JPH05239711A - Dry-wet spinning process and apparatus therefor - Google Patents
Dry-wet spinning process and apparatus thereforInfo
- Publication number
- JPH05239711A JPH05239711A JP7523992A JP7523992A JPH05239711A JP H05239711 A JPH05239711 A JP H05239711A JP 7523992 A JP7523992 A JP 7523992A JP 7523992 A JP7523992 A JP 7523992A JP H05239711 A JPH05239711 A JP H05239711A
- Authority
- JP
- Japan
- Prior art keywords
- spinning
- coagulation bath
- flow
- liquid
- dry
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000001891 gel spinning Methods 0.000 title claims description 24
- 238000000034 method Methods 0.000 title claims description 24
- 238000009987 spinning Methods 0.000 claims abstract description 63
- 230000015271 coagulation Effects 0.000 claims abstract description 54
- 238000005345 coagulation Methods 0.000 claims abstract description 54
- 239000007788 liquid Substances 0.000 claims abstract description 54
- 239000000835 fiber Substances 0.000 claims abstract description 29
- 239000002904 solvent Substances 0.000 claims abstract description 12
- 239000012298 atmosphere Substances 0.000 claims abstract description 7
- 239000004372 Polyvinyl alcohol Substances 0.000 claims description 29
- 229920002451 polyvinyl alcohol Polymers 0.000 claims description 29
- 230000001112 coagulating effect Effects 0.000 claims description 10
- 238000001816 cooling Methods 0.000 claims description 3
- 238000001125 extrusion Methods 0.000 abstract 1
- IAZDPXIOMUYVGZ-UHFFFAOYSA-N Dimethylsulphoxide Chemical compound CS(C)=O IAZDPXIOMUYVGZ-UHFFFAOYSA-N 0.000 description 10
- 239000011550 stock solution Substances 0.000 description 9
- 238000006116 polymerization reaction Methods 0.000 description 7
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 6
- LYCAIKOWRPUZTN-UHFFFAOYSA-N Ethylene glycol Chemical compound OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 description 3
- ZMXDDKWLCZADIW-UHFFFAOYSA-N N,N-Dimethylformamide Chemical compound CN(C)C=O ZMXDDKWLCZADIW-UHFFFAOYSA-N 0.000 description 3
- 229920000297 Rayon Polymers 0.000 description 3
- 229920003235 aromatic polyamide Polymers 0.000 description 3
- 238000007796 conventional method Methods 0.000 description 3
- 238000004090 dissolution Methods 0.000 description 3
- 238000001035 drying Methods 0.000 description 3
- PEDCQBHIVMGVHV-UHFFFAOYSA-N Glycerine Chemical compound OCC(O)CO PEDCQBHIVMGVHV-UHFFFAOYSA-N 0.000 description 2
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000012530 fluid Substances 0.000 description 2
- 238000009434 installation Methods 0.000 description 2
- 239000004973 liquid crystal related substance Substances 0.000 description 2
- 239000012046 mixed solvent Substances 0.000 description 2
- 230000000704 physical effect Effects 0.000 description 2
- 239000002964 rayon Substances 0.000 description 2
- 239000012783 reinforcing fiber Substances 0.000 description 2
- 229920005989 resin Polymers 0.000 description 2
- 239000011347 resin Substances 0.000 description 2
- 238000007127 saponification reaction Methods 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- CYSGHNMQYZDMIA-UHFFFAOYSA-N 1,3-Dimethyl-2-imidazolidinon Chemical compound CN1CCN(C)C1=O CYSGHNMQYZDMIA-UHFFFAOYSA-N 0.000 description 1
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 1
- 239000004677 Nylon Substances 0.000 description 1
- 239000004698 Polyethylene Substances 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 229910000147 aluminium phosphate Inorganic materials 0.000 description 1
- 239000003963 antioxidant agent Substances 0.000 description 1
- 239000003518 caustics Substances 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- ZURAKLKIKYCUJU-UHFFFAOYSA-N copper;azane Chemical compound N.[Cu+2] ZURAKLKIKYCUJU-UHFFFAOYSA-N 0.000 description 1
- QKSIFUGZHOUETI-UHFFFAOYSA-N copper;azane Chemical compound N.N.N.N.[Cu+2] QKSIFUGZHOUETI-UHFFFAOYSA-N 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 238000000578 dry spinning Methods 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 235000011187 glycerol Nutrition 0.000 description 1
- 238000007654 immersion Methods 0.000 description 1
- 229910017053 inorganic salt Inorganic materials 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000000155 melt Substances 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000012299 nitrogen atmosphere Substances 0.000 description 1
- 229920001778 nylon Polymers 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 239000000049 pigment Substances 0.000 description 1
- 229920002239 polyacrylonitrile Polymers 0.000 description 1
- -1 polyethylene Polymers 0.000 description 1
- 229920000573 polyethylene Polymers 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- 230000008929 regeneration Effects 0.000 description 1
- 238000011069 regeneration method Methods 0.000 description 1
- 238000011282 treatment Methods 0.000 description 1
- 238000002166 wet spinning Methods 0.000 description 1
Landscapes
- Artificial Filaments (AREA)
- Spinning Methods And Devices For Manufacturing Artificial Fibers (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、ポリビニルアルコール
（以下、ＰＶＡと略記する。）系繊維の乾湿式紡糸方
法、さらに詳しくは、高強度、高弾性率ＰＶＡ系繊維を
製造するために高ドラフトで生産性よく乾湿式紡糸する
ための方法及びその装置に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dry-wet spinning method for polyvinyl alcohol (hereinafter abbreviated as PVA) fibers, and more specifically, a high draft and high draft for producing PVA fibers. The present invention relates to a method and apparatus for dry-wet spinning with high productivity.
