200809022 (1) 九、發明說明 【發明所屬之技術領域】 本發明係關於一種模數低、且熱黏著時具有自拉伸 性、作爲熱黏著不織布時呈現柔軟觸感之自拉伸性熱黏著 性複合纖維與其製造方法。 【先前技術】 通常，熱黏著性樹脂成分作爲鞘、代表纖維形成性樹 脂成分作爲芯之芯鞘型熱黏著複合纖維之熱黏著性複合纖 維，係藉由梳棉機法或氣流法（air-laid)、濕式抄紙法等， 形成纖維棉網之後，經由熱風乾燥機處理或熱輥處理熔化 熱黏著性樹脂成分，使形成纖維間結合作爲不織布而被使 用。即，由於不使用有機溶劑作爲溶劑之黏著劑，以有機 溶劑開始之有害物質之排出量少一點爲優點而言可以完 成。又，由於生產速度提高及伴隨其之成本降低的優點亦 大，故廣泛逐漸被使用於纖維緩衝墊（硬綿）、床墊等的 纖維結構體或不織布用途上。 其中，也有就代表紙尿布或衛生綿等衛生材料之熱黏 著性不織布而言，由於不織布有直接接觸肌膚，故謀求不 織布具有像布一樣的柔軟性或懸垂性，且具有非紙質感 (paper-like)、適度的蓬鬆性。因此具有那樣特性的不織 布係從以前開始就持續被硏討著。 將自熱黏著性纖維得到的棉網進行熱黏著的方法之一 中，有藉由壓紋輥等熱壓黏棉網的一部份軟化或熔融接合 -4- 200809022 之熱輥法。此方法係在熱壓黏領域與非熱壓黏領域的交界 等不織布變容易彎折，所得之不織布係具懸垂性優異。但 是，爲將熱壓黏領域的纖維經壓黏被扁平化，而被壓黏的 部分係變硬、失去不織布的蓬鬆性，得到的不織布僅止於 有紙質感的觸感而已。 一方面’作爲將自熱黏著性纖維得到的棉網進行熱黏 著之方法的其它方法，有對棉網整體吹熱風軟化纖維的交 點或熔融的熱風法。此方法，係因留有棉網之容積於某程 度之狀態讓熱風通過，故所得之不織布具有蓬鬆性，其所 得之不織布不會有部分的變硬之領域，表面的接觸係變光 滑者。一方面，彎曲不織布時，不織布易出現不規則的折 痕，而成懸垂性差之不織布。 作爲其解決方法，以下所示手法揭示於專利文獻1 中。即藉由高速紡絲法，將熱黏著性樹脂成分的取向指數 作25%以下，纖維形成性樹脂成分的取向指數作40%以 上，可得黏著強度強、且低溫下熔接、並且熱收縮率小的 熱黏著性複合纖維。因其熱黏著性複合纖維與非熱黏著性 纖維的混綿棉網藉由熱風法使其黏著，爲製造有懸垂性與 蓬鬆性，且具有充分的不織布強度之不織布的技術。然 而，高速紡絲法，就現在的短纖維製造製程係步驟安定性 尙不足、收率差。進而，考量所得之短纖維的性能’成本 性能（cost performance)係不足，經高速紡絲法之短纖維的 商業生產係可說尙有許多困難的課題。且，熱黏著性複合 纖維在單獨下形成熱黏著不織布時，由於不織布中的黏著1 -5- (3) (3)200809022 交點數變多，難於得到具柔軟觸感的不織布，而有得懸垂 性差之不織布的傾向。因此，通常以減少黏著交點數目的 而混綿非熱黏著性纖維製造不織布，但此時係因不織布中 的黏著交點數變少，故有不織布強度下降之傾向。因而， 不織布強度與柔軟觸感係不一定足夠的水準。 進而，纖維形成性樹脂成分爲構成芯成分之複合纖 維，表示其芯成分爲聚對苯二甲酸乙二醇酯（以下，記 PET)之熱黏著性複合纖維的實施例，於專利文獻1中並無 揭示。熱黏著性複合纖維的芯成分作爲PET，係比較熱黏 著性複合纖維的芯成分爲聚丙烯（以下，記PP)時，因爲芯 成分的熔點可以比鞘成分的熔點相當高，可以更進一步提 昇所得不織布的熱黏著強度。又，如此之芯成分作爲PET 之複合纖維係比較有高剛性，故可得具有更蓬鬆的不織布 之可能。但是，使用如專利文獻1中所述的低倍率延伸處 理過之複合纖維或僅未延伸的複合纖維而製造不織布，亦 由於使用之複合纖維的芯成分之取向結晶性不足，熱收縮 係變大。進而，適當使用如專利文獻1中所述之高速紡 絲、以芯成分作爲PET之複合纖維，爲防止芯成分急速 固化，紡絲時，對照複合纖維的芯成分之熔融溫度，不得 不提高複合纖維的鞘成分之熔融溫度。如此，則構成鞘成 分之聚合物的劣化及紡絲牽伸大，故有紡絲時非常容易發 生斷絲的課題。 (專利文獻1)日本特開2005-3 5083 6號公報 200809022 (4) 【發明內容】 發明所欲解決之課題 本發明爲鑒於上述以往技術，其目的係在於提供一種 聚對苯二甲酸乙二醇酯做爲纖維形成性樹脂成分，可製造 具有黏著強度高、蓬鬆且良好的懸垂性之不織布或纖維結 構體之低模數的自拉伸性熱黏著性複合纖維。 課題所欲解決之手段 本發明人等係爲解決上述課題反覆專心檢討之結果， 發現作爲熱黏著性樹脂成分，使用具有比P E T低20°(：以 上的熔點之結晶性熱可塑性樹脂，以1 300m/min以下的紡 絲速度所牽引之未延伸絲，進行非加熱或於冷媒中，一邊 冷卻一邊冷延伸1.05〜1.30倍之後，比熱黏著性樹脂成分 之玻璃轉移溫度與纖維形成性樹脂成分之玻璃轉移溫度之 雙方，藉由在高1 〇°C以上的溫度下使弛緩熱收縮，遂至發 明滿足高黏著強度、充分蓬鬆性及懸垂性，以PET做纖 維形成性樹脂成分之低模數的自拉伸性熱黏著性複合纖 維。 更具體而言，上述課題係可藉由爲纖維形成性樹脂成 分及熱黏著性樹脂成分所成之複合纖維，其特徵係纖維形 成性樹脂成分爲聚對苯二甲酸乙二醇酯所成，熱黏著性樹 脂成分係具有比纖維形成性樹脂成分低2 0 °C以上熔點之結 晶性熱可塑性樹脂所成，斷裂伸度爲130〜600%、100%拉 伸應力爲0.3〜l.OcN/dtex、120°C乾熱收縮率爲比-1.0%小 200809022 (5) 之自拉伸性熱黏著性複合纖維的發明解決。又，上述課 題，係可藉由以1 3 00m/min以下之紡絲速度所牽引之複合 纖維的未延伸絲冷延伸1.05〜1.30倍之後，以比熱黏著性 樹脂成分之玻璃轉移溫度與纖維形成性樹脂成分之玻璃轉 移溫度之雙方，高10 °C以上的溫度下使弛緩熱收縮爲特徵 之熱黏著性複合纖維的製造方法解決。 發明效果 使用本發明之低模數的自拉伸性熱黏著性複合纖維， 製造出的不織布，係不進行經混綿非熱黏著性纖維之黏著 交點的減少操作，也呈現熱黏著性複合纖維本身的低模數 特性與依據自拉伸性之柔軟的觸感。且同時，其不織布係 可保有熱黏著性複合纖維單獨所成之熱黏著不織布特有的 高黏著強度。 實施發明之最佳形態 以上就本發明之實施形態詳細說明。首先，本發明爲 纖維形成性樹脂成分及熱黏著性樹脂成分所成之複合纖 維。更詳細說明，係其纖維形成性樹脂成分作爲PET、具 有比PET低20°C以上熔點之結晶性熱可塑性樹脂作爲其 熱黏著性樹脂成分之低模數的自拉伸性熱黏著性複合纖 維。其中，PET與熱黏著性樹脂成分的熔點差爲低於 2(TC，則熔化熱黏著性樹脂成分使其黏著之步驟中，纖維 形成性樹脂成分亦跟隨溶解，無法製造黏著強度高的不織 -8 - (6) (6)200809022 布或纖維結構體，故不佳。熔點差的範圍係以20〜180°C爲 較佳的範圍。 此複合纖維係使用周知的複合纖維之熔融方法或抽絲 頭，紡絲速度以1〇〇〜1 3 00m/min得未延伸絲，其後冷延伸 1.05〜1.30倍，進而PET的玻璃轉移溫度（以下，記T g ) 與比構成熱黏著性樹脂成分之熱可塑性結晶性樹脂之Tg 的雙方高1 〇°C以上、比熱黏著性樹脂成分之熔點低1 0°C 以下的溫度，較佳係比彼等之Tg高2 0°C以上、比熱黏著 性樹脂成分之熔點低20 °C以下的溫度下，可藉由弛緩熱收 縮處理製得。具體而言，比爲PET之Tg與熱黏著性樹脂 成分之熱可塑性結晶性樹脂之Tg的雙方高的溫度，係於 多數場合中變成比PET之丁§(約70它）高的溫度。因此， 8 0°C以上、較佳爲90 °C以上的溫度下，進行弛緩熱收縮處 理爲佳。更佳之溫度爲100 °C以上。此弛緩熱收縮處理時 的溫度，係可在熱風中或溫水中進行。於本發明中，構成 熱黏著性樹脂成分之結晶性熱可塑性樹脂之熔點，如同上 述因比PET之熔點低20 °C以上，故構成熱黏著性樹脂成 分之熱可塑性結晶性樹脂之Tg係比PET之Tg低的爲 多。驰緩熱收縮處理的溫度比此溫度範圍低，則複合纖維 的熱黏著時之收縮率變大而不佳。驰緩熱收縮處理的溫度 比此溫度範圍太過於高時，則熱黏著性樹脂成分之樹脂軟 化、可能會擬似膠著。弛緩熱收縮處理，係可爲將延伸後 絲束使不帶有張力的狀態下，藉由通過熱風中之方法，亦 可於溫水中沒有張力般地以〇·5〜0.85倍使超餵之方法。 200809022 藉由上述之弛緩熱收縮處理，實施低倍率延伸之纖維 係藉由永久定型，一邊向纖維軸方向收縮成形成具有自纖 維軸方向朝無規則的方向傾斜之結晶軸之結晶。進而其纖 維藉由施加溫度，其結晶之結晶尺寸變大、相近的存在之 結晶成彼此接觸之狀態，亦更使結晶尺寸變大。如此，產 生看起來像纖維伸長了的現象。此現象稱爲自拉伸性，此 自拉伸性於本發明之複合纖維中呈現。 φ 此現象於紡絲速度2000m/min以上之高速紡絲，係成 更爲顯著之現象。依據本發明人之硏討，紡絲速度在 1 3 00m/min以下所得的未延伸絲之情形，僅少數之倍率下 實施延伸，其後藉由進行驰緩熱收縮之方法，發現自拉伸 率可以更大，遂完成本發明。例如芯成分爲PET(固有黏 度：IV = 0.64dL/g)、鞘成分爲高密度聚乙烯（MER = 20g/10 min)之芯鞘型複合纖維於紡絲速度1150m/min所牽引時， 延伸倍率超過1.00倍則自拉伸率增加、延伸倍率1.20倍 • 下自拉伸率係成如所示的極大。使發現纖維的自拉伸性， 於結晶厚化之前結晶方向對於纖維軸，如何無規則地配 置，係爲考量的重點，所以考量於進行結晶化之前使纖維 大大地被收縮爲佳。因此，於纖維之延伸步驟中，比使用 溫水、蒸氣、或 Plate 型之 Heater(板式加熱器（Plate type Heater))進行之加熱延伸操作之際的延伸溫度，更低 的延伸溫度下實施1 ·〇5〜1.30倍之冷延伸，則一邊抑制經 由延伸之取向結晶化，可以擴大非晶部分的永久定型’對 於得本發明之複合纖維爲適合的。在此’ 「冷延伸」係指 -10- 200809022 於室溫下不只延伸、尙亦包含積極地至室溫以下的溫度所 冷卻之氛圍下進行延伸。具體而言，可舉出在室溫下之非 加熱狀態、或在室溫以下所冷卻之冷媒中延伸之方法。進 而具體的，可例舉適宜的在空氣中的冷延伸或冷水浴中延 伸之方法等。冷媒係如上述，除對空氣、水之外亦對於形 成本發明之複合纖維之纖維形成性樹脂成分及熱黏著性樹 脂成分爲惰性，可以適宜選擇對於沒有膨潤·溶解的稀有 氣體、氮、二氧化碳等之氣體、或PET及熱黏著性樹脂 成分不具有溶解性之各種的油等之液體。冷延伸時之冷媒 的溫度係〇〜30°c、較佳可給在10〜25t：。 因此於複合纖維之120°C中之自拉伸率超過1·〇%、即 複合纖維之120°C中之乾熱收縮率比-1.0%小，且爲將複合 纖維之100%拉伸時拉伸強度爲0.3〜1.0cN/dtex，延伸倍 率係須要在1.05〜1.30倍之範圍中。延伸倍率低於1.05 倍，貝ί] 100%拉伸時拉伸強度係成爲1.0cN/dtex以下、自 拉伸率變小於1.0%，無法達成本發明之目的。延伸倍率 超過 1.30 倍，則 100%拉伸時拉伸強度係超過 l.OcN/dtex。然後如彼之熱黏著性複合纖維100%之棉網所 成之熱黏著不織布中，無法得具有本發明目的之良好的懸 垂性之不織布。實施上述之延伸操作之際，延伸溫度係在 低的爲佳，以冷水作爲冷媒使用時，在0 °C以上2 5 t：以下 尤佳。如此之低溫下進行延伸操作，係從藉由緩熱延伸時 自複合纖維出的發熱，由於可抑制伴隨取向·發熱之結晶 化，對擴大所得之複合纖維之熱收縮率有貢獻。如上述地 -11 - 200809022 (9) 於本發明之複合纖維中係必須將1 00%拉伸應力在 0.3〜l.OcN/dtex。100%拉伸應力比〇.3cN/dtex小，則不織 布強度不足不織布的質地亦有變差的傾向；比L〇cN/dt ex 大，則自拉伸性或柔軟性（懸垂性）會變差而不佳。 製造本發明之複合纖維之際，紡絲速度係必須爲 1 3 00m/min以下、較佳爲 1 200m/min以下、更佳爲 10 0〜1 100m/min。紡絲速度超過 1 3 00m/min，則未延伸絲 φ 之取向提高，爲本發明之複合纖維之特徵，經由低倍率延 伸操作，使發現高的自拉伸率之效果係變少。 本發明之低模數的自拉伸性熱黏著性複合纖維之形 態，爲纖維形成性樹脂成分與熱黏著性樹脂成分，即所謂 以並列型所貼合之複合纖維，亦可纖維形成性樹脂成分爲 芯成分、熱黏著性樹脂成分作爲鞘成分之芯鞘型複合纖維 中任一者。但是，對於纖維軸方向，所有直角方向中，以 熱黏著性樹脂成分所配置而得之點，纖維形成性樹脂成分 # 作爲芯成分、熱黏著性樹脂成分作爲鞘成分之芯鞘型複合 纖維爲佳。又芯鞘型複合纖維，係可例舉同芯芯鞘型複合 纖維或偏芯芯鞘型複合纖維。 熱黏著性樹脂成分，係必須爲選擇結晶性熱可塑性樹 脂。爲非晶性熱可塑性樹脂，則紡絲時已取向之分子鏈熔 解的同時，隨著成爲無取向而大大地收縮。結晶性熱可塑 性樹脂之較佳的例子，可例舉聚烯烴系樹脂或結晶性共聚 聚酯等。 其聚烯烴系樹脂之例，可例舉結晶性聚丙烯、高密度 -12- 200809022 聚乙烯、中密度聚乙烯、低密度聚乙烯、或線狀低密度聚 乙烯等的結晶性聚烯烴樹脂。進而構成熱黏著性樹脂成分 之結晶性熱可塑性樹脂，係乙烯、丙烯、丁烯-1、戊烯_ 或丙烯酸、甲基丙烯酸、順丁烯二酸、延胡索酸、衣康 酸、巴豆酸、異巴豆酸、中康酸、檸康酸或Himic acid、 或此等之酯或此等之酸酐所成之不飽和化合物，其也可爲 至少1種以上上述之聚烯烴所共聚之共聚聚烯烴。 又，作爲熱黏著性樹脂成分使用之結晶性共聚聚酯之 例，較佳可例舉以下之聚酯。即，可例舉對苯二甲酸院二 酯中、以間苯二甲酸、萘-2,6-二羧酸、5-磺基間苯二甲酸 鈉、或者5-磺基間苯二甲酸鉀等的不可取代或具有磺酸 基之芳香族二羧酸、己二酸或者癸二酸等的脂肪族二竣 酸、1，4-環六亞甲基二羧酸等的脂肪族二羧酸、ω_羥烷基 羧酸、聚乙二醇、或者聚四甲二醇等的脂肪族二元醇、或環 六亞甲基-1，4_二甲醇等的脂環族二元醇爲呈現目的之熔點 所共聚之聚酯。其對苯二甲酸院二酯，係可例舉以主要的 二羧酸成分作爲對苯二甲酸或其酯形成性衍生物；主要的 二元醇成分作爲乙二醇、二甘醇、1，3丙二醇、伸丁二 醇、1，6-己二醇或自此等之衍生物將1〜3種組合作爲原料 使用所得之聚酯。又酯形成性衍生物，可例舉碳數爲1〜6 個之低級二烷基酯；碳數爲6〜1 0個之低級二芳基酯。較 佳之酯形成性衍生物爲二甲基酯或二苯酚酯。此等成分之 共聚率係爲呈現目的之熔點，期望藉由共聚成分進行各種 調節，以5〜50莫耳％爲較佳。又，本發明中之熱黏著性 -13- 200809022 樹脂成分，係纖維形成性樹脂成分爲PET時，熔點比 PET低20 °C以上之結晶性熱可塑性樹脂之2種以上亦可爲 聚合物所摻合的形態，沒有明顯阻礙黏著性或低熱收縮性 之範圍下，與非晶性熱可塑性樹脂或PET之熔點差，亦 可含有低於2(TC之結晶性熱可塑性樹脂。 本發明之低模數的自拉伸性熱黏著性複合纖維的斷裂 伸度係必須在130〜600%的範圍內，較佳爲170〜450%的範 圍內。本發明之複合纖維的斷裂伸度低於1 3 0%，則由於 熱黏著性樹脂成分之取向高，黏著性劣而不織布強度降 低。又，本發明之複合纖維的斷裂伸度超過600%，則實 質上的複合纖維之強度變太過於小、無法提高熱黏著不織 布的強度。 控制複合纖維的斷裂伸度在130〜6 00%的範圍內之方 法，雖受組合之聚合物的種類、熔融黏度左右，但可舉適 當選擇噴出聚合物之噴嘴的孔徑或紡絲速度的方法。此等 當中，亦可適當選擇作爲主要的紡絲速度，效果係大。進 而於本發明中，控制斷裂伸度於上述之範圍內，係也依據 聚合物的種類或組合，但以紡絲速度在100〜1 3 00m/分鐘 的範圍爲佳，若紡絲速度擴大則斷裂伸度控制爲小、若過 小的紡絲速度則可以擴大斷裂伸度。 