JP2004256965A - Method for producing composite false-twist yarn - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for stably producing a new high-quality composite false-twist yarn having excellent color-developing property, bulkiness and soft feeling, free from dyeing speck and exhibiting smooth surface touch. <P>SOLUTION: A spun blended yarn having a birefringence difference of 0.02-0.05 and an elongation difference of 70-200% is produced by blending two kinds of undrawn multifilament yarns produced by spinning a polyester obtained by the polycondensation in the presence of a titanium alkoxide or a reaction product of a titanium alkoxide with an aromatic polybasic carboxylic acid (or its anhydride) and a specific phosphorus compound at a spinning draft difference of 10,000-100,000. The spun blended yarn produced by the method is subjected to simultaneous draw false-twisting treatment with a false twister having a non-contact false twist heat-setting heater at a false twist tension of 0.177-0.353 cN/dtex, a false twist number of (15,000-30,000)/D<SP>1/2</SP>/m and a false twist heater temperature of 200-400°C. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

【００１０】
【化７】

【００１１】
【化８】

【００１２】
【数２】

【００１３】
単一の紡糸口金又は異なる紡糸口金から紡糸ドラフト差１万〜１０万で紡糸された２種類の未延伸ポリエステルマルチフィラメント糸を混繊処理して得た、下記（イ）および（ロ）を同時に満足する紡糸混繊糸を、仮撚の熱セットヒーターが非接触式である仮撚加工機を用いて、下記（ハ）〜（ホ）を同時に満足する条件で延伸同時仮撚加工することを特徴とする複合仮撚加工糸の製造方法により達成できることが見いだされた。
（イ）２種類の未延伸ポリエステルマルチフィラメント糸の複屈折率差（Δｎ）：０．０２≦Δｎ≦０．０５
（ロ）２種類の未延伸ポリエステルマルチフィラメント糸の伸度差（ΔＬ）：７０％≦ΔＬ≦２００％
（ハ）仮撚加撚張力（Ｔ_１）：０．１７７ｃＮ／ｄｔｅｘ≦Ｔ_１≦０．３５３ｃＮ／ｄｔｅｘ
（ニ）仮撚数（Ｋ）：１５０００／Ｄ^１／２回／ｍ≦Ｋ≦３００００）／Ｄ^１／２回／ｍ（ただし、Ｄは複合仮撚加工糸の繊度（ｄｔｅｘ））
（ホ）仮撚ヒータ温度（ＨＡ）：２００℃≦ＨＡ≦４００℃
【００１４】
【発明の実施の形態】
以下、本発明の実施の形態について詳細に説明する。
本発明で用いられる、芳香族ジカルボキシレートエステルを重縮合して得られるポリエステルの重縮合用触媒としては、上記式（Ｉ）で表されるチタンアルコキシド及び上記式（Ｉ）で表されるチタンアルコキシドと上記式（ＩＩ）で表される芳香族多価カルボン酸又はその無水物とを反応させた生成物からなる群から選ばれた少なくとも一種のチタン化合物を用いる。
【００１５】
該チタンアルコキシドとしては、具体的には、チタンテトラブトキシド、チタンテトライソプロポキシド、チタンテトラプロポキシド、チタンテトラエトキシドに例示されるチタンテトラアルコキシド、オクタアルキルトリチタネート、ヘキサアルキルジチタネートなどを挙げることができ、なかでもチタンテトラアルコキシドが好ましく、特にチタンテトラブトキシドが好ましい。
【００１６】
また、該チタンアルコキシドと反応させる一般式（ＩＩ）で表される芳香族多価カルボン酸又はその無水物としては、フタル酸、トリメリット酸、ヘミメリット酸、ピロメリット酸及びこれらの無水物が好ましく用いられる。
【００１７】
上記チタンアルコキシドと芳香族多価カルボン酸又はその無水物とを反応させる条件は特に限定する必要はなく、例えば、適当な溶媒に芳香族多価カルボン酸又はその無水物の一部又は全部を溶解し、この溶液中にチタンアルコキシドを滴下し、０〜２００℃の温度で少なくとも３０分間、好ましくは３０〜１５０℃の温度で４０〜９０分間加熱すればよい。この際、反応圧力も特に制限はなく、常圧で十分である。なお、芳香族多価カルボン酸又はその無水物を溶解させる溶媒としては、エタノール、エチレングリコール、トリメチレングリコール、テトラメチレングリコール、ベンゼン、キシレン等、所望に応じて任意の溶媒を適宜選択して用いればよい。
【００１８】
ここで、チタンアルコキシドと芳香族多価カルボン酸又はその無水物との反応モル比も特に限定する必要はないが、芳香族多価カルボン酸又はその無水物の割合が少なくなりすぎると、得られるポリエステルの色調改善効果が小さくなり、逆に多くなりすぎると重縮合反応が進みにくくなる場合がある。このため、チタンアルコキシドと芳香族多価カルボン酸又はその無水物との反応モル比は、２／１〜２／５の範囲内とすることが好ましい。
【００１９】
本発明におけるポリエステルは、上記のチタン化合物に加えて、上記式（ＩＩＩ）で表されるリン化合物の存在下で、芳香族ジカルボキシレートエステルを重縮合することにより得られるものである。好ましく用いられる該リン化合物（ホスホネート化合物）としては、カルボメトキシメタンホスホン酸、カルボエトキシメタンホスホン酸、カルボプロポキシメタンホスホン酸、カルボブトキシメタンホスホン酸、カルボメトキシフェニルメタンホスホン酸、カルボエトキシフェニルメタンホスホン酸、カルボプロポキシフェニルメタンホスホン酸、カルボブトキシフェニルメタンホスホン酸等のホスホン酸誘導体のジメチルエステル類、ジエチルエステル類、ジプロピルエステル類、ジブチルエステル類等から選ばれることが好ましい。
【００２０】
このようなホスホネート化合物は、通常ポリエステルの重縮合反応時に安定剤として使用されるリン化合物と比較すると、前記チタン化合物との反応がより緩やかに進行するため、反応中における該チタン化合物の触媒活性持続時間が長くなり、結果として該チタン化合物の存在量を少なくすることができる。また、前記チタン化合物に対して該ホスホネート化合物を比較的多量に用いても、得られるポリエステルの熱安定性を低下させることがなく、その色調も悪化させることもない。
【００２１】
このように重縮合して得られる本発明にかかるポリエステルは、チタン金属元素濃度及びリン元素濃度が、下記数式（１）及び（２）を同時に満足する必要がある。
【００２２】
【数３】

