JPH07109614A - Method for melt-spinning ultrafine multifilament and device therefor - Google Patents

Abstract

PURPOSE:To provide a method for melt-spinning ultrafine multifilaments free from the breakage and fineness irregularity of the multifilaments by cooling and solidifying the spun multifilaments in a good state, and to provide a device used therefor. CONSTITUTION:The device is applied to a spinning device equipped with four spindles. The cooling control means 4 of the spinning device is composed of five dividing plates 9 and three plates 10A-10C for controlling accompanied gas flows. In the accompanied gas flow controlling plates 10A-10C, openings 11 through which the spun yarns can pass from the upper side to the lower side are disposed. Among the accompanied gas flow-controlling plates 10A-10C, that disposed at the highest end plays a role for preventing that a cooling air blown out from a cooling air-blowing device 5 is blown into a region to disturb the atmospheric temperature of the region, the atmospheric temperature in the region being controlled with a gradually cooling means.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for melt spinning ultrafine multifilament yarn.

[0002]

2. Description of the Related Art Generally, ultrafine fibers made of thermoplastic polymers such as polyester and nylon, especially fibers having a denier of 0.1 denier or less, are used as materials for high value-added products such as artificial leather and high-quality clothing. In producing such ultrafine fibers, a method is used in which a molten thermoplastic polymer is cooled by cooling air flowing in a direction that traverses a spun yarn group discharged from a spinneret, drawn and drawn. Such ultrafine fibers are required to have a single yarn fineness of 1.0 denier or less and a multifilament fineness of 20 denier or more. Therefore, in order to produce such ultrafine fibers, it is essential to use a multi-hole spinneret for spinning.
Moreover, in recent years, there has been an increasing demand for improvement in production efficiency, and it has become popular to manufacture a multi-threaded ultrafine multifilament yarn group using a plurality of multi-hole spinnerets.

However, in such multi-hole spinning of multi-fine ultrafine fibers, uneven cooling is likely to occur in the process of cooling and solidifying the spun yarn. This non-uniform cooling causes variations in physical properties among the individual filaments that make up the multifilament yarn, and causes process troubles such as yarn breakage, fineness unevenness in the length direction, and dye unevenness. It was difficult to obtain extra fine multifilament yarn with sufficient quality.

In order to solve such problems, various studies have heretofore been made. For example, Japanese Patent Laid-Open No. 4-18
In Japanese Patent Publication No. 107, the polymer discharge hole arrangement of the spinneret is devised to eliminate the cooling difference between the spun yarns on the blowing side and the non-blowing side of the cooling air, and at the same time, the cooling air passes between the spinning yarns. It has been proposed to eliminate the uneven cooling by improving the passage of the cooling air so that the air can easily pass. However, this method does not take into consideration the increase in the accompanying air flow due to the increase in the number of holes and the occurrence of fineness unevenness caused by the yarn sway caused by the increase. The above-mentioned yarn swaying becomes remarkable especially in multi-hole spinning with 90 holes or more.

Further, in Japanese Patent Laid-Open No. 63-145407, a straightening vane is arranged along the traveling direction of the yarn group to eliminate the turbulence of the cooling air, thereby cooling the yarn group. A method has been proposed for homogenizing and eliminating fineness unevenness of the multifilament yarn. However, even in this method, the yarn swaying induced by the increase in the accompanying air flow due to the increase in the number of holes and the ease of passage of the cooling air between the single yarns are not taken into consideration. It was not enough to reduce the outbreak.

[0006]

The present invention has been made in view of the above problems, and the problems to be solved by the present invention are mainly as follows.

(1) Suppressing the occurrence of yarn sway by effectively controlling the accompanying airflow that increases with multi-hole spinning of ultrafine multifilament yarn.

(2) In order to eliminate the non-uniform cooling of the yarn group on the blowing side and the non-blowing side of the cooling air and the occurrence of yarn sway due to the disturbance of the cooling air, the passage of the cooling air between the single yarns is eliminated. To improve.