本發明之低模數的自拉伸性熱黏著性複合纖維的 12 0t乾熱收縮率係具有比-1.0%小的特徵。乾熱收縮率之 下限係無特別限定，但推測下限爲-20.0%左右。製造熱黏 著不織布時，熱黏著之前複合纖維係藉由自拉伸，朝厚度 -14- 200809022 (12) 方向的厚度更爲突出之外，由於其不織布中模數爲低 維成取向厚度方向，考量厚度方向之壓縮時，成柔軟 感，使用於衛生材料之表面素材時等，對朝肌膚的垂 向之壓迫感係減輕，進而懸垂性也成良好。 本發明之熱黏著性複合纖維中，複合纖維的纖維 係同芯芯鞘型截面、或偏芯芯鞘型截面爲佳。並列型 維截面之複合纖維時，形成棉網時因顯現立體捲縮， φ 的收縮變大。又棉網的黏著強度也變小，本發明所指 果係多少可得減少。又，複合纖維的纖維截面可以爲 纖維、中空纖維，不限定在圓形截面，也可以橢圓截 3〜8葉截面等的多葉型截面、3〜8角形等的多角形截 的異形截面。其中多葉型截面，係表示具有如中心部 周方向像葉生長般的複數個凸部之截面形狀。 本發明之熱黏著性複合纖維中，複合纖維之纖度 需要選擇爲佳，雖沒有特別限定，通常爲〇 . 〇 1〜5 0 0 ® 左右的範圍下所使用。紡絲時藉由將樹脂所噴出之抽 的直徑在所欲定的範圍等，可達成此纖度範圍。 纖維形成性樹脂成分與熱黏著性樹脂成分之複合 沒有特別限定，但視爲目的之不織布或纖維結構體 度、容積、或熱收縮率之要求，而作選擇。纖維形成 脂成分與熱黏著性樹脂成分之比，以重量比爲1 〇/9〇〜 90/10左右爲佳。 纖維的形態係複合絲、單纖絲、人造纖維、短 (chop )、絲束等，視使用目的也可取任一之形態。 的纖 的觸 直方 截面 的纖 棉網 的效 實心 面、 面等 至外 係視 dt ex 絲頭 比雖 之強 性樹 纖維 本發 -15- 200809022 (13) 明之熱黏著性複合纖維，於作爲必要之梳棉機步驟之人造 纖維使用時，爲了賦予該熱黏著性複合纖維，良好的梳棉 機通過性，期望賦予適當的範圍之捲縮。本發明之熱黏著 性複合纖維尤其在纖維結構之無規則的的不織布中’懸垂 性提昇之效果爲顯著。因此’本發明之自拉伸性熱黏著性 複合纖維，係可以製造其單獨所成之不織布。視需要也可 與其它纖維混合製造不織布。製得不織布之方法，係以梳 φ 棉機法、氣流法、混式抄紙法等作棉網狀，再將此於熱風 乾燥機內或壓紋輥等加入所欲定的熱，將纖維之間彼此熱 黏著，而可以得伸懸長度値在1 〇cm以下之懸垂性優異之 柔軟的熱黏著性不織布。 【實施方式】 實施例 以下，藉由實施例更具體地說明本發明，但本發明不 因此受任何限定。又，實施例中各項目係以下述之方法測 定。 (1) 固有黏度（IV) 聚酯之固有黏度係計量聚合物於一定量，溶解於0-氯酚在0.012g/ml的濃度之後，依常法在351下求得。 (2) 熔融流率（Melt flow rate)(MFR) 熔融流率係按照日本工業標準K-7210條件4(測定溫 -16- 200809022 (14) 度190°C、載重2118N)測定。又，熔融流率爲以熔融紡 絲前之聚合物切片作爲樣品所測定之値。 (3) 熔點（Tm)、玻璃轉移溫度（Tg) 聚合物之熔點及玻璃轉移溫度係使用 TA Instruments · japan(股）公司製的熱分析 2200(Thermal ·200809022 (1) Nine, the invention belongs to the technical field of the invention. The present invention relates to a self-stretching thermal adhesion which has a low modulus and self-stretching when heat-bonded, and exhibits a soft touch when used as a heat-bonding non-woven fabric. Composite fiber and its manufacturing method. [Prior Art] Generally, a heat-adhesive resin component is used as a sheath, and a heat-bonding composite fiber which is a core-sheath type heat-adhesive composite fiber which is a core-forming resin component, is a carding method or an air method (air- After the formation of the fiber web, the hot-adhesive resin component is melted by a hot air dryer or a hot roll, and the interfiber bond is used as a non-woven fabric. Namely, since an organic solvent is not used as an adhesive for a solvent, the amount of harmful substances discharged from an organic solvent is small, which is advantageous. Further, since the production speed is increased and the cost associated with the reduction thereof is also large, it is widely used for fiber structures such as fiber cushions (hard cotton), mattresses, and the like. Among them, there is also a heat-adhesive non-woven fabric which represents a sanitary material such as a disposable diaper or a sanitary quilt. Since the non-woven fabric has direct contact with the skin, the non-woven fabric has the same softness or drapability as the cloth, and has a non-paper texture (paper- Like), moderately fluffy. Therefore, the non-woven fabric having such characteristics has been continuously betrayed from the beginning. One of the methods for thermally bonding the cotton web obtained from the heat-adhesive fibers is a hot roll method in which a part of the heat-bonded cotton web is softened or melt-bonded by an embossing roll or the like - 200808022. This method is easy to bend in the non-woven fabric at the boundary between the thermocompression bonding field and the non-thermal pressure bonding field, and the obtained non-woven fabric has excellent drapability. However, in order to flatten the fibers in the thermocompression bonding region, the pressed portions are hardened and the nonwovenness of the non-woven fabric is lost, and the obtained non-woven fabric only ends with a paper-like feeling. On the other hand, as another method of thermally adhering a cotton web obtained from the heat-adhesive fibers, there is a hot air method in which the hot air-softening fibers of the entire cotton web are softened or melted. In this method, the hot air is passed through the state in which the volume of the cotton web is left to a certain extent, so that the obtained non-woven fabric has a bulkiness, and the obtained non-woven fabric does not have a part of hardening, and the surface contact is smooth. On the one hand, when the non-woven fabric is bent, the non-woven fabric is prone to irregular creases and is a non-woven fabric with poor drape. As a solution thereto, the following method is disclosed in Patent Document 1. In other words, the orientation index of the heat-adhesive resin component is 25% or less by the high-speed spinning method, and the orientation index of the fiber-forming resin component is 40% or more, and the adhesive strength is strong, and the fusion is performed at a low temperature, and the heat shrinkage ratio is obtained. Small heat-adhesive composite fiber. The hybrid cotton web of the heat-adhesive composite fiber and the non-heat-adhesive fiber is adhered by a hot air method, and is a technique for producing a non-woven fabric having drapability and bulkiness and having sufficient non-woven strength. However, the high-speed spinning method has insufficient stability and poor yield in the current short-fiber manufacturing process. Further, considering the performance of the obtained short fibers, the cost performance is insufficient, and the commercial production of short fibers by the high-speed spinning method can be said to have many difficult problems. Moreover, when the heat-adhesive composite fiber is formed into a heat-adhesive non-woven fabric alone, since the number of intersections in the non-woven fabric is increased, it is difficult to obtain a non-woven fabric having a soft touch, and it is difficult to obtain a non-woven fabric having a soft touch. The tendency to be poorly woven. Therefore, in general, non-woven fabrics are produced by mixing non-heat-adhesive fibers with a reduced number of adhesive intersections. However, in this case, the number of adhesive intersections in the nonwoven fabric is reduced, so that the strength of the nonwoven fabric tends to decrease. Therefore, the non-woven strength and the soft touch are not necessarily sufficient levels. In addition, the fiber-forming resin component is a composite fiber constituting a core component, and an example of a heat-adhesive composite fiber having a core component of polyethylene terephthalate (hereinafter referred to as PET) is disclosed in Patent Document 1. Not revealed. When the core component of the heat-adhesive composite fiber is PET, and the core component of the heat-adhesive composite fiber is polypropylene (hereinafter, PP), the melting point of the core component can be made higher than the melting point of the sheath component, and