200918635 九、發明說明： 【發明所屬之技術領域】 本發明係關於兩面黏著片，更詳細而言，係關於 生量少且具有高黏著物性，而可用於固定除去存在 發光（以下，簡稱爲EL)元件之內部空間且對該EL 造成不良影響之氣體成分的除去構件的兩面黏著片 【先前技術】 將電場施加於物質時產生發光現象.謂之電致發光 象’此爲人所熟知。EL元件爲利用此等EL現象者 元件之一種的有機EL元件，具有將至少一層有機發 持於一對電極間而成的積層體，其藉由從上述積層 電極注入的電子與從另一電極注入的電洞在有機發 結合而發光。使用此等有機EL元件的顯示器，使顢 高對比、低電力消耗及薄型化成爲可能，且具有所 用溫度領域廣」之優於先前薄型顯示器的機能。 但是，上述有機EL元件，具有隨著高溫條件下的 一定期間的使用，發光亮度及發光均一性等發光性 期顯著差的缺點。此等發光性能變差的一原因，可 發光部分（黑點）的產生。已知此等黑點係因水分、 有機系氣體侵入上述積層體的陰極表面部分等，引 發光層與陰極間的剝離或陰極表面的氧化，以致變 電而產生。然後，爲該原因的水分、氧氣或有機系 係因例如存在於元件內部的氛圍氣體、從外部侵入 部的氣體或者吸著於構成零件或構成材料的氣體脫 生，其接觸上述積層體，造成黑點的產生。 外氣產 於電致 元件會 (EL)現 。爲EL 光層挾 體的一 光層內 ,角廣、 謂「使 使用及 能比初 歹！]舉不 氧氣或 起有機 成不通 氣體， 元件內 離而產 200918635 關於具有除去存在於該EL元件內部氛圍氣體之水分之 材料的有機EL元件，例如’已提出在部分地具有由多孔質 材料構成之區域的容器內收藏除去指定氣體成分之除去劑 的E L元件用構件（例如，參照專利文獻1)。 又提出使用通氣性片材’且爲了使有機物氣體不易自接 著劑放出’而使接著劑之凝膠分率成爲7〇%以上的固定構 件（例如，參照專利文獻2)。 再者’關於具有除去上述氣體成分之除去劑的片材，例 如’已提出在具有氣體透過性的母材薄膜中分散有除去指 定氣體成分之粉粒狀除去劑的氣體成分處理片（例如，參照 專利文獻3)。 另一方面，關於固定於封裝框體用的除去片，例如，已 提出具備除去指定氣體成分之除去劑，以及被固定於該除 去劑且使該除去劑接著於EL元件內面之接著構件的除去 片（例如’參照專利文獻4)。 不過’在上述所有提案中，對於用於固定除去劑於元件 內的材料’雖記載有感壓黏著劑等，但此等僅係一般公知 的黏著劑材料；對於抑制對發光性能有不良影響之有機氣 體（外氣）產生的成分及組成則無記載。 再者’由於要求EL元件的薄型化，所以期望所用的兩面 黏著片進一步薄膜化。 專利文獻1 :日本專利第3447 65 3號公報 專利文獻2 :日本專利第3 5 5 8 5 7 8號公報 專利文獻3:日本專利申請案公開2001-278999號公報 專利文獻4 :日本專利申請案公開2 0 0 1 - 3 4 5 1 7 3號公報 200918635 【發明內容】 發明所欲解決的課題 本發明係以提供在此等狀況下外氣產生量少且具有胃@ 著物性，而可用於固定除去存在於EL元件之內部空間且對 該EL元件會造成不良影響之氣體成分的除去構件的 黏著片爲目的。 解決課題的手段 本發明者，爲了達成上述目的反覆用心硏究，結果發現 藉由使用含有醋部分具有低碳數院基之（甲基）丙嫌酸院 酯單位及含反應性官能基之乙烯性不飽和單體單位的不含 羧基之丙烯酸系共聚物之交聯物，作爲構成兩面黏著片之 黏著劑層的黏著劑，可以達成該目的。本發明基於該發現 而完成。 亦即，本發明提供： (1) 一種兩面黏著片’其係用於固定除去存在於電致發光 (EL)元件內部空間的指定氣體成分的除去構件之兩面黏著 片’其特徵爲在基材片的兩面上具有黏著劑層，構成各黏 著劑層之黏著劑爲含有不含羧基之丙烯酸系共聚物的交聯 物’其中該不含羧基之丙烯酸系共聚物含有：（幻烷基的碳 數爲4以下之（甲基）丙烯酸烷酯單位，及（Β)含反應性官能 基之乙烯性不飽和單體單位； (2) 如上述（1)記載之兩面黏著片，其中不含羧基之丙烯酸 系共聚物中（Α)單位與（Β)單位之含有比率，以質量比計， 爲 95 : 5 至 99.5 : 0.5 ; (3) 如上述（1)記載之兩面黏著片，其中不含羧基之丙烯酸 200918635 系共聚物進一步含有（c)含乙烯性不飽和基的嗎啉系化合 物單位； (4) 如上述（3)記載之兩面黏著片，其中相對於（A)單位與（B) 單位之合計量100質量份，（C)單位之含量爲2~30質量份； (5) 如上述（1)記載之兩面黏著片，其中（B)含反應性官能基 之乙烯性不飽和單體單位爲含羥基之乙烯性不飽和單體單 位； (6) 如上述（1)記載之兩面黏著片，其中於1 2 〇 °C之溫度加熱 10分鐘時外氣產生量以正癸烷換算量計爲低於〇.5 " g/cm2 ； (7) 如上述（1)記載之兩面黏著片，其中黏著劑層的厚度，2 層合計爲25/zm以下； (8) 如上述（1)記載之兩面黏著片，其中從一面的黏著劑層 至另一面的黏著劑層’形成孔徑爲20〜200/zm,孔密度爲 30~10,000 個 /10 cm2 的貫穿孔。 發明之效果. 根據本發明，可以提供外氣產生量少且具有高黏著物 性’而可用於固定除去存在於EL元件之內部空間之指定的 氣體成分，即對該EL元件會造成不良影響之氣體成分的除 去構件的兩面黏著片。 【實施方式】 本發明的兩面黏著片係用於固定除去存在於EL元件內 部S間的指定氣體$ β @卩余$構件，其使用形態依照隨附 的圖式說明。 元件1，係在平板狀 第1圖爲EL元件之模式剖面圖。Elj 200918635 之基板2上形成以陽極8及陰極6挟持有機發光層？而成 之積層體（EL積層體）5，在上述基板2上以覆蓋該積層體$ 之方式設置㈣框H 3,且該封裝框體3之周緣部與上述 基板2藉由封裝材肖4固定者。而且，在上述封裝框體3 之頂—棚藉兩面黏著片1Q固定除去構件9。㈣，成爲侵入 EL兀件1內部之黑點之原因的水分、有機氣體等氣體成 分’藉由除去構件9除去。 又，在第1圖中，除去構件9雖被固定於封裝框體3的 頂棚，但對於其固定位置並無特別限定，例如固定於封裝 框體3的側壁亦可。 第2圖爲本發明的兩面黏著片的一例的剖面圖，兩面黏 著片1 0係作成於基材片1 1的兩面設置黏著劑層1 2及} 3 的構造。 在本發明中對於除去構件沒有特殊限制，可以從除去成 爲黑點原因之氣體成分所使用的除去構件中，在先前 元件中’適當選擇任一者而使用。就此等除去構件而言， 可列舉在透氣性塑膠片中分散吸著劑、吸濕劑（乾燥劑）、 脫氧劑等除去劑而成之片狀物或將除去劑收納於通氣性容 器而成者等。 [基材片] 本發明的兩面黏著片中之基材片，若爲難以產生有機氣 體者即可，無特殊限制，可以使用各種各樣者。具體而言， 可列舉聚乙烯、聚丙烯等聚烯烴，聚對苯二甲酸乙二酯、 聚對苯二甲酸伸丁酯等聚酯，聚醯亞胺、聚醯胺等樹脂製 的片材，並於此等片材上施行鋁等的金屬蒸鍍者；合成紙' 200918635 含浸紙等所構成的紙類；鋁箔或銅箔等金屬箔等。 對於此等基材片的厚度沒有特殊限制，惟通常在約2~50 // m的範圍’從薄膜化的面向而言，較佳在約3〜2〇 v m的 範圍內。 在使用樹脂製片材作爲基材片之情況，爲了使與設於其 上的黏著劑層的接著性提高，可以進行氧化法或凹凸化法 等表面處理。就上述氧化法而言，可列舉例如電暈放電處 理、鉻酸處理（濕式）、火焰處理、熱風處理、臭氧.紫外 線照射處理等；再者，就凹凸化法而言，可列舉例如噴沙 法、溶劑處理法等。此等表面處理法，雖可視基材片的種 類而適當選擇，但從效果及操作性等方面而言，一般以使 用電暈放電處理法爲較佳。再者，可以施行設置電槳層之 電漿處理。 [黏著劑層] 設於上述基材片之兩面之各黏著劑層，在本發明中係以 由含有不含羧基之丙烯酸系共聚物的交聯物的黏著劑所構 成爲特徵，其中該不含羧基之丙烯酸系共聚物含有：（A)烷 基的碳數爲4以下之（甲基）丙烯酸烷酯單位、（B)含反應性 官能基之乙烯性不飽和單體單位、及視需要可存在的（C)含 乙烯性不飽和基之嗎啉系化合物單位。若使用含羧基之丙 烯酸系共聚物所構成之黏著劑，則丙烯酸酯單體之側鏈部 位，於丙烯酸或甲基丙烯酸等羧基存在下，會因熱及溼度 而分解，其分解物將以外氣形式產生。 (單體） 形成爲上述（A)單位之烷基的碳數爲4以下之（甲基）丙烯 -10- 200918635 酸烷酯單位的單體，具體而言，可列舉（甲基）丙烯酸甲酯、 (甲基）丙烯酸乙酯、（甲基）丙烯酸正丙酯、（甲基）丙烯酸異 丙酯、（甲基）丙烯酸正丁酯、（甲基）丙烯酸異丁酯、（甲基） 丙烯酸第二丁酯、（甲基）丙烯酸第三丁酯等。 其中’從與黏性、凝集力之平衡，以及降低聚合後之殘 留單體、側鏈分解物之沸點，黏著劑塗布時藉由熱乾燥之 揮發份去除的觀點而言，以使用（甲基）丙烯酸正丁酯或（甲 基）丙烯酸甲酯爲較佳。此等可以一種單獨使用，亦可將兩 r 種以上組合使用。 烷基的碳數超過4之（甲基）丙烯酸烷酯，會使下述外氣產 生量變多，而無法達成本發明的上述目的。 形成上述（B)單位之含反應性官能基之乙烯性不飽和單體 中的反應性官能基，爲交聯化時可與異氰酸酯等反應的羥 基或醯胺基等基，因此可以使用係屬不含羧基之單體且含 羥基或醯胺基的乙烯性不飽和單體作爲含反應性官能基之 乙烯性不飽和單體。 / ： 就含羥基之乙烯性不飽和單體而言，可列舉（甲基）丙烯酸 羥烷酯類，例如（甲基）丙烯酸2 -羥基乙酯、（甲基）丙烯酸 2-羥基丙酯、（甲基）丙烯酸3-羥基丙酯、（甲基）丙烯酸2_ 羥基丁酯、（甲基）丙烯酸3 -羥基丁酯、（甲基）丙烯酸4 -羥 基丁酯等。 就含醯胺基之乙烯性不飽和單體而言，可列舉例如丙儲 醯胺、N，N -二甲基丙烯醯胺、Ν，Ν·二甲基甲基丙烯醯胺、 Ν -經甲基丙烯醯胺、Ν -羥甲基甲基丙烯醯胺等丙烯醯胺系 單體等。 -11 - 200918635 此等含反應性官能基之乙烯性不飽和單體，可使用一 種，亦可將二種以上組合使用，但在含醯胺基之乙烯性不 飽和單體的情況，過剩量之添加會提高共聚物的Tg，引起 濕潤性的降低，結果無法得到充分的黏著力，而難以適用 於本發明。因此，使用時以盡量少用爲較佳。 在本發明中，形成（B)單位之單體，從可賦予不會因熱而 變色的丙烯酸系共聚物的觀點而言，以使用含羥基之乙烯 性不飽和單體爲較佳。 在本發明中，不可將如（甲基）丙烯酸單位之乙烯性不飽和 羧酸單位導入丙烯酸系共聚物中，作爲係（B)單位之含反應 性官能基之乙烯性不飽和單體單位，藉此可以得到側鏈完 全不含羧基的丙嫌酸系共聚物。具有由含該丙烯酸系共聚 物之黏著劑所構成之黏著劑層的兩面黏著片，外氣產生量 少，而可用於固定除去存在於EL元件之內部空間且對該 EL元件會造成不良影響之氣體成分的除去構件。 在本發明中，於不含羧基之丙烯酸系共聚物中，上述（A) 單位與（B)單位之含有比，從黏著劑之凝集力與黏著力之平 衡之觀點而言，以質量比計較佳爲95 : 5〜99.5 : 0.5 ,更佳 爲 96 : 4〜99 : 1 。 本發明中不含羧基之丙烯酸系共聚物，從黏著力與黏性 之平衡的觀點而言’較佳含有作爲（C)單位之含乙烯性不飽 和基之嗎啉系化合物單位。就形成該（C)單位之嗎啉系單體 而言，可使用例如N -乙烯基嗎啉、N -烯丙基嗎啉、N -(甲基） 丙烯醯基嗎啉等。該嗎啉系單體，可單獨使用一種，亦可 將二種以上組合使用。 -12- 200918635 其中，從形成上述（A)單位之單體與形成（B)單位之單體的 共聚性良好的觀點而言，以N-(甲基）丙烯醯基嗎啉爲較佳。 在本發明中’該（C)單位之含量，從黏著劑之黏著力與黏 性之平衡的觀點而言，相對於上述（A)單位與（B)單位的合 計量100質量份，以2~30質量份爲較佳，以4~25質量份 爲更佳。 在本發明的兩面黏著片中，形成黏著劑層之丙烯酸系共 聚物中之上述（C)單位組入共聚物，而於側鏈含有嗎啉構 造，其在藉由下述異氰酸酯系交聯劑進行的交聯反應中具 有交聯促進劑的角色，由於可在未添加向來使用的低分子 量交聯促進劑下得到必要的黏著劑物性，所以不會產生起 因於低分子量物的外氣。 在本發明中，於上述丙烯酸系共聚物中，視需要可添加 於聚合時作爲（D)形成其他單位之乙烯性不飽和單體的苯 乙烯、乙酸乙烯酯、含乙烯性不飽和基之咪唑系化合物、（甲 基）丙烯腈等形成上述（A) ~ (C)單位之乙烯性不飽和單體以 外的不含羧基之乙烯性不飽和單體。 該不含羧基之丙烯酸系共聚物中上述（D)單位之含量，從 黏著劑之黏性與黏著力之平衡的觀點而言，相對於上述（A) 單位與（B)單位的合計量1〇〇質量份’以0〜1〇質量份爲較 佳，以〇〜5質量份爲更佳。 (丙烯酸系共聚物的製造） 在本發明中，黏著劑所用的丙烯酸系共聚物較佳藉由將 上述各單體溶解於，例如’如甲苯或二甲苯之烴系或如乙 酸乙酯之酯系等有機溶劑中後’添加先前公知的偶氮雙異 -13- 200918635 丁腈、2,2’ -偶氮雙（2-脒基丙烷）二鹽酸鹽、4,4，—偶氮雙 (4-氰基纈草酸）等偶氮系聚合起始劑或苄醯基過氧化物等 過氧化物系聚合起始劑進行自由基聚合反應而製造。 上述聚合起始劑的量’相對於單體總量1 〇 〇質量份，較 佳在0_01〜5質量份的範圍內，特佳在質量份的範圍 內。 在聚合反應中’隨著聚合的進行聚合系統中單體及聚合 起始劑逐漸減少，在聚合後期由於兩者相遇的機率變得非 常低’所以單體會殘存在系統中。殘存的單體，由於一則 爲黏著片異臭的原因’再則多爲具有刺激性及毒性的化合 物’所以殘存於黏著劑中將不佳。微量的（爲饋入之單體的 數％以下）殘存單體從聚合物中之分離，從能量經濟性的觀 點而言不佳。因此，在聚合快要終了時，通常採取在系統 內添加被稱爲追加劑的後續添加聚合起始劑，儘量使該殘 存單體聚合而減低殘存單體的手法。 自由基聚合’通常藉由於約l〇~l〇〇°C，較佳於約50〜90 °C，加熱約1〜2 〇小時，較佳約3〜1 0小時，得到丙烯酸系 共聚物的有機溶劑溶液。 所得到之不含羧基的丙烯酸系共聚物的重量平均分子 量，通常爲20萬以上’較佳爲40萬〜200萬，更佳爲50 萬〜100萬。 關於高分子量化手法有：選擇難以進行鏈轉移者作爲溶 劑，提高反應液中單體混合物的濃度（爲了防止鏈轉移至溶 劑而降低溶劑濃度）、減低聚合起始劑的濃度（相對於單 體），於較低反應溫度進行聚合等方法，藉由組合此等進行 -14- 200918635 聚合可以得到具有如上述重量平均分子量的不含羧基之丙 烯酸系共聚物。 再者’上述重量平均分子量係藉由透膠層析（GPC)法測定 之聚苯乙烯換算値。 在本發明中，該不含羧基之丙烯酸系共聚物可單獨使用 一種，亦可將兩種以上組合使用。 (交聯劑） 在本發明中’構成黏著劑層的黏著劑係含有上述不含羧 ( 基之丙烯酸系共聚物的交聯物以作爲樹脂成分者，用於得 到該交聯物的交聯劑較佳爲聚異氰酸酯系交聯劑。 聚異氰酸酯系交聯劑爲分子內具有2個以上異氰酸酯基 的化合物，具體而言，可列舉甲苯二異氰酸酯（TDI)、四亞 甲基二異氰酸酯、六亞甲基二異氰酸酯（HMDI)、異佛爾酮 二異氰酸酯（IPDI)、二甲苯二異氰酸酯（XDI)、氫化甲苯二 異氰酸酯、二苯基甲烷二異氰酸酯、經氫化之二苯基甲烷 二異氰酸酯、以及將此等與三羥甲基丙烷等進行加成反應 ς 而得之聚異氰酸酯化合物或異氰脲酸化物、縮二脲型化合 物；再者，與公知的聚醚多元醇或聚酯多元醇、丙烯酸系 多元醇、聚丁二烯多元醇、聚異戊二烯多元醇等進行加成 反應而得的胺基甲酸酯預聚物型聚異氰酸酯等。 此等交聯劑，可單獨使用一種，亦可將二種以上組合使 用。 交聯劑的使用量，相對於不含羧基的丙烯酸系共聚物100 質量份，宜爲約0.1 ~ 1 0質量份，藉由調整該交聯劑的使用 量，可調製永久接著型或再剝離型黏著劑。 -15- 200918635 (黏著劑層的形成） 本發明的兩面黏著片爲基材片的兩面具有黏著劑 該黏著劑層，例如，可藉由以下的方法製作。 首先，調製含有上述不含羧基之丙烯酸系共聚物 交膠聯劑及視需要使用的溶劑或各種添加劑的黏著 液。關於上述各種添加劑，只要在不損及本發明目 圍內，可適當地使用氧化防止劑、紫外線吸收劑、 與劑、光安定劑及充塡劑等。再者，關於溶劑，可 的丙烯酸系黏著劑塗布液所使用者中適當地選擇來/ 接下來，將上述黏著劑塗布液藉由先前公知的方 如旋塗法、噴塗法、棒塗法、刀塗法、輥塗法、刮刀 模頭塗法、凹版塗法等方法塗布於剝離層的剝離層 爲了防止溶劑及低沸點成分的殘留，於約80〜150°C 加熱約3 0秒至5分鐘，製作成2片附有黏著劑層的泰 藉由將該黏著劑層貼附於基材片的兩面而彼此相對 得到目的之兩面黏著片。再者，剝離片，爲了保護 層，通常於使用前爲貼附的狀態。又，與上述同樣 上述黏著劑塗布液直接塗布於基材片的兩面並加熱 形成黏著劑層，在其上爲了保護可貼附剝離片。 對於如此形成的黏著劑層的厚度沒有特殊限制， 地選定，惟就單面的黏著劑層而言，通常在2~30μ 圍內，較佳在3〜20#111的範圍內選擇。再者，EL元 近年要求薄膜化的觀點而言，以兩層合計在25# m 更佳。 [剝離片] 層者， 、上述 劑塗布 的之範 黏著賦 從通常 丨吏用。 法，例 塗法、 面後， 的溫度 :|J離片， ，可以 黏著劑 地，將 處理， 可適當 m的範 件，從 以下爲 -16 - 200918635 就上述剝離片而言’可列舉在，例如，玻璃紙、塗布紙、 局級紙寺紙基材’於此等紙基材上積層聚乙烧或聚丙燦等 熱可塑性樹心而成之積層紙，於上述基材上用纖維素、澱 粉、聚乙烯醇、丙烯酸系-苯乙烯樹脂等進行塡縫處理而成 的紙基材’或如聚對苯二甲酸乙二酯、聚對苯二甲酸丁二 酯、聚萘二甲酸乙二酯等聚酯薄膜，如聚乙烯或聚丙烯等 聚烯烴薄膜之塑膠薄膜，及在此等塑膠薄膜上施行易接著 處理而成的薄膜等上，塗布剝離劑者等。 就用於形成剝離劑層的剝離劑而言，可使用，例如，烯 烴系樹脂、異戊二烯系樹脂、丁二烯系樹脂等樹膠系彈性 體、長鏈烷基系樹脂、醇酸系樹脂、氟系樹脂、聚矽氧系 樹脂。 在基材上所形成的剝離劑層的厚度，雖無特殊限定，但 在以溶液狀態塗布剝離劑的情況，以0.05~2.0 // m爲較佳， 以0.1〜1.5/zm爲更佳。 在使用聚乙烯或聚丙烯等熱可塑性樹脂形成剝離劑層的 情況，剝離劑層的厚度以3〜50μ m爲較佳，以5〜40// m爲 更佳。 [兩面黏著片] 如上述製造的本發明兩面黏著片以外氣產生量少爲特 徵。在本發明中，外氣產生量以正癸烷換算値來比較。 藉由來自黏著劑層之外氣產生量以正癸烷換算値計未達 0.5 # g/cm2，可以減少黑點產生。 本發明的兩面黏著片’於120 °C之溫度加熱10分鐘時的 產生氣體量（A)，以正癸烷換算値計，未達〇.5 " g/cm2 ’更 -17- 200918635 佳在0.1 /z g/cm2以下’而且由於不會腐蝕被著體，所以適 於EL元件的長壽命化。 再者，上述產生氣體量爲剝離除去上述剝離片下測定的 値。再者，對於具體的產生氣體的測定方法，將在實施例 中詳細說明。 若基材片變薄，則將在一側表面貼著除去構件的兩面黏 著片貼附於封裝框體之時，在黏著劑層與封裝框體之間以 嵌合狀態貼附空氣，而成爲黏著力低的原因。爲了防止該 / 現象，從一側的黏著劑層至另一側的黏著劑層，較佳形成 孔徑爲約20〜200# m，孔密度爲30〜10,000個/10cm2的貫通 孔。 藉此，黏著劑層與封裝框體之間的空氣，由於通過貫通 孔移動至相反表面，進一步通過具有通氣性的除去構件而 釋出，所以可防止空氣成爲嵌合的狀態。 對於貫通孔的橫斷面形狀雖無特殊限定，貫通孔在基材 片及黏著劑層中的孔爲約2 0 ~ 2 0 0 // m，較佳爲5 0〜1 5 0 // m。 . 貫通孔的孔徑若爲20 /z m以上，空氣或氣體容易消除；貫 通孔的孔徑若爲200 // m以下，黏著力良好。 貫通孔的孔密度爲約30~ 10,000個/l〇cm2，較佳爲 50~5,000個/10cm2。貫通孔的孔密度若爲30個/10cm2以上， 則空氣或氣體容易消除；貫通孔的孔密度若爲1 0,000個 /10cm2以下，則兩面黏著片的機械強度良好。 上述貫通孔，以藉由雷射加工形成爲較佳。若藉由雷射 加工，容易以期望的孔密度形成空氣消除性良好的微細貫 通孔。 -18- 200918635 對於雷射加工所利用的雷射的種類沒有特殊限定，可以 利用，例如，二氧化碳（CCh)雷射、TEA-CCh雷射、YAG雷 射、UV-YAG雷射、準分子雷射、半導體雷射、YV〇4雷射、 YLF雷射等。 第3圖爲顯示在本發明的兩面黏著片中，從一側的黏著 劑層至另一層的黏著劑層貫通孔被形成的狀態的斷面圖。 圖中符號11爲基材片，12、13爲黏著劑層及14爲貫通孔。 實施例 r 以下，藉由實施例進一步詳細地說明本發明，但本發明 \ 不限於此等實施例。 再者，各例所得之兩面黏著片之性能評價方法示於下文。 (1) 黏著力 將兩側具有剝離片之兩面黏著片，在2 3 °C、5 0 % R Η環境 下’除去單側的剝離片，將露出的黏著劑層貼合於厚度25 // m的聚對苯二甲酸乙二酯薄膜，同時除去另一側的剝離 片，將露出的黏著劑層接著於不銹鋼板，依照Π S Z 0 2 3 7 ^ 於貼附2 4小時後’進行1 8 0度剝開並測定黏著力（n / 2 5 m m)。 (2) 外氣產生量 將試料（2 0 c m2)封入安瓿瓶中’將該安瓿瓶在吹掃補集氣 相層析質譜儀（GC Mass)[日本電子工業股份有限公司製， 「JHS-100A」]中’於120°C加熱10分鐘，採取氣體，之後 將其導入 GCMass(PERKINELMER 製，「TurboMass」），從 使用正癸烷作成的檢量線求出以正癸烷換算量（μ g/cm2)表 示之氣體產生量。 再者’在各例中之重量平均分子量意指藉由透膠層析 -19- 200918635 (GPC)法所測得之換算成聚苯乙烯的重量平均分子量。 實施例1 (1) 黏著劑組成物溶液的調製 將由爲（A)成分之丙烯酸正丁酯97.4質量份、丙烯酸甲酯 2.0質量份與爲（B)成分之丙烯酸2-羥基乙酯0.6質量份所 構成的混合物，作爲聚合起始劑之偶氮雙異丁腈〇 . 1質量 份，作爲溶劑之乙酸乙酯1 5 0質量份置入反應器中，於攪 拌下升溫至80~90°C並進行聚合反應，然後逐次添加偶氮雙 異丁腈0.1質量份溶於甲苯10質量份而成的聚合觸媒液， 同時進行聚合計7小時。反應終了後，藉由追加稀釋溶劑（甲 苯與乙酸乙酯的混合溶劑），製造重量平均分子量爲50萬 的不含羧基之丙烯酸系共聚物之40質量％溶液。 在該丙烯酸系共聚物溶液100質量份（固形份爲40質量份） 中加入甲苯二異氰酸酯（TDI)系交聯劑（「Coronate L55E」’ 日本聚胺基甲酸酯公司製，固形份55質量％ )1質量份，調 製成黏著劑組成物溶液。 (2) 兩面黏著片之製作 使用單面經剝離處理且厚度爲3 8 // m的聚對苯二甲酸乙 二酯薄膜[三菱聚酯薄膜股份有限公司製「T1 00」]作爲剝 離片，將上述（1)所得之黏著劑組成物溶液以使乾燥後之厚 度成爲9 # m的方式塗布於剝離處理面後，於1 2 0 °C乾燥2 分鐘，形成黏著劑層。接下來，將作爲基材片之厚度爲12 //m的聚對苯二甲酸乙二酯（PET)薄膜[東麗公司製「S10」] 貼附於黏著劑層面，製作成單面黏著片。 再者，將黏著劑組成物溶液以使乾燥後之厚度成爲9以m -20- 200918635 的同樣操作方式積層於另一經剝離處理的聚對苯二甲酸乙 二酯薄膜（前出）上，將先前製成的單面黏著片的PET薄膜 (厚度：1 2 /z m)面貼合於黏著劑組成物表面，製成兩面黏著 片。 將該兩面黏著片的性能示於表1中。 實施例2 (1) 黏著劑組成物溶液的調製 除使用由爲（A)成分之丙烯酸正丁酯79.0質量份、丙烯酸 ζ ' 甲酯2.0質量份，爲（Β)成分之丙烯酸2-羥基乙酯2.0質量 份及爲（C)成分的Ν-丙烯醯基嗎啉17.0質量份所構成的混 合物，代替由爲（Α)成分之丙烯酸正丁酯97.4質量份、丙烯 酸甲酯2.0質量份與爲（Β)成分之丙烯酸2-羥基乙酯0.6質 量份所構成的混合物之外’與實施例1之[(1)黏著劑組成物 溶液的調製]完全同樣地實施，調製成黏著劑組成物溶液。 (2) 兩面黏著片的製作 除使用上述（1)所得之黏著劑組成物溶液之外，與實施例 r 1之[(2)兩面黏著片的製作]完全同樣地實施，製作成兩面 k 黏著片。 該兩面黏著片的性能示於表1中。 實施例3、4及比較例1、2 使用表1所示種類及量的共聚物成分’與實施例1同樣 地調製黏著劑組成物溶液，然後製作兩面黏著片。 各兩面黏著片的性能示於表1中。 實施例5 使用厚度6.3# m的聚對苯二甲酸乙一醋[東麗公司製 -21 - 200918635 「F53」]作爲基材片，且除了黏著劑層厚度（單面4am，單 面4 // m)之外，與實施例2同樣地製作兩面黏著片。 在所製作之兩面貼附有剝離片的兩面黏著片上，用二氧 化碳雷射形成口徑50/zm、孔密度爲200個/10cm2的貫通 孔，而製作成具有貫通孔的兩面黏著片。 該兩面黏著片的性能示於表丨中。 表1 實施例 比較例 1 2 3 4 5 2 丙烯酸 系共聚 物的各 單位(質 量％) 丙烯酸丁酯(A) 97.4 79.0 61.0 93.0 79.0 94.0 丙烯酸甲酯(A) 2.0 2.0 20.0 2.0 _ 2.0 丙烯酸2-乙基己 酯 93.0 丙烯酸2-羥基乙 酯(B) 0.6 2.0 2.0 2.0 2.0 2.0 2.0 丙烯酸 2.0 N-丙烯醯基嗎啉 17.0 17.0 5.0 17.0 5.0 黏著力(N/25mm) 5.13 7.13 6.50 5.30 4.50 6.25 5.50 外氣產生量(#g/cm2) 0.04 0.04 0.04 0.04 0.03 0.77 0.65 從上述結果可以確認實施例所得之黏著片顯示高黏著 力。再者，在外氣產生方面，確認產生量十分低。又，縱 使如在實施例5所見到之基材片薄且整體亦薄的兩面黏著 片，藉由設置貫通孔，可在未抽真空下，而容易地貼附於 被著體。 另一方面，在使用烷基的碳數超過4者及丙烯酸的比較 -22- 200918635 例中外氣產生量多。 產業上的可利用性 本發明的兩面黏著片，外氣產生量少且具有高黏著物 性’可用於固定除去存在於el元件之內部空間且對該EL 元件會造成不良影響之氣體成分的除去構件。 【圖式簡單說明】 [第1圖]爲E L元件之模式剖面圖。 [第2圖]爲本發明的兩面黏著片的一例的剖面圖。 [第3圖]爲顯示本發明之兩面黏著片中，從一面的黏著劑 層至另一面的黏著劑層形成貫通孔之狀態的剖面圖。 【主要元件符號說明】 1 EL元件 2 基板 3 封裝框體 4 密封材料 5 EL積層體 6 陰極 7 有機發光層 8 陽極 9 除去構件 10 兩面黏著片 11 基材片 12 黏著劑層 13 黏著劑層 14 貫通孔 -23-200918635 IX. OBJECTS OF THE INVENTION: 1. Field of the Invention The present invention relates to a double-sided adhesive sheet, and more particularly to a low amount of raw material and a high adhesive property, and can be used for fixing and removing the presence of light (hereinafter, simply referred to as EL A double-sided adhesive sheet of a removal member of a gas component which has an internal space of the element and adversely affects the EL. [Prior Art] An electroluminescence phenomenon is produced when an electric field is applied to a substance. This is known as electroluminescence. The EL element is an organic EL element which is one of the elements of the EL phenomenon, and has a laminate in which at least one layer is organically held between a pair of electrodes, and the electrons injected from the laminated electrode and the other electrode The injected holes are combined in the organic hair to emit light. The display using these organic EL elements makes it possible to achieve high contrast, low power consumption, and thinness, and has a wide range of used temperatures, which is superior to that of the conventional thin display. However, the above-mentioned organic EL device has a drawback that the luminescence period such as luminescence luminance and luminescence uniformity is remarkably deteriorated depending on the use under a certain period of time under high temperature conditions. One reason for such deterioration in luminescence performance is the generation of a luminescent portion (black dot). It is known that such black spots are caused by water or organic gas intruding into the surface portion of the cathode of the laminate, and the separation between the light-emitting layer and the cathode or the oxidation of the surface of the cathode, resulting in electric power generation. Then, the moisture, oxygen, or organic system for this reason is brought into contact with the above-mentioned laminated body due to, for example, an atmosphere gas existing inside the element, a gas invading the part from the outside, or a gas adsorbed to the constituent part or the constituent material. The production of black spots. The external gas is produced by the Electro-Mechanical Assembly (EL). In the optical layer of the EL layer, the angle is wide, that is, "use and energy can be compared with the initial!", no oxygen or organic gas is formed, and the component is separated from the product. 200918635 In the organic EL device of the material of the moisture of the internal atmosphere gas, for example, a member for an EL element in which a removal agent for removing a predetermined gas component is contained in a container having a region partially composed of a porous material has been proposed (for example, refer to Patent Document 1) In addition, a fixing member in which the gel fraction of the adhesive is 7% or more in order to prevent the organic gas from being released from the adhesive is used (see, for example, Patent Document 2). For a sheet having a removing agent for removing the gas component, for example, a gas component-treated sheet in which a particulate removing agent that removes a predetermined gas component is dispersed in a gas-permeable base material film has been proposed (for example, refer to the patent document) 3) On the other hand, regarding the removal sheet for fixing to the package frame, for example, it has been proposed to have a remover for removing a specified gas component, A removal sheet that is fixed to the removal agent and that causes the removal agent to follow the adhesive member on the inner surface of the EL element (for example, 'refer to Patent Document 4). However, in all of the above proposals, the fixing agent is used to fix the removal agent in the element. The material 'described is a pressure-sensitive adhesive or the like, but these are only generally known adhesive materials; there is no description of the composition and composition of the organic gas (outside gas) which has an adverse effect on the luminescent properties. In order to reduce the thickness of the EL element, it is desirable to further thin the two-sided adhesive sheet to be used. Patent Document 1: Japanese Patent No. 3447 65 3 Patent Document 2: Japanese Patent No. 3 5 5 8 5 8 8 Patent Document 3 Japanese Patent Application Publication No. 2001-278999 (Patent Document 4): Japanese Patent Application Publication No. Hei No. H0 1 - 3 4 5 1 7 No. 200918635 SUMMARY OF INVENTION Technical Problem The present invention is to provide In these cases, the amount of external air generated is small and has a stomach property, and can be used for fixing and removing the gas existing in the internal space of the EL element and adversely affecting the EL element. For the purpose of removing the adhesive sheet of the member. The inventors of the present invention have intensively studied in order to achieve the above object, and as a result, it has been found that by using a (meth) acrylic acid ester ester having a low carbon number hospital base containing a vinegar portion The crosslinked product of the unit and the carboxyl group-containing acrylic copolymer containing the reactive functional group may be used as an adhesive for the adhesive layer of the double-sided adhesive sheet. The present invention is based on the object. That is, the present invention provides: (1) A double-sided adhesive sheet which is a double-sided adhesive sheet for removing a removal member of a specified gas component existing in an internal space of an electroluminescence (EL) element. It is characterized in that an adhesive layer is provided on both surfaces of the substrate sheet, and the adhesive constituting each adhesive layer is a crosslinked product containing a carboxyl group-free acrylic copolymer, wherein the carboxyl group-free acrylic copolymer contains: An alkyl (meth) acrylate unit having a carbon number of 4 or less, and an ethylenically unsaturated monomer unit having a reactive functional group; (2) as described above (1) The ratio of the (Α) unit to the (Β) unit in the acrylic copolymer containing no carboxyl group, in the mass ratio, is 95:5 to 99.5:0.5; (3) as described above (1) The two-sided adhesive sheet of the above-mentioned item (3), wherein the carboxyl group-containing acrylic acid 200918635-based copolymer further contains (c) a morpholino compound unit containing an ethylenically unsaturated group; (4) the double-sided adhesive sheet according to the above (3), wherein The content of the (C) unit is 2 to 30 parts by mass based on 100 parts by mass of the total of the (A) unit and the (B) unit; (5) The two-sided adhesive sheet according to the above (1), wherein (B) The ethylenically unsaturated monomer unit of the reactive functional group is a hydroxyl group-containing ethylenically unsaturated monomer unit; (6) The double-sided adhesive sheet according to the above (1), wherein the temperature is heated at a temperature of 12 ° C for 10 minutes. The amount of the external gas generated is less than 〇.5 " g/cm2 in terms of n-decane; (7) The double-sided adhesive sheet as described in the above (1), wherein the thickness of the adhesive layer is 2 in total (z) The two-sided adhesive sheet as described in the above (1), wherein the adhesive layer from one side to the adhesive layer of one side The adhesive layer side 'aperture formed 20~200 / zm, pore density is 30 to 10,000 / 10 cm2 of the through holes. Advantageous Effects of Invention According to the present invention, it is possible to provide a gas having a small amount of external air generated and having high adhesiveness, and can be used for fixing and removing a specified gas component existing in an internal space of an EL element, that is, a gas which adversely affects the EL element. The component of the component is adhered to both sides of the member. [Embodiment] The double-sided adhesive sheet of the present invention is for fixing and removing the specified gas $β @卩$$ member existing between the inner portions S of the EL element, and its use form is explained in accordance with the accompanying drawings. The element 1 is in the form of a flat plate. Fig. 1 is a schematic cross-sectional view of the EL element. Is the substrate 2 of Elj 200918635 formed with an anode 8 and a cathode 6? The laminated body (EL laminate) 5 is provided with a frame (H) on the substrate 2 so as to cover the laminated body $, and the peripheral portion of the package frame 3 and the substrate 2 are provided by a package material. Fixed. Further, the member 9 is fixed to the top of the package frame 3 by the adhesive sheet 1Q. (4) The gas component such as moisture or organic gas which is a cause of intrusion into the black spot inside the EL element 1 is removed by the removing member 9. Further, in the first drawing, the removal member 9 is fixed to the ceiling of the package casing 3. However, the fixing position is not particularly limited, and may be fixed to the side wall of the package casing 3, for example. Fig. 2 is a cross-sectional view showing an example of a double-sided adhesive sheet of the present invention, in which the double-sided adhesive sheet 10 is formed by providing adhesive layers 1 2 and 3 on both surfaces of the base sheet 11. In the present invention, the removing member is not particularly limited, and any of the removing members used for removing the gas component which is a cause of black spots can be appropriately selected from the previous elements. In the above-mentioned removal member, a sheet obtained by dispersing a sorbent, a moisture absorbent (drying agent), a deoxidizing agent or the like in a gas permeable plastic sheet, or a removing agent is stored in a ventilating container. And so on. [Base material sheet] The base material sheet in the double-sided pressure-sensitive adhesive sheet of the present invention is not particularly limited as long as it is difficult to generate an organic gas, and various types can be used. Specific examples thereof include polyolefins such as polyethylene and polypropylene, polyesters such as polyethylene terephthalate and polybutylene terephthalate, and resins such as polyimine and polyamide. And the metal vapor deposition of aluminum or the like is performed on the sheet; the synthetic paper '200918635 paper containing impregnated paper, etc.; the metal foil such as aluminum foil or copper foil. The thickness of the substrate sheets is not particularly limited, but is usually in the range of about 2 to 50 // m. From the viewpoint of the film formation, it is preferably in the range of about 3 to 2 Å v m . When a resin sheet is used as the base sheet, surface treatment such as an oxidation method or a roughening method can be performed in order to improve the adhesion to the adhesive layer provided thereon. The oxidation method may, for example, be a corona discharge treatment, a chromic acid treatment (wet), a flame treatment, a hot air treatment, an ozone, an ultraviolet irradiation treatment, or the like. Further, as the unevenness method, for example, a spray may be mentioned. Sand method, solvent treatment method, etc. Although these surface treatment methods are appropriately selected depending on the type of the substrate sheet, it is preferable to use a corona discharge treatment method from the viewpoints of effects and workability. Further, a plasma treatment for setting the electric paddle layer can be performed. [Adhesive Layer] Each of the adhesive layers provided on both surfaces of the base sheet is characterized in that it is composed of an adhesive containing a crosslinked product of a carboxyl group-free acrylic copolymer, wherein the adhesive layer The carboxyl group-containing acrylic copolymer contains (A) an alkyl group of (meth)acrylate having a carbon number of 4 or less, (B) an ethylenically unsaturated monomer unit containing a reactive functional group, and optionally (C) a morpholino compound unit containing an ethylenically unsaturated group. When an adhesive composed of a carboxyl group-containing acrylic copolymer is used, the side chain portion of the acrylate monomer is decomposed by heat and humidity in the presence of a carboxyl group such as acrylic acid or methacrylic acid, and the decomposition product is exothermic. Form is produced. (Monomer) A monomer which is formed into a (meth) propylene-10-200918635 acid alkyl ester unit having 4 or less carbon atoms in the alkyl group of the above (A) unit, and specific examples thereof include (meth)acrylic acid Ester, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, (methyl) Second butyl acrylate, tert-butyl (meth) acrylate, and the like. Wherein 'from the balance with viscosity, cohesive force, and lowering the boiling point of residual monomers and side chain decomposition products after polymerization, and removing the volatiles by thermal drying when the adhesive is applied, N-butyl acrylate or methyl (meth) acrylate is preferred. These may be used alone or in combination of two or more. The alkyl (meth)acrylate having an alkyl group having more than 4 carbon atoms causes an increase in the amount of external air produced as described below, and the above object of the present invention cannot be attained. The reactive functional group in the ethylenically unsaturated monomer containing the reactive functional group in the above (B) unit is a group such as a hydroxyl group or a mercapto group which can be reacted with an isocyanate or the like during crosslinking, and thus a genus can be used. The ethylenically unsaturated monomer having no carboxyl group and having a hydroxyl group or a mercapto group is used as the ethylenically unsaturated monomer having a reactive functional group. / : The hydroxyl group-containing ethylenically unsaturated monomer may, for example, be a hydroxyalkyl (meth)acrylate such as 2-hydroxyethyl (meth)acrylate or 2-hydroxypropyl (meth)acrylate. 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, and the like. Examples of the ethylenically unsaturated monomer containing a guanamine group include, for example, acetonitrile, N,N-dimethyl decylamine, hydrazine, hydrazine dimethyl methacrylamide, hydrazine- An acrylamide-based monomer such as methacrylamide or hydrazine-hydroxymethylmethacrylamide. -11 - 200918635 These reactive functional group-containing ethylenically unsaturated monomers may be used alone or in combination of two or more. However, in the case of an ethylenically unsaturated monomer containing a guanamine group, excess amount The addition increases the Tg of the copolymer and causes a decrease in wettability. As a result, sufficient adhesion cannot be obtained, and it is difficult to apply it to the present invention. Therefore, it is preferable to use as little as possible during use. In the present invention, it is preferred to use a hydroxyl group-containing ethylenically unsaturated monomer from the viewpoint of imparting a monomer having a unit of (B) from the viewpoint of imparting an acrylic copolymer which does not change color due to heat. In the present invention, an ethylenically unsaturated carboxylic acid unit such as a (meth)acrylic acid unit cannot be introduced into an acrylic copolymer as a unit (B) unit of a reactive functional group-containing ethylenically unsaturated monomer unit. Thereby, an acrylic acid-like copolymer in which the side chain is completely free of a carboxyl group can be obtained. The double-sided adhesive sheet having the adhesive layer composed of the adhesive containing the acrylic copolymer has a small amount of external air generated, and can be used for fixing and removing the internal space existing in the EL element and adversely affecting the EL element. A member for removing a gas component. In the present invention, in the acrylic copolymer containing no carboxyl group, the content ratio of the unit (A) to the unit (B) is calculated from the viewpoint of the balance between the cohesive force of the adhesive and the adhesive force. Good for 95: 5 to 99.5: 0.5, better for 96: 4 to 99: 1. The acrylic copolymer containing no carboxyl group in the present invention preferably contains a morpholino compound unit containing an ethylenically unsaturated group as a unit (C) from the viewpoint of balance between adhesion and viscosity. As the morpholino monomer forming the (C) unit, for example, N-vinylmorpholine, N-allylmorpholine, N-(meth)acryloylmorpholine or the like can be used. The morpholino monomer may be used singly or in combination of two or more. In the viewpoint of good copolymerizability between the monomer forming the unit (A) and the monomer forming the unit (B), N-(meth)acrylinylmorpholine is preferred. In the present invention, the content of the unit (C) is from the viewpoint of the balance between the adhesive force and the viscosity of the adhesive, and is 100 parts by mass with respect to the total amount of the unit (A) and the unit (B). It is preferably 30 parts by mass, more preferably 4 to 25 parts by mass. In the double-sided adhesive sheet of the present invention, the above (C) unit in the acrylic copolymer forming the adhesive layer is incorporated into the copolymer, and the side chain contains the morpholine structure by the following isocyanate crosslinking agent. In the cross-linking reaction to be carried out, the cross-linking accelerator has a role of being able to obtain the necessary adhesive physical properties without adding a low-molecular weight cross-linking accelerator which is used in the past, so that no external air caused by the low-molecular weight substance is generated. In the above-mentioned acrylic copolymer, styrene, vinyl acetate, or an ethylenically unsaturated group-containing imidazole which is (D) forms another unit of ethylenically unsaturated monomer at the time of polymerization may be added as needed. A carboxyl group-free ethylenically unsaturated monomer other than the ethylenically unsaturated monomer of the above (A) to (C) unit, such as a compound or (meth)acrylonitrile. The content of the above (D) unit in the carboxyl group-free acrylic copolymer is a total amount of the unit (A) and the unit (B) from the viewpoint of the balance between the adhesiveness and the adhesive force of the adhesive. The mass part 'is preferably 0 to 1 part by mass, more preferably 〇 to 5 parts by mass. (Production of Acrylic Copolymer) In the present invention, the acrylic copolymer used in the adhesive is preferably dissolved in a hydrocarbon such as toluene or xylene or an ester such as ethyl acetate by dissolving each of the above monomers. After adding an organic solvent, etc., 'adding previously known azobisiso-13- 200918635 butyronitrile, 2,2'-azobis(2-amidinopropane) dihydrochloride, 4,4,-azo double An azo-based polymerization initiator such as (4-cyanoshikimate) or a peroxide-based polymerization initiator such as benzamidine peroxide is produced by radical polymerization. The amount of the above polymerization initiator is preferably in the range of from 0 to 10 parts by mass, more preferably in the range of parts by mass, based on 1 part by mass of the total amount of the monomers. In the polymerization reaction, as the polymerization proceeds, the monomer and the polymerization initiator gradually decrease, and the probability of encountering the two becomes very low in the later stage of polymerization, so that the monomer remains in the system. The residual monomer is not the cause of the odorous and toxic compound because one of the adhesive sheets is odorous, so it is not good to remain in the adhesive. A small amount (less than a few % of the monomer fed in) is separated from the polymer, which is not preferable from the viewpoint of energy economy. Therefore, when the polymerization is about to end, a method of adding a subsequent addition polymerization initiator called a preservative to the system and polymerizing the residual monomer as much as possible to reduce the residual monomer is usually employed. The radical polymerization 'is usually obtained by heating at about 10 to 90 ° C, preferably at about 50 to 90 ° C for about 1 to 2 hours, preferably about 3 to 10 hours, to obtain an acrylic copolymer. Organic solvent solution. The weight average molecular weight of the obtained carboxyl group-free acrylic copolymer is usually 200,000 or more', preferably 400,000 to 2,000,000, more preferably 500,000 to 1,000,000. The method of polymer quantification includes selecting a solvent that is difficult to carry out as a solvent, increasing the concentration of the monomer mixture in the reaction solution (to reduce the solvent concentration in order to prevent chain transfer to the solvent), and reducing the concentration of the polymerization initiator (relative to the monomer). In the method of performing polymerization at a lower reaction temperature, a carboxyl group-free acrylic copolymer having a weight average molecular weight as described above can be obtained by carrying out the polymerization of -14 to 18,835,635. Further, the above weight average molecular weight is converted into polystyrene by a gel permeation chromatography (GPC) method. In the present invention, the carboxyl group-free acrylic copolymer may be used singly or in combination of two or more. (Crosslinking agent) In the present invention, the adhesive constituting the adhesive layer contains the above-mentioned crosslinked product containing no carboxylic acid (based on the acrylic copolymer as a resin component) for obtaining crosslinks of the crosslinked product. The polyisocyanate crosslinking agent is preferably a polyisocyanate crosslinking agent. The polyisocyanate crosslinking agent is a compound having two or more isocyanate groups in the molecule, and specific examples thereof include toluene diisocyanate (TDI), tetramethylene diisocyanate, and Methylene diisocyanate (HMDI), isophorone diisocyanate (IPDI), xylene diisocyanate (XDI), hydrogenated toluene diisocyanate, diphenylmethane diisocyanate, hydrogenated diphenylmethane diisocyanate, and a polyisocyanate compound or an isocyanurate or a biuret-type compound obtained by addition reaction with trimethylolpropane or the like; further, with a known polyether polyol or polyester polyol, A urethane prepolymer type polyisocyanate obtained by an addition reaction such as an acrylic polyol, a polybutadiene polyol, or a polyisoprene polyol. One type may be used alone or in combination of two or more. The crosslinking agent is used in an amount of about 0.1 to 10 parts by mass based on 100 parts by mass of the carboxyl group-free acrylic copolymer, by adjusting the crosslinking. The amount of the agent used may be a permanent adhesive or re-peelable adhesive. -15- 200918635 (Formation of Adhesive Layer) The double-sided adhesive sheet of the present invention has an adhesive layer on both sides of the substrate sheet, for example, It can be produced by the following method. First, an adhesive solution containing the above-mentioned carboxyl group-free acrylic copolymer cross-linking agent and optionally a solvent or various additives is prepared. The above various additives are not damaged by the present invention. In the mesh, an oxidation inhibitor, an ultraviolet absorber, a dopant, a light stabilizer, a sputum, etc. can be suitably used. Further, the solvent can be appropriately selected from the user of the acrylic adhesive coating liquid. / Next, the above-mentioned adhesive coating liquid is prepared by a conventionally known method such as spin coating, spray coating, bar coating, knife coating, roll coating, doctor die coating, gravure coating, and the like. The release layer applied to the release layer is heated at about 80 to 150 ° C for about 30 seconds to 5 minutes in order to prevent the solvent and the low-boiling component from remaining, and two pieces of the adhesive layer are prepared by using the adhesive. The layer is attached to both sides of the base sheet and is opposed to each other to obtain the intended double-sided adhesive sheet. Further, the release sheet is usually attached to the protective layer before use. Further, the above-mentioned adhesive coating liquid is directly used as described above. It is coated on both sides of the substrate sheet and heated to form an adhesive layer on which the release sheet can be attached for protection. The thickness of the adhesive layer thus formed is not particularly limited, but is selected as a single-sided adhesive layer. In other words, it is usually selected from the range of 2 to 30 μ, preferably in the range of 3 to 20 # 111. Further, in view of the fact that the EL element requires film formation in recent years, the total of the two layers is preferably 25 # m. [Peeling sheet] The layer is coated with the above-mentioned agent. Method, example coating method, after surface, temperature: |J off-chip, , can be adhesively applied, will be treated, can be appropriate m of the model, from the following -16 - 200918635 for the above peeling sheet 'can be listed in For example, a cellophane paper, a coated paper, a paper-grade paper substrate, or a laminated paper made of a thermoplastic core such as polyacetal or polyacryl can be laminated on the paper substrate, and cellulose is used on the substrate. Paper substrate made of quilted starch such as starch, polyvinyl alcohol or acrylic-styrene resin, or polyethylene terephthalate, polybutylene terephthalate or polyethylene naphthalate A polyester film such as an ester, a plastic film of a polyolefin film such as polyethylene or polypropylene, and a film which is easily treated on the plastic film, and the like, and a release agent. For the release agent for forming the release agent layer, for example, a gum elastomer such as an olefin resin, an isoprene resin or a butadiene resin, a long-chain alkyl resin or an alkyd resin can be used. Resin, fluorine-based resin, or polyoxynoxy resin. The thickness of the release agent layer formed on the substrate is not particularly limited. However, when the release agent is applied in a solution state, it is preferably 0.05 to 2.0 // m, more preferably 0.1 to 1.5/zm. In the case where a release agent layer is formed using a thermoplastic resin such as polyethylene or polypropylene, the thickness of the release agent layer is preferably 3 to 50 μm, more preferably 5 to 40 / / m. [Two-sided adhesive sheet] The amount of gas generated by the double-sided adhesive sheet of the present invention produced as described above is less characteristic. In the present invention, the amount of external air generated is compared in terms of n-decane. The generation of black spots can be reduced by the amount of gas generated from the adhesive layer not exceeding 0.5 #g/cm2 in terms of n-decane conversion. The amount of generated gas (A) when the double-sided adhesive sheet of the present invention is heated at a temperature of 120 ° C for 10 minutes, calculated in terms of n-decane, does not reach 〇.5 " g/cm2 'more -17- 200918635 Since it is 0.1 / zg / cm2 or less 'and it does not corrode the object, it is suitable for the long life of an EL element. Further, the amount of generated gas is enthalpy measured by peeling off the peeling sheet. Further, a specific method of measuring the generated gas will be described in detail in the examples. When the base material sheet is thinned, when the double-sided adhesive sheet having the removal member attached to the one surface is attached to the package frame, air is attached to the adhesive layer and the package frame in a fitted state. The reason for the low adhesion. In order to prevent this, it is preferable to form a through hole having a pore diameter of about 20 to 200 #m and a pore density of 30 to 10,000/10 cm2 from the adhesive layer on one side to the adhesive layer on the other side. Thereby, the air between the adhesive layer and the package frame is released by the through-holes to the opposite surface, and is further released by the air-permeable removing member, so that the air can be prevented from being fitted. The cross-sectional shape of the through-hole is not particularly limited, and the pores of the through-hole in the substrate sheet and the adhesive layer are about 20 to 2 0 // m, preferably 5 0 to 1 5 0 // m . If the hole diameter of the through hole is 20 / z m or more, air or gas is easily eliminated; if the hole diameter of the through hole is 200 // m or less, the adhesion is good. The through hole has a pore density of about 30 to 10,000 / l 〇 cm 2 , preferably 50 to 5,000 / 10 cm 2 . When the pore density of the through-hole is 30 /10 cm 2 or more, air or gas is easily removed, and if the pore density of the through-hole is 10 000 /10 cm 2 or less, the mechanical strength of the double-sided adhesive sheet is good. The through holes are preferably formed by laser processing. When laser processing is performed, it is easy to form a fine through hole having good air-eliminating properties at a desired hole density. -18- 200918635 There are no special restrictions on the types of lasers used in laser processing. For example, carbon dioxide (CCh) lasers, TEA-CCh lasers, YAG lasers, UV-YAG lasers, and excimer mines can be utilized. Shot, semiconductor laser, YV〇4 laser, YLF laser, etc. Fig. 3 is a cross-sectional view showing a state in which the adhesive layer through-holes from one adhesive layer to the other are formed in the double-sided adhesive sheet of the present invention. In the figure, reference numeral 11 is a base material sheet, 12 and 13 are adhesive layers, and 14 is a through hole. EXAMPLES Hereinafter, the present invention will be described in further detail by way of examples, but the invention is not limited to the examples. Furthermore, the performance evaluation methods of the two-sided adhesive sheets obtained in the respective examples are shown below. (1) Adhesive force The adhesive sheets on both sides of the release sheet are removed, and the one-side release sheet is removed at 23 ° C, 50% R Η environment, and the exposed adhesive layer is applied to the thickness of 25 // m polyethylene terephthalate film, while removing the other side of the release sheet, the exposed adhesive layer is then applied to the stainless steel plate, according to Π SZ 0 2 3 7 ^ after attachment for 24 hours, '1 Peel at 80 degrees and measure adhesion (n / 2 5 mm). (2) The amount of external air generated is sealed in an ampoule in the sample (2 0 c m2). The ampoule is purged by a gas chromatography mass spectrometer (GC Mass) [made by JEOL, JHS -100A"]" was heated at 120 °C for 10 minutes, gas was taken, and then introduced into GCMass ("TurboMass" manufactured by PERKINELMER), and the amount of n-decane was calculated from a calibration curve prepared using n-decane. The amount of gas generated by μ g/cm 2 ). Further, the weight average molecular weight in each case means the weight average molecular weight converted to polystyrene measured by a gelation chromatography -19-200918635 (GPC) method. Example 1 (1) Preparation of the adhesive composition solution: 97.4 parts by mass of n-butyl acrylate as the component (A), 2.0 parts by mass of methyl acrylate, and 0.6 parts by mass of 2-hydroxyethyl acrylate as the component (B) The constitutive mixture is used as a polymerization initiator azobisisobutyronitrile. 1 part by mass, 150 parts by mass of ethyl acetate as a solvent is placed in the reactor, and the temperature is raised to 80 to 90 ° C under stirring. Further, a polymerization reaction was carried out, and then 0.1 mass part of azobisisobutyronitrile was added thereto in a polymerization solvent containing 10 parts by mass of toluene, and polymerization was carried out for 7 hours. After the completion of the reaction, a 40% by mass solution of a carboxyl group-free acrylic copolymer having a weight average molecular weight of 500,000 was prepared by adding a diluent solvent (a mixed solvent of toluene and ethyl acetate). Toluene diisocyanate (TDI)-based crosslinking agent ("Coronate L55E"' manufactured by Japan Polyurethane Co., Ltd., solid content 55 mass, was added to 100 parts by mass of the acrylic copolymer solution (solid content: 40 parts by mass). %) 1 part by mass, prepared into an adhesive composition solution. (2) The two-sided adhesive sheet was produced by using a polyethylene terephthalate film ("T1 00" manufactured by Mitsubishi Polyester Film Co., Ltd.) which was peeled off and had a thickness of 3 8 // m as a release sheet. The adhesive composition solution obtained in the above (1) was applied to the release-treated surface so that the thickness after drying became 9 #m, and then dried at 120 ° C for 2 minutes to form an adhesive layer. Next, a polyethylene terephthalate (PET) film ("S10" manufactured by Toray Industries, Inc.) having a thickness of 12 //m as a substrate sheet was attached to the adhesive layer to form a single-sided adhesive sheet. . Further, the adhesive composition solution is laminated on another peel-treated polyethylene terephthalate film (previously) in the same manner as the thickness after drying to 9 m-20-200918635. A PET film (thickness: 1 2 /zm) of the previously produced single-sided adhesive sheet was applied to the surface of the adhesive composition to form a double-sided adhesive sheet. The properties of the two-sided adhesive sheet are shown in Table 1. Example 2 (1) Preparation of Adhesive Composition Solution Except that 79.0 parts by mass of n-butyl acrylate as the component (A) and 2.0 parts by mass of yttrium acrylate 'methyl acrylate, 2-hydroxyethyl acrylate (component) was used. 2.0 parts by mass of the ester and 17.0 parts by mass of ruthenium-acryloyl morpholine as the component (C), in place of 97.4 parts by mass of n-butyl acrylate which is a (Α) component, and 2.0 parts by mass of methyl acrylate. (In addition to the mixture of 0.6 parts by mass of the 2-hydroxyethyl acrylate of the (Β) component, the mixture was prepared in the same manner as in [1] Preparation of the adhesive composition solution of Example 1 to prepare an adhesive composition solution. . (2) The production of the double-sided adhesive sheet was carried out in the same manner as in [(2) Preparation of the double-sided adhesive sheet] of Example r1 except that the adhesive composition solution obtained in the above (1) was used, and the two-sided adhesive sheet was formed. sheet. The properties of the two-sided adhesive sheet are shown in Table 1. Examples 3 and 4 and Comparative Examples 1 and 2 The adhesive composition was prepared in the same manner as in Example 1 using the copolymer component of the type and amount shown in Table 1, and then a double-sided adhesive sheet was produced. The properties of each of the two-sided adhesive sheets are shown in Table 1. Example 5 Polyethylene terephthalate (Toray 21 - 200918635 "F53") having a thickness of 6.3 # m was used as a substrate sheet, and except for the thickness of the adhesive layer (single side 4am, single side 4 // A double-sided adhesive sheet was produced in the same manner as in Example 2 except for m). A double-sided adhesive sheet having a through-hole was formed by forming a through-hole having a diameter of 50/zm and a hole density of 200/10 cm2 on a double-sided adhesive sheet to which both of the produced release sheets were attached. The properties of the two-sided adhesive sheet are shown in the table. Table 1 Example Comparative Example 1 2 3 4 5 2 Each unit (% by mass) of the acrylic copolymer butyl acrylate (A) 97.4 79.0 61.0 93.0 79.0 94.0 Methyl acrylate (A) 2.0 2.0 20.0 2.0 _ 2.0 Acrylic acid 2- Ethylhexyl ester 93.0 2-hydroxyethyl acrylate (B) 0.6 2.0 2.0 2.0 2.0 2.0 2.0 Acrylic acid 2.0 N-propylene decylmorpholine 17.0 17.0 5.0 17.0 5.0 Adhesion (N/25mm) 5.13 7.13 6.50 5.30 4.50 6.25 5.50 Gas generation amount (#g/cm2) 0.04 0.04 0.04 0.04 0.03 0.77 0.65 From the above results, it was confirmed that the adhesive sheet obtained in the examples showed high adhesion. Furthermore, in terms of external gas generation, it is confirmed that the amount of production is very low. Further, even if the double-sided adhesive sheet which is thin and has a thin overall thickness as seen in the fifth embodiment, by providing the through-holes, it can be easily attached to the object without vacuuming. On the other hand, in the case of using an alkyl group having more than 4 carbon atoms and acrylic acid, the amount of external gas generated is large. INDUSTRIAL APPLICABILITY The double-sided adhesive sheet of the present invention has a small amount of external air generated and has high adhesive property. A removal member that can be used for fixing and removing a gas component existing in an inner space of an el element and adversely affecting the EL element. . [Simple description of the drawing] [Fig. 1] is a schematic sectional view of the E L element. Fig. 2 is a cross-sectional view showing an example of a double-sided adhesive sheet of the present invention. [Fig. 3] Fig. 3 is a cross-sectional view showing a state in which a through-hole is formed in an adhesive layer from one adhesive layer to the other in the double-sided adhesive sheet of the present invention. [Description of main components] 1 EL component 2 Substrate 3 Package frame 4 Sealing material 5 EL laminate 6 Cathode 7 Organic light-emitting layer 8 Anode 9 Removal member 10 Double-sided adhesive sheet 11 Substrate sheet 12 Adhesive layer 13 Adhesive layer 14 Through hole -23-