【０００２】[0002]
【従来の技術】ＰＶＡ系繊維は汎用繊維の中では最も高
強度、高初期弾性率を有しているため、ゴム補強用繊
維、セメント補強用繊維として広範に用いられている。
ＰＶＡ系繊維は、ＰＶＡの水溶液を苛性アルカリや無機
塩を含む凝固浴中に、凝固浴中に配設された紡糸口金か
ら紡糸するいわゆる湿式紡糸方法、あるいは含水ＰＶＡ
を溶融押し出し機中で溶解させ、紡糸口金から加熱空気
中に押し出す乾式紡糸方法によって製造されるのが一般
的である。2. Description of the Related Art PVA-based fibers have the highest strength and the highest initial elastic modulus among general-purpose fibers, and are therefore widely used as rubber-reinforcing fibers and cement-reinforcing fibers.
The PVA fiber is a so-called wet spinning method in which an aqueous solution of PVA is spun in a coagulation bath containing a caustic alkali or an inorganic salt from a spinneret arranged in the coagulation bath, or a hydrous PVA.
Is generally melted in a melt extruder, and is generally produced by a dry spinning method in which it is extruded from a spinneret into heated air.
【０００３】しかしながら、これらの方法で得られる繊
維の強度や弾性率は理論的に予測される値よりもはるか
に低いものにとどまっており、このため強度、弾性率を
高める種々の試みがなされている。例えば、ポリエチレ
ンにおいて成功を収めたいわゆるゲル紡糸方法をＰＶＡ
に適用した例として、特開昭63−165509号公報の方法が
あげられる。この方法は、ＰＶＡを溶媒に溶解して調製
した紡糸原液を、冷却浴あるいは凝固浴中に不活性雰囲
気層（エアギャップ）を通して乾湿式紡糸し、得られた
未延伸糸を高倍率に延伸するものである。However, the strength and elastic modulus of the fibers obtained by these methods are much lower than the theoretically predicted values, and various attempts have been made to increase the strength and elastic modulus. There is. For example, the so-called gel spinning method that has been successful in polyethylene is the PVA
The method described in Japanese Patent Application Laid-Open No. 63-165509 can be cited as an example applied to the above. In this method, a spinning dope prepared by dissolving PVA in a solvent is dry-wet spun through an inert atmosphere layer (air gap) in a cooling bath or a coagulation bath, and the obtained unstretched yarn is stretched at a high draw ratio. It is a thing.
【０００４】本発明者らは、乾湿式紡糸方法について詳
細な検討を加えた結果、エアギャップ部で紡糸原液流に
高いドラフトをかけ、高伸張変形をさせた状態で紡糸す
ることが高強度化に大きく寄与することを見いだし、先
に特開平２−210013号公報において、紡糸口金直下の凝
固浴内に液中ロールを設け、このロールを回転させて糸
条を引き取ることにより紡糸原液流に高いドラフトをか
ける方法を提案した。しかしながら、さらに検討を進め
た結果、この方法は液中ロールを用いるため与えられる
最高ドラフト率に限界があること、また、単糸の切断が
生じた際にロールに糸が巻き付く等の問題があることが
明かとなった。The inventors of the present invention conducted a detailed study on the dry-wet spinning method, and as a result, a high draft was obtained by applying a high draft to the spinning stock solution flow in the air gap portion and performing spinning in a state of high elongation deformation. It was found that in the Japanese Unexamined Patent Publication (Kokai) No. 210013/1990, a submerged roll is provided in the coagulation bath immediately below the spinneret, and this roll is rotated to take up the yarn, thereby increasing the spinning stock solution flow. Proposed a way to draft. However, as a result of further study, this method has a limit in the maximum draft rate given by using the submerged roll, and there is a problem that the yarn is wound around the roll when the single yarn is cut. It became clear.
【０００５】一方、流下紡糸筒を用いる紡糸方法として
は、パラ系アラミド繊維の液晶紡糸方法が著名であり、
また、銅アンモニアレーヨン繊維や、ビスコースレーヨ
ン、ポリアクリロニトリル繊維を高速紡糸する方法が、
特公平３-70006号公報、特公平３−72721 号公報等で提
案されている。パラ系アラミド繊維の液晶紡糸方法は、
剛直な分子鎖であるパラ系アラミドポリマーの溶液を高
ドラフト下で紡糸することにより分子鎖を配向させ、そ
のまま凝固させて配向度の高い高強度、高弾性率繊維を
得ようとするものである。On the other hand, as a spinning method using a down-flow spinning cylinder, a liquid crystal spinning method of para-aramid fiber is well known,
In addition, a method of high-speed spinning copper ammonia rayon fiber, viscose rayon, polyacrylonitrile fiber,
It is proposed in Japanese Examined Patent Publication No. 3-70006 and Japanese Examined Patent Publication No. 3-72721. Liquid crystal spinning method of para-aramid fiber,
A solution of a para-aramid polymer, which is a rigid molecular chain, is spun in a high draft to orient the molecular chain and coagulate as it is to obtain a high-strength, high-modulus fiber with a high degree of orientation. ..
【０００６】また、銅アンモニアレーヨン繊維等を高速
紡糸する方法は、凝固、再生に用いる液体から糸条が受
ける抵抗を低減し、糸切れや単糸切れの発生を抑制しよ
うとするものであり、二重漏斗や突出した細管を配列し
た紡糸口金を用いる方法等が提案されている。Further, the method of spinning copper-ammonium rayon fiber or the like at high speed is intended to reduce the resistance of the yarn from the liquid used for coagulation and regeneration and suppress the occurrence of yarn breakage or single yarn breakage. A method using a double funnel or a spinneret in which protruding thin tubes are arranged has been proposed.
【０００７】しかしながら、ＰＶＡを溶媒に溶解して調
製した紡糸原液を、凝固浴中に形成させた高速液流で引
き取ることにより高ドラフト下で紡糸するという方法は
これまで検討されたことも、提案されたこともなかっ
た。However, it has also been proposed that a method of spinning a stock solution prepared by dissolving PVA in a solvent by a high-speed liquid stream formed in a coagulation bath to carry out spinning under a high draft has been studied so far. It was never done.
