JP5417276B2 - Nanofiber manufacturing apparatus and nanofiber manufacturing method - Google Patents

Description

  The present invention relates to a nanofiber manufacturing apparatus and a nanofiber manufacturing method for manufacturing a fiber (nanofiber) having a fineness of submicron order or nano order by electrostatic stretching phenomenon.

  As a method for producing a filamentous (fibrous) material made of a resin and having a submicron scale or nanoscale diameter, a method using an electrostatic stretching phenomenon (electrospinning) is known.

  This electrostatic stretching phenomenon means that a raw material liquid in which a solute such as a resin is dispersed or dissolved in a solvent is discharged (injected) into the space by a nozzle or the like, and an electric charge is applied to the raw material liquid to charge the space. This is a method of obtaining nanofibers by electrically stretching a raw material liquid in flight.

  The electrostatic stretching phenomenon will be described more specifically as follows. That is, the raw material liquid that has been charged and discharged into the space gradually evaporates the solvent while flying through the space. As a result, the volume of the raw material liquid in flight gradually decreases, but the charge imparted to the raw material liquid remains in the raw material liquid. As a result, the charge density of the raw material liquid in flight through the space gradually increases. Since the solvent continues to evaporate, the charge density of the raw material liquid further increases, and when the repulsive Coulomb force generated in the raw material liquid exceeds the surface tension of the raw material liquid, the raw material liquid explodes. The phenomenon that the film is stretched linearly occurs. This is the electrostatic stretching phenomenon. This electrostatic stretching phenomenon occurs geometrically in succession in the space, so that nanofibers made of a resin having a diameter of sub-micron order to nano order are manufactured.

  When producing nanofibers using the electrostatic stretching phenomenon as described above, the concentration of the evaporated solvent becomes a problem. That is, if the concentration of the solvent in the space in which the raw material liquid flies is high, the solvent is difficult to evaporate from the raw material liquid, and the quality of the manufactured nanofibers is affected.

  Therefore, for example, an apparatus described in Patent Document 1 includes a deposition target member that deposits and collects nanofibers. By sucking gas from the side of the deposition target member on which nanofibers are not deposited, the nanofibers are deposited. It is a device that sucks and exhausts the evaporated solvent while attracting to the deposition member.

  The apparatus described in Patent Document 2 is an apparatus that evaporates the raw material liquid in the chamber and exhausts the atmosphere in the chamber by providing an exhaust device in the chamber.

  According to these apparatuses, it is possible to forcibly exhaust the solvent vapor in the space where the raw material liquid evaporates, and to keep the solvent concentration low.

JP 2008-223179 A JP 2008-190055 A

  However, the apparatus of Patent Document 1 sucks and exhausts the evaporated solvent through the member to be deposited and the deposited nanofibers, so that the solvent vapor can be efficiently removed from the flight path of the raw material liquid having the highest solvent concentration. Can not.

  Further, in the apparatus of Patent Document 2, the atmosphere in the chamber is sucked by the suction device attached to the wall surface of the chamber, and the outside air is sucked from the suction port provided on the wall surface of the chamber. It is conceivable that the solvent vapor cannot be quickly removed from the flight path of the raw material liquid, and a turbulent flow is generated, so that the gas flow adversely affects the quality of the manufactured nanofiber.

  The present invention has been made in view of the above problems, and efficiently discharges the solvent vapor from the flight path of the raw material liquid and can maintain the quality of the manufactured nanofiber in a high state, And it aims at provision of the nanofiber manufacturing method.

  In order to achieve the above object, a nanofiber manufacturing apparatus according to the present invention is a nanofiber manufacturing apparatus that manufactures nanofibers by electrically stretching a raw material liquid in a space. An outflow body having a plurality of outflow holes that flow out in one direction, a charging means for charging the raw material liquid flowing out from the outflow body, and a raw material liquid in the same direction as the outflow direction, in which the raw material liquid flows out from the outflow body And an air blowing means for generating a gas flow flowing along.

  According to this, since the gas flow flows along the flow of the raw material liquid, solvent vapor is discharged from the flying space where the raw material liquid and nanofibers fly without affecting the raw material liquid and nanofibers flying in the space. It becomes possible to do.

  Moreover, it is preferable that the said ventilation means is provided with the ventilation port which discharges a gas flow, and the said ventilation port is upstream from the opening part of the said outflow hole in the said outflow direction.

  According to this, the solvent evaporated from the raw material liquid immediately after flowing out from the outflow body can be efficiently discharged from the flight space. Further, since the gas flow flows along the flow of the raw material liquid in the vicinity of the opening of the outflow hole, it is possible to break or deform the tailor cone formed by the raw material liquid in the opening as much as possible. Can be suppressed.

