JP2007077547A - Method for producing super fine polyamide multifilament and apparatus for melt-spinning polyamide multifilament yarn - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing a super fine polyamide multifilament, by which the super fine polyamide multifilament having a good dyeing quality can be produced in good productivity under excellent fiber-producing operability, and to provide an apparatus therefor. <P>SOLUTION: This method for producing a polyamide multifilament yarn having a single filament fineness of ≤0.8 dtex and comprising ≥50 filaments is characterized by melt-extruding a polyamide from a spinneret in which extrusion holes are circumferentially arranged, blowing a cooling gas on the spun filaments from the whole circumferential directions from a cylindrical cooling device disposed to surround the filaments to cool the filaments, oiling the filaments, further interlacing the filaments, and then winding up the filaments on a take-up device through at least a pair of goddet rollers at a large winding rate of 3,500 to 5,000 m/min. And the apparatus for melt-spinning the polyamide multifilament yarn. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method and an apparatus for producing an ultrafine polyamide multifilament having a dyeing quality of a single yarn fineness of 0.8 dtex or less and 50 filaments or more with high productivity under excellent yarn-manufacturability. .

  Polyamide fiber, which is one of the synthetic fibers, has excellent characteristics such as high strength, abrasion resistance, softness, and clearness of dyeing. Therefore, legwear such as pantyhose and tights, innerwear such as lingerie and foundation. It has been used favorably for apparel applications such as clothing, sportswear and casual wear.

  In recent years, the tendency to demand a further soft feeling has increased, and the conventional filament having a single yarn fineness of 1 dtex or more cannot be expected to have a soft feeling.

  As a method of obtaining a filament with a fine single yarn fineness, in addition to a method of direct spinning, two or more kinds of polymers are compound-spun into a so-called sea-island type by compound spinning, and divided in a high-order processing process, or a specific polymer is A method of producing by elution is known. However, in the composite spinning method, there are difficulties in spinning and poor productivity due to melting two or more types of polymers, and furthermore, the equipment is required to be very expensive, and it is divided in a high-order processing step. There is a disadvantage that the number of processing steps such as elution is increased, and the cost is much disadvantageous compared to the direct spinning method.

  On the other hand, in the direct spinning method, it is possible to improve the soft feeling by reducing the single yarn fineness. However, in the direct spinning method, when the single yarn fineness is made thin while maintaining the yarn fineness as it is, the number of filaments discharged from the spinneret becomes very large, and cooling air is blown out from one direction conventionally used. In this type of cooling device, the difference in distance from the cooling air outlet to each filament is large, and it has been difficult to perform sufficient uniform cooling. As a result, due to the difference due to the cooling history, a problem was caused in terms of quality such as yarn breakage and dyeing spots due to fiber structure differences.

  As a means for solving such a problem, a method of using a cooling device that blows cold air from the periphery of the spinning device, that is, a so-called improved annular chimney, for the purpose of uniform cooling of the yarn (see, for example, Patent Document 1) However, this circular chimney blows cold air from the surroundings to the yarn, so the cooling air collides with the center and creates turbulence, resulting in intense yarn swinging and several filaments A phenomenon of fusing was sometimes observed. In addition, in order to prevent fusion, the blowing amount of cooling air must be made as small as possible, and the spinning speed needs to be remarkably reduced accordingly. It was.

  Even if the filament is not fused, the cooling air generates turbulent flow in the yarn. There is a problem in that oily spots occur due to the occurrence of a portion where oil is supplied and a portion where oil is not supplied. Usually, the oil agent is applied to the yarn as a water-containing oil agent in the form of an emulsion with water. However, since the polyamide fiber changes in the crystallization state in the subsequent drawing process due to moisture, this oil agent is used as much as possible. It is known that it is necessary to uniformly apply to the yarn, and if it is not uniformly applied, dyeing spots are generated in the dyeing process.

