JP5004898B2 - Nonwoven manufacturing method - Google Patents

Description

  The present invention relates to a method for producing a nonwoven fabric.

  If the fiber diameter of the fibers that make up the nonwoven fabric is small, the fiber diameter of the fibers that make up the nonwoven fabric is excellent because it has excellent performance such as separation performance, liquid retention performance, wiping performance, concealment performance, insulation performance, or flexibility. Is preferably small. As a method for producing a nonwoven fabric composed of fibers having such a small fiber diameter, the spinning solution is discharged from a nozzle, an electric field is applied to the discharged spinning solution, the spinning solution is stretched, and the diameter of the spinning solution is reduced. A so-called electrospinning method is known in which a non-woven fabric is directly collected. According to this electrospinning method, a nonwoven fabric made of fibers having an average fiber diameter of 1 μm or less can be produced. In this electrostatic spinning method, in order to apply an electric field to the spinning solution, it is necessary to apply a high voltage to the nozzle or the collector, which not only complicates the apparatus but also wastes energy.

  As a spinning device capable of improving such a point, as shown in FIG. 2, “a device for forming a non-woven mat of nanofibers by using a compressed gas flow is the first (12), 2 (22) and third (32) members, each having a supply end (14, 24, 34) and an opposing outlet end (16, 26, 36), the second member (22) being the second. Adjacent to one member (12) The outlet end (26) of the second member (22) extends beyond the outlet end (16) of the first member (12). (22) The member defines a first supply slit (18) and the third member (32) extends from the second member (22) of the first member (12) to the first member (12) on the opposite side. Located adjacent to each other, the first (12) and third (32) members define a first gas slit (38) and the first ( 2) The outlet ends (16, 26, 36) of the second (22) and third (32) members define a gas jet space (20) Nanofiber non-woven by using a compressed gas flow. A method of forming a mat is also included "(Patent Document 1). Since this apparatus does not need to apply a high voltage, it can solve the above-mentioned problems. However, in this apparatus, since the flat plate-like first, second and third members are provided in parallel, the compressed gas is allowed to act on the sheet-like spinning solution, and it is difficult to form a fiber shape. It was thought that only a thick fiber could be formed even if it became a fiber shape because it contained many droplets.

  As a similar spinning device, “a center tube, a first supply tube located concentrically and spaced apart from the center tube, an intermediate gas tube located concentrically and spaced apart from the first supply tube, and concentric and separated from the intermediate gas tube. The center tube and the first supply tube form a first annular column, the intermediate gas tube and the first supply tube form a second annular column, and the intermediate gas tube and the first supply tube are spaced apart from each other. 2 supply tubes form a third annular column, a first gas jet space is formed at the downstream end of the center tube and the first supply tube, and a second gas jet space is downstream of the intermediate gas tube and the second supply tube. A nanofiber manufacturing apparatus using compressed gas, which is positioned so as to be formed at the side end portion ”has been proposed (Patent Document 2).Since this manufacturing apparatus does not need to apply a high voltage, the above-mentioned problems can be solved. However, even in this apparatus, since the gas jet acts on the spinning solution discharged in an annular shape, the spinning is unstable, the fiber shape is difficult to be formed, and many droplets are contained.

JP 2005-515316 A (summary, Table 1, etc.) US Pat. No. 6,520,425 (summary, FIG. 2 etc.)

  Accordingly, the applicant of the present application stated that “a spinning device that satisfies the following conditions, having a liquid discharge portion that can discharge a spinning solution and a gas discharge portion that is located upstream of the liquid discharge portion and can discharge gas. (1) It has a liquid columnar hollow part (Hl) with the liquid discharge part as an end part (2) It has a gas columnar hollow part (Hg) with the gas discharge part as an end part (3) Liquid columnar hollow part The liquid virtual columnar part (Hvl) extending (Hl) and the gas virtual columnar part (Hvg) extending the gas columnar hollow part (Hg) are close to each other (4) of the liquid columnar hollow part (Hl) The discharge direction central axis and the gas column hollow portion (Hg) are parallel to the discharge direction central axis. (5) When cut along a plane perpendicular to the center axis of the gas column hollow portion (Hg) The distance between the outer circumference of the cut surface of the columnar hollow portion (Hg) and the outer circumference of the cut surface of the columnar hollow portion for liquid (Hl) is the maximum. A short straight line, thought "it is possible to draw only one. According to this spinning device, the spinning solution discharged from the liquid discharging unit and the gas discharged from the gas discharging unit are close and parallel to each other, and the spinning solution has one shearing force due to the gas and the accompanying airflow. Therefore, the thinned fiber can be spun stably. Further, since it is not necessary to apply a high voltage to the spinning solution, the apparatus is simple and advantageous in terms of energy. When producing a nonwoven fabric by collecting the fibers spun using this spinning device to produce a nonwoven fabric, it is difficult to fiberize unless a certain amount of gas is applied at a high speed, so that a certain amount of gas acts at a high speed. However, when such a gas is applied, there is a tendency that fibers accumulated on the collector are easily scattered.

  Therefore, in order to produce a nonwoven fabric in which fibers having different fiber diameters are mixed, or in order to produce a nonwoven fabric in which fibers having different resin compositions are mixed, increasing the spinning device, the gas discharge amount increases accordingly, It was difficult to produce a nonwoven fabric with excellent texture in which the amount of scattered fibers increased and different types of fibers were uniformly mixed. In addition, when the amount of scattered fibers increased, the scattered fibers adhered to the liquid discharge portion of the spinning device, hindering fiber formation, and the productivity deteriorated. In order to suppress the amount of scattered fibers, it is only necessary to increase the size of the suction device for sucking the fibers, but this is disadvantageous in terms of energy, and if the suction force is strong, only a thin nonwoven fabric can be produced. Occurred.

  The present invention has been made in view of the above-mentioned problems, and a nonwoven fabric excellent in texture in which two or more kinds of fibers having different fiber diameters such as fiber diameter and resin composition are uniformly mixed, with small energy, It is an object of the present invention to provide a method that can be manufactured with high productivity. The present invention also relates to a method capable of producing a thin nonwoven fabric to a thick nonwoven fabric.

  The invention according to claim 1 of the present invention includes: “two or more liquid discharge portions that can discharge the spinning liquid; and one gas discharge portion that is located upstream of any of the liquid discharge portions and can discharge gas. Using a spinning device that satisfies the following conditions, the spinning liquid is discharged from the liquid discharge section under two or more discharge conditions to form a fiber, and the collected body is accumulated on the nonwoven fabric. Manufacturing method: (1) Each of the liquid discharge portions has a liquid columnar hollow portion having an end portion (2) The gas columnar hollow portion has an end portion of the gas discharge portion (3) A liquid columnar hollow portion is provided Each extended liquid virtual columnar part and the gas virtual columnar part extended from the gas columnar hollow part are close to each other. (4) Each discharge direction central axis of the liquid columnar hollow part and the discharge direction of the gas columnar hollow part (5) With respect to the central axis of the columnar hollow for gas When cutting in a straight plane, only one straight line with the shortest distance between the outer periphery of the cut surface of the gas columnar hollow portion and the outer periphery of the cut surface of the liquid columnar hollow portion can be drawn in any combination. It can be done.

