JP3463145B2 - Melt spinning method of polyphenylene sulfide monofilament - Google Patents

Description

Description: BACKGROUND OF THE INVENTION The present invention relates to polyphenylenesulfur
Relates melt spinning method id monofilament, more particularly, it is possible sufficiently suppressed mouthpiece dirt, high quality linear径斑superior in reduced uniformity polyphenylene
The present invention relates to a melt spinning method capable of obtaining nylene sulfide monofilament. 2. Description of the Related Art Conventionally, in a melt-spinning method which comprises extruding a thermoplastic resin from a die into the air and immediately leading a spun yarn to a cooling medium bath for cooling, a fiber form such as multifilament or monofilament is used. Regardless of the above, sublimable foreign matter accumulates around the nozzle of the mouthpiece over time, and this foreign matter becomes a stain on the mouthpiece, causing a problem such as unevenness of wire diameter and deterioration of spinning process. Therefore,
In the conventional melt spinning method, it is necessary to maintain a good spinning process condition by periodically cleaning the die or changing the die, which leads to a rise in costs, labor costs and material losses. Had to be forced. By the way, as a means for suppressing the accumulation of sublimable foreign matter around the nozzle of the base, for example, a method of sucking the sublimable foreign matter directly below the base, a method of steam sealing just below the base, and the like have been conventionally considered. But especially polyfe
In the melt spinning method of nylene sulfide monofilament, since there is always a space (air layer) between the die surface and the cooling medium bath, there is a limit in sufficiently suppressing the accumulation of foreign matter by the above method. In addition, the resulting polyphenylene is adversely affected by suction and steam disturbances.
There remains a problem that sulfide monofilaments tend to have uneven diameters. Therefore, in the above-mentioned conventional method, it is difficult to achieve both a sufficient suppression of stains on the base and an improvement in the unevenness of the wire diameter, and the improvement has been strongly desired. DISCLOSURE OF THE INVENTION The present invention has been made in order to solve the problems in the above-mentioned conventional method for melt-spinning polyphenylene sulfide monofilament.
Has been achieved. Therefore, the object of the present invention is to
It is an object of the present invention to provide a melt-spinning method capable of sufficiently suppressing spinneret stain and obtaining a high-quality polyphenylene sulfide monofilament having a small unevenness in wire diameter and excellent uniformity. To achieve the above object SUMMARY OF THE INVENTION The polyphenylene sulfide Monofira <br/> melt spinning method of placement of the present invention, melt-extruded polyphenylene sulfide <br/> from a nozzle into the air, When the spun yarn is immediately introduced into the cooling medium bath and cooled, a tubular body is arranged in the spun yarn passage from directly below the base surface to the cooling medium bath such that at least the lower surface is immersed in the cooling medium. It is characterized in that an inert gas is passed through the cylindrical body. Polyphenylene sulfur applied to the melt spinning method of the present invention
Id, For example other matting agents, colorants, stabilizers, flame retardants, antistatic agents, light stabilizer, weathering agent, may contain a predetermined amount of additives such as a plasticizer. In performing melt spinning method of polyphenylene sulfide <br/> monofilament of the present invention, port
The phenylene sulfide is melt-extruded from a die into the air, and the spun yarn is immediately introduced into a cooling medium bath for cooling. As the cooling medium used in the present invention, water is generally used, but an organic solvent other than water, such as polyethylene glycol, trichloroethylene, and glycerin, can also be used. Then, in the method of the present invention, a tubular body is disposed in the spun yarn passage from just below the base surface to the above-mentioned cooling medium bath so that at least the lower surface is immersed in the cooling medium. It is characterized in that an inert gas is allowed to flow therethrough. First, an example of a melt spinning apparatus used in the present invention will be described with reference to FIG. FIG.