(3) Stable and excellent spinning of a multi-threaded ultrafine multifilament yarn group.

[0010]

In order to solve these problems, the present invention provides the following means.

That is, after the spun yarn group is cooled and solidified by cooling air flowing in a direction that traverses the spun yarn group, the spun yarn group is taken out and the single yarn fineness after the take-up is 10 denier or less. In the melt-spinning method for obtaining a multi-filament extra fine multi-filament yarn group consisting of multi-filaments having 90 or more filaments, melt-spinning is performed under the condition that at least the following requirements a to d are simultaneously satisfied. A method for melt spinning ultrafine multifilament yarn is provided. a. Partition each spindle for 100 mm or more along the running direction of the spun yarn group. b. Flowing cooling air across the spun yarn group and along the partition direction. c. In the partitioned area, along the running direction of the spun yarn group, in a plane substantially perpendicular to the central axis of the spun yarn group along the running direction of the spun yarn group. The associated airflow should be controlled at at least two points at intervals.

Further, in order to obtain a multi-filament extra fine multifilament yarn group consisting of multifilaments having a single yarn fineness of 10 denier or less and a filament number of 90 or more after the take-up of the spun yarn, it flows in a direction across the spun yarn group. In a spinning tube for blowing cooling air to cool and solidify the spun yarn group, at least the following requirements a to c, that is, a. The cooling air is provided in parallel along the traveling direction of the spun yarn group in order to separately flow for each weight in the direction crossing the spun yarn group, and A partition plate having an overall length of 100 mm or more measured along the running direction of the yarn group, b. At least 2 arranged substantially perpendicular to the central axis of the spun yarn group along the direction in which the spun yarn group runs.
At least one associated airflow control plate, c. The associated airflow control plate is provided with cooling control means capable of passing through the spun yarn group and having an opening formed near the spun yarn group. A melt spinning apparatus for extra-fine multifilament yarns is provided.

[0013]

Embodiments of the present invention will be described in detail below with reference to the drawings, but it goes without saying that the present invention is not limited to these embodiments.

FIG. 1 is a schematic diagram of a melt spinning process exemplifying the present invention. 1 is a spinning pack, 2 is a multi-hole spinneret, 3 is slow cooling means, 4 is cooling control means, and 5 is cooling. An air blowing device, 6 is a duct, 7 is an oil agent applying device, and 8 is a yarn focusing guide. In FIG. 1, the molten thermoplastic polymer is discharged from a multi-hole spinneret (2) arranged in a spin pack (1). In this way, the spun yarn group (Y) is gradually cooled by the slow cooling means (3) while being spun from the cooling air blowing device (5) in the direction of the arrow in FIG. It is cooled and solidified by the cooling air blown across (Y). Then, after the oil agent is applied by the oil agent applying device (7), it is focused by the yarn focusing guide (8) and taken out. At this time, the cooling air blown from the cooling air blowing device (5) across the spun yarn group (Y) is rectified by the cooling control means (4) so that nonuniform cooling does not occur. And the associated airflow generated as the yarn group travels is suppressed.

Here, it is important that the cooling control means (4) has a total length of 100 mm or more, preferably 300 mm or more along the running direction of the yarn group. When the length of the cooling control means (4) is less than 100 mm, the cooling air control is performed only up to the distance where the cooling control means (4) exists, and therefore the control of the cooling air of the spun yarn group is performed in the initial stage. Only done. For this reason, yarn swinging is induced in a portion where the cooling control means (4) does not exist, and fineness unevenness or the like occurs.

FIG. 2 is a perspective view illustrating the cooling control means (4).

This FIG. 2 is applied to a spinning machine with four spindles, and the cooling control means (4) includes three partition plates (9) and three associated air flow control plates (10A to 10A). 10C
) And two end plates (12). Here, the partition plate (9) is arranged in the running direction of the spun yarn group in order to allow the cooling air to separately flow through the spun yarn group in a direction traversing the spun yarn group. They are provided in parallel along the length direction. The associated airflow control plate (10A to 10C) is provided with an opening (11) through which the spun yarn group (Y) can pass in a downward direction from the top of FIG. . Here, in the associated airflow control plate (10C) provided at the uppermost end of FIG. 2, the cooling air blown out from the cooling air blowing device (5) causes the slow cooling means (3).
It also serves to prevent the ambient temperature from being disturbed by flowing into a region where the ambient temperature is controlled.

The associated air flow control plate (10A to 10C)
Is installed in the vicinity of the yarn group, and is therefore provided to separate the associated airflow that is generated around the yarn group as a result of the yarn group traveling at high speed. Therefore, with this associated air flow control plate (10A-10C),
The associated airflow can be separated before the associated airflow generated around the yarn group has fully developed. This accompanying air flow control plate (10A
-10C), it is necessary to install at least two sheets at intervals shorter than the run-up distance at which the associated airflow develops sufficiently as the yarn group travels. The attached angle of the associated airflow control plate (10A to 10C) may be substantially perpendicular to the central axis of the spun yarn group along the traveling direction of the spun yarn group.

Next, the operation of the partition plate will be described.

In general, in multi-spindle spinning, the cooling air blown out from the cooling air blowing device (5) has a difference between the double-ended weight and the central weight. That is, the wind velocity distribution has a low wind velocity at both ends and a high wind velocity at the center. This phenomenon becomes extremely large when there is no partition plate (9) for partitioning the weights. This is because the partition plate (9) acts as a resistance body against the cooling wind which is a viscous fluid. Therefore, when only the end plates (12) provided outside the weights at both ends are used and the partition plate (9) is not provided for each weight, the end plates (13) serve as resistors at both ends. The wind velocity of the cooling air in the portion is slow, and the wind velocity distribution is high in the central portion where the partition plate (9) which is a resistor does not exist in the central portion. Therefore, by evenly installing the partition plates (9), it is possible to make the wind velocity distribution uniform.

The following experiments were carried out using the apparatus and method described above.

Polyethylene terephthalate chips having an intrinsic viscosity of 0.64 were melted at a temperature of 284 ° C. and spun at a take-off speed of 2800 m / min using a spinneret having a polymer discharge hole diameter of 0.15 mm and 96 holes. Then, drawing was carried out at a draw ratio of 1.61 to obtain a raw yarn of 70 denier (single yarn denier about 0.7).

[0023]

[Table 1]

The results obtained at this time are shown in Table 1 together with the cooling conditions. In addition, as an evaluation standard of the stain, ⊚: extremely good, ◯: good, Δ: slightly uneven, and X: large spot. Here, Examples 1 to 3 in Table 1 are cases in which the partition plate (9) for each of the weights is provided, and based on the case where the one-stage associated airflow control plate (10A) is provided, It is an experimental result under the condition that the second stage associated airflow control plate (10B) at a distance B shown in FIG. 2 from the upper end position of the associated airflow control plate (10A) was attached. As you can see from this table,
The total length of the cooling control means (4) (distance in FIG. 2; A) is 100.
If it is less than mm, as shown in Comparative Example 1 (A = 50 mm), it is markedly inferior to Examples 1 to 3 in any of fineness unevenness, dye unevenness, and yarn breakage ratio, and there is no effect. I understand. Therefore, the total length (A) of the cooling control means (4)
Needs to be 100 mm or more.

Next, Examples 4 to 6 in Table 1 are Examples 1 to
In addition to the conditions of 3, the first-stage associated airflow control plate (10A
2) is an experimental result when a third-stage associated airflow control plate (10C) located at a distance C shown in FIG. Comparing the results with Examples 1 to 3, providing the associated airflow control plates in multiple stages of three stages rather than two stages is superior to any items such as fineness unevenness, dye unevenness, and yarn breakage rate. In addition, as shown in Comparative Examples 2 to 4,
When each of the weight partition plates (9) was not provided, even if the associated airflow control plates (10A to 10C) were installed, inferior results were obtained in all of the above evaluation items.

[0026]

As described above, it is possible to effectively control the entrained airflow that increases with the multihole spinning of the multi-fine ultrafine multifilament yarn group, and suppress the occurrence of yarn wobbling. Further, it is possible to improve the passage of the cooling air between the single yarns, it is possible to eliminate the uneven cooling of the yarn group and the occurrence of yarn sway due to the disturbance of the cooling air, etc. And, it is possible to obtain a very good multi-filament yarn without breakage, which is a very great effect.

[Brief description of drawings]

FIG. 1 is a schematic diagram of a melt spinning process that illustrates the present invention.

FIG. 2 is a perspective view illustrating a cooling control unit according to the present invention.

[Explanation of symbols] 1 spinning pack 2 multi-hole spinneret 3 slow cooling means 4 cooling control means 5 cooling air blowing device 9 partition plates 10A, 10B, 10c associated airflow control plate 11 opening of associated airflow control plate Y spinning Yarn group A Total length of cooling control means B Installation distance of associated airflow control plate in second stage (mm) C Installation distance of associated airflow control plate in third stage (mm)

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[Procedure amendment]

[Submission date] November 1, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Claim 1

[Correction method] Change

[Correction content]

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0011

[Correction method] Change

[Correction content]

That is, after the spun yarn group is cooled and solidified by cooling air flowing in a direction that traverses the spun yarn group, the spun yarn group is taken out and the single yarn fineness after the take-up is 10 denier or less. In the melt-spinning method for obtaining a multi-fine ultrafine multifilament yarn group consisting of multifilaments having 90 or more filaments, melt spinning is performed under the condition that at least the following requirements a to c are simultaneously satisfied. A method for melt spinning ultrafine multifilament yarn is provided. a. Partition each spindle for 100 mm or more along the running direction of the spun yarn group. b. Flowing cooling air across the spun yarn group and along the partition direction. c. In the partitioned area, along the running direction of the spun yarn group, in a plane substantially perpendicular to the central axis of the spun yarn group along the running direction of the spun yarn group. The associated airflow should be controlled at at least two points at intervals.

Claims (2)

[Claims] 1. The spun yarn group is cooled and solidified by cooling air flowing in a direction traversing the spun yarn group, and then the spun yarn group is taken out, and the single yarn fineness after the take-up is 10 denier or less. In the melt-spinning method for obtaining a multi-filament extra fine multi-filament yarn group consisting of multi-filaments having 90 or more filaments, melt-spinning is performed under the condition that at least the following requirements a to d are simultaneously satisfied. Method for melt spinning ultrafine multifilament yarn. a. Partition each spindle for 100 mm or more along the running direction of the spun yarn group. b. Flowing cooling air across the spun yarn group and along the partition direction. c. In the partitioned area, along the running direction of the spun yarn group, in a plane substantially perpendicular to the central axis of the spun yarn group along the running direction of the spun yarn group. The associated airflow should be controlled at at least two points at intervals. 2. A multifilamentary ultrafine multifilament yarn group consisting of multifilaments having a monofilament fineness of 10 denier or less and a filament number of 90 or more after spinning is taken, and flows in a direction transverse to the spun yarn group. In a spinning tube for blowing cooling air to cool and solidify the spun yarn group, at least the following requirements a to c, that is, a. The cooling air is provided in parallel along the traveling direction of the spun yarn group in order to separately flow for each weight in the direction crossing the spun yarn group, and A partition plate having an overall length of 100 mm or more measured along the running direction of the yarn group, b. At least 2 arranged substantially perpendicular to the central axis of the spun yarn group along the direction in which the spun yarn group runs.
At least one associated airflow control plate, c. The associated airflow control plate is provided with cooling control means capable of passing through the spun yarn group and having an opening formed near the spun yarn group. A melt spinning apparatus for ultra-fine multifilament yarns, characterized in that: