JP3937919B2 - Method for spinning polytrimethylene terephthalate fiber - Google Patents

Description

【０００７】
【発明の実施の形態】
本発明における紡糸温度Ｘ（℃）は、２５５〜２８０℃の範囲である。紡糸温度が２５５℃を下回る場合、発現される強度が低くなる傾向があるばかりでなく、ＰＴＴポリマの流動性が著しく低下し、安定した紡糸が行えない。また、紡糸温度が２８０℃を超える場合、紡糸口金におけるＰＴＴポリマ流動性が過剰に高くなり、複数の吐出孔におけるポリマ計量性が著しく低下し、単糸均一性が劣るものとなるばかりでなく、長期連続紡糸における吐出孔汚れが発生しやすい。
【０００８】
本発明におけるＰＴＴポリマ滞留時間Ｙ（分）は、設定した紡糸温度Ｘ（℃）に対して、１８１．８−０．６３９Ｘ以上である必要がある。これを下回る場合、
ポリマ流動性が著しく低下し、安定した紡糸が困難となるばかりでなく、紡糸パック内部のポリマ濾過部圧力が上昇し、ポリマが洩れやすくなり長期間連続紡糸することが出来ない。また、ＰＴＴポリマ滞留時間Ｙ（分）は、設定した紡糸温度Ｘ（℃）に対して、２３０．３−０．７９１Ｘ以下である必要がある。これを上回るとＰＴＴポリマが熱劣化し、紡糸糸切れや以降の工程における毛羽発生を誘発する。すなわち、本発明におけるＰＴＴポリマ滞留時間Ｙと紡糸温度Ｘの関係は、図１に示した斜線部分の範囲である。
【０００９】
なお、本発明における紡糸温度Ｘ（℃）とは、図２に示す通り、押し出し機２から出る包埋保温されたポリマー配管に取り付けられた紡糸温度検出器４により検出した温度を示し、ＰＴＴポリマ滞留時間Ｙ（分）は、押し出し機出口からポリマー押し出を開始した際、該出口に設置した押し出し機先端圧力検出器３により検出した圧力が０．９ＭＰａを示した時点からポリマー配管を通過して紡糸口金７から吐出するまでに要した時間を示す。
【００１０】
本発明において、フェニル基を含有せず、加熱減量率が５０％以下であるシリコーン系離型剤を紡糸口金面に塗布することが必要である。フェニル基を含有しないシリコーン系離型剤は、ポリマ離型性が良好であり、口金面汚れの堆積を抑制することができ、さらに加熱減量率が５０％以下であるものを使用することにより、ワイピング周期を４０時間以上に延長し生産効率を向上する効果がある。より好ましくは、加熱減量率が４０％以下である。また、シリコーン系離型剤の溶液粘度は２０〜６０ｐｏｉｓｅであることが好ましく、溶液粘度が２０ｐｏｉｓｅを下回ると、口金面に塗布した際に斑が生じやすく、離型剤の効果が不均一なものとなり、また溶液粘度が６０ｐｏｉｓｅを上回ると、粘度が高くなり過ぎるために、かえって口金面汚れが発生しやすくなる。なお、シリコーン系離型剤における加熱減量率とは、シリコーン系離型剤をステンレス製φ７０ｍｍシャーレに約１．５ｇ採取した後、電子天秤にて重量測定し、２８５℃の高温槽に保管して１６８時間経過後に、再度重量を測定した際の重量減少分を加熱前重量で除した値（％）である。例えば、加熱前重量１．５ｇ、１６８時間加熱後の重量が１．２ｇであれば、加熱減量率は（１．２−１．５）÷１．５×１００＝２０％となる。また、シリコーン系離型剤における溶液粘度は、Ｂ型粘度計を用いて室温にて測定を行った値（ｐｏｉｓｅ）である。
【００１１】
本発明に用いるポリトリメチレンテレフタレートには、必要に応じて本発明の効果を損なわない範囲で、イソフタル酸、２−２ビス｛４−（β−ヒドロキシ）フェニル｝プロパン等の共重合成分や、酸化チタン等の艶消し剤、ヒンダートフェノール系化合物等の酸化防止剤、顔料、難撚剤、抗菌剤、消臭剤、導電性付与剤等が配合されていても良い。なお、本発明の紡糸にあたっては、ポリトリメチレンテレフタレートは、押し出し機やポリマ配管における加水分解を防止するために、一旦ペレット状に加工したものを水分率１００ｐｐｍ以下に乾燥させて実施することが好ましい。より好ましくは水分率５０ｐｐｍ以下である。
【００１２】
