JP2006342451A - Dry-wet spinning method and apparatus therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a dry-wet spinning method by which a spinning speed is heightened to improve the productivity, and a fiber having little dispersion of quality among single fibers constituting a yarn, and stable properties is obtained while suppressing the occurrence of single fiber breakage; and to provide an apparatus therefor. <P>SOLUTION: The dry-wet spinning method comprises spinning a spinning dope (D) from a spinning cap (1) having many spinning holes bored therein into a gaseous body, introducing the spun dope (D) into a coagulation liquid (La) flowing down in a flow tube (3) to coagulate the dope and to form the fiber, and taking up the fiberized yarn (Y), wherein a coagulation liquid (Lb) having a different solvent concentration contained in the coagulation liquid is injected to the midway of the flow tube (3), and the speed, the flow rate, the concentration and/or the temperature of the coagulation liquid flowing down in the flow tube (3) are regulated. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to dry-wet spinning in which a spinning dope is once spun into the air from a spinneret having a large number of spinning holes, and the spun dope is introduced into a flow tube through which a coagulating liquid flows to be fiberized. The present invention relates to a method and an apparatus thereof.

  As a conventional technique for spinning a wholly aromatic polyamide fiber having both high strength and high modulus, a solution dope containing a wholly aromatic polyamide polymer is once in the air from a spinneret having a larger number of spinning holes. It is well known that the dope stream is spun and then solidified by removing the solvent with a coagulating liquid and coagulating it. In the present invention, the state until the solvent is extracted from the spinning stock solution spun from the spinning hole formed in the spinneret and made into a fiber is collectively referred to as “dope”.

  However, when the dope is introduced into the coagulation bath storing the stationary coagulation liquid and coagulated, when the dope introduction speed exceeds a certain speed, the single fiber breakage occurs due to the resistance received from the coagulation liquid. For this reason, the introduction speed of the dope into the coagulation liquid cannot be increased, and therefore the spinning speed has to be reduced. In addition, when the spinning speed is increased, it is necessary to increase the immersion time (immersion length) in order to secure the time required for coagulation in the coagulation liquid as the speed increases, and the size of the apparatus is inevitably increased. There was a problem of becoming.

  Therefore, in order to increase the spinning speed, the dope is not introduced into the stationary coagulating liquid, but the dope is coagulated while reducing the resistance received from the coagulating liquid by flowing the coagulating liquid together with the running dope. Japanese Patent Application Laid-Open No. 60-52610 proposes a flow tube spinning method and an apparatus therefor.

  Certainly, according to this prior art, the spinning speed can be increased by increasing the flow rate of the coagulating liquid flowing down in the flow tube. However, in this prior art, it is difficult to match the dope speed in the flow tube with the flow rate of the solidified flow flowing down in the flow tube, and the single fiber breakage occurs, and stable spinning cannot be performed. Furthermore, in this prior art, the coagulating liquid flowing down in the flow tube is not newly added or replaced.

  For this reason, in a system that solidifies by desolvation, the solvent derived from the dope is extracted into the coagulating liquid as it passes through the flow tube, so that the solvent concentration of the coagulating liquid is increased and quality stability is impaired. In particular, when the number of single fibers constituting the yarn is increased in order to ensure productivity, the increase in the concentration of the solvent extracted from the dope into the coagulation liquid becomes more noticeable. Therefore, the problem becomes more serious, and the occurrence of single fiber breakage is more closely highlighted.

  Therefore, for example, in the technique disclosed in Japanese Patent Application Laid-Open No. 61-19805, a high-speed wet spinning method is proposed in which a fluid ejecting device and a gas ejecting device are provided on the downstream side of the flow tube for spinning. Certainly, according to this device, it is possible to increase the flow velocity in the flow tube by using the propulsive force of the fluid blown out by the fluid ejecting device, and it is possible to supply coagulating liquids having different concentrations from the ejecting device. High-speed spinning is possible in which the concentration of the coagulating liquid can be controlled in the process in which the spun dope is solidified and made into a fiber.