can be further improved. The thermal adhesion strength of the resulting nonwoven fabric. Further, since such a core component has high rigidity as a composite fiber of PET, it is possible to obtain a more bulky nonwoven fabric. However, the nonwoven fabric is produced by using the low-expansion-stretched composite fiber or the unstretched composite fiber as described in Patent Document 1, and the thermal shrinkage system becomes large because the orientation crystallinity of the core component of the composite fiber to be used is insufficient. . Further, when high-speed spinning as described in Patent Document 1 or a composite fiber using a core component as PET is used, in order to prevent rapid solidification of the core component, it is necessary to improve the melting temperature of the core component of the composite fiber at the time of spinning. The melting temperature of the sheath component of the fiber. As a result, the deterioration of the polymer constituting the sheath component and the spinning draft are large, so that the yarn breakage is very likely to occur at the time of spinning. SUMMARY OF THE INVENTION The present invention has been made in view of the above-described prior art, and an object thereof is to provide a polyethylene terephthalate. The alcohol ester is used as a fiber-forming resin component, and a low-modulus self-stretching heat-adhesive composite fiber having a high-adhesion strength, a bulky and good drapability of a nonwoven fabric or a fiber structure can be produced. The inventors of the present invention have found that, as a result of the above-mentioned problem, the present inventors have found that a crystalline thermoplastic resin having a melting point lower than 20° (less than PET) is used as a heat-adhesive resin component. The unstretched yarn drawn by the spinning speed of 300 m/min or less is subjected to non-heating or in a refrigerant, and is cooled by 1.05 to 1.30 times while cooling, and the glass transition temperature and the fiber-forming resin component of the heat-adhesive resin component are Both of the glass transition temperatures are tempered by shrinking at a temperature higher than 1 °C, and the invention achieves high adhesion strength, sufficient bulkiness and drapability, and PET is used as a low modulus of the fiber-forming resin component. More specifically, the above-mentioned problem is a composite fiber which is a fiber-forming resin component and a heat-adhesive resin component, and is characterized in that the fiber-forming resin component is agglomerated. In the case of ethylene terephthalate, the heat-adhesive resin component has a crystallinity lower than the fiber-forming resin component by 20 ° C or more. Made of thermoplastic resin, tensile elongation is 130~600%, 100% tensile stress is 0.3~l.OcN/dtex, dry heat shrinkage ratio at 120°C is -1.0% small, self-stretching of 200809022 (5) The invention solves the problem of the thermal adhesive composite fiber. Further, the above problem can be achieved by heat-bonding after the cold extension of the unstretched filament of the composite fiber drawn at a spinning speed of 1 300 m/min or less is 1.05 to 1.30 times. The glass transition temperature of the resin component and the glass transition temperature of the fiber-forming resin component are solved by a method for producing a heat-adhesive composite fiber characterized by relaxation heat shrinkage at a temperature of 10 ° C or higher. The low-modulus self-stretching heat-adhesive composite fiber, the non-woven fabric produced, does not undergo the reduction of the adhesion point of the non-heat-adhesive fiber, and also exhibits the low modulus characteristic of the heat-bonding composite fiber itself. And the soft touch according to the self-stretching property, and at the same time, the non-woven fabric retains the high adhesive strength peculiar to the heat-adhesive non-woven fabric formed by the heat-adhesive composite fiber alone. In the above, the present invention is a composite fiber composed of a fiber-forming resin component and a heat-adhesive resin component. More specifically, the fiber-forming resin component is lower in PET than PET. A crystalline thermoplastic resin having a melting point of 20 ° C or more as a low modulus self-stretching heat-adhesive composite fiber of a heat-adhesive resin component, wherein a difference in melting point between the PET and the heat-adhesive resin component is less than 2 ( In the step of melting the heat-adhesive resin component to adhere the TC, the fiber-forming resin component is also dissolved, and the non-woven -8 - (6) (6) 200809022 cloth or fiber structure having high adhesion strength cannot be produced. Not good. The range of the difference in melting point is preferably in the range of 20 to 180 °C. The composite fiber is obtained by a known melting method of a composite fiber or a spinning head, and the spinning speed is from 1 〇〇 to 1 300 00 m/min to obtain an unstretched yarn, followed by a cold extension of 1.05 to 1.30 times, and further the glass transition temperature of the PET. (hereinafter, T g ) is preferably 1 ° ° C or more higher than the Tg of the thermoplastic resin resin constituting the heat-adhesive resin component, and is preferably 10 ° C or lower lower than the melting point of the heat-adhesive resin component. It can be obtained by a relaxation heat shrinkage treatment at a temperature higher than 20 ° C and higher than the melting point of the heat-adhesive resin component by 20 ° C or lower. Specifically, the temperature higher than the Tg of the Tg of PET and the Tg of the thermoplastic resin of the heat-adhesive resin component is higher than the temperature of PET (about 70 Å) in many cases. Therefore, it is preferred to carry out the relaxation heat shrinkage treatment at a temperature of 80 ° C or higher, preferably 90 ° C or higher. More preferably, the temperature is above 100 °C. The temperature during this relaxation heat shrinkage treatment can be carried out in hot air or warm water. In the present invention, the melting point of the crystalline thermoplastic resin constituting the heat-adhesive resin component is as low as 20 ° C or more lower than the melting point of PET, so that the Tg ratio of the thermoplastic crystalline resin constituting the heat-adhesive resin component is The Tg of PET is much lower. When the temperature of the relaxation heat shrinkage treatment is lower than this temperature range, the shrinkage ratio of the composite fiber when it is thermally adhered becomes poor. When the temperature of the slow heat shrinkage treatment is too high in this temperature range, the resin of the heat-adhesive resin component may be softened and may be pseudo-adhesive. The tempering heat shrinkage treatment may be such that the stretched tow has no tension, and by means of hot air, it can also be super-fed in the warm water without tension like 〇5~0.85 times. method. 