本発明において、紡糸口金から吐出した糸条の引き取り方法については、特に限定するものではなく、特開平１１−１７２５２６号公報で提案されている方法、すなわち紡糸口金より押し出しした溶融マルチフィラメントを口金直下に設けた３０〜２００℃の雰囲気温度を保持した長さ２〜８０ｃｍの保温領域を通過させて、急激な冷却を抑制した後に、急冷して固体マルチフィラメントとして４０〜７０℃の第１ロールにて３００〜４０００ｍ／ｍｉｎで巻き付け、次に１２０〜１６０℃の第２ロールに巻き付け、第１ロールと第２ロールの間で１．５〜３．０倍に延伸して第２ロールより低速で巻き取る方法、或いは、特開２０００−７３２３０号公報で提案されている方法、すなわち紡糸した糸条を一旦冷却固化した後、内部雰囲気温度が１２０〜２２０℃の筒状加熱装置を通過させて熱処理し、再び冷却した後、３０００ｍ／分以上の引取速度で糸条を引き取り、弛緩率４〜１２％で弛緩熱処理を施し巻き取る方法など、いずれの方法を採用しても良い。
【００１３】
【実施例】
以下、実施例により本発明を更に詳細に説明する。なお、本発明の実施例中の主な測定方法は以下の通りである。
【００１４】
１．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。
【００１５】
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】
２．ワイピング周期
各実施例の紡糸条件にて、８糸条同時紡糸で５回紡糸を行い、糸切れが発生するまでの時間の平均値をワイピング周期とした。
【００１７】
３．糸品位
図３に示す東レ社製フライカウンターを用い、得られたマルチフィラメントのパッケージ８個について、５５０ｍ／分の速度で解舒しながら、糸長３００００ｍについて、毛羽個数を測定した値（個／万ｍ）で以下の通り評価した。
【００１８】
○：毛羽個数が０．５個／万ｍ未満
△：毛羽個数が０．６〜１個／万ｍ
×：毛羽個数が１〜５個／万ｍを超える。
【００１９】
実施例１
水分率４８ｐｐｍまで乾燥した固有粘度１．４７のＰＴＴポリマを紡糸温度２５５℃にて、孔直径０．２４ｍｍ、孔深度０．４ｍｍの３６ホールが同心円状に配列してある紡糸口金を用いて、吐出量２５．５４ｇ／分で押し出し、風速４０ｍ／分、温度２０℃の冷却風にて一旦冷却した後に、内部雰囲気温度１８０℃、長さ１ｍの筒状加熱装置にて糸条を加熱し、再度冷却後、該筒状加熱装置より下方４０ｃｍの位置にある給油ガイドにて糸条に仕上げ剤を０．８％付与し、更に下方３０ｃｍの位置にある交絡ノズルにて交絡付与した後に、室温の第１ロールにて２６２０ｍ／分の速度で引き取り、引き続いて室温の第２ロールとの間で４．０％のリラックスを付与した後に巻取機にて糸条を巻き取り、９７デシテックス３６フィラメントの未延伸糸を得た。この際、押し出し機は市販の一軸押し出し機を用い、ポリマ滞留時間が２８分となる様にポリマ配管およびパック内濾過部分の容積を調整した。また、紡糸口金には、加熱減量率４６％、溶液粘度４２ｐｏｉｓｅのジメチルシリコーン系離型剤を塗布して、紡糸を開始した。この時のワイピング周期は５３時間と安定した紡糸性を示し、得られた糸は、強度３．０ｃＮ／ｄｔｅｘ、伸度９０％であり、仮撚加工や混繊複合加工などに実際使用可能なレベルの品位を有しているものとなった。結果をまとめて表１に示す。
【００２０】
実施例２〜９、比較例２〜７
離型剤の種類、紡糸温度、ポリマ滞留時間を変えた以外は、実施例１と同様の方法で紡糸を行った。なお、ポリマ滞留時間は、ポリマ配管およびパック内濾過部容積を変更して調整した。また、実施例５、６では、加熱減量率２８％で溶液粘度２１ｐｏｉｓｅのジメチルシリコーン系離型剤を使用し、実施例８、９では加熱減量率３４％で溶液粘度３１ｐｏｉｓｅのジメチルシリコーン系離型剤を使用した。比較例においては、実施例にてワイピング周期が最も長く良好であった加熱減量率２８％で溶液粘度２１ｐｏｉｓｅのジメチルシリコーン系離型剤を使用することとした。本発明の範囲の紡糸条件では、全ての実施例においてワイピング周期が４０時間以上となり、得られた糸の品位も仮撚加工や混繊複合加工などの加工糸用途に使用可能な良好なものであった。一方、本発明の範囲から外れた紡糸条件では、ワイピング周期が実際生産するには不十分なものとなるばかりでなく、得られた糸の毛羽数も多く、また、紡糸機に設けてある糸道規制ガイドや交絡ガイドなどに単糸が切れて付着した毛羽や、糸表面が削れて蓄積したスカムが発生するなどの問題が発生した。結果をまとめて表１に示す。
【００２１】
比較例１
