JP2004238553A - Polyester for atmospheric pressure dyeing and fiber - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polyester for atmospheric pressure dyeing which has an excellent color tone, is minimized in increase in a pack pressure and generation of a deposit on a spinneret even when subjected to continuous long-term spinning exhibits excellent molding properties and high productivity and is improved in hue, and a fiber. <P>SOLUTION: The polyester is obtained by copolymerizing a specific dicarboxylic acid component, a specific glycol component and a specific polyoxyalkylene glycol component using a specific titanium/phosphorus unreacted mixture as a polymerization catalyst. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

【００２６】
【化４】

【００２７】
【化５】

【００２８】
【化６】

【００２９】
【数４】

【００３０】
【発明の実施の形態】
以下、本発明について詳細に説明する。
本発明の常圧染色用ポリエステルは、炭素数２〜２０の飽和脂肪族鎖及び／又は飽和脂環族鎖を有するジカルボン酸成分（Ａ）と炭素数３〜１５の飽和脂肪族鎖及び／又は飽和脂環族鎖を有するグリコール成分（Ｂ）と炭素数２０〜４０の飽和脂肪族鎖及び／又は飽和脂環族鎖を有するジカルボン酸成分（Ｃ）と分子量２００〜６０００のポリオキシアルキレングリコール成分（Ｄ）の各々の共重合量が下記数式（１）〜（５）を同時に満足する必要がある。
【００３１】
【数５】

【００３２】
ここで、上記式Ａで表される炭素数２〜２０の飽和脂肪族鎖及び／又は飽和脂環族鎖を有するジカルボン酸成分（Ａ）としては、具体的にはシュウ酸、マロン酸、コハク酸、アジピン酸、ピメリン酸、スベリン酸、アゼライン酸、セバシン酸等が例示されるが、特にセバシン酸が好ましく使用される。
【００３３】
上記式Ｂで表される炭素数３〜２０の飽和脂肪族鎖及び／又は飽和脂環族鎖を有するグリコール成分（Ｂ）としては、トリメチレングリコール、テトラメチレングリコール、ペンタメチレングリコール、ヘキサメチレングリコール、ヘプタメチレングリコール、オクタメチレングリコール、ノナメチレングリコール、デカメチレングリコール、シクロヘキサンジメタノール、ネオペンチレングリコール等が例示されるが、特にヘキサメチレングリコールが好ましく使用される。
【００３４】
上記式Ｃで表される炭素数２０〜４０の飽和脂肪族鎖及び／又は飽和脂環族鎖を有するジカルボン酸成分（Ｃ）としては、具体的にはダイマー酸等が例示されるが、ダイマー酸としてはリノール酸やオレイン酸を出発原料として製造されたダイマー酸が好ましく使用される。
【００３５】
上記式Ｄで表される分子量２００〜６０００のポリオキシアルキレングリコール成分（Ｄ）としてはポリエチレングリコール、ポリプロピレングリコール、ポリテトラメチレングリコール等が例示されるが、特に分子量４００〜４０００のポリエチレングリコール、分子量４００〜２０００のポリテトラメチレングリコールが好ましく使用される。
【００３６】
上記式Ａ、Ｂで表されるジカルボン酸成分（Ａ）、グリコール成分（Ｂ）の共重合量はそれぞれ２０モル％以下である必要がある。該共重合量が２０モル％を超えると得られるポリエステル繊維の強度や耐熱性が低下し好ましくない。該共重合量はそれぞれ１７モル％以下の範囲が好ましく、１５モル％の範囲が更に好ましい。また、上記式Ｃで表されるジカルボン酸成分（Ｃ）の共重合量は２０重量％以下である必要がある。該共重合量が２０重量％を超えると得られるポリエステル繊維の強度や耐熱性が低下する為好ましくない。該共重合量は１７重量％以下の範囲が好ましく、１５重量％の範囲が更に好ましい。更に上記式Ｄで表されるポリオキシアルキレングリコール成分（Ｄ）の共重合量は１５重量％以下である必要がある。該共重合量が１５重量％を超えると得られるポリエステル繊維の強度や耐熱性、耐光性が低下する為好ましくない。該共重合量は１２重量％以下の範囲が好ましく、１０重量％の範囲が更に好ましい。
【００３７】
上記式Ａ、Ｂ、Ｃ、Ｄの共重合量の合計は５％〜２０％の範囲にある必要がある。該共重合量の合計量が５％未満の場合、最終的に得られる繊維の常圧染色性が不十分となり、また、２０％を超える場合は得られるポリエステル繊維の強度や耐熱性、耐光性が低下する為好ましくない。該共重合量は６〜１７％の範囲が好ましく、７〜１５％の範囲が更に好ましい。
【００３８】
本発明の常圧染色用ポリエステルはその特性を損なわない範囲、好ましくは５モル％以下の範囲でテレフタル酸成分、エチレングリコール成分、炭素数２〜２０の飽和脂肪族鎖及び／又は飽和脂環族鎖を有するジカルボン酸成分（Ａ）と炭素数３〜２０の飽和脂肪族鎖及び／又は飽和脂環族鎖を有するグリコール成分（Ｂ）と炭素数２０〜４０の飽和脂肪族鎖及び／又は飽和脂環族鎖を有するジカルボン酸成分（Ｃ）、分子量２００〜６０００のポリオキシアルキレングリコール成分（Ｄ）以外の成分を共重合していても良く、例えばナフタレンジカルボン酸、オルトフタル酸、ジフェニルジカルボン酸、ジフェニルエーテルジカルボン酸、ジフェニルスルホンジカルボン酸、ベンゾフェノンジカルボン酸、フェニルインダンジカルボン酸、５−スルホキシイソフタル酸金属塩、５−スルホキシイソフタル酸ホスホニウム塩等の芳香族ジカルボン酸成分、ｏ−キシリレングリコール、ｍ−キシリレングリコール、ｐ−キシリレングリコール、１，４−ビス（２−ヒドロキシエトキシ）ベンゼン、１，４−ビス（２−ヒドロキシエトキシエトキシ）ベンゼン、４，４’−ビス（２−ヒドロキシエトキシ）ビフェニル、４，４’−ビス（２−ヒドロキシエトキシエトキシ）ビフェニル、２，２−ビス［４−（２−ヒドロキシエトキシ）フェニル］プロパン、２，２−ビス［４−（２−ヒドロキシエトキシエトキシ）フェニル］プロパン、１，３−ビス（２−ヒドロキシエトキシ）ベンゼン、１，３−ビス（２−ヒドロキシエトキシエトキシ）ベンゼン、１，２−ビス（２−ヒドロキシエトキシ）ベンゼン、１，２−ビス（２−ヒドロキシエトキシエトキシ）ベンゼン、４，４’−ビス（２−ヒドロキシエトキシ）ジフェニルスルホン、４，４’−ビス（２−ヒドロキシエトキシエトキシ）ジフェニルスルホン等の芳香族グリコール成分、ヒドロキノン、２，２−ビス（４−ヒドロキシフェニル）プロパン、レゾルシン、カテコール、ジヒドロキシナフタレン、ジヒドロキシビフェニル、ジヒドロキシジフェニルスルホン等のジフェノール類等が挙げられる。これらは１種を単独で用いても２種以上を併用してもどちらでも良い。
【００３９】
本発明の常圧染色用ポリエステルは、下記一般式（Ｉ）で表されるチタン化合物、及び下記一般式（Ｉ）で表されるチタン化合物と下記一般式（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一種を含むチタン化合物成分と、下記一般式（ＩＩＩ）により表されるリン化合物との未反応混合物から実質的になる触媒系を下記数式（６）及び（７）を同時に満足するように用いて重合されている必要がある。
【００４０】
【化７】

