the phenomenon of agglomeration in the composition and thus to form a uniform coating film, and prevent the optical characteristics and mechanical efficiency of the coating film from being lowered. The inorganic nano particles may include a material selected from the group consisting of Al 2 O 3 , SiO 2 , ZnO, ZrO 2 , BaTiO 3 , TiO 2 , Ta 2 O 5 , Ti 3 O 5 , ITO, IZO, ATO, ZnO-Al, Nb 2 O 3. One or more of the group consisting of SnO, MgO and combinations thereof, but the present invention is not limited thereto. Inorganic nano particles may include metal oxides commonly used in the art. Specifically, the inorganic nano particles may be Al 2 O 3 , SiO 2 or ZrO 2 . The inorganic nano particles may be directly manufactured, or may be a commercially available product in which the inorganic nano particles are dispersed in an organic solvent at a concentration of 10% to 80% by weight. (2) Leveling agent The leveling agent may include one or more selected from the group consisting of a siloxane-based leveling agent, a fluorine-based leveling agent, and an acrylic leveling agent. When a leveling agent is included in the hard coating film composition, smoothness and coatability can be imparted during the formation of the coating film. Specifically, the leveling agent may be BYK-323, BYK-331, BYK-333, BYK-337, BYK-373, BYK-375, BYK-377 or BYK-378, all of which are commercially available from BYK Chemie GmbH Get; TEGO Glide 410, TEGO Glide 411, TEGO Glide 415, TEGO Glide 420, TEGO Glide 432, TEGO Glide 435, TEGO Glide 440, TEGO Glide 450, TEGO Glide 455, TEGO Rad 2100, TEGO Rad 2200N, TEGO Rad 2250, TEGO Rad 2300, TEGO Rad 2500, etc. are all commercially available from Evonik TEGO Chemie GmbH; FC-4430, FC-4432, etc. are all commercially available from 3M, and the like, but the present invention is not limited thereto. Leveling agents commonly used in this technology can be used. (3) Stabilizer stabilizers may include stabilizers selected from hindered amines, phenylsalicylate, benzophenone, benzotriazole, nickel derivatives, free radical scavengers, polyphenols, phosphites, and lactone stabilizers One or more of the group. The term "UV stabilizer" as used herein refers to an additive added for the purpose of protecting the adhesive by blocking or absorbing UV rays, because the cured surface of the coating film discolors and easily breaks due to decomposition caused by continuous UV rays exposure. . Based on the principle, UV stabilizers can be classified as absorbers, quenchers or hindered amine light stabilizers (HALS). In addition, based on chemical structure, UV stabilizers can be classified as phenylsalicylate (absorber), benzophenone (absorber), benzotriazole (absorber), nickel derivative (quenching agent), or free Based scavenger. However, the present invention is not particularly limited as long as the UV stabilizer does not significantly change the initial color of the adhesive. As heat stabilizers for commercially available products, polyphenols (main heat stabilizers) and phosphites and lactones (secondary heat stabilizers) can be used alone or in combination. UV stabilizers and thermal stabilizers can be used by appropriately adjusting their content without affecting the level of UV curing performance. <Hard Coating Film> In another exemplary embodiment of the present invention, a cured product of a hard coating composition is formed on a transparent substrate to produce a hard coating film. In this case, the thickness of the cured product of the hard coating composition is 50 μm to 300 μm. When the thickness of the cured product of the hard coating composition is less than 50 μm, impact resistance may be reduced. On the other hand, when the thickness is more than 300 μm, the bending resistance is reduced. Substrate The hard coating composition according to the present invention is applied to one surface of a substrate, cured, peeled, and then transferred to other desired substrates. In addition, the hard coating composition according to the present invention is applied to one surface of a substrate, cured, peeled, and then transferred to other desired substrates using a sticking agent or adhesive. In the present invention, the substrate on which the hard coating composition is applied may be any substrate used in the technology, such as a transparent substrate. The transparent substrate may be any polymer film having transparency. Specifically, the transparent substrate may be a film made of a polymer such as a cyclic olefin derivative having a cyclic olefin-containing monomer (for example, norbornene or polycyclic norbornene-based monomer), and cellulose (for example, diethyl Cellulose, triethyl cellulose, ethyl cellulose butyrate, isobutyl cellulose, propyl cellulose, butyl cellulose, or ethionic cellulose), ethylene / vinyl acetate copolymer, Polycyclic olefins, polyesters, polystyrenes, polyfluorenes, polyetherimines, polyacrylic acids, polyimides, polyethers, polyfluorenes, polyethylenes, polypropylenes, polymethylpentenes, polychlorines Ethylene, polyvinylidene chloride, polyvinyl alcohol, polyvinyl acetal, polyether ketone, polyether ether ketone, polymethyl methacrylate, polyethylene terephthalate, polybutylene terephthalate , Polyethylene naphthalate, polycarbonate, polyurethane, epoxy resin, etc., and may also be an unoriented film, a uniaxially oriented film, or a biaxially oriented film. These polymers may be used alone or in a combination of two or more. Among the transparent substrates, uniaxially or biaxially oriented polyester films having excellent