比較例１では、紡糸温度２５０℃でポリマ滞留時間が２５分となるようにポリマ配管およびパック内濾過部容積を調整して、加熱減量率２８％で溶液粘度２１ｐｏｉｓｅのジメチルシリコーン系離型剤を塗布し、実施例１と同様の方法で紡糸したが、糸切れ多発しワイピング周期は４時間となった。また、ＰＴＴポリマがポリマ配管内での十分な流動性を保持出来なかったためと思われる紡糸口金での吐出斑や単糸繊度バラツキが発生した。
【００２２】
比較例８
ポリマ滞留時間が０．５分となる様に、ポリマ配管およびパック内濾過部容積を調整して、加熱減量率２８％で溶液粘度２１ｐｏｉｓｅのジメチルシリコーン系離型剤を塗布し、実施例１と同様の方法でＰＴＴポリマを紡糸しようとしたが、押し出し機からのＰＴＴポリマ押し出し斑が発生し、またポリマ配管と紡糸パックポリマ流入部との連結部およびパック内でのＰＴＴポリマの洩れが発生し、実際に紡糸することが不可能となった。これはポリマ配管やパック内濾過部通過時の圧力損失が過大となったためと思われる。
【００２３】
【表１】

Ｘ＝２５５、Ｙ＝１８．８５５〜２８．５９
Ｘ＝２６０、Ｙ＝１５．６６ 〜２４．６４
Ｘ＝２６５、Ｙ＝１２．４６５〜２０．６８５
Ｘ＝２７０、Ｙ＝ ９．２７ 〜１６．７３
Ｘ＝２８０、Ｙ＝ ２．８８ 〜 ８．８２
【００２４】
【発明の効果】
上述したように、本発明によれば、ＰＴＴポリマを紡糸するに際し、紡糸温度とポリマ滞留時間を適正な範囲とし、特定のシリコーン系離型剤を紡糸口金面に塗布することで、長時間紡糸しても口金吐出孔周辺の汚れが少なく、糸切れや糸斑、さらには毛羽の発生を抑制し、従来行われているポリトリメチレンテレフタレート紡糸方法の欠点を改良し、ワイピング周期を４０時間以上として安定した連続紡糸性と仮撚加工や混繊複合加工などに適した品位を有する糸を得ることができる。
【図面の簡単な説明】
【図１】本発明の範囲を示す説明図
【図２】本発明を実施する紡糸機の概略を示す模式図
【図３】本発明の実施例に用いる毛羽測定機の概略を示す模式図
【符号の説明】
１：ＰＴＴ乾チップホッパー
２：一軸押し出し機
３：押し出し機先端圧力検出器
４：紡糸温度検出器
５：紡糸保温ボックス
６：紡糸パック濾過部
７：紡糸口金
８：糸条
９：チムニー糸条冷却装置
１０：筒状加熱装置
１１：給油ガイド
１２：交絡ノズル
１３：第１ロール
１４：第２ロール
１５：パッケージ
１６：パッケージ
１７：毛羽検知器
１８：解舒装置
１９：糸条吸引装置
２０：フライカウンター本体[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for spinning polytrimethylene terephthalate fiber, and more specifically, a specific silicone-based mold release agent having a spinning temperature and a polymer residence time when spinning polytrimethylene terephthalate fiber within an appropriate range. Is applied to the spinneret surface, so that even when spinning for a long time, there is little dirt around the nozzle discharge hole, and the conventional polytrimethylene terephthalate (hereinafter referred to as PTT) is suppressed by suppressing the occurrence of yarn breakage, yarn unevenness, and fluff. The present invention relates to a spinning method of polytrimethylene terephthalate fiber that improves the shortcomings of the spinning method, and can obtain stable continuous spinning properties and quality suitable for false twisting and mixed fiber composite processing .