【００４１】
【化８】

【００４２】
【化９】

【００４３】
【数６】

【００４４】
本発明の製造方法において、重合反応に触媒として用いられるチタン化合物成分は、触媒に起因する異物を低減する観点から、ポリマー中に可溶なチタン化合物を使用することが必要であり、該チタン化合物成分としては、下記一般式（Ｉ）で表される化合物、若しくは一般式（ＩＩ）で表される化合物と下記一般式（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である必要がある。
【００４５】
【化１０】

【００４６】
【化１１】

【００４７】
ここで、一般式（Ｉ）で表されるチタン化合物としては、具体的にはテトライソプロポキシチタン、テトラプロポキシチタン、テトラ−ｎ−ブトキシチタン、テトラエトキシチタン、テトラフェノキシチタン、オクタアルキルトリチタネート、及びヘキサアルキルジチタネートなどが好ましく用いられる。
【００４８】
また、本発明の製造方法において、該チタン化合物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。
【００４９】
上記チタン化合物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場合には、溶媒に芳香族多価カルボン酸又はその無水物の一部または全部を溶解し、この混合液にチタン化合物を滴下し、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分間加熱することによって行われる。この際の反応圧力については特に制限はなく、常圧で十分である。なお、芳香族多価カルボン酸また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、ベンゼン及びキシレン等から所望に応じていずれを用いることもできる。
【００５０】
ここで、チタン化合物と芳香族多価カルボン酸またはその無水物との反応モル比には特に限定はないが、チタン化合物の割合が高すぎると、得られるポリエステルの色調が悪化したり、軟化点が低下したりすることがあり、逆にチタン化合物の割合が低すぎると重合反応が進みにくくなることがある。このため、チタン化合物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。
【００５１】
本発明の製造方法に重合触媒として用いる触媒系は、上記のチタン化合物成分は、下記一般式（ＩＩＩ）により表されるリン化合物との未反応混合物から実質的になるものである。
【００５２】
【化１２】

【００５３】
上記一般式（ＩＩＩ）のリン化合物（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、カルボプトキシメタンホスホン酸、カルボメトキシ−ホスホノ−フェニル酢酸、カルボエトキシ−ホスホノ−フェニル酢酸、カルボプロトキシ−ホスホノ−フェニル酢酸およびカルボブトキシ−ホスホノ−フェニル酢酸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およびジブチルエステル類から選ばれることが好ましい。
【００５４】
上記のホスホネート化合物は、通常安定剤として使用されるリン化合物に比較して、チタン化合物との反応が比較的緩やかに進行するので、反応中における、チタン化合物の触媒活性持続時間が長く、結果として該チタン化合物のポリエステルへの添加量を少なくすることができる。また、一般式（ＩＩＩ）のリン化合物を含む触媒系に多量に安定剤を添加しても、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、その色調を不良化することが無い。
【００５５】
また、上記の触媒系は下記数式（６）及び（７）を同時に満足するものである必要がある。
【００５６】
【数７】