  However, in this type of prior art proposed in Japanese Patent Laid-Open No. 61-19805, for example, a free fall zone is formed between the flow tube and the fluid ejecting device, so that the dope or the yarn is fluid. When entering the injection device, a rapid change in the speed of the fluid occurs, and there arises a problem that the single fibers constituting the semi-solidified yarn in the course of the solidification process are broken.

JP 60-52610 A Japanese Patent Laid-Open No. 61-19805

  In view of the problems of the prior art described above, the problem to be solved by the present invention is that a spinning dope is once spun into the air from a spinneret having a large number of spinning holes and spun into a coagulation liquid. In dry-wet spinning, in which the dope is introduced into fibers, the spinning speed can be increased to improve productivity, and there is no quality variation among the single fibers constituting the yarn, and the single fibers are broken. It is an object of the present invention to provide a method and an apparatus capable of obtaining a fiber having a stable performance and capable of suppressing the occurrence of the above.

Here, as a wet spinning method according to the present invention for solving the above problems,
(1) After spinning a spinning solution into a gas from a spinneret having a number of spinning hole groups, the spinning solution is introduced into a coagulating solution that flows down in a flow tube, and then coagulated. In the dry-wet spinning method for taking up the fiberized yarn, the coagulating liquid having a different solvent concentration contained in the coagulating liquid is injected from the middle of the flow pipe, and the concentration of the coagulating liquid flowing down in the flow pipe is adjusted. Wet spinning method,
(2) The coagulating liquid maintained at a temperature different from the temperature of the coagulating liquid flowing down the flow pipe is injected into the flow pipe from the middle of the flow pipe, and the temperature of the coagulating liquid flowing down the flow pipe is adjusted. And the wet spinning method according to (1),
(3) The flow rate and / or flow rate of the coagulation liquid flowing down to the coagulation liquid injection position is controlled by the flow rate of the coagulation liquid supplied from the middle of the flow tube. (1) or (2) A wet spinning method, and
(4) The wet spinning method according to any one of claims 1 to 3, wherein the wholly aromatic polyamide fiber is dry-wet spun.

Next, as a wet spinning device according to the present invention that solves the above problems,
(5) A coagulation bath filled with a coagulation liquid, and a spinneret in which a number of spinning hole groups provided with a certain air gap from the liquid surface formed by the coagulation liquid filled in the coagulation bath are formed. And a flow tube that is immersed below the liquid surface and flows in the coagulation bath, and a coagulating liquid injector that injects fresh coagulated liquid into the flow tube from the middle of the flow tube And a dry-wet spinning device comprising at least thread take-up means provided below the flow tube,
(6) The wet spinning device according to (5), characterized by comprising a temperature control device that controls the temperature of the coagulation liquid injected in the middle of the flow tube to a constant level,
(7) The liquid injection part of the coagulation liquid injector that injects the coagulation liquid into the flow tube is provided with a pressure equalizing member that equalizes the injection pressure of the coagulation liquid in the liquid injection part (5) or (6 ) Wet spinning apparatus according to
(8) The liquid injection part of the coagulation liquid injector for injecting the coagulation liquid into the flow tube is provided with a rectifying member for rectifying the coagulation liquid in the liquid injection part, according to any one of (5) to (7) Wet spinning equipment, and
(9) The wet spinning device according to any one of (5) to (8), wherein the shape of the liquid injecting portion of the coagulating liquid injector that injects the coagulating liquid into the flow tube extends conically in the downstream direction. Is provided.

  As described above, according to the dry and wet spinning method and apparatus of the present invention, the spinning speed can be increased and the concentration and temperature in the flow tube can be arbitrarily set, so that the dope is solidified in the flow tube. Thus, fiberization can be performed efficiently. For this reason, the obtained yarn has an extremely remarkable effect that it can obtain a stable one with few single fiber breaks and no quality variation.

