JP2010159514A - Apparatus for entangling yarn and method for producing polyester fiber using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus for entangling a yarn which has both high total fineness and single filament fineness like a seat belt and is woven at a high density, at a high speed of not less than 3,500 m/min, and to provide a method for producing a polyester fiber for obtaining high-quality entangled yarns. <P>SOLUTION: The yarn entanglement apparatus includes a yarn guide hole opened at both ends and extended along a yarn guide with the circumference enclosed by a wall surface, and one to four air flow nozzles that jet a high-pressure air flow and are opened at the central part position of the yarn guide hole or at a position near it. A yarn is introduced into the yarn entanglement apparatus so as to be contact-bonded, and the yarn guide hole is closed. The yarn guide hole is a tapered yarn guide hole in which both end parts have openings having larger diameters than the diameter of the yarn guide hole at the central part. The method for producing a polyester fiber includes using the entanglement apparatus. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an entanglement imparting device for injecting a fluid onto a traveling yarn to impart entanglement to multifilaments constituting the yarn, and a method for producing a polyester fiber using the same.

  When weaving a woven fabric using synthetic fibers of long fibers, in order to suppress the occurrence of fabric defects due to filament cracking during weaving, it is usually performed to entangle the raw yarn. Fabrics for industrial materials using thick yarns usually do not have a sizing process, and seat belts and sling webbings where fabric strength is particularly important are woven without twisting, so a high level of confounding quality is required. .

  However, in general, the higher the total fineness of the yarn, the more difficult it is to be entangled, and it is difficult for the thick yarn for industrial materials to be entangled. Further, since the entanglement becomes difficult to be applied as the fineness of the single yarn constituting the yarn becomes larger, the fiber for the seat belt having a large single yarn fineness is one of the most difficult to entanglement.

  On the other hand, the entanglement quality is greatly influenced by the spinning speed, and the entanglement quality is significantly deteriorated when the spinning speed is increased. Not only is the seat belt required to have high entanglement quality, but also the demand for cost reduction is very strong, so a high production capacity, that is, high-speed spinning technology is eagerly desired. Synthetic fiber production equipment and spinning technology are evolving rapidly, especially in the spinning equipment for industrial materials, and the winding speed has been increasing significantly in recent years. There is a phenomenon in which high-speed yarn production cannot be performed due to weaving restrictions.

  Conventionally, as a device for imparting entanglement to a yarn, it consists of a yarn introduction hole and a fluid injection hole that opens to the yarn introduction hole. 2. Description of the Related Art A processing device that injects air to impart confounding is used. Various fluid processing devices are designed according to the purpose, and various proposals are made such as devising the shape of the yarn introduction hole and the fluid injection angle, and providing the ejection fluid discharge hole. (For example, refer to Patent Documents 1 to 4).

  However, when these known nozzles are used to produce a fiber having a large fineness and a single yarn fineness like those for seat belts at a high speed of 3500 m / min or more, the fluff defect of the fabric increases to an unacceptable level. However, high quality fabrics cannot be obtained.

  According to the inventors' research on this cause, it has become clear that weaving defects of fibers obtained by such high-speed spinning are directly affected by some extremely large unentangled portions. It was. That is, if the distance between the entanglement points (hereinafter referred to as “non-entanglement length”) is non-uniform and the portion where the non-entanglement length is extremely large is included, more than the average number of entanglement decreases, the woven fluff The occurrence of this becomes remarkable.

  Generally, increasing the injection flow rate of compressed air used as the confounding treatment fluid decreases the unentangled length and improves the number of entangled parts.However, under such conditions, the morphological difference between the entangled part and the unentangled part increases, Single yarn breakage easily occurs. Although the statistical variation in unentangled length decreases with an increase in compressed air pressure, single yarn cracking is likely to occur and does not directly lead to the elimination of extremely long unentangled length (hereinafter referred to as `` IL missing ''). When the spinning speed is increased, simply increasing the pressure air flow rate has no effect on the reduction of fuzz defects.

  From this point of view, as the fiber for the seat belt, the distribution of the non-entangled length is sharper than the number of the entangled number, the IL missing is small, and there is a certain degree of entanglement between the single yarns even in the non-entangled part. It is important to have a confounding form.

