JP2004277931A - Polylactic acid fiber and fibrous structure using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide polylactic acid fiber excellent in wear resistance and hydrolysis resistance, slight in yellowing tendency in itself, and also good in color developability when dyed. <P>SOLUTION: The polylactic acid fiber comprises a fatty acid bisamide component and/or alkyl-substituted type fatty acid monoamide component, wherein the terminal carboxy groups are blocked with a carbodiimide compound. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【０１１１】
比較例１
Ｐ１のみ（ポリ乳酸のみ）を使用して実施例１と同様にして、８４ｄｔｅｘ、３６フィラメントの延伸糸を得た。パック圧は終始安定しており、口金直下での発煙も少なかったが、糸切れ、毛羽が発生し、紡糸性はあまり良くなかった。また、延伸性も糸切れや毛羽の発生によりあまり良くなかった。
【０１１２】
得られた繊維は、ｂ^＊値は０．５と黄味が極めて少なく良好な色調であったが、カルボキシル基末端濃度は４０当量／ｔｏｎであり、熱水処理後のη_ｒ保持率および強度保持率は非常に悪く、耐加水分解性に劣ったものであった。
【０１１３】
また、得られた染色布帛は、Ｌ^＊値１０．２、Ｃ^＊値１．４とまずまずの黒発色性を示したが、布帛の引裂強力は２５０ｃＮと極めて悪かった。この布帛の風合いは、ポリ乳酸繊維特有の機械的なきしみ感があり、実施例１に劣るものであった。
【０１１４】
さらに、これの摩擦堅牢度を測定したところ、１級と耐摩耗性は劣悪であった。また、摩擦試験後の布帛の表面をＳＥＭにて観察した結果、糸の摩耗が著しいものであった（図２）。また、この染色布帛を用い、工業裁断、工業縫製を行ったが、裁断時に布帛裁断部での融着が激しく、またミシン針の汚れも著しく、劣悪な工程通過性であった。さらに、これを用いシャツを作製し１ヶ月間着用した耐久テストを行ったが、毛羽立ちや白化、テカリが著しく、劣悪な製品耐久性であった。
【０１１５】
比較例２
重量比でＰ１：Ｐ４＝７５：２５となるようにチップブレンド（ＳＡは１ｗｔ％）した以外は実施例１と同様にして、８４ｄｔｅｘ、３６フィラメントの延伸糸を得た。パック圧は終始安定していたが、口金直下での発煙が多く、糸切れ、毛羽が発生し、紡糸性はあまり良くなかった。また、延伸性も糸切れや毛羽の発生によりあまり良くなかった。
【０１１６】
得られた繊維は、ｂ^＊値は４．２とまずまずの色調であったが、カルボキシル基末端濃度は４３当量／ｔｏｎであり、熱水処理後のη_ｒ保持率および強度保持率は非常に悪く、耐加水分解性に劣ったものであった。
【０１１７】
また、得られた染色布帛は、Ｌ^＊値１０．０、Ｃ^＊値１．４とまずまずの黒発色性を示したが、布帛の引裂強力は２６０ｃＮと極めて悪かった。この布帛の風合いは、ポリ乳酸繊維特有の機械的なきしみ感があり、実施例１に劣るものであった。
【０１１８】
さらに、これの摩擦堅牢度を測定したところ、１級と耐摩耗性は劣悪であった。また、この染色布帛を用い、工業裁断、工業縫製を行ったが、裁断時に布帛裁断部での融着が激しく、またミシン針の汚れも著しく、劣悪な工程通過性であった。さらに、これを用いシャツを作製し１ヶ月間着用した耐久テストを行ったが、毛羽立ちや白化、テカリが著しく、劣悪な製品耐久性であった。
【０１１９】
なお、ＴＧ（熱重量測定）から、ＳＡの加熱による減量率を求めたところ、２５０℃で４．１％も重量減少することがわかった。これに対して、脂肪酸ビスアミドであるＥＢＡの場合は、２５０℃で０．５％しか重量減少せず、脂肪酸モノアミドに比べて脂肪酸ビスアミドは、耐熱性が良く、昇華しにくいことがわかった。
【０１２０】
比較例３
染色方法１（染色温度１１０℃）に変更すること以外は比較例２と同様にして、８４ｄｔｅｘ、３６フィラメントの延伸糸からなる染色布帛を得た。
【０１２１】
得られた染色布帛は、引裂強力は６７０ｃＮとまずまずの値であったが、Ｌ^＊値１６．０、Ｃ^＊値１．６と黒発色性に劣るものであった。
【０１２２】
さらに、これの摩擦堅牢度を測定したところ、１級と耐摩耗性は劣悪であった。
【０１２３】
また、この染色布帛を用い、工業裁断、工業縫製を行ったが、裁断時に布帛裁断部での融着が激しく、またミシン針の汚れも著しく、劣悪な工程通過性であった。さらに、これを用いシャツを作製し１ヶ月間着用した耐久テストを行ったが、毛羽立ちや白化、テカリが著しく、劣悪な製品耐久性であった。
【０１２４】
比較例４
重量比でＰ１：Ｐ２＝７５：２５となるようにチップブレンド（ＥＢＡは１ｗｔ％）し、染色方法３（染色温度１２０℃）を用いた以外は実施例１と同様にして、８４ｄｔｅｘ、３６フィラメントの延伸糸を得た。パック圧は終始安定しており、口金直下での発煙も少なかった。また、糸切れ、毛羽の発生は見られず、紡糸性は極めて良好であった。また、延伸性も単巻等もなく良好であり、ガイド類への毛羽の付着も見られなかった。
【０１２５】
得られた繊維は、ｂ^＊値は１．２と黄味が少なく良好な色調であったが、カルボキシル基末端濃度は４１当量／ｔｏｎであり、熱水処理後のη_ｒ保持率および強度保持率は非常に悪く、耐加水分解性に劣ったものであった。
【０１２６】
また、得られた染色布帛は、しなやかでソフトでありながら、ポリ乳酸繊維特有の機械的なきしみ感が少ない優れた風合いを示し、Ｌ^＊値３３．８、Ｃ^＊値４１．０とまずまずの青色の鮮明色発色性を示したが、布帛の引裂強力は３００ｃＮと極めて悪かった。
【０１２７】
この布帛の摩擦堅牢度については、４級と耐摩耗性に優れたものであった。さらに、この染色布帛を用い、工業裁断、工業縫製を行ったが、裁断時の布帛裁断部での融着が無く、ミシン針の汚れも微少なものであり、優れた工程通過性を示した。さらに、これを用いシャツを作製し１ヶ月間着用した耐久テストを行ったが、毛羽立ちや白化、テカリも無く、優れた製品耐久性を示した。
【０１２８】
比較例５
重量比でＰ１：Ｐ５＝８８：１２となるようにチップブレンド（ＰＣＩのカルボジイミド基量はポリ乳酸のカルボキシル基末端量に対して１．２倍当量）し、紡糸温度を２４５℃に変更し、染色方法３（染色温度１２０℃）を用いた以外は実施例１と同様にして、８４ｄｔｅｘ、３６フィラメントの延伸糸を得た。紡糸温度２４５℃と高温条件にも関わらず、パック圧は経時的に上昇し、終始不安定であった。また口金直下ではポリ乳酸およびＰＣＩの熱分解に伴う発煙が多量に発生した。また、糸切れ、毛羽が発生し、紡糸性はあまり良くなかった。さらに、延伸性も糸切れや毛羽の発生によりあまり良くなかった。
【０１２９】
得られた繊維は、カルボキシル基末端濃度は検出限界以下の５当量／ｔｏｎ以下であり、熱水処理後のη_ｒ保持率および強度保持率は良好で、耐加水分解性に優れるものであったが、ｂ^＊値が８．９と黄味が多く劣悪な色調であった。
【０１３０】
また、得られた染色布帛は、Ｌ^＊値３１．０、Ｃ^＊値３３．０とまずまずの鮮明色発色性を示したが、繊維自体の黄色着色の影響で少し黄味がかった色相となった。また、引裂強力は７３０ｃＮと良好であったが、この布帛の風合いは、ポリ乳酸繊維特有の機械的なきしみ感があり、実施例１に劣るものであった。
【０１３１】
さらに、これの摩擦堅牢度を測定したところ、１級と耐摩耗性は劣悪であった。また、この染色布帛を用い、工業裁断、工業縫製を行ったが、裁断時に布帛裁断部での融着が激しく、またミシン針の汚れも著しく、劣悪な工程通過性であった。さらに、これを用いシャツを作製し１ヶ月間着用した耐久テストを行ったが、毛羽立ちや白化、テカリが著しく、劣悪な製品耐久性であった。
【０１３２】
比較例６
重量比でＰ１：Ｐ６＝８５：１５となるようにチップブレンド（ＴＩＣのカルボジイミド基量はポリ乳酸のカルボキシル基末端量に対して１．２倍当量）し、紡糸温度を２３５℃に変更し、染色方法２（染色温度１１０℃）に変更したこと以外は実施例１と同様にして、８４ｄｔｅｘ、３６フィラメントの延伸糸を得た。紡糸温度２３５℃と高温条件にも関わらず、パック圧は経時的に上昇し、終始不安定であった。また口金直下ではポリ乳酸およびＴＩＣの熱分解に伴う発煙が多量に発生した。また、糸切れ、毛羽が発生し、紡糸性はあまり良くなかった。さらに、延伸性も糸切れや毛羽の発生によりあまり良くなかった。
【０１３３】
得られた繊維は、カルボキシル基末端濃度は検出限界以下の５当量／ｔｏｎ以下であり、熱水処理後のη_ｒ保持率および強度保持率は良好で、耐加水分解性に優れるものであったが、ｂ^＊値が７．０と黄味が多く劣悪な色調であった。
【０１３４】
また、得られた染色布帛は、Ｌ^＊値４２．３、Ｃ^＊値３３．４とまずまずの赤色の鮮明色発色性を示したが、繊維自体の黄色着色の影響で少し黄味がかった色相となった。また、引裂強力は７７０ｃＮと良好であったが、この布帛の風合いは、ポリ乳酸繊維特有の機械的なきしみ感があり、実施例１に劣るものであった。
【０１３５】
さらに、これの摩擦堅牢度を測定したところ、１級と耐摩耗性は劣悪であった。また、この染色布帛を用い、工業裁断、工業縫製を行ったが、裁断時に布帛裁断部での融着が激しく、またミシン針の汚れも著しく、劣悪な工程通過性であった。さらに、これを用いシャツを作製し１ヶ月間着用した耐久テストを行ったが、毛羽立ちや白化、テカリが著しく、劣悪な製品耐久性であった。
【０１３６】
【表２】

【０１３７】
【発明の効果】
本発明によれば、耐摩耗性および耐加水分解性に優れ、且つ繊維自体の黄色着色が少なく、さらには染色時の発色性に優れたポリ乳酸繊維を提供することができ、ポリ乳酸繊維の用途展開幅を大きく拡大することができる。
【図面の簡単な説明】
【図１】本発明のポリ乳酸繊維の摩耗状態を示す図である。
【図２】従来のポリ乳酸繊維の摩耗状態を示す図である。
【図３】紡糸装置を示す図である。
【図４】延伸装置を示す図である。
【符号の説明】
１：ホッパー
２：押し出し混練機（エクストルーダー）
３：スピンブロック
４：紡糸パック
５：口金
６：チムニー
７：糸条
８：集束給油ガイド
９：交絡ガイド
１０：第１引き取りローラー
１１：第２引き取りローラー
１２：巻取糸
１３：未延伸糸
１４：フィードローラー
１５：第１ホットローラー
１６：第２ホットローラー
１７：コールドローラー
１８：延伸糸[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a polylactic acid fiber which is excellent in abrasion resistance and hydrolysis resistance, has little yellow coloring of the fiber itself, and further has excellent coloring property at the time of dyeing.