  The object of the present invention is a dry and wet spinning method suitable for producing a fully aromatic polyamide fiber having both high strength and high modulus, and an apparatus therefor.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a schematic configuration diagram schematically illustrating an embodiment of a dry / wet spinning apparatus according to the present invention, and FIG. 2 is an enlarged cross-sectional view schematically showing an essential part of FIG. It is. In FIG. 1, D represents a dope containing a polymer made of wholly aromatic polyamide, and Y represents a yarn obtained by extracting a solvent from such a dope and fiberized. Reference numeral 1 denotes a spinneret having a large number of spinning holes, 2 denotes a coagulating device, 3 denotes a flow tube, and 4 denotes a rotating body that takes up a yarn in which the dope is made into fibers.

  The coagulation apparatus 2 includes a coagulation bath 2a, a coagulation liquid supply pipe 2b, a coagulation liquid discharge pipe 2c, a coagulation liquid recovery means 2d, and a weir 2e. Symbol S represents the liquid level formed in the coagulation bath 2a by the coagulation liquid L, respectively.

  Hereinafter, an embodiment of a process in which a dope D containing a polymer made of wholly aromatic polyamide is fiberized to form a yarn Y using the dry and wet spinning apparatus according to the present invention will be described in detail.

  First, in the present invention, “dope” is used as the spinning dope. This “dope” can be adjusted, for example, as described below. That is, 112.9 parts of N-methyl-2-pyrrolidone (hereinafter referred to as NMP) having a moisture content of 100 ppm or less, 1.506 parts of paraphenylenediamine, and 2.789 parts of 3,4'-diaminodiphenyl ether at a room temperature. And after dissolving in nitrogen, 5.658 parts of terephthalic acid chloride is added with stirring. And finally, it is made to react at 85 degreeC for 60 minutes, and a transparent viscous polymer solution is obtained. Next, 9.174 parts of NMP slurry containing 22.5% by weight of calcium hydroxide is added and a neutralization reaction is performed to obtain the necessary “dope”.

  As described above, when the adjusted dope is made into fiber, first, using a metering means such as a gear pump, the dope is continuously metered and distributed to a spin block (not shown). The dope is spun from the spinneret 1 attached to the spin block. However, the spinneret 1 is, for example, a disc having an outer diameter of 100 mm with 1,000 spinning holes having a hole diameter of 0.5 mm, and the dope D is made into a fibrous form from these many spinning hole groups. It is to be spun. At that time, as illustrated in FIG. 1, an air gap G is formed between the liquid surface S formed by the coagulation liquid L and the dope discharge surface of the spinneret 1.

  If the air gap G is too small, the coagulation liquid L may come into contact with the dope discharge surface of the spinneret 1, and the dope discharged from the spinneret 1 will solidify immediately below the spinneret 1, Causes fiber breakage. If it is too large, adjacent yarns in the spinneret 1 are brought into close contact with each other, and independent fibers cannot be obtained. For this reason, the air gap G is suitably 1 mm or more and 50 mm or less in the spinneret 1, for example.

  As described above, the dope D discharged from the numerous spinning hole groups drilled in the spinneret 1 is once spun into the air, and then into the coagulation liquid L filled in the coagulation bath 2a. And then led to the flow tube 3. A flow tube 3 is inserted and fixed in the coagulation bath 2a in correspondence with the spinneret 1. The flow tube 3 is set at a position lower than the liquid level S formed by the coagulation liquid L. .

  Thus, since the upper end of the flow tube 3 is provided at a position lower than the liquid surface S of the coagulation bath 2a, if the distance from the liquid surface S of the coagulation bath 2a to the upper end portion of the flow tube 3 is small, the flow tube 3 Disturbance occurs in the coagulating liquid flow above the tube 3, and this is propagated to the liquid surface S, and the liquid surface S is disturbed. On the other hand, when this distance increases, the effect of stabilizing the flow of the coagulating liquid L due to the installation of the flow tube 3 is lost. Therefore, in order to stabilize the liquid level S of the coagulation bath 2a, the distance from the liquid level S to the upper end of the flow tube 3 needs to be 2 mm or more and 100 mm or less, preferably 5 mm or more and 50 mm or less. is there.

