JPH10298821A - Spinneret for melt-spinning and melt-spinning method using the spinneret - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a spinneret for melt-spinning capable of sealing the circumference of the extrusion nozzles on the spinneret face uniformly for each nozzle spending a small amount of inert gas. SOLUTION: This spinneret apparatus has a spinneret plate 2 placed on a spinneret holder 1. A number of polymer extrusion nozzles 9 are opened on the spinneret plate 2 in circular form and an equalizing chamber 6 is placed along the outer circumference of the polymer extrusion nozzles 9 opened in the form of a ring. Plural small pipes 7 each forming a gas-blasting hole 8 are arranged in a manner connecting an end of the pipe to the equalizing chamber 6 and opening the other end near the polymer extrusion nozzle 9. The spinneret holder 1 contains a gas-introducing part 4 to introduce a gas through a gas-introducing pipe 3 and a gas flowing channel 4 to introduce, the gas from the gas-introducing part 4 to the equalizing chamber 6 at the outer circumference of the spinneret plate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a melt spinning die apparatus and a melt spinning method capable of preventing the adhesion of dirt by sealing the periphery of a polymer discharge hole of a spinning die plate with an inert gas. It is.

[0002]

2. Description of the Related Art When melt spinning of a thermoplastic polymer such as polyamide or polyester is continuously performed for a long time, a polymer or a low molecular weight substance generated from the polymer adheres to the periphery of a polymer discharge hole of a spinneret. When such deposits react with oxygen in the air, they are denatured or hardened, whereby the polymer is not uniformly discharged from the discharge holes, and the resulting yarns are spotted or broken, resulting in operation. There is a problem that the property is deteriorated.

[0003] In order to prevent such a problem from occurring, the material of the base surface is made to be difficult for deposits to adhere thereto, a release agent is applied to the base surface to prevent adhesion, and an antioxidant is applied to the base surface. Are applied to prevent oxidation of the deposits, and a method of sealing the periphery of the base with a gas inert to the polymer to prevent oxidation of the deposits.

Among them, Japanese Patent Publication No. 53-45416 discloses an example of a spinneret device which jets steam at a certain angle with respect to the yarn flow, as an example of sealing the periphery of the nozzle surface with an inert gas. Japanese Patent Publication No. 53-9291 discloses a spinneret device for supplying water vapor to the periphery of a spinneret by impinging water vapor on a cylindrical buffer wall. Further, Japanese Patent Publication No. 50-21564 discloses an apparatus for supplying an inert gas in a horizontal direction with respect to the base surface from the entire periphery of the inner surface of the base pack immediately below the base surface.

However, these devices cannot efficiently seal only the periphery of the discharge hole on the base surface, and it is necessary to use a large amount of inert gas in order to improve the sealing effect. However, when the usage amount of the inert gas is increased, there is a problem in that the airflow is disturbed and the yarn sways, resulting in a yarn with a spotted yarn or a broken yarn. Further, there is a problem that the cost of the inert gas increases.

On the other hand, JP-A-51-58511 discloses that each discharge hole is provided at the apex of a conical protrusion protruding from a base plate, and an inert gas is efficiently blown only to the periphery of each discharge hole. There has been proposed a spinneret device adapted to be used.
In other words, this cap device overlaps a cap plate with a conical hole covering the periphery of each discharge hole at the apex of the conical protrusion on the cap plate, and allows the inert gas to flow through the gap between these two plates. Thus, the inert gas is supplied only to the peripheral portion of each polymer discharge term.

According to this device, it is possible to seal the periphery of the polymer discharge hole with the inert gas even if the amount of the inert gas used is relatively small. However, there is no contrivance for supplying a uniform amount of inert gas to each discharge hole, and there is a variation in the supply amount of inert gas, resulting in a difference in sealing effect for each discharge hole. was there. Further, since the polymer discharge hole is provided at the apex of the conical protrusion, there is a problem that the discharge hole is easily damaged or deformed in a process of assembling or cleaning the base device.

[0008]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems and efficiently seals around the discharge holes on the base surface with a small amount of inert gas and uniformly seals the respective discharge holes. It is an object of the present invention to provide a melt spinning die apparatus and a melt spinning method that can perform the spinning.

