JP4710141B2

JP4710141B2 - Polyester composite yarn for high stretch woven and knitted fabric

Info

Publication number: JP4710141B2
Application number: JP2001016211A
Authority: JP
Inventors: 義斉森; 正幸佐藤; 正英松村
Original assignee: Toray Industries Inc
Current assignee: Toray Industries Inc
Priority date: 2001-01-24
Filing date: 2001-01-24
Publication date: 2011-06-29
Anticipated expiration: 2021-01-24
Also published as: JP2002220742A

Description

【０００１】
【発明の属する技術分野】
本発明は、高ストレッチ性を有し、織編物に使用したときにシボ・シワの無い優れた表面品位が得られるポリエステル系複合糸に関するものであり、詳しくは複合糸を構成する粘度の異なる２成分の内、少なくとも高粘度成分が繰り返し単位の８０モル％以上がトリメチレンテレフタレートである高ストレッチ織編物用ポリエステル系複合糸に関するものである。
【０００２】
【従来の技術】
従来、ポリエステルは機械的特性をはじめ、様々な優れた特性を有しているため、衣料用のみならず幅広く展開されている。また、近年のストレッチブームによりポリエステル糸にストレッチ性、捲縮性、嵩高性を与えるため種々の方法が採用されている。
【０００３】
例えば、ポリエステル糸に仮撚り加工を施し、加撚／解撚トルクを発現させてストレッチ性を付与する方法がある。しかしながら、このトルクは織物に使用した際には織物表面にシボを発生し、織物欠点となり易い問題がある。一方、収縮特性または溶融粘度の異なる重合体をサイドバイサイド型や偏芯芯鞘型に複合紡糸し、捲縮糸を得る技術も種々提案されている。例えば、特公昭４４−２５０４号公報や特開平４−３０８２７１号公報には固有粘度差或いは極限粘度差を有するポリエチレンテレフタレート（以下ＰＥＴと略す）のサイドバイサイド型複合糸、特開平５−２９５６３４号公報にはホモＰＥＴとそれより高収縮性の共重合ＰＥＴのサイドバイサイド型複合糸が記載されている。このような捲縮性ポリエステル複合糸を用いれば、確かにある程度のストレッチ性を得ることが出来るが、織物に使用した際のストレッチ性が不十分となり、満足なストレッチ性織物が得られにくいという問題があった。上記したようなサイドバイサイド型複合糸は織物拘束中での捲縮発現性能が低く、また捲縮がヘタリ易いためである。
【０００４】
また、特開平１１−１８９９２３号公報には、ＰＥＴとそれより溶融粘度の低いポリトリメチレンテレフタレート（以下ＰＴＴと略す）からなるポリエステル系複合糸が提案されている。しかし、ＰＴＴをＰＥＴより低粘度とすると、発現する捲縮形態の大部分について、捲縮コイル内側がＰＥＴ成分、外側がＰＴＴ成分となるために得られる捲縮糸のストレッチ性、捲縮発現性について十分満足のいくものではなく、またストレッチ性、捲縮発現性の保持性も非常に低いものとなり、実質的には固有粘度や極限粘度の異なるＰＥＴを用いたサイドバイサイド型複合により捲縮糸を得る公知の技術と何ら変わりのないものとなってしまうなどの問題がある。
【０００５】
【発明が解決しようとする課題】
本発明の目的は、前記のような従来技術の有する欠点・問題点を解消し、高ストレッチ性を有し、且つ織編物に使用したときにシボ・シワの無い優れた表面品位が得られる高ストレッチ織編物用ポリエステル系複合糸を提供することにある。
【０００６】
【課題を解決するための手段】
前記目的を達成するための本発明は、粘度の異なる２成分のポリエステルからなるサイドバイサイド型複合糸において、少なくとも高粘度成分が繰り返し単位の８０モル％以上がトリメチレンテレフタレートからなるポリトリメチレンテレフタレートであり、糸横断面の２成分の接合面と糸外周との２つの接点Ａ、Ｂを結んだ線分ＡＢの中心を通り、線分ＡＢと直交した直線Ｘと複合糸外周との２つの交点をＣ、Ｄとし、線分ＣＤの中心を通り線分ＣＤと直交した直線Ｙと糸外周との２つの交点をＥ、Ｆとしたとき、線分ＣＤと線分ＥＦの長さの比ＣＤ／ＥＦが下記（１）式を満足し、１．８×１０^-3ｃＮ／ｄｔｅｘ荷重下伸縮伸長率が４０％以上であることを特徴とする高ストレッチ織編物用ポリエステル系複合糸である。
