201221544 六、發明說明 【發明所屬之技術領域】 本發明有關對苯二甲酸-1,4-環己烷二甲醇酯與間苯二 甲酸-1,4-環己烷二甲醇酯之共聚合物薄膜、太陽能電池模 組用保護片、及太陽能電池模組。 【先前技術】 作爲替代化石燃料之潔淨的能源，太陽能電池發電 系統正受人期待。一般，在太陽能電池發電系統中，採用 經將數個至數十個太陽能電池元件配線爲串聯或並聯之元 件群使用種種組件加以保護之太陽能電池模組。一般，太 陽能電池模組，係作成爲太陽光直接照射之面爲被白紙板 強化玻璃（white board reinforced glass)所被覆，於其下面 配置有太陽能電池元件群、而利用透明的伸乙基•乙烯 基*乙酸酯樹脂等塡埋其間隙、背面則被耐氣候性塑膠材 料等的片材所保護之構成（例如，專利文獻1及2)。 由於太陽能電池模組係在屋外所使用之故，於其構 成，材質構造等，需要具有充分的耐久性、耐氣候性。特 '別是，爲太陽能電池模組的保護片（特別是背面保護片）， •需要具有耐氣候性，尤其是耐水解性。此乃由於長期間在 屋外使用中保護片被雨水等的水分所分解•剝離，並因而 暴露之配線發生腐蝕而模組之輸出（output)可能受影響之 故。 [先前技術文獻] -5- 201221544 [專利文獻] 專利文獻1:日本專利特開2000-243999號公報 專利文獻2 :日本專利特開2008 _23 5603號公報 【發明內容】 [發明所欲解決之課題] 作爲太陽能電池模組用背面保護片的基材，有種種薄 膜材料之硏究，惟耐水解性良好的薄膜材料則至今尙未曾 開發。 例如，聚對苯二甲酸乙二醇酯（PET)薄膜或聚萘二甲 酸乙二醇酯（PEN)薄膜，係耐水解性不足夠，而不堪作爲 太陽能電池膜組用背面保護片的基材實用者。 於是’本發明之目的在於提供一種耐水解性優異的薄 膜、採用該薄膜之太陽能電池模組用保護片及太陽能電池 膜組。 [用以解決課題之手段] 經本發明人專心硏究之結果發現，特定的對苯二甲 酸-1,4 -環己烷二甲醇酯與間苯二甲酸-1，4·環己烷二甲醇 酯之共聚合物薄膜係耐水解性優異，並適合於太陽能電池 模組用保護片的基材之事實，而完成本發明。 本發明提供一種依DMA(黏彈性測定裝置）法所測定之 玻璃化溫度爲130 °C以上之對苯二甲酸-1，4-環己烷二甲醇 酯與間苯二甲酸-1，4-環己烷二甲醇酯之共聚合物薄膜。 • 6 - 201221544 又’本發明提供一種依TMA(熱機分析器）法所測定之 玻璃化溫度爲200C以上之對苯二甲酸-1，4 -環己垸二甲醇 酯與間苯二甲酸-1,4 -環己院二甲醇酯之共聚合物薄膜。 又，本發明提供一種於X射線繞射（x_ray diffracti〇n) 中，在22°S20S24°的範圍具有最大峰値之對苯二甲酸_ 1.4 -環己烷二甲醇酯與間苯二甲酸_1,4_環己烷二甲醇醋之 共聚合物薄膜。 此等對苯二甲酸-1,4 -環己院二甲醇酯與間苯二甲酸_ 1.4 -環己烷二甲醇酯之共聚合物薄膜，係而水解性優異 者。 本發明提供一種至少含有一層上述任一對苯一甲酸-1，4-環己烷二甲醇酯與間苯二甲酸-1，4-環己烷二甲醇醋之 共聚合物之太陽能電池模組用保護片。此種太陽能電池模 組用保護片，係優於耐水解性、而能耐太陽能電池模組的 長時間使用。太陽能電池模組用保護片，特佳爲作爲太陽 能電池模組用背面保護片使用。 本發明提供一種太陽能電池模組，其特徵爲：具備含 有太陽能電池元件之塡充層、及經配置於前述塡充層表面 之表面保護片、以及經配置於前述塡充層背面之背面保護 片，而表面保護片及背面保護片的至少一邊’具有上述之 任一對苯二甲酸-1，4-環己烷二甲醇酯與間苯二甲酸-1，4-環己烷二甲醇酯之共聚合物薄膜。 [發明之效果] 201221544 如採用本發明，則可提供優於耐水解性之薄膜、太陽 能電池模組用保護片、以及太陽能電池用模組》 [發明之最佳實施形態] 以下，就本發明之最佳實施形態，加以詳細說明。本 發明，並不因下述之實施形態而有所限定。 本實施形態之對苯二甲酸-1,4-環己烷二甲醇酯與間苯 二甲酸-1,4-環己烷二甲醇酯之共聚合物薄膜，係由含有對 苯二甲酸- I，4-環己烷二甲醇酯與間苯二甲酸- ：!，4_環己烷 二甲醇酯之共聚合物（以下，稱爲「共聚合物A」）之樹脂 組成物所成者。 對苯二甲酸酯與間苯二甲酸酯的莫耳比，並不特別加 以限定，惟通常爲99.9: 0.1至50: 50、較佳爲99: 1至 7〇 : 30程度。又，共聚合物 A的固有黏度（IV値 (intrinsic viscosity value)，較佳爲 0.5 至 l.Odl(分升）/g、 更佳爲0.75至l.〇dl/g。IV値係如下述方式求出》亦即， 對苯酚60質量％與1，1，2,2·四氯化乙烯40質量％的混合溶 劑中’按能成爲0.5g/100ml之濃度的方式使共聚合物A 溶解。採用毛細管黏度計（capillary viscosimeter)，在25 °C下’測定溶液在毛細管黏度計中的落下時間，將此設爲 ts。又，測定僅溶劑時的毛細管黏度計中的落下時間，將 此設爲to。依IV値=[ln(ts/to)]/0.5的計算式，則可求得 IV値。在此，「in」表示自然對數（naturai i〇garithm)的 基數（base)。 -8 - 201221544 於含有共聚合物A之樹脂組成物中之共聚合物A @ 含有比例，係從增高耐水解性的觀點來看，較佳爲5 〇至 1〇〇質量％、更佳爲60至100質量％、再佳爲70至100 質量％。 含有共聚合物A之樹脂組成物，亦可適當含有共聚 合物A以外之有機物、無機物以及各種添加劑。共聚合 物A以外的有機物而言，可例舉：環狀或線狀的共聚物A 低聚物（oligomer)、構成共聚合物A之酸成分或乙二醇 (glycol)成分的單體（m〇nomer)及源自此等之低分子量反應 物、共聚合物A以外的樹脂、以及各種添加劑。共聚合 物A以外的樹脂而言，可例舉：聚對苯二甲酸乙二醇酯 (PET)、聚對苯二甲酸丁二醇酯（PBT)、聚萘二甲酸乙二醇 酯（PEN)、聚萘二甲酸丙二醇酯、聚萘二甲酸丁二醇酯等 的熱塑性聚酯、熱固性聚酯、耐綸（Nylon)6、耐綸66、耐 綸11、耐綸12等的熱塑性聚醯胺 '聚碳酸酯、聚縮醛、 聚苯乙烯、ABS(丙烯腈-丁二烯-苯乙烯三元共聚合物）樹 脂、聚胺基甲酸乙酯、含氟樹脂、聚矽氧樹脂（silicone resin)、聚伸苯基硫醚樹脂、纖維素、聚伸苯基醚樹脂 等、以及此等的共聚合樹脂等。 無機物而言，可例舉：玻璃纖維、碳纖維、滑石、雲 母、矽灰石（wollastonite)、高嶺黏土、層狀矽酸鹽、碳酸 鈣、二氧化鈦、二氧化矽等的無機塡充劑或無機滑劑 (inorganic synovial agent)、聚合觸媒殘渣等- 又’添加劑而言，可例舉：有機或無機的染料或顔 _ 9 - 201221544 料、消光劑（flatting agent)、熱安定劑（thermal stabilizer)、阻燃劑、防靜電劑（antistatic agent)、消泡劑 (deforming agent)、整色劑（ortho chromatic agent)、抗氧 化劑、紫外線吸收劑（ultraviolet ray absorbing agent)、結 晶造核劑（crystal nucleus growing agent)、增白劑 (whitening agent)、潤滑劑（lubrieant)、不純物的捕獲劑 (scavenging agent)、增稠劑（thickner)、表面調整劑 (surface regulator)等。此中，含有熱安定劑、或低分子量 的揮發性不純物的捕獲劑爲宜。作爲熱安定劑、較佳爲5 元及/或3元的磷化合物或受阻酚（hindered phenol)系化合 物等，作爲低分子量的揮發性不純物的捕獲劑而言，較佳 爲聚醯胺或聚酯型醯胺的聚合物或低聚物、具有醯胺基或 胺基之低分子量化合物。 本實施形態的共聚合物A薄膜，係依DMA法所測定 之玻璃化溫度在1 30°C以上者。依DMA法所測定之玻璃 化溫度’較佳爲1 4 0 °C以上、更佳爲1 5 0 °C以上。依D Μ A 法所測定之玻璃化溫度的上限並不特別加以限定，惟通常 爲200°C以下，較佳爲180°C以下、更佳爲170°C以下、 再佳爲160°C以下。 DM A法係如下述之方法。亦即，從室溫按5 °C /分鐘 之方式使試片升溫、並使用黏彈性測定裝置以測定試片的 動態黏彈性（dynamic viscoelasticity)及損失正切角（loss tangent angle)，從損失正切角的峰値溫度即可求得玻璃化 溫度。在此’測定頻率則作成1 Hz(赫茲）。 201221544 又’本實施形態的共聚合物A薄膜，係依TMA法所 測定之玻璃化溫度在200t以上者。依ΤΜΑ法所測定之 玻璃化溫度’較佳爲210°C以上、更佳爲220。(：以上、再 佳爲23 0°C以上、特佳爲23 5 °C以上者。依TMA法所測定 之玻璃化溫度的上限並不加以限定，惟通常爲260 t以 下、較佳爲2 5 5 °C以下、更佳爲2 5 0 t以下、再佳爲2 4 5 °C以下。 Τ Μ A法係如下述之方法。亦即，從室溫按丨〇它/分鐘 之方式使試片升溫、並使有熱分析裝置以測定厚度方向的 熱膨脹量’以製圖能表示溫度與熱膨脹量的關係之圖表。 並於玻璃轉化點前後的曲線劃正切線（tangent line)，從該 正切線的交點，即可求得玻璃化溫度。 又’本實施形態之共聚合物A薄膜，係於X射線繞 射中’在22°$20 S24。的範圍具有最大峰値》 本實施形態之共聚合物A薄膜，係耐水解性優異 者。爲何有關本實施形態之共聚合物A薄膜能具有此種 特性之原理尙未明瞭，惟作爲其要因，可舉出下列事實。 關於上述之玻璃化溫度、及最大峰値之特性，係與本 實施形態之共聚合物A薄膜中的共聚合物A經某種程度 以上結晶化之事實有關連。並且，可能由於共聚合物A 經某種程度以上（以結晶化度計，較佳爲20%以上、更佳 爲3 0%以上）結晶化之事實而耐水解性增高者。 本實施形態之共聚合物A薄膜的斷裂強度（breaking strength)，係於根據 JIS-K7127之測定中，MD(縱向）方 -11 - 201221544 向.TD(橫向）方向，均較佳爲80MPa(兆帕）以上、更佳爲 90MPa以上、更佳爲l〇〇MPa以上。 本實施形態之共聚合物A薄膜的斷裂延性（breaking ductility)，係於根據JIS-K7127之測定中，MD方向· TD 方向，均較佳爲150MPa以下、更佳爲120MPa以下、再 佳爲80MPa以下。 本實施形態之絕緣擊穿電壓（dielectric breakdown voltage)，係於根據 ASTM D-149之測定中，較佳爲 90kV/mm 以上、更佳爲 1 1 Ok V/mm 以上、再佳爲 1 3 Ok V/mm 以上。 本實施形態之熱膨脹係數（CTE(co efficient of thermal expansion))，係於依TMA法（50至100°C)之測定中，MD 方向，TD方向，均較佳爲80ppm/°C以下、更佳爲60ppm/ °C以下、再佳爲40PPm/°C以下。 本實施形態之共聚合物A薄膜的厚度，可視太陽能 電池模組用背面保護片的厚度及所要求之性能而適當加以 選擇，惟較佳爲 ΙΟμηι至 500μιη、更佳爲 20μηι至 300μηι、再佳爲30μηι至200μιη。如作成此種範圍，則薄 膜之製造成爲容易之同時，因強度·剛性增高而操作處理 性或後加工性會成爲容易。厚度偏差較佳爲±10%以內， 更佳爲±7%以內，再佳爲±5%以內。 有關本實施形態之共聚合物Α薄膜，可依下述之方 式製造。 首先，準備將成爲原料之共聚合物A樹脂（例如，顆 -12- 201221544 粒（pellet))。共聚合物A樹脂，依周知的方法進行丨，4-環 己烷二甲醇、對苯二甲酸、以及間苯二甲酸之聚縮合 (polycondensation) ’即可製造。又，共聚合物 a顆粒， 亦從伊斯特受（Eastman)社，例如，以商品名「Eastman Copolyester(伊斯特曼共聚酯）13319」等在市售。 然後，將共聚合物A樹脂由加熱而熔融，需要時添加 添加劑’以製得含有共聚合物A之樹脂組成物。然後， 將此樹脂組成物成型爲薄膜。成型爲薄膜之方法而言，可 例舉：將含有共聚合物A之樹脂組成物，在熔融狀態 下’從口模頭（die)擠出以成型之熔融成型（molten moulding)法、將經將樹脂組成物溶解於溶劑中之溶液塗 佈於支撐體上，然後使溶劑乾燥之溶液流涎（solution casting)法等。此等之中，最佳爲生產性、環境適合性 (environment aptitude)優異、一過程即可製得薄膜之熔融 成型法。熔融成型法而言，較佳爲採用T型模頭（T-die)、 或I型模頭（I-die)之方式、或水冷式及氣冷式的薄膜吹塑 (inflation filming)方法。 接著，進行所成型之未延伸之共聚合物A薄膜之延 伸（drawing)，即可製得有關本實施形態之上述共聚合物a 薄膜。 延伸條件或延伸方法並不特別加以限定，可在能獲得 上述之玻璃化溫度之範圍或於X射線繞射中之既定的角 度範圍內可獲得最大峰値之範圍內適當加以調整。 例如，延伸方向，可爲單軸或雙軸，惟較佳爲雙軸。 -13- 201221544 延伸方法亦並不特別加以限定，可將輥式延伸（r〇n drawing)、拉幅式延伸（tenter drawing)等的種種方法，按 單獨方式或任意組合後使用。 延伸倍率（e 1 ο n g a t i ο n r a t i 〇)亦並不特別加以限定。例 如，可作成往MD(machine direction (縱向））方向2倍至5 倍、往 TD(transverse direction(橫向））2 倍至 5 倍之方 式。 將本發明之太陽能電池模組用背面保護片（以下，簡 稱「背面保護片」）的構成的一實施例，表示於第1圖 中。背面保護片1，在氣體阻障性（gas barrier)薄膜20兩 面，具有層壓具有耐熱性之薄膜基材3 0，32所成之構 成。氣體阻障性薄膜20，係經於基材10片面設置由無機 化合物所成之蒸鍍層12者。作爲基材10，可使用上述的 共聚合物A薄膜。 於本實施形態中所用之具有耐熱性之薄膜基材30，32 而言，抵要是具有耐熱性者即可，可例舉：聚對苯二甲酸 乙二醇酯（PET)薄膜或者選自聚氟化乙烯樹脂（PVF)薄膜、 聚氟化亞乙烯樹脂（PVDF)薄膜、聚三氟化氯化乙烯樹脂 (PCTFE)薄膜、乙烯-四氟化乙烯共聚合物（ETFE)薄膜、聚 四氟乙烯（PTFE)薄膜 '四氟化乙烯-全氟烷基乙烯醚共聚 合物（PFA)薄膜之含氟系基材。又，作爲具有耐熱性之薄 膜基材3 0, 32，共聚合物A薄膜亦很適合使用。 薄膜基材30，32的厚度並不特別加以限定，例如， 較佳爲作成3至200μιη、更佳爲作成6至30μηι。 -14- 201221544 蒸鍍層1 2的材料亦並不特別加以限定，可例舉：氧 化鋁、氧化矽、氧化錫、氧化鎂、氧化鋅，此等的2種以 上的混合物。蒸鍍層12的厚度並不特別加以限定，例 如，較佳爲5至3 00nm、更佳爲1 〇至1 5〇nm。 進行本實施形態的氣體阻障性薄膜20與有耐熱性之 薄膜基材3 0，32之層壓之方法而言，例如，可採用將氣 體阻障性薄膜20與具有耐熱性之薄膜基材30，32，需要 時介由膠黏劑（tackifier)而貼合之乾式層壓（dry lamination) 之層壓方式以進行層壓。