JP7374672B2 - Electrospinning head and electrospinning device - Google Patents

Description

Embodiments of the present invention relate to electrospinning heads and electrospinning apparatus.

There is an electrospinning device that deposits fine fibers on the surface of a collector or a substrate to form a film of fibers by an electrospinning method (sometimes also referred to as an electrospinning method or a charge-induced spinning method, etc.). The electrospinning apparatus is provided with an electrospinning head, and the electrospinning head includes a head main body and a nozzle protruding from the outer peripheral surface of the head main body. In the electrospinning head, a storage cavity capable of storing a raw material liquid is formed inside the head body. Further, a flow path (nozzle flow path) communicating with the storage cavity is formed inside the nozzle, and an ejection port of the flow path is formed at the end of the nozzle that projects from the head main body. By applying a voltage between the nozzle (electrospinning head) and the collector or the base material, the raw material liquid is jetted from the outlet of the channel toward the surface of the collector or the base material, and the fibers are spun into the collector or the base material. Deposit on the surface of the substrate.

In the above-mentioned electrospinning apparatus, the charge density of the raw material liquid immediately before being ejected from the jetting port is ensured in the flow path of the nozzle to be high, and the raw material liquid is appropriately jetted from the jetting port toward the collector and the base material. What is required is to be done. It is also required that the electric field strength not become excessively high in the space near the protruding end of the nozzle, and that fibers be effectively prevented from adhering to the protruding end of the nozzle and its vicinity.

JP2018-90924A International Publication No. 2012/032777 JP2015-28228A

The problem to be solved by the present invention is to provide an electrospinning head and an electrospinning apparatus that can appropriately jet a raw material liquid from a spout toward a collector and a base material.

According to embodiments, an electrospinning head is provided that includes a head body and a nozzle. In the head body, a storage cavity capable of storing the raw material liquid is formed inside. The nozzle is made of a conductive material and protrudes from the outer peripheral surface of the head body. In the nozzle, a flow path communicating with the storage cavity is formed inside, and an ejection port of the flow path is formed at the end protruding from the head body. The nozzle includes a first extension part and a second extension part. The first extending portion forms a connection portion of the nozzle to the outer circumferential surface of the head main body , and the outer diameter of the first extending portion decreases as it approaches the protruding end of the nozzle. A portion of the first extended portion excluding the flow path becomes the first volume. The second extending portion further projects from the first extending portion in the direction in which the nozzle projects, and forms a projecting end of the nozzle. The part of the second extension part excluding the flow path has a second volume smaller than the first volume, and the second extension part has a smaller dimension along the protruding direction than the first extension part. . The second extension part has a uniform outer diameter, and the outer diameter of the second extension part is the outer diameter of the part of the first extension part other than the connection part to the second extension part. smaller than. The cross-sectional area perpendicular to the extending direction of the flow path is uniform from the connection portion of the nozzle to the outer peripheral surface of the head body to the protruding end of the nozzle. In the first extension part, the wall thickness from the flow path to the outer circumferential surface of the nozzle decreases as it approaches the connection part to the second extension part.

According to an embodiment, an electrospinning device is provided that includes the above-described electrospinning head and a power source. A power supply applies voltage to the nozzle of the electrospinning head.

FIG. 1 is a schematic diagram showing an example of an electrospinning apparatus according to the first embodiment. FIG. 2 is a schematic diagram showing an electrospinning head according to the first embodiment. FIG. 3 is a sectional view schematically showing an electrospinning head according to a first embodiment in a section perpendicular or substantially perpendicular to the longitudinal axis and through one of the nozzles. FIG. 4 is a sectional view schematically showing an electrospinning head according to a first variant in a section perpendicular or substantially perpendicular to the longitudinal axis and passing through one of the nozzles. FIG. 5 is a sectional view schematically showing an electrospinning head according to a second variant in a section perpendicular or substantially perpendicular to the longitudinal axis and passing through one of the nozzles. FIG. 6 is a schematic diagram showing an electrospinning head according to a third modification.

Embodiments will be described below with reference to the drawings.

(First embodiment)
FIG. 1 shows an example of an electrospinning apparatus 1 according to the first embodiment. As shown in FIG. 1, the electrospinning apparatus 1 includes an electrospinning head 2, a supply source (supply section) 3 of a raw material liquid, a power source 4, a collector 5, and a control section 6.

2 and 3 show the structure of the electrospinning head 2. FIG. As shown in FIGS. 1 to 3, the electrospinning head 2 includes a head main body 11 and a plurality of (four in this embodiment) nozzles 12. The head main body 11 (electrospinning head 2) has a longitudinal axis C as a central axis, and extends along the longitudinal axis C. In this embodiment, each of the head body 11 and the nozzle 12 is formed from a conductive material.

Note that the number of nozzles 12 is not particularly limited, and one or more nozzles 12 may be provided. Further, each of the head main body 11 and the nozzle 12 is preferably made of a material that is resistant to the raw material liquid described below, and is made of stainless steel, for example. Here, FIG. 2 shows a state viewed from a certain direction (perpendicular or substantially perpendicular) intersecting the longitudinal axis C. FIG. 3 also shows a cross section perpendicular or substantially perpendicular to the longitudinal axis C and through one of the nozzles 12.