transparency and heat resistance, cycloolefin derivative films having excellent transparency and heat resistance, and being capable of supporting large-sized films, and polymers can be preferably used. A methyl methacrylate film, and a triethyl cellulose film and an isobutyl cellulose film having transparency and no optical anisotropy. The hard coating composition according to the present invention can be used in a state of a substrate-free hard coating layer formed by applying a hard coating composition on one surface of a substrate, curing the hard coating composition, and then removing the substrate. Substrate-free hard coatings can be used for rigid or flexible displays. Specifically, the hard coating composition can be used as a cover glass for a display (e.g., LCD, OLED, LED, FED, etc.), various mobile communication terminals using the display, a touch panel of a smart phone or tablet, electronic paper, etc. Functional layers or alternatives. The invention provides an image display device including a substrate-less hard coating layer. In addition, the present invention provides a window for a flexible display device including a substrate-less hard coating. Hereinafter, preferred embodiments of the present invention will be described to help understand the present invention. However, it is obvious to those skilled in the art that the description presented here is only a preferred embodiment for the purpose of illustration, and is not intended to limit or limit the scope of the present invention. Therefore, it should be understood that various changes and modifications can be made to the exemplary embodiments of the present invention without departing from the scope of the present invention, so that the present invention covers all such changes and modifications provided, and the attached Within the scope of patent applications and their equivalents. Hereinafter, unless otherwise stated, all "percentages" and "parts" that represent the contents in the examples and comparative examples are by weight. Preparation Examples 1 to 7 : Preparation of Hard Coating Compositions Preparation Example 1 70 parts by weight of urethane acrylate (UA-122P, commercially available from Shin-Nakamura Chemical Co., Ltd.), 25 parts by weight of methyl ethyl ketone, 4.5 parts by weight of a photoinitiator (1-hydroxycyclohexyl-phenyl-one), and 0.5 parts by weight of a leveling agent (BYK-3570, commercially available from BYK Chemie GmbH ) Mix using a stirrer and filter using a filter made of polypropylene (PP) to prepare a hard coating composition. Here, the elastic modulus of the urethane acrylate is 2070 MPa, and the elongation at break is 58%. Preparation Example 2 70 parts by weight of urethane acrylate (UA-232P, commercially available from Shin-Nakamura Chemical Co., Ltd.), 25 parts by weight of methyl ethyl ketone, and 4.5 parts by weight of A photoinitiator (1-hydroxycyclohexyl-phenyl-one) and a leveling agent (BYK-3570, commercially available from BYK Chemie GmbH) in an amount of 0.5 parts by weight were mixed using a stirrer, and polypropylene (PP) was used. The manufactured filter was filtered to prepare a hard coating composition. Here, the elastic modulus of the urethane acrylate is 1,320 MPa, and the elongation at break is 135%. Preparation Example 3 70 parts by weight of urethane acrylate (UA-122P, commercially available from Shin-Nakamura Chemical Co., Ltd.), 25 parts by weight of methyl ethyl ketone, and 4.5 parts by weight of A photoinitiator (1-hydroxycyclohexyl-phenyl-one) and a leveling agent (BYK-3570, commercially available from BYK Chemie GmbH) in an amount of 0.5 parts by weight were mixed using a stirrer, and polypropylene (PP) was used. The manufactured filter was filtered to prepare a hard coating composition. Here, the elastic modulus of the urethane acrylate is 2570 MPa, and the elongation at break is 67%. Production Example 4 50 parts by weight of urethane acrylate (UA-122P, commercially available from Shin-Nakamura Chemical Co., Ltd.), 20 parts by weight of pentaerythritol triacrylate, and 25 parts by weight of formazan Methyl ethyl ketone, 4.5 parts by weight of a photoinitiator (1-hydroxycyclohexyl-phenyl-one), and 0.5 parts by weight of a leveling agent (BYK-3570, commercially available from BYK Chemie GmbH) were mixed using a stirrer And filtered using a filter made of polypropylene (PP) to prepare a hard coating composition. Here, the elastic modulus of the mixture of the urethane acrylate and pentaerythritol triacrylate is 3220 MPa, and the elongation at break is 12%. Preparation Example 5 35 parts by weight of urethane acrylate (UA-122P, commercially available from Shin-Nakamura Chemical Co., Ltd.), 35 parts by weight of pentaerythritol triacrylate, and 25 parts by weight of formazan Methyl ethyl ketone, 4.5 parts by weight of a photoinitiator (1-hydroxycyclohexyl-phenyl-one), and 0.5 parts by weight of a leveling agent (BYK-3570, commercially available from BYK Chemie GmbH) were mixed using a stirrer And filtered using a filter made of polypropylene (PP) to prepare a hard coating composition. Here, the elastic modulus of the mixture of the urethane acrylate and pentaerythritol triacrylate is 3705 MPa, and the elongation at break is 7%. Production Example 6 20 parts by weight of urethane acrylate (UA-122P, commercially available from Shin-Nakamura Chemical Co., Ltd.), 50 parts by weight of pentaerythritol triacrylate, and 25 parts by weight of formazan Methyl ethyl ketone, 4.5 parts by weight of a photoinitiator (1-hydroxycyclohexyl-phenyl-one), and 