Incidentally, a polyester fiber melt spinning method (for example, see Patent Document 2) is known, in which a split yarn is fed at a high speed of 5000 m / min or more and then combined, but according to a follow-up test by the present inventors. Even if a water-containing oil agent is applied to the yarn in order to apply this method to a polyamide multifilament and obtain an oil content of 0.4 to 1.2% by weight which is generally applied, the moisture content is not sufficient. The occurrence of spots was found to be unavoidable.
JP 59-163410 A Japanese Patent Laid-Open No. 07-243129

  The present invention has been achieved as a result of examining the solution of the problems in the above-described prior art as an object.

  Accordingly, an object of the present invention is to provide a method and an apparatus for producing an ultrafine polyamide multifilament having a single yarn fineness with a good dyeing quality of 0.8 dtex or less and 50 filaments or more with high productivity under excellent yarn-manufacturability. Is to provide.

  In order to achieve the above object, according to the present invention, in a method for producing a polyamide multifilament yarn having a single yarn fineness of 0.8 dtex or less and 50 filaments or more, the discharge holes of polyamide are arranged circumferentially. It is melted and discharged from one spinneret, and cooled by blowing cooling air from the entire circumference to the yarn by a cylindrical cooling device installed so as to surround the spun yarn, and then refueling, Furthermore, a method for producing an ultrafine polyamide multifilament yarn is provided, which is entangled and wound around a winding device at a high speed of 3500 to 5000 m / min via at least one pair of godet rollers.

In the method for producing the ultrafine polyamide multifilament yarn of the present invention,
The refueling method is to perform the first stage of refueling, and after further confounding, to perform the second stage of refueling,
As a water-containing oil agent, the oil supply amount of 25% by weight or more is supplied with respect to the polymer discharge amount, and then the first-stage oil supply is performed. The second level of refueling,
Dividing the spun yarn into two or more and performing the first stage of refueling, then combining and confounding as a single thread, and then performing the second stage of refueling;
The first stage of lubrication is performed at a position 400 to 1800 mm from the spinneret, and the first stage of lubrication is applied by the lubrication guide, and the diameter of the circle drawn by the discharge holes arranged on the circumference is a. (Mm), where the distance between the oil supply guides is b (mm), and the number of divided yarns is n, a, b, and n have the relationship 1 / (n + 1) ≦ b / a ≦ 1 / n Any of these may be mentioned as preferable conditions.

  The apparatus of the present invention includes a spinneret in which discharge holes are arranged circumferentially, a cylindrical cooling device installed so as to surround the spun yarn, a first-stage oil supply device, an entanglement This is a polyamide multifilament yarn melt spinning device in which an applying device, a second-stage oiling device, at least one pair of godet rollers and a winding device are arranged in order from the upstream side of spinning.

  According to the present invention, as will be described below, an ultrafine polyamide multifilament having a single yarn fineness with good dyeing quality of 0.8 dtex or less and 50 filaments or more is manufactured with high productivity under excellent yarn-manufacturability. can do.

  Hereinafter, the present invention will be described in detail.

  The polyamide used in the present invention is a high molecular weight product in which a so-called hydrocarbon group is connected to the main chain via an amide bond, and the kind thereof is not particularly limited. Examples thereof include polycapramide, polyhexamethylene adipamide, polydodecanoamide, polymetaxylylene adipamide and the like. Preferable are polycapramide and polyhexamethylene adipamide widely used for clothing applications. Further, in the polyamide in the present invention, various copolymerization components and additives such as a matting agent, a flame retardant, an antioxidant, an ultraviolet absorber, an infrared absorber, an antistatic agent, and the like are copolymerized as necessary. Or you may mix.

  In the method for producing an ultrafine polyamide multifilament of the present invention, the polyamide is melted and discharged from a single spinneret in which discharge holes are arranged circumferentially, and a cylindrical shape installed so as to surround the spun yarn. After cooling so as to blow cooling air from the entire circumferential direction to the yarn by the cooling device, refueling, further confounding, stretching through at least one pair of godet rollers, to the winding device It is necessary to wind up at a high speed of 3500 to 5000 m / min.