Each of the nozzles 12 is provided on the outer peripheral surface of the head main body 11. The outer circumferential surface of the head body 11 extends around the longitudinal axis C and forms a part of the outer surface of the head body 11 . The outer circumferential surface of the head body 11 faces away from the longitudinal axis C in a direction intersecting (perpendicular or substantially perpendicular to) the longitudinal axis C. Further, in this embodiment, the plurality of nozzles 12 are arranged at the same or substantially the same angular position with respect to each other about the longitudinal axis C. Therefore, in this embodiment, the plurality of nozzles 12 are arranged along the longitudinal axis C to form a nozzle row 13. Further, each of the nozzles 12 protrudes from the outer circumferential surface of the head main body 11 toward the outer circumference, that is, toward the side away from the longitudinal axis C.

A storage cavity 15 is formed inside the head body 11 along the longitudinal axis C. In this embodiment, the storage cavity 15 is formed coaxially or approximately coaxially with the head main body 11, and the central axis of the storage cavity 15 is formed coaxially or approximately coaxially with the longitudinal axis C. Further, the storage cavity 15 is formed over the entire head body 11 or most of the head body 11 in the direction along the longitudinal axis C. Therefore, in this embodiment, the head main body 11 is formed into a cylindrical shape with the storage cavity 15 as an internal cavity.

Further, the same number of channels (nozzle channels) 17 as the number of nozzles 12 are formed in the electrospinning head 2, and a corresponding one of the channels 17 is formed inside each nozzle 12. One end of each channel 17 communicates with the storage cavity 15 and extends from the storage cavity 15 toward the outer circumferential side of the head body 11 . A spout 18 is formed in each of the channels 17 at an end opposite to the storage cavity 15, and each of the channels 17 opens to the outside at the spout 18. In each of the nozzles 12, one ejection port 18 corresponding to the flow path 17 is formed at a protruding end E2 from the outer circumferential surface of the head main body 11.

The raw material liquid supply source 3 includes a storage section 31 , a supply drive section 32 , a supply adjustment section 33 , and a supply pipe 35 . Each of the storage section 31, the supply drive section 32, the supply adjustment section 33, and the supply piping 35 has resistance to the raw material liquid, and in one example, each of the storage section 31 and the supply piping 35 is made of an insulating material such as fluororesin. formed from.

The storage section 31 is a tank or the like that stores the raw material liquid. The raw material liquid is a polymer material dissolved in a solvent. The polymer contained in the raw material liquid and the solvent for dissolving the polymer are appropriately determined depending on the type of fibers 100 to be deposited on the surface of the collecting body 5 and the like. The supply pipe 35 connects the storage section 31 and the head main body 11 of the electrospinning head 2 . A flow path for the raw material liquid is formed inside the supply pipe 35 .

An opening 16 is formed at one end of the storage cavity 15 of the head body 11 . The supply pipe 35 is connected to the head body 11 through the opening 16 , and the storage cavity 15 communicates with the interior of the supply pipe 35 through the opening 16 . In this embodiment, an opening 16 is formed in one end surface of the head body 11 in the direction along the longitudinal axis C. Further, the other end of the storage cavity 15, that is, the end of the storage cavity 15 on the opposite side from the opening 16, is closed to the outside of the head body 11. In one example, the other end of the storage cavity 15 is closed by the head body 11 itself, and in another example, the other end of the storage cavity 15 is closed by a lid member or the like attached to the head body 11.

The supply drive section 32 supplies the raw material liquid from the storage section 31 to the storage cavity 15 of the head main body 11 through the supply pipe 35 by being driven or the like. In one example, supply drive 32 is a pump. In another example, the supply drive section 32 feeds the raw material liquid under pressure from the storage section 31 to the storage cavity 15 by supplying gas to the storage section 31 . The storage cavity 15 can store the raw material liquid supplied through the supply pipe 35.

The supply adjustment unit 33 adjusts the flow rate, pressure, etc. of the raw material liquid supplied to the storage cavity 15. In one example, the supply adjustment unit 33 is a control valve that can control the flow rate, pressure, etc. of the raw material liquid. The supply adjustment unit 33 adjusts the flow rate, pressure, etc. of the raw material liquid to control the amount of water from each spout 18 of the nozzle 12 in a state where no voltage is applied between the electrospinning head 2 and the collector 5. Suppresses spouting of raw material liquid. Then, the supply adjustment section 33 adjusts the raw material liquid to an appropriate flow rate, pressure, etc. based on the viscosity of the raw material liquid and the dimensions of each of the jet ports 18 . In one example, the supply adjustment section 33 can switch between supplying and stopping the supply of the raw material liquid from the storage section 31 to the storage cavity 15. In this case, the supply adjustment section 33 is, for example, a switching valve.

Note that the supply drive section 32 and the supply adjustment section 33 do not necessarily need to be provided. In one example, a storage section 31 is provided vertically above the head body 11, and the raw material liquid is supplied from the storage section 31 to the storage cavity 15 using gravity. In this case, by adjusting the height difference of the housing part 31 with respect to the head main body 11, each spout 18 of the nozzle 12 can be Suppresses spouting of raw material liquid from.

A power source 4 applies a voltage between the electrospinning head 2 and the collector 5 . At this time, in the electrospinning head 2, a voltage of a predetermined polarity is applied to each nozzle 12 via the head main body 11. In one example, a terminal (not shown) electrically connected to each of the nozzles 12 is provided, and a voltage is applied to each of the nozzles 12 via the terminal. In the configuration in which terminals are provided, it is not necessary to form the head main body 11 from a conductive material. As described above, the power source 4 may be configured to apply a voltage to each of the nozzles 12.

Further, the nozzles 12 are electrically connected to each other. Therefore, when a voltage is applied to each nozzle 12, the nozzles 12 have the same or substantially the same potential with respect to each other. The polarity of the voltage applied to each nozzle 12 may be positive or negative. In the example of FIG. 1, the power supply 4 is a DC power supply and applies a positive voltage to each of the nozzles 12.

