1288788 九、發明說明： 【發明所屬之技術領域】 本發明係關於以聚對苯二曱酸丙二醇酯(PTT)及聚對笨二甲 酸丁二醇酯（PBT)炼融紡絲所得到的自發捲縮性複合纖維及其製 造方法。 【先前技術】 具有伸縮彈性的織物一直為人們所喜愛，早期人們係使用天 然橡膠來生產伸縮織物，但後來逐漸以彈性纖維取代之。 由於人們對衣著的舒適性要求越來越高，具有伸縮性機能的 彈性纖維，因能充分展現人體天然的曲線美，並且可增加美感、 機能性、流行性，所以被廣泛地運用在各種織品，例如泳裝、滑 雪服、韻律服、運動服、緊身衣、絲襪等。彈性纖維產業近幾年 來發展相當迅速，市場上對於彈性纖維需求非常熱絡。 先前技術主要是使二種具有相異熔融黏度的聚合物從同一紡 絲孔吐出及經嫁融紡絲而得到並列型複合纖維。日本專利特開平 3 69647號提出當二種相異炼融黏度的聚合物吐出時，其高黏度 成分會有屈曲現象產生，若熔融黏度相差大時，其屈曲現象加劇， 纺絲作業性惡化。 複合纖維的自發捲縮性，係以製造並列型雙成分纖維時產生 的為主，其以二聚合體相異的極限黏度為基礎，因二聚合體具有 =同之收縮量而使纖維產生立體摺縐。自發捲縮性的先決條件乃 疋由二聚合體之收縮量、收縮程度及彈性模數的差異所產生一種 必然的潛在捲曲性。除了收縮差為必要條件外，該二成分間還必 須=有良好的黏著性，但不—定必然需使用不_聚合物。因為 收、:差亦可由定向、結晶度或相對黏度的差異而引發。然而一般 而a，同材質所能產生的收縮差異較小，不易產生高彈性訴求所 5 L:\menu\Pending-93\93159-發明專利說明書獻 1288788 需要的高收縮差。 【發明内容】 本發明之一目的是提供一種製造具有良好彈性、捲縮性及紡 絲性的複合纖維的方法。 本發明之另一目的是提供一種具有良好彈性、捲縮性及紡絲 性的複合纖維。 依據本發明之方法，係將聚對苯二甲酸丙二醇醋 (polytrimethylene terephthalate，以下稱 PTT)及聚對苯二甲酸丁二 醇酯(polybutylene terephthalate，以下稱PBT)之二相異的聚合體 成分，以並列型（side-by-side)複合方式紡絲，以得到並列型複合 纖維’其中PTT為較高極限黏度成分，其極限黏度(intrinsic Viscosity; IV)在 0·80 dL/g 至 1·20 dL/g 之間，PBT 為較低極限黏 度成分，其極限黏度在0.58 dL/g至0·84 dL/g之間，PTT及PBT 之重量比在30: 70至70: 30的範圍，且二成分之極限黏度差(△ IV) -0.15 dL/g。此複合纖維為具有彈性指標(Crimp Index ; CI) 達40以上的自發捲縮性複合纖維，其具有良好彈性、捲縮性及紡 絲性。 本發明所使用之聚酯聚合體，在出紡口之接合面佳，屈曲現 象極輕微，不影響紡絲作業性。 本發明亦關於並列型複合纖維，其包含聚對苯二甲酸丙二醇 酯(PTT)及聚對苯二甲酸丁二醇酯(PBT)二種聚合體，PTT及PBT 之重量比在30 : 70至70 : 30的範圍，PTT之極限黏度(Intrinsic Viscosity; IV)在 0·80 dL/g 至 1·20 dL/g 之間，PBT 之極限黏度在 0·58 dL/g至0.84 dL/g之間，且PTT之極限黏度大於PBT的極限 黏度，二者之極限黏度差異(Δίν) -0·15 dL/g。此複合紡絲，除 具有PTT、PBT本身之彈性外，再加上收縮後由絲長差所產生外 6 L:\menu\Pending-93\93159-發明專利說明書.doc 1288788 觀捲曲之彈性達雙重效果，因此具有相當優良之彈性。 【實施方式】 本發明之捲縮性聚酯纖維，係將並列型（side_by-side)複合化之 纖維延伸熱處理後所產生外觀捲曲之纖維。 根據本發明之捲縮性聚酯纖維，其中聚對苯二甲酸丙二醇酯 (PTT)主要包含對苯二甲酸與丙二醇之重複單位，及聚對苯二甲酸 丁二醇酯(PBT)主要包含對苯二甲酸與丁二醇之重複單位。 又，根據本發明，聚對苯二甲酸丙二醇酯及聚對苯二甲酸丁 二醇酯視需要可與第3成份共聚，該成份可選自脂族二羧酸、芳 族二羧酸、脂族二元醇或苯磺酸金屬鹽等成份，較佳為選自苯二 甲酸、己二酸、丁二醇、戊二醇、己二醇或苯磺酸金屬鹽。 本發明中，聚酯纖維視需要可添加各種添加劑，包括消光劑、 熱安定劑、消泡劑、抗氧化劑、紫外線吸收劑、抗菌劑、難燃劑、 導電劑、顏料等添加劑。 本發明所用聚酯成分中，ΡΤΤ的極限黏度(Intrinsic Visc〇sity; IV)在 0·80 dL/g 至 1·20 dL/g 較佳，在 〇·84 dL/g 至 1.00 dL/g 時 更佳。而PBT的極限黏度在〇·58 dL/g至〇料dL/g較佳，在〇以 dL/g至0.78 dL/g時更佳。依據本發明，ρττ之極限黏度必須大 於ΡΒΤ之極限黏度，而且ΡΤΤ與ρΒΤ二者的極限黏度差Διν ^ 0·15 dL/g 為佳，-〇·25 dL/g 更佳。 兩聚合體成分的黏度差使彈性指標(CrimpIndex;CI)提高。當 △IVgO.15 dL/g可得到良好立體捲縮，當b dL/g以上更 佳而Δίν小於0·15 dL/g以下時，彈性指標偏低且彈性略差。 ρττ之極限黏度小於0·80 dL/g時，彈性指標不佳。當 之極限黏度大於I·2 dL/g時，賴指標趨於平穩，流動性變差， 紡絲作業困難。 7 LiXmemAPendingW^W-發明專利說明書.doc ύ *i ' Η .''，::、1288788 專利申請案第93118389號 ROC Patent Appln.No. 93118389 修正後無劃線冬中文說明書替換頁-附件(三） Amended pages in Chinese Specification- Enel. (IIP (良琴93年11月 Z曰送呈)~ (Submitted on November 2004) PBT之極限黏度小於0.58 dL/g時，會產生切粒方面問題生產 不易，且溶融黏度偏低，紡絲作業性困難。當PBT之極限黏度大 於0.84 dL/g時，彈性指標不佳。 複合纖維中PT丁和PBT重量比在30 : 70至70 ·· 30可得到良 好的立體捲縮複合纖維，重量比在4〇 : 60至60 : 40可得較佳的 立體捲縮效果，而重量比在45 : 55至55 : 45時可得到最佳立體 捲縮效果。 圖1顯示有關本發明紡絲程序所用設備之示意圖。ΡΤΊΓ及PBT 經由溶融複合紡絲機之紡絲箱（1)之紡絲孔吐出合流形成並列型 (side-by-side)熔融纖維(2) ’溶融纖維(2)經由冷卻裝置(3)的冷卻 氣體固化後，經整理劑施加裝置（4)賦與絲條整理劑（fmish agent)，經過引取羅拉(5)、（6)後，以捲取裝置(7)捲取成絲餅(8)。 