  FIG. 1 is an explanatory view showing an example of an apparatus for carrying out the present invention. In FIG. 1, reference numeral 1 denotes a spin block in a melt spinning machine, which is heated by a heating means (not shown). A spinneret 2 is attached to the spin block 1, a polymer is extruded to form a thread, and after passing through an annular chimney 3 provided on the downstream side of the base 2, it is divided into two parts by first oiling guides 4, 5. After the oil agent is applied, the yarns are combined and further interlaced by the entanglement nozzle 6. Then, the oil agent is applied by the second oil supply guide 7 and taken up by the first goded roller 8. And then traversed by a traverse 10 and taken up by a roller bale 11 and a spindle 12.

  In order to achieve uniform cooling to each filament, the spinneret 2 used in the present invention needs to have a constant distance to the cooling air, and each discharge hole 2a has a circular shape as shown in FIG. It must be a circumferential array. An arrangement of up to a three-row circumferential arrangement is preferred.

  The cooling device used in the present invention uses a cylindrical cooling device made to surround the base in order to make the distance to the cooling air constant.

  As shown in FIG. 3, the cooling method in the production of the ultrafine polyamide multifilament according to the present invention is carried out by the cylindrical cooling device 3 installed so as to surround the spun yarn. It is necessary that the cooling air 13 is blown out slightly in the direction of the yarn running as indicated by the arrow from the direction and cooled. By blowing cooling air from the entire circumference to the yarn so as to surround the yarn, the distance from the cooling device to each filament becomes uniform, and each filament is uniformly cooled. In the cooling by cooling air from one direction that has been often used in the past, the distance from the cooling device to each filament differs depending on whether it is near or far from the cooling device. The filaments of this product will be slowly cooled and solidified, resulting in differences in the cooling history between the filaments, easily resulting in fiber structure differences, etc. In this case, the fluff and thread breakage are likely to occur and the productivity is inferior. However, in the present invention, as described above, by blowing cooling air in a direction substantially perpendicular to the running yarn from the outside toward the inside (a little running direction of the yarn) so as to surround the yarn, The conventional problem is solved efficiently. The cooling air is preferably 20 ° C. or less, more preferably 18 ° C. or less, in order to sufficiently cool and solidify and uniformly cool the yarn.

  In the method for producing the ultrafine polyamide multifilament of the present invention, it is preferable that the first-stage oil supply is performed, and the second-stage oil supply is performed after confounding.

  Unlike polyester, polyamide is a polymer that is easily crystallized by water. Therefore, the fiber structure (orientation crystallization) differs in each filament depending on the amount of water during refueling. This difference in the fiber structure becomes a dyeing difference in the dyeing process and generates dyeing spots. Therefore, it is important to give sufficient moisture to each filament. However, in the case of water replenishment at the first stage only, if a sufficient amount of moisture is applied, the amount of oil attached becomes excessive or insufficient, making it difficult to control the oil content and increasing thread breakage. Or fluffing occurs, and productivity decreases. In order to attach an appropriate amount of oil and moisture, it is necessary to supply a large amount of an oil agent having an oil agent concentration of 5 to 15% by weight, and the oil agent is often wasted. Therefore, by providing a sufficient amount of moisture to the polyamide multifilament with the first stage of oil supply, and adding oil with the second stage of oil supply, the fiber structure of each filament can be made uniform, and Appropriate amount of oil can be deposited. In the case of non-hydrous oiling, there is no problem with the dyeing property even with only the first-stage oiling, but uniform application is difficult and the yarn-making property is inferior.

  In the first-stage oil supply in the present invention, a water-containing oil agent having a concentration higher than that of the first-stage oil supply is obtained by supplying an oil amount of 25% by weight or more with respect to the polymer discharge amount as a water-containing oil agent. It is preferable that second-stage refueling is performed.

  The oil agent used for the first-stage oil supply in the present invention is preferably a hydrous oil agent mainly for the purpose of imparting moisture. The oil agent concentration (surfactant concentration) of the hydrated oil agent is preferably 1.5% by weight or less, and more preferably 0.4 to 1.2% by weight. When the oil agent concentration is less than 0.4% by weight, the water permeability to each filament is deteriorated. If it exceeds 1.5% by weight, it becomes difficult to get moisture, and the oil supply / discharge amount has to be increased. As a result, a large amount of oil is required, and not only the waste of the oil increases, but also due to scattering of the oil. Product defects due to deterioration of the working environment and product contamination increase, resulting in reduced production efficiency.

  In particular, in the case of multifilaments of 50 filaments or more, a sufficient amount of water cannot be supplied to each filament if the amount of oil supply is small, so an oil supply amount of 25% by weight or more with respect to the polymer discharge amount is preferable, and more preferably 28 to 35% by weight.

  In addition, by entangling before the second stage of refueling, the oil agent excessively applied by the first stage of refueling is blown away, and the uniform imparting property of the oil agent to each filament increases due to the migration effect. The second-stage refueling can also improve the uniform imparting property.

  The oil agent used for the second stage oil supply in the present invention is mainly intended to impart the original active ingredient of the oil agent, and therefore a hydrous oil agent having a higher concentration than the oil agent used for the first stage oil supply should be used. Is preferred. The oil concentration of the hydrous oil is more preferably 8 to 16% by weight. By setting it as this range, it can be set as an appropriate oil supply amount and can improve the uniform adhesion of oil.

  As an oil supply method in the present invention, for example, as shown in FIG. 1, the yarn is divided into two or more, and the first-stage oil supply (4, 5) is performed, and the yarns are combined and entangled as one yarn ( After applying 6), it is preferable to perform second-stage refueling (7).

  In particular, a multifilament having 50 filaments or more is preferably divided into two or more. As the number of divisions per yarn, it can be divided into 2 for 50 to 100 filaments, 3 for 100 to 150 filaments, and further for 150 or more filaments depending on the situation. By setting it as such a range, a water | moisture content can adhere uniformly to each filament, and the polyamide multifilament with the favorable dyeing quality without a dyeing spot can be obtained.

  Moreover, it is preferable that the first-stage oil supply method supplies oil at a position 400 to 1800 mm from the spinneret 2. If the length is shorter than 400 mm, the accompanying airflow brought in by the yarn is small, so that the oil agent is less scattered at the time of refueling. However, since each filament converges in a state where it is not sufficiently cooled, fusion of adjacent filaments occurs. Or the occurrence of fluff increases and the productivity tends to decrease. In addition, when the distance is 1800 mm or more, the accompanying airflow that the yarn brings increases, the scattering of the oil agent at the time of refueling is not only difficult, it is difficult to uniformly apply the oil agent, and cooling air is emitted from the outside to the inside, The cooling air becomes a swirling flow inside the yarn, and the yarn sway increases, resulting in yarn breakage and fusion of adjacent filaments, and the production tends to decrease. More preferably, the position is 600 to 1600 mm from the spinneret 2.

  Furthermore, in the first-stage oil supply method, an oil agent is applied by an oil supply guide, the diameter of a circle drawn by a cap hole arranged on the circumference is a (mm), the interval of the oil supply guide is b (mm), and divided. When the number is n, it is preferable that a, b, and n have a relationship of the formula 1 / (n + 1) ≦ b / a ≦ 1 / n.

  The position of the divided oil supply guide is preferably the center position of the cap hole of the filament group that uses the guide. When the interval b (mm) between the oil supply guides is reduced, uniform oil supply becomes difficult because of the influence of the accompanying airflow.

In the method for producing an ultrafine polyamide multifilament according to the present invention, after the oil agent is applied, at least a pair of goded rollers (8, 9) is used, but whether or not a heated roller is used is optional. is there. Moreover, you may extend | stretch 1.0-3.0 times between rollers.
The winding speed in the method for producing the ultrafine polyamide multifilament of the present invention needs to be 3500 to 5000 m / min. When the speed is less than 3500 m / min, the take-up speed (speed of the roller 8) is slow. In particular, for example, when drawing at a draw ratio of 1.8 times, the take-up speed is as low as 2000 m / min, and the polyamide fiber structure is This will give moisture as a plasticizer to low-orientation, low-crystallinity undrawn yarn, and a little non-uniformity will give a difference in the fiber structure (orientation crystallization) in the subsequent drawing process. Causes spots. On the other hand, when the winding speed is increased, the productivity is improved. However, when the winding speed exceeds 5000 m / min, the yarn swaying is caused by the increase in the associated airflow particularly in a filament having a fine single yarn fineness of 0.8 dtex or less. Increases, resulting in an increase in yarn breakage and an increase in fluff, resulting in a decrease in productivity.

  The method for producing ultrafine polyamide multifilaments referred to in the present invention works effectively in such a range of 0.8 dtex or less and 50 filaments or more.

  As described above, according to the present invention, an ultrafine polyamide multifilament having a single yarn fineness with good dyeing quality of 0.8 dtex or less and 50 filaments or more is manufactured with high productivity under excellent yarn-manufacturability. can do.

  Hereinafter, the present invention will be described more specifically with reference to examples. In addition, each measured value and evaluation method in an Example and a comparative example were obtained with the following method.

[Worcester spots (U%)]
The variation in thickness in the longitudinal direction of the fiber measured with USTER TESTER III manufactured by Keisoki was measured and evaluated by the obtained U% (HI). The measurement conditions were a yarn speed of 100 m / min and 5 minutes.

[Dyeing quality]
The fiber was subjected to tube knitting (cylinder knitting length 15 cm) and dyed (metal-containing dye Palatine Fast Black WAN, 0.5% by weight), and then visually determined. The evaluation is made in 5 stages, and the evaluation criteria are as follows.
○: No staining spots are seen, pass,
○ to △: If you look closely, you can see stained spots, but pass,
Δ: Some stained spots are visible, but in practical use, it is within the scope of the problem.
Δ to ×: stained spots are visible, fail,
X: Dyeing spots are conspicuous and fail.

[Spinning property]
1 t of yarn was made, and the yarn forming property was evaluated by the number of yarn breaks during that time.

[98% sulfuric acid viscosity]
The chip was dissolved in 98% sulfuric acid, measured with an Ostwald viscometer at a constant temperature of 25 ° C., and the viscosity ratio of 98% sulfuric acid was shown.

[Examples 1, 2, 4 to 6]
A polyhexamethylene adipamide chip with 98% sulfuric acid relative viscosity of 2.60 was melted at 290 ° C., and the discharge holes shown in FIG. 2 were circumferentially arranged in a row (hole diameter 0.15 mm, a = 80 mm) 1 and was manufactured by the process shown in FIG. That is, the spun yarn was cooled by a circular chimney (1) so that cooling air of 16 ° C. was blown from the entire circumferential direction to the yarn, and the first stage oil supply (4, 5) and after confounding, the second-stage oil supply (7) is performed under the conditions shown in Table 1, and the first goded roller (8) and the second goded roller (9) (magnification 1.04) ) To a winding device (10) at 4200 m / min to obtain a polyhexamethylene adipamide multifilament with 56 dtex 98 filaments.

  The obtained polyhexamethylene adipamide filament was evaluated for Wooster spots, dyeing quality, and yarn-making property as shown in Table 1.

[Example 3, Comparative Examples 1 and 2]
Spinning was carried out in the same manner as in Example 1 except that the winding speed was 4800, 3000, and 5500 m / min, to obtain polyhexamethylene adipamide multifilaments of 56 dtex 98 filaments.

  The obtained polyhexamethylene adipamide filament was evaluated for Wooster spots, dyeing quality, and yarn-making property as shown in Table 1.

[Comparative Example 3]
Spinning was performed in the same manner as in Example 1 except that the spun yarn was cooled by cooling air from one direction to obtain a polyhexamethylene adipamide multifilament of 56 dtex 98 filament. The hexamethylene adipamide filaments were evaluated for Wooster spots, dyeing quality, and yarn-making property as shown in Table 1.

[Comparative Example 4]
Spinning was carried out in the same manner as in Example 1 except that the oil agent concentration at the first stage was 6% by weight and the oil supply at the second stage was not performed, to obtain polyhexamethylene adipamide multifilaments of 56 dtex 98 filaments.

  The obtained polyhexamethylene adipamide filament was evaluated for Wooster spots, dyeing quality, and yarn-making property as shown in Table 1.