【００２３】
ここで、（Ｐ／Ｔｉ）が１未満の場合には、重縮合時に着色が進み、得られるポリエステルの色相が黄味を帯びたものとなるので好ましくない。一方、（Ｐ／Ｔｉ）が１５を越える場合には、ポリエステルの重縮合反応性が大幅に低下するため、目的とするポリエステルを得ることが困難となる。
【００２４】
また、（Ｔｉ＋Ｐ）が１０未満の場合には、製糸工程における生産性が大きく低下するため、満足な性能を有する繊維が得られなくなるので好ましくない。一方、（Ｔｉ＋Ｐ）が１００を越える場合には、重縮合反応時に、触媒に起因する異物が少量ではあるが発生しているので好ましくない。
【００２５】
なお、前記（１）式の（Ｐ／Ｔｉ）は２〜１５の範囲が好ましく、特に４〜１０の範囲が好ましい。また、（２）式の（Ｔｉ＋Ｐ）は２０〜７０の範囲がより好ましい。
【００２６】
また、Ｔｉ金属元素濃度は、ポリエステルの全酸成分を基準として２〜１５ミリモル％の範囲が適当である。
【００２７】
本発明で用いられているポリエステルは、上記のチタン化合物とリン化合物との存在下に芳香族ジカルボキシレートエステルを重縮合して得られるものであるが、該芳香族ジカルボキシレートエステルは、芳香族ジカルボン酸と脂肪族グリコールとからなるジエステルであることが好ましい。
【００２８】
ここで芳香族ジカルボン酸は、テレフタル酸を主とすることが好ましい。より具体的には、テレフタル酸が全芳香族ジカルボン酸を基準として７０モル％以上、なかでも８０モル％以上を占めていることが好ましい。ここでテレフタル酸以外の好ましい芳香族ジカルボン酸としては、例えば、フタル酸、イソフタル酸、ナフタレンジカルボン酸、ジフェニルジカルボン酸、ジフェノキシエタンジカルボン酸等を挙げることができる。
【００２９】
また、脂肪族グリコールはアルキレングリコールが好ましく、具体的には、エチレングリコール、トリメチレングリコール、プロピレングリコール、テトラメチレングリコール、ネオペンチルグリコール、ヘキサンメチレングリコール、ドデカメチレングリコール等を例示することができる。なかでも、エチレングリコールが好ましい。
【００３０】
なかでも、全繰り返し単位の７０モル％以上がエチレンテレフタレートからなるポリエステルが好ましく、特にポリエチレンテレフタレートが好ましい。
【００３１】
本発明にかかるポリエステルは、上記の芳香族ジカルボン酸と脂肪族グリコール以外の酸成分又はジオール成分が、少なくとも１種共重合された共重合ポリエステルであってもよい。
【００３２】
好ましく用いられる共重合成分としては、酸成分として、アジピン酸、セバシン酸、アゼライン酸、デカンジカルボン酸などの脂肪族ジカルボン酸、シクロヘキサンジカルボン酸などの脂環式ジカルボン酸などの二官能性カルボン酸をあげることができる。また、ジオール成分として、シクロヘキサンジメタノールなどの脂環式グリコール、ビスフェノール、ハイドロキノン、２，２−ビス（４−β−ヒドロキシエトキシフェニル）プロパン類などの芳香族ジオールなどをあげることができる。
【００３３】
さらに、トリメシン酸、トリメチロールエタン、トリメチロールプロパン、トリメチロールメタン、ペンタエリスリトールなどの多官能性化合物を、得られるポリエステルが実質上線状である範囲で少量共重合したものであってもよい。
【００３４】
本発明においては、上記の芳香族ジカルボン酸と脂肪族グリコールとからなる芳香族ジカルボキシレートエステルが用いられるが、該芳香族ジカルボキシレートエステルは、芳香族ジカルボン酸と脂肪族グリコールとのジエステル化反応によって得てもよいし、芳香族ジカルボン酸のジアルキルエステルと脂肪族グリコールとのエステル交換反応により得てもよく、その製造方法は任意である。しかしながら、後者のエステル交換反応による方法の方が、前者のジエステル化反応による方法よりも、重縮合反応中に存在させる前記リン化合物の飛散がより少なくなるので好ましい。
【００３５】
なお、前記チタン化合物の一部及び／又は全量を、該エステル交換反応開始前に添加し、エステル交換反応触媒と重縮合反応触媒との両反応の触媒として兼用させることが好ましい。このようにすることにより、得られるポリエステル中の金属触媒の含有量を低減することができる。
【００３６】
以下、ポリエチレンテレフタレートを例として、好ましい態様をさらに具体的に説明する。まず、テレフタル酸のジアルキルエステルとエチレングリコールとのエステル交換反応を、前記一般式（Ｉ）で表されるチタンアルコキシド、及び、該チタンアルコキシドと前記一般式（ＩＩ）で表される芳香族多価カルボン酸又はその無水物とを反応させた生成物からなる群から選ばれた少なくとも１種のチタン化合物の存在下に行う。得られたテレフタル酸とエチレングリコールとのジエステルを含有する反応混合物に、さらに前記一般式（ＩＩＩ）で表されるリン化合物を添加し、これらの存在下に重縮合する。
【００３７】
なお、該エステル交換反応は、通常常圧下で実施されるが、０．０５〜０．２０ＭＰａの加圧下に実施すると、チタン化合物の触媒作用による反応がさらに促進され、かつジエチレングリコールの副生も低減するので、得られるポリエステルの熱安定性などの特性が良好となるので好ましい。温度は１６０〜２６０℃の範囲が適当である。
【００３８】
次に、前記チタン化合物とリン化合物との存在下に、上記で得られたエチレングリコールエステル又はその低重合体を、減圧下で、得られるポリエステルの融点以上分解点未満の温度（通常２４０℃〜２８０℃）に加熱することにより重縮合させる。この重縮合反応では、未反応のエチレングリコール及び重縮合で発生するエチレングリコールを反応系外に留去させながら行うことが望ましい。
【００３９】
重縮合反応は、１槽で行ってもよく、複数の槽に分けて行ってもよい。例えば、重縮合反応が２段階で行われる場合には、第１槽目の重縮合反応は、反応温度が２４５〜２９０℃、好ましくは２６０〜２８０℃、圧力が１００〜１ｋＰａ、好ましくは５０〜２ｋＰａの条件下で行われ、最終第２槽での重縮合反応は、反応温度が２６５〜３００℃、好ましくは２７０〜２９０℃、反応圧力は通常１０〜１０００Ｐａで、好ましくは３０〜５００Ｐａの条件下で行われる。
【００４０】
本発明で用いられるポリエステルは、上記のようにして製造することができるが、得られたポリエステルは、通常、粒状（チップ状）にされる。なお、得られるポリエステルの固有粘度は０．４０〜０．８０、好ましくは０．５０〜０．７０であることが望ましい。所望により、固相重縮合によりさらに固有粘度をあげても構わない。
【００４１】
該固相重縮合工程に供給される粒状ポリエステルは、予め、固相重縮合を行う場合の温度より低い温度に加熱して予備結晶化を行った後、固相重縮合工程に供給してもよい。
【００４２】
このようにして得られる本発明にかかるポリエステルは、必要に応じて少量の添加剤、例えば滑剤、顔料、染料、酸化防止剤、固相重合促進剤、蛍光増白剤、帯電防止剤、抗菌剤、紫外線吸収剤、光安定剤、熱安定剤、遮光剤、艶消剤等を含んでいてもよい。なかでも艶消剤としての酸化チタン、安定剤としての酸化防止剤は好ましく添加され、通常酸化チタンは、平均粒径が０．０１〜２μｍのものを、最終的に得られるポリエステル組成物中に占める割合が０．０１〜１０重量％となるように添加される。
【００４３】
また、酸化防止剤としては、ヒンダードフェノール系の酸化防止剤が好ましく添加される。該ヒンダードフェノール系酸化防止剤の添加量は、通常１重量％以下とされる。１重量％を越える場合には製糸時にスカム発生の要因となるだけでなく、１重量％を越えて添加しても溶融安定性向上の効果が飽和してしまう。かかる酸化防止剤の添加量は０．００５〜０．５重量％の範囲が特に好ましい。なお、ヒンダードフェノール系酸化防止剤に加えて、チオエーテル系二次酸化防止剤を併用することがさらに好ましい。
【００４４】
これらの酸化防止剤のポリエステルへの添加方法は特に制限されないが、好ましくはエステル交換反応又はエステル化反応終了後であって、重合反応が完了するまでの間の任意の段階で添加する。
【００４５】
本発明においては、上記のポリエステルを、単一の又は異なる紡糸口金を用いて、紡糸ドラフト差が１万〜１０万の範囲内で紡糸された下記（イ）及び（ロ）を同時に満足する２種類の配向差を有する未延伸ポリエステルマルチフィラメント糸を得、これを混繊処理、好ましくは混繊交絡処理して得た紡糸混繊糸を、延伸同時仮撚加工に供する必要が有る。
（イ）２種類の未延伸ポリエステルマルチフィラメント糸の複屈折率差（Δｎ）：０．０２≦Δｎ≦０．０５、好ましくは０．０２５≦Δｎ≦０．０４５
（ロ）２種類の未延伸ポリエステルマルチフィラメント糸の伸度差（ΔＬ）：７０％≦ΔＬ≦２００％、好ましくは９０％≦ΔＬ≦１８０％
【００４６】
ここで、紡糸ドラフト差が１万未満の場合には、未延伸マルチフィラメント糸間の伸度差（ΔＬ）が小さくなって得られる仮撚捲縮加工糸はバラケ気味になり、バルキ−不足となって目標とする加工糸の風合が得られない。一方、紡糸ドラフト差が１０万を越える場合には、高紡糸ドラフト成分の紡糸性が悪化するだけでなく、仮撚加工時に断糸や毛羽の発生が多くなるので好ましくない。
【００４７】
また、上記紡糸ドラフト差を有する２種類の未延伸ポリエステルマルチフィラメント糸は、その伸度差（ΔＬ）が上記の範囲となるように紡糸ドラフト差をさらに調整設定することが大切で、この伸度差が７０％未満では得られる加工糸の嵩高性が不十分となり、一方２００％を越える場合には、カスリ斑が発生しやすくなるので好ましくない。
【００４８】
また、２種類の未延伸ポリエステルマルチフィラメント糸の複屈折率差（Δｎ）は上記の範囲内であることが、仮撚加工時の加撚張力を適正化してサージング発生を防止する上で大切で、この複屈折率差が０．０２未満ではサージング発生による熱セット斑に起因して染斑が大きくなる。一方、０．０５を越える場合には、繊維断面形状の不均一化、断糸、毛羽などが多くなるので好ましくない。
【００４９】
なお、これら未延伸ポリエステルマルチフィラメント糸のトータル繊度比は、５：５〜３：７（芯部：鞘部）と鞘部になる部分が多いほうが好ましく、トータル繊度は仮撚加工後の繊度で７５〜３３０ｄｔｅｘの範囲が好ましい。また、夫々の単糸繊度は、仮撚加工後で、芯糸となる高ドラフト側が３０〜１３０ｄｔｅｘ、鞘糸になる低ドラフト側が４０〜２００ｄｔｅｘとなるようにするのが好ましい。
【００５０】
このようなドラフト差を有する未延伸糸は、孔径差を適当な値に設定した異なる２種の吐出孔群からポリエステルを溶融吐出し、これを例えば８００〜４０００ｍ／分、好ましくは１０００〜２０００ｍ／分、特に好ましくは１０００〜１５００ｍ／分の速度で引取ることにより容易に得ることができる。
【００５１】
上記の未延伸糸の混繊処理は、引取りローラーの前の段階で行っても、引取りローラーを通過した後の段階で行ってもよい。混繊処理方法は特に限定されず、従来公知の方法を適宜選定すればよいが、例えばインターレースノズルを用いて圧空処理して混繊交絡させる方法が好ましい。この際の交絡数は、多すぎると毛羽が多くなる傾向があり、一方少なすぎると混繊不良に起因してカスリ斑になる傾向があるので１０〜７０個／ｍの範囲が適当である。
【００５２】
本発明においては、上述の要件を満足する紡糸混繊糸を、仮撚の熱セットヒーターが非接触式である仮撚加工機を用い、下記（ハ）〜（ホ）を同時に満足するよう延伸倍率等の仮撚加工条件を設定して延伸同時仮撚加工する必要がある。
（ハ）仮撚加撚張力（Ｔ_１）：０．１７７ｃＮ／ｄｔｅｘ≦Ｔ_１≦０．３５３ｃＮ／ｄｔｅｘ、好ましくは０．２２１ｃＮ／ｄｔｅｘ≦Ｔ_１≦０．３０９ｃＮ／ｄｔｅｘ
（ニ）仮撚数（Ｋ）：１５０００／Ｄ^１／２回／ｍ≦Ｋ≦３００００）／Ｄ^１／２回／ｍ（ただし、Ｄは複合仮撚加工糸の繊度（ｄｔｅｘ））、好ましくは２００００／Ｄ^１／２回／ｍ≦Ｋ≦２５０００）／Ｄ^１／２回／ｍ
（ホ）仮撚ヒータ温度（ＨＡ）：２００℃≦ＨＡ≦４００℃、２５０℃≦ＨＡ≦３５０℃
ここで、加撚張力が上記範囲未満の場合には、サージングが発生しやすくなって染め斑が増大するので好ましくなく、一方、該範囲を越える場合には、毛羽の発生が増大し、また断糸も発生しやすくなるので好ましくない。なお、解撚張力は、低すぎると染斑不良（スポット未解撚状）になりやすく、一方高すぎると毛羽が多発しやすいので、０．０８８〜０．２６５ｃＮ／ｄｔｅｘの範囲とするのが望ましい。
【００５３】
次に、仮撚数（回／ｍ）が１５０００／Ｄ^１／２回／ｍ未満の場合には、風合が硬く、フラットヤーンライクとなるので好ましくなく、一方、３００００／Ｄ^１／２回／ｍを超える場合には、断糸や毛羽が急激に発生しやすくなるので好ましくない。
【００５４】
また、仮撚ヒータ温度（ＨＡ（ＨＡ：熱セットヒーター温度）が２００℃未満の場合には、得られる複合加工糸の鞘部に配される糸の糸条長手方向における斑（熱セット不足による染斑）が発生しやすく、また嵩高性も不足して、本発明の目的を達成することができない。一方、４００℃を越える場合には、ソフト感が不十分となって、やはり本発明の目的を達成することができない。
【００５５】
なお仮撚加工後に再熱処理する場合においては、糸のオーバーフィード率は０〜８％の範囲が好ましく、０％未満（すなわち伸長）では得られる複合仮撚加工糸のバルキー性が低下する傾向にあり、一方８％を越える場合では得られる複合仮撚加工糸のループが大きくなって品位が低下する傾向にある。
【００５６】
次に、図１は上記本発明の製造方法における一実施態様を示す概略工程図である。図１において、予め紡糸混繊交絡処理されたドラフト差を有する２種の未延伸ポリエステルマルチフィラメント糸は、ガイド２を経てフィードローラー３により延伸同時仮撚域に供給される。次いで、フィードローラー３と第１デリベリーローラー８との間で延伸されながらフリクションディスク７により加撚・解撚され、その際第１仮撚熱セットヒーター５で熱固定される。仮撚加工された糸条は、必要に応じて第１デリベリーローラー８と第２デリベリーローラー１０との間で再熱処理ヒーター９で再熱処理され、次いで巻取ローラー１１でパッケージ１２として巻き取られる。
【００５７】
【作用】
以上に詳述した本発明の複合仮撚加工糸の製造方法では、特定のチタン化合物とリン化合物との存在下に重縮合して得られるポリエステルを用い、紡糸ドラフト差を与えて溶融紡糸した２種の未延伸糸からなる紡糸混繊糸を用いているので、発色性、嵩高感、ソフト感に優れ、カスリ斑がなく、且つ、滑らかな表面タッチの風合を呈する新規で高品質の複合仮撚加工糸が、長期にわたり連続的に安定して生産することができる。
【００５８】
【実施例】
以下、実施例により、本発明をさらに具体的に説明する。なお、実施例、比較例における各特性値の測定は下記方法により行った。
【００５９】
（１）チタン金属元素含有量、リン元素含有量
粒状のポリエステル試料をアルミ板上で加熱溶融した後、圧縮プレス機で平坦面を有する試験成型体を作成し、理学電気工業株式会社製蛍光Ｘ線測定装置３２７０Ｅを用いてチタン金属元素含有量およびリン元素含有量を測定した。
【００６０】
ただし、艶消し剤として酸化チタンを添加したポリマー中のチタン原子濃度については、サンプルをヘキサフルオロイソプロパノールに溶解し、遠心分離機で前記溶液から酸化チタン粒子を沈降させ、傾斜法により上澄み液のみを回収し、溶剤を蒸発させて供試サンプルを調整し、このサンプルについて測定した。
【００６１】
（２）固有粘度
オルソクロロフェノールを溶媒とし、常法にしたがい温度３５℃で測定した。
【００６２】
（３）複屈折率
常法にしたがい、光学顕微鏡とコンペンセーターを用いて、繊維の表面に観察される偏光のリターデーションから求めた。
【００６３】
（４）口金異物高さ
各実施例に示す方法、条件で溶融紡糸を行い、３、６、９日後に紡糸口金表面に離型剤を吹き付けて、吐出ポリマーが付着しないようにして紡糸口金を取り外し、顕微鏡にて吐出孔周辺に付着・堆積した口金異物の高さを測定した。全ての吐出孔について口金異物の高さを測定し、それらの平均値で表した。
【００６４】
（５）紡糸断糸率
人為的または機械的要因に起因する断糸を除き、紡糸機運転中に発生した紡糸断糸回数を記録し下記式で紡糸断糸率（％）を計算した。
紡糸断糸率（％）＝［断糸回数／（稼動ワインダー数×ドッフ数）］×１００
ここで、ドッフ数とは未延伸糸パッケージを既定量（１０ｋｇ）まで捲き取った回数をいう。
【００６５】
（６）毛羽個数
東レ（株）製ＤＴ−１０４型毛羽カウンター装置を用いて、延伸仮撚加工糸を５００ｍ／ｍｉｎの速度で２０分間連続測定して発生毛羽数（個／１０^４ｍ）をカウントした。
【００６６】
（７）延伸仮撚断糸率
人為的または機械的要因に起因する断糸を除き、延伸仮撚機運転中に発生した断糸回数を記録し下記式で延伸仮撚断糸率（％）を計算した。
延伸仮撚断糸率（％）＝［断糸回数／（稼動錘数×ドッフ数）］×１００
ここで、ドッフ数とは仮撚加工糸パッケージを既定量（２．５ｋｇ）まで捲き取った回数をいう。
【００６７】
（８）（Ｌ^＊−ｂ^＊）値
ポリエステル繊維を１２ゲージ丸編機で３０ｃｍ長の筒編みとし、ミノルタ株式会社社製ハンター型色差計ＣＲ−２００を用い、Ｌ^＊値、ｂ^＊値を測定し、その差を（Ｌ^＊−ｂ^＊）値とした。
【００６８】
（９）強度・伸度
ＪＩＳ−Ｌ１０１３に準拠して測定した。
【００６９】
（１０）＜紡糸ドラフト＞
引取速度（Ｓ）とポリマーの吐出線速度（Ｔ）の比（Ｓ／Ｔ）を算出した。
【００７０】
（１１）未延伸ポリエステルマルチフィラメントの切断伸度
ＪＩＳ Ｌ―１０１３―７５に準じて測定した。
【００７１】
（１２）捲縮率（ＴＣ）
複合仮撚加工糸に０．０４４ｃＮ／ｄｔｅｘの張力を掛けてカセ枠に巻き取り、約３３００ｄｔｅｘのカセを作る。カセ作成後、カセの一端に０．００１７７ｃＮ／ｄｔｅｘ＋０．１７７ｃＮ／ｄｔｅｘの荷重を負荷し、１分間経過後の長さＬ_０（ｃｍ）を測定する。次いで、０．１７７ｃＮ／ｄｔｅｘの荷重を除去した状態で、１００℃の沸水中にて２０分間処理する。沸水処理後０．００１７７ｃＮ／ｄｔｅｘの荷重を除去し、２４時間自由な状態で自然乾燥する。自然乾燥した試料に、再び０．００１７７ｃＮ／ｄｔｅｘ＋０．１７７ｃＮ／ｄｔｅｘの荷重を負荷し、１分間経過後の長さＬ_１（ｃｍ）を測定する。次いで、０．１７７ｃＮ／ｄｔｅｘの荷重を除去し、１分間経過後の長さＬ_２を測定し、次の算式で捲縮率を算出した。この測定を１０回実施し、その平均値で表した。
ＴＣ（％）＝［（Ｌ_１−Ｌ_２）／Ｌ_０］×１００
【００７２】
（１３）複合仮撚加工糸の風合
得られた複合仮撚加工糸を筒編機にて編立て、常法にしたがって精練、染色、ファイナルセットした後の編地の風合（ソフト感）及び表面タッチを総合して、熟練者５人により官能判定した。判定は１（不良）×〜３○（極めて良好）の３段階で表し、２以上を合格レベルとした。
【００７３】
（１４）嵩高性
複合仮撚加工糸を綛（周長１．２５ｍ）に３２０回転とり、２つ折りにしたサンプルの一端に５．８８ｃＮ（６．０ｇ）の荷重を吊るし、乾熱１８０℃下で５分間熱処理し、冷却後一定の重量（Ｗｇ）の体積（Ｖｃｍ^３）を６．４ｇの荷重下で測定し以下の式で算出した。
嵩高性（ｃｍ^３／ｇ）＝Ｖ／Ｗ
【００７４】
（１５）沸水収縮率（ＢＷＳ）
約３３００ｄｔｅｘの複合仮撚加工糸のカセを作り、これに０．０８８３ｃＮ／ｄｔｅｘの荷重をかけて原長Ｌ_０（ｃｍ）を測定し、次にカセの荷重を０．００１７７ｃＮ／ｄｔｅｘに変え、これを沸水中で３０分間熱処理し、次いで室温で乾燥させた後、荷重を０．０８８３ｃＮ／ｄｔｅｘに変えてその長さＬ_１（ｃｍ）を測定し、次の算式で算出し、１０回測定してその平均値を求めた。
沸水収縮率（ＢＷＳ）＝（Ｌ_０−Ｌ_１）／Ｌ_０×１００
【００７５】
［実施例１〜３、比較例１］
ポリエステル中に含有されるチタン金属元素量（Ｔｉ）及びリン元素濃度（Ｐ）が各々表１に記載の量となる割合で、トリメリット酸チタン及びトリエチルホスホノアセテートを用い、テレフタル酸ジメチルとエチレングリコールとを重縮合して、固有粘度０．６３０のポリエチレンテレフタレートを得た。
【００７６】
得られたポリエチレンテレフタレートペレットを１５０℃で５時間乾燥した後、スクリュウー式押出機を装備した溶融紡糸設備にて溶融し、２９５℃のスピンブロックに導入し、紡糸口金からドラフト差７．７万で吐出し、ポリマー流をクロスフロー式の送風筒から噴出される空気流で冷却・固化しつつ、紡糸口金から８０ｃｍ下方に設置された計量ノズル式給油装置で、給油しながら集束し、エアーノズルで交絡処理を施した後に１３００ｍ／分の速度で引き取り、３００ｄｔｅｘ／７２ｆｉｌ（高紡糸ドラフト成分：１２０ｄｔｅｘ／２４ｆｉｌ、低紡糸ドラフト成分：１８０ｄ／４８ｆｉｌで、複屈折率差０．０２５、切断伸度差１５０％、交絡数２５個／ｍ）の未延伸混繊糸として、１０ｋｇをパッケージ状に巻き取った。上記溶融紡糸操作は９日間連続して行った。
【００７７】
次に、得られたポリエステル未延伸混繊糸パッケージを、図１に示した装置で延伸同時仮撚加工を行った。すなわち、直径５８ｍｍのウレタンディスクを仮撚具として装備した帝人製機株式会社製ＨＴＳ−１５００型延伸仮撚加工機にて、延伸倍率１．８０、仮撚ヒーター温度３００℃、延伸仮撚速度７００ｍ／ｍｉｎの延伸仮撚条件で延伸仮撚加工を行い１７０ｄｔｅｘ／７２ｆｉｌの複合仮撚加工糸を得た。なお、１０ｋｇ捲の未延伸パッケージから２．５ｋｇ捲の仮撚加工糸パッケージを４個作成する方法で延伸仮撚加工を行った。
【００７８】
その際の加撚張力（Ｔ_１）は４９ｃＮ（０．２５６ｃＮ／ｄｔｅｘ）、解撚張力（Ｔ_２）は３７．２ｃＮとし、７００ｍ／分の速度で加工した。得られた複合仮撚加工糸は、嵩高性は３６ｃｍ^３／ｇと極めて嵩高性の大きいものであった。
【００７９】
得られた複合仮撚加工糸を筒編に編立て、常法にしたがって染色、仕上げした編地は、サラットした滑らかな表面タッチで且つソフトな風合を呈するものであった。またこの仮撚加工糸に１８００Ｔ／ｍの撚糸を施し、経密度が１７６本／３．７９ｃｍ、緯密度が１０６本／３．７９ｃｍの綾組織に織成し、常法にしたがって、リラックス（温度１２０℃、２０分間）、プレセット（温度１８０℃、４５秒）、アルカリ減量処理（減量率１７％）、染色加工（温度１３０℃、４５分間）、およびファイナルセット（温度１６０℃、４５秒間）の工程をとおして織物を得た。得られた織物は、滑らかな表面タッチと優れたドレープ性を呈した優れた織物であった。得られた結果を表１にまとめて示す。
【００８０】
［比較例２］
テレフタル酸のエチレングリコールジエステルを、３酸化アンチモン（Ｓｂ_２Ｏ_３）を触媒として常法により重縮合し、固有粘度０．６３０のポリエチレンテレフタレートを得る以外は実施例１と同様にした。結果を表１に示す。
【００８１】
なお、本比較例では、表１に示したように、紡糸時間の経過にともない口金異物が急速に成長し、吐出糸条の屈曲、ピクツキ及び旋回が増加するにしたがい、紡糸断糸の急激な増加が認められ、紡糸３日経過後には紡糸断糸が多発して、正常な紡糸操作が困難となったので運転を中止した。
【００８２】
【表１】

【００８３】
［比較例３］
実施例１で得たポリエチレンテレフタレートを、紡糸ドラフト１５６、紡糸速度１３００ｍ／分で紡糸して伸度３６０％、複屈折率０．０１５、１６７ｄｔｅｘ／４８フィラメントの低配向未延伸ポリエステルマルチフィラメントを得た。また別に、紡糸ドラフト１８８、紡糸速度３２００ｍ／分で紡糸して伸度１２５％、複屈折率０．０４５、１３８ｄｔｅｘ／２４フィラメントの高配向未延伸ポリエステルフィラメントを得た。
【００８４】
両フィラメントを引き揃え、混繊交絡処理（交絡数５０個／ｍ）した後に、延伸倍率１．６３、仮撚温度２００℃の下、仮撚具として三軸フリクションディスクを用い、加撚張力（Ｔ_１）７３．５ｃＮ（０．３８９ｃＮ／ｄｔｅｘ）、解撚張力（Ｔ_２）４９ｃＮとして４００ｍ／分の速度で加工し、１８８ｄｔｅｘ／７２ｆｉｌの複合仮撚加工糸を得た。得られた仮撚加工糸の嵩高性は１９ｃｍ^３／ｇと低いものであった。
【００８５】
この複合仮撚加工糸を、実施例１と同様に処理して織物となしたところ、得られた織物は表面タッチがザラザラとしていて、風合が劣ったものであった。
【００８６】
［実施例４〜１４、比較例４〜１１］
実施例１において、紡糸ドラフト差、複屈折率差および伸度差を表２に記載のとおり変更した以外は同様にして複合仮撚加工糸を得た。結果をまとめて表２に示す。また、比較例３も合わせて示す。
【００８７】
また、実施例１において、仮撚条件を表３または４に記載のとおり変更した以外は、実施例１と同様にして複合仮撚加工糸を得た。これらの結果はそれぞれ表３および４に示す。
【００８８】
【表２】

【００８９】
【表３】

【００９０】
【表４】

【００９１】
【発明の効果】
本発明によれば、発色性、嵩高感、ソフト感に優れ、しかもカスリ斑等の染色斑が発生し難く、且つ滑らかな表面タッチの風合を呈する二層構造の複合仮撚加工糸を長期間安定して得ることができる。
【図面の簡単な説明】
【図１】実施例１で使用した複合仮撚加工糸を製造する装置の概略図である。
【符号の説明】
１ ポリエステル混繊糸
２ ガイド
３ フィードローラー
４ インターレースノズル
５ 熱セットヒーター（仮撚温度）
６ 冷却プレート
７ 撚掛装置（仮撚ディスク）
８ 第１デリベリーローラー
９ 再熱処理ヒーター（再熱処理温度）
１０ 第２デリベリーローラー
１１ 巻取ローラー
１２ パッケージ[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention is capable of stably producing a new, high-quality composite false-twisted yarn having excellent coloring properties (dense dyeing properties), excellent softness, no shaving spots, and a smooth surface touch feeling. It is about how you can do it. More specifically, the present invention relates to a method for producing a composite false twisted yarn having a two-layer structure in which a sheath yarn is wound around a core yarn along the longitudinal direction of a filament.
[0002]
[Prior art]
Conventionally, a method is known in which two or more filament yarns having a difference in elongation are aligned, entangled, and subsequently false-twisted to obtain a bulky, double-layered composite false-twisted yarn having an excellent warm feeling. (For example, Japanese Patent Publication No. 60-11130, Japanese Patent Publication No. 61-19733). However, although these two-layer yarns are excellent in span feeling and bulkiness, they exhibit strong crimping due to false twist, strong rough stiffness due to cross-sectional deformation, and exhibit a unique slimy feeling. For this reason, there is a problem that it cannot sufficiently cope with applications requiring a rayon-like feeling such as outerwear for midsummer and a refreshing feeling with a slat. Furthermore, in the above-mentioned conventional method, since the false twisting process is usually performed after the yarns having different finenesses are separately spun and aligned and entangled, the productivity is low, and uneven spots are easily generated due to non-uniform fiber mixing. In addition, there was a drawback that the feeling was not sufficiently satisfactory.
[0003]
On the other hand, in recent years, an application of a technique of mixing and entangled two or more filament yarns in a spinning process has been attempted. For example, a method of using a cooling difference by varying the die surface depth (Japanese Patent Application Laid-Open No. 60-252711), a method of using a spinneret having a discharge hole whose cross-sectional area continuously increases, and applying a high draft (particularly). Japanese Unexamined Patent Publication (Kokai) No. 4-194007) and a method utilizing the above-described combination of cooling difference and high draft (Japanese Unexamined Patent Publication (Kokai) No. 4-194010) have been proposed. However, even if these false-twisted yarns are subjected to normal false twisting, there is a problem that the feeling of bulkiness is insufficient, processed fluff is likely to occur, and the softness of the woven fabric is still insufficient. there were.
[0004]
In order to solve such a problem, Japanese Patent Application Laid-Open No. 2000-136455 proposes a method for producing a composite false twisted yarn in which a mixed spun yarn utilizing draft difference is stretched and false twisted under specific conditions. ing. Certainly, according to this method, although a double-layered composite false twisted yarn having an excellent soft feeling, hardly causing stain spots such as scum spots, and exhibiting a smooth surface touch feeling can be obtained, a normal twisted yarn is obtained. When spinning polyester, especially polyethylene terephthalate, foreign substances (sometimes referred to as spinnerets) are deposited and deposited around the spinneret discharge hole with the lapse of spinning time due to the antimony catalyst present in the polyester. In addition, there is a problem that not only cannot the yarn be stably spun, but also the quality of the finally obtained composite false twisted yarn is deteriorated.
[0005]
Although the problem caused by such an antimony compound is reduced by using a titanium compound such as titanium tetrabutoxide, the yellowness of the polyester itself becomes stronger, and the resulting composite false-twisted yarn has reduced color developability and is used for clothing. Has the problem that it cannot be used.
[0006]
[Patent Document 1]
Japanese Patent Publication No. 60-11130 [Patent Document 2]
JP-B-61-19733 [Patent Document 3]
JP-A-60-252711 [Patent Document 4]
JP-A-4-194007 [Patent Document 5]
JP-A-4-194010 [Patent Document 6]
JP 2000-136455 A
[Problems to be solved by the invention]
The present invention has been made on the background of the above-mentioned prior art, and has as its object a novel and high quality which is excellent in coloring property, bulkiness and softness, has no spots, and has a smooth surface touch feeling. An object of the present invention is to provide a method capable of stably producing a complex false twisted yarn.
[0008]
[Means for Solving the Problems]
According to studies by the present inventors, the object of the present invention is to provide a titanium alkoxide represented by the following formula (I), a titanium alkoxide represented by the following general formula (I), and a titanium alkoxide represented by the following general formula (II). In the presence of at least one titanium compound selected from the group consisting of a reaction product of an aromatic polycarboxylic acid or an anhydride thereof and a phosphorus compound represented by the following general formula (III): A polyester obtained by polycondensation of an aromatic dicarboxylate ester and having a titanium and phosphorus content satisfying the following mathematical expressions (1) and (2) at the same time:
[0009]
Embedded image

[0010]
Embedded image

[0011]
Embedded image

[0012]
(Equation 2)

[0013]
The following (a) and (b) simultaneously obtained by blending two types of undrawn polyester multifilament yarns spun from a single spinneret or different spinnerets with a spinning draft difference of 10,000 to 100,000, simultaneously Using a false twisting machine in which the false twist heat set heater is a non-contact type, the simultaneous spinning and false twisting of the satisfying spun mixed yarn is performed under the conditions simultaneously satisfying the following (c) to (e). It has been found that this can be achieved by a method for producing a composite false twisted yarn.
(A) Birefringence index difference (Δn) between two types of undrawn polyester multifilament yarns: 0.02 ≦ Δn ≦ 0.05
(B) Elongation difference (ΔL) between two types of undrawn polyester multifilament yarn: 70% ≦ ΔL ≦ 200%
(C) False twist twisting tension (T ₁ ): 0.177 cN / dtex ≦ T ₁ ≦ 0.353 cN / dtex
(D) Number of false twists (K): 15000 / D ^1/2 times / m ≦ K ≦ 30000) / D ^1/2 times / m (where D is the fineness (dtex) of the composite false twisted yarn)
(E) False twist heater temperature (HA): 200 ° C ≦ HA ≦ 400 ° C
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail.
Examples of the catalyst for polycondensation of a polyester obtained by polycondensing an aromatic dicarboxylate ester used in the present invention include a titanium alkoxide represented by the above formula (I) and a titanium alkoxide represented by the above formula (I) At least one titanium compound selected from the group consisting of products obtained by reacting an alkoxide with the aromatic polycarboxylic acid represented by the formula (II) or an anhydride thereof is used.
[0015]
Specific examples of the titanium alkoxide include titanium tetrabutoxide, titanium tetraisopropoxide, titanium tetrapropoxide, titanium tetraalkoxide exemplified by titanium tetraethoxide, octaalkyltrititanate, and hexaalkyldititanate. Among them, titanium tetraalkoxide is preferable, and titanium tetrabutoxide is particularly preferable.
[0016]
The aromatic polycarboxylic acid represented by the general formula (II) or an anhydride thereof to be reacted with the titanium alkoxide includes phthalic acid, trimellitic acid, hemi-mellitic acid, pyromellitic acid and anhydrides thereof. It is preferably used.
[0017]
The conditions under which the titanium alkoxide is reacted with the aromatic polycarboxylic acid or its anhydride need not be particularly limited.For example, a part or all of the aromatic polycarboxylic acid or its anhydride is dissolved in an appropriate solvent. Then, a titanium alkoxide is dropped into this solution and heated at a temperature of 0 to 200 ° C. for at least 30 minutes, preferably at a temperature of 30 to 150 ° C. for 40 to 90 minutes. At this time, the reaction pressure is not particularly limited, and normal pressure is sufficient. As the solvent for dissolving the aromatic polycarboxylic acid or its anhydride, any solvent may be appropriately selected and used as needed, such as ethanol, ethylene glycol, trimethylene glycol, tetramethylene glycol, benzene, and xylene. Just fine.
[0018]
Here, the reaction molar ratio between the titanium alkoxide and the aromatic polycarboxylic acid or its anhydride does not need to be particularly limited, but is obtained when the proportion of the aromatic polycarboxylic acid or its anhydride becomes too small. If the effect of improving the color tone of the polyester becomes small, on the other hand, if it is too large, the polycondensation reaction may not easily proceed. For this reason, the reaction molar ratio between the titanium alkoxide and the aromatic polycarboxylic acid or its anhydride is preferably in the range of 2/1 to 2/5.
[0019]
The polyester in the present invention is obtained by polycondensing an aromatic dicarboxylate ester in the presence of the phosphorus compound represented by the above formula (III) in addition to the above titanium compound. Examples of the phosphorus compound (phosphonate compound) preferably used include carbomethoxymethanephosphonic acid, carbethoxymethanephosphonic acid, carbopropoxymethanephosphonic acid, carbbutoxymethanephosphonic acid, carbomethoxyphenylmethanephosphonic acid, and carbethoxyphenylmethanephosphonic acid. It is preferable to be selected from dimethyl esters, diethyl esters, dipropyl esters, dibutyl esters, and the like of phosphonic acid derivatives such as carboxypropenylphenylmethanephosphonic acid and carboxybutoxyphenylmethanephosphonic acid.
[0020]
Such a phosphonate compound, when compared with a phosphorus compound which is usually used as a stabilizer during a polycondensation reaction of a polyester, proceeds more slowly with the titanium compound, so that the catalytic activity of the titanium compound during the reaction is maintained. The time is prolonged, and as a result, the amount of the titanium compound can be reduced. Further, even if the phosphonate compound is used in a relatively large amount with respect to the titanium compound, the resulting polyester does not deteriorate in thermal stability and its color tone does not deteriorate.
[0021]
The polyester according to the present invention obtained by such polycondensation needs to have the titanium metal element concentration and the phosphorus element concentration simultaneously satisfying the following mathematical expressions (1) and (2).
[0022]
[Equation 3]

[0023]
Here, it is not preferable that (P / Ti) is less than 1, since coloring proceeds during polycondensation and the resulting polyester has a yellow hue. On the other hand, when (P / Ti) is more than 15, the polycondensation reactivity of the polyester is greatly reduced, so that it is difficult to obtain a target polyester.
[0024]
On the other hand, if (Ti + P) is less than 10, productivity in the spinning process is greatly reduced, and thus, fibers having satisfactory performance cannot be obtained. On the other hand, if (Ti + P) exceeds 100, a small amount of foreign matter due to the catalyst is generated during the polycondensation reaction, which is not preferable.
[0025]
In the formula (1), (P / Ti) is preferably in a range of 2 to 15, and particularly preferably in a range of 4 to 10. Further, (Ti + P) in the expression (2) is more preferably in the range of 20 to 70.
[0026]
The concentration of the Ti metal element is suitably in the range of 2 to 15 mmol% based on the total acid components of the polyester.
[0027]
The polyester used in the present invention is obtained by polycondensing an aromatic dicarboxylate ester in the presence of the above-mentioned titanium compound and phosphorus compound. The diester is preferably composed of an aliphatic dicarboxylic acid and an aliphatic glycol.
[0028]
Here, the aromatic dicarboxylic acid is preferably mainly terephthalic acid. More specifically, it is preferable that terephthalic acid accounts for 70 mol% or more, especially 80 mol% or more based on the total aromatic dicarboxylic acid. Here, preferred aromatic dicarboxylic acids other than terephthalic acid include, for example, phthalic acid, isophthalic acid, naphthalenedicarboxylic acid, diphenyldicarboxylic acid, diphenoxyethanedicarboxylic acid, and the like.
[0029]
The aliphatic glycol is preferably an alkylene glycol, and specific examples include ethylene glycol, trimethylene glycol, propylene glycol, tetramethylene glycol, neopentyl glycol, hexane methylene glycol, dodecamethylene glycol and the like. Among them, ethylene glycol is preferred.
[0030]
Among them, polyesters in which 70 mol% or more of all repeating units are composed of ethylene terephthalate are preferred, and polyethylene terephthalate is particularly preferred.
[0031]
The polyester according to the present invention may be a copolymerized polyester obtained by copolymerizing at least one acid component or diol component other than the aromatic dicarboxylic acid and the aliphatic glycol.
[0032]
As a preferably used copolymerization component, as an acid component, adipic acid, sebacic acid, azelaic acid, aliphatic dicarboxylic acids such as decanedicarboxylic acid, and difunctional carboxylic acids such as alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid. I can give it. Examples of the diol component include alicyclic glycols such as cyclohexanedimethanol, and aromatic diols such as bisphenol, hydroquinone, and 2,2-bis (4-β-hydroxyethoxyphenyl) propane.
[0033]
Further, polyfunctional compounds such as trimesic acid, trimethylolethane, trimethylolpropane, trimethylolmethane, and pentaerythritol may be copolymerized in a small amount within a range in which the obtained polyester is substantially linear.
[0034]
In the present invention, an aromatic dicarboxylate ester comprising the above aromatic dicarboxylic acid and an aliphatic glycol is used, and the aromatic dicarboxylate ester is obtained by diesterification of an aromatic dicarboxylic acid and an aliphatic glycol. It may be obtained by a reaction, or may be obtained by a transesterification reaction between a dialkyl ester of an aromatic dicarboxylic acid and an aliphatic glycol, and its production method is arbitrary. However, the latter method based on a transesterification reaction is more preferable than the former method based on a diesterification reaction because scattering of the phosphorus compound present during the polycondensation reaction is smaller.
[0035]
It is preferable that a part and / or the whole amount of the titanium compound is added before the start of the transesterification reaction, so that the titanium compound is also used as a catalyst for both the transesterification catalyst and the polycondensation reaction catalyst. By doing so, the content of the metal catalyst in the obtained polyester can be reduced.
[0036]
Hereinafter, preferred embodiments will be described more specifically with reference to polyethylene terephthalate as an example. First, a transesterification reaction between a dialkyl ester of terephthalic acid and ethylene glycol is carried out by a titanium alkoxide represented by the general formula (I) and an aromatic polyvalent compound represented by the titanium alkoxide and the general formula (II). The reaction is performed in the presence of at least one titanium compound selected from the group consisting of a product obtained by reacting a carboxylic acid or an anhydride thereof. A phosphorus compound represented by the above general formula (III) is further added to the obtained reaction mixture containing a diester of terephthalic acid and ethylene glycol, and polycondensation is performed in the presence of the phosphorus compound.
[0037]
The transesterification reaction is usually carried out under normal pressure, but when carried out under a pressure of 0.05 to 0.20 MPa, the reaction by the catalytic action of the titanium compound is further promoted, and the by-product of diethylene glycol is reduced. Therefore, the properties of the obtained polyester, such as thermal stability, are improved, which is preferable. The temperature is suitably in the range of 160 to 260 ° C.
[0038]
Next, in the presence of the titanium compound and the phosphorus compound, the ethylene glycol ester or a low polymer thereof obtained above is heated under reduced pressure to a temperature not lower than the melting point of the obtained polyester and lower than the decomposition point (usually 240 ° C to 240 ° C). (280 ° C.) for polycondensation. In the polycondensation reaction, it is desirable to carry out the reaction while distilling unreacted ethylene glycol and ethylene glycol generated by the polycondensation out of the reaction system.
[0039]
The polycondensation reaction may be performed in one tank or may be performed in a plurality of tanks. For example, when the polycondensation reaction is performed in two stages, the polycondensation reaction in the first tank has a reaction temperature of 245 to 290 ° C, preferably 260 to 280 ° C, and a pressure of 100 to 1 kPa, and preferably 50 to 1 kPa. The polycondensation reaction in the final second tank is performed at a reaction temperature of 265 to 300 ° C, preferably 270 to 290 ° C, and a reaction pressure of usually 10 to 1000 Pa, preferably 30 to 500 Pa. Done below.
[0040]
The polyester used in the present invention can be produced as described above, and the obtained polyester is usually made into a granular form (chip form). In addition, it is desirable that the intrinsic viscosity of the obtained polyester is 0.40 to 0.80, preferably 0.50 to 0.70. If desired, the intrinsic viscosity may be further increased by solid-phase polycondensation.
[0041]
The granular polyester supplied to the solid-phase polycondensation step is subjected to preliminary crystallization by heating to a temperature lower than the temperature at which the solid-phase polycondensation is performed, and then to the solid-phase polycondensation step. Good.
[0042]
The polyester according to the present invention thus obtained may contain a small amount of additives as necessary, for example, a lubricant, a pigment, a dye, an antioxidant, a solid phase polymerization accelerator, a fluorescent brightener, an antistatic agent, and an antibacterial agent. , An ultraviolet absorber, a light stabilizer, a heat stabilizer, a light-shielding agent, a matting agent, and the like. Among them, titanium oxide as a matting agent and an antioxidant as a stabilizer are preferably added, and usually, titanium oxide having an average particle size of 0.01 to 2 μm is added to the finally obtained polyester composition. It is added so that the occupying ratio is 0.01 to 10% by weight.
[0043]
As the antioxidant, a hindered phenol-based antioxidant is preferably added. The addition amount of the hindered phenolic antioxidant is usually 1% by weight or less. If it exceeds 1% by weight, it may not only cause scum at the time of spinning, but even if it exceeds 1% by weight, the effect of improving the melt stability will be saturated. The addition amount of such an antioxidant is particularly preferably in the range of 0.005 to 0.5% by weight. It is more preferable to use a thioether-based secondary antioxidant in addition to the hindered phenol-based antioxidant.
[0044]
The method of adding these antioxidants to the polyester is not particularly limited, but it is preferably added at any stage after the end of the transesterification reaction or esterification reaction and before the completion of the polymerization reaction.
[0045]
In the present invention, the above polyester is simultaneously spun using a single or different spinneret with a spinning draft difference in the range of 10,000 to 100,000, and simultaneously satisfies the following (A) and (B). It is necessary to obtain an undrawn polyester multifilament yarn having a different orientation difference, and to subject the spun mixed fiber obtained by mixing and preferably mixing and entanglement the yarn to simultaneous drawing and false twisting.
(A) Birefringence difference (Δn) between two types of undrawn polyester multifilament yarns: 0.02 ≦ Δn ≦ 0.05, preferably 0.025 ≦ Δn ≦ 0.045
(B) Elongation difference (ΔL) between two types of undrawn polyester multifilament yarn: 70% ≦ ΔL ≦ 200%, preferably 90% ≦ ΔL ≦ 180%
[0046]
Here, when the spinning draft difference is less than 10,000, the false twisted crimped yarn obtained by reducing the elongation difference (ΔL) between the undrawn multifilament yarns tends to be loose, resulting in insufficient bulk. As a result, the desired texture of the processed yarn cannot be obtained. On the other hand, if the spinning draft difference exceeds 100,000, not only the spinnability of the high spinning draft component deteriorates, but also the number of breaks and fluffs during false twisting increases, which is not preferable.
[0047]
It is important to further adjust and set the spinning draft difference between the two types of undrawn polyester multifilament yarns having the above-mentioned spinning draft difference so that the elongation difference (ΔL) is within the above range. If the difference is less than 70%, the bulkiness of the obtained processed yarn will be insufficient, while if it exceeds 200%, undesired spots tend to occur, which is not preferable.
[0048]
It is important that the birefringence difference (Δn) of the two types of undrawn polyester multifilament yarns be within the above range in order to optimize the twisting tension during false twisting and prevent surging. If the birefringence difference is less than 0.02, spots become large due to heat setting spots due to the occurrence of surging. On the other hand, if it exceeds 0.05, the fiber cross-sectional shape becomes non-uniform, thread breakage, fluff, etc. increase, which is not preferable.
[0049]
In addition, the total fineness ratio of these undrawn polyester multifilament yarns is preferably 5: 5 to 3: 7 (core portion: sheath portion), and it is preferable that there are many portions that become the sheath portion. The total fineness is the fineness after false twisting. A range of 75 to 330 dtex is preferred. In addition, it is preferable that each single yarn fineness is such that, after false twisting, the high draft side which becomes the core yarn becomes 30 to 130 dtex and the low draft side which becomes the sheath yarn becomes 40 to 200 dtex.
[0050]
The undrawn yarn having such a draft difference melts and discharges polyester from two different discharge hole groups in which the hole diameter difference is set to an appropriate value, and discharges the polyester at, for example, 800 to 4000 m / min, preferably 1000 to 2000 m / min. Min, particularly preferably 1000 to 1500 m / min.
[0051]
The mixing process of the undrawn yarn may be performed at a stage before the take-up roller or at a stage after passing through the take-up roller. The fiber mixing method is not particularly limited, and a conventionally known method may be appropriately selected. For example, a method in which the fibers are mixed and entangled by air pressure treatment using an interlace nozzle is preferable. If the number of entanglements is too large, the number of fluffs tends to increase, while if too small, entanglement tends to occur due to poor fiber mixing. Therefore, the range of 10 to 70 pieces / m is appropriate.
[0052]
In the present invention, a spun mixed fiber that satisfies the above requirements is drawn using a false twisting machine in which a false twist heat set heater is a non-contact type, so that the following (c) to (e) are simultaneously satisfied. It is necessary to set the false twist processing conditions such as the magnification and to perform the simultaneous simultaneous false twist processing.
(C) False twist twist tension (T ₁ ): 0.177 cN / dtex ≦ T ₁ ≦ 0.353 cN / dtex, preferably 0.221 cN / dtex ≦ T ₁ ≦ 0.309 cN / dtex
(D) Number of false twists (K): 15000 / D ^1/2 times / m ≦ K ≦ 30000) / D ^1/2 times / m (where D is the fineness (dtex) of the composite false twisted yarn), preferably Is 20000 / D ^1/2 times / m ≦ K ≦ 25000) / D ^1/2 times / m
(E) False twist heater temperature (HA): 200 ° C ≦ HA ≦ 400 ° C, 250 ° C ≦ HA ≦ 350 ° C
Here, if the twisting tension is less than the above range, surging is likely to occur and dye spots increase, which is not preferable.On the other hand, if the twisting tension exceeds the range, the generation of fluff increases and the breakage increases. It is not preferable because yarns are easily generated. In addition, if the untwisting tension is too low, it is easy to cause spot defects (spot untwisted shape), while if it is too high, fluff is likely to occur frequently, so the untwisting tension should be in the range of 0.088 to 0.265 cN / dtex. desirable.
[0053]
Next, when the number of false twists (twist / m) is less than 15000 / D ^1/2 turn / m, the hand is hard and flat yarn-like, which is not preferable. On the other hand, 30,000 / D ^1/2 turn / M is not preferable because thread breakage and fluff are likely to occur rapidly.
[0054]
When the false twist heater temperature (HA (HA: heat set heater temperature) is less than 200 ° C., unevenness in the yarn longitudinal direction of the yarn arranged in the sheath of the obtained composite processed yarn (due to insufficient heat setting). (Stains) tend to occur, and the bulkiness is insufficient, so that the object of the present invention cannot be achieved. Inability to achieve purpose.
[0055]
In the case where re-heat treatment is performed after false twisting, the overfeed ratio of the yarn is preferably in the range of 0 to 8%, and if it is less than 0% (that is, elongation), the bulky property of the obtained composite false twisted yarn tends to decrease. On the other hand, if it exceeds 8%, the loop of the obtained composite false twisted yarn tends to be large and the quality tends to deteriorate.
[0056]
Next, FIG. 1 is a schematic process diagram showing one embodiment of the manufacturing method of the present invention. In FIG. 1, two types of undrawn polyester multifilament yarns having a draft difference, which have been subjected to a spinning and entanglement process in advance, are supplied to a drawing simultaneous false twisting region by a feed roller 3 via a guide 2. Next, the sheet is twisted and untwisted by the friction disk 7 while being stretched between the feed roller 3 and the first delivery roller 8, and is thermally fixed by the first false twist heat set heater 5. The false-twisted yarn is re-heat-treated by the re-heat treatment heater 9 between the first delivery roller 8 and the second delivery roller 10 as necessary, and then wound up as a package 12 by the take-up roller 11. Can be
[0057]
[Action]
In the method for producing a composite false twisted yarn of the present invention described in detail above, a polyester obtained by polycondensation in the presence of a specific titanium compound and a phosphorus compound is used and melt-spun by giving a spinning draft difference. New and high quality composite with excellent color developability, bulkiness and softness, no burrs and a smooth surface touch due to the use of spun mixed yarn consisting of various undrawn yarns. False twisted yarn can be continuously and stably produced over a long period of time.
[0058]
【Example】
Hereinafter, the present invention will be described more specifically with reference to examples. The measurement of each characteristic value in Examples and Comparative Examples was performed by the following method.
[0059]
(1) Titanium metal element content and phosphorus element content After a granular polyester sample was heated and melted on an aluminum plate, a test molded body having a flat surface was prepared with a compression press, and a fluorescent X made by Rigaku Denki Kogyo Co., Ltd. The titanium metal element content and the phosphorus element content were measured using a line measuring device 3270E.
[0060]
However, regarding the titanium atom concentration in the polymer to which titanium oxide was added as a matting agent, the sample was dissolved in hexafluoroisopropanol, the titanium oxide particles were precipitated from the solution by a centrifugal separator, and only the supernatant liquid was decanted. The test sample was prepared by collecting and evaporating the solvent, and the sample was measured.
[0061]
(2) Intrinsic viscosity Orthochlorophenol was used as a solvent and measured at a temperature of 35 ° C. according to a conventional method.
[0062]
(3) Birefringence The birefringence was determined from the retardation of polarized light observed on the fiber surface using an optical microscope and a compensator according to a conventional method.
[0063]
(4) Foreign matter height of the spinneret Melt spinning is performed under the method and conditions shown in each example, and after 3, 6, and 9 days, a releasing agent is sprayed on the surface of the spinneret to prevent the discharged polymer from adhering. After removal, the height of the cap foreign matter adhered and deposited around the discharge hole was measured with a microscope. The height of the cap foreign matter was measured for all the ejection holes, and the height was represented by an average value thereof.
[0064]
(5) Spinning breakage rate The number of spinning breaks generated during the operation of the spinning machine was recorded except for the breakage caused by artificial or mechanical factors, and the spinning breakage rate (%) was calculated by the following formula.
Spinning breakage rate (%) = [number of breaks / (number of operating winders × number of doffs)] × 100
Here, the doff number refers to the number of times the undrawn yarn package is wound up to a predetermined amount (10 kg).
[0065]
(6) Number of Fluffs Using a DT-104 fluff counter manufactured by Toray Industries, Inc., the stretched false twisted yarn is continuously measured at a speed of 500 m / min for 20 minutes to determine the number of fluffs generated (pieces / 10 ⁴ m). Counted.
[0066]
(7) Stretched false twist rate Except for broken threads caused by artificial or mechanical factors, the number of times of thread breakage generated during the operation of the stretch false twisting machine is recorded, and the stretched false twist rate (%) is calculated by the following formula. Was calculated.
Drawing false twist ratio (%) = [number of yarn breaks / (number of operating weights × number of doffs)] × 100
Here, the doff number refers to the number of times the false twisted yarn package is wound up to a predetermined amount (2.5 kg).
[0067]
(8) (L ^* -b ^* ) value Using a 12 gauge circular knitting machine, the polyester fiber was knitted into a tube having a length of 30 cm, and the L ^* value and the b ^* value were measured using a hunter type color difference meter CR-200 manufactured by Minolta Co., Ltd. It measured, and made the difference into (L ^* -b ^* ) value.
[0068]
(9) Strength / elongation Measured in accordance with JIS-L1013.
[0069]
(10) <Spinning draft>
The ratio (S / T) between the take-up speed (S) and the linear discharge speed (T) of the polymer was calculated.
[0070]
(11) Elongation at break of undrawn polyester multifilament It was measured according to JIS L-1013-75.
[0071]
(12) Crimp rate (TC)
A tension of 0.044 cN / dtex is applied to the composite false twisted yarn and wound around a skewer frame to make a skein of about 3300 dtex. After creating the cassette, a load of 0.00177 cN / dtex + 0.177 cN / dtex is applied to one end of the cassette, and the length L ₀ (cm) after one minute has elapsed is measured. Next, in a state where the load of 0.177 cN / dtex is removed, a treatment is performed in boiling water at 100 ° C. for 20 minutes. After the boiling water treatment, the load of 0.00177 cN / dtex is removed, and the mixture is naturally dried in a free state for 24 hours. A load of 0.00177 cN / dtex + 0.177 cN / dtex is again applied to the naturally dried sample, and the length L ₁ (cm) after one minute has elapsed is measured. Then removed load of 0.177cN / dtex, after a lapse of 1 minute length _{L 2} was measured to calculate the shrinkage wound in the following formula. This measurement was performed 10 times, and the result was represented by the average value.
TC (%) = [(L ₁ −L ₂ ) / L ₀ ] × 100
[0072]
(13) Hand of composite false twisted yarn The obtained composite false twisted yarn is knitted by a tubular knitting machine, and the texture (soft feeling) of the knitted fabric after scouring, dyeing, and final setting according to a conventional method. The sensory evaluation was performed by five skilled persons based on the total and the surface touch. The judgment was made in three stages of 1 (poor) x to 3 (very good), and 2 or more was regarded as a pass level.
[0073]
(14) The bulky composite false twisted yarn is taken 320 turns on a skein (perimeter: 1.25 m), a load of 5.88 cN (6.0 g) is hung on one end of the sample that has been folded in half, and dried at 180 ° C. After cooling, a volume (Vcm ³ ) having a constant weight (Wg) after cooling was measured under a load of 6.4 g, and calculated by the following equation.
Bulkiness (cm ³ / g) = V / W
[0074]
(15) Boiling water shrinkage (BWS)
A skein of a composite false twisted yarn of about 3300 dtex is made, a load of 0.0883 cN / dtex is applied thereto, the original length L ₀ (cm) is measured, and then the load of the skein is changed to 0.00177 cN / dtex. This was heat-treated in boiling water for 30 minutes, and then dried at room temperature. The load was changed to 0.0883 cN / dtex, the length L ₁ (cm) was measured, calculated by the following formula, and measured 10 times. Then, the average value was obtained.
Boiling water shrinkage (BWS) = (L ₀ −L ₁ ) / L ₀ × 100
[0075]
[Examples 1 to 3, Comparative Example 1]
Using titanium trimellitate and triethyl phosphonoacetate in such amounts that the amounts of titanium metal element (Ti) and phosphorus element concentration (P) contained in the polyester are as shown in Table 1, dimethyl terephthalate and ethylene are used. Glycol was polycondensed to give polyethylene terephthalate having an intrinsic viscosity of 0.630.
[0076]
After the obtained polyethylene terephthalate pellets were dried at 150 ° C. for 5 hours, they were melted in a melt spinning equipment equipped with a screw type extruder, introduced into a spin block at 295 ° C., and the draft difference from the spinneret was 77,000. While discharging and cooling and solidifying the polymer stream with the air stream ejected from the cross-flow type air blower, the metering nozzle type oiling device installed 80 cm below the spinneret converges while refueling. After being subjected to the confounding treatment, it is taken out at a speed of 1300 m / min, and 300dtex / 72fil (high spinning draft component: 120dtex / 24fil, low spinning draft component: 180d / 48fil, birefringence difference 0.025, cutting elongation difference 150) %, The number of entanglements: 25 / m), and 10 kg was wound into a package. The above melt spinning operation was performed continuously for 9 days.
[0077]
Next, the obtained polyester unstretched mixed fiber yarn package was subjected to simultaneous drawing and false twisting using the apparatus shown in FIG. That is, using a HTS-1500 type draw false twisting machine manufactured by Teijin Seiki Co., Ltd. equipped with a urethane disk having a diameter of 58 mm as a false twist tool, a draw ratio of 1.80, a false twist heater temperature of 300 ° C., and a draw false twist speed of 700 m A draw false twisting process was performed under stretch false twisting conditions of / min to obtain a composite false twisted yarn of 170 dtex / 72 fill. In addition, drawing false twisting was performed by a method of forming four 2.5 kg wound false twisted yarn packages from a 10 kg wound undrawn package.
[0078]
The twisting tension (T ₁ ) at that time was 49 cN (0.256 cN / dtex), the untwisting tension (T ₂ ) was 37.2 cN, and processing was performed at a speed of 700 m / min. The resulting composite false twisted yarn had a bulkiness of 36 cm ³ / g, which was extremely large.
[0079]
The knitted fabric obtained by knitting the obtained composite false-twisted yarn into a tubular knit, dyeing and finishing it according to a conventional method exhibited a smooth, smooth surface touch and a soft feel. Further, this false twisted yarn is twisted at 1800 T / m, woven into a twill structure having a warp density of 176 yarns / 3.79 cm and a weft density of 106 yarns / 3.79 cm, and relaxed according to a conventional method (at a temperature of 120 ° C.). , 20 minutes), presetting (temperature 180 ° C, 45 seconds), alkali weight reduction treatment (weight loss 17%), dyeing processing (temperature 130 ° C, 45 minutes), and final setting (temperature 160 ° C, 45 seconds) To obtain a woven fabric. The obtained woven fabric was an excellent woven fabric exhibiting a smooth surface touch and excellent drapability. Table 1 summarizes the obtained results.
[0080]
[Comparative Example 2]
The same procedure as in Example 1 was carried out except that ethylene glycol diester of terephthalic acid was polycondensed using antimony trioxide (Sb ₂ O ₃ ) as a catalyst to obtain polyethylene terephthalate having an intrinsic viscosity of 0.630. Table 1 shows the results.
[0081]
In addition, in this comparative example, as shown in Table 1, as the spinning time elapses, foreign matter in the die rapidly grows as the spinning time elapses, and as the bending, the spike, and the turning of the discharged yarn increase, the spun yarn breaks sharply. The increase was observed, and after 3 days from the spinning, spinning was frequently caused and normal spinning operation became difficult, so the operation was stopped.
[0082]
[Table 1]

[0083]
[Comparative Example 3]
The polyethylene terephthalate obtained in Example 1 was spun at a spinning draft of 156 and a spinning speed of 1300 m / min to obtain a low-oriented undrawn polyester multifilament having an elongation of 360%, a birefringence of 0.015, and 167 dtex / 48 filaments. . Separately, spinning was performed at a spinning draft of 188 at a spinning speed of 3200 m / min to obtain highly oriented undrawn polyester filaments having an elongation of 125% and a birefringence of 0.045 and 138 dtex / 24 filaments.
[0084]
After both filaments are aligned and mixed and entangled (50 entanglements / m), a triaxial friction disk is used as a false twisting tool at a draw ratio of 1.63 and a false twist temperature of 200 ° C., and twisting tension ( _{T 1) 73.5cN (0.389cN / dtex} ), and processed at 400 meters / min as untwisting tension _(T 2) _49cN, to give a composite false twisted yarn of 188dtex / 72fil. The bulkiness of the obtained false twisted yarn was as low as 19 cm ³ / g.
[0085]
When the composite false twisted yarn was processed into a woven fabric in the same manner as in Example 1, the obtained woven fabric had a rough surface touch and a poor feel.
[0086]
[Examples 4 to 14, Comparative Examples 4 to 11]
A composite false twisted yarn was obtained in the same manner as in Example 1, except that the difference in spinning draft, difference in birefringence, and difference in elongation were changed as shown in Table 2. Table 2 summarizes the results. Comparative Example 3 is also shown.
[0087]
Further, a composite false twisted yarn was obtained in the same manner as in Example 1 except that the false twisting conditions were changed as described in Table 3 or 4. These results are shown in Tables 3 and 4, respectively.
[0088]
[Table 2]

[0089]
[Table 3]

[0090]
[Table 4]

[0091]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to this invention, it is excellent in coloring property, a feeling of bulkiness, and a soft feeling. Moreover, it is hard to generate | occur | produce the coloring spots, such as a crepe spot, and also has a double-layered composite false twisting thread which has a smooth surface touch feeling. Can be obtained for a stable period.
[Brief description of the drawings]
FIG. 1 is a schematic view of an apparatus for producing a composite false twisting yarn used in Example 1.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Polyester fiber 2 Guide 3 Feed roller 4 Interlace nozzle 5 Heat set heater (false twist temperature)
6 cooling plate 7 twisting device (false twist disk)
8 First delivery roller 9 Heat treatment heater (heat treatment temperature)
10 Second delivery roller 11 Winding roller 12 Package

Claims (4)

A titanium alkoxide represented by the following formula (I) and a titanium alkoxide represented by the following general formula (I) were reacted with an aromatic polycarboxylic acid represented by the following general formula (II) or an anhydride thereof. Titanium and phosphorus obtained by polycondensing an aromatic dicarboxylate ester in the presence of at least one titanium compound selected from the group consisting of products and a phosphorus compound represented by the following general formula (III): The polyester whose content concentration simultaneously satisfies the following mathematical formulas (1) and (2):

The following (a) and (b) simultaneously obtained by blending two types of undrawn polyester multifilament yarns spun from a single spinneret or different spinnerets with a spinning draft difference of 10,000 to 100,000, simultaneously Using a false twisting machine in which the false twist heat set heater is a non-contact type, the simultaneous spinning and false twisting of the satisfying spun mixed yarn is performed under the conditions simultaneously satisfying the following (c) to (e). A method for producing a composite false twisted yarn.
(A) Birefringence index difference (Δn) between two types of undrawn polyester multifilament yarns: 0.02 ≦ Δn ≦ 0.05
(B) Elongation difference (ΔL) between two types of undrawn polyester multifilament yarn: 70% ≦ ΔL ≦ 200%
(C) False twist twisting tension (T ₁ ): 0.177 cN / dtex ≦ T ₁ ≦ 0.353 cN / dtex
(D) Number of false twists (K): 15000 / D ^1/2 times / m ≦ K ≦ 30000) / D ^1/2 times / m (where D is the fineness (dtex) of the composite false twisted yarn)
(E) False twist heater temperature (HA): 200 ° C ≦ HA ≦ 400 ° C The aromatic dicarboxylate ester is a titanium alkoxide represented by the following formula (I), a titanium alkoxide represented by the following general formula (I) and an aromatic polycarboxylic acid represented by the following general formula (II) or A diester obtained by a transesterification reaction between an aromatic dicarboxylic acid dialkyl ester and an aliphatic glycol in the presence of at least one titanium compound selected from the group consisting of products obtained by reacting the anhydride with the anhydride. Item 7. A method for producing a composite false twisted yarn according to Item 1.

3. The method according to claim 1, wherein the polyester is polyethylene terephthalate. The method for producing a composite false twisted yarn according to any one of claims 1 to 3, wherein the spinning speed of the mixed fiber is 1000 to 1500 m / min.

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