[0002]
[Prior art]
In recent years, with increasing awareness of the environment on a global scale, there is a concern about global warming caused by mass consumption of petroleum resources and depletion of petroleum resources accompanying mass consumption. From such a background, there is a long-felt need for a natural-circulation-type environment-friendly material that is made of plant-derived materials (biomass) and that eventually decomposes into water and carbon dioxide in the natural environment after use.
[0003]
However, biodegradable polymers utilizing biomass have heretofore been problematic in that their production costs are high, their mechanical properties and heat resistance are low, and they have not been used for general-purpose plastics. As a biodegradable polymer utilizing biomass that can solve these problems, polylactic acid, which is a kind of aliphatic polyester, is currently receiving the most attention. Polylactic acid is a polymer made from lactic acid obtained by fermenting starch extracted from plants, and has the best balance among mechanical properties, heat resistance and cost among biodegradable polymers using biomass. Development of resin products, fibers, films, sheets, and the like utilizing this is being carried out at a rapid pace.
[0004]
Agricultural materials and civil engineering materials that utilize biodegradability are leading in the development of polylactic acid fibers, but large-scale applications are followed by clothing applications, interior applications such as curtains and carpets, vehicle interior applications, and industrial materials. It is also expected to be applied to applications.
[0005]
However, polylactic acid fiber has a drawback of poor abrasion resistance due to a high surface friction coefficient, and has not been developed into applications requiring wear resistance such as clothing, interior, and vehicle interior applications. . For example, in applications such as outerwear, uniforms, sportswear, etc., especially in the areas of the shoulders, elbows, knees, buttocks, etc., which are frequently rubbed in daily life, the quality deteriorates due to the occurrence of fluff, whitening, shine, etc. In addition, there is a big problem that color transfer to the innerwear occurs. Furthermore, in applications such as sticking to chairs and carpets, the durability is very poor, such as fluffing and fibres breaking due to repeated friction, and color for clothes such as pants and socks. There were problems such as migration.
[0006]
In order to evaluate the abrasion resistance of such a polylactic acid fiber, the present inventors examined the friction fastness by a gakushin type friction test defined in JIS L0849. In this evaluation method, a dyed textile is rubbed with a cotton cloth, and the color transfer from the textile to the cotton cloth is evaluated. The results showed that polyethylene terephthalate and nylon achieve a rub fastness of 4 or higher as long as a general dye is used, whereas polylactic acid has a very low level of 1st. . Then, when the surface state of the conventional polylactic acid fiber (Comparative Example 1) after rubbing with a cotton cloth was examined by an electron microscope (SEM), polymer scraping occurred due to the friction, and the shaved polymer adhered to the cotton cloth. As a result, it was found that color transfer occurred. In garment applications, it is generally necessary to achieve a rub fastness of at least grade 3 or more, so it has been substantially extremely difficult to develop polylactic acid fibers in such applications.
[0007]
In addition, the high surface friction coefficient of the polylactic acid fiber causes a problem in the fabric processing step. For example, in a fabric cutting process, a plurality of fabrics are cut and overlapped. In this case, in the case of a polylactic acid fabric, large shear heat is generated between the cutter and the fibers, so that the cut ends of the fabric are fused. I will wear it. Furthermore, when sewing a polylactic acid fabric, at a normal sewing speed, the frictional force between the sewing machine needle and the fiber becomes remarkably large, and the heat generated by the friction causes the fiber to be melted, thereby reducing the quality of the product. In addition, the sewing machine needle must be replaced frequently because the polymer adheres to the sewing machine needle, so that the processing can be performed only at a substantially low speed, resulting in a problem that the productivity is significantly reduced.
[0008]
Furthermore, the effect of the high surface friction coefficient of the polylactic acid fiber is not limited to the above-described problems in the abrasion resistance of the fiber product and the problem of the processing step of the fabric, but also the poor process passability in producing the fiber. Degradation has also been reached. For example, in the melt-spinning process, the yarn usually travels at a high speed of 1000 to 7000 m / min, so that the friction between the yarn and the guides increases, so that fluff and yarn breakage are likely to occur. Further, in the stretching step, the yarn is liable to be wound around the roller or the yarn is likely to break. Furthermore, in the crimping step, particularly in the false twisting step, the frictional force between the yarn and the twister becomes excessive, so that the yarn breaks frequently and may be substantially difficult to process. In addition, at the time of weaving and knitting, not only the friction between the yarn and the metal but also the friction between the yarn and the yarn, the generation of fluff is remarkable, and the process passability and the quality of the fabric are greatly reduced. there were. As described above, when producing polylactic acid fiber and its fiber product, the processability is poor and the productivity is reduced, and at the same time, the obtained fiber and fiber product are of low quality due to generation of fluff and abrasion. There was a fatal problem of doing so. .
[0009]
The high coefficient of friction of the polylactic acid fiber, which is the cause of these problems, is due to the polymer matrix and is considered to be an inevitable problem for the polylactic acid fiber.
[0010]
By the way, in the field of resin products, films, sheets, etc., in the manufacturing process, a lubricant is added to the polymer in order to improve the anti-blocking properties of chips and molten polymers, or the peelability of molded products from molds and rollers. May be. However, in the field of fibers, since the blend quality of the lubricant, thermal decomposition, bleed-out, etc. tend to cause deterioration in product quality due to fiber property spots or dye spots, it has not been possible to use such additives until now. There was a tendency to be avoided.
[0011]
As for the fiber to which a lubricant is added, for example, a polylactic acid fiber having the general formula RCONH ₂ There is a method for adding a fatty acid monoamide represented by the following formula (where R is an alkyl group) to suppress the hydrolysis rate by imparting water repellency (see Patent Document 1). There is no description about the improvement of the abrasion resistance and process passability of a certain polylactic acid fiber. As a precautionary measure, the present inventors conducted additional tests on polylactic acid fibers to which a fatty acid monoamide was added, but could not improve the abrasion resistance of polylactic acid fibers and the processability during production (Comparative Example). 2, 3). This is because fatty acid monoamide reacts with polylactic acid at the time of melting due to high reactivity of the amide group, and as a result, the proportion of fatty acid monoamide which can function as a lubricant in the fiber is reduced. Is estimated. Further, when the fatty acid monoamide reacts with the polylactic acid, the molecular chain of the polylactic acid is consequently cut, so that the molecular weight is reduced and the physical properties of the fiber are sometimes reduced. Furthermore, fatty acid monoamides have high sublimability or poor heat resistance, so that the working environment may be deteriorated due to smoking, the guides and rollers may be stained due to bleed-out, and the operability may be reduced. In addition, the bleed-out fatty acid monoamide aggregates on the fiber surface, which may cause unevenness in the physical properties and stain of the fiber.
