JP5946565B1 - Spinneret and ultrafine fiber manufacturing equipment - Google Patents

Abstract

[PROBLEMS] To stably spin a polymer solution into fine fibers even with a small amount of hot air gas without using a high voltage, and can be easily reduced in size and weight, thereby suppressing production costs. A spinneret and an ultrafine fiber manufacturing apparatus are provided. SOLUTION: One or more solution nozzles 22 capable of discharging a polymer solution obtained by dissolving a raw material polymer in a solvent inside a spinneret 20, and hot air is blown into the polymer solution discharged from the solution nozzle 22 to draw into a fiber. One or more hot air nozzles 24 are formed. The hot air nozzle 22 and the solution nozzle 24 are arranged close to each other so that the blowing direction of the hot air nozzle 24 and the discharge direction of the solution nozzle 22 intersect below the base lower surface 20a. [Selection] Figure 1

Description

The present invention relates to a spinneret and an ultrafine fiber manufacturing apparatus including the spinneret.

In general, nanofibers defined as fine fibers having a diameter of 1 μm or less have been developed, and an ESD (Electro Spray Deposition) method is known as a method for producing such ultrafine fibers.
This ESD method is a method for producing fibers by applying a high voltage to a polymer solution obtained by dissolving a raw material polymer in a solvent. That is, the polymer solution is discharged from the nozzle, and the solvent in the discharged polymer solution is instantly evaporated and stretched by Coulomb force under the condition where a DC high voltage is applied between the nozzle and the collecting portion. Then, ultrafine fibers such as nanofibers are deposited on the surface of the collection part (for example, Patent Document 1).

As described above, since the ESD method generally handles a high voltage, it is necessary to have a structure that prevents ignition by a solvent and the handling is troublesome.

Further, Patent Document 2 discloses a nano-fiber which is spun from a spinning nozzle without using such a high voltage and is provided with a ring-shaped high-speed air outlet coaxially with the central outlet so as to surround the central outlet of the spinning nozzle. A fiber manufacturing method is described.

JP 2012-127008 A JP 2013-185273 A

As described above, in the configuration shown in Patent Document 1, handling is troublesome in order to prevent ignition and the like.
On the other hand, in the configuration shown in Patent Document 2, the problem as shown in Patent Document 1 is solved by not using a high voltage. However, there is a high-speed air outlet that coaxially extends the polymer fiber around the central outlet that discharges the polymer solution, and the high-speed air outlet has a large diameter and requires a large amount of hot air gas for extension. In addition, there is a problem that the structure of the entire spinning nozzle including the high-speed air outlet is enlarged and complicated.

Therefore, the present invention has been made in view of the above problems, and does not use a high voltage, and the discharged polymer solution can be stably made into ultrafine fibers such as nanofibers even with a small amount of hot air gas. An object of the present invention is to provide a spinneret and an ultra-fine fiber manufacturing apparatus that can be spun and that can be easily reduced in size and weight and can suppress manufacturing costs.

In order to achieve the above object, the invention described in claim 1 is characterized in that one or more solution nozzles capable of discharging a polymer solution in which a raw material polymer is dissolved in a solvent, and hot air is blown into the polymer solution discharged from the solution nozzle. A spinneret comprising one or more hot air nozzles that are stretched into a fiber shape,
Solution nozzle and hot air nozzles, Ri columnar hollow body der each having a constant cross-sectional shape, close to each other,
The central axis of the solution nozzle and the central axis of the hot air nozzle exist on the same plane, and the extension line of the central axis of the solution nozzle and the extension line of the central axis of the hot air nozzle intersect at the lower side of the lower surface of the base It is a spinneret characterized by being made. If comprised in this way, even if it is the quantity of a small hot air gas, the discharged polymer solution can be stably spun into an ultrafine fiber like a nanofiber. Further, a space for arranging the solution nozzle and the hot air nozzle in the spinneret is small, and the degree of freedom of arrangement increases.

According to the present invention, a polymer solution obtained by dissolving a raw material polymer in a solvent can be stably spun into ultrafine fibers such as nanofibers with a small amount of hot air gas, so that the amount of hot air gas used can be reduced. Further, a space required for providing the discharge nozzle and the blowout nozzle is small, and a large number of such nozzles can be arranged in the spinneret. For this reason, the spinneret can be reduced in size and weight, and the manufacturing cost can be reduced.