【０００７】
１．２≦ＣＤ／ＥＦ≦４．０（１）
【０００８】
【発明の実施の形態】
以下、本発明を詳細に説明する。本発明において、複合糸を構成する２成分の重合体のうち、少なくとも高粘度成分は繰り返し単位の８０モル％以上がトリメチレンテレフタレートからなるポリトリメチレンテレフタレートである。ＰＴＴは、結晶構造においてアルキレングリコール部のメチレン鎖がゴーシュ−ゴーシュの構造（分子鎖が９０度に屈曲）であること、さらにはベンゼン環同士の相互作用（スタッキング、並列）による拘束点密度が低く、フレキシビリティーが高いことから、メチレン基の回転により分子鎖が容易に伸長・回復するという特有のストレッチ性を有している。このＰＴＴ固有のストレッチ性を複合糸においても十分発揮するためである。尚、本発明において、複合糸を構成する２成分の複合比率は通常サイドバイサイド型複合による伸縮性付与に用いられる複合比率であれば、特に規定するものではなく一般的には６５：３５〜３５：６５の範囲であり、好ましくは６０：４０〜４０：６０である。
【０００９】
また、本発明において、複合糸を構成する２成分の重合体のうち、低粘度成分はポリエチレンテレフタレートやポリブチレンテレフタレートなどを用いれば良く、また低粘度のポリトリメチレンテレフタレートを用いても良い。
【００１０】
図１は本発明の複合糸の一実施態様を示す糸横断面図である。図１において、２成分の接合面と複合糸外周との２つの接点Ａ、Ｂを結んだ線分ＡＢの中心を通り線分ＡＢと直交した直線Ｘと複合糸外周との２つの交点をＣ、Ｄとし、線分ＣＤの中心を通り線分ＣＤと直交した直線Ｙと複合糸外周との２つの交点をＥＦとしたとき、線分ＣＤと線分ＥＦの長さの比ＣＤ／ＥＦが前記（１）式のように１．２〜４．０とする。この比が１．２未満になると複合糸断面の２成分の接合面に対して、両ポリエステル成分が肉薄になり複合糸の捲縮発現性が低下し十分なストレッチ性能が得られないばかりでなく、織編物に使用し収縮処理により捲縮発現させた際に織編物表面にシボやシワが発生し表面品位の劣ったものになるばかりでなく、両ポリエステルの粘度差に起因したズリ速度差により、溶融紡糸時に吐出糸条の屈曲が大きくなり口金面に付着して糸切れを生じ、安定した紡糸が出来なくなるという問題が生じる。一方、この比が５．０を超えると、複合糸表面の反射光強度が強くなり、織編物表面でのイラツキ感が強く品位の劣ったものになるばかりでなく、溶融紡糸時や製織・編成加工時に通過するガイド類、例えば交絡付与ガイド、給油ガイド、糸道ガイドなどや編針での糸削れが発生し、製糸性、高次通過性の悪いものになるといった問題や、両ポリエステルの粘度差に起因したズリ速度差により、溶融紡糸時に吐出糸条が旋回してしまい糸長手方向の均一性が低下してしまうという問題が生じる。
線分ＣＤと線分ＥＦの長さの比ＣＤ／ＥＦは好ましくは、１．５〜２．０である。
【００１１】
本発明において、１．８×１０^-3ｃＮ／ｄｔｅｘ荷重下伸縮伸長率は、４０％以上である。１．８×１０^-3ｃＮ／ｄｔｅｘ荷重下伸縮伸長率が４０％を下回ると、織編物に使用した際のストレッチ性が乏しくなり、ストレッチ性織編物には適さない。１．８×１０^-3ｃＮ／ｄｔｅｘ荷重下伸縮伸長率は好ましくは５０％以上である。
【００１２】
本発明におけるサイドバイサイド型複合紡糸は、製造方法について特に限定するものではなく、通常の複合紡糸機を用いれば良く、複合紡糸した未延伸糸を一旦巻き取った後に、加熱延伸する方法を採用しても良く、複合紡糸した未延伸糸を一旦巻き取ることなく、加熱延伸する直接紡糸延伸法を採用しても良い。
【００１３】
【実施例】
以下、本発明を実施例によりさらに詳細に説明する。
【００１４】
本文および実施例中の固有粘度、１．８×１０^-3ｃＮ／ｄｔｅｘ荷重下伸縮伸長率、紡糸操業性、ストレッチ性、表面品位−１（シボ・シワ）、表面品位−２（イラツキ感）、総合評価は次の通りである。
【００１５】
Ａ．固有粘度：オルソクロロフェノール（以下ＯＣＰと略す）１０ｍｌ中に試料ポリマーを０．８ｇ溶かし、２５℃にてオストワルド粘度計を用いて相対粘度ηｒを次式により算出した値（ＩＶ）である。
