JP2019167641A - Electrospinning device and manufacturing method of fiber assembly - Google Patents

Abstract

To provide an electrospinning device of selectively depositing fibers generated by an electrospinning method at a desired position on a target.SOLUTION: An electrospinning device 10 for depositing fibers on a base material 20 having a first surface and a second surface on the opposite side to the first surface comprises: a discharge part 1 discharging raw material liquid of fibers; a collector electrode 2 placed facing the discharge part 1; a holding member 3 holding the base material 20 such that the first surface faces the discharge part 1 between the discharge part 1 and the collector electrode 2; voltage application means for applying voltage between the discharge part 1 and the collector electrode 2; move means for moving the holding member 3 in a plane direction of the first surface; and distance change means for changing a distance A between an apex 2T and the second surface of the base material 20 held by the holding member 3 to control a deposition state on the first surface of the fibers. The collector electrode 2 has a columnar base part 2B and the apex 2T provided at the end portion facing the discharge part 1 of the base part 2B.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an electrospinning apparatus and a method for manufacturing a fiber assembly.

  In an electrospinning method using an electrospinning apparatus, usually, a voltage is applied between a nozzle that discharges a solution (raw material solution) in which a fiber raw material is dissolved and a collector electrode on which a target is placed, and the raw material liquid and Each target is charged to a different polarity. When the raw material liquid is discharged from the nozzle toward the target, electrostatic explosion occurs and the fiber raw material is separated from the raw material liquid. The separated raw material is electrostatically stretched and deposited as fibers on the target.

  In Patent Document 1, the collector electrode is moved in the surface direction of the target in order to deposit the fibers uniformly on the target.

JP 2013-19073 A

  According to the electrospinning method, nano-level fine fibers (nanofibers) are generated. As the use of nanofibers expands, a technique for partially depositing the nanofibers on a desired region on the target is required.

  One aspect of the present invention is an electrospinning apparatus for depositing fibers on a substrate having a first surface and a second surface opposite to the first surface, the raw material liquid for the fibers A discharge portion that discharges the collector, a collector electrode that is disposed opposite to the discharge portion, and the base material between the discharge portion and the collector electrode, wherein the first surface serves as the discharge portion. A holding member to hold, a voltage applying unit for applying a voltage between the ejection unit and the collector electrode, and a moving unit for moving the holding member in the surface direction of the first surface so as to face each other. A distance changing means for changing a distance A between the top portion and the second surface of the base material held by the holding member to control a deposition state of the fiber on the first surface; The collector electrode has a columnar base portion and an end of the base portion facing the discharge portion. And a top portion disposed relates electrospinning device.

  According to another aspect of the present invention, there is provided a preparation step of preparing a raw material liquid containing a raw material of a fiber, and a base material provided with a first surface and a second surface opposite to the first surface, A disposing step of disposing the base material with the first surface facing the discharging unit between a discharging unit that discharges the raw material liquid and a collector electrode disposed to face the discharging unit; An electrospinning step of discharging the raw material liquid from the discharge portion while applying a voltage between the portion and the collector electrode, and the collector electrode is opposed to the discharge portion of the base portion and the discharge portion of the base portion The electrospinning step includes a moving step of moving the base material in the surface direction of the first surface, and the second surface of the base material. The distance for controlling the deposition state of the first surface of the fiber by changing the distance A to the top. Comprising a changing step, the method for producing a fiber assembly.

  According to the present invention, fibers generated by electrospinning can be selectively deposited at desired positions on a target.

It is a side view which shows the structural example of the electrospinning apparatus which concerns on one Embodiment of this invention. It is a perspective view of the electrospinning apparatus shown in FIG. It is the top view which looked at an example of the top part of the collector electrode concerning one embodiment of the present invention from the normal line direction of a substrate. It is a side view which shows a part of collector electrode which concerns on one Embodiment of this invention. It is a perspective view which shows a part of collector electrode which concerns on other one Embodiment of this invention. It is a perspective view which shows a part of collector electrode which concerns on another one Embodiment of this invention. It is a perspective view which shows a part of collector electrode which concerns on another one Embodiment of this invention. It is a perspective view which shows a part of collector electrode which concerns on another one Embodiment of this invention. It is a perspective view which shows a part of collector electrode which concerns on another one Embodiment of this invention. It is a perspective view which shows a part of collector electrode which concerns on another one Embodiment of this invention. It is sectional drawing which shows an example of the discharge part which concerns on one Embodiment of this invention. 2 is a photograph of a fiber assembly obtained by the electrospinning apparatus and the manufacturing method of the present invention.