It is sectional drawing of the spinneret by the 1st Embodiment of this invention, and a block of an ultrafine fiber manufacturing apparatus provided with the same. It is a top view of the spinneret shown in FIG. It is sectional drawing of the spinneret by the 2nd Embodiment of this invention. It is sectional drawing of the spinneret by the 3rd Embodiment of this invention. It is a top view of the spinneret shown in FIG. It is a top view of the spinneret by the 4th Embodiment of this invention. It is a top view of the spinneret by the 5th Embodiment of this invention. It is sectional drawing of the spinneret along the AA line of FIG. It is a top view of the spinneret according to the sixth embodiment of the present invention. It is a perspective view of the ultrafine fiber manufacturing apparatus provided with the spinneret of FIG. FIG. 10 is a perspective view of an ultrafine fiber manufacturing apparatus provided with the spinneret of FIG. 9.

Hereinafter, the spinneret 20 and the ultrafine fiber manufacturing apparatus of the first embodiment will be described with reference to FIGS. 1 and 2.
As shown in FIG. 1, the microfiber manufacturing apparatus includes a polymer solution supply apparatus 200 for supplying a polymer solution, a hot air generation apparatus 300 for generating hot air, and a polymer solution extruded from the polymer solution supply apparatus 200 as fibers. And a spinneret 20 for discharging and spinning.

As shown in FIGS. 1 and 2, a solution nozzle 22 that discharges a polymer solution and a hot air nozzle 24 that blows hot air gas are formed inside the spinneret 20.
Here, each of the solution nozzle 22 and the hot air nozzle 24 is a columnar hollow body having a constant cross section, and is arranged close to each other. Furthermore, the central axis O _g of the center axis O _r and hot air nozzles 24 of the solution nozzle 22 is present on the same plane, the central axis O _r is inclined at the spinneret 20, the central axis O _r extension and the center axis of the The extension line of O _g intersects at an angle θ ₁ at a point X on the lower side of the base lower surface 20a.
Thereby, even if the amount of hot air gas blown out from the hot air nozzle 24 is small, the polymer solution discharged from the solution nozzle 22 is stretched while being instantly solidified by the hot air gas blown out from the hot air nozzle 24. Such an ultrafine fiber is obtained.

The solution nozzle 22 is not particularly limited as long as it can discharge the polymer solution, and the shape of the cross section is not particularly limited. A circular shape is preferred from the standpoint of uniform processing.

In addition, the size of the cross section of the solution nozzle 22 is appropriately selected depending on the type and concentration of the raw material polymer and solvent, but in the case of a circular shape, the diameter is preferably 0.1 mm to 1.0 mm, and 0.2 mm to 0.5 mm. Is more preferable.

The hot air nozzle 24 only needs to be capable of blowing hot air gas, and the shape of the cross section is not particularly limited. The shape may be different.

In addition, the size of the cross section of the hot air nozzle 24 is appropriately selected depending on the type and concentration of the raw material polymer and the solvent. In the case of a circular shape, the diameter is preferably 0.2 mm to 3.0 mm, and 0.5 mm to 1.5 mm. Is more preferable.

The solution nozzle 22 and the hot air nozzle 24 are arranged close to each other, and the shortest distance t _{1 at} the base lower surface 20a is preferably 0.1 mm to 5 mm, more preferably 1 mm to 4.5 mm, and more preferably 2 mm to 4 mm. Further preferred. If it is less than 0.1 mm, it is too close to be processed, and if it exceeds 5 mm, stretching of the polymer solution with hot air gas is insufficient and it becomes difficult to obtain fine fibers.

In Figure 1, the angle theta ₁ formed by the extension line of the extended line and the center axis O _g of the center axis O _r is preferably 30 degrees from 0 degrees, more preferably 25 degrees 0 degrees, 20 degrees 5 degrees more preferable. If it exceeds 30 degrees, stretching of the polymer fiber by hot air gas is insufficient, and it becomes difficult to obtain ultrafine fibers such as nanofibers made of fine fibers. Incidentally, with the angle theta ₁ approaches 0 °, the distance increases between X and the base lower surface 20a that is shown in FIG. 1, nanofibers stretching polymer fibers by hot gas even in this case consists of fine fibers made such Can be obtained.