ηｒ＝η／η₀＝（ｔ×ｑ）／（ｔ₀×ｑ₀）
ＩＶ＝０．０２４２ηｒ＋０．２６３４
但し、η：ポリマー溶液の粘度、η₀：ＯＣＰの粘度、ｔ：溶液の落下時間（秒）、ｑ：溶液の密度（ｇ／ｃｍ³）ｔ₀：ＯＣＰの落下時間（秒）、ｑ₀：ＯＣＰの密度（ｇ／ｃｍ³）。
【００１６】
Ｂ．１．８×１０^-3ｃＮ／ｄｔｅｘ荷重下伸縮伸長率：周長１ｍの手回し検尺器にて１０回巻のカセを作り、１．８×１０^-3ｃＮ／ｄｔｅｘの荷重を架けたカセを９０℃の熱水にて２０分間処理する。風乾し原長Ｌ１を測定した後、１．８×１０^-3ｃＮ／ｄｔｅｘの荷重を外し、８８．３×１０^-3ｃＮ／ｄｔｅｘの荷重を架けて２分後の長さＬ２を測定し、次式より求めた値（％）である。
伸縮伸長率＝｛（Ｌ２−Ｌ１）／Ｌ１｝×１００
Ｃ．紡糸操業性：２４錘で７２時間の紡糸を行った時の糸切れ回数で評価し、○および△を合格基準とした。
０回：○、１〜３回：△、４回以上
Ｄ．ストレッチ性：経糸に５６デシテックス１８フィラメントのＰＥＴ延伸糸を用い、緯糸に得られた複合糸を用いて平織り組織にて製織し、生機精練および９５℃×４０分間の熱水処理し、風乾して得た布帛について、２０人のパネラーによる官能評価を行った。比較例２に示した糸横断面が真円の糸を用いた織物に対して、緯方向に引っ張ったときに高いストレッチ性を有してると判断した人数で評価を行い、○および△を合格基準とした。
１８人以上：○、１４〜１７人：△、１３人以下：×
Ｅ．表面品位−１（シボ・シワ）：ストレッチ性の評価に用いる布帛と同様の製織、精練、熱水処理および風乾を行った幅５０ｃｍ×長さ２００ｃｍの布帛にあるシボ・シワの本数で以下の通り評価し、○および△を合格基準とした。
０〜１本：○、２〜４本：△、５本以上：×
Ｆ．表面品位−２（イラツキ感）：ストレッチ性の評価に用いる布帛について、２０人のパネラーによる官能評価を行った。市販の４０ワット蛍光灯下で布帛表面を観察し、表面にイラツキが無いと判断した人数で評価を行い、○および△を合格基準とした。
１８人以上：○、１４〜１７人：△、１３人以下：×
Ｇ．総合評価：前記した各評価項目を考慮して以下の通り総合的に評価し、○および△を合格基準とした。
全項目○判定：○、全項目△以上：○、×判定項目があるもの：×
実施例１
複合紡糸装置を用いて、固有粘度１．４７のＰＴＴと固有粘度０．５１のＰＥＴを各々溶融し、２４孔で幅０．１４ｍｍ×長さ１．０５ｍｍのスリット型吐出孔を有する同一紡糸口金から、糸横断面のＰＴＴとＰＥＴの容積比が１：１となるように吐出比を調整して、２７５℃の紡糸温度で紡出した。
次いで、紡出糸条を空気流で冷却固化した後、０．８重量％の油剤を付与し、一旦巻き取ることなく予熱温度６５℃、延伸倍率３．８倍で延伸し、１６０℃の熱セットを施して５６デシテックス２４フィラメントの複合糸を得た。
実施例１では、伸縮伸長率７８％であり、紡糸操業性は良好であった。また得られた糸を用いた布帛においては、非常に高いストレッチ性を有しており、表面にシボ・シワおよびイラツキ感が無く、非常に平滑で上品な表面品位を得た。結果をまとめて表１に示す。
【００１７】
実施例２および３
実施例２ではＣＤ／ＥＦ＝１．５となるように、また実施例３ではＣＤ／ＥＦ＝２．０となるように、それぞれ紡糸口金の吐出孔形状（スリット幅、スリット長）を変更し、実施例１と同様の方法で複合紡糸した。糸の伸縮伸長率はそれぞれ６７％、８９％であり、紡糸操業性は良好であった。また得られた糸を用いた布帛においては、高ストレッチ織物と言うに十分なストレッチ性を有しており、実施例２では表面にシボ・シワが１本見られたが品位としては十分であり、また実施例３では表面にシボ・シワおよびイラツキ感が無く非常に平滑で上品な表面品位を得た。
【００１８】
実施例４
ＣＤ／ＥＦ＝１．２となるように紡糸口金の吐出孔形状（スリット幅、スリット長）を変更し、実施例１と同様の方法で複合紡糸した。紡糸する際、糸曲がりが見られ、糸切れが２回発生したが、生産するには問題の無いレベルであった。尚、発生した糸切れは糸曲がりによる吐出孔周辺での汚れ発生によるものと思われる。糸の伸縮伸長率は４５％であり、この糸を用いた布帛においては、高ストレッチ織物と言うには問題の無いストレッチ性を有しており、表面にシボ・シワが４本見られたが、製品とするには問題の無いレベルであり、イラツキ感が無く良好な表面品位を得た。
