JP2008231607A - Annular cooling apparatus for spinning and melt-spinning method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an annular cooling apparatus for spinning, having excellent air flow uniformity in the circumferential direction, and free from the trouble of the contact and fusion of yarns by the oscillation of the yarn in the production of a multifilament yarn to give a yarn having high quality. <P>SOLUTION: The annular cooling apparatus for spinning cools and solidifies a yarn formed by the melt-spinning of a thermoplastic polymer by blasting air flow to the yarn from the outside to the inside of the running path of the yarn. The apparatus is provided with an air-flow introducing pipe 20, a first buffer chamber 13 connected to the air-flow introducing pipe 20 and having an annular flow channel, an annular straightening member 11 positioned at the downstream of the annular flow channel of the first buffer chamber 13, a second buffer chamber 12 provided with an annular flow channel, having a cross-sectional area of the flow channel larger than that of the first buffer channel and positioned at the downstream side of the annular straightening member 11, and an annular straightening filter 5 placed inside of the second buffer chamber 12 and having a flow channel to blast air flow inward. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an annular cooling device for spinning and a melt spinning method.

  In the production of multifilament yarns, various researches and developments have been made on the method of stably cooling the thermoplastic polymer discharged from the spinneret, and it has been implemented in several device structures. ing. As a general cooling device, there is a wide range of cross-flow type cooling devices that cool the yarn discharged from the spout gold by blowing airflow in one direction perpendicular to the running direction of the yarn. As is known, spots are formed on the airflow blowing side and the cooling airflow between the filaments on the airflow anti-spraying side, so uniform cooling cannot be achieved, and there remains a problem of deterioration of thread property spots. . In particular, in the recent ultrafine and multifilamentization, the deterioration of thread property spots becomes remarkable. On the other hand, as another cooling device, there is an internal blow cooling device that blows an airflow inward from the outside of the yarn traveling path to the yarn discharged from the spinneret having the spinning holes arranged in an annular shape. is there.

  For example, Patent Document 1 discloses a cooling cylinder of a spinning cooling device as shown in FIG. FIG. 9 is a schematic longitudinal sectional view of the cylindrical portion of the spinning annular cooling device of Patent Document 1. 10 (1) and 10 (2) are development views of the cylindrical portion of FIG. In the figure, 5 represents a rectifying filter, 28 represents a porous cylinder, and 29 represents a nozzle hole. Hereinafter, in each drawing, when a member corresponding to the already-explained drawing exists, the description may be omitted by using the same reference numerals. The porous cylinder 28 having the nozzle holes 29 has a constant nozzle hole diameter in a predetermined cross section perpendicular to the yarn traveling direction and expands the nozzle hole diameter toward the downstream side in the yarn traveling direction, or the nozzle hole pitch. Is dense toward the downstream side in the running direction of the yarn, so that the passage resistivity when the airflow passes through the porous cylinder 28 is uniform in the circumferential direction and toward the downstream side in the running direction of the yarn. Increase for a while.

  Furthermore, as having the same function as described above, as shown in FIG. 11, a felt-shaped cloth 27 is wound around the porous cylinder 28 to reduce the thickness of the cloth wound toward the downstream side in the yarn traveling direction. There is something. FIG. 11 is a schematic longitudinal sectional view of a cylindrical portion of a conventional annular cooling device for spinning. According to these methods, when a heating cylinder is provided immediately below the spinneret, and then the air flow is blown out from the continuously provided cooling cylinder, the tension applied to the yarn is low and the accompanying flow is also small immediately below the heating cylinder. Therefore, by reducing the supply airflow at locations where yarn swaying occurs due to the blowing of airflow, and by supplying an amount of airflow commensurate with the accompanying flow at locations where accompanying flow is generated, It is described that contact and fusion can be avoided. However, according to the knowledge of the present inventors, even if an airflow of an amount corresponding to the yarn accompanying flow is appropriately performed in the yarn traveling direction, the air velocity of the airflow blown from the cooling cylinder is not uniform in the circumferential direction. As a result, the position of the accompanying flow is different between the yarns, the balance of the accompanying flow is lost in the cross section perpendicular to the yarn traveling direction, and contact and fusion between the yarns due to the turbulence of the air flow occur, Gets worse. With respect to the airflow flowing into the cooling cylinder, the structure of the cooling cylinder described above is insufficient to obtain circumferential wind speed uniformity.

  Further, Patent Document 2 discloses a spinning cooling device as shown in FIGS. FIG. 5 is a schematic longitudinal sectional view of the spinning annular cooling device of Patent Document 2. As shown in FIG. 6 is a BB arrow view of FIG. In the figure, 1 is an air flow supply port, 2 is an anti-air flow supply port, 3 is a cylindrical outer wall surface, 4 is a punching plate, 6 is a stagnation point, 7 is a baffle plate, and 8 is a buffer chamber. The spinning cooling device includes a buffer chamber 8 divided into two in the yarn traveling direction. Each buffer chamber 8 includes a punching plate 4 and a rectifying filter 5. By controlling the air velocity of the airflow blown out from the buffer chamber 8 on the side close to the base surface (the upper buffer chamber in FIG. 5), the heat-retaining property of the atmosphere immediately below the base surface is maintained, and the spinning cooling device outlet By increasing the wind speed of the airflow blown out from the buffer chamber 8 on the side close to (the lower buffer chamber in FIG. 5), the inflow of the airflow from the outside to the spinning cooling device induced by the yarn accompanying flow is prevented. Proposals have been made to prevent and avoid contact and fusion between yarns due to air current disturbance. In order to improve the pressure equalization of the buffer chamber 8, a method of setting the opening ratio of the punching plate 4 to 30 to 60% and a method of covering the punching plate 4 with a nonwoven fabric have been proposed.

  Here, the flow form of the airflow inside the spinning cooling device of Patent Document 2 will be described. The airflow supplied from the airflow supply port 1 flows into the anti-airflow supply port 2 along the cylindrical outer wall surface 3 of the buffer chamber 8 and simultaneously flows into the upper portion of the buffer chamber 8 to form the punching plate 4 and the rectifying filter 5. And is blown inward from the outside toward the traveling path of the yarn. In the anti-airflow supply port 2, airflows entering from both sides of the cylindrical outer wall surface 3 collide with each other and are accelerated by the collision energy to increase the wind speed, whereas the airflow supplied from the airflow supply port 1 At the point of direct collision with the baffle plate 7, a stagnation point 6 occurs and the wind speed decreases. Therefore, the anti-airflow supply side 2 is pressurized, the airflow supply port 1 becomes negative pressure, and a pressure imbalance occurs in the circumferential direction. Once this pressure imbalance occurs, even if it passes through the buffer chamber 8 and then passes through the rectifying member formed by the punching plate 4 and the rectifying filter 5, a sufficient rectifying effect cannot be obtained and the rectifying filter 5 is blown out. Unevenness in the circumferential direction of the wind speed occurs. Further, if the buffer chamber 8 does not have a constant volume space with respect to the supplied air volume, a pressure equalizing effect cannot be obtained, and it becomes difficult to reduce the pressure imbalance in the circumferential direction. In particular, since the baffle plate 7 is disposed inside the buffer chamber 8, the flow path that guides the airflow in the circumferential direction along the cylindrical outer wall surface 3 from the airflow supply port 1 is extremely narrowed. The occurrence of circumferential pressure imbalance is inevitable. Therefore, in the apparatus configuration disclosed in Patent Document 2, it is difficult to obtain circumferential wind speed uniformity of the airflow blown out from the rectifying filter 5. This is because, in the ultra-thin multifilament yarn having a single yarn fineness of 0.6 dtex and 300 filaments according to the example described in Patent Document 2, a very large value of less than 2% of Wooster's spots is used as a criterion for determining the quality of the yarn thickness spots. It is clear from the point of use, and it is impossible to achieve a high thread thickness spot requirement level of Worcester spot [H] of 0.5% or less. Further, there is no technical disclosure regarding the mode of the buffer chamber 8 that is important for the uniformity of the circumferential wind speed.

  Further, Patent Document 3 discloses a spinning cooling device having an apparatus configuration similar to that of Patent Document 2. Two or more buffer chambers 8 are continuously provided in the running direction of the yarn, the blowing length of the lowermost buffer chamber 8 farthest from the spinneret is 0.5 m or less, and the lowermost buffer chamber 8 It has been proposed that the blowing air speed be larger than the blowing air speed of any of the buffer chambers 8 arranged at the top. By using this technique, a high-speed air current is locally applied, so that the air current penetrates the yarn bundle and the hot air staying in the inner layer of the yarn bundle can be easily discharged to the outer layer of the yarn bundle. Rapid cooling is possible.

  However, since the apparatus configuration similar to the spinning cooling apparatus described in Patent Document 2 causes the problem of uneven circumferential wind speed as described above, the technical disclosure regarding the uniform wind speed in the circumferential direction occurs. There is no.