[0002]
[Prior art]
Various proposals have been made for methods of spinning PTT fibers. For example, in Japanese Patent Application Laid-Open No. 11-200133, a spinneret surface temperature is 230 to 280 ° C., a silicone mold release agent containing methylphenylsilicone and dimethylsilicone and having a viscosity of 2000 to 8000 cpoise is used. A spinning method for PTT fibers applied to the base has been proposed. However, simply setting the spinneret surface temperature to 230 to 280 ° C. can suppress thermal degradation until the PTT polymer is melted and discharged from the die. Therefore, the yarn breakage and fluff generation cannot be suppressed by any method after the discharge, even if the drawing, stretching and winding are performed. In general, in the melt spinning method of polyester, with the passage of time from the start of spinning, a part of the discharged polymer remains on the die surface and thermally deteriorated or gelled, and the die discharge hole is deposited. The surrounding stains increase, the yarn is bent and picked, and thread breakage, yarn unevenness, and fluffing are induced. To suppress this phenomenon, a silicone mold release agent is usually applied to the die surface. When the die surface becomes extremely dirty, a wiping operation is performed to clean the die surface and renew the release agent. Although the heat resistance is relatively good, silicone containing a phenyl group has poor polymer releasability, and it is impossible to maintain a wiping cycle of a level that can actually be produced, that is, 40 hours or more, thus improving production efficiency. Difficult to do.
[0003]
Other methods for spinning PTT fibers have been proposed in JP-A-52-5320, JP-A-52-8124, WO99 / 27168, and the like. In any of these methods, a PTT polymer is melted. There is no description of how to prevent thermal degradation of the PTT polymer from the time it is discharged from the spinneret, and there is insufficient suppression of fluff and yarn breakage, which does not lead to stable production. there were.
[0004]
[Problems to be solved by the invention]
The object of the present invention is to solve the above-mentioned problems and sufficiently suppress the shrinkage after winding of the PTT yarn, and without causing fuzz and yarn breakage, sufficient stable production is possible even during long-term continuous spinning. Another object of the present invention is to provide a method for spinning PTT fibers.
[0005]
[Means for Solving the Problems]
As a result of the sharp pursuit by the present inventors, in order to drastically solve fluff and yarn breakage and perform efficient production, the heat of the PTT polymer in the melt discharge process from melting the polymer to discharging from the spinneret It has been found that it is important to sufficiently suppress deterioration. That is, the present invention for achieving the above object, 80 polyester spinning yarn temperature X (° C.) the polytrimethylene terephthalate composed mol% or more from trimethylene terephthalate repeating units, the polymer residence time in the spinning machine Y (Min), and when satisfying the following formulas (1) and (2) and spinning at the same time , a silicone-based release having no phenyl group, a heating loss ratio of 50% or less, and a solution viscosity of 20 to 60 poise. A method of spinning polytrimethylene terephthalate fiber, wherein a mold agent is applied to a spinneret surface .