The collector 5 is formed from an electrically conductive material. In addition, the collector 5 has resistance to the raw material liquid, and in one example is made of stainless steel. The collector 5 is arranged on the side of the electrospinning head 2 where each of the jet ports 18 opens. Therefore, the collector 5 is arranged on the side of the electrospinning head 2 from which the raw material liquid is jetted from the spout 18 .

In the example of FIG. 1, the collector 5 is grounded. Therefore, in a state where a positive voltage is applied to each of the nozzles 12, the ground voltage of the collector 5 becomes 0V or approximately 0V. In another example, the collector 5 is not grounded. The power source 4 then applies a voltage of opposite polarity to the collector 5 to each of the nozzles 12 .

With the raw material liquid being supplied to the electrospinning head 2 by the supply source 3, the power source 4 applies a voltage between each of the nozzles 12 and the collecting body 5 as described above, thereby causing each of the nozzles 12 to eject. The raw material liquid is ejected from the outlet 18 toward the collector 5 . That is, the raw material liquid is ejected toward the collector 5 due to the potential difference between each of the nozzles 12 and the collector 5 . The raw material liquid is ejected from each spout 18 of the nozzle 12 toward the collector 5, so that the fibers 100 are deposited on the surface of the collector 5, and the deposited fibers 100 form a film of fibers 100. . That is, the membrane of the fiber 100 is formed by an electrospinning method (sometimes also referred to as an electrospinning method, a charge-induced spinning method, etc.).

Note that the voltage applied between the electrospinning head 2 and the collector 5, that is, the potential difference between each of the nozzles 12 and the collector 5, depends on the type of polymer contained in the raw material liquid and each of the nozzles 12. The size is adjusted to an appropriate size depending on the distance to the collecting body 5, etc. In one example, a DC voltage having a magnitude of 10 kV or more and 100 kV or less is applied between each of the nozzles 12 and the collector 5.

The collector 5 is formed, for example, in the shape of a plate or a sheet. When the collector 5 is formed in the form of a sheet, the fibers 100 may be deposited on the collector 5 wound around the outer circumferential surface of a roll or the like. Further, the collector 5 may be movable.

In one example, a pair of rotating drums and a drive source for driving the rotating drums are provided. By driving the rotating drums by the drive source, the collector 5 moves between the pair of rotating drums in the same manner as a belt conveyor. By moving (transporting) the collector 5, it is possible to change over time the area on the surface of the collector 5 where the fibers 100 are deposited. This makes it possible to continuously deposit the fibers 100 on the collecting body 5 over time, and a film of the fibers 100, which is a deposit of the fibers 100, is efficiently produced.

The membrane of fibers 100 formed on the surface of the collector 5 is removed from the collector 5. The membrane of the fiber 100 can be used for, for example, but not limited to, nonwoven fabrics, filters, and the like.

Furthermore, in one example, the collector 5 is not provided. In this case, a base material made of a conductive material is used, and by applying a voltage between each of the nozzles 12 and the base material, the raw material liquid is directed from each spout 18 of the nozzle 12 toward the base material. It is squirted. Then, by depositing the fibers 100 on the surface of the base material, a film of the fibers 100 is formed on the surface of the base material. In this case, the substrate may be grounded and a voltage of opposite polarity to each of the nozzles 12 may be applied to the substrate by the power source 4.

In another example, a substrate is placed on the collector 5 and a voltage is applied between each of the nozzles 12 and the collector 5 as described above. Then, the fibers 100 are deposited on the surface of the base material placed on the collector 5 to form a film of the fibers 100 on the surface of the base material. In this case, even if the base material has electrical insulation properties, it is possible to form a film of fibers 100 on the surface of the base material.

Moreover, when a base material is installed on the collection body 5, the base material may be movable on the collection body 5. In one example, a rotating drum around which a sheet-like base material is wound, and a rotating drum that winds up the base material on which a film of fibers 100 is formed are provided. Then, by rotating each of the rotating drums, the base material moves on the collection body 5. By moving (transporting) the substrate, it is possible to change over time the area on the surface of the substrate where the fibers 100 are deposited. This allows the fibers 100 to be deposited continuously on the substrate over time, and a film of the fibers 100, which is a deposit of the fibers 100, is efficiently manufactured.

An example of forming a film of fibers 100 on the surface of a substrate includes, but is not limited to, the production of a separator-integrated electrode for a battery. In this case, one of the negative electrode and the positive electrode of the electrode group is used as the base material. Then, the film of fibers 100 formed on the surface of the base material becomes a separator integrated with the negative electrode or the positive electrode.

The control unit (controller) 6 is, for example, a computer. The control unit 6 includes a processor or integrated circuit (control circuit) including a CPU (Central Processing Unit), an ASIC (Application Specific Integrated Circuit), or an FPGA (Field Programmable Gate Array), and a storage medium such as a memory. The control unit 6 may include only one integrated circuit or the like, or may include a plurality of integrated circuits or the like. The control unit 6 performs processing by executing a program or the like stored in a storage medium or the like. The control unit 6 controls the drive of the supply drive unit 32, the operation of the supply adjustment unit 33, the output from the power source 4, and the like.