[0012]
In addition to the fact that the polylactic acid fiber has poor abrasion resistance as described above, there is a disadvantage that the hydrolysis resistance is poor. Due to this, there is a disadvantage that hydrolysis proceeds in hot water treatment such as a dyeing step and the strength is remarkably reduced, and it has been extremely difficult to develop the dyeing application mainly for clothing. As a method of suppressing the strength reduction, there is generally a method of dyeing under low temperature conditions, but in this case, the amount of exhaustion of the dye to the fiber is insufficient, and it is impossible to dye a substantially dark color. Yes, that is, only a dyed product having poor coloring and coloring properties can be obtained. On the other hand, as a technique capable of suppressing a decrease in strength even under high-temperature dyeing conditions, for example, there is a technique of blocking a terminal carboxyl group of polylactic acid with a so-called terminal blocking agent such as a carbodiimide compound (see Patent Document 2). Certainly, the hydrolysis resistance of polylactic acid is improved, but the resulting polylactic acid fiber is colored yellow due to thermal deterioration of the terminal blocking agent during molding. In particular, when a polycarbodiimide compound is used as a terminal blocking agent, this phenomenon appears remarkably. In other words, when the terminal of polylactic acid is blocked by a polycarbodiimide compound, a crosslinked structure is introduced with the blockade, so that the melt viscosity inevitably increases, and the moldability decreases remarkably. Therefore, in order to lower the melt viscosity, the polymer is generally melted under a high temperature condition. At this time, as described above, the polymer is further colored yellow due to thermal deterioration of the polycarbodiimide compound, and as a result, a high-quality fiber is obtained. It becomes difficult. For this reason, when dyeing a polylactic acid fiber end-blocked with a carbodiimide compound, color matching is difficult due to the yellowish taste, and it is virtually impossible to express a particularly vivid color. In fact, there have been significant restrictions on the development of dyeing applications, mainly for clothing.
[0013]
[Patent Document 1]
JP-A-8-183898 (pages 2-4)
[0014]
[Patent Document 2]
JP-A-2002-180328 (pages 2-6)
[0015]
[Problems to be solved by the invention]
The present invention provides a polylactic acid fiber which overcomes the above-mentioned problems, has excellent abrasion resistance and hydrolysis resistance, has less yellow coloring of the fiber itself, and further has excellent coloring property at the time of dyeing. Make it an issue.
[0016]
[Means for Solving the Problems]
The above object is achieved by a polylactic acid fiber containing a fatty acid bisamide and / or an alkyl-substituted fatty acid monoamide, and having a carbodiimide compound in which a carboxyl group terminal is blocked.
[0017]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described in detail.
[0018]
The polylactic acid referred to in the present invention refers to a product obtained by polymerizing an oligomer of lactic acid such as lactic acid or lactide. It is preferable that the optical purity of the L-form or D-form is 90% or more because the melting point is high. The optical purity of the L-form or D-form is more preferably 97% or more. A blend of polylactic acid having an optical purity of L-form of 90% or more and polylactic acid having an optical purity of D-form of 90% or more in a ratio of 70/30 to 30/70 is preferable because the melting point is further improved. Also, to the extent that the properties of polylactic acid are not impaired, even if components other than lactic acid are copolymerized, polymers and particles other than polylactic acid, flame retardants, antistatic agents, matting agents, deodorants, antibacterial agents, It may contain additives such as antioxidants and coloring pigments. When the molecular weight of the polylactic acid polymer is 50,000 to 500,000 in terms of weight average molecular weight, a good balance between mechanical properties and moldability is preferable.
[0019]
The fatty acid bisamide referred to in the present invention refers to a compound having two amide bonds in one molecule such as a saturated fatty acid bisamide, an unsaturated fatty acid bisamide, an aromatic fatty acid bisamide and the like, for example, methylene biscaprylic amide, methylene biscapric acid Amide, methylenebislauric amide, methylenebismyristic amide, methylenebispalmitic amide, methylenebisstearic amide, methylenebisisostearic amide, methylenebisbehenic amide, methylenebisoleic amide, methylenebiserucic acid Amide, ethylene biscaprylic amide, ethylene biscapric amide, ethylene bislauric amide, ethylene bismyristic amide, ethylene bispalmitic amide, ethylene bis stearic amide, ethylene biamide Isostearic acid amide, ethylene bisbehenic acid amide, ethylene bis oleic acid amide, ethylene bis erucic acid amide, butylene bis stearic acid amide, butylene bis behenic acid amide, butylene bis oleic acid amide, butylene bis erucic acid amide, Hexamethylenebisstearic acid amide, hexamethylenebisbehenic acid amide, hexamethylenebisoleic acid amide, hexamethylenebiserucic acid amide, m-xylylenebisstearic acid amide, m-xylylenebis-12-hydroxystearic acid amide, p-xylylenebisstearic acid amide, p-phenylenebisstearic acid amide, p-phenylenebisstearic acid amide, N, N′-distearyladipamide, N, N′-distearylsebacic acid amide, N'-dioleyl adipic amide, N, N'-dioleyl sebacic amide, N, N'-distearyl isophthalic amide, N, N'-distearyl terephthalic amide, methylene bishydroxystearic amide, ethylene Bishydroxystearic acid amide, butylene bishydroxystearic acid amide, hexamethylenebishydroxystearic acid amide and the like can be mentioned. The alkyl-substituted fatty acid monoamide referred to in the present invention refers to a compound having a structure in which an amide hydrogen such as a saturated fatty acid monoamide or an unsaturated fatty acid monoamide is replaced with an alkyl group, and examples thereof include N-lauryl lauric amide and N-lauryl lauric amide. Palmityl palmitic amide, N-stearylstearic amide, N-behenylbehenic amide, N-oleyloleic amide, N-stearyloleic amide, N-oleylstearic amide, N-stearylerucic acid amide, N-oleyl Palmitic acid amide and the like. The alkyl group may have a substituent such as a hydroxyl group introduced into its structure. Examples of the alkyl group include methylol stearamide, methylol behenic acid amide, N-stearyl-12-hydroxystearic acid amide, N- Oleyl 12-hydroxystearic acid amide and the like are also included in the alkyl-substituted fatty acid monoamide of the present invention.
[0020]
In the present invention, fatty acid bisamides or alkyl-substituted fatty acid monoamides are used. However, these compounds have lower amide reactivity than ordinary fatty acid monoamides, and do not easily react with polylactic acid during melt molding. In addition, since many of them have high molecular weight, they generally have good heat resistance and are hardly sublimated. In particular, fatty acid bisamides can be used as more preferable lubricants because they are less reactive with polylactic acid due to lower reactivity of amides, and because they have a high molecular weight, they have good heat resistance and do not easily sublime. Examples of such a lubricant include ethylene bisstearic acid amide, ethylene bisisostearic acid amide, ethylene bisbehenic acid amide, butylene bisstearic acid amide, butylene bisbehenic acid amide, hexamethylene bisstearic acid amide, Hexamethylene bisbehenic acid amide and m-xylylene bis stearic acid amide are preferably used.
[0021]
The content of the fatty acid bisamide and / or the alkyl-substituted fatty acid monoamide (hereinafter, abbreviated as fatty acid amide) in the present invention with respect to the whole fiber is not particularly limited, but is preferably 0.1 to 5% by weight. By adjusting the content of the fatty acid amide to 0.1 wt% or more, the surface friction coefficient of the fiber is reduced, and the fiber product is provided with abrasion resistance required for clothing use and durability in repeated use. Can be. Further, the fusion and melting of the fabric by a cutting cutter or a high-speed sewing needle in the fabric processing step can be suppressed, and the process passability can be improved. Further, when the content of the fatty acid amide is 5 wt% or less, the fatty acid amide can be finely dispersed, and the occurrence of unevenness in physical properties and staining of the fiber can be prevented. The content of the fatty acid amide is more preferably 0.5 to 3 wt%. The fatty acid amide may be a single component or a mixture of a plurality of components.
[0022]
The polylactic acid fiber of the present invention is preferably provided with a spinning oil agent containing a leveling agent. The leveling agent is not particularly limited, but examples thereof include fatty acid esters, polyhydric alcohol esters, ether esters, polyethers, silicones, and mineral oils. Further, these smoothing agents may be used as a single component, or a mixture of a plurality of components may be used. By applying an oil agent containing the above-mentioned smoothing agent to the polylactic acid fiber, it is possible to further suppress the occurrence of yarn breakage and fluff in the spinning and drawing steps, and winding around a roller. In addition, the false twisting process, in which the conventional polylactic acid fiber has poor process passage properties, can be performed with good process passability by reducing the frictional force between the yarn and the twister and suppressing yarn breakage. Furthermore, in the weaving process, the friction between the yarn and the metal or between the yarns is reduced, and a high-quality fiber product can be obtained by suppressing generation of fluff.
[0023]
In the present invention, the components constituting the oil agent, in addition to the smoothing agent, emulsify the oil agent in water, reduce the viscosity to adhere to the yarn, improve the permeability, an antistatic agent, if necessary, It is possible to use those appropriately blended with a surfactant, a sizing agent, a rust inhibitor, a preservative, and an antioxidant.
[0024]
The carbodiimide compound referred to in the present invention is not particularly limited. For example, monocarbodiimide compounds include N, N'-di-2,6-diisopropylphenylcarbodiimide, N, N'-di-2,6 -Di-tert. -Butylphenylcarbodiimide, N, N'-di-2,6-diethylphenylcarbodiimide, N, N'-di-2-ethyl-6-isopropylphenylcarbodiimide, N, N'-di-2-isobutyl-6 Isopropylphenylcarbodiimide, N, N'-di-2,4,6-trimethylphenylcarbodiimide, N, N'-di-2,4,6-triisopropylphenylcarbodiimide, N, N'-di-2,4, 6-triisobutylphenylcarbodiimide and the like. As the polycarbodiimide compound, a polymer obtained by polymerizing a diisocyanate compound as described in JP-A-11-80522 is preferably used. Among them, a polymer of 4,4′-dicyclohexylmethanecarbodiimide and a tetramethylxylylenecarbodiimide are preferable. And those whose terminals are blocked with polyethylene glycol or the like are preferably used. These carbodiimide compounds may be used alone or in combination of two or more.