  Moreover, the said ventilation means may be provided with the ventilation port which discharges a gas flow, and the said ventilation port may exist between the said outflow holes.

  According to this, it becomes possible to discharge | emit the solvent evaporated from the raw material liquid which flows into the both sides of a gas flow by the gas flow discharged from one ventilation port. Therefore, even when the density of the raw material liquid flying in the space is high, the solvent vapor can be efficiently discharged from the flying space.

  Furthermore, a crossing means for crossing the gas flow discharged by the blowing means may be provided for the raw material liquid flying in the space or the nanofiber manufactured from the raw material liquid and flying in the space.

  According to this, the flight path of the raw material liquid and nanofiber can be bent by crossing the gas flow with the raw material liquid in flight and the nanofiber in flight. The flight path of the fiber can be lengthened. Therefore, it is possible to increase the evaporation time of the solvent, and it is possible to manufacture high quality nanofibers.

  In order to achieve the above object, a nanofiber manufacturing method according to the present invention is a nanofiber manufacturing method for manufacturing a nanofiber by electrically stretching a raw material liquid in a space, and a plurality of outflow holes. An outflow step for causing the raw material liquid to flow out in one direction into the space from the outflow body, a charging step for charging the raw material liquid flowing out from the outflow body by a charging means, and a direction in which the raw material liquid flows out from the outflow body. And a blowing step of generating a gas flow flowing along the raw material liquid in the same direction as the outflow direction by the blowing means.

  According to this, since the gas flow flows along the flow of the raw material liquid, solvent vapor is discharged from the flying space where the raw material liquid and nanofibers fly without affecting the raw material liquid and nanofibers flying in the space. It becomes possible to do.

  According to the present invention, it is possible to improve the quality of manufactured nanofibers.

FIG. 1 is a perspective view showing a nanofiber manufacturing apparatus. FIG. 2 is a perspective view showing a cutout of the outflow body. FIG. 3 is a perspective view showing a state in which the raw material liquid is flowing out from the outflow body from the front end side of the outflow body. FIG. 4 is a side view showing the nanofiber manufacturing apparatus along with the gas flow from the Y-axis direction. FIG. 5 is a side view showing another embodiment of the nanofiber manufacturing apparatus from the Y-axis direction. FIG. 6 is a side view showing another embodiment of the nanofiber manufacturing apparatus from the Y-axis direction. FIG. 7 is a side view showing another embodiment of the nanofiber manufacturing apparatus from the Y-axis direction. FIG. 8 is a perspective view showing another embodiment of the nanofiber manufacturing apparatus.

  Next, a nanofiber manufacturing apparatus and a nanofiber manufacturing method according to the present invention will be described with reference to the drawings.

  FIG. 1 is a perspective view showing a nanofiber manufacturing apparatus.

  As shown in the figure, the nanofiber production apparatus 100 is an apparatus for producing a nanofiber 301 by electrically stretching a raw material liquid 300 in a space, and includes an effluent body 101, a charging means 102, and a blower. Means 103. Furthermore, the nanofiber manufacturing apparatus 100 includes a crossing means 104, a collecting means 105, and a supplying means 106.

  FIG. 2 is a perspective view showing a cutout of the outflow body.

  The outflow body 101 is a member for allowing the raw material liquid 300 to flow out into the space by the pressure of the raw material liquid 300 (which may include gravity), and includes an outflow hole 118. In the case of the present embodiment, the outflow body 101 further includes a front end portion 116, a side surface portion 117, and a storage tank 113. In addition, the outflow body 101 also functions as an electrode for supplying electric charge to the raw material liquid 300 that flows out, and at least a part of the portion in contact with the raw material liquid 300 is formed of a conductive member. In the case of the present embodiment, the entire outflow body 101 is made of metal. In addition, if the kind of metal is provided with electroconductivity, it will not specifically limit, Arbitrary materials, such as brass and stainless steel, can be selected.

  The outflow holes 118 are holes for allowing the raw material liquid 300 to flow out into the space in one direction (downward in the Z-axis direction in FIG. 1), and a plurality of outflow holes 118 are provided side by side with the outflow body 101. In the case of the present embodiment, the outflow holes 118 are arranged in a straight line in the Y-axis direction so as to be parallel to each other, and the openings 119 at the tips of the outflow holes 118 are arranged in a line at a predetermined interval. They are arranged side by side.

  The hole length and hole diameter of the outflow hole 118 are not particularly limited, and a shape suitable for the viscosity of the raw material liquid 300 may be selected. Specifically, the hole length is preferably selected from a range of 1 mm or more and 5 mm or less. The hole diameter is preferably selected from a range of 0.1 mm or more and 2 mm or less. Further, the shape of the outflow hole 118 is not limited to a cylindrical shape, and an arbitrary shape can be selected. In particular, the shape of the opening 119 is not limited to a circular shape, and may be a polygonal shape such as a triangle or a quadrangle, or a shape having a protruding portion such as a star shape.