  However, the conventionally known entanglement processing technique is suitable for seat belt fibers because the number of entanglement is extremely reduced or the single yarn cracking of the unentangled part is increased if an attempt is made to reduce the variation of the unentangled length. The confounding process cannot be performed with high efficiency.

JP 55-67030 A JP 58-65029 A JP-A-63-152435 JP 2001-303380 A

  The present invention has been made in view of the above-described problems of the prior art, and entanglement treatment is performed at a high speed of 3500 m / min or higher for fibers woven at a high density, both of a total fineness and a single yarn fineness as in a seat belt. It is an object of the present invention to provide an apparatus for producing polyester fiber and a method for producing polyester fiber for obtaining a good quality entangled yarn.

  As a result of intensive studies by the present inventors in order to achieve the above-mentioned problems, it was found that fibers suitable for high-density weaving can be obtained even with high-speed processing by the following entanglement processing apparatus, and the present invention has been achieved. .

  Here, as the present invention according to claim 1 for solving the above-mentioned problem, “the yarn guide hole extending along the yarn guide having both ends opened and surrounded by the wall surface; A yarn having a structure in which one to four air flow injection holes are opened at a central position of the yarn introduction hole or in the vicinity thereof, and the yarn is introduced into the entanglement processing apparatus and then crimped to close the yarn introduction hole. There is provided an entanglement processing device, wherein both ends of the yarn introduction hole are tapered yarn introduction holes having openings larger than the diameter of the central yarn introduction hole. The

  At this time, as in the present invention according to claim 2, the ratio (D1 / D2) of the hole diameter (D1) of the both ends opening of the yarn introduction hole and the hole diameter (D2) of the center portion of the yarn introduction hole is 1 4 to 1.8, the entanglement processing device according to claim 1, and, as in the present invention according to claim 3, “at both ends of the yarn introduction hole, with respect to the yarn introduction hole total length L. The entanglement processing apparatus according to claim 1 or 2, which has a linear hole shape whose diameter does not substantially change in a range of 0 to 0.2 L. Further, as in the present invention according to claim 4, it is preferable that the “entanglement processing apparatus according to claim 1, wherein the number of the airflow injection holes is two”.

  As in the present invention according to claim 5 as a fiber manufacturing method using the above-mentioned apparatus, “the high-pressure air flow to be introduced into the entanglement processing apparatus is compressed air, and the pressure is 0.6 to 1.0 MPa, the entanglement processing apparatus. The manufacturing method of the polyester fiber in any one of Claims 1-4 whose tension | tensile_strength of the thread | yarn which passes is 0.15-0.22g / dtex, and the speed of thread | yarn passing is 3500-6000m / min. Is provided.

  At this time, as in the present invention according to claim 6, “the total fineness of the polyester fiber is 560 to 2200 dtex, the single yarn fineness is 8 to 15 dtex, and the tensile strength is 7.0 cN / dtex or more. It is preferable that the “method for producing polyester fiber”.

  As described above, by using the entanglement processing apparatus of the present invention, even if the entanglement process is performed at a high speed of 3500 m / min or more, the distribution of the unentangled length is sharp and the IL has an extremely long unentangled length. A fiber to which continuous entanglement is imparted with little missing and a small difference in form between the unentangled portion and the entangled portion can be obtained. When a seat belt is woven using such fibers, a seat belt webbing with less generation of woven fluff and excellent quality can be obtained.

It is sectional drawing along the running direction of the yarn which shows one Example of the confounding provision apparatus of this invention.

Hereinafter, embodiments of the present invention will be described in detail.
FIG. 1 is a cross-sectional view along the running direction of a yarn showing an example of the entanglement imparting device of the present invention. Regarding the reference numerals shown in the figure, 1 is an entanglement processing device body, 2 is a yarn introduction hole, and 3 Indicates gas injection holes, respectively. In FIG. 1, the fracture surface indicates a surface cut in a state including the center line of the yarn introduction hole 2 and the center line of the gas injection hole 3 formed in the central portion of the confounding apparatus 1. . Hereinafter, the “entanglement imparting device” is simply referred to as “nozzle”.