乾式層壓用膠黏劑而言，必須爲 不會發生膠黏強度用長期間的層外使用而劣化所致之分層 (delamination)等、再者，膠黏劑不會黃變（yellowing) 等，爲對應高耐熱性、抗濕熱性（wet and heat resistance) 等起見，較佳爲使用作爲構成膠黏劑的媒液（vehicle)之成 分的樹脂等，能在進行交聯並硬化後形三維篩網（three-dimensional mesh)狀的交 聯構造 （cross-linking structure) 者。具體而言，構成上述的層壓用膠黏劑層之膠黏劑，較 佳爲在硬化劑或交聯劑的存在下，能因由熱或光線等所成 之反應能量而形成交聯構造。例如在二液硬化型（two-fluid hardening type)聚胺基 甲酸乙 酯系膠 黏劑等 脂肪族 系•脂環系異氰酸酯、或者，芳香族系異氰酸酯等的異氰 酸酯系的硬化劑或交聯劑的存在下，因由熱、或光線所成 之反應能量而層壓用膠黏劑形成交聯構造之結果，能製造 耐熱性、耐氣候性、抗濕熱性等優異的太陽能電池模組用 背面保護片。 -15- 201221544 於上述膠黏劑中，脂肪族系異氰酸酯而言，例如，可 使用1，6-伸己基二異氰酸酯（HDI)、脂環系異氰酸酯而 言，例如，可使用異佛爾酮二異氰酸酯（IPDI)、芳香族系 異氤酸酯而言，例如，可使用伸甲苯二異氰酸酯（TDI)、 二苯基甲烷二異氰酸酯（MDI)、萘二異氰酸酯（NDI)、二甲 基聯苯二異氰酸酯（TODI)、伸苯二甲基二異氰酸酯（XDI) 等。 再者，上述膠黏劑中，爲防止紫外線變質（ultraviolet ray deterioration)等起見，可添加紫外線吸收劑或者光安 定劑（optical stabilizer)。其使用量而言，雖因其粒子形 狀、密度等而有所不同，惟較佳爲約0.1至10重量％程 度。 上述膠黏劑，例如，可利用：輥式塗佈法（roll coating)、凹輥塗佈法（gravure coating)、輕紙塗佈法（kiss roll coating)、其他的塗佈法、或印刷法（printing)等實 施，而其塗佈量而言，約爲2至20g/m2 (乾燥狀態）程度、 較佳爲3至10g/m2(乾燥狀態）的範圍爲宜》 又，於上述構成中，就具有耐熱性之薄膜基材3 0，32 而表示將預先經成型爲薄膜狀之樹脂層壓於氣體阻障性薄 膜20上之狀態，惟亦可不採用此種狀態，而作成將含有 具有耐熱性之塗工液塗佈於氣體阻障性薄膜20，需要時 進行乾燥之結果形成經層壓於氣體阻障性薄膜20上之薄 膜基材30，32之狀態。塗佈之方法而言，可適用：輥式 塗佈法、凹輥塗佈法、輥舐塗佈法、其他的塗佈法、或印 -16- 201221544 刷法等。其塗佈量而言，硬化後的塗工膜的厚度能成爲1 至ΙΟΟμιη (乾燥狀態）、較佳爲5至50μιη (乾燥狀態）之範圍 爲宜。 由於如此方式所製得之本發明之太陽能電池模組用背 面保護片，具有上述的共聚合物Α薄膜之故，特別優於 耐水解性。因而，如此之太陽能電池用背面保護片，係能 長期間保護太陽能電池、且廉價者。 再者，太陽能電池模組用背面保護片的構成，並不限 定於上述之構成。 例如，於蒸鍍層1 2與基材1 0之間，爲提高此等之間 的密貼性起見，亦可設置透明底漆層（transparent primer layer)。透明底漆層的樹脂而言，可例舉：有機矽烷偶合 劑（silane coupling agent)或其水解物、與多元醇（polyols) 及異氰酸酯化合物的複合物（complex)。 有機矽烷偶合劑而言，例如可採用：乙基三甲氧矽 烷、乙烯基三甲氧矽烷、r-氯化丙基甲基二甲氧矽烷、 r-氯化丙基三甲氧矽烷、縮水甘油氧丙基三甲氧矽烷、 r-甲基丙烯氧丙基三甲氧矽烷、r-甲基丙烯氧丙基甲基 二甲氧矽烷等的有機矽烷偶合劑或其水解物的1種或2種 以上。又，有例如含有如r-異氰酸酯丙基三乙氧矽烷、 r-異氰酸酯丙基三甲氧矽烷般之異氰酸酯基者、含有如 r-锍基丙基三乙氧矽烷般之锍基者，或含有如r-胺基丙 基三乙氧矽烷、r -胺基丙基三甲氧矽烷、N-沒-(胺基甲 基）-r-胺基丙基三乙氧矽烷、r-苯基胺基丙基三甲氧矽 -17- 201221544 烷般的胺基者。再者，含有如r-縮水甘油氧丙基三甲氧 矽烷或yS -(3，4-環氧環己基）乙基三甲氧矽烷等般的環氧基 者、或如乙烯基三甲氧矽烷、乙烯基（Θ -甲氧乙氧）矽烷 等般之有機矽烷偶合劑中加成醇等並加成羥基等者亦可， 可採用此等的1種或2種以上。 多元醇而言，例如，使乙基甲基丙烯酸酯、羥基乙基 甲基丙烯酸酯或羥基丙基甲基丙烯酸酯、羥基丁基甲基丙 烯酸酯等的丙烯酸衍生物單體按單獨方式聚合者，或添加 苯乙烯等的其他單體後使其共聚合之丙烯基多元醇等很適 合使用。 異氰酸酯化合物而言，例如可使用：芳香族系的伸甲 苯二異氰酸酯（TDI)或二苯基甲烷二異氰酸酯（MDI)、脂肪 族系的伸苯二甲基二異氰酸酯（XDI)或六伸甲基二異氰酸 酯（HMD I)等的單體與此等的聚合物或衍生物，而可使用 此等的1種或2種以上》 透明底漆層的厚度並不特別加以限制，惟較佳爲 0.001 至 2μηι、更佳爲 〇.〇3 至 0·5μηιο 又’亦可於蒸鍍層12與薄膜基材32之間，再設置具 有氣體阻障性之保護膜層（overcoat layer)。保護膜層，例 如’含有水溶性高分子，及一種以上的烷氧基金屬 (alkoxide)或其水解物，並將以水或水•醇混合物作爲溶 媒之塗佈液，塗佈於蒸鍍層12上即可形成。 水溶性高分子而言，可例舉：聚乙烯醇、聚乙烯基吡 咯烷酮、澱粉、甲基纖維素、羧基甲基纖維素、褐藻酸鈉 -18- 201221544 (sodium alginate)等 ° 烷氧基金屬而言，可例舉：四乙氧矽烷、三異丙氧鈉 等。 又’亦可將蒸鍍層12形成於基材10兩面。在此情 形’亦可對雙方的蒸鍍面，形成上述透明底漆層或保護 層。 又，例如，如將太陽能電池模組用背面保護片適用於 氣體阻障性的需要性低的太陽能電池模組時，則可將該太 陽能電池模組用背面保護片作成不具有蒸鍍層1 2之狀 態。在此情形，則在基材1 〇的單面或兩面形成具有耐熱 性之薄膜基材3 0，3 2。 又，太陽能電池模組用背面保護片1，亦可不具有薄 膜基材3 0，32的任一或者兩者，再者，亦可爲僅由上述 基材1 0所構成。 接著，就經使用本發明之太陽能電池用背面保護片之 太陽能電池模組加以說明。第2圖係就具備有本發明之太 陽能電池用背面保護片之太陽能電池模組1 00，表示其一 實施之槪略剖面圖。 本實施形態之太陽能電池模組100，係作成於太陽能 電池模組1 〇〇的背面側塡充材層5 3側配置有：太陽能電 池模組用表面保護片60、表面側塡充材層5 1、配設有配 線52之作爲光電動勢元件（photoelectromotive element)的 太陽能電池元件50、背面側塡充材層53，以及，上述背 面保護片1的具有上述耐水解性之薄膜基材30之構成。 -19- 201221544 對此等的各構件，利用例如，藉由真空吸引（vacuume suction)等而加以—體化後加熱壓延（heating calendering) 之層壓（lamination)法等的成型法，即可將上述各層作爲 —體成型物進行加熱壓延成型。再者，太陽能電池模組 1 〇〇 ’亦可安裝例如鋁製的框體（未圖示）。 構成上述太陽能電池模組之通常的太陽能電池模組用 表面保護片60而言，從具有太陽光的穿透性、絕緣性 等’再具有耐氣候性、耐熱性、耐光性、耐水性、防濕 性、防污性、其他各種特性、優於物理性或化學性強度 性、強韌性等，並富於極佳的耐久性，再者，作爲光電動 勢元件的太陽能電池元件的保護來看，需要爲優於耐刮痕 性、衝擊吸收性等者。 具體而言，可使用周知的玻璃板等，再者，可使用例 如，聚醯胺系樹脂（各種耐綸）、聚酯系樹脂、環狀聚烯烴 系樹脂、聚苯乙烯系樹脂、（甲基）丙烯酸系樹脂、聚碳酸 酯系樹脂、縮醛系樹脂，其他各種樹脂薄膜或片材，再 者，共聚合物A亦很適合使用。上述樹脂的薄膜或者片 材而言，可使用經雙軸定向拉伸（biaxial orientation)之延 伸薄膜（stretched film)或片材。又，該樹脂的薄膜或片材 的厚度而言，祗要是爲保持強度、剛性、彈性復原強度 (nerve)等所需要之最低限的厚度即可，如過厚時亦有成本 上升的缺點，如過薄時則強度、剛性、強性復原強度等會 降低之故不宜。本實施形態中，由於如上述般之理由，樹 脂的薄膜或片材的厚度，較佳爲12至200 μιη、更佳爲 -20 - 201221544 25μηι 至 150μπι。 將層壓於構成太陽能電池模組之太陽能電池模組用表 面保護片60之下之塡充材層5丨而言，由於介由表面保護 片60而太陽光將入射，並將此穿透後吸收之故需要具有 透明性’又，亦需要具有表面保護片與背面保護片之間的 膠黏性。又’從能發揮保持作爲光電動勢元件的太陽能電 池元件表面的平滑性之功能而具有熱塑性，再者，爲保護 作爲光電動勢元件的太陽能電池元件之觀點來看，需要優 於抗刮痕性、衝擊吸收性等。 具體而言，作爲上述塡充劑層，例如，可使用：乙 稀-醋酸乙稀共聚合物、離子鍵聚合物（ionomer)樹脂、乙 烯-丙烯酸，或者’酸改性聚烯烴系樹脂、聚乙烯醇縮丁 醛樹脂、矽酮系樹脂、環氧系樹脂、（甲基）丙烯酸系樹 脂、其他樹脂的1種或2種以上的混合物。於本實施形態 中’於構成上述塡充材層之樹脂中，爲提升耐熱性、耐光 性、耐水性等的耐氣候性等起見，在不影響其透明性之範 圍內，可任意添加例如，交聯劑、熱氧化防止劑、光安定 劑、紫外線吸收劑、光氧化防止劑、其他種添加劑、並混 合者。再者’本實施形態中，太陽光的入射側的塡充劑而 言’如考慮耐光性、耐熱性、耐水性等的耐氣候性等的性 能方面與價格方面時，則乙烯-醋酸乙烯系樹脂爲很合適 的素材。在此，上述塡充材層的厚度而言，較佳爲200至 ΙΟΟΟμηι、更佳爲 350 至 600μηι。 作爲構成太陽能電池模組之光電動勢元件的太陽能電 -21 - 201221544 池元件5 0而言’可使用在來周知者，例如，單晶體矽型 太陽能電池元件、多晶體矽型太陽能電池元件等的晶體矽 太陽能電子元件，由單接合（single junction)型、串聯式 構造（tandem structure)型等所成之非晶形矽（ani〇rph〇us silicon)太陽能電池元件、砷化鎵（GaAs)或磷化銦（InP)等 的III-V族化合物半導體太陽能電池元件、碲化鎬（cdTe) 或銅銦硒化物（CulnSe2)等的II-VI族化合物半導體太陽能 電池元件、有機太陽能電池元件、其他等。再者，亦可使 用：薄膜多晶體性矽太陽能電池元件、薄膜微晶性矽太陽 能電池元件、薄膜晶體太陽能電池元件與非晶矽太陽能電 池兀件的混雜種兀件（hybrid element)等。 將層壓於構成上述太陽能電池模組之光電動勢元件之 下之背面側塡充材層53而言，可使用與將層壓於上述太 陽能電池模組用表面保護片之下之表面側塡充材層5 1同 樣材質者。亦需要具有與背面保護片之間的膠黏性，從爲 能發揮保持作爲光電動勢元件的太陽能電池元件的背面的 平滑性之功能而具有熱塑性、再者，爲保護作爲光電動勢 元件的太陽能電池元件之觀點來看，需要優於抗刮痕性、 衝擊吸收性等。 如採用上述的本發明之太陽能電池模組，則由於爲上 述的背面保護片及表面保護片的至少一邊使用有上述共聚 合物A薄膜之故，背面保護片或表面保護片的耐水解性 較高。因而’與使用有在來的聚對苯二甲酸乙二醇酯（PET) 薄膜或聚萘二甲酸乙二醇酯（PEN)薄膜之情形比較時，更 -22- 201221544 能長期維持作爲太陽能電池的電力輸出特性。 再者，太陽能電池模組亦不因上述構成而有所限定， 而能作成種種構成。例如，作爲背面保護片1，可採用如 上述般的種種構成》簡言之，祗要是具備有：包含有太陽 能電池元件50之塡充層、及經配置於該塡充層表面之表 面保護片60、以及經配置於塡充層背面之背面保護片1， 而表面保護片60及背面保護片1的至少一邊係包含有上 述共聚合物A薄膜者即可。 【實施方式】 [實施例] 以下’將舉出實施例及比較例，藉以更具體方式說明 本發明內容。在此，本發明並不因下述實施例而有所限 定。 作爲薄膜的原料’使用下列樹脂顆粒。在此，PEN係 聚萘二甲酸乙二醇酯。 (1) 共水口物A(伊斯特曼社製' 商品名·· Eastman Copolyester 13319) (2) PEN(帝人杜邦薄膜社製、商品名：鐵歐尼克斯 Q51) (3) 1,4-環己烷二甲醇· 2,2,4,4_四甲基-丨，3•環丁烷二 醇•對酞酸聚縮合物（伊斯特曼社製、商品名：Eastman TriunCoP〇lyesterFX200)(以下，簡稱「共聚合物b」） -23- 201221544 [實施例i] 藉由共聚合物A(顆粒狀）之熔融擠出而使其薄膜化， 並再進行雙軸定向拉伸’以製得厚度50μιη的延伸共聚合 物Α薄膜。 [實施例2] 改變延伸比例（elongation rate)以將厚度作成ΙΟΟμπι 以外，其餘則按與實施例1同樣方式，以製得厚度1 00μm 的共聚合物A薄膜。 [比較例1] 藉由PEN(顆粒狀）之熔融擠出而使其薄膜化，並再進 行雙軸定向拉伸，以製得厚度25 μηι的延伸PEN薄膜。 [比較例2] 藉由共聚合物A(顆粒狀）之熔融擠出而使其薄膜化， 以製得厚度ΙΙΟμηι的未延伸共聚合物A薄膜。 [比較例3] 藉由共聚合物B(顆粒狀）之熔融擠出而使其薄膜化， 以製得厚度100 μιη的未延伸共聚合物B薄膜。 <各種物性〉 就實施例1及2以及比較例1至3的薄膜，測定斷裂 • 24- 201221544 強度、斷裂延性、玻璃化溫度、熔點、絕緣擊穿電壓、比 重以及熱膨脹係數。將各測定之測定方法及測定値，表示 於表I中。 [表1] 薄膜_膜厚 共聚尚 邮延伸 PEN延伸 共聚飾A 未延伸 共聚合物Β 未延伸 50 μ m t〇〇ii m 25/1 m 110μτη 100 μ π 項目 測定方法 實施例1 實施例2 比較例1 比較例2 比較例3 斷裂強度(MPa) MO 120 100 180 50 50 TD too 100 200 50 50 MO 50 80 30 200 120 (70) TD 60 80 20 210 120 玻璃化溫度(它） DMA 155 165 112 141 TMA 240 240 98 121 熔點(°c) DSC 285 269 285 - 释緣擊穿電壓 (kV/mm) ASTM D-149 1B0 130 200 80 110 比重 ASTM D-792 1.24 1.3G 1.195 1.17 熱膨脹係數 MD 29 37 1 138 109 [50-100*0] (ppm/t) TO 39 38 4 114 98 <水解性試驗> 就實施例1及2以及比較例1至3的薄膜’實施壓力 鍋試驗（1 20°C、1 〇〇%RH(相對濕度）、2大氣壓）。就各薄 膜，測定50小時後、1 〇〇小時後、1 5〇小時後以及200小 時後的抗張強度保持率及拉伸延伸保持率。將其結果’表 示於第3圖及第4圖中。實施例1及2的薄膜’係較比較 例1至3的薄膜其抗張強度保持率及拉伸延伸保持率的低 落爲緩慢。 <結晶度（crystaUinity)之測定〉 -25- 201221544 就實施例1、實施例2、以及比較例2的薄膜，實施 使用Cuk 〇:線之粉末X射線繞射（powder X-ray diffraction)，以進行繞射特性曲線（diffracti0I1 pattern)的 確認及結晶度的算出。測定方法及測定條件，爲如下所 述。靶材（target) : Cu(銅）、X-射線管電流：40mA、X射 線管電壓：45kV、掃描範圍（scan width): 20 =4至65。、 步驟（step) : 2 0 =0.01 671。、平均時間/步驟： 10.160s(秒）' 固定發射夾縫（fixed divergent slit): 1/2。、 旋轉速度：每分鐘60旋轉、結晶度解析（crytaHinity analysis):哈曼斯（Harmans)法、前處理：無。 將X射線的入射方向與反射方向所成角度2 0與繞射 強度（diffraction strength)之間的關係，表示於第 5圖 中。於實施例1、2的薄膜中，在22°$20 $24°的範圍內 確認有明確的尖銳的最大峰値，惟於比較例2的薄膜中則 並未能確認尖銳的峰値的存在，因而獲知其係屬於非晶形 者。又，根據第5圖，以求出實施例1及實施例2的薄膜 之結晶度之結果，各爲4 2.8 %、3 9.7 %。 又，於實施例1、2中，第二強的峰値，出現於20 =16至17°、第三強的峰値則出現於2 0 =19至20°。峰値 強度比，爲第二強的峰値/最大峰値=〇·1至0.2程度。 【圖式簡單說明】 第1圖：係本發明之一實施形態的太陽能電池模組用 背面保護片的剖面圖。 -26- 201221544 第2圖：係本發明之一實施形態的太陽能電池模組的 槪略剖面圖。 第3圖：就實施例1，2及比較例1至3的薄膜，表示 於壓力鍋（pressure cooker)試驗中之抗張強度（tensile strength)保持率的經時變化之圖表。 第4圖：就實施例1，2及比較例1至3的薄膜，表示 於壓力鍋試驗中之拉伸延伸（tensile ductility)保持率的經 時變化之圖表。 第5圖：表示實施例1，2及比較例2的薄膜的X射線 繞射結果之圖。 【主要元件符號說明】 1 :太陽能電池模組用背面保護片 1 0 :基材 1 2 :蒸鎞層 20 :氣體阻障性薄膜 3 0,32 :薄膜基材 5〇 :太陽能電池元件 5 1 :表面側塡充材層 52 :配線 5 3 :背面側塡充材層 6〇 :太陽能電池模組用表面保護片 100 :太陽能電池模組 -27-201221544 VI. Technical Field of the Invention [Technical Field of the Invention] The present invention relates to a copolymer of terephthalic acid-1,4-cyclohexanedimethanol ester and isophthalic acid-1,4-cyclohexanedimethanol ester. A protective film for a film, a solar cell module, and a solar cell module. [Prior Art] As a clean energy source for replacing fossil fuels, solar cell power generation systems are being expected. In general, in a solar cell power generation system, a solar cell module in which a plurality of components of a plurality of solar cell elements are connected in series or in parallel is protected by various components. In general, a solar cell module is designed such that a surface directly irradiated with sunlight is covered by a white board reinforced glass, and a solar cell element group is disposed under the surface, and a transparent ethylidene group is used. A structure in which a gap such as a base acetate resin or the like is buried in the gap and the back surface is protected by a weather resistant plastic material (for example, Patent Documents 1 and 2). Since the solar cell module is used outdoors, it is required to have sufficient durability and weather resistance in terms of its structure, material structure, and the like. Specially, it is a protective sheet for solar cell modules (especially a back protective sheet). • It needs to have weather resistance, especially hydrolysis resistance. This is because the protective sheet is decomposed and peeled off by the moisture such as rain during long-term use outside the house, and thus the exposed wiring is corroded and the output of the module may be affected. [Prior Art Document] -5-201221544 [Patent Document 1] Patent Document 1: JP-A-2000-243999 (Patent Document 2) Japanese Patent Laid-Open Publication No. JP-A No. 2008-23-5603 As a substrate for a back surface protective sheet for a solar cell module, there are various types of thin film materials, but a film material having good hydrolysis resistance has not been developed. For example, a polyethylene terephthalate (PET) film or a polyethylene naphthalate (PEN) film is insufficient in hydrolysis resistance, and is unsuitable as a substrate for a back surface protective sheet for a solar cell film group. Practical. Thus, the object of the present invention is to provide a film excellent in hydrolysis resistance, a protective sheet for a solar cell module using the film, and a solar cell film group. [Means for Solving the Problem] As a result of intensive research by the present inventors, it was found that specific terephthalic acid-1,4-cyclohexanedimethanol ester and isophthalic acid-1,4·cyclohexanedimethanol. The ester copolymer film is excellent in hydrolysis resistance and is suitable for the substrate of a protective sheet for a solar cell module, and the present invention has been completed. The present invention provides a terephthalic acid-1,4-cyclohexanedimethanol ester and an isophthalic acid-1,4- measured by a DMA (viscoelasticity measuring device) method having a glass transition temperature of 130 ° C or higher. A copolymer film of cyclohexanedimethanol ester. • 6 - 201221544 Further, the present invention provides a 1,4-cyclohexanyl dimethanol terephthalate and isophthalic acid-1 having a glass transition temperature of 200 C or more as measured by the TMA (heat engine analyzer) method. , 4-cycloheximide dimethanol ester copolymer film. Further, the present invention provides a terephthalic acid terpolymer of terephthalic acid having a maximum peak in the range of 22°S20S24° in X-ray diffraction (x_ray diffracti〇n)_ a copolymer film of 1,4_cyclohexane dimethanol vinegar. These copolymer films of terpene terephthalate-1,4-cycloheximide dimethanol ester and isophthalic acid _1.4-cyclohexanedimethanol ester are excellent in hydrolyzability. The invention provides a solar cell module comprising at least one layer of any of the above-mentioned copolymers of p-benzoic acid-1,4-cyclohexanedimethanol ester and isophthalic acid-1,4-cyclohexane dimethanol vinegar. Use a protective sheet. The protective sheet for such a solar cell module is superior to hydrolysis resistance and can withstand long-term use of the solar cell module. A protective sheet for a solar cell module is particularly preferably used as a back protective sheet for a solar cell module. The present invention provides a solar cell module comprising: a buffer layer including a solar cell element; and a surface protection sheet disposed on a surface of the buffer layer; and a back surface protection sheet disposed on a back surface of the buffer layer And at least one side of the surface protective sheet and the back protective sheet has any of the above-mentioned -1,4-cyclohexanedimethanol terephthalate and -1,4-cyclohexanedimethanol isophthalate Copolymer film. [Effects of the Invention] According to the present invention, a film superior to hydrolysis resistance, a protective sheet for a solar cell module, and a module for a solar cell can be provided. [Best Embodiment of the Invention] Hereinafter, the present invention The best embodiment will be described in detail. The present invention is not limited by the following embodiments. The copolymer film of terephthalic acid-1,4-cyclohexanedimethanol ester and isophthalic acid-1,4-cyclohexanedimethanol ester of the present embodiment is composed of terephthalic acid-containing I A resin composition of a copolymer of 4-cyclohexanedimethanol ester and isophthalic acid-:-, 4-cyclohexanedimethanol ester (hereinafter referred to as "copolymer A"). The molar ratio of terephthalate to isophthalate is not particularly limited, but is usually from 99.9: 0.1 to 50: 50, preferably from 99: 1 to 7: 30. Further, the intrinsic viscosity (IVintinic viscosity value of the copolymer A is preferably from 0.5 to 1.0 dl (dl) / g, more preferably from 0.75 to 1. 