1 is a schematic view showing an example of a melt spinning apparatus used in the method of the present invention, wherein 1 is an extruder spinning machine, 2 is a spinning pack, 3 is a spinneret, 7 is a spun yarn, 8 is a cooling medium bath, 9 Indicates a cooling medium. Here, a cylindrical body 4 is disposed in the spun yarn passage from directly below the base 3 to the cooling medium bath 8, and at least the lower surface 4 a of the cylindrical body 4 is accommodated in the cooling medium bath 8. It is in a state of being immersed in the cooled cooling medium 9. The shape of the cylindrical body 4 is not particularly limited, and a circular, square, or elliptical cross-section can be used, but the upper surface 4b of the cylindrical body 4 is in contact with the lower surface of the spinning pack 2. And the lower surface 4a has a vertical height of at least 5 to 15 mm.
It is an essential requirement that the degree is immersed in the cooling medium 9. In addition, the inert gas 6 is always circulated through the inert gas inlet hole 5 provided in a part of the side surface of the cylindrical body 4. The gas 6 is supplied from the gap between the upper surface 4b of the cylindrical body 4 and the spinning pack 2 and / or a discharge hole (not shown) provided at an appropriate position of the cylindrical body 4 as necessary. 4 to the outside. Here, when the tubular body 4 is a completely closed system, the inside of the tubular body 4 is over-pressurized by the inert gas which is always flowed in, and this has an adverse effect on the yarn such as unevenness in the wire diameter, which is not preferable. . Examples of the inert gas 6 used in the present invention include various gases such as nitrogen, helium, argon, and neon. Among them, nitrogen gas is preferably used because it is inexpensive. Cylindrical body 4
The inflow amount of the inert gas 6 into the cylinder 4 is set according to the size of the cylindrical body 4. As a guide of the appropriate inflow amount, the inflow amount (N
l) / the volume of the cylindrical body (cm ³ ) is 6 × 10 −4 to 1 ×
10 ⁻³ , usually 1 with a nitrogen gas flow meter.
６6 Nl / min, particularly preferably about 2 to 3 Nl / min. If the gas flow rate is too low, the effect of suppressing foreign matter accumulation is not sufficiently exhibited, and if the gas flow rate is too high, not only does the spun yarn disturb, but it also cools the spinneret surface and adversely affects the quality of the monofilament. Is not preferred. Thus, by adopting the above configuration,
All the spun yarn passages from directly below the base 3 to the cooling medium 9 in the cooling medium bath 8 are kept under an inert gas atmosphere, and the inside of the cylindrical body 4 does not cause disturbance of the spun yarn 7. In addition, it is important that the inert gas 6 is filled to such an extent that air is not mixed. Next, using the device shown in FIG.
A specific example of actually performing melt spinning of a polyphenylene sulfide resin and the operation in that case will be described. Polyphenylene melted by extruder spinning machine 1
The sulfide resin is metered by a gear pump (not shown) and enters the spin pack 2. The spun yarn 7 melt-extruded from the spinneret 3 incorporated in the spinning pack 2 passes through the inert gas atmosphere 6 in the tubular body 4 and is immediately led into the cooling medium 9 of the cooling medium bath 8. Cool down. In this case, the lower surface 4a of the cylindrical body 4 is immersed in the cooling medium 9 and the spun yarn 7 is immersed in the cylindrical body 4 by appropriately controlling the inflow amount of the inert gas 6. In addition to the fact that the inside of the cylindrical body 4 is subjected to the conduction heating from the spinning machine 1 to be subjected to the slow cooling condition, the spun yarn 7 does not suffer from unevenness in the wire diameter. , And is stably guided into the cooling medium 9. In addition, the inert gas 6 circulated in the cylindrical body 4 keeps the surface of the base 3 under the atmosphere of the inert gas 6 at all times, thereby suppressing the generation of sublimable foreign matter and preventing the foreign matter from being gelled by the foreign matter. Because you can
Dirt around the nozzle of the base 3 is reduced, the base cleaning or replacement cycle can be drastically extended, and the productivity can be improved. The configuration and effects of the present invention will be further described with reference to examples. In addition, the evaluation of the wire diameter spots and the effect of suppressing the base stain in the following Examples and Comparative Examples was performed by the following method. [Wire diameter unevenness] ... Using a laser wire diameter machine (M501A manufactured by Anritsu Denki), the obtained monofilament was used to obtain a yarn speed of 50 m.
/ Min, and at the same time, plot the fluctuation range on a chart, read the difference (maximum-minimum) of the fluctuation range on the chart,
= 5. However, figures are rounded off,
The unit is indicated by μ. [Stain Suppression Effect] Sublimable foreign substances are deposited around the mouth of the nozzle, and the generation of the foreign matter deteriorates the spinning process. The maximum time required to clean the surface of the mouth is determined. Example 1 Polyphenylene sulfide having a melt flow rate of 70 measured by the method of ASTEM D1238-32 (manufactured by Toray Phillips) was melted at 290 ° C. by an extruder spinning machine having a diameter of 40 mm, and was melt-extruded from a die. Was immediately led into a cold hot water bath at 80 ° C. At this time, a square cylindrical body (vertical: 20 cm, side: 22 cm, height: 8 cm) was placed from just below the base surface into the cooling hot water so that the lower surface was immersed in the cooling hot water by about 10 mm. In addition, the cylindrical body was provided with one hole having a diameter of 3 mm on the side surface 20 mm above the lower surface in order to prevent pressurization due to the flowing gas. Then, nitrogen gas at room temperature was always flowed into the cylindrical body at a flow rate of 3 Nl / min with a N ₂ flow meter. In addition, the discharge rate per one hole of the die was 26.5 g / min. The spun yarn after cooling was 5.0 in accordance with a normal drawing method.
It was drawn twice to obtain a polyphenylene sulfide monofilament having a diameter of 0.50 mm. The monofilament had a small unevenness in the diameter of 22 μm, and the effect of suppressing the base stain was 73 μm.
Time was excellent. Comparative Example 1 A 0.50 mm diameter was obtained in the same manner as in Example 1 except that the arrangement of the cylindrical body and the inflow of nitrogen gas into the cylindrical body were omitted.
Of polyphenylene sulfide monofilament was obtained. The variation in the diameter of this monofilament is as large as 42 μ,
The effect of suppressing the base stain was 39 hours, which was inferior to Example 1 . [Effect of the Invention] As described above in detail, port of the present invention
According to the melt spinning method of phenylene sulfide monofilament, high-quality polyphenylene that can sufficiently suppress die contamination and has small uniformity in wire diameter and excellent uniformity.
It is possible to obtain sulfide monofilaments.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic view showing one example of a melt spinning apparatus used in the method of the present invention. [Description of Signs] 1 Extruder spinning machine 2 Spinning pack 3 Spinneret 4 Cylindrical body 4a 下面 Lower surface 4b 上面 Upper surface 5 Inert gas inlet 6 Inert gas atmosphere 7 Spun yarn 8 Cooling medium bath 9 Cooling medium

Continuation of the front page (72) Inventor Akira Fureki 1 Kawara, Showa-cho, Okazaki City, Aichi Prefecture Toray Monofilament Co., Ltd. (56) References JP-A-3-40812 (JP, A) JP-A-48-61717 (JP, A) JP-B-47-47528 (JP, B1) U.S. Pat. No. 2,323,383 (US, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) D01D 5/088

Claims (1)

(57) [Claims] [Claim 1] Polyphenylene sulfide is melt-extruded from a die into the air, and the spun yarn is immediately introduced into a cooling medium bath for cooling. of the spun yarn passage, polyphenylene at least the lower surface is arranged a cylindrical body that is immersed in the cooling medium, characterized in that allowed to flow through the inert gas into the cylindrical body during
A melt spinning method for a sulfide monofilament.