0.5 parts by weight of a leveling agent (BYK-3570, commercially available from BYK Chemie GmbH) were mixed using a stirrer And filtered using a filter made of polypropylene (PP) to prepare a hard coating composition. Here, the elastic modulus of the mixture of the urethane acrylate and pentaerythritol triacrylate is 4210 MPa, and the elongation at break is 5%. Preparation Example 7 35 parts by weight of urethane acrylate (UA-122P, commercially available from Shin-Nakamura Chemical Co., Ltd.), 35 parts by weight of dipentaerythritol hexaacrylate, and 25 parts by weight of Methyl ethyl ketone, 4.5 parts by weight of a photoinitiator (1-hydroxycyclohexyl-phenyl-one), and 0.5 parts by weight of a leveling agent (BYK-3570, commercially available from BYK Chemie GmbH) using a stirrer Mix and filter using a filter made of polypropylene (PP) to prepare a hard coating composition. Here, the elastic modulus of the mixture of the urethane acrylate and dipentaerythritol hexaacrylate is 4570 MPa, and the elongation at break is 3%. Examples 1 to 5 and Comparative Examples 1 to 6: Production Example 1 A hard coat layer of thickness 1 embodiment the hard coating composition prepared in Preparation Example of such compositions after curing of 200 μm was such a way as It is applied on a polyester (PET) base film with a thickness of 50 μm. After the film is coated, the solvent is dried and irradiated with UV rays at an integrated light intensity of 500 mJ / cm 2 to cure the composition, thereby producing a hard coating film. Then, the polyester (PET) -based film is peeled off to produce a substrate-less hard coating layer having impact resistance. Example 2 A hard coating layer was produced in the same manner as in Example 1 except that the hard coating composition prepared in Preparation Example 2 was used. Example 3 A hard coat layer was produced in the same manner as in Example 1 except that the hard coating composition prepared in Preparation Example 3 was used. Example 4 A hard coating was manufactured in the same manner as in Example 1 except that the thickness of the hard coating after curing was 70 μm. Example 5 A hard coating was produced in the same manner as in Example 1 except that the thickness of the hard coating after curing was 250 μm. Comparative Example 1 produced a hard coat layer in the same manner as in Example 1, except that the hard coating composition prepared in Preparation Example 4 was used. Comparative Example 2 produced a hard coat layer in the same manner as in Example 1 except that the hard coating composition prepared in Preparation Example 5 was used. Comparative Example 3 produced a hard coat layer in the same manner as in Example 1 except that the hard coating composition prepared in Preparation Example 6 was used. Comparative Example 4 produced a hard coat layer in the same manner as in Example 1 except that the hard coating composition prepared in Preparation Example 7 was used. Comparative Example 5 A hard coating was manufactured in the same manner as in Example 1 except that the thickness of the hard coating after curing was 10 μm. Comparative Example 6 A hard coating was produced in the same manner as in Example 1 except that the thickness of the hard coating after curing was 350 μm. Experimental Examples The properties of the hard coat layers produced in Examples 1 to 5 and Comparative Examples 1 to 6 were measured in the following manner, and the results are shown in Table 1. The measurement methods and evaluation methods used in the present invention are as follows. (1) Bending resistance The hard coating layers produced in the examples and comparative examples were folded in half to have a distance of 6 mm between their surfaces. Then, whether or not the folded portion was broken when the film was unfolded again was observed and confirmed with the naked eye, and the results are shown in Table 1 below. Good: No rupture in the folded portion. Unqualified: rupture in the folded portion. (2) Impact resistance. Hard coatings produced in the examples and comparative examples were produced using 50 μm optically clear adhesive (OCA) (elastic modulus 0.08 MPa) The layer is adhered to the glass. Then, when the steel ball was dropped freely on the surface of the hard coating layer from a height of 50 cm, the maximum weight of the steel ball without damaging the glass under the hard coating film was measured, and the results are shown in Table 1 below. [Table 1] With reference to Table 1, it was confirmed that compared with Comparative Examples 1 to 4 in which the elastic modulus and the elongation at break were shown to be outside the range of the present invention, it was shown that the elastic modulus and the elongation at break were within the range of the present invention Examples 1 to 5 exhibited excellent bending resistance and impact resistance. In addition, it was confirmed that compared with Comparative Example 6 in which the thickness of the cured product of the hard coating composition was higher than the preferred range (50 μm to 300 μm), the thickness of the cured product of the hard coating composition was within the above range. Examples 1 to 5 in the range exhibit excellent bending resistance, and in the case of Comparative Example 5 in which the thickness of the cured product of the hard coating composition is lower than the above range, due to the hard coating combination The thickness of the cured product of the product is insufficient to make it difficult to peel the cured product of the hard coating composition from the substrate.