JP4972027B2 - Nanofiber manufacturing equipment, non-woven fabric manufacturing equipment - Google Patents

Description

  The present invention relates to a nanofiber manufacturing apparatus that manufactures nanofibers using an electrospinning method (electrostatic explosion), and a non-woven fabric manufacturing apparatus that manufactures nonwoven fabrics by depositing nanofibers manufactured by an electrospinning method. The present invention relates to a nanofiber manufacturing apparatus and a non-woven fabric manufacturing apparatus for manufacturing nanofibers with high density and depositing them with high density.

  An electrospinning (charge-induced spinning) method is known as a method for producing a filamentous (fibrous) material (nanofiber) made of a polymer material or the like and having a submicron-scale diameter.

  In this electrospinning method, a raw material liquid in which a polymer substance or the like is dispersed or dissolved in a solvent is ejected (discharged) into the space by a nozzle or the like, and the raw material liquid is charged and charged to fly through the space. This is a method for obtaining nanofibers by electrostatically exploding the raw material liquid therein.

  More specifically, the volume of the raw material liquid decreases as the solvent evaporates from the particles of the raw material liquid in flight, but the charge imparted to the raw material liquid is maintained. The charge density of the grains increases. Since the solvent continuously evaporates, the charge density of the raw material liquid particles is further increased, and the polymer is rebounded when the repulsive Coulomb force generated in the raw material liquid grains exceeds the surface tension of the raw material liquid. A phenomenon (electrostatic explosion) in which the solution is stretched linearly occurs. This electrostatic explosion is generated in a spiral manner one after another in the space, thereby producing a nanofiber made of a polymer having a submicron diameter (for example, see Patent Document 1).

When nanofibers manufactured by the electrospinning method are used as raw materials for yarns and nonwoven fabrics, it is necessary to collect a large amount of nanofibers at high density. Therefore, for example, Patent Document 2 describes an invention in which a large number of nanofibers are manufactured at a high density by arranging a large number of nozzles for injecting a raw material liquid toward a collecting electrode that is an electrode for collecting nanofibers. Has been.
Japanese Patent Laying-Open No. 2005-330624 JP 2002-201559 A

  However, as described above, the electrospinning method generates a high voltage between the nozzle and the collecting electrode, and collects the charged nanofibers by an electric field. Therefore, simply increasing the number of nozzles for injecting the raw material liquid causes electric field interference between the nozzles, and the electric field between the nozzle and the collecting electrode is not stable, or interference occurs between nanofibers charged with the same polarity. As a result, the density of the nanofibers in the space becomes coarse and dense, making it difficult to collect the nanofibers in a stable state.

  Furthermore, since nanofibers, which are insulator materials charged to the same polarity, are deposited on the collecting electrode, it becomes difficult to collect nanofibers over a certain amount.

  The invention of the present application has been made in view of the above problems, and a nanofiber manufacturing apparatus capable of stably manufacturing a large amount of nanofibers and collecting them in a stable state, a non-woven fabric manufacturing apparatus composed of nanofibers, etc. The purpose is to provide.

  In order to achieve the above object, a nanofiber manufacturing apparatus according to the present invention comprises: an injection unit that injects a raw material liquid that is a raw material of nanofibers into a space; and a charging unit that imparts a charge to the raw material liquid and charges it. And a guide body that forms a wind tunnel for guiding the manufactured nanofiber, and a gas flow generating means for generating a gas flow for guiding the nanofiber inside the guide body.

  Thereby, it becomes possible to convey the nanofiber manufactured by electrostatic explosion to a predetermined place with the gas flow which distribute | circulates the inside of a guide body. Therefore, it is possible to collect the nanofibers uniformly without being affected by the electric field.

  Moreover, it is preferable that the said guide body is provided with the bending part which changes the guide direction of the said nanofiber.

  Thereby, it becomes possible to collect only nanofibers in a desired form and state.

  Furthermore, you may provide the static elimination means which neutralizes the manufactured nanofiber.

  According to this, nanofibers charged to the same polarity do not repel each other, and the nanofiber can be easily guided by the gas flow.

  Furthermore, it is preferable to provide a heating means for heating the gas constituting the gas flow.

  According to this, it is possible to forcibly evaporate the solvent from the injected raw material liquid, and it is possible to promote electrostatic explosion and efficiently manufacture nanofibers.

  In addition, an injection unit that injects a raw material liquid, which is a raw material of the nanofiber, into the space, a charging unit that applies an electric charge to the raw material liquid and charges, a guide body that forms a wind tunnel for guiding the manufactured nanofiber, The non-woven fabric manufacturing apparatus includes a gas flow generating means for generating a gas flow for guiding the nanofibers in the guide body, and a collector that has air permeability and collects the guided nanofibers. It is possible to enjoy the effect.

  Furthermore, a thick nonwoven fabric can be manufactured by providing a suction means for sucking the gas constituting the gas flow on the side opposite to the side on which the nanofibers are collected of the collection body.

  It is preferable that a plurality of suction means are provided, and suction control means for individually controlling the suction amount of the suction means.

  Thereby, it becomes possible to control the thickness distribution of the nanofiber deposited on the collector.

  Furthermore, it is preferable that a region restricting means for restricting the suction region of the suction means is provided on the side of the collector opposite to the side on which the nanofibers are collected.

  Thereby, it becomes possible to pass a gas flow through a collector more effectively.

  According to the present invention, since the manufactured nanofibers are conveyed by a gas flow, a large amount of manufactured nanofibers can be stably present at a high density in a predetermined space. Therefore, a large amount of nanofibers can be collected stably.

  Next, an embodiment of a nanofiber manufacturing apparatus according to the present invention and a nonwoven fabric manufacturing apparatus including the nanofiber manufacturing apparatus will be described with reference to the drawings.

(Embodiment 1)
FIG. 1 is a cross-sectional view schematically showing a nonwoven fabric production apparatus according to an embodiment of the present invention.

  As shown in the figure, the nonwoven fabric manufacturing apparatus 100 includes a nanofiber manufacturing apparatus 200, a collection body 101, a suction means 102, a region regulating means 103, a transport means 104, a suction control means 105, and a solvent recovery apparatus. 106.

  The collection body 101 is a member on which the nanofibers manufactured in the space are deposited, and is a member having air permeability in order to collect the nanofibers guided by the gas flow. In the case of the present embodiment, the collection body 101 is a thin and flexible long sheet-like member made of a material that can be easily separated from the deposited nanofibers. Specifically, as the collection body 101, a long net made of aramid fibers can be exemplified. Furthermore, it is preferable to perform a Teflon (registered trademark) coating on the surface because the peelability of the collected nanofibers is improved. Moreover, the collection body 101 is supplied from the supply roll 111 in the state wound by roll shape.

  The transporting unit 104 pulls out the long collection body 101 from the supply roll 111 and slowly moves the vicinity of the nanofiber manufacturing apparatus 200 to transport nanofibers deposited on the collection body 101. Yes. The conveyance means 104 can wind up the nonwoven fabric on which the nanofibers are deposited together with the collection body 101.

  The suction means 102 is arranged on the side opposite to the side on which the nanofibers are collected of the collection body 101, that is, on the side opposite to the side on which the nanofiber production apparatus 200 is arranged, and passes through the collection body 101 from the nanofiber production apparatus 200. It is a device that sucks the gas that constitutes the flowing gas flow. In the present embodiment, the nonwoven fabric manufacturing apparatus 100 includes a blower such as a sirocco fan or an axial fan as the suction unit 102. The suction means 102 is disposed inside the duct 121 and sucks the gas flow mixed with the evaporated solvent, and can pass through the duct 121 and be conveyed to the solvent recovery device 106. Yes.

  The suction control means 105 is an apparatus that is electrically connected to the suction means 102 and controls the suction amount of the suction means 102. In this embodiment, a blower is employed as the suction means 102, and the suction control means 105 controls the amount of gas suction by controlling the rotational speed of the blower.

  The area regulating means 103 has a function of regulating the suction area of the suction means 102, and is disposed on the opposite side of the collection body 101 from the side where the nanofibers are collected, and is disposed between the collection body 101 and the suction means 102. The both ends are open cylinders. The shape of the region restricting means 103 preferably corresponds to the end shape from which the nanofibers of the nanofiber manufacturing apparatus 200 are emitted. For example, if the end shape is rectangular, the region restricting means 103 is also a rectangular tube. The body is preferred. Further, if the end shape is cylindrical, the region regulating means 103 is also preferably cylindrical.

  The nanofiber production apparatus 200 is an apparatus for producing a nanofiber 301 by injecting a charged raw material liquid 300 into a space and generating an electrostatic explosion in the space. The injection means 201, the charging means 202, A gas flow generation unit 203, a gas flow control unit 204, a heating unit 205, a guide body 206, and a charge removal unit 207 are provided.

  In addition, although the raw material liquid for manufacturing a nanofiber is described as the raw material liquid 300, and the manufactured nanofiber is described as the nanofiber 301, the boundary between the raw material liquid 300 and the nanofiber 301 is ambiguous in manufacturing. It is not something that can be clearly distinguished.

  FIG. 2 is a cross-sectional view showing the raw material liquid discharge portion.

  FIG. 3 is a perspective view showing the raw material liquid discharge portion.

  Note that the raw material liquid discharge unit 290 is an injection unit 201, a charging unit 202, a first gas flow generation unit 231 (see below), which is one of the gas flow generation units 203, a gas flow control unit 204 (see below), A generic term for a group of members for discharging the raw material liquid 300 to the guide body 206, such as a heating means 205 (see below).

  The injection unit 201 is a device that injects the raw material liquid 300 into the space, and includes a rotating container 211, a rotating shaft 212, and a motor 213.

  The rotating container 211 is a container that can temporarily store the raw material liquid 300 and can inject the stored raw material liquid 300 into the space, has a cylindrical shape with one end closed, and has an injection port 216 on the peripheral wall. It has many. The other end portion of the rotating container 211 includes a flange portion 214 that protrudes inward. The flange portion 214 functions as a bank for storing a predetermined amount of the raw material liquid 300 inside the rotary container 211. Further, the rotating container 211 is formed of a conductor in order to give a charge to the stored raw material liquid 300.

  The rotating shaft body 212 is a shaft body for transmitting a driving force for rotating the rotating container 211 and injecting the raw material liquid 300 by centrifugal force, and is inserted into the rotating container 211 from the other end of the rotating container 211. This is a rod-like body in which the closed portion and one end portion of the rotating container 211 are joined. The other end is joined to the rotating shaft of the motor 213.

  The charging unit 202 is a device that charges the raw material liquid 300 by charging it, and includes an induction electrode 221, an induction power source 222, and a grounding unit 223.

  The induction electrode 221 is a member that induces electric charges to the rotating container 211 that is arranged in the vicinity and grounded when the induction electrode 221 has a high voltage with respect to the ground, and is arranged so as to surround the distal end portion of the rotating container 211. It is an annular member.

  The induction power supply 222 is a power supply that can apply a high voltage to the induction electrode 221. The induction power supply 222 may be direct current or alternating current.

  Specifically, the diameter of the rotating container 211 is preferably adopted from a range of 10 mm to 300 mm. If it is too large, it is difficult to concentrate the raw material liquid 300 and the nanofiber 301 by the gas flow or to stably rotate the rotating container because it is necessary to strengthen the structure supporting the rotating container. is there. On the other hand, if it is too small, the rotation for injecting the raw material liquid 300 by centrifugal force must be increased, and problems such as motor load and vibration occur. Furthermore, it is preferable to employ the diameter of the rotating container 211 from the range of 20 mm or more and 100 mm or less. Moreover, the shape of the injection port 216 is preferably circular, and the diameter is preferably employed from a range of 0.01 mm to 2 mm.

  The motor 213 is a device that applies a rotational driving force to the rotary container 211 via the rotary shaft body 212 in order to inject the raw material liquid 300 from the injection port 216 by centrifugal force. The rotational speed of the rotary container 211 is selected from a range of several rpm or more and 10,000 rpm or less depending on the diameter of the injection port 216, the viscosity of the raw material liquid 300 to be used, the type of polymer substance in the raw material liquid, and the like. Preferably, when the motor 213 and the rotating container 211 are linearly moved as in the present embodiment, the rotational speed of the motor 213 coincides with the rotational speed of the rotating container 211.

  Although the size of the induction electrode 221 needs to be larger than the diameter of the rotating container 211, it is preferable that the diameter is adopted from a range of 200 mm or more and 800 mm or less.

  The induction power supply 222 is a power supply that can apply a high voltage to the induction electrode 221. In general, the induction power supply 222 is preferably a DC power supply. In particular, a direct current power source is preferable when the charged polarity of the nanofiber 301 to be generated is not affected, or when the charged nanofiber 301 is collected and collected on the electrode. In other cases, an AC power source may be used. In addition, when the induction power supply 222 is a DC power supply, the voltage applied by the induction power supply 222 to the induction electrode 221 is preferably set from a value in the range of 10 KV or more and 200 KV or less. The induction electrode 221 only needs to be arranged so as to surround the rotating container 211 with a predetermined distance from the rotating container 211, and may be an annular metal wire that surrounds the rotating container 211.

  In particular, the electric field strength between the rotating container 211 and the induction electrode 221 is important, and it is preferable to arrange the applied voltage and the induction electrode 221 so that the electric field strength is 1 KV / cm or more.

  The grounding means 223 is a member that is electrically connected to the rotating container 211 and can maintain the rotating container 211 at the ground potential, and one end of the grounding means 223 has an electrical connection state even when the rotating container 211 is in a rotating state. It functions as a brush so that it can be maintained, and even when the rotating container 211 is rotating, it comes into stable contact with the rotating container 211 at multiple points, so The end is connected to the ground. In addition, as a method of grounding the rotating container 211, when the rotating shaft body 212 is a conductor, the rotating container 211 may be grounded by contacting the rotating shaft body similarly as a brush.

  If an induction method is employed for the charging unit 202 as in the present embodiment, it is possible to apply a charge to the raw material liquid 300 while maintaining the rotating container 211 at the ground potential. If the rotating container 211 is in the ground potential state, it is not necessary to electrically insulate members such as the rotating shaft 212 and the motor 213 connected to the rotating container 211 from the rotating container 211, and the simple structure as the ejection unit 201 is achieved. Can be adopted, which is preferable.

  As a charging means, a power source may be directly connected to the rotating container 211, and the rotating container 211 may be maintained at a high voltage to apply a charge to the raw material liquid 300. In addition, the rotary container 211 is formed of an insulator, and an electrode that directly contacts the raw material liquid 300 stored in the rotary container 211 is disposed inside the rotary container 211, and an electric charge is applied to the raw material liquid 300 using the electrode. It may be a thing.

  The first gas flow generation means 231, which is one of the gas flow generation means 203, generates a gas flow for changing the flight direction of the raw material liquid 300 injected from the rotary container 211 to the direction of the guide body 206. Device. In the case of the present embodiment, a blower including an axial fan that forcibly blows the surrounding atmosphere (air) is employed as the first gas flow generating means 231. The first gas flow generating means 231 is provided on the back of the motor 213 and generates a gas flow from the motor 213 toward the tip of the rotating container 211. The first gas flow generating means 231 can generate wind power that can be changed in the axial direction before the raw material liquid 300 injected in the radial direction from the rotating container 211 reaches the induction electrode 221 by centrifugal force. It has become.

  In FIG. 2, the gas flow is indicated by arrows.

  Further, the first gas flow generating means 231 may be constituted by another blower such as a sirocco fan.

  The gas flow control means 204 has a function of controlling the gas flow so that the gas flow generated by the gas flow generation means does not hit the injection port. In this embodiment, as the gas flow control means 204, An air passage body that guides the gas flow so as to flow in a predetermined region is employed. The gas flow control unit 204 includes an annular introduction port 241 into which the gas flow generated by the first gas flow generation unit 231 is introduced, and the gas flow does not directly hit the injection port 216 and the rotary container An outlet 242 for deriving a gas flow is provided in a region where the raw material liquid 300 injected in the radial direction from 211 can be converted into the axial direction. Further, an air passage 243 connecting the inlet 241 and the outlet 242 is provided. The inlet 241, the outlet 242 and the air passage 243 are formed by a resin air passage body.

  The gas flow control means 204 may be a wall-shaped windbreak wall that is arranged on the windward side of the injection port 216 and prevents the gas flow from reaching the vicinity of the injection port 216.

  The heating unit 205 is a heating source that heats a gas (safe gas) that constitutes a gas flow generated by the first gas flow generation unit 231. In the case of the present embodiment, the heating means 205 is an annular heater disposed in the vicinity of the inlet 241 in the air passage 243 and can heat the gas passing through the heating means 205. .

  By heating the gas flow by the heating means 205, the raw material liquid 300 injected into the space is promoted to evaporate, and nanofibers can be manufactured efficiently.

  Returning to FIG.

  The guide body 206 is a member that forms a wind tunnel that guides the raw material liquid 300 and the nanofibers 301 discharged from the raw material liquid discharge unit 290 so as to pass through a predetermined flight path. More specifically, the guide body 206 is a cylindrical member that guides the raw material liquid 300 and the nanofibers 301 by guiding the gas flow generated by the gas flow generation means 203.

  The guide body 206 includes an introduction opening 261 that can receive the raw material liquid 300 and the nanofiber 301 discharged from the raw material liquid discharge unit 290 together with the gas flow generated by the first gas flow generation unit 231 at the base end. Yes. The introduction opening 261 has a size capable of sufficiently introducing the raw material liquid 300 and the nanofiber 301 into the guide body 206. The introduction opening 261 is preferably larger than the induction electrode 221.

  The guide body 206 includes an electrostatic explosion portion 262 that follows the introduction opening portion 261. The electrostatic explosion part 262 is a part of the guide body 206 that forms a space where the raw material liquid 300 is sufficiently electrostatically exploded and the nanofiber 301 can be manufactured.

  The guide body 206 includes a static elimination unit 263 following the electrostatic explosion unit 262. The neutralization unit 263 is a portion of the guide body 206 that forms a space for neutralizing the nanofiber 301 that is manufactured by electrostatic explosion and is still charged. The neutralization unit 263 may have a length sufficient to neutralize the nanofiber 301 naturally, or may include a neutralization unit 207 that forcibly neutralizes the nanofiber 301.

  The neutralization means 207 is a device that forcibly neutralizes the charged nanofiber 301 and can discharge ions or particles having a polarity opposite to that of the charged nanofiber 301 into the space. It is. Specifically, the static elimination means 207 comprising any method such as a corona discharge method, a voltage application method, an AC method, a steady DC method, a pulse DC method, a self-discharge method, a soft X-ray method, an ultraviolet ray method, and a radiation method is adopted. Good.

  The guide body 206 includes a contraction portion 264 that follows the charge removal portion 263. The contraction part 264 is a part of the guide body 206 whose diameter (area) gradually decreases from the upstream side to the downstream side of the gas flow, and the taper shape improves the density of the nanofibers 301 existing in the space. It has. The contraction unit 264 includes gas flow inlets 233 on the upstream side and the downstream side of the gas flow, respectively. The gas flow introduction port 233 is connected to the second gas flow generation means 232 that is one of the gas flow generation means 203 and is an opening for introducing a high-speed gas flow into the guide body 206. The gas flow inlet 233 is provided in a direction in which a gas flow can be ejected from the side of the contraction portion 264 having a large diameter toward the side of a small diameter.

  The second gas flow generation means 232 is a device that generates a gas flow by introducing high-pressure gas into the guide body 206. Specifically, the second gas flow generating means 232 includes a tank (cylinder) that can store high-pressure gas, a pump that forcibly introduces gas into the tank, and a valve that adjusts the pressure of the high-pressure gas in the tank. An apparatus provided with the gas derivation means which has can be illustrated.

  The gas supplied by the second gas flow generating means 232 may be air, but is preferably a safety gas having an oxygen content ratio lower than that of air. This is to avoid explosion caused by the solvent evaporating from the raw material liquid 300. Examples of the safety gas include a low oxygen concentration gas obtained by removing oxygen from air to some extent by a resin membrane (hollow fiber membrane), and superheated steam. This description does not exclude the use of high-purity gas containing almost no oxygen, but carbon dioxide supplied from high-purity nitrogen or dry ice sealed in a cylinder in a liquid or gas state. Etc. are also available.

  Further, a heating means for heating the gas flow generated by the second gas flow generation means 232 may be provided.

  The manufactured nanofiber 301 is neutralized by the guide body 206 and the gas flow generation means 203 described above, reaches the collection body 101 in a high density state, and deposits on the collection body 101. Therefore, density density is less likely to occur in the space due to the influence of the electric field, and the nanofibers 301 can be collected in a deposited state in a stable state. In addition, since there is no high-voltage member in the vicinity of the collector 101, a device necessary for insulation measures is not necessary, and safety for human bodies such as electric shock can be improved.

  Next, an outline of a manufacturing method of the nanofiber 301 will be described.

  First, a gas flow is generated inside the raw material liquid discharge part 290 and the guide body 206 by the gas flow generation means 203. On the other hand, the gas flow is sucked from the downstream side of the collecting body 101 by the suction means 102.

  Next, the raw material liquid 300 is supplied to the rotating container 211. The raw material liquid 300 is separately stored in a tank (not shown), passes through the raw material liquid supply path 217 (see FIG. 1), and is supplied into the rotary container 211 from the other end of the rotary container 211. Next, while supplying electric charge to the raw material liquid 300 stored in the rotary container 211 by the induction power supply 222, the rotary container 211 is rotated by the motor 213, and the charged raw material liquid 300 is injected from the injection port 216 by centrifugal force. .

  Here, as the raw material liquid 300 for manufacturing the nanofiber 301, what melt | dissolves and mixes an organic solvent in an epoxy resin, a polyimide resin, a LCP (liquid crystal polymer) resin, etc. can be illustrated.

  Further, examples of other solute materials include 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, nylon, aramid, polycaprolactone, Examples thereof include polylactic acid, polyglycolic acid, collagen, polyhydroxybutyric acid, polyvinyl acetate, and polypeptide. Moreover, the above-mentioned one type may be used, or a plurality of types may be mixed and used at a predetermined ratio.

Moreover, you may add an inorganic solid material to a raw material liquid. It is possible to change the properties of nanofibers obtained from inorganic solid materials. Examples of inorganic solid materials include metals, oxides, carbides, nitrides, borides, silicides, fluorides, sulfides, and the like. Furthermore, specific examples of the inorganic solid material 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 O ₃ , Yb ₂ O ₃ , HfO ₂ , Nb ₂ O _{5 and the} like can be listed. Moreover, the above-mentioned one type may be used, or a plurality of types may be mixed and used at a predetermined ratio.

  As the solvent that can be used for the raw material liquid, a solvent in which the raw material liquid evaporates (volatilizes) while flying in the space is preferable. Specific examples include acetonitrile, toluene, dichloromethane, alcohols such as methanol and ethanol, and acetone. Furthermore, 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, propyl benzoate, Methyl acetate, ethyl acetate, propyl acetate, dimethyl phthalate, diethyl phthalate, dipropyl phthalate, methyl chloride, ethyl chloride, methylene chloride, chloroform, o-chlorotoluene, 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, Examples include hexane, cyclohexane, cyclohexanone, cyclopentane, o-xylene, p-xylene, m-xylene, acetonitrile, tetrahydrofuran, N, N-dimethylformamide, pyridine, water and the like. Moreover, the above-mentioned one type may be used, or a plurality of types may be mixed and used at a predetermined ratio.

  The proportion of the solvent in the raw material liquid is preferably about 60% to 98%, and is determined by the fiber material to be used, the type of solvent, the diameter of the fiber to be produced, and the like.

  The direction of flight of the injected raw material liquid 300 is changed by the gas flow. Thereby, the injection ports 216 can be arranged vertically or substantially perpendicular to the deposition surface of the nanofiber 301, and a large amount of the raw material liquid 300 can be injected into a certain space. Further, since the gas flow is heated, the evaporation of the solvent is promoted, the electrostatic explosion is promoted, and the nanofiber 301 can be manufactured efficiently.

  Here, the gas flow for changing the flight direction of the raw material liquid 300 to promote the evaporation of the solvent is controlled by the gas flow control means 204 so as not to reach the injection port 216 and the vicinity thereof. Accordingly, since the evaporation of the solvent contained in the raw material liquid 300 is hardly promoted near the injection port 216, the injection port 216 is not narrowed or blocked by the solute. Therefore, even if it continues injecting the raw material liquid 300 from the rotation container 211 for a long period, it can suppress as much as possible that the injection quantity falls. That is, it is possible to maintain the concentration of the raw material liquid 300 and the nanofiber 301 in the space for a long period of time.

  Then, the manufactured nanofiber 301 is transported in a gas flow inside the guide body 206 and reaches the collection body 101 in a high density state. Since the gas flow is sucked from the back (downstream side) by the suction means 102, the collector 101 functions as a filter and separates the nanofibers 301 and the gas flow and collects them while depositing only the nanofibers 301. . The collection body 101 on which the nanofibers 301 are deposited moves at a constant moving speed by the winding of the conveying means 104, and the nanofibers 301 deposited on the collection body 101 together with the collection body 101 while forming a nonwoven fabric. It moves and is wound around the transport means 104.

  As described above, the nonwoven fabric manufacturing apparatus 100 according to the present embodiment makes the concentration in the space of the raw material liquid 300 and the manufactured nanofibers 301 high, and collects the nanofibers 301 in the high concentration state. It becomes possible. Therefore, it becomes possible to continue producing high quality nonwoven fabric stably.

  Although the gas constituting the gas flow is heated by the heating means, the temperature may vary greatly depending on the evaporation rate of the solvent, and as a result of the experiment, the temperature of the gas flow guiding the nanofiber is determined. By controlling the temperature so as to be within a range of 40 ° C. or higher and 80 ° C. or lower, the fiber diameter of the nanofiber is stabilized, and a high-performance nanofiber can be generated.

(Embodiment 2)
Next, another embodiment will be described. Note that in this embodiment, description of portions common to the above embodiment is omitted.

  FIG. 4 is a cross-sectional view schematically showing a nonwoven fabric manufacturing apparatus according to another embodiment.

  The nonwoven fabric manufacturing apparatus 100 includes a nanofiber manufacturing apparatus 200, and the guide body 206 included in the nanofiber manufacturing apparatus 200 includes a bent portion 265 that follows the contraction portion 264. The bent portion 265 is a portion of the guide body 206 that changes the flight direction of the nanofiber 301 by changing the direction of the gas flow. The guide body 206 is provided with a bent portion 265, and thus has a shape in which two cylindrical states having different axial directions are smoothly connected.

  By providing the guide body 206 with the bent portion 265, the raw material liquid 300 in which electrostatic explosion did not occur, the nanofiber 301 in which electrostatic explosion was insufficient and could not be miniaturized, and the sufficiently miniaturized nanofiber 301 were obtained. And only the sufficiently miniaturized nanofiber 301 can reach the collection body 101.

  The guide body 206 includes an expansion portion 266 that follows the contraction portion 264. The expansion unit 266 is contracted by the contraction unit 264 to expand the space where the nanofibers 301 are present at a high density, thereby reducing the density of the nanofibers 301 and dispersing the nanofibers 301 uniformly over a wide range. This is a part of the guide body 206.

  The nonwoven fabric manufacturing apparatus 100 includes a plurality of suction units 102 in a region corresponding to the expanded portion 266, and includes a region regulating unit 103 that is partitioned so as to correspond to each suction unit 102.

  The suction control means 105 is connected to each of the plurality of suction means 102 and can individually control the suction amount of each suction means 102.

  As described above, it is possible to control the flow rate of the gas flow passing through the collector 101 for each region partitioned by the region regulating means 103. That is, the deposition speed of the nanofibers 301 deposited on the collection body 101 can be controlled for each region of the collection body 101. Therefore, it is possible to manufacture a uniform nonwoven fabric by finely controlling the thickness of the nanofiber 301 deposited on the collection body 101.

  In the above embodiment, the injection unit 201 that injects the raw material liquid 300 by centrifugal force is described as an example. However, the injection unit 201 is not limited to this. For example, the charged raw material liquid 300 may be ejected by pressure from a stationary small hole.

  INDUSTRIAL APPLICABILITY The present invention is applicable to a nanofiber manufacturing apparatus, an apparatus for spinning using the manufactured nanofiber, an apparatus for manufacturing a nonwoven fabric using the manufactured nanofiber, and the like.

It is sectional drawing which shows typically the nonwoven fabric manufacturing apparatus which is embodiment of this invention. It is sectional drawing which shows a raw material liquid discharge | release part. It is a perspective view which shows a raw material liquid discharge | release part. It is sectional drawing which shows typically the nonwoven fabric manufacturing apparatus which is other embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Nonwoven fabric manufacturing apparatus 101 Collecting body 102 Suction means 103 Area | region control means 104 Conveyance means 105 Suction control means 106 Solvent recovery apparatus 111 Supply roll 121 Duct 200 Nanofiber manufacturing apparatus 201 Injection means 202 Charging means 203 Gas flow generation means 204 Gas flow control Means 205 Heating means 206 Guide body 207 Static elimination means 211 Rotating container 212 Rotating shaft body 213 Motor 214 Flange portion 216 Injection port 217 Raw material liquid supply path 221 Induction electrode 222 Induction power source 223 Grounding means 231 First gas flow generation means 232 Second gas Flow generation means 233 Gas flow inlet 241 Inlet 242 Outlet 243 Air passage 261 Inlet opening 262 Electrostatic explosive part 263 Static elimination part 264 Shrinking part 265 Bending part 266 Expansion part 290 Raw material liquid releasing part 300 Raw material liquid 301 Nanofiber

Claims (9)

An injection means for injecting a raw material liquid as a raw material of the nanofiber into the space;
Charging means for charging by charging the raw material liquid;
A guide body that forms a wind tunnel for guiding the manufactured nanofiber;
A first gas flow generating means for generating a gas flow arranged outside the guide body and guiding the raw material liquid injected from the injection means into the guide body;
A nanofiber manufacturing apparatus comprising: a second gas flow generating means for generating a gas flow for guiding the nanofibers inside the guide body.   The nanofiber manufacturing apparatus according to claim 1, wherein the guide body includes a bent portion that changes a guide direction of the nanofiber. further,
The nanofiber manufacturing apparatus according to claim 1, further comprising a static elimination unit that neutralizes the manufactured nanofiber. further,
The nanofiber manufacturing apparatus according to claim 1, further comprising a heating unit that heats a gas constituting the gas flow. An injection means for injecting a raw material liquid as a raw material of the nanofiber into the space;
Charging means for charging by charging the raw material liquid;
A guide body that forms a wind tunnel for guiding the manufactured nanofiber;
A first gas flow generating means for generating a gas flow arranged outside the guide body and guiding the raw material liquid injected from the injection means into the guide body;
A second gas flow generating means for generating a gas flow for guiding the nanofibers inside the guide body;
A non-woven fabric manufacturing apparatus comprising a collection body having air permeability and collecting the guided nanofibers. further,
The nonwoven fabric manufacturing apparatus of Claim 5 provided with the suction means which attracts | sucks the gas which comprises the said gas flow to the opposite side to the said nanofiber collection side of the said collection body. A plurality of the suction means are provided,
The nonwoven fabric manufacturing apparatus according to claim 6, further comprising suction control means for individually controlling the suction amount of the suction means. further,
The nonwoven fabric manufacturing apparatus according to claim 6, further comprising a region regulating unit that regulates a suction region of the suction unit on a side opposite to a side on which the nanofibers are collected of the collection body. The collector is a long sheet,
The nonwoven fabric manufacturing apparatus according to claim 5, further comprising a conveying unit that moves the collected body and conveys the deposited nanofibers.

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