  During electrospinning, since the raw material liquid is electrostatically exploded, the fibers are generated in a hemispherical region centered on the discharged nozzle, for example. Therefore, it is difficult to partially deposit the fiber on the target. When the target is non-conductive, the target itself is charged with the same polarity as the raw material liquid as the electrospinning progresses. As a result, the electric field in the generation space is deformed, and new fibers may be generated in unintended areas. Therefore, it is difficult to control the position where the target fibers are deposited.

  In the present embodiment, a collector electrode having a columnar portion and a top portion disposed at the end thereof is used. The fiber produced | generated in the production | generation space is drawn near to the part near the target (base material) of the top part of a collector electrode. Therefore, the fibers are selectively deposited on a limited area of the substrate. By moving the substrate in the surface direction, the fibers are deposited on the substrate so as to correspond to the relative movement trajectory of the top. In the present embodiment, the distance between the top and the substrate is further changed to control the fiber deposition state. The fiber deposition state is, for example, a fiber deposition amount and a deposition region. By these, the desired deposition pattern which consists of a fiber assembly can be formed on a base material.

  Hereinafter, the electrospinning apparatus according to the present embodiment will be described with reference to the drawings. FIG. 1 is a side view showing a configuration example of an electrospinning apparatus. FIG. 2 is a perspective view of the electrospinning apparatus shown in FIG. FIG. 3 is a top view of the top of the collector electrode as viewed from the normal direction of the substrate. FIG. 4A is a side view illustrating a part of the collector electrode, and FIGS. 4B to 4G are perspective views illustrating a part of the collector electrode. In the description of the present embodiment, terms (for example, “X, Y, Z”) representing directions are used as appropriate in order to facilitate understanding. However, these are for explanation, and these terms are used in the present invention. It does not limit. Moreover, although the example of illustration shows the case where a base material is a rectangle, the shape of a base material is not limited to this. In FIG. 2, for convenience, the deposited fibers (fiber aggregates) are hatched.

  The electrospinning apparatus 10 holds a discharge unit 1 that discharges a fiber raw material liquid, a collector electrode 2 that is disposed to face the discharge unit 1 and includes a base 2B and a top 2T, and a base material 20 that is a target. And a member 3. The base 2B is columnar. The top portion 2T is disposed at an end portion of the base portion 2B that faces the discharge portion 1. The holding member 3 holds the base material 20 between the discharge part 1 and the top part 2T with the first surface 20X facing the discharge part 1. The electrospinning apparatus 10 further includes a voltage applying unit that applies a voltage between the discharge unit 1 and the collector electrode 2, a moving unit that moves the holding member 3 in the surface direction of the first surface 20X, and a top 2T. Distance changing means (none of which is shown) for changing the distance A between the second surface 20Y of the base material 20 held by the holding member 3 and controlling the accumulation state of the fibers on the first surface 20X; Is provided. Although the collector electrode 2 may be grounded (grounded), it is preferable to apply a voltage opposite to that of the discharge unit 1. This is because the accuracy of the deposition pattern is further improved.

  The raw material liquid discharged from the charging discharge portion is attracted to the collector electrode charged to a polarity different from that of the discharge portion. In an electrospinning apparatus, in order to secure a space (generation space) for electrostatic explosion and electrostatic stretching, and to efficiently deposit fibers on a target substrate, the substrate is usually a collector electrode. Located in the vicinity. The distance between the substrate and the collector electrode has a great influence on the deposition efficiency of the fibers on the substrate.

  In this embodiment, in order to selectively deposit fibers in a limited region of the base material, the collector electrode 2 is provided with a columnar base 2B and a top 2T, and the top 2T and the base held by the holding member 3 are provided. The distance A to the second surface 20Y of the material 20 is changed.

Depending on the distance A, the amount (mass per unit area) and / or region of the fibers deposited on the first surface 20X of the substrate 20 changes. When the distance A exceeds the threshold value A ₀ , the fibers do not accumulate on the base material 20 and, for example, float on the generation space and then adhere to other members of the electrospinning apparatus. When the distance A is equal to or less than the threshold A ₀ , the fibers are attracted to at least a part of the top 2T of the collector electrode 2 and are deposited on a limited region of the substrate 20. Further, when the distance A is equal to or less than the threshold A ₀ , the area where the fibers are deposited decreases as the distance A decreases. That is, even if the discharge of the raw material liquid is continued, the amount and / or region of the deposited fibers can be controlled. And by moving the base material 20 in the surface direction (XY plane direction), as shown in FIG. 2, a fiber is deposited on the part corresponding to the relative movement locus | trajectory on the base material 20 of the top part 2T. be able to. That is, a desired deposition pattern can be formed on the substrate 20.