【００１９】
実施例５
ＣＤ／ＥＦ＝４．０となるように紡糸口金の吐出孔形状（スリット幅、スリット長）を変更した事以外は、実施例１と同様の方法で複合紡糸した。紡出の際、紡糸糸条に糸道ガイドでの糸切れが３回発生したが、生産するに問題無いレベルであった。糸の伸縮伸長率は９２％であり、この糸を用いた布帛においては、非常に高いストレッチ性を有しており、表面にシボ・シワは無く、またイラツキ感はあるものの製品とするには問題の無いレベルであった。
【００２０】
比較例１
ＣＤ／ＥＦ＝６．０となるように紡糸口金の吐出孔形状（スリット幅、スリット長）を変更した事以外は、実施例１と同様の方法で複合紡糸した。紡出の際、紡糸糸条に著しい旋回挙動が見られ、また糸道規制ガイドや交絡ガイドでの毛羽発生による糸切れが多発し、複合糸を得ることが出来なかった。
【００２１】
比較例２
ＣＤ／ＥＦ＝１．０となるように紡糸口金の吐出孔形状を孔径０．５ｍｍの真円とし、実施例１と同様の方法で複合紡糸した。紡出の際、紡糸糸条に糸曲がりが発生し、紡糸後４８時間経過で、糸切れが発生したが、生産には問題の無いレベルであった。尚、この糸切れは著しい糸曲がりによる吐出孔周辺での汚れ発生によるものと思われる。糸の伸縮伸長率は３５％であり、布帛においてはストレッチ性を有していたが、布帛表面のイラツキ感は無いものの、多数のシボ・シワが見られ良好な品位の製品とは言えないものとなった。
【００２２】
比較例３
ＣＤ／ＥＦ＝０．６となるように紡糸口金の吐出孔形状（スリット幅、スリット長）を変更し、実施例１と同様の方法で複合紡糸した。紡出の際、紡糸糸条に著しい糸曲がりと旋回挙動が見られ、糸切れが多発した。糸の伸縮伸長率は２３％であり、布帛においては、高ストレッチ織物と言えないストレッチ性となり、また、布帛表面のシボ・シワは無いもののイラツキ感が非常に強く、良好な品位の高ストレッチ織物とは言えないものとなった。また、紡糸の際、延伸倍率を上げて伸縮伸長率を高くしようと試みたが、延伸過程での糸切れが増加する一方であり、延伸倍率によるストレッチ性能の向上は不可能であった。
【００２３】
比較例４
糸の伸縮伸長率を１０％とするように、延伸倍率を低倍率化したこと以外は、実施例１と同一の方法で複合糸を得た。紡糸操業性は良好であったが、得られた糸を用いた布帛においては、表面品位は良好であるものの、ストレッチ性が低く、高ストレッチ織物とは言えないものとなった。
【００２４】
【表１】

【００２５】
【発明の効果】
上述したように、本発明によれば、サイドバイサイド型複合糸を構成する高粘度成分にＰＴＴを用い、糸横断面の形状と１．８×１０^-3ｃＮ／ｄｔｅｘ荷重下伸縮伸長率を適正なものとすることにより、平滑で上品な品位と高いストレッチ性を有する高ストレッチ織編物用ポリエステル系複合糸を得ることができる。
【図面の簡単な説明】
【図１】本発明の一実施様態を示す糸横断面図
【図２】本発明の他の実施様態を示す糸横断面図
【符号の説明】
Ａ：糸横断面の２成分の接合面と糸外周との接点
Ｂ：糸横断面の２成分の接合面と糸外周とのもう一方の接点
Ｘ：線分ＡＢの中心を通り、線分ＡＢと直交した直線
Ｃ：直線Ｘと糸外周との交点
Ｄ：直線Ｘと糸外周との交点
Ｙ：線分ＣＤの中心を通り、線分ＣＤと直交した直線
Ｅ：直線Ｙと糸外周との交点
Ｆ：直線Ｙと糸外周との交点[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a polyester-based composite yarn having high stretch properties and having excellent surface quality without wrinkles or wrinkles when used in a woven or knitted fabric. Among the components, at least a high-viscosity component relates to a polyester composite yarn for high-stretch woven and knitted fabric in which 80 mol% or more of the repeating unit is trimethylene terephthalate.
[0002]
[Prior art]
Conventionally, since polyester has various excellent properties including mechanical properties, it has been widely deployed not only for clothing. In addition, various methods have been adopted in order to give stretchability, crimpability, and bulkiness to polyester yarns by recent stretch booms.
[0003]
For example, there is a method of imparting stretch properties by applying false twisting to a polyester yarn to express twisting / untwisting torque. However, when this torque is used for a woven fabric, there is a problem that the surface of the woven fabric is creased to easily cause a fabric defect. On the other hand, various techniques for obtaining crimped yarns by composite spinning of polymers having different shrinkage characteristics or melt viscosities into side-by-side types or eccentric core-sheath types have been proposed. For example, Japanese Patent Publication No. 44-2504 and Japanese Patent Application Laid-Open No. 4-308271 disclose a side-by-side type composite yarn of polyethylene terephthalate (hereinafter abbreviated as PET) having an intrinsic viscosity difference or an intrinsic viscosity difference, and Japanese Patent Application Laid-Open No. 5-295634. Describes a side-by-side type composite yarn of homo-PET and copolymer PET having a higher shrinkage than that. If such a crimped polyester composite yarn is used, it is possible to obtain a certain degree of stretchability, but the stretchability when used in the fabric is insufficient, and it is difficult to obtain a satisfactory stretch fabric. was there. This is because the side-by-side type composite yarn as described above has a low crimping performance in restraining the fabric and is easy to crimp.
[0004]
Japanese Patent Application Laid-Open No. 11-189923 proposes a polyester composite yarn comprising PET and polytrimethylene terephthalate (hereinafter abbreviated as PTT) having a lower melt viscosity. However, if the viscosity of PTT is lower than that of PET, for the majority of the crimped forms that appear, the crimped coil has a PET component on the inner side and a PTT component on the inner side of the crimped coil. In addition, the stretchability and the crimp-retaining property are very low, and the crimped yarn is substantially made by side-by-side type composite using PET with different intrinsic viscosity and intrinsic viscosity. There is a problem that it becomes no different from the known technique to be obtained.
[0005]
[Problems to be solved by the invention]
The object of the present invention is to eliminate the disadvantages and problems of the prior art as described above, to have high stretch properties, and to obtain excellent surface quality free from wrinkles and wrinkles when used for woven or knitted fabrics. An object of the present invention is to provide a polyester composite yarn for stretch knitted fabric.
[0006]
[Means for Solving the Problems]
The present invention for achieving the above object is a polytrimethylene terephthalate in which at least a high-viscosity component is composed of trimethylene terephthalate at least 80 mol% of repeating units in a side-by-side type composite yarn composed of two-component polyesters having different viscosities. The two intersections of the straight line X passing through the center of the line segment AB connecting the two contact points A and B of the two-component joint surface of the yarn cross section and the yarn outer periphery and perpendicular to the line segment AB and the outer periphery of the composite yarn C and D, where E and F are the two intersection points of the straight line Y passing through the center of the line segment CD and orthogonal to the line segment CD and the outer periphery of the yarn, the ratio CD / of the length of the line segment CD and the line segment EF EF satisfies the following formula (1), and is a polyester-based composite yarn for high-stretch woven and knitted fabrics, characterized in that the stretch / elongation rate under load of 1.8 × 10 ⁻³ cN / dtex is 40% or more.
[0007]
1.2 ≦ CD / EF ≦ 4.0 (1)
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail. In the present invention, among the two-component polymers constituting the composite yarn, at least the high-viscosity component is polytrimethylene terephthalate in which 80 mol% or more of the repeating units are composed of trimethylene terephthalate. In PTT, the methylene chain of the alkylene glycol part in the crystal structure is a Gauche-Gauche structure (the molecular chain is bent at 90 degrees), and further, the density of restraint points due to the interaction between benzene rings (stacking, parallel) is low. Because of its high flexibility, it has a unique stretch property that the molecular chain can be easily extended and recovered by the rotation of the methylene group. This is because the stretch property peculiar to PTT is sufficiently exhibited even in the composite yarn. In the present invention, the composite ratio of the two components constituting the composite yarn is not particularly specified as long as it is a composite ratio that is usually used for imparting stretchability by side-by-side composite, and is generally 65:35 to 35: It is the range of 65, Preferably it is 60: 40-40: 60.