【０００８】[0008]
【発明が解決しようとする課題】したがって、本発明
は、ＰＶＡ溶液を高ドラフト下で紡糸して、高強度、高
弾性率ＰＶＡ系繊維を生産性よく製造する方法及びその
ための装置を提供することを技術的な課題とするもので
ある。Therefore, the present invention provides a method for spinning a PVA solution under a high draft to produce a high-strength, high-modulus PVA-based fiber with high productivity, and an apparatus therefor. Is a technical issue.
【０００９】[0009]
【課題を解決するための手段】本発明者らは、上記の課
題を解決するために鋭意研究を進めた結果、本発明に到
達した。すなわち、本発明は次の構成を有するものであ
る。[Means for Solving the Problems] The inventors of the present invention have arrived at the present invention as a result of intensive research to solve the above problems. That is, the present invention has the following configurations.
【００１０】(1) ＰＶＡを溶媒に溶解して調製した紡糸
原液を、紡糸口金から不活性雰囲気層を通して凝固浴中
に吐出して未延伸糸を形成させるに際し、凝固浴中に形
成させた平均流速が５ｖ以上の高速液流により、吐出さ
れた糸条を引き取ることを特徴とするＰＶＡ系繊維の乾
湿式紡糸方法。ただし、ｖは紡糸原液の紡糸口金からの
吐出線速度である。(1) An unstretched yarn is formed by discharging a spinning dope prepared by dissolving PVA in a solvent into a coagulation bath from a spinneret through an inert atmosphere layer to form an unstretched yarn. A dry-wet spinning method for PVA-based fibers, characterized in that the discharged yarn is collected by a high-speed liquid flow having a flow velocity of 5 v or more. However, v is the discharge linear velocity of the spinning dope from the spinneret.
【００１１】(2) 環状流路の内部に液体を噴射して、流
路に高速液流を発生させることのできるアスピレーター
を、吐出された未延伸糸が環状流路の内部を高速液流と
同方向に走行するように凝固浴又は冷却浴の中に配設し
たことを特徴とする乾湿式紡糸装置。(2) An aspirator capable of injecting a liquid into the annular flow passage to generate a high-speed liquid flow in the flow passage, and the undrawn yarn discharged causes the high-speed liquid flow inside the annular flow passage. A dry-wet spinning device, which is arranged in a coagulation bath or a cooling bath so as to run in the same direction.
【００１２】(3) 下部に流下紡糸筒を有する第１凝固浴
と、前記流下紡糸筒の下方に設けられた第２凝固浴から
なる乾湿式紡糸装置であって、第１凝固浴の液面が第２
凝固浴の液面より高く、前記流下紡糸筒の下部が下方に
向けてテーパー状に形成されて細管となり、その細管の
端部が第２凝固浴の液中に開口しており、第１凝固浴液
が細管中を流下して高速液流が発生するように配したこ
とを特徴とする乾湿式紡糸装置。(3) A dry-wet spinning apparatus comprising a first coagulation bath having a down-flow spinning tube at the bottom and a second coagulation bath provided below the down-flow spinning tube, the liquid level of the first coagulation bath Is the second
It is higher than the liquid level of the coagulation bath, and the lower part of the down-flowing spinning cylinder is formed in a downward tapered shape to form a thin tube, and the end of the thin tube opens into the liquid of the second coagulating bath, and A dry-wet spinning device characterized in that the bath liquid is arranged so as to flow down in a thin tube to generate a high-speed liquid flow.
【００１３】以下、本発明についてさらに詳しく説明す
る。The present invention will be described in more detail below.
【００１４】本発明において用いるＰＶＡは、重合度が
1500以上であることが好ましい。重合度が1500よりも低
いと、いかに高ドラフト下で紡糸しても、得られる繊維
の性能が十分なものとなり難い。なお、本発明でいう重
合度とは、ＪＩＳ−Ｌ−1716に記載の方法に準じて、濃
度１％水溶液の30℃における粘度から算出されるもので
ある。また、ＰＶＡのケン化度は特に限定されるもので
はないが、99.8モル％以上であることが望ましい。The PVA used in the present invention has a degree of polymerization of
It is preferably 1500 or more. If the degree of polymerization is lower than 1500, it will be difficult for the obtained fiber to have sufficient performance, no matter how high the draft is spun. The degree of polymerization referred to in the present invention is calculated from the viscosity of a 1% aqueous solution at 30 ° C. according to the method described in JIS-L-1716. The degree of saponification of PVA is not particularly limited, but is preferably 99.8 mol% or more.
【００１５】このようなＰＶＡを溶媒に溶解して紡糸原
液を調製するのであるが、溶媒としては、ジメチルスル
ホキシド、ジメチルホルムアミド、1,3-ジメチル-2-イ
ミダゾリジノン、エチレングリコール、グリセリン、水
等、あるいはこれらの混合溶媒を用いることができる。
中でもジメチルスルホキシド、あるいはジメチルスルホ
キシドと水との混合溶媒が好適に用いられる。A stock solution for spinning is prepared by dissolving such PVA in a solvent. As the solvent, dimethyl sulfoxide, dimethylformamide, 1,3-dimethyl-2-imidazolidinone, ethylene glycol, glycerin, water are used. Etc., or a mixed solvent thereof can be used.
Among them, dimethyl sulfoxide or a mixed solvent of dimethyl sulfoxide and water is preferably used.