  In the electrospinning method, since the electric field in the generation space is not stable at the beginning of the discharge of the raw material liquid, the generated fibers tend to be non-uniform. In the present embodiment, since a desired deposition pattern can be formed while continuing to discharge the raw material liquid, a high-quality fiber assembly is formed.

The threshold A ₀ is a distance between the top 2T and the second surface 20Y of the base material 20 and is the maximum distance at which the generated fiber can be deposited on the base material 20. The threshold A ₀ depends on the distance between the discharge part 1 and the top part 2T, the voltage applied between the discharge part 1 and the collector electrode 2, the material of the substrate 20, the material of the holding member 3, the potential of the collector electrode 2, and the like. Set accordingly. Threshold _{A 0} is, for example, 0.5 mm to 2 mm.

The distance A is the shortest distance between the top 2T and the second surface 20Y of the substrate 20. The distance A may or may exceed the threshold value A _0, in some cases the threshold A ₀ or less. The distance A may be 0. In other words, the top 2T and the second surface 20Y of the substrate 20 may be in contact with each other. The distance A is, for example, 0 mm to 3 mm.

  The base material 20 may be slightly pushed up by the top 2T. The maximum distance in the Z direction between the portion pushed up by the top 2T of the substrate 20 and the other portion is, for example, 0 mm to 2 mm. The Z direction is a normal direction of the first surface 20X of the substrate 20.

  The shape of the holding member 3 is not particularly limited as long as the substrate 20 can be held without slack. In particular, the holding member 3 only needs to hold a region (deposition scheduled region 20a) where fibers are to be deposited on the first surface 20X of the base material without slack. When the scheduled deposition region 20a is surrounded by a non-deposition region 20b that does not deposit fibers, the holding member 3 has at least one of the non-deposition region 20b and the region corresponding to the non-deposition region 20b of the second surface 20Y. It is preferable to hold the part. In this case, the distance A between the second surface 20Y and the top portion 2T can be further reduced. For example, the top portion 2T and the second surface 20Y of the substrate 20 can be brought into contact with each other.

  When the outer periphery of the base material 20 is defined, the holding member 3 may be a frame that holds the periphery of the base material 20 as shown in FIG. 2, for example. From the viewpoint of handling properties and storage properties, the holding member 3 may be a rectangular annular body as shown in FIG. 2, and the electric field distribution tends to be uniform in the electrospinning process, and stable electrospinning is possible. From the viewpoint of being easily performed, the holding member 3 may be a circular annular body. The holding member 3 may have a three-dimensional structure that is not entirely on the same plane. Further, a handle may be provided at a position that does not contact the base material 20, or a non-facing portion that does not face the base material 20 may be provided.

  The material of the holding member 3 is not particularly limited, taking into consideration that it is used in an electrospinning process, resistance to a voltage applied in the electrospinning process, resistance to a solvent contained in the raw material liquid, mechanical strength, chargeability, and the like. What is necessary is just to select suitably. In particular, considering that it is used in the electrospinning process, the holding member 3 is preferably an insulator.

  The holding member 3 and the base material 20 are bonded through, for example, an adhesive. The holding member 3 may hold the base material 20 with the first surface 20X, may hold the base material 20 with the second surface 20Y, or the first surface 20X and the second surface 20Y. The substrate 20 may be held on both sides.

  When the base material 20 does not have sufficient strength, a protective material that protects the base material 20 from an external load may be disposed between the second surface 20Y and the top 2T. The protective material is desirably thin, and the thickness is, for example, 0.01 mm or more and 0.2 mm or less. If the thickness of the protective material is within this range, damage to the substrate 20 can be suppressed without hindering the deposition of fibers at a desired position. A protective material is not specifically limited, The same form and material as the base material mentioned later may be sufficient. The protective material is, for example, an insulating film or a non-woven fabric.

  The collector electrode 2 only needs to include the base 2B and the top 2T, and may be formed of only the base 2B and the top 2T. Alternatively, the collector electrode 2 may include a flat plate electrode (not shown) and a base portion 2B and a top portion 2T disposed on the flat plate electrode. The base portion 2B and the top portion 2T may be a single body or separate bodies.

  The base 2B is columnar. The columnar shape is, for example, a rod shape, a pin shape, a pen shape, or the like. The shape of the base 2B viewed from the normal direction of the first surface 20X is not particularly limited, and may be a circle, an ellipse, a rectangle, or another polygon. The base 2B has a rotation axis inside thereof, and may be rotatable around the rotation axis.

The top 2T is disposed at the end of the base 2B on the second surface 20Y side.
The shape (projected figure) of the top 2T viewed from the normal direction of the first surface 20X is not particularly limited, and may be, for example, a circle as shown in FIG. 3, an ellipse, a rectangle, or other various shapes. It may be square or indefinite. The area of the projected figure is not particularly limited, and is set according to the deposition pattern or the like. The area of the projected figure may be, for example, 1/50 to 1/200 of the area of the first surface 20X.

  The overall shape of the top portion 2T is not particularly limited, and may be a hemisphere, a spindle shape, a cylinder, a prism, an arc pillar, or a squeegee, or a shape corresponding to the deposition region. And these combinations may be sufficient (refer to Drawing 4A-Drawing 4G). 4A to 4G show a case where the base 2B is a cylinder as an example.

  The top 2Ta of the collector electrode 2a shown in FIG. 4A is hemispherical. The hemispherical apex 2Ta is preferable in that it does not have a sharp edge. When the top portion 2T has an edge, the electric field tends to concentrate on the edge, and the accuracy of the deposition pattern is likely to decrease. Moreover, when the top part 2T and the 2nd surface 20Y of the base material 20 contact, if the top part 2T is equipped with a sharp edge, the base material 20 will be easily damaged or the smooth movement of the base material 20 will be prevented. It becomes easy.

  In FIG. 4A, the radius of curvature of the top 2Ta is the same as the radius of the base 2Ba, but is not limited to this. The curvature radius of the top portion 2Ta may be smaller or larger than the radius of the base portion 2Ba.

  The top 2Tb of the collector electrode 2b shown in FIG. 4B has a cylindrical shape. According to the columnar top portion 2Tb, a deposition pattern having a relatively thick line can be easily formed. In FIG. 4B, the diameter of the top 2Tb is larger than the diameter of the base 2Bb, but is not limited thereto. The diameter of the top portion 2Tb may be the same as or smaller than the diameter of the base portion 2Ba. A hemispherical or conical protrusion may be provided near the center of the cylinder. A prism may be used instead of the cylinder. The longest side of the prism may be longer or shorter than the diameter of the base 2Bb. The shortest side of the prism may be longer or shorter than the diameter of the base 2Bb.

  The top 2Tc of the collector electrode 2c shown in FIG. 4C has a conical shape. According to the conical top 2Tc, a deposition pattern having fine lines can be easily formed. In FIG. 4C, the diameter of the bottom surface of the top portion 2Tc is the same as the diameter of the base portion 2Bc, but is not limited thereto. The diameter of the bottom surface of the top portion 2Tc may be smaller or larger than the diameter of the base portion 2Bc. Further, a ball-shaped or ring-shaped member may be attached to the tip of the top portion 2Tc. This is to allow the base material 20 to move smoothly.

  The top 2Td of the collector electrode 2d shown in FIG. 4D has a shape corresponding to the deposition region. FIG. 4D shows a ring-shaped top 2Td as an example. According to the top 2Td having a shape corresponding to the deposition region, a desired deposition pattern can be easily formed.

  The top 2Te of the collector electrode 2e shown in FIG. 4E has an arc column shape with an arc having an inner angle of 90 °. However, the thickness of the arc column is not uniform, and gradually decreases from one end of the arc toward the other end. That is, the top portion 2Te includes a squeegee portion. The squeegee portion is disposed so as to face the substrate 20, and the thinnest portion is closer to the substrate 20. As a result, the distance between the top 2Te and the base material 20 and the facing area gradually change. Therefore, it is possible to easily form a deposition pattern having gradation. The inner angle of the top portion 2Te having the arc column shape is not particularly limited to this, and may be 45 ° to 180 °, for example.

  The top 2Tf of the collector electrode 2f shown in FIG. 4F includes two cones 21Tf and a prism 22Tf. The prism 22Tf is a pedestal that supports two cones 21Tf, and the prism 22Tf and each cone 21Tf are joined. Thereby, a deposition pattern having a plurality of thin lines can be easily formed. The number of cones 21Tf may be three or more.

  When the base 2Bf is rotatable, the two cones 21Tf may be arranged so as not to overlap the rotation axis of the base 2B. Thereby, a deposition pattern having a plurality of concentric arcs can be easily formed. Only one cone 21Tf may be arranged so as not to overlap the rotation axis of the base 2B. Also in this case, a deposition pattern having an arc can be easily formed.