  The invention according to claim 2 of the present invention is “the method for producing a nonwoven fabric according to claim 1, wherein spinning solutions having different concentrations are discharged”.

  The invention according to claim 3 of the present invention is “the method for producing a nonwoven fabric according to claim 1, wherein a spinning solution having a different polymer is discharged”.

  The invention according to claim 4 of the present invention is “the method for producing a nonwoven fabric according to claim 1, wherein a spinning solution having a different solvent is discharged”.

  In the invention according to claim 1 of the present invention, the spinning solution discharged from each liquid discharge portion and the gas discharged from the gas discharge portion are close to each other and parallel to each other, and each spinning solution has a gas In addition, since the shearing force due to the accompanying airflow acts in a straight line, it is possible to spin a fiber having a reduced diameter. In addition, the spinning solution discharged from two or more liquid discharge parts can be made into fiber with the gas discharged from one gas discharge part, and the amount of gas can be reduced, thereby suppressing fiber scattering. Thus, a non-woven fabric with excellent texture can be produced with high productivity. In addition, the amount of gas can be reduced, it is not necessary to increase the size of the suction device, and it is not necessary to apply a high voltage to each spinning solution, which is advantageous in terms of energy. Further, since the amount of gas can be reduced and there is no need to increase the suction force, it is possible to manufacture from a thin nonwoven fabric to a thick nonwoven fabric. Furthermore, since the spinning solution is discharged from the liquid discharge section under two or more discharge conditions to produce fibers, a nonwoven fabric with excellent texture in which two or more types of fibers with different fiber diameters, resin compositions, etc. are mixed together is manufactured. can do.

  The invention according to claim 2 of the present invention can produce a nonwoven fabric excellent in texture in which two or more types of fibers having different fiber diameters are uniformly mixed by discharging spinning solutions having different concentrations.

  The invention according to claim 3 of the present invention can produce a nonwoven fabric with excellent texture in which two or more kinds of fibers having different resin compositions are uniformly mixed by discharging spinning liquids having different polymers.

  The invention according to claim 4 of the present invention can produce a nonwoven fabric with excellent texture in which two or more kinds of fibers having different fiber diameters are uniformly mixed by discharging spinning solutions having different solvents.

  FIG. 1 is a cross-sectional view taken along the plane C in FIG. 1 and FIG. 1, which is an enlarged perspective view of a spinning device having two liquid discharge portions and one gas discharge portion. This will be described with reference to FIG.

The spinning device used in the present invention includes a first liquid discharge nozzle Nl ₁ having a first liquid discharge part El ₁ capable of discharging a spinning liquid at one end, and a second liquid discharge part El ₂ capable of discharging the spinning liquid. The second liquid discharge nozzle Nl ₂ at one end is in contact with the outer wall surface so as to sandwich the gas discharge nozzle Ng having a gas discharge portion Eg at one end that can discharge gas. The gas discharge part Eg is at a position upstream of both the first liquid discharge part El ₁ and the second liquid discharge part El ₂ . The first liquid discharge nozzle Nl ₁ has a first liquid columnar hollow part Hl ₁ with the first liquid discharge part El ₁ as an end, and the second liquid discharge nozzle Nl ₂ is the second liquid discharge part El _2. the a second liquid columnar hollow for Hl ₂ to end, the gas discharge nozzle Ng has a gas columnar hollow for Hg to end the gas discharge portion Eg. Further, wherein the first liquid columnar hollow for the first liquid virtual columnar portion Hvl ₁ and extended gas virtual columnar portion Hvg the columnar hollow Hg for the gas extending the Hl _1, the first liquid discharge nozzle Nl ₁ It is in a state close to a distance corresponding to the sum of the wall thickness of the wall and the gas discharge nozzle Ng, second liquid virtual columnar portion Hvl ₂ and for the gas extending the columnar hollow Hl ₂ for the second liquid the columnar hollow gas virtual columnar portion Hvg which extended Hg, is in a state close to a distance corresponding to the sum of the wall thicknesses of the second liquid wall thickness of the discharge nozzle Nl ₂ and the gas discharge nozzle Ng. Moreover, the first liquid columnar hollow part Hl ₁ has a relationship in which the first discharge direction central axis Al ₁ and the gas columnar hollow part Hg discharge direction central axis Ag are in parallel, and the second liquid columnar hollow part Hl and discharge direction central axis Ag of the _second second ejection direction central axis Al ₂ gas columnar hollow for Hg is in a parallel relationship. Further, when the gas columnar hollow part Hg is cut along a plane perpendicular to the central axis Ag of the gas columnar hollow part Hg, the outer shape of the cut surface of the gas columnar hollow part Hg is circular, and the first liquid columnar hollow part Hl ₁ , both the outer shape of the cut surface of the second liquid columnar hollow for Hl ₂ is circular, the distance between the outer periphery of the outer periphery cut surface of the columnar hollow Hl ₁ for the first liquid in the cut surface of the columnar hollow for gas (Hg) There the shortest straight line L1, the shortest straight line L2 distance between the outer periphery of the cut surface peripheral to the cutting surface of the columnar hollow Hl ₂ for the second liquid of columnar hollow for gas (Hg), be drawn only one It is in a ready state (see FIG. 3A).

Therefore, when the spinning liquid is supplied to the first liquid discharge nozzle Nl ₁ and the second liquid discharge nozzle Nl ₂ of the spinning apparatus as shown in FIG. 1 and the gas is supplied to the gas discharge nozzle Ng, the spinning liquid is used for the first liquid. The _first hollow portion Hl ₁ and the second liquid columnar hollow portion Hl ₂ pass through the first liquid discharge portion El ₁ and the second liquid discharge portion El ₂ in the first axial direction of the first liquid columnar hollow portion Hl ₁ , respectively. At the same time as each is ejected in a second axial direction of the second liquid columnar hollow for Hl _2, gas is discharged in the axial direction of the gas columnar hollow for Hg from the street ejecting gas Eg the columnar hollow for gas (Hg) . The discharged gas and each discharged spinning solution are close to each other, and in the immediate vicinity of each liquid discharging portion, the central axis Ag of the discharged gas and the central axes Al ₁ and Al _{2 of} each discharged spinning solution. Are in a parallel relationship, and on the C plane, the discharged gas and the discharged spinning solution have one closest point in any combination, that is, any spinning solution. also subjected to shearing action by the gas and the accompanying airstream on one straight line shape, diameter reduction while the first solution for a first axis direction of the columnar hollow Hl _1, a second liquid columnar hollow for Hl ₂ second axial At the same time, the solvent of the spinning solution volatilizes and fiberizes. In the present invention, the discharge conditions from the first liquid discharge nozzle Nl ₁ and the second liquid discharge nozzle Nl ₂ are different. Thus, when a nonwoven fabric is manufactured using the spinning device of FIG. 1, two spinning solutions can be spun into fiber by one gas flow, and the amount of gas can be reduced. A non-woven fabric with excellent texture can be produced with good productivity by suppressing scattering. The amount of gas can be reduced, it is not necessary to increase the size of the suction device, and it is not necessary to apply a high voltage to each spinning solution, which is advantageous in terms of energy. In addition, since it is not necessary to increase the suction force, it is possible to manufacture from a thin nonwoven fabric to a thick nonwoven fabric. Furthermore, since the discharge conditions from the first liquid discharge nozzle Nl ₁ and the second liquid discharge nozzle Nl ₂ are different and the gas acting on the discharged spinning liquid is the same, different types of fibers are spun. As a result, it is possible to produce a nonwoven fabric with excellent texture in which different types of fibers are uniformly mixed.

The first liquid discharge nozzle Nl ₁ and the second liquid discharge nozzle Nl ₂ need only be capable of discharging the spinning liquid, and the outer shapes of the first liquid discharge part El ₁ and the second liquid discharge part El ₂ are not particularly limited. For example, the shape may be a circle, an oval, an ellipse, or a polygon (for example, a triangle, a quadrangle, or a hexagon). A circular shape is preferable so that droplets are not easily generated. That is, if the outer shapes of the first liquid discharge part El ₁ and the second liquid discharge part El ₂ are circular, the gas columnar hollow when cut by a plane perpendicular to the central axis Ag of the gas columnar hollow part Hg. The straight line L1, L2 having the shortest distance between the outer periphery of the cut surface of the part Hg and the outer periphery of the liquid columnar hollow portions Hl ₁ , Hl ₂ is likely to be in a state where only one line can be drawn in any combination. For this reason, the discharged spinning solution is subjected to the shearing action of the gas and the accompanying airflow in a single straight line, and is unlikely to generate droplets. Note that the outer shape of the first liquid discharge unit El ₁ and the second liquid discharge unit El ₂ may be the same or different, but both are preferably circular. If the outer shapes of the first liquid discharge part El ₁ and the second liquid discharge part El ₂ are different, the shearing action of the gas and the accompanying air flow causes the spinning liquid discharged from the first liquid discharge part El ₁ and the second liquid discharge part. Since the spinning solution discharged from El ₂ is different, different types of fibers can be spun.

When the shapes of the first liquid discharge unit El ₁ and the second liquid discharge unit El ₂ are polygons, the gas and the accompanying liquid are arranged by arranging one corner of the polygon on the gas discharge nozzle Ng side. It is preferable that the shearing action of the air current is received in a single straight line to make it difficult for droplets to form. That is, when cut along a plane perpendicular to the central axis Ag of the gas columnar hollow portion Hg, the outer periphery of the cut surface of the gas columnar hollow portion Hg, the first liquid columnar hollow portion Hl ₁ , and the second liquid columnar shape. the hollow portion distance is the shortest straight line between the outer periphery of the cut surface of Hl ₂ (FIG. 3 (a) ~ (L1 in e), L2), in any combination, first to be able to draw only one 1 When the liquid discharge nozzle Nl ₁ and the second liquid discharge nozzle Nl ₂ are arranged, the spinning liquid is subjected to the shearing action of the gas and the accompanying airflow in a single straight line, can be stably spun, and it is difficult to generate droplets. Therefore, if the shape of the gas discharge part Eg is circular, the sides of the polygonal first liquid discharge part El ₁ and the second liquid discharge part El ₂ can be arranged on the gas discharge nozzle Ng side. Yes (see FIG. 3 (e)).

Further, although not the size of the first liquid ejection unit El ₁ and the second liquid ejection unit El ₂ is also limited particularly, but is preferably either a 0.01 to 20 mM ^2, is 0.01 to 2 mm ² Is more preferable. If it is smaller than 0.01 mm ² , it tends to be difficult to discharge a spinning solution having a high viscosity, and if it exceeds 20 mm ² , it becomes difficult to make the action of the gas and the accompanying air flow straight. This is because there is a tendency that spinning cannot be performed stably. Even when the sizes of the first liquid discharge part El ₁ and the second liquid discharge part El ₂ are different, the shearing action of the gas and the accompanying air flow causes the spinning liquid and the second liquid discharged from the first liquid discharge part El _1. since different between the discharged from the discharge unit El ₂ spinning solution can be spun different types of fibers.

The first liquid discharge nozzle Nl ₁ and the second liquid discharge nozzle Nl ₂ may be made of metal or resin, and the material is not particularly limited. A metal or resin tube can also be used. Further, in FIG. 1, the cylindrical first liquid discharge nozzle Nl ₁ and the second liquid discharge nozzle Nl ₂ are illustrated, but an acute angle nozzle whose tip is cut with an inclination may be used. This acute angle nozzle is effective when the spinning solution has a high viscosity. When such an acute angle nozzle is used, if the sharp side is the gas discharge nozzle side, it is easy to be subjected to the shearing action of the gas and the accompanying airflow, and can be stably fiberized.

In FIG. 1, two of the first liquid discharge nozzle Nl ₁ and the second liquid discharge nozzle Nl ₂ are illustrated, but the number of liquid discharge nozzles is not necessarily two, and three or more. (See FIG. 4). The greater the number of liquid discharge nozzles, the more efficiently the gas can be used and the nonwoven fabric can be produced with good productivity.

The gas discharge nozzle Ng only needs to be capable of discharging gas, and the shape of the gas discharge portion Eg is not particularly limited. For example, a circle, an oval, an ellipse, a polygon (for example, a triangle, a rectangle, a hexagon) However, no matter how each liquid discharge part is arranged with respect to the gas discharge part, the gas discharged from the gas discharge part and the accompanying liquid are discharged into each spinning liquid discharged from each liquid discharge part. A circular shape is preferred so that the shearing force generated by the air current is applied in a straight line to facilitate spinning of the thinned fiber. When the shape of the gas discharge portion Eg is a polygon, one corner of the polygon is on the first liquid discharge nozzle Nl ₁ side, and the other corner is on the second liquid discharge nozzle Nl ₂ side. By arranging, the shearing action of the gas and the accompanying airflow becomes easy to work. That is, as described above, when cut along a plane perpendicular to the central axis Ag of the gas columnar hollow part Hg, the outer periphery of the cut surface of the gas columnar hollow part Hg and the first liquid columnar hollow part Hl ₁ , The first liquid discharge nozzle Nl ₁ so that only one straight line L1, L2 having the shortest distance from the outer periphery of the cut surface of the two liquid columnar hollow part Hl ₂ can be drawn in any combination. When the second liquid discharge nozzle Nl ₂ is disposed (see FIGS. 3C to 3D), the spinning liquid is subjected to the shearing action of the gas and the accompanying airflow in a single straight line, and the liquid droplets are hardly generated. .