  The nozzle body 1 employs a half structure in which the nozzle body 1 is divided into two at the center of the yarn introduction hole 2 in order to introduce the yarn into the yarn introduction hole 2. Therefore, when the halved portion is opened and the yarn is introduced into the yarn introduction hole 2 and the yarn hooking is finished, the halved yarn introduction holes 2 are immediately brought into close contact with each other and the half portion is closed. Except for the circular opening, the side wall in the yarn guide hole 2 is crafted so that the slit-like opening for introducing the yarn is completely closed and surrounded by the hole wall.

  In this way, even when the flow rate of high-pressure compressed air (also simply referred to as “pressure air” in the present invention) is increased, the slit-shaped yarn introduction opening provided on the side wall of the yarn guide hole 2 is provided. As a result, there is no flow of airflow in a specific direction, and the fluid becomes a complete turbulent flow in the yarn introduction hole 2 so that the filament can be effectively opened. Furthermore, it is possible to suppress the occurrence of single yarn breakage and fluff due to the filament entering the half slit.

  On the other hand, a slit for introducing the yarn into the yarn introduction hole 2 is formed without adopting the half structure, and the slit is opened even after the yarn is introduced into the yarn introduction hole 2. When a nozzle having a structure left as it is is used, many problems as described below arise. That is, entanglement processing like a fiber for a seat belt is difficult because high-pressure air leaks from the opened slit portion. In addition, an edge portion is formed in the portion where the slit opens to the yarn guide hole 2, and the running yarn is caught or scratched on the edge portion to generate fluff (filament breakage), resulting in high fluff quality. However, a fiber with satisfactory performance cannot be obtained.

  As a result of detailed observation of the filament opening state in the yarn introduction hole portion by a high-speed camera, the present inventors have found that a conventional nozzle having a linear yarn introduction hole has a filament above the yarn introduction hole. It was found out that the opening of the fibers disappeared periodically, and that IL loss occurred at that moment. As a result, by making both ends of the yarn introduction hole 2 into a tapered shape, the opening of the filament becomes large immediately before the yarn enters the nozzle, and the opening can be stably maintained. They discovered that they can form confounding.

  Therefore, the greatest feature of the entanglement imparting device (nozzle) according to the present invention is that the end portions of the yarn introduction hole 2 are each formed with a taper that widens toward the inlet opening and the outlet opening of the yarn. At this time, as the shape of the taper, the ratio of the hole diameter at the opening at both ends of the yarn introduction hole 2 to the center hole diameter is 1.3 to 1.8, more preferably 1.5 to 1.6. It is necessary to. In addition, the length of each portion whose diameter is expanded in a tapered shape toward both end openings is preferably 1 / 6L to 1 / 3L, where L is the total length of the yarn introduction hole 2.

  This is because when the taper ratio is less than 1.3, it is not preferable because a sufficient opening stabilization effect cannot be obtained, and conversely, when the taper ratio exceeds 1.8, the taper ratio is ejected from the yarn introduction hole 2. This is because the flow of compressed air becomes extremely unstable, and uniform opening is hindered.

  However, even a conventionally known nozzle has been proposed in which both end openings have thread guide holes wider than the center. For example, Japanese Patent Laid-Open No. 2000-73243 discloses an entanglement processing apparatus having a tapered thread guide hole. However, this is for the purpose of preventing fretting for suppressing fuzz, and is not a textile entanglement nozzle for industrial materials as in the present invention, but a textile POY nozzle with a small total fineness.

  Therefore, compared with the nozzle of the present invention using high pressure air pressure of 0.7 MPa or more, the confounding process is performed at a pressure as low as about 0.3 MPa, and the taper ratio is larger than that of the nozzle of the present invention. It is completely different from the function and effect. In the present invention, more effective entanglement processing can be performed by using high-pressure compressed air of 0.7 MPa or more. However, in consideration of cost loss due to waste of compressed air, compressed air exceeding 1.0 MPa is used. The profit is not so great.

  By the way, when the yarn introduction hole 2 has a tapered shape, there is a characteristic that the direction of the airflow discharged from the yarn introduction hole 2 tends to become unstable. This is caused by a slight difference in taper angle at both ends of the yarn guide hole 2 due to dimensional variation when processing the nozzle, and this destabilization phenomenon occurs particularly when high pressure air pressure of 0.7 MPa or more is used. Becomes prominent. For this reason, when a plurality of nozzles are manufactured, if the manufacturing dimensions vary, some of the nozzles cannot obtain a stable airflow.