  Next, the shape suitable for the flow tube 3 of the present invention will be described. Since a certain amount of time is required for solidification to make the dope D spun from the spinneret 1 into a fiber, the length of the flow tube 3 is long. The length of a certain length is required. On the other hand, however, if the length of the straight cylinder at the bottom of the flow tube 3 is increased, an excessive frictional resistance acts between the inner wall surface of the flow tube 3 and the running yarn Y, and the yarn Y is rubbed strongly. I want to shorten it because it leads to single fiber breakage and thread breakage. Therefore, if these conditions are satisfied, it is preferable that the straight cylinder length L of the flow tube lower part 3b is 100 mm or more and 5000 mm or less.

  Regarding the inner diameter of the flow tube 3, for example, if the take-up speed of the yarn Y by the take-up means 4 is in the range of 10 m / min to 300 m / min, the number of single fiber groups constituting the yarn Y (filament As for the number), considering efficient production, 10 to 5000 pieces are required. Considering this point, the equivalent diameter of the yarn is 1 mm or more and 20 mm or less, and accordingly, the minimum inner diameter d of the flow tube 3 is preferably 2 mm or more and 30 mm or less.

  However, the final shape of the dope D discharged from the spinneret 1 is the amount of coagulating liquid La brought into the flow tube 3, the amount of dope D itself flowing into the flow tube 3, or the fiberized yarn Y Therefore, it is necessary to finally perform an experiment to meet these conditions and determine an optimum shape.

  Although not shown in FIG. 1, a rectifying member (not shown) is installed in the coagulation bath 2a as necessary to stabilize the flow of the coagulation liquid L supplied from the supply pipe 2b. It is a preferred embodiment in the present invention to supply the flow tube 3 while forming a simple flow. Examples of the rectifying member include a screen having excellent fluid passage properties such as a perforated plate, a honeycomb plate, and a woven or knitted fabric. It is desirable to provide in the vicinity.

  As described above, when the coagulation liquid present in the coagulation bath 2a and the flow tube 3 and the dope D come into contact with each other, the organic solvent contained in the dope D is extracted into the coagulation liquid and fiberized. As is well known, a yarn Y composed of a number of single fiber groups (multifilaments) made of a polymer made of wholly aromatic polyamide is formed.

  The yarn Y thus formed is then taken up by the rotating body 4 such as a take-up roller, and the water adhering in the water washing step and water washing step for removing the coagulating liquid L adhering to the yarn Y is dried. A series of yarn making processes including a drying step and a heat drawing step is performed. It is also well known that fibers having high performance and / or high function are obtained by this series of spinning processes.

  At that time, the coagulation liquid L for coagulating the spun dope into fibers is first supplied from the supply pipe 2b to the coagulation bath 2a while being controlled at a constant flow rate. Next, the coagulating liquid L supplied to the coagulation bath 2a in this way overflows and flows out from the weir 2e provided in the coagulation bath 2a. In this way, the weir 2e serves to maintain the level of the liquid surface S of the coagulating liquid stored in the coagulating bath 2a at a constant level. The excessive coagulating liquid L overflowed is recovered by the recovery means 2d and discharged from the discharge pipe 2c connected to the recovery means 2d.

  On the other hand, a part of the coagulation liquid L supplied to the coagulation bath 2a flows into the flow tube 3 provided below the level of the liquid surface S of the coagulation liquid, and the dope D spun from the spinneret 1 At the same time, it flows down in the flow tube 3. The flow tube 3 includes a bent tube portion 3a having an upper funnel shape and a straight tube portion 3b having a lower tubular shape. At this time, the straight pipe portion 3b of the flow pipe 3 is provided with a coagulating liquid injector 5 for adjusting the flow rate and flow rate of the coagulating liquid La flowing down the flow pipe 3 as shown in the figure.