200809022 By the relaxation heat shrinkage treatment described above, the fiber which is subjected to the low-magnification stretching is contracted in the fiber axis direction by permanent setting to form a crystal having a crystal axis inclined from the fiber axis direction toward the irregular direction. Further, by the application of the temperature, the crystals of the crystals become larger in size, and the adjacent crystals are brought into contact with each other, and the crystal size is further increased. In this way, it appears that the fiber is elongated. This phenomenon is called self-stretching, and this self-stretching property is exhibited in the composite fiber of the present invention. φ This phenomenon is a more significant phenomenon at high speed spinning at a spinning speed of 2000 m/min or more. According to the begging of the present inventors, in the case of an unstretched yarn obtained at a spinning speed of 1 300 m/min or less, elongation is performed only at a few magnifications, and then self-stretching is found by a method of slowing heat shrinkage. The rate can be larger and the present invention is completed. For example, a core-sheath type composite fiber in which the core component is PET (intrinsic viscosity: IV = 0.64 dL/g) and the sheath component is high-density polyethylene (MER = 20 g/10 min) is stretched at a spinning speed of 1150 m/min. When the magnification exceeds 1.00, the self-stretching rate increases and the stretching ratio is 1.20 times. • The lower self-stretching ratio is as great as shown. It has been considered that the self-stretching property of the fiber is irregularly arranged with respect to the fiber axis before the crystal thickening, and it is considered that the fiber is greatly shrunk before the crystallization. Therefore, in the fiber stretching step, the elongation temperature at the time of the heating extension operation using a warm water, a vapor, or a Plate type Heater (Plate type Heater) is performed at a lower elongation temperature. In the case of cold stretching of 〇5 to 1.30 times, it is possible to increase the permanent crystallization of the amorphous portion while suppressing crystallization by stretching, and it is suitable for the conjugate fiber of the present invention. Here, "cold extension" means that -10- 200809022 extends not only at room temperature, but also in an atmosphere cooled to a temperature below room temperature. Specifically, a method of extending in a non-heated state at room temperature or a refrigerant cooled at room temperature or lower can be mentioned. Further, a specific method such as a cold stretching in air or a stretching in a cold water bath can be exemplified. As described above, the refrigerant is inert to the fiber-forming resin component and the heat-adhesive resin component which form the conjugate fiber of the present invention in addition to air and water, and can be suitably selected for a rare gas, nitrogen, or carbon dioxide which is not swelled and dissolved. The gas, or the PET and the heat-adhesive resin component do not have a liquid such as various oils which are soluble. The temperature of the refrigerant at the time of cold stretching is 〇30 ° C, preferably 10 to 25 t:. Therefore, the self-expansion ratio in the 120° C. of the composite fiber exceeds 1·〇%, that is, the dry heat shrinkage ratio in the 120° C. of the composite fiber is smaller than −1.0%, and when the composite fiber is stretched by 100%. The tensile strength is 0.3 to 1.0 cN/dtex, and the stretching ratio is required to be in the range of 1.05 to 1.30 times. When the stretching ratio is less than 1.05 times, the tensile strength at 100% stretching is 1.0 cN/dtex or less, and the self-stretching ratio is less than 1.0%, and the object of the present invention cannot be attained. When the stretching ratio exceeds 1.30 times, the tensile strength at 100% stretching exceeds l.OcN/dtex. Then, in the heat-bonding non-woven fabric made of 100% of the heat-adhesive composite fiber, it is impossible to obtain a non-woven fabric having a good drapability for the purpose of the present invention. When the above extension operation is carried out, the elongation temperature is preferably low, and when cold water is used as the refrigerant, it is preferably 0 ° C or more and 2 5 t: or less. When the stretching operation is carried out at a low temperature, the heat generated from the conjugate fiber when the film is stretched by heat is suppressed, and the crystallization of the conjugate fiber obtained by the expansion can be suppressed. As described above, -11 - 200809022 (9) In the composite fiber of the present invention, it is necessary to set a tensile stress of 100% to 0.3 to 1.0 OcN/dtex. When the 100% tensile stress is smaller than 〇.3cN/dtex, the texture of the non-woven fabric is less than that of the non-woven fabric, and the texture is also deteriorated. If it is larger than L〇cN/dt ex, the self-stretching property or the flexibility (drapability) may change. Poor. When the composite fiber of the present invention is produced, the spinning speed must be 1 300 m/min or less, preferably 1 200 m/min or less, more preferably 10 0 to 1 100 m/min. When the spinning speed exceeds 1 3 00 m/min, the orientation of the unstretched yarn φ is improved, which is a feature of the composite fiber of the present invention, and the effect of finding a high self-stretching ratio is reduced by the low-magnification stretching operation. The form of the low modulus self-stretching heat-adhesive composite fiber of the present invention is a fiber-forming resin component and a heat-adhesive resin component, that is, a composite fiber which is bonded in a side-by-side type, or a fiber-forming resin. The component is a core-sheath type composite fiber in which a core component and a heat-adhesive resin component are sheath components. However, in the direction of the fiber axis, the core-sheath type composite fiber in which the fiber-forming resin component # is a core component and the heat-adhesive resin component is used as a sheath component in all the right-angle directions is obtained by the heat-adhesive resin component. good. Further, the core-sheath type composite fiber may be a core-sheath type composite fiber or an eccentric core-sheath type composite fiber. The heat-adhesive resin component