[0009]
In the present invention, among the two-component polymers constituting the composite yarn, the low-viscosity component may be polyethylene terephthalate, polybutylene terephthalate, or the like, or low-viscosity polytrimethylene terephthalate.
[0010]
FIG. 1 is a cross-sectional view of a yarn showing an embodiment of the composite yarn of the present invention. In FIG. 1, the two intersections of the straight line X passing through the center of the line segment AB connecting the two contact points A and B between the two-component joint surface and the composite thread outer periphery and perpendicular to the line segment AB and the outer periphery of the composite thread C , D, where EF is the intersection of the straight line Y passing through the center of the line segment CD and perpendicular to the line segment CD and the outer periphery of the composite yarn, the ratio CD / EF of the length of the line segment CD to the line segment EF is It is set to 1.2-4.0 like the said (1) Formula. When this ratio is less than 1.2, not only the polyester component is thinned against the two-component joint surface of the composite yarn cross section, but the crimp expression of the composite yarn is reduced and sufficient stretch performance cannot be obtained. When used in woven or knitted fabrics, when crimped by shrinkage treatment, wrinkles and wrinkles occur on the surface of the woven or knitted fabric, resulting in inferior surface quality. When the melt spinning is performed, the discharge yarn bends more and adheres to the base surface, resulting in a yarn breakage. This causes a problem that stable spinning cannot be performed. On the other hand, when this ratio exceeds 5.0, the reflected light intensity on the surface of the composite yarn becomes strong and the irritating feeling on the surface of the knitted and knitted fabric becomes strong and inferior in quality, but also at the time of melt spinning and weaving / knitting. Guides that pass during processing, such as entanglement guides, oiling guides, yarn path guides, and thread cutting with knitting needles, resulting in poor yarn production and high-order passage, and the viscosity difference between both polyesters Due to the difference in shear rate due to the above, there arises a problem that the discharge yarn is swirled during melt spinning and the uniformity in the longitudinal direction of the yarn is lowered.
The length ratio CD / EF of the line segment CD and the line segment EF is preferably 1.5 to 2.0.
[0011]
In the present invention, the expansion / contraction elongation ratio under load of 1.8 × 10 ⁻³ cN / dtex is 40% or more. If the stretch / elongation ratio under load of 1.8 × 10 ⁻³ cN / dtex is less than 40%, the stretchability when used in a woven or knitted fabric becomes poor and is not suitable for a stretchable woven or knitted fabric. The expansion / contraction elongation rate under a load of 1.8 × 10 ⁻³ cN / dtex is preferably 50% or more.
[0012]
The side-by-side type composite spinning in the present invention is not particularly limited with respect to the production method, and an ordinary composite spinning machine may be used, and a method in which the composite-spun undrawn yarn is once wound and then heated and drawn is adopted. It is also possible to employ a direct spinning and stretching method in which the composite-spun undrawn yarn is stretched by heating without winding it once.
[0013]
【Example】
Hereinafter, the present invention will be described in more detail with reference to examples.
[0014]
Intrinsic viscosity in the text and examples, 1.8 × 10 ⁻³ cN / dtex, stretch / elongation ratio under load, spinning operability, stretchability, surface quality-1 (wrinkles / wrinkles), surface quality-2 (irritation) The overall evaluation is as follows.
[0015]
A. Intrinsic viscosity: A value (IV) obtained by dissolving 0.8 g of a sample polymer in 10 ml of orthochlorophenol (hereinafter abbreviated as OCP), and calculating the relative viscosity ηr by the following equation using an Ostwald viscometer at 25 ° C.
ηr = η / η ₀ = (t × q) / (t ₀ × q ₀ )
IV = 0.0242ηr + 0.2634
Where η: viscosity of the polymer solution, η ₀ : OCP viscosity, t: solution drop time (seconds), q: solution density (g / cm ³ ) t ₀ : OCP drop time (seconds), q ₀ : OCP density (g / cm ³ ).
[0016]
B. Expansion and contraction rate under 1.8 x 10 ^-3 cN / dtex load: A casserole with 10 turns using a hand-held measuring instrument with a circumference of 1 m and a load of 1.8 x 10 ^-3 cN / dtex is applied. Is treated with hot water at 90 ° C. for 20 minutes. After air-drying and measuring the original length L1, the load of 1.8 × 10 ⁻³ cN / dtex is removed, and the load L of 88.3 × 10 ⁻³ cN / dtex is applied to measure the length L2 after 2 minutes. The value (%) obtained from the following equation.
Expansion / contraction elongation = {(L2-L1) / L1} × 100
C. Spinning operability: Evaluated based on the number of yarn breaks when spinning for 24 hours with 24 spindles, and ○ and Δ were acceptable standards.
0 times: ○, 1-3 times: Δ, 4 times or more Stretching property: 56-decitex 18-filament PET drawn yarn is used as the warp, weaved in a plain weave structure using the composite yarn obtained as the weft, scoured with raw machinery and treated with hot water at 95 ° C for 40 minutes, then air-dried. The obtained fabric was subjected to sensory evaluation by 20 panelists. Evaluation was performed with the number of persons judged to have high stretchability when pulled in the weft direction with respect to the woven fabric using a thread whose cross section was a perfect circle shown in Comparative Example 2, and passed ◯ and △. Standard.
18 or more: ○, 14-17: △, 13 or less: ×
E. Surface quality-1 (wrinkles / wrinkles): The number of wrinkles / wrinkles in a fabric 50 cm wide × 200 cm long subjected to weaving, scouring, hot water treatment and air drying similar to the fabric used for the evaluation of stretchability. The evaluation was as follows, and ○ and Δ were accepted criteria.
0-1: ○, 2-4: Δ, 5 or more: ×
F. Surface quality-2 (feeling of irritation): The fabric used for evaluation of stretchability was subjected to sensory evaluation by 20 panelists. The surface of the fabric was observed under a commercially available 40-watt fluorescent lamp, and the evaluation was performed with the number of people judged that there was no irritation on the surface.
18 or more: ○, 14-17: △, 13 or less: ×
G. Comprehensive evaluation: Considering each evaluation item mentioned above, it evaluated comprehensively as follows and made (circle) and (triangle | delta) the acceptance criteria.
All items ○ Judgment: ○, all items △ or more: ○, × Items with judgment items: ×
Example 1
Using a composite spinning device, PTT having an intrinsic viscosity of 1.47 and PET having an intrinsic viscosity of 0.51 are respectively melted, and the same spinneret having 24 holes of 0.14 mm wide × 1.05 mm long slit-type discharge holes Then, the discharge ratio was adjusted so that the volume ratio of PTT and PET in the yarn cross section was 1: 1, and spinning was performed at a spinning temperature of 275 ° C.
Next, after spinning and solidifying the spun yarn with an air stream, 0.8% by weight of an oil agent is applied, and the yarn is stretched at a preheating temperature of 65 ° C. and a draw ratio of 3.8 times without being wound once. A set was made to obtain a composite yarn of 56 dtex 24 filaments.
In Example 1, the stretch / elongation rate was 78%, and the spinning operability was good. In addition, the fabric using the obtained yarn had a very high stretch property, and there was no wrinkle / wrinkle or irritation on the surface, and a very smooth and elegant surface quality was obtained. The results are summarized in Table 1.
[0017]
Examples 2 and 3
The ejection hole shape (slit width and slit length) of the spinneret was changed so that CD / EF = 1.5 in Example 2 and CD / EF = 2.0 in Example 3. Composite spinning was performed in the same manner as in Example 1. The stretch / elongation rates of the yarns were 67% and 89%, respectively, and the spinning operability was good. Moreover, the fabric using the obtained yarn has sufficient stretchability to be a high stretch fabric, and in Example 2, one wrinkle / wrinkle was seen on the surface, but the quality was sufficient. In Example 3, the surface was free of wrinkles, wrinkles and irritations, and a very smooth and elegant surface quality was obtained.
[0018]
Example 4
The spinneret discharge hole shape (slit width, slit length) was changed so that CD / EF = 1.2, and composite spinning was performed in the same manner as in Example 1. When spinning, the yarn was bent and the yarn breakage occurred twice. The generated thread breakage is considered to be due to the occurrence of contamination around the discharge hole due to the yarn bending. The stretch / elongation rate of the yarn is 45%, and the fabric using this yarn has a stretch property that is not a problem as a high stretch fabric, and four wrinkles and wrinkles were observed on the surface. The product is at a level that does not cause any problems, and has a good surface quality with no irritation.