  Also, as shown in FIG. 12, a porous cylindrical filter 30 of a spinning cooling device is disclosed in Patent Document 4. FIG. 12 is a schematic cross-sectional view of a conventional annular cooling device for spinning. The porous cylindrical filter 30 has a function similar to that of the rectifying filter 5 described above. A technique has been proposed in which a paper filter 31 or a nonwoven fabric 31 having a high filtration resistance is wound around the entire outer periphery of the porous cylindrical filter 30 to provide a uniform wind speed distribution in the circumferential direction. When this technique is used, a filter 30 having a low circumferential resistance in the circumferential direction and a low filtration resistance is used on the inner periphery, and a paper filter 31 having a high circumferential resistance and a high filtration resistance or a nonwoven fabric 31 is provided on the outer periphery thereof. By adopting a wound two-layer structure, an air flow having a uniform wind speed in the circumferential direction can be supplied. As a result, there is no contact or fusion of the yarns, and a yarn having good yarn physical properties can be obtained. Furthermore, clogging of the porous cylindrical filter 30 is prevented, and by periodically replacing the paper filter 31 having a high filtration resistance on the outer peripheral side, melt spinning can be performed for a long time without any trouble.

  However, the circumferential wind speed distribution described in Patent Document 4 has a large variation in wind speed values and cannot be said to be sufficiently uniform. This is because the single yarn fineness of 4.6 dtex, discharge amount of 0.6 g / min / hole, winding speed of 1300 m / min, and multifilament yarn of 1000 to 2000 filaments in the example described in Patent Document 4 is changed in cross section. It is also clear from the fact that it is used as a quality judgment criterion for extremely large thickness spots of less than 4%, and the high thread thickness requirement level of Wooster spots [H] 0.5% or less It is clear that it cannot be achieved at all. Furthermore, there is no technical disclosure regarding the mode of the buffer chamber that is important for the uniformity of the circumferential wind speed.

  The spinning cooling device disclosed in Patent Document 5 will be described with reference to FIGS. 7 and 8 regarding the cooling device main body and the flow form of the airflow in the cooling device. FIG. 7 is a schematic longitudinal sectional view of a cylindrical portion of an annular cooling device for spinning disclosed in Patent Document 5. FIG. 8 is a view taken along the line CC in FIG. The spinning cooling device constitutes a baffle plate 7 at the airflow supply port 1. The airflow supplied from the airflow supply port 1 once collides with the baffle plate 7, reduces wind speed spots in the airflow introduction pipe 20, and the uniformized airflow flows along the cylindrical outer wall surface 3 of the buffer chamber 8. At the same time as it flows into the counter air flow supply side 2, it flows into the upper part of the buffer chamber 8 in sequence, passes through the rectifying filter 5, and is blown out as a uniform wind speed in the circumferential direction. By adopting such a configuration, it is possible to equalize the circumferential wind speed while maintaining the heat retention of the atmosphere immediately below the base surface, avoiding yarn contact and fusion due to air turbulence and reducing yarn property spots This is described in Patent Document 5.

  However, once the airflow is reduced and uniformed in the airflow introduction pipe 20, the airflow supply port 1 side generated by the airflow that circulates in the circumferential direction of the buffer chamber 8 and the antiairflow supply are then generated. The uneven circumferential wind speed due to the pressure imbalance on the side 2 cannot be sufficiently suppressed. Further, there is no rectifying member for reducing uneven circumferential wind velocity once generated there other than the rectifying filter 5 provided immediately before the air flow is blown out. Further, if the buffer chamber 8 does not have a constant volume space with respect to the supply air volume necessary for cooling the yarn, the pressure equalizing effect cannot be obtained, and it becomes difficult to reduce the pressure imbalance, and the circumferential wind speed is not good. Uniformity increases more and more. Therefore, the above-described apparatus configuration alone is insufficient to obtain the circumferential air velocity uniformity of the airflow finally blown out from the rectifying filter 5. Furthermore, in recent high speed spinning, ultra-fine fibers such as multi-filaments and multi-filaments, in the circumferential wind speed uniformity using the above device configuration, the required yarn properties It has become difficult to achieve spots. This is because, in the multifilament having a single yarn fineness of 5 dtex, a discharge amount of 1000 g / min, a take-off speed of 1000 m / min, and a filament number of 2000 in the example described in Patent Document 4, a very large value of 3% Wooster unevenness is obtained. It is clear from the fact that it is used as a standard for judging the quality of spots, and as a required level in recent years, for example, a high thread thickness required level such as Wooster spots [H] of 0.5% or less is achieved. Can not. Furthermore, while the thread thickness unevenness requirement level itself is increasing, further uniform wind speed in the circumferential direction is required.

  Further, Patent Document 6 discloses a spinning cooling device as shown in FIG. FIG. 13 is a schematic longitudinal sectional view of the spinning annular cooling device of Patent Document 6. As shown in FIG. The spinning cooling device includes a first gas chamber 33 and a second gas chamber 32, and a perforated plate 34 is provided on the boundary line between the first gas chamber 33 and the second gas chamber 32. Therefore, the airflow introduced from the airflow supply port 1 is first guided to the first gas chamber 33 to reduce airflow turbulence (jet), then passes through the perforated plate 34 and is guided to the second gas chamber 32. Can achieve pressure equalization. As a result, it is possible to eliminate the disturbance of the airflow that blows inward from the rectifying filter 5 toward the running path of the yarn, to avoid yarn contact and fusion, and to reduce yarn physical property unevenness. Further, it has been proposed to employ a punching plate having a hole diameter of 1 to 5 mm and a hole pitch of 5 to 10 mm, or a metal mesh of 100 to 500 mesh as the perforated plate 34. Further, it has been proposed to stack a plurality of effective plates 34 or to have two or more stages at appropriate intervals.

  However, as described in Non-Patent Document 1, the perforated plate 34 exhibits a rectifying effect by eliminating the disturbance when the resistance coefficient K such as the hole diameter, hole pitch, and interval of the punching plate is optimized. If the resistance coefficient K is set incorrectly for the air volume necessary for cooling the yarn, the disturbance becomes large and, on the contrary, the air current is disturbed. Once the airflow turbulence occurs once after passing through the perforated plate 34, since there is no rectifying mechanism other than the rectifying filter 5 thereafter, the circumferential wind speed non-uniformity increases. Also, the theoretical formula described in Non-Patent Document 1 is not a formalized formula but a model obtained by experiment, and it is actually necessary to find an optimum value in the shape of the annular channel. In particular, since the air volume required for cooling the yarn varies depending on various spinning conditions, it is necessary to determine the apparatus specifications such as the hole diameter, hole pitch, and interval of the perforated plate 34 according to each required air volume. The inside does not describe how much airflow is required. Therefore, the pressure imbalance state cannot be sufficiently suppressed only by the apparatus specifications described in the specification, and circumferential wind speed nonuniformity occurs. In particular, in the recent rapid increase in spinning speed, and ultrafine fibers such as multiple yarns and multifilaments, the circumferential wind speed uniformity using the above-described apparatus configuration is required for the yarn property irregularities. It has become difficult to achieve. This is a Wooster obtained from a multifilament undrawn yarn having a fineness of 50 denier (55.6 dtex) and a filament number of 24 (single yarn fineness of 2.08 denier (2.31 dtex)) in the examples described in the specification. Since the unevenness is set to 0.35%, for example, in an ultra-fine multifilament yarn having a single yarn fineness of 0.1 to 1.6 dtex, a high yarn thickness such as Wooster unevenness [H] is 0.5% or less. It is clear that the required level of plaque cannot be achieved.

To date, various technical studies have been made on spinning cooling devices other than Patent Documents 1 to 6, but the present inventors have performed airflow blowout velocity measurement of several types of spinning annular cooling devices. As a result, the circumferential wind speed spot in the general annular cooling device for spinning was 5%, and there were many that exceeded 10-20%. In addition, there has been no investigation to date of uniforming the circumferential air velocity of the blown airflow of the spinning cooling cylinder, and no adequate disclosure has been made in the annular cooling device for spinning and the melt spinning method. Therefore, for producing an ultrafine multifilament having a single yarn fineness of 0.1 to 1.6 dtex and a filament number of 2000 or less, yarn contact / fusion due to non-uniform wind speed in the circumferential direction of the airflow is likely to occur, Such as yarn swaying, thread thickness unevenness and quality such as strength and elongation are extremely deteriorated.Further, fluff and thread breakage occur frequently, and the stability of yarn production deteriorates, and even spinning is not possible. There were many problems.
JP-A 61-174411 JP 2003-253522 A JP 47-29616 A Japanese Patent Laid-Open No. 50-160513 JP 60-126309 A JP-A-46-65475 Japan Society of Mechanical Engineers, technical data, resistance coefficient of pipes and ducts, January 20, 1979, first edition, P109-P114 The Japan Society of Mechanical Engineers, technical data, resistance coefficient of pipes and ducts, January 20, 1979, first edition, P37-P50

  An object of the present invention is to obtain a yarn having excellent quality such as thickness unevenness of the yarn and strength / elongation, which is excellent in the uniform air velocity in the circumferential direction of the air current, without contact or fusion of the yarn due to yarn sway. Therefore, an object of the present invention is to provide an annular cooling device for spinning and a melt spinning method that exhibit a remarkable effect.

  In order to achieve the above object, an spinning cooling apparatus for cooling and solidifying by blowing an air flow inward from the outside of a running path of a yarn obtained by melt spinning a thermoplastic polymer, comprising: an air flow introduction pipe; A first buffer chamber having an annular flow path that communicates with the air flow introduction tube and surrounds the outside of the travel path of the yarn, and downstream of the annular flow path of the first buffer chamber. A ring-shaped rectifying member that is positioned so as to surround the outside of the travel path of the yarn and cover the entire downstream end of the annular flow path of the first buffer chamber, and the downstream of the ring-shaped rectifying member, A flow path break in a cross section perpendicular to the thread travel path on the first buffer chamber side of the ring-shaped rectifying member, having an annular flow path disposed so as to surround the outside of the thread travel path A second buffer chamber having a cross-sectional area larger than the area, and the second buff There is provided an annular cooling device for spinning, characterized in that it has an annular rectifying filter which is disposed inside the chamber so as to surround the outside of the running path of the yarn and has a flow path for blowing airflow inwardly. The

  According to a preferred aspect of the present invention, there is provided an annular cooling device for spinning, wherein a net buffer flow path length of the first buffer chamber is 3 mm or more and 80 mm or less.