In FIG. 1, the solution nozzle 22 is inclined in the spinneret 20. Instead, the hot air nozzle 24 may be inclined, or both may be inclined. However, even in these cases, the angle theta ₁ formed by the extension line of the extended line and the center axis O _g of the center axis O _r is preferably within 30 degrees.

With reference to FIG. 3, the spinneret 30 of the second embodiment will be described.

As shown in FIG. 3, in the spinneret 30, a solution holding portion 32 b that is a hollow portion having a cross section larger than that of the solution nozzle 32 is provided on the upstream side of the solution nozzle 32. In general, since the cross section of the solution nozzle 32 is as small as, for example, about 0.5 mm, it may be difficult to process through the entire thickness of the spinneret. Therefore, providing such a solution holding part 32b is preferable because the processing thickness of the solution nozzle 32 can be kept small.

In FIG. 3, the hollow portion 32b having such a large cross section is provided on the upstream side of the solution nozzle 32. Alternatively, it may be provided on the upstream side of the hot air nozzle 34, or both in a range where the hollow portions do not collide with each other. It may be provided.

With reference to FIG.4 and FIG.5, the spinneret 40 of 3rd Embodiment is demonstrated.

As shown in FIGS. 4 and 5, a solution nozzle 42 for discharging a polymer solution and a hot air nozzle 44 for blowing hot air gas are formed inside the spinneret 40.
Here, in the spinneret 40, the solution nozzle 42 is inclined.
On the other hand, the hot air nozzle 44 has a tapered portion 44a, a portion of which is tapered near the base lower surface 40a.
Thereby, even if the amount of hot air gas blown from the hot air nozzle 44 is small, the polymer solution discharged from the solution nozzle 42 is instantly solidified by the hot air gas blown along the tapered portion 44a of the hot air nozzle and effectively By drawing, ultrafine fibers such as nanofibers composed of fine fibers can be obtained.

The tapered portion 44a does not need to be provided on the entire periphery of the outlet side of the hot air nozzle 44, and is preferably provided at least on the side closest to the solution nozzle 42, and when the hot air nozzle 44 or the solution nozzle 42 has a circular cross section. , It is preferable to have the same width as either diameter.
Further, in FIG. 4, the tapered portion 44a, the central axis and the angle theta ₂ formed by the taper direction of the hot air nozzle is preferably within 35 degrees, more preferably within 25 degrees, more preferably within 15 degrees. If it exceeds 35 degrees, the polymer fiber is not sufficiently stretched by hot air gas, and it becomes difficult to obtain ultrafine fibers such as nanofibers made of fine fibers.
4 and 5, the tapered shape 44 a is provided on the base lower surface 40 a so as to be substantially in contact with the outlet of the solution nozzle 42, but the angle θ ₂ is reduced so as to approach the outlet of the solution nozzle 42. It may be provided.

As described above, in FIG. 4 and FIG. 5, the case where at least a part of the blowing portion of the hot air nozzle is tapered using the spinneret of the first embodiment has been described, but the spinneret of the second embodiment is used. It can be applied in the same way.

A spinneret 50 according to a fourth embodiment will be described with reference to FIG.

As shown in FIG. 6, the inside of the spinneret 50 solution nozzle 52 for discharging a polymer solution is provided a number on a circumference having a diameter D _1. Furthermore, although not shown in figure, the hot air nozzle which blows out hot air is arrange | positioned at each solution nozzle 52. FIG. The hot air nozzle is close to the solution nozzle 52 and is provided so that the blowing direction of the hot air nozzle and the discharge direction of the solution nozzle 52 intersect below the base lower surface 50a. Thereby, even if the amount of hot air gas blown out from each hot air nozzle is small, ultrafine fibers such as nanofibers made of fine fibers drawn by the hot air gas blown out from each solution nozzle 52 are blown out. Is excellent in productivity. In addition, since the arrangement of the hot air nozzles can be flexible, it is advantageous when the solution nozzles are provided at a high density.

The outer shape of the spinneret 50 does not necessarily have a circular cross section, and may be an ellipse, a polygon such as a rectangle or a hexagon. From the viewpoint of ease of processing of the spinneret, a circular shape is preferable.