  The top 2Tg of the collector electrode 2g shown in FIG. 4G includes a cone 21Tg and an insulating ring 23Tg surrounding the cone 21Tg. The ring 23Tg is a guide that defines the distance between the second surface 20Y and the tip of the cone 21Tg. Thereby, a uniform deposition pattern can be easily formed. The cone 21Tg and the ring 23Tg are each fixed to the base 2Bg. The ring 23Tg may be slidably fixed in the Z direction. Further, a conductive ring larger than the ring 23Tg may be arranged concentrically with the ring 23Tg. In this case, by grounding the conductive rings and changing the electric potential of each ring, the fibers are easily collected in the cone 21Tg, and a desired deposition pattern can be formed more easily.

  In addition, the top portion 2T may include a parabolic antenna-type member having a diameter sufficiently larger (for example, three times or more) than the diameter of the base portion 2B, and a cone disposed at the center thereof. The parabolic antenna type member is provided so that the opening thereof faces the substrate 20. Thus, the fiber accumulation region can be controlled while forming a stable electric field between the discharge unit 1 and the discharge unit 1. Instead of the parabolic antenna type member, a cylinder having a diameter sufficiently larger than the diameter of the base 2B may be used. Instead of a cone, a hemisphere may be arranged at the center of the parabolic antenna type member or the cylinder.

The fibers are deposited on the first surface 20X and in a region (hereinafter, a deposition region) approximately corresponding to the projected figure. When the top portion 2T is, for example, a hemisphere having a curvature radius of 5 mm and the top portion 2T and the second surface 20Y are in contact with each other (A = 0), the deposition region is circular with a diameter of about 2.5 mm to 3 mm. . When a protective material is disposed between the second surface 20Y and the top portion 2T, or when the top portion 2T and the second surface 20Y are not in contact (0 <A ≦ A ₀ ), the diameter of the deposition region Can be slightly larger than 3 mm.

  The entire collector electrode, base 2B or top 2T may be replaceable. Various deposition patterns can be formed on the substrate 20 by using the plurality of top portions 2T having projected figures having different shapes and areas.

  In a preferred embodiment, the distance A is changed by moving the collector electrode 2 instead of the discharge unit 1. Since the distance between the discharge part 1 and the base material 20 does not change, there is little change in the electric field in the generation space, and stable spinning is easily performed. In this case, the mechanism for controlling the movement of the collector electrode 2 and the collector electrode 2 are insulated from the viewpoint of precisely controlling the position of the collector electrode 2.

  The distance A may be changed by moving the holding member 3. When the holding member 3 is insulative, it is not necessary to insulate the holding member 3 from the mechanism that controls the movement of the holding member 3, so that the apparatus can be simplified.

While the raw material liquid is being discharged from the discharge portion 1, particularly while satisfying the condition in which the fibers are deposited on the base material 20 (A <A ₀ ), the discharge portion 1 and the second surface 20Y of the top portion 2T are the most. It is preferable that the direction connecting the close parts (first direction) is kept constant. For example, the distance changing means preferably moves the collector electrode 2 so as to maintain the first direction. When the ejection unit 1 and the collector electrode 2 are moved together, the ejection unit 1 and the collector electrode 2 are moved so as not to change the positional relationship between the X direction and the Y direction. By not changing the direction in which the fibers are attracted (first direction), the spinning is stabilized and the fibers are easily deposited at a desired position.

In particular, it is preferable to move only the base material 20 in the XY direction without moving the discharge unit 1 and the collector electrode while A <A ₀ is satisfied. In other words, the moving means preferably moves the holding member 3 in the XY direction without changing the position in the Z direction. In this case, since the distance A is kept constant together with the first direction, the spinning stability is improved and the accuracy of the deposition pattern is further improved.

  The area and / or shape of the region on which the fibers are deposited and the amount of the fibers to be deposited vary depending on the number, direction, and speed of movement of the substrate 20 in the XY direction. For example, when the base material 20 is moved in the same direction while being gradually shifted, a pattern having a width wider than the width perpendicular to the moving direction of the projected figure or a pattern having gradation can be formed. Moreover, if the base material 20 is repeatedly moved in the same area | region, the mass per unit area of the fiber to accumulate can be increased.

  The amount of fibers deposited can also be changed by moving the holding member 3 or the collector electrode 2 to change the distance A. The amount of fibers deposited can also be changed by changing the applied voltage between the discharge unit 1 and the collector electrode 2, the discharge amount of the raw material liquid from the discharge unit 1, and the potential of the base material 20 or the holding member 3, for example. Yes. Among these, from the viewpoint of electrospinning stability, it is preferable to change the amount of fibers to be deposited by changing the movement speed or distance A of the substrate 20 in the XY direction.