Further, according to a preferred embodiment of the present invention, there is provided an annular cooling device for spinning, wherein dimensions of each part of the second buffer chamber satisfy the following expression (1).
0.09 ≦ D _2OUT ≦ 0.3 (m)
D _2INN / D _2OUT ≦ 0.95 (1)
Here, D _{2OUT represents} the outer diameter (m) of the second buffer chamber, and D _2INN represents the inner diameter (m) of the second buffer chamber.

  According to still another preferred aspect of the present invention, the spinning ring has a cylindrical rectifying member that rectifies the airflow with respect to the space including the traveling path of the yarn through the annular flow path of the second buffer chamber. A cooling device is provided.

  Further, according to another aspect of the present invention, when the thermoplastic polymer is melt-spun from the spinneret and airflow is blown inward from the outside of the running path of the spun yarn to cool and solidify, The air flow guided is guided to the first buffer chamber having an annular flow path that is communicated with the air flow introduction pipe and is disposed so as to surround the outside of the travel path of the yarn, and then the first buffer. Passing through a ring-shaped rectifying member located downstream of the annular flow path of the chamber, surrounding the outside of the travel path of the yarn and covering the entire downstream end of the annular flow path of the first buffer chamber And then having an annular flow channel disposed downstream of the ring-shaped rectifying member so as to surround the outside of the travel path of the yarn, the ring-shaped rectifying member on the first buffer chamber side of the ring-shaped rectifying member Larger than the cross-sectional area of the channel in the cross section perpendicular to the yarn travel path To the second buffer chamber having a large cross-sectional area, and then the air flow is directed inward from an annular rectifying filter disposed inside the second buffer chamber so as to surround the outside of the traveling path of the yarn. A melt spinning method characterized by blowing is provided.

  In the present invention, the “outer diameter of the second buffer chamber” refers to an outer diameter in a cross section perpendicular to the yarn traveling path of the annular flow path of the second buffer chamber.

  In the present invention, the “inner diameter of the second buffer chamber” refers to an inner diameter in a cross section perpendicular to the yarn traveling path of the annular flow path of the second buffer chamber.

  In the present invention, the “yarn traveling route” refers to a main route through which a thermoplastic polymer is melt-spun from an upper spinneret and the spun yarn is wound downward. Here, “upward” means the side close to the spinneret in the traveling direction of the main yarn from which the thermoplastic polymer is melt-spun from the spinneret and the spun yarn is wound, and is wound around the yarn. The side to be taken is called “downward”.

  In the present invention, the “net buffer flow path length of the first buffer chamber” is a portion in the annular flow path of the first buffer chamber where airflow does not enter or exit from the flow path in a direction perpendicular to the yarn traveling direction. The length of the yarn running direction.

  According to the annular cooling device for spinning and the melt spinning method of the present invention, as described above, there is no contact or fusion of the yarn by excellent circumferential air velocity uniformity of the airflow blown out from the spinning annular cooling device. Further, a multifilament yarn having excellent quality such as unevenness of yarn thickness and strength / elongation can be obtained with good yarn production and operability.

  Hereinafter, the best embodiment of the spinning annular cooling device and the melt spinning method of the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic cross-sectional view of an annular cooling device for spinning used in a typical embodiment of the present invention. FIG. 2 is a view taken along the line AA in FIG. 3 (8) is a schematic longitudinal sectional view of an annular cooling device for spinning used in another embodiment of the present invention, and FIG. 14 is a schematic longitudinal sectional view of a melt spinning device used in a typical embodiment of the present invention. FIG.

  The melt spinning apparatus used in a typical embodiment of the present invention includes a spinneret 23, an annular cooling apparatus for spinning according to the present invention, an oil agent application apparatus 35, take-up rollers 36 and 37, and a winding apparatus 38. In FIG. 14, the yarn 22 spun from the spinneret 23 is cooled by an air flow blown from the spinning annular cooling device of the present invention, and after the oil agent is applied by the oil agent applying device 35, the take-up roller 36, It is wound up by 37 and wound as a package 39 by the winding device 38. In the above-described apparatus, the spinning annular cooling device used in the representative embodiment of the present invention includes the airflow introduction pipe 20, the airflow supply port 1 connected from the airflow introduction pipe 20, and the airflow supply port 1 from the lateral direction. A first buffer chamber 13 which is connected and disposed so as to surround the outside of the yarn traveling path, and has an annular flow path sandwiched between the first buffer outer wall surface 14 and the inner wall surface 16; A ring-shaped rectifying member 11 positioned downstream of the buffer chamber 13 so as to cover the entire downstream end of the annular flow path, and surrounds the outside of the yarn travel path downstream of the ring-shaped rectifying member 11 And has an annular flow path sandwiched between the outer wall surface 15 of the second buffer chamber and the rectifying filter 5, and is perpendicular to the yarn traveling path on the first buffer chamber 13 side of the ring-shaped rectifying member 11. Has a cross-sectional area larger than the channel cross-sectional area in the cross-section A second buffer chamber 12, a cylindrical rectifying member 10 for partitioning the second buffer chamber 12 in and out of a concentric circle, and an air flow disposed inside the second buffer chamber 12 so as to surround the outside of the yarn traveling path. It is comprised from the cyclic | annular rectification filter 5 with the flow path which blows out inward. In that case, the length of the yarn in the travel path direction downstream of the ring-shaped rectifying member 11, that is, the second buffer chamber 12 side, is in the range of 0 to 10 mm from the ring-shaped rectifying member 11 toward the downstream side. The cross-sectional area of the flow path perpendicular to the traveling path is 0 upstream from the ring-shaped rectifying member 11, that is, the length in the traveling path direction of the yarn on the first buffer chamber 13 side is 0 toward the upstream side from the ring-shaped rectifying member 11. It is preferable to make it larger than the cross-sectional area of the channel perpendicular to the running path of the yarn in the range of ˜70 mm.

  As another embodiment, as shown in FIG. 3 (7), the second buffer chamber 12 includes an annular channel sandwiched between the second buffer chamber outer wall surface 15 and the rectifying filter 5, and the second buffer chamber outer wall surface 15. It is composed of an annular flow path sandwiched from the wall surface 16, and by providing a step on the inner wall surface 16, the flow path cross-sectional area perpendicular to the running path of the yarn disposed downstream of the ring-shaped rectifying member 11 is widened. May be.

  As another embodiment, as shown in FIG. 3 (6), with respect to the channel cross-sectional area perpendicular to the yarn traveling path of the upstream first buffer chamber 13 via the ring-shaped rectifying member 11. If the cross-sectional area of the flow path perpendicular to the yarn travel path in the second buffer chamber 12 on the downstream side is widened, the flow path perpendicular to the thread travel path in the space above the second buffer chamber 12 You may be comprised from several buffer space which cross-sectional area reduces toward upper direction. Alternatively, it may be composed of a plurality of buffer spaces whose flow path cross-sectional area perpendicular to the yarn travel path increases or decreases upward, and further, the flow path cross-sectional area perpendicular to the thread travel path is It may be composed of a buffer space that continuously decreases or increases upward. However, in this case, the air flow flowing upward is once rectified by making the flow passage cross-sectional area perpendicular to the yarn path in the uppermost buffer space equal to the upper flow passage. Is preferred. Here, the side channel cross-sectional shape of the first buffer chamber 13 and the second buffer chamber 12 is not limited to a rectangle or a trapezoid, but is a triangle, a pentagon, a polygon, a semicircle, or a semielliptical shape. The shape is not particularly limited as long as the shape in the cross section perpendicular to the traveling path of the yarn is a double circle.

  The ring-shaped rectifying member 11 of the present embodiment has a structure that can be easily attached and detached, and is provided with a guide groove on the inner wall surface 16 or the first buffer outer wall surface 14 or both, and is fixed with a bolt or the like. . The ring-shaped rectifying member 11 is preferably a ring-shaped integrally formed product in consideration of airflow rectifying effects and workability such as attachment / detachment. However, the ring-shaped rectifying member 11 may be formed into a ring shape by combining several meniscus shapes. There is no problem. In the present embodiment, the ring-shaped rectifying member 11 is a porous member, and it is most preferable to use a punching metal having a flow path opening ratio of 15 to 60% in order to obtain a rectifying effect. The ring-shaped rectifying member 11 may be a laminated structure having a slit channel, may be a porous ceramic, may be a wire mesh, or may be a honeycomb structure. Further, as shown in FIG. 3 (8), as an alternative to the ring-shaped rectifying member 11, the channel width on the side opposite to the airflow supply side 2 is narrow and the channel width on the airflow supply port 1 is wide. An eccentric ring 21 may be attached. In that case, it has the same effect as the ring-shaped rectifying member 11 that reduces the pressure imbalance in the circumferential direction by suppressing an increase in the wind speed on the anti-airflow supply side 2. The eccentric ring 21 and the ring-shaped rectifying member 11 may be used in combination, or a plurality of them may be stacked. However, the uniform wind speed variation in the circumferential direction by adjusting the flow path width using the eccentric ring 21 has a large influence of the wind speed distribution on the flow path width dimension, and is sufficient to find the optimum dimensions according to various spinning conditions. Consideration may be required.