Although not limited to particular also the size of the gas discharge portion Eg, is preferably from 0.01～79Mm ^2, and more preferably 0.015~20mm ^2. When less than 0.01 mm ^2, it becomes difficult to exert a shearing action across the spinning solution discharged, stabilized with because it tends to be difficult to fiberizing, when more than 79 mm ² Shear This is because a sufficient wind speed is necessary to make the action work, and a large amount of gas is required, which is uneconomical.

  The gas discharge nozzle Ng may be made of metal or resin, and its material is not particularly limited. In addition, a tube made of metal or resin can be used instead of the gas discharge nozzle.

The gas discharge nozzle Ng is disposed at a position where the gas discharge portion Eg is located upstream of the first liquid discharge portion El ₁ and the second liquid discharge portion El ₂ (spinning liquid supply side). It is possible to prevent the spinning solution from winding up around the part El ₁ and the second liquid discharge part El ₂ . Therefore, stable spinning for a long time is possible without polluting the liquid discharge part. The distance between the gas discharge part Eg and the first liquid discharge part El ₁ or the second liquid discharge part El ₂ is not particularly limited, but is preferably 10 mm or less, and more preferably 5 mm or less. . This is because if it exceeds 10 mm, the shearing force of the gas and the accompanying airflow in the first liquid discharge part El ₁ or the second liquid discharge part El ₂ becomes insufficient, and it tends to be difficult to fiberize. The lower limit of the distance between the gas discharge part Eg and the first liquid discharge part El ₁ and the second liquid discharge part El ₂ is not particularly limited, and the gas discharge part Eg, the first liquid discharge part El ₁ and the second liquid discharge are not limited. It is sufficient if the part El ₂ does not match.

The distance between the gas discharge part Eg and the first liquid discharge part El ₁ or the second liquid discharge part El ₂ may be the same or different, but if they are the same, the same for each spinning liquid. A shearing force of a certain degree can be applied, and spinning is possible stably. Note that if the distance between the gas discharge part Eg and the first liquid discharge part El ₁ and the distance between the gas discharge part Eg and the second liquid discharge part El ₂ are different, the shearing action of the gas and the accompanying airflow is caused by the first liquid discharge part. Since the spinning liquid discharged from El ₁ and the spinning liquid discharged from the second liquid discharge part El ₂ are different, different types of fibers can be spun.

First liquid columnar hollow for Hl ₁ and the second liquid columnar hollow for Hl ₂ is a passing path of the spinning solution, the shape at the time of discharge of the spinning liquid to shape, the columnar hollow for gas (Hg) in the passage path of the gas There is a shape when gas is discharged. In the present invention, any of the first liquid columnar hollow part Hl ₁ , the second liquid columnar hollow part Hl ₂ , and the gas columnar hollow part Hg can form a columnar spinning liquid or gas. A shearing action can be sufficiently exerted on each spinning solution, and fiber can be stably formed.

The first liquid virtual columnar part Hvl ₁ extending from the first liquid columnar hollow part Hl ₁ is a flight path immediately after the discharge of the spinning solution discharged from the first liquid discharge part El ₁ , and the second liquid columnar part The second liquid virtual columnar part Hvl ₂ extending the hollow part Hl ₂ is a flight path immediately after the spinning liquid discharged from the second liquid discharge part El _{2 is} discharged, and the gas virtual columnar part extending the gas columnar hollow part Hg. Part Hvg is an ejection path immediately after ejection of the gas ejected from the gas ejection part Eg. The first liquid distance between the virtual columnar portion Hvl ₁ and the gas virtual columnar portion Hvg corresponds to the sum of the wall thicknesses of the first liquid ejection wall thickness of the nozzle Nl ₁ and the gas discharge nozzle Ng, second liquid virtual columnar portion Hvl ₂ is equivalent to the sum of the wall thickness of the second liquid discharge nozzle Nl _{2 and} the wall thickness of the gas discharge nozzle Ng, but the distance is preferably 2 mm or less. The following is more preferable. This is because if it exceeds 2 mm, the shearing force of the gas and the accompanying airflow hardly acts, and it tends to be difficult to be fiberized.

All of the first liquid virtual columnar part Hvl ₁ , the second liquid virtual columnar part Hvl ₂ , and the gas virtual columnar part Hvg have a solid columnar shape. For example, a state in which the cylindrical first or second liquid virtual part is covered with a hollow cylindrical gas virtual part, or a state in which the cylindrical gas virtual part is covered with a hollow cylindrical first or second liquid virtual part When cut by a plane perpendicular to the center axis Ag of the gas virtual columnar part Hvg, the outer periphery of the cut surface of the first or second liquid virtual part and the inner periphery of the cut surface of the gas virtual part, or gas As a result of being able to draw an infinite number of straight lines with the shortest distance between the outer circumference of the cut surface of the imaginary part and the inner circumference of the cut surface of the first or second liquid imaginary part, the gas and the accompanying airflow are changed at various points of the spinning solution. This is because shearing force acts, fiberization becomes insufficient, and droplets increase. This “virtual columnar portion” is a portion formed by extending the inner wall surface of the nozzle.

The first discharge direction central axis Al _{1 of} the first liquid columnar hollow part Hl ₁ is parallel to the discharge direction central axis Ag of the gas columnar hollow part Hg, and the second liquid columnar hollow part Hl ₂ for 2 and discharge direction central axis Ag of the ejection direction central axis Al ₂ gas columnar hollow for Hg are parallel, gas and the accompanying airstream acts on one straight line shape with respect to the discharged spinning solution, stable Thus, fibers can be formed. For example, the cylindrical first or second liquid hollow part is covered with a hollow cylindrical gas hollow part, or the cylindrical gas hollow part is covered with a hollow cylindrical first or second liquid hollow part. If the central axes coincide with each other as in the state, the shearing force of the gas and the accompanying air current cannot be applied to the spinning solution in a straight line, the fiberization becomes unstable, and the droplets Become more. In addition, when these central axes are in a crossing or twisting position, the shearing force due to the gas and the accompanying airflow does not act or even if it acts, the fibers cannot be formed stably. The term “parallel” means that the central axis in the discharge direction of the first or second liquid columnar hollow part and the central axis in the discharge direction of the gas columnar hollow part can be located on the same plane and are parallel to each other. It means that there is. Further, the “ejection direction central axis” is a straight line formed by connecting the center of the ejection part and the center of the cross section of the virtual columnar part.

When the spinning device used in the present invention is cut along a plane perpendicular to the central axis Ag of the gas columnar hollow part Hg, the outer periphery of the cut surface of the gas columnar hollow part Hg and the first liquid columnar hollow part Hl ₁ the distance between the outer periphery of the cut surface can draw only the shortest straight line L1 to one of the cut surface of the columnar hollow for gas (Hg) outer periphery and the outer periphery of the cut surface of the second liquid columnar hollow for Hl ₂ Only one straight line L2 having the shortest distance can be drawn. Such gas columnar hollow for gas and the accompanying airstream discharged from Hg is a spinning solution discharged from the columnar hollow Hl ₁ for the first liquid, discharged from the columnar hollow Hl ₂ for the second liquid spinning Since any one of the liquids can act in a straight line and exhibit a shearing action, it can be stably spun without producing droplets. For example, in the case where two straight lines can be drawn, the case of acting at one point and the case of acting at the other point are alternated. Droplets are generated and cannot be stably spun.

Although not shown in FIG. 1, the first liquid discharge nozzle Nl ₁ and the second liquid discharge nozzle Nl ₂ are made of a spinning liquid storage device (for example, a syringe, a stainless steel tank, a plastic tank, or a vinyl chloride resin, The gas discharge nozzle Ng is connected to a gas supply device (for example, a compressor, a gas cylinder, a blower, etc.).

  In FIG. 1, only one set of spinning devices is shown, but if two or more sets of spinning devices are arranged, the nonwoven fabric can be manufactured with high productivity.

In FIG. 1, the first liquid discharge nozzle Nl ₁ , the second liquid discharge nozzle Nl ₂ , and the gas discharge nozzle Ng are in a fixed state. However, as long as the relationship as described above is satisfied, the mode of FIG. It is not limited to. For example, the first liquid columnar hollow part Hl ₁ , the second liquid columnar hollow part Hl ₂ , and the gas columnar hollow part Hg may be perforated on a substrate having a step. The first liquid ejection unit El ₁ of the first liquid discharge nozzle Nl _1, the second liquid ejection unit El ₂ of the second liquid discharge nozzle Nl _2, and / or the position of the exit for ejecting gas (Eg) of the gas discharge nozzle Ng free It is also possible to provide a mechanism that can be adjusted.

  In the present invention, using such a spinning device, the spinning solution is discharged from the liquid discharging section under two or more discharge conditions to form a fiber, and is collected on the collecting body to produce a nonwoven fabric. This "two or more types of discharge conditions" means that they are not exactly the same. For example, the liquid discharge part has a different outer shape, the liquid discharge part has a different size, and the distance from the gas discharge part of the liquid discharge part is different. When the spinning solution discharge amount is different, the spinning solution concentration is different, the spinning solution constituent polymer is different, the spinning solution viscosity is different, the spinning solution solvent is different, and there are two or more spinning solution constituent polymers. Have different blending ratios, when there are two or more spinning solution constituent solvents, the blending ratios are different, the temperature of the spinning solution is different, and the types and / or amounts of additives added to the spinning solution are different. , Etc., one or more of these are different. Among these, even if the polymers constituting the spinning solution are the same, the concentration is different, or even if the polymers constituting the spinning solution are the same and the solvent is different, two or more types of fibers having different fiber diameters are mixed uniformly. The non-woven fabric with excellent texture can be produced, and when the polymers constituting the spinning solution are different, a non-woven fabric with excellent texture in which two or more kinds of fibers having different fiber-constituting polymers are uniformly mixed can be produced.

  The collecting body may be anything as long as the fibers can be directly accumulated. For example, a nonwoven fabric, a woven fabric, a knitted fabric, a net, a drum, a belt, or a flat plate can be used as the collecting body. In addition, since gas is discharged in the present invention, it is easy to collect the fibers on the collecting body by sucking the gas, and use a breathable collecting body so that the collected fibers are not disturbed. It is preferable to install a suction device on the side opposite to the spinning device side.

  It is preferable that such a collector is positioned facing the gas discharge part Eg of the spinning device because fibers can be reliably collected and a nonwoven fabric can be produced. In particular, it is preferable to arrange the collection body so that the collection surface of the collection body is positioned so as to be perpendicular to the central axis Ag of the gas discharge direction. In addition, even if the collector is arranged so that the collection surface of the collector is positioned so as to be parallel to the central axis Ag of the gas discharge direction, the flying direction is changed below the gravity direction where the flying force of the fiber disappears or the flying direction is changed. When the gas flow to be acted is applied, the fibers can be accumulated in the collector. Therefore, the gas discharge direction central axis Ag of the spinning device can be directed in a direction intersecting with gravity.

In the case where the collection body is arranged opposite to the gas discharge portion Eg of the spinning device, the distance between the collection body and the first liquid discharge portion El ₁ and the second liquid discharge portion El ₂ of the spinning device is determined by the discharge of the spinning solution. Although it does not specifically limit since it changes with quantity and gas flow velocity, It is preferable that it is 30-1000 mm. If the thickness is less than 30 mm, the solvent of the spinning solution is accumulated in a state where it is not sufficiently evaporated, and the fiber shape cannot be maintained after the accumulation, and a nonwoven fabric may not be obtained. Moreover, when it exceeds 1000 mm, the gas flow is disturbed, and the fibers tend to break and scatter easily.

  When manufacturing a nonwoven fabric by the method of this invention, it is preferable to implement in the spinning container which can accommodate a spinning device and a collection body. By carrying out in such a spinning container, scattering of the solvent volatilized from the spinning solution can be prevented, and in some cases, the solvent can be recovered and reused. Moreover, when manufacturing a nonwoven fabric in a spinning container, it is preferable to manufacture while discharging the gas in a spinning container. When spinning is performed, the solvent vapor concentration in the spinning vessel gradually increases, and the evaporation of the solvent is suppressed. Therefore, the fiber diameter tends to vary and the fiber becomes difficult to be fiberized. This is because the fluctuation of the average fiber diameter can be reduced by discharging the inner gas and keeping the solvent concentration in the spinning container constant. In addition, when the gas with adjusted temperature and humidity is supplied to the spinning vessel, the solvent vapor concentration can be stabilized and the variation in fiber diameter can be reduced.

  In the case of manufacturing a nonwoven fabric, a flow rate of 100 m / sec. It is preferable to discharge the above gas. From the gas discharge part Eg, a flow rate of 100 m / sec. This is because by discharging the gas described above, the generation of liquid droplets can be suppressed, and a nonwoven fabric containing fibers with a reduced diameter can be efficiently produced. Preferably, the flow rate is 150 m / sec. The above gas is discharged, more preferably a flow rate of 200 m / sec. The above gas is discharged. The upper limit of the gas flow rate is not particularly limited as long as it does not disturb the fibers accumulated on the collector. In order to discharge the gas having such a flow velocity, for example, the gas may be supplied from the compressor to the gas columnar hollow portion Hg. In addition, although the kind of gas is not specifically limited, air, nitrogen gas, argon gas, etc. can be used and it is economical when it is air among these. Further, these gases may contain a solvent vapor having affinity for the spinning solution or a solvent vapor having no affinity. By adjusting the vapor amount of the solvent, the solvent evaporation rate from each spinning solution and the solidification rate of each spinning solution can be controlled, and the spinning stability can be increased and the fiber diameter can be adjusted.