  The first direction is not particularly limited. Considering the spinning stability and the accuracy of the deposition pattern, the smaller angle formed by the first direction and the normal direction (Z direction) of the first surface 20X is preferably 20 degrees or less. That the first direction is constant means, for example, that the change in the first direction is 10 degrees or less. The distance A being constant means, for example, that the change in the distance A is 1/10 or less of the distance A.

  The electrospinning apparatus 10 may further include first detection means for detecting the position of the deposition region and the deposition amount on the first surface 20X. In this case, the position of the deposition region and the deposition amount detected by the first detection unit are fed back to, for example, each control unit that controls the discharge unit 1, the moving unit, and the distance change unit, so The liquid discharge amount, the moving amount and moving direction of the holding member and the collector electrode 2 are determined. Alternatively, a deposition pattern and a deposition amount may be set in advance in each control unit. Thereby, a desired deposition pattern can be easily formed on the substrate 20.

  As the deposition of fibers on the substrate 20 progresses, the substrate 20 is charged with the same charge as the fibers (raw material liquid). Therefore, the base material 20 is likely to be attracted to the top portion 2T having a polarity opposite to that of the raw material liquid, and it may be difficult to control the distance A. The electrospinning apparatus 10 may further include a second detection unit that detects the distance between the second surface 20Y and the top 2T. In this case, the distance A detected by the second detection unit is fed back to the control unit that controls the distance change unit, and the amount of movement of the collector electrode 2 is determined. Alternatively, the electrospinning apparatus 10 may include a static elimination unit that neutralizes the base material 20. The static elimination method is not particularly limited, and a static elimination brush may be used, ion wind generated by corona discharge or the like may be applied to the substrate 20, or ionizing radiation (ultraviolet rays or the like) may be applied to the substrate 20. May be. Especially, it is preferable that static elimination is performed by irradiating an ion wind at the point which is easy to suppress damage to a base material and the some fiber to accumulate (henceforth a fiber assembly).

  The discharge part 1 is comprised with the conductor, The inside is hollow. The raw material liquid is accommodated in the hollow portion. One or more raw material liquid discharge ports are provided on the side of the discharge unit 1 facing the substrate 20. The distance between the discharge port of the discharge unit 1 and the substrate 20 depends on the scale of the electrospinning apparatus 10 and the fiber diameter of the fiber to be generated, but may be, for example, 100 to 600 mm. The raw material liquid is supplied to the hollow portion by the pressure of a pump (not shown) communicating with the hollow portion of the discharge portion 1, and then discharged from the discharge port toward the base material 20. In addition, the structure of the discharge part 1 is not limited to the above.

  The inside (hollow part) of the discharge part 1 may be provided with the 1st flow path 1A which conveys a raw material liquid, and the 2nd flow path 1B which conveys gas, as shown in FIG. The first channel 1A and the second channel 1B are independent. A discharge port (first discharge port 1a) for the raw material liquid 30 is formed at the end of the first flow path 1A facing the base member 20. A gas discharge port (second discharge port 1b) is formed at an end of the second flow path 1B facing the base material 20. The second discharge port 1b is disposed so as to surround the first flow path 1A or the first discharge port 1a. When the raw material liquid is discharged from the first discharge port 1a, the raw material liquid 30 is discharged into the generation space in a state surrounded by the gas by discharging the gas from the second discharge port 1b. Therefore, the spread of electrostatic explosion is suppressed, and the accuracy of the position where fibers are deposited is increased.

  By applying voltage, reactive oxygen species (ROS) and / or reactive nitrogen species (RNS) may be generated from oxygen and / or nitrogen in the atmosphere filling the generation space. By discharging the gas from the second discharge port 1b, the raw material liquid 30 discharged into the generation space can be protected from ROS and RNS. Furthermore, since the charging property around the raw material liquid 30 is lowered, stable electrospinning is easily performed.

  As shown in FIG. 5, it is preferable that the edge part provided with the 1st discharge port 1a of the 1st flow path 1A exists in the position closer to the base material 20 rather than the 2nd discharge port 1b. Since the raw material liquid 30 is discharged into the generation space in a state where an airflow in the direction toward the base material 20 is formed by the gas, the spread of the electrostatic explosion is further easily suppressed. In addition, since the starting point of the electrostatic explosion of the raw material liquid 30 is close to the base material 20, the positional accuracy of the deposition is further increased.