  Here, the rectifying effect of the ring-shaped rectifying member 11 is that the flow path is rapidly reduced and then greatly widened to form a minute turbulent state in a minute space and mix to equalize the wind speed difference of the airflow. It becomes possible. Therefore, as shown in FIG. 3 (2) as another embodiment, the ring-shaped rectifying member 11 has two or more multi-stage configurations with a constant interval, for example, an interval of 10 to 50 mm. The rectifying effect can be obtained. Furthermore, as an advantage of the multi-stage configuration, even if the channel opening ratio is set to be somewhat large, the same rectifying effect as that of the single configuration ring-shaped rectifying member 11 can be obtained. Operability can be improved. The flow rate of the ring-shaped rectifying member 11 is 30% to 60% of the flow path cross-sectional area of the second buffer chamber space on the airflow inflow side, so that the rectifying effect can be achieved efficiently. When the flow passage opening ratio of the ring-shaped rectifying member 11 is 60% or more, there is no sudden shrinkage of the flow passage, and it is difficult to obtain a uniform airflow effect due to the sudden shrinkage and widening of the flow passage. When the ratio is 30% or less, the rapid shrinkage of the flow path is too large, and air flow turbulence occurs on the downstream side of the ring-shaped rectifying member 11, making it difficult to achieve uniform wind speed. Furthermore, when the flow path opening ratio is 30% or less, clogging with the flow straightening member is likely to occur during long-term continuous use, and productivity, operability, and the like become problems.

  As described above, in order to obtain the rectifying effect of the ring-shaped rectifying member 11, it is necessary to determine selection of the ring-shaped rectifying member, selection of the channel opening ratio, selection of the number of sheets, selection of the interval, and the like. At that time, as described in Non-Patent Document 1, if the setting of the resistance coefficient using the ring-shaped rectifying member 11 is mistaken, the disturbance increases, the rectifying effect cannot be obtained, and the wind speed spots are deteriorated. In particular, since the air volume greatly affects the resistance coefficient, it is very difficult to optimize the configuration of the ring-shaped rectifying member 11 under various spinning conditions.

  Therefore, the arrangement of the ring-shaped rectifying member 11 is important as a means for achieving the rectifying effect most efficiently. In other words, the second flow passage disposed on the downstream side with respect to the flow path cross-sectional area perpendicular to the yarn traveling path of the first buffer chamber 13 disposed on the upstream side via the ring-shaped rectifying member 11. By widening the cross-sectional area of the flow path perpendicular to the yarn running path in the buffer chamber 12, the rectifying effect of the ring-shaped rectifying member 11 can be further enhanced. At that time, if the ring-shaped rectifying member 11 has a multi-stage configuration, the flow passage cross-sectional area perpendicular to the yarn traveling path as described above may be widened with respect to the ring-shaped rectifying member 11 in each stage. Although it is good, it is preferable to widen the ring-shaped straightening member on the most downstream side.

  As described above, as the structure that widens the cross-sectional area of the flow path perpendicular to the running direction of the yarn of this embodiment, it is most preferable as a rectifying effect to rapidly widen in a staircase shape, You may widen gradually so that an area may become large. When the channel cross-sectional area is gradually widened, the total length of the channel cross-sectional area amplification section is preferably set within a range of 50 mm or more upward in the running direction of the yarn.

  Next, the widening ratio of the channel cross-sectional area perpendicular to the running direction of the yarn via the ring-shaped rectifying member 11 of the present embodiment (ratio of the channel cross-sectional areas of the first buffer chamber and the second buffer chamber) is 1 It is good to set it in the range of 1 to 5 times. If the widening ratio is 1.1 times or less, the above rectifying effect cannot be obtained. In order to increase the widening ratio by 5 times or more, the flow passage cross-sectional area perpendicular to the yarn traveling path of the first buffer chamber 13 disposed on the upstream side of the ring-shaped rectifying member 11 is extremely small, or the ring shape It is necessary to extremely increase the flow path cross-sectional area perpendicular to the yarn traveling path of the second buffer chamber 12 disposed on the downstream side of the rectifying member 11. Therefore, if the cross-sectional area perpendicular to the travel path of the yarn disposed on the upstream side of the ring-shaped rectifying member 11 is made extremely small, circumferential wind speed spots due to rapid contraction of the flow path occur. Furthermore, since the volume space of the first buffer chamber 13 is minimized, the pressure equalizing effect is hindered and airflow turbulence occurs. Further, if the flow path cross-sectional area perpendicular to the traveling path of the yarn disposed downstream of the ring-shaped rectifying member 11 is extremely increased, the apparatus becomes larger as the outer diameter of the second buffer chamber 12 increases, and the size of the apparatus increases. In the spindle-type annular cooling device for spinning, there is a problem in workability and operability due to restrictions on the pitch between the caps. Furthermore, it is necessary to widen the production space, which increases capital investment and is not desirable in terms of production cost. Further, the inner diameter of the second buffer chamber 12 is reduced, that is, for spinning, in order to extremely increase the flow path cross-sectional area perpendicular to the traveling path of the yarn disposed on the downstream side of the ring-shaped rectifying member 11. Since the diameter of the annular cooling cylinder is reduced, when manufacturing multifilament yarns, there is a problem in that the distance between the yarns is close, contact and fusion occur, the yarn property unevenness deteriorates, and the yarn production property is poor. appear.

  Next, the cylindrical rectifying member 10 has a structure that can be easily attached and detached, and is provided with a guide groove on the upper support 17 or the lower support 18 or both, and is fixed with a bolt or the like. It may be sandwiched between the upper and lower supports, and may be fixed to the upper support 17 or the lower support 18 by welding.

  The cylindrical rectifying member 10 of the present embodiment is a porous member, and punching metal having a channel opening ratio of 20 to 60% is most suitable for obtaining the rectifying effect of the passing airflow. It may be a laminated structure, a porous ceramic, a wire mesh, or a honeycomb structure. The length of the cylindrical rectifying member 10 in the running direction of the yarn is preferably equal to the length of the rectifying filter 5 in order to obtain a rectifying effect over the entire length of the rectifying filter 5, or larger than the total length of the rectifying filter 5. It is preferable to set the length to include the rectifying filter 5. In that case, the structure in which the cylindrical rectifying member 10 is connected to the lower support 18 is most preferable, but it may be cut off at the end of the space of the second buffer chamber. As another embodiment, as shown in FIG. 3 (3), the cylindrical rectifying member 10 may have two or more multistage configurations having different cylindrical outer diameters. The multi-stage configuration makes it easy to obtain a rectifying effect as described in the ring-shaped rectifying member 11 described above, and further has an advantage that the wind speed distribution in the yarn traveling direction can be controlled. Moreover, the case where the cylindrical rectification | straightening member 10 is not arrange | positioned like FIG. 3 (1) may be sufficient, and FIG. 3 (2), FIG. 3 (3), FIG. 3 (5), FIG. (7) In the device configuration of FIG. 3 (8), the cylindrical rectifying member 10 may not be disposed.

  Next, the rectifying filter 5 has a porous structure in which an airflow outlet is opened in a central direction toward the yarn traveling path, and a hole inclined downward from a direction perpendicular to the yarn traveling direction is formed. It is a member. The airflow is rectified by the rectifying filter 5, and an airflow inclined downward from a direction perpendicular to the yarn traveling direction is formed. The shape of the hole may be a circle, trapezoid, octagon or hexagon, and is an array of holes inclined from the inner diameter to the outer diameter by 5 to 20 degrees over the entire surface. As a porous member in which inclined holes are formed, a porous member obtained by thermosetting and molding a cellulose ribbon in a spiral shape can be raised. This porous member is formed by impregnating a cellulose ribbon (material: paper) with a thermosetting resin (phenolic resin) and then heat-curing to form a gap (pore: about 40 μm) in the ribbon layer. The gaps are uniformly distributed from the outer peripheral side toward the center. And when winding this cellulose ribbon helically, it becomes a structure where a clearance gap inclines toward a center by inclining and winding. Further, the porous member may be a high-temperature compression-molded metal particle or metal fiber, or a multi-layer structure in which an annular ring having fine slit grooves is formed from the outside toward the center direction, and a high-temperature compression-molded laminated structure. It may be a body. The material of these porous members is suitably made of paper, wood, synthetic resin, or metal having an appropriate rigidity.

  The length of the rectifying filter 5 in the running direction of the yarn includes the maximum thinning deformation position at which the multifilament yarn changes most rapidly, and the length including the cooling and solidifying position of the yarn is the thickness variation of the yarn. This is a preferred form for suppression. When the circumferential wind speed unevenness of the airflow is poor, a difference occurs in the yarn traveling direction between the maximum thinning deformation position of the yarn and the cooling and solidifying position. In particular, the cooling length, that is, the length of the rectifying filter 5 needs to be lengthened to the extent that a significant difference occurs at the cooling and solidifying position. However, if the circumferential wind speed spot is good, the length of the rectifying filter 5 is appropriate. It becomes possible to make it long. Therefore, the length of the rectifying filter 5 of the present embodiment is preferably 50 to 500 mm, and more preferably 100 to 300 mm. Further, the thickness of the rectifying filter 5 is preferably 1 to 20 mm, more preferably 5 to 10 mm, as a thickness that can sufficiently rectify the airflow passing through the slit flow path.