  Each spinning solution that can be used in the production method of the present invention is not particularly limited as long as the desired polymer is dissolved in a solvent. For example, polyethylene glycol, partially saponified polyvinyl alcohol, fully saponified polyvinyl alcohol, polyvinyl pyrrolidone, polylactic acid, polyester, polyglycolic acid, polyacrylonitrile, copolymerized polyacrylonitrile, polymethacrylic acid, polymethyl methacrylate, polycarbonate, polystyrene, polyamide, One or more polymers such as polyimide, polyethylene, or polypropylene are mixed with water, acetone, methanol, ethanol, propanol, isopropanol, tetrahydrofuran, dimethyl sulfoxide, 1,4-dioxane, pyridine, N, N-dimethylformamide, N , N-dimethylacetamide, N-methyl-2-pyrrolidone, acetonitrile, formic acid, toluene, benzene, cyclohexane, Cyclohexanone, carbon tetrachloride, can be used methylene chloride, chloroform, trichloroethane, ethylene carbonate, diethyl carbonate, which is dissolved in a solvent consisting of one or more such as propylene carbonate.

The viscosity of each spinning solution during spinning is preferably in the range of 10 to 10000 mPa · s, and more preferably in the range of 20 to 8000 mPa · s. When the viscosity is less than 10 mPa · s, the viscosity is too low and the spinnability tends to be difficult to become a fiber, and when the viscosity exceeds 10,000 mPa · s, the spinning solution is difficult to be drawn and tends to become a fiber. . Accordingly, even when the viscosity exceeds 10,000 mPa · s at room temperature, the viscosity can be increased by heating the spinning solution itself, the first liquid columnar hollow part H1 ₁ , and / or the second liquid columnar hollow part Hl _2. If it is within the range, it can be used. On the other hand, even if the viscosity is less than 10 mPa · s at room temperature, the above-mentioned viscosity range can be obtained by cooling the spinning solution itself, the first liquid columnar hollow part Hl ₁ , and / or the second liquid columnar hollow part Hl _2. If it fits in, you can use it. The “viscosity” in the present invention refers to a value at a shear rate of 100 s ⁻¹ measured at the same temperature as in spinning using a viscosity measuring device.

The discharge amount of each spinning liquid from the first liquid discharging part El ₁ and the second liquid discharging part El ₂ is not particularly limited because it varies depending on the viscosity and gas flow rate of each spinning liquid. It is preferably 100 cm ³ / hour.

  Examples of the present invention will be described below, but the present invention is not limited to the following examples.

Example 1
(Preparation of spinning solution)
A spinning solution A (viscosity (temperature: 23 ° C.): 500 mPa · s) in which polyacrylonitrile (manufactured by Aldrich) was dissolved in N, N-dimethylformamide to a concentration of 8 mass% was prepared.

  Further, a spinning solution B (viscosity (temperature: 23 ° C.): 1600 mPa · s) in which polyacrylonitrile (manufactured by Aldrich) was dissolved in N, N-dimethylformamide so as to have a concentration of 11 mass% was prepared.

(Preparation of non-woven fabric production equipment)
A manufacturing apparatus having the following configuration as shown in FIG. 1 was prepared.
(1) Spinning liquid storage part: Syringe (2) Air supply device: Compressor (3) First liquid discharge nozzle Nl ₁ : Metal (3) -1 First liquid discharge part El ₁ :
0.33 mm diameter (cross-sectional area: 0.086 mm ² ) circular shape (3) -2 first liquid columnar hollow portion H _{1 1} : 0.33 mm diameter cylindrical shape (3) -3 Nozzle outer diameter: 0.64 mm
(4) Second liquid discharge nozzle Nl ₂ : Metal (4) -1 Second liquid discharge part El ₂ :
0.33 mm diameter (cross-sectional area: 0.086 mm ² ) circular shape (4) -2 second liquid columnar hollow part Hl ₂ : 0.33 mm diameter cylindrical shape (4) -3 Nozzle outer diameter: 0.64 mm
(5) Gas discharge nozzle Ng: Metal (5) -1 Gas discharge portion Eg:
0.33 mm diameter (cross-sectional area: 0.086 mm ² ) circular shape (5) -2 columnar hollow portion for gas Hg: cylindrical shape with 0.33 mm diameter (5) -3 Nozzle outer diameter: 0.64 mm
(5) -4 Position:
The gas discharge portion Eg is arranged so that the outer wall surface of the nozzle abuts 2 mm upstream from both the first liquid discharge portion El ₁ and the second liquid discharge portion El ₂ (6) -1 First liquid virtual columnar portion Distance between Hvl ₁ and gas virtual columnar part Hvg:
0.31mm
(6) -2 first liquid ejection direction central axis Al ₁ and the gas discharge direction central axis Ag: when cut along a plane perpendicular to the central axis Ag of columnar hollow Hg Parallel (6) -3 gas, gas the number of use columnar hollow Hg of the cut surface of the outer periphery and the distance is the shortest straight line L1 between the outer periphery of the first liquid for the cut surface of the columnar hollow Hl _1: 1 present (7) -1 second liquid virtual columnar portion Hvl ₂ and the gas virtual columnar part Hvg:
0.31mm
(7) -2 second liquid ejection direction center axis Al ₂ gas discharging direction center axis Ag: when cut along a plane perpendicular to the central axis Ag of columnar hollow Hg Parallel (7) -3 gas, gas use columnar hollow number distance of the shortest straight line L2 between the outer circumference of the cutting surface peripheral to the cutting surface of the columnar hollow Hl ₂ for the second solution of Hg: 1 present (8) -1 collecting body:
The collection surface of the net (mesh type conveyor net whose surface is coated with a fluororesin) is arranged perpendicular to the central axis in the discharge direction of each spinning solution. (8) -2 The first liquid discharge part El ₁ of the collection body and the distance between the second liquid ejection unit El _2:
150mm
(9) Suction device:
Suction box (Suction diameter: 50mm x 230mm)
(10) Spinning container:
Acrylic container with a volume of 1 m ³ (10) -1 Gas supply device: Precision air generator (Apiste Co., Ltd., 1400-HDR)
(10) -2 Exhaust device: Fan connected to suction box (suction device)

(Manufacture of non-woven fabric)
The fibers were collected on a collector (net) under the following conditions to produce a nonwoven fabric. As a result, a nonwoven fabric excellent in texture could be produced with high productivity without scattering the fibers. The nonwoven fabric was in a state where fibers with an average fiber diameter of 0.2 μm and fibers with an average fiber diameter of 0.4 μm were uniformly mixed.
(B) discharging from the first liquid discharge nozzle Nl _1: spinning liquid A discharge at 3 g / Time (b) discharging from the second discharge nozzle Nl _2: a spinning liquid B discharged at 3 g / Time (c) air Discharge flow rate: 250 m / sec.
(D) Air discharge rate: 1.3 L / min.
(E) Net moving speed: 30 cm / min.
(F) Suction box suction conditions:
Maximum air flow 18m ³ / min. (0.1kW)
(G) Gas supply conditions:
Supplying air at a temperature of 23 ° C. and a humidity of 50% at a flow rate of 200 L / min (h) Gas exhaust conditions: 201.3 L / min. more than

(Example 2)
(Preparation of spinning solution)
A spinning solution C (viscosity (temperature: 23 ° C.): 500 mPa · s) in which polyacrylonitrile (manufactured by Aldrich) was dissolved in N, N-dimethylformamide at a concentration of 8 mass% was prepared.

  Also prepared is a spinning solution D (viscosity (temperature: 23 ° C.): 680 mPa · s) in which a polyvinylidene fluoride copolymer (manufactured by Arkema) is dissolved in N, N-dimethylformamide so as to have a concentration of 20 mass%. did.

(Preparation of non-woven fabric production equipment)
Same as Example 1

(Manufacture of non-woven fabric)
The fibers were collected on a collector (net) under the following conditions to produce a nonwoven fabric. As a result, a nonwoven fabric excellent in texture could be produced with high productivity without scattering the fibers. The nonwoven fabric was in a state where acrylic fibers having an average fiber diameter of 0.2 μm and polyvinylidene fluoride fibers having an average fiber diameter of 0.2 μm were uniformly mixed.
(B) discharging from the first liquid discharge nozzle Nl _1: spinning liquid C discharged at 3 g / Time (b) discharging from the second discharge nozzle Nl _2: a spinning liquid D discharge at 3 g / Time (c) air Discharge flow rate: 250 m / sec.
(D) Air discharge rate: 1.3 L / min.
(E) Net moving speed: 30 cm / min.
(F) Suction box suction conditions:
Maximum air flow 18m ³ / min. (0.1kW)
(G) Gas supply conditions:
Supplying air at a temperature of 23 ° C. and a humidity of 50% at a flow rate of 200 L / min (h) Gas exhaust conditions: 201.3 L / min. more than

(Example 3)
(Preparation of spinning solution)
A spinning solution E (viscosity (temperature: 23 ° C.): 500 mPa · s) prepared by dissolving polyacrylonitrile (manufactured by Aldrich) in N, N-dimethylformamide so as to have a concentration of 8 mass% was prepared.

  Further, a spinning solution F (viscosity (temperature: 23 ° C.): 1800 mPa · s) in which polyacrylonitrile (manufactured by Aldrich) was dissolved in dimethyl sulfoxide to a concentration of 8 mass% was prepared.

(Preparation of non-woven fabric production equipment)
Same as Example 1

(Manufacture of non-woven fabric)
The fibers were collected on a collector (net) under the following conditions to produce a nonwoven fabric. As a result, a nonwoven fabric excellent in texture could be produced with high productivity without scattering the fibers. The nonwoven fabric was in a state where acrylic fibers having an average fiber diameter of 0.2 μm and acrylic fibers having an average fiber diameter of 0.4 μm were uniformly mixed.
(A) Discharge from the first liquid discharge nozzle Nl ₁ : discharge the spinning liquid E at 3 g / hour (b) Discharge from the second liquid discharge nozzle Nl ₂ : discharge the spinning liquid F at 3 g / hour (c) Air Discharge flow rate: 250 m / sec.
(D) Air discharge rate: 1.3 L / min.
(E) Net moving speed: 30 cm / min.
(F) Suction box suction conditions:
Maximum air flow 18m ³ / min. (0.1kW)
(G) Gas supply conditions:
Supplying air at a temperature of 23 ° C. and a humidity of 50% at a flow rate of 200 L / min (h) Gas exhaust conditions: 201.3 L / min. more than

(Comparative Example 1)
(Preparation of spinning solution)
The same spinning solution A as in Example 1 was prepared.

(Preparation of non-woven fabric production equipment)
A manufacturing apparatus having the following configuration was prepared.
(1) Spinning liquid storage part: Stainless steel tank (2) Air supply device: Compressor (3) Liquid discharge nozzle: metal (3) -1 Liquid discharge part: 0.7 mm diameter (cross-sectional area: 0.38 mm ² ) (3) -2 Liquid columnar hollow part: 0.7 mm diameter cylindrical shape (3) -3 Nozzle outer diameter: 1.1 mm
(3) -4 Number of nozzles: 1 (4) Gas discharge nozzle: Metal (4) -1 Gas discharge part: 2.1 mm diameter (cross-sectional area: 3.46 mm ² ) circular shape (4) -2 For gas Columnar hollow: 2.1 mm diameter cylindrical shape (4) -3 Nozzle outer diameter: 2.5 mm
(4) -4 Number of nozzles: 1 (4) -5 Position:
The gas discharge part is arranged concentrically with the liquid discharge nozzle at a position 2 mm upstream of the liquid discharge part. As a result, the gas discharge part has a hollow circular shape with an inner diameter of 1.1 mm and an outer diameter of 2.1 mm (see FIG. 5)
(5) -1 Distance between liquid virtual columnar part and gas virtual columnar part: 0.2 mm
(5) -2 Liquid discharge direction central axis and gas discharge direction central axis: coincidence (5) -3 The cut surface of the gas columnar hollow when cut along a plane perpendicular to the center axis of the gas columnar hollow The number of straight lines with the shortest distance between the inner periphery of the liquid and the outer periphery of the cut surface of the columnar hollow portion for liquid: innumerable (6) -1 collector:
The collection surface of the net (mesh type conveyor net whose surface is coated with a fluororesin) is arranged perpendicular to the central axis of the spinning liquid discharge direction (6) -2 Distance from the liquid discharge part of the collection body: 300 mm
(7) Suction device:
Suction box (Suction diameter: 50mm x 230mm)
(8) Spinning container: acrylic container with a volume of 1 m ³ (8) -1 Gas supply device: precision air generator (manufactured by Apiste Co., Ltd., 1400-HDR)
(8) -2 Exhaust device: Fan connected to a suction box (suction device)

(Manufacture of non-woven fabric)
An attempt was made to produce a nonwoven fabric by spinning under the following conditions, but the fiber shape and nonwoven fabric could not be produced.
(A) Discharge amount from the liquid discharge nozzle: 3 g / hour (b) Gas discharge flow rate: 200 m / sec.
(C) Air discharge amount: 1.0 L / min.
(D) Net moving speed: 30 cm / min.
(E) Suction box suction conditions:
Maximum air flow 18m ³ / min. (0.1kW)
(F) Gas supply conditions:
Supplying air at a temperature of 23 ° C. and a humidity of 50% at a flow rate of 200 L / min (g) Gas exhaust conditions: 201 L / min. more than

(Comparative Example 2)
(Preparation of spinning solution)
The same spinning solution A and spinning solution B as in Example 1 were prepared.

(Preparation of spinning device)
A spinning device having the following configuration was prepared.
(1) Spinning liquid storage part: Syringe (2) Air supply device: Compressor (3) Liquid discharge nozzle: Metal (3) -1 Liquid discharge part: 0.33 mm diameter (cross-sectional area: 0.085 mm ² ) Circular (3) -2 Columnar hollow for liquid: Column shape with a diameter of 0.33 mm (3) -3 Nozzle outer diameter: 0.64 mm
(3) -4 Number of nozzles: 1 (4) Gas discharge nozzle: metal (4) -1 Gas discharge part: 0.33 mm diameter (cross-sectional area: 0.085 mm ² ) circle (4) -2 For gas Columnar hollow: cylindrical shape with a diameter of 0.33 mm (4) -3 Nozzle outer diameter: 0.64 mm
(4) -4 Number of nozzles: 1 (5) -1 Position:
The gas discharge part is arranged 2 mm upstream of the liquid discharge part so that the outer wall surface of the nozzle contacts (6) Distance between the liquid virtual columnar part and the gas virtual columnar part: 0.31 mm
(7) Liquid discharge direction central axis and gas discharge direction central axis: parallel (8) When cut along a plane perpendicular to the central axis of the gas columnar hollow part, the outer periphery of the cut surface of the gas columnar hollow part and the liquid Number of straight lines L1 having the shortest distance from the outer periphery of the cut surface of the columnar hollow portion for use: 1

(Preparation of non-woven fabric production equipment)
Two sets of spinning devices were prepared and arranged as follows.
(I) Collected body:
The collection surface of the net (mesh type conveyor net whose surface is coated with a fluororesin) is arranged perpendicular to the central axis of the spinning liquid discharge direction (ii) Distance between the collection surface of the collection body and the liquid discharge part: 200mm
(Iii) Suction device:
Suction box (Suction diameter: 50mm x 230mm)
(Iv) Spinning container:
Acrylic container (iv) -1 with a volume of 1 m ³ Gas supply device:
Precision air generator (Apiste Co., Ltd., 1400-HDR)
(Iv) -2 Exhaust device: Fan connected to a suction box (suction device)

(Manufacture of non-woven fabric)
Fibers were accumulated on the collector (net) under the following conditions to produce a nonwoven fabric. However, the amount of scattered fibers was greater than in Example 1, and the nonwoven fabric could not be produced stably.
(A) Discharge amount from each liquid discharge nozzle: 3 g / hour (b) Gas discharge flow rate: 200 m / sec.
(C) Air discharge amount: 1.0 L / min.
(D) Net moving speed: 30 cm / min.
(E) Suction box suction conditions:
Maximum air flow 18m ³ / min. (0.1kW)
(F) Gas supply conditions:
Supplying air at a temperature of 23 ° C. and a humidity of 50% at a flow rate of 200 L / min (g) Gas exhaust conditions: 201 L / min. more than

The perspective view which expanded the tip part of the spinning device Cross section of a conventional spinning device (A) An example of a plan view cut along a plane perpendicular to the central axis of the columnar hollow for gas (cut plane view of plane C in FIG. 1) (b) The central axis of the columnar hollow for gas (C) Other example of cutting plan view when cut along a plane perpendicular to the central axis of the columnar hollow portion for gas (d) For gas Other examples of cutting plan view when cut along a plane perpendicular to the central axis of the columnar hollow part (d) Other than the cutting plan view when cut along a plane perpendicular to the central axis of the gas columnar hollow part Example (e) Another example of a cut plan view when cut along a plane perpendicular to the central axis of the columnar hollow for gas (A) An example of a cut plan view when cutting along a plane perpendicular to the central axis of the gas columnar hollow part (b) Cutting when cutting along a plane perpendicular to the central axis of the gas columnar hollow part Other examples of plan views (c) Other examples of cut plan views when cut along a plane perpendicular to the central axis of the columnar hollow for gas Cutting plan view when cutting in a plane perpendicular to the central axis of the gas columnar hollow portion in Comparative Example 1

Explanation of symbols

Nl ₁ first liquid discharge nozzle Nl ₂ second liquid discharge nozzle Nl liquid discharge nozzle Nl _n liquid discharge nozzle Ng gas discharge nozzle El ₁ first liquid discharge part El ₂ second liquid discharge part Eg gas discharge part Hl ₁ first liquid Column-shaped hollow portion Hl ₂ Column-shaped hollow portion for second liquid Hg Gas column-shaped hollow portion Hv ₁ First liquid virtual column-shaped portion Hvl ₂ Second liquid virtual column-shaped portion Hvg Gas virtual column-shaped portion Al ₁ First discharge direction central axis (liquid )
Al ₂ 2nd discharge direction central axis (liquid)
Ag discharge direction central axis (gas)
C Vertical plane perpendicular to the central axis of the gas columnar hollow portion L1 straight line L2 straight line 12 first member 22 second member 32 third member 14, 24, 34 supply end portion 16, 26, 36 opposed outlet end portion 18 first 1 Supply slit 38 First gas slit 20 Gas jet space

Claims (4)

A spinning device satisfying the following conditions, having two or more liquid discharge portions capable of discharging a spinning solution and one gas discharge portion positioned upstream of any of the liquid discharge portions and capable of discharging gas A method for producing a nonwoven fabric, characterized in that a spinning solution is discharged from the liquid discharge section under two or more discharge conditions to be fiberized and accumulated on a collector.
(1) It has a liquid columnar hollow portion with each liquid discharge portion as an end portion (2) It has a gas columnar hollow portion with an end portion as a gas discharge portion (3) Each of the liquid columnar hollow portions extended The liquid virtual columnar part and the gas virtual columnar part obtained by extending the gas columnar hollow part are close to each other. (4) The discharge column central axis of the liquid columnar hollow part and the discharge direction central axis of the gas columnar hollow part Are parallel to each other. (5) When cut along a plane perpendicular to the central axis of the gas columnar hollow part, the outer periphery of the cut surface of the gas columnar hollow part and the outer periphery of the cut surface of the liquid columnar hollow part Only one straight line with the shortest distance can be drawn in any combination The method for producing a nonwoven fabric according to claim 1, wherein spinning liquids having different concentrations are discharged. The method for producing a nonwoven fabric according to claim 1, wherein spinning solutions of different polymers are discharged. The method for producing a nonwoven fabric according to claim 1, wherein spinning solutions of different solvents are discharged.

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