Each of the nozzles 12 is, for example, a needle-type nozzle, and has an extension axis P as a central axis. In each of the nozzles 12, one side in the direction along the extension axis P (directions indicated by arrows X1 and X2) coincides or substantially coincides with the direction of protrusion from the outer peripheral surface of the head body 11. Each of the flow passages (nozzle flow passages) 17 is formed coaxially or approximately coaxially with a corresponding one of the nozzles 12, and the center axis of each of the flow passages 17 is coaxial with the extending axis P of the corresponding one of the nozzles 12. Or formed substantially coaxially. Each of the channels 17 is formed along a corresponding extension axis P of the nozzle 12 . Each of the flow paths 17 is formed over the entire dimension in the direction along the extension axis P in a corresponding one of the nozzles 12. Therefore, in this embodiment, each of the nozzles 12 is formed into a cylindrical shape with a corresponding one of the flow paths 17 serving as an internal cavity.

Each of the nozzles 12 includes extensions 21 and 22. In each of the nozzles 12, an extension portion (first extension portion) 21 forms a connection portion E1 to the outer circumferential surface of the head main body 11. Therefore, in each of the nozzles 12, the extension portion 21 forms the root of the portion protruding from the head body 11. Further, in each of the nozzles 12, the extension part (second extension part) 22 further protrudes from the extension part 21 in the projecting direction (direction indicated by arrow X1), and the extension part 22 extends from the head main body 11. A protruding end E2 of the protruding portion is formed. Therefore, in each of the nozzles 12, one of the ejection ports 18 is formed at the protruding end (tip) of the extension portion 22.

Further, a connecting portion E3 of the extension portions 21 and 22 is formed in each of the nozzles 12. In each of the nozzles 12, the extending portion (second extending portion) 22 is connected to the connecting portion E3 on the side where the protruding end E2 is located with respect to the extending portion (first extending portion) 21. be done. Further, in each of the 12 nozzles, a corresponding one of the flow paths 17 sequentially passes through the interior of the extension portion 21 and the interior of the extension portion 22, and from the storage cavity 15 to the spout 18 (projection end E2). It will be extended until Because of the above-described configuration, in each of the nozzles 12, the extending portion 22 becomes the nozzle tip where the protruding end E2 is formed, and the extending portion 21 extends between the head main body 11 and the extending portion 22. It becomes a nozzle relay section for relaying.

In each of the nozzles 12, the cross-sectional area perpendicular to the corresponding extension axis P of the flow path 17 is uniform from the connecting portion E1 to the head body 11 to the protruding end E2. That is, the cross-sectional area perpendicular to the extending direction of each of the flow channels 17 is constant or approximately constant in a corresponding one of the nozzles 12 from the connecting portion E1 to the head body 11 to the protruding end E2. Therefore, in each of the nozzles 12, the cross-sectional area perpendicular to the extending direction of the corresponding one of the flow channels 17 does not change between the connecting portion E1 and the protruding end E2, or is to such an extent that it can be considered that it does not change. It fluctuates minutely. In one example, the outer diameter at the protruding end E2 of the nozzle 12 is designed to be 0.5 mm, and the diameter (inner diameter) of the flow path 17 is designed to be 0.3 mm. In this case, if the diameter of the channel 17 between the connecting portion E1 and the protruding end E2 is within the range of 0.3 mm ± several microns, the cross-sectional area of the channel 17 from the connecting portion E1 to the protruding end E2 is uniform (constant). or approximately constant).

Further, in each of the nozzles 12 of the present embodiment, the outer diameter of the extending portion (second extending portion) 22 is smaller than the outer diameter of the extending portion (first extending portion) 21. That is, the distance from the extension axis P to the outer peripheral surface of the extension part 22 is smaller than the distance from the extension axis P to the outer peripheral surface of the extension part 21. Further, in each of the nozzles 12, the outer diameter of the extending portion 21 is uniform (constant or approximately constant). In each of the nozzles 12, the outer diameter of the extending portion 22 is uniform (constant or substantially constant) from the connecting portion E3 to the extending portion 21 (root of the extending portion 22) to the protruding end E2. In one example, the outer diameter of the extending portion 22, that is, the outer diameter at the protruding end E2 of the nozzle 12 is designed to be 0.5 mm. In this case, if the outer diameter of the extending portion 22 between the connecting portion E3 and the protruding end E2 is within the range of 0.5 mm ± several microns, the outer diameter of the extending portion 22 from the connecting portion E3 to the protruding end E2 is within the range of 0.5 mm ± several microns. It is assumed that the distance from the extension axis P to the outer circumferential surface of the extension portion 22 is uniform between the connection portion E3 and the protruding end E2.

Further, in each of the nozzles 12, it is preferable that the outer diameter of the extending portion (second extending portion) 22, that is, the outer diameter at the protruding end E2, be as small as possible. By reducing the outer diameter of each extending portion 22 of the nozzle 12, electric field concentration tends to occur near each protruding end E2 (spout port 18) of the nozzle 12. In one example, the outer diameter of each extending portion 22 of the nozzle 12 is, for example, between 0.3 mm and 1.3 mm.

Further, the diameter (inner diameter) of each of the flow paths 17, that is, the opening diameter of each of the jet ports 18, is not particularly limited as long as it is smaller than the outer diameter of one corresponding extension portion 22 of the nozzle 12. The diameter of each of the flow channels 17 is appropriately set in accordance with the type of fibers 100 to be deposited on the surface of the collecting body 5. In one example, the diameter of each of the channels 17 is, for example, between 0.1 mm and 1 mm.

Since the outer diameters of the extending portions 21 and 22 are formed as described above, at the connecting portion E3 of the extending portions 21 and 22, the outer diameter of the nozzle 12 increases from the extending portion 21 toward the extending portion 22. Decrease. Therefore, in each of the nozzles 12, a step in the radial direction is formed at the connecting portion E3 of the extension portions 21 and 22. In addition, since the outer diameters of the extending portions 21 and 22 and the diameter of the flow path 17 are formed as described above, in each of the nozzles 12, the wall thickness from the flow path 17 to the outer peripheral surface of the extending portion 22 is , is smaller than the wall thickness of the extending portion 21 from the flow path 17 to the outer peripheral surface. That is, the wall thickness from the flow path 17 to the outer circumferential surface of the extension portion (second extension portion) 22 is equal to the wall thickness from the flow path 17 to the outer circumference surface of the extension portion (first extension portion) 21. smaller than.

Further, in each of the extending portions 21 of the nozzle 12, the wall thickness from the flow path 17 to the outer peripheral surface is the same as that from the connecting portion E1 to the head main body 11 to the connecting portion E3 to the extending portion 22 (the protruding portion of the extending portion 21). It becomes uniform (constant or almost constant) until the end). Therefore, if the wall thickness T1 from the flow path 17 to the outer circumferential surface at the connection part (connection position) E1 to the head main body 11 is defined, in each extension part 21 of the nozzle 12, the connection part E1 and the connection part E3 are defined. The wall thickness from the flow path 17 to the outer circumferential surface is the same or approximately the same as the wall thickness T1 at any location between the two. Further, in each of the extending portions 22 of the nozzle 12, the wall thickness from the flow path 17 to the outer peripheral surface is uniform ( (constant or nearly constant). Therefore, when defining the wall thickness T2 from the flow path 17 to the outer circumferential surface at the protruding end E2, in each extending portion 22 of the nozzle 12, at any location between the connecting portion E3 and the protruding end E2, The wall thickness from the flow path 17 to the outer circumferential surface is the same or approximately the same as the wall thickness T2. In one example, the wall thickness T2 of the extension portion 22, that is, the wall thickness between the flow path 17 and the outer peripheral surface at the protruding end E2 of the nozzle 12, is designed to be 0.2 mm. In this case, if the wall thickness of the extending portion 22 between the connecting portion E3 and the projecting end E2 is within the range of 0.2 mm ± several microns, the wall thickness of the extending portion 22 from the connecting portion E3 to the projecting end E2 is within the range of 0.2 mm ± several microns. Considered to be uniform.

In this embodiment, the wall thickness of the extending portion 22 is smaller than the wall thickness of the extending portion 21, as described above. Therefore, the cross-sectional area of the portion of the extension section 22 excluding the flow path 17 in the cross section perpendicular to the extension axis P is the same as the cross-sectional area of the portion of the extension portion 21 excluding the flow path 17 in the cross section perpendicular to the extension axis P. smaller than the cross-sectional area. That is, in each nozzle 12, the volume occupied per unit length in the direction along the extension axis P (projection direction) is smaller than that of the extension part (first extension part) 21 excluding the flow path. , becomes smaller in the extended portion (second extended portion) 22 except for the flow path.

Furthermore, in each of the nozzles 12, a dimension L2 of the extending portion 22 in the direction along the extending axis P is smaller than a dimension L1 of the extending portion 21 in the direction along the extending axis P. That is, in each of the nozzles 12, the dimension L2 of the extending portion 22 along the protruding direction is smaller than the dimension L1 of the extending portion 21 along the protruding direction. Furthermore, in each of the nozzles 12, the extension length of the flow path 17 from the connecting portion E1 to the head body 11 to the protruding end E2 is the same or approximately the same as the total value (L1+L2) of the dimension L1 and the dimension L2. become.

Here, the volume (first volume) V1 of the portion of the extension portion (first extension portion) 21 excluding the flow path 17, and the flow path 17 of the extension portion (second extension portion) 22. A volume (second volume) V2 of a portion excluding . In this embodiment, the cross-sectional area and dimension L1 of the extension part 21 are as described above, and the cross-sectional area and dimension L2 of the extension part 22 are as described above. Therefore, in each nozzle 12, the volume V2 is smaller than the volume V1.

In the present embodiment, in each of the nozzles 12, the volume (first volume) of the portion of the extension portion (first extension portion) 21 excluding the flow path 17 is larger than the volume (first volume) V1 of the extension portion (second extension portion). The volume (second volume) V2 of the portion of the installation portion 22 excluding the flow path 17 is small. In each of the nozzles 12, a dimension L2 of the extending portion 22 along the protruding direction is smaller than a dimension L1 of the extending portion 21 along the protruding direction. Therefore, in each of the nozzles 12, the protruding length of the extending portion 22 in which the protruding end E2 (spout port 18) is provided becomes small. Since the length of the extension portion 22 protruding from the extension portion 21 in each of the nozzles 12 is reduced, even if a voltage is applied between the nozzle 12 and the collecting body 5, etc., each of the protrusion ends E2 of the nozzle 12 The electric field strength does not become excessively high in the space near . This effectively prevents the fibers (raw material liquid) 100 from adhering to each protruding end E2 of the nozzle 12 and its vicinity while the raw material liquid is being ejected from each of the spout ports 18.

Further, in this embodiment, the wall thickness of the extending portion 22 is smaller than the wall thickness of the extending portion 21. Therefore, by making the dimension L2 of the extending portion 22 along the protruding direction smaller than the dimension L1 of the extending portion 21 along the protruding direction, the volume V2 of the portion of the extending portion 22 excluding the flow path 17 is reduced. A configuration in which the volume of the portion of the installation portion 21 excluding the flow path 17 is smaller than V1 can be easily realized.