【００１６】溶解は可能な限り低温で、短時間で行うの
が好ましく、しかも窒素雰囲気下、又は減圧下で行うの
がよい。具体的には95〜 120℃の温度で１〜４時間、−
60〜−75cmＨｇ程度の減圧下で撹拌しつつ溶解を行うの
が好ましい。ＰＶＡの濃度は、用いるＰＶＡの重合度に
応じて設定すればよいが、生産性を高める観点からでき
るだけ高濃度である方が好ましく、例えば重合度1700程
度のＰＶＡを用いる場合は10〜35重量％、重合度4000程
度のＰＶＡを用いる場合は５〜30重量％となるようにす
るのがよい。さらに、望むならば溶解する際、顔料や酸
化防止剤等を、繊維性能や紡糸性を損なわない程度に添
加してもよい。また、リン酸を添加しておくと、得られ
る繊維の耐溶剤性や耐熱性を高めることができるので好
ましい。The dissolution is preferably carried out at a temperature as low as possible and in a short time, and more preferably in a nitrogen atmosphere or under reduced pressure. Specifically, at a temperature of 95-120 ° C for 1-4 hours,
It is preferable to carry out the dissolution while stirring under a reduced pressure of about 60 to -75 cmHg. The concentration of PVA may be set according to the degree of polymerization of PVA to be used, but it is preferable that the concentration is as high as possible from the viewpoint of increasing productivity. For example, when using PVA having a degree of polymerization of about 1700, 10 to 35% by weight is preferable. When using PVA having a degree of polymerization of about 4000, it is preferable to set it to 5 to 30% by weight. Furthermore, if desired, pigments, antioxidants and the like may be added to the extent that they do not impair the fiber performance and spinnability when they are dissolved. In addition, it is preferable to add phosphoric acid because the solvent resistance and heat resistance of the obtained fiber can be improved.
【００１７】このようにして調製された紡糸原液は、紡
糸口金からエアギャップを通して凝固浴中へ吐出され
る。紡糸口金としては、中空円筒状細管を紡糸原液出口
側に突起を形成するように埋め込んだものを用いるのが
好ましい。中空円筒状細管の内径（Ｄ）は特に限定され
るものではないが、吐出線速度（ｖ）が0.５〜10ｍ／分
となるように設定し，Ｄを0.１〜1.５mmとするのが好ま
しい。また、中空円筒状細管の長さ（Ｌ）は、内径との
比（Ｌ／Ｄ) が２〜10となるように設定するのが好まし
い。The spinning dope thus prepared is discharged from the spinneret into the coagulation bath through the air gap. As the spinneret, it is preferable to use a hollow cylindrical thin tube embedded so as to form a protrusion on the outlet side of the stock solution for spinning. The inner diameter (D) of the hollow cylindrical thin tube is not particularly limited, but the discharge linear velocity (v) is set to be 0.5 to 10 m / min, and D is set to 0.1 to 1.5 mm. Preferably. The length (L) of the hollow cylindrical thin tube is preferably set so that the ratio (L / D) to the inner diameter is 2-10.
【００１８】エアギャップの長さは特に限定されるもの
ではないが、短すぎると高いドラフトが吸収されないの
で好ましくない。また、長すぎると紡糸原液細流の自由
流下速度が速くなりすぎ、凝固浴に突入した際に糸条が
いわゆるクリンプ状となるので好ましくない。適切なエ
アギャップの長さは、吐出線速度（ｖ）、紡糸温度、紡
糸原液の粘度等を勘案して決定されるが、通常３〜50mm
である。The length of the air gap is not particularly limited, but if it is too short, a high draft cannot be absorbed, which is not preferable. On the other hand, if it is too long, the free-flowing velocity of the spinning stock solution trickle becomes too fast, and the yarn becomes so-called crimp when it enters the coagulation bath, which is not preferable. The appropriate air gap length is determined in consideration of the discharge linear velocity (v), the spinning temperature, the viscosity of the spinning dope, etc., but it is usually 3 to 50 mm.
Is.
【００１９】紡糸口金から吐出された紡糸原液細流は凝
固液により凝固作用を受け、表面から凝固が進行し固化
糸条となる。本発明では、この固化糸条を、凝固浴内に
形成させた平均流速５ｖ以上の高速液流により引き取る
ことが極めて重要である。すなわち、固化糸条は高速液
流で引き取られることにより引張り応力を受けるが、こ
の応力は糸条を紡糸口金の方向へ伝播し、不活性雰囲気
層中の紡糸原液の細流に到る。したがって、発生した強
い引張り応力は紡糸原液細流を強く伸張するように作用
する。この伸張により、紡糸原液細流中の分子鎖は相互
にスリップし、存在していた絡み合いが解きほぐされて
配向が高まるのである。高速液流の速度が５ｖ未満では
ドラフトが低く、本発明の目的が達成されない。高速液
流の速度は７ｖ以上であることが好ましく、より好まし
くは10ｖ以上である。The spinning stock solution fine stream discharged from the spinneret is subjected to a coagulation action by the coagulation liquid, and coagulation proceeds from the surface to become a solidified yarn. In the present invention, it is extremely important that the solidified yarn is taken up by the high-speed liquid flow having an average flow velocity of 5 v or more formed in the coagulation bath. That is, the solidified yarn is subjected to a tensile stress by being taken up by the high-speed liquid flow, and this stress propagates in the yarn toward the spinneret, leading to a narrow stream of the spinning dope in the inert atmosphere layer. Therefore, the generated strong tensile stress acts to strongly stretch the spinning liquid dope. By this extension, the molecular chains in the spinning dope trickle slip with each other, the existing entanglement is unraveled, and the orientation is enhanced. If the speed of the high-speed liquid flow is less than 5 v, the draft is low and the object of the present invention cannot be achieved. The velocity of the high-speed liquid flow is preferably 7 v or higher, more preferably 10 v or higher.
【００２０】引き取られた糸条は、ガイドやロールで走
行方向を通常は横向きに変えられ、さらに抽出工程や乾
燥工程、さらには延伸工程に供給されるが、これらの処
理の方法は特に限定されるものではない。The yarn taken up can be changed in its running direction to a horizontal direction by a guide or a roll, and then supplied to an extracting step, a drying step, and a drawing step, but the method of these treatments is not particularly limited. Not something.
【００２１】次に、本発明の第１の乾湿式紡糸装置につ
いて、その一実施態様を示す図面により説明する。Next, the first dry-wet spinning device of the present invention will be described with reference to the drawings showing one embodiment thereof.
【００２２】図１において、１は紡糸口金、２は紡糸原
液の供給管、３はアスピレーターである。図２はアスピ
レーター３の部分断面図である。アスピレーター３は内
筒４と外筒５から構成されており、内筒にはスリット６
が設けられている。スリット６は、内筒４の中心軸に向
かって入射角θをなすように形成されており、スリット
６から噴出する液体が内筒４の内部を図の上部から下部
へ向かって流れるようにしてあり、これにより負圧が形
成される。図２の例では負圧を形成するためにスリット
を採用したが、スリットに代えて同様に内筒４の中心軸
に向かう孔を所望の数だけ設けてもよい。外筒５には流
体を供給するための導入孔７が設けられている。糸条は
アスピレーター３の内筒４内に形成された負圧により惹
起される高速液流により引き取られ、内筒４内を図の上
部から下部に向かって走行する。In FIG. 1, 1 is a spinneret, 2 is a spinning stock solution supply pipe, and 3 is an aspirator. FIG. 2 is a partial sectional view of the aspirator 3. The aspirator 3 is composed of an inner cylinder 4 and an outer cylinder 5, and the inner cylinder has a slit 6
Is provided. The slit 6 is formed so as to form an incident angle θ toward the central axis of the inner cylinder 4, so that the liquid ejected from the slit 6 flows through the inner cylinder 4 from the upper part to the lower part in the figure. Yes, this creates a negative pressure. In the example of FIG. 2, the slit is used to form the negative pressure, but instead of the slit, a desired number of holes facing the central axis of the inner cylinder 4 may be provided. The outer cylinder 5 is provided with an introduction hole 7 for supplying a fluid. The yarn is taken up by the high-speed liquid flow caused by the negative pressure formed in the inner cylinder 4 of the aspirator 3, and travels in the inner cylinder 4 from the upper part to the lower part in the figure.
【００２３】高速液流の流速は、内筒の内径、スリット
の幅、スリットの入射角、流体の供給量を適宜調整する
ことによって自由に設定することができるが、本発明の
目的を達成するためには、紡糸原液の紡糸口金での吐出
線速度ｖの５倍以上の流速となるように設定する必要が
ある。このような液流が形成されるものであればアスピ
レーターの寸法は特に限定されるものではないが、内筒
の内径が３〜15mm、外筒の外径が25〜70mm、内筒のスリ
ットより下部の長さが50〜 200mm程度のものが製作も容
易であり、取扱いも簡便で好ましい。The flow velocity of the high-speed liquid flow can be freely set by appropriately adjusting the inner diameter of the inner cylinder, the width of the slit, the incident angle of the slit, and the supply amount of the fluid, but the object of the present invention is achieved. In order to achieve this, it is necessary to set the flow rate of the stock solution for spinning at 5 times or more the discharge linear velocity v at the spinneret. The size of the aspirator is not particularly limited as long as such a liquid flow is formed, but the inner cylinder has an inner diameter of 3 to 15 mm, the outer cylinder has an outer diameter of 25 to 70 mm, and the inner cylinder has a slit. It is preferable that the lower part has a length of about 50 to 200 mm because it is easy to manufacture and easy to handle.
【００２４】導入孔７の取付位置は外筒のどの部分でも
よいが、外筒の外周の接線方向に取付ると内部に旋回流
が生じ、形成される負圧を強めることができる。アスピ
レーターの設置位置は特に限定されるものではないが、
紡糸口金直下、凝固浴液面から３〜50cmの深さに設置す
るのが好ましい。設置位置が浅すぎると紡糸口金外周部
分の糸条の集束角度が大きくなりすぎ、また、深すぎる
と高速液流の効果がエアギャップ部に伝播し難くなるの
で好ましくない。The introduction hole 7 may be attached at any position of the outer cylinder, but if it is attached in the tangential direction of the outer circumference of the outer cylinder, a swirling flow is generated inside and the negative pressure formed can be strengthened. The installation position of the aspirator is not particularly limited,
It is preferable to install it immediately below the spinneret at a depth of 3 to 50 cm from the surface of the coagulation bath. If the installation position is too shallow, the yarn converging angle in the outer peripheral portion of the spinneret becomes too large, and if it is too deep, the effect of the high-speed liquid flow becomes difficult to propagate to the air gap portion, which is not preferable.
【００２５】次に、本発明の第２の乾湿式紡糸装置につ
いて説明する。Next, the second dry-wet spinning device of the present invention will be described.
【００２６】図３において、８は流下紡糸筒、９は第１
凝固浴槽である。流下紡糸筒８は第１凝固浴槽９の底部
に配設されている。10は凝固液の第１凝固浴槽への供給
口であり、供給された凝固液は上昇して第１凝固浴９を
満たし、さらに流下紡糸筒８内を流下する。流下紡糸筒
の下部はテーパー状に細くなり、細管11になめらかに接
続しており、細管11内に高速液流が形成されるようにな
っている。12は流下紡糸筒の下方に設けられた第２凝固
浴槽であり、凝固液13が満たされている。細管11はその
開口部が凝固液13内に位置するように配設されている。In FIG. 3, 8 is a down-flow spinning cylinder, and 9 is a first spinning cylinder.
It is a coagulation bath. The down-flow spinning cylinder 8 is arranged at the bottom of the first coagulation bath 9. Reference numeral 10 denotes a supply port of the coagulation liquid to the first coagulation bath, the supplied coagulation liquid rises to fill the first coagulation bath 9, and further flows down in the down-flow spinning cylinder 8. The lower part of the down-flow spinning tube is tapered and thinly connected to the thin tube 11 so that a high-speed liquid flow is formed in the thin tube 11. A second coagulation bath 12 is provided below the down-flow spinning cylinder, and is filled with a coagulation liquid 13. The thin tube 11 is arranged so that its opening is located in the coagulating liquid 13.