[0009]

Means for Solving the Problems The present inventors have made intensive studies to solve the above-mentioned problems, and as a result, have reached the present invention.
That is, the present invention has the following configurations (1) and (2). (1) A base device in which a base plate is provided in a base holder, wherein the base plate has a polymer discharge hole formed in an annular shape on a surface thereof, and a pressure equalizing is performed along an annular outer periphery in which the polymer discharge hole is formed. A chamber is provided, and one end is connected to the pressure equalizing chamber, and the other end is opened near the polymer discharge hole, and a plurality of thin tubes serving as gas ejection holes are provided. 1. A melt spinning device, comprising: a gas introduction portion for introducing gas from a gas inlet; and a gas flow passage for guiding the gas from the gas introduction portion to a pressure equalizing chamber on an outer periphery of a base plate. (2) The melt spinning using the melt spinning device according to the configuration (1), wherein an inert gas is blown from a gas ejection hole and melt spinning is performed while sealing around the polymer discharge hole with the inert gas. Method.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings. FIG. 1 is a partially omitted cross-sectional explanatory view showing an embodiment of the melt spinning die device of the present invention, and FIG. 2 is a view of a discharge hole surface of a die plate (12 discharge holes) of the die device of FIG. FIG. The spinneret for melt spinning of the present invention is a spinneret in which the spinneret plate 2 is installed on the spinneret holder 1. A pressure equalizing chamber 6 is provided along an outer periphery of an annular hole in which is bored. Further, the base plate 2 is provided with a plurality of thin tubes 7 having one end connected to the pressure equalizing chamber 6 and the other end opened in the vicinity of the polymer discharge hole 9 and serving as a gas ejection hole 8.
In the base holder 1, there are provided a gas introduction part 4 connected to the gas introduction pipe 3 and introducing a gas, and a gas flow path 5 guiding the gas from the gas introduction part 4 to a pressure equalizing chamber 6 on the outer periphery of the base plate 2. Have been.

The gas introduction pipe 3 has one end connected to a supply source of an inert gas and the other end provided at an arbitrary position of the base holder 1 (in FIG. 1, a lower surface of the base holder).
The inert gas is supplied into the base holder 1 through the gas introduction pipe 3. Subsequently, the inert gas passes through the gas flow path 5 from the gas introduction unit 4 and then enters the pressure equalizing chamber 6 provided as an annular space on the outer periphery of the die plate 2 along the outer periphery of the polymer discharge hole 9. Then, the inert gas is guided to a plurality of small tubes 7 connected to the pressure equalizing chamber 6 and is ejected from gas ejection holes 8 opened near the polymer ejection holes 9 at the other end.

As a result, the periphery of the polymer discharge hole 9 can be sealed, and the periphery of the polymer discharge hole 9 can be prevented from contacting oxygen in the air. Further, the inert gas is introduced into the base holder 1 from the gas introduction pipe 3 and is heated to the same temperature as the base holder 1 while passing through the gas flow path 5 from the gas introduction part 4. Since the gas is ejected from the gas ejection holes 8 through the pressure chamber 6, the temperature of the atmosphere below the mouthpiece plate 2 is not lowered by the ejection of the inert gas, and the occurrence of thread spots does not occur.

Next, each part of the die device of the present invention will be described. First, the pressure equalizing chamber 6 is a space for introducing an inert gas led from the gas flow path 5 of the base holder 1 to the entire outer peripheral portion of the base plate 2. This space is once filled with the inert gas. , The pressure becomes substantially uniform. As long as the pressure equalizing chamber 6 can introduce an inert gas from the gas flow path 5 of the base holder 1, the pressure equalizing chamber 6 is higher than the position shown in FIG.
May be an annular space included at a position close to the center of the device.

The gas outlet 8, which is the opening at the other end of the thin tube 7, is provided near the polymer outlet 9. The gas ejection holes 8 are preferably provided with one gas ejection hole 8 for one polymer ejection hole 9. However, as long as the periphery of the polymer ejection hole 9 can be sealed, a plurality of polymer ejection holes 9 are provided. Alternatively, one gas ejection hole 8 may be provided.

The polymer discharge holes 9 are perforated in an annular shape on the base surface, but are not limited to a single circle. As described above, the plurality of polymer discharge holes 9 are formed into one gas discharge hole. As long as the periphery of these polymer discharge holes 9 can be sealed in 8, the holes may be perforated in multiple circles.