【００５７】
ここで、（Ｐ／Ｔｉ）が０．６５未満の場合、ポリエステルの色相が黄味を帯びたものであり、好ましくない。また、（Ｐ／Ｔｉ）が５を越えるとポリエステルの重合反応性が大幅に低下し、目的とするポリエステルを得ることが困難となる。この（Ｐ／Ｔｉ）の適正範囲は通常の金属触媒系よりも狭いことが特徴的であるが、適正範囲にある場合、本発明のような従来にない効果を得ることができる。
【００５８】
一方、（Ｔｉ＋Ｐ）が１０に満たない場合は、製糸プロセスにおける生産性が大きく低下し、満足な性能が得られなくなる。また、（Ｔｉ＋Ｐ）が２００を越える場合には、触媒に起因する異物が少量ではあるが発生し好ましくない。
【００５９】
上記式（６）、（７）の範囲は好ましくは（６）式中の（Ｐ／Ｔｉ）は１．０〜４．５の範囲、（７）式中の（Ｔｉ＋Ｐ）は１２〜１５０の範囲であり、更に好ましくは、（６）式中の（Ｐ／Ｔｉ）は２．０〜４．０の範囲、（７）式中の（Ｔｉ＋Ｐ）は１５〜１００の範囲である。
【００６０】
本発明の製造方法において、前記触媒系を用いて行われる重合反応は、２３０〜３２０℃の温度において、常圧下、又は減圧下、好ましくは０．０５Ｐａ〜０．２ＭＰａにおいて、これらの条件を組み合わせて、１５〜３００分間重合反応させることが好ましい。
【００６１】
本発明の常圧染色用ポリエステルに含まれるポリマーに可溶性のチタン元素量は全ジカルボン酸成分に対し５〜７０ｐｐｍの範囲にあるようにする必要がある。ここで、「ポリマーに可溶性のチタン元素量」とは酸化チタンのような粒子を除いたチタン元素の量を意味し、該チタン元素量が５ｐｐｍ未満の場合は重合反応が遅くなり、７０ｐｐｍを超える場合は得られるポリエステルの色調が、不良になり、かつその耐熱性が低下することがあり好ましくない。チタン元素量は７〜６０ｐｐｍの範囲が好ましく、１０〜５０ｐｐｍの範囲が更に好ましい。
【００６２】
本発明の常圧可染用ポリエステルの固有粘度については特に限定はないが、オルトクロロフェノール溶媒中３５℃で測定した固有粘度が、０．４０〜０．８０の範囲のものが好ましく使用される。
【００６３】
本発明の常圧可染用ポリエステル中には、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。
【００６４】
上述した本発明のポリエステルを製造するにあたっては、重合触媒として前記の触媒系を用いる限り、特に限定はなく、テレフタル酸をエチレングリコールと直接エステル化させた後、重合させる方法、テレフタル酸のエステル形成性誘導体をエチレングリコールとエステル交換反応させた後、重合させる方法のいずれを採用しても良いが、芳香族ジカルボン酸のエステル形成性誘導体を原料とし、エステル交換反応を経由する製造方法とすることが好ましい。該方法は、テレフタル酸を原料とする製造方法に比較し、重合反応中に安定剤として添加したリン化合物の飛散が少ないという利点がある。
【００６５】
また、テレフタル酸ジメチルを出発原料とする製造方法では、チタン化合物成分の一部及び／又は全量を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合反応触媒との二つの触媒として兼用させる方法が、チタン化合物成分の添加量を低減できることから好ましく、この場合、テレフタル酸ジメチルは使用するテレフタル酸成分の９０モル％以上とすることが好ましい。
【００６６】
なお、該エステル交換反応を行う場合には通常は常圧下で実施されるが、０．０５〜０．２０ＭＰａの加圧下に実施すると、チタン化合物成分の触媒作用による反応が更に促進され、かつ副生物のジプロピレングリコールが大量に発生することもないので、熱安定性などの特性が更に良好なものとなる。
【００６７】
本発明の常圧染色用可染性ポリエステル繊維を製造するにあたっては特に限定はなく、従来公知の溶融紡糸方法が用いて製造することができる。例えばポリエステルを２７０℃〜３００℃の範囲で溶融紡糸して製造することが好ましく、溶融紡糸の速度は４００〜５０００ｍ／分で紡糸することが好ましい。紡糸速度がこの範囲にあると、得られる繊維の強度も十分なものであると共に、安定して巻き取りを行うこともできる。また延伸はポリエステル繊維を巻き取ってから、あるいは一旦巻き取ることなく連続的に延伸処理することによって、延伸糸を得ることができる。更に本発明のポリエステル繊維は風合を高める為に、アルカリ減量処理も好ましく実施される。
【００６８】
本発明のポリエステル繊維を製造する際において、紡糸時に使用する口金の形状について制限は無く、円形、異形、中実、中空等のいずれも採用することができる。
【００６９】
本発明におけるポリエステル繊維は、従来使用される分散染料で染色することができ、鮮明かつ色調に優れたポリエステル繊維を得ることができる。
【００７０】
【実施例】
以下、実施例を挙げてさらに具体的に説明するが、本発明はこれにより何ら限定を受けるものでは無い。なお実施例中の部は重量部を示す。また各種値は下記の方法に従って求めた。
（１）固有粘度：
オルトクロルフェノールを溶媒として３５℃で測定し、その相対粘度から常法により求めた。
（２）色調（Ｌ値及びｂ値）：
ポリマーチップを１６０℃、１時間乾燥結晶化処理後、日本電色工業株式会社製測色色差計Ｚ−１００１ＤＰを用いて測定した。Ｌ値は明度を示し、その数値が大きいほど明度が高いことを示し、ｂ値はその値が大きいほど黄色味の度合いが大きいことを示す。
（３）ポリエステル中のチタン、リン、アンチモン含有量：
ポリエステル中の残留触媒金属濃度は、粒状のポリマーサンプル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形体を作成し、蛍光Ｘ線装置（理学電機工業株式会社製３２７０Ｅ型）を用いて求めた。
（４）ポリエステル中の共重合成分量：
サンプルを重水素化トリフルオロ酢酸／重水素化クロロホルム＝５０／５０重量比の混合溶媒に溶解後、日本電子株式会社製ＪＥＯＬ Ａ−６００ 超伝導ＦＴ−ＮＭＲを用いて核磁気共鳴スペクトル（^１Ｈ−ＮＭＲ）を測定し、そのスペクトルパターンから常法に従って共重合成分量を定量した。
（５）ガラス転移温度：
示差走査熱量計（ＤＳＣ）としてＴＡ Ｉｎｓｔｒｕｍｅｎｔｓ社製 ＤＳＣ２０１０ Ｄｉｆｆｅｒｅｎｔｉａｌ Ｓｃａｎｎｉｎｇ Ｃａｌｏｒｉｍｅｔｅｒを用いて、１０℃／分の昇温速度で２６０℃まで昇温したサンプルを０℃に冷却した試験管中で急冷し非晶状態にしたサンプルを更に１０℃／分の昇温速度で昇温し、ＪＩＳ Ｋ７１２１に準じて中間点ガラス転移温度を測定した。
（６）パック圧上昇評価：
紡糸口金直上に２４００メッシュの径２５ｍｍの金網を装着した紡糸機に２８５℃でポリエステルチップを３０ｇ／分で７日間連続的に供給した前後のパック圧の上昇度合いを、１日当たりのパック圧昇圧に換算して求めた。
（７）紡糸口金に発生する付着物の層：
ポリエステルをチップとなし、これを２８５℃で溶融し、孔径０．１５ｍｍφ、孔数１２個の紡糸口金から吐出し、６００ｍ／分で２日間紡糸し、口金の吐出口外縁に発生する付着物の層の高さを測定した。この付着物層の高さが大きいほど吐出されたポリエステルメルトのフィラメント状流にベンディングが発生しやすく、このポリエステルの成形性は低くなる。すなわち、紡糸口金に発生する付着物層の高さは、当該ポリエステルの成形性の指標である。
（８）常圧染色性評価：
繊維を布帛に形成した試験片を市販の分散染料Ｓｕｍｉｋａｒｏｎ ＮａｖｙＢｌｕｅ Ｓ−２ＧＬ（住友化学工業株式会社製）の４％ｏｗｆ溶液中、９５℃で１時間、浴比１：５０で染色を行い、次式により染着率を求めた。染着率は次式より求めた。
【００７１】
【数８】
染着率＝（ＯＤ_０−ＯＤ_１）÷ＯＤ_０ × １００ （％）
式中、ＯＤ_０は染色前染液の５７６ｎｍの吸光度を、ＯＤ_１は染色後染液の５７６ｎｍの吸光度をそれぞれ表す。本発明では、染着率９５％以上のものを常圧可染性良好と判断する。
【００７２】
［参考例］トリメリット酸チタンの合成方法：
無水トリメリット酸のエチレングリコール溶液（０．２％）にテトラ−ｎ−ブチルチタネートを無水トリメリット酸に対して１／２モル添加し、空気中常圧下で８０℃に保持して６０分間反応させて、その後、常温に冷却し、１０倍量のアセトンによって生成触媒を再結晶化させ、析出物をろ紙によって濾過し、１００℃で２時間乾燥させて、目的とする化合物を得た。
【００７３】
［実施例１］
テレフタル酸ジメチル１００部とエチレングリコール７０部との混合物に、テトラ−ｎ−ブチルチタネート０．００９部を加圧反応が可能なステンレス製容器に仕込み、０．０７ＭＰａの加圧を行い１４０℃から２４０℃に昇温しながらエステル交換反応させた後、セバシン酸１０．３部を添加して３０分間エステル化反応させた後、テトラ−ｎ−ブチルチタネート０．００６部、トリエチルホスホノアセテート０．０３５部、テラゾールブルー０．００００５５重量部を添加し、エステル交換反応を終了させた。
【００７４】
その後、反応生成物を重合反応容器に移し、２９０℃まで昇温し、２６．６７Ｐａ以下の高真空で重合反応を行って、固有粘度０．７０のポリエステルを得た。得られたチップを１６０℃×４ｈｒの条件で乾燥後、２８５℃にて紡糸し、延伸倍率４．０倍で延伸して８３．２５ｄｔｅｘ／３６ｆｉｌのマルチフィラメントを得た。更に得られたマルチフィラメントは常法により筒編みにした後、常圧染色性評価を実施した。結果を表１に示す。
【００７５】
［実施例２及び比較例１］
実施例１において、触媒を表１記載のとおりに変更したこと以外は同様の操作を行った。結果を表１に示す。ただし、比較例１はエステル交換反応終了後に添加したテトラ−ｎ−ブチルチタネート０．００６部から代えて、三酸化二アンチモンを０．０４５部を使用した。
【００７６】
［実施例３〜７、比較例２〜３］
実施例１において、触媒、共重合成分を表１記載のとおりに変更したこと以外は同様の操作を行った。結果を表１に示す。
【００７７】
【表１】