[0006]

[0007]
DETAILED DESCRIPTION OF THE INVENTION
The spinning temperature X (° C.) in the present invention is in the range of 255 to 280 ° C. When the spinning temperature is lower than 255 ° C., not only the developed strength tends to be lowered, but also the fluidity of the PTT polymer is remarkably lowered, and stable spinning cannot be performed. Further, when the spinning temperature exceeds 280 ° C., not only the PTT polymer fluidity in the spinneret becomes excessively high, but the polymer meterability in the plurality of ejection holes is remarkably lowered, and the single yarn uniformity is inferior. Discharge hole contamination is likely to occur during long-term continuous spinning.
[0008]
The PTT polymer residence time Y (minute) in the present invention needs to be 181.8-0.639X or more with respect to the set spinning temperature X (° C.). Below this,
Not only does the polymer fluidity significantly decrease and stable spinning becomes difficult, but the pressure of the polymer filtration section inside the spinning pack increases, and the polymer tends to leak, making it impossible to perform continuous spinning for a long period of time. Further, the PTT polymer residence time Y (min) needs to be 230.3-0.791X or less with respect to the set spinning temperature X (° C.). If this is exceeded, the PTT polymer will be thermally deteriorated, which will cause spun yarn breakage and generation of fuzz in subsequent processes. That is, the relationship between the PTT polymer residence time Y and the spinning temperature X in the present invention is within the shaded area shown in FIG.
[0009]
The spinning temperature X (° C.) in the present invention, as shown in FIG. 2, indicates the temperature detected by the spinning temperature detector 4 attached to the embedded and insulated polymer pipe from the extruder 2, and is a PTT polymer. The residence time Y (minutes) passed through the polymer pipe from the time when the pressure detected by the extruder tip pressure detector 3 installed at the outlet showed 0.9 MPa when the polymer extrusion was started from the outlet of the extruder. The time required for discharging from the spinneret 7 is shown.
[0010]
In the present invention, it is necessary to apply to the spinneret surface a silicone-based mold release agent that does not contain a phenyl group and has a heating loss rate of 50% or less. By using a silicone-based mold release agent that does not contain a phenyl group, the polymer mold release property is good, the deposit on the die surface can be suppressed, and the heating weight loss rate is 50% or less. This has the effect of extending the wiping cycle to 40 hours or more and improving production efficiency. More preferably, the heating weight loss rate is 40% or less. In addition, the solution viscosity of the silicone release agent is preferably 20 to 60 poise, and when the solution viscosity is less than 20 poise, spots are likely to occur when applied to the die surface, and the effect of the release agent is not uniform. When the solution viscosity exceeds 60 poise, the viscosity becomes too high, so that the base surface is more likely to become dirty. The heat loss rate in the silicone release agent is about 1.5 g of the silicone release agent collected in a stainless steel 70 mm petri dish, weighed with an electronic balance, and stored in a high temperature bath at 285 ° C. It is a value (%) obtained by dividing the weight loss when the weight is measured again after 168 hours by the weight before heating. For example, if the weight before heating is 1.5 g, and the weight after heating for 168 hours is 1.2 g, the heating loss rate is (1.2−1.5) ÷ 1.5 × 100 = 20%. The solution viscosity in the silicone release agent is a value (poise) measured at room temperature using a B-type viscometer.
[0011]
In the polytrimethylene terephthalate used in the present invention, a copolymer component such as isophthalic acid, 2-2bis {4- (β-hydroxy) phenyl} propane, etc., as long as the effect of the present invention is not impaired, if necessary, Matting agents such as titanium oxide, antioxidants such as hindered phenol compounds, pigments, hard-twisting agents, antibacterial agents, deodorants, conductivity-imparting agents and the like may be blended. In the spinning of the present invention, polytrimethylene terephthalate is preferably carried out by drying a pellet once processed to a moisture content of 100 ppm or less in order to prevent hydrolysis in an extruder or a polymer pipe. . More preferably, the water content is 50 ppm or less.
