JPH0672321B2 - Melt spinning method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a so-called asymmetric quenching spinning method in which a cooling airflow is blown from one direction to a spun yarn of a thermoplastic polymer, particularly polyester or polyamide, and drawn, and an oil agent is used in a specific device, The present invention relates to a spinning method capable of enhancing the cooling effect and stably producing by imparting at a position.

2. Description of the Related Art In recent years, as melt-spinning technology has advanced, as a measure for improving equipment productivity, research on porosity of a spinneret and high take-up speed has been actively conducted. The present inventors asymmetrically quench fibers of atypical cross section or hollow cross section,
In the method of taking up and spinning at a high speed of more than a minute, 400
When using a die having more than one pore, it was found that the method of applying an oil agent is extremely important for stabilizing spinning,
As a result of earnest research, the present invention has been achieved. When the take-up speed is 3000 m / min or more, the tension due to the frictional resistance between the yarn and the air increases, and it becomes easier to partially draw in the spinning process.
May have a negative impact on quality. Also, when the number of holes is 400 or more, the difference in cooling state is likely to occur between the windward and leeward yarns, resulting in poor quality uniformity.
This may cause the spinning condition to be disturbed.

As a conventional method for applying an oil agent in melt spinning, i) a method in which a yarn is brought into contact with the surface of a roller that is partially immersed in an oil agent and rotates to apply the oil agent, and ii) pores for supplying the oil agent are formed. There is a method of using a V-shaped guide provided at the bent portion to press the running yarn against the pores so that the oil agent flowing out adheres thereto. When the method i) is used, when the number of holes increases to about 400 or more, it is necessary to focus the yarns by the focusing guide between the spinneret and the oil agent applying device, but the take-up speed is 3000 m / min or more. In the above, single yarn fluff is likely to occur due to rubbing between the yarn and the guide, which is not preferable. Another problem is the scattering of oil due to the accompanying air flow. Meanwhile i
In the case of the method i), when the number of filaments is 400 or more, the yarns are concentrated at one V-shaped bent portion, and a fused yarn is generated or a yarn spun out from the hole in the outer periphery of the spinneret. There is a problem that the tension of the yarn becomes large and the single yarn breaks frequently.

In view of such circumstances, the present inventors have accomplished the present invention as a result of diligent research on a melt spinning method which eliminates these drawbacks and enables stable operation.

That is, the present inventors melt-extruded a thermoplastic polymer from a spinneret having 400 or more pores arranged on a plurality of parallel lines, and from one direction orthogonal to the parallel lines formed by the pores of the spinneret. When cooling with cooling air and spinning at a high speed of 3000 m / min or more, the width is 0.05 as an oil agent applying device.
We have found a melt spinning method which is characterized by using a rod-shaped guide having at least one linear slit of .about.0.3 mm.

By the way, in the case of performing such asymmetrical rapid spinning, the rod-shaped guide is installed so as to be orthogonal to the traveling direction of the yarn, and the length of the slit of the rod-shaped guide and the installation position are as described in (1) and (2) below. It is necessary to satisfy the formula.

Where x is the length of the rod guide slit (cm) y is the distance from the spinneret to the rod guide (cm) H is 400 or more in the number of spinneret holes and the slit width of the rod guide is 0.05 to 0.3 m in the present invention.
Although m is set to be less than 0.05 mm, the outflow amount of the oil agent is small and the target oil agent application rate cannot be obtained, and increasing the oil agent concentration undesirably causes clogging of the oil agent in the slit portion. Further, if it exceeds 0.3 mm, the oil agent does not flow out uniformly from the slit, unevenness of the oil agent occurs, and roller wrapping easily occurs, which is not preferable in terms of operation stability.

When the length of the slit is less than 0.004 Hcm and the number of spinneret holes which the present inventors are aiming for is 400 or more, nesting fluff is generated in the rod-shaped guide portion due to sticking spots of oil agent or over-squeezing of threads. Easier to do. Conversely, the slit length is 0.04Hc
If it is longer than m, it is difficult to uniformly attach the oil agent, and the oil agent is scattered, which is not preferable. In particular, to prevent the oil agent from scattering, both ends of the guide are U-shaped,
It is preferable to provide a curved L-shape to prevent scattering.

Next, the oiling position is from the spinneret surface in the yarn running direction. It is necessary to keep the above distance.

If the distance is shorter than the above value, the yarn is not sufficiently cooled and solidified, so that not only the fineness unevenness of the yarn becomes large, but also the fused yarn is apt to occur, resulting in deterioration of quality and spinnability. Also, the oiling position If it exceeds, the air resistance of the yarn increases, an excessive spinning tension is applied, and a single yarn breakage or the like is likely to occur, resulting in deterioration of operability.

Next, details of the present invention will be described with reference to the drawings. These drawings are merely examples of the present invention, and the present invention is not limited thereto.

1 (a) and (b) show the state of pore arrangement of the spinneret used in the present invention, wherein the pores are arranged on a plurality of parallel lines. FIG. 2 is a schematic view showing an embodiment of the spinning take-up device used in the present invention. The yarn 2 discharged from the spinneret 1 passes through the cooling zone 3 and is brought into contact with the rod-shaped oiling device 4 after being cooled and solidified, and the oil agent is applied thereto. In this case, it is desirable to use the auxiliary guide 5 so that the oil agent is evenly attached. Furthermore, it is more preferable to use a rod-shaped oiling device instead of the auxiliary guide. After that, it is guided to the focusing guide 6. The yarns bundled into one aggregated yarn by these guides are taken by the godet roller group 7 at a predetermined take-up speed, separated by the final nipple roller 8 from the godet roller group, and then stored. It is stored in Kens 9.

FIGS. 3A to 3C show an example of a rod-shaped oiling guide used in the present invention. These oiling guides preferably use ceramic members in order to prevent yarn breakage and fuzzing, but the present invention is not particularly limited to the members to be used. The ceramic member is preferably made of, for example, aluminum oxide having excellent wear resistance and a purity of 90% or more, but the surface of the metal may be coated with the ceramic member, or another hardening material may be used. The surface roughness is preferably 0.4 to 4.0 μ finish.

In the present invention, if the yarn discharged from the spinneret is sucked into the saxon gun, an oiling device installed at a predetermined position, then an auxiliary guide, a focusing guide, a godet roller group, and a nip roller are introduced in this order. Good.

Next, the effects of the present invention will be specifically described with reference to examples. The quality of the test results was comprehensively judged from 1) the adhesion efficiency (scattering) of the oil agent, 2) the occurrence of yarn breakage during spinning, 3) the occurrence of fluff, and 4) the occurrence of fused yarn. The evaluation was carried out according to the following criteria.

(1) Adhesion efficiency of oil agent ○ -The actual adhesion rate is 95% or more relative to the theoretically applied amount △ -The actual adhesion rate is 94-80% × The-The actual adhesion rate is 79% or less (2) Spinning tone ○ Mark-4 hours In the spinning of No. 1, the number of yarn breaks is 1 or less. △ -The number of yarn breaks is 2 to 5 times X-The number of yarn breaks is 6 or more (3) Occurrence of fluff ○ Mark-Yarn after take-up 120,000 m Fluff test result 1 fluff
Less than or equal to Δ Mark-2 to 9 above-mentioned fluffs-More than 10 above-mentioned fluffs (4) Occurrence of fused yarns ○ -No fused yarn X-There is fused yarn Example 1 Phenols and tetrachlor Polyethylene terephthalate with an intrinsic viscosity of 0.62 measured at 30 ° C using an equal weight mixture of ethane is a three-point support type with an outer diameter of 2.3 mm, a hole area of 28.5 mm ² , and a spinning process with 700 holes. Using a spinneret, spinning was performed at a spinning rate of 295 ° C., a take-up speed of 3800 m / min, and a single-hole denier of 8.3 denier with a single hole discharge rate of 3.5 g / min.

At this time, as shown in Table 1, the oiling device is a two-stage oiling roller, a V-shaped guide, or 0.15 mm.
A rod-shaped guide having slits was used. The position of the oiling and the cooling conditions were fixed to the following conditions and tested.

(1) Oiling position: 250 cm below the spinneret (2) Cooling air blowing position: 30 mm below the spinneret (3) Cooling zone length; 80 cm (4) Cooling air temperature; 24 ° C (5) Cooling air velocity; Table 1 shows the 1.0 m / sec test results. Although not shown in FIG. 2, the application of the oil agent was performed by feeding a predetermined amount from a gear pump through a pipe to a feed port except for the two-stage oiling roller.

Out of the test Nos., Nos. 5 and 6 were within the scope of the present invention, and good results were obtained. On the other hand, test Nos. 1 and 2 are oiling devices as oiling devices, V-shaped guides having pores for applying oil, and Nos. 3 and 4 are rod-shaped guides with slit lengths of 2 cm and 30 cm. Nos. 1, 2, and 3 have low oil adhesion efficiency, frequent fluff and single yarn breakage, poor spinning condition, and test No. 4 In the above, the slit portion of the rod-shaped guide was too long, and the thread was not formed at both ends of the guide, and the oil solution flowed out, so that the predetermined amount of oil solution could not be applied.

Example 2 Polyethylene terephthalate having an intrinsic viscosity of 0.61 measured at 30 ° C. using an equal weight mixed solvent of phenol and tetrachlorethane was used, which was a T-shaped hole type having a pore area of 2.3 mm ² and had a number of holes.
Spinning temperature of 300 ° C and take-up speed of 40 using 495 spinnerets
Spinning at 00m / min, single hole discharge rate 3.55g / min, single yarn denier 8.
2 denier raw yarn was obtained. At this time, the oiling device is 0.1
Using a rod-shaped guide having a slit width of mm with different slit lengths, changing the oiling position, spinning,
Winding was performed.

The cooling conditions were fixed to the same conditions as in Example 1 except that the cooling zone length was 90 cm among the conditions shown in Example 1, and the test was conducted.

The test results are shown in Table 2.

Of the test Nos., No. 7 and No. 10 were the conditions within the scope of the present invention, and showed good spinnability, and the quality of the obtained raw cotton was good with few spots. On the other hand, test No. 8 and 11
However, since the oiling position was out of the range specified in the present invention, single yarn breakage or fluff generation was remarkably difficult to perform spinning. Further, Nos. 9 and 12 were also outside the scope of the present invention, the spinning tension was high, and the spinning tone was poor.

Example 3 Using the same spinneret and spinning conditions as in Example 2, using a rod-shaped oiling nozzle having a slit length of 12 cm and different slit widths, spinning and winding were performed and the results shown in Table 3 were obtained. .

Of the test Nos., Nos. 14 and 15 were conditions within the scope of the present invention, and good results were obtained. On the other hand, Nos. 13 and 16 are cases in which the slit width is out of the range of the present invention, and No. 13 has a narrow slit width and the slit portion is easily clogged, and the oil solution does not flow out. Further, No. 16 has a wide slit width, so that the oil agent does not flow out uniformly from the entire slit portion, and uneven adhesion of the oil agent occurs.

[Brief description of drawings]

FIG. 1, Iro Example of pore arrangement state of spinneret used in the present invention FIG. 2, Schematic diagram showing an embodiment of the spinning take-up device used in the present invention FIG. 3, Example of guide shape used in the present invention ing. 1 ... Spinneret, 2 ... Thread, 3 ... Cooling zone 4 ... Oiling guide 5 ... Auxiliary guide or oiling guide 6 ... Focusing guide, 7 ... Godd roller group 8 ... Nip roller, 9 ... Storage can 10 ... Oiling guide slit

Claims (1)

[Claims] Claim: What is claimed is: 1. A thermoplastic polymer is melt-extruded from a spinneret having 400 or more pores arranged on a plurality of parallel lines, and cooling air is blown from one direction orthogonal to the parallel lines formed by the pores of the spinneret. When it is cooled by, and taken up at a high speed of 3000 m / min or more for spinning, the slit width is 0.05 to 0.3 mm as the oil agent applying device, and the slit length x is 0.004 H ≤ x ≤ 0.04 Hcm between the spinneret hole number H. A method for melt spinning a thermoplastic polymer, characterized in that a rod-shaped guide having at least one linear slit satisfying the above condition is installed so that the distance y from the spinneret satisfies the following formula.