Further, in the present embodiment, in each of the nozzles 12, the flow path 17 extends through the extension portions 21 and 22, and extends from the connection portion (root of the protruding portion) E1 to the head body 11 to the protruding end E2. It will be extended. Therefore, in each of the nozzles 12, the extended length of the flow path 17 is the same or approximately the same as the total value (L1+L2) of the dimension L1 and the dimension L2, and becomes larger. By increasing the extension length of the channel 17 in each nozzle 12, the frequency of contact of the raw material liquid flowing through the channel 17 with the inner circumferential surface of each nozzle 12 (the circumferential surface of the channel 17) increases. As the frequency of contact of the raw material liquid with the inner peripheral surface of each of the nozzles 12 increases, electric charges are applied to the raw material liquid from each of the nozzles 12 when a voltage is applied between the nozzle 12 and the collector 5, etc. It becomes easier to move. Thereby, in each of the channels 17, the charge density of the raw material liquid immediately before being ejected from the ejection port 18 is ensured to be high. By increasing the charge density of the raw material liquid immediately before being ejected from the ejection ports 18 in each of the flow paths 17, the raw material liquid is appropriately ejected from each of the ejection ports 18 toward the collector, the substrate, and the like.

Further, in the present embodiment, in each of the nozzles 12, the cross-sectional area (diameter) of the flow path 17 is uniform from the connection portion (connection position) E1 to the head main body 11 to the protruding end E2. Therefore, in each flow path 17 of the nozzle 12, the cross-sectional area perpendicular to the extension axis P becomes small not only at the protruding end E2 and its vicinity, but also at the connection portion E1 to the head body 11 and its vicinity. Therefore, the frequency of contact of the raw material liquid with the inner circumferential surface of each nozzle 12 also increases in the connection portion E1 to the head body 11 and in the vicinity thereof. The charge is more easily transferred from each of the nozzles 12 to the raw material liquid, and the charge density of the raw material liquid immediately before being ejected from the ejection port 18 in each of the channels 17 is further increased.

(Modified example)
Note that in the first modification shown in FIG. 4, in each of the nozzles 12, the outer diameter of the extending portion 21 is equal to the diameter between the connecting portion E1 to the head body 11 and the connecting portion E3 to the extending portion 22 , not uniform. In this modification, the outer diameter of each extending portion (first extending portion) 21 of the nozzle 12 decreases toward the connecting portion E3 to the extending portion 22. Therefore, each extending portion 21 of the nozzle 12 is formed into a tapered shape whose outer diameter decreases as it approaches the protruding end E2. However, in this modification as well, in each of the nozzles 12, the outer diameter of the extending portion 22 is uniform (constant or substantially constant) from the connecting portion E3 to the extending portion 21 to the protruding end E2. In each of the nozzles 12, the outer diameter of the extending portion (second extending portion) 22 of the extending portion (first extending portion) 21 is larger than that of the connecting portion (connecting position) E3. The outer diameter of is small. In this modification, in each of the nozzles 12, the outer diameter at the connecting portion E3 of the extension portions 21 and 22 is the same or approximately the same as the outer diameter at the protruding end E2. Further, unlike the embodiments described above, in each of the nozzles 12, a step in the radial direction is not formed in the connecting portion E3 of the extension portions 21 and 22.

Also in this modification, in each of the nozzles 12, the cross-sectional area perpendicular to the extending direction of the flow path 17 is uniform (constant or substantially constant) from the connection portion E1 to the head body 11 to the protruding end E2. Therefore, in this modification as well, in each extension part (second extension part) 22 of the nozzle 12, the wall thickness from the flow path 17 to the outer peripheral surface is the same as that of the connection part E3 (extension part) to the extension part 21. It is uniform (constant or substantially constant) from the base of the provided portion 22 to the protruding end E2. That is, when defining the wall thickness T2 from the flow path 17 to the outer circumferential surface at the protruding end E2, in each extending portion 22 of the nozzle 12, at any location between the connecting portion E3 and the protruding end E2, The wall thickness from the flow path 17 to the outer circumferential surface is the same or approximately the same as the wall thickness T2.

However, in this modification, in each extension part (first extension part) 21 of the nozzle 12, the wall thickness from the flow path 17 to the outer circumferential surface increases as it goes toward the connection part E3 to the extension part 22. Decrease. Therefore, the wall thickness of each extending portion 21 of the nozzle 12 decreases as it approaches the protruding end E2. Further, in each of the nozzles 12, the wall thickness of the extending portion (second extending portion) 22 is greater than the wall thickness of the extending portion (first extending portion) 21 at a portion other than the connecting portion E3. small. In this modification, in each of the nozzles 12, the wall thickness at the connecting portion E3 of the extension portions 21 and 22 is the same or approximately the same as the wall thickness at the protruding end E2.

Since the configuration is as described above, in each of the nozzles 12, the cross-sectional area of the portion of the extending portion 22 excluding the flow path 17 in the cross section perpendicular to the extending axis P is equal to the extending axis P. The cross-sectional area of the extending portion 21 excluding the flow path 17 is smaller than the cross-sectional area of the extending portion 21 in a cross section perpendicular to . Also in this modification, in each of the nozzles 12, the dimension L2 of the extension part 22 in the direction along the extension axis P is smaller than the dimension L1 of the extension part 21 in the direction along the extension axis P. ,small. Therefore, in this modification as well, in each of the nozzles 12, the volume (first volume) of the portion of the extension portion (first extension portion) 21 excluding the flow path 17 is smaller than the volume (first volume) V1 of the extension portion (first extension portion) 21. The volume (second volume) V2 of the portion of the extended portion 22 excluding the flow path 17 is small. Therefore, this modification also has the same functions and effects as the above-described embodiments.

Also, in the second modification shown in FIG. 5, similarly to the modification shown in FIG. do. In each of the nozzles 12, the outer diameter of the extending portion 22 is uniform (constant or substantially constant) from the connecting portion E3 to the extending portion 21 to the protruding end E2. In each of the nozzles 12, the outer diameter of the extending portion (second extending portion) 22 is greater than the outer diameter of the extending portion (first extending portion) 21 at a portion other than the connecting portion E3. small.

However, in this modification, in each of the nozzles 12, the cross-sectional area perpendicular to the extending direction of the flow path 17 is between the connecting portion E1 to the head main body 11 and the connecting portion E3 of the extending portions 21 and 22. , not uniform. In this modification, each flow path 17 of the nozzle 12 includes a cross-sectional area changing portion 25 formed from a connecting portion E1 to the head main body 11 to a connecting portion E3 of the extension portions 21 and 22; A uniform cross-sectional area portion 26 is provided extending from the connecting portion E3 of the extending portions 21 and 22 to the protruding end E2 (the spout 18). In the cross-sectional area changing portion 25, the closer to the connecting portion E3, that is, the closer to the protruding end E2, the smaller the cross-sectional area perpendicular to the direction in which the flow path 17 extends. Further, in the uniform cross-sectional area portion 26, the cross-sectional area perpendicular to the extending direction of the flow path 17 is uniform (constant or substantially constant) from the connecting portion E3 to the protruding end E2.

Also in this modification, the wall thickness from the flow path 17 to the outer circumferential surface of each extension part (second extension part) 22 of the nozzle 12 is the same as the connection part E3 to the extension part 21 (the extension part 22 It is uniform (constant or substantially constant) from the root of E2 to the protruding end E2. That is, when defining the wall thickness T2 from the flow path 17 to the outer circumferential surface at the protruding end E2, in each extending portion 22 of the nozzle 12, at any location between the connecting portion E3 and the protruding end E2, The wall thickness from the flow path 17 to the outer circumferential surface is the same or approximately the same as the wall thickness T2.

Also in this modification, in each of the nozzles 12, the dimension L2 of the extension part 22 in the direction along the extension axis P is smaller than the dimension L1 of the extension part 21 in the direction along the extension axis P. ,small. Also in this modification, in each of the nozzles 12, compared to the volume (first volume) V1 of the portion of the extension part (first extension part) 21 excluding the flow path 17, the extension part (second volume) is The volume (second volume) V2 of the portion (extending portion) 22 excluding the flow path 17 is small. Therefore, this modification also has the same functions and effects as the above-described embodiments.

Further, as described above, the number of nozzles 12 provided in the electrospinning head 2 may be one or more. Further, in the above-described embodiments, one nozzle row 13 is formed by the plurality of nozzles 12, but in the electrospinning head 2, a plurality of nozzle rows similar to the nozzle row 13 may be formed.

In a third modification shown in FIG. 6, nozzles 12A and 12B are provided on the outer circumferential surface of the head body 11 as the nozzle 12. As shown in FIG. In this modification, a plurality of nozzles 12A and 12B are provided. Further, in this modification, the plurality of nozzles (first nozzles) 12A are arranged at the same or substantially the same angular position with respect to each other about the longitudinal axis C, and the plurality of nozzles (second nozzles) 12B are arranged at the same or substantially the same angular position with respect to each other about the longitudinal axis C. Therefore, in this modification, the plurality of nozzles 12A are arranged along the longitudinal axis C to form a nozzle row (first nozzle row) 13A. Further, the plurality of nozzles 12B are arranged along the longitudinal axis C to form a nozzle row (second nozzle row) 13B.

The nozzle 12B is provided offset from the nozzle 12A about the longitudinal axis C. Therefore, the nozzle row 13B is formed to be shifted from the nozzle row 13A around the longitudinal axis C. However, in this modification, both nozzles 12A and 12B are arranged on the side where the collector 5 is located with respect to the longitudinal axis C. For example, the nozzle 12A is disposed about the longitudinal axis C with a deviation of about 60° from the nozzle 12B.

On the outer peripheral surface of the head main body 11, the nozzles 12A and 12B are arranged in a zigzag pattern. The nozzles 12A and the nozzles 12B are arranged alternately in the direction along the longitudinal axis C. Therefore, a corresponding one of the nozzles (second nozzles) 12B is arranged between adjacent nozzles (first nozzles) 12A in the direction along the longitudinal axis C.

In this modification, the nozzle 12B is arranged between the nozzles 12A adjacent to each other in the direction along the longitudinal axis C. Therefore, in the collecting body 5 or the base material, the fibers 100 are deposited by the nozzles 12B also in the region between the adjacent nozzles 12A in the direction along the longitudinal axis C. This effectively prevents the fibers 100 from being locally deposited on the collector 5 or the substrate.

Also in this modification, the extending portions 21 and 22 are formed in each of the nozzles 12A and 12B in the same manner as in any of the nozzles 12 in the embodiments described above. In each of the nozzles 12A and 12B, a flow path 17 and an ejection port 18 are formed in the same manner as in any of the nozzles 12 in the embodiments described above. Therefore, this modification also provides the same functions and effects as the above-described embodiments.

According to at least one of these embodiments or examples, in the nozzle of the electrospinning head, the second extending part further protrudes from the first extending part in the protruding direction of the nozzle, and the second extending part further protrudes from the first extending part in the projecting direction of the nozzle. , forming the protruding end of the nozzle. The second volume of the part of the second extension part excluding the flow path is smaller than the first volume of the part of the first extension part excluding the flow path. , the dimension along the protruding direction is smaller than that of the first extending portion. Thereby, it is possible to provide an electrospinning head and an electrospinning apparatus that can appropriately eject the raw material liquid from the ejection port toward the collector and the base material.