[0012]
In the present invention, the method for taking up the yarn discharged from the spinneret is not particularly limited. The method proposed in Japanese Patent Application Laid-Open No. 11-172526, that is, a molten multifilament extruded from the spinneret is directly below the die. After passing through a heat-retaining region having a length of 2 to 80 cm and maintaining an ambient temperature of 30 to 200 ° C., rapid cooling is suppressed and rapidly cooled to a first roll of 40 to 70 ° C. as a solid multifilament. Wound at 300 to 4000 m / min, then wound around a second roll at 120 to 160 ° C., stretched 1.5 to 3.0 times between the first roll and the second roll, and slower than the second roll The winding method or the method proposed in Japanese Patent Application Laid-Open No. 2000-73230, that is, after spinning and solidifying the spun yarn, the internal ambient temperature Is passed through a cylindrical heating device at 120 to 220 ° C., heat-treated, cooled again, taken up at a take-up speed of 3000 m / min or more, and subjected to a relaxation heat treatment at a relaxation rate of 4 to 12% and wound up. Any method may be adopted.
[0013]
【Example】
Hereinafter, the present invention will be described in more detail with reference to examples. In addition, the main measuring methods in the Example of this invention are as follows.
[0014]
1. This is a value (IV) obtained by dissolving 0.8 g of a sample polymer in 10 ml of intrinsic viscosity orthochlorophenol (hereinafter abbreviated as OCP) and calculating the relative viscosity ηr by the following equation using an Ostwald viscometer at 25 ° C.
[0015]
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]
2. Wiping Cycle Under the spinning conditions of each example, spinning was performed 5 times by simultaneous spinning of 8 yarns, and the average value of the time until yarn breakage occurred was defined as the wiping cycle.
[0017]
3. Thread quality Using the Toray fly counter shown in Fig. 3, the number of fluffs measured for a yarn length of 30000m was measured (pieces / piece / piece) while unraveling the resulting 8 multifilament packages at a speed of 550m / min. The evaluation was as follows.
[0018]
○: The number of fluff is less than 0.5 / 10,000 m Δ: The number of fluff is 0.6 to 1 / 10,000 m
X: The number of fluff exceeds 1-5 pieces / 10,000 m.
[0019]
Example 1
Using a spinneret in which 36 holes having a pore diameter of 0.24 mm and a hole depth of 0.4 mm are concentrically arranged from a PTT polymer having an intrinsic viscosity of 1.47 dried to a moisture content of 48 ppm at a spinning temperature of 255 ° C. After extruding at a discharge rate of 25.54 g / min and once cooling with cooling air at a wind speed of 40 m / min and a temperature of 20 ° C., the yarn was heated with a cylindrical heating device with an internal atmosphere temperature of 180 ° C. and a length of 1 m, After cooling again, 0.8% of the finishing agent is applied to the yarn with an oil supply guide located 40 cm below the cylindrical heating device, and further entangled with an entanglement nozzle located 30 cm below the room temperature. Was taken up at a speed of 2620 m / min with a first roll of No. 1 and subsequently 4.0% relaxation was given to the second roll at room temperature, and then the yarn was wound up with a winder to obtain 97 dtex 36 filaments. of To obtain a drawn yarn. At this time, a commercially available uniaxial extruder was used as the extruder, and the volume of the polymer piping and the filtration part in the pack was adjusted so that the polymer residence time was 28 minutes. Further, the spinneret was coated with a dimethylsilicone release agent having a heating loss ratio of 46% and a solution viscosity of 42 poise, and spinning was started. The wiping cycle at this time shows a stable spinnability of 53 hours, and the obtained yarn has a strength of 3.0 cN / dtex and an elongation of 90%, and can be actually used for false twisting or mixed fiber composite processing. It has a level of quality. The results are summarized in Table 1.