In FIG. 6, 12 solution nozzles 52 are provided on the circumference. However, more solution nozzles 52 may be provided according to the outer shape and dimensions of the spinneret 50.
Here, the distance between adjacent solution nozzles 52 is preferably 2 mm to 12 mm, and more preferably 3 mm to 10 mm. If it is less than 2 mm, the spinning is not stable due to interference with the adjacent solution nozzle, and if it exceeds 12 mm, the number of solution nozzles is small and the productivity is lowered.

A spinneret 60 of the fifth embodiment will be described with reference to FIGS.

As shown in FIG. 7, the inside of the spinneret 60 solution nozzle 62 for discharging a polymer solution is provided a number on a circumference having a diameter D _1. Furthermore, a number of hot air nozzles 64 are arranged close to each solution nozzle 62 onto the circumference of diameter D ₂ which has the same center as the circle solution nozzle 62 is disposed.

Thereby, even if the amount of hot air gas blown out from each hot air nozzle is small, the polymer solution discharged from each solution nozzle 62 is stretched by the hot air gas blown out, and nanofibers made of fine fibers, etc. Since many ultrafine fibers can be obtained, it is excellent in productivity.

Further, the spinneret 60, as shown in FIG. 8, in the thickness direction of the circumference around the diameter D ₁ of the introduction path of the polymer solution, while the thickness direction in the vicinity of the circumference of the introduction path of the diameter D ₂ of the hot gas in, it has been arranged separately each diameter D ₂ is smaller than the diameter D _1.
By taking such an arrangement, it becomes easy to separate the introduction paths of the polymer solution and the hot air gas, which is advantageous for the processing and miniaturization of the spinneret.

7 and 8, a tapered portion 64 a is provided at the blowing portion of the hot air nozzle 64. Thereby, the discharged polymer solution is effectively stretched by the hot air gas.
Moreover, in FIG. 7, since the hot air introduction port 300b connected to the hot air nozzle 64 is provided from the side surface portion to the center portion, the liquid nozzle and the hot air nozzle located at the position interfering with the hot air nozzle are omitted. In order to avoid this, the hot air inlet 300b may be moved to the upper surface of the base, which is the opposite surface of the lower surface of the base.

In FIG. 7, the hot air nozzle 64 has a circular cross section, but may be an ellipse, a polygon such as a quadrangle or a hexagon. Also, may be a shape which is curved so as to follow an elongated rectangle on the circumference of diameter D _2, in this case, preferably it is possible to prevent fine fibers discharged dive inside the circumference of the diameter D ₂ .

In the spinneret 60 have been described above, the diameter D ₂ is a configuration when the diameter D ₁ is smaller than.
Conversely, even if the diameter D ₂ greater than the diameter D _1, also ultrafine fibers such as nanofibers made of fine fibers can be obtained a large number of, also, it facilitates isolation of each introduction path of the polymer solution and the hot gas And so on.

With reference to FIG. 9, the spinneret 70 of the sixth embodiment will be described.

As shown in FIG. 9, the inside of the spinneret 70 solution nozzle 72 for discharging a polymer solution is provided a number on the straight line l _1. Further, each solution nozzle 72 is provided with a hot air nozzle 74 for blowing hot air. The hot air nozzle 74 is close to the solution nozzle 72 and is provided so that the blowing direction of the hot air nozzle 74 and the discharge direction of the solution nozzle 72 intersect below the base lower surface 70a. Thereby, even if the amount of hot air gas blown out from each hot air nozzle is small, ultrafine fibers such as nanofibers made of fine fibers drawn by the hot air gas blown out from each solution nozzle 72 are blown out. Is excellent in productivity. Further, the arrangement of the hot air nozzles can be made flexible, which is advantageous when the solution nozzles are provided at a high density, and is preferable for producing a wide nonwoven fabric made of ultrafine fibers such as nanofibers.

The outer shape of the spinneret 70 is preferably a quadrilateral shape with an elongated cross section, but is not particularly limited thereto.

The distance between the adjacent solution nozzles 72 is preferably 2 mm to 12 mm, and more preferably 3 mm to 10 mm. If it is less than 2 mm, the spinning is not stable due to interference with the adjacent solution nozzle, and if it exceeds 12 mm, the number of solution nozzles is small and the productivity is lowered.