  As a result of the above Examples 1 to 6, the yarn-making property was at a level that can be endured as production (thread breakage: 1 to 6 times / t), and good results were obtained with respect to the dyeing quality and Wooster spots.

  On the other hand, Comparative Examples 1, 3, and 4 have a lower winding speed than Examples 1 to 6, a cooling device using cooling air from one direction, and the second stage without oil supply have poor dyeing quality. It turns out that it passes. Moreover, it turns out that the comparative example 2 has high thread breakage | shortage compared with Examples 1-6, and is inferior to productivity.

  According to the present invention, since the single yarn fineness with good dyeing quality is 0.8 dtex or less and 50 filaments or more, an ultrafine polyamide multifilament can be produced with good productivity under excellent yarn production operability. It can be said that the contribution to the synthetic fiber industry is high.

Explanatory drawing which shows an example of the apparatus for implementing this invention Plan view showing an example of a spinneret used in the present invention Explanatory drawing which shows an example of the cooling device used by this invention

Explanation of symbols

1: Spin block 2: Spinneret 2a: Discharge hole 3: Cylindrical cooling device (annular chimney)
4: First-stage lubrication device 5: First-stage lubrication device 6: Entangling nozzle 7: Second-stage lubrication device 8: First goded roller 9: Second goded roller 10: Traverse 11: Roller bale 12: Spindle 13 : Cooling air a: Diameter of a circle drawn by the discharge hole of the base b: Distance between two cooling devices

Claims (9)

In a method for producing a polyamide multifilament yarn having a single yarn fineness of 0.8 dtex or less and 50 filaments or more, the polyamide is melted and discharged from one spinneret in which discharge holes are arranged circumferentially, and the spun yarn At least one pair of godet rollers is supplied with oil after being cooled by blowing a cooling air from the entire circumference to the yarn by a cylindrical cooling device installed so as to surround the strip, and further entangled. The method for producing an ultrafine polyamide multifilament yarn is characterized by being wound around a winding device at a high speed of 3500 to 5000 m / min. 2. The method for producing an ultrafine polyamide multifilament according to claim 1, wherein the oil supply method is such that the first-stage oil supply is performed after cooling, and further the second-stage oil supply is performed after confounding. As a water-containing oil agent, the oil supply amount of 25% by weight or more is supplied with respect to the polymer discharge amount, and then the first-stage oil supply is performed. The method for producing an ultrafine polyamide multifilament according to claim 2, wherein the second stage of oil supply is performed. The spun yarn is divided into two or more parts, and the first stage of oiling is performed. Then, the yarns are combined and then entangled as one thread, and then the second stage of oiling is performed. The method for producing an ultrafine polyamide multifilament according to claim 2. The method for producing an ultrafine polyamide multifilament according to any one of claims 1 to 4, wherein the oil supply after cooling is performed at a position of 400 to 1800 mm from the spinneret. Lubrication after cooling is applied by an oiling guide, the diameter of the circle drawn by the nozzle holes arranged on the circumference is a (mm), the interval between the oiling guides is b (mm), and the number of divided yarns is n Wherein a, b, and n are in the relationship of the formula 1 / (n + 1) ≦ b / a ≦ 1 / n, Filament manufacturing method. Spinneret with discharge holes arranged circumferentially, cylindrical cooling device installed so as to surround the spun yarn, first-stage oil supply device, entanglement imparting device, and second-stage And a polyamide multifilament yarn melt spinning apparatus in which at least a pair of godet rollers and a winding device are sequentially arranged from the upstream side of spinning. The melt spinning of the polyamide multifilament yarn according to claim 7, wherein the first-stage oil supply device is an oil supply guide, and an oil agent discharge hole position of the oil supply guide is in a range of 400 to 1800 mm with respect to a lower surface of the spinneret. apparatus. The polyamide multifilament according to claim 7, wherein the first-stage oil supply device is an oil supply guide, and an oil agent discharge hole position of the oil supply guide can be arbitrarily changed within a range of 400 to 1800 mm with respect to the lower surface of the spinneret. Yarn melt spinning equipment.

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