【００２７】従来型の先端部が空気中にある流下紡糸筒
を用いた場合、流下した凝固液は空中に飛散するという
問題があるが、上記のように、紡糸筒の下部の細管の開
口部を凝固液内に位置させることが本発明の特徴であ
り、このような流下紡糸筒を用いることにより糸条は高
ドラフト下で紡糸され、しかも凝固液が空中に飛散する
ことが全くない。これは凝固液としてアルコールのよう
な揮発性や引火性の高い液体を用いるＰＶＡの紡糸にお
いては極めて有利な点である。さらに、液中ロールのよ
うな機械的駆動部が全くないので、糸条がロールに巻き
付くといったような問題も生じない。When a conventional down-flowing spinning cylinder whose tip is in the air is used, there is a problem that the coagulating liquid that has flowed down is scattered in the air. However, as described above, the opening of the thin tube at the bottom of the spinning tube is used. The present invention is characterized in that the coagulating liquid is positioned in the coagulating liquid, and by using such a down-flow spinning cylinder, the yarn is spun under a high draft, and the coagulating liquid is never scattered in the air. This is an extremely advantageous point in PVA spinning using a highly volatile or flammable liquid such as alcohol as the coagulating liquid. Further, since there is no mechanical driving unit such as the submerged roll, there is no problem that the yarn is wound around the roll.
【００２８】本発明において、流下紡糸筒の寸法は特に
限定されるものではないが、細管の内径は0.２〜2.０c
m、特に0.５〜1.０cmが好ましい。また、第１凝固浴の
液面と、流下紡糸筒下方の第２凝固浴の液面とのヘッド
差（Ｈ）を１〜30cmとするのが好ましい。これによっ
て、流下紡糸筒の下部から細管内を流下する凝固液の流
速を容易に５ｖ以上とすることができる。ヘッド差
（Ｈ）を１〜30cmに保持することは当業者ならば特別な
工夫を要することなく実施できる。例えば、２つの凝固
浴それぞれにオーバーフロー管14、15を設け、オーバー
フロー管から凝固液が常にオーバーフローするように凝
固液を供給すればよい。In the present invention, the size of the down-flow spinning cylinder is not particularly limited, but the inner diameter of the thin tube is 0.2-2.0c.
m, especially 0.5 to 1.0 cm is preferred. The head difference (H) between the liquid level of the first coagulation bath and the liquid level of the second coagulation bath below the down-spinning tube is preferably 1 to 30 cm. As a result, the flow rate of the coagulating liquid flowing down from the lower part of the down-flow spinning cylinder into the thin tube can be easily set to 5 v or more. It is possible for those skilled in the art to maintain the head difference (H) at 1 to 30 cm without special measures. For example, overflow pipes 14 and 15 may be provided in each of the two coagulation baths, and the coagulation liquid may be supplied so that the coagulation liquid always overflows from the overflow pipes.
【００２９】また、第１凝固浴の液面から流下紡糸筒の
上端までの距離 (Ｄ1)、細管までの距離 (Ｄ2)、及び細
管の第２凝固浴内での浸漬深さ (Ｄ3)はいずれも限定さ
れるものではないが、Ｄ1 は10〜40cm、Ｄ2 は15〜50c
m、Ｄ3 は0.５〜20cmとするのが好ましい。上記のよう
な本発明の乾湿式紡糸装置を構成する各部材の材質は特
に限定されず、金属、樹脂、セラミックス、ガラス等、
あるいはこれらの組み合わせを用いることができる。Further, the distance (D 1 ) from the liquid surface of the first coagulation bath to the upper end of the down-spinning tube, the distance (D 2 ) to the capillary, and the immersion depth (D) of the capillary in the second coagulation bath (D 3 ) are not limited, but D 1 is 10 to 40 cm and D 2 is 15 to 50 c.
m and D 3 are preferably 0.5 to 20 cm. The material of each member constituting the dry-wet spinning device of the present invention as described above is not particularly limited, and includes metal, resin, ceramics, glass, and the like.
Alternatively, a combination of these can be used.
【００３０】[0030]
【作用】本発明において、高強度、高初期弾性率を有す
るＰＶＡ系繊維が得られるのは、乾湿式紡糸のエアギャ
ップ部において紡糸原液の細流に高いドラフトをかける
ことによりＰＶＡ分子鎖が伸長変形し、分子鎖の絡み合
いが解きほぐされ、熱延伸により高度に配向可能な未延
伸繊維構造が形成されるためと認められる。In the present invention, the PVA fiber having high strength and high initial elastic modulus is obtained because the PVA molecular chain is stretched and deformed by applying a high draft to the trickle of the spinning dope in the air gap portion of dry-wet spinning. However, it is considered that the entanglement of the molecular chains is disentangled and a highly orientable unstretched fiber structure is formed by hot stretching.
【００３１】[0031]
【実施例】次に本発明を実施例により具体的に説明す
る。EXAMPLES Next, the present invention will be specifically described by way of examples.
【００３２】実施例１ 重合度4000、ケン化度99.9モル％のＰＶＡを濃度が15重
量％となるようにジメチルスルホキシドに溶解した。溶
解は−60cmＨｇの減圧下、 115℃で３時間撹拌しながら
行った。このようにして調製した紡糸原液を、内径0.45
mm、長さ３mmの中空円筒状細管 232本をナイロン樹脂に
埋め込んだ紡糸口金から、30mmの不活性雰囲気層を通し
て、図２に示すようなアスピレーターを、凝固浴内、液
面から10cm下方に配した紡糸装置を用いて乾湿式紡糸し
た。このとき紡糸原液の紡糸口金からの吐出線速度は3.
６ｍ／分であり、アスピレーターには引き取り速度が3
6.0ｍ／分となるように(すなわちドラフトが10.0となる
ように)凝固液を供給した。Example 1 PVA having a degree of polymerization of 4000 and a degree of saponification of 99.9 mol% was dissolved in dimethyl sulfoxide so as to have a concentration of 15% by weight. The dissolution was performed under a reduced pressure of -60 cmHg at 115 ° C for 3 hours with stirring. The spinning dope prepared in this way had an inner diameter of 0.45
2 mm hollow cylindrical capillaries with a length of 3 mm are embedded in nylon resin through a spinneret, and an aspirator as shown in Fig. 2 is placed 10 cm below the liquid level in the coagulation bath through a 30 mm inert atmosphere layer. Dry-wet spinning was performed using the spinning device described above. At this time, the linear velocity of the spinning dope discharged from the spinneret is 3.