  Further, the intervals at which the openings 119 are arranged may be equally spaced, and the interval between the openings 119 at the end of the effluent 101 is wider than the interval between the openings 119 at the center of the effluent 101. Alternatively, it can be arbitrarily determined such as narrowing. In the knowledge currently obtained, when the hole diameter of the opening part 119 is 0.3 mm, as for the pitch of the opening part 119, 2.5 mm or more is preferable. This is because, when the length is less than 2.5 mm, the possibility that the raw material liquids that flow out adjacently merge with each other increases. It should be noted that these hole diameters and pitches may vary depending on other conditions such as the viscosity of the raw material liquid 300.

  Further, the openings 119 need not only be arranged on the same straight line, but may be arranged in a line. Here, the term “one row” refers to a state in which, when a marginal region where all the openings 119 are arranged is surrounded by a rectangle, the openings 119 are not aligned in the width direction (X-axis direction) of the rectangle. The rectangular region where the opening 119 is disposed has a band shape. In this sense, the opening 119 may be arranged in a zigzag manner, or may be arranged so as to draw a wave such as a sine curve. Further, the above contents do not prevent the outflow holes 118 from being arranged in a matrix in the present invention.

  The front end portion 116 is a portion of the outflow body 101 where the opening 119 of the outflow hole 118 is disposed, and is a portion that connects the openings 119 disposed at a predetermined interval with a smooth surface. In the case of the present embodiment, the distal end portion 116 has an elongated rectangular plane on the surface, and the width thereof is set to be wider than the diameter of the corresponding opening 119.

  FIG. 3 is a perspective view showing a state in which the raw material liquid is flowing out from the outflow body from the front end side of the outflow body.

  As shown in the figure, the liquid pool 303 (around the opening 119 is formed by the presence of the tip 116 having a smooth surface (a flat surface in the case of the present embodiment) over the entire periphery of the opening 119. A so-called tailor cone is generated. The liquid pool 303 is considered to be generated due to the viscosity of the raw material liquid 300 and has a conical shape with a circular bottom surface larger than the opening 119. The liquid reservoir 303 adheres to the tip end portion 116 of the outflow body 101 so as to cover the opening 119. Then, the raw material liquid 300 flows out from the conical liquid pool 303 into the space. Thereby, since the opening part 119 does not contact air directly, it becomes possible to suppress the ionic wind generated from the opening part 119.

  As described above, since the tip end portion 116 connects a plurality of openings 119 with a smooth surface, it is possible to suppress electric field interference that occurs when a plurality of nozzles are arranged. In addition, ion wind generated in a region between the opening 119 and the opening 119 can be suppressed. Therefore, even if the openings 119 are arranged in a narrowed state, the nanofibers 301 can be manufactured satisfactorily, and therefore the production amount of the nanofibers 301 per unit time and unit area can be improved. Become.

  In addition, since the liquid reservoir 303 can be held in a good state by the distal end portion 116, it is considered that the generation of ion wind can be suppressed and the quality of the nanofiber 301 can be improved and the production efficiency can be improved.

  In FIG. 2, the side surface portion 117 is two surfaces that are arranged so as to sandwich the outflow hole 118, and is a portion of the outflow body 101 that extends from the distal end portion 116 and is arranged in an upright state. Further, the side surface portion 117 is provided in a state extending in the arrangement direction (Y-axis direction) of the outflow holes 118 arranged side by side, and is provided so that all the outflow holes 118 are sandwiched between the two side surface portions 117. It has been. Further, as shown in FIG. 2, the side surface portions 117 are arranged such that the distance between the side surface portions 117 increases as the distance from the front end portion 116 increases.

  The outflow body 101 includes the side surface portion 117 to suppress the generation of ionic wind, and even when the ionic wind is generated, the ionic wind can be blown in a direction that does not intersect the raw material liquid 300 flowing into the space. Therefore, the nanofiber 301 can be manufactured in a stable state without being affected by the ion wind.

  Further, since the side surface portion 117 is arranged so as to become gradually narrower toward the front end portion 116, charges can be easily concentrated on the front end portion 116, and the charge can be efficiently supplied to the raw material liquid 300.

  Furthermore, since the space around the opening 119 can be widely opened, it is considered that the solvent vapor can be efficiently discharged by the gas flow generated by the air blowing means 103 to the side of the side surface portion 117.