〇 dl / g. The IV 値 is as follows In the mixed solvent of 60% by mass of phenol and 40% by mass of 1,1,2,2·tetrachloroethylene, the copolymer A is dissolved in a concentration of 0.5 g/100 ml. Using a capillary viscosimeter, the drop time of the solution in the capillary viscometer was measured at 25 ° C, and this was set to ts. Further, the drop time in the capillary viscometer when only the solvent was measured was determined. Set to to. According to the calculation formula of IV値=[ln(ts/to)]/0.5, IV値 can be obtained. Here, “in” represents the base of the natural logarithm (naturai i〇garithm). -8 - 201221544 The copolymer A @ content ratio in the resin composition containing the copolymer A is preferably from 5 Å to 1% by mass, more preferably from the viewpoint of increasing hydrolysis resistance. 60 to 100% by mass, more preferably 70 to 100% by mass. The resin composition containing the copolymer A may also contain the copolymer A as appropriate. Other than the organic substance, the inorganic substance, and various additives. The organic substance other than the copolymer A may, for example, be a cyclic or linear copolymer A oligomer, an acid component constituting the copolymer A or ethylene. A monomer (m〇nomer) of a glycol component, a low molecular weight reactant derived therefrom, a resin other than the copolymer A, and various additives. Examples of the resin other than the copolymer A include: Polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene naphthalate (PEN), polybutylene naphthalate, polybutylene naphthalate Thermoplastic polyester such as thermoplastic polyester, thermosetting polyester, Nylon 6, nylon 66, nylon 11, nylon 12, etc., polycarbonate, polyacetal, polystyrene, etc. ABS (acrylonitrile-butadiene-styrene ternary copolymer) resin, polyurethane, fluorine-containing resin, silicone resin, polyphenylene sulfide resin, cellulose, A polyphenylene ether resin or the like, and a copolymer resin such as these. For the inorganic substance, a glass is exemplified: Inorganic sputum or inorganic synovial agent, polymerization of glass fiber, carbon fiber, talc, mica, wollastonite, kaolin clay, layered silicate, calcium carbonate, titanium dioxide, cerium oxide Catalyst residue, etc. - In terms of additives, an organic or inorganic dye or pigment, a flatting agent, a thermal stabilizer, a flame retardant, an antistatic agent may be exemplified. (antistatic agent), deforming agent, ortho chromatic agent, antioxidant, ultraviolet ray absorbing agent, crystal nucleus growing agent, whitening agent Whitening agent), lubricant (lubrieant), impurity scavenging agent, thickner, surface regulator, and the like. Among them, a capturing agent containing a thermal stabilizer or a low molecular weight volatile impurity is preferred. As the heat stabilizer, preferably a 5- or 3- or 3-membered phosphorus compound or a hindered phenol compound, as a trapping agent for a low molecular weight volatile impurity, polyamine or poly is preferable. A polymer or oligomer of an ester type decylamine, a low molecular weight compound having a guanamine or amine group. The film of the copolymer A of the present embodiment is a glass transition temperature measured by the DMA method of at least 30 °C. The glass transition temperature measured by the DMA method is preferably 140 ° C or higher, more preferably 150 ° C or higher. The upper limit of the glass transition temperature measured by the D Μ A method is not particularly limited, but is usually 200 ° C or lower, preferably 180 ° C or lower, more preferably 170 ° C or lower, and even more preferably 160 ° C or lower. . The DM A method is as follows. That is, the test piece is heated from room temperature at 5 ° C /min, and a viscoelasticity measuring device is used to measure the dynamic viscoelasticity and the loss tangent angle of the test piece, from the loss tangent The glass transition temperature can be determined by the peak temperature of the corner. Here, the measurement frequency is set to 1 Hz (hertz). 201221544 Further, the copolymer A film of the present embodiment is a glass transition temperature of 200 t or more as measured by the TMA method. The glass transition temperature 'measured according to the method is preferably 210 ° C or higher, more preferably 220. (The above, more preferably 23 0 ° C or more, particularly preferably 23 5 ° C or more. The upper limit of the glass transition temperature measured by the TMA method is not limited, but is usually 260 t or less, preferably 2 5 5 ° C or less, more preferably 2 5 0 t or less, and even more preferably 2 4 5 ° C or less. Τ Μ A method is as follows. That is, it is made by pressing it at room temperature for one minute/minute. The temperature of the test piece is raised, and the thermal analysis device is used to measure the amount of thermal expansion in the thickness direction. The graph shows the relationship between the temperature and the amount of thermal expansion. The curve before and after the glass transition point is tangent line from the tangent line. The glass transition temperature can be obtained at the intersection of the wires. The 'copolymer A film of the present embodiment is in the range of 22°$20 S24 in the X-ray diffraction. The maximum peak is obtained in the range of this embodiment. The polymer A film is excellent in hydrolysis resistance. The reason why the copolymer A film of the present embodiment can have such characteristics is not clear, but the following facts can be cited as the cause thereof. The characteristics of temperature and maximum peak enthalpy The fact that the copolymer A in the co-polymer A film is crystallized to some extent or more may be due to the fact that the copolymer A is more than a certain degree (based on the degree of crystallization, preferably 20%) The above-mentioned, more preferably, 30% or more of the fact that the hydrolysis resistance is increased. The breaking strength of the copolymer A film of the present embodiment is based on the measurement according to JIS-K7127, MD ( The longitudinal direction