6m / min, the aspirator has a pick-up speed of 3
The coagulating liquid was supplied so that the flow rate was 6.0 m / min (that is, the draft was 10.0).
【００３３】その後、凝固糸条を凝固浴外の第１引き取
りロールで12ｍ／分の速度で引き取り、常法に従って溶
媒除去、乾燥を行った後、熱延伸して1500ｄ／232fのＰ
ＶＡ繊維を得た。得られた繊維は、ヤーン強度21.2ｇ／
ｄ、初期弾性率 488ｇ／ｄ、伸度5.３％という優れた物
性を有していた。また、紡糸時に単糸の切断等は全く発
生せず、紡糸の調子は良好であった。After that, the coagulated yarn is taken out at a speed of 12 m / min outside the coagulation bath at a speed of 12 m / min, the solvent is removed and dried according to a conventional method, and then hot drawing is carried out to obtain a P of 1500 d / 232f.
VA fiber was obtained. The obtained fiber has a yarn strength of 21.2 g /
It had excellent physical properties of d, initial elastic modulus of 488 g / d and elongation of 5.3%. Further, the single yarn was not cut at the time of spinning, and the spinning condition was good.
【００３４】比較例１ 実施例１において、アスピレーターへの凝固液の供給量
を減らし、引き取り速度が15ｍ／分となるようにして乾
湿式紡糸し、凝固糸条を凝固浴外の第１引き取りロール
で12ｍ／分の速度で引き取った。その後、この糸条を常
法に従い、溶媒除去、乾燥を行った後、熱延伸してＰＶ
Ａ繊維を得たが、得られた繊維のヤーン強度は15.4ｇ／
ｄ、初期弾性率は 320ｇ／ｄに過ぎなかった。Comparative Example 1 In Example 1, the amount of coagulation liquid supplied to the aspirator was reduced and the wet speed was 15 m / min. At a speed of 12 m / min. Then, the yarn is subjected to solvent removal and drying according to a conventional method, and then hot stretched to form a PV.
A fiber was obtained, and the yarn strength of the obtained fiber was 15.4 g /
d, the initial elastic modulus was only 320 g / d.
【００３５】実施例２ 図３に示すような流下紡糸筒からなる凝固浴を用いて実
施例１と同様に乾湿式紡糸し、凝固糸条を流下する凝固
液（メタノール85重量％、ジメチルスルホキシド15重量
％）と一緒に曳糸し、紡糸筒下部に連なる直長部を経て
第２凝固浴に導いた。このときＤ1 は15cm、Ｄ2 は20c
m、Ｄ3 は５cmであり、Ｈは５cmとし、直長部での引き
取り速度が40ｍ／分となるようにした。Example 2 A coagulation liquid (85% by weight of methanol, 15% by weight of dimethylsulfoxide, 15% by weight) was used for dry-wet spinning in the same manner as in Example 1 using a coagulation bath consisting of a down-flow spinning cylinder as shown in FIG. (% By weight) and was led to the second coagulation bath via the straight length section connected to the lower part of the spinning tube. At this time, D 1 is 15 cm and D 2 is 20 c
m and D 3 were 5 cm, H was 5 cm, and the take-up speed in the straight part was 40 m / min.
【００３６】その後、この糸条を常法に従い、溶媒除
去、乾燥を行った後、熱延伸して1500ｄ／232fのＰＶＡ
繊維を得た。得られた繊維は、ヤーン強度20.4ｇ／ｄ、
初期弾性率 457ｇ／ｄ、伸度5.４％という優れた物性を
有していた。また、紡糸時に単糸の切断等は全く発生せ
ず、紡糸の調子は良好であった。Thereafter, this yarn was subjected to solvent removal and drying according to a conventional method, and then hot stretched to obtain 1500 d / 232 f PVA.
Fiber was obtained. The obtained fiber has a yarn strength of 20.4 g / d,
It had excellent physical properties such as an initial elastic modulus of 457 g / d and an elongation of 5.4%. Further, the single yarn was not cut at the time of spinning, and the spinning condition was good.
【００３７】[0037]
【発明の効果】本発明の乾湿式紡糸方法によれば、高強
度、高初期弾性率を有するＰＶＡ系繊維を生産性よく製
造することが可能である。また、本発明の乾湿式紡糸装
置は、凝固浴中に機械的な駆動部が全くないため、メタ
ノールのような揮発性、引火性の溶媒を用いるＰＶＡの
乾湿式紡糸に好適である。EFFECTS OF THE INVENTION According to the dry-wet spinning method of the present invention, PVA-based fibers having high strength and high initial elastic modulus can be produced with high productivity. Further, since the dry-wet spinning device of the present invention has no mechanical driving part in the coagulation bath, it is suitable for dry-wet spinning of PVA using a volatile and flammable solvent such as methanol.
【図１】本発明のアスピレーターを凝固浴内に配した乾
湿式紡糸装置の一実施態様を示す概略説明図である。FIG. 1 is a schematic explanatory view showing an embodiment of a dry-wet spinning device in which the aspirator of the present invention is placed in a coagulation bath.
【図２】図１で使用するアスピレーターの一実施態様を
示す部分断面図である。FIG. 2 is a partial cross-sectional view showing an embodiment of the aspirator used in FIG.
【図３】本発明の流下紡糸筒を使用した乾湿式紡糸装置
の一実施態様を示す概略説明図である。FIG. 3 is a schematic explanatory view showing one embodiment of a dry-wet spinning device using the down-flow spinning tube of the present invention.
１ 紡糸口金 ２ 紡糸原液の供給管 ３ アスピレーター ８ 流下紡糸筒 ９ 第１凝固浴 11 細管 12 第２凝固浴 1 Spinneret 2 Supply Tube for Spinning Liquid 3 Aspirator 8 Falling Spindle 9 First Coagulation Bath 11 Capillary Tube 12 Second Coagulation Bath
フロントページの続き (72)発明者 望月 政嗣 京都府宇治市宇治小桜23番地 ユニチカ株 式会社中央研究所内Front page continued (72) Inventor Masatsugu Mochizuki 23 Uji Kozakura, Uji City, Kyoto Prefecture Unitika Ltd. Central Research Laboratory
Claims (3)
調製した紡糸原液を、紡糸口金から不活性雰囲気層を通
して凝固浴中に吐出して未延伸糸を形成させるに際し、
凝固浴中に形成させた平均流速が５ｖ以上の高速液流に
より、吐出された糸条を引き取ることを特徴とするポリ
ビニルアルコール系繊維の乾湿式紡糸方法。ただし、ｖ
は紡糸原液の紡糸口金からの吐出線速度である。1. When a spinning dope prepared by dissolving polyvinyl alcohol in a solvent is discharged into a coagulation bath from a spinneret through an inert atmosphere layer to form an undrawn yarn,
A dry-wet spinning method for polyvinyl alcohol-based fibers, characterized in that the discharged yarn is collected by a high-speed liquid flow having an average flow velocity of 5 v or more formed in a coagulation bath. However, v
Is the discharge linear velocity of the spinning dope from the spinneret.
に高速液流を発生させることのできるアスピレーター
を、吐出された未延伸糸が環状流路の内部を高速液流と
同方向に走行するように凝固浴又は冷却浴の中に配設し
たことを特徴とする乾湿式紡糸装置。2. An aspirator capable of injecting a liquid into the annular flow passage to generate a high-speed liquid flow in the flow passage, wherein the undrawn yarn discharged is the same as the high-speed liquid flow inside the annular flow passage. A dry-wet spinning device, which is arranged in a coagulation bath or a cooling bath so as to run in a predetermined direction.
と、前記流下紡糸筒の下方に設けられた第２凝固浴から
なる乾湿式紡糸装置であって、第１凝固浴の液面が第２
凝固浴の液面より高く、前記流下紡糸筒の下部が下方に
向けてテーパー状に形成されて細管となり、その細管の
端部が第２凝固浴の液中に開口しており、第１凝固浴液
が細管中を流下して高速液流が発生するように配したこ
とを特徴とする乾湿式紡糸装置。3. A dry-wet spinning apparatus comprising a first coagulation bath having a down-flow spinning tube at the bottom and a second coagulation bath provided below the down-flow spinning tube, wherein the liquid level of the first coagulation bath is Second
It is higher than the liquid level of the coagulation bath, and the lower part of the down-flowing spinning cylinder is formed in a downward tapered shape to form a thin tube, and the end of the thin tube opens into the liquid of the second coagulating bath, and A dry-wet spinning device characterized in that the bath liquid is arranged so as to flow down in a thin tube to generate a high-speed liquid flow.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7523992A JPH05239711A (en) | 1992-02-25 | 1992-02-25 | Dry-wet spinning process and apparatus therefor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7523992A JPH05239711A (en) | 1992-02-25 | 1992-02-25 | Dry-wet spinning process and apparatus therefor |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH05239711A true JPH05239711A (en) | 1993-09-17 |
Family
ID=13570471
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP7523992A Pending JPH05239711A (en) | 1992-02-25 | 1992-02-25 | Dry-wet spinning process and apparatus therefor |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH05239711A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112095159A (en) * | 2020-08-04 | 2020-12-18 | 东华大学 | High-strength coarse denier polyvinyl alcohol fiber spun by wet method and preparation method thereof |
| CN117702295A (en) * | 2023-12-08 | 2024-03-15 | 北京中丽制机工程技术有限公司 | Funnel and preparation method of core body thereof |
-
1992
- 1992-02-25 JP JP7523992A patent/JPH05239711A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112095159A (en) * | 2020-08-04 | 2020-12-18 | 东华大学 | High-strength coarse denier polyvinyl alcohol fiber spun by wet method and preparation method thereof |
| CN112095159B (en) * | 2020-08-04 | 2022-09-16 | 东华大学 | High-strength coarse denier polyvinyl alcohol fiber spun by wet method and preparation method thereof |
| CN117702295A (en) * | 2023-12-08 | 2024-03-15 | 北京中丽制机工程技术有限公司 | Funnel and preparation method of core body thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP3072442B2 (en) | Method for producing cellulosic article | |
| US5252284A (en) | Method of producing shaped cellulosic articles | |
| CN1132972C (en) | Spinning device | |
| TW202028552A (en) | Methods for producing carbon fiber precursor fiber and carbon fiber | |
| JPS59228012A (en) | Wet spinning process | |
| JPH05239711A (en) | Dry-wet spinning process and apparatus therefor | |
| JPS61108711A (en) | Production of polyvinyl alcohol fiber of high strength and high elastic modulus | |
| JPS61102413A (en) | Production of poly-paraphenylene terephthalamide yarn | |
| JP3799061B2 (en) | Method for making filaments from optically anisotropic spinning solution | |
| JP2007291594A (en) | Method for producing acrylic fiber bundle | |
| CN1239761C (en) | Method for producing continuous moulded bodies consisiting of cellulose | |
| BR0110198B1 (en) | process for forming lyocell fibers, and lyocell fiber. | |
| JPH01124610A (en) | Wet spinning of flow tube type | |
| JPS6065110A (en) | Production of poly-p-phenylene terephthalamide fiber | |
| US3219740A (en) | High speed tubular spinning of fine viscose rayon yarn | |
| JP2000273718A (en) | High-speed spinning method of polyvinyl alcohol fiber | |
| JP5441275B2 (en) | Method for producing a plurality of high strength, high modulus aromatic polyamide filaments | |
| JP2002294518A (en) | Carbon fiber precursor acrylonitrile yarn and method for producing the same | |
| JPS62141113A (en) | Production of fiber | |
| JPH04194014A (en) | Method for spinning acrylonitrile-based fiber | |
| CN1063726A (en) | Process for the manufacture of shaped fiber products | |
| JPH0152486B2 (en) | ||
| JPH02229208A (en) | Production of multifilament yarn | |
| JPH02300308A (en) | Polyvinyl alcohol fiber and production thereof | |
| JPH08109510A (en) | Elimination of sticking of fiber in dry jet-wet spinning |