Further, rubber, silicon, and packing made of “Teflon (registered trademark)” 19a and 19b are attached to the contact surfaces of the rectifying filter 5 with the upper support 17 and the lower support 18 in order to maintain airtightness. Good. Furthermore, by applying a spring expansion / contraction structure to the lower support 18 and constantly applying a surface pressure to the upper and lower seal surfaces of the rectifying filter 5, thermal creep deformation of the packings 19a and 19b, air internal pressure fluctuations, or the rectifying filter 5 It can cope with thermal dimensional changes and dimensional changes over time, and can keep airtightness stably and continuously.
Next, the flow state of the airflow in the spinning annular cooling device of the present embodiment will be described with reference to FIGS. FIG. 2 is an AA arrow view of FIG. In the spinning annular cooling device of the present embodiment, the air flow introduction pipe 20 is connected from the lateral direction to the first buffer chamber 13 having an annular flow channel because of the device configuration for supplying the air flow from the outside. As shown in FIG. 2, the airflow introduction pipe 20 opens radially toward the first buffer chamber 13, and the airflow directly collides with the inner wall surface 16 by making the flowpath a cross-sectional area slightly increased. , The pressure in the first buffer chamber 13 is equalized, and circumferential wind speed spots of the airflow blown out from the rectifying filter 5 can be reduced. Therefore, in the airflow introduction pipe 20, the airflow supplied from the outside is collided with the baffle plate 7, and the airflow VA in which the wind speed spots are once reduced and made uniform is formed. Therefore, first, the air flow VA flows into the first buffer chamber 13 from the air flow supply port 1 and flows in the circumferential direction through the annular flow path along the first buffer outer wall surface 14 to the counter air flow supply side 2. Then, the air flow VU is sequentially turned upward to form the air flow VU toward the ring-shaped rectifying member 11. Here, since the air flow VR and the air flow VU are mixed in the first buffer chamber 13, it is extremely difficult to simultaneously rectify the air flow VR and the air flow VU. Therefore, in order to complete the direction change of the airflow VR to the airflow VU, the necessary buffer space can be obtained by arranging the ring-shaped rectifying member 11 above the upper end 26 of the airflow supply port. At that time, the ring-shaped rectifying member 11 is preferably disposed in the range of 3 mm to 80 mm of the net buffer flow path length of the first buffer chamber, and the ring-shaped rectifying member 11 is disposed at a position of 3 mm or more. By allowing the airflow VU that has sufficiently changed the direction of the airflow VR to pass through the ring-shaped rectifying member 11, the pressure imbalance in the circumferential direction can be reduced, and the circumferential wind speed spots of the airflow VU can be reduced. Further, by setting the net buffer flow path length of the first buffer chamber to 80 mm or less, the height of the spinning annular cooling device can be reduced, and the productivity can be improved. On the other hand, when the length is 80 mm or more, the spinning annular cooling device needs to be enlarged and the production space needs to be widened, which increases capital investment and is not desirable in terms of production cost.

  Next, after improving the rectifying property of the air flow VU by passing through the ring-shaped rectifying member 11, the air flow VU flowing above the second buffer chamber 12 forms the air flow VU flowing continuously upward. At the same time, since the airflow VS is divided into the airflow VS flowing in the center direction of the filamentous travel path, the airflow of the airflow VU gradually decreases in the upward direction. In that case, when the cylindrical rectification member 10 is provided, it has the function of changing the direction of the airflow VU to the airflow VS by passing through the cylindrical rectification member 10. Then, the air flow VS flowing in the center direction in the second buffer chamber 12 is formed by mixing and forming a minute turbulence state in a minute space by sharply reducing the flow path of the cylindrical rectifying member 10 and then widening it greatly. The difference in wind speed of the airflow can be reduced. At this time, by increasing the cylindrical diameter of the cylindrical rectifying member 10 and bringing the cylindrical rectifying member 10 close to the outer wall surface 15 of the second buffer chamber, the annular volume space sandwiched between the cylindrical rectifying member 10 and the rectifying filter 5 increases. The rectification effect due to the reduction and widening of the image can be easily obtained. Therefore, in order to achieve uniform circumferential wind speed of the airflow blown inward from the rectifying filter 5, continuous rectification of the airflow VR, the airflow VU, and the airflow VS passing through the spinning annular cooling device is achieved. This is very important.

Here, the air flow VU passing upward through the annular flow path of the second buffer chamber will be described in detail. In order to achieve uniform circumferential wind speed of the airflow blown from the rectifying filter 5, the occurrence of circumferential wind speed spots of the airflow VU in the second buffer chamber 12 is suppressed, and as a result, the circumference of the airflow VS is reduced. It is important to reduce directional wind speed spots. For this purpose, by _setting the outer diameter D _2OUT (m) of the second buffer chamber and the inner diameter D _2INN (m) of the second buffer chamber within the range of the following equation (2), the circumferential wind speed of the air flow VS Spots can be reduced, and uniform wind speed in the circumferential direction from the rectifying filter 5 can be achieved.
0.09 ≦ D _2OUT ≦ 0.3 (m)
D _2INN / D _2OUT ≦ 0.95 (2)
Therefore, when the outer diameter D _2OUT (m) ≧ 0.3 m of the second buffer chamber, the outer diameter of the spinning annular cooling device is increased. Due to the restrictions, workability and operability are problematic. Furthermore, it is necessary to widen the production space, which increases capital investment and is not desirable in terms of production cost.

When the outer diameter D _2OUT (m) ≦ 0.09 m of the second buffer chamber, the inner diameter D _2INN (m) of the second buffer chamber is 0.0855 m or less from Equation (2). Therefore, when the thickness of the rectifying filter 5 is 0.001 m (the minimum usable thickness of the rectifying filter 5), the inner diameter of the air flow blowing portion of the rectifying filter 5 is 0.0853 m. Here, when producing a multifilament yarn, in order to obtain a good yarn forming property with good yarn thickness unevenness and no yarn breakage or the like, a base hole orientation PCD outer diameter of 0.0700 m or more is required. It has been elucidated by the present inventors. Therefore, as described above, when the inner diameter dimension of the rectifying filter 5 is 0.0853 m or less, the rectifying filter 5 and the yarn are too close to each other, resulting in increased yarn swaying, contact / fusion, and yarn property spots. The problem worsens and results in poor yarn production.

_{Further, in} the case of 0.95 ≦ D _2INN / D _2OUT , the flow path upward of the second buffer chamber 13 becomes too narrow, and the wind speed spots in the circumferential direction of the air flow VU deteriorate. Furthermore, since the air velocity VU increases due to the sudden contraction of the flow path, and the air flow VU collides with the upper support 17, the air flow blown inward from the rectifying filter 5 is the upper end of the rectifying filter 5 (close to the spinneret). The wind speed distribution has a wind speed maximum peak value in the vicinity and decreases toward the lower end (winding side). As described above, in the distribution having the maximum wind speed peak value in the vicinity of the upper end of the rectifying filter 5, the wind speed at the upper end of the rectifying filter 5 is fast in the low tension state immediately before the yarn 22 spun from the spinneret 23 is cooled and solidified. For this reason, contact and fusion are likely to occur due to yarn swaying, resulting in deterioration of the thread property spots.

Then, as described in Non-Patent Document 2, the formula (3), the sum of the outer diameter _{D 2OUT} (m) and the second buffer chamber inner diameter _{D 2INN} (m) of the second buffer chamber 12, the cooling air This is a product of the supplied air volume Q (m ³ / sec) and the air dynamic viscosity coefficient ν (m ² / sec), and represents the Reynolds number RE _VU2 of the air flow VU in the annular channel of the second buffer chamber 12. .

RE _VU2 = 4Q / {πν (D _2OUT + D _2INN )} (3)
Where RE _VU2 : Reynolds number of the air flow VU passing through the second buffer chamber,
Q: Cooling air supply air volume (m ³ / sec), ν: Kinematic viscosity coefficient of air stream (m ² / sec),
D _2OUT : the outer diameter (m) of the second buffer chamber,
D _2INN : _Indicates the inner diameter (m) of the second buffer chamber.

If the Reynolds number RE _VU2 of the air flow VU is low in the flow in the flow path of the second buffer chamber 12, the air flow becomes a laminar flow and forms a stable flow. However, the circumferential wind speed spots of the airflow VU are deteriorated, and the circumferential wind speed spots of the airflow finally blown out from the rectifying filter 5 are deteriorated. The critical Reynolds number RE _C is a boundary of the laminar flow and turbulent flow, to be approximately 5.0 × 10 ³ longitudinal disclosed in Non-Patent Document 2.

Therefore, in was elucidated by the present inventors, the Reynolds number _{RE VU2} airflow VU is a range sandwiching the critical Reynolds number RE _C above, and _{^{2.5 × 10 2 ≦ RE VU2 ≦}} 4.5 × 10 4 It is good for the reduction of circumferential wind speed spots to make the range of 1.9 × 10 ³ ≦ RE _VU2 ≦ 1.1 × 10 ⁵ , more preferably, the outer diameter D _2OUT of the second buffer chamber 12. The supply air volume Q that satisfies the above range can be selected in accordance with the inner diameter _D2INN of the second buffer chamber 12.