of the square-11 - 201221544 is preferably 80 MPa (megapascal) or more, more preferably 90 MPa or more, and more preferably 10 MPa or more in the direction of the .TD (lateral direction). The breaking ductility is preferably 150 MPa or less, more preferably 120 MPa or less, and even more preferably 80 MPa or less in the MD direction and the TD direction in the measurement according to JIS-K7127. The insulation breakdown of the present embodiment The electric breakdown voltage is preferably 90 kV/mm or more, more preferably 1 1 Ok V/mm or more, and still more preferably 1 3 Ok V/mm or more in the measurement according to ASTM D-149. Coefficient of thermal expansion (CTE) Expansion)), in the measurement according to the TMA method (50 to 100 ° C), the MD direction and the TD direction are preferably 80 ppm/° C. or less, more preferably 60 ppm/° C. or less, and still preferably 40 ppm/ The thickness of the copolymer A film of the present embodiment can be appropriately selected depending on the thickness of the back surface protective sheet for a solar cell module and the desired properties, and is preferably ΙΟμηι to 500 μmη, more preferably 20 μηι. 300 μηι, and preferably 30 μηι to 200 μιη. When such a range is formed, the production of the film is facilitated, and the handling property or the post-processability are facilitated by the increase in strength and rigidity. The thickness deviation is preferably within ±10%, more preferably within ±7%, and even more preferably within ±5%. The copolymer film of the present embodiment can be produced in the following manner. First, a copolymer A resin (for example, a -12-201221544 pellet) to be a raw material is prepared. The copolymer A resin can be produced by a known method, and a polycondensation of 4-cyclohexanedimethanol, terephthalic acid, and isophthalic acid can be produced. Further, the copolymer a pellet is also commercially available from Eastman, for example, under the trade name "Eastman Copolyester 13319". Then, the copolymer A resin is melted by heating, and if necessary, an additive ' is added to obtain a resin composition containing the copolymer A. Then, this resin composition was molded into a film. The method of molding into a film may be a method in which a resin composition containing a copolymer A is extruded in a molten state from a die to form a molding method. A solution in which a resin composition is dissolved in a solvent is applied onto a support, and then a solvent-dried solution casting method or the like is applied. Among these, the melt-molding method of the film can be obtained in a process which is excellent in productivity and environmental aptitude. In the melt molding method, a T-die or an I-die or a water-cooled and air-cooled film injecting filming method is preferred. Next, the stretching of the formed unstretched copolymer A film is carried out to obtain the above-mentioned copolymer a film of the present embodiment. The stretching condition or the stretching method is not particularly limited, and can be appropriately adjusted within a range in which the above-mentioned glass transition temperature can be obtained or a maximum peak value can be obtained within a predetermined angle range in X-ray diffraction. For example, the direction of extension may be uniaxial or biaxial, but preferably biaxial. -13- 201221544 The stretching method is not particularly limited, and various methods such as roll-type drawing and tenter drawing can be used in a single mode or in any combination. The stretching ratio (e 1 ο n g a t i ο n r a t i 〇) is also not particularly limited. For example, it can be 2 to 5 times in the MD (machine direction) direction and 2 to 5 times in the TD (transverse direction). An embodiment of the configuration of the back surface protective sheet for a solar cell module of the present invention (hereinafter, simply referred to as "back surface protective sheet") is shown in Fig. 1. The back surface protective sheet 1 has a heat-resistant film substrate 30, 32 formed on both sides of a gas barrier film 20. The gas barrier film 20 is formed by providing a vapor deposition layer 12 made of an inorganic compound on one surface of the substrate 10. As the substrate 10, the above-mentioned copolymer A film can be used. The heat-resistant film substrates 30, 32 used in the present embodiment are preferably heat-resistant, and may be, for example, a polyethylene terephthalate (PET) film or a poly Fluorinated vinyl resin (PVF) film, polyvinyl fluoride resin (PVDF) film, polytrifluoroethylene chloride resin (PCTFE) film, ethylene-tetrafluoroethylene copolymer (ETFE) film, polytetrafluoroethylene A fluorine-containing substrate of a tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA) film of an ethylene (PTFE) film. Further, as the heat-resistant film substrate 30, 32, the copolymer A film is also suitably used. The thickness of the film substrates 30, 32 is not particularly limited, and is, for example, preferably 3 to 200 μm, more preferably 6 to 30 μm. The material of the vapor-deposited layer 1 2 is not particularly limited, and examples thereof include a mixture of two or more of aluminum oxide, cerium oxide, tin oxide, magnesium oxide, and zinc oxide. The thickness of the vapor-deposited layer 12 is not particularly limited, and is, for example, preferably 5 to 300 nm, more preferably 1 to 15 nm. For the method of laminating the gas barrier film 20 of the present embodiment and the heat-resistant film substrate 30, 32, for example, the gas barrier film 20 and the film substrate having heat resistance can be used. 30, 32, a lamination of dry lamination via a tackifier as needed for lamination. In the dry laminating adhesive, it is necessary to prevent delamination due to deterioration of the adhesive strength for a long period of time, and further, the adhesive does not yellow (yellowing). For the purpose of high heat resistance, wet heat resistance, etc., it is preferred to use a resin or the like as a component of a vehicle constituting the adhesive, which can be crosslinked and hardened. A three-dimensional mesh-like cross-linking structure. Specifically, the adhesive constituting the above-mentioned pressure-sensitive adhesive layer for lamination preferably has a crosslinked structure due to reaction energy by heat or light in the presence of a curing agent or a crosslinking agent. For example, an aliphatic/alicyclic isocyanate such as a two-fluid hardening type polyurethane or an isocyanate curing agent or a crosslinking agent such as an aromatic isocyanate In the presence of heat, or the reaction energy of light, the adhesive is laminated to form a crosslinked structure, and it is possible to manufacture a back surface protection for solar cell modules excellent in heat resistance, weather resistance, and moist heat resistance. sheet. -15- 201221544 In the above-mentioned adhesive, for the aliphatic isocyanate, for example, 1,6-extended hexyl diisocyanate (HDI) or an alicyclic isocyanate can be used, for example, isophorone can be used. For isocyanate (IPDI) and aromatic isononates, for example, toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), naphthalene diisocyanate (NDI), dimethylbiphenyl can be used. Isocyanate (TODI), benzoyl diisocyanate (XDI), and the like. Further, in the above-mentioned adhesive, an ultraviolet absorber or an optical stabilizer may be added for the purpose of preventing ultraviolet ray deterioration or the like. The amount of use varies depending on the particle shape, density, etc., but is preferably about 0.1 to 10% by weight. The above adhesive agent can be, for example, a roll coating method, a gravure coating method, a kiss roll coating method, another coating method, or a printing method. (printing) or the like, and the coating amount thereof is about 2 to 20 g/m 2 (dry state), preferably 3 to 10 g/m 2 (dry state), and in the above constitution. In the case of the heat-resistant film substrate 30, 32, a resin which has been previously formed into a film shape is laminated on the gas barrier film 20, but it may be used without The heat-resistant coating liquid is applied to the gas barrier film 20, and dried as necessary to form a film substrate 30, 32 laminated on the gas barrier film 20. The coating method is applicable to a roll coating method, a concave roll coating method, a roll coating method, another coating method, or a printing method of -16-201221544. The coating amount is preferably in the range of 1 to ΙΟΟμηη (dry state), preferably 5 to 50 μm (dry state). The back protective sheet for a solar cell module of the present invention obtained in this manner has the above-mentioned copolymer ruthenium film, and is particularly superior to hydrolysis resistance. Therefore, such a back surface protective sheet for a solar cell can protect a solar cell for a long period of time and is inexpensive. Further, the configuration of the back surface protective sheet for a solar cell module is not limited to the above configuration. For example, between the vapor deposition layer 12 and the substrate 10, a transparent primer layer may be provided for the purpose of improving the adhesion between the layers. The resin of the transparent primer layer may, for example, be a silane coupling agent or a hydrolyzate thereof, or a complex with a polyol and an isocyanate compound. As the organic decane coupling agent, for example, ethyl trimethoxy decane, vinyl trimethoxy decane, r-chloropropyl methyl dimethoxy decane, r-chloropropyl trimethoxy decane, glycidyl oxy propylene can be used. One or two or more kinds of organic decane coupling agents such as methoxytrioxane, r-methyl propyloxypropyltrimethoxy hydride, and r-methyl propylene oxypropyl methyl dimethyl hydride, or a hydrolyzate thereof. Further, for example, those containing an isocyanate group such as r-isocyanate propyl triethoxy decane or r-isocyanate propyl trimethoxy decane, or a fluorenyl group containing, for example, r-mercaptopropyltriethoxy decane, or Such as r-aminopropyl triethoxy decane, r-aminopropyl trimethoxy decane, N- s-(aminomethyl)-r-aminopropyltriethoxy decane, r-phenylamino Propyltrimethoxine-17- 201221544 Alkane-based amine base. Further, it contains an epoxy group such as r-glycidoxypropyltrimethoxysilane or yS-(3,4-epoxycyclohexyl)ethyltrimethoxyoxane, or such as vinyltrimethoxysilane or ethylene. In addition, an organic alcohol or the like may be added to the organic decane coupling agent such as a thiol-methoxy oxane, and a hydroxyl group or the like may be added thereto, and one type or two or more types may be used. In the case of a polyhydric alcohol, for example, an acrylic acid derivative monomer such as ethyl methacrylate, hydroxyethyl methacrylate or hydroxypropyl methacrylate or hydroxybutyl methacrylate is polymerized in a separate manner, or A propylene-based polyol or the like which is obtained by adding another monomer such as styrene and then copolymerizing it is suitably used. As the isocyanate compound, for example, an aromatic toluene diisocyanate (TDI) or diphenylmethane diisocyanate (MDI), an aliphatic benzodimethyl diisocyanate (XDI) or a hexamethylenemethyl group can be used. A monomer such as a diisocyanate (HMD I) or a polymer or a derivative thereof, and one or more of these may be used. The thickness of the transparent primer layer is not particularly limited, but is preferably 0.001. Further, it is also possible to provide a gas barrier layer overcoat layer between the vapor deposition layer 12 and the film substrate 32 to 2 μm, more preferably 〇.〇3 to 0·5μηιο. The protective film layer, for example, 'containing a water-soluble polymer, and one or more alkoxides or a hydrolyzate thereof, and applying a coating liquid containing water or a water/alcohol mixture as a solvent to the vapor deposition layer 12 It can be formed on the top. The water-soluble polymer may, for example, be polyvinyl alcohol, polyvinyl pyrrolidone, starch, methyl cellulose, carboxymethyl cellulose, sodium alginate-18-201221544 (sodium alginate), etc. In addition, tetraethoxy decane, sodium triisopropoxide, etc. are mentioned. Further, the vapor deposition layer 12 may be formed on both surfaces of the substrate 10. In this case, the transparent primer layer or the protective layer may be formed on both sides of the vapor deposition surface. Further, for example, when the back surface protective sheet for a solar cell module is applied to a solar cell module having a low gas barrier property, the solar cell module back surface protective sheet can be formed without the vapor deposition layer 1 2 State. In this case, a heat-resistant film substrate 3 0, 32 is formed on one or both sides of the substrate 1 . Further, the back surface protective sheet 1 for a solar cell module may not have either or both of the film substrates 30, 32, or may be composed only of the above-mentioned substrate 10. Next, a description will be given of a solar cell module using the back protective sheet for a solar cell of the present invention. Fig. 2 is a schematic cross-sectional view showing a solar battery module 100 having a back protective sheet for a solar cell of the present invention. In the solar battery module 100 of the present embodiment, the solar cell module surface protection sheet 60 and the surface side ruthenium layer 5 are disposed on the back side of the solar cell module 1A. 1. A solar cell element 50 as a photoelectromotive element of the wiring 52, a back side sputum layer 53, and a film substrate 30 having the above hydrolysis resistance of the back surface protective sheet 1 . -19-201221544 These members can be formed by, for example, a lamination method such as vacuum calcining by vacuum suction or the like, or a lamination method such as heating calendering. Each of the above layers is subjected to hot calender molding as a body molded product. Further, the solar battery module 1 〇〇 ' may also be mounted with a frame (not shown) made of, for example, aluminum. The surface protection sheet 60 for a typical solar battery module constituting the above-described solar battery module has weather resistance, heat resistance, light resistance, water resistance, and resistance from sunlight penetration, insulation, and the like. Wetness, antifouling property, other various characteristics, superior to physical or chemical strength, toughness, etc., and excellent in durability, and further, as a protection of a solar cell element of a photovoltaic element, It is required to be superior to scratch resistance, impact absorption, and the like. Specifically, a known glass plate or the like can be used, and for example, a polyamide resin (various nylon), a polyester resin, a cyclic polyolefin resin, a polystyrene resin, or the like can be used. Acrylic resin, polycarbonate resin, acetal resin, various other resin films or sheets, and copolymer A is also suitably used. For the film or sheet of the above resin, a stretched film or sheet which is biaxially oriented may be used. Further, the thickness of the film or sheet of the resin may be a minimum thickness required to maintain strength, rigidity, elastic recovery strength, etc., and if it is too thick, there is a disadvantage that the cost increases. If it is too thin, strength, rigidity, and strength of strength recovery will be lowered. In the present embodiment, the thickness of the film or sheet of the resin is preferably from 12 to 200 μm, more preferably from -20 to 201221544 25 μη to 150 μm, for the above reasons. In the case of the ruthenium layer 5 层压 laminated under the surface protection sheet 60 for the solar cell module constituting the solar cell module, since the sunlight is incident through the surface protection sheet 60, and after the penetration It needs to have transparency for absorption. In addition, it is also required to have adhesiveness between the surface protection sheet and the back surface protection sheet. In addition, it has thermoplasticity from the function of maintaining the smoothness of the surface of the solar cell element as a photovoltaic element, and further, in order to protect the solar cell element as a photovoltaic element, it is required to be superior to scratch resistance. Impact absorption and the like. Specifically, as the above-mentioned smear layer, for example, an ethylene-acetic acid ethylene co-polymer, an ionomer resin, an ethylene-acrylic acid, or an 'acid-modified polyolefin resin, a poly-polymer can be used. One or a mixture of two or more of a vinyl butyral resin, an anthrone-based resin, an epoxy resin, a (meth)acrylic resin, and another resin. In the present embodiment, in order to improve the weather resistance of heat resistance, light resistance, water resistance, etc., the resin constituting the above-mentioned enamel layer can be arbitrarily added, for example, within a range that does not affect the transparency. , a crosslinking agent, a thermal oxidation inhibitor, a photostabilizer, a UV absorber, a photooxidation inhibitor, other additives, and a mixture. In the present embodiment, the ethylene-vinyl acetate system is used in consideration of performance and price in consideration of weather resistance such as light resistance, heat resistance, and water resistance. Resin is a very suitable material. Here, the thickness of the above-mentioned enamel layer is preferably from 200 to ΙΟΟΟμη, more preferably from 350 to 600 μm. As a solar cell 21 - 201221544 cell element 50 constituting a photovoltaic element of a solar cell module, 'a crystal can be used, for example, a crystal of a single crystal 太阳能 type solar cell element, a polycrystalline 矽 type solar cell element, etc.矽Solar electronic components, ado〇rph〇us silicon solar cell elements, gallium arsenide (GaAs) or phosphating, formed by single junction type, tandem structure type, etc. A Group III-V compound semiconductor solar cell element such as indium (InP), a Group II-VI compound semiconductor solar cell element such as cesium telluride (cdTe) or copper indium selenide (CulnSe2), an organic solar cell element, or the like. Further, a thin film polycrystalline solar cell element, a thin film microcrystalline solar cell element, a thin film crystal solar cell element, and a hybrid element of an amorphous germanium solar cell element can also be used. The back side side enamel layer 53 laminated under the photoelectromotive force element constituting the solar cell module can be used and filled on the surface side to be laminated under the surface protection sheet for the solar cell module. The material layer 5 1 is of the same material. It is also required to have adhesiveness with the back surface protective sheet, and to have thermoplasticity in order to maintain the smoothness of the back surface of the solar cell element as a photovoltaic element, and to protect the solar cell as a photovoltaic element. From the viewpoint of components, it is required to be superior to scratch resistance, impact absorption, and the like. According to the solar cell module of the present invention described above, since the above-mentioned copolymer A film is used for at least one of the back surface protective sheet and the surface protective sheet, the hydrolysis resistance of the back surface protective sheet or the surface protective sheet is higher. high. Therefore, when compared with the case of using polyethylene terephthalate (PET) film or polyethylene naphthalate (PEN) film, -22-201221544 can be maintained as a solar cell for a long time. Power output characteristics. Further, the solar battery module is not limited to the above configuration, and can be configured in various forms. For example, as the back surface protective sheet 1, various configurations as described above can be employed. In short, it is preferable to provide a surface layer including a solar cell element 50 and a surface protective sheet disposed on the surface of the surface layer. 60. The back protective sheet 1 disposed on the back surface of the adhesive layer, and at least one side of the surface protective sheet 60 and the back protective sheet 1 may include the above-mentioned copolymer A film. [Embodiment] [Examples] Hereinafter, the present invention will be described in more detail by way of examples and comparative examples. Here, the present invention is not limited by the following examples. As the raw material of the film, the following resin particles were used. Here, PEN is polyethylene naphthalate. (1) Co-watering substance A (made by Eastman Co., Ltd. 'trade name · Eastman Copolyester 13319) (2) PEN (manufactured by Teijin DuPont Film Co., Ltd., trade name: Iron Onyx Q51) (3) 1,4- Cyclohexanedimethanol · 2,2,4,4_tetramethyl-indole, 3 •cyclobutanediol • p-phthalic acid polycondensate (manufactured by Eastman Co., Ltd., trade name: Eastman Triun CoP〇lyester FX200) (hereinafter, simply referred to as "copolymer b") -23-201221544 [Example i] Thin film formation by melt extrusion of copolymer A (granular form), and further biaxially oriented stretching An extended copolymer ruthenium film having a thickness of 50 μm was obtained. [Example 2] A copolymerization film having a thickness of 100 μm was produced in the same manner as in Example 1 except that the elongation ratio was changed to 厚度μπι. [Comparative Example 1] Thin film was formed by melt extrusion of PEN (granular), and biaxially oriented stretching was further carried out to obtain an extended PEN film having a thickness of 25 μm. [Comparative Example 2] A film of unstretched copolymer A having a thickness of ΙΙΟμηι was obtained by melt-extruding the copolymer A (granular). [Comparative Example 3] A film of unstretched copolymer B having a thickness of 100 μm was obtained by melt-extruding the copolymer B (granular). <Various physical properties> The films of Examples 1 and 2 and Comparative Examples 1 to 3 were measured for fracture, 24-201221544 strength, fracture ductility, glass transition temperature, melting point, dielectric breakdown voltage, specific gravity, and thermal expansion coefficient. The measurement method and measurement enthalpy of each measurement are shown in Table 1. [Table 1] Film _ film thickness copolymerization post extension PEN extension copolymer A unstretched copolymer Β Unextended 50 μ mt〇〇ii m 25/1 m 110μτη 100 μ π Item measurement method Example 1 Example 2 Comparison Example 1 Comparative Example 2 Comparative Example 3 Breaking strength (MPa) MO 120 100 180 50 50 TD too 100 200 50 50 MO 50 80 30 200 120 (70) TD 60 80 20 210 120 Glass transition temperature (it) DMA 155 165 112 141 TMA 240 240 98 121 Melting point (°c) DSC 285 269 285 - Releasing the breakdown voltage (kV/mm) ASTM D-149 1B0 130 200 80 110 Specific gravity ASTM D-792 1.24 1.3G 1.195 1.17 Thermal expansion coefficient MD 29 37 1 138 109 [50-100*0] (ppm/t) TO 39 38 4 114 98 <Hydrolysis test> The pans of Examples 1 and 2 and Comparative Examples 1 to 3 were subjected to a pressure cooker test (1 20 ° C, 1 〇〇 % RH (relative humidity), 2 atm). For each of the films, the tensile strength retention ratio and the tensile elongation retention ratio after 50 hours, 1 hour, 15,000 hours, and 200 hours were measured. The results are shown in Figures 3 and 4. The films of Examples 1 and 2 were slower than the films of Comparative Examples 1 to 3 in terms of tensile strength retention and tensile elongation retention. <Measurement of crystallinity (crystaUinity)> -25-201221544 For the films of Example 1, Example 2, and Comparative Example 2, powder X-ray diffraction using Cuk®: The diffraction characteristic curve (diffracti0I1 pattern) was confirmed and the crystallinity was calculated. The measurement method and measurement conditions are as follows. Target: Cu (copper), X-ray tube current: 40 mA, X-ray tube voltage: 45 kV, scan width: 20 = 4 to 65. Step: 2 0 =0.01 671. , average time / step: 10.160s (seconds) 'fixed divergent slit: 1/2. , Rotation speed: 60 rotations per minute, crystallographic analysis (CrytaHinity analysis): Harmans method, pre-treatment: None. The relationship between the angle 20 of the incident direction of the X-ray and the direction of the reflection and the diffraction strength is shown in Fig. 5. In the films of Examples 1 and 2, a sharp sharp maximum peak was confirmed in the range of 22 ° $ 20 $ 24 °, but the presence of sharp peaks was not confirmed in the film of Comparative Example 2, It is known that the system is amorphous. Further, according to Fig. 5, the crystallinity of the films of Examples 1 and 2 was determined to be 42.8% and 39.7 %, respectively. Further, in Examples 1 and 2, the second strong peak 出现 appeared at 20 = 16 to 17°, and the third strong peak 出现 appeared at 20 = 19 to 20°. The peak intensity ratio is the second strongest peak / maximum peak 値 = 〇 · 1 to 0.2 degree. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a cross-sectional view showing a back protective sheet for a solar cell module according to an embodiment of the present invention. -26- 201221544 Fig. 2 is a schematic cross-sectional view showing a solar battery module according to an embodiment of the present invention. Fig. 3 is a graph showing the change with time in the tensile strength retention rate in the pressure cooker test for the films of Examples 1, 2 and Comparative Examples 1 to 3. Fig. 4 is a graph showing the change of the tensile ductility retention ratio in the pressure cooker test with respect to the films of Examples 1, 2 and Comparative Examples 1 to 3. Fig. 5 is a graph showing the results of X-ray diffraction of the films of Examples 1, 2 and Comparative Example 2. [Description of main component symbols] 1 : Back surface protection sheet for solar cell module 10 : Substrate 1 2 : Distillation layer 20 : Gas barrier film 3 0, 32 : Film substrate 5: Solar cell element 5 1 : Surface side enamel layer 52 : Wiring 5 3 : Back side 塡 filling layer 6 〇: Surface protection sheet for solar cell module 100 : Solar battery module -27-