【００７８】
【発明の効果】
本発明によれば、チタン化合物を触媒として使用した際の従来技術の欠点であった色相の悪化を解消し、口金異物の少ない安定した紡糸を可能とし、ポリエステルが持つ、優れた特性を保持しながら、色相が優れた常圧染色用ポリエステル繊維を提供することができる。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a normal pressure dyeing polyester and a fiber thereof, and more particularly, to a normal pressure dyeing polyester and a fiber which is polymerized by using a specific titanium compound and a phosphorus compound and has an excellent color tone and does not contain Sb metal.
[0002]
[Prior art]
Polyester, especially polyethylene terephthalate, polyethylene naphthalate, polytrimethylene terephthalate and polytetramethylene terephthalate are widely used in fibers, films and other molded products because of their excellent mechanical, physical and chemical properties. I have. However, polyester cannot be said to have good dyeability as a fiber for clothing, and dyeing using a disperse dye usually uses a dyeing step under high-pressure conditions, which is not a reasonable method in the production process. .
[0003]
Conventionally, in order to compensate for such a defect, there has been known a method of producing a modified polyester having excellent dyeability at normal pressure by copolymerizing an aliphatic dicarboxylic acid, a polyalkylene glycol, or the like (for example, Patent Document 1, 2 etc.).
[0004]
Such polyesters for normal pressure dyeing are usually subjected to a direct esterification reaction of terephthalic acid and ethylene glycol, a transesterification reaction of a lower alkyl ester of terephthalic acid such as dimethyl terephthalate and ethylene glycol, or a terephthalic acid. And ethylene oxide to produce an ethylene glycol ester of terephthalic acid and / or a low polymer thereof. Then, the reaction product is heated under reduced pressure in the presence of a polymerization catalyst until a predetermined polymerization degree is reached. It has been manufactured.
[0005]
It is well known that the type of catalyst used in these polymerization reaction steps greatly affects the reaction rate and the quality of the resulting polyester. Cationic dyeable polyesters can be polymerized using the same polymerization catalysts as known polyesters.For example, an antimony compound has excellent polymerization catalyst performance, and a polyester having a good color tone is obtained. The most widely used for such reasons.
[0006]
However, when the antimony compound is used as a polymerization catalyst, when the polyester is continuously melt-spun for a long time, the reduced antimony metal becomes a foreign substance, and the pressure of the spinning filtration unit (hereinafter, may be simply referred to as a pack pressure). )) Rises, and foreign matter (hereinafter, simply referred to as the foreign matter of the die) adheres and accumulates around the die hole, causing a bending phenomenon (bending) of the flow of the molten polymer, which causes spinning. In addition, there is a problem of moldability such as generation of fluff and / or thread breakage in the stretching step, which has caused a significant decrease in productivity.
[0007]
As a polymerization catalyst other than the antimony compound, it has been proposed to use a titanium compound such as titanium tetrabutoxide. Can be solved, but a new problem arises in that the obtained polyester itself is colored yellow and the melt heat stability is poor.
[0008]
In order to solve the above-mentioned coloring problem, it is common practice to add a cobalt compound to polyester to suppress yellowing. Certainly, the color tone (b value) of the polyester can be improved by adding the cobalt compound, but the problem that the addition of the cobalt compound lowers the melt heat stability of the polyester and the polymer is easily decomposed. There is.
[0009]
As other titanium compounds, use of titanium hydroxide as a catalyst for producing polyester (for example, see Patent Document 3) and use of α-titanic acid as a catalyst for producing polyester (for example, see Patent Document 4). It has been disclosed. However, in the former method, powdering of titanium hydroxide is not easy. On the other hand, in the latter method, α-titanic acid is easily deteriorated, so that its storage and handling are not easy. In addition, it is difficult to obtain a polymer having a good color tone (b value).
[0010]
Further, a product obtained by reacting a titanium compound with trimellitic acid is used as a catalyst for producing a polyester (for example, see Patent Document 5), or a reaction between a titanium compound and a phosphite is performed. It is disclosed that the obtained product is used as a catalyst for producing polyester (for example, see Patent Document 6).
[0011]
Certainly, according to this method, although the melt heat stability of the polyester is improved to some extent, the color tone of the obtained polymer is not sufficient, and thus further improvement of the polymer color tone is desired.
[0012]
It has also been proposed to use a catalyst obtained by reacting a titanium compound with a specific phosphonic acid compound, and although the polymer color tone has been improved, the dyeability of polyester has not been improved (for example, see Patent Document 7). .
[0013]
As described above, it is effective means not to use antimony as a catalyst to suppress foreign matter in a die. However, in a method not using antimony, the color of the yarn is reduced. Could not.
[0014]
Therefore, polyester fibers which do not use antimony as a catalyst and have excellent hue have been demanded.
[0015]
[Patent Document 1]
JP-A-9-324322
[Patent Document 2]
JP 10-330467 A
[Patent Document 3]
JP-B-48-2229 gazette
[Patent Document 4]
Japanese Patent Publication No. 47-26597
[Patent Document 5]
JP-B-59-46258 [0020]
[Patent Document 6]
JP-A-58-38722.
[Patent Document 7]
WO 01/00706 Pamphlet [0022]
[Problems to be solved by the invention]
An object of the present invention is to improve the hue having excellent color tone, an extremely small increase in pack pressure and generation of deposits on a die even after continuous spinning for a long time, excellent moldability, and high productivity. To provide polyester and fibers for normal pressure dyeing.
[0023]
[Means for Solving the Problems]
The inventor of the present invention has conducted intensive studies in view of the above-described prior art in order to achieve the above object, and has completed the present invention.
[0024]
That is, an object of the present invention is to provide a dicarboxylic acid component having at least 80 mol% of ethylene terephthalate of a component constituting a polyester and having a saturated aliphatic chain and / or a saturated alicyclic chain having 2 to 20 carbon atoms ( A), a glycol component (B) having a saturated aliphatic chain and / or a saturated alicyclic chain having 3 to 15 carbon atoms, and a saturated aliphatic chain and / or a saturated alicyclic chain having 20 to 40 carbon atoms. The copolymerization amounts of the dicarboxylic acid component (C) and the polyoxyalkylene glycol component (D) having a molecular weight of 200 to 6000 simultaneously satisfy the following mathematical formulas (1) to (5), and at the time of polyester polymerization. As the catalyst, a titanium compound represented by the following general formula (I), a titanium compound represented by the following general formula (I) and an aromatic polycarboxylic acid represented by the following general formula (II) A catalyst system substantially consisting of an unreacted mixture of a titanium compound component containing at least one selected from the group consisting of products obtained by reacting with a phosphorus compound represented by the following general formula (III): The amount of titanium element soluble in the polymer contained in the polyester obtained by simultaneously using the expressions (6) and (7) is in the range of 5 to 70 ppm based on the total dicarboxylic acid component, This can be achieved by dyeing polyesters.
[0025]
[Equation 3]