[0019]
Example 5
Composite spinning was performed in the same manner as in Example 1 except that the discharge hole shape (slit width, slit length) of the spinneret was changed so that CD / EF = 4.0. During spinning, yarn breakage occurred at the yarn guide three times on the spun yarn, but it was at a level that was not problematic for production. The stretch / elongation rate of the yarn is 92%, and the fabric using this yarn has a very high stretch property, has no wrinkles / wrinkles on the surface, and has a feeling of irritation. There was no problem.
[0020]
Comparative Example 1
Composite spinning was performed in the same manner as in Example 1, except that the discharge hole shape (slit width, slit length) of the spinneret was changed so that CD / EF = 6.0. At the time of spinning, a remarkable swirling behavior was observed in the spun yarn, and yarn breakage occurred frequently due to the occurrence of fuzz in the yarn path regulation guide and the entanglement guide, making it impossible to obtain a composite yarn.
[0021]
Comparative Example 2
The spinneret discharge hole shape was a perfect circle having a hole diameter of 0.5 mm so that CD / EF = 1.0, and composite spinning was performed in the same manner as in Example 1. During spinning, the spun yarn was bent, and yarn breakage occurred 48 hours after spinning, but it was at a level with no problem in production. This thread breakage is considered to be caused by the occurrence of contamination around the discharge hole due to a significant yarn bending. The stretch / elongation rate of the yarn was 35% and the fabric had stretch properties, but there was no feeling of irritation on the fabric surface, but many wrinkles and wrinkles were seen and it could not be said to be a product of good quality It became.
[0022]
Comparative Example 3
The spinneret discharge hole shape (slit width, slit length) was changed so that CD / EF = 0.6, and composite spinning was performed in the same manner as in Example 1. At the time of spinning, remarkable yarn bending and swirling behavior were observed on the spun yarn, and yarn breakage occurred frequently. The stretch / elongation rate of the yarn is 23%, and in the fabric, it becomes a stretch property that cannot be said to be a high stretch fabric, and there is no wrinkles or wrinkles on the surface of the fabric, but the feeling of irritation is very strong, and the high stretch fabric of good quality. It could not be said. Also, while spinning, an attempt was made to increase the stretch ratio to increase the stretch / elongation rate, but the thread breakage during the stretching process was increasing, and it was impossible to improve the stretch performance by the stretch ratio.
[0023]
Comparative Example 4
A composite yarn was obtained in the same manner as in Example 1 except that the draw ratio was lowered so that the expansion / contraction elongation rate of the yarn was 10%. Although the spinning operability was good, the fabric using the obtained yarn had good surface quality but low stretchability and could not be said to be a high stretch fabric.
[0024]
[Table 1]

[0025]
【The invention's effect】
As described above, according to the present invention, PTT is used as the high-viscosity component constituting the side-by-side type composite yarn, and the shape of the cross section of the yarn and the expansion / contraction elongation rate under the load of 1.8 × 10 ⁻³ cN / dtex are appropriate. As a result, it is possible to obtain a polyester-based composite yarn for high stretch woven and knitted fabric having smooth and elegant quality and high stretchability.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a yarn showing one embodiment of the present invention. FIG. 2 is a cross-sectional view of a yarn showing another embodiment of the present invention.
A: Contact point between the two-component joining surface of the yarn cross section and the outer periphery of the yarn B: Another contact point between the two-component joining surface of the yarn cross-sectional surface and the outer periphery of the yarn X: The line segment AB passes through the center of the line segment AB. A straight line C orthogonal to the line X and an intersection point D between the straight line X and the thread outer periphery D: an intersection point Y between the straight line X and the thread outer periphery Y: a straight line E passing through the center of the line segment CD and perpendicular to the line segment CD: Intersection point F: Intersection point between straight line Y and thread circumference

Claims

In a side-by-side type composite yarn composed of two-component polyesters having different viscosities, at least the high-viscosity component is polytrimethylene terephthalate in which 80% by mole or more of the repeating units are composed of trimethylene terephthalate, C and D are the two intersections of the straight line X passing through the center of the line segment AB connecting the two contact points A and B with the yarn outer periphery and orthogonal to the line segment AB and the outer periphery of the composite yarn, and the center of the line segment CD is When the two intersections of the straight line Y perpendicular to the line segment CD and the outer periphery of the yarn are E and F, the ratio CD / EF of the length of the line segment CD to the line segment EF satisfies the following equation (1), A polyester-based composite yarn for high-stretch woven and knitted fabrics, wherein the stretch / elongation rate under a load of 1.8 × 10 ⁻³ cN / dtex is 40% or more.
1.2 ≦ CD / EF ≦ 4.0 (1)