圖2顯示本發明方法中延伸程序所用設備之示意圖，將圖工 紡絲程序所產生之絲餅(8)中之複合纖維pi)拉出並送經延伸羅拉 (9)加以延伸，續經熱板(10)予以定型、冷卻羅拉（11)予以冷卻、交 織裝置（12)予以集束及捲取裝置（13)予以捲取成絲管(未示出）。 本發明之複合纖維，其斷面形狀可例如圖3之(A)、（B)、（c) 等所示形狀。 本發明採用極限黏度不同之PTT、PBT聚合體，以熔融複合 紡絲機，將PTT及PBT由紡絲孔吐出合流形成並列型複合纖維， 減少屈曲現象，增加紡絲安定性。紡絲溫度通常在24〇〜以❹亡範 圍較佳。紡出之纖維經冷卻固化、賦與油劑後，以2500〜4500 m/min速度捲取。此纖維再經延伸機連續熱延伸處理，而得到本 發明之複合纖維。 延伸倍率需適宜選定，引取後殘留伸度為15〜4〇%最佳，其 捲縮性能較佳。殘留伸度過低時，容易產生單絲斷裂、操作性的 問題。 8 1—Ρεη(ϋι^93\93159-發明專利說明書呢丨丨-接丨d〇c 8卿正！ 本發明之方法所得到之自發捲縮性複合纖維，其彈性指標 :隹上’較目前市㈣品高出❹’其外觀捲轉久性也較 :二，|使用本發明之複合纖維所製成之編織 逄鬆感與良好的彈性。 「 下文中將以非限舰的實施例來進—步說明本發明。首先對 實施例中物性測定方法簡單說明。 彈性指標(Crimp Index; CI): 將複合纖維樣品垂直懸吊(De x 〇〇6)公克（即每！丹尼爾給予 6 a克之荷重，De代表纖維之丹尼爾數)之荷重並放入1⑻。◦水 中煮15分鐘後，取出冷卻至室溫，之後去除該荷重，再給予(DeX 〇·〇2)公克之荷重，讀取絲長為Li，然後去除該荷重，再給予(Dj 4)公克之荷重，讀取絲長為L2。計算方式： CI% = L2-L1 -X 1001288788 IX. Description of the invention: [Technical field to which the invention pertains] The present invention relates to spontaneous ablation by poly(p-phenylene terephthalate) (PTT) and poly(p-butylene dicarboxylate) (PBT). Crimped composite fiber and a method of producing the same. [Prior Art] Fabrics having elasticity and elasticity have been favored for a long time. In the early days, natural rubber was used to produce stretch fabrics, but it was gradually replaced by elastic fibers. Due to the increasing demands on the comfort of clothing, elastic fibers with stretchable functions are widely used in various fabrics because they can fully express the natural curvilinear beauty of the human body and increase aesthetics, function and popularity. For example, swimwear, ski wear, rhythm suits, sportswear, tights, stockings, etc. The elastic fiber industry has developed quite rapidly in recent years, and the demand for elastic fibers in the market is very hot. The prior art mainly consists of two kinds of polymers having different melt viscosities which are discharged from the same spinning hole and are subjected to marry spinning to obtain a side-by-side type composite fiber. Japanese Patent Laid-Open No. Hei 3 69647 proposes that when two polymers of different smelting viscosities are discharged, the high-viscosity component may have a buckling phenomenon. If the melt viscosity differs greatly, the buckling phenomenon is aggravated and the spinning workability is deteriorated. The spontaneous crimping property of the composite fiber is mainly produced when the parallel type bicomponent fiber is produced, and the fiber is three-dimensionally based on the difference in viscosity of the dimer. Depreciation. A prerequisite for spontaneous curling is an inevitable potential curling property resulting from the difference in shrinkage, shrinkage, and modulus of elasticity of the two polymers. In addition to the difference in shrinkage, it is necessary to have good adhesion between the two components, but it is not necessary to use a non-polymer. Because the acceptance: difference can also be caused by the difference in orientation, crystallinity or relative viscosity. However, in general, a, the difference in shrinkage that can be produced by the same material is small, and it is not easy to produce a high elasticity appeal. 5 L:\menu\Pending-93\93159-Inventive Patent Specification 1288788 High shrinkage required. SUMMARY OF THE INVENTION An object of the present invention is to provide a process for producing a composite fiber having good elasticity, crimping property and spinnability. Another object of the present invention is to provide a composite fiber having good elasticity, crimping property and spinnability. According to the method of the present invention, a polydimethylene terephthalate (hereinafter referred to as PTT) and a polybutylene terephthalate (hereinafter referred to as PBT) are two different polymer components. Spinning in a side-by-side composite manner to obtain a side-by-side composite fiber in which PTT is a higher ultimate viscosity component, and its intrinsic Viscosity (IV) is from 0.80 dL/g to 1·. Between 20 dL/g, PBT is a lower ultimate viscosity component with an ultimate viscosity of 0.58 dL/g to 0.84 dL/g, and a weight ratio of PTT to PBT of 30:70 to 70:30. And the difference in viscosity of the two components (△ IV) -0.15 dL / g. The composite fiber is a self-compression crimped composite fiber having a modulus of elasticity (Crimp Index; CI) of 40 or more, which has good elasticity, crimping property, and spinnability. The polyester polymer used in the present invention is excellent in the joint surface of the spun yarn, and the buckling phenomenon is extremely slight, and does not affect the spinning workability. The invention also relates to a side-by-side type composite fiber comprising two polymers of polytrimethylene terephthalate (PTT) and polybutylene terephthalate (PBT), and the weight ratio of PTT to PBT is 30:70 to In the range of 70:30, the ultimate viscosity of PTT (Intrinsic Viscosity; IV) is between 0·80 dL/g and 1·20 dL/g, and the ultimate viscosity of PBT is between 0·58 dL/g and 0.84 dL/g. The ultimate viscosity of PTT is greater than the ultimate viscosity of PBT, and the difference in viscosity of the two is (Δίν) -0·15 dL/g. This composite spinning, in addition to the flexibility of PTT and PBT itself, plus the shrinkage caused by the length difference of the wire 6 L:\menu\Pending-93\93159-Invention patent specification.doc 1288788 Double effect, so it has quite good elasticity. [Embodiment] The crimped polyester fiber of the present invention is a fiber obtained by stretching a side-by-side composite fiber after heat treatment. The crimped polyester fiber according to the present