Therefore, the gas ejection holes 8 and the polymer ejection holes 9
The preferred range of the ratio of the numbers is 1: 3 to 4: 1. If the ratio of the gas ejection holes 8 is less than 1: 3, it becomes difficult to completely seal the periphery of the polymer ejection holes 9, while if the ratio of the gas ejection holes 8 is more than 4: 1, the sealing is not performed. Does not change much, and the cost of machining the thin tube 7 and the gas ejection hole 8 in the base plate 2 increases, which is not preferable.

The gas ejection holes 8 are located in the vicinity of the polymer ejection holes 9. More specifically, as shown in FIG. 9 may be provided between the polymer discharge holes 9 on the same circumference as the perforated circumference. The distance between them is 1 to 10 mm
It is preferable to set the degree. This distance is the shortest distance connecting the points on the outer periphery of the gas ejection holes 8 and the polymer ejection holes 9. If the distance is less than 1 mm, the spouted inert gas may affect the formation of the yarn and cause yarn spots. If the distance exceeds 10 mm, the area around the polymer discharge hole 9 is completely sealed with the inert gas. Can be difficult to do.

The shape of the gas ejection hole 8 is not particularly limited, and may be a circle, an ellipse, a slit, or the like. The size is not particularly limited. For example, when the shape is circular, the diameter is preferably about 0.1 to 10 mm. Further, the material of the die device of the present invention is not particularly limited, and stainless steel or the like is used as in a general die device.

In the melt spinning method of the present invention,
Using the melt spinning device as described above, the gas ejection holes 8
Then, an inert gas is blown around the polymer discharge hole 9 and melt spinning is performed while sealing around the polymer discharge hole 9 with the inert gas. The thermoplastic polymer to which the method of the present invention can be applied is not particularly limited, and melt spinning such as polyamides such as nylon 6, nylon 66, and nylon 46, and polyesters such as polyethylene terephthalate and polylactic acid is preferably used. It can be carried out.

The inert gas used in the present invention is a gas having a low reactivity with a polymer to be spun or a low molecular weight substance adhering to the surface of a die. For example, steam or nitrogen is used. In addition, the amount of the inert gas ejected is appropriately changed depending on the distance to the polymer ejection hole, the type of gas used, and the like within a range that can completely seal the periphery of the polymer ejection hole and does not affect the formation of the yarn. However, it is preferable that the ejection amount per one polymer discharge hole be approximately 0.1 to 10 liter / hour.

[0021]

Next, the present invention will be described specifically with reference to examples. The evaluation of the degree of dirt adhesion in the examples was performed as follows. [Degree of dirt adhesion] Melt spinning was continuously performed using a single-spindle spinning device. No yarn breakage occurred, and if no surface sweep was necessary, the yarn breakage occurred frequently after 168 hours. When the necessity of cleaning occurred, the degree of adhesion of dirt on the discharge hole surface of the die plate at that time was visually evaluated as follows. ：: There is no adhesion of dirt. Δ: A small amount of dirt adhered and accumulated. ×: Many stains adhere and deposit.

Embodiment 1 A base device as shown in FIG.
m), 36 polymer ejection holes (diameter 0.25 mm) are perforated in a single circle, and 2 mm from each polymer ejection hole.
The one provided with gas ejection holes (36 in total) on the outer peripheral side was used. Then, the relative viscosity (concentration of 1 g /
dl, measured at a temperature of 25 ° C.) and melt-spun at 265 ° C. using a 2.56 nylon 6 chip containing 0.1% by weight of magnesium stearate as an additive. continue,
The cooled and solidified yarn was taken up by a take-up roller at a speed of 4310 m / min, and then wound by a winder at a take-up speed of 4300 m / min to obtain a 110 d / 36f yarn. At this time, spinning was performed while continuously feeding nitrogen into the die holder at a flow rate of 36 liters / hour from the gas inlet tube and jetting nitrogen at a flow rate of 1 liter / hour per gas ejection hole. Table 1 shows the continuous operation time and the evaluation of the degree of contamination of the base plate at this time.

Example 2 Except that steam was used instead of nitrogen as the inert gas,
Spinning was performed in the same manner as in Example 1. Table 1 shows the continuous operation time and the evaluation of the degree of contamination of the base plate at this time.