[0026]
Embedded image

[0027]
Embedded image

[0028]
Embedded image

[0029]
(Equation 4)

[0030]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described in detail.
The polyester for atmospheric pressure dyeing of the present invention comprises a dicarboxylic acid component (A) having a saturated aliphatic chain having 2 to 20 carbon atoms and / or a saturated alicyclic chain and a saturated aliphatic chain having 3 to 15 carbon atoms and / or A glycol component having a saturated alicyclic chain (B), a dicarboxylic acid component having a saturated aliphatic chain having 20 to 40 carbon atoms and / or a saturated alicyclic chain (C), and a polyoxyalkylene glycol component having a molecular weight of 200 to 6000 It is necessary that each copolymerization amount of (D) satisfies the following mathematical expressions (1) to (5) at the same time.
[0031]
(Equation 5)

[0032]
Here, specific examples of the dicarboxylic acid component (A) having a saturated aliphatic chain and / or a saturated alicyclic chain having 2 to 20 carbon atoms represented by the formula A include oxalic acid, malonic acid, and succinic acid. Examples thereof include acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid and the like, with sebacic acid being particularly preferred.
[0033]
Examples of the glycol component (B) having a saturated aliphatic chain and / or a saturated alicyclic chain having 3 to 20 carbon atoms represented by the above formula B include trimethylene glycol, tetramethylene glycol, pentamethylene glycol, and hexamethylene glycol. And heptamethylene glycol, octamethylene glycol, nonamethylene glycol, decamethylene glycol, cyclohexane dimethanol, neopentylene glycol, etc., with hexamethylene glycol being particularly preferred.
[0034]
Specific examples of the dicarboxylic acid component (C) having a saturated aliphatic chain having 20 to 40 carbon atoms and / or a saturated alicyclic chain represented by the formula C include dimer acids and the like. As the acid, a dimer acid produced using linoleic acid or oleic acid as a starting material is preferably used.
[0035]
Examples of the polyoxyalkylene glycol component (D) having a molecular weight of 200 to 6000 represented by the formula D include polyethylene glycol, polypropylene glycol, polytetramethylene glycol, and the like. In particular, polyethylene glycol having a molecular weight of 400 to 4000, and a molecular weight of 400 ~ 2000 polytetramethylene glycols are preferably used.
[0036]
The copolymerization amount of the dicarboxylic acid component (A) and the glycol component (B) represented by the above formulas A and B must each be 20 mol% or less. If the copolymerization amount exceeds 20 mol%, the strength and heat resistance of the obtained polyester fiber are undesirably reduced. The copolymerization amount is preferably in the range of 17 mol% or less, more preferably in the range of 15 mol%. Further, the copolymerization amount of the dicarboxylic acid component (C) represented by the above formula C needs to be 20% by weight or less. If the copolymerization amount exceeds 20% by weight, the strength and heat resistance of the obtained polyester fiber are undesirably reduced. The copolymerization amount is preferably in the range of 17% by weight or less, more preferably in the range of 15% by weight. Further, the copolymerization amount of the polyoxyalkylene glycol component (D) represented by the above formula D needs to be 15% by weight or less. If the copolymerization amount exceeds 15% by weight, the strength, heat resistance and light resistance of the obtained polyester fiber are undesirably reduced. The copolymerization amount is preferably in the range of 12% by weight or less, more preferably in the range of 10% by weight.
[0037]
The sum of the copolymerization amounts of the above formulas A, B, C, and D needs to be in the range of 5% to 20%. When the total amount of the copolymerization is less than 5%, the normal pressure dyeing property of the finally obtained fiber becomes insufficient, and when it exceeds 20%, the strength, heat resistance and light resistance of the obtained polyester fiber. Is undesirably reduced. The copolymerization amount is preferably in the range of 6 to 17%, more preferably in the range of 7 to 15%.
[0038]
The polyester for normal pressure dyeing of the present invention has a terephthalic acid component, an ethylene glycol component, a saturated aliphatic chain having 2 to 20 carbon atoms and / or a saturated alicyclic group in a range not impairing its properties, preferably in a range of 5 mol% or less. A dicarboxylic acid component having a chain (A), a saturated aliphatic chain having 3 to 20 carbon atoms and / or a glycol component having a saturated alicyclic chain (B), and a saturated aliphatic chain having 20 to 40 carbon atoms and / or saturated Components other than the dicarboxylic acid component (C) having an alicyclic chain and the polyoxyalkylene glycol component (D) having a molecular weight of 200 to 6000 may be copolymerized. For example, naphthalenedicarboxylic acid, orthophthalic acid, diphenyldicarboxylic acid, Diphenyl ether dicarboxylic acid, diphenyl sulfone dicarboxylic acid, benzophenone dicarboxylic acid, phenylindane dicarboxylic acid, Aromatic dicarboxylic acid components such as -sulfoxyisophthalic acid metal salt, 5-sulfoxyisophthalic acid phosphonium salt, o-xylylene glycol, m-xylylene glycol, p-xylylene glycol, 1,4-bis (2- (Hydroxyethoxy) benzene, 1,4-bis (2-hydroxyethoxyethoxy) benzene, 4,4′-bis (2-hydroxyethoxy) biphenyl, 4,4′-bis (2-hydroxyethoxyethoxy) biphenyl, 2, 2-bis [4- (2-hydroxyethoxy) phenyl] propane, 2,2-bis [4- (2-hydroxyethoxyethoxy) phenyl] propane, 1,3-bis (2-hydroxyethoxy) benzene, 1, 3-bis (2-hydroxyethoxyethoxy) benzene, 1,2-bis (2-hydroxyethoxy) B) benzene, 1,2-bis (2-hydroxyethoxyethoxy) benzene, 4,4'-bis (2-hydroxyethoxy) diphenylsulfone, 4,4'-bis (2-hydroxyethoxyethoxy) diphenylsulfone, etc. Examples thereof include aromatic glycol components, hydroquinone, 2,2-bis (4-hydroxyphenyl) propane, diphenols such as resorcinol, catechol, dihydroxynaphthalene, dihydroxybiphenyl and dihydroxydiphenylsulfone. These may be used alone or in combination of two or more.
[0039]
The polyester for atmospheric pressure dyeing of the present invention comprises a titanium compound represented by the following general formula (I), and a titanium compound represented by the following general formula (I) and an aromatic polyester represented by the following general formula (II). A substantially unreacted mixture of a titanium compound component containing at least one selected from the group consisting of a product obtained by reacting a polyvalent carboxylic acid or an anhydride thereof with a phosphorus compound represented by the following general formula (III): It is necessary that the catalyst system is polymerized by using the following catalyst system so as to simultaneously satisfy the following mathematical expressions (6) and (7).
[0040]
Embedded image

[0041]
Embedded image

[0042]
Embedded image

[0043]
(Equation 6)

[0044]
In the production method of the present invention, the titanium compound component used as a catalyst in the polymerization reaction requires the use of a titanium compound soluble in a polymer from the viewpoint of reducing foreign substances caused by the catalyst. As the components, a compound represented by the following general formula (I) or a compound represented by the following general formula (II) and an aromatic polycarboxylic acid represented by the following general formula (II) or an anhydride thereof are used. It must be a reacted product.
[0045]
Embedded image

[0046]
Embedded image

[0047]
Here, as the titanium compound represented by the general formula (I), specifically, tetraisopropoxytitanium, tetrapropoxytitanium, tetra-n-butoxytitanium, tetraethoxytitanium, tetraphenoxytitanium, octaalkyltrititanate, And hexaalkyl dititanate are preferably used.
[0048]
In the production method of the present invention, the aromatic polycarboxylic acid represented by the general formula (II) or an anhydride thereof reacted with the titanium compound includes phthalic acid, trimellitic acid, hemi-mellitic acid, and pyromellitic acid. Acids and anhydrides thereof are preferably used.
[0049]
When reacting the titanium compound with an aromatic polycarboxylic acid or an anhydride thereof, a part or all of the aromatic polycarboxylic acid or an anhydride thereof is dissolved in a solvent, and the titanium compound is added to the mixed solution. It is carried out by dropping and heating 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. The reaction pressure at this time is not particularly limited, and normal pressure is sufficient. As a solvent for dissolving the aromatic polycarboxylic acid or its anhydride, any of ethanol, ethylene glycol, trimethylene glycol, tetramethylene glycol, benzene, xylene and the like can be used as desired.
[0050]
Here, the reaction molar ratio of the titanium compound and the aromatic polycarboxylic acid or its anhydride is not particularly limited, but if the proportion of the titanium compound is too high, the color tone of the obtained polyester is deteriorated or the softening point is reduced. May decrease, and conversely, if the proportion of the titanium compound is too low, the polymerization reaction may be difficult to proceed. Therefore, the reaction molar ratio of the titanium compound to the aromatic polycarboxylic acid or its anhydride is preferably in the range of 2/1 to 2/5.
[0051]
In the catalyst system used as a polymerization catalyst in the production method of the present invention, the above-mentioned titanium compound component substantially consists of an unreacted mixture with a phosphorus compound represented by the following general formula (III).
[0052]
Embedded image

[0053]
Examples of the phosphorus compound (phosphonate compound) of the general formula (III) include carbomethoxymethanephosphonic acid, carbethoxymethanephosphonic acid, carbopropoxymethanephosphonic acid, carboptoxymethanephosphonic acid, carbomethoxy-phosphono-phenylacetic acid, It is preferably selected from the dimethyl, diethyl, dipropyl and dibutyl esters of ethoxy-phosphono-phenylacetic acid, carboxy-phosphono-phenylacetic acid and carboxy-phosphono-phenylacetic acid.
[0054]
Since the above-mentioned phosphonate compound proceeds relatively slowly with the titanium compound as compared with the phosphorus compound usually used as a stabilizer, the duration of the catalytic activity of the titanium compound during the reaction is long, and as a result, The amount of the titanium compound added to the polyester can be reduced. Further, even if a large amount of a stabilizer is added to the catalyst system containing the phosphorus compound of the general formula (III), the resulting polyester does not deteriorate in thermal stability and does not deteriorate its color tone.
[0055]
Further, the above-mentioned catalyst system needs to simultaneously satisfy the following mathematical expressions (6) and (7).
[0056]
(Equation 7)

[0057]
Here, when (P / Ti) is less than 0.65, the hue of the polyester is yellowish, which is not preferable. On the other hand, when (P / Ti) exceeds 5, the polymerization reactivity of the polyester is greatly reduced, and it becomes difficult to obtain the desired polyester. Although the proper range of (P / Ti) is characteristically narrower than that of a normal metal catalyst system, when it is within the proper range, an effect which has not been achieved conventionally can be obtained as in the present invention.
[0058]
On the other hand, when (Ti + P) is less than 10, productivity in the spinning process is greatly reduced, and satisfactory performance cannot be obtained. On the other hand, when (Ti + P) exceeds 200, a small amount of foreign matter due to the catalyst is generated, which is not preferable.
[0059]
The ranges of the above formulas (6) and (7) are preferably such that (P / Ti) in the formula (6) is in the range of 1.0 to 4.5, and (Ti + P) in the formula (7) is in the range of 12 to 150. (P / Ti) in the formula (6) is more preferably in the range of 2.0 to 4.0, and (Ti + P) in the formula (7) is more preferably in the range of 15 to 100.
[0060]
In the production method of the present invention, the polymerization reaction carried out using the catalyst system is a combination of these conditions at a temperature of 230 to 320 ° C. under normal pressure or under reduced pressure, preferably at 0.05 Pa to 0.2 MPa. Preferably, the polymerization reaction is performed for 15 to 300 minutes.
[0061]
It is necessary that the amount of titanium element soluble in the polymer contained in the polyester for normal pressure dyeing of the present invention is in the range of 5 to 70 ppm based on all dicarboxylic acid components. Here, “the amount of the titanium element soluble in the polymer” means the amount of the titanium element excluding particles such as titanium oxide, and when the titanium element amount is less than 5 ppm, the polymerization reaction is slowed and exceeds 70 ppm. In such a case, the color tone of the obtained polyester may be poor, and the heat resistance may be undesirably reduced. The titanium element content is preferably in the range of 7 to 60 ppm, more preferably in the range of 10 to 50 ppm.
[0062]
The intrinsic viscosity of the polyester for normal pressure dyeing of the present invention is not particularly limited, but the intrinsic viscosity measured at 35 ° C. in an orthochlorophenol solvent is preferably from 0.40 to 0.80. .
[0063]
In the normal pressure dyeable polyester of the present invention, if necessary, a small amount of additives such as 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.
[0064]
In producing the above-mentioned polyester of the present invention, there is no particular limitation as long as the above-mentioned catalyst system is used as a polymerization catalyst, a method of directly esterifying terephthalic acid with ethylene glycol and then polymerizing the same, forming an ester of terephthalic acid. Any method may be employed in which the ester derivative is subjected to a transesterification reaction with ethylene glycol and then polymerized.However, a method in which an ester-forming derivative of an aromatic dicarboxylic acid is used as a raw material and a transesterification reaction is used. Is preferred. This method has an advantage that the phosphorus compound added as a stabilizer during the polymerization reaction is less scattered than the production method using terephthalic acid as a raw material.
[0065]
In addition, in the production method using dimethyl terephthalate as a starting material, a part and / or the whole amount of the titanium compound component is added before the start of the transesterification reaction, and the titanium compound component is also used as the two catalysts, the transesterification catalyst and the polymerization reaction catalyst. The method is preferable because the amount of the titanium compound component can be reduced, and in this case, dimethyl terephthalate is preferably 90 mol% or more of the terephthalic acid component used.
[0066]
When the transesterification is carried out, it is usually carried out under normal pressure. However, when carried out under a pressure of 0.05 to 0.20 MPa, the reaction by the catalytic action of the titanium compound component is further promoted, and Since a large amount of biological dipropylene glycol is not generated, properties such as thermal stability are further improved.
[0067]
In producing the dyeable polyester fiber for atmospheric pressure dyeing of the present invention, there is no particular limitation, and it can be produced by a conventionally known melt spinning method. For example, the polyester is preferably produced by melt-spinning in the range of 270 ° C to 300 ° C, and the melt-spinning speed is preferably 400 to 5000 m / min. When the spinning speed is in this range, the strength of the obtained fiber is sufficient, and the winding can be performed stably. In the drawing, a drawn yarn can be obtained by winding the polyester fiber or by continuously drawing without once winding. Further, the polyester fiber of the present invention is preferably subjected to an alkali weight reduction treatment in order to enhance the feeling.
[0068]
In producing the polyester fiber of the present invention, there is no limitation on the shape of the die used at the time of spinning, and any of a circular shape, a deformed shape, a solid shape, a hollow shape and the like can be adopted.
[0069]
The polyester fiber in the present invention can be dyed with a conventionally used disperse dye, and a clear and excellent color tone polyester fiber can be obtained.
[0070]
【Example】
Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited thereto. Parts in the examples are parts by weight. Various values were determined according to the following methods.
(1) Intrinsic viscosity:
It was measured at 35 ° C. using orthochlorophenol as a solvent, and the relative viscosity was determined by a conventional method.
(2) Color tone (L value and b value):
The polymer chip was dried and crystallized at 160 ° C. for 1 hour, and then measured using a colorimetric colorimeter Z-1001DP manufactured by Nippon Denshoku Industries Co., Ltd. The L value indicates lightness, and the larger the numerical value, the higher the lightness, and the larger the b value, the greater the yellowness.
(3) Titanium, phosphorus and antimony content in polyester:
The residual catalyst metal concentration in the polyester was determined by heating and melting a granular polymer sample on an aluminum plate, then preparing a test molded body having a flat surface with a compression press, and using a fluorescent X-ray apparatus (3270E manufactured by Rigaku Corporation). (Type).
(4) Amount of copolymer component in polyester:
After dissolving the sample in a mixed solvent of deuterated trifluoroacetic acid / deuterated chloroform = 50/50 weight ratio, a nuclear magnetic resonance spectrum ( ¹ H) was measured using JEOL A-600 superconducting FT-NMR manufactured by JEOL Ltd. -NMR), and the amount of the copolymer component was quantified from the spectrum pattern according to a conventional method.
(5) Glass transition temperature:
Using a DSC 2010 Differential Scanning Calorimeter manufactured by TA Instruments as a differential scanning calorimeter (DSC), the sample heated to 260 ° C. at a rate of 10 ° C./min was quenched in a test tube cooled to 0 ° C. and amorphous. The sample in the state was further heated at a heating rate of 10 ° C./min, and the midpoint glass transition temperature was measured according to JIS K7121.
(6) Pack pressure rise evaluation:
The degree of increase in pack pressure before and after the polyester chips were continuously supplied at 30 g / min at 285 ° C. for 7 days at 285 ° C. to a spinning machine equipped with a 2400 mesh 25 mm diameter wire mesh directly above the spinneret was changed to pack pressure increase per day. Converted and found.
(7) Layer of deposits generated on spinneret:
Polyester is made into a chip, which is melted at 285 ° C., discharged from a spinneret having a hole diameter of 0.15 mmφ and 12 holes, spun at 600 m / min for 2 days, and adhered to the outer edge of the outlet of the nozzle. The layer height was measured. As the height of the deposit layer increases, bending tends to occur in the filamentary flow of the discharged polyester melt, and the moldability of the polyester decreases. That is, the height of the deposit layer generated on the spinneret is an index of the moldability of the polyester.
(8) Evaluation of normal pressure dyeability:
A test piece obtained by forming a fiber on a fabric was dyed in a 4% owf solution of a commercially available disperse dye Sumikaron NavyBlue S-2GL (manufactured by Sumitomo Chemical Co., Ltd.) at 95 ° C. for 1 hour at a bath ratio of 1:50. The dyeing rate was determined by the formula. The dyeing rate was determined by the following equation.
[0071]
(Equation 8)
Somegiritsu _{= (OD 0 -OD 1) ÷} OD 0 × 100 (%)
In the formula, OD ₀ represents the absorbance at 576 nm of the pre-stained liquor, and OD ₁ represents the absorbance at 576 nm of the post-stain liquor. In the present invention, those having a dyeing rate of 95% or more are judged to have good normal-pressure dyeability.
[0072]
[Reference Example] Synthesis method of titanium trimellitate:
To a solution of trimellitic anhydride in ethylene glycol (0.2%) was added 1/2 mole of tetra-n-butyl titanate with respect to trimellitic anhydride, and the mixture was reacted at 80 ° C. in the air under atmospheric pressure for 60 minutes. Thereafter, the mixture was cooled to room temperature, the produced catalyst was recrystallized with 10 times the amount of acetone, and the precipitate was filtered with filter paper and dried at 100 ° C. for 2 hours to obtain the desired compound.
[0073]
[Example 1]
To a mixture of 100 parts of dimethyl terephthalate and 70 parts of ethylene glycol, 0.009 part of tetra-n-butyl titanate is charged into a stainless steel container capable of performing a pressure reaction, and pressurized at 0.07 MPa to 140 ° C. to 240 ° C. After the transesterification reaction while raising the temperature to 10 ° C., 10.3 parts of sebacic acid was added, and the esterification reaction was performed for 30 minutes. Then, 0.006 parts of tetra-n-butyl titanate and 0.035 parts of triethylphosphonoacetate were added. And 0.000055 parts by weight of terazole blue were added to terminate the transesterification reaction.
[0074]
Thereafter, the reaction product was transferred to a polymerization reaction vessel, the temperature was raised to 290 ° C., and the polymerization reaction was performed under a high vacuum of 26.67 Pa or less to obtain a polyester having an intrinsic viscosity of 0.70. The obtained chip was dried under the conditions of 160 ° C. × 4 hr, spun at 285 ° C., and stretched at a draw ratio of 4.0 to obtain a multifilament of 83.25 dtex / 36 fill. Further, the obtained multifilament was knitted in a tubular manner by a conventional method, and then evaluated under normal pressure dyeing properties. Table 1 shows the results.
[0075]
[Example 2 and Comparative Example 1]
In Example 1, the same operation was performed except that the catalyst was changed as shown in Table 1. Table 1 shows the results. However, in Comparative Example 1, 0.045 parts of diantimony trioxide was used instead of 0.006 parts of tetra-n-butyl titanate added after the end of the transesterification reaction.
[0076]
[Examples 3 to 7, Comparative Examples 2 to 3]
The same operation was performed as in Example 1, except that the catalyst and the copolymerization component were changed as shown in Table 1. Table 1 shows the results.
[0077]
[Table 1]

[0078]
【The invention's effect】
According to the present invention, the deterioration of hue, which is a drawback of the prior art when a titanium compound is used as a catalyst, is eliminated, stable spinning with a small amount of foreign matter in a die is achieved, and the excellent properties of polyester are maintained. However, it is possible to provide a normal pressure dyeing polyester fiber having an excellent hue.

Claims (6)

At least 80 mol% of the components constituting the polyester is ethylene terephthalate,
A dicarboxylic acid component (A) having a saturated aliphatic chain and / or a saturated alicyclic chain having 2 to 20 carbon atoms, and a glycol component having a saturated aliphatic chain and / or a saturated alicyclic chain having 3 to 15 carbon atoms (B), a dicarboxylic acid component (C) having a saturated aliphatic chain and / or a saturated alicyclic chain having 20 to 40 carbon atoms, and a polyoxyalkylene glycol component (D) having a molecular weight of 200 to 6000. The copolymerization amount simultaneously satisfies the following formulas (1) to (5),
And, as a catalyst at the time of polyester polymerization, a titanium compound represented by the following general formula (I), a titanium compound represented by the following general formula (I) and an aromatic polyvalent represented by the following general formula (II) A substantially unreacted mixture of a titanium compound component containing at least one selected from the group consisting of a product obtained by reacting a carboxylic acid or an anhydride thereof with a phosphorus compound represented by the following general formula (III): The amount of titanium element soluble in the polymer contained in the polyester obtained by using the catalyst system satisfying the following formulas (6) and (7) in the range of 5 to 70 ppm based on all dicarboxylic acid components. Polyester for normal pressure dyeing.

The polyester according to claim 1, wherein the dicarboxylic acid component (A) having a saturated aliphatic chain and / or a saturated alicyclic chain having 2 to 20 carbon atoms is sebacic acid. The polyester according to claim 1, wherein the glycol component (B) having a saturated aliphatic chain and / or a saturated alicyclic chain having 3 to 15 carbon atoms is hexamethylene glycol. The polyester according to claim 1, wherein the dicarboxylic acid component (C) having a saturated aliphatic chain and / or a saturated alicyclic chain having 20 to 40 carbon atoms is a dimer acid. The polyester according to claim 1, wherein the polyoxyalkylene glycol component (D) having a molecular weight of 200 to 6000 is selected from polyethylene glycol and polytetramethylene glycol. A polyester fiber for normal pressure dyeing obtained by melt-spinning the polyester according to claim 1.