must be a crystalline thermoplastic resin. In the case of the amorphous thermoplastic resin, the molecular chain which has been oriented during spinning is melted, and it shrinks greatly as it becomes non-oriented. A preferred example of the crystalline thermoplastic resin may, for example, be a polyolefin resin or a crystalline copolymer polyester. The polyolefin resin may, for example, be a crystalline polyolefin resin such as crystalline polypropylene, high density -12-200809022 polyethylene, medium density polyethylene, low density polyethylene, or linear low density polyethylene. Further, a crystalline thermoplastic resin constituting a heat-adhesive resin component is ethylene, propylene, butene-1, pentene _ or acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, crotonic acid, or different An unsaturated compound obtained by crotonic acid, mesaconic acid, citraconic acid or Himic acid, or an ester thereof or an acid anhydride thereof may be a copolymerized polyolefin copolymerized with at least one of the above polyolefins. Further, as an example of the crystalline copolymerized polyester used as the heat-adhesive resin component, the following polyesters are preferable. That is, in the terephthalic acid terephthalate, isophthalic acid, naphthalene-2,6-dicarboxylic acid, sodium 5-sulfoisophthalate, or potassium 5-sulfoisophthalate may be mentioned. An aliphatic dicarboxylic acid such as an aliphatic dicarboxylic acid such as an aromatic dicarboxylic acid having a sulfonic acid group, an adipic acid or a sebacic acid, or a 1,4-sulfonyl hexamethylene dicarboxylic acid; An aliphatic diol such as ω_hydroxyalkylcarboxylic acid, polyethylene glycol or polytetramethylene glycol, or an alicyclic diol such as cyclohexamethylene-1,4-dimethanol The polyester copolymerized by the melting point of the purpose. The terephthalic acid diester is exemplified by a main dicarboxylic acid component as a terephthalic acid or an ester-forming derivative thereof; and a main glycol component as ethylene glycol, diethylene glycol, or 1, 3 propylene glycol, butanediol, 1,6-hexanediol or a derivative derived therefrom, the obtained polyester is used as a raw material in a combination of 1 to 3 kinds. Further, the ester-forming derivative may, for example, be a lower dialkyl ester having 1 to 6 carbon atoms; or a lower diaryl ester having 6 to 10 carbon atoms. A preferred ester-forming derivative is a dimethyl ester or a diphenol ester. The copolymerization ratio of these components is the melting point for the purpose, and it is desirable to carry out various adjustments by the copolymerization component, preferably 5 to 50 mol%. In the case of the resin component of the present invention, when the fiber-forming resin component is PET, two or more kinds of crystalline thermoplastic resins having a melting point lower than that of PET by 20 ° C or more may be a polymer. The blended form may have a difference in melting point or low heat shrinkage, and may have a difference between the melting point of the amorphous thermoplastic resin or PET, and may also contain a crystalline thermoplastic resin of less than 2 (TC). The elongation at break of the modulus self-stretching heat-adhesive composite fiber must be in the range of 130 to 600%, preferably 170 to 450%. The rupture elongation of the conjugate fiber of the present invention is less than 1 30%, since the orientation of the heat-adhesive resin component is high, the adhesiveness is inferior and the weaving strength is lowered. Further, when the elongation at break of the composite fiber of the present invention exceeds 600%, the strength of the substantially composite fiber becomes too small. The strength of the heat-bonding non-woven fabric cannot be improved. The method of controlling the elongation at break of the composite fiber in the range of 130 to 600% is subject to the type of the polymer to be combined and the melt viscosity, but the polymer can be appropriately selected. The method of the aperture or the spinning speed of the nozzle. Among them, the main spinning speed can be appropriately selected, and the effect is large. Further, in the present invention, the controlled elongation at break is within the above range, and is also based on polymerization. The type or combination of the materials is preferably in the range of 100 to 1 300 m/min at the spinning speed, and the elongation at break is controlled to be small if the spinning speed is increased, and the elongation at break can be increased if the spinning speed is too small. The 120 t dry heat shrinkage ratio of the low modulus self-stretching heat-adhesive composite fiber of the present invention has a characteristic of less than -1.0%. The lower limit of the dry heat shrinkage ratio is not particularly limited, but the lower limit is estimated to be -20.0. When manufacturing a heat-bonded non-woven fabric, the composite fiber is more self-stretched before the heat-bonding, and the thickness is more prominent in the thickness direction of the thickness -14-200809022 (12), because the modulus in the non-woven fabric is low-dimensional orientation. In the thickness direction, when it is compressed in the thickness direction, it is soft, and when used on the surface material of a sanitary material, the pressure on the vertical direction of the skin is reduced, and the drape is also good. The thermal adhesiveness of the present invention is good. In the composite fiber, the fiber of the composite fiber is preferably the same as the core core-sheath cross section or the eccentric core sheath type cross section. When the composite fiber of the side-by-side cross-section is formed, the shrinkage of φ becomes large when the cotton web is formed due to the three-dimensional crimping. Moreover, the adhesion strength of the cotton web is also small, and the degree of the invention can be reduced. In addition, the fiber cross section of the composite fiber can be fiber or hollow fiber, and is not limited to a circular cross section, and can also be an elliptical cut 3~8. A multi-lobed cross-section such as a leaf cross section, or a polygonal cross-section shaped cross section such as a 3 to 8 angle shape, wherein the multi-lobed cross section has a cross-sectional shape having a plurality of convex portions such as a leaf growth in the circumferential direction of the center portion. In the heat-adhesive composite fiber of the invention, the fineness of the composite fiber needs to be selected, and although it is not particularly limited, it is usually used in the range of about 〜1 to 5 0 0 ® . This fineness range can be achieved by spinning the diameter of the resin to be ejected in a desired range during spinning. The combination of the fiber-forming resin component and the heat-adhesive resin component is not particularly limited, but is selected as a non-woven fabric, a fiber structure, a volume, or a heat shrinkage rate. The ratio of the fiber-forming fat component to the heat-adhesive resin component is preferably from about 〇/9〇 to about 90/10 by weight. The form of the fiber is a composite yarn, a monofilament, a rayon, a chop, a tow, etc., and may be in any form depending on the purpose of use. The fiber-touching cross-section of the fiber-reinforced cotton web has a solid surface, a surface, etc., and the external line of the dt ex silk head is stronger than the tree fiber. The hair is -15-200809022 (13) The heat-adhesive composite fiber of the Ming In the use of the man-made fiber of the necessary carding step, in order to impart good passability to the heat-adhesive composite fiber, it is desirable to impart a suitable range of crimping. The heat-adhesive composite fiber of the present invention has a remarkable effect of improving the drape property particularly in the irregular nonwoven fabric of the fiber structure. Therefore, the self-stretchable heat-adhesive composite fiber of the present invention can be produced into a nonwoven fabric which is formed separately. Non-woven fabrics can also be mixed with other fibers as needed. The method for producing the non-woven fabric is a cotton mesh method by a comb φ cotton machine method, a gas flow method, a mixed paper making method, etc., and then adding the desired heat to the hot air dryer or the embossing roller, etc. They are heat-bonded to each other, and a soft, heat-adhesive non-woven fabric excellent in drape length of 1 〇cm or less can be obtained. [Embodiment] Hereinafter, the present invention will be specifically described by way of Examples, but the present invention is not limited thereto. Further, each item in the examples was measured by the following method. (1) Intrinsic viscosity (IV) The intrinsic viscosity of the polyester is measured in a certain amount and dissolved in 0-chlorophenol at a concentration of 0.012 g/ml, which is obtained at 351 by a conventional method. (2) Melt flow rate (MFR) The melt flow rate was measured in accordance with Japanese Industrial Standard K-7210 Condition 4 (measurement temperature -16 - 200809022 (14) degree 190 ° C, load 2118N). Further, the melt flow rate was measured by using a polymer chip before melt spinning as a sample. (3) Melting point (Tm), glass transition temperature (Tg) The melting point of the polymer and the glass transition temperature are determined by TA Instruments · japan (2) Thermal Analysis 2200 (Thermal
Analyst 2 200)，升溫速度以20°C/分鐘測定。 (4) 纖度 複合纖維之纖度係藉由日本工業標準 L- 1 01 5 :2005 8 · 5 · 1 A法中記載的方法測定。 (5) 強度·伸度、100%拉伸應力 複合纖維的強度·伸度、100%拉伸應力係藉由曰本 工業標準L- 1 0 1 5:2005 8.7.1法中記載的方法測定。本發 • 明之複合纖維係藉由定長熱處理之效率，因於強度·伸度、 1 00%拉伸應力中易產生偏差，故於單絲中測定強度·伸 度、1 0 0%拉伸應力時係有必要增加測定點數。測定點數 係5 0以上爲佳，故在此測定點數作5 0，作爲其平均値， 定義各個的値。又，由讀取此強度·伸度測定之際之載 重-畸變差曲線之伸度100%時點之應力，可以測定100% 拉伸應力。 (6) 捲縮數、捲縮率 -17- 200809022 (15) 複合纖維之捲縮數、捲縮率係藉由日本工業標準1_ 1 0 1 5:2005 8. 1 2.1〜8.12.2法中記載的方法測定。 (7) 120°C乾熱収縮率 複合纖維之12 0°C乾熱収縮率係於日本工業標準1-1 0 1 5:2005 8.1 5 b)中，在 120°C下實施。 (8) 棉網面積收縮率 複合纖維棉網面積收縮率係藉由以下手法測定。作成 切斷纖維長在51mm之熱黏著性複合短纖維100%所成之 基重（basis weight) 30g/m2之梳棉機棉網，切斷其棉網成 25cmx25cm。接著，其切斷之棉網維持在150°C之熱風乾 燥機（佐竹化學機械工業股份有限公司製熱風循環恆溫乾 燥器：41-S4)中放置2分鐘後進行熱處理，進行複合纖維 彼此之熱黏著。測定熱黏著後之棉網的長寬尺寸以乘法算 出面積Ai，求得下述之式之面積收縮率。 面積收縮率（％)=〔 （Α〇— Αι) / Α〇〕χ10 0 上式中，A〇 = 5cmx5cm = 625(cnf ) (9) 不織布強度（黏著強度） 藉由上述的方法得到的熱黏著後之棉網（厚度5mm)， 朝機器方向（不織布製造步驟之纖維或棉網之行進方向）切 -18- 200809022 (16) 出覧5cm、長20cm的試片，以抓間隔1〇cm、拉伸速度 2〇Cm/min測定拉伸強度。黏著強度係拉伸斷裂力以試片 重量除得之値。 (1〇)剛軟性（伸懸長度（cantilever)値） 藉由上述的方法得到的熱黏著後之棉網（厚度5mm)， 朝機器方向切出寬2.5cm、長25cm的試片，經由日本工 業標準L - 1 0 8 6 : 1 9 8 3 6 · 1 2.1之方法測定。表示僅機器方向 的伸懸長度値。 伸懸長度値之具體的測定手法係如以下。亦即一端具 有45度之斜面，表面光滑的水平台上放置沿台切出的試 片。接著其試片之一端正確地於水平台之斜面側之一端 (45度之斜面與水平台的接合部分）接合，試片的其它端之 位置，以其4 5度之斜面側的一端之長度來測定。因試片 之長度爲25cm，故此値成25cm。其次藉由適當的方法， 使試片朝斜面的方向緩慢地滑動’試片之一端的中央點係 達到其斜面與同一面時，其它端的位置，以其4 5度之斜 面側的一端之長度來測定。此値作爲測定値A。25cm與 此測定値A之差爲伸懸長度値。對各個試片5片之正反 面測定，平均値作爲其試片的伸懸長度値。此伸懸長度値 愈大，試片係硬，表示試片之懸垂性差’此伸懸長度値愈 小，試片係柔軟，表示試片之懸垂性爲良好的。 實施例1 -19- 200809022 (17) 芯成分（纖維形成性樹脂成分）中IV = 〇.64dL/g、 Tg = 7 0°C、Tm = 2 5 6t：之聚對苯二甲酸乙二醇酯（PET)於鞘成 分（熱黏著性樹脂成分）中使用 MFR = 20g/10min、 Tm=131°C(Tg係低於零度）之高密度聚乙烯（HDPE)。將彼 等之樹脂各熔融成290°C、250°C後，使用周知的芯鞘型複 合纖維用抽絲頭，爲將芯成分重量比率與鞘成分重量比率 成50wt% : 50wt%之重量比率，形成複合纖維，故以噴出 φ 量〇.70g/min/孔、紡絲速度1150m/min的條件下進行紡 絲，得到未延伸絲。將其未延伸絲冷延伸1.20倍之後， 於月桂基磷酸酯鉀鹽與聚環氧乙烯改性聚矽氧烷爲 80wt%:20wt%所成之油劑的水溶液中浸漬冷延伸後的絲 條，使用附有塡料箱的擠壓型捲縮裝置（CRIMPER)賦予 1.1個/2 5mm之機械捲縮。進而賦予其捲縮之絲條於鬆弛 下，比芯成分之玻璃轉移溫度高40°C的110°C之熱風下， 進行弛緩熱收縮處理及乾燥處理後，切斷成纖維長 Φ 5 1 mm。所得到之熱黏著性複合纖維之單絲纖度爲 6.4dtex、強度 0.76cN/dtex、伸度 442%、100%拉伸應力 0 · 3 7 c N / d t e X、1 2 0 °C乾熱收縮率-2 · 6 %。此熱黏著性複合纖 維100%所成之棉網的棉網面積收縮率爲-7.5%、不織布強 度15.1kg/g、伸懸長度値8.50cm。 比較例1 於實施例1得到的未延伸絲於70 °C的溫水中進行2.5 倍的延伸，繼續除了於90°C溫水中進行1.2倍的延伸之 -20- 200809022 (18) 外，同實施例1的條件下製造出複合纖維。所得到的熱黏 著性複合纖維之單絲纖度爲2.6dtex、強度2.49cN/dtex、 伸度37.1%、120°C乾熱收縮率2·5%。熱黏著性複合纖維 的伸度因未達100%，故1〇〇%拉伸應力係無法測定出。此 熱黏著性複合纖維100%所成之棉網的棉網面積收縮率爲 5%、不織布強度20.5kg/g、伸懸長度値12.90cm。 比較例2 除不施行延伸處理之外，與實施例1同樣的條件下製 造出複合纖維。所得到的熱黏著性複合纖維之單絲纖度爲 6.47dtex、強度 0 · 6 0 cN/d t e x、伸度 4 6 0 · 3 %、1 0 0 % 拉伸應 力0.37cN/dtex、120°C乾熱收縮率·〇·7%。此熱黏著性複 合纖維1 0 0 %所成之棉網的棉網面積收縮率爲-1.4 5 %、不 織布強度14.5kg/g、伸懸長度値7.90cm。 • 實施例2 除冷延伸的延伸倍率爲1.1倍之外，與實施例1同樣 的條件下製造出複合纖維。所得到的熱黏著性複合纖維之 單絲纖度爲 6.41dtex、強度 0.65cN/dtex、伸度 424.1 %、 1 0 0 %拉伸應力 〇 · 4 1 c N / d t e X、1 2 0 °C乾熱收縮率-1.9 %。此 熱黏著性複合纖維1〇〇%所成之棉網的棉網面積收縮率爲 -5.6%、不織布強度16· 5kg/g、伸懸長度値8.10cm。 實施例3 -21 - 200809022 除冷延伸的延伸倍率爲1.30倍之外，與實施例1同 樣的條件下製造出複合纖維。所得到的熱黏著性複合纖維 之單絲纖度爲 6.22dtex、強度 0.72cN/dtex、伸度 381.8%、100% 拉伸應力 〇.46cN/dtex、120°C 乾熱收縮率 -2.0%。此熱黏著性複合纖維100%所成之棉網的棉網面積 收縮率爲-6.1%、不織布強度 17.1kg/g、伸懸長度値 8.9 0cm 〇 比較例3 除冷延伸的延伸倍率爲1.4倍之外，與實施例1同樣 的條件下製造出複合纖維。所得到的熱黏著性複合纖維之 單絲纖度爲 6.14dtex、強度 0.75cN/dtex、伸度 346.8%、 100%拉伸應力 0.53cN/dtex、120°C乾熱收縮率- 0.6%。此 熱黏著性複合纖維1 〇〇%所成之棉網的棉網面積收縮率爲 -1.8%、不織布強度18.4kg/g、伸懸長度値10.1cm。 實施例4 除將冷延伸控制於水溫2 0 t：之水浴中一邊冷卻一邊進 行之外，與實施例1同樣的條件下製造出複合纖維。所得 到的熱黏著性複合纖維之單絲纖度爲 6.52dtex、強度 0,65CN/dtex、伸度 459.3 %、100%拉伸應力 〇.39cN/dtex、 120°C乾熱收縮率-3·2%。此熱黏著性複合纖維1〇〇%所成 之棉網的棉網面積收縮率爲-9.5%、不織布強度15.3kg/g 、伸懸長度値8.1 3 c m。 -22- 200809022 實施例5 弛緩熱收縮處理及熱處理於95°C的溫水浴中以0.7倍 的超餵進行，除其後的熱風乾燥不進行之外，與實施例1 同樣的條件下製造出複合纖維。所得到的熱黏著性複合纖 維之單絲纖度爲 6.58dtex、強度 〇.68cN/dtex、伸度 443.3%、100% 拉伸應力 〇.41cN/dtex、120°C 乾熱收縮率 -3.9%。此熱黏著性複合纖維100%所成之棉網的棉網面積 收縮率爲-11.4%、不織布強度14.9kg/g、伸懸長度値 8.9 0 cm 〇 實施例6 芯成分（纖維形成性樹脂成分）中IV = 0.64dL/g、 Tg = 7 0°C、Tm = 2 5 6°C之聚對苯二甲酸乙二醇酯（PET)於鞘成 分（熱黏著性樹脂成分）中使用 MFR二40g/10min、 Tm=152°C、Tg = 4 3°C之結晶性共聚聚酯（使用間苯二甲酸 20莫耳％、共聚之四甲二醇）50莫耳％之聚對苯二甲酸乙 二醇酯、各熔融成290°C、25 5 °C後，使用周知的芯鞘型複 合纖維用抽絲頭，將芯成分重量比率與鞘成分重量比率成 爲 5 0wt% : 5 0wt%之重量比率，形成複合纖維，噴出量 O jlg/min/iL、紡絲速度1 250m/min下進行紡絲，得到未 延伸絲。將其未延伸絲冷延伸1.2倍之後，於月桂基磷酸 酯鉀鹽與聚環氧乙烯改性聚矽氧烷爲80wt%:20wt%所成之 油劑的水溶液中浸漬冷延伸後之絲條之後，使用附有塡料 -23- 200809022 (21) 箱的擠壓型捲縮裝置賦予11個/25mm之機械捲縮。進而 賦予其捲縮之絲條於鬆弛下，在9 0 °C的熱風中施行乾燥與 驰緩熱處理後，切斷成纖維長5 1 mm。所得到之熱黏著性 複合纖維之單絲纖度爲5.7dtex、強度0.94cN/dtex、伸度 392%、100%拉伸應力〇.35cN/dtex、120°C乾熱收縮率-3.8%。此熱黏著性複合纖維100%所成之棉網的棉網面積 收縮率（但是，熱黏著溫度係變更成1 8 0 °C )爲-1 1 · 2 %、不 織布強度12.3kg/g、伸懸長度値8.30cm。 產業上之可利用性 本發明之低模數的自拉伸性熱黏著性複合纖維’係使 用PET做爲纖維形成性樹脂成分，且製造時之紡絲速度 小，故紡絲時的斷絲明顯地少。進而使用其複合纖維製造 不織布，則可得高黏著性、高懸垂性、且觸感良好之蓬鬆 的不織布。 -24-Analyst 2 200), the rate of temperature increase was measured at 20 ° C / min. (4) Fineness The fineness of the composite fiber is measured by the method described in Japanese Industrial Standard L-10.00 5:2005 8 · 5 · 1 A. (5) Strength, elongation, 100% tensile stress The strength, elongation, and 100% tensile stress of the composite fiber are determined by the method described in the method of 8.7.1 of this industrial standard L- 1 0 1 5:2005. . According to the efficiency of the fixed length heat treatment, the composite fiber of the present invention has a strength, an elongation, and a tensile stress of 100%. Therefore, the strength and elongation, and 100% elongation are measured in the monofilament. In the case of stress, it is necessary to increase the number of measurement points. Since the number of measurement points is preferably 50 or more, the number of points is measured as 50, and as the average value, each 値 is defined. Further, the 100% tensile stress can be measured by reading the stress at the point of 100% elongation of the load-distortion difference curve at the time of measuring the strength and elongation. (6) Number of crimps, crimp ratio -17- 200809022 (15) The number of crimps and crimp ratio of composite fibers are based on Japanese Industrial Standards 1_ 1 0 1 5:2005 8. 1 2.1~8.12.2 The method described is measured. (7) Dry heat shrinkage ratio at 120 °C The dry heat shrinkage ratio of the composite fiber at 12 °C was carried out at 120 °C in Japanese Industrial Standard 1-1 0 1 5:2005 8.1 5 b). (8) Shrinkage area of cotton web The area shrinkage of composite fiber cotton web is determined by the following method. A cotton web of a card having a basis weight of 30 g/m 2 formed by cutting 100% of the heat-adhesive composite short fibers having a fiber length of 51 mm was cut, and the cotton web was cut into 25 cm x 25 cm. Then, the cut cotton web was placed in a hot air dryer (Suzuki Chemical Machinery Co., Ltd. hot air circulating constant temperature dryer: 41-S4) at 150 ° C for 2 minutes, and then heat-treated to heat the composite fibers. Adhesive. The area width and width of the cotton web after the heat adhesion were measured, and the area Ai was calculated by multiplication to obtain the area shrinkage ratio of the following formula. Area shrinkage ratio (%) = [(Α〇— Αι) / Α〇]χ10 0 In the above formula, A〇= 5cmx5cm = 625(cnf ) (9) Non-woven strength (adhesive strength) Heat obtained by the above method Adhesive cotton web (thickness 5mm), cut to the machine direction (the direction of the fiber or cotton web in the non-woven manufacturing step) -18- 200809022 (16) The test piece with a length of 5cm and a length of 20cm is taken at a distance of 1〇cm The tensile strength was measured at a tensile speed of 2 〇 Cm/min. The adhesive strength is the tensile breaking force which is divided by the weight of the test piece. (1〇) softness (cantilever) 热 The heat-adhered cotton web (thickness: 5 mm) obtained by the above method, cut a test piece 2.5 cm wide and 25 cm long in the machine direction, via Japan Industrial Standard L - 1 0 8 6 : 1 9 8 3 6 · 1 2.1 Method determination. Indicates the length of the machine only. The specific measurement method for the length of the suspension is as follows. That is, a test piece cut along the table is placed on the water platform with a smooth surface on one end with a 45 degree slope. Then one of the test pieces is correctly joined to one end of the inclined side of the water platform (the 45-degree inclined surface is joined to the joint of the water platform), and the other end of the test piece is at the end of the inclined side of the 45-degree side. To determine. Since the length of the test piece is 25 cm, it is 25 cm. Secondly, by a suitable method, the test piece is slowly slid in the direction of the slope. When the center point of one end of the test piece reaches the slope and the same surface, the position of the other end is the length of one end of the slope side of the 45 degree. To determine. This 値 is used as the measurement 値A. The difference between 25 cm and this measurement 値A is the extension length 値. The positive and negative surfaces of the five test pieces were measured, and the average enthalpy was used as the stretch length 其 of the test piece. The larger the length of the suspension, the harder the test piece, indicating that the test piece has poor drapability. The smaller the stretch length, the softer the test piece, indicating that the test piece has a good drapability. Example 1 -19- 200809022 (17) In the core component (fiber-forming resin component), IV = 〇.64dL/g, Tg = 70 °C, Tm = 2 5 6t: polyethylene terephthalate The ester (PET) is a high density polyethylene (HDPE) having MFR = 20 g/10 min and Tm = 131 ° C (Tg is less than zero) in the sheath component (thermal adhesive resin component). After melting each of the resins into 290 ° C and 250 ° C, a known core-sheath type composite fiber spinneret is used, and the weight ratio of the core component weight ratio to the sheath component weight ratio is 50 wt%: 50 wt%. After the composite fiber was formed, the yarn was spun under the conditions of a φ amount of 〇70 g/min/hole and a spinning speed of 1,150 m/min to obtain an unstretched yarn. After the unstretched filament is cold-extruded by 1.20 times, the cold-stretched yarn is immersed in an aqueous solution of an oil agent of 80 wt%:20 wt% of the potassium lauryl phosphate and the polyethylene oxide modified polyoxyalkylene. A mechanical crimping of 1.1/2 mm was given using a squeeze type crimping device (CRIMPER) with a picking box. Further, after the crimped yarn is released, it is subjected to a relaxation heat shrinkage treatment and a drying treatment at a temperature of 110 ° C higher than the glass transition temperature of the core component by 40 ° C, and then cut into a fiber length of Φ 5 1 mm. . The obtained heat-adhesive composite fiber has a single-filament fineness of 6.4 dtex, a strength of 0.76 cN/dtex, an elongation of 44%, a tensile stress of 100%, and a dry heat shrinkage of 0. 