  As shown in FIG. 2, the storage tank 113 is a tank that is formed inside the outflow body 101 and stores the raw material liquid 300 supplied from the supply means 106 (see FIG. 1). The storage tank 113 is connected to the plurality of outflow holes 118 and supplies the raw material liquid 300 to the outflow holes 118 at the same time. In the case of the present embodiment, one storage tank 113 is provided in the outflow body 101, is widely provided from one end portion to the other end portion of the outflow body 101, and is connected to all outflow holes 118.

  As described above, the storage tank 113 has a function of temporarily storing the raw material liquid 300 in the vicinity of the outflow holes 118 and supplying the raw material liquid 300 to the plurality of outflow holes 118 with an equal pressure. The raw material liquid 300 can be allowed to flow out from each outflow hole 118 in an even state. Therefore, it is possible to suppress spatial unevenness in the quality of the manufactured nanofiber 301.

  In the present embodiment, the effluent body 101 has been described as including the thin and long tip portion 116 and the side surface portion 117 arranged so as to gradually spread from the tip portion. It is not limited. For example, a configuration in which the outflow holes 118 are provided on the peripheral wall of a circular pipe, or a configuration in which the outflow holes 118 are arranged in a matrix on the bottom surface of the rectangular box-shaped outflow body 101 can be exemplified. Moreover, the outflow body 101 provided with one outflow hole 118, for example, an outflow body such as a needle-shaped nozzle, or the outflow body 101 that is turned upside down by arranging a plurality of needle-shaped nozzles may be used.

  As shown in FIG. 1, the supply means 106 is a device that supplies the raw material liquid 300 to the effluent body 101, a tank that stores a large amount of the raw material liquid 300, a pump that pumps the raw material liquid 300 from the tank, A pipe for guiding the raw material liquid 300 to be processed is provided.

  The charging unit 102 is a device that charges the raw material liquid 300 flowing out from the effluent body 101 by applying an electric charge. In the case of the present embodiment, the charging unit 102 includes a charging electrode 121 and a charging power source 122. The outflow body 101 also functions as an element constituting the charging means 102.

  The charging electrode 121 is disposed at a predetermined distance from the effluent body 101 and has a conductivity for inducing electric charge to the effluent body 101 when the charging electrode 121 is at a higher voltage or lower voltage than the effluent body 101. It is. In the case of the present embodiment, the charging electrode 121 also functions as an attracting unit 107 that attracts the nanofiber 301 to the collecting unit 105. The charging electrode 121 is disposed at a position facing the front end portion 116 of the outflow body 101, and is grounded via a charging power source 122. On the other hand, the outflow body 101 is grounded. Therefore, when a positive voltage is applied to the charging electrode 121, a negative charge is induced in the outflow body 101, and the raw material liquid 300 is negatively charged. On the other hand, when a negative voltage is applied to the charging electrode 121, a positive charge is induced in the outflow body 101, and the raw material liquid 300 is positively charged.

  The charging power source 122 is a power source that can apply a high voltage between the effluent body 101 and the charging electrode 121 to charge the raw material liquid 300 to a desired charge density. In general, the charging power source 122 is preferably a DC power source, but does not hinder the use of the AC power source.

  The charging power source 122 may be connected to the outflow body 101 so that the outflow body 101 has a high voltage or a low voltage with respect to the charging electrode 121. Further, the charging electrode 121 and the outflow body 101 may be connected so as not to be grounded, and both electrodes of the charging power source 122 may be connected to the charging electrode 121 and the outflow body 101, respectively.

  The collecting means 105 is a device that collects the nanofibers 301 manufactured by the electrostatic stretching phenomenon. In the case of the present embodiment, the collecting unit 105 includes a member 151 to be deposited and a transport unit 152 that can transport the member 151 to be deposited.

  The member 151 to be deposited is a member that accumulates and collects nanofibers 301 flying in the space on the surface. In the case of the present embodiment, the deposition target 151 is a thin strip-like long member, and is supplied in a state of being wound around a roll 153. The member 151 to be deposited is a member for producing a non-woven fabric from the deposited nanofibers 301 and is subjected to a surface treatment so as to be easily separated from the nanofibers 301 deposited on the surface.

  The transfer means 152 is a device that relatively moves the outflow body 101 and the collection means 105. In the case of the present embodiment, the outflow body 101 is fixed, and only the deposition target member 151 is transferred to the outflow body 101. In the case of the present embodiment, the transfer means 152 pulls out the long collecting means 105 from the roll 153 and transfers the member 151 to be deposited together with the nanofibers 301 to be deposited.

  The transfer means 152 may not only move the member 151 to be deposited but also move the effluent 101 with respect to the collecting means 105. Further, the transfer means 152 may be one that transfers the member 151 to be deposited in a certain direction, and reciprocates the outflow body 101 in a direction that intersects the transfer direction of the member 151 to be deposited. In addition, the collecting means 105 is moved in a direction orthogonal to the direction in which the openings 119 are arranged, but the present invention is not limited to this, and the deposition member 151 is moved in the direction in which the openings 119 are arranged to open the outflow body 101. You may make it reciprocate in the direction orthogonal to the arrangement direction of the part 119.

  The air blowing means 103 is a device that generates a gas flow that flows along the flow of the raw material liquid 300 in the same direction as the outflow direction (Z-axis direction), which is the direction in which the raw material liquid 300 flows out from the outflow body 101. In the case of the present embodiment, as shown in FIG. 1, the air blowing means 103 is a device that can generate a gas flow in a curtain shape over the entire Y-axis direction of the outflow body 101, and a device that generates a so-called air curtain. It is. Specifically, the air blowing means 103 discharges a gas flow generated by rotating a long sirocco fan extending in the Y-axis direction by a motor from a slit-like air blowing port 131 extending in the Y-axis direction, thereby generating a curtain-like gas. A flow is generated downward in the Z-axis direction.

  According to this, a gas flow can be forced to flow in the vicinity of the raw material liquid 300 along the flow of the raw material liquid 300, and the solvent vapor is effectively discharged from the flight space in which the raw material liquid 300 and the nanofiber 301 fly. It becomes possible to do.

  Further, the air outlet 131 of the air blowing means 103 is located upstream of the opening 119 of the outflow hole in the outflow direction. This is preferable because the solvent vapor immediately after the raw material liquid 300 flows out from the effluent 101 can be discharged.

  In addition, the gas flow flowing along the outflow direction of the raw material liquid 300 does not significantly affect the liquid pool 303 (tailor cone) of the raw material liquid 300 that appears in a drooping manner at the front end portion 116 of the outflow body 101. Since the solvent vapor in the vicinity is discharged, the quality of the manufactured nanofiber 301 can be maintained in a high state.

  In addition, the ventilation means 103 is not necessarily limited to a thing provided with a sirocco fan. For example, a plurality of axial fans may be arranged in the longitudinal direction (Y-axis direction) of the arrangement range. Further, a curtain-like gas flow may be generated by discharging air pressurized by a compressor or the like from a plurality of nozzles.

  The intersecting means 104 changes the flow direction of the gas flow discharged by the blower means 103 to intersect the raw material liquid 300 or 301 with the gas flow. In the case of the present embodiment, a suction device 141 is employed as the crossing means 104.

  FIG. 4 is a side view showing the nanofiber manufacturing apparatus along with the gas flow from the Y-axis direction.

  As shown in the figure, the suction device 141 is arranged on the side opposite to the air blowing port 131 of the air blowing means 103 with respect to the raw material liquid 300 and the nanofiber 301 flying in the space. The suction device 141 is a device that can suck the gas flow A generated in a curtain shape downward in the Z-axis direction and spread in the Y-axis direction by the air blowing means 103 spreading in the entire Y-axis direction. Specifically, the suction device 141 sucks the gas flow A from a slit-like inlet 142 extending in the Y-axis direction by rotating a long sirocco fan extending in the Y-axis direction by a motor (opposite to the air blowing means 103). Then, exhaust is performed in the Y-axis direction.

  As described above, by changing the direction of the gas flow A by the suction device 141 serving as the intersecting means 104 and intersecting with the raw material liquid 300 and the nanofiber 301, the flight path of the raw material liquid 300 and the nanofiber 301 is bent and lengthened. can do. Therefore, it is possible to increase the evaporation time of the solvent, and it is possible to manufacture high quality nanofibers.

  In addition, since the gas flow A, the raw material liquid 300 and the nanofibers 301 are crossed at the deposition member 151 side, that is, at a position farther from the liquid reservoir 303 than the intermediate position between the outflow body 101 and the deposition member 151, Since the flight path is changed without affecting the liquid reservoir 303, the quality of the nanofiber 301 can be maintained in a high state.

  Further, since the gas flow A is sucked without passing between the deposited nanofibers 301 by the suction device 141 which is the crossing means 104, it is possible to avoid the grain of the deposited nanofibers 301 from becoming rough. Moreover, since it can avoid that solvent vapor | steam passes between the nanofibers 301 with the gas flow A, the evaporation of the solvent from the nanofibers 301 is prevented, and problems, such as obstructing fiberization, can be avoided. . Therefore, according to the present invention, the nanofibers 301 can be deposited in a fine grained state, and the deposited nanofibers 301 are prevented from being welded to each other and the occurrence of a solidified part in a lump state is suppressed. Therefore, it is possible to manufacture a high quality nanofiber 301 deposit (nonwoven fabric).