[0020]
Examples 2-9, Comparative Examples 2-7
Spinning was carried out in the same manner as in Example 1 except that the type of release agent, spinning temperature, and polymer residence time were changed. The polymer residence time was adjusted by changing the polymer piping and the filtration capacity in the pack. In Examples 5 and 6, a dimethyl silicone mold release agent having a heating weight loss rate of 28% and a solution viscosity of 21 poise was used. In Examples 8 and 9, a dimethyl silicone mold release agent having a heating weight loss ratio of 34% and a solution viscosity of 31 poise was used. The agent was used. In the comparative example, a dimethylsilicone mold release agent having a heating loss rate of 28% and a solution viscosity of 21 poise, which had the longest and best wiping cycle in the examples, was used. Under the spinning conditions within the scope of the present invention, the wiping cycle is 40 hours or more in all the examples, and the quality of the obtained yarn is good for use in processed yarn applications such as false twisting and mixed fiber composite processing. there were. On the other hand, under spinning conditions outside the scope of the present invention, not only the wiping cycle is insufficient for actual production, but also the number of fluffs of the obtained yarn is large, and the yarn provided in the spinning machine There were problems such as fluff that was cut off and adhered to road regulation guides and entanglement guides, and accumulated scum was generated by cutting the yarn surface. The results are summarized in Table 1.
[0021]
Comparative Example 1
In Comparative Example 1, the volume of the polymer pipe and the filtration part in the pack was adjusted so that the polymer residence time was 25 minutes at a spinning temperature of 250 ° C., and a dimethyl silicone mold release agent having a solution weight loss of 21 poise and a heat loss rate of 28% was obtained. After coating and spinning in the same manner as in Example 1, yarn breakage occurred frequently, and the wiping cycle was 4 hours. In addition, the PTT polymer was not able to maintain sufficient fluidity in the polymer piping, causing discharge spots at the spinneret and variations in single yarn fineness.
[0022]
Comparative Example 8
The polymer pipe and the filtration part volume in the pack were adjusted so that the polymer residence time was 0.5 minutes, and a dimethylsilicone mold release agent having a solution viscosity of 21 poise at a heating weight loss rate of 28% was applied. An attempt was made to spin the PTT polymer in the same manner, but PTT polymer extrusion spots from the extruder occurred, and the connection between the polymer pipe and the spinning pack polymer inflow part and leakage of the PTT polymer in the pack occurred. It became impossible to actually spin. This seems to be due to excessive pressure loss when passing through the polymer piping and the filtration part in the pack.
[0023]
[Table 1]

X = 255, Y = 18.555-28.59
X = 260, Y = 15.66-24.64
X = 265, Y = 12.465-20.685
X = 270, Y = 9.27 to 16.73
X = 280, Y = 2.88 to 8.82
[0024]
【The invention's effect】
As described above, according to the present invention, when spinning a PTT polymer, the spinning temperature and the polymer residence time are set within an appropriate range, and a specific silicone release agent is applied to the spinneret surface for a long time. Even when spinning, there is little dirt around the nozzle discharge hole, it suppresses the occurrence of yarn breakage, yarn unevenness, and fluff, improves the defects of the conventional polytrimethylene terephthalate spinning method, and the wiping cycle is 40 hours or more As a result, it is possible to obtain a yarn having stable continuous spinnability and a quality suitable for false twisting and mixed fiber composite processing.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram showing the scope of the present invention. FIG. 2 is a schematic diagram showing the outline of a spinning machine for carrying out the present invention. Explanation of symbols]
1: PTT dry tip hopper 2: Single screw extruder 3: Extruder tip pressure detector 4: Spinning temperature detector 5: Spinning heat retention box 6: Spinning pack filtration unit 7: Spinneret 8: Yarn 9: Chimney yarn cooling Device 10: cylindrical heating device 11: oil supply guide 12: entanglement nozzle 13: first roll 14: second roll 15: package 16: package 17: fluff detector 18: unwinding device 19: yarn suction device 20: fly Counter body

Claims (1)

Above 80 mol% is composed of trimethylene terephthalate repeating units polytrimethylene terephthalate in which polyester spinning yarn temperature X (° C.), the polymer residence time in the spinning machine and Y (min), the following equation (1) and ( In the case of spinning satisfying 2) at the same time, it is characterized in that a silicone mold release agent which does not contain a phenyl group, has a heat loss rate of 50% or less, and has a solution viscosity of 20 to 60 poise is applied to the spinneret surface. A method for spinning polytrimethylene terephthalate fibers.
181.8−0.639X ≦ Y ≦ 230.3−0.791X (1)
255 ≦ X ≦ 280 (2)

Images