3 7 c N / dte X and 1 2 0 °C. Rate -2 · 6 %. The cotton web of the heat-adhesive composite fiber 100% has a shrinkage ratio of -7.5%, a non-woven strength of 15.1 kg/g, and a suspension length of 8.50 cm. Comparative Example 1 The undrawn yarn obtained in Example 1 was subjected to 2.5-fold extension in warm water at 70 ° C, and continued to be carried out in addition to the 1.2-fold extension in warm water of 90 ° C -20-200809022 (18). A composite fiber was produced under the conditions of Example 1. The obtained heat-adhesive composite fiber had a single yarn fineness of 2.6 dtex, a strength of 2.49 cN/dtex, an elongation of 37.1%, and a dry heat shrinkage ratio of 2.5% at 120 °C. Since the elongation of the heat-adhesive composite fiber is less than 100%, the tensile stress of 1% is not determined. The cotton web of the heat-adhesive composite fiber 100% has a cotton web area shrinkage of 5%, a non-woven fabric strength of 20.5 kg/g, and a suspension length of 値12.90 cm. Comparative Example 2 A composite fiber was produced under the same conditions as in Example 1 except that the stretching treatment was not carried out. The obtained heat-adhesive composite fiber has a single filament fineness of 6.47 dtex, a strength of 0 · 60 ° CN/dtex, an elongation of 4 6 0 · 3 %, 100% tensile stress of 0.37 cN/dtex, and 120 ° C dry. Heat shrinkage rate · 〇 · 7%. The cotton web of the heat-adhesive composite fiber of 100% has a shrinkage ratio of -1.45%, a non-woven strength of 14.5 kg/g, and a suspension length of 7.90 cm. • Example 2 A conjugate fiber was produced under the same conditions as in Example 1 except that the stretching ratio of cold stretching was 1.1 times. The obtained heat-adhesive composite fiber has a single-filament fineness of 6.41 dtex, a strength of 0.65 cN/dtex, an elongation of 424.1%, a tensile stress of 1·4 1 c N / dte X, and a temperature of 1 2 0 °C. The heat shrinkage rate was -1.9%. The cotton web area of the heat-adhesive composite fiber was reduced by -5.6%, the non-woven strength was 16.5 kg/g, and the stretched length was 8.10 cm. Example 3 - 21 - 200809022 A composite fiber was produced under the same conditions as in Example 1 except that the stretching ratio of the cold stretching was 1.30 times. The obtained heat-adhesive composite fiber had a single yarn fineness of 6.22 dtex, a strength of 0.72 cN/dtex, an elongation of 381.8%, a tensile stress of 100% 〇46 cN/dtex, and a dry heat shrinkage of -2.0% at 120 °C. 100% of the heat-adhesive composite fiber has a cotton web area shrinkage of -6.1%, a non-woven strength of 17.1 kg/g, and a suspension length of 8.90 cm. Comparative Example 3 has a stretch ratio of 1.4 times. A composite fiber was produced under the same conditions as in Example 1 except for the above. The obtained heat-adhesive composite fiber had a single yarn fineness of 6.14 dtex, a strength of 0.75 cN/dtex, an elongation of 346.8%, a 100% tensile stress of 0.53 cN/dtex, and a dry heat shrinkage of 120 °C of -0.6%. The cotton web of the heat-adhesive composite fiber has a shrinkage ratio of -1.8%, a non-woven strength of 18.4 kg/g, and a suspension length of 10.1 cm. (Example 4) A composite fiber was produced under the same conditions as in Example 1 except that the cold stretching was controlled while cooling in a water bath of water temperature of 20 t:. The obtained heat-adhesive composite fiber has a single-filament fineness of 6.52 dtex, a strength of 0,65 CN/dtex, an elongation of 459.3 %, a tensile stress of 100% 39.39 cN/dtex, and a dry heat shrinkage ratio of 120 ° C -3·2. %. The cotton web having a heat-adhesive composite fiber of 1%% has a cotton web area shrinkage of -9.5%, a non-woven fabric strength of 15.3 kg/g, and a suspension length of 8.1.13 cm. -22-200809022 Example 5 The relaxation heat shrinkage treatment and the heat treatment were carried out in a warm water bath at 95 ° C in an overfeed of 0.7 times, and the hot air drying thereafter was not carried out, and the same conditions as in Example 1 were carried out. Composite fiber. The obtained heat-adhesive composite fiber had a single yarn fineness of 6.58 dtex, a strength of 〇.68 cN/dtex, an elongation of 443.3%, a tensile stress of 100% 〇.41 cN/dtex, and a dry heat shrinkage of -3.9% at 120 °C. 100% of the heat-adhesive composite fiber has a cotton web area shrinkage ratio of -11.4%, a non-woven fabric strength of 14.9 kg/g, and a suspension length of 8.90 cm. Example 6 Core component (fiber-forming resin component) ) Polyethylene terephthalate (PET) with IV = 0.64dL/g, Tg = 70 °C, Tm = 2 5 6 °C, MFR II is used in the sheath component (thermal adhesive resin component) 40 g/10 min, Tm = 152 ° C, Tg = 4 3 ° C crystalline copolyester (using 20 mol% isophthalic acid, copolymerized tetramethyl glycol) 50 mol% polyterephthalic acid After the ethylene glycol ester was melted at 290 ° C and 25 5 ° C, the known core-sheath type composite fiber spinneret was used, and the core component weight ratio to the sheath component weight ratio was 50% by weight: 50% by weight. The weight ratio was changed to form a composite fiber, the discharge amount was 0 jlg/min/iL, and the spinning speed was 1 250 m/min, and spinning was performed to obtain an unstretched yarn. After extending the unstretched filament by 1.2 times, the cold-stretched strand is immersed in an aqueous solution of an oil agent of 80% by weight: 20% by weight of the potassium lauryl phosphate and the polyethylene oxide modified polyoxyalkylene. Thereafter, 11/25 mm mechanical crimping was imparted using an extrusion type crimping device with a box of -23-200809022 (21). Further, the crimped yarn was subjected to relaxation and subjected to drying and relaxation heat treatment in a hot air of 90 ° C, and then cut into a fiber length of 5 1 mm. The obtained heat-adhesive composite fiber had a single yarn fineness of 5.7 dtex, a strength of 0.94 cN/dtex, an elongation of 392%, a 100% tensile stress of 3535 cN/dtex, and a dry heat shrinkage of -3.8% at 120 °C. The shrinkage ratio of the cotton web area of the cotton web made of 100% of the heat-adhesive composite fiber (however, the heat adhesion temperature is changed to 180 ° C) is -1 1 · 2 %, the non-woven strength is 12.3 kg / g, and the stretch The hanging length is 8.30 cm. INDUSTRIAL APPLICABILITY The low-modulus self-stretching heat-adhesive composite fiber of the present invention uses PET as a fiber-forming resin component, and has a small spinning speed at the time of production, so that the yarn is broken at the time of spinning. Significantly less. Further, by using the conjugate fiber to produce a nonwoven fabric, a fluffy nonwoven fabric having high adhesion, high drape, and good touch can be obtained. -twenty four-