  Next, the yarn cooling effected by the flow form of the airflow blown inward from the rectifying filter 5 will be described with reference to FIG. FIG. 4 is a schematic view showing the flow form of the airflow blown out from the spinning annular cooling device used in the preferred embodiment of the present invention. When the multifilament yarn 22 having a single yarn fineness of 0.1 to 1.6 dtex or less and a filament number of 2000 or less is spun, the yarn is cooled and solidified very rapidly, and the yarn accompanying flow VZ accompanying the thinning behavior is generated. It starts from directly under the spinneret 23. When these multifilament yarns 22 are cooled using an annular cooling device for spinning, an accompanying flow of yarn is generated from the upper portion of the annular cooling device for spinning, and a large amount of air flows in the running direction of the yarn. In the vicinity immediately below, a kind of vacuum state in which air is insufficient is generated, and in order to compensate for the insufficient air, an upward air flow VV is generated at the center of the spinneret 23. In order to suppress these occurrences, the amount of supply air at the upper end of the rectification filter 5 may be increased. However, if the amount of supply air increases, the heat retaining property of the spinneret 23 deteriorates, and in particular, the rectification starts from the surface of the spinneret 23. In the multifilament yarn 22 in which it is necessary to shorten the airflow blowing start distance (hereinafter referred to as the cooling start distance QTD) at the upper end of the filter 5, the influence becomes remarkable, yarn breakage occurs frequently, and the yarn-making property deteriorates. Therefore, in order to efficiently cool the spun multifilament yarn 22 with the necessary minimum, it is necessary to provide the necessary wind speed and air volume according to the thinning and solidification of the yarn in the yarn traveling direction. Therefore, in the annular cooling device for spinning according to the present embodiment, the circumferential wind speed spots of the blown airflow are eliminated, and an appropriate air volume can be imparted for cooling and solidifying the yarn, so that the circumferential wind speed spots of the updraft VZ are reduced. Therefore, the surface temperature unevenness of the spinneret 23 is eliminated, and therefore the fineness unevenness can be reduced. Further, since the surface temperature unevenness of the spinneret 23 is eliminated, the cooling start distance QTD can be shortened, so that the yarn forming property when producing the multifilament yarn is stabilized, and a yarn having good yarn physical property unevenness can be obtained.

  Here, the type of airflow is most preferably air that can be easily and regularly used, but it may be a water-soluble gas that is lighter than air, such as ammonia, or a water-soluble gas that is heavier than air, such as hydrogen chloride. Alternatively, it may be a water-insoluble gas such as nitrogen, oxygen, hydrogen, natural gas such as methane, ethane, propane, or butane, or may be humidified steam. .

  The temperature of the airflow is preferably adjusted in the range of 10 to 35 ° C., but considering the energy efficiency, the atmosphere in the building may be given without special control. The airflow may be an airflow heated by a heater built in the spinning annular cooling device, or may be an airflow heated by an external heating means, and is composed of a thermoplastic polymer or a thermoplastic polymer. What is necessary is just to set arbitrarily according to the characteristics, required quality, etc. of multifilament yarn.

  This embodiment is suitable for all the multifilament yarns obtained by the annular cooling device for spinning and the melt spinning method. Therefore, it is not particularly limited by the thermoplastic polymer constituting the multifilament yarn. For example, examples of the thermoplastic polymer constituting the multifilament yarn suitable for this embodiment include polyester, polyamide, polyphenylene sulfide, polyolefin, polyethylene, polypropylene, and the like.

  An example of a polyester suitable for this embodiment is, for example, a thermoplastic polymer synthesized from a dicarboxylic acid or an ester-forming derivative thereof and a diol or an ester-forming derivative thereof, as a molded article such as a fiber, a film, or a bottle. The thing which can be used is mentioned. Specific examples of the polyester include, for example, polyethylene terephthalate, polytrimethylene terephthalate, polybutylene terephthalate, polylactic acid, polyethylene naphthalate, polybutylene naphthalate, polypropylene terephthalate, polytetramethylene terephthalate, polyethylene-2, 6- Naphthalenedicarboxylate, polyethylene-1,2-bis (2-chlorophenoxy) ethane-4,4'-dicarboxylate, and the like. In the above, polyethylene terephthalate is the most versatile, but this embodiment is also suitable for polyethylene terephthalate or polyester copolymers mainly containing ethylene terephthalate units. In addition, various ester-forming derivatives may be copolymerized within a range that does not impair the spinning stability. For example, in a polyester cation dyeable yarn capable of being dyed with excellent sharpness, an ester-forming derivative having a sodium sulfonate group is generally 10 mol% or less as long as the yarn-making stability is not impaired. Although copolymerized, such a thing may be sufficient.

  Examples of polyamides suitable for this embodiment include nylon 6, nylon 66, and the like. This embodiment is also suitable for nylon 6 and nylon 66.

  In addition, this embodiment is also suitable for a cellulose ester-based thermoplastic polymer containing a plasticizer. Cellulose ester refers to those in which the hydroxyl group of cellulose is blocked by an ester bond, and specific examples include esters with carboxylic acids such as cellulose acetate, cellulose acetate propionate, cellulose acetate butyrate, and cellulose acetate phthalate. It may have a bond, may have an ester bond with oxylcarboxylic acid such as lactic acid, glycolic acid, hydroxy acid or a polymer thereof, caprolactone, propiolactone, valerolactone, pivalolactone, etc. It may be a cyclic ester or an ester thereof with a polymer thereof, or a mixed ester thereof. These celluloses may contain a plasticizer. Specific examples of the plasticizer include, for example, polyethylene glycol, polypropylene glycol, and polybutylene having a weight average molecular weight of 200 to 4000 as those having a relatively low molecular weight. Polyalkylene glycol compounds such as glycol, polyhydric alcohol compounds such as glycerin compounds and caprolactam compounds, dimethyl phthalate, diethyl phthalate, dihexyl phthalate, dioctyl phthalate, dimethoxyethyl phthalate, ethyl phthalyl ethyl glucoat, butyl phthalyl butyl Phthalic acid esters such as glycate, aromatic polycarboxylic acid esters such as tetraoctyl pyromellitate, trioctyl trimellitate, dibutyl adipate, dioctyl adipate, Aliphatic polycarboxylic acid esters such as butyl sebacate, dioctyl sebacate, diethyl azate, dibutyl azate, dioctyl azate, lower fatty acid esters of polyhydric alcohols such as glycerin triacetate and diglycerin tetraacetate, triethyl phosphate, tributyl Examples thereof include phosphate esters such as phosphate, tributoxyethyl phosphate and tricresyl phosphate. Specific examples of the plasticizer include, for example, aliphatic polyesters composed of glycol and dibasic acid such as polyethylene adipate, polybutylene adipate, polyethylene succinate, polybutylene succinate, and the like having a relatively high molecular weight. And aliphatic polyesters composed of oxycarboxylic acids such as polylactic acid and polyglycolic acid, aliphatic polyesters composed of lactones such as polycaprolactone, polypropiolactone and polyvalerolactone, and vinyl polymers such as polyvinylpyrrolidone. These plasticizers can be used alone or in combination.

  Furthermore, in the above-mentioned thermoplastic polymer, within a range not impairing the yarn production stability, matting agent such as titanium dioxide, silicon oxide, kaolin, anti-coloring agent, stabilizer, antioxidant, deodorant, flame retardant, Various functional particles such as yarn friction reducing agents, color pigments, surface modifiers, and additives such as organic compounds may be contained, and copolymerization may be included.

  In addition, the thermoplastic polymer used in the present embodiment may be composed of a single component or a plurality of components. In the case of a plurality of components, for example, a configuration such as a core sheath, side-by-side, etc. may be mentioned. . In addition, the cross-sectional shape of the multifilament yarn may be an irregular shape such as a circle, a triangle, a flat shape, or a hollow shape.

  This embodiment is suitable for all the multifilament yarns obtained by the annular cooling device for spinning and the melt spinning method. Therefore, it is not particularly limited by the single yarn fineness of the multifilament yarn. For example, the single yarn fineness before winding or when wound without being drawn, or the single yarn fineness after drawing or drawing / false twisting may be in the range of 0.1 to 10 dtex. Moreover, the range of 0.2-3.2 dtex may be sufficient as the single yarn fineness after extending | stretching or extending | stretching and false twisting. The smaller the single yarn fineness, the clearer the difference from the prior art.

  This embodiment is suitable for all the multifilament yarns obtained by the annular cooling device for spinning and the melt spinning method. Therefore, it is not particularly limited by the number of single filaments of the multifilament yarn. For example, the number of single filaments of the multifilament yarn may be in the range of 30 to 2000. The number of single filaments of the multifilament yarn may be in the range of 30 to 600. The greater the number of single filaments of the multifilament yarn, the clearer the difference from the prior art.

Each characteristic value used in the examples was determined by the following measurement method.
(1) Thread thickness spots, Wooster spots [H]:
Using a USTER TESTER UT-4 (trade name) manufactured by ZELLWEGER USTER, measured for 5 minutes at a yarn speed of 100 m / min, a supply tension of 1/30 g / dtex, and a twister rotation speed of 8000 rpm, Wooster spots U% evaluated by HInert [% H]: “less than 0.4” ◎, “0.4 or more and less than 0.6” ○, “0.6 or more and less than 1.0” Δ, “1.0 or more” × × It was evaluated as a patch.
(2) Strength / Elongation / Strong Elongation Product Using a TENSILON RTC-1210A (trade name) manufactured by ORIENTEC, a test length of 200 mm arbitrarily cut from the manufactured yarn (multifilament yarn) was used, and a tensile speed of 200 mm / The strength / elongation measured in minutes was obtained from the following formula as the strong elongation product.