[0025]
The content of the carbodiimide compound in the present invention is not particularly limited. However, if the carbodiimide compound is contained such that the carboxyl group terminal concentration of the polylactic acid polymer is 10 equivalents / ton or less based on the entire polylactic acid fiber, the polylactic acid fiber can be used. Is preferable because the hydrolysis resistance can be dramatically improved.
[0026]
The polylactic acid fiber of the present invention is used as an index of yellowish color, because it is widely used in applications where color is important such as clothing, interiors, and vehicle interiors where dyeing is premised. ^* The value is preferably from -1 to 6, and more preferably from -1 to 4. In addition, the polylactic acid fiber containing the fatty acid monoamide, which is a conventional technique, is b ^* The value may be high and the yellow color tends to be strong. This is presumably because, in addition to the thermal degradation of the fatty acid monoamide having poor heat resistance, the fatty acid monoamide reacts with the carbonyl group of the polylactic acid polymer during melt molding to form a diacetamide group. On the other hand, the fatty acid bisamide and the alkyl-substituted fatty acid monoamide of the present invention have excellent heat resistance and low reactivity of the amide group, so that the coloring of the fiber hardly occurs.
[0027]
In addition, polylactic acid fibers containing a carbodiimide compound, which is a conventional technique, are also b ^* The value may be high and the yellow color tends to be strong. It is presumed that this is due to thermal deterioration of the carbodiimide compound during melting.According to the present invention, it is possible to suppress thermal deterioration of the carbodiimide compound and to suppress yellowing of the polymer accompanying the deterioration. .
[0028]
This principle can be explained as follows. That is, the polylactic acid containing the carbodiimide compound is once melted into fibers, and in order to suppress the thermal deterioration of the carbodiimide compound at this time, it is desired to lower the spinning temperature as much as possible. However, polylactic acid containing a carbodiimide compound generally has a high melt viscosity, and a high spinning temperature must be set for stable spinning, which inevitably promotes thermal deterioration of the carbodiimide compound. is there. In particular, in the case of a polycarbodiimide compound, a crosslinked structure is introduced with the terminal block of polylactic acid, so that the melt viscosity is significantly increased, and high-temperature spinning conditions are essential. However, the present invention is characterized in that the fatty acid bisamide and the alkyl-substituted fatty acid monoamide are contained in the polylactic acid fiber, whereby the spinning temperature can be set low. In other words, the inventors have noticed that fatty acid bisamides and alkyl-substituted fatty acid monoamides not only function as a lubricant but also as a plasticizer, and by including this in polylactic acid, the melt viscosity is significantly reduced. It was found that it was possible to do so. As a result, even in the case of a polylactic acid fiber containing a carbodiimide compound, stable spinning can be performed at a low temperature without causing an increase in viscosity, and simultaneously with suppression of thermal deterioration of the carbodiimide compound, yellow coloring of the obtained polylactic acid fiber can be achieved. Can be suppressed.
[0029]
In the polylactic acid fiber of the present invention, the strength is preferably 2.0 cN / dtex or more in order to keep the process passability and the mechanical strength of the product sufficiently high. When the elongation of the polylactic acid fiber of the present invention is from 15 to 70%, the processability in producing a fiber product is preferably improved. In the polylactic acid fiber of the present invention, if the boiling point is 0 to 20%, the dimensional stability of the fiber and the fiber product is good, which is preferable. If the U% (normal) representing the unevenness in the thickness of the yarn is 1.5% or less, it is preferable because unevenness in dyeing hardly occurs and a high-quality dyed fiber product can be obtained. U% (normal) is more preferably 1.0% or less.
[0030]
The fineness of the polylactic acid fiber of the present invention is not particularly limited, but when used for clothing, the total fineness of the multifilament is 500 dtex or less, and the single yarn fineness is preferably 0.1 to 10 dtex. . In general, poor wear resistance of polylactic acid fiber appears more remarkably as the single yarn fineness is smaller. However, the polylactic acid fiber of the present invention has sufficient wear resistance even if the single yarn fineness is small.
[0031]
In addition, the cross-sectional shape of the polylactic acid fiber of the present invention can be freely selected from a multi-lobal cross-section such as a round cross-section, a hollow cross-section, a three-lobed cross-section, and other irregular cross sections. The form of the fibers is not particularly limited, such as long fibers and short fibers. In the case of long fibers, multifilaments or monofilaments may be used. Further, the polylactic acid fiber of the present invention is a composite fiber of a type that elutes one component such as a core-sheath type, an eccentric core-sheath type, a side-by-side type, a split fiber split type, or a sea-island type containing at least polylactic acid as a component. It may be. Furthermore, the polylactic acid fiber of the present invention may be an ordinary flat yarn, a thick and thin yarn, a twisted yarn, or a bulky crimped yarn by a false twisting method, a stuffing method, a high-pressure air jet method, or the like.
[0032]
The polylactic acid fiber structure in the present invention is not particularly limited as long as polylactic acid fibers are used for at least a part thereof, and can take various forms such as a woven fabric, a knitted fabric, and a nonwoven fabric. Also, fibers other than polylactic acid fibers, for example, biodegradable fibers such as polyglycolic acid, polyhydroxybutyrate, polybutylene succinate, polycaprolactone, natural fibers such as cotton, silk, hemp, wool, rayon and acetate Recycled fiber such as polyethylene terephthalate, nylon, acrylic, vinylon, polyolefin, polyurethane and the like.
[0033]
In the present invention, the polylactic acid fiber structure is dyed at least with a disperse dye, and the lightness index L ^* C is less than or equal to 15 and is an index of saturation ^* When the value is 8 or less, it is preferable because dark color characteristics required for dyeing applications such as clothing can be satisfied. L ^* Value is 10 or less and C ^* When the value is 5 or less, a color such as black or navy becomes a deeper color, and the range of application to formal wear or the like is expanded, which is more preferable.
[0034]
Further, in the present invention, the polylactic acid fiber structure is dyed at least with a disperse dye, and C is an index of chroma. ^* A value of 25 or more is preferable because it can satisfy the characteristics of clear color required for dyeing applications such as clothing. When the C * value is 35 or more, red, blue, yellow, or an intermediate color thereof becomes more vivid, and the range of application to outerwear, curtains, carpets, and the like is widened.
[0035]
The so-called dyeing and coloring properties such as the deep color and the vivid color described above indicate that the polylactic acid fiber of the present invention contains a fatty acid bisamide and / or an alkyl-substituted fatty acid monoamide, and the carboxyl group terminal is blocked with a carbodiimide compound. Is achieved for the first time. According to the present invention, the following two factors can be considered as factors that improve the coloring and coloring properties.
[0036]
First, the polylactic acid fiber of the present invention contains a fatty acid bisamide and / or an alkyl-substituted fatty acid monoamide. When the fatty acid amide is contained in the polylactic acid fiber, the dye has an increased amount of exhaustion, and a part of the fatty acid amide bleeds out to the surface of the polylactic acid fiber to reduce the refractive index of the fiber surface. As a result, the dye coloring property is greatly improved as compared with the polylactic acid fiber containing no fatty acid amide.
[0037]
Secondly, the polylactic acid fiber of the present invention has a carbodiimide compound in which the terminal of the carboxyl group is blocked. A polylactic acid fiber having a carboxyl group terminal blocked with a carbodiimide compound has improved hydrolysis resistance, and a fiber which retains practical strength even when dyed under high temperature conditions can be obtained. Therefore, the amount of dye exhaustion can be increased by high-temperature dyeing. The polylactic acid fiber structure of the present invention can achieve excellent coloring and coloring properties, which were insufficient with the conventional polylactic acid fiber structure, due to the synergistic effect of these two factors.
[0038]
As described above, according to the present invention, it is possible to provide a polylactic acid fiber which is excellent in abrasion resistance and hydrolysis resistance, has little yellow coloring of the fiber itself, and is excellent in coloring property at the time of dyeing.
[0039]
The polylactic acid fiber of the present invention can be used for all applications requiring abrasion resistance and dyeing and coloring, for example, clothing applications such as suits, jackets, pants, skirts, shirts, inners, linings, curtains, carpets, mats, and wallpapers. It can be suitably used for interior applications such as chairs and furniture, and for vehicle members such as car mats and car seats.
[0040]
【Example】
Hereinafter, the present invention will be described in detail with reference to examples. In addition, the following method was used for the measuring method in an Example.
A. Weight average molecular weight
The measurement was carried out using gel permeation chromatography "Shimadzu LC-10AD" manufactured by Shimadzu Corporation with polystyrene as a standard.
B. Fiber color tone (b * value)
The fiber sample was densely layered and wound on a transparent plate to such an extent that the underlying color was almost negligible, and the measurement was carried out using "Spectrophotometer CM-3700d" manufactured by Minolta. At this time, the measurement was performed in a 10 ° visual field using D65 (color temperature 6504K) as a light source.
C. Strength and elongation
Using "Tensilon UTM-100III" manufactured by Orientec, a load-elongation curve was determined at room temperature (25 ° C) with an initial sample length of 200 mm and a tensile speed of 200 mm / min. Next, the load value at break was divided by the initial fineness, which was taken as strength, the elongation at break was divided by the initial sample length, and the elongation curve was determined as elongation. (Based on JIS L 1013)
D. Boiling
It was determined from the following equation.
[0041]
Boiling yield (%) = [(L0−L1) / L0)] × 100 (%)
L0: The original length of the skein of the drawn yarn measured under an initial load of 0.088 cN / dtex
L1: The skein for which L0 was measured was treated in boiling water for 15 minutes in a substantially load-free state, and after air-drying, the skein length under an initial load of 0.088 cN / dtex
E. FIG. U%
Using a “Wooster Tester 1 MODEL C” manufactured by Zuerbeger Co., Ltd., the thickness unevenness of the yarn was measured in a normal mode at 200 m / min × 1 minute.
F. Carboxyl group terminal concentration
As described in JP-A-2001-261797, a weighed sample is dissolved in o-cresol adjusted to a water content of 5%, an appropriate amount of dichloromethane is added, and the sample is titrated with a 0.02 N KOH methanol solution to obtain a sample. Was.
G. FIG. Η after hydrothermal treatment _r Retention rate (Rη _r )
After the fiber sample was formed into a tubular knit, it was calculated by the following method.
[0042]
Solution specific viscosity before hot water treatment η _r1 : A solution in which 3 g of a weighed sample was dissolved in 100 ml of o-chlorophenol was prepared, and the solution was measured at 25 ° C using an Ostwald viscometer.
[0043]
Solution specific viscosity η after hot water treatment _r2 : 30 g of a sample and 300 g of water were placed in a pressure vessel and subjected to a hot water treatment at 120 ° C. for 60 minutes. Then, this specific viscosity is expressed as η _r1 It was measured in the same manner as described above.
[0044]
Η obtained _r1 And η _r2 From the following equation: _r I asked.
[0045]
Rη _r (%) = (Η _r2 / Η _r1 ) × 100 (%)
H. Strength retention after hot water treatment (RT)
After the fiber sample was formed into a tubular knit, it was calculated by the following method.
[0046]
Strength T before hot water treatment ₁ : The yarn was released from the tubular knitting, and measured by the method shown in C.
[0047]
Strength T after hot water treatment ₂ : 30 g of a sample and 300 g of water were placed in a pressure vessel and subjected to a hot water treatment at 120 ° C. for 60 minutes. And this intensity | strength was measured by the method similar to T1.
[0048]
The obtained T ₁ And T ₂ RT was obtained from the following equation.
[0049]
RT (%) = (T ₂ / T ₁ ) × 100 (%)
I. Color tone of dyed fabric (L ^* Value, C ^* value)
The four-fold folded dyed fabric sample was measured using Minolta's “Spectrophotometer CM-3700d”. At this time, the light source is D ₆₅ (Color temperature: 6504K), the measurement was performed in a 10 ° visual field.
J. Spots
The dyed fabric samples were evaluated visually. △ or more passes.
[0050]
○: no staining spots
Δ: Slight unevenness, but no problem
×: Many staining spots
K. Tear strength
A test piece of 10 cm long × 6.5 cm wide was set using “Elmendorf Tear Strength Meter” manufactured by Daiei Kagaku Seiki KK, and a cutter handle of the test machine was pulled to make a 2 cm cut. The fan-shaped pendulum was dropped by pressing the drop button, the remaining 4.5 cm of the test piece was torn, and the strength at this time was read. In the test, the vertical direction and the horizontal direction were repeated three times each, and the average value was taken as the tear strength of the fabric.
L. Abrasion resistance (dry friction fastness)
After the dyed fabric sample was rubbed back and forth 100 times with a cotton cloth, the degree of color transfer to the cotton cloth was determined using a gray scale using a first to fifth grade. (Based on JIS L0849)
M. SEM observation
Using "HITACHI S-3000N" manufactured by Hitachi, Ltd., the surface of the fabric after the friction test was observed.
N. TG (thermogravimetry)
Using “TG-DTA 2000S” manufactured by Mac Science, the weight loss rate of the sample was measured when about 10 mg of the sample was heated from 30 ° C. at a rate of 10 ° C./min.
[Production Example 1] (Production of polylactic acid P1)
Lactide produced from L-lactic acid having an optical purity of 99.5% was polymerized in the presence of a bis (2-ethylhexanoate) tin catalyst (lactide to catalyst molar ratio = 10000: 1) at 180 ° C. for 140 minutes in a nitrogen atmosphere. This was performed to obtain polylactic acid P1. The obtained polylactic acid had a weight average molecular weight of 135,000 and a carboxyl group terminal concentration of 35 equivalents / ton.
[Production Example 2] (Production of polylactic acid P2 containing 4 wt% of EBA)
After drying P1 and ethylenebisstearic acid amide (EBA) of fatty acid bisamide (“Alflow H-50S” manufactured by NOF Corporation), EBA heated and melted so that P1: EBA = 96: 4 (weight ratio) is obtained. While being weighed and continuously added to P1, the mixture was supplied to a twin-screw kneading extruder at a cylinder temperature of 220 ° C. to obtain polylactic acid P2 containing 4% by weight of EBA. The carboxyl group terminal concentration was 36 equivalents / ton.
[Production Example 3] (Production of polylactic acid P3 containing 4 wt% SS)
Polylactic acid P3 containing 4 wt% SS was obtained in the same manner as in Production Example 2 except that the EBA was changed to an alkyl-substituted monoamide N-stearylstearic acid amide (SS) ["Nikka Amide S" manufactured by Nippon Kasei Co., Ltd.] Was. The carboxyl group terminal concentration was 36 equivalents / ton.
[Production Example 4] (Production of polylactic acid P4 containing 4 wt% of SA)
Polylactic acid P4 containing 4 wt% of SA was obtained in the same manner as in Production Example 2 except that EBA was changed to monoamide stearic acid amide (SA) [“Alflow S-10” manufactured by NOF Corporation]. The carboxyl group terminal concentration was 37 equivalents / ton.
[Production Example 5] (Production of polylactic acid P5 containing 10 wt% of PCI)
After drying P1 and the polycarbodiimide compound (PCI) [thermoplastic polycarbodiimide “Carbodilite HMV-8CA” manufactured by Nisshinbo Co., Ltd. (1 equivalent of carbodiimide group / 278 g)], P1: PCI = 90: 10 (weight ratio). The heated and melted PCI was weighed and continuously added to P1 and supplied to a twin-screw kneading extruder at a cylinder temperature of 220 ° C. to obtain a polylactic acid P5 containing 10 wt% of PCI. The carboxyl group terminal concentration was below the detection limit of 5 equivalents / ton.
[Production Example 6] (Production of polylactic acid P6 containing 10 wt% of TIC)
Except that PCI was changed to N, N'-di-2,6-diisopropylphenylcarbodiimide (TIC) of a monocarbodiimide compound ["Stabacol I" manufactured by Bayer AG (1 equivalent of carbodiimide group / 362 g)], the same as in Production Example 5 Thus, polylactic acid P6 containing 10 wt% of TIC was obtained. The carboxyl group terminal concentration was below the detection limit of 5 equivalents / ton.
[0051]
[Fabric processing method]
・ Scouring: soda ash (1 g / l), surfactant (0.5 g / l), 98 ° C. × 20 minutes ・ Intermediate set: 140 ° C. × 3 minutes
Dyeing: Any one of the following dyeing methods 1 to 3 was used.
・ Soaping: surfactant (0.2 g / l), 60 ° C. × 20 minutes
・ Finishing set: 140 ° C. × 3 minutes.
[0052]
[Dyeing method 1]
Dyeing temperature 120 ° C or 110 ° C
Staining time 40 minutes
Dye Dianix Black BG-FS (manufactured by Dystar)
Dye concentration 8% owf
Bath ratio 1:50
Bath pH 4.5.
[0053]
[Dyeing method 2]
Dyeing temperature 120 ° C or 110 ° C
Staining time 40 minutes
Dye Kayalon Polyester Ruby BL-S 200 (manufactured by Nippon Kayaku Co., Ltd.)
Dye concentration 2% owf
Bath ratio 1:50
Bath pH 4.5.
[0054]
[Dyeing method 3]
Dyeing temperature 120 ° C or 110 ° C
Staining time 40 minutes
Dye Miketon Polyester Blue RSE (Mitsui BASF Dye Company)
Dye concentration 5% owf
Bath ratio 1:50
Bath pH 4.5.
[0055]
Example 1
Chip blending (EBA: 1 wt%, carbodiimide group content of PCI: 1.2 times equivalent to carboxyl group terminal content of polylactic acid) so that P1: P2: P5 = 63: 25: 12 in weight ratio, and hopper After the chips were melted at 220 ° C. in an extruder 2, the molten polymer was guided to a spinning pack 4 installed in a spin block 3 heated to 220 ° C. and discharged from a die 5 (FIG. 3). The spun yarn 7 is cooled and solidified by a chimney 6 with a cooling air at 25 ° C., and then a fatty acid ester-based smoothing agent is 40 wt% (isotridecyl stearate 20 wt% + octyl palmitate 20 wt%) by a bundled lubrication guide 8. ) Was applied to the fiber at 1 wt%, and the yarn was entangled by the entanglement guide 9. Thereafter, the film was taken up by a non-heated first take-up roller 10 having a peripheral speed of 3000 m / min, and then wound up through a non-heated second take-up roller 11 to obtain a wound yarn 12. The pack pressure was stable throughout, and there was almost no smoke right under the base. No yarn breakage or fluff was observed, and the spinnability was extremely good.
[0056]
The obtained undrawn yarn 13 is preheated by a first hot roller 15 at 90 ° C. via a feed roller 14, then drawn 1.45 times, heat set by a second hot roller 16 at 130 ° C., and cold It was wound up via a roller 17 to obtain a drawn yarn 18 having a round section of 84 dtex, 36 filaments (FIG. 4). The extensibility was good without a single turn or the like, and no fuzz was attached to the guides.
[0057]
The resulting fiber is b ^* The value was 3.1 and the color tone was good with little yellowness. In addition, the carboxyl group terminal concentration is 5 equivalents / ton or less, which is the detection limit, and η after hot water treatment _r The retention and strength retention were good and showed excellent hydrolysis resistance.
[0058]
Using this fiber as a warp and a weft, a plain woven fabric (woven density: warp 95 / inch, weft 80 / inch) was produced. The warp was S-twisted at 300 turns / m. At this time, almost no yarn breakage or fluff was generated in the twisting step and the weaving step, and excellent passability of the weaving step was exhibited. Further, this fabric was subjected to a dyeing process using a dyeing method 1 (a dyeing temperature of 120 ° C.). The resulting fabric had an excellent texture with little mechanical creaking feeling unique to polylactic acid fibers, while being flexible and soft. Also, L ^* Value 8.8, C ^* The value of 1.2 showed good black coloring. The tear strength of the fabric was also excellent at 920 cN.
[0059]
Further, when the rub fastness of the varnish was measured, it was grade 4 and excellent in abrasion resistance. In addition, as a result of observing the surface of the fabric after the friction test with SEM, almost no abrasion of the yarn occurred (FIG. 1).
[0060]
Further, using this dyed fabric, industrial cutting and industrial sewing were performed, but there was no fusion at the cutting portion of the fabric at the time of cutting, and the stain on the sewing needle was very small, showing excellent process passability. . Further, a durability test was carried out by using this to make a shirt and wear it for one month. As a result, there was no fluff, no whitening and no shine, and excellent product durability was shown.
[0061]
Example 2
A dyed fabric was obtained in the same manner as in Example 1, except that Dyeing Method 2 (dyeing temperature: 120 ° C) was used. The resulting fabric is L ^* Value 34.2, C ^* A value of 52.1 showed good red vivid color development. The tear strength of the fabric was also excellent at 920 cN.
[0062]
Further, when the rub fastness of the varnish was measured, it was grade 4 and excellent in abrasion resistance. Further, using this dyed fabric, industrial cutting and industrial sewing were performed, but there was no fusion at the cutting portion of the fabric at the time of cutting, and the stain on the sewing needle was very small, showing excellent process passability. . Further, a durability test was carried out by using this to make a shirt and wear it for one month. As a result, there was no fluff, no whitening and no shine, and excellent product durability was shown.
[0063]
Example 3
Chip blending (3.5 wt% of EBA, the carbodiimide group content of PCI is 1.2 times equivalent to the carboxyl group terminal content of polylactic acid) so that P2: P5 = 88: 12 by weight ratio, and the spinning temperature Was set to 210 ° C., and an extruded trilobe cross-section yarn of 84 dtex and 36 filaments was obtained in the same manner as in Example 1 except that the die discharge hole was changed to the Y hole. Despite the relatively low spinning temperature of 210 ° C., the pack pressure was stable throughout without any increase in pressure, and there was little smoke immediately below the spinneret. Since the amount of EBA added was larger than that in Example 1, the viscosity of the polymer was lowered, and as a result, stable spinning was possible even when the spinning temperature was set low. No yarn breakage or fluff was observed, and the spinnability was extremely good. Also, the stretchability was good without a single turn or the like, and no fuzz was attached to the guides.
[0064]
The resulting fiber is b ^* The value was 2.6, which was a good color tone with little yellowness. In addition, the carboxyl group terminal concentration is 5 equivalents / ton or less, which is the detection limit, and η after hot water treatment _r The retention and strength retention were good and showed excellent hydrolysis resistance.
[0065]
Further, the obtained dyed fabric is L ^* Value 8.5, C ^* A value of 1.3 showed good black coloring. The tear strength of the fabric was also excellent at 940 cN.
[0066]
Further, when the rub fastness of the varnish was measured, it was grade 5 and was very excellent in abrasion resistance.
[0067]
Example 4
A dyed fabric was obtained in the same manner as in Example 3, except that the dyeing temperature was changed to 110 ° C. The resulting fabric is L ^* Value 13.5, C ^* A value of 1.5 showed good black coloring. The tear strength of the fabric was 960 cN, showing excellent fabric properties.
[0068]
Further, when the rub fastness of the varnish was measured, it was grade 5 and was very excellent in abrasion resistance.
[0069]
Example 5
Chip blending (EBA: 0.3 wt%, carbodiimide group content of PCI is 1: 1 with respect to carboxyl group terminal content of polylactic acid) so that P1: P2: P5 = 80.5: 7.5: 12 by weight ratio. (Equivalent to 2 times), and a drawn yarn of 84 dtex and 36 filaments was obtained in the same manner as in Example 1 except that the spinning temperature was 225 ° C. The pack pressure was stable throughout, and there was little smoke immediately below the base. No yarn breakage or fluff was observed, and the spinnability was extremely good. Also, the stretchability was good without a single turn or the like, and no fuzz was attached to the guides.
[0070]
The resulting fiber is b ^* The value was 3.5, which was a good color tone with little yellowness. In addition, the carboxyl group terminal concentration is 5 equivalents / ton or less, which is the detection limit, and η after hot water treatment _r The retention and strength retention were good and showed excellent hydrolysis resistance.
[0071]
Further, the obtained dyed fabric is L ^* Value 9.2, C ^* A value of 1.3 showed good black coloring. The tear strength of the fabric was also excellent at 920 cN.
[0072]
Further, when the rub fastness of the varnish was measured, the varnish was grade 3 and excellent in abrasion resistance.
[0073]
Example 6
Chip blending (EBA: 0.1 wt%, PCI carbodiimide group content is 1: 1 based on carboxyl group terminal content of polylactic acid) so that P1: P2: P5 = 85.5: 2.5: 12 by weight ratio. (2 equivalents), the spinning temperature was set to 235 ° C., and a drawn yarn of 84 dtex and 36 filaments was obtained in the same manner as in Example 1 except that Dyeing Method 3 (dyeing temperature of 120 ° C.) was used. Although the pack pressure was stable from beginning to end, some smoke was generated immediately below the mouthpiece due to thermal decomposition of polylactic acid and PCI. Also, there was almost no occurrence of yarn breakage or fluff, and the spinnability was good. In addition, the film had good stretchability, almost no single winding, etc., and showed little fuzz on the guides.
[0074]
The resulting fiber is b ^* Although the value was 6.5, which was not excellent, the color tone was reasonably good. In addition, the carboxyl group terminal concentration is 5 equivalents / ton or less, which is the detection limit, and η after hot water treatment _r The retention and strength retention were good and showed excellent hydrolysis resistance.
[0075]
Further, the obtained dyed fabric is L ^* Value 30.7, C ^* Although a good vivid color development was obtained at a value of 37.8, the hue was slightly yellowish due to the yellow tinting of the fiber itself. The tear strength of the fabric was 840 cN, indicating a reasonably excellent fabric characteristic.
[0076]
Example 7
Chip blending (EBA: 0.05 wt%, PCI: carbodiimide group content: 1: 1 based on carboxyl group terminal content of polylactic acid) so that P1: P2: P5 = 86.75: 1.25: 12 by weight ratio. (2 equivalents), the spinning temperature was set to 240 ° C., and a drawn yarn of 84 dtex and 36 filaments was obtained in the same manner as in Example 1 except that Dyeing Method 3 (dyeing temperature of 120 ° C.) was used. Although the pack pressure was stable from beginning to end, some smoke was generated immediately below the mouthpiece due to thermal decomposition of polylactic acid and PCI. Also, there was almost no occurrence of yarn breakage or fluff, and the spinnability was good. In addition, the film had good stretchability, almost no single winding, etc., and showed little fuzz on the guides.
[0077]
The resulting fiber is b ^* Although the value was 7.7, which was not excellent, the color tone was fairly good. In addition, the carboxyl group terminal concentration is 5 equivalents / ton or less, which is the detection limit, and η after hot water treatment _r The retention and strength retention were good and showed excellent hydrolysis resistance.
[0078]
Further, the obtained dyed fabric is L ^* Value 30.5, C ^* Although the value was 34.8, which was a good clear color developing property, the color was slightly yellowish due to the yellowish coloring of the fiber itself. The tear strength of the fabric was also reasonably excellent at 800 cN.
[0079]
Example 8
The number of die holes was set to 24, the peripheral speed of the take-off roller was 5000 m / min, the temperature of the first hot roller was 140 ° C, the stretching ratio was 1.65 times, and the temperature of the second hot roller was changed to 150 ° C. In addition, a drawn yarn of 84 dtex and 24 filaments was obtained in the same manner as in Example 1 except that the dyeing method 3 (dyeing temperature: 120 ° C.) was used. The spinnability was good, and no yarn breakage or fluff was observed. In addition, the stretchability was good without a single turn or the like, and no fuzz was attached to the guides.
[0080]
The resulting fiber is b ^* The value was 2.9, indicating a good yellow tone with little yellowness. In addition, the carboxyl group terminal concentration is 5 equivalents / ton or less, which is the detection limit, and η after hot water treatment _r The retention and strength retention were good and showed excellent hydrolysis resistance.
[0081]
Further, the obtained dyed fabric is L ^* Value 30.1, C ^* The value was 45.2, indicating good clear color development of blue. The tear strength of the fabric was 950 cN, showing excellent fabric properties.
[0082]
Further, when the rub fastness of this product was measured, it was grade 4 and was very excellent in abrasion resistance.
[0083]
Further, using this dyed fabric, industrial cutting and industrial sewing were performed, but there was no fusion at the cutting portion of the fabric at the time of cutting, and the stain on the sewing needle was very small, showing excellent process passability. . Further, a shirt was produced using the same, and a durability test was conducted in which the shirt was worn for one month. As a result, there was no fluff, no whitening and no shine, and excellent product durability was exhibited.
[0084]
Example 9
Example 1 Example 2 was repeated except that the number of die holes was changed to 24, the peripheral speed of the take-off roller was changed to 1500 m / min, the stretching ratio was changed to 2.4 times, and the dyeing method 3 (dying temperature 110 ° C.) was used. In the same manner as described above, a drawn yarn of 84 dtex and 24 filaments was obtained. The spinnability was good, and no yarn breakage or fluff was observed. In addition, the stretchability was good without a single turn or the like, and no fuzz was attached to the guides.
[0085]
The resulting fiber is b ^* The value was 3.3, which was a good color tone with little yellowness. In addition, the carboxyl group terminal concentration is 5 equivalents / ton or less, which is the detection limit, and η after hot water treatment _r The retention and strength retention were good and showed excellent hydrolysis resistance.
[0086]
Further, the obtained dyed fabric is L ^* Value 37.3, C ^* With a value of 40.1, good blue vivid color development was exhibited. The tear strength of the fabric was also excellent at 930 cN.
[0087]
Further, when the rub fastness of the varnish was measured, it was grade 4 and excellent in abrasion resistance.
[0088]
Example 10
Chip blend so that P1: P2: P5 = 38: 50: 12 by weight ratio (EBA is 2.0 wt%, carbodiimide group content of PCI is 1.2 times equivalent to carboxyl group terminal content of polylactic acid) Then, a drawn yarn of 84 dtex and 144 filaments was obtained in the same manner as in Example 2 except that the number of die holes was changed to 144 holes. The pack pressure was stable throughout, and there was little smoke immediately below the base. No yarn breakage or fluff was observed, and the spinnability was extremely good. Also, the stretchability was good without a single turn or the like, and no fuzz was attached to the guides.
[0089]
The resulting fiber is b ^* The value was 3.2, which was a good color tone with little yellowness. In addition, the carboxyl group terminal concentration is 5 equivalents / ton or less, which is the detection limit, and η after hot water treatment _r The retention and strength retention were good and showed excellent hydrolysis resistance.
[0090]
Further, the obtained dyed fabric is L ^* Value 37.8, C ^* With a value of 50.8, good red vivid color development was exhibited. The tear strength of the fabric was also excellent at 880 cN.
[0091]
Further, when the rub fastness of the varnish was measured, it was grade 4 and excellent in abrasion resistance.
[0092]
Further, using this dyed fabric, industrial cutting and industrial sewing were performed, but there was no fusion at the cutting portion of the fabric at the time of cutting, and the stain on the sewing needle was very small, showing excellent process passability. . Further, a durability test was carried out by using this to make a shirt and wear it for one month. As a result, there was no fluff, no whitening and no shine, and excellent product durability was shown.
[0093]
Example 11
Chip blending (EBA: 1 wt%, carbodiimide group content of PCI: 0.5 times equivalent to carboxyl group terminal content of polylactic acid) so that P1: P2: P5 = 69: 25: 6 by weight ratio, Except that the spinning temperature was changed to 215 ° C, a drawn yarn of 84 dtex and 36 filaments was obtained in the same manner as in Example 1. The pack pressure was stable throughout, and there was little smoke immediately below the base. No yarn breakage or fluff was observed, and the spinnability was extremely good. In addition, the stretchability was good without a single turn or the like, and no fuzz was attached to the guides.
[0094]
The resulting fiber is b ^* The value was 2.0, indicating a good yellow tone with little yellowness. In addition, the carboxyl group terminal concentration was 8 equivalents / ton, which was slightly inferior to that of Example 1; _r The retention and strength retention were good and showed excellent hydrolysis resistance.
[0095]
Further, the obtained dyed fabric is L ^* Value 9.0, C ^* The value of 1.2 showed good black coloring. The tear strength of the fabric was 780 cN, which was slightly inferior to that of Example 1, but showed excellent fabric characteristics.
[0096]
Further, when the rub fastness of the varnish was measured, it was grade 4 and excellent in abrasion resistance.
[0097]
Example 12
Chip blending (SS is 1 wt%, carbodiimide group content of PCI is 1.2 times equivalent to carboxyl group terminal content of polylactic acid) so that P1: P3: P5 = 63: 25: 12 by weight ratio. Except for the above, a drawn yarn of 84 dtex and 36 filaments was obtained in the same manner as in Example 2. The pack pressure was stable throughout, and there was little smoke immediately below the base. No yarn breakage or fluff was observed, and the spinnability was extremely good. In addition, the stretchability was good without a single turn or the like, and no fuzz was attached to the guides.
[0098]
The resulting fiber is b ^* The value was 3.2, which was a good color tone with little yellowness. In addition, the carboxyl group terminal concentration is 5 equivalents / ton or less, which is the detection limit, and η after hot water treatment _r The retention and strength retention were good and showed excellent hydrolysis resistance.
[0099]
Further, the obtained dyed fabric is L ^* Value 35.0, C ^* The value was 51.8, indicating a good clear color development of red. The tear strength of the fabric was also excellent at 870 cN.
[0100]
Further, when the rub fastness of the varnish was measured, the varnish was grade 3 and excellent in abrasion resistance.
[0101]
Example 13
Chip blending (EBA is 1 wt%, carbodiimide group content of TIC is 1.2 times equivalent to carboxyl group terminal amount of polylactic acid) so that P1: P2: P6 = 60: 25: 15 by weight ratio. Except for the above, a drawn yarn of 84 dtex and 36 filaments was obtained in the same manner as in Example 1. The pack pressure was stable throughout, and there was little smoke immediately below the base. No yarn breakage or fluff was observed, and the spinnability was extremely good. In addition, the stretchability was good without a single turn or the like, and no fuzz was attached to the guides.
[0102]
The resulting fiber is b ^* The value was 2.8, and the color tone was good with little yellowish color. In addition, the carboxyl group terminal concentration is 5 equivalents / ton or less, which is the detection limit, and η after hot water treatment _r The retention and strength retention were good and showed excellent hydrolysis resistance.
[0103]
Further, the obtained dyed fabric is L ^* Value 8.9, C ^* The value of 1.2 showed good black coloring. The tear strength of the fabric was also 900 cN, exhibiting excellent fabric properties.
[0104]
Further, when the rub fastness of the varnish was measured, it was grade 4 and excellent in abrasion resistance.
[0105]
Further, using this dyed fabric, industrial cutting and industrial sewing were performed, but there was no fusion at the cutting portion of the fabric at the time of cutting, and the stain on the sewing needle was very small, showing excellent process passability. . Further, a durability test was carried out by using this to make a shirt and wear it for one month. As a result, there was no fluff, no whitening and no shine, and excellent product durability was shown.
[0106]
Example 14
Chip blending (SS is 1 wt%, carbodiimide group content of TIC is 1.2 times equivalent to carboxyl group terminal amount of polylactic acid) so that P1: P3: P6 = 60: 25: 15 by weight ratio. Except for the above, a drawn yarn of 84 dtex and 36 filaments was obtained in the same manner as in Example 2. The pack pressure was stable throughout, and there was little smoke immediately below the base. No yarn breakage or fluff was observed, and the spinnability was extremely good. In addition, the stretchability was good without a single turn or the like, and no fuzz was attached to the guides.
[0107]
The resulting fiber is b ^* The value was 2.9, indicating a good yellow tone with little yellowness. In addition, the carboxyl group terminal concentration is 5 equivalents / ton or less, which is the detection limit, and η after hot water treatment _r The retention and strength retention were good and showed excellent hydrolysis resistance.
[0108]
Further, the obtained dyed fabric is L ^* Value 33.0, C ^* With a value of 53.5, good red color development was exhibited. The tear strength of the fabric was also excellent at 890 cN.
[0109]
Further, when the rub fastness of the varnish was measured, it was grade 4 and excellent in abrasion resistance.
[0110]
[Table 1]

[0111]
Comparative Example 1
In the same manner as in Example 1 using only P1 (only polylactic acid), a drawn yarn of 84 dtex and 36 filaments was obtained. The pack pressure was stable throughout, and there was little smoke immediately below the mouthpiece. However, thread breakage and fluff occurred, and spinning properties were not very good. Also, the stretchability was not so good due to the occurrence of yarn breakage and fluff.
[0112]
The resulting fiber is b ^* Although the value was 0.5 and the yellowish color was very small and the color tone was good, the carboxyl group terminal concentration was 40 equivalents / ton and the η after hot water treatment was η. _r The retention and strength retention were very poor and poor in hydrolysis resistance.
[0113]
Further, the obtained dyed fabric is L ^* Value 10.2, C ^* Although the value was 1.4, indicating a fair black color development, the tear strength of the fabric was extremely poor at 250 cN. The texture of the fabric was inferior to that of Example 1 because of the mechanical creaking feeling peculiar to the polylactic acid fiber.
[0114]
Further, when the rub fastness of the varnish was measured, it was grade 1 and the abrasion resistance was poor. Further, as a result of observing the surface of the fabric after the friction test with a SEM, the wear of the yarn was remarkable (FIG. 2). In addition, industrial cutting and industrial sewing were performed using this dyed cloth. At the time of cutting, the fusion at the cut section of the cloth was severe, and the stains on the sewing needle were remarkable, resulting in poor processability. Further, a durability test was carried out by using this to make a shirt and wear it for one month. As a result, fluff, whitening and shine were remarkable, and the product durability was poor.
[0115]
Comparative Example 2
A drawn yarn of 84 dtex and 36 filaments was obtained in the same manner as in Example 1 except that chip blending (SA was 1 wt%) was performed so that P1: P4 = 75: 25 in weight ratio. The pack pressure was stable throughout, but there were many smokes just below the mouthpiece, yarn breakage and fluff were generated, and the spinnability was not very good. Also, the stretchability was not so good due to the occurrence of yarn breakage and fluff.
[0116]
The resulting fiber is b ^* The value was 4.2, which was a reasonable color tone, but the carboxyl group terminal concentration was 43 equivalents / ton, and the η after hot water treatment was η. _r The retention and strength retention were very poor and poor in hydrolysis resistance.
[0117]
Further, the obtained dyed fabric is L ^* Value 10.0, C ^* Although the value was 1.4, which was a reasonable level of black color development, the tear strength of the fabric was extremely low at 260 cN. The texture of the fabric was inferior to that of Example 1 because of the mechanical creaking feeling peculiar to the polylactic acid fiber.
[0118]
Further, when the rub fastness of the varnish was measured, it was grade 1 and the abrasion resistance was poor. In addition, industrial cutting and industrial sewing were performed using this dyed cloth. At the time of cutting, the fusion at the cut section of the cloth was severe, and the stains on the sewing needle were remarkable, resulting in poor processability. Further, a durability test was carried out by using this to make a shirt and wear it for one month. As a result, fluff, whitening and shine were remarkable, and the product durability was poor.
[0119]
In addition, when the weight loss rate by heating of SA was calculated | required from TG (thermogravimetry), it turned out that weight loss is reduced 4.1% at 250 degreeC. In contrast, in the case of EBA, which is a fatty acid bisamide, the weight was reduced only by 0.5% at 250 ° C., and it was found that the fatty acid bisamide had better heat resistance and was less likely to sublimate than the fatty acid monoamide.
[0120]
Comparative Example 3
A dyed fabric consisting of a drawn yarn of 84 dtex and 36 filaments was obtained in the same manner as in Comparative Example 2 except that the dyeing method was changed to dyeing method 1 (dyeing temperature: 110 ° C).
[0121]
The resulting dyed fabric had a tear strength of 670 cN, which was a reasonable value. ^* Value 16.0, C ^* The value was 1.6, which was inferior to black color development.
[0122]
Further, when the rub fastness of the varnish was measured, it was grade 1 and the abrasion resistance was poor.
[0123]
In addition, industrial cutting and industrial sewing were performed using this dyed cloth. At the time of cutting, the fusion at the cut section of the cloth was severe, and the stains on the sewing needle were remarkable, resulting in poor processability. Further, a durability test was carried out by using this to make a shirt and wear it for one month. As a result, fluff, whitening and shine were remarkable, and the product durability was poor.
[0124]
Comparative Example 4
84 dtex, 36 filaments in the same manner as in Example 1 except that chip blending (EBA: 1 wt%) was performed so that P1: P2 = 75: 25 by weight ratio, and dyeing method 3 (dyeing temperature: 120 ° C.) was used. Was obtained. The pack pressure was stable throughout, and there was little smoke immediately below the base. No yarn breakage or fluff was observed, and the spinnability was extremely good. In addition, the stretchability was good without a single turn or the like, and no fuzz was attached to the guides.
[0125]
The resulting fiber is b ^* Although the value was 1.2 and the color tone was good with little yellowish taste, the carboxyl group terminal concentration was 41 equivalents / ton, and the η after hot water treatment was η. _r The retention and strength retention were very poor and poor in hydrolysis resistance.
[0126]
In addition, the obtained dyed fabric shows an excellent texture with little mechanical creaking feeling unique to polylactic acid fiber, while being flexible and soft. ^* Value 33.8, C ^* Although the value was 41.0, indicating a fairly vivid blue color development, the tear strength of the fabric was extremely low at 300 cN.
[0127]
The rub fastness of this fabric was grade 4 and excellent in abrasion resistance. Further, using this dyed fabric, industrial cutting and industrial sewing were performed, but there was no fusion at the cutting portion of the fabric at the time of cutting, and the stain on the sewing needle was very small, showing excellent process passability. . Further, a durability test was carried out by using this to make a shirt and wear it for one month. As a result, there was no fluff, no whitening and no shine, and excellent product durability was shown.
[0128]
Comparative Example 5
Chip blending (the amount of carbodiimide group of PCI is 1.2 times equivalent to the amount of terminal carboxyl group of polylactic acid) so that P1: P5 = 88: 12 by weight ratio, and changing the spinning temperature to 245 ° C. A drawn yarn of 84 dtex and 36 filaments was obtained in the same manner as in Example 1 except that Dyeing Method 3 (dyeing temperature: 120 ° C.) was used. Despite the high spinning temperature of 245 ° C., the pack pressure rose with time and was unstable throughout. Immediately below the base, a large amount of smoke was generated due to the thermal decomposition of polylactic acid and PCI. In addition, yarn breakage and fluff occurred, and spinning properties were not so good. Further, the stretchability was not so good due to yarn breakage and fluffing.
[0129]
The resulting fiber has a carboxyl group terminal concentration of 5 equivalents / ton or less, which is below the detection limit, and η after hydrothermal treatment. _r The retention rate and strength retention rate were good and excellent in hydrolysis resistance. ^* The value was 8.9, which was a lot of yellowish color and an inferior color tone.
[0130]
Further, the obtained dyed fabric is L ^* Value 31.0, C ^* Although the value was 33.0, which was reasonably sharp color development, the color was slightly yellowish due to the yellow coloring of the fiber itself. Further, the tear strength was as good as 730 cN, but the texture of this fabric was inferior to that of Example 1 due to the mechanical creaking feeling peculiar to the polylactic acid fiber.
[0131]
Further, when the rub fastness of the varnish was measured, it was grade 1 and the abrasion resistance was poor. In addition, industrial cutting and industrial sewing were performed using this dyed cloth. At the time of cutting, the fusion at the cut section of the cloth was severe, and the stains on the sewing needle were remarkable, resulting in poor processability. Further, a durability test was carried out by using this to make a shirt and wear it for one month. As a result, fluff, whitening and shine were remarkable, and the product durability was poor.
[0132]
Comparative Example 6
Chip blending (the carbodiimide group content of the TIC is 1.2 times equivalent to the carboxyl group terminal content of polylactic acid) so that the weight ratio becomes P1: P6 = 85: 15, and the spinning temperature is changed to 235 ° C. A drawn yarn of 84 dtex and 36 filaments was obtained in the same manner as in Example 1 except that the dyeing method was changed to dyeing method 2 (dyeing temperature 110 ° C.). Despite the high spinning temperature of 235 ° C., the pack pressure increased with time and was unstable throughout. Immediately below the base, a large amount of smoke was generated due to the thermal decomposition of polylactic acid and TIC. In addition, yarn breakage and fluff occurred, and spinning properties were not so good. Further, the stretchability was not so good due to yarn breakage and fluffing.
[0133]
The resulting fiber has a carboxyl group terminal concentration of 5 equivalents / ton or less, which is below the detection limit, and η after hydrothermal treatment. _r The retention rate and strength retention rate were good and excellent in hydrolysis resistance. ^* The value was 7.0, indicating a lot of yellowish color and an inferior color tone.
[0134]
Further, the obtained dyed fabric is L ^* Value 42.3, C ^* Although the value was 33.4, which was a reasonably clear color development of red, the hue was slightly yellowish due to the yellow coloring of the fiber itself. Further, the tear strength was as good as 770 cN, but the texture of this fabric was inferior to that of Example 1 because of the mechanical creaking feeling peculiar to the polylactic acid fiber.
[0135]
Further, when the rub fastness of the varnish was measured, it was grade 1 and the abrasion resistance was poor. In addition, industrial cutting and industrial sewing were performed using this dyed cloth. At the time of cutting, the fusion at the cut section of the cloth was severe, and the stains on the sewing needle were remarkable, resulting in poor processability. Further, a durability test was carried out by using this to make a shirt and wear it for one month. As a result, fluff, whitening and shine were remarkable, and the product durability was poor.
[0136]
[Table 2]

[0137]
【The invention's effect】
According to the present invention, it is possible to provide a polylactic acid fiber which is excellent in abrasion resistance and hydrolysis resistance, has little yellow coloring of the fiber itself, and further has excellent coloring property at the time of dyeing. The range of application development can be greatly expanded.
[Brief description of the drawings]
FIG. 1 is a view showing a worn state of a polylactic acid fiber of the present invention.
FIG. 2 is a view showing a state of wear of a conventional polylactic acid fiber.
FIG. 3 is a diagram showing a spinning device.
FIG. 4 is a view showing a stretching device.
[Explanation of symbols]
1: Hopper
2: Extrusion kneader (extruder)
3: Spin block
4: Spinning pack
5: base
6: Chimney
7: Thread
8: Focusing refueling guide
9: Confounding guide
10: 1st take-up roller
11: Second take-up roller
12: Winding thread
13: undrawn yarn
14: Feed roller
15: 1st hot roller
16: Second hot roller
17: Cold roller
18: drawn yarn

Claims (4)

A polylactic acid fiber containing a fatty acid bisamide and / or an alkyl-substituted fatty acid monoamide, and having a carboxyl group terminal blocked by a carbodiimide compound. The polylactic acid fiber according to claim 1, wherein the b ^* value, which is an index of color tone, is -1 to 6. A fiber structure using the polylactic acid fiber according to claim 1 or 2, which is dyed with a disperse dye, wherein an L ^* value as an index of lightness is 15 or less, and a C ^* value as an index of saturation is not more than 15. Polylactic acid fiber structure characterized by being 8 or less. A fiber structure using the polylactic acid fiber according to claim 1 or 2, which is dyed with a disperse dye, wherein a C ^* value as an index of saturation is 25 or more. object.

Images