FIG. 10 shows an ultrafine fiber manufacturing apparatus provided with a plurality of spinnerets 60 shown in FIG. The polymer solution supplied from the polymer solution supply device is discharged in the form of a fiber from the solution nozzle 62 formed in the spinneret 60 through the solution introduction pipe 200a through the solution introduction port 200b. On the other hand, the hot air gas emitted from the hot air generating device is blown out from the hot air introduction pipe 300a through the hot air introduction port 300b and from the hot air nozzles 64 formed in the spinning nozzle 60. Thereby, the polymer solution discharged from the solution nozzle 62 is drawn while being instantly solidified to obtain ultrafine fibers such as nanofibers which are drawn and refined.

Further, as shown in FIG. 10, a mesh belt conveyor is provided below the spinneret 60, and ultrafine fibers such as micronized nanofibers are collected while being sandwiched on the running belt. Thus, a laminate of ultrafine fibers is formed.

In FIG. 10, three spinnerets 60 are provided in the width direction, but a larger number may be provided to increase productivity.
Further, a polymer solution composed of the same raw material polymer may be supplied to the plurality of spinnerets 60. On the other hand, by supplying a polymer solution obtained by dissolving a raw material polymer having different types and characteristics for each spinneret 60 in a solvent, it is possible to obtain ultrafine fibers composed of composite nanofibers.

FIG. 11 shows a nanofiber manufacturing apparatus provided with a plurality of spinnerets 70 shown in FIG. The polymer solution supplied from the polymer solution supply device is discharged in the form of fibers from a solution nozzle 72 formed in the spinneret 70 through a solution inlet 210b from a solution inlet pipe 210a. On the other hand, the hot air gas emitted from the hot air generator is blown out from the hot air nozzle 74 formed in the spinneret 70 through the hot air introduction pipe 310a through the hot air introduction port 310b. Thereby, the polymer solution discharged from the solution nozzle 72 is drawn while being instantly solidified to obtain nanofibers that are drawn and refined.

Further, as shown in FIG. 11, a mesh-shaped belt conveyor is provided below the spinneret 70, and the micronized fibers are collected while being pinched on the running belt. Is formed.

In FIG. 11, three spinnerets 70 are provided in the traveling direction of the belt conveyor, but a larger number may be provided to increase productivity.
Moreover, a polymer solution made of the same kind of raw material polymer may be supplied to the plurality of spinnerets 70. On the other hand, by supplying polymer solutions made of raw material polymers having different types and characteristics for each spinneret 60, ultrafine fibers made of composite nanofibers can be obtained.

20, 30, 40, 50, 60, 70: Spinneret 20a, 30a, 40a, 50a, 60a, 70a: Bottom of the base 22, 32, 42, 52, 62, 72: Solution nozzles 24, 34, 44, 64, 74: Hot air nozzle 32b: Solution holding part 44a, 64a: Hot air nozzle taper part 200: Polymer solution supply apparatus 200a, 210a: Solution introduction pipe 200b: Solution introduction port 300: Hot air generation apparatus 300a, 310a: Hot air introduction pipe 300b: Hot air inlet

Claims (6)

A spinneret comprising one or more solution nozzles capable of discharging a polymer solution obtained by dissolving a raw material polymer in a solvent, and one or more hot air nozzles for blowing hot air to the polymer solution discharged from the solution nozzle and drawing it into a fiber shape. There,
It said solution nozzle and the hot air nozzle, Ri columnar hollow body der each having a constant cross-sectional shape, close to each other,
The central axis of the solution nozzle and the central axis of the hot air nozzle exist on the same plane, and the extension line of the central axis of the solution nozzle and the extension line of the central axis of the hot air nozzle intersect on the lower side of the lower surface of the base. A spinneret characterized by being arranged as follows. The spinneret according to claim 1, wherein at least a part of the blowing portion of the hot air nozzle has a tapered shape. Spinneret according to claim 1 or claim 2 the plurality of the solution nozzle, characterized in that it is arranged on the circumference of the diameter D _1. A plurality of the hot air nozzle, together with the solution nozzle are arranged on a circumference of diameter D ₂ which has the same center as the circle is located, D ₂ is a being smaller or greater than D ₁ The spinneret according to claim 3. The spinneret according to claim 1 or 2, wherein the plurality of solution nozzles are arranged on a straight line. A spinneret according to any one of claims 1 to 5,
An apparatus for producing ultrafine fibers, wherein a polymer solution is discharged from the solution nozzle, hot air is blown out from the hot air nozzle to the discharged polymer solution, and the polymer solution is stretched into a fine fiber shape and deposited in a collecting portion.

Images