  On the other hand, by providing a linear portion where the diameter of the yarn guide hole 2 does not change within a range of 0.2 L at the maximum with respect to the total length L of the nozzle at the both ends of the tapered portion of the thread, Stability can be significantly improved. Even with a nozzle having such a structure, the effect of stabilizing the opening is equivalent to that of the apparatus having the thread guide hole 2 having only a tapered portion without a linear portion at both ends, and conversely, the reproducibility of nozzle production is obtained. It is preferable because it is easy.

  When the total length L of the nozzle is 20 to 50 mm, more preferably 35 to 45 mm, the number of entanglements applied to the filament is maximized, and the variation of the unentangled length is also minimized. The cross-sectional shape of the yarn introduction hole 2 may be various, such as a circle, a rectangle, and a triangle, but is preferably an oval, and more preferably the ratio of the minor axis to the major axis is 0.6 to 0.9, more preferably 0.7 to 0.8. At this time, the thread guide hole diameter referred to in the present invention, that is, the values of D1 and D2 are represented by the value of the major diameter.

  As described above, regarding the tapered portion of the thread guide hole 2 having an oval shape, it is necessary to gradually increase the hole area while maintaining the oval shape of the central portion as it is. Further, since the edge part of the end opening of the yarn introduction hole 2 causes fluffing due to abrasion with the yarn, in order to prevent this, it is not possible to apply a rounding process with a radius of curvature of about 1 mm to the edge part. no problem.

  In the present invention, preferably 1 to 4 gas injection holes 3 are provided. This is because, according to the experiments by the present inventors, the effect is obtained even if the number of the gas injection holes 3 is one, but the case where the number of the gas injection holes 3 is two is most stably entangled. It can be imparted and is effective in providing uniform entanglement, which is preferable. However, when the number of the gas injection holes 3 is 5 or more, a large difference is not recognized in the confounding imparting effect, and the cost of drilling the gas injection holes 3 increases, which is not preferable from this aspect. In addition, it is preferable that the position where the gas injection hole 3 opens to the yarn introduction hole is a central portion position of the yarn introduction hole 2 or a position in the vicinity thereof as illustrated in FIG.

  The nozzle described in detail above is preferably installed in the process after the fiber has been drawn. Specifically, after the final drawing is completed, it may be processed in a relaxation heat treatment process, or may be processed in an intermediate process between a cooling roller and a winder for cooling the heat-treated yarn.

  In this case, the yarn tension in the entanglement treatment step needs to be in the range of 0.15 to 0.22 g / dtex, more preferably 0.18 to 0.20 g / dtex. This is because when the yarn tension is 0.15 g / dtex or less, the yarn is easily wound around the drawing roll disposed immediately before the nozzle, and stable yarn cannot be produced. This is because a tension exceeding dtex is not preferable because the filament is not sufficiently opened in the nozzle and the number of entanglements is significantly reduced.

  In general, in the drawing process of high strength fibers such as seat belt fibers, the yarn tension in the relaxation thermal travel process reaches 0.4 to 1.5 g / dtex. Therefore, in such a drawing process of high-strength fibers, it is not possible to ensure an appropriate yarn tension by applying an entanglement treatment under a high yarn tension. For this reason, it is preferable to install the nozzle in an intermediate process between the cooling roller and the winding device that can ensure proper yarn tension.

  The nozzle of the present invention exhibits an excellent effect even in low-speed spinning with a processing speed of 3500 m / min or less, but exhibits its true value particularly in high-speed processing of a maximum of 6000 m / min class. In addition, as a fiber which can be suitably produced with the nozzle of the present invention, 90% or more is a polyester composed of ethylene terephthalate units, the total fineness is 560 to 2200 dtex, more preferably 1100 to 1670 dtex, and the single yarn fineness is 8 to 15 dtex. The fiber for seat belts has a tensile strength of 7.0 cN / dtex or more, more preferably 7.8 cN / dtex or more.

Hereinafter, the present invention will be described more specifically with reference to examples. In addition, each physical property value in an Example was based on the following measuring method.
<Number of confounding>
Using an Itemat-type interlace measuring device manufactured by Enka Technika, the multifilament yarn wound up by entanglement after drawing was measured under the conditions of measuring speed: 100 m / min, sample length: 30 m, stretch: 0.3% The number of entanglements per meter was calculated from the average value of the entanglement length.
<Non-entanglement length variation>
Similarly to the measurement of the number of entanglements, the standard deviation of the unentangled length measured using the Itemat interlace measuring device manufactured by Enka Technika under the conditions of measurement speed: 100 m / min, sample length: 30 m, stretch: 0.3% The variation.
<IL missing>
Similar to the number of entanglement and non-entangled length variation, using an Itemat type interlace measuring instrument manufactured by Enka Technika, measurement speed: 100 m / min, sample length: 100 m, stretch: 0.3% Those having a length of 20 cm or more were judged as “IL missing”, and the number of IL missing existing in the measurement length of 100 m was counted.
<Weaving workability>
400 wound packages of 10 kg wound entangled yarn were prepared, and in accordance with a conventional method, a non-twisted 50 mm wide needle loom was woven at a speed of 1300 rpm to produce an automobile seat belt, followed by dyeing. . The dyed belt is inspected using a surface fluff detection device, and “○” indicates that the number of fluff defects detected in the belt of 200 m is 0 to 2, and “△” indicates 2 to 5 defects. More than 5 items were represented by “x”.

[Examples 1-2, Comparative Examples 1-3]
Polyethylene terephthalate chips whose intrinsic viscosity has been increased to 1.00 by solid-phase polymerization are melted at a melting temperature of 310 ° C. using an extruder, and melted from a spinneret having 96 holes and 0.6 mm hole diameter. The discharged yarn was cooled and solidified by blowing cold air of 25 ° C. over the discharged yarn. The obtained undrawn yarn is provided with 0.5% by weight of a spinning oil agent, continuously supplied to the drawing process without being wound once, and after two-stage drawing at a total draw ratio of 4.8 times, a set at 230 ° C. Heat set with a roller.

The heat-set stretched yarn was passed through a nozzle shown in Table 1 arranged between the final draw roll and the winder and entangled to wind up at a speed of 5000 m / min. At this time, compressed air was supplied to the yarn introduction hole from two air flow injection holes (hole diameter: 2.9 mm) opened at the center of the yarn introduction hole, and the pressure of the compressed air was set to 0.7 MPa. At that time, the speed of the final roll was adjusted so that the winding tension of the multifilament yarn immediately after passing through the nozzle was 200 g. The fineness of the obtained yarn was 1100 dtex, and the strength was 7.9 cN / dtex.
Table 1 shows the results of evaluating the entanglement quality and weaving processability of the entangled multifilament yarns for Examples 1-2 and Comparative Examples 1-3 described above.

1: Entangling device body (nozzle body)
2: Yarn guide hole 3: Fluid injection hole

Claims (6)

  A yarn guide hole that is open at both ends and extends along the yarn guide surrounded by a wall surface, and one to four air currents that inject a high-pressure air stream and open at a central position of the yarn guide hole or in the vicinity thereof A yarn entanglement processing device having a structure having injection holes and having a structure in which the yarn introduction hole is introduced into the entanglement processing device and then crimped to close the yarn introduction hole. An entanglement processing apparatus, which is a tapered thread guide hole having an opening larger than the diameter of the hole.   The ratio (D1 / D2) of the hole diameter (D1) of the both ends opening of the said yarn introduction hole and the hole diameter (D2) of the center part of the said yarn introduction hole is 1.4-1.8. Confounding processing device.   The entanglement process according to claim 1 or 2, wherein at both ends of the yarn introduction hole, the yarn introduction hole has a linear hole shape whose diameter does not substantially change in a range of 0 to 0.2 L with respect to the entire length L of the yarn introduction hole. apparatus.   The entanglement processing apparatus according to any one of claims 1 to 3, wherein the number of the air flow injection holes is two.   The high-pressure air flow introduced into the entanglement processing device is compressed air, the pressure is 0.6 to 1.0 MPa, the tension of the yarn passing through the entanglement processing device is 0.15 to 0.22 g / dtex, and the yarn The method for producing a polyester fiber according to any one of claims 1 to 4, wherein the strip passage speed is 3500 to 6000 m / min.   The method for producing a polyester fiber according to claim 5, wherein the total fineness of the polyester fiber is 560 to 2200 dtex, the single yarn fineness is 8 to 15 dtex, and the tensile strength is 7.0 cN / dtex or more.

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