JPH0660447B2 - High-speed flowing bath wet spinning method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a flow bath wet spinning method. More specifically, it relates to a flow bath wet spinning method for carrying out high-speed spinning to obtain a final product such as a high-quality woven fabric or knitted fabric, which is free from cutting yarns and fluffs and is obtained. Is.

Usually in wet spinning, in order to improve the productivity, in order to increase the spinning speed, the yarn immediately after being discharged from the spinneret is guided to the flow tube together with the flowing coagulating bath, and the yarn accompanying the speed increase Flow bath wet spinning methods are used to reduce the bath resistance to water.

Further, in order to prevent the flow of the strong bath from resisting the acceleration of gravity, the formed yarn and the coagulation bath proceed downward in the flow tube from above, and the flowing bath wet spinning method is directed downward. It is efficient to carry out.

However, in such a method, after the yarn and the coagulation bath exit the flow tube, the yarn is separated from the coagulation bath in order to allow the yarn to travel to a subsequent process such as winding. The cutting thread is taken in the coagulation bath, the filament yarn is taken in the coagulation bath and fluff is generated, and the filament yarn is taken in the coagulation bath and not cut until it is partially cut. There was a drawback that it was stretched to the end and single yarn talumi was generated.

Such drawbacks appear in many wet spinning methods, with the exception of cupraammonium cellulose stock solution having self-adhesiveness of single yarn, and aim at high speed operation in order to further improve productivity. Was an obstacle.

In particular, in the downward-directed flow bath wet spinning method in which the coagulation bath flow after leaving the flow tube is accelerated by the acceleration of gravity, this drawback has been a major obstacle.

Therefore, an object of the present invention is to provide a wet spinning method,
An object of the present invention is to provide a spinning method capable of suppressing the generation of cutting yarns, fluffs, and slack in a single yarn and achieving high-speed spinning with high productivity.

That is, the inventors of the present invention guide the yarn immediately after formation discharged from the spinneret into the flow tube together with the coagulation bath, and let out a part of the coagulation bath flowing downward from the side surface of the flow tube. Found to be achieved by reducing the amount of coagulation bath flow after exiting the flow tube and by suppressing the yarn and single yarn from being taken up in the coagulation bath when separating the yarn from the coagulation bath. It was

When attempting to achieve a higher spinning speed, it is necessary to reduce the bath resistance of the coagulation bath given to the yarn immediately after formation. For this purpose, the relative speed of the yarn traveling in the coagulation bath and the coagulation bath must be reduced. Need to lower. Therefore, as the spinning speed increases, the coagulation bath flow rate must be increased. This results in defects such as cutting threads and fluff when separating the yarn from the coagulation bath flow after exiting the flow tube.

The disadvantages of separating the yarn from the coagulation bath stream at the outlet of the flow tube are:
Although it depends on the flow rate of the coagulation bath at the outlet, it was qualitatively found to be remarkable as the flow rate of the coagulation bath increased.

On the other hand, in order to increase the speed of the coagulation bath flow and reduce the flow rate of the coagulation bath, there is a method of reducing the flow tube diameter. In consideration of preventing the yarn from coming into contact with the inner wall of the flow tube while swaying, there is a limit to the minimum value of the inner diameter of the flow tube in industrial production, which is usually 3 mmφ, which is the flow rate associated with high-speed spinning. No method has been found for smoothly separating the yarn and the coagulation bath at the tube outlet.

For the first time, the method of the present invention makes it possible to smoothly achieve the separation of the yarn from the coagulating bath flow at a high speed and at the outlet of the flow tube.
That is, the gist of the present invention is that in a flow bath wet spinning method using a flow tube, a flow tube in which a plurality of bilaterally symmetrical holes are bored downward toward the outside at a point near the outlet on the side surface of the flow tube. A high-speed flowing bath wet spinning method is characterized in that one is used.

According to the method of the present invention, by using one flow tube in which a plurality of symmetrical holes are perforated downward and outward at a point near the outlet on the side surface of the flow tube, the flow tube outlet at the time of high-speed spinning is used for the first time. The yarn and the coagulation bath can be smoothly separated.

Hereinafter, the present invention will be described in detail.

In the present invention, the coagulation bath is flowing under pressure in the flow tube, and a part of the coagulation bath is flowed by using a flow tube with a hole having a predetermined diameter on the side surface at a point near the outlet of the flow tube. It can be leaked out.

Also, when using a flow tube with perforated holes, the number of holes must be symmetrical and plural. This is because in the case of a single hole, the coagulation bath flow in the flow tube is unbalanced, the yarn running in the flow tube is shaken, and hits the inner tube of the flow tube to generate fluff.
The number of the holes is usually about 2 to 4, but may be up to about 12 depending on the case.

Also, the vertical position where the side surface of the flow tube used is drilled is
It is preferable to be as close as possible to the outlet of the flow tube, which is as far away from the spinneret as possible. This is because at a point farther from the spinneret, the coagulation of the yarn progresses, the structure of the yarn becomes stronger, the turbulent flow of the coagulation bath generated near the perforated part of the flow tube, and the perforated part of the flow tube. This is because the structural destruction of the yarn does not occur due to the increased bath resistance of the coagulation bath flow that occurs thereafter. The holes to be drilled are directed outward and downward with respect to the axis of the flow tube, but the angle of the holes may be set appropriately. The angle is preferably 45 degrees or less.

Further, in some cases, a method of using a flow tube having a reduced inner diameter of the flow tube from the portion formed on the side surface of the flow tube to the outlet of the flow tube is also preferable. In this method, since the flow velocity of the coagulation bath in the flow tube cannot be reduced even after the perforated portion of the flow tube, structural breakdown of the yarn due to bath resistance does not occur. In addition, since the yarn can be pulled out from the outlet side of the flow pipe with a yarn guide jig such as wire when starting operation, use a flow pipe with a small inner diameter, for example 3 mmφ or less, only near the outlet of the flow pipe. What you do will not hurt.

Next, an example of an embodiment of the conventional method and the method of the present invention will be described with reference to the drawings.

FIG. 1 is a diagram showing a conventional flow bath wet spinning method. The yarn 2 discharged from the spinneret 1 is guided to the flow tube 3 together with the coagulation bath whose arrow 7 indicates the inflow direction. The yarn 2 exiting the flow tube 3 is separated from the coagulation bath flow 4, travels in the direction indicated by the arrow 5, and proceeds to a subsequent step (not shown) such as winding.
The vicinity of the spinneret is covered with a casing 6. A yarn path 8 is used at the separation point between the yarn 2 and the coagulation bath.

The dotted line 9 indicates that the yarn or the single yarn is
It shows a state that the coagulation bath flow 4 is about to be applied, and this gives cutting yarns, fluffs, and loose yarns to the yarns.

FIG. 2 is a diagram showing an example of the flowing bath wet spinning method of the present invention. The yarn 2 discharged from the spinneret 1 is guided to the flow tube 3 together with the coagulation bath whose arrow 7 indicates the inflow direction. A flow tube is used in which two holes 10 and 11 are bored downward at the tip of the flow tube 3. The holes 10 and 11 are bored at an angle of 30 degrees with respect to the axis of the flow tube 3. Hole 1
0 and a part of the coagulation bath in the flow tube flow out from the hole 11 as coagulation bath flows 12 and 13, respectively. The yarn 2 exiting the flow tube 3 is separated from the coagulation bath flow 4, travels in the direction indicated by the arrow 5, and proceeds to a subsequent step (not shown) such as winding. The vicinity of the spinneret is covered with a casing 6, and a yarn path 8 is used as a separation point between the yarn 2 and the coagulation bath.

According to the method of the present invention, even when the yarn or the single yarn is operated by the conventional method under the condition of being taken in the coagulation bath flow 4, such a defect is not observed.

FIG. 3 is a view showing a flow tube which is used in the method of the present invention and which is perforated on the side surface and whose flow tube diameter below the perforated portion is narrowed. Reference numeral 3 denotes a flow tube, and holes 14 and 15 are bored on the side surface thereof, and the diameter of the flow tube 3 is narrowed at 16 below the hole.

Hereinafter, the present invention will be described in more detail with reference to Examples.

Example Flow bath wet spinning was performed using viscose. The viscose used contained 6% by weight of cellulose and 8% by weight of caustic soda. As a coagulation bath, sulfuric acid 140g /
An acid solution of 52 ° C. containing 260 g of sodium sulfate and 15 g of zinc sulfate was used. The spun yarn is 75 denier 2
A 6 filament yarn was spun using the flow tube of the present invention as illustrated in FIG. As a comparative example, the method shown in FIG. 1 was also performed.

The flow tube used was made of glass and had a length of 1.4 m and a thickness of 1 mm.
At the point 20 mm from the bottom, on the same circumference, at the angle of 30 degrees outward and downward with respect to the axis of the flow tube, symmetrically, 4 holes are formed.
It was perforated on the individual side surface. (The non-perforated flow tube was used in the comparative example.) The inner diameter of the flow tube was 3.5 mm and 4 mm, and the 1.0 mm diameter hole was used for the 3.5 mm flow tube and the 4 mm flow tube. Four 1.2 mm diameter holes were used.

Under each condition, the coagulation bath flow velocity in the main portion of the flow tube was kept at a point lower than the yarn running speed by 40 m / min, and the yarn was not taken into the coagulation bath flow at the outlet of the flow tube, the highest spinning speed. I asked.

The results are shown first.

As described above, the maximum spinning speed could be greatly improved by using the flow tube in which a plurality of bilaterally symmetrical holes were drilled at a point near the outlet on the side surface.

[Brief description of drawings]

FIG. 1 is a diagram showing a conventional flowing bath wet spinning method, FIG. 2 is a diagram showing an example of the flowing bath wet spinning method of the present invention, and FIG. 3 is a side surface used in the method of the present invention. It is a figure which shows the flow pipe which was perforated | pierced and was narrowed down the flow pipe diameter below the perforation part. 1 ... Spinner, 2 ... Yarn, 3 ... Flow tube, 4 ... Coagulation bath flow, 5 ... Arrow indicating traveling direction of yarn, 6 ... Casing, 7 ... Coagulation bath inflow direction , Arrow 8 ... Thread path,
9 ... A state in which a yarn or a single yarn is being taken up by a coagulation bath flow, 10 and 11 ... holes, 12 and 13 ... coagulation bath flow, 14 and 15 ... holes, 16 ... Squeezed part

Claims (2)

[Claims] 1. A flow bath wet spinning method using a flow tube,
A high-speed flow bath wet-spinning method, characterized in that one flow tube having a plurality of bilaterally symmetrical holes perforated outwardly at a point near the outlet on the side surface of the flow tube is used. 2. The high-speed flow bath wet-spinning method according to claim 1, wherein a flow tube whose diameter is narrower than the position where the holes are drilled is used.