KR100190916B1 - The preparing method of synthetic fiber excellent section and mass change rate - Google Patents

Abstract

The present invention relates to a synthetic fiber having a superior cross section and mass fluctuation rate during the melt spinning process, and a method for manufacturing the same, in particular, to improve the spinning property through uniform cooling and quenching and to improve the cross-sectional change rate between filaments through stabilization of air conditioning. It is for producing high quality synthetic fibers by giving.

Description

Method for producing synthetic fibers having excellent cross-sectional and mass variation and cooling solidification device.

1 is a schematic configuration diagram showing a spinning process applied to the present invention.

2 is a perspective view showing the configuration of a cooling tank applied to the present invention.

3 is a view showing the action of the cooling tank applied to the present invention.

4 is a view showing the operation of the conventional cooling tank.

* Explanation of symbols for the main parts of the drawings

1: spinning cap 2: cooling tank

3: heat insulation block H: total length of cooling tank

L: distance from the front surface of the cooling tank 2 to the filament bundle F to the outermost part of the filament bundle F from the spinneret 1 to the solidification completion point of the filament (the vitrification temperature of each polymer).

L ': distance from the front of the cooling tank 2 to the filament on the outermost side of the filament bundle F after the solidification completion point of the filament (polymerization temperature of each polymer).

F: Filament Bundle B: Height of Upper Cooling Part 2A

The present invention relates to a thermoplastic synthetic fiber having excellent cross section and mass fluctuation rate during the melt spinning process, a method for producing the same, and a cooling solidifying apparatus thereof, in particular, to improve the spinning property through uniform cooling and quenching and to stabilize the filament through air conditioning. By improving the cross-sectional variation of the liver to produce a high-quality synthetic fibers.

In the melt spinning process, a plurality of filaments are also discharged through a molten polymer, and a cooling solidification is performed by blowing a cooling wind in a direction perpendicular to the filament traveling direction in one direction and at the same time depending on the draft ratio due to the winding speed. It is a process that is formed into a fibrous shape as it is refined.

The filament discharged from the mold in the melt spinning process is a viscous viscoelastic fluid to form a thin filament bundle. At this time, by applying a cooling wind to the filament bundle using a cooling tank and cooling and solidifying it, the physical properties are changed from plastic to fiber. In the cooling solidification process of the filament, the cooling wind temperature and the wind speed play an important role in the overall sand formation process. Generally, in order to produce a high quality product having excellent cross-sectional variation, stabilization and uniform cooling of the air conditioning up to the freezing point are required. And quenching play an important role.

However, existing cooling tanks do not have air conditioning stabilization at the top of the cooling tank, which plays an important role in sand formation, and cooling efficiency is lowered. Thus, yarns produced are not only highly varied between filaments but also deteriorated in basic physical properties and product properties. It is getting worse.

In addition, the cooling wind is supplied only in the horizontal direction with respect to one side of the cooling tank, and implies the ultimate problem of asymmetry for each filament.

Due to the interaction of the cooling wind supplied with the filament bundle, there is a non-uniformity in which cooling conditions are not constant for each filament bundle or group within the filament bundle.

This asymmetry and non-uniformity will result in non-uniformity between the filaments in the filament bundle, and this phenomenon is additionally caused by the insulating block present in the lower part of the detention and cooling irradiation, the thermal block is to keep the filament It is the area that minimizes the influence and the formation of the insulating block also plays an important role in the spinning process.

However, the outside block of the insulating block is disturbed by the filament radiated downward.

As the filament is radiated vertically downward, the accompanying airflow destroys the stability of the thermal insulation block, and a certain amount of air must be supplied from the outside air as the amount of air flowed out to the bottom, and the cooling tank takes over the main source of the outside air.

Therefore, the amount of cooling air at the top of the cooling tank is insufficient compared to the amount of cooling air at the bottom of the cooling tank.

In this air-conditioning state, a lot of tension is applied to the spinning filament, and cooling is insufficient in the upper area of the cooling tank, which intensifies factors such as the overall filament's physical properties and the difference in the uniformity between each filament, which increases the cutting frequency and the operability. Was to cause.

On the other hand, there is a solution to increase the wind speed, but there is a limit depending on the thickness of the spinning denier and each filament, so the realization of uniform cooling is quite difficult.

Existing cooling tank 10 is formed vertically in the front and inclined rear to strengthen the cooling air volume in the relatively weak upper part, but even if the speed of the cooling wind is large, the effect is halved when the distance between the cooling tank surface and the filament bundle is wide The actual cooling efficiency is not very large. Even if the cooling wind velocity is increased as much as possible for each filament fineness to strengthen the cooling, if the distance between the filament bundle and the cooling probe is large, the accompanying air flow and cooling air diffusion and insulation block acting as a vertical load. The convection phenomena of the complex cause severe disturbances and cause a difference in crystallization and orientation between the filaments. The mass fluctuation rate and the cross-sectional fluctuation rate increase, resulting in slanting lines as well as mooring.

In addition, when the gap between the filament bundle and the cooling tank is narrowed to increase the cooling efficiency, a lot of cooling winds are accumulated in the lower part, resulting in a lot of tension as shown in FIG. .

The present invention divides the region of the cooling tank around the filament's solidification point, which refers to the vitrification temperature of the poly yoke, to stabilize the air conditioning in the upper region based on the solidification point of the filament to solve the above problems. To reduce the material deviation of the yarn and to improve the cooling efficiency to improve the quenching and uniform cooling performance.In the lower area, it plays the role of returning the filament yarn and maintaining proper tension. It is to improve the quality and to reduce the gap of the deviation of physical properties.

In addition, another object of the present invention is to provide a thermoplastic synthetic fiber having a cross sectional variation of 3% or less and a mass variation of 0.7%, thereby solving defects of fabrics such as salt and salt tea, and having excellent workability in weaving. It is to be able to produce a uniform thermoplastic synthetic fibers with almost no shear cutting.

The structural features of the present invention are as follows.

The thermoplastic synthetic fiber refers to a filament produced by melt spinning a thermoplastic resin such as polyester and polyamide (nylon-6, nylon-66, nylon-46) and the like having polyethylene terephthalate as the main repeating unit.

In the case of general clothing materials, the length of the cooling tank is about 150cm and ranges from 100 to 200cm depending on the fineness and denier. The cooling wind speed is 0.3 ~ 0.6m / s, and the cooling wind temperature is 19 ℃. From the spinneret 1 to the solidification completion point (the vitrification temperature of each polymer) of the filament, the distance L from the filament on the outermost side of the filament bundle F at the front of the cooling tank 2 is In this way, even if the cooling wind speed is low, sufficient cooling effect and stability of thread can be achieved.

However, if the distance of (L) is too long, it will lead to a decrease in turbulence and cooling efficiency, so that the cross-sectional fluctuation rate and mass fluctuation rate of the thermoplastic fiber become large, and the filament needs to be kept within 10 cm until the completion point of the filament. The shorter the angle of the filament is brought to the front of the cooling tank (2) becomes larger and at the same time under the influence of the outside air to come into contact with the insulating block (3) directly below the spinneret (1) is practically impossible to spin. .

On the other hand, after the filament has solidified, the stabilization of the apostle and the provision of proper tension play an important role, which should avoid the distortion of the apostle as shown in FIG. 4. It is necessary to return to the center, and for this purpose, the front shape of the cooling tank 2 is unevenly configured, that is, the lower part of the cooling tank 2 is installed inwardly relative to the upper part of the cooling column 1, and the yarn thread is inserted into the spinneret. Return to the central position of (1) to keep the thread in P-shape.

To this end, the upper part is configured to protrude as long as 3 cm or more and 7 cm or less than the lower part.

On the other hand, from the filament after the freezing point, the distance (L ') from the filament bundle (F) to the front of the cooling tank 1 is set to extend to 3 cm or more and 7 cm or less with respect to the distance (L) in the freezing point, To this end, the front shape of the cooling tank 2 is unevenly constructed so that the upper cooling portion 2A is applied to the filament within the freezing point on the upper side of the cooling tank 2, and the lower cooling is applied to the filament after the freezing point on the lower side. The part 2B is divided into two parts, and in order to satisfy the distance L (L '), the upper cooling part 2A protrudes by 3 cm or more and 7 cm or less than the lower cooling part 2B. It is composed of the state.

If the distance L 'is greater than 7 cm, the difference between the filament bundle and the focal point position is increased, resulting in severe distortion of the apostle, and additionally due to excessive tension rise When the distance L 'is less than 3 cm, the filament bundles from the upper part are excessively blown out to the front of the cooling tank 2 and are brought into contact with the insulating block 3 below the spinneret 1. Will cause.

In addition, small filaments having a denier having a denier of less than 2 denier have a narrow firing point from the spinneret (1), so that a solidification point is formed in the range of 20% or more and 30% of the total length (H) of the cooling tank (2). In the case of the filament having a high single thread fineness, the freezing point is located below the spinneret (1) than the filament having the small fineness, and the freezing point is formed within 30% or more and 40% of the total length (H) of the cooling tank (2). .

Therefore, the height B of the upper cooling part 2A is also set in the range of 20% or more and 40% with respect to the total length H of the cooling tank 2 according to denier.

Conventional solidification point refers to the vitrification temperature of the polymer, which is about 70 ° C. for polyesters based on polyethylene terephthalate and about 50 ° C. for nylon-6 fibers.

The upper cooling part is installed in accordance with the distance of freezing point, and the filament is affected by a small disturbance up to the freezing point, causing distortion.

Therefore, it is imperative to set the stabilization conditions up to the solidification point, and for this purpose, the air conditioner is stabilized by additionally attaching the length of the upper cooling part.

Therefore, if the length of the upper side cooling portion is short, there is a sudden distribution difference of the cooling air before the freezing point.

As a result, the airflow in the economy is severe, and the mass change rate and the cross-sectional change rate may worsen rather than the overall installation.

In terms of test results, the results were reflected as they were, which led to poor operation and increased cooling flow.

On the contrary, when the length of the upper side cooling part is too long, the entire thread is pushed forward.

The lower part of the cooling tank tends to accumulate due to the accompanying air flow as the thread flows, so that the overall advancement forwards by the length of the upper protrusion, so that the entire apostle needs to be modified or remodeled.

Otherwise, the tension is excessively applied to the upper part, that is, the overcooling phenomenon occurs, and due to the excessive tension in the winding part, the drum form (drum form) abnormality, or the radiation guide and the gorodol (G / R) contact is cut off. Frequent

Hereinafter, looking at the superiority of the present invention through a comparative example as follows, the present invention is not limited to the comparative example.

Comparative Example

The thermoplastic polyester resin having an intrinsic viscosity of 0.67 was measured at a spinning temperature of 290 ° C. while changing the shape of the cooling bath as shown in FIG.

The spinning flux was 3,000m / min, the total cooling tank length is 110cm, the wind speed of the supplied cooling wind is 0.45m / s, the cooling wind temperature is 19 ℃, the final drawn yarn 120 denier 36 filament.

As a comparative example, a spinning test was performed under the same conditions using a general cooling bath.

The mean values and the deviations of the physical properties of the feed produced under each condition are as follows.

a: Length which the upper cooling part 2A protruded with respect to the lower cooling part 2B.

b: Length of upper cooling part.

Here, the analysis tools and methods used for the physical property analysis are as follows.

※ Elongation: It is an universal testing machine, which is measured 5 times per sample and 10 times or more (INSTRON).

※ Mass variation rate: Measure the mass change of the sample at the speed of 25m / min with Uster value for 3 minutes. Perform at least 10 times to get the average value.

※ Section Variation Rate: The image filament cross-sectional area is calculated by Image Analyzer to find individual deviation. Do this 10 times or more to determine the average value.

Claims (3)

Melting and spinning thermoplastic synthetic resins to produce thermoplastic fibers; Cooling distance (L) in the upper portion of the cooling unit is less than 3cm shorter than the cooling distance (L ') of the lower portion of the cooling of the molten spinning cooling tank characterized in that the thermoplastic synthetic fibers with excellent cross-sectional and mass variation rate Manufacturing method. The method of claim 2, wherein the thermoplastic synthetic resin is melt-spun and then cooled and solidified to produce a thermoplastic synthetic fiber; The upper and lower cooling parts 2A and 2B are separately formed on the front side of the cooling tank 2, and the upper cooling part 2A protrudes by 3 cm or more and 7 cm or less in length than the lower cooling part 2B. From the detention (1) to the filament solidification completion point (the vitrification temperature of each polymer), the distance (L) from the front of the upper cooling section (2A) of the cooling tank (2) to the filament bundle (F) is within 10 cm, The height B of the upper cooling section 2A is less than or equal to 2 denier less than 20% of the total length H of the cooling tank 2, and the single degree of fineness is 2 denier or more and the upper cooling section 2A is less than 2 denier. ) If the height (B) is less than 60cm, 30% or more and less than 40% of the total length (H) of the cooling tank (2) characterized in that the excellent cross-section and mass variation. In the cooling solidification apparatus of the thermoplastic synthetic fiber; Cooling solidification apparatus of the thermoplastic synthetic fiber, characterized in that the upper cooling portion (2A) is 3 to 7cm bulge than the lower cooling portion (2B).