201141930 六、發明說明： 【發明所屬之技術領域】 本發明係關於一種太陽能電池模組用封止材薄片及太 陽能電池模組。 【先前技術】 近年來作爲利用太陽光之潔淨的發電技術，太陽能電 池正引人注目。習知一般之太陽能電池模組係使太陽能電 池單元包埋而封止於封止材層內，利用表面保護構件與背 面保護構件而保護該封止材層兩面側之模組。該太陽能電 池模組之製造方法係廣泛採用如下之方法：依照表面保護 構件、封止材薄片、太陽能電池單元、封止材薄片及背面 保護構件而積層，於真空中加熱此等而使其脫氣之後，一 邊於真空中施加一大氣壓之載重且一邊進行加熱，使太陽 能電池單元包埋，同時也使封止材樹脂交聯硬化而進行接 著一體化。 一般而言，作爲封止材薄片之材料，成爲主要成分之 樹脂係使用EVA (乙烯/醋酸乙烯共聚物）》最爲一般之太 陽能電池用之封止材薄片係單層構造者’至少交聯劑添加 有有機過氧化物（例如，專利文獻1至5)。藉由含有有 機過氧化物且藉熱而使有機過氧化物分解而產生自由基， 來將EVA予以交聯。如此方式，藉由依照有機過氧化物來 交聯EVA而能夠將太陽能電池單元固定於太陽能電池模組 之封止材層中。另外，於封止材薄片中’使其耐久性提高 201141930 之目的下，大多以一定比例含有交聯助劑、矽烷耦合劑、 光安定劑、紫外線吸收劑之添加物。 封止材薄片之製造方法，例如採用從具有直線狀狹縫 之模頭而以熔融狀態擠出形成封止材薄片之樹脂，利用冷 卻輥或水槽進行急冷固化之T模頭法、或壓延法等之製膜 步驟。藉該製膜步驟而成膜500 μπι左右之厚度的封止材薄 片。另外，於該製膜步驟之中，也有實施將凹凸賦予封止 材薄片表面之壓紋加工。 〔先前技術文獻〕 ‘ 〔專利文獻〕 專利文獻1 :日本特開平9 -27 63 3號公報 專利文獻2 :日本特開平1 1 -547 68號公報 專利文獻3:日本特開2000-183381號公報 專利文獻4:日本特開2005-126708號公報 專利文獻5:日本特開2006-186233號公報 【發明內容】 〔發明所欲解決之問題〕 然而，如專利文獻1至5所記載的習知封止材薄片， 若於輸送後或一定期間之保管後使用時，太陽能電池模組 中之封止材層的交聯率將降低，太陽能電池模組之耐久性 將顯著降低。 另外，於封止材薄片之製造中，由於根據條件而於薄 片中發生凝膠，防止薄片成形時之凝膠的發生係重要。 本發明之目的係提供一種太陽能電池模組用封止材薄 201141930 片，不會使凝膠發生而能夠成形，即使輸送後或一定期間 之保管後使用，也能夠形成高的交聯率之封止材層’能夠 安定地製造具有優異的耐久性之高品質太陽能電池模組。 另外，本發明之目的係提供一種高品質的太陽能電池模 組，其係使用該太陽能電池模組用封止材薄片之具有優異 的耐久性。 〔解決問題之手段〕 本發明係爲了解決該課題而採用以下之構造： 〔1〕一種太陽能電池模組用封止材薄片，其係含有乙烯/ 醋酸乙烯共聚物與有機過氧化物之太陽能電池模組用封止 材薄片；該有機過氧化物係符合下列條件（A )及條件（B )， 並且該有機過氧化物的含量係相對於該乙烯/醋酸乙烯共 聚物100質量份爲0.4至1.0質量份。 (A) 在具有半徑爲1.8 cm之底面、深度爲0.9 cm之 圓筒容器內，以50 °C之條件下，5小時保管0.15 g之有機 過氧化物時之揮發量爲1 5質·量％以下。 (B) 有機過氧化物在1小時減半之分解溫度爲115 至 140°C。 〔2〕一種太陽能電池模組，其係具有太陽能電池單元、封 止該太陽能電池單元之封止材層、保護該封止材層表面側 之表面保護構件、與保護該封止材層背面側之背面保護構 件；該封止材層係藉由該〔1〕記載之太陽能電池模組用封 止材薄片所形成。 〔發明之效果〕 201141930 本發明之太陽能電池模組用封止材薄片係不會使凝膠 發生而能夠成形，即使於輸送後或一定期間之保管後使 用’也能夠形成高的交聯率之封止材層，能夠安定地製造 具有優異的耐久性之高品質太陽能電池模組。 另外，由於本發明之太陽能電池模組係使用本發明之 太陽能電池模組用封止材薄片，具有高的交聯率之優異的 封止材層將被安定地形成，且具有優異的耐久性之高品質。 【實施方式】 <太陽能電池模組用封止材薄片> 本發明之太陽能電池模組用封止材薄片（以下，簡稱 爲「封止材薄片」）係於太陽能電池模組中，用於封止太 陽能電池單元之封止材層形成的薄片，含有乙烯/醋酸乙烯 共聚物（EVA )與有機過氧化物。 形成本發明之封止材薄片的樹脂基材較佳爲使用作爲 主要成分之EVA。EVA係具有高的透明性且廉價，尤其在 過去的使用績效龐大之點爲有利。所謂以EVA作爲主要成 分係意指相對於樹脂基材之總量而使EVA成爲9 5質量％ 以上。 於本發明之封止材薄片中，除了 EVA以外，也可以含 有其他之樹脂。其他之樹脂可舉例：聚乙烯、聚丙烯等之 聚烯烴；離子聚合物；乙烯-甲基丙烯酸共聚物；乙烯-丙 烯酸共聚物；聚氟乙烯；聚氯乙烯、或此等之共聚物等。 本發明之封止材薄片的樹脂基材中之EVA比例較佳爲 201141930 95質量％以上，更佳爲97質量％以上，特佳爲100質量 %。 該樹脂基材之MFR (熔融流動速率）較佳爲20至40 g/l〇分鐘。若樹脂基材之MFR爲共聚物的話，藉由調節源 自共聚物成分之單位的含有率而能夠調節。EVA之MFR係 藉由調節EVA 100質量％中之醋酸乙烯單位的含有率而能 夠調節。 EVA所具有的全部單位100質量％中之醋酸乙烯單位 的贪有率較佳爲20至40質量％，更佳爲25至35質量％。 另外，MFR也藉由調節分子量而能夠調節，藉由增大 分子量而使MFR變小。 該MFR係利用依照ASTMD 1 23 8之方法而予以測出》 本發明之封止材薄片之特徵爲交聯劑係含有符合下列 條件（A )及條件（B )之有機過氧化物（以下，稱爲「有 機過氧化物I」）。 (A)在具有半徑爲1.8 cm之底面、深度爲〇.9 cm之 圓筒容器內，以50 °C之條件下，5小時保管0.15 g之有機 過氧化物時之揮發量爲15質量％以下。 (B )有機過氧化物在1小時減半之分解溫度爲1 1 5 至 140°C。 習知使用輸送後之封止材薄片、或保存一定期間後之 封止材薄片而製造太陽能電池模組之情形下，封止材層之 交聯率將降低’所獲得之太陽能電池模組之耐久性將顯著 201141930 降低。針對於此，本發明人等進行詳細探討後得知：於輸 送後、或保存一定期間後之封止材薄片中，在該封止材薄 片中所含有的有機過氧化物將揮發，其量將減少。因此， 本發明人等發現：藉由使用符合該條件（A)之有機過氧化 物I而抑制有機過氧化物從封止材薄片揮發，使用輸送後 或保存一定期間後之封止材薄片，也能夠安定地製造高品 質之太陽能電池模組。 另外，有機過氧化物I係以1小時減半之分解溫度爲 115至140 °C。若有機過氧化物I之該分解溫度爲115 °C以 上的話，能夠抑制於薄片成形時交聯反應將進行而在封止 材薄片內發生凝膠。另外，若有機過氧化物I之該分解溫 度爲1 40°C以下的話，於太陽能電池模組製造之際，由於 交聯反應將充分進行，封止材層之交聯率將變高，可以獲 得具有優異的耐久性之太陽能電池模組。 有機過氧化物I較佳爲三級丁過氧-2-乙基己基單碳酸 酯（條件（A )之揮發量：7 · 2質量％、條件（B )之熱分 解溫度：1 1 9 °C )。 本發明之封止材薄片中所含有的有機過氧化物I較佳 爲1種。有機過氧化物I含有2種以上之情形，由於此等 有機過氧化物I之揮發性不同，擔憂於經過一定期間後之 封止材薄片內’每1種有機過氧化物I之比率將改變而變 得不均勻。但是，若有機過氧化物I爲1種的話，即使經 過一定期間後，也容易保持封止材薄片內之有機過氧化物 201141930 I之均勻性，容易縮小使用該封止材薄片所製造的太陽 池模組特性之偏異。 另外，於太陽能電池模組之製造中，通常於利用 封止材薄片而夾住太陽能電池單元之狀態下，於真空 邊施加載重且一邊進行加熱，使太陽能電池單元包埋 時也使封止材樹脂交聯，於此等二片封止材薄片中， 所含有的有機過氧化物I較佳爲相同。若使用含有相 有機過氧化物I的封止材薄片的話，由於即使經過一 間後，二片封止材薄片間之有機過氧化物I的量幾乎 且也容易抑制不均勻化，容易縮小太陽能電池模組之 的偏異。 本發明之封止材薄片中之有機過氧化物I的含量 對於EVA 100質量份爲0.4至1.0質量份，較佳爲0 0.8質量份。若有機過氧化物I的含量係相對於EVA 質量份爲0.4質量份以上的話，能夠形成交聯率爲高 止材層，故能夠製造具有優異的耐久性之太陽能電 組。若有機過氧化物I的含量係相對於EVA 1 00質量 1 .〇質量份以下的話，能夠抑制於薄片成形時交聯反應 行而在封止材薄片內發生凝膠。 另外，於本發明之封止材薄片中’除了該有機過 物之外，也可以含有促進交聯反應之交聯助劑。交聯 可舉例：異氰酸三烯丙酯、鄰苯二酸二烯丙酯、氰酸 丙酯等。 能電 二片 中一 ，同 各自 同之 定期 同等 特性 係相 .5至 100 的封 池模 份爲 將進 氧化 助劑 三烯 -10- 201141930 另外，於本發明之封止材薄片中，在太陽能電池模組 內，爲了使封止材層與表面保護構件及背面保護構件之接 著性提高，也可以含有矽烷耦合劑。矽烷耦合劑可列舉：γ -甲基丙烯醯氧丙基三甲氧基矽烷、三甲氧基丙基矽烷、三 甲氧基甲基矽烷、乙烯三甲氧基矽烷、乙烯三乙氧基矽院、 三氯丙基矽烷、三乙氧基苯基矽烷等。 另外，於本發明之封止材薄片中，用以使所形成的封 止材層之耐久性提高，也可以含有紫外線吸收劑、抗氧化 劑等之安定化劑。 用以提高耐光性所用之紫外線吸收劑，可舉例：2 - ( 5 -甲基-2-羥苯基）苯并三唑、2-( 3·三級丁基-5-甲基-2-羥苯 基）-5-氯苯并三唑、2-(4,6-二苯基-1，3,5-三阱-2-基）-5_ 〔（己基）側氧〕酚、2,4-二羥基-4_二苯甲酮、2-羥基ΙΕ 辛氧基 二苯甲 酮等。 用以提高熱安定性所用之抗氧化劑，可舉例：1,6-己 二醇雙〔3-(3,5-二（三級丁基）-4-羥苯基）丙酸酯〕、 季戊四醇四〔3-(3,5-二（三級丁基）-4-羥苯基）丙酸酯〕、 三（2,4-二（三級丁基）苯基）亞磷酸酯、2，4-雙（正辛硫 基）-6-(4-羥基-3,5-二（三級丁基）苯胺基）-i，3,5-三 口井、十八院基-3- (3,5 - 一（二級丁基）-4· -經苯基）丙酸醋 等。 (封止材薄片之製造方法） 本發明之封止材薄片除了交聯劑使用上述之有機過氧 -11 - 201141930 化物I以外，也能夠利用習知之製造方法而製造。例如’ 可舉例具有如下之製膜步驟的方法：使用τ模頭等’利用 擠出已將有機過氧化物及必要時所添加的添加劑混入該樹 脂基材中而使其加熱熔融的樹脂之共擠出法，來進行封止 材薄片之製膜。 另外，於該製膜步驟中’爲了防止結塊’藉由使熱熔 融的狀態之樹脂薄片表面貼合於已實施凹凸圖案的輥（金 屬或橡膠製）上，使該輥之凹凸圖案轉印至該樹脂薄片單 面或雙面，對封止材薄片實施壓紋加工。 以上所說明的本發明之封止材薄片已抑制於薄片成形 時發生凝膠。另外，不論於輸送後或保存一定期間後，皆 已抑制薄片中之有機過氧化物揮發而使其量減少。因此， 若爲本發明之封止材薄片的話，即使經過一定期間後之封 止材薄片也安定地形成具有高的交聯率之封止材層，能夠 安定地製造具有優異的耐久性之高品質太陽能電池模組。 <太陽能電池模組> 本發明之太陽能電池模組係具有：太陽能電池單元、 封止該太陽能電池單元之封止材層、保護該封止材層表面 側之表面保護構件、與保護該封止材層背面側之背面保護 構件；該封止材層係藉由上述本發明之太陽能電池模組用 封止材薄片所形成的模組。以下，顯示本發明之太陽能電 池模組的實施形態之一例而詳加說明。 如第1圖所示’本實施形態之太陽能電池模組1係具 -12- 201141930 有太陽能電池單元4，4、封止太陽能電池單元4，4之封止 材層3、保護封止材層3表面側之表面保護構件2、保護封 止材層3背面側之背面保護構件5。 (太陽能電池單元） 太陽能電池單元4係一種依照光電效果而具有受光面 射入之光轉換爲電的機能之單元。太陽能電池單元4係於 太陽能電池模組1內，藉電極（省略圖面）而連接複數個 (於第1圖中爲2個）。太陽能電池單元4之數目並未予 以特別限定。 太陽能電池單元4之材料，例如，可舉例：結晶系矽。 其中，從製造簡便性與成本面之觀點，特佳爲多結晶矽。 (封止材層） 封止材層3係使太陽能電池單元4，4包埋而封止之 層，藉由本發明之封止材薄片所形成。 封止材層3之厚度較佳爲0.3至0.6 mm。 (表面保護構件） 表面保護構件2較佳爲具有優異的耐久性、耐候性、 透明性等，例如，可舉例：玻璃板、聚對苯二甲酸乙二酯 等之樹脂薄片等。另外，也可以使用聚碳酸酯等之樹脂薄 片。 表面保護構件2之厚度較佳爲3至6 mm。 (背面保護構件） 背面保護構件5較佳爲具有優異的耐久性、耐候性 -13- 201141930 者’例如，可列舉：聚對苯二甲酸乙二酯、聚氟乙烯、EVA 等之樹脂薄片、及此等之積層體等。另外，也可以在該樹 脂薄片或積層體上積層賦予水蒸氣遮斷性、氧氣遮斷性之 遮斷層。 背面保護構件5之厚度較佳爲0.2至0.4 mm。 (製造方法） 以下，本發明之太陽能電池模組的製造方法之一例係 說明上述太陽能電池模組1之製造方法。但是，本發明之 太陽能電池模組之製造方法並不受以下之方法所限定。 如第.2圖所示，依序積層表面保護構件2、封止材薄 片3A、太陽能電池單位4，4、封止材薄片3B、表面保護構 件5而作成積層體1A。接著，進行真空狀態下加熱加壓積 層體1A之真空積層，使太陽能電池單位4，4埋沒於封止 材薄片3A、3B內，使封止材薄片3A、3B之樹脂基材（EVA) 交聯硬化而接著一體化來使封止材層3形成。藉此，可以 獲得太陽能電池模組1。 封止材薄片3A與封止材薄片3B係本發明之封止材薄 片’可以爲相同組成之封止材薄片，也可以爲不同組成之 封止材薄片’藉由形成均勻之交聯構造，從容易可以獲得 良好品質的模組之觀點，較佳爲相同組成之封止材薄片。 由於以上所說明的太陽能電池模組係使用本發明之封 止材薄片’即使該封止材薄片爲輸送後或保管—定期間後 之封止材薄片，也具有封止材層之交聯率高且優異的耐久 性而爲高品質。 -14- 201141930 〔實施例〕 以下，顯示實施例及比較例而ί 本發明係根據以下之記載而未予以 在本實施例所用之有機過氧化 量％ )係將0.1 5 g之有機過氧化电 cm、深度爲〇.9 cm之圓筒容器中， 小時，由保管前後之質量所算出。 〔使用原料〕 以下顯示在本實施例所使用的 (EVA ) EVA-1 :醋酸乙烯單位之含有: 爲30 g/1〇分鐘之EVA。 (有機過氧化物） I- 1 :三級丁過氧-2-乙基己基| Π-1 : 1，1_二（三級 丁過氧）_ II- 2:2,5-二甲基-2,5-二（三 | (交聯助劑） ΠΙ-1 :三烯丙基異氰酸酯 (矽烷耦合劑） IV- 1 : γ-甲基丙烯酸氧丙基Ξ (紫外線吸收劑） V- 1 : 2_羥基_4_正辛氧基二苯丨 (抗氧化劑） 羊細說明本發明。但是， 限定。 物的揮發量（單位：質 Ϊ投入底面之半徑爲1 . 8 以5 0 °C之條件下保管5 原料。 I爲30質量％且MFR ^碳酸酯 ;，3,5-三甲基環己烷 k 丁過氧）己烷 氧基矽烷 酮 -15- 201141930 VI- l :十八烷基-3- ( 3,5-二（三級丁基）-4-羥苯基） 丙酸酯 (光安定劑） VII- 1:雙（2,2,6,6·四甲基-4-哌啶基）癸酸酯 〔實施例1〕 相對於100質量份的EVA-1，添加0.7質量份的.有機 過氧化物1-1、0.5質量份的交聯助劑111-1、0.5質量份的 矽烷耦合劑IV-1、0.1質量份的紫外線吸收劑ν·ΐ、〇」質 量份的抗氧化劑VI-1及0.2質量份的光安定劑VII-1。 接著，使用擠出成形機，於成形溫度1 10°C，成爲0.40 至0.50 mm之厚度的方式來利用擠出法而進行該組成物之 薄片成形。所獲得之封止材薄片之厚度係利用電子測微器 (Anritsu製）而測得。 〔實施例2至3〕 除了如表1所示之方式來變更有機過氧化物1-1之添 加量以外，也進行相同於實施例1之方式而製造封止材薄 片。 〔比較例1至4〕 除了依照表1所示來變更所用之有機過氧化物之種類 與添加量以外，也進行相同於實施例1之方式而製造封止 材薄片。 〔評估方法〕 (初期交聯率） -16- 201141930 使用於實施例及比較例中所製造的封止材薄片，於常 溫常濕之環境中放置6小時後，測定交聯率。交聯率係利 用以下之方法而測得。 從一邊以一大氣壓加壓封止材薄片且一邊於150 °C硬 化1 0分鐘之物，削取少量（0 · 3 g左右）之試樣而測定其 質量（質量W1)。另外，將其試樣於50mL之二甲苯中， 於1 1 0 °C加熱6小時後，測定未溶解物‘之質量（質量W2 )。 將質量W2對質量W1之比（W2/W1 )作爲交聯率（單位： % )。 (保存安定性） 使在實施例及比較例所獲得之封止材薄片與其他薄片 不重疊下設置於溫度40 °C-濕度20% RH之恆溫恆濕槽中之 網狀保管箱內保管48小時。之後，取出該封止材薄片，於 常溫常濕之環境下放置6小時後，利用與以該初期交聯率 所說明的方法相同的方法而測定交聯率。將交聯率爲8 0 % 以上者設爲「〇」，將不足80%者設爲「X」。 (加工時之凝膠的發生） 目視計算在實施例及比較例所獲得之封止材薄片中每 1 m2的凝膠發生數。所計算的凝膠係設定半徑2 mm以上 者。另外，確認面積設爲2 m2。每1 m2之凝膠發生數爲1 個上者設爲「X」、〇個者設爲「〇」。 將在實施例及比較例中之初期交聯率、保存安定性及 加工時之凝膠發生的評估結果顯示於表1。 -17- 201141930 〔表1〕201141930 VI. Description of the Invention: [Technical Field] The present invention relates to a sealing material sheet for a solar cell module and a solar battery module. [Prior Art] In recent years, as a clean power generation technology using sunlight, solar cells are attracting attention. A conventional solar cell module encloses a solar cell unit and seals it in a sealing material layer, and protects the module on both sides of the sealing material layer by a surface protecting member and a back surface protecting member. The solar cell module is manufactured by a method in which a layer is laminated in accordance with a surface protective member, a sealing material sheet, a solar battery cell, a sealing material sheet, and a back surface protective member, and is heated in a vacuum to remove it. After the gas is applied, the solar cell is embedded while applying a load of one atmosphere in a vacuum, and the sealing material resin is cross-linked and hardened to be integrated. In general, as a material of the sealing material sheet, a resin which is a main component is made of EVA (ethylene/vinyl acetate copolymer), and the most common solar cell sealing material sheet is a single layer structure. The organic peroxide is added to the agent (for example, Patent Documents 1 to 5). EVA is crosslinked by the decomposition of organic peroxides by the inclusion of organic peroxides and the generation of free radicals by heat. In this manner, the solar cell unit can be fixed in the sealing material layer of the solar cell module by crosslinking the EVA in accordance with the organic peroxide. Further, in the case of the sealing material sheet, the durability is improved by 201141930, and a crosslinking auxiliary agent, a decane coupling agent, a light stabilizer, and an ultraviolet absorber are often contained in a certain ratio. The method for producing a sealing material sheet is, for example, a T-die method or a calendering method in which a resin which is extruded in a molten state from a die having a linear slit and which is formed into a sealing material sheet by a cooling roll or a water tank is used. The film forming step. By this film forming step, a film of a sealing material having a thickness of about 500 μm is formed. Further, in the film forming step, embossing for imparting unevenness to the surface of the sealing sheet is also carried out. [Prior Art] [Patent Document] Patent Document 1: Japanese Laid-Open Patent Publication No. Hei. No. 2000-183381. [Problems to be Solved by the Invention] However, the conventional seals described in Patent Documents 1 to 5, however, are disclosed in Japanese Laid-Open Patent Publication No. Hei. No. 2005-186233. When the stopper sheet is used after being stored or stored for a certain period of time, the crosslinking ratio of the sealing material layer in the solar cell module is lowered, and the durability of the solar cell module is remarkably lowered. Further, in the production of the sealing material sheet, since gelation occurs in the sheet depending on conditions, it is important to prevent the occurrence of gelation during sheet forming. It is an object of the present invention to provide a sealing material thin film 201141930 for a solar cell module, which can be formed without causing gelation, and can form a high crosslinking ratio even after being used after storage or after storage for a certain period of time. The stopper layer 'is capable of stably producing a high-quality solar battery module having excellent durability. Further, an object of the present invention is to provide a high-quality solar cell module which has excellent durability using a sealing material sheet for a solar cell module. [Means for Solving the Problem] The present invention has the following structure in order to solve the problem: [1] A sealing material sheet for a solar cell module, which comprises a solar cell of an ethylene/vinyl acetate copolymer and an organic peroxide. a sealing material sheet for a module; the organic peroxide is in accordance with the following conditions (A) and (B), and the content of the organic peroxide is 0.4 to 100 parts by mass relative to the ethylene/vinyl acetate copolymer. 1.0 parts by mass. (A) In a cylindrical vessel having a radius of 1.8 cm and a depth of 0.9 cm, the volatile amount of 0.15 g of organic peroxide stored at 50 °C for 5 hours is 15 masses %the following. (B) The organic peroxide is halved in 1 hour at a decomposition temperature of 115 to 140 °C. [2] A solar cell module comprising a solar cell unit, a sealing material layer for sealing the solar cell unit, a surface protective member for protecting a surface side of the sealing material layer, and a back side for protecting the sealing material layer The back surface protective member is formed of the sealing material sheet for a solar cell module according to the above [1]. [Effects of the Invention] 201141930 The sealing material sheet for a solar cell module of the present invention can be formed without causing gelation, and can be formed at a high crosslinking ratio even after being used after transportation or after storage for a certain period of time. The sealing material layer can stably produce a high-quality solar battery module having excellent durability. In addition, the solar cell module of the present invention uses the sealing material sheet for a solar cell module of the present invention, and the sealing material layer having a high crosslinking ratio is stably formed and has excellent durability. High quality. [Embodiment] <Seal-Sheet Sheet for Solar Cell Module> The solar cell module sealing material sheet (hereinafter simply referred to as "sealing material sheet") is used in a solar battery module. The sheet formed by sealing the sealing material layer of the solar cell unit contains an ethylene/vinyl acetate copolymer (EVA) and an organic peroxide. The resin substrate forming the sealing material sheet of the present invention preferably uses EVA as a main component. EVA is highly transparent and inexpensive, especially in the past where performance is so great. The term "EVA as a main component" means that the EVA is 95% by mass or more based on the total amount of the resin substrate. In the sealing material sheet of the present invention, other resins may be contained in addition to EVA. Other resins may, for example, be polyolefins such as polyethylene and polypropylene; ionic polymers; ethylene-methacrylic acid copolymers; ethylene-acrylic acid copolymers; polyvinyl fluoride; polyvinyl chloride, or copolymers thereof. The EVA ratio in the resin base material of the sealing material sheet of the present invention is preferably 201141930 95% by mass or more, more preferably 97% by mass or more, and particularly preferably 100% by mass. The MFR (melt flow rate) of the resin substrate is preferably from 20 to 40 g/l. When the MFR of the resin substrate is a copolymer, it can be adjusted by adjusting the content of the unit derived from the copolymer component. The MFR of EVA can be adjusted by adjusting the content of vinyl acetate units in 100% by mass of EVA. The greedy rate of the vinyl acetate unit in 100% by mass of all units of the EVA is preferably from 20 to 40% by mass, more preferably from 25 to 35% by mass. Further, MFR can also be adjusted by adjusting the molecular weight, and the MFR is made smaller by increasing the molecular weight. The MFR is measured by the method according to ASTM D 1 238. The sealing material sheet of the present invention is characterized in that the crosslinking agent contains an organic peroxide which satisfies the following conditions (A) and (B) (hereinafter, It is called "organic peroxide I"). (A) In a cylindrical vessel having a radius of 1.8 cm and a depth of 〇.9 cm, the volatile amount of 0.15 g of the organic peroxide stored at 50 ° C for 5 hours is 15% by mass. the following. (B) The decomposition temperature of the organic peroxide which is halved in 1 hour is from 1 15 to 140 °C. In the case where a solar cell module is manufactured by using a sealing material sheet after transportation or a sealing material sheet after storage for a certain period of time, the crosslinking ratio of the sealing material layer is lowered. Durability will be significantly reduced by 201141930. In view of the above, the present inventors have found that the organic peroxide contained in the sealing material sheet is volatilized in the sealing material sheet after the transportation or after the storage for a certain period of time. Will be reduced. Therefore, the present inventors have found that by using the organic peroxide I in accordance with the condition (A), the organic peroxide is suppressed from volatilizing from the sealing material sheet, and the sealing material sheet after the transportation or after storage for a certain period of time is used. It is also possible to safely manufacture high quality solar cell modules. Further, the organic peroxide I was reduced in half by one hour to a decomposition temperature of 115 to 140 °C. When the decomposition temperature of the organic peroxide I is 115 °C or more, it is possible to prevent the crosslinking reaction from proceeding during the sheet forming and to cause gelation in the sealing sheet. In addition, when the decomposition temperature of the organic peroxide I is 1400 ° C or less, the crosslinking reaction proceeds sufficiently during the production of the solar cell module, and the crosslinking ratio of the sealing material layer becomes high. A solar cell module with excellent durability is obtained. The organic peroxide I is preferably a tertiary butyl peroxy-2-ethylhexyl monocarbonate (the volatile amount of the condition (A): 7.2 mass%, and the thermal decomposition temperature of the condition (B): 1 19 ° C). The organic peroxide I contained in the sealing material sheet of the present invention is preferably one type. There are two or more kinds of organic peroxides I. Since the volatility of these organic peroxides I is different, it is feared that the ratio of each of the organic peroxides I will change in the sealing material sheet after a certain period of time. And it becomes uneven. However, when the organic peroxide I is one type, even after a certain period of time, it is easy to maintain the uniformity of the organic peroxide 201141930 I in the sealing material sheet, and it is easy to reduce the sun produced by using the sealing material sheet. The characteristics of the pool module are different. In the production of the solar cell module, in the state in which the solar cell is sandwiched by the sealing material sheet, the load is applied while the vacuum is applied, and the sealing material is also applied when the solar cell is embedded. The resin is crosslinked, and the organic peroxide I contained in the two sheets of the sealing material sheets is preferably the same. When the sealing material sheet containing the phase organic peroxide I is used, the amount of the organic peroxide I between the two sheets of the sealing material is almost easily suppressed even after passing through one, and it is easy to reduce the solar energy. The bias of the battery module. The content of the organic peroxide I in the sealing material sheet of the present invention is 0.4 to 1.0 part by mass, preferably 0 0.8 part by mass, per 100 parts by mass of the EVA. When the content of the organic peroxide I is 0.4 parts by mass or more based on the mass part of the EVA, the crosslinking ratio can be formed to be high, and a solar power unit having excellent durability can be produced. When the content of the organic peroxide I is equal to or less than 1 part by mass of the EVA 100 00 mass, it is possible to prevent the gelation from occurring in the sealing material sheet during the crosslinking reaction at the time of sheet formation. Further, in the sealing material sheet of the present invention, in addition to the organic substance, a crosslinking auxiliary agent which promotes a crosslinking reaction may be contained. Crosslinking can be exemplified by triallyl isocyanate, diallyl phthalate, cyanate, and the like. One of the two sheets of energy can be the same as the regular phase of the same phase. The sealing module of 5 to 100 is the oxidizing aid triene-10-201141930. In addition, in the sealing material sheet of the present invention, In the solar cell module, a decane coupling agent may be contained in order to improve the adhesion between the sealing material layer and the surface protective member and the back surface protective member. Examples of the decane coupling agent include γ-methacryloxypropyltrimethoxydecane, trimethoxypropyl decane, trimethoxymethyl decane, ethylene trimethoxy decane, ethylene triethoxy oxime, and trichloroethylene. Propyl decane, triethoxyphenyl decane, and the like. Further, in the sealing material sheet of the present invention, the durability of the formed sealing material layer may be improved, and a stabilizer such as an ultraviolet absorber or an antioxidant may be contained. The ultraviolet absorber used for improving light resistance can be exemplified by 2-(5-methyl-2-hydroxyphenyl)benzotriazole and 2-(3·tris-butyl-5-methyl-2- Hydroxyphenyl)-5-chlorobenzotriazole, 2-(4,6-diphenyl-1,3,5-trit-2-yl)-5-[(hexyl)xyloxy]phenol, 2, 4-dihydroxy-4_benzophenone, 2-hydroxyindole octyloxybenzophenone, and the like. The antioxidant used for improving the thermal stability can be exemplified by 1,6-hexanediol bis[3-(3,5-di(tributyl)-4-hydroxyphenyl)propionate], pentaerythritol. Tetrakis[3-(3,5-di(tri-butyl)-4-hydroxyphenyl)propionate], tris(2,4-di(tri-butyl)phenyl)phosphite, 2, 4-bis(n-octylthio)-6-(4-hydroxy-3,5-di(tri-butyl)anilino)-i,3,5-three wells, eighteen yards-3- (3 , 5- - (secondary butyl) - 4 - - phenyl) propionic acid vinegar and the like. (Manufacturing Method of Sealing Material Sheet) The sealing material sheet of the present invention can be produced by a known production method in addition to the above-mentioned organic peroxy-11-201141930 compound I. For example, a method of forming a film forming step using a τ die or the like by using an organic peroxide and, if necessary, an additive to be added to the resin substrate by heating, may be used. The film formation method of the sealing material sheet is performed by the extrusion method. In the film forming step, in order to prevent agglomeration, the surface of the resin sheet in a state of being thermally melted is bonded to a roll (metal or rubber) on which the uneven pattern has been applied, and the uneven pattern of the roll is transferred. The sealing material sheet is embossed to one side or both sides of the resin sheet. The sealing material sheet of the present invention described above has been inhibited from gelation when the sheet is formed. Further, the amount of the organic peroxide in the sheet is suppressed from being volatilized and reduced in amount after the conveyance or after a certain period of storage. Therefore, in the case of the sealing material sheet of the present invention, the sealing material sheet having a high crosslinking ratio can be stably formed even after a predetermined period of time, and the sealing can be stably produced with high durability. Quality solar cell module. <Solar battery module> The solar battery module of the present invention comprises: a solar battery unit, a sealing material layer for sealing the solar battery unit, a surface protection member for protecting the surface side of the sealing material layer, and the protection A back surface protective member on the back side of the sealing material layer; the sealing material layer is a module formed by the sealing material sheet for a solar cell module of the present invention. Hereinafter, an example of an embodiment of the solar battery module of the present invention will be described in detail. As shown in Fig. 1, the solar cell module 1 of the present embodiment has a solar cell unit 4, 4, a sealing material layer 3 for sealing the solar cell units 4, 4, and a protective sealing material layer. 3 Surface protection member 2 on the front side, and back surface protection member 5 on the back side of the sealing material layer 3. (Solar Cell Unit) The solar cell unit 4 is a unit that converts light incident on the light receiving surface into electricity in accordance with the photoelectric effect. The solar battery unit 4 is housed in the solar battery module 1, and is connected to a plurality of electrodes (two in Fig. 1) by electrodes (omitted from the drawing). The number of solar battery cells 4 is not particularly limited. The material of the solar battery cell 4 can be, for example, a crystal system. Among them, from the viewpoint of ease of manufacture and cost, it is particularly preferred to be polycrystalline. (Sealing material layer) The sealing material layer 3 is a layer in which the solar battery cells 4, 4 are embedded and sealed, and is formed by the sealing material sheet of the present invention. The thickness of the sealing material layer 3 is preferably from 0.3 to 0.6 mm. (Surface protection member) The surface protection member 2 preferably has excellent durability, weather resistance, transparency, and the like. For example, a resin sheet such as a glass plate or polyethylene terephthalate can be used. Further, a resin sheet such as polycarbonate may also be used. The thickness of the surface protection member 2 is preferably from 3 to 6 mm. (Back surface protective member) The back surface protective member 5 is preferably a resin sheet having excellent durability and weather resistance-13-201141930, for example, a resin sheet such as polyethylene terephthalate, polyvinyl fluoride or EVA. And such a layered body. Further, a barrier layer which imparts water vapor barrier properties and oxygen barrier properties may be laminated on the resin sheet or the laminate. The thickness of the back protective member 5 is preferably 0.2 to 0.4 mm. (Manufacturing Method) Hereinafter, a method of manufacturing the solar cell module 1 of the present invention will be described. However, the method of manufacturing the solar cell module of the present invention is not limited by the following methods. As shown in Fig. 2, the layered surface protection member 2, the sealing material sheet 3A, the solar battery unit 4, 4, the sealing material sheet 3B, and the surface protective member 5 are sequentially formed to form a laminated body 1A. Then, the vacuum laminate of the heating and pressure-laden laminate 1A is vacuumed, and the solar cell units 4, 4 are buried in the sealing material sheets 3A and 3B, and the resin substrates (EVA) of the sealing material sheets 3A and 3B are placed. The bonding is hardened and then integrated to form the sealing material layer 3. Thereby, the solar cell module 1 can be obtained. The sealing material sheet 3A and the sealing material sheet 3B are the sealing material sheets of the present invention, and may be a sealing material sheet of the same composition, or may be a sealing material sheet of different composition, by forming a uniform cross-linking structure. From the viewpoint of easily obtaining a module of good quality, a sealing material sheet of the same composition is preferable. Since the solar cell module described above uses the sealing material sheet of the present invention, even if the sealing material sheet is a sealing material sheet after transportation or after storage, the crosslinking ratio of the sealing material layer is also obtained. High quality and excellent durability. -14-201141930 [Examples] Hereinafter, examples and comparative examples are shown. The present invention is based on the following description, and the organic peroxide amount used in the present embodiment is not more than 0.15 g of organic peroxide. In a cylindrical container of cm and depth of 〇.9 cm, the hour is calculated from the mass before and after storage. [Use of Raw Material] The following shows the (EVA) EVA-1 used in the present example: the content of the vinyl acetate unit: EVA of 30 g / 1 minute. (Organic peroxide) I- 1 : Tertiary butyrate-2-ethylhexyl | Π-1 : 1,1_二(三级丁过氧)_ II- 2:2,5-dimethyl -2,5-di(III) (crosslinking aid) ΠΙ-1 : triallyl isocyanate (decane coupling agent) IV-1 : γ-methoxy propyl methacrylate (ultraviolet absorber) V-1 : 2_hydroxy_4_n-octyloxydiphenyl hydrazine (antioxidant) The sheep detail the invention. However, the amount of volatilization of the substance (unit: the radius of the bottom of the enthalpy is 1. 8 at 50 ° C Under the conditions, 5 raw materials are stored. I is 30% by mass and MFR^carbonate; 3,5-trimethylcyclohexane k-butylperoxy)hexaneoxydecane ketone-15- 201141930 VI- l :18 Alkyl-3-(3,5-di(tributyl)-4-hydroxyphenyl)propionate (light stabilizer) VII- 1: bis(2,2,6,6·tetramethyl- 4-piperidinyl) phthalate ester [Example 1] 0.7 parts by mass of the organic peroxide 1-1 and 0.5 part by mass of the crosslinking assistant 111-1 were added to 100 parts by mass of EVA-1. 0.5 parts by mass of decane coupling agent IV-1, 0.1 parts by mass of ultraviolet absorber ν·ΐ, 〇" parts by mass of antioxidant VI-1 and 0.2 parts by mass Stabilizer VII-1 Next, sheet forming of the composition was carried out by an extrusion method at a molding temperature of 10 ° C and a thickness of 0.40 to 0.50 mm using an extrusion molding machine. The thickness of the material sheet was measured by an electronic micrometer (manufactured by Anritsu Co., Ltd.) [Examples 2 to 3] The same was carried out except that the amount of the organic peroxide 1-1 was changed as shown in Table 1. A sealing material sheet was produced in the same manner as in Example 1. [Comparative Examples 1 to 4] The same manner as in Example 1 was carried out except that the type and amount of the organic peroxide used were changed as shown in Table 1. [Production of the sealing material sheet] [Evaluation method] (Initial crosslinking ratio) -16- 201141930 The sealing material sheets produced in the examples and the comparative examples were placed in an environment of normal temperature and humidity for 6 hours, and then measured. Cross-linking rate. The cross-linking ratio was measured by the following method: Pressing the sealing material sheet at a pressure of one atmosphere and hardening it at 150 ° C for 10 minutes, and cutting a small amount (about 0 · 3 g) The mass of the sample was measured (mass W1). Further, the sample was heated in 50 mL of xylene at 110 ° C for 6 hours, and then the mass of the undissolved product '(mass W2 ) was measured. The ratio of the mass W2 to the mass W1 (W2/W1) was taken as Cross-linking ratio (unit: %). (Storage stability) The constant temperature and humidity chamber at a temperature of 40 ° C and a humidity of 20% RH was placed without overlapping the sealing material sheets obtained in the examples and the comparative examples with other sheets. Store in a net storage box for 48 hours. Thereafter, the sealing material sheet was taken out and allowed to stand in an environment of normal temperature and normal humidity for 6 hours, and then the crosslinking ratio was measured by the same method as that described for the initial crosslinking ratio. When the cross-linking rate is 80% or more, it is set to "〇", and when it is less than 80%, it is set to "X". (Generation of gel at the time of processing) The number of occurrences of gel per 1 m 2 in the sealing material sheets obtained in the examples and the comparative examples was visually calculated. The calculated gel system has a radius of 2 mm or more. In addition, the confirmed area is set to 2 m2. The number of gels per 1 m2 is set to "X" for the first one and "〇" for the one. The initial cross-linking ratio, storage stability, and evaluation results of gelation during processing in the examples and comparative examples are shown in Table 1. -17- 201141930 [Table 1]
有機過氧化物 初期交聯率 m 保存安定 性 成形時之 凝膠發生 種類 條件㈧揮發量 [質量％] 條件(Β) 分解溫度 rc] 添加量 [質量份] 保存後之 交聯率[%] 評估 實施例1 1-1 7.2 119 0.7 91.1 89.1 〇 〇 實施例2 Ι·1 7.2 119 0.4 89.8 84.2 〇 〇 實施例3 1-1 7.2 119 1.0 92.4 90.6 〇 〇 比較例1 II-1 12.5 109 0.7 92.2 83.6 〇 X 比較例2 ΙΙ-2 24.9 138 0.7 86.5 70.0 X 〇 比較例3 1-1 7.2 119 0.2 76.6 — — 〇 比較例4 1-1 7.2 119 1.2 93.0 91.9 〇 X 如表1所示，相對於EVA 100質量份，使用0.4至1.0 質量份範圍內之符合條件（A )及條件（B )之有機過氧化 物I的實施例1至3之封止材薄片係初期交聯率高，另外， 它也具有優異的保存安定性。加上，該封止材薄片係於成 形時未發生凝膠而爲高品質。 另一方面，使用條件（B )之分解溫度爲低於1 1 5 °C之 有機過氧化物的比較例1之封止材薄片係於薄片成形時發 生凝膠而使品質變差。 使用條件（A)之揮發量超過15質量％之有機過氧化 物的比較例2之封止材薄片，雖然初期交聯率高，但是保 存後之交聯率大幅降低，保存安定性低。 雖然使用符合條件（A )及條件（B )之有機過氧化物 -18 - 201141930 I，但是其含量相對於EVA 100質量份爲低於0.4質量份之 比較例3的封止材薄片係於保存前之初期狀態下，交聯率 既已低至80%以下。還有，由於該封止材薄片係初期交聯 率不足80質量％，保存後之交聯率也與保存安定性無關而 低於8 0質量％。 雖然使用符合條件（A )及條件（B )之有機過氧化物 I，但是其含量相對於EVA 100質量份爲超過1.0質量份之 比較例4的封止材薄片係於薄片成形時發生凝膠而使品質 變差。 【圖式簡單說明】 第1圖係顯示本發明之太陽能電池模組實施形態之一 例的剖面圖。 第2圖係顯示第1圖之太陽能電池模組製造方法之一 步驟的剖面圖。 【主要元件符號說明】 1 太陽能電池模組 2 表面保護構件 3 封止材層 3 A、3 B 封止材薄片 4 太陽能電池單元 5 背面保護構件 -19-Initial crosslinking rate of organic peroxides m Preservation type conditions for gel formation during stability forming (8) Volatilization amount [% by mass] Conditions (Β) Decomposition temperature rc] Addition amount [parts by mass] Crosslinking ratio after storage [%] Evaluation Example 1 1-1 7.2 119 0.7 91.1 89.1 〇〇 Example 2 Ι·1 7.2 119 0.4 89.8 84.2 〇〇 Example 3 1-1 7.2 119 1.0 92.4 90.6 〇〇Comparative Example 1 II-1 12.5 109 0.7 92.2 83.6 〇X Comparative Example 2 ΙΙ-2 24.9 138 0.7 86.5 70.0 X 〇Comparative Example 3 1-1 7.2 119 0.2 76.6 — — 〇Comparative Example 4 1-1 7.2 119 1.2 93.0 91.9 〇X As shown in Table 1, 100 parts by mass of EVA, the sealing materials of Examples 1 to 3 which are in accordance with the conditions (A) and (B) of the organic peroxide I in the range of 0.4 to 1.0 parts by mass are high in initial crosslinking ratio, and It also has excellent preservation stability. In addition, the sealing material sheet is high in quality when no gel is formed during molding. On the other hand, the sealing material sheet of Comparative Example 1 using the organic peroxide having a decomposition temperature of less than 1 15 °C under the condition (B) was gelled at the time of sheet formation to deteriorate the quality. In the sealing material sheet of Comparative Example 2, which uses the organic peroxide having a volatile content of more than 15% by mass in the condition (A), the initial crosslinking ratio is high, but the crosslinking ratio after storage is largely lowered, and the storage stability is low. Although the organic peroxide -18 - 201141930 I which satisfies the conditions (A) and (B) is used, the content of the sealing material of Comparative Example 3 is less than 0.4 parts by mass relative to 100 parts by mass of the EVA. In the initial state, the cross-linking rate was as low as 80% or less. In addition, since the initial crosslinking ratio of the sealing material sheet is less than 80% by mass, the crosslinking ratio after storage is also less than 80% by mass irrespective of storage stability. Although the organic peroxide I which satisfies the conditions (A) and (B) is used, the content of the sealing material of Comparative Example 4 is more than 1.0 part by mass relative to 100 parts by mass of the EVA, and the gel is formed at the time of sheet formation. And the quality is worse. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a cross-sectional view showing an example of an embodiment of a solar battery module of the present invention. Fig. 2 is a cross-sectional view showing a step of manufacturing a solar cell module of Fig. 1. [Main component symbol description] 1 Solar battery module 2 Surface protection member 3 Sealing material layer 3 A, 3 B Sealing material sheet 4 Solar battery unit 5 Back protection member -19-