JPH0343362B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a spinneret, and more particularly to a method for producing a spinneret for wet spinning having a large number of fine spinning holes and made of Ta.

Traditionally, yarns obtained by wet spinning include acrylic,
There are staple fibers such as rayon, and the material of the spinneret used in the wet spinning method is, for example, stainless steel in the case of acrylic, and precious metals such as Ta, Pt, and Au in the case of rayon.

By the way, there are various methods for forming a large number of fine spinning holes in such a spinneret material, but for example, in the case of electrical discharge machining or cutting, the walls of the resulting spinning holes are extremely rough; During spinning, the stock solution accumulates and sticks to the unevenness of the wall surface, causing scratches on the surface of the spun yarn. Therefore, the yarn is of poor quality such as uneven coloring during dyeing.

For this reason, the spinning hole of the spinneret requires a very smooth wall surface, and therefore, many fine spinning holes are often formed in the spinneret material by a plastic working method using a punch tool.

However, even with this plastic working method, there are problems, especially when the material of the spinneret is made of Ta. As shown in Fig. 1, when the stock solution discharge holes 4 are punched at the bottom of the stock solution introduction hole 2 made in the spinneret material 1 using the punch tool 3, the number of stock solution discharge holes 4 will be approximately 1,000 to 2,000. Vertical streak-like scratches occur on the wall surface, and the scratches gradually become larger, and due to these scratches, the stock solution discharge hole 4, especially near its exit, becomes a multi-acicular hole 4' with many jagged edges as shown in Fig. 2. .

The reason why the raw solution discharge hole 4 becomes a multi-needle-shaped hole 4' is that the spinneret material 1 melts and adheres to the punch tool 3 due to friction generated between the spinneret material 1 and the punch tool 3 during processing. (seizing), deposits grow as the stock solution discharge hole 4 is drilled, and the stock solution discharge hole 4
This is because the wall surface of the spinneret material 1 is scraped.
In the case of Ta, this phenomenon is particularly remarkable.

In order to eliminate this phenomenon, the punch tool 3 should be replaced before drilling 1000 stock solution discharge holes 4, but it is better to replace the punch tool 3 before drilling 1000 stock solution discharge holes 4. In this case, the number of man-hours required is enormous,
This results in a very expensive spinneret, which is not suitable for actual production.

Also, attempts have been made to apply various lubricating oils 5 to the bottom of the stock solution introduction hole 2 as shown in FIG.
When entering the Ta material, the oil film of the lubricating oil 5 is completely cut off as shown in FIG. becomes.

The yarn spun from such multi-needle-shaped holes 4' has vertical flaws, which causes uneven color during dyeing, and in extreme cases, yarn breakage may occur.

The present invention was developed in view of the above circumstances, and can be made without damaging the wall surface of the stock solution discharge hole in a wet spinning nozzle made of Ta material having a large number of fine spinning holes. Therefore, it is an object of the present invention to provide a method for manufacturing a spinneret that can spin yarn of good quality without scratches on the surface of the yarn being spun and without uneven coloring during dyeing.

The method for producing a spinneret of the present invention is as shown in FIG.
After drilling, a Ta oxide film 6 is formed on the wall surface of the stock solution introduction hole 2 by chemical or physical means, and then the bottom of the stock solution introduction hole 2 is formed by plastic working with a punch tool 3 as shown in FIG. 5b. A stock solution discharge hole 4 is provided in the hole.

As described above, in the spinneret manufacturing method of the present invention, the stock solution introduction hole 2 is formed in the spinneret material 1, and the Ta oxide film 6 is formed on the wall surface of the spinneret material 1. When the stock solution discharge hole 4 is bored by plastic working according to step 3, since the coating 6 has good lubricity and low frictional resistance,
Since the spinneret material 1 of Ta of the punch tool 3 is not cut by the punch tool 3,
As it enters the inside, it is stretched and forms a coating 6' on the wall surface of the stock solution discharge hole 4, and since the coating 6' has a high melting point, it does not melt and adhere to the punch tool 3. Therefore, even if the punch tool 3 repeatedly punches the stock solution discharge hole 4, the wall surface of the stock solution discharge hole 4 will not be damaged. In this way, the numerous stock solution discharge holes 4 in the spinneret form smooth walls that follow the shape of the punch tool 3, and the surface of the yarn spun with this spinneret is free from scratches.
There is no color unevenness during dyeing, and high quality yarn can be obtained. In addition, the coating does not break, so it slides well with the spinning dope and the yarn separation is improved.

Next, in order to clarify the effects of the method for manufacturing a spinneret according to the present invention, specific examples and conventional examples thereof will be described.

(Example) As shown in Fig. 5a, a spinneret material 1 made of Ta with a thickness of 0.4 mm and a diameter of 80 mm has a diameter of 0.4 mm and a depth of 0.35 mm.
After drilling 15,000 stock solution introduction holes 2 of
A _5- layer TaO film 6 is formed, and then, as shown in FIG. 5b, a 50 μm diameter stock solution discharge hole 4 is bored at the bottom of each stock solution introduction hole 2 by plastic working with a punch tool 3, and the protrusion 1a is polished. When the spinneret was removed and a spinneret was made, the wall surface of the raw solution discharge hole 4 of the spinneret was all protected by the coating 6' and was a smooth wall surface that followed the shape of the punch tool 3.

(Conventional example) As shown in Figure 1, it is made of Ta and has a thickness of 0.5 mm and a diameter.
After drilling 20,000 stock solution introduction holes 2 with a diameter of 0.5mm and a depth of 0.45mm in a 120mm spinneret material 1, 0.50% of a lubricating oil 5, for example, rapeseed oil, is applied to the bottom of the stock solution introduction holes 2 as shown in Fig. 3. mm was coated and a spinneret was made by drilling a dope discharge hole 4 with a diameter of 50 μm at the bottom of each dope inlet hole 2 by plastic working with a punch tool 3. Ta melted and adhered to the punch tool 3, forming a spinneret. In many cases, the walls of the stock solution discharge holes 4 were scratched, forming multi-acicular holes 4' as shown in FIG.

However, when wet spinning was performed using the spinnerets of these examples and the conventional example, the yarn spun with the spinneret of the example had no flaws and no color unevenness occurred during dyeing, whereas the yarn spun using the conventional example The yarn spun with the spinneret had vertical flaws, which caused uneven coloring during dyeing.

As can be seen from the above explanation, according to the manufacturing method of the spinneret of the present invention, the spinneret has a large number of fine spinning holes.
A wet spinneret made of Ta material can be made without damaging the wall surface of the raw solution discharge hole of the spinning hole.
Therefore, there is an excellent effect that it is possible to obtain a spinneret that can spin yarn of good quality without damaging the surface of the spun yarn and causing no color unevenness during dyeing.

[Brief explanation of drawings]

Fig. 1 is a vertical cross-sectional view of a main part showing a conventional method for manufacturing a spinneret, Fig. 2 is a cross-sectional view showing the shape of a stock solution discharge hole in a spinneret obtained by the manufacturing method, and Fig. FIG. 4 is a cross-sectional view of main parts showing another conventional method for manufacturing a spinneret, FIG. FIG. 2 is a longitudinal sectional view of a main part showing steps of a method for manufacturing a spinneret according to the present invention. 1... Spinneret material, 2... Stock solution introduction hole, 3...
Punch tool, 4... undiluted solution discharge hole, 6... coating of the undiluted solution introduction hole, 6'... coating of the undiluted solution discharge hole.

Claims (1)

[Claims] 1. In a method for manufacturing a spinneret made of Ta material having a large number of fine spinning holes consisting of a stock solution introduction hole and a continuous solution discharge hole, after drilling the stock solution introduction hole, chemical or physical means are used. 1. A method for producing a spinneret, comprising: forming a Ta oxide film on the wall surface of a dope introduction hole, and then punching a dope discharge hole by plastic working with a punch tool.