  Here, the coagulating liquid injector 5 includes a liquid inlet part 5a for supplying the coagulating liquid Lb, a liquid storing part 5b for storing the supplied coagulating liquid L, and the stored coagulating liquid directly in the flow tube 3. It is comprised at least from the liquid injection | pouring part 5c injected and supplied in the pipe part 3b. Therefore, the coagulating liquid La supplied from the upper curved pipe portion 3a via the coagulation bath 2a and the coagulating liquid supplied from the liquid injection portion 5c to the flow tube 3 via the liquid storage portion 5b are supplied to the flow tube 3. Lb is injected. And the straight pipe part 3c formed under the flow pipe 3 flows down in the state which the said coagulating liquid La and the coagulating liquid Lb were mixed.

  As described above, in this example, the coagulating liquid Lb supplied from the coagulating liquid injector 5 is injected from the liquid injecting unit 5 c into the coagulating liquid La flowing down in the flow tube 3. Then, passage resistance can be applied to the coagulating liquid La flowing down in the upper portions 3a and 3b of the flow tube 3, and the speed and flow rate of the coagulating liquid La can be controlled. The speed and flow rate of the coagulating liquid La are controlled to desired values by adjusting the amount of the coagulating liquid Lb to be injected. That is, by appropriately adjusting the mixing ratio between the flow rate of the coagulation liquid Lb and the flow rate of the coagulation liquid La and the temperature and concentration of the coagulation liquid Lb to be injected, the temperature of the coagulation liquid La and the coagulation liquid Lb is adjusted. And the concentration can be adjusted appropriately.

  Thus, in the present invention, the flow velocity and flow rate of the coagulating liquid La flowing down in the flow tube 3 can be adjusted to desired values over the entire length of the flow tube. For this reason, the dope D spun from the spinneret 1 can be run together with a coagulating liquid having a controlled flow velocity, flow rate, temperature, and solvent concentration flowing down in the flow tube 3, thereby allowing the dope D to be extraneous. Thus, the fiberization rate of the dope D can be appropriately controlled without applying any additional tension. Therefore, there is an extremely remarkable effect that the dope D can be made into a fiber smoothly while suppressing the single fiber breakage that occurs in the coagulation liquid.

  Here, as the coagulating liquid that can be suitably used in the present invention, known ones described in JP-B-47-50219, JP-A-7-309958, etc., such as calcium chloride, lithium chloride, sodium chloride, Contains at least one inorganic salt selected from the group consisting of magnesium chloride, zinc chloride, strontium chloride, aluminum chloride, stannic chloride, nickel chloride, calcium bromide, zinc nitrate, and aluminum nitrate, per liter of water Examples thereof include an aqueous coagulation liquid in which the total content of the salts is at least 2 mol (anhydrous salt equivalent concentration). However, it is not limited thereto, and it goes without saying that other than these can be used as long as the gist of the present invention is satisfied.

  In the dry-wet spinning process in the series of yarn making processes as described above, the present invention is characterized in that, as already described, the coagulating liquid injector 5 is provided, thereby the flow tube 3. The concentration and temperature of the coagulating liquid L in the flow tube can be changed in the middle. Therefore, a method and apparatus for changing the concentration and temperature of the coagulating liquid flowing down the flow tube 3 by the coagulating liquid injector 5 will be described in detail below.

  As described above, the flow tube 3 is provided with the coagulating liquid injector 5 for adjusting the speed, flow rate, concentration and temperature of the coagulating liquid flowing in the flow tube 3. The coagulating liquid injector 5 has a liquid inlet portion 5 a for supplying a coagulating liquid Lb to be newly added to the flow tube 3. The liquid inlet portion 5a is supplied with a coagulating liquid Lb whose concentration is adjusted in advance via the temperature control device 6.

  However, the temperature control device 6 includes a known heating / cooling means for heating and / or cooling the coagulating liquid Lb supplied to the coagulating liquid injector 5, and the coagulating liquid Lb is heated to a predetermined constant temperature by the heating / cooling means. Control and maintain. Accordingly, the coagulating liquid Lb supplied to the liquid inlet portion 5a of the coagulating liquid injector 5 has a preset temperature in a state of surrounding the flow tube 3 from the liquid injecting portion 5c via the liquid storage portion 5b. The liquid is injected in a state of being stably metered at a constant flow rate from the entire circumference direction into the flow tube 3 while maintaining the concentration.