invention, wherein the polytrimethylene terephthalate (PTT) mainly comprises a repeating unit of terephthalic acid and propylene glycol, and the polybutylene terephthalate (PBT) mainly comprises a pair Repeating unit of phthalic acid and butanediol. Further, according to the present invention, polytrimethylene terephthalate and polybutylene terephthalate may be copolymerized with the third component as needed, and the component may be selected from the group consisting of aliphatic dicarboxylic acids, aromatic dicarboxylic acids, and fats. The component such as a diol or a metal benzenesulfonate is preferably selected from the group consisting of phthalic acid, adipic acid, butylene glycol, pentanediol, hexanediol or a metal benzenesulfonate. In the present invention, the polyester fiber may be added with various additives as needed, including a matting agent, a thermal stabilizer, an antifoaming agent, an antioxidant, an ultraviolet absorber, an antibacterial agent, a flame retardant, a conductive agent, a pigment, and the like. In the polyester component used in the present invention, the ultimate viscosity (Intrinsic Visc〇sity; IV) of yttrium is preferably from 0.80 dL/g to 1.20 dL/g, and from 〇·84 dL/g to 1.00 dL/g. Better. The PBT has a viscosity of 〇·58 dL/g to dL/g, preferably ddL/g to 0.78 dL/g. According to the present invention, the ultimate viscosity of ρττ must be greater than the ultimate viscosity of ΡΒΤ, and the ultimate viscosity difference Διν ^ 0·15 dL/g of both ΡΤΤ and ρ 为 is better, and 〇·25 dL/g is better. The difference in viscosity between the two polymer components increases the elastic index (CrimpIndex; CI). When ΔIVgO.15 dL/g can obtain good three-dimensional crimping, when b dL/g or more is better and Δίν is less than 0·15 dL/g, the elastic index is low and the elasticity is slightly poor. When the ultimate viscosity of ρττ is less than 0·80 dL/g, the elasticity index is not good. When the ultimate viscosity is greater than I·2 dL/g, the Lai index tends to be stable, the fluidity is deteriorated, and the spinning operation is difficult. 7 LiXmemAPendingW^W-Invention Patent Specification.doc ύ *i ' Η .'',::,1288788 Patent Application No. 93118389 ROC Patent Appln.No. 93118389 Corrected no scribe winter Chinese manual replacement page - attachment (three Amended pages in Chinese Specification- Enel. (IIP) (Submitted on November 2004) When the ultimate viscosity of PBT is less than 0.58 dL/g, the problem of pelletizing is not easy to produce, and The melt viscosity is low and the spinning operation is difficult. When the ultimate viscosity of PBT is more than 0.84 dL/g, the elastic index is not good. The weight ratio of PT and PBT in composite fiber is 30:70 to 70 ·· 30 The three-dimensional crimping composite fiber has a weight ratio of 4〇: 60 to 60: 40 to obtain a better three-dimensional crimping effect, and an optimum three-dimensional crimping effect at a weight ratio of 45:55 to 55:45. A schematic view showing the apparatus used in the spinning process of the present invention. The crucible and the PBT are combined to form a side-by-side molten fiber (2) through the spinning orifice of the spinning box (1) of the melt compound spinning machine. The molten fiber (2) is solidified by the cooling gas of the cooling device (3) Thereafter, the finishing agent applying device (4) is given a fmish agent, and after passing through the drawing rollers (5) and (6), the winding device (7) is taken up to form a cake (8). 2 is a schematic view showing the apparatus used in the extension process of the method of the present invention, the composite fiber pi) in the cake (8) produced by the drawing spinning process is pulled out and sent through the extension roller (9) for extension, and the hot plate is continued. (10) The cooling roller (11) is cooled, the interlacing device (12) is bundled, and the winding device (13) is wound into a wire tube (not shown). The cross-sectional shape of the conjugate fiber of the present invention can be, for example, the shape shown in Figs. 3(A), (B), (c) and the like. The invention adopts PTT and PBT aggregates with different ultimate viscosity, and combines PTT and PBT from the spinning holes to form a side-by-side type composite fiber by a melt-composite spinning machine, thereby reducing buckling phenomenon and increasing spinning stability. The spinning temperature is usually in the range of 24 Torr to the extent of the dying. The spun fiber is cooled and solidified, and after being oiled, it is taken up at a speed of 2500 to 4500 m/min. The fiber is then continuously thermally stretched by an extension machine to obtain a composite fiber of the present invention. The stretching ratio should be appropriately selected, and the residual elongation after drawing is preferably 15 to 4%, and the crimping performance is better. When the residual elongation is too low, the problem of breakage of the monofilament and operability is liable to occur. 8 1—Ρεη(ϋι^93\93159- Invention patent specification 丨丨-接丨d〇c 8Qingzheng! The spontaneous crimping composite fiber obtained by the method of the present invention, its elasticity index: 隹上' The city (4) is higher than the product's appearance. The appearance of the product is also longer than the following: Second, the use of the composite fiber of the present invention makes the weaving feel and good elasticity. "In the following, the embodiment of the non-limited ship will be used. The present invention will be further described. First, the physical property measurement method in the examples will be briefly described. Elasticity index (Crimp Index; CI): The composite fiber sample is vertically suspended (De x 〇〇 6) g (ie, each! The weight of the gram load, De represents the denier of the fiber) and put it into 1 (8). After boiling for 15 minutes in water, take it out and cool it to room temperature, then remove the load, and then give (DeX 〇·〇2) gram load, read The filament length is Li, then the load is removed, and the load of (Dj 4) gram is given, and the length of the read filament is L2. Calculation method: CI% = L2-L1 -X 100
Li 【實施例1〜5，比較例1〜4】 PTT與PBT於不同之極限黏度，重量比50 : 50情況下溶融 擠製紡絲，使用24孔的紡絲頭，紡溫26(TC，絲條經冷卻、固化 並賦予油劑，再以3000 m/min速度捲取。經延伸倍率1.6，溫度 80°C延伸熱處理後，得到l〇〇d/24f(即丹尼爾數為1〇〇，有24根單 纖維)的捲縮型複合纖維。複合纖維的彈性指標、外觀捲曲、與紡 絲性列於表1。 9 L:\menu\Pending-93\93159-發明專利說明書-9311-接 l.doc 1288788 表1Li [Examples 1 to 5, Comparative Examples 1 to 4] PTT and PBT were melted and extruded at different ultimate viscosity, weight ratio of 50:50, using a 24-hole spinning head, and a spinning temperature of 26 (TC, The thread is cooled, solidified and oiled, and then taken up at a speed of 3000 m/min. After extending heat treatment at a stretching ratio of 1.6 and a temperature of 80 ° C, l〇〇d/24f is obtained (ie, the denier number is 1 〇〇, There are 24 single fiber) crimped composite fibers. The elastic index, appearance curl, and spinnability of the composite fiber are listed in Table 1. 9 L:\menu\Pending-93\93159-Invention patent specification-9311- L.doc 1288788 Table 1
符號說明：◎:佳 由表1可知’本發明之複合纖維中pTT的極限黏度比PBT的 極限黏度夕過（U5dL/g時，可得到良好立體捲縮，彈性指標高達 40以上，外觀捲曲持久性也較佳。當以上更佳。 而AIV 士】、於〇·ΐ5 dL/g以下時，《pTT的極限黏度比pBT的極限 黏度小日彳’彈性指標偏低且彈性略差。又，ρττ之極限黏度小於 〇.8〇dL/g k，彈性指標不佳。當PTT之極限黏度大於i.2dL/g時， 彈性指標趨於平穩，流動性變差，紡絲作業困難。 PBT之極限黏度小於〇·58 dL/g時，會產生切粒方面問題生產 不易，且熔融黏度偏低，紡絲作業性困難。當ρΒτ之極限黏度大 於0.84 dL/g時，彈性指標不佳。 10 L:\menu\Pending-93\93159-發明專利說明書.doc 1288788 【實施例6】 使用極限黏度為0.90 dL/g的PTT與極限黏度為〇·6〇 dL/g的 PBT，重量比50: 50,使用24孔的紡絲頭，以紡溫施。c溶融纺 絲’絲條經冷卻、固化並賦予油劑，經延伸倍率15、延伸定型严 度140°C，並以4500 m/min速度直接纺絲製程，得到75d/24f(即 丹尼爾數為75，有24根單纖維)捲縮型複合纖維，其外觀具有優 良之立體捲縮型態且彈性指標CI=45。 【實施例7】 PTT的極限黏度為〇·9〇 dL/g與PBT的極限黏度為〇 6〇 dL/g, 重置複合比例50 · 50，使用24孔的紡絲頭，以紡溫26〇ι熔融紡 絲，絲條經冷卻、固化並賦予油劑，以3〇〇〇 m/min速度捲取。再 經延伸倍率1.6假撚加工處理，得到75,2<(即丹尼爾數為乃，有 24根單纖維）的捲縮型複合纖維，其外觀具有優良之立體捲縮型 態且彈性指標CI=65。 為了忒明之目的，本發明已經詳述於上，然而應瞭解上述細 節僅用以說明之目的，且本發明得由熟悉本技藝之人士施以變 化，皆不脫本發明之精神及範圍，本發明僅受限於如附申請專利 範圍。 【圖式簡單說明j 圖1為紡絲程序設備示意圖； 圖2為纖維延伸程序設備示意圖；及 圖3為本發明複合纖維之斷面圖。 11 L:\menu\Pending-93\93159-發明專利說明書.doc 1288788 【主要元件符號說明】 1 ： 紡絲箱 2 ： 絲條(纖維） 3 ： 冷卻裝置 4 ·· 油劑施加裝置 5 ： 引取羅拉 6 ： 引取羅拉 7 ： 捲取裝置 8 ： 絲餅 9 ·· 延伸羅拉 ίο:熱板 11 :冷卻羅拉 12 :交織裝置 13 :捲取裝置 81:複合纖維 12 L:\menu\Pending-93\93159-發明專利說明書.docDESCRIPTION OF SYMBOLS: ◎: According to Table 1, it can be seen that the ultimate viscosity of pTT in the composite fiber of the present invention is longer than the ultimate viscosity of PBT (U5dL/g, good three-dimensional crimping can be obtained, the elastic index is as high as 40 or more, and the appearance is curled for a long time. The sex is also better. When the above is better. When AIV is less than 5 dL/g, the ultimate viscosity of pTT is lower than the ultimate viscosity of pBT, and the elasticity index is lower and the elasticity is slightly worse. The ultimate viscosity of ρττ is less than 〇.8〇dL/gk, and the elastic index is not good. When the ultimate viscosity of PTT is greater than i.2dL/g, the elastic index tends to be stable, the fluidity is deteriorated, and the spinning operation is difficult. When the viscosity is less than 〇·58 dL/g, the problem of pelletizing is not easy to produce, and the melt viscosity is low, and the spinning operation is difficult. When the ultimate viscosity of ρΒτ is more than 0.84 dL/g, the elastic index is not good. :\menu\Pending-93\93159-Invention patent specification.doc 1288788 [Example 6] PTT with an ultimate viscosity of 0.90 dL/g and PBT with an ultimate viscosity of 〇·6〇dL/g, weight ratio 50: 50 , using a 24-hole spinneret to spin the temperature. c melt spinning 'filaments through the cold , curing and imparting an oil agent, through a stretching ratio of 15, elongation and strictness of 140 ° C, and direct spinning process at a speed of 4500 m / min, to obtain a 75d / 24f (ie, a Daniel number of 75, 24 single fiber) volume The shrinkage type composite fiber has an excellent three-dimensional crimped appearance and an elastic index CI=45. [Example 7] The ultimate viscosity of PTT is 〇·9〇dL/g and the ultimate viscosity of PBT is 〇6〇dL/ g, reset composite ratio 50 · 50, using a 24-hole spinning head, melt spinning at a spinning temperature of 26 〇, the yarn is cooled, solidified and oiled, and wound at a speed of 3 〇〇〇 m / min After the elongation ratio of 1.6 false twist processing, 75, 2 < (ie, the Daniel number is 24, single fiber) crimped composite fiber, the appearance of which has an excellent three-dimensional crimp type and elastic index CI The present invention has been described in detail for the purposes of illustration and description of the invention. The scope of the present invention is limited only by the scope of the patent application. [Simple description of the figure j Figure 1 Figure 2 is a schematic view of a fiber extension program; and Figure 3 is a sectional view of the composite fiber of the present invention. 11 L:\menu\Pending-93\93159-Invention Patent Specification.doc 1288788 [Main components DESCRIPTION OF SYMBOLS 1 : Spinning box 2 : Filament (fiber) 3 : Cooling device 4 · Oil application device 5 : Extraction roller 6 : Extraction roller 7 : Winding device 8 : Wire cake 9 · · Extension roller ίο: Hot plate 11 : Cooling roller 12 : Interlacing device 13 : Winding device 81 : Composite fiber 12 L: \menu\Pending-93\93159 - Invention patent specification.