JPS6141314A - Method of melt spinning using spinneret with many holes - Google Patents

Abstract

PURPOSE:To set a drawing speed in a specific range, and to cool effectively extruded yarn in a cooling column, by controlling a feed amount of the outside air of a ring-shaped suction column of a cooling column and an exhaust amount of exhaust from an exhaust column in such a way that a specific relationship is satisfied. CONSTITUTION:The ring-shaped suction column 1 of the outside air, the natural suction column 3 of the outside air, and the exhaust column 4 are set below the face of a spinneret having 1,000-4,000 holes, and the air flow accompanying yarn is removed by the blocking plate 6. The feed amount Y of the outside air from the suction column 1 and the exhaust amount Z of exhaust from the exhaust column 4 is controlled in such a way that the relationship 0.5X10<-2>.H<=Y <=0.5X10<-2>.H+700X10 and Y+6<=Z<=Y+10 (H is number of holes of spinneret; units of Y and Z are Nm<3>/min). The drawing speed of the yarn 7 is set in a range of 800-1,500m/min.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a melt-spinning method using a multi-hole spinneret, as typified by synthetic fiber tow, and more particularly, to The present invention relates to a method for stably and effectively cooling the produced yarn to spin a multi-filament yarn with excellent quality and performance without inter-fiber fusion or yarn breakage.

Conventionally, cooling the discharged yarn in melt spinning is a basic means of melt spinning, and many proposals have been made so far. For example, Japanese Utility Model Application Publication No. 55-54370 discloses that stable spinning can be achieved by specifying the installation position of a cooling cylinder during melt spinning. The spinneret used in this Jitsukasho has 10 holes.
If the number of holes is less than 00, there are relatively few problems since the number of single fibers that make up the spun yarn is small, but if the number of holes exceeds 1000, it is necessary to increase the cooling capacity of the cooling tube. If the cooling is strengthened, the occurrence of inter-filament melting and thread breakage will increase rapidly.

In particular, solving the above problem becomes extremely important when increasing the number of holes and increasing the speed at which the discharged yarn is taken up to greatly increase productivity.

Furthermore, in order to prevent troubles in post-processing processes such as stretching and winding after the spinning process, and to process the yarn smoothly after it leaves the cooling cylinder, an oil agent is applied to the yarn. However, in this case, unless the airflow that accompanies the yarn exiting the cooling tube is removed, it will be difficult to stabilize the oil film on the roller and guide surfaces, making it difficult to uniformly apply the oil to the yarn. There is a problem with becoming.

[Problem to be solved by the invention]

The object of the present invention is to have a hole number of 100 or more, especially 100.
When spinning using a multi-hole spinneret in the range of 0 to 4000, it is possible to effectively cool the discharged yarn in the cooling cylinder and prevent fusion between single yarns and yarn breakage for a long time. An object of the present invention is to provide a melt spinning method that enables stable spinning over a long period of time.

Still another object is to effectively remove the airflow accompanying the yarn from the cooling cylinder when applying an oil agent to the yarn exiting the cooling cylinder in the melt spinning, and to make the oil film unstable when applying the oil agent. It is an object of the present invention to provide a method that prevents the yarn from drying out, uniformly applies an oil to the yarn, and facilitates subsequent yarn processing.

Hereinafter, the present invention will be explained specifically and in detail.

[Means for solving problems]

FIG. 1 is a cross-sectional view showing one embodiment of the cooling tube used in the present invention. In the figure, 1 is an annular outside air blowing tube, 2 is a quench air inlet, 6 is a natural outside air suction tube, and 4 is an exhaust tube. ,
5 is a forced exhaust port, 6 is a lower shielding plate, 7 is a thread, and 8 is an oiling roller.

As shown in the figure, the cooling air is guided from the quench air inlet 2 to the annular outside air blowing tube 1, passes through the exhaust tube 4, is forcibly exhausted from the forced exhaust port 5, and is supplied by the natural outside air suction tube 6. The lack of energy is replenished. Further, in this case, the accompanying flow that accompanies the yarn 7 flows out from the lower shielding plate 6, but when this accompanying flow increases, the oil film on the surface of the oiling roller portion 8 is disturbed.

When the melt-spun yarn of the present invention is cooled in a cooling cylinder, the number of holes in the spinneret is increased, especially 100.
In order to effectively cool the yarn discharged from a multi-hole spinneret (0 to 4000 holes) and to prevent problems such as inter-fiber melting and yarn breakage, it is necessary to prevent yarn sway within the cooling cylinder. It is necessary to prevent this. However, in order to improve productivity, when spun yarn is spun at a take-up speed of 800 to 1500 m/min, it causes severe yarn wobbling, fusion between single yarns, and yarn breakage, making it difficult to achieve stable spinning. becomes difficult.

Therefore, as a result of intensive investigation into the causes of yarn wobbling in such high-speed spinning, the present inventors determined that the number of holes in the spinneret used for melt spinning and the amount of air supplied to the annular outside air blowing tube of the cooling tube. (X:Nm3/l;+) and rg
'JAI @, 9t+f＞C-nom "8 tatami (Z
:Nm''/min), and have arrived at the present invention.

That is, FIG. 2 shows the relationship between the number of holes in the spinneret and the amount of cooling air supplied from the annular outside air blowing tube to the cooling tube when melt spinning is performed using the cooling tube shown in FIG. 1 above. As shown in the figure, the vertical axis shows the cooling air volume and the horizontal axis shows the number of holes, and when examining the occurrence of yarn breakage and inter-fiber fusion in the spun yarn, the diagonal lines in the figure It was found that the area in which neither yarn breakage nor fusion occurs is divided into three areas: an upper area where yarn breakage occurs and a lower area where fusion occurs.

In addition, FIG. 3 shows the amount of air discharged from the exhaust pipe, with the horizontal axis representing the amount of air supplied to the annular outside air blowing pipe, in melt spinning using a spinneret with a constant number of holes and using the same cooling pipe. Taking the displacement amount on the vertical axis, changing the take-up speed of the discharged yarn, spinning, and plotting the supply air amount and exhaust amount without causing fusion and yarn breakage, it is found that the take-up speed is 800 m/min. In this case, if the spinning is stabilized when the relationship shown by straight line A in Figure 3 is satisfied, and the take-up speed is 1500 m/min,
When the relationship shown by straight line B in FIG.
/minute, stable spinning is achieved by straight lines A and B in Figure 3.
It turns out that it is shown by the straight line between . 1 more
When the number of holes in the cap was changed and the relationship between the air supply amount, exhaust amount, and take-up speed without thread breakage or fusion was examined in the same way, it was found that a linear relationship similar to that shown in FIG. 3 was shown.

Formula (I) and formula (II) are derived from the relationship shown in FIGS. 1 and 2 above, and formula (I) and (It)
If the condition expressed by is satisfied, the number of holes will be 1000~
4000 spinneret is used, take-up speed is 800~1
Effectively cools the discharged yarn under the conditions of 500 m and 7 minutes,
This enables stable spinning.

The conditions expressed by equations (1) and (I[) obtained from FIGS. 2 and 3, respectively, can be expressed by the shaded area in FIG. 4.

In other words, in Fig. 4, as in Fig. 3, if the horizontal axis is the supply air amount supplied to the cooling cylinder and the vertical axis is the exhaust amount, then the straight lines (A) and (A') can be found using equation (I). The straight lines (B) and (B) indicate the upper and lower limits determined by equation (II), and the straight lines (A), (A'),
If the conditions that satisfy the shaded area surrounded by (B) and (B') are adopted, a multi-hole spinneret with 1000 to 4000 holes is used and the take-up speed is 800 to 1500.
Stable spinning without fusion or yarn breakage can be carried out under conditions of m7 minutes.

Next, in the present invention, using the cooling cylinder as described above,
The yarn melt-spun under the conditions specified by formulas (I) and (n) is treated with an oil agent using guides and rollers to ensure smooth processing in post-processing steps such as drawing and winding. However, in this case, the yarn leaving the cooling tube is accompanied by an accompanying air current, which disturbs the oil film on the guide and roller surfaces, causing uneven oil supply and preventing uniform distribution of oil to the yarn. Applying oil becomes difficult. Therefore, in the present invention, a shielding plate is provided at the bottom of the cooling cylinder in order to effectively strip off the airflow accompanying the yarn, stabilize the oil film on the oiling roller, and ensure uniform oil supply. is preferable.

However, in this case, since the aperture ratio of the shielding plate affects the stripping effect of the airflow accompanying the yarn, it is preferable that the aperture ratio of the shielding plate be within the range of 30 to 50%. Examples of the shielding plate include wire mesh and punched metal, but preferably a shielding plate as shown in FIG. 5 is used.

That is, FIG. 5 is a plan view showing an example of a shielding plate used in the spinning method of the present invention, and in the figure, 10.10
' is a semicircular punching metal, 11 and 11' are guide rods installed in the punching metal, 12 is a slit, and 13 is a gear for opening and closing the punching metal. A slit 12 is formed through which the strip passes. By attaching such a shielding plate to the lower end of the cooling cylinder, the airflow accompanying the yarn can be effectively removed when the yarn passes through the slit of the shielding plate.

〔effect〕

According to the present invention, when melt-spinning a polymer using a multi-hole spinneret with 1,000 to 4,000 holes and at a high take-up speed of 800 to 1,500 m7, the spinnability is extremely stable and the fusion bond is stable. It is possible to manufacture multi-filament yarn with excellent quality and performance without yarn breakage or yarn breakage with high productivity.

Furthermore, when applying oil to the yarn immediately after spinning, it is possible to stabilize the oil film on the oiling port and make the oil supply uniform, so there is less uneven oil adhesion to the yarn, and the post-processing process Since the processing is stabilized, there are no problems such as uneven stretching, wrapping, and fuzz, and production is stabilized, and at the same time, the quality of the product can be improved and stabilized.

The present invention will be explained below with reference to Examples.

Example 1 Polyethylene terephthalate having an intrinsic viscosity of 0.63 was spun at a spinning temperature of 290°C using a melt spinning apparatus equipped with a cooling cylinder as shown in FIG.

In this case, as shown in Table 1, the number of holes in the spinneret,
The discharge rate (7/min), the take-up speed (m/min), the supply amount of cooling air supplied to the annular outside air blowing tube, that is, the supply air amount (N
m3/min) was changed to examine the fusion and breakage of the threads led out from the cooling cylinder. The results are shown in Table 1.

Note that fusion was expressed as the number of times fusion occurred per minute, and yarn breakage was expressed as the number of times yarn breakage occurred per minute.

From the table, 7g63.4-. 5, 6, 7, 11. 12 and 15
In all cases, there was no problem of fusion or yarn breakage, and stable spinning was possible.

(Margins below this page) Example 2 In Example 1, the number of metal holes was 2277, the discharge rate was 11341/min, the take-up speed was 910 m7 min, and the cooling air volume and exhaust volume were as shown in Table 2. The fusing of the discharged yarn and the number of yarn breakages were investigated. The results are shown in Table 2.

A1 satisfying the conditions specified in formulas (I) and (II)
No. 8, 19, 22, and 23 all showed stable spinnability with no fusion or yarn breakage.

(Margins below this page) Example 3 In Example 2, shielding plates with different aperture ratios were provided at the bottom of the cooling cylinder, and only the conditions shown in Table 3 were changed to create Example 2.
The yarn was spun in the same manner as above, and the amount of yarn wobbling in the cooling cylinder and the unevenness of oiling in the oiling were examined. The results are shown in Table 3.

(Margins below this page)

[Brief explanation of drawings]

FIG. 1 is a side sectional view showing an example of a cooling cylinder used in the melt spinning method of the present invention, FIG. 2 is a diagram showing the relationship between the number of holes in the spinneret and the cooling air volume in spinning using the cooling cylinder,
FIG. 3 is a diagram showing the relationship between the displacement amount and the air supply amount in the spinning method using the cooling cylinder, and FIG. FIG. 5 is a plan view showing an example of a shielding plate used in the cooling cylinder of the present invention. DESCRIPTION OF SYMBOLS 1... Annular outside air blowing tube, 2... Cutting chair inlet, 3... Natural outside air suction tube, 4... Exhaust tube, 5...
...Exhaust port, 6...Shielding plate, 7... Yarn, 8...
Oiling roller, 10.10'...Punching metal, 11°11'...Guide rod, 12...Slit, 16...Gear.

Claims (1)

[Claims] 1. When melt-spinning a polymer using a multi-hole spinneret, a ring-shaped outside air suction tube, a natural outside air suction tube, and an exhaust tube are provided below the spinneret surface having 1000 to 4000 holes. A cooling tube is provided, and the amount of air supplied from the annular outside air suction tube (Y) and the amount of exhaust air from the exhaust tube (Z) of the cooling tube are controlled so as to satisfy the following formulas (I) and (II), A melt spinning method using a multi-hole spinneret, characterized in that the yarn exiting the cooling cylinder is taken at a take-up speed within a range of 800 to 1500 m/min. (I) 0.5×10^-^2・H≦Y≦0.5×10
^-^2H+700×10(II)Y+6≦Z≦Y+10 However, in the above formula, H: number of holes in the cap, Y: air supply amount (Nm
^3/min), Z: displacement amount (Nm^3/min). 2. The melt spinning method using a multi-hole spinneret according to claim 1, characterized in that a shielding plate having an aperture ratio of about 30 to 50% is provided on the lower surface of the cooling cylinder.