Comparative Example 1 The same procedure as in Example 1 was carried out except that a pressure equalizing chamber, a thin tube, and a base plate having no gas ejection holes were used. Table 1 shows the continuous operation time and the evaluation of the degree of contamination of the base plate at this time.

COMPARATIVE EXAMPLE 2 A steam sealing device was installed independently of the spinneret device.
The operation was performed in the same manner as in Comparative Example 1, except that steam at a flow rate of 00 liter / hour was ejected to seal around the polymer discharge hole. Table 1 shows the continuous operation time and the evaluation of the degree of contamination of the base plate at this time.

EXAMPLE 3 Twenty-four polymer discharge holes (diameter: 0.25 mm) are formed in a single circular shape in a die plate (surface diameter: 90 mm), and are located 2 mm away from each polymer discharge hole. The same procedure as in Example 1 was carried out except that a 70d / 24f yarn was obtained using a gas discharge hole (24 in total) provided on the same circumference as the polymer discharge hole. At this time, nitrogen was continuously fed into the cap holder at a flow rate of 15 liters / hour from the gas introduction pipe,
The spinning was performed while ejecting nitrogen at a flow rate of 0.63 liter / hour per gas ejection hole. Table 1 shows the continuous operation time and the evaluation of the degree of contamination of the base plate at this time.

Comparative Example 3 The same procedure as in Example 3 was carried out except that a die plate having no pressure equalizing chamber, a thin tube, and a gas ejection hole was used. Table 1 shows the continuous operation time and the evaluation of the degree of contamination of the base plate at this time.

[0028]

[Table 1]

As is clear from Table 1, according to the melt spinning method using the spinnerets of Examples 1 to 3, there is no adhesion of the polymer near the polymer discharge holes of the die plate even after continuous operation for 168 hours. , And high-quality yarn without thread spots could be continuously obtained. On the other hand, in Comparative Examples 1 and 3, since there was no gas ejection hole or the like in the base plate and an inert gas could not be blown near the polymer ejection holes, Comparative Example 1 was operated for 24 hours, and Comparative Example 3 was operated for 48 hours. Later, thread breaks occurred frequently, necessitating surface cleaning. At this time, a large amount of dirt was attached and deposited on the discharge hole surface of the base plate. In Comparative Example 2,
The use of a steam-sealing device, which seals the entire base plate by ejecting steam from the two ejection holes, did not sufficiently prevent the adhesion of dirt. Thread breakage occurred after 72 hours of operation, necessitating surface cleaning. . At this time, on the discharge hole surface of the base plate,
A small amount of dirt was deposited and deposited. Also during operation hours,
Yarn swaying under the base plate was large.

[0030]

According to the spinneret of the present invention, a small amount of inert gas is used and the area around the discharge hole on the surface of the spinneret is efficiently used.
In addition, since each discharge hole can be uniformly sealed,
It is possible to continuously obtain a high-quality yarn having no spots without sweeping for a long time.

[Brief description of the drawings]

FIG. 1 is a partially omitted cross-sectional explanatory view showing one embodiment of a melt spinning die device according to the present invention.

FIG. 2 is an explanatory view of a discharge hole surface of a base plate of the base device of FIG. 1;

[Description of Signs] 1 Cap holder 2 Cap plate 3 Gas introduction pipe 4 Gas introduction section 5 Gas flow path 6 Equalizing chamber 7 Narrow tube 8 Gas ejection hole 9 Polymer discharge hole

Claims (2)

[Claims] 1. A base device in which a base plate is provided in a base holder, wherein the base plate has a polymer discharge hole formed in a ring shape on a surface thereof, and the polymer discharge hole extends along an annular outer periphery. A pressure equalizing chamber is provided, and one end is connected to the pressure equalizing chamber, the other end is opened near the polymer discharge hole, and a plurality of thin tubes serving as gas ejection holes are provided. A spinneret for melt spinning, comprising: a gas inlet for introducing a gas from an inlet pipe; and a gas flow path for guiding the gas from the gas inlet to a pressure equalizing chamber on the outer periphery of a base plate. 2. A method according to claim 1, wherein the melt spinning is performed by blowing an inert gas from a gas ejection hole and sealing around the polymer discharge hole with the inert gas. Spinning method.