Although several embodiments of the invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and changes can be made without departing from the gist of the invention. These embodiments and their modifications are included within the scope and gist of the invention, as well as within the scope of the invention described in the claims and its equivalents.
Additional notes are listed below.
[1] A head body in which a storage cavity capable of storing the raw material liquid is formed;
A nozzle is formed of a conductive material and protrudes from the outer circumferential surface of the head main body, and has a flow path communicating with the storage cavity formed therein, and has a flow path formed at an end protruding from the head main body. a nozzle in which a spout is formed;
Equipped with
The nozzle is
a first extending portion that forms a connection portion to the outer circumferential surface of the head main body, and a portion excluding the flow path has a first volume;
A second extending part that further projects from the first extending part in the protruding direction of the nozzle and forms the protruding end of the nozzle, and a portion excluding the flow path has the first volume. a second extension part that has a smaller second volume and a dimension along the protrusion direction that is smaller than the first extension part;
An electrospinning head comprising:
[2] The electric field of [1], wherein the cross-sectional area perpendicular to the extending direction of the flow path is uniform from the connecting portion of the nozzle to the outer peripheral surface of the head main body to the protruding end of the nozzle. spinning head.
[3] The electrospinning head of [1] or [2], wherein the second extending portion has a wall thickness from the flow path to the outer peripheral surface of the nozzle that is smaller than that of the first extending portion. .
[4] The electrospinning head according to [3], wherein in the second extending portion, the wall thickness from the flow path to the outer peripheral surface of the nozzle is uniform up to the protruding end of the nozzle.
[5] The electrospinning head according to [4], wherein in the first extension part, the wall thickness from the flow path to the outer peripheral surface of the nozzle is uniform up to the connection part to the second extension part. .
[6] The electrospinning according to [4], wherein in the first extension part, the wall thickness from the flow path to the outer peripheral surface of the nozzle decreases as it approaches the connecting part to the second extension part. head.
[7] The electrospinning head according to any one of [1] to [6],
a power source that applies voltage to the nozzle of the electrospinning head;
An electrospinning device comprising:

DESCRIPTION OF SYMBOLS 1... Electrospinning device, 2... Electrospinning head, 3... Supply source, 4... Power source, 5... Collection body, 6... Control part, 11... Head main body, 12, 12A, 12B... Nozzle, 17... Channel, 18 ...Ejection port, 21... Extension part (first extension part), 22... Extension part (second extension part).

Claims (5)

a head body in which a storage cavity capable of storing raw material liquid is formed;
A nozzle is formed of a conductive material and protrudes from the outer circumferential surface of the head main body, and has a flow path communicating with the storage cavity formed therein, and has a flow path formed at an end protruding from the head main body. a nozzle in which a spout is formed;
Equipped with
The nozzle is
A first extending portion that forms a connecting portion to the outer circumferential surface of the head main body and has an outer diameter that decreases as it approaches the protruding end of the nozzle, and a portion excluding the flow path is a first extending portion. a first extension having a volume;
A second extending part that further projects from the first extending part in the protruding direction of the nozzle and forms the protruding end of the nozzle, and a portion excluding the flow path has the first volume. a second extension part that has a smaller second volume and a dimension along the protrusion direction that is smaller than the first extension part;
Equipped with
The second extending portion has a uniform outer diameter, and the outer diameter of the second extending portion is equal to that of the portion of the first extending portion other than the connecting portion to the second extending portion. smaller than the outer diameter of the part,
A cross-sectional area perpendicular to the extending direction of the flow path is uniform from the connecting portion of the nozzle to the outer circumferential surface of the head main body to the protruding end of the nozzle,
In the first extension part, the wall thickness from the flow path to the outer peripheral surface of the nozzle decreases as it approaches the connection part to the second extension part.
Electrospinning head. a head body in which a storage cavity capable of storing raw material liquid is formed;
A nozzle is formed of a conductive material and protrudes from the outer circumferential surface of the head main body, and has a flow path communicating with the storage cavity formed therein, and has a flow path formed at an end protruding from the head main body. a nozzle in which a spout is formed;
Equipped with
The nozzle is
A first extension part that forms a connection part to the outer circumferential surface of the head main body and has a uniform outer diameter, the first extension part having a first volume except for the flow path. Department and
A second extending part that further projects from the first extending part in the protruding direction of the nozzle and forms the protruding end of the nozzle, and a portion excluding the flow path has the first volume. a second extension part that has a smaller second volume and a dimension along the protrusion direction that is smaller than the first extension part;
Equipped with
The second extending portion has a uniform outer diameter, and the outer diameter of the second extending portion is smaller than the outer diameter of the first extending portion.
A cross-sectional area perpendicular to the extending direction of the flow path is uniform from the connecting portion of the nozzle to the outer circumferential surface of the head main body to the protruding end of the nozzle,
In the first extension part, the wall thickness from the flow path to the outer circumferential surface of the nozzle is uniform up to the connection part to the second extension part.
Electrospinning head. The electrospinning head according to claim 1 or 2, wherein the second extending portion has a wall thickness from the flow path to the outer circumferential surface of the nozzle that is smaller than that of the first extending portion. 4. The electrospinning head according to claim 3, wherein the second extending portion has a uniform wall thickness from the flow path to the outer peripheral surface of the nozzle up to the protruding end of the nozzle. An electrospinning head according to any one of claims 1 to 4 ,
a power source that applies voltage to the nozzle of the electrospinning head;
An electrospinning device comprising: