200920595 九、發明說明 【發明所屬之技術領域】 本發明係關於多層微多孔聚烯烴膜，其具有適當的滲 透性、接腳耐壓強度（pin puncture strength)、關閉溫度 、關閉速度、熔融溫度及厚度均勻度。本發明亦關於由如 是多層微多孔膜所形成的電池隔板、以及包含如是隔板的 電池。本發明之另一態樣係關於製造該多層微多孔聚烯烴 膜的方法、使用了如是膜作爲隔板之電池的製造方法、以 及使用如是電池的方法。 【先前技術】 多孔聚烯烴膜可用於，例如，一次及二次鋰電池、鋰 聚合物電池、鎳氫電池、鎳鎘電池、鎳鋅電池、銀鋅電池 等等，作爲電池隔板。當微多孔聚烯烴膜用於電池隔板（ 尤指鋰離子電池隔板）時，膜的效能會顯著地影響電池的 性質、生產性及安全性。因此，該微多孔聚烯烴膜應具有 適當的機械性質、耐熱性、滲透性、尺寸安定性、關閉性 質、熔融性質等等。如已眾所皆知的，電池宜具有相對較 低的關閉溫度及相對較高的熔融溫度，以改善電池的安全 性，尤其是對於在製造、充電、再充電、使用及/或儲存 期間會暴露於高溫的電池而言。隔板滲透性的改善通常會 使得電池的儲存電容量（storage capacity)獲得改善。高 速關閉速度乃改良電池安全性所需者，尤其係當該電池係 於過度充電的條件下操作時。改良的接腳耐壓強度係想要 -5- 200920595 的，因爲電池之電極的粗糙會在製造期間’剌穿隔板’而 造成短電路的發生。改良的厚度均勻度係希望有的’因爲 厚度的變動在將薄膜纏繞在芯上時，會導致製造的困難。 厚度變動亦會在電池內造成非等向性的溫度變動’這在隔 板相對較薄的情況下’會導致產生電池熱點（溫度較高的 區域）。 一般而言，僅含有聚乙嫌的微多孔膜（亦即’由聚乙 烯所組成或是實質上由聚乙烯所組成之膜）具有低的熔融 溫度，而僅含有聚丙烯的微多孔膜具有高的關閉溫度。因 此，包含聚乙烯及聚丙烯作爲主成份之微多孔膜已被建議 作爲改良的電池隔板。因而提供由聚乙烯樹脂及聚丙烯樹 脂所形成的微多孔膜、以及包含聚乙烯及聚丙烯的多層微 多孔膜，係人們所企求的。 例如，JP7-216118A揭示了具有適當關閉溫度及機械 強度的電池隔板。該專利申請案揭示··包含了具有二層微 多孔層之多層多孔薄膜的電池隔板。該二層皆可含有聚乙 烯及聚丙烯，但是相對含量不同。例如，在第一微多孔層 內，聚乙烯的百分比爲〇重量°/❶至20重量％ ’而在第二微 多孔層內則爲21重量％至60重量％ (基於聚乙烯及聚丙 烯的合計重量）。薄膜（亦即，該二微多孔層）內的聚乙 烯總量爲2重量％至40重量％ (基於該多層微多孔薄膜的 重量）。 J P 1 0 - 1 9 5 2 1 5 A揭示了相對較薄的電池隔板，其具有可 接受的關閉及接腳上拉（pin-pulling )特性。「接腳上拉 200920595 (pin pulling)」一詞係指由隔板、陰極片及陽極片之層 合物拉出金屬接腳的相對容易度，該層合物係纏繞接腳而 形成一環形的層合物。該多層多孔薄膜含有聚乙烯及聚丙 烯，但是相對含量不同。在內層中之聚乙烯的百分比爲〇 重量％至2 0重量％，而在外層中則爲6 1重量％至1 0 0重量 % (基於聚乙烯及聚丙烯的總重）。 JP10-279718A揭示了一種隔板，其係設計用來在電池 過度充電時，防止鋰電池內之無法接受的大量溫度增加。 該隔板係由聚乙烯及聚丙烯所製得之多層多孔薄膜所形成 的，在各層中的聚乙烯及聚丙烯相對量不同。該薄膜具有 缺聚乙烯層，其聚乙烯的含量爲〇重量％至20重量％ (基 於缺聚乙烯層的重量）。第二層係富含聚乙烯的層，其含 有0.5重量％或更多之熔融指數爲3或更高的聚乙烯，且 所具有的聚乙烯含量爲61重量％至100重量％ (基於富含 聚乙烯層的重量）。 進一步改良微多孔聚烯烴膜的滲透性、接腳耐壓強度 、以及關閉速度係有需要的。此外’還有需要進一步改良 微多孔聚烯烴膜的厚度均勻度，俾便在使用作爲電池隔板 時，降低短電路的可能性。 【發明內容】 發明之總論 於一體系中，本發明係關於多層微多孔膜，其包含： 第一個層物質，其包含第一個聚乙烯以及第一個聚丙 200920595 烯以及 第二個層物質，其包含第二個聚乙稀以及弟一 烯，第二個聚丙烯具有重量平均分子量6·5χ105或 及溶化熱95 J/g或更高，所具有之分子量爲U 更大之第二個聚丙烯部分係佔10質量％或更多（基 個聚丙烯的質量）。該多層膜可包含’例如’第一 孔層，其含有第一個微多孔層物質；以及第二個微 ，其含有第二個微多孔層物質。例如，申請專利範 項之多層膜可包含： 第一個微多孔層，其含有第一個微多孔層物質 個微多孔層，其含有第一個微多孔層物質；以及第 多孔層，其含有第二個微多孔層物質，該第二個微 係位於該第一個及第三個微多孔層之間。 於一可替代的形式中，該多層微多孔膜可包含 個微多孔層，其含有第二個微多孔層物質；第三個 層，其含有第二個微多孔層物質；以及第二個微多 其含有第一個微多孔層物質，該第二個微多孔層係 一個及第三個微多孔層之間。 於另一體系中，本發明係關於一種製造微多孔 法，其包含： (1)將第一個聚乙烯樹脂、第一個聚丙烯樹 及第一個加工溶劑倂合，而形成第一個聚乙烯溶液 ’該第一個聚乙烯樹脂以及第一個聚丙烯樹脂一起 一個聚烯烴組成物；且其中，在第一個聚烯烴組成 個聚丙 更大以 Χίο6 或 於第二 個微多 多孔層 圍第1 :第三 二個微 多孔層 :第一 微多孔 孔層， 位於第 膜的方 脂、以 ，其中 構成第 物內之 -8- 200920595 第一個聚乙烯的量係至少約8 0重量％ (基於第一個聚烯烴 組成物的重量）：以及 (2)將第二個聚乙烯樹脂、第二個聚丙烯樹脂、以 及第二個加工溶劑倂合，而形成第二個聚烯烴溶液，其中 該第二個聚乙烯樹脂以及第二個聚丙烯樹脂一起構成第二 個聚烯烴組成物；且其中，在第二個聚烯烴組成物內之第 二個聚乙烯的量係至少約5 0重量％ (基於第二個聚烯烴組 成物的重量）；第二個聚丙烯樹脂具有重量平均分子量 6.5x10s或更大以及熔化熱95 J/g或更高，所具有之分子 量爲1.8X106或更大之第二個聚丙烯部分係佔10質量％或 更多（基於第二個聚丙烯樹脂的質量）。 在一體系中，本發明還包含： (3 )令至少一部分第一個聚烯烴溶液擠壓通過模具 且共擠出至少一部分第二個聚烯烴溶液，形成多層的擠出 物， (4)將該多層擠出物冷卻，而形成多層片狀物， (5 )自該多層片狀物移除至少部分的加工溶劑，而 形成已去除溶劑的片狀物，以及 (6 )自該片狀物移除至少部分任何揮發性物種，而 形成多層微多孔膜。 於又另一體系中，本發明係關於一電池，其包含陽極 、陰極、以及電解質、及前述體系的多層膜，其中，該多 層膜將至少陽極與陰極隔離。該電池可用作爲電荷的來源 或儲槽。 -9- 200920595 發明之詳細說明 [1]多層微多孔聚烯烴膜的組成物及結構 於一體系中，多層微多孔膜包含二層。 ，上層）包含第一個微多孔層物質，而第二 層）包含第二個微多孔層物質。例如，該膜 層（當在與該膜的橫向及機械方向呈直角的 來看時），而由頂層來看時，底層則藏在其 系中，該多層微多孔膜包含三或更多層，其 作爲「表面」或「皮」層）包含第一個微多 至少一層的中間層包含第二個微多孔層物質 系中，當多層微多孔膜包含二層時，第一層 或是由）第一個微多孔層物質所組成，而第 上由（或是由）第二個微多孔物質所組成。 膜包含三或更多層的相關體系中，外層係實 由）第一個微多孔層物質所組成，而至少一 係實質上由（或是由）第二個微多孔層物質 可被稱作爲「聚烯烴膜」’當其含有聚烯烴 可僅含有聚烯烴，但是這並非必須的’在本 ，該膜可含有聚烯烴以及非爲聚烯烴的物質 於當多層微多孔膜包含三或更多層的又 該表面層包含（或是實質上由下列物質所組. 物質所組成）：第二個微多孔層物質’而至 層則包含（或是實質上由下列物質所組成或 第一層（例如 層（例如，底 具有平面的頂 軸上，從上面 下。於另一體 中外層（亦稱 孔層物質，而 。於相關的體 係實質上由（ 二層則係實質 於多層微多孔 質上由（或是 層的中間層則 所組成。該膜 時。雖然該膜 發明之範疇內 〇 另一體系中， 成或是由下列 少一層的中間 是由下列物質 -10- 200920595 所組成）：第一個微多孔層物質。 當該多層微多孔膜具有三或更多層時，該多層微多孔 聚烯烴膜具有至少一包含第一個微多孔層物質的層以及至 少一包含第二個微多孔層物質的層。 於一體系中，包含第一個層物質之層的厚度總和通常 係在多層微多孔膜之總厚度的約3%至約90%，或是約 10%至約60%範圍內。 第一個微多孔層物質包含第一個聚丙烯以及第一個聚 乙烯。第二個微多孔層物質包含第二個聚乙烯以及第二個 聚丙烯。多層微多孔聚烯烴膜內之聚乙烯的總量可在約 9_5重量％至約95重量％範圍內（基於多層微多孔聚烯烴 膜的重量）。多層微多孔聚烯烴膜內之聚丙烯的總量可在 約1 · 4重量％至約9 0.5重量％範圍內（基於多層微多孔聚 烯烴膜的重量）。第一個微多孔層物質係以在約50重量％ 至約99重量％ (基於第一個微多孔層物質的重量）範圍內 的第一個聚乙烯量，存在於第一個微多孔層物質內；第一 個聚丙烯係以在約1重量％至約5 0重量％ (基於第一個微 多孔層物質的重量）範圍內的第一個聚丙烯量，存在於第 一個微多孔層物質內；第二個聚乙烯係以約5重量％至約 95重量％ (基於第二個微多孔層物質的重量）範圍內的第 二個聚乙烯量，存在於第二個微多孔層物質內；且第二個 聚丙烯係以在約5重量％至約9 5重量％ (基於第二個微多 孔層物質的重量）範圍內的第二個聚丙烯量，存在於第二 個微多孔層物質內。 -11 - 200920595 第一個與第二個聚乙烯以及第一個與第二 更詳盡說明於下文。 A.第一個聚乙儲 於一體系中，第一個聚乙烯係Mw在約 107、或是約至約5xl06、或是約2xl〇5 範圍的聚乙烯。第一個聚乙烯可爲一或多種的 如，PEI、PE2等等。PE1包含Mw在約lxlO4 範圍內的聚乙嫌。選擇性地，PE1可爲一或多 乙烯（HDPE )、中密度聚乙烯、分枝低密度 是線性低密度聚乙烯。雖未有嚴格限制，但是 烯的M w可在’例如’約1 X i 0 5至約5 X 1 〇 5、或 至約4χ105範圍內。於—體系中，ΡΕι係下列 者：（i)乙烯均聚物或是（ii)乙烯與典型上 相較之下較少量之第三個α-烯烴（諸如，丙烯 己烯-1等等）的共聚物。如是共聚物可採用單 造。 於一體系中’第〜個聚乙烯包含第二個聚 。ΡΕ2包含Mw爲至少約1 xi 〇6的聚乙烯。例 爲超高分子量的聚乙烯（UHMWPE)。於一體 係下列中的至少一者：（i )乙烯均聚物或是（ 第四個α -烯烴（典型上，與乙烯的量相較之· 量較少）的共聚物。該第四個α -烯烴可爲，， 多個丙烯、丁烯-1、戊烯-1、己烯-1、4 -甲基 個聚丙烯將 :1〇4至約lx 至約3 X 1 〇6 聚乙烯，例 至約5 X 1 〇 5 個高密度聚 聚乙烯、或 高密度聚乙 :是約2 X 1 〇 5 中的至少一 與乙稀之量 、丁稀· 1、 點觸媒來製 乙烯，PE2 如，PE2可 系中，PE2 Π )乙烯與 下’其存在 例如’一或 戊靖-1、辛 -12- 200920595 烯-1、乙酸乙烯酯、甲基丙烯酸甲酯、或苯乙烯。雖然未 有嚴格限制，P E 2的M W可在，例如，約1 X 1 0 6至約1 5 X 106、或約lxlO6至約5χ106、或約ΐχΐ〇6至約3><1〇6範圍 內。 在一體系中’第一個聚乙烯同時包含PE1及PE2。在 此情況下，第一個聚乙烯內之p E 2的量可在’例如，〇重 量％至約5 0重量％、或約1重量％至約5 0重量％範圍內（ 基於第一個聚乙稀的重量）。 於一體系中，第一個聚乙烯具有一或多個下列獨立選 擇的特徵： (1) 第一個聚乙烯包含PE1。 (2) 第一個聚乙烯係實質上由或由pE1所組成。 (3) 該PE1係一或多個高密度聚乙烯、中密度聚乙 烯、分枝低密度聚乙烯、或是線性低密度聚乙烯。 (4) PE1係—或多個具有在約ιχ1〇5至約5x1〇5或約 2χ1〇5至約4Xl〇5範圍內之Mw的高密度聚乙烯。 (5) PE1係至少乙烯均聚物或乙烯與第 四個燒烴（選自丙烯、丁烯-1、己烯-1)之共聚物中之 一者。 (6) 第一個聚乙烯同時包含ρΕ1& ρΕ2。 (7 ) ΡΕ2具有在約ιχ106至約15χ1〇6、或選擇性地 約1 X 1 〇6至約5 χ 1 〇 6、或選擇性地約丨χ丨〇 6至約3 χ 1 〇 6範圍 內的Mw。 (8 ) PE2係超高分子量聚乙烯。 -13- 200920595 (9 ) PE2係至少（i )乙烯均聚物或（Η )乙烯與第 四個α-烯烴（選自丙烯、丁烯_；[、己烯之共聚物中之 一者。 (10)第一個聚乙烯所具有的分子量分佈（Mw / Μη )係約5至約3 0 0 '或約5至約1 0 0、或選擇性地約5至 約30。 B.第二個聚乙烯 第二個聚乙烯可包含PE1、PE2、或同時包含PE1及 PE2。當第二個聚乙烯包含pEi及PE2時，第二個聚乙烯 內之PE2的量可在約〇重量％至約5〇重量％、或約1重量 °/〇至約5 0重量％範圍內（基於第二個聚乙烯的重量）。 C·第一個聚丙烯 除了聚乙烯之外，第一個及第二個微多孔層物質還包 含聚丙稀。該聚丙烯可爲，例如，—或多個丙烯均 ¥物或（Π)丙烯與第五個烯烴的共聚物。該共聚物可爲 雜亂（random )或嵌段共聚物。該第五個烯烴可爲，例如 ’一或多個烯烴（諸如，乙烯、丁烯_1、戊烯、己 稀-1、4_甲基戊烯-1、辛烯-1、乙酸乙烯酯、甲基丙烯酸 甲酯、以及苯乙烯）：以及二烯烴（諸如，丁二烯、1,5 -己二燒、1,7-辛二烯、ι，9-癸二烯等等）。共聚物內之第 五個稀烴的量宜在不會對於多層微多孔膜之性質（諸如， if熱性 '耐壓性、耐熱收縮性等）有負面影響的範圍內。 -14- 200920595 例如，第五個烯烴的量可小於1 〇莫耳％ (基於1 00莫耳％ 之整個共聚物）。選擇性地，該聚丙烯可具有一或多個下 列性質：（i )聚丙烯具有的M w在約1 X 1 0 4至約4 X 1 0 6、 或約3xl〇5至約3χ106範圍內；（ii)聚丙嫌具有的Mw/ Μη係在約1·〇1至約1〇〇、或約1.1至約50範圍內；（iii )聚丙烯的立體規正性（tacticity)係整規的（isotactic );(iv)聚丙烯所具有的熔化熱係至少約90J/g; (v )聚丙烯之第二個熔融峰（第二個熔融）係至少約160 °C ;(vi)當在約2；3 0°C的溫度下測量且應變速率爲25秒―1 時所測得之聚丙儲的特如吞比（Trouton’s ratio)係至少 約15 ;及/或（vii )於約23(TC的溫度下且應變速率爲 25秒^時，聚丙烯的拉伸黏度爲至少約5 0,000 Pa sec。選 擇性地，該聚丙烯具有在約1.01至約100、或約1.1至約 50範圍內的Mw / Μη。 D.第二個聚丙烯 聚丙烯宜具有6xl05或更大的重量平均分子量，以及 9〇 J / g或更高的熔化熱△ Hm (根據JIS K7122，藉由示 差掃描熱量分析儀（DSC )所測得的），所具有之分子量 爲1 . 8χ 1 〇6或更大的聚丙烯部分係1 〇質量％或更多。供測 量熔化熱之溫度上升速度宜爲3-20 °C/分鐘，通常爲10 °C /分鐘。由於重量平均分子量小於6x1 05之聚丙烯在聚 乙烯樹脂內具有低的分散性，所以其使用會使得拉伸困難 ’而賦予第二個多孔層的表面大量的微觀粗糙度且使得多 -15- 200920595 層微多孔膜的厚度變動性大。當分子量係1.8x1 06或更大 之聚丙烯的部分係小於1 0% (基於聚丙烯的質量）時，多 層微多孔膜會具有非所要的低熔融性質。當聚丙烯所具有 之熔化熱△ H m係小於9 0 J / g時，結果所得到之多層微 多孔膜具有低熔融性質及滲透性。 聚丙烯之重量平均分子量宜爲6.5xl05或更大，更佳 爲8xl05或更大。雖未有嚴格設限，聚丙烯之Mw / Μη宜 爲1-100。該聚丙烯之熔化熱ΔΗπι可爲90 J/g，宜爲95 J/g或更高’更佳爲100 J/g或更高。分子量分佈，Mw / Μη ’宜爲5或更小，更佳爲4或更小，最佳爲2·5或更 小。 聚丙燃的含量可爲0.01-99.9質量％，宜爲5-95質量 %，更佳爲20-80質量％，最佳爲3 0-70質量％ (基於整個 聚烯烴組成物的質量）。當聚丙烯的量小於0 . 〇 1質量％時 ’熔融溫度不會增加至所企求的程度。當聚丙烯量超過 99_9質量％，多層微多孔膜會具有惡化的厚度均勻度及滲 透性。 只要符合前述重量平均分子量、分子量爲1.8χ106或 更大之部分（由分子量分佈測定得）及熔化熱的條件，對 於聚丙烯的種類雖未有特別的限制，但是，其可爲丙烯均 聚物、丙烯與其他α -烯烴的共聚物或是彼等之混合物， 以均聚物較佳。該共聚物可爲雜亂或嵌段共聚物。於聚丙 稀共聚物內，共聚單體，可包括’例如：乙烯、丁烯_；[、 戊烯-1、己烯-1、4 -甲基戊烯-1、辛烯、乙酸乙烯酯、甲 -16- 200920595 基丙烯酸甲酯、苯乙烯、以及彼等之組合。選擇性地，該 聚丙烯可具有一或多個下列性質：（i)該聚丙烯具有之 Mw在約ΙχΙΟ4至約4χ106、或約6xl05至約3χ106的範圔 內；（Π )該聚丙烯具有之Mw / Μη在約1.01至約1〇0、 或是約1.1至約50的範圍內；（iii)該聚丙嫌之立體規 正性係整規的；（iv )該聚丙烯所具有之熔化熱係至少爲 約90】/g; (v)該聚丙烯所具有之熔融峰（第二個熔融 )係至少約1 6 0 °C ; ( v i )當在約2 3 0 °C的溫度下測量且 應變速率爲25秒^時所測得之聚丙烯的特如吞比（ Trouton’s ratio)係至少約 15;及 / 或（vii)於約 23〇°C 的溫度下且應變速率爲2 5秒_1時，聚丙烯的拉伸黏度爲 至少約 5 0,00 0 Pa sec ° 聚丙嫌之Mw及Μη可藉由，例如，GPC，於下列的 條件下測量得。測量裝置：A11 i a n c e 2 0 0 0 G P C，購自 Waters Corp_ ;管柱：三支 PL Gel 混合-B，購自 Polymer Laboratories。管柱溫度：145 °C ，溶劑（移動相）： 1，2,4-三氯基苯，以0.1重量％ BHT，6 g/4L予以安定。 溶劑流速：1 ·〇 ml /分鐘。試樣濃度：0.25 mg / mL (於 17 5 °C下溶解1小時）。注射量：3 0 0 /z 1。偵測器： Differential Refractometer (微差折射儀），購自 Waters Corp.。校正曲線：使用預先測定得之轉換常數，由一組 單分散、標準聚苯乙烯試樣的校正曲線所產生得的。 聚丙烯之熔化熱△ Hm可根據jis K7 1 22，如下文所述 地測量得··於示差掃描熱量分析儀（D S C - S y s t e m 7，購自 -17- 200920595200920595 IX. INSTRUCTIONS OF THE INVENTION [Technical Field] The present invention relates to a multilayer microporous polyolefin film having suitable permeability, pin puncture strength, shutdown temperature, shutdown speed, melting temperature and Thickness uniformity. The present invention also relates to a battery separator formed of, for example, a multilayer microporous membrane, and a battery comprising the separator. Another aspect of the present invention relates to a method of producing the multilayer microporous polyolefin film, a method of producing a battery such as a film as a separator, and a method using a battery. [Prior Art] The porous polyolefin film can be used, for example, as a battery separator for primary and secondary lithium batteries, lithium polymer batteries, nickel hydrogen batteries, nickel cadmium batteries, nickel zinc batteries, silver zinc batteries, and the like. When microporous polyolefin membranes are used in battery separators (especially lithium ion battery separators), membrane performance can significantly affect the properties, productivity, and safety of the battery. Therefore, the microporous polyolefin film should have appropriate mechanical properties, heat resistance, permeability, dimensional stability, shutdown properties, melting properties, and the like. As is well known, batteries should have a relatively low shutdown temperature and a relatively high melting temperature to improve battery safety, especially during manufacturing, charging, recharging, use, and/or storage. For batteries exposed to high temperatures. Improvements in the permeability of the separator generally result in an improvement in the storage capacity of the battery. The high speed shutdown speed is required to improve battery safety, especially when the battery is operated under overcharge conditions. The improved pin compressive strength is intended to be -5-200920595 because the roughness of the electrode of the battery causes a short circuit to occur during the manufacturing period. The improved thickness uniformity is desirable because of variations in thickness which can cause manufacturing difficulties when the film is wound around the core. Variations in thickness can also cause anisotropic temperature variations within the battery. This can result in battery hot spots (higher temperature areas) when the separator is relatively thin. In general, a microporous film containing only polyethylene (that is, a film composed of or consisting of polyethylene) has a low melting temperature, and a microporous film containing only polypropylene has High shutdown temperature. Therefore, a microporous film comprising polyethylene and polypropylene as main components has been proposed as an improved battery separator. Therefore, a microporous film formed of a polyethylene resin and a polypropylene resin, and a multilayer microporous film comprising polyethylene and polypropylene are provided. For example, JP 7-216118 A discloses a battery separator having an appropriate shutdown temperature and mechanical strength. This patent application discloses a battery separator comprising a multilayer porous film having two microporous layers. Both layers may contain polyethylene and polypropylene, but the relative amounts are different. For example, in the first microporous layer, the percentage of polyethylene is 〇 weight / ❶ to 20% by weight 'and in the second microporous layer is 21% by weight to 60% by weight (based on polyethylene and polypropylene) Total weight). The total amount of polyethylene in the film (i.e., the two microporous layers) is from 2% by weight to 40% by weight based on the weight of the multilayer microporous film. J P 1 0 - 1 9 5 2 1 5 A reveals a relatively thin battery separator with acceptable closure and pin-pulling characteristics. The term "pin pull" refers to the relative ease of pulling a metal pin from a laminate of a separator, a cathode sheet and an anode sheet. The laminate is wound around a pin to form a ring. Laminate. The multilayer porous film contains polyethylene and polypropylene, but differs in relative amounts. The percentage of polyethylene in the inner layer is from 重量% by weight to 20% by weight, and in the outer layer is from 61% by weight to 100% by weight (based on the total weight of polyethylene and polypropylene). JP 10-279718 A discloses a separator which is designed to prevent an unacceptably large temperature increase in a lithium battery when the battery is overcharged. The separator is formed of a multilayer porous film made of polyethylene and polypropylene, and the relative amounts of polyethylene and polypropylene in each layer are different. The film has a polyethylene-deficient layer having a polyethylene content of from 〇% by weight to 20% by weight (based on the weight of the polyethylene-deficient layer). The second layer is a polyethylene-rich layer containing 0.5% by weight or more of a polyethylene having a melt index of 3 or more and having a polyethylene content of 61% by weight to 100% by weight (based on the rich The weight of the polyethylene layer). It is also necessary to further improve the permeability of the microporous polyolefin film, the pin pressure resistance, and the shutdown speed. Further, there is a need to further improve the thickness uniformity of the microporous polyolefin film, and to reduce the possibility of short circuits when used as a battery separator. SUMMARY OF THE INVENTION In one system, the present invention is directed to a multilayer microporous membrane comprising: a first layer of material comprising a first polyethylene and a first polypropylene 200920595 olefin and a second layer a substance comprising a second polyethylene and a diene, the second polypropylene having a weight average molecular weight of 6.5 χ 105 or a heat of fusion of 95 J/g or more, and having a molecular weight of U greater The polypropylene portion accounts for 10% by mass or more (based on the mass of the polypropylene). The multilayer film can comprise, for example, a first pore layer comprising a first microporous layer material; and a second microparticle comprising a second microporous layer material. For example, the multilayer film of the patent application may include: a first microporous layer comprising a first microporous layer material microporous layer containing a first microporous layer material; and a first porous layer containing a second microporous layer material, the second microsystem being located between the first and third microporous layers. In an alternative form, the multilayer microporous membrane may comprise a microporous layer comprising a second microporous layer material; a third layer comprising a second microporous layer material; and a second micro More than one contains the first microporous layer material, and the second microporous layer is between one and the third microporous layer. In another system, the present invention is directed to a method of making a microporous method comprising: (1) kneading a first polyethylene resin, a first polypropylene tree, and a first processing solvent to form the first a polyethylene solution 'the first polyethylene resin and the first polypropylene resin together with a polyolefin composition; and wherein the first polyolefin comprises a polypropylene larger than Χίο6 or a second microporous layer Circumference 1: The third microporous layer: the first microporous layer, the square fat located in the membrane, wherein the amount of the first polyethylene -8-200920595 constituting the first is at least about 80 % by weight (based on the weight of the first polyolefin composition): and (2) twisting the second polyethylene resin, the second polypropylene resin, and the second processing solvent to form a second polyolefin a solution wherein the second polyethylene resin and the second polypropylene resin together form a second polyolefin composition; and wherein the amount of the second polyethylene in the second polyolefin composition is at least about 50% by weight (based on the second poly The weight of the hydrocarbon composition); the second polypropylene resin has a weight average molecular weight of 6.5 x 10 s or more and a heat of fusion of 95 J/g or more, and has a second polypropylene portion having a molecular weight of 1.8 X 106 or more. The system accounts for 10% by mass or more (based on the mass of the second polypropylene resin). In one system, the invention further comprises: (3) extruding at least a portion of the first polyolefin solution through the die and coextruding at least a portion of the second polyolefin solution to form a multilayer extrudate, (4) The multilayer extrudate is cooled to form a multilayer sheet, (5) removing at least a portion of the processing solvent from the multilayer sheet to form a solvent-removed sheet, and (6) from the sheet At least a portion of any volatile species is removed to form a multilayer microporous membrane. In still another system, the present invention is directed to a battery comprising an anode, a cathode, and an electrolyte, and a multilayer film of the foregoing system, wherein the multilayer film isolates at least the anode from the cathode. This battery can be used as a source of charge or a reservoir. -9- 200920595 DETAILED DESCRIPTION OF THE INVENTION [1] Composition and structure of multilayer microporous polyolefin film In a system, a multilayer microporous film comprises two layers. The upper layer) comprises a first microporous layer material and the second layer comprises a second microporous layer material. For example, the film layer (when viewed at right angles to the transverse and mechanical directions of the film), while viewed from the top layer, the bottom layer is hidden in the system, the multilayer microporous film comprising three or more layers , as the "surface" or "skin" layer), the intermediate layer comprising at least one of the first micro-multiple layers comprises a second microporous layer material system, and when the multilayer microporous membrane comprises two layers, the first layer is either The first microporous layer material consists of, and the first consists of (or consists of) a second microporous material. In a related system in which the film comprises three or more layers, the outer layer is composed of the first microporous layer material, and at least one of the substances substantially consisting of (or consisting of) the second microporous layer may be referred to as "Polyolefin film" 'when it contains a polyolefin, it may contain only polyolefin, but this is not essential. Here, the film may contain a polyolefin and a non-polyolefin material when the multilayer microporous film contains three or more. The surface layer of the layer further comprises (or consists essentially of: the substance: a second microporous layer material) and the layer comprises (or consists essentially of or consists of: (for example, a layer (for example, the bottom has a flat top axis, from the top down. In the other body, the outer layer (also known as the pore layer material, and the related system is essentially composed of (the second layer is substantially multi-layered microporous) The upper layer (or the intermediate layer of the layer is composed of the film. Although the film is in the scope of the invention, in another system, the middle or the lower layer is composed of the following substances - 10 200920595) :First a porous layer material. When the multilayer microporous membrane has three or more layers, the multilayer microporous polyolefin membrane has at least one layer comprising a first microporous layer material and at least one material comprising a second microporous layer material In a system, the sum of the thicknesses of the layers comprising the first layer of material is typically in the range of from about 3% to about 90%, or from about 10% to about 60%, of the total thickness of the multilayer microporous membrane. A microporous layer material comprises a first polypropylene and a first polyethylene. The second microporous layer material comprises a second polyethylene and a second polypropylene. Polyethylene in the multilayer microporous polyolefin film The total amount may range from about 9 to 5% by weight to about 95% by weight based on the weight of the multilayer microporous polyolefin film. The total amount of polypropylene in the multilayer microporous polyolefin film may range from about 1.4% by weight to about 9 in the range of 0.5% by weight (based on the weight of the multilayer microporous polyolefin film). The first microporous layer material is in the range of from about 50% by weight to about 99% by weight (based on the weight of the first microporous layer material) The first amount of polyethylene inside, exists In the first microporous layer material; the first polypropylene is in an amount of from about 1% by weight to about 50% by weight (based on the weight of the first microporous layer material), Existing in the first microporous layer material; the second polyethylene is present in an amount of from about 5% by weight to about 95% by weight (based on the weight of the second microporous layer material) In the second microporous layer material; and the second polypropylene is in a second polypropylene amount in the range of from about 5% by weight to about 9% by weight based on the weight of the second microporous layer material , present in the second microporous layer material. -11 - 200920595 The first and second polyethylenes, as well as the first and second, are described in more detail below. A. The first polyether is stored in a system. The first polyethylene Mw has a polyethylene in the range of about 107, or about to about 5 x 106, or about 2 x 10 〇5. The first polyethylene may be one or more of, for example, PEI, PE2, and the like. PE1 contains Mw in the range of about lxlO4. Alternatively, PE1 may be one or more ethylene (HDPE), medium density polyethylene, and branched low density linear low density polyethylene. Although not strictly limited, the Mw of the alkene may range from >, for example, from about 1 X i 0 5 to about 5 X 1 〇 5, or to about 4 χ 105. In the system, ΡΕι is the following: (i) an ethylene homopolymer or (ii) a third amount of a third olefin (e.g., propylene hexene-1, etc.) having a smaller amount than ethylene. Copolymer. For example, the copolymer can be produced by itself. In a system, the first polyethylene contains a second poly. ΡΕ 2 comprises a polyethylene having a Mw of at least about 1 xi 〇6. An example is ultra high molecular weight polyethylene (UHMWPE). At least one of the following: (i) an ethylene homopolymer or a copolymer of (a fourth alpha-olefin (typically less than the amount of ethylene). The α-olefin may be, a plurality of propylene, butene-1, pentene-1, hexene-1, 4-methylpolypropylene: 1〇4 to about 1x to about 3 X 1 〇6 polyethylene , to about 5 X 1 〇 5 high-density polyethylene, or high-density polyethylene: at least one of about 2 X 1 〇 5 with ethylene, butyl 1 , catalyst to produce ethylene For example, PE2 can be, for example, PE2 Π) ethylene and the following 'existing such as 'one or pentacene-1, xin-12-200920595 ene-1, vinyl acetate, methyl methacrylate, or styrene. Although not strictly limited, the MW of PE 2 may range, for example, from about 1 X 1 0 6 to about 1 5 X 106, or from about 1 x 10 6 to about 5 χ 106, or from about ΐχΐ〇 6 to about 3 > < 1 〇 6 Inside. In a system, the first polyethylene contains both PE1 and PE2. In this case, the amount of p E 2 in the first polyethylene may range from '% by weight to about 50% by weight, or from about 1% by weight to about 50% by weight (based on the first The weight of polyethylene)). In a system, the first polyethylene has one or more of the following independently selected features: (1) The first polyethylene comprises PE1. (2) The first polyethylene system consists essentially of or consists of pE1. (3) The PE1 is one or more high density polyethylene, medium density polyethylene, branched low density polyethylene, or linear low density polyethylene. (4) PE1 is a high-density polyethylene having a Mw in the range of from about 1 χ1〇5 to about 5x1〇5 or from about 2χ1〇5 to about 4Xl〇5. (5) PE1 is at least one of ethylene homopolymer or a copolymer of ethylene and a fourth hydrocarbon (selected from propylene, butene-1, hexene-1). (6) The first polyethylene contains both ρΕ1&ρΕ2. (7) ΡΕ2 has a range of from about ιχ106 to about 15χ1〇6, or alternatively from about 1 X 1 〇6 to about 5 χ 1 〇6, or alternatively from about 丨χ丨〇6 to about 3 χ 1 〇6 Mw inside. (8) PE2 is an ultra high molecular weight polyethylene. -13- 200920595 (9) PE2 is at least (i) an ethylene homopolymer or (Η) ethylene and a fourth α-olefin (one selected from the group consisting of propylene, butene-; [hexene]. (10) The first polyethylene has a molecular weight distribution (Mw / Μη) of from about 5 to about 30,000 or from about 5 to about 1, or alternatively from about 5 to about 30. B. The polyethylene second polyethylene may comprise PE1, PE2, or both PE1 and PE2. When the second polyethylene comprises pEi and PE2, the amount of PE2 in the second polyethylene may range from about 〇% to About 5% by weight, or about 1% by weight to about 50% by weight (based on the weight of the second polyethylene) C. The first polypropylene except polyethylene, first and The two microporous layer materials further comprise polypropylene. The polypropylene may be, for example, a copolymer of propylene or (propylene) propylene and a fifth olefin. The copolymer may be random. Or a block copolymer. The fifth olefin may be, for example, 'one or more olefins (such as ethylene, butene-1, pentene, hexa-1, 4-methylpentene-1, octene) -1, Acid vinyl ester, methyl methacrylate, and styrene): and diolefins (such as butadiene, 1,5-hexane, 1,7-octadiene, iota, 9-decadiene, etc.) The amount of the fifth rare hydrocarbon in the copolymer is preferably in a range which does not adversely affect the properties of the multilayer microporous film such as if heat 'pressure resistance, heat shrinkage resistance, etc. - 14 - 200920595 For example, the amount of the fifth olefin may be less than 1 〇 mol% (based on 100% by mole of the entire copolymer). Alternatively, the polypropylene may have one or more of the following properties: (i) polypropylene has The M w is in the range of from about 1 X 1 0 4 to about 4 X 1 0 6 , or from about 3 x 1 〇 5 to about 3 χ 106; (ii) the polypropylene has a Mw/Μη system of from about 1·〇1 to about 1〇. 〇, or in the range of about 1.1 to about 50; (iii) the stereotacticity of the polypropylene is isotactic; (iv) the polypropylene has a heat of fusion of at least about 90 J/g; The second melting peak of polypropylene (second melting) is at least about 160 ° C; (vi) measured at a temperature of about 2; 30 ° C and measured at a strain rate of 25 sec -1 Polypropylene storage The tensile strength of the polypropylene is at least about 5,000 Pa sec when the Trouton's ratio is at least about 15; and/or (vii) is about 23 (at a temperature of TC and the strain rate is 25 seconds). Optionally, the polypropylene has a Mw / Μη in the range of from about 1.01 to about 100, or from about 1.1 to about 50. D. The second polypropylene polypropylene preferably has a weight average molecular weight of 6 x 105 or greater, and 9 〇J / g or higher heat of fusion Δ Hm (measured by differential scanning calorimetry (DSC) according to JIS K7122), having a molecular weight of 1.8 χ 1 〇 6 or more Part of the system is 1% by mass or more. The temperature rise rate for measuring the heat of fusion is preferably 3-20 ° C / min, usually 10 ° C / min. Since the polypropylene having a weight average molecular weight of less than 6×10 5 has low dispersibility in the polyethylene resin, its use makes the stretching difficult, and the surface of the second porous layer is given a large amount of micro-roughness and makes the multi--15- 200920595 The thickness of the layer microporous film is large. When the portion of the polypropylene having a molecular weight of 1.8 x 106 or more is less than 10% (based on the mass of polypropylene), the multilayer microporous film may have an undesirable low melting property. When the polypropylene has a heat of fusion ΔH m of less than 90 J / g, the resulting multilayer microporous film has low melting properties and permeability. The weight average molecular weight of the polypropylene is preferably 6.5 x 105 or more, more preferably 8 x 10 5 or more. Although not strictly limited, the Mw / Μη of polypropylene should be 1-100. The polypropylene may have a heat of fusion ΔΗπι of 90 J/g, preferably 95 J/g or more, more preferably 100 J/g or more. The molecular weight distribution, Mw / Μη ' is preferably 5 or less, more preferably 4 or less, most preferably 2. 5 or less. The content of the polypropylene fuel may be from 0.01 to 99.9% by mass, preferably from 5 to 95% by mass, more preferably from 20 to 80% by mass, most preferably from 30 to 70% by mass based on the mass of the entire polyolefin composition. When the amount of polypropylene is less than 0. 〇 1% by mass, the melting temperature does not increase to the extent desired. When the amount of polypropylene exceeds 99 - 9 mass%, the multilayer microporous film may have deteriorated thickness uniformity and permeability. The propylene homopolymer is not particularly limited as long as it conforms to the aforementioned weight average molecular weight, a molecular weight of 1.8 χ 106 or more (measured by molecular weight distribution), and heat of fusion. However, it may be a propylene homopolymer. A copolymer of propylene and another α-olefin or a mixture thereof is preferably a homopolymer. The copolymer can be a clutter or block copolymer. In the polypropylene copolymer, the comonomer may include 'eg, ethylene, butene _; [, pentene-1, hexene-1, 4-methylpentene-1, octene, vinyl acetate, A-16- 200920595 based on methyl acrylate, styrene, and combinations thereof. Alternatively, the polypropylene may have one or more of the following properties: (i) the polypropylene has a Mw in the range of from about 4 to about 4 χ 106, or from about 6 x 105 to about 3 χ 106; (Π) the polypropylene has Mw / Μη is in the range of about 1.01 to about 1 〇 0, or about 1.1 to about 50; (iii) the polystyrene is stereoregular; (iv) the heat of fusion of the polypropylene The system has a melting peak (second melting) of at least about 160 ° C; (vi) when measured at a temperature of about 325 ° C. And the Trouton's ratio of the polypropylene measured at a strain rate of 25 seconds is at least about 15; and / or (vii) at a temperature of about 23 ° C and the strain rate is 25 seconds. _1, the polypropylene has a tensile viscosity of at least about 50,000 kPa. The polypropylene Mw and Μη can be measured by, for example, GPC under the following conditions. Measuring device: A11 i a n c e 2 0 0 0 G P C, purchased from Waters Corp_; column: three PL Gel Mix-B, available from Polymer Laboratories. Column temperature: 145 ° C, solvent (mobile phase): 1,2,4-trichlorobenzene, stabilized with 0.1% by weight of BHT, 6 g/4L. Solvent flow rate: 1 · 〇 ml / minute. Sample concentration: 0.25 mg / mL (dissolved at 17 5 ° C for 1 hour). Injection volume: 3 0 0 /z 1. Detector: Differential Refractometer, available from Waters Corp. Calibration curve: A pre-measured conversion constant generated from a calibration curve for a set of monodisperse, standard polystyrene samples. The heat of fusion ΔHm of polypropylene can be measured according to jis K7 1 22 as described below. · Differential Scanning Thermal Analyzer (D S C - S y s t e m 7, purchased from -17- 200920595
Perkin Elmer Inc.)的試樣容槽（sample holder)內 氮氣氛、190 °C下，對PP試樣進行熱處理10分鐘，. °C /分鐘的速度，予以冷卻至40°C，保持在4(TC下 鐘，並且以10 °C /分鐘的速度，加熱至190 °C。如第 所示者，通過由85°C及175°C下之溫度上升過程所得 DSC曲線（熔融曲線）上的點之直線可畫爲基線，且 量可由基線與D S C曲線所圍繞的斜線部分，區域S 1 得。用試樣的重量（單位：g )除以熱的量（單位：J 來決定熔化熱ΔΗιη (單位：J/g)。 所具有之分子量爲1.8xl06或更小之聚丙烯部分 分比（基於質量）可如下測量得。可測量第2圖內之 曲線及基線索圍繞之斜線部分，區域S2，來測定整 丙烯試樣的量。可測量第 3圖內的區域 S 3，來決定 有之分子量係1·8χ106或更大之部分的量。所具有之 量爲1.8x1 〇6或更大之部分的百分比係由（S3/S2) (質量％ )計算得。 [2]用於製造多層微多孔聚烯烴膜的物質 Α.用於製造第一個微多孔層物質的聚合物樹脂 於一體系中，第一個微多孔層物質係由第一個聚 ί容液製得的。第一個聚烯烴溶液包含第一個聚烯烴組 以及第一個加工溶劑。由於此過程係產生多層微多孔 戶斤以’該加工溶劑亦稱作爲稀釋劑或膜形成溶劑。用 胃第一個聚烯烴組成物的樹脂將更加詳盡敘述於下文 ，在 ίλ 1 0 2分 1圖 到的 熱的 計算 )， 的百 GPC 個聚 所具 分子 xl 00 烯烴 成物 膜， 於製 -18- 200920595 (1)第一個聚乙烯樹脂 於一體系中，第一個聚乙烯樹脂包含第一個聚乙烯’ 其中第一個聚乙烯係如前文之段落π]部分所述者。例如’ 第一個聚乙烯樹脂可爲具有較UHMWPE (諸如’ HDPE ) 爲低之Mw的聚乙烯樹脂與UHMWPE樹脂的混合物。 第一個聚乙烯樹脂內之聚乙烯的分子量分佈（Mw / Μη )並未有嚴格限制。Mw / Μη乃分子量分佈的衡量標準 ，該値愈大，表示分子量分佈愈廣。雖未有嚴格設限，第 一個聚乙烯樹脂內的聚乙烯Mw / Μη可在約5至約300的 範圍內，或在約5至約1 〇 〇的範圍內，或在約5至約3 0 的範圍內。當Mw/Mn小於5時，會更難以擠壓出第一個 聚乙嫌樹脂。另一方面，當Mw / Μη大於300時，則會更 難以產生相對較強的多層微多孔膜。多階段的聚合法可用 來得到所企求之第一個聚乙烯樹脂內的Mw / Μη。例如， 可採用二階段聚合方法’於第—個階段形成相對較高分子 量的聚合物成份，且於第二個階段形成相對較低分子量的 聚合物成份。雖然並非必要的，但是，例如，當第一個聚 乙烯樹脂包含Ρ Ε 1時，則可採用此方法。當第一個聚乙烯 樹脂包含ΡΕ1及ΡΕ2時，所企求之聚乙烯樹脂的Mw / Μη 比例可藉由調整第一個及第二個聚乙烯之相對分子量及相 對量，來選擇。 (2)第一個聚丙烯樹脂 -19- 200920595 除了第一個聚乙烯樹脂之外，第一個聚烯 包含了第一個聚丙烯樹脂。於一體系中，第一 脂包含了第一個聚丙烯，其中該第一個聚丙烯 段落π]中所記載者。第一個聚丙烯樹脂可爲， 多個（i)丙嫌均聚物或（ii)丙烯與第五個烯 。該共聚物可爲雜亂或嵌段共聚物。該第五個 例如，一或多個α -烯烴（諸如，乙烯、丁烯·: 己嫌-1、4 -甲基戊烯_丨、辛烯_丨、乙酸乙烯酯 酸甲醋、以及苯乙烯等等）：以及二烯烴（諸 、1，5-己—烯、ΐ，7-辛二烯、丨，9_癸二烯等等） 之第五個烯烴的量應在不會對於多層微多孔膜 如’耐熱性、耐壓性、耐熱收縮性等）有負面 內。例如’第五個嫌烴的量可小於1 〇莫耳％ ( 耳％之整個共聚物）。 雖然未有嚴格限制，第一個聚丙烯樹脂內 Mw可在’例如’約ιχ1〇4至約4χ1〇6範圍內 1 05至約3 X 1 0 6範圍內。雖未有嚴格限制，第 樹脂內之聚丙烯的分子量分佈（Mw / Μη)可宅 約1 00範圍內，或約i」至約5〇範圍內。 (3 )配方 第一個聚烯烴溶液內之加工溶劑的量可在 2 5重量％至約9 9重量％範圍內（基於第一個聚 重里）。於一體系中，第一個聚烯烴組成物內 烴組成物還 個聚丙烯樹 係如前文的 例如，一或 烴的共聚物 烯烴可爲， ί、戊嫌-1、 、甲基丙烯 如，丁二烯 。共聚物內 之性質（諸 影響的範圍 基於100莫 之聚丙烯的 ，或是約3Χ 一個聚丙嫌 匕約1 · 0 1至 ，例如，約 烯烴溶液的 之第一個聚 -20- 200920595 乙嫌樹脂的量可在，例如，約5 0重量％至約9 9重量％範 圍內（基於第一個聚烯烴組成物的重量）。第一個聚稀烴 組成物的剩餘部分爲第一個聚丙烯。 Β.用於製造第二個微多孔層物質的聚合物樹脂 於一體系中，第二個微多孔層物質係由第二個聚稀烴 溶液（其選擇係與第一個聚烯烴溶液無關的）所製得的。 第二個聚烯烴溶液包含了第二個聚烯烴組成物及第二個加 工溶劑（此溶劑可與第一個加工溶劑相同）。如同在第一 個聚烯烴溶液的情況下，第二個加工溶劑可稱作爲第二個 膜形成溶劑或第二個稀釋劑。於一體系中，第二個聚烯烴 組成物包含第二個聚乙烯樹脂及第二個聚丙烯樹脂。第二 個聚乙烯樹脂可包含前文之段落[1]所記載的第二個聚乙烯 樹脂。第二個聚丙烯樹脂包含前文之段落[1]所記載的第二 個聚丙烯。 第二個聚烯經溶液內之加工溶劑的量可在約2 5重量％ 至約99重量％範圍內（基於第二個聚烯烴溶液的重量）。 於一體系中，第二個聚烯烴組成物內之第二個聚乙烯樹脂 之量可在，例如，約5重量％至約95重量％範圍內（基於 第二個聚烯烴組成物的重量）。第二個聚烯烴組成物的剩 餘部分可爲第二個聚丙烯。 C .第三個聚烯烴 雖非必要的，第一個及第二個聚烯烴組成物各可進一 -21 - 200920595 步包含選自下列的第三個聚烯烴：聚丁烯-1、聚戊烯-i、 聚-4-甲基戊烯-1、聚己烯-1、聚辛烯-1、聚乙酸乙烯酯、 聚甲基丙烯酸甲酯、聚苯乙烯以及乙烯烯烴共聚物（ 除了乙烯-丙烯共聚物之外）。於使用了第三個聚烯烴的 體系中，該第三個聚烯烴可，例如，具有在約lxio4至約 4xl〇6範圍內的Mw。除了第三個烯烴之外，第一個及/或 第二個聚烯烴組成物亦可進一步包含聚乙烯蠟，例如，具 有在約lxlO3至約lxl〇4範圍內之Mw者。在使用時，此 等物種所出現之量應小於會使得多層微多孔膜之所要性質 (例如，熔融、關閉等等）惡化的量。當第三個聚烯烴係 下列一或多者時：聚丁烯-1、聚戊烯-1、聚-4-甲基戊烯-1 、聚己烯-1、聚辛烯-1、聚乙酸乙烯酯、聚甲基丙烯酸甲 酯、以及聚苯乙烯，該第三個聚烯烴無需爲均聚物，但是 可爲含有其他α -烯烴的共聚物。 多層微多孔膜通常包含用於形成聚烯烴溶液的聚烯烴 。亦可能有少量清洗溶劑及/或加工溶劑出現，該量通常 係小於1重量％ (基於微多孔聚烯烴膜的重量）。在加工 過程中，可能會發生少量的聚烯烴分子量降低，但是此乃 可接受的。於一體系中，若在加工過程中有發生分子量的 降低，則會造成膜內聚烯烴的Mw/Mn數値與第一個或第 二個聚稀烴溶液的M w / Μ η相差不大於約5 0 %，或不大於 約1 %，或是不大於約0. 1 %。 [3]多層微多孔聚烯烴膜的製造方法 -22- 200920595 於一體系中，該微多孔聚烯烴膜乃雙層膜。於另一體 系中，該微多孔聚烯烴膜具有至少三層。爲了簡潔起見， 微多孔聚烯烴膜的製造主要將以雙層及三層膜來說明，但 是，習於此藝之士可認知到，相同的技術可適用於膜或具 有至少四層之膜的製造。 於一體系中，三層微多孔聚烯烴膜包含構成微多孔聚 烯烴膜之外層的第一及第三層的微多孔層，以及位於第一 及第三層之間（且選擇性地與彼等呈平面接觸）的第二層 。於一體系中，第一及第三層係由第一個聚烯烴溶液所產 生，而第二層（內層）係由第二個聚烯烴溶液所產生的。 於另一體系中，第一及第三層係由第二個聚烯烴溶液所產 生，且第二層係由第一個聚烯烴溶液所產生。 A.第一個製造方法 第一個製造多層膜的方法包含下列步驟：（1)將第 一個聚烯烴組成物及一膜形成溶劑倂合（例如，藉由熔融 摻合），來製備第一個聚烯烴溶液，（2)將第二個聚烯 烴組成物與第二個膜形成溶劑倂合，來製備第二個聚烯烴 溶液，（3)令第一個及第二個聚烯烴溶液（宜爲同時） 擠壓通過至少一個模具，而形成一擠出物，（4)將該擠 出物冷卻，而形成冷卻的擠出物’例如，多層凝膠狀片狀 物，（5 )自該多層片狀物移除膜形成溶劑，而形成已去 除溶劑的片狀物’以及（6 )將該已去除溶劑的凝膠狀片 狀物乾燥’以移除若有存在的任何揮發性物種，以形成多 -23- 200920595 層微多孔聚烯烴膜。視需要，可在步驟（4)與（5)之間 ，進行選擇性的拉伸步驟（7 )、以及選擇性的熱溶劑處 理步驟（8 )。若需要，在步驟（6 )之後，可進行拉伸多 層微多孔膜的選擇性步驟（9 )、選擇性熱處理步驟（1 0 )、使用游離輻射之選擇性的交聯步驟（1 1 ) '以及選擇 性的親水性處理步驟（1 2 )等等。選擇性步驟的順序並沒 有嚴格限制。 (1 )第一個聚烯烴溶液的製備 第一個聚烯烴組成物包含前文所述的聚稀烴樹脂’其 可與適當的膜形成溶劑，例如，藉由乾燥混合或熔融慘合 ，倂合而產生第一個聚烯烴溶液。選擇性地’第一個多稀 烴溶液可含有各種添加劑’諸如，下列一或多者：抗氧化 劑、微細的氧化矽粉末（形成孔的物質）等等’先決條件 是··彼等所使用的濃度範圍不會顯著降低該多層微多孔聚 烯烴膜之所企求的性質。 第一個加工溶劑（亦即，第一個膜形成溶劑）宜爲在 室溫下爲液態的溶劑。雖然不願受縛於任何理論或模式， 吾人相信’使用液態溶劑來形成第一個聚烯烴溶液’有可 能在相對較高的拉伸倍率下，進行該凝膠狀片狀物的拉伸 。於一體系中’第一個膜形成溶劑可爲下列中的至少一者 :脂族、脂環或芳族烴類’諸如’壬烷、癸烷、十氫萘、 對二甲苯、十一烷、十二烷、液態石蠟等等；沸點與前述 烴類相當之礦物油餾出物；以及室溫下的駄酸醋液體’諸 -24- 200920595 如，酞酸二丁酯、酞酸二辛酯等等。於欲得到具有安定液 態溶劑含量之多層凝膝狀片狀物的體系中，可單獨使用非 揮發性的液態溶劑（諸如，液態石蠟）或將其與其他溶劑 倂用。選擇性地，可使用在熔融摻合狀態下可與聚乙烯互 溶但在室溫下呈固態的溶劑，其可單獨使用或與液態溶劑 倂用。如是固態溶劑可包括，例如，十八烷醇、十六烷醇 、石蠟等等。雖然未有嚴格限制，當溶液未含有液態溶劑 時，欲平均地拉伸凝膠狀片狀物或所得到之膜，將會更加 困難。 液態溶劑的黏度並非具有決定性的參數。例如，液態 溶劑的黏度可在約30 cSt至約500 cSt、或約30 cSt至約 200 cSt範圍內（25 °C )。雖然其並非具有決定性的參數 ，但是當其在25 °C下的黏度小於約30 cSt時，要預防聚 烯烴溶液的起泡現象（這會導致摻合困難），將會更加困 難。另一方面，當其黏度大於約500 cSt時，要自多層微 多孔聚烯烴膜去除液態溶劑，將會更加困難。 於一體系中，用於產生第一個聚烯烴組成物的樹脂等 等係於，例如，雙輥擠壓機或混合器內，進行乾燥混合或 熔融摻合。例如，習用的擠壓機（或混合器或是混合器-擠壓機），諸如，雙輥擠壓機可用來將樹脂等等倂合，而 形成第一個聚烯烴組成物。可在方法過程中的任何便利時 點上，將膜形成溶劑添加至該聚烯烴組成物（或是可選擇 添加至用於產生聚烯烴組成物的樹脂）。例如’於第一個 烯烴組成物與第一個膜形成溶劑係熔融摻合時，該溶劑可 -25- 200920595 在（i )開始熔融摻合之前，（π )在第一個聚烯烴組.成物 的溶融摻合期間’或是（i i i )熔融摻合之後的任何點，添 加至聚燦烴組成物（或其組成份），例如，藉由於第二個 if®機或位於用來熔融摻合該聚烯烴組成物之擠壓機區下 游的擠壓機區域內’將第一個膜形成溶劑添加至已熔融摻 合或部分溶融摻合的聚烯烴組成物來進行。 # $ m '熔融摻合時，對於熔融摻合溫度係未有嚴格限 制例如’第一個聚燦烴溶液之熔融摻合溫度可在約較第一 個聚乙嫌樹脂之熔點丁1111高1(TC之溫度至約較Tmi高120 °C之溫度範圍內。爲了簡潔起見，如是之範圍可表示爲 Tim + lOt：至Tm〗 + 12(rc。於第一個聚乙烯樹脂具有之熔點 係約1 3 0 °C至約1 40°C的體系中，該熔融摻合溫度可在約 1 4 0 °C至約2 5 0 °C範圍內，或約1 7 0 °C至約2 4 01：範圍內。 當使用擠壓機（諸如，雙輥擠壓機）來進行熔融摻合 時’該輥的參數係未有嚴格限制的。例如，該輥的特徵可 在於：雙輕擠壓機之輥長度L與輥直徑D的比例L / D可 在’例如，約20至約1〇〇範圍內、或約35至約70範圍 內。雖然對此參數並未有嚴格限制，但是當L / D小於約 20時’熔融摻合將會更加困難，且當l/D大於約100時 ，可能需要更快的擠壓機速度，以預防聚烯烴溶液於雙輥 擠壓機內的滯留時間過長（♦這會導致非所要的分子量降低 )。雖非具有決定性的參數，但是雙輥擠壓機的擠壓筒（ 或孔）可具有，例如，在約40 mm至約1〇〇 mm範圍內的 內徑。 -26- 200920595 第一個聚烯烴溶液內之第一個聚烯烴組成物的量並未 有嚴格設限。於一體系中，第一個聚烯烴溶液內之第一個 聚烯烴組成物的量可在約1重量％至約75重量％ (基於聚 烯烴溶液的重量）範圍內，例如，約2 0重量％至約7 0重 量％。雖然第一個聚烯烴溶液內之第一個聚烯烴組成物的 量未有嚴格設限，但是當該量小於約1重量％時，將更難 以在可接受的充分速率下製造出多層微多孔聚烯烴膜。此 外，當該量小於1重量％時，將更難以在擠壓期間預防模 具出口處的膨脹或變狹窄，而難以形成且支撐該多層凝膠 狀片狀物（其乃製造過程期間所形成之膜的前驅物）。另 一方面，當第一個聚烯烴溶液內之第一個聚烯烴組成物的 量大於7 5重量％時，將更難以形成多層凝膠狀片狀物。第 —個聚乙烯樹脂之量宜爲1-50質量％，更佳爲20-40質量 % (相對於每1 〇〇質量％之第一個聚烯烴溶液）。當該聚 乙烯樹脂係少於1質量％，在將第一個烯烴溶液擠壓形成 凝膠狀成型物期間，在模具出口會發生膨脹或變狹窄的現 象，造成該凝膠狀成型物的成型性及自撐性降低。另一方 面，當該聚乙烯樹脂係少於50質量％時，該凝膠狀成型物 的成型性會惡化。 (2 )第二個聚烯烴溶液的製備 第二個聚烯烴溶液可藉由與製備第一個聚烯烴溶液所 用者相同的方法來製備。例如，第二個聚烯烴溶液可藉由 令第二個聚烯烴組成物與第二個膜形成溶劑熔融摻合而製 -27- 200920595 備得。第二個膜形成溶劑可選自與第一個膜形成溶劑柑同 的溶劑。雖然第二個膜形成溶劑可（且通常係）獨立選自 第一個膜形成溶劑’但是，第二個膜形成溶劑可與第一個 膜形成溶劑相同，且可以與第一個膜形成溶劑用於第一個 聚嫌烴溶液者相同的相對濃度來使用。 第二個聚烯烴組成物通常係獨立選自第一個聚烯烴組 成物。第二個聚烯烴組成物包含第二個聚乙烯樹脂及第二 個聚丙烯樹脂。 於一體系中’製備第二個聚烯烴溶液的方法與製備第 一個聚烯烴溶液之方法的不同點在於其混合溫度宜在第二 個聚丙烯之溶點（Tm2)至Tm2 + 90°C的範圍內，且聚烯烴 組成物的量宜爲1至50質量％ ’更佳爲20-40質量％。 (3 )擠壓 於一體系中，第一個聚烯烴溶液係由第一個擠壓機引 導至第一個模具，而第二個聚烯烴溶液則係由第二個擠壓 機引導至第二個模具。由第一個及第二個模具，可擠壓出 分層之呈片狀的擠出物（亦即，平面方向明顯較厚度方向 大的物體）。選擇性地，第一個及第二個聚烯烴溶液可自 第一個及第二個模具共擠出，使得由第一個聚烯烴溶液所 形成之第一個擠出物層的平面表面與由第二個聚烯烴溶液 所形成的第二個擠出物層的平面表面接觸。擠出物之平面 表面可由擠出物之機械方向上的第一個向量以及擠出物之 橫斷方向上的第二個向量來界定。 -28- 200920595 於一體系中，可使用模組’其中模組（die assembly )包含第一個模具及第二個模具，如同，例如，當第—個 模具及第二個模具共有在模組內之含有第一個聚烯烴溶液 的區域及模組內含有第二個聚烯烴溶液的第二個區域之間 的相同隔間。 於另一體系中，可使用多個模具，各模具係連接至擠 壓機以引導第一個或第二個聚烯烴溶液至模具。例如，於 一體系中，含有第一個聚燏烴溶液的第一個擠壓機係連接 至第一個模具及第三個模具’而含有第二個聚嫌烴溶液的 擠壓機則係連接至第二個模具。如在前述體系的情況下， 所得到之分層的擠出物可自第一個、第二個、及第三個模 具共擠出（例如，同時），以形成三層擠出物，其含有由 第一個聚烯烴溶液所形成之構成表面層的第一及第三層（ 例如，頂及底層），以及構成該擠出物之中間層且位於該 二表面層之間並與彼等呈平面接觸的第二層，其中該第二 層係由第二個聚烯烴溶液所形成。 於又另一體系中，係使用相同的模組，但是聚烯烴溶 液係相反的，亦即，含有第二個聚烯烴溶液之第二個擠壓 機係連接至第一個模具及第三個模具，而含有第一個聚烯 烴溶液之第一個擠壓機係連接至第二個模具。 於前述任何體系中，可採用習用的模具擠壓設備，來 進行模具擠壓。例如，擠壓可藉由平模或充氣模（ inflation die)來進行。於可用於共擠壓多層凝膠狀片狀 物的體系中，可採用多口擠壓法（multi-manifold -29- 200920595 extrusion )，其中，第一個及第二個聚稀烴溶液係引導至 多層擠壓模具之各別歧管且在模唇出口上層化。於另一如 是的體系中，可採用塊式擠壓法，其中第一個及第二個聚 烯烴溶液係先倂合爲層流（亦即，事先進行），然後，該 層流可連接至模具。因爲對於習於聚烯烴膜加工技藝之士 而言，多口擠壓法及塊式擠壓法係已知的（例如，如 JP06-122142 A、JP06-106599 A所揭示者），所以彼等方 法被視爲習知者，而不再詳述彼等的操作方法。 ¥寸於模具的選擇並未有嚴格設限，而且例如，可採用 習用之形成多層片狀物的平模或充氣模。模具間隙未有嚴 格限制。例如，形成多層片狀物的平模可具有約〇 · 1 m m 至約5 mm的模具間隙。模具溫度及擠壓速度亦非嚴格設 限的參數。例如，在擠壓期間，模具可加熱至約1 4 0 °C至 約250 °C範圍的模具溫度。擠壓速度可在，例如，約0.2 m /分鐘至約15 m /分鐘的範圍內。分層的擠出物之層厚 度可獨立來選擇。例如，凝膠狀層狀物可具有相對較厚的 表面層（或”皮’’層）（與分層之擠出物的中間層厚度相較 之下）。 雖然擠壓法已藉由產生二及三層擠出物的體系，加以 說明，但是擠壓步驟並不受限於彼等體系。例如，可採用 多個模具及/或模組，使用前述體系所記載的方法，來製 造具有四或更多層的多層擠出物。於如是的分層擠出物中 ，各表面或中間層可使用第一個聚烯烴溶液及/或第二個 聚烯烴溶液來製造。 -30- 200920595 (4)多層凝膠狀片狀物的形成 多層擠出物可藉由，例如，冷卻，而形成多層凝膨狀 片狀物。冷卻速度及冷卻溫度並未有特別嚴格設限。例如 ，多層凝膠狀片狀物可在至少約50 °C /分鐘的冷卻速度下 ，冷卻至多層凝膠狀片狀物的溫度（冷卻溫度）大約等於 多層凝膠狀片狀物之凝膠化溫度（或更低的溫度）爲止。 於一體系中，擠出物係冷卻至約2 5 °C或更低的溫度，以便 形成多層凝膠狀片狀物。雖然不願受縛於任何理論或模式 ，但是吾人相信，分層擠出物的冷卻決定了藉由一或數個 膜形成溶劑來分離之第一個及第二個聚烯烴溶液的聚烯烴 微相。吾人觀察到，一般而言，較慢的冷卻速度（例如， 小於50 °C /分鐘）可提供具有較大準晶胞單位（pseudocell unit ) 之多層 凝膠狀 片狀物 ，而 造成較 粗糙的 高階結 構（higher-order structure)。另一方面，相對較快的冷 卻速度（例如，8 0 °C /分鐘）則會造成較稠密的晶胞單位 。雖然非爲具決定性的參數，但是當擠出物的冷卻速度小 於5 0 °C /分鐘時，可造成層內的聚烯烴結晶度增加，而使 得在後續的拉伸步驟中之多層凝膠狀片狀物的加工難以進 行。冷卻方法的選擇並未有嚴格設限。例如，可採用習用 的片狀物冷卻方法。於一體系中’該冷卻方法包含令分層 的擠出物與冷卻介質（諸如’冷卻空氣、冷卻水等等）接 觸。另外。也可選擇藉令擠出物與經冷卻介質等等冷卻之 滾輪接觸’而予以冷卻。 -31 - 200920595 (5 )第一個及第二個膜形成溶劑的去除 於一體系中’自多層凝膠狀片狀物移除（或取代）至 少一部分的第一個及第二個膜形成溶劑，以便形成溶劑已 去除的凝膠狀片狀物。可使用取代（或”清洗”溶劑）來移 除（洗掉、或取代）第一個及第二個膜形成溶劑。雖然不 願受縛於任何理論及模式，但是吾人相信，因爲由第一個 聚烯烴溶液及第二個聚烯烴溶液所產生之多層凝膠狀片狀 物內的聚烯烴相係與膜形成溶劑相分開的，所以，膜形成 溶劑的去除提供了一多孔膜，該膜係由形成微細立體網狀 結構且具有立體且不規則相通之孔的原纖維所構成。清洗 溶劑的選擇並未有嚴格設限，只要其能夠溶解或取代至少 一部分之第一個及/或第二個膜形成溶劑即可。適當的清 洗溶劑包括’例如，一或多種揮發性溶劑，諸如，飽和的 烴類，諸如’戊烷、己烷、庚烷等等；氯化的烴類，諸如 ’二氯甲烷 '四氯化碳等等；醚類，諸如，乙醚、二噁烷 等等；酮類’諸如，甲基乙基酮等等；線性的氟碳化物， 諸如，三氟乙烷、C6F14、C7F16等等；環狀氫氟碳化物， 諸如’ C5H3F7等等；氫氟醚化物，諸如，C4F9〇CH3、 C4F9〇C2H5等等；以及全氟醚化物，諸如，C4F9〇CF3、 c4f9oc2f5 等等。 去除膜形成溶劑的方法並未有嚴格限制，且可採用任 何能夠去除顯著量之溶劑的方法，包括習用的溶劑去除方 法。例如’可藉由將多層凝膠狀片狀物浸泡於清洗溶劑及 -32- 200920595 /或用清洗溶劑予以沖洗，來清洗該多層凝膠狀片狀物。 所使用之清洗溶劑的量並未有嚴格設限，且通常係取決於 選擇用來去除膜形成溶劑之方法。例如’所使用之清洗溶 劑的量可在約3 00至約30,〇0〇質量份範圍內（基於凝膠 狀片狀物的質量）。雖然對於膜形成溶劑之量並未有特別 嚴格設限，但是，當至少有大量之第一個及第二個膜形成 溶劑自凝膠狀片狀物移除時，通常將可造成較高品質（較 多孔的）膜產生。於一體系中，係自凝膠狀片狀物移除膜 形成溶劑（例如，藉由清洗），直至多層凝膠狀片狀內之 剩餘膜形成溶劑的量變爲小於1重量％ (基於凝膠狀片狀 之重量）爲止。 (6)已去除溶劑之凝膠狀片狀物的乾燥 於一體系中，將藉由去除至少一部分膜形成溶劑所得 到之已去除溶劑的多層凝膠狀片狀物進行乾燥，以去除清 洗溶劑。可採用任何能夠去除清洗溶劑的方法，包括習用 的方法，諸如，加熱乾燥法、風乾法（移動空氣）等等。 在乾燥期間之凝膠狀片狀物的溫度（亦即，乾燥溫度）並 未有嚴格設限。例如，乾燥溫度可等於或低於晶體分散溫 度Ted。Ted係第一個聚乙烯樹脂之晶體分散溫度Tcdi及 第二個聚乙烯樹脂（若有採用時）之晶體分散溫度Tcd2 中的較低者。例如’乾燥溫度可較晶體分散溫度Ted至少 低5 °C。第一個及第二個聚乙烯樹脂之晶體分散溫度可藉 由根據ASTM D 4065來測量聚乙烯樹脂之動力黏彈性的 -33- 200920595 溫度特性，而決定。於一體系中’第—個或第二個 樹脂中至少有一者具有在約90°C至約l〇〇°C範圍內 分散溫度。 雖然未有嚴格設限’乾燥可進行至剩餘清洗溶 係約5重量％或更少爲止（乾燥爲基準’亦即，基 多層微多孔聚烯烴膜的重量）。於另一體系中，乾 行至剩餘清洗溶劑的量爲約3重量％或更少爲止（ 基準）。不充分的乾燥係可辨識出的，因爲其通常 多層微多孔膜之多孔性不合需要地增加。若觀察到 ，應提高乾燥溫度及/或增加乾燥時間。藉由’例 燥或其他的方法來去除清洗溶劑，可導致產生多層 聚烯烴膜。 (7 )拉伸 在去除膜形成溶劑的步驟之前（亦即步驟5之 可拉伸該多層凝膠狀片狀物，以獲得拉伸的多層凝 狀物。吾人相信，多層凝膠狀片狀物內之第一個及 膜形成溶劑的存在，可導致產生相對均勻的拉伸倍 多層凝膠狀片狀物加熱，尤其在拉伸開始時或是在 相對早期階段（例如，在5 0 %的拉伸完成之前）， 有助於拉伸的均句性。 不論是拉伸方法的選擇或是拉伸倍率的程度’ 特別嚴格的設限。例如，任何能夠將多層凝膠狀片 伸至預定倍率的方法（包括任何選擇性的加熱）’ 聚乙烯 的晶體 劑的量 於乾燥 燥係進 乾燥爲 會導致 此現象 如，乾 微多孔 前）， 膠狀片 第二個 率。將 拉伸的 被認爲 皆未有 狀物拉 皆可使 -34- 200920595 用。於一體系中，可藉由下列一或多者來完成：拉幅機式 拉伸（tenter-stretching)、滾輪式拉伸（r〇ller-stretching )、或充氣式拉伸（inflation stretching )(例如，使用 空氣）。雖然在選擇上並未有嚴格設限’拉伸可以單軸（ 亦即，在機器或橫斷方向上）或雙軸（在機器及橫斷二方 向上）進行。於一體系中，可採用雙軸拉伸。在雙軸拉伸 的情況下（亦稱作爲雙軸取向），拉伸可爲同時的雙軸拉 伸，先沿著一個平面軸然後再沿著另一軸的連續拉伸（亦 即首先在橫斷方向然後在機器方向）、或多階段的拉伸（ 例如，同時雙軸拉伸及連續拉伸的組合）。於一體系中， 係採用同時雙軸拉伸。 拉伸倍率並未有嚴格設限。於採用單軸拉伸的體系中 ，線性拉伸倍率可爲，例如，約2倍或更多倍，或是約3 至約3 0倍。於採用雙軸拉伸的體系中，線性拉伸倍率可 爲，例如，約3倍或更多倍（在平面方向）。於另一體系 中，由拉伸所產生之面積倍率係至少約9倍，或至少約1 6 倍，或是至少約25倍。雖然並非具決定性的參數，當拉 伸導致產生至少約9倍之面積倍率時，多層微多孔聚烯烴 膜將具有相對較高的接腳耐壓強度。當達到大於約400倍 的面積倍率時，將更難以操作拉伸裝置。 多層凝膠狀片狀物在拉伸期間的溫度（亦即拉伸溫度 )未有嚴格設限。於一體系中，該凝膠狀片狀物在拉伸期 間的溫度可爲約（Tm+ 1 (TC )或更低，或是選擇性地在高 於Ted但低於Tm的範圍內，其中Tm係第一個聚乙烯之 -35- 200920595 熔點Tmi與第二個聚乙烯（若有使用）之熔點Tm2中的較 小者。雖然此參數並未有嚴格設限，但是當拉伸溫度高於 大約熔點Tm + 10°c時，第一個或第二個聚乙烯中至少有一 者係呈熔融狀態，這會使得在拉伸期間多層凝膠狀片狀物 內之聚烯烴分子鏈的定方向更加困難。且當拉伸溫度低於 大約Ted時，第一個或第二個聚乙烯中至少有一者的軟化 會不夠充分，而難以在不斷裂或撕裂的情況下來拉伸多層 凝膠狀片狀物，這會導致無法達到所要的拉伸倍率。於一 體系中，拉伸溫度係在約9 0 °C至約1 4 0 °C的範圍內，或是 約1 0 0 °c至約1 3 0 °c的範圍內。 雖不願受縛於任何理論或模式，吾人相信，如是之拉 伸會造成聚乙烯薄層之間的剝離，使得聚乙烯相更加纖細 且形成大量的原纖維。彼等原纖維會形成立體的網狀結構 (立體不規則連結的網狀結構）。因此，拉伸（若有採用 )通常會使得相對高機械強度且具有相對大孔徑之多層微 多孔聚烯烴膜更易於製造出。如是多層微多孔膜被認爲特 別適用於作爲電池隔板。 選擇性地，拉伸可在厚度方向（亦即，與多層微多孔 聚烯烴膜之平面表面大約垂直的方向）上，於溫度梯度下 存在下進行。在此情況下，易於製造出具有改良機械強度 之多層微多孔聚烯烴膜。此方法之細節記述於日本專利第 3347854 號 ° (8 )熱溶劑處理步驟 -36- 200920595 雖然並非必須的，但是在步驟（4)及（5)之間，可 用熱溶劑處理多層凝膠狀片狀物。在使用時’吾人相信， 該熱溶劑處理可爲原纖維（諸如’藉由拉伸多層凝膠狀片 狀物所形成者）提供相對厚的葉脈狀結構。此一結構咸信 使得製得具有大孔洞而相對地高強度和高穿透性的多層微 孔膜，成爲比較不困難。「葉脈狀」一詞係指原纖維具有 厚的主幹且由其延伸出呈網狀結構的薄纖維。此方法的細 節記述於 WO 2000/2 0493。 (9 )多層微多孔膜的拉伸（”乾拉伸"） 於一體系中，步驟（6)之乾燥多層微多孔膜可至少 以單軸拉伸。對於選擇的拉伸方法並未有嚴格設限’且可 採用習用的拉伸方法’諸如’藉由拉幅機式拉伸等等。雖 然未有嚴格設限，在拉伸過程中’可將膜加熱。雖然對於 選擇未有嚴格限制’但是拉伸可爲單軸或雙軸的。當採用 雙軸拉伸時，拉伸可在二個軸方向同時進行’或是亦可選 擇以連續方式來拉伸多層微多孔聚烯烴膜’例如’先在機 器方向，然後在橫斷方向進行。於一體系中’係採用同時 雙軸拉伸。當多層凝膠狀片狀已如步驟（7 )所述地進行 拉伸時，步驟（9 )之乾燥多層微多孔聚烯烴膜的拉伸係 稱作爲乾燥拉伸、再拉伸或是乾燥取向（dry_orientation )° 乾燥多層微多孔膜在拉伸期間的溫度（"乾燥拉伸溫 度”）並未有嚴格限制。於一體系中’乾燥拉伸溫度係大 -37- 200920595 約等於熔點Tm或更低，例如，在約晶體分散溫度Ted至 約熔點Tm範圍內。當乾燥拉伸溫度高於Tm時，將更難 以製造出具有相對高的耐壓性且具有相對均勻的空氣滲透 性特性，尤其係在橫斷方向（當乾燥多層微多孔聚烯烴膜 係橫向拉伸時）。當拉伸溫度係低於T c d時，將更難以充 分地軟化第一個及第二個聚烯烴，而在拉伸期間導致撕裂 ，且缺乏均勻拉伸。於一體系中，乾燥拉伸溫度可在約9 0 °C至約1 3 5 °C範圍內，或是約9 5 °C至約1 3 0 °C範圍內。 當採用乾燥拉伸時，拉伸倍率並未有嚴格設限。例如 ，多層微多孔膜的拉伸倍率於至少一個平面（例如，側面 )方向上，可在約1.1倍至約1.8倍範圍內。因此，在單 軸拉伸的情況下，於縱向上（亦即，「機械方向」或橫斷 方向上（取決於該膜係縱向或橫向拉伸）的拉伸倍率可在 約1 .1倍至約1 . 8倍範圍內。單軸拉伸亦可沿著縱向及橫 向之間的平面軸來完成。 於一體系中，係採用沿著二拉伸軸（例如，同時沿著 縱向及橫向）之拉伸倍率爲約1.1倍至約1 · 8倍的雙軸拉 伸。在縱向上的拉伸倍率無需與橫向上的拉伸倍率相同。 換言之，在雙軸拉伸的情況下，拉伸倍率可獨立選擇。於 一體系中，在二個拉伸方向上的乾燥拉伸倍率係相同的。 (1 〇 )熱處理 於一體系中，乾燥的多層微多孔膜可依照步驟（6 ) 進行熱處理。吾人相信，熱處理可安定乾燥多層微多孔聚 -38- 200920595 烯烴膜內的聚烯烴晶體’而形成均句的薄層。於一體中’ 該熱處理係包含熱定型及/或退火。當採用熱定型時，其 可使用習用的方法’諸如’拉幅機式方法及/或滾輪式方 法，來進行。雖然未有嚴格限制，但是在熱定型期間，乾 燥多層微多孔聚烯烴膜的溫度（亦即，「熱定型溫度」） 可在Ted至約Tm範圍內。於一體系中，熱定型溫度可在 約多層微多孔聚烯烴膜之乾燥拉伸溫度±5 t範圍內，或是 約多層微多孔聚烯烴膜之乾燥拉伸溫度±3 t範圍內。退火 與熱定型的不同在於其乃一未施加負荷於多層微多孔聚烯 烴膜的熱處理。對於退火方法的選擇並未有嚴格限制，且 其可藉由採用，例如，裝備有帶式傳送機的加熱室或氣浮 式加熱室，來進行。另外，退火亦可在熱定型之後（拉幅 機布鋏（tenter clips )鬆驰），來進行。在退火期間，多 層微多孔聚烯烴膜的溫度（亦即，退火溫度）係未有嚴格 設限的。於一體系中，退火溫度可在約熔點Tm或更低範 圍內’或是在約6(TC至（Tm-lOt )範圍內。吾人相信， 退火將使得具有相對高滲透性及強度之多層微多孔聚烯烴 膜的製造較不困難。 (1 1 )交聯 於一體系中，在步驟（6)之後，多層微多孔聚烯烴 膜可進行交聯（例如，藉由游離輻射射線，諸如，α射線 、/3射線、r射線、電子光束等等）。例如，當使用輻射 電子光束來交聯時，電子光束輻射的量可在約0. 1 Mr ad至 -39- 200920595 約1 00 Mrad ’所採用之加速電壓係在約100 kV至約300 kV範圍內。吾人相信，交聯處理將使得具有相對較高熔 化溫度之多層微多孔聚烯烴膜的製造較不困難。 (1 2 )親水性處理 於一體系中，多層微多孔聚烯烴膜可進行親水性處理 (亦即，使得多層微多孔聚烯烴膜更加親水性的處理）。 該親水性處理可爲，例如，單體接枝處理、界面活性劑處 理、電暈處理等等。於一體系中，係於交聯處理後，採用 單體接枝處理。 當採用界面活性劑時，任何非離子性界面活性劑、陽 離子界面活性劑、陰離子界面活性劑以及兩性離子界面活 性劑皆可使用，例如，單獨使用或合倂使用。於一體系中 ’係使用非離子界面活性劑。對界面活性劑的選擇並沒有 嚴格限制。例如，可將多層微多孔聚烯烴膜浸入界面活性 劑與水或低級醇（諸如，甲醇、乙醇、異丙醇等等）的溶 液中’或是，例如，藉由流延法，塗覆上該溶液。 B.第二個製造方法 供製造多層微多孔聚烯烴膜的第二個方法包含下列步 驟·· ( 1 )將第一個聚烯烴組成物與第一個膜形成溶劑倂 合（例如，藉由熔融摻合法），以製備第一個聚烯烴溶液 ’ （2 )將第二個聚烯烴組成物與第二個膜形成溶劑倂合 ’以製備第二個聚烯烴溶液，（3 )令第一個聚烯烴溶液 -40- 200920595 擠壓通過第一個模具且令第二個溶液擠壓通過第一 ，然後對經過擠壓的第一個及第二個聚燃烴溶液進 ，而得到多層的擠出物，（4 )將該多層擠出物冷 形成多層凝膠狀片狀物’ （5)自該多層凝膠狀片 除至少部分的膜形成溶劑，而形成已去除溶劑的凝 狀物，以及（6 )將該已去除溶劑的凝膠狀片狀物 以便形成多層微多孔膜。視需要’在步驟（4 )及 間可進行任選的拉伸步驟（7 )以及任選的熱溶劑 驟（8 )等等。在步驟（6 )之後’可進行拉伸該多 孔膜的任選步驟（9 )、任選熱處理步驟（1 〇 )、 輻射進行交聯的任選步驟（1 1 )、以及任選的親水 步驟（1 2 )等等。 第二個製造方法之過程步驟及條件通常係與有 個製造步驟的部分所敘述的類似步驟者相同，除了 3 )之外。因此，將對步驟（3 )詳加說明。 對於所使用之模具並未有嚴格限制，只要該模 形成可層合之擠出物即可。於一體系中，係採用片 具（彼等係相鄰或連接在一起），來形成擠出物。 及第二個片狀物模具係分別連接於第一個及第二個 ，其中第一個擠壓機含有第一個聚烯烴溶液，而第 壓機含有第二個聚烯烴溶液。雖然未有嚴格限制， 擠壓的第一個及第二個聚烯烴溶液仍然在大約擠壓 時，通常較易於進行層合。其他的條件則可與第一 中的相同。 個模具 行層合 卻，而 狀物去 膠狀片 乾燥， (5 )之 處理步 層微多 以游離 性處理 關第一 步驟（ 具能夠 狀物模 第一個 擠壓機 二個擠 但是當 溫度下 個方法 -41 - 200920595 於另一體系中，第一個、第二個及第二個片狀物模具 係連接至第一個、第二個及第三個擠壓機’其中第一個及 第三個片狀物模具係含有第一個聚烯烴溶液’而第二個片 狀物模具則係含有第二個聚烯烴溶液。於此體系中’所形 成之層合擠出物係由包含擠壓的第一個聚嫌煙溶液之外層 以及包含擠壓的第二個聚烯烴溶液的中間層所構成° 於又另一體系中，第一個、第二個、以及第三個片狀 物模具係連接至第一個、第二個及第三個濟壓機’其中第 二個片狀物模具係含有第一個聚烯烴溶液’而第一個及第 三個片狀物模具則係含有第二個聚烯烴溶液。於此體系中 ，所形成之分層的擠出物係由包含擠壓的第二個聚烯烴溶 液之外層以及包含擠壓的第一個聚烯烴溶液的中間層所構 成。 C.第三個製造方法 供製造多層微多孔聚烯烴膜的第三個方法包含下列步 驟：（1 )將第一個聚烯烴組成物及膜形成溶劑倂合（例 如，藉由熔融摻合法），以製備第一個聚烯烴溶液，（2 )將第二個聚烯烴組成物及第二個膜形成溶液倂合，以製 備第二個聚烯烴溶液，（3)令第一個聚烯烴溶液擠壓通 過至少一個第一個模具’而形成至少一個第一個濟出物， (4)令第二個聚烯烴溶液擠壓通過至少一個第二個模具 ’而形成至少一個第二個擠出物，（5)將第一個及第二 個擠出物冷卻’而形成至少一個第一個凝膠狀片狀物以及 -42- 200920595 至少一個第二個凝膠狀片狀物，（6)對第一個及第二個 凝膠狀片狀物進行層合，而形成多層的凝膠狀片狀( 7 )自結果所得到的多層凝膠狀片狀物移除至少部分@目莫 形成溶劑，已形成以去除溶劑的凝膠狀片狀物’以& ( 8 )將該已去除溶劑的凝膠狀片狀物乾燥，而形成多層@ # 孔膜。視需要，在步驟（5 )及（6 )之間，或是步驟（6 )與（7 )之間，可進行任選的拉伸步驟（9 )、以及任選 的熱溶劑處理步驟（1 0 )等等。在步驟（8 )之後’可進 行拉伸多層微多孔膜的任選步驟（11)、任選的熱處理步 驟（1 2 )、以及以游離輻射進行之任選的交聯步驟（1 3 ) 、以及任選的親水性處理步驟（14)等等。 第三個製造方法與第二個製造方法之主要差異在於層 合及冷卻步驟的順序。 在第二個製造方法中，係於冷卻步驟之前，進行第一 個及第二個聚烯烴溶液的層合。於第三個製造方法中’第 一個及第二個聚烯烴溶液係於層合步驟之前冷卻。 在第三個製造方法中的步驟（1) 、 （2) 、 （7)及 (8)可與前述之第一個製造方法中的步驟（1) 、 （2) 、（5)及（6)相同。就令第一個聚烯烴溶液通過第一個 模具進行的擠壓而言’第二個製造方法之步驟（3)的條 件用於第三個製造方法之步驟（3)。就令第二個聚烯烴 溶液通過第二個模具進行擠壓而言’第三個製造方法之步 驟（4 )的條件可與第二個製造方法之步驟（3 )的條件相 同。於一體系中’不論係第一個或第二個聚烯烴溶液皆係 -43- 200920595 擠壓通過第三個模具。依此方式，所形成之多層的層合物 可具有由第一個聚烯烴溶液所產生的二層以及由第二個聚 烯烴溶液所產生的單層，或是反之。 第三個製造方法的步驟（5)可與第一個製造方法之 步驟（4)相同’除了在第二個製造方法中，第一個及第 二個凝膠狀片狀物係分別形成之外。 對第一個及第二個凝膠狀片狀物進行層合的步驟（6 )將詳述於下文。對於層合之方法並沒有嚴格設限，且可 使用習用的層合方法，諸如，熱誘發層合法（Ιιεαί-ί n d u c e d 1 a m i n a t i ο n m e t h 〇 d s ) ， 來層 合該多 層凝媵 狀片狀 物。其他適當的層合方法包括，例如，熱封法、瞬熱式封 法（impulse-sealing )、超音波壓接法（ultrasonic-bo n d i n g ) 等等 ，彼等 可單獨 或合倂 使用。 熱封法 可採用 ，例如，一或更多對的已加熱滾輪來進行，其中該凝膠狀 的片狀係被引導通過至少一對已加熱的滾輪。雖然對於熱 封溫度及壓力並沒有嚴格限制，但是應施予充分時間之充 分加熱及壓力，以確保凝膠狀片狀物適當地接合，以提供 具有相對均勻性質且脫層傾向小的多層微多孔膜。於一體 系中，熱封溫度可爲，例如，約9 0 °C至約1 3 5 °C，或是約 9 0 °C至約1 1 5 °C。於一體系中，熱封壓力可爲約〇 . 〇 1 MP a 至約-5 0 Μ P a。 如在第一個及第二個製造方法的情況下，由第一個及 第二個聚烯烴溶液所形成之層（亦即’包含第一個及第二 個微多孔層物質的層）的厚度’可藉由調節第一個及第二 -44- 200920595 個凝膠狀片狀物的厚度以及藉由拉伸的量（拉伸倍率及乾 燥拉伸倍率）（當使用了一或多個拉伸步驟時），加以控 制。選擇性地，可藉令凝膠狀片狀物通過多階段的加熱滾 輪，將層合步驟及拉伸步驟倂合。 於一體系中，第三個製造方法形成了具有至少三層的 多層聚烯烴凝膠狀片狀物。例如，在將二個擠壓的第一個 聚烯烴溶液及一個擠壓的第二個聚烯烴溶液冷卻而形成凝 膠狀片狀物之後，多層凝膠狀片狀物可與包含了擠壓的第 一個聚烯烴溶液的外層以及包含擠壓的第二個聚烯烴溶液 的中間層層合。於另一體系中，在將二個擠壓的第二個聚 烯烴溶液及一個擠壓的第一個聚烯烴溶液冷卻而形成凝膠 狀片狀物之後’多層凝膠狀片狀物可與包含了擠壓的第二 個聚烯烴溶液的外層以及包含擠壓的第一個聚烯烴溶液的 中間層層合。 拉伸步驟（9 )及熱溶劑處理步驟（1 〇 )可與第一個 製備方法所記述之拉伸步驟（7 )及熱溶劑處理步驟（8 ) 相同，但是拉伸步驟（9 )及熱溶劑處理步驟（丨〇 )可在 第一個及/或第二個凝膠狀片狀物上進行。對於第一個及 第二個凝膠狀片狀物的拉伸溫度並未有嚴格設限。例如， 第一個凝膠狀片狀物的拉伸溫度可爲，例如，Tm ! + 1 0 〇C或 更低’或是選擇性地爲約Ted!或更高但是低於Tmi。第二 個凝膠狀片狀物的拉伸溫度可爲，例如，T m 2 + 1 0。(：或更低 ，或是選擇性地爲約Tcd2或更高但低於約Tm2。 -45- 200920595 D.第四個製造方法 供製造多層微多孔聚烯烴膜的第四個方法包含 驟：（1 )將第一個聚烯烴組成物與膜形成溶劑倂 如，藉由熔融摻合法）’以製備第一個聚稀烴溶货 將第二個聚烯烴組成物與第二個膜形成溶劑倂合， 第二個聚烯烴溶液，（3)令第一個聚烯烴溶液擠 至少一個第一個模具，而形成至少一個第一個擠出 4)令第二個聚烯烴溶液擠壓通過至少一個第二個 而形成至少一個第二個擠出物，（5)將第一個及 擠出物冷卻，形成至少一個第一個凝膠狀片狀物及 個第二個凝膠狀片狀物，（6)自第一個及第二個 片狀物，去除至少部分的第一個及第二個膜形成溶 成已去除溶劑的第一個及第二個凝膠狀片狀物，！ 已去除溶劑的第一個及第二個凝膠狀片狀物乾燥， 少一個第一個聚烯烴膜以及至少一個第二個聚烯烴 及（8)將第一個及第二個多孔聚烯烴膜層合，以 多層微多孔聚烯烴膜。 視需要，在步驟（5 )及（6 )之間，可進行拉 (9 }、熱溶劑處理步驟（10 )等等。視需要，在当 )及（8 )之間’可進行拉伸步驟（丨丨）.、熱處理 12 )等等。視需要，在步驟（8 )之後，可進行拉 微多孔膜的步驟（13)、熱處理步驟（14)、使用 射的交聯步驟（1 5 )、親水性處理步驟（〗6 )等等 第四個製備方法中的步驟（1)及（2)可在與 下列步 合（例 交（2 ) 以製備 壓通過 物，（ 模具， 第二個 至少一 凝膠狀 劑，形 :7 )將 形成至 膜，以 便形成 伸步驟 ?驟（7 步驟（ 伸多層 游離輻 〇 第一個 -46- 200920595 製造方法中的步驟（1 )及（2 )相同的條件下進行。第四 個製造方法中的步驟（3) 、 （4)及（5)可在與第三個 方法中之步驟（3 ) 、 （ 4 )及（5 )相同的條件下進行。 第四個製造方法中的步驟（6)可在與第一個製造方法之 步驟（5)相同的條件下進行，但是自第一個及第二個凝 膠狀片狀物去除膜形成溶劑的部分除外。第四個製造方法 中的步驟（7)可在與第一個製造方法之步驟（6)相同的 條件下進行，但是在第四個製造方法中，第一個及第二個 已去除溶劑的凝膠狀片狀係分開乾燥的。第四個製造方法 中的步驟（8)可在與第三個製造方法之步驟（6)相同的 條件下進行，但是將第一個及第二個聚烯烴微多孔膜層合 的部分除外。第四個製造方法中的拉伸步驟（9 )及熱溶 劑處理步驟（10)可在與第三個製造方法之步驟（9)及 (1 〇 )相同的條件下進行。第四個製造方法中的拉伸步驟 (11)及熱處理步驟（12)可在與第一個製造方法的步驟 (9 )及（1 0 )相同的條件下進行，但是在第四個製造方 法中，第一個及第二個聚烯烴微多孔膜係經過拉伸及/或 熱處理的。 於一體系中，在第四個製造方法的拉伸步驟（11)中 ，第一個聚烯烴微多孔膜的拉伸溫度可爲約Tm i或更低， 或是選擇性地爲Tcdt至約Tm,，且第二個聚烯烴微多孔膜 的拉伸溫度可爲約Tm2或更低，或是選擇性地爲約Tcd2 至約T m 2。 於一體系中，第四個製造方法中的熱處理步驟（12) -47- 200920595 可爲HS及/或退火。例如，在第四個製造方法之熱處理 步驟（12)中，第一個聚烯烴微多孔膜的熱定型溫度可爲 約Ted!至約Τπμ，或是選擇性地爲約乾燥拉伸溫度±5°C ，或是選擇性地爲約乾燥溫度±3 t。於一體系中，在第四 個製造方法之熱處理步驟（12)中，第二個微多孔膜的熱 定型溫度可爲約Tcd2至約Tm2，或是選擇性地爲乾燥拉伸 溫度±5 °C，或是選擇性地爲乾燥拉伸溫度±3 °C。在採用 HS時，其可藉由，例如，拉幅機式方法（tenter method) 或滚輪式方法（roller method)，來進行。 於一體系中，在第四個製造方法之熱處理步驟（12) 中’第一個微多孔膜的退火溫度可爲約Tmi或更低，或是 選擇性地爲約 6 0 °C至約（Tm ! -1 0 °C )。在一體系中，於 第四個製造方法之熱處理步驟（12)中，第二個微多孔膜 的退火溫度可爲約T m 2或更低，或是選擇性地爲約6 0 °C 至約（T m 2 -1 0 °C )。 第四個製造方法中之拉伸多層微多孔膜步驟（13)、 熱處理步驟（1 4 )、使用游離輻射的交聯步驟（1 5 )、以 及親水性處理步驟（1 6 )的條件與第一個製造方法之步驟 (9) 、 （1〇) 、 （11)及（12)者相同。 [4]多層微多孔聚烯烴膜的性質 在一體系中，多層微多孔聚烯烴膜的厚度係在約3 μηι 至約200μιη範圍內，或是約5μιη至約50μιη範圍內。選擇 性地’該多層微多孔聚烯烴膜具有一或多個下列特性。 -48- 200920595 A _孔隙率爲約2 5 %至約8 0 % 當孔隙率小於2 5 %時，多層微多孔聚烯烴膜通常不會 呈現出用作爲電池隔板之所要的透氣性。當孔隙率超過 8 0 °/。時’更加難以製造出具有所需要之強度的電池隔板， 這會增加內部電極短電路的的可能性。 Β 1 .透氣性爲約2 0秒/ 1 0 0 c m3至約7 0 0秒/ 1 0 0 c m3 (轉化至在2 0 - μ m厚度的値） 當多層微多孔聚烯烴膜的透氣性（如根據J I S P 8 1 1 7 所測得者）在約20秒/ 100 em3至約700秒/ 100 cm3範 圍內時’則較不難形成具有所要之充電儲存容量及所要之 充放電循環性的電池。當透氣性小於約2 0秒/ 1 0 0 c m3 時，則較難以製造出具有所要之關閉特性的電池，尤其在 電池內的溫度升高時。根據JIS P8117，在具有厚度ΤΊ之 多層微多孔膜上所測得之透氣性P !可藉由方程式P2= ( P , x20 ) / T!，轉換爲厚度20μιη的透氣性P2。 B2.熱壓縮後之透氣性爲約100秒/ 100 cm3至約 1000 秒 /100cm3 當在2.2MP a的壓力下熱壓縮5分鐘時，本發明之多 層微多孔膜具有之透氣性（根據JIS P8117測得的）係約 1 000秒/ 100 cm3或更小，諸如，約100至約1 000秒/ 100 cm3。採用如是膜的電池具有適當大的電容量及充放 -49- 200920595 電循環性。在熱壓縮後之透氣性宜爲，例如，950秒/ 100 cm3或更小。 C.接腳耐壓強度（pin puncture strength)爲約 2,000 mN / 20μιη 或更大 接腳耐壓強度（轉換在20μΐη膜厚度的値）係指在2 mm /秒的速度下，用具有球端表面（spherical end surface)(曲率半徑：0.5 mm)之直徑1 mm的針來刺扎 多層微多孔聚烯烴膜時所測得的最大負荷。當多層微多孔 聚烯烴膜的接腳耐壓強度小於2,000 mN / 20μηι時，將更 難以製造出具有所要之機械完整性、耐久性及韌性的電池 Η.關閉溫度爲約140°C或更低 當多層微多孔聚烯烴膜的關閉溫度超過1 40 °C，則會 更難以製造出在電池過熱時所要之關閉反應的電池隔板。 測定關閉溫度的方式之一涉及在下列條件下’測定在接近 多層微多孔聚烯烴膜之熔點時所觀察到反曲點的溫度··以 5°C /分鐘的速度，將縱向3 mm且橫向10 mm之試驗片 自室溫開始加熱，同時在2§的負荷下’在縱向上延拉該 試驗片。於一體系中，關閉溫度係在約120_140 °C範圍內 。該測量可如下進行。採用熱機械分析儀（τ M A / s s 6 〇 〇 〇 ，購自 Seiko Instruments, Inc.)，以 5°C / 分鐘的速率， 自室溫開始，對多層微多孔膜之10 mm(TD) x3 mm( -50- 200920595 MD )的試驗片，進行加熱，同時以2gf的恆定負荷，在 縱向上拉伸該試驗片’將接近試驗片熔點處所觀察到之試 樣長度反曲點的溫度被定義爲"關閉溫度”（例如，參見第 4圖）。 I ·熔融溫度爲至少約1 7 0 °c 於一體系中’熔融溫度可在約1 7 0 °C至約} 9 0。(：範圍 內。測量熔融溫度的方式之一涉及在下列條件下，測定縱 向3 mm且橫向1 0 mm之多層微多孔聚烯烴膜試驗片因熔 化而斷裂的溫度：以5 °C /分鐘的加熱速率，加熱該試驗 片且同時在2 g負荷下延拉該試驗片。 K. 電池電容量回復率爲70%或更高（鋰二次電池的 抗衰減性質） 當包含多層微多孔膜所形成之隔板的鋰離子二次電池 儲存於80 °C下30天時，所企求之電池電容量回復率[(在 高溫下儲存後的電容量）/ (起始電容量）]xl〇〇(%)應 爲70%或更高。電池電容量回復率宜爲75 %或更高。 L. 在熱壓縮後的厚度變動率爲20%或更小 於90 °C下、2.2 MPa的壓力下熱壓縮5分鐘後的厚度 變動率通常每100%之壓縮前厚度爲20%或更小，較佳宜 小於1 0 %。包含變動率爲2 0 %或更小之膜隔板的電池具有 適當大的容量及良好的充放電循環性。 -51 - 200920595 [5 ]電池隔板 於一體系中，藉由前述多層微多孔聚烯烴膜所形成之 電池隔板所具有的厚度在約3μηι至約200μιη範圍內，或 是約5μηι至約50μιη範圍內。取決於，例如，電解質的選 擇，隔板的潤脹可能會使最終厚度增加至大於200μιη之値 [6]電池 於一體系中，多層微多孔聚烯烴膜可用作爲一次及二 次電池的隔板，諸如，鋰離子電池、鋰-聚合物二次電池 、鎳-氫二次電池、鎳-鎘二次電池、鎳-鋅二次電池、銀-鋅二次電池、且特指鋰離子二次電池。於下文中，將對鋰 離子二次電池進行說明。 鋰二次電池包含陰極、陽極及位於陽極及陰極之間的 隔板。該隔板通常含有電解溶液（電解質）。對於電極的 結構並沒有嚴格限制，且可使用傳統的電極結構。電極結 構可爲’例如，鈕扣型（其中圓盤狀陰極及陽極係對立的 );層疊型（其中平面片狀陰極及陽極係交互與位於陽極 及陰極之間的至少一個隔板層疊在一起）：以及環型的（ 其中帶狀陰極及陽極係纏繞在一起），等等。 該陰極通常係包含集電體、以及能夠吸收且放出鋰離 子的陰極活性物質層（其係形成於集電體之上）。該陰極 活性物質可爲’例如，無機化合物，諸如，過渡金屬氧化 -52- 200920595 物、鋰及過渡金屬的複合氧化物（鋰複合氧化物）、過渡 金屬硫化物等等。該過渡金屬可爲，例如，V、Mn、Fe、 Co、Ni等等。於一體系中，該鋰複合氧化物可爲鎳酸鋰 、鈷酸鋰、錳酸鋰、基於a -NaFe02之層狀鋰複合氧化物 等等。該陽極通常包含集電體、以及形成於該集電體之上 的負電極活性物質層。該負電極活性物質可爲，例如，碳 物質，諸如，天然石墨、人工石墨、焦炭、碳黑等等。 該電解溶液可藉由將鋰鹽溶解於有機溶劑中而得到。 對於溶劑及/或鋰鹽的選擇並沒有嚴格的限制且可採用習 用的溶劑及鹽類。鋰鹽類可爲，例如，LiC104、LiPF6、 LiAsF6、LiSbF6、LiBF4、LiCF3S03、LiN(CF3S02)2、 LiC(CF3S02)3、Li2B10Cl10、LiN(C2F5S02)2、LiPF4(CF3)2 、LiPF3(C2F5)3、鋰的低級脂族羧酸鹽、LiAlCl4等等。鋰 鹽類可單獨或合倂使用。有機溶劑可爲具有相對較高（與 電池的關閉溫度相較之下）之沸點以及高介電常數的有機 溶劑。適當的有機溶劑包括：碳酸乙烯酯' 碳酸丙烯酯、 碳酸乙基甲酯、r -丁內酯等等；具有低沸點及低黏度的 有機溶劑，諸如，四氫呋喃、2 -甲基四氫呋喃、二乙氧基 乙烷、二噁烷、碳酸二甲酯、碳酸二乙酯、以及類似物， 包括彼等之混合物。由於通常具有高介電常數的有機溶劑 常具有高黏度，且反之亦然，所以可使用高及低黏度溶劑 的混合物。 在組合電池時，通常係以電解溶液浸透隔板，而爲該 隔板（多層微多孔膜）提供離子滲透性。對於浸透方法的 -53- 200920595 選擇並未有嚴格限制’且可採用習用的浸透方法。例如， 可藉由將多層微多孔膜浸入在室溫下的電解溶液中，來進 行浸透處理。 對於選擇用來組合電池的方法，並未有嚴格限制，且 可採用習用的電池組合方法。例如，在組合圓筒型電池時 ’係依序層合陰極薄片、由多層微多孔膜所形成的隔板以 及陽極薄片，並且將結果所得到的層合物纏繞爲環形電極 組合。可能需要有第二個隔板來防止環形繞組（windings )的短電路。結果所得到的電極組合可嵌入電池，然後， 用前述電解溶液予以浸透，並且經由墊圈，將裝備有安全 閥之作爲陰極終端的電池蓋塡塞於電池，而製造出一電池 【實施方式】 [7]實施例 參照下文的非限制性實施例，對於本發明進行更詳盡 的說明。 實施例1 (1 )第一個聚烯烴溶液的製備 藉由乾燥摻合法，來製備第一個聚烯烴組成物’其包 含（a) 82% PE1’其具有重量平均分子量3_0xl05以及分 子重量分佈8.6，（b) 8 % PE2，其具有重量平均分子量 2·0χ106及分子重量分佈8， （c) 10%第一個聚丙嫌樹脂 -54- 200920595 ，其具有重量平均分子量1·40χ106、熔化熱iii.6J/g、 分子量爲1·8χ1〇6或更大的部分且該部分係佔25·3%、以 及分子量分佈2 · 6 (百分比係基於第一個聚烯烴組成物的 重量）。該組成物內的聚乙烯樹脂具有熔點135t及晶體 分散溫度l〇〇°C。 將25重量份之結果所得到的聚烯烴組成物裝入強力 摻合的雙輥擠壓機（其內徑爲58 mm且L/D爲42)，並 且經由側面進料機，將75質量份之液態石蠟（在40°C下 爲50 cst)供應至該雙輥擠壓機內。於210°C及200 rpm 下，進行熔融摻合，以製備第一個聚烯烴溶液。 (2 )第二個聚烯烴溶液的製備 依照與前述相同的方式（除了下文所述者之外），來 製備第二個聚烯烴溶液。藉由乾燥摻合法，來製備第二個 聚烯烴組成物，其包含··（ a ) 4 7 % P EI，其具有重量平均 分子量3·0χ105及分子重量分佈8.6，以及（b) 3% PE2, 其具有重量平均分子量2.OxlO6及分子重量分佈8，以及 (c ) 50 %第二個聚丙烯樹脂，其具有重量平均分子量1.40 X106、熔化熱111.6 J/g、具有分子量爲1·8χ106或更大 的部分且該部分係佔25.3%以及分子重量分佈2.6(百分 比係基於第二個聚烯烴組成物之重量）。該組成物內的聚 乙烯樹脂具有熔點135°C且晶體分散溫度爲l〇〇t。將35 重量份之結果所得到的第二個聚烯烴組成物裝入強力摻合 的雙輥擠壓機（內徑58mm且L/D爲42)，並且藉由側 -55- 200920595 面進料機，將65質量份之液態石蠟（在40°C下爲50 )供應至該雙輥擠壓機內。於210°C及200 rpm下，進 熔融摻合，以製備第二個聚烯烴溶液。 (3 )膜的製造 分別由彼等各別的雙輥擠壓機，將第一個及第二個 烯烴溶液供應至三層擠壓T-模具，並且自該模具擠壓形 層厚度爲42.5 / 10/ 42.5之第一個聚烯烴溶液層/第二 聚烯烴溶液層/第一個聚烯烴溶液層的擠出物（亦稱作 層合物）。在令該擠出物通過控制在2 0°C之冷卻滾輪的 時，予以冷卻，而形成三層凝膠狀片狀物，於1 1 8 °C下 藉由拉幅機式拉伸機械，同時在機器（縱向）及橫斷方 上，對其進行同時雙軸拉伸，拉伸至5倍的倍率。將該 過拉伸的三層凝膠狀片狀物固定於20 cmx20 cm的鋁框 ，將其浸入控制在2 5。(：的二氯甲烷浴中，以1 00 rpm的 動（進行3分鐘），去除液態石蠟，並且於室溫下，藉 氣流予以乾燥。藉由批次拉伸機器（batch-stretchi machine)，在i25t下，於橫斷方向上，將該乾燥的膜 拉伸至1.4倍的倍率。於125°C下，將該再拉伸過的膜 其依然固定於批次拉伸機器上）熱固定10分鐘，而製 出三層微多孔膜。 實施例2 重複實施例1，但是不對乾燥的三層膜進行再拉伸< C St 行 聚 成 個 爲 同 ) 向 經 上 振 由 ng 再 ( 造 -56 - 200920595 實施例3 重複實施例1，但是第一個及第二微多孔聚烯烴膜係 依第一個微多孔膜/第二個微多孔膜/第一個微多孔膜的 順序，以25 / 5 0 / 25的層厚度比進行層合的。 實施例4 重複實施例1，但是第一個聚烯烴組成物內的第一個 聚丙烯樹脂係具有6.6xl〇5的重量平均分子量、103.3 J / g 的熔化熱、分子量爲1.8xl06或更大的部分且該部分佔 8.2 %以及1 1的分子量分佈。 實施例5 重複實施例1，但是，第一個聚烯烴組成物內的第一 個聚丙烯樹脂係具有6.8x105的重量平均分子量、94.6 J/ g的熔化熱、分子量爲1 .8x1 06或更大的部分且該部分佔 4 · 7 %、以及5.9的分子量分佈。 實施例6 重複實施例1，但是第一個聚烯烴組成物內的第一個 聚丙稀樹脂係具有3·0χ105的重量平均分子量、88.9 J/g 之熔化熱、分子量爲1·8χ106或更大的部分且該部分佔〇% 、以及4·9的分子量分佈。 -57- 200920595 實施例7 重複實施例1，但是第二個聚烯烴組成物內的第二個 聚丙烯樹脂係具有〇·9〇χ1〇6的重量平均分子量、109.7 J/ g的熔化熱、分子量爲1.8x1 06或更大的部分且該部分佔 1 0 · 8 %、以及2.4的分子量分佈。 實施例8 重複實施例1，但是第二個聚烯烴組成物內的第二個 聚丙烯樹脂係具有2·69χ1〇6的重量平均分子量、99.9 J / g 的熔化熱、分子量爲1·8χ106或更大的部分且該部分佔 5 7.2 %、以及3 · 8的分子量分佈。 實施例9 重複實施例1，但是第一個聚烯烴溶液內的第一個聚 烯烴組成物包含9 0 % P E 1以及1 〇 %第一個聚丙烯樹脂（百 分比係基於第一個聚烯烴組成物的重量）。在此第一個聚 烯烴組成物中，沒有第二個聚乙烯樹脂。 實施例1 〇 重複實施例1，但是第二個聚烯烴溶液內的第二個聚 烯烴組成物包含5 0 % P E 1以及5 0 %第一個聚丙烯樹脂（百 分比係基於第一個聚烯烴組成物的重量）°在此第二個聚 烯烴組成物中，沒有第二個聚乙烯樹脂。 -58- 200920595 比較實施例1 重複實施例1，但是第一個聚烯烴溶 烯烴組成物包含82%第一個聚乙烯樹脂以 乙烯樹脂，未添加第一個聚丙烯樹脂（百 個聚烯烴組成物的重量）。 比較實施例2 重複實施例1，但是第一個聚烯烴溶 烴組成物除外。沒有第一個聚烯烴組成物 比較實施例3 重複比較實施例1，但是第一個聚烯 一個聚丙烯樹脂具有6.8xl05的重量平均夕 g之熔化熱、分子量爲1.8xl06或更大的 4 ·7%、以及5.9的分子量分佈，且第二個 的第二個聚丙烯樹脂係具有6.8χ105的重 94.6 J / g的熔化熱、分子量爲ΐ·8χ106或 部分佔4 _ 7 %、以及5.9的分子量分佈。 比較實施例4 重複實施例1，但是第一個聚烯烴組 聚丙烯樹脂係具有1.56xl06的重量平均分 的熔化熱、分子量爲1.8χ106或更大的ί 3 5 _4%、以及3 2的分子量分佈’且第二 液內的第一個聚 及1 8 %第二個聚 分比係基於第一 液的第一個聚稀 烴組成物內的第 卜子量、94·6 J / 部分且該部分佔 聚烯烴組成物內 量平均分子量、 更大的部分且該 成物內的第一個 子量、78.4 J/ g 分且該部分佔 聚烯烴組成物 -59- 200920595 內的桌一個聚丙稀樹脂係具有1.56χ1〇6的重量平均分子量 、78.4 J / g的熔化熱、分子量爲ι8χ1〇6或更大的部分且 該部分佔35.4°/。、以及3.2的分子量分佈。 比較實施例5 重複比較實施例1，但是第二個聚烯烴溶液內的第二 個聚烯烴組成物除外。沒有第二個聚烯烴組成物。 性質 實施例1 - 6及比較實施例1 - 8的多層微多孔膜的性質 係藉由下列方法測量得的。結果示於表1及2。 (1 )平均厚度（μπι) 藉由接觸式厚度計，於10 cmxlO cm面積的膜上’以 1 0 mm間隔，測量各微多孔膜的厚度，且予以平均。所採 用之厚度計係Mitsutoyo Corporation所製造的Litematic (2) 厚度的標準偏差（μιη) 如前文所述地測量各微多孔膜的厚度。基於厚度的數 據，來計算厚度的標準偏差。 -60- 200920595 各具有厚度1^的微多孔膜所測量得的透氣率Pl$f化 度20μιη的透氣率P2。 (4 )孔隙率（％ ) 藉由重量法，使用下式測量得：孔隙率。/。=100>< ( w2_ wl ) / w2，其中"wl"係薄膜的實際重量，而、2，，係1〇〇% 聚乙烯的假定重量。 (5 )接腳耐壓強度（mN / 20μιη) 當在 2 mm /秒的速度下，用具有球端表面（ spherical end surface)(曲率半徑：0.5 mm)之直徑 1 m m的針來刺扎每一個具有厚度T!的微多孔膜時，測得最 大負荷。藉由方程式L2= ( LlX20 ) / Ti，將測量得的最大 負荷轉化爲厚度20μιη時的最大負荷L2，且用作爲接 腳耐壓強度。 (6 )熱壓縮後的厚度變動率（％ ) 將微多孔膜試樣置於一對高度平坦的薄板之間’並且 藉由沖壓機，於2.2 MPa (22 kgf / cm2)壓力、90°C下’ 進行熱壓縮5分鐘，依與前述相同的方式’測定平均厚度 。藉由方程式：（壓縮後的平均厚度-壓縮前的平均厚 度）/ (壓縮前的平均厚度）χΐ〇〇’來計算厚度變動率’ 其可表示爲絕對値。 -61 - 200920595 (7)熱壓縮後的透氣率（秒/ wocn^) 於前述條件下，對於具有厚度Τι之各多層微多孔膜 進行熱壓縮，並且根據JIS Ρ 8 1 1 7，就透氣率ρ !進行測量 (8 )電解溶液的吸收速度 使用動力表面張力測量裝置（DCAT21，裝備有高精 密度的電子天平，可購自Eiko Instruments Co., Ltd.)， 將多層微多孔膜試樣浸入保持在18 °C的電解溶液（電解質 :1 mol / L LiPF6 ’溶劑：體積比3/7的碳酸乙烯酯/碳 酸二甲酯）中，藉由方程式：[微多孔膜的重量增加（g) /吸收前的微多孔膜重量（g )]，來測定電解溶液吸收速 度。電解溶液吸收速度係以相對値來表示，假定比較實施 例5之微多孔膜的電解溶液吸收速度爲1。 (9 )關閉溫度（t ) 關閉溫度係如下測量得的：由微多孔膜切割出一片3 m m X 5 0 m m的三角形試樣，使得試樣的縱向方向與微多孔 膜的橫斷方向成一線，並且將其固定於熱機械分析儀（ TMA / SS6000，購自 Seiko Instruments, Inc.)，夾頭（ chuck)距離爲10 mm。將19.6 mN的負荷施予該試樣的 較低端，以5 °C /分鐘的速率進行溫度的升高，以測量大 小的變化。在接近熔點處所觀察到之反曲點的溫度被定義 爲關閉溫度。 -62- 200920595 (10)熔融溫度（°C ) 與前述關閉溫度一樣地，使用熱機械分析儀（TMA / SS6〇〇〇’ 購自 Seiko Instruments，Inc.)，來測量熔融溫 度。熔融溫度係膜斷裂時的溫度。 (11 )電容量回復率 如下所述地，對含有多層微多孔膜作爲隔板之鋰離子 電池的電容量回復率進行測量：首先，在高溫儲存之前， 藉由充電/放電試驗機，測量該鋰離子電池的放電量（起 始電容量）。於80 °C下儲存30天後，利用相同的方法， 再次測量放電量，而得到高溫儲存後的電容量。藉由下列 方程式來決定電池的電容量回復率（％ ):電容量回復率 (%)=[(高溫儲存後的電容量）/(起始電容量）]χ100 -63- 200920595 表1 編號 實施例1 實施例2 實施例3 實施例4 實施例5 實施例6 樹脂組成物 第一個聚烯烴 PEI Mw 3.0 x10s 3.0 xlO5 3.0 x10s 3.0 xlO5 3.0 x10s 3.0 xlO5 Mw/Mn 8.6 8.6 8.6 8.6 8.6 8.6 質量％ 82 82 82 82 82 82 PE2 Mw 2.0 xlO6 2.0 xlO6 2.0 χ 106 2.0 χΙΟ6 2.0 χ 106 2.0 χ 106 Mw/Mn 8 8 8 8 8 8 質量％ 8 8 8 8 8 8 PP Mw 1.40 x 106 1.40 χ ΙΟ6 1.40 χ 1〇6 6.6 χΙΟ5 6.8 xlO5 3.0 xlO5 Mw/Mn 2.6 2.6 2.6 11 5.9 4.9 HMWF(,) 25.3 25.3 25.3 8.2 4.7 0 熔化熱(J/g) 111.6 111.6 111.6 103.3 94.6 88.9 質量% 10 10 10 10 10 10 聚烯烴組成物的濃度質量％ 25 25 25 25 25 25 第二個聚烯烴 PB1 Mw 3.0 χ 105 3.0 χΙΟ5 3.0 χ ΙΟ5 3.0 χ ΙΟ5 3.0 χ ΙΟ5 3.0 x10s Mw/Mn 8.6 8.6 8.6 8.6 8.6 8.6 質量％ 47 47 47 47 47 47 PE2 Mw 2.0 xlO6 2.0 χΙΟ6 2.0 χΙΟ6 2.0 χΙΟ6 2.0 χ ΙΟ6 2.0 xlO6 Mw/Mn 8 8 8 8 8 8 質量％ 3 3 3 3 3 3 PP Mw 1.40 xlO6 1.40 χ ΙΟ6 1.40 χ ΙΟ6 1.40 χ ΙΟ6 1.40 χΙΟ6 1.40 χ ΙΟ6 Mw/Mn 2.6 2.6 2.6 2,6 2.6 2.6 HMWF 0) 25.3 25,3 25.3 25.3 25.3 25.3 熔化熱(J/g) 111.6 111.6 111.6 111.6 111.6 111.6 質量％ 50 50 50 50 50 50 聚烯烴組成物的濃度質量％ 35 35 35 35 35 35 製造條件 擠出物 層結構⑵ ⑴/(11)/(1) ⑴/(11)/(1) (1)/(11)/(1) ⑴/(11)/(1) ⑴/(ny(i) (1)/(11)/(1) 層厚度比 40/20/40 40/20/40 25/50/25 40/20/40 40/20/40 40/20/40 凝膠狀片狀物的拉伸 溫度（°C) n) 118 118 118 118 118 118 倍率（MDxTD) 3 5x5 5x5 5x5 5x5 5x5 5x5 乾燥膜的拉伸 溫度（eC) 125 - 125 125 125 125 倍率（TD) 1.4 * 1.4 1.4 1.4 1.4 熱固定處理 溫度) 125 125 125 125 125 125 時間（分鐘） 10 10 10 10 10 10 性質 平均厚度(#m) 19.9 21.0 20.0 20.5 20.4 20.4 厚度的標準偏差(Am) 0.61 0.66 0.59 2.11 2.49 3.58 透氣率（sec/100cm3/2(Vm) 220 315 502 203 215 194 孔隙率％ 51.9 49.9 48.2 53.2 53.4 52.6 接脚耐屋強度（mN/20/m) 3150 3010 2930 3050 3000 2950 熱壓縮後的厚度變動率％ •10 -13 -11 -9 -10 •12 熱壓縮後的透氣率 435 630 980 410 430 400 電解溶液吸收速度 3.4 2.1 3.6 2.2 2.1 1.9 關閉溫度π 135 135 135 135 135 135 熔融溫度11 178 178 ISO 177 \V 176 電容量回復率％ 78 77 78 77 76 70 -64- 200920595 表1 (續) 編號 實施例7 實施例8 實施例9 實施例10 樹脂組成物 第一個聚烯烴 PEI Mw 3.0 x10s 3.0 xlO5 3.0 x10s 3.0 x10s Mw/Mn 8.6 8.6 8.6 8.6 質量％ 82 82 90 82 PE2 Mw 2.0 x!06 2.0 xlO6 - 2.0 xlO6 Mw/Mn 8 8 - δ 質量％ 8 8 - 8 pp Mw 1.40 xlO6 1.40 χ10δ 1.40 xlO6 1.40 xlO6 Mw/Mn 2.6 2.6 2.6 2.6 HMWF ⑴ 25.3 25.3 25.3 25.3 熔化熱(¼) 111.6 111.6 111.6 111.6 質量％ 10 10 10 10 聚烯烴組成物的濃度質量％ 25 25 25 25 第二個聚烯烴 PEI Mw 3.0 χ 105 3.0 χ ΙΟ5 3.0 xlO5 3.0 χΙΟ5 Mw/Mn 8.6 8.6 8.6 8.6 質量％ 47 47 47 50 PE2 Mw 2.0 xlO6 2.0 χΙΟ6 2.0 χ ΙΟ6 - Mw/Mn 8 8 8 - 質童％ 3 3 3 - PP Mw 0.90 χ ΙΟ6 2.69 χ ΙΟ6 1.40 χ ΙΟ6 1.40 χ ΙΟ6 Mw/Mn 2.4 3.8 2.6 2.6 HMWF (1) 10.8 57.2 25.3 25.3 熔化熱(J/g) 109.7 99.9 111.6 111.6 質量％ 50 50 50 50 聚烯烴組成物的濃度質量％ 35 35 35 35 製造條件 擠出物 n、 層結構⑵ (Ι)/(聊） (iy(ny(i) mmi) (1)/(11)/(1) 層厚度比 40/20/40 40/20/40 40/20/40 40/20/40 凝膠狀片狀物的拉伸 118 118 118 118 溫度（C ) 倍率（MDxTD：^ 5x5 5x5 5x5 5x5 乾燥膜的拉伸 溫度（t) 125 125 125 125 倍率（TO) 1.4 1.4 1.4 1.4 熱画定處理 125 125 125 125 溫度（Ο 時間（分鐘） 10 10 10 10 性質 平均厚度(//m) 19.3 19.9 19.5 20.2 厚度的標準偏差(私m) 0.61 0.60 0.53 0.60 透氣率（sec/100cm3/2(Vm) 188 330 231 208 孔隙率％ 53.1 48.2 52.4 52.1 接腳耐壓強度(mN_m) 3100 3300 3210 3220 熱壓縮後的厚度變動率％ -8 -7 •10 .12 熱懕縮後的透氣率 389 660 480 440 電解溶液吸收速度 3.5 2.9 3.5 3.3 關閉溫度t 135 135 135 135 熔融溫度*c 175 176 177 178 電容量回復率％ 78 77 81 80 -65- 200920595 表2 編號 比較實施例1 比較實施例2 比較實施例3 比較實施例4 比較實施例5 樹脂組成物 窠一個聚烯烴 PEI Mw Mw/Mn 質量％ PE2 Mw Mw/Mn 質量％ PP Mw Mw/Mn HMWF ⑴ 熔化熱(J/g) 質量％ 聚烯烴組成物的濃度質量％ 3.0 X 105 8.6 82 2.0 xlO6 8 18 25 - 3.0 xlO5 8.6 82 2.0 xlO6 8 8 6.8 χ ΙΟ5 5.9 8.4 94.6 10 25 3.0 xlO5 8.6 82 2.0 χΙΟ6 8 8 1.56 χ ΙΟ6 3.2 1.2 78.4 10 25 3.0 xlO5' 8.6 82 2.0 χΙΟ6 8 18 25 第二個聚烯烴 PHI Mw Mw/Mn 質量％ PE2 Mw Mw/Mn 質量％ PP Mw Mw/Mn HMWF(l) 熔化熱(J/g) 質量％ 聚烯烴組成物的濃度質量％ 3.0 xlO5 8.6 47 2.0 xlO6 δ 3 1.40 χ 106 2.6 25.3 111.6. 50 35 3.0 χ 105 8.6 47 2.0 xlO6 8 3 1.40 χ 106 2.6 25.3 111.6 50 35 3.0 χΙΟ5 8.6 47 2.0 χΙΟ6 8 3 6.8 χ ΙΟ5 5.9 8.4 94.6 50 35 3.0 χΙΟ5 8.6 47 2.0 χΙΟ6 8 3 1,56 χΙΟ6 3.2 1.2 78.4 50 35 - 製造條件 擠出物⑺ 層結構⑵ 層厚度比 (1)/(11)/(1) 40/20/40 (II) 100 (1)/(11)/(1) 40/20/40 (1)/(11)/(1) 40/20/40 (I) 100 凝膠狀片狀物的拉伸 溫度m ⑶ 倍率（MDxTD)W 118 5x5 118 5x5 118 5x5 118 5x5 115 5x5 乾燥膜的拉伸 溫度（t) 倍率（TD) 125 1.4 125 1.4 125 1.4 125 1.4 125 1.4 熱固定處理 溫度CC) 時間（分鐘） 125 10 125 10 125 10 125 10 127 10 性質 平均厚度(/m) 20.3 20.2 19.1 19.6 20.3 厚度的標準偏差(；/m) 0.39 0.54 2.33 1.13 0.41 透氣率（sec/100cm3/2〇Mm) 360 430 100 690 370 孔隙率％ 47.8 45.2 58.6 48.2 39 接脚耐屋強度_/20/m) 3210 3420 1710 1280 4410 熱壓縮後的厚度變動率％ -20 -11 -17 -20 -21 熱壓縮後的透氣率 880 820 210 1650 830 電解溶液吸收速度 1.2 2.4 2.7 1.6 1 關閉溫度它 135 135 135 135 135 熔融溫度它 177 179 162 160 148 電容量回復率％ 67 81 73. 73 65 -66 - 200920595 (1) HMWF表示分子量爲i.8xl〇6或更大（質量％) 之高分子量部分。 (2) (I)示第一個聚烯烴溶液，而（II)示第二個 聚烯烴溶液。 (3) (MDxTD)示縱向方向（MD)及橫斷方向（ TD )的倍率。 由表1可注意到，本發明之多層微多孔膜具有均衡的 性質，包括厚度的標準偏差、透氣率、接腳耐壓強度、關 閉溫度以及熔融溫度，還有極佳的電解溶液吸收，在熱壓 縮後的厚度及透氣率變動小。包含本發明之多層微多孔膜 之鋰離子二次電池具有70 %或更高的電容量回復率，表示 其具有所要的高溫抗衰減性質。 另一方面，比較實施例的微多孔膜產物呈現出較差的 性質平衡。 本發明之多層微多孔膜具有均衡的性質且如是多層微 多孔膜作爲電池隔板的用途提供了具有極佳安全性、耐熱 1生 '抗衰減性質及生產性的電池。 【圖式簡單說明】 第1圖係示典型D S C曲線之一例的圖。 第2圖係示典型D S C曲線之另一例的圖。 第3圖係示與第2圖相同之GPC曲線的圖’其中高 分子量的部分加了斜線。 -67- 200920595 第4圖係示典型TMA測量之一例的圖，關閉溫度以 箭頭顯示。 -68-Perkin Elmer Inc. The sample holder is sampled in a nitrogen atmosphere at 190 ° C for 10 minutes to heat the PP sample. At a rate of °C / min, cool to 40 ° C, keep at 4 (TC clock), and heat to 190 ° C at 10 ° C / min. As indicated, pass 85 ° C and The line at the point on the DSC curve (melting curve) obtained by the temperature rise process at 175 ° C can be plotted as a baseline, and the amount can be obtained from the sloped portion surrounded by the baseline and the DSC curve, the region S 1 . :g) Divided by the amount of heat (unit: J to determine the heat of fusion ΔΗιη (unit: J/g). The molecular weight is 1. The partial fraction of polypropylene (based on mass) of 8xl06 or less can be measured as follows. The amount of the propylene sample can be measured by measuring the curve in Fig. 2 and the oblique line portion around the base clue, region S2. The area S 3 in Fig. 3 can be measured to determine the amount of the molecular weight of 1·8χ106 or more. The amount is 1. The percentage of the 8x1 〇6 or larger portion is calculated from (S3/S2) (% by mass). [2] Substances used in the manufacture of multilayer microporous polyolefin membranes. The polymer resin used to make the first microporous layer material is in a system in which the first microporous layer material is made from the first polymer liquid. The first polyolefin solution comprises a first polyolefin group and a first processing solvent. Since this process produces a multi-layered microporous material, the processing solvent is also referred to as a diluent or film forming solvent. The resin of the first polyolefin composition of the stomach will be described in more detail below, in the calculation of the heat of ίλ1 0 2 1 1 ), the 100 GPC poly-molecular xl 00 olefin-forming film, -18- 200920595 (1) The first polyethylene resin in a system, the first polyethylene resin contains the first polyethylene 'the first polyethylene is as described in the previous paragraph π]. For example, the first polyethylene resin may be a mixture of a polyethylene resin having a lower Mw than UHMWPE (such as 'HDPE) and a UHMWPE resin. The molecular weight distribution (Mw / Μη) of the polyethylene in the first polyethylene resin is not strictly limited. Mw / Μη is a measure of the molecular weight distribution, and the larger the enthalpy, the broader the molecular weight distribution. Although not strictly limited, the polyethylene Mw / Μη in the first polyethylene resin may range from about 5 to about 300, or from about 5 to about 1 Torr, or from about 5 to about Within the range of 3 0 . When Mw/Mn is less than 5, it is more difficult to extrude the first polyethylene resin. On the other hand, when Mw / Μη is more than 300, it is more difficult to produce a relatively strong multilayer microporous film. A multistage polymerization process can be used to obtain the Mw / Μη in the first polyethylene resin desired. For example, a two-stage polymerization process can be employed to form a relatively high molecular weight polymer component in the first stage and a relatively lower molecular weight polymer component in the second stage. Although not essential, for example, when the first polyethylene resin contains Ρ Ε 1, this method can be employed. When the first polyethylene resin contains ruthenium 1 and ruthenium 2, the Mw / Μ η ratio of the desired polyethylene resin can be selected by adjusting the relative molecular weights and relative amounts of the first and second polyethylenes. (2) First polypropylene resin -19- 200920595 In addition to the first polyethylene resin, the first polyolefin contained the first polypropylene resin. In a system, the first fat comprises a first polypropylene, wherein the first polypropylene is described in paragraph π]. The first polypropylene resin may be a plurality of (i) a polypropylene homopolymer or (ii) a propylene and a fifth alkene. The copolymer can be a clutter or block copolymer. The fifth, for example, one or more α-olefins (such as ethylene, butene: hexyl-1, 4-methylpentene oxime, octene oxime, vinyl acetate acetoacetate, and benzene) Ethylene, etc.): and the amount of the fifth olefin of the diolefins (1,5-hex-ene, anthracene, 7-octadiene, anthracene, 9-decadiene, etc.) should not be The microporous film such as 'heat resistance, pressure resistance, heat shrinkage resistance, and the like) is negative. For example, the amount of the fifth suspected hydrocarbon may be less than 1 mole % (the entire copolymer of the ear %). Although not strictly limited, the Mw in the first polypropylene resin may range from ', for example, from about 1 χ1〇4 to about 4χ1〇6, from 0.05 to about 3 X 1 0 6 . Although not strictly limited, the molecular weight distribution (Mw / Μη) of the polypropylene in the first resin may be in the range of about 100 Å, or about i" to about 5 Å. (3) Formulation The amount of the processing solvent in the first polyolefin solution may range from 25 wt% to about 99 wt% (based on the first polygrain). In a system, the hydrocarbon composition in the first polyolefin composition is further a polypropylene tree. For example, the copolymer olefin of one or a hydrocarbon may be ί, -1-1, methacryl, for example. Butadiene. The nature of the copolymer (the range of influences is based on 100 moles of polypropylene, or about 3 Χ a polypropylene 匕 about 1 · 0 1 to, for example, the first poly-20 of the olefin solution - 200920595 The amount of the resin may range, for example, from about 50% by weight to about 99% by weight based on the weight of the first polyolefin composition. The remainder of the first polyolefin composition is the first polymer. Propylene. The polymer resin used to make the second microporous layer material is in a system, and the second microporous layer material is from the second polysulfide solution (the selection system is independent of the first polyolefin solution) Made. The second polyolefin solution comprises a second polyolefin composition and a second processing solvent (this solvent can be the same as the first processing solvent). As in the case of the first polyolefin solution, the second processing solvent can be referred to as a second film forming solvent or a second diluent. In one system, the second polyolefin composition comprises a second polyethylene resin and a second polypropylene resin. The second polyethylene resin may comprise the second polyethylene resin described in the above paragraph [1]. The second polypropylene resin comprises the second polypropylene described in the above paragraph [1]. The amount of processing solvent in the second polyolefin solution may range from about 25 wt% to about 99 wt% based on the weight of the second polyolefin solution. In one system, the amount of the second polyethylene resin in the second polyolefin composition can range, for example, from about 5% by weight to about 95% by weight based on the weight of the second polyolefin composition. . The remainder of the second polyolefin composition can be a second polypropylene. C. Although the third polyolefin is not necessary, the first and second polyolefin compositions may each comprise a third polyolefin selected from the group consisting of polybutene-1, polypentene- i, poly-4-methylpentene-1, polyhexene-1, polyoctene-1, polyvinyl acetate, polymethyl methacrylate, polystyrene and ethylene olefin copolymer (except ethylene-propylene In addition to the copolymer). In the system in which the third polyolefin is used, the third polyolefin may, for example, have a Mw in the range of from about 1 x 4 to about 4 x 10 Å. In addition to the third olefin, the first and/or second polyolefin composition may further comprise a polyethylene wax, for example, having a Mw in the range of from about 1 x 10 3 to about 1 x 10 Torr. When used, such species should be present in an amount less than would cause the desired properties (e.g., melting, shutdown, etc.) of the multilayer microporous membrane to deteriorate. When the third polyolefin is one or more of the following: polybutene-1, polypentene-1, poly-4-methylpentene-1, polyhexene-1, polyoctene-1, poly Vinyl acetate, polymethyl methacrylate, and polystyrene, the third polyolefin need not be a homopolymer, but may be a copolymer containing other α-olefins. Multilayer microporous membranes typically comprise a polyolefin for forming a polyolefin solution. It is also possible that a small amount of cleaning solvent and/or processing solvent is present, which is usually less than 1% by weight (based on the weight of the microporous polyolefin film). A small amount of polyolefin molecular weight reduction may occur during processing, but this is acceptable. In a system, if the molecular weight decreases during the processing, the Mw/Mn number of the polyolefin in the film is different from the Mw / η η of the first or second polysulfide solution. About 50%, or no more than about 1%, or no more than about 0. 1 %. [3] Method for producing multilayer microporous polyolefin film -22- 200920595 In a system, the microporous polyolefin film is a two-layer film. In another embodiment, the microporous polyolefin membrane has at least three layers. For the sake of brevity, the manufacture of microporous polyolefin membranes will mainly be described by two-layer and three-layer membranes, but it is recognized by those skilled in the art that the same technique can be applied to membranes or membranes having at least four layers. Manufacturing. In one system, the three-layer microporous polyolefin film comprises first and third layers of microporous layers constituting the outer layer of the microporous polyolefin film, and is located between the first and third layers (and optionally with The second layer, which is in a plane contact. In one system, the first and third layers are produced from a first polyolefin solution and the second layer (inner layer) is produced from a second polyolefin solution. In another system, the first and third layers are produced from a second polyolefin solution and the second layer is produced from a first polyolefin solution. A. First Manufacturing Method The first method of producing a multilayer film comprises the steps of: (1) preparing a first polyolefin composition and a film forming solvent (for example, by melt blending) to prepare the first a polyolefin solution, (2) combining a second polyolefin composition with a second film forming solvent to prepare a second polyolefin solution, and (3) making the first and second polyolefin solutions (suitable) To simultaneously extrude through at least one mold to form an extrudate, (4) to cool the extrudate to form a cooled extrudate 'eg, a multi-layer gel-like sheet, (5) from the The multilayer sheet removes the film forming solvent to form a solvent-removed sheet 'and (6) the solvent-depleted gel-like sheet is dried' to remove any volatile species present, To form a multi--23-200920595 layer microporous polyolefin film. Optionally, between steps (4) and (5), a selective stretching step (7) and a selective thermal solvent treatment step (8) may be performed. If necessary, after step (6), a selective step (9) of stretching the multilayer microporous membrane, a selective heat treatment step (10), and a selective crosslinking step (1 1 ) using free radiation may be performed. And an optional hydrophilic treatment step (12) and the like. The order of the selective steps is not strictly limited. (1) Preparation of First Polyolefin Solution The first polyolefin composition comprises the above-mentioned polyolefin resin which can form a solvent with a suitable film, for example, by dry mixing or melting, The first polyolefin solution is produced. Optionally, the first multi-dilute hydrocarbon solution may contain various additives such as one or more of the following: an antioxidant, a fine cerium oxide powder (a substance forming a pore), etc. 'Prerequisites are · used by them The concentration range does not significantly reduce the desirable properties of the multilayer microporous polyolefin film. The first processing solvent (i.e., the first film forming solvent) is preferably a solvent which is liquid at room temperature. While not wishing to be bound by any theory or mode, it is believed that the use of a liquid solvent to form the first polyolefin solution is likely to effect stretching of the gelatinous sheet at relatively high draw ratios. The first film forming solvent in a system may be at least one of the following: aliphatic, alicyclic or aromatic hydrocarbons such as 'decane, decane, decahydronaphthalene, p-xylene, undecane , dodecane, liquid paraffin, etc.; mineral oil distillate having a boiling point comparable to the aforementioned hydrocarbons; and citrate liquid at room temperature '24-24 200920595 eg dibutyl phthalate, dioctyl citrate Ester and so on. In a system for obtaining a multi-layered knee-like sheet having a stable liquid solvent content, a non-volatile liquid solvent such as liquid paraffin may be used alone or in combination with other solvents. Alternatively, a solvent which is miscible with polyethylene in a molten blending state but which is solid at room temperature may be used, which may be used alone or in combination with a liquid solvent. The solid solvent may include, for example, stearyl alcohol, cetyl alcohol, paraffin wax or the like. Although not strictly limited, it is more difficult to stretch the gel-like sheet or the obtained film evenly when the solution does not contain a liquid solvent. The viscosity of the liquid solvent is not a decisive parameter. For example, the viscosity of the liquid solvent can range from about 30 cSt to about 500 cSt, or from about 30 cSt to about 200 cSt (25 °C). Although it is not a decisive parameter, it is more difficult to prevent foaming of the polyolefin solution (which causes difficulty in blending) when the viscosity at 25 ° C is less than about 30 cSt. On the other hand, when the viscosity is more than about 500 cSt, it is more difficult to remove the liquid solvent from the multilayer microporous polyolefin film. In a system, a resin or the like for producing the first polyolefin composition is, for example, a twin roll extruder or a mixer, and is subjected to dry mixing or melt blending. For example, a conventional extruder (or mixer or mixer-extruder), such as a two-roll extruder, can be used to knead a resin or the like to form a first polyolefin composition. A film forming solvent may be added to the polyolefin composition (or alternatively added to the resin used to produce the polyolefin composition) at any convenient point in the process. For example, when the first olefin composition is melt blended with the first film forming solvent, the solvent can be -25-200920595 before (i) starting the melt blending, (π) in the first polyolefin group. Adding to the polyglycol composition (or a component thereof) at any point after the melt blending of the product, or (iii) after melt blending, for example, by a second if® machine or located for melting The addition of the first film forming solvent to the melt-blended or partially melt-blended polyolefin composition is carried out in the region of the extruder downstream of the extruder zone blended with the polyolefin composition. # $ m 'When melt blending, there is no strict limit on the melt blending temperature. For example, the melt blending temperature of the first polyglycol solution can be higher than the melting point of the first polyethylene resin. (The temperature of TC is in the temperature range of about 120 °C higher than Tmi. For the sake of brevity, the range can be expressed as Tim + lOt: to Tm + 12 (rc. The melting point of the first polyethylene resin) In systems having a temperature of from about 130 ° C to about 1 40 ° C, the melt blending temperature may range from about 140 ° C to about 250 ° C, or from about 170 ° C to about 2 4 01: In the range. When an extruder (such as a two-roll extruder) is used for melt blending, the parameters of the roll are not strictly limited. For example, the roll may be characterized by: double squeeze The ratio L / D of the roll length L of the press to the roll diameter D may be in the range of, for example, about 20 to about 1 Torr, or about 35 to about 70. Although this parameter is not strictly limited, 'Melting blending will be more difficult when L / D is less than about 20, and when l/D is greater than about 100, faster extruder speeds may be required to prevent polyolefin solution The residence time in the twin roll extruder is too long (this will result in undesirable molecular weight reduction). Although not a decisive parameter, the extrusion barrel (or orifice) of the twin roll extruder can have, for example, Inner diameter in the range of 40 mm to about 1 mm. -26- 200920595 The amount of the first polyolefin composition in the first polyolefin solution is not strictly limited. In one system, the first The amount of the first polyolefin composition in the polyolefin solution may range from about 1% by weight to about 75% by weight (based on the weight of the polyolefin solution), for example, from about 20% by weight to about 70% by weight. Although the amount of the first polyolefin composition in the first polyolefin solution is not strictly limited, when the amount is less than about 1% by weight, it will be more difficult to produce a multilayer microporous at an acceptable sufficient rate. Polyolefin film. Further, when the amount is less than 1% by weight, it is more difficult to prevent swelling or narrowing at the exit of the mold during extrusion, and it is difficult to form and support the multilayer gel-like sheet (which is a manufacturing process) Precursor of the film formed during the period). In one aspect, when the amount of the first polyolefin composition in the first polyolefin solution is more than 75 wt%, it will be more difficult to form a multilayer gel-like sheet. The amount of the first polyethylene resin is preferably 1 to 50% by mass, more preferably 20 to 40% by mass (relative to the first polyolefin solution per 1% by mass). When the polyethylene resin is less than 1% by mass, the first olefin is used During the extrusion of the solution to form a gel-like molded product, expansion or narrowing occurs at the exit of the mold, resulting in a decrease in moldability and self-supporting property of the gel-like molded product. On the other hand, when the polyethylene resin is less When the amount is 50% by mass, the moldability of the gel-like molded product deteriorates. (2) Preparation of second polyolefin solution The second polyolefin solution can be produced by the same method as that used in the preparation of the first polyolefin solution. For example, a second polyolefin solution can be prepared by melt blending a second polyolefin composition with a second film forming solvent, -27-200920595. The second film forming solvent may be selected from the same solvent as the first film forming solvent. Although the second film forming solvent may (and usually is) independently selected from the first film forming solvent 'however, the second film forming solvent may be the same as the first film forming solvent, and may form a solvent with the first film It is used for the same relative concentration of the first polyoxo solution. The second polyolefin composition is typically independently selected from the first polyolefin composition. The second polyolefin composition comprises a second polyethylene resin and a second polypropylene resin. The method for preparing a second polyolefin solution in a system differs from the method for preparing the first polyolefin solution in that the mixing temperature is preferably at the melting point (Tm2) to Tm2 + 90 ° C of the second polypropylene. The amount of the polyolefin composition is preferably in the range of 1 to 50% by mass 'more preferably 20 to 40% by mass. (3) extrusion in a system, the first polyolefin solution is guided by the first extruder to the first mold, and the second polyolefin solution is guided by the second extruder to the first Two molds. From the first and second dies, the delaminated sheet-like extrudate (i.e., an object having a substantially larger planar direction than the thickness direction) can be extruded. Optionally, the first and second polyolefin solutions are coextruded from the first and second molds such that the planar surface of the first extrudate layer formed by the first polyolefin solution The planar surface of the second extrudate layer formed by the second polyolefin solution is in contact. The planar surface of the extrudate can be defined by a first vector in the machine direction of the extrudate and a second vector in the transverse direction of the extrudate. -28- 200920595 In a system, a module can be used, in which a die assembly includes a first mold and a second mold, for example, when the first mold and the second mold are shared in the module. The same compartment containing the first polyolefin solution and the second zone containing the second polyolefin solution in the module. In another system, multiple molds can be used, each mold being attached to an extruder to direct the first or second polyolefin solution to the mold. For example, in one system, the first extruder containing the first polyalkylene solution is connected to the first mold and the third mold' and the extruder containing the second polyoxo solution is Connect to the second mold. As in the case of the foregoing system, the resulting layered extrudate can be coextruded (e.g., simultaneously) from the first, second, and third molds to form a three layer extrudate. And a first layer and a third layer (for example, a top layer and a bottom layer) constituting the surface layer formed of the first polyolefin solution, and an intermediate layer constituting the extrudate and located between and between the two surface layers A second layer in planar contact wherein the second layer is formed from a second polyolefin solution. In yet another system, the same module is used, but the polyolefin solution is reversed, that is, the second extruder containing the second polyolefin solution is connected to the first mold and the third The mold, and the first extruder containing the first polyolefin solution is attached to the second mold. In any of the foregoing systems, conventional die extrusion equipment can be used for die extrusion. For example, the extrusion can be performed by a flat die or an inflation die. In a system that can be used to coextrude a multi-layered gel-like sheet, a multi-manifold -29-200920595 extrusion can be employed in which the first and second poly-saturated hydrocarbon solutions are introduced. The individual manifolds of the multi-layer extrusion die are layered on the lip outlet. In another system, a block extrusion method may be employed in which the first and second polyolefin solutions are first combined into a laminar flow (i.e., previously), and then the laminar flow can be connected to Mold. Since the multi-port extrusion method and the block extrusion method are known to those skilled in the art of polyolefin film processing, for example, as disclosed in JP06-122142 A, JP 06-106599 A, they are Methods are considered as learners and their operation methods are not described in detail. The selection of the mold is not strictly limited, and for example, a flat mold or an inflatable mold which is conventionally used to form a multi-layer sheet can be used. The mold gap is not strictly limited. For example, a flat mold forming a multi-layer sheet may have a mold gap of from about 1 m to about 5 mm. The mold temperature and extrusion speed are also not strictly set parameters. For example, during extrusion, the mold can be heated to a mold temperature in the range of from about 140 °C to about 250 °C. The extrusion speed can be, for example, about 0. 2 m / min to about 15 m / min. The layer thickness of the layered extrudate can be selected independently. For example, the gelatinous layer may have a relatively thick surface layer (or "skin" layer) (compared to the thickness of the intermediate layer of the layered extrudate). Although extrusion has been produced by The system of the two- and three-layer extrudates is described, but the extrusion step is not limited to the systems. For example, a plurality of molds and/or modules may be used, and the method described in the above system may be used to manufacture Four or more layers of multilayer extrudate. In such a layered extrudate, each surface or intermediate layer can be made using a first polyolefin solution and/or a second polyolefin solution. -30- 200920595 (4) Formation of Multilayer Gel-like Sheet The multilayered extrudate can be formed into a multi-layered condensed sheet by, for example, cooling. The cooling rate and the cooling temperature are not particularly strictly limited. For example, multilayer The gelatinous sheet may be cooled to a temperature of the multilayer gel-like sheet (cooling temperature) at a cooling rate of at least about 50 ° C /min to be approximately equal to the gelation temperature of the multilayer gel-like sheet ( Or lower temperature). In one system, the extrudate system Cooling to a temperature of about 25 ° C or lower to form a multi-layer gel-like sheet. Although not wishing to be bound by any theory or mode, it is believed that the cooling of the layered extrudate is determined by one Or a plurality of membrane forming solvents to separate the polyolefin microphases of the first and second polyolefin solutions. It has been observed that, in general, a slower cooling rate (eg, less than 50 ° C / min) is provided. A multi-layered gel-like sheet with a larger pseudocell unit, resulting in a coarser higher-order structure. On the other hand, a relatively fast cooling rate (for example, 80 °) C / min) will result in a dense cell unit. Although not a decisive parameter, when the cooling rate of the extrudate is less than 50 ° C / min, the crystallinity of the polyolefin in the layer will increase. The processing of the multi-layered gel-like sheet in the subsequent stretching step is difficult to carry out. The selection of the cooling method is not strictly limited. For example, a conventional sheet cooling method can be employed. The cooling The method comprises contacting the layered extrudate with a cooling medium such as 'cooling air, cooling water, etc.. Alternatively, the extrudate may be optionally cooled by contact with a cooling medium such as a cooling medium. -31 - 200920595 (5) Removal of the first and second film-forming solvents in a system - removal (or substitution) of at least a portion of the first and second film formations from a multilayer gel-like sheet a solvent to form a gel-like sheet from which the solvent has been removed. A substitution (or "cleaning" solvent) can be used to remove (wash off, or replace) the first and second film forming solvents. Bound to any theory and mode, but we believe that because the polyolefin phase in the multilayer gel-like sheet produced by the first polyolefin solution and the second polyolefin solution is separated from the film forming solvent, Therefore, the removal of the film forming solvent provides a porous film composed of fibrils which form a fine three-dimensional network structure and have pores which are three-dimensionally and irregularly communicated. The choice of cleaning solvent is not critical as long as it is capable of dissolving or replacing at least a portion of the first and/or second film forming solvent. Suitable cleaning solvents include, for example, one or more volatile solvents such as saturated hydrocarbons such as 'pentane, hexane, heptane, etc.; chlorinated hydrocarbons such as 'dichloromethane' tetrachloride Carbon or the like; ethers such as diethyl ether, dioxane, etc.; ketones such as methyl ethyl ketone and the like; linear fluorocarbons such as trifluoroethane, C6F14, C7F16, etc.; Hydrofluorocarbons such as 'C5H3F7 and the like; hydrofluoroethers such as C4F9〇CH3, C4F9〇C2H5 and the like; and perfluoroether compounds such as C4F9〇CF3, c4f9oc2f5 and the like. The method of removing the film forming solvent is not critical, and any method capable of removing a significant amount of the solvent may be employed, including a conventional solvent removal method. For example, the multilayer gel-like sheet can be washed by immersing the multilayer gel-like sheet in a washing solvent and -32-200920595 or by washing with a washing solvent. The amount of cleaning solvent used is not critical and is generally dependent upon the method chosen to remove the film forming solvent. For example, the amount of cleaning solvent used can range from about 300 to about 30 Å by mass based on the mass of the gelatinous sheet. Although there is no particular strict limit on the amount of solvent for forming a film, when at least a large amount of the first and second film forming solvents are removed from the gel-like sheet, it usually causes a higher quality. A (more porous) film is produced. In a system, the film forming solvent is removed from the gel-like sheet (for example, by washing) until the amount of remaining film forming solvent in the multilayer gel-like sheet becomes less than 1% by weight (based on the gel The weight of the sheet is as long as it is. (6) drying the gel-like sheet from which the solvent has been removed in a system, and drying the solvent-removed multilayer gel-like sheet obtained by removing at least a part of the film forming solvent to remove the cleaning solvent . Any method capable of removing the cleaning solvent may be employed, including conventional methods such as heat drying, air drying (moving air) and the like. The temperature of the gelatinous sheet during drying (i.e., the drying temperature) is not strictly limited. For example, the drying temperature may be equal to or lower than the crystal dispersion temperature Ted. Ted is the lower of the crystal dispersion temperature Tcdi of the first polyethylene resin and the crystal dispersion temperature Tcd2 of the second polyethylene resin (if used). For example, the drying temperature can be at least 5 ° C lower than the crystal dispersion temperature Ted. The crystal dispersion temperature of the first and second polyethylene resins can be determined by measuring the temperature characteristics of the dynamic viscoelasticity of the polyethylene resin according to ASTM D 4065. At least one of the first or second resins in a system has a dispersion temperature in the range of from about 90 ° C to about 10 ° C. Although not strictly set, the drying can be carried out until the remaining cleaning solution is about 5% by weight or less (dry basis, i.e., the weight of the base multilayer microporous polyolefin film). In another system, the amount of the remaining cleaning solvent is about 3% by weight or less (reference). Insufficient drying is identifiable because it generally increases the porosity of the multilayer microporous membrane undesirably. If observed, increase the drying temperature and / or increase the drying time. Removal of the cleaning solvent by 'dry' or other methods can result in the production of a multilayer polyolefin film. (7) Stretching Before the step of removing the film forming solvent (that is, the step 5 can stretch the multilayer gel-like sheet to obtain a stretched multilayered condensate. I believe that the multilayer gel-like sheet is The presence of the first and film forming solvent in the article can result in a relatively uniform stretching of the multi-layered gel-like sheet, especially at the beginning of stretching or at a relatively early stage (eg, at 50%) Before the stretching is completed), it contributes to the uniformity of stretching. Whether it is the choice of stretching method or the degree of stretching magnification, the setting is particularly strict. For example, any multilayer gel-like sheet can be extended to The method of predetermining the magnification (including any selective heating) 'the amount of the crystallizer of the polyethylene is dried in the drying process to cause this phenomenon, such as, before dry microporous," the second rate of the gelatinous sheet. The stretched ones are considered to be unexposed and can be used for -34- 200920595. In a system, it can be accomplished by one or more of the following: tenter-stretching, roller-stretching, or inflation stretching ( For example, use air). Although there are no strict limits on the selection, the stretching can be performed either uniaxially (i.e., in the machine or transverse direction) or dual axis (in the machine and transverse directions). In a system, biaxial stretching can be employed. In the case of biaxial stretching (also known as biaxial orientation), the stretching can be simultaneous biaxial stretching, first along a plane axis and then along another axis (ie, first in the transverse direction) The direction of the break is then in the machine direction, or the multi-stage stretching (for example, a combination of simultaneous biaxial stretching and continuous stretching). In a system, simultaneous biaxial stretching is employed. The draw ratio is not strictly limited. In the system using uniaxial stretching, the linear stretching ratio may be, for example, about 2 times or more, or about 3 to about 30 times. In the system using biaxial stretching, the linear stretching ratio may be, for example, about 3 times or more (in the plane direction). In another system, the area magnification resulting from stretching is at least about 9 times, or at least about 16 times, or at least about 25 times. Although not a decisive parameter, the multilayer microporous polyolefin film will have a relatively high pin compressive strength when stretching results in an area magnification of at least about 9 times. When an area magnification greater than about 400 times is reached, it will be more difficult to operate the stretching device. The temperature (i.e., stretching temperature) of the multilayer gel-like sheet during stretching is not strictly limited. In a system, the temperature of the gelatinous sheet during stretching may be about (Tm + 1 (TC) or lower, or alternatively in a range higher than Ted but lower than Tm, wherein Tm The first of the first polyethylene -35- 200920595 melting point Tmi and the second polyethylene (if used) melting point Tm2. Although this parameter is not strictly set, but when the stretching temperature is higher than At about the melting point Tm + 10 °c, at least one of the first or second polyethylene is in a molten state, which causes the orientation of the polyolefin molecular chains in the multilayer gel-like sheet to be more uniform during stretching. Difficult. And when the stretching temperature is lower than about Ted, at least one of the first or second polyethylene may not be sufficiently softened, and it is difficult to stretch the multilayer gel sheet without breaking or tearing. This results in failure to achieve the desired draw ratio. In one system, the draw temperature is in the range of from about 90 ° C to about 140 ° C, or from about 10 ° C to about 1 In the range of 30 °c. Although I do not want to be bound by any theory or model, I believe that if it is stretched The peeling between the thin layers of polyethylene makes the polyethylene phase more slender and forms a large amount of fibrils. These fibrils form a three-dimensional network structure (a three-dimensional irregularly connected network structure). Therefore, stretching ( If used, it is generally easier to manufacture a multilayer microporous polyolefin film having a relatively high mechanical strength and a relatively large pore size. A multilayer microporous film is considered to be particularly suitable as a battery separator. It can be carried out in the thickness direction (that is, in a direction approximately perpendicular to the plane surface of the multilayer microporous polyolefin film) under the temperature gradient. In this case, it is easy to manufacture a multilayer microporous polymer having improved mechanical strength. The olefin film. The details of this method are described in Japanese Patent No. 3347854. (8) Thermal solvent treatment step - 36 - 200920595 Although not essential, between steps (4) and (5), the multilayer solvent can be treated with a hot solvent. a gelatinous sheet. When used, we believe that the thermal solvent treatment can be provided for fibrils (such as 'formed by stretching a multilayer gel-like sheet) For a thick vein structure, this structure makes it relatively difficult to produce a multi-layer microporous membrane with large pores and relatively high strength and high permeability. The term "leaf vein" refers to the presence of fibrils. A thick backbone and a thin fiber extending from the network. The details of this method are described in WO 2000/2 0493. (9) Tensile ("dry stretching") of a multilayer microporous membrane in a system The dried multi-layer microporous film of the step (6) can be stretched at least uniaxially. There is no strict limit on the selected stretching method and a conventional stretching method can be employed, such as 'pulling by a tenter type Stretching, etc. Although there are no strict limits, the film can be heated during the stretching process. Although there are no strict restrictions on the choice ', the stretch can be uniaxial or biaxial. When biaxial stretching is employed, the stretching can be carried out simultaneously in both axial directions 'or alternatively, the multilayer microporous polyolefin film can be stretched in a continuous manner, for example, 'in the machine direction, then in the transverse direction. . In a system, the simultaneous biaxial stretching is employed. When the multilayer gel-like sheet has been stretched as described in the step (7), the stretching of the dried multilayer microporous polyolefin film of the step (9) is referred to as dry stretching, re-stretching or dry orientation. (dry_orientation) ° The temperature ("dry stretching temperature) of the dried multilayer microporous film during stretching is not strictly limited. In a system, the 'dry stretching temperature is -37-200920595 is approximately equal to the melting point Tm or Lower, for example, in the range of about the crystal dispersion temperature Ted to about the melting point Tm. When the dry stretching temperature is higher than Tm, it will be more difficult to produce a relatively high pressure resistance and have relatively uniform air permeability characteristics, Especially in the transverse direction (when the dried multilayer microporous polyolefin film is stretched in the transverse direction). When the stretching temperature is lower than T cd , it will be more difficult to sufficiently soften the first and second polyolefins, and It causes tearing during stretching and lacks uniform stretching. In a system, the drying stretching temperature may range from about 90 ° C to about 135 ° C, or from about 95 ° C to about 1 In the range of 30 ° C. When using dry stretching, stretching ratio No strict restrictions. For example, the stretching ratio of the multilayer microporous membrane (e.g., side) on at least one planar direction, can be about 1. 1 time to about 1. Within 8 times range. Therefore, in the case of uniaxial stretching, the stretching ratio in the longitudinal direction (i.e., the "mechanical direction" or the transverse direction (depending on the longitudinal or transverse stretching of the film system) may be about 1. 1x to about 1. Within 8 times range. Uniaxial stretching can also be accomplished along the plane axis between the longitudinal and transverse directions. In a system, the stretching ratio along the two stretching axes (for example, both in the longitudinal direction and the transverse direction) is about 1. 1x to about 1⁄8 times of biaxial stretching. The stretching ratio in the longitudinal direction need not be the same as the stretching ratio in the transverse direction. In other words, in the case of biaxial stretching, the stretching ratio can be independently selected. In one system, the dry draw ratios in the two directions of stretching are the same. (1 〇) Heat treatment In a system, the dried multilayer microporous membrane can be heat treated in accordance with step (6). It is believed that the heat treatment can be used to form a thin layer of a uniform sentence by drying the polyolefin microcrystals in the multilayer microporous poly-38-200920595 olefin film. In one embodiment, the heat treatment comprises heat setting and/or annealing. When heat setting is employed, it can be carried out using a conventional method such as a tenter method and/or a roller method. Although not strictly limited, the temperature of the dried multilayer microporous polyolefin film (i.e., "heat setting temperature") may range from Ted to about Tm during heat setting. In one system, the heat setting temperature may be within a range of about ± 5 t of the dry stretching temperature of the multilayer microporous polyolefin film, or within a dry stretching temperature of about 3 t of the multilayer microporous polyolefin film. Annealing differs from heat setting in that it is a heat treatment without applying a load to the multilayer microporous polyolefin film. The selection of the annealing method is not strictly limited, and it can be carried out by using, for example, a heating chamber equipped with a belt conveyor or an air floating heating chamber. Alternatively, the annealing can be carried out after heat setting (tenter clips are relaxed). The temperature (i.e., annealing temperature) of the multi-layer microporous polyolefin film is not strictly limited during annealing. In a system, the annealing temperature can be in the range of about the melting point Tm or lower, or in the range of about 6 (TC to (Tm-lOt). It is believed that annealing will result in a multilayer micro-layer having relatively high permeability and strength. The production of the porous polyolefin film is less difficult. (1 1 ) Cross-linking in a system, after the step (6), the multilayer microporous polyolefin film can be crosslinked (for example, by free radiation rays such as α) Ray, /3 ray, r ray, electron beam, etc.) For example, when using a radiant electron beam to crosslink, the amount of electron beam radiation can be about 0. 1 Mr ad to -39- 200920595 The acceleration voltage used in approximately 100 Mrad ' is in the range of approximately 100 kV to approximately 300 kV. It is believed that the cross-linking treatment will make the fabrication of the multilayer microporous polyolefin film having a relatively high melting temperature less difficult. (1 2) Hydrophilic treatment In a system, the multilayer microporous polyolefin film can be subjected to hydrophilic treatment (i.e., treatment for making the multilayer microporous polyolefin film more hydrophilic). The hydrophilic treatment may be, for example, a monomer graft treatment, a surfactant treatment, a corona treatment, or the like. In a system, after crosslinking treatment, monomer grafting treatment is employed. When a surfactant is employed, any nonionic surfactant, cationic surfactant, anionic surfactant, and zwitterionic surfactant can be used, for example, alone or in combination. In a system, a nonionic surfactant is used. There is no strict limit to the choice of surfactant. For example, a multilayer microporous polyolefin membrane can be immersed in a solution of a surfactant with water or a lower alcohol such as methanol, ethanol, isopropanol, etc. or, for example, by a casting method. The solution. B. A second method of manufacture for the manufacture of a multilayer microporous polyolefin film comprises the following steps: (1) combining the first polyolefin composition with a first film forming solvent (eg, by melt doping Legitimate) to prepare a first polyolefin solution ' (2) to combine a second polyolefin composition with a second film forming solvent' to prepare a second polyolefin solution, (3) to make the first poly Olefin Solution -40 - 200920595 Extrusion through the first die and extrusion of the second solution through the first, then the extruded first and second poly-burning hydrocarbon solution, resulting in multilayer extrusion And (4) cold-forming the multilayer extrudate to form a multi-layer gel-like sheet' (5) from the multi-layer gel-like sheet, except for at least part of the film forming solvent, to form a solvent-depleted condensate, and (6) The solvent-like gel-like sheet is removed to form a multilayer microporous membrane. An optional stretching step (7) and an optional thermal solvent (8) and the like may be carried out at step (4) and between as needed. After step (6), an optional step (9) of stretching the porous membrane, an optional heat treatment step (1 〇), an optional step (1 1 ) of crosslinking by irradiation, and an optional hydrophilic step may be performed. (1 2) and so on. The process steps and conditions of the second manufacturing process are generally the same as those described in the section having the manufacturing steps, except 3). Therefore, step (3) will be explained in detail. There is no strict limit to the mold used, as long as the mold forms a laminate extrudate. In a system, the articles are formed using sheets (they are adjacent or joined together) to form an extrudate. And a second sheet mold is attached to the first and second, respectively, wherein the first extruder contains a first polyolefin solution and the first press contains a second polyolefin solution. Although not strictly limited, the extruded first and second polyolefin solutions are still relatively easy to laminate when still about extruded. Other conditions can be the same as in the first. The mold rows are laminated, and the objects are dried to the gel-like sheet. (5) The treatment step layer is slightly treated with freeness to close the first step (the first extruder can be used to mold the two extruders but when Temperature Next Method -41 - 200920595 In another system, the first, second and second sheet molds are connected to the first, second and third extruders. And the third sheet mold contains the first polyolefin solution 'and the second sheet mold contains the second polyolefin solution. In this system, the formed laminated extrudate system Formed by an outer layer comprising the first extruded polystyrene solution and an intermediate layer comprising the extruded second polyolefin solution. In yet another system, the first, second, and third sheets The mold is connected to the first, second and third presses, wherein the second sheet mold contains the first polyolefin solution and the first and third sheet molds And a second polyolefin solution. In this system, the layered extrudate formed Zhiwai the second polyolefin solution layer comprises an extruded and the extruded intermediate layer comprising a first polyolefin solution being constituted. C. A third method of manufacture for the manufacture of a multilayer microporous polyolefin membrane comprises the steps of: (1) combining the first polyolefin composition with a film forming solvent (eg, by melt blending) to Preparing a first polyolefin solution, (2) combining a second polyolefin composition with a second film forming solution to prepare a second polyolefin solution, and (3) extruding the first polyolefin solution Forming at least one first excipient by at least one first mold', and (4) extruding the second polyolefin solution through at least one second mold to form at least one second extrudate, (5) cooling the first and second extrudates to form at least one first gel-like sheet and -42-200920595 at least one second gel-like sheet, (6) pair The first and second gel-like sheets are laminated to form a multi-layered gel-like sheet (7). The multilayer gel-like sheet obtained from the result is at least partially removed. , a gel-like sheet that has been formed to remove the solvent 'to be removed & (8) The gelatinous sheet of the solvent is dried to form a multilayer @# pore film. Optionally, between steps (5) and (6), or between steps (6) and (7), an optional stretching step (9), and optionally a thermal solvent treatment step (1) 0) and so on. After step (8), an optional step (11) of stretching the multilayer microporous membrane, an optional heat treatment step (12), and an optional crosslinking step (13) with free radiation, And optionally a hydrophilic treatment step (14) and the like. The main difference between the third manufacturing method and the second manufacturing method is the order of the lamination and cooling steps. In the second manufacturing method, lamination of the first and second polyolefin solutions is carried out prior to the cooling step. In the third manufacturing process, the first and second polyolefin solutions are cooled prior to the lamination step. Steps (1), (2), (7), and (8) in the third manufacturing method may be combined with steps (1), (2), (5), and (6) in the first manufacturing method described above. )the same. The condition of the step (3) of the second manufacturing method is used for the step (3) of the third manufacturing method in terms of the extrusion of the first polyolefin solution through the first mold. The condition of the third manufacturing method step (4) can be the same as the condition of the second manufacturing method step (3) in order to extrude the second polyolefin solution through the second mold. In a system, either the first or second polyolefin solution is extruded through a third mold. In this manner, the resulting multilayer laminate can have a two layer produced from the first polyolefin solution and a single layer produced from the second polyolefin solution, or vice versa. The step (5) of the third manufacturing method may be the same as the step (4) of the first manufacturing method 'except in the second manufacturing method, the first and second gel-like sheets are respectively formed outer. The step (6) of laminating the first and second gel-like sheets will be described in detail below. The method of lamination is not strictly limited, and a conventional lamination method such as heat-induced layering (Ιιεαί-ί nduced 1 aminati ο nmeth 〇ds ) may be used to laminate the multi-layered gel-like sheet. . Other suitable lamination methods include, for example, heat sealing, impulse-sealing, ultrasonic-bo n d i n g, etc., which may be used singly or in combination. The heat sealing process can be carried out, for example, by one or more pairs of heated rollers, wherein the gel-like sheet is guided through at least one pair of heated rollers. Although there is no strict limit to the heat sealing temperature and pressure, sufficient heating and pressure should be applied for a sufficient period of time to ensure that the gel-like sheets are properly joined to provide a multilayer micro-layer having relatively uniform properties and a low tendency to delamination. Porous membrane. In the unitary system, the heat sealing temperature may be, for example, from about 90 ° C to about 1 35 ° C, or from about 90 ° C to about 1 15 ° C. In a system, the heat sealing pressure can be about 〇. 〇 1 MP a to about -5 0 Μ P a. As in the case of the first and second manufacturing methods, the layer formed by the first and second polyolefin solutions (ie, the layer comprising the first and second microporous layer materials) The thickness ' can be adjusted by adjusting the thickness of the first and second -44-200920595 gel-like sheets and by the amount of stretching (stretching ratio and dry stretching ratio) (when one or more are used) When the stretching step is), it is controlled. Alternatively, the laminating step and the stretching step may be combined by passing the gel-like sheet through a multi-stage heating roller. In a system, the third manufacturing process forms a multilayer polyolefin gel-like sheet having at least three layers. For example, after cooling two extruded first polyolefin solutions and one extruded second polyolefin solution to form a gel-like sheet, the multilayer gel-like sheet can contain extrusion The outer layer of the first polyolefin solution and the intermediate layer comprising the extruded second polyolefin solution are laminated. In another system, after cooling the two extruded second polyolefin solution and an extruded first polyolefin solution to form a gel-like sheet, the 'multilayer gel-like sheet can be combined with An outer layer comprising the extruded second polyolefin solution and an intermediate layer comprising the extruded first polyolefin solution are included. The stretching step (9) and the hot solvent treatment step (1 〇) may be the same as the stretching step (7) and the hot solvent treatment step (8) described in the first preparation method, but the stretching step (9) and the heat The solvent treatment step (丨〇) can be carried out on the first and/or second gel-like sheet. The stretching temperatures of the first and second gel-like sheets are not strictly limited. For example, the stretching temperature of the first gel-like sheet may be, for example, Tm ! + 1 0 〇 C or lower or alternatively about Ted! or higher but lower than Tmi. The stretching temperature of the second gel-like sheet may be, for example, T m 2 + 1 0. (: or lower, or alternatively about Tcd2 or higher but less than about Tm2. -45- 200920595 D. A fourth method of manufacturing the fourth method for producing a multilayer microporous polyolefin film comprises the steps of: (1) forming a first polyolefin composition with a film forming solvent, for example, by melt doping) a polycarbonate melts the second polyolefin composition with a second film forming solvent, a second polyolefin solution, and (3) extruding the first polyolefin solution into at least one first mold, and Forming at least one first extrusion 4) extruding the second polyolefin solution through at least one second to form at least one second extrudate, (5) cooling the first and extrudate to form At least one first gel-like sheet and a second gel-like sheet, (6) removing at least a portion of the first and second membranes from the first and second sheets Form the first and second gel-like flakes that have been dissolved to remove the solvent! The first and second gelatinous sheets of solvent have been dried, one less first polyolefin film and at least one second polyolefin and (8) the first and second porous polyolefins The film is laminated to a multilayer microporous polyolefin film. If necessary, between steps (5) and (6), pull (9), hot solvent treatment step (10), etc., if necessary, between 'and' and (8) 'stretching step (丨丨). , heat treatment 12) and so on. If necessary, after the step (8), the step (13) of pulling the microporous membrane, the heat treatment step (14), the crosslinking step (15) using the shot, the hydrophilic treatment step (〖6), etc. may be performed. Steps (1) and (2) in the four preparation methods may be combined with the following steps (example (2) to prepare a pressure-passing material, (mold, second at least one gel-like agent, shape: 7) Formed into a film to form a stretching step (7 steps (steps (1) and (2) in the manufacturing method of the first-46-200920595 manufacturing method. In the fourth manufacturing method The steps (3), (4) and (5) can be carried out under the same conditions as the steps (3), (4) and (5) in the third method. Steps in the fourth manufacturing method (6) It can be carried out under the same conditions as in the step (5) of the first manufacturing method, except for the portion from which the first and second gel-like sheets are removed to form a solvent. In the fourth manufacturing method, Step (7) can be carried out under the same conditions as step (6) of the first manufacturing method, but in the fourth In the manufacturing method, the first and second solvent-removed gelatinous sheets are separately dried. Step (8) in the fourth manufacturing method may be the same as step (6) of the third manufacturing method. Except under the condition of laminating the first and second polyolefin microporous membranes. The stretching step (9) and the thermal solvent treatment step (10) in the fourth manufacturing method may be carried out in the same manner. The steps (9) and (1) of the three manufacturing methods are carried out under the same conditions. The stretching step (11) and the heat treatment step (12) in the fourth manufacturing method can be carried out in steps with the first manufacturing method ( 9) and (10) are carried out under the same conditions, but in the fourth manufacturing method, the first and second polyolefin microporous membranes are subjected to stretching and/or heat treatment. In the stretching step (11) of the fourth manufacturing method, the stretching temperature of the first polyolefin microporous film may be about Tm i or lower, or alternatively Tcdt to about Tm, and second The stretching temperature of the polyolefin microporous film may be about Tm2 or lower, or alternatively about Tcd2 to about Tm 2 In a system, the heat treatment step (12) -47- 200920595 in the fourth manufacturing method may be HS and/or annealing. For example, in the heat treatment step (12) of the fourth manufacturing method, the first polyolefin The heat setting temperature of the microporous membrane may be from about Td! to about Τπμ, or alternatively about ±5 °C of the dry stretching temperature, or alternatively about ±3 t of the drying temperature. In one system, In the heat treatment step (12) of the fourth manufacturing method, the heat setting temperature of the second microporous film may be from about Tcd2 to about Tm2, or alternatively to a dry stretching temperature of ±5 °C, or alternatively The drying temperature is ±3 °C. When HS is employed, it can be carried out, for example, by a tenter method or a roller method. In a system, in the heat treatment step (12) of the fourth manufacturing method, the annealing temperature of the first microporous membrane may be about Tmi or lower, or alternatively about 60 ° C to about ( Tm ! -1 0 °C ). In a system, in the heat treatment step (12) of the fourth manufacturing method, the annealing temperature of the second microporous film may be about T m 2 or lower, or alternatively about 60 ° C to Approx. (T m 2 -1 0 °C). The fourth step of the step of stretching the multilayer microporous membrane in the fourth manufacturing method, the heat treatment step (14), the crosslinking step using the free radiation (15), and the hydrophilic treatment step (16) The steps (9), (1〇), (11) and (12) of a manufacturing method are the same. [4] Properties of multilayer microporous polyolefin film In a system, the thickness of the multilayer microporous polyolefin film is in the range of from about 3 μηη to about 200 μηη, or from about 5 μm to about 50 μηη. Optionally, the multilayer microporous polyolefin membrane has one or more of the following characteristics. -48- 200920595 A _ Porosity is from about 25% to about 80% When the porosity is less than 25%, the multilayer microporous polyolefin film generally does not exhibit the desired gas permeability for use as a battery separator. When the porosity exceeds 80 ° /. It is more difficult to manufacture a battery separator having the required strength, which increases the possibility of short circuits of the internal electrodes. Β 1 . The gas permeability is about 20 seconds / 1 0 0 c m3 to about 7000 seconds / 1 0 0 c m3 (converted to 値 at a thickness of 20 - μ m) when the permeability of the multilayer microporous polyolefin membrane (such as According to JISP 8 1 1 7), when it is in the range of about 20 seconds / 100 em3 to about 700 seconds / 100 cm3, it is less difficult to form a battery having a desired charge storage capacity and a desired charge and discharge cycle. When the gas permeability is less than about 20 seconds / 1 0 0 c m3, it is more difficult to manufacture a battery having a desired shutdown characteristic, especially when the temperature inside the battery rises. According to JIS P8117, the gas permeability P? measured on the multilayer microporous film having a thickness of ΤΊ can be converted into a gas permeability P2 having a thickness of 20 μm by the equation P2 = ( P , x20 ) / T!. B2. The gas permeability after hot compression is about 100 seconds / 100 cm3 to about 1000 seconds / 100cm3 when in 2. The multilayer microporous membrane of the present invention has a gas permeability (measured according to JIS P8117) of about 1 000 sec / 100 cm 3 or less, such as from about 100 to about 1,000, when it is thermally compressed under a pressure of 2 MP a for 5 minutes. Seconds / 100 cm3. A battery using a membrane has a suitably large capacity and a charge-discharge -49-200920595 electrical cycle. The gas permeability after heat compression is preferably, for example, 950 sec / 100 cm 3 or less. C. Pin puncture strength is about 2,000 mN / 20μιη or more. The pinch strength of the pin (converted to 20μΐ film thickness) means that at a speed of 2 mm / sec, with a ball end surface ( Spherical end surface) (curvature radius: 0. 5 mm) 1 mm diameter needle to puncture the maximum load measured on a multilayer microporous polyolefin membrane. When the multilayer microporous polyolefin film has a pin with a compressive strength of less than 2,000 mN / 20 μm, it will be more difficult to produce a battery having desired mechanical integrity, durability and toughness. The shutdown temperature is about 140 ° C or lower. When the shutdown temperature of the multilayer microporous polyolefin film exceeds 1 40 ° C, it is more difficult to manufacture a battery separator which is required to close the reaction when the battery is overheated. One of the ways of determining the shutdown temperature involves measuring the temperature at which the inflection point is observed near the melting point of the multilayer microporous polyolefin film under the following conditions: · at a speed of 5 ° C / min, 3 mm in the longitudinal direction and transverse direction The 10 mm test piece was heated from room temperature while the test piece was stretched in the longitudinal direction under a load of 2 §. In a system, the shutdown temperature is in the range of about 120-140 °C. This measurement can be performed as follows. Using a thermomechanical analyzer (τ M A / s s 6 〇 〇 〇, purchased from Seiko Instruments, Inc. At a rate of 5 ° C / min, starting from room temperature, the test piece of 10 mm (TD) x 3 mm ( -50- 200920595 MD ) of the multilayer microporous membrane was heated while maintaining a constant load of 2 gf. Stretching the test piece longitudinally 'The temperature at which the length of the sample is observed near the melting point of the test piece is defined as "shutdown temperature" (for example, see Fig. 4). I. The melting temperature is at least about 1. 70 °c in a system 'melting temperature can be from about 170 ° C to about } 0 0. (: range. One of the ways to measure the melting temperature involves measuring 3 mm in the longitudinal direction and lateral direction 1 under the following conditions The temperature at which the 0 mm multilayer microporous polyolefin film test piece was broken by melting: the test piece was heated at a heating rate of 5 ° C /min while the test piece was stretched under a load of 2 g. Battery capacity recovery rate is 70% or higher (anti-attenuation property of lithium secondary battery) When a lithium ion secondary battery including a separator formed of a multilayer microporous membrane is stored at 80 ° C for 30 days, The battery capacity recovery rate [(capacity after storage at high temperature) / (initial capacitance)] xl 〇〇 (%) should be 70% or higher. The battery capacity recovery rate should be 75% or higher. L. The thickness variation rate after hot compression is 20% or less at 90 ° C, 2. The thickness variation after hot compression for 5 minutes under a pressure of 2 MPa is usually 20% or less, preferably preferably less than 10%, per 100% of the thickness before compression. A battery including a membrane separator having a variation rate of 20% or less has a suitably large capacity and a good charge and discharge cycle. -51 - 200920595 [5] Battery separator In a system, the battery separator formed by the multilayer microporous polyolefin film has a thickness ranging from about 3 μm to about 200 μm, or from about 5 μm to about 50 μm. Within the scope. Depending on, for example, the choice of electrolyte, the swelling of the separator may increase the final thickness to more than 200 μm. [6] The battery is used in one system, and the multilayer microporous polyolefin film can be used as a separator for primary and secondary batteries. , for example, a lithium ion battery, a lithium-polymer secondary battery, a nickel-hydrogen secondary battery, a nickel-cadmium secondary battery, a nickel-zinc secondary battery, a silver-zinc secondary battery, and specifically a lithium ion secondary battery. Hereinafter, a lithium ion secondary battery will be described. A lithium secondary battery includes a cathode, an anode, and a separator between the anode and the cathode. The separator usually contains an electrolytic solution (electrolyte). The structure of the electrode is not critical and a conventional electrode structure can be used. The electrode structure may be 'for example, a button type (in which the disk-shaped cathode and the anode are opposite); a stacked type (where the planar sheet cathode and the anode are alternately laminated with at least one separator between the anode and the cathode) : and ring type (where the strip cathode and anode are wound together), and so on. The cathode usually comprises a current collector and a cathode active material layer capable of absorbing and releasing lithium ions (which is formed on the current collector). The cathode active material may be, for example, an inorganic compound such as a transition metal oxide - 52 - 200920595, a composite oxide of lithium and a transition metal (lithium composite oxide), a transition metal sulfide, or the like. The transition metal may be, for example, V, Mn, Fe, Co, Ni, or the like. In the system, the lithium composite oxide may be lithium nickelate, lithium cobaltate, lithium manganate, a layered lithium composite oxide based on a-NaFeO 2 or the like. The anode typically includes a current collector and a negative electrode active material layer formed on the current collector. The negative electrode active material may be, for example, a carbon substance such as natural graphite, artificial graphite, coke, carbon black or the like. The electrolytic solution can be obtained by dissolving a lithium salt in an organic solvent. There are no strict restrictions on the choice of solvent and/or lithium salt and conventional solvents and salts can be employed. The lithium salt may be, for example, LiC104, LiPF6, LiAsF6, LiSbF6, LiBF4, LiCF3S03, LiN(CF3S02)2, LiC(CF3S02)3, Li2B10Cl10, LiN(C2F5S02)2, LiPF4(CF3)2, LiPF3(C2F5) 3. Lower aliphatic aliphatic carboxylate of lithium, LiAlCl4, and the like. Lithium salts can be used singly or in combination. The organic solvent may be an organic solvent having a relatively high boiling point (compared to the shutdown temperature of the battery) and a high dielectric constant. Suitable organic solvents include: ethylene carbonate 'propylene carbonate, ethyl methyl carbonate, r-butyrolactone, etc.; organic solvents having a low boiling point and low viscosity, such as tetrahydrofuran, 2-methyltetrahydrofuran, diethyl Oxyethane, dioxane, dimethyl carbonate, diethyl carbonate, and the like, including mixtures thereof. Since organic solvents which generally have a high dielectric constant often have a high viscosity and vice versa, a mixture of high and low viscosity solvents can be used. When the battery is assembled, the separator is usually impregnated with an electrolytic solution to provide ion permeability to the separator (multilayer microporous membrane). There is no strict restriction on the choice of -53- 200920595 for the soaking method' and the conventional soaking method can be used. For example, the impregnation treatment can be carried out by immersing the multilayer microporous membrane in an electrolytic solution at room temperature. There is no strict limitation on the method of selecting a battery for combination, and a conventional battery combination method can be employed. For example, when a cylindrical battery is combined, a cathode sheet, a separator formed of a multilayer microporous film, and an anode sheet are sequentially laminated, and the resultant laminate is wound into a ring electrode combination. It may be necessary to have a second baffle to prevent short circuits of the windings. As a result, the obtained electrode combination can be embedded in the battery, and then permeated with the aforementioned electrolytic solution, and a battery cover equipped with a safety valve as a cathode terminal is plugged to the battery via a gasket to manufacture a battery. [Embodiment] [ 7] Examples The present invention will be described in more detail with reference to the following non-limiting examples. Example 1 (1) Preparation of First Polyolefin Solution A first polyolefin composition was prepared by dry blending, which contained (a) 82% PE1' having a weight average molecular weight of 3_0x10 and a molecular weight distribution of 8 . 6, (b) 8 % PE2 having a weight average molecular weight of 2.0 χ 106 and a molecular weight distribution of 8, (c) 10% of the first polyacrylic resin - 54 - 200920595 having a weight average molecular weight of 1.40 χ 106, heat of fusion Iii. 6 J/g, a molecular weight of 1. 8 χ 1 〇 6 or more and the part is 25.3%, and the molecular weight distribution is 2 · 6 (the percentage is based on the weight of the first polyolefin composition). The polyethylene resin in the composition had a melting point of 135 t and a crystal dispersion temperature of 10 °C. 25 parts by weight of the resulting polyolefin composition was charged into a strongly blended twin roll extruder (having an inner diameter of 58 mm and an L/D of 42), and 75 parts by mass via a side feeder Liquid paraffin (50 cst at 40 ° C) was supplied to the twin roll extruder. Melt blending was carried out at 210 ° C and 200 rpm to prepare a first polyolefin solution. (2) Preparation of second polyolefin solution A second polyolefin solution was prepared in the same manner as described above except for the following. A second polyolefin composition comprising: (a) 4 7 % P EI having a weight average molecular weight of 3.0 χ 105 and a molecular weight distribution of 8. 6, and (b) 3% PE2, which has a weight average molecular weight of 2. OxlO6 and molecular weight distribution 8, and (c) 50% of the second polypropylene resin having a weight average molecular weight of 1. 40 X106, heat of fusion 111. 6 J/g, having a molecular weight of 1.8 χ 106 or greater and the portion accounting for 25. 3% and molecular weight distribution 2. 6 (the percentage is based on the weight of the second polyolefin composition). The polyethylene resin in the composition had a melting point of 135 ° C and a crystal dispersion temperature of l〇〇t. The second polyolefin composition obtained as a result of 35 parts by weight was placed in a strongly blended twin roll extruder (inner diameter 58 mm and L/D 42) and fed by side-55-200920595 side 65 parts by mass of liquid paraffin (50 at 40 ° C) was supplied to the twin roll extruder. The melt blending was carried out at 210 ° C and 200 rpm to prepare a second polyolefin solution. (3) The film was produced by their respective twin roll extruders, and the first and second olefin solutions were supplied to a three-layer extruded T-die, and the thickness of the extruded layer was 42 from the die. . 5 / 10/ 42. An extrudate (also referred to as a laminate) of the first polyolefin solution layer/second polyolefin solution layer/first polyolefin solution layer. When the extrudate was passed through a cooling roller controlled at 20 ° C, it was cooled to form a three-layer gel-like sheet, which was stretched by a tenter type machine at 1 18 ° C. At the same time, the machine (longitudinal) and the transverse side are simultaneously biaxially stretched and stretched to a magnification of 5 times. The over-stretched three-layer gel-like sheet was fixed to an aluminum frame of 20 cm x 20 cm, and it was immersed and controlled at 25. (: in a dichloromethane bath, at 100 rpm (for 3 minutes), remove the liquid paraffin, and dry at room temperature by air flow. By batch-stretchi machine, The dried film was stretched to 1. in the transverse direction at i25t. 4 times magnification. The restretched film was still fixed on a batch stretching machine at 125 ° C and heat-set for 10 minutes to prepare a three-layer microporous film. Example 2 Example 1 was repeated, but the dried three-layer film was not stretched. < C St row is aggregated into the same) to the upper vibration by ng ( 造 -56 - 200920595 Example 3 is repeated Example 1, but the first and second microporous polyolefin membranes are based on the first micro The order of the porous membrane/second microporous membrane/first microporous membrane was laminated at a layer thickness ratio of 25 / 5 0 / 25. Example 4 Example 1 was repeated, but the first polyolefin composition The first polypropylene resin in the article had a weight average molecular weight of 6.6 x 1 〇 5, a heat of fusion of 103.3 J / g, a portion having a molecular weight of 1.8 x 106 or more and a molecular weight distribution of the portion of 8.2% and 11. Example 5 Example 1 was repeated, however, the first polypropylene resin in the first polyolefin composition had a weight average molecular weight of 6.8 x 105, a heat of fusion of 94.6 J/g, and a molecular weight of 1.8 x 106 or more. The large portion and this portion accounted for a molecular weight distribution of 4.7 %, and 5.9. Example 6 Example 1 was repeated, but the first polypropylene resin in the first polyolefin composition had a weight average of 3.00 χ 105 Molecular weight, heat of fusion of 88.9 J/g, molecular weight of 1.8 χ 106 or Large part and this part accounts for %, and molecular weight distribution of 4. 9 -57- 200920595 Example 7 Example 1 is repeated, but the second polypropylene resin in the second polyolefin composition has 〇· The weight average molecular weight of 9〇χ1〇6, the heat of fusion of 109.7 J/g, the portion having a molecular weight of 1.8×10 6 or more and the portion accounting for 10.8%, and the molecular weight distribution of 2.4. Example 8 Repeated Examples 1, but the second polypropylene resin in the second polyolefin composition has a weight average molecular weight of 2.69 χ 1 〇 6, a heat of fusion of 99.9 J / g, a molecular weight of 1.8 χ 106 or more and the The fractions accounted for a molecular weight distribution of 57.2% and 3·8. Example 9 Example 1 was repeated, but the first polyolefin composition in the first polyolefin solution contained 90% PE 1 and 1%% first. Polypropylene resin (percentage based on the weight of the first polyolefin composition). In this first polyolefin composition, there is no second polyethylene resin. Example 1 〇 Repeat Example 1, but second Second polyolefin composition in a polyolefin solution The composition comprises 50% PE 1 and 50% of the first polypropylene resin (the percentage is based on the weight of the first polyolefin composition). In this second polyolefin composition, there is no second polyethylene resin. -58- 200920595 Comparative Example 1 Example 1 was repeated, but the first polyolefin-soluble olefin composition contained 82% of the first polyethylene resin as a vinyl resin, and the first polypropylene resin was not added (a hundred polyolefins) The weight of the composition). Comparative Example 2 Example 1 was repeated except for the first polyolefin dissolved hydrocarbon composition. No first polyolefin composition Comparative Example 3 The comparative example 1 was repeated, but the first polyene and one polypropylene resin had a heat of 6.8 g of a weight average of 6.8 g, and a molecular weight of 1.8 x 106 or more. a molecular weight distribution of 7% and 5.9, and the second second polypropylene resin has a heat of fusion of 6.8 χ 105 and a weight of 94.6 J / g, a molecular weight of ΐ·8χ106 or a fraction of 4 -7 %, and 5.9. The molecular weight distribution. Comparative Example 4 Example 1 was repeated, but the first polyolefin group polypropylene resin had a heat of fusion of a weight average of 1.56 x 106, a molecular weight of χ3 5 _4% of 1.8 χ 106 or more, and a molecular weight of 3 2 . Distribution 'and the first poly and 18% second fraction in the second liquid is based on the amount of the first amount in the first polyhydrocarbon composition of the first liquid, 94·6 J / part and the part The amount of the average molecular weight in the polyolefin composition, the larger portion and the first sub-amount in the product, 78.4 J / g minutes and the portion of the polyolefin composition -59-200920595 table a polypropylene resin It has a weight average molecular weight of 1.56 χ 1 〇 6, a heat of fusion of 78.4 J / g, a molecular weight of ι 8 χ 1 〇 6 or more and this part accounts for 35.4 ° /. And the molecular weight distribution of 3.2. Comparative Example 5 Comparative Example 1 was repeated except for the second polyolefin composition in the second polyolefin solution. There is no second polyolefin composition. Properties The properties of the multilayer microporous membranes of Examples 1 - 6 and Comparative Examples 1 - 8 were measured by the following methods. The results are shown in Tables 1 and 2. (1) Average thickness (μπι) The thickness of each microporous film was measured by a contact thickness meter on a film of 10 cm x 10 cm area at intervals of 10 mm, and averaged. The thickness gauge used was a standard deviation (μιη) of Litematic (2) thickness manufactured by Mitsutoyo Corporation. The thickness of each microporous membrane was measured as described above. Based on the thickness data, the standard deviation of the thickness is calculated. -60- 200920595 The air permeability P2 measured by the microporous film having a thickness of 1 μm and a gas permeability P1 of 20 μm. (4) Porosity (%) was measured by a gravimetric method using the following formula: porosity. /. =100>< ( w2_ wl ) / w2, where "wl" is the actual weight of the film, and 2, is the assumed weight of 1% by weight of the polyethylene. (5) Pin pressure resistance (mN / 20μιη) When the speed is 2 mm / sec, a needle having a diameter of 1 mm having a spherical end surface (curvature radius: 0.5 mm) is used to puncture each When a microporous membrane having a thickness of T! is used, the maximum load is measured. The maximum load measured is converted into the maximum load L2 at a thickness of 20 μm by the equation L2 = ( LlX20 ) / Ti, and is used as the pin compressive strength. (6) Thickness variation rate after heat compression (%) Place the microporous membrane sample between a pair of highly flat sheets' and use a press at a pressure of 2.2 MPa (22 kgf / cm2) at 90 °C The lower portion was subjected to thermal compression for 5 minutes, and the average thickness was measured in the same manner as described above. The thickness variation rate is calculated by the equation: (average thickness after compression - average thickness before compression) / (average thickness before compression) χΐ〇〇 ', which can be expressed as absolute 値. -61 - 200920595 (7) Air permeability after hot compression (sec/ wocn^) Under the above conditions, each of the multilayer microporous membranes having a thickness of Τ1 is thermally compressed, and according to JIS Ρ 8 1 1 7, air permeability ρ !Measurement (8) Absorption rate of electrolytic solution Using a dynamic surface tension measuring device (DCAT21, equipped with a high-precision electronic balance, available from Eiko Instruments Co., Ltd.), the multilayer microporous membrane sample was immersed Maintain the electrolytic solution at 18 °C (electrolyte: 1 mol / L LiPF6 'solvent: 3/7 by volume of ethylene carbonate / dimethyl carbonate) by the equation: [weight increase of microporous membrane (g) The weight (g) of the microporous membrane before absorption was measured to determine the absorption rate of the electrolytic solution. The absorption rate of the electrolytic solution is expressed in terms of relative enthalpy, and it is assumed that the absorption rate of the electrolytic solution of the microporous membrane of Comparative Example 5 is 1. (9) Closing temperature (t) The closing temperature is measured as follows: A triangular sample of 3 mm X 50 mm is cut from the microporous membrane so that the longitudinal direction of the sample is in line with the transverse direction of the microporous membrane. And fixed it to a thermomechanical analyzer (TMA / SS6000, available from Seiko Instruments, Inc.) with a chuck distance of 10 mm. A load of 19.6 mN was applied to the lower end of the sample, and the temperature was raised at a rate of 5 °C / minute to measure the change in size. The temperature at which the inflection point is observed near the melting point is defined as the shutdown temperature. -62- 200920595 (10) Melting temperature (°C) The melting temperature was measured using a thermomechanical analyzer (TMA / SS6〇〇〇' available from Seiko Instruments, Inc.) in the same manner as the above-mentioned shutdown temperature. The melting temperature is the temperature at which the film breaks. (11) Capacitance recovery rate The capacity recovery rate of a lithium ion battery including a multilayer microporous membrane as a separator was measured as follows: First, the measurement was performed by a charge/discharge tester before storage at a high temperature. The discharge amount (starting capacity) of a lithium ion battery. After storage at 80 ° C for 30 days, the discharge amount was measured again by the same method, and the capacity after high-temperature storage was obtained. The battery's capacity recovery rate (%) is determined by the following equation: capacitance recovery rate (%) = [(capacity after high temperature storage) / (initial capacitance)] χ 100 -63- 200920595 Table 1 Number implementation Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Resin composition First polyolefin PEI Mw 3.0 x 10s 3.0 xlO5 3.0 x 10s 3.0 xlO5 3.0 x10s 3.0 xlO5 Mw/Mn 8.6 8.6 8.6 8.6 8.6 8.6 mass% 82 82 82 82 82 82 PE2 Mw 2.0 xlO6 2.0 xlO6 2.0 χ 106 2.0 χΙΟ6 2.0 χ 106 2.0 χ 106 Mw/Mn 8 8 8 8 8 8 Mass % 8 8 8 8 8 8 PP Mw 1.40 x 106 1.40 χ ΙΟ6 1.40 χ 1〇6 6.6 χΙΟ5 6.8 xlO5 3.0 xlO5 Mw/Mn 2.6 2.6 2.6 11 5.9 4.9 HMWF(,) 25.3 25.3 25.3 8.2 4.7 0 Heat of fusion (J/g) 111.6 111.6 111.6 103.3 94.6 88.9 mass% 10 10 10 10 10 10 Concentration mass % of olefin composition 25 25 25 25 25 25 Second polyolefin PB1 Mw 3.0 χ 105 3.0 χΙΟ5 3.0 χ ΙΟ5 3.0 χ ΙΟ5 3.0 χ ΙΟ5 3.0 x10s Mw/Mn 8.6 8.6 8.6 8.6 8.6 8.6 mass% 47 47 47 47 47 47 PE2 Mw 2.0 xlO6 2.0 χΙΟ6 2.0 χΙΟ6 2 .0 χΙΟ6 2.0 χ ΙΟ6 2.0 xlO6 Mw/Mn 8 8 8 8 8 8 mass % 3 3 3 3 3 3 PP Mw 1.40 xlO6 1.40 χ ΙΟ6 1.40 χ ΙΟ6 1.40 χ ΙΟ6 1.40 χΙΟ6 1.40 χ ΙΟ6 Mw/Mn 2.6 2.6 2.6 2 ,6 2.6 2.6 HMWF 0) 25.3 25,3 25.3 25.3 25.3 25.3 Heat of fusion (J/g) 111.6 111.6 111.6 111.6 111.6 111.6% by mass 50 50 50 50 50 50 Concentration mass% of polyolefin composition 35 35 35 35 35 35 Manufacturing condition Extrusion layer structure (2) (1)/(11)/(1) (1)/(11)/(1) (1)/(11)/(1) (1)/(11)/(1) (1)/(ny (i) (1)/(11)/(1) Layer thickness ratio 40/20/40 40/20/40 25/50/25 40/20/40 40/20/40 40/20/40 gelatinous Stretching temperature of sheet (°C) n) 118 118 118 118 118 118 Magnification (MDxTD) 3 5x5 5x5 5x5 5x5 5x5 5x5 Stretching temperature of dry film (eC) 125 - 125 125 125 125 magnification (TD) 1.4 * 1.4 1.4 1.4 1.4 Heat setting temperature) 125 125 125 125 125 125 Time (minutes) 10 10 10 10 10 10 Average thickness of properties (#m) 19.9 21.0 20.0 20.5 20.4 20.4 Standard deviation of thickness (Am) 0.61 0.66 0.59 2.11 2.49 3.58 Air permeability (sec/1 00cm3/2(Vm) 220 315 502 203 215 194 Porosity % 51.9 49.9 48.2 53.2 53.4 52.6 Housing strength (mN/20/m) 3150 3010 2930 3050 3000 2950 Thickness variation rate after hot compression % 10 -10 - 13 -11 -9 -10 •12 Air permeability after hot compression 435 630 980 410 430 400 Absorption rate of electrolytic solution 3.4 2.1 3.6 2.2 2.1 1.9 Switching temperature π 135 135 135 135 135 135 Melting temperature 11 178 178 ISO 177 \V 176 Capacitance recovery rate % 78 77 78 77 76 70 -64- 200920595 Table 1 (continued) No. Example 7 Example 8 Example 9 Example 10 Resin composition First polyolefin PEI Mw 3.0 x10s 3.0 xlO5 3.0 x10s 3.0 X10s Mw/Mn 8.6 8.6 8.6 8.6 mass% 82 82 90 82 PE2 Mw 2.0 x!06 2.0 xlO6 - 2.0 xlO6 Mw/Mn 8 8 - δ mass% 8 8 - 8 pp Mw 1.40 xlO6 1.40 χ10δ 1.40 xlO6 1.40 xlO6 Mw/ Mn 2.6 2.6 2.6 2.6 HMWF (1) 25.3 25.3 25.3 25.3 Heat of fusion (1⁄4) 111.6 111.6 111.6 111.6% by mass 10 10 10 10 Concentration mass% of polyolefin composition 25 25 25 25 Second polyolefin PEI Mw 3.0 χ 105 3.0 χ Ι Ο5 3.0 xlO5 3.0 χΙΟ5 Mw/Mn 8.6 8.6 8.6 8.6 mass% 47 47 47 50 PE2 Mw 2.0 xlO6 2.0 χΙΟ6 2.0 χ ΙΟ6 - Mw/Mn 8 8 8 - 童童% 3 3 3 - PP Mw 0.90 χ ΙΟ6 2.69 χ ΙΟ6 1.40 χ ΙΟ6 1.40 χ ΙΟ6 Mw/Mn 2.4 3.8 2.6 HMWF (1) 10.8 57.2 25.3 25.3 Heat of fusion (J/g) 109.7 99.9 111.6 111.6% by mass 50 50 50 50 Concentration mass% of polyolefin composition 35 35 35 35 Manufacturing conditions extrudate n, layer structure (2) (Ι) / (talk) (iy (ny (i) mmi) (1) / (11) / (1) layer thickness ratio 40/20/40 40/20/40 40/20/40 40/20/40 Stretching of gelatinous sheet 118 118 118 118 Temperature (C) Magnification (MDxTD: ^ 5x5 5x5 5x5 5x5 Stretching temperature of dry film (t) 125 125 125 125 magnification (TO) 1.4 1.4 1.4 1.4 Thermal drawing treatment 125 125 125 125 Temperature (Ο Time (minutes) 10 10 10 10 Average thickness of properties (//m) 19.3 19.9 19.5 20.2 Standard deviation of thickness (private m) 0.61 0.60 0.53 0.60 Ventilation Rate (sec/100cm3/2(Vm) 188 330 231 208 Porosity % 53.1 48.2 52.4 52.1 Foot compressive strength (mN_m) 3100 3300 3210 3220 Thickness variation rate after hot compression % -8 -7 •10 .12 Air permeability after heat shrinkage 389 660 480 440 Electrolytic solution absorption speed 3.5 2.9 3.5 3.3 Closing temperature t 135 135 135 135 Melting temperature *c 175 176 177 178 Capacity recovery rate % 78 77 81 80 -65- 200920595 Table 2 No. Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Resin composition聚烯烃One polyolefin PEI Mw Mw/Mn Mass % PE2 Mw Mw/Mn Mass % PP Mw Mw/Mn HMWF (1) Heat of fusion (J/g) Mass % Concentration mass % of polyolefin composition 3.0 X 105 8.6 82 2.0 xlO6 8 18 25 - 3.0 xlO5 8.6 82 2.0 xlO6 8 8 6.8 χ ΙΟ5 5.9 8.4 94.6 10 25 3.0 xlO5 8.6 82 2.0 χΙΟ6 8 8 1.56 χ ΙΟ6 3.2 1.2 78.4 10 25 3.0 xlO5' 8.6 82 2.0 χΙΟ6 8 18 25 Second polyolefin PHI Mw Mw/Mn Mass % PE2 Mw Mw/Mn Mass % PP Mw Mw/Mn HMWF(l) Heat of fusion (J/g) Mass % Concentration mass % of polyolefin composition 3.0 xlO5 8.6 47 2.0 xlO6 δ 3 1.40 χ 106 2.6 25.3 111.6. 50 35 3.0 χ 105 8.6 47 2. 0 xlO6 8 3 1.40 χ 106 2.6 25.3 111.6 50 35 3.0 χΙΟ5 8.6 47 2.0 χΙΟ6 8 3 6.8 χ ΙΟ5 5.9 8.4 94.6 50 35 3.0 χΙΟ5 8.6 47 2.0 χΙΟ6 8 3 1,56 χΙΟ6 3.2 1.2 78.4 50 35 - Manufacturing conditions extrusion (7) Layer structure (2) Layer thickness ratio (1)/(11)/(1) 40/20/40 (II) 100 (1)/(11)/(1) 40/20/40 (1)/(11 )/(1) 40/20/40 (I) 100 Stretching temperature of gelatinous sheet m (3) Magnification (MDxTD) W 118 5x5 118 5x5 118 5x5 118 5x5 115 5x5 Stretching temperature of dry film (t) Magnification (TD) 125 1.4 125 1.4 125 1.4 125 1.4 125 1.4 Heat setting temperature CC) Time (minutes) 125 10 125 10 125 10 125 10 127 10 Average thickness of properties (/m) 20.3 20.2 19.1 19.6 20.3 Standard deviation of thickness (;/m) 0.39 0.54 2.33 1.13 0.41 Air permeability (sec/100cm3/2〇Mm) 360 430 100 690 370 Porosity % 47.8 45.2 58.6 48.2 39 Pin resistance _/20/m) 3210 3420 1710 1280 4410 Thickness variation rate after hot compression % -20 -11 -17 -20 -21 Air permeability after hot compression 880 820 210 1650 830 Absorption speed of electrolytic solution 1.2 2.4 2.7 1.6 1 Shutdown temperature It 135 135 135 135 135 Melting temperature It 177 179 162 160 148 Capacitance recovery rate 67 67 73. 73 65 -66 - 200920595 (1) HMWF means the molecular weight is i.8xl〇6 or more (% by mass) Molecular weight fraction. (2) (I) shows the first polyolefin solution, and (II) shows the second polyolefin solution. (3) (MDxTD) shows the magnification in the longitudinal direction (MD) and the transverse direction (TD). It can be noted from Table 1 that the multilayer microporous membrane of the present invention has balanced properties including standard deviation of thickness, gas permeability, pin pressure resistance, shutdown temperature, and melting temperature, as well as excellent absorption of electrolytic solution. The thickness and the gas permeability after heat compression are small. The lithium ion secondary battery comprising the multilayer microporous membrane of the present invention has a capacity recovery ratio of 70% or more, indicating that it has a desired high temperature anti-attenuation property. On the other hand, the microporous membrane product of the comparative example exhibited a poor balance of properties. The multilayer microporous membrane of the present invention has a balanced property and, if it is a multilayer microporous membrane as a battery separator, provides a battery having excellent safety, heat resistance, and anti-attenuation properties and productivity. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a diagram showing an example of a typical D S C curve. Figure 2 is a diagram showing another example of a typical D S C curve. Fig. 3 is a view showing the same GPC curve as in Fig. 2, in which a portion having a high molecular weight is obliquely lined. -67- 200920595 Figure 4 shows a diagram of an example of a typical TMA measurement with the off temperature shown by an arrow. -68-