  At this time, the coagulating liquid La flowing down to the installation position of the coagulating liquid injector 5 together with the dope D in the flow tube 3, the organic solvent contained in the dope D into the coagulating liquid La while flowing in the flow pipe 3. The extracted concentration is higher than the initial concentration. When the temperature of the coagulating liquid La is lower than the temperature of the dope D, the temperature of the coagulating liquid La rises due to the heat transferred from the dope D to the coagulating liquid La.

  Then, if the coagulation liquid Lb in the flow tube 3 is caused to flow down in this state, the efficiency of extracting the solvent from the dope D into the coagulation liquid Lb is reduced, and the concentration of the organic solvent contained in the dope D reaches the target concentration. It takes time. Therefore, it is difficult to reduce the solvent concentration contained in the dope D to the target concentration while maintaining the organic solvent concentration in a short time. In particular, as the number of single fibers (the number of filaments) constituting the yarn to be fiberized increases, the concentration and temperature rise in the flow tube 3 become more significant, leading to a decrease in the physical properties of the resulting fiber.

  Therefore, by supplying additional coagulating liquid Lb having different concentrations and temperatures from the liquid injection part 5c of the coagulating liquid injector 5, and mixing and injecting the coagulating liquid La flowing in the flow tube 3, the concentration of the coagulating liquid and Adjust the temperature. The condition of the coagulating liquid Lb injected from the coagulating liquid injector 5 is generally that the concentration of the mixed liquid when the solution of the additional coagulating liquid Lb is mixed with the concentration of the coagulating liquid La is the concentration of the coagulating liquid L. It is desirable to be equal to or less than.

  At that time, for the reason described in the background art column, it is necessary to prevent the flow rate of the coagulating liquid La flowing down in the flow tube 3 from changing abruptly. Therefore, it is desirable that the connecting portion at the upper part of the flow tube 3 and the coagulating liquid injector 5 does not have a sudden diameter change.

  Further, regarding the liquid injection part 5c for supplying the coagulation liquid Lb, the liquid injection part 5c surrounds the flow tube 3 and plays a role of supplying the coagulation liquid Lb from the entire circumferential direction. Is preferably supplied uniformly into the flow tube 3 without disturbing the flow of the coagulating liquid La flowing down. Therefore, in order to realize this, the liquid injection part 5c is formed of a member having both a pressure equalizing effect and a rectifying effect, such as a woven or knitted fabric made of a well-known fine metal wire used as a filtration medium or a porous sintered metal. It is desirable to keep it.

  In particular, in order to supply the coagulation liquid Lb stably and uniformly from the liquid injection part 5c, the resistance by the fluid in the rectifying member is required to some extent. One or more open woven or knitted fabrics may be used in combination. However, in the present invention, there is no reason to limit to the woven or knitted fabric or the porous sintered metal, and as long as the gist of the present invention is satisfied, a material capable of obtaining a pressure equalizing and / or rectifying effect, such as a nonwoven fabric, a hole, etc. An opening plate or the like can also be used.

  The liquid injection part 5c does not necessarily have to be a member for both equalizing and rectifying the coagulating liquid Lb to be supplied, and may be configured to perform these functions separately. For example, as a rectifying member having a rectifying effect, a screen having excellent fluid permeability such as a perforated plate, a honeycomb plate, a woven or knitted fabric is provided, and further, a ceramic or metal whose porosity is appropriately controlled as a pressure equalizing member. You may make it provide separately the sintered compact which sintered the fine particle powder which becomes.

  As for the shape of the liquid injection part 5c, it is preferable not to change the flow rate of the coagulating liquid La flowing down the flow tube 3 rapidly. For this purpose, the coagulated liquid Lb injected into the flow tube 3 is used. In consideration of the increase in the flow rate, it is desirable to have a shape that expands in a conical shape toward the downstream side so that the average flow velocity in the flow tube 3 is constant.