Strong elongation product = strength (cN / dtex) × (elongation (%)) ^1/2
(3) Airflow blowout wind speed:
As for the blowing speed of the air current, an anemo master anemometer (Nippon Kanomax Co., Ltd .: MODEL6004 (trade name)) or Cambridge Accusense anemometer (Degree Controls Inc .: UAS1100PC (trade name)) is used at room temperature and normal humidity. Using, the probe of the anemometer was installed in a gap of 5 mm to 10 mm from the inner peripheral surface of the rectifying filter 5 toward the center and measured.
(4) Circumferential wind velocity unevenness, circumferential wind velocity non-uniformity:
Circumferential wind velocity spots are the airflow blown air velocity at the rectifying filter 5 in a room temperature / humidity room, with the airflow supply port 1 being 0 degrees in the circumferential direction, 8 points in 45 degree increments, the yarn traveling direction 3 points, 8 points x 3 points = 24 points from the top of the rectifying filter 5 as 10 mm position, 30 mm position and 50 mm position (Equation [1] to [3] below), and the circumference at each height position The average value of the directional wind speed values of 8 points is calculated (the following [4] equation), the variation rate with the measured value is obtained at each height position (the following [5] equation), and the total variation rate (ΔV _10i , ΔV _30i) , ΔV _50i : i = 0 to 315, 45 degrees).
[1] Wind speed at a position 10 mm from the upper end of the rectifying filter 5; V _10i (i = 0 to 315, 45 degrees)
[2] Wind speed at 30 mm position from the upper end of the rectifying filter 5; V _30i (i = 0 to 315, 45 degrees)
[3] Wind speed 50 mm from the upper end of the rectifying filter 5; V _50i (i = 0 to 315, 45 degrees)
[4] Average wind speed at positions 10, 30, and 50 mm from the upper end of the rectifying filter 5:
V _10ave = (Sum (V _10i )) / 8
V _30ave = (Sum (V _30i )) / 8
V _50ave = (Sum (V _50i )) / 8 (i = 0 to 315, 45 degrees)
[5] Wind speed fluctuation rate from the average wind speed at positions 10, 30, and 50 mm from the upper end of the rectifying filter 5;
ΔV _10i = (V _10i −V _10ave ) / V _10ave
ΔV _30i = (V _30j −V _30ave ) / V _30ave
ΔV _50i = (V _50j −V _50ave ) / V _50ave (i = 0 to 315, 45 degrees)
(5) Spinnability:
Execute spinning for 36 hours with 36 spindles, and evaluate the number of breaks during this period. ◎ "less than 1" is ◎, "1 to less than 2" is ◯, "2 to less than 3" Δ, “3 times or more” was evaluated as x.
(6) Airflow supply air volume:
The air flow rate Q (m ³ / sec) to the spinning annular cooling device is set at an inlet air flow meter 1 at the inlet of the air flow feeding port 1 of the spinning annular cooling device in a room at normal temperature and humidity. The differential pressure was measured and obtained as the air volume.
[Example 1]
Using thermoplastic polymer (adjusted polymer intrinsic viscosity IV to 0.6-0.7), melt 295 ° C polyethylene terephthalate from spinneret 23 at a single hole discharge rate of 0.27g / min. It cooled using the cyclic | annular cooling apparatus for spinning of a form, and after winding oil agent at the speed | rate of 2500 m / min after oil agent provision with the oil agent provision apparatus 35, extending | stretching and false twisting were implemented and the multifilament yarn was manufactured. At that time, the distance from the lower surface of the spinneret 23 to the cooling start position of the yarn 22 (cooling start distance QTD) was 23 mm. As shown in FIG. 1, the annular cooling device for spinning of the present embodiment includes a first buffer chamber 13 and a second buffer chamber 12, and on the boundary surface between the first buffer chamber 13 and the second buffer chamber 12. A punching metal having an aperture ratio of 40.3% (hole diameter 2 mm, pitch 3 mm, staggered arrangement, plate thickness 1.5 mm) was arranged as the ring-shaped rectifying member 11. The first buffer chamber 13 has an inner diameter of 130 mm (matches the inner wall surface 16), the first buffer chamber 13 has an outer diameter of 170 mm, the second buffer chamber 12 has an outer diameter of 170 mm, and the second buffer chamber 12 has an inner diameter of 109.6 mm (the rectifying filter 5). A cylindrical rectifying member in which a punching metal having an aperture ratio of 40.3% (hole diameter 2 mm, pitch 3 mm, staggered arrangement, plate thickness 1.5 mm) is formed in a tube shape in the second buffer chamber 12. 10 (inner diameter 126 mm / outer diameter 129 mm) was disposed. The rectifying filter 5 is a porous member (inner diameter of 97 mm, outer diameter of 109.6 mm, outer diameter of 109.6 mm, spirally wound with a cellulose ribbon (material: paper), impregnated with a thermosetting resin (phenol resin), and then heat-cured. The height was 200 mm, the hole diameter was 40 μm, and the spinning direction was inclined from a right angle to a downward direction by 15 degrees).

56 dtex, 144 filament yarns, and 1 polyester extra-fine fiber were produced using the above-mentioned spinning annular cooling device. At this time, as a result of blowing an air flow at a normal temperature of 20 ° C. from the rectifying filter 5, a circumferential air velocity spot of 4.0% was 43.7 m ³ / hour. At that time, air was used as the airflow. The spinneret 23 has a base diameter of 110 mm, a spinning hole arrangement in a two-row annular arrangement, an outer diameter PCD of 86 mm, and an inner diameter PCD of 76 mm. As shown in Table 1, the best results were obtained for the spinning performance during spinning, and the Worcester spots of the obtained ultrafine fibers gave good results.

[Example 2]
Example 2 will be described as an example in which the fineness is equal to Example 1 and the number of yarns is increased. Using the same spinning annular cooling device as in Example 1, 56 dtex, 288 filament yarns, and two yarns (144 filament yarns per yarn) were produced. At this time, as a result of blowing air from the rectifying filter 5 at a supply air volume of 61.3 m ³ / hour and a room temperature of 20 ° C., the circumferential wind speed spot was 4.0%. Further, the diameter of the spinneret 23 is 110 mm, the spinning holes are arranged in a three-row annular group, the outermost diameter PCD is 86 mm, the PCD 72 mm, the innermost diameter PCD is 58 mm, and four discharge holes per introduction port. As shown in Table 1, a good result was obtained for the spinning performance during spinning, and a good result was obtained for the Worcester patches of the obtained ultrafine fibers.
[Example 3, Example 4]
In the third embodiment, the ring-shaped rectifying member 11 is disposed at a position where the net buffer flow path length of the first buffer chamber 13 is 58.5 mm from the upper end 26 of the air flow supply port, and in the fourth embodiment, the air flow supply port is provided. Circumferential wind speed distribution spots and Worcester spot improvement effects that the ring-shaped rectifying member position 11 has an influence by arranging the net buffer flow path length of 4.5 mm in the first buffer chamber 13 from the upper end 26 upward. It was confirmed. Therefore, using the above-mentioned spinning cooling apparatus for spinning, polyester microfibers of 33 dtex, 144 filament yarns, 2 yarns (72 filament yarns per yarn) were produced. At this time, as a result of blowing air at a normal temperature of 20 degrees with a supply air volume of 49.9 m ³ / hour from the rectifying filter 5, the circumferential wind speed spots were 2.6% in Example 3 and 7 in Example 4. It was 9%. The spinneret 23 has a base diameter of 110 mm, a spinning hole arrangement in a two-row annular arrangement, an outer diameter PCD of 86 mm, and an inner diameter PCD of 76 mm. As shown in Table 1, good results were obtained with respect to the spinnability during spinning and the Worcester spots of the obtained ultrafine fibers. In particular, in the third embodiment, the ring-shaped rectifying member 11 is disposed at the net buffer flow path length of 58.5 mm of the first buffer chamber 13 upward from the air flow supply port upper end 26, so that the first buffer chamber 13 The buffer space was expanded, and as a result, circumferential wind speed spots became the best, leading to better Wooster spots.
[Example 5, Example 6]
Next, Example 5 will be described as an example in which the hole orientation of the spinneret 23 is the same as in Example 4 and the configuration of the same annular cooling device for spinning and the single yarn fineness is large. 84 dtex, 144 filament yarns and 1 yarn polyester ultrafine fiber were produced. At this time, as a result of blowing air having a supply air volume of 61.3 m ³ / hour and a room temperature of 20 ° C. from the rectifying filter 5, the circumferential wind speed spot was 7.5%. As shown in Table 1, good results were obtained with respect to spinning performance during spinning and Worcester spots of the obtained fibers. In addition, Example 6 will be described as an example in which the hole orientation of the spinneret 23 is the same as that of Example 4, the configuration is the same as the annular cooling device for spinning, and the single yarn fineness is large. 167 dtex, 72 filament yarns, 1 yarn polyester fiber were produced. At this time, as a result of blowing air at an air flow rate of 53.2 m ³ / hour and normal temperature of 20 ° C. from the rectifying filter 5, the circumferential wind speed spot was 7.2%. As shown in Table 1, the best results were obtained with respect to the spinning performance during spinning, and the Worcester spots of the obtained fibers gave good results.
[Example 7]
The effect of improving circumferential wind speed distribution spots and Worcester spots was confirmed by the influence of the cylindrical rectifying member. In Example 7, 100 dtex, 144 filament yarns, and two yarns (72 filament yarns per yarn) are excluded from the cylindrical flow straightening member 10 of the annular cooling device for spinning used in Example 1. Polyester fibers were produced. At this time, as a result of blowing air with a supply air volume of 40.6 m ³ / hour from the rectifying filter 5, the circumferential wind speed spot was 6.6%. Further, the spinneret 23 has a base diameter of 100 mm and a spinning hole arrangement in a two-row annular arrangement with an outer diameter PCD of 76 mm and an inner diameter PCD of 72 mm from the outer diameter side. As shown in Table 1, the best results were obtained with respect to the spinning performance during spinning, and the Worcester spots of the obtained fibers gave good results.
[Comparative Example 1]
In the annular cooling device structure for spinning used in Example 1, the inner diameter of the first buffer chamber 13 is 130 mm (matches the inner wall surface 16), the outer diameter of the first buffer chamber 13 is 136 mm, and the outer diameter of the second buffer chamber 12 is 136 mm. The inner diameter of the second buffer chamber 12 is 130 mm (matches the outer diameter of the rectifying filter 5), and the ring-shaped rectifying member 11 is directed upward from the upper end 26 of the air flow supply port to the net buffer flow path length of the first buffer chamber 13. An annular cooling device for spinning, in which the cylindrical rectifying member 10 of the second buffer chamber 12 was removed at the 0 mm position, was used in Comparative Example 1. Other than that, the thermoplastic polymer was melt-spun from the spinneret 23 under the same spinning conditions as in Example 1, wound up after applying the oil agent in the oil agent application device 35, and subjected to stretching and false twisting to obtain 56 dtex, 144 filament yarns and one yarn of polyester microfiber were produced. At that time, the circumferential wind speed spot deteriorated to 11.7%. As a result, as shown in Table 1, yarn breakage occurred frequently during spinning, and the yarn-making property was poor, and the Worcester spots of the obtained ultrafine fibers were also deteriorated.
[Comparative Example 2]
Fibers equivalent to Example 6 (66 dtex, 144 filament yarns, 1 yarn) were obtained using a cross-flow type spinning cooling device. As shown in Table 1, the yarn breakage stopped several times during spinning, and the yarn-making property was poor, and the Worcester spots of the obtained fiber were poor.
[Comparative Example 3]
In the same manner as in Comparative Example 2, a fiber (84 dtex, 144 filament yarns, 1 yarn) equivalent to that in Example 5 was obtained using a cross-flow type spinning cooling device. As shown in Table 1, the Worcester spots of the obtained fibers were relatively good, but the yarn breakage stopped several times during spinning, and the yarn-making property deteriorated.