  In addition, this invention is not limited to the said embodiment. For example, another embodiment realized by arbitrarily combining the components described in this specification and excluding some of the components may be used as an embodiment of the present invention. In addition, the present invention also includes modifications obtained by making various modifications conceivable by those skilled in the art without departing from the gist of the present invention, that is, the meanings indicated in the claims. included.

  For example, as shown in FIG. 5, the intersecting means 104 is a plate-shaped deflecting body 143 that extends in the Y-axis direction, and has a curved surface or a bent surface that can change the direction of the gas flow A. It does not matter if you have one. By causing the gas flow A to follow the curved surface of the deflecting body 143 that is such a crossing means 104, the direction of the gas flow A can be changed to cross the gas flow A with the raw material liquid 300 or the nanofiber 301. It becomes possible.

  Further, the crossing means 104 may be provided with a suction device 141 together with the deflecting body 143. Thereby, the direction of the gas flow A can be changed effectively. Further, when the nanofiber 301 is attached to the deflecting body 143, the crossing means 104 may be provided with a suction device 141 instead of the deflecting body 143.

  Further, the air outlet 131 of the air blowing means 103 does not need to be disposed on the side of the outflow body 101, and a guide plate 132 for guiding the gas flow A discharged from the air outlet 131 may be provided. The guide plate 132 has a function of preventing the flow of the gas flow A from being disturbed by another gas flow generated in the nanofiber manufacturing apparatus 100. For example, when the suction device 141 is provided, it is possible to prevent the gas flow generated by the suction force of the suction device 141 from acting on the gas flow A from above the outflow body 101 and disturbing the gas flow A. .

  Further, as shown in FIG. 6, the intersecting unit 104 may be a second blowing unit 144 similar to the blowing unit 103. The second air blowing means 144 is arranged on the same side as the air blowing port 131 of the air blowing means 103 with respect to the flight path of the raw material liquid 300 and the nanofiber 301, and the gas flow A is passed in the direction intersecting the raw material liquid 300 and the nanofiber 301. It is an apparatus for generating a second gas flow B to be bent.

  According to this, the flight path of the raw material liquid 300 and the nanofiber 301 can be bent more greatly by the gas flow A and the second gas flow B, and the flight path is lengthened while maintaining the nanofiber manufacturing apparatus 100 compact. Thus, it is possible to increase the evaporation efficiency of the solvent.

  In addition, as shown in FIG. 7, the air outlet 131 of the air blowing means 103 may be disposed between the outflow holes 118. In the figure, a plurality of outflow bodies 101 having outflow holes 118 are provided, and the air outlets 131 are arranged between the outflow bodies 101.

  According to this, even when a large number of outflow holes 118 are provided in a narrow space, the solvent vapor can be efficiently discharged by the gas flow A flowing between the outflow holes 118. Therefore, it is possible to produce high-quality nanofibers 301 with high production efficiency.

  In FIG. 7, the suction device 141 is described as the crossing means 104, but it is needless to say that the invention is included in the present invention even when the crossing means 104 is not provided. Moreover, it may replace with the suction means 141, or may provide the turning body 143 with the suction apparatus 141. FIG.

  Moreover, although two outflow bodies 101 are described in the same figure, three or more outflow bodies 101 may be arranged, and the air outlet 131 of the air blowing means 103 may be provided between the adjacent outflow bodies 101. Moreover, the outflow body 101 should just be provided with the outflow hole 118, and the number of the outflow holes 118 is arbitrary. Therefore, it is a matter of course that the present invention can be realized even if a plurality of nozzle-like outflow bodies 101 each having one outflow hole 118 are provided and the air blowing port 131 is disposed therebetween.

  Further, as shown in FIG. 8, guide means 145 for guiding the gas flow A sucked by the suction device 141 serving as the intersecting means 104 to the blowing means 103 may be provided. The guide means 145 shown in the figure is a duct that connects the exhaust port of the suction device 141 and the suction port of the blower means 103. Thus, by circulating the gas flow A using the guide means 145, it is possible to reduce the load on the motor of the air blowing means 103 and the like. Further, the suction device 141 includes only the air inlet 142 without including a motor or a fan, and sucks the gas flow A that intersects the flight path of the raw material liquid 300 and the nanofiber 301 using the suction force of the blower 103. It doesn't matter what you do.

  Next, the manufacturing method of the nanofiber 301 using the nanofiber manufacturing apparatus 100 of the said structure is demonstrated.

  Here, the resin constituting the nanofiber, which is dissolved or dispersed in the raw material liquid, includes polypropylene, polyethylene, polystyrene, polyethylene oxide, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, poly-m- Phenylene terephthalate, poly-p-phenylene isophthalate, polyvinylidene fluoride, polyvinylidene fluoride-hexafluoropropylene copolymer, polyvinyl chloride, polyvinylidene chloride-acrylate copolymer, polyacrylonitrile, polyacrylonitrile-methacrylate copolymer, Polycarbonate, polyarylate, polyester carbonate, polyamide, aramid, polyimide, polycaprolactone, polylactic acid, polyglycolic acid, collagen Polyhydroxy butyrate, polyvinyl acetate, polypeptides and the like, and polymeric materials such as copolymers thereof can be exemplified. Moreover, the kind selected from the above may be used, and a plurality of kinds may be mixed. In addition, the above is an illustration and this invention is not limited to the said resin.

  Examples of the solvent used in the raw material liquid include volatile organic solvents. Specific examples are methanol, ethanol, 1-propanol, 2-propanol, hexafluoroisopropanol, tetraethylene glycol, triethylene glycol, dibenzyl alcohol, 1,3-dioxolane, 1,4-dioxane, methyl ethyl ketone, methyl isobutyl. Ketone, methyl-n-hexyl ketone, methyl-n-propyl ketone, diisopropyl ketone, diisobutyl ketone, acetone, hexafluoroacetone, phenol, formic acid, methyl formate, ethyl formate, propyl formate, methyl benzoate, ethyl benzoate, benzoate Propyl acid, methyl acetate, ethyl acetate, propyl acetate, dimethyl phthalate, diethyl phthalate, dipropyl phthalate, methyl chloride, ethyl chloride, methylene chloride, chloroform, o-chloroto Ene, p-chlorotoluene, chloroform, carbon tetrachloride, 1,1-dichloroethane, 1,2-dichloroethane, trichloroethane, dichloropropane, dibromoethane, dibromopropane, methyl bromide, ethyl bromide, propyl bromide, acetic acid, Benzene, toluene, hexane, cyclohexane, cyclohexanone, cyclopentane, o-xylene, p-xylene, m-xylene, acetonitrile, tetrahydrofuran, N, N-dimethylformamide, N, N-dimethylacetamide, dimethylsulfoxide, pyridine, water Etc. can be listed. Moreover, the kind selected from the above may be used, and a plurality of kinds may be mixed. In addition, the above is an illustration and the raw material liquid used for this invention is not limited to employ | adopting the said solvent.

Further, an inorganic solid material may be added to the raw material liquid. Examples of the inorganic solid material include oxides, carbides, nitrides, borides, silicides, fluorides, sulfides, etc., but oxidation is performed from the viewpoint of heat resistance and workability of the manufactured nanofibers. It is preferable to use a product. Examples of the oxide include Al ₂ O ₃ , SiO ₂ , TiO ₂ , Li ₂ O, Na ₂ O, MgO, CaO, SrO, BaO, B ₂ O ₃ , P ₂ O ₅ , SnO ₂ , ZrO ₂ , K. ₂ O, Cs ₂ O, ZnO, Sb ₂ O ₃ , As ₂ O ₃ , CeO ₂ , V ₂ O ₅ , Cr ₂ O ₃ , MnO, Fe ₂ O ₃ , CoO, NiO, Y ₂ O ₃ , Lu ₂ Examples thereof include O ₃ , Yb ₂ O ₃ , HfO ₂ , Nb ₂ O _{5 and the} like. Moreover, the kind selected from the above may be used, and a plurality of kinds may be mixed. In addition, the above is an illustration and the substance added to the raw material liquid of this invention is not limited to the said additive.

  The mixing ratio of the solvent and the solute in the raw material liquid varies depending on the type of solvent selected and the type of solute, but the amount of solvent is preferably between about 60 wt% and 98 wt%. The solute is preferably 5 to 30% by weight.

  First, the raw material liquid 300 is supplied to the effluent body 101 by the supply means 106 (supply process). As described above, the raw material liquid 300 is filled in the storage tank 113 of the effluent body 101.

  Next, the charging electrode 121 is set to a positive or negative high voltage by the charging power source 122. Charge concentrates on the tip 116 of the effusing body 101 facing the charging electrode 121, and the charge passes through the outflow hole 118 and is transferred to the raw material liquid 300 flowing into the space, so that the raw material liquid 300 is charged (charging process). ).

  By performing the charging step and the supplying step at the same time, the charged raw material liquid 300 flows out from the opening 119 of the effluent body 101 (outflow step).

  Moreover, the gas flow A along the flow of the raw material liquid 300 is discharged from the blower port 131 by the blower 103 (discharge process).

  Here, the raw material liquid 300 flowing out from the opening 119 forms a liquid pool 303 that covers the opening 119 and hangs down from the front end 116. The liquid pool 303 is formed for each of the plurality of openings 119, and the raw material liquid 300 hangs down from the tip of the liquid pool 303 (see FIG. 3). By forming the liquid reservoir 303 in this way, it is possible to suppress the generation of ion wind and improve the quality of the manufactured nanofiber 301.

  Further, the gas flow A pushes out the solvent vapor including the vicinity of the liquid reservoir 303 without greatly affecting the liquid reservoir 303.

  Next, the nanofiber 301 is manufactured by an electrostatic stretching phenomenon acting on the raw material liquid 300 that has flew in the space to some extent (a nanofiber manufacturing process). Here, the raw material liquid 300 flows out in a strong charged state (high charge density) without being influenced by the ion wind, and the raw material liquid 300 flying from each opening 119 flows out in a thin state without being collected. Thereby, most of the raw material liquid 300 is changed to the nanofiber 301. In addition, since the raw material liquid 300 flows out in a strongly charged state (high charge density), electrostatic stretching occurs over many orders, and a large amount of nanofibers 301 with a small wire diameter are manufactured. Further, the gas stream A pushes and bends the flight path of the raw material liquid 300 and the nanofiber 301 while discharging the solvent vapor from the flight path, so that the flight path becomes longer, and the evaporation of the solvent is further promoted to cause the electrostatic stretching phenomenon. Prompt.

  In this state, the nanofiber 301 is attracted to the deposition member 151 by an electric field generated between the charging electrode 121 disposed behind the deposition target member 151 and the outflow body 101 (attraction process).

  As described above, the nanofiber 301 is deposited and collected on the member 151 to be deposited (collecting step). Since the member 151 to be deposited is slowly transferred by the transfer means 152, the nanofiber 301 is also collected as a long belt-like member extending in the transfer direction.

  By using the nanofiber manufacturing apparatus 100 configured as described above and performing the above nanofiber manufacturing method, it is possible to manufacture high-quality nanofibers 301 while maintaining high production efficiency.

  The present invention can be used for producing nanofibers, spinning using nanofibers, and producing nonwoven fabrics.

DESCRIPTION OF SYMBOLS 100 Nanofiber manufacturing apparatus 101 Outflow body 102 Charging means 103 Blowing means 104 Crossing means 105 Collecting means 106 Supply means 107 Attraction means 113 Reserving tank 116 Tip part 117 Side part 118 Outflow hole 119 Opening part 121 Charging electrode 122 Charging power supply 131 Blower 132 Guide plate 141 Suction device 142 Air inlet 143 Diverting body 144 Second air blowing means 145 Guide means 151 Deposited member 152 Transfer means 153 Roll 300 Raw material liquid 301 Nanofiber

Claims (6)

A nanofiber production apparatus for producing a raw material solution by electrically stretching in a space and depositing it by a collecting means for collecting nanofibers,
An outflow body provided with a plurality of outflow holes for allowing the raw material liquid to flow out into the space in one direction so as to be parallel to each other;
Charging means for charging the raw material liquid flowing out from the effluent,
A blowing means for generating a gas flow that flows along the raw material liquid in the same direction as the outflow direction in which the raw material liquid flows out from the outflow body over the entire first direction of the outflow body;
To nanofibers which flies are manufactured in space from the raw material liquid flying in space, said by intersecting gas flow discharged by the blowing means, in a state spread in a first direction, deposited by said collecting means And a long suction means for sucking without passing between the formed nanofibers. The blowing means includes a blowing port for discharging a gas flow,
2. The nanofiber manufacturing apparatus according to claim 1, wherein the air blowing port is located upstream of the opening of the outflow hole in the outflow direction. The blowing means includes a blowing port for discharging a gas flow,
The nanofiber manufacturing apparatus according to claim 1, wherein the air blowing port is located between the plurality of outflow bodies . The said suction | inhalation means is arrange | positioned on the opposite side to the said ventilation port with respect to the raw material liquid which flies in the space, or the nanofiber manufactured from the said raw material liquid and flies in the space. Nanofiber manufacturing equipment. further,
The nanofiber manufacturing apparatus according to claim 1, further comprising guide means for guiding the gas sucked by the suction means to the blower means. A nanofiber manufacturing method in which a raw material liquid is electrically stretched in a space and deposited by a collecting means for collecting nanofibers.
An outflow step of causing the raw material liquid to flow out in one direction from the outflow body provided with a plurality of outflow holes arranged in the first direction so as to be parallel to each other;
A charging step of charging the raw material liquid flowing out of the effluent by a charging means;
A blowing step of generating a gas flow that flows along the raw material liquid in the same direction as the outflow direction, which is the direction in which the raw material liquid flows out from the outflow body, over the entire first direction of the outflow body by the blowing means;
To nanofibers which flies are manufactured in space from the raw material liquid flying in space, said by intersecting gas flow discharged by the blowing means, in a state spread in a first direction, deposited by said collecting means A suction step of sucking by a long suction means without passing between the formed nanofibers.

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