  By this invention, the inventors pass through the flow tube 3 by using a flow tube device characterized by having a concentration and coagulation liquid injector 5 as illustrated in FIGS. The present inventors have come up with an apparatus that efficiently controls the organic solvent concentration of the dope D and does not affect the physical properties. For this reason, the yarn Y discharged from the spinneret 1 and landed from the liquid surface S of the coagulation bath is coagulated in the flow tube 3 having an appropriate concentration and temperature profile by the coagulation liquid Lb supplied by the coagulation liquid injector 5. By obtaining the liquid, it is possible to reduce the breakage of single fibers of the yarn Y finally obtained and the variation in quality.

It is the schematic block diagram which illustrated typically one Embodiment of the dry-wet spinning apparatus which concerns on this invention. It is sectional drawing which showed typically the example of 1 embodiment of the flow tube of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Spinneret 2 Coagulation apparatus 2a Coagulation bath 2b Coagulation liquid supply pipe 2c Coagulation liquid discharge pipe 2d Coagulation liquid collection means 2e Weir 3 Flow pipe 4 Yarn take-up means 5 Coagulation liquid injector 5a Coagulation liquid supply part 5b Coagulating liquid storage section 5c Coagulating liquid injection section D Dope L Coagulating liquid supplied to coagulating bath La Coagulating liquid supplied from coagulating bath into flow tube Lb Coagulating liquid supplied from coagulating liquid injector G Air gap S Coagulation bath surface Y Yarn

Claims (9)

  After spinning the spinning stock solution into a gas from a spinneret having a large number of spinning hole groups, the spinning solution is introduced into the coagulating solution flowing down in the flow tube and then coagulated to form fibers. In the dry-wet spinning method for pulling out the converted yarn, the coagulating liquid having a different solvent concentration contained in the coagulating liquid is injected from the middle of the flow pipe, and the concentration of the coagulating liquid flowing down in the flow pipe is adjusted. Wet spinning method.   The coagulating liquid maintained at a temperature different from the temperature of the coagulating liquid flowing down the flow tube is injected into the flow tube from the middle of the flow tube, and the temperature of the coagulating liquid flowing down in the flow tube is adjusted. Item 2. The wet spinning method according to Item 1.   The wet spinning method according to claim 1 or 2, wherein the flow rate and / or flow rate of the coagulating liquid flowing down to the coagulating liquid injection position is controlled by the flow rate of the coagulating liquid supplied from the middle of the flow tube.   The wet spinning method according to any one of claims 1 to 3, wherein the wholly aromatic polyamide fiber is dry-wet spun.   A coagulation bath filled with a coagulation liquid, a spinneret in which a plurality of spinning hole groups provided with a constant air gap and a liquid surface formed by the coagulation liquid filled in the coagulation bath are formed; A flow tube in which the coagulating liquid is immersed below the liquid surface and flows down in the coagulating bath; a coagulating liquid injector for injecting fresh coagulating liquid into the flow tube from the middle of the flow tube; A dry-wet spinning apparatus comprising at least a yarn take-up means provided below the flow tube.   6. The wet spinning apparatus according to claim 5, further comprising a temperature control device for controlling the temperature of the coagulating liquid injected in the middle of the flow tube to be constant.   The wet method according to claim 5 or 6, wherein a pressure equalizing member for equalizing an injection pressure of the coagulating liquid is provided in the liquid injecting part of the coagulating liquid injector for injecting the coagulating liquid into the flow tube. Spinning device.   The wet spinning device according to any one of claims 5 to 7, wherein a rectifying member that rectifies the coagulating liquid is provided in the liquid injecting portion of the coagulating liquid injector that injects the coagulating liquid into the flow tube.   The wet spinning device according to any one of claims 5 to 8, wherein the shape of the liquid injection portion of the coagulation liquid injector for injecting the coagulation liquid into the flow tube is conically diverged along the downstream direction.

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