  The present invention is not limited to an annular cooling device for spinning ultrafine multifilament yarn for clothing, but also applied to an annular cooling device for spinning for industrial nylon yarn, an annular cooling device for spinning for industrial tetron yarn, etc. However, the application range is not limited to these.

It is a schematic longitudinal cross-sectional view of the cyclic | annular cooling device for spinning used for preferable embodiment of this invention. It is an AA arrow line view of FIG. It is a schematic longitudinal cross-sectional view of the cyclic | annular cooling device for spinning used for another preferable embodiment of this invention. It is a schematic longitudinal cross-sectional view of the cyclic | annular cooling device for spinning used for another preferable embodiment of this invention. It is a schematic longitudinal cross-sectional view of the cyclic | annular cooling device for spinning used for another preferable embodiment of this invention. It is a schematic longitudinal cross-sectional view of the cyclic | annular cooling device for spinning used for another preferable embodiment of this invention. It is a schematic longitudinal cross-sectional view of the cyclic | annular cooling device for spinning used for another preferable embodiment of this invention. It is a schematic longitudinal cross-sectional view of the cyclic | annular cooling device for spinning used for another preferable embodiment of this invention. It is a schematic longitudinal cross-sectional view of the cyclic | annular cooling device for spinning used for another preferable embodiment of this invention. It is a schematic longitudinal cross-sectional view of the cyclic | annular cooling device for spinning used for another preferable embodiment of this invention. It is the schematic diagram which showed the flow form of the airflow which blown off from the cyclic | annular cooling device for spinning used for preferable embodiment of this invention. It is a schematic longitudinal cross-sectional view of the conventional annular cooling device for spinning. It is a BB arrow line view of FIG. It is a schematic longitudinal cross-sectional view of the conventional annular cooling device for spinning. It is CC arrow line view of FIG. It is a schematic longitudinal cross-sectional view of the cylindrical part of the conventional annular cooling device for spinning. FIG. 10 is a development view of the cylindrical portion of FIG. 9. FIG. 10 is a development view of the cylindrical portion of FIG. 9. It is a schematic longitudinal cross-sectional view of the cylindrical part of the conventional annular cooling device for spinning. It is a schematic cross-sectional view of a conventional annular cooling device for spinning. It is a schematic longitudinal cross-sectional view of the conventional annular cooling device for spinning. It is a schematic longitudinal cross-sectional view of the melt spinning apparatus used for preferable embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Airflow supply port 2 Anti-airflow supply side 3 Cylindrical outer wall surface 4 Punching plate 5 Rectification filter 6 Stagnation point 7 Baffle plate 8 Buffer chamber 9 Cooling cylinder opening 10 Cylindrical rectification member 11 Ring-shaped rectification member 12 2nd buffer chamber 13 1st Buffer chamber 14 First buffer chamber outer wall surface 15 Second buffer chamber outer wall surface 16 Inner wall surface 17 Upper support 18 Lower support 19a 19b Packing 20 Airflow introduction pipe 21 Eccentric ring 22 Thread (multifilament yarn)
23 Spinneret 24 Spin pack 25 Spin block 26 Upper end of air flow supply port 27 Cloth (felt shape)
28 Porous cylinder 29 Nozzle hole 30 Porous cylindrical filter (filter with low filtration resistance)
31 Nonwoven fabric or paper filter with high filtration resistance 32 2nd gas chamber 33 1st gas chamber 34 Perforated plate 35 Oil agent applicator 36 37 Take-up roller 38 Winding device 39 Package 40 Effect applicator VA At the airflow supply port, wind speed Spots with reduced and uniform airflow VR Airflow that flows from the air supply port to the anti-airflow supply port along the cylindrical outer wall surface VU Airflow that flows in the upper part of the buffer chamber VS Concentric center direction perpendicular to the yarn running direction Flowing air flow VZ Yarn accompanying flow VV Updraft QTD Cooling start distance

Claims (5)

An annular cooling device for spinning, in which an airflow is blown inward from the outside of a running path of a yarn obtained by melt spinning a thermoplastic polymer to cool and solidify the airflow introduction pipe, and communicated with the airflow introduction pipe A first buffer chamber having an annular flow path disposed so as to surround the outside of the travel path of the yarn; and the travel path of the yarn located downstream of the annular flow path of the first buffer chamber. A ring-shaped rectifying member disposed so as to surround the entire downstream end of the annular flow path of the first buffer chamber, and an outer side of the yarn traveling path downstream of the ring-shaped rectifying member. An annular flow path disposed so as to surround the cross-sectional area larger than the flow path cross-sectional area in a cross section perpendicular to the traveling path of the yarn on the first buffer chamber side of the ring-shaped rectifying member. A second buffer chamber, and the yarn running inside the second buffer chamber. Spinning annular cooling apparatus characterized by having an annular rectifying filter with a flow passage for blowing the airflow is arranged to surround the outer road inwardly. 2. The annular cooling device for spinning according to claim 1, wherein a net buffer flow path length of the first buffer chamber is 3 mm or more and 80 mm or less. The annular cooling device for spinning according to claim 1 or 2, wherein dimensions of each part of the second buffer chamber satisfy the following expression.
0.09 ≦ D _2OUT ≦ 0.3 (m)
D _2INN / D _2OUT ≦ 0.95
Here, D _{2OUT represents} the outer diameter (m) of the second buffer chamber, and D _2INN represents the inner diameter (m) of the second buffer chamber. In the second buffer chamber, the second buffer chamber is disposed so as to surround the outside of the rectifying filter in each cross section perpendicular to the traveling path of the yarn in the second buffer chamber, and extends from the ring-shaped rectifying member to the rectifying filter. The annular cooling device for spinning according to any one of claims 1 to 3, further comprising a cylindrical rectifying member that rectifies all airflows. When the thermoplastic polymer is melt-spun from the spinneret and airflow is blown inward from the outside of the running path of the spun yarn to cool and solidify, the airflow introduced from the airflow introduction pipe is sent to the airflow introduction pipe. It leads to a first buffer chamber having an annular flow path arranged so as to surround the outside of the travel path of the yarn, and then is located downstream of the annular flow path of the first buffer chamber. A ring-shaped rectifying member that surrounds the outside of the yarn travel path and is disposed so as to cover the entire downstream end of the annular flow path of the first buffer chamber is allowed to pass, and thereafter, downstream of the ring-shaped rectifying member. A flow path in a cross section perpendicular to the travel path of the yarn on the first buffer chamber side of the ring-shaped rectifying member, having an annular flow path arranged so as to surround the outside of the travel path of the yarn Second buffer chamber having a cross-sectional area larger than the cross-sectional area In guidance, then melt spinning method characterized by blowing the air flow from the rectifier filter disposed annular so as to surround the outer running path of the yarn inside the second buffer chamber inwardly.

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