  The gas flow rate is not particularly limited, and may be, for example, 1 liter / minute to 15 liter / minute, or 5 liter / minute to 10 liter / minute. When the gas flow rate is within this range, the spread of electrostatic explosion is likely to be suppressed. The type of gas is not particularly limited, but may be dry air, nitrogen gas, or the like in that it does not affect the fibers that are generated.

  The electrospinning apparatus 10 may include a plurality of discharge units 1. In this case, the discharge part 1 which discharges the raw material liquid 30 is switched as needed.

  The electrospinning apparatus 10 may further include an adsorption mechanism or a suction mechanism for removing unnecessary fibers from the generation space. Unnecessary fibers are fibers that may float in the generation space without reaching the substrate 20. The electrospinning apparatus 10 may include a cleaning mechanism for the discharge unit 1.

Next, the manufacturing method of the fiber assembly which concerns on this embodiment is demonstrated.
The method for producing a fiber assembly includes a preparation step of preparing a raw material liquid containing a raw material of a fiber, and a base having a first surface and a second surface opposite to the first surface, and a raw material liquid Between the discharge unit and the collector electrode, and between the discharge unit and the collector electrode, between the discharge unit and the collector electrode arranged to face the discharge unit And an electrospinning step of discharging the raw material liquid from the discharge portion while applying a voltage to the substrate. The collector electrode includes a columnar base portion and a top portion disposed at an end portion facing the discharge portion of the base portion. In the electrospinning step, the moving step of moving the substrate in the surface direction of the first surface and the distance A between the second surface and the top of the substrate are changed to change the deposition state on the first surface of the fiber. A distance changing step to be controlled. A pattern (deposition pattern) is formed on the substrate by the manufactured fiber assembly.

(Preparation process)
A raw material liquid containing a raw material of the fiber and a base material are prepared.
The raw material liquid contains a fiber raw material and a solvent for dissolving the raw material.

  The raw material of a fiber is not specifically limited, What is necessary is just to select suitably according to a use. Examples of the raw material of the fiber include proteins such as collagen, collagen peptide, gelatin, keratin and silk protein, polysaccharides such as pullulan, cellulose, cellophane, starch, chitin, chitosan, alginic acid, corn starch and salts thereof, polyamide (PA ), Polyimide (PI), polyamideimide (PAI), polyetherimide (PEI), polyacetal (POM), polycarbonate (PC), polyetheretherketone (PEEK), polysulfone (PSF), polyethersulfone (PES) , Polyphenylene sulfide (PPS), polytetrafluoroethylene (PTFE), polyarylate (PAR), polyacrylonitrile (PAN), polyvinylidene fluoride (PVDF), polyvinyl alcohol Le (PVA), polyvinyl acetate (PVAc), polypropylene (PP), polyethylene terephthalate (PET), polyurethane (PU), include polymers such as polystyrene (PS). You may use these individually or in combination of 2 or more types. Moreover, the copolymer using multiple types of monomers which comprise these polymers may be sufficient.

  The solvent is not particularly limited, and may be appropriately selected according to the raw material of the fiber. Examples of the solvent include water, methanol, ethanol, 1-propanol, 2-propanol, isobutyl alcohol, hexafluoroisopropanol, tetraethylene glycol, triethylene glycol, dibenzyl alcohol and other alcohols, 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, benzoate Methyl acid, 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, carbon tetrachloride, 1,1-dichloroethane, 1,2-dichloroethane, trichloroethane, dichloropropane, dibromoethane, dibromopropane, methyl bromide, ethyl bromide, Propyl bromide, acetic acid, benzene, toluene, hexane, cyclohexane, cyclohexanone, cyclopentane, o-xylene, p-xylene, m-xylene, acetonitrile, tetrahydrofuran, N, N-dimethylformamide, N, N-dimethylacetamide, dimethyl Examples thereof include sulfoxide and pyridine. These may be used alone or in combination of two or more.

  The mixing ratio of the solvent and the raw material in the raw material liquid varies depending on the type of the selected solvent and the type of the raw material. The ratio of the solvent in the raw material liquid is, for example, 60% by mass to 98% by mass.

  What is necessary is just to set suitably the viscosity of a raw material liquid so that it may be suitable for discharge of the raw material liquid in an electric field. In particular, the viscosity of the raw material liquid measured by a rotational viscometer at a shear rate of 1 (1 / s) under the condition of 25 ° C. is, for example, 0.1 to 30 Pa · s, and 0.5 to 30 Pa · s. It may be. When the viscosity of the raw material liquid is within this range, stable electrospinning becomes possible.

The size, shape, form and material of the substrate are not particularly limited, and may be appropriately selected depending on the application.
When the periphery of the base material is held by the holding member, it is preferable that the base material is not endless and the outer periphery is defined. On the other hand, the size and shape of the substrate are not limited. The substrate may be, for example, a rectangle with a side of 3 cm to 50 cm, a circle with a diameter of 3 cm to 50 cm, or an indefinite shape with a maximum diameter of 3 cm to 50 cm.

  The form and material of the substrate are not particularly limited and may be appropriately selected depending on the application. Examples of the form of the substrate include fiber structures (woven fabrics, knitted fabrics, nonwoven fabrics and the like), films, sheet-like porous bodies (sponges and the like), and the like.

  Examples of the material of the substrate (fiber substrate) which is a fiber structure include glass fiber, cellulose, acrylic resin, PP, polyethylene (PE), PET, polybutylene terephthalate, PA, or a mixture thereof. .

  The thickness of the fiber substrate may be, for example, 50 μm or more and 500 μm or less, or 150 μm or more and 400 μm or less.

  Examples of the material of the substrate (film substrate) that is a film or the sheet-like porous body include biocompatible polymers. A biocompatible film substrate is suitable for use in contact with the skin. The film substrate may have gas permeability and biodegradability in addition to biocompatibility. A sheet obtained by depositing a protein-containing fiber on a biocompatible film substrate is suitable as a sheet for skin application that can be expected to have a cosmetic effect. In this case, fibers may be selectively deposited on portions corresponding to the eyes and mouth of the film base.

  Examples of the biocompatible polymer include proteins, polysaccharides, polyglycolic acid, polylactic acid, polycaprolactone, PE, polyethylene succinate, PET, polyethylene glycol, polypropylene glycol, polyglutamic acid or salts thereof, polyvinyl alcohol ( PVA), PU, polyanhydrides, or mixtures thereof. Moreover, the copolymer using multiple types of monomers which comprise these polymers may be sufficient.

  From the viewpoint of handling properties, the thickness of the film substrate or the sheet-like porous body may be 50 nm or more, or 100 nm or more. On the other hand, considering the adhesion to the skin, the thickness of the film substrate or sheet-like porous body is preferably 500 μm or less, and more preferably 100 μm or less. In particular, in consideration of gas permeability, the thickness of the film base material is preferably 10 μm or less, and more preferably 1000 nm or less.

(Arrangement process)
The base material is disposed with the first surface facing the discharge portion between the discharge portion that discharges the raw material liquid and the collector electrode that is disposed to face the discharge portion. A base material is arrange | positioned in the state hold | maintained with the frame-shaped holding member, for example. Thereby, the base material is arranged at a predetermined position without slack, preferably in a tensioned state. The holding member and the base material are bonded via, for example, an adhesive.

(Electrospinning process)
The raw material liquid is discharged from the discharge portion while applying a voltage between the discharge portion and the collector electrode, and fibers are deposited on the first surface of the substrate. The collector electrode has a base and a top as described above.

  In the electrospinning step, the substrate is moved in the surface direction of the first surface, and the distance A between the second surface of the substrate and the top of the columnar portion is changed to change the first fiber A distance changing step for controlling the deposition state on the surface is performed.

  The moving process and the distance changing process may be performed simultaneously. In terms of increasing the accuracy of the deposition pattern, it is preferable that the moving step and the distance changing step are executed individually. The moving step and the distance changing step may be performed while discharging the raw material liquid from the discharge unit. This is because whether or not the fibers are deposited on the substrate can be controlled by the distance A.

  In the distance changing step, the distance A is changed by moving the collector electrode. At this time, it is preferable to move the collector electrode so that the first direction connecting the discharge portion and the top portion is kept constant. Alternatively, in the distance changing step, the distance A is changed by moving the base material. In the moving step, it is preferable that the substrate is moved while keeping the distance A constant.

  The average fiber diameter of the fibers to be deposited is not particularly limited, and may be set as appropriate according to the application. The average fiber diameter may be, for example, 50 nm or more and 3 μm or less. In particular, when used as a sheet for skin application, the average fiber diameter is preferably 600 nm or less, more preferably 200 nm or less, and particularly preferably 100 nm or less. This is because the adhesiveness of the skin patch sheet to the skin is enhanced.

  The average fiber diameter is an average value of fiber diameters. The diameter of the fiber is a diameter of a cross section perpendicular to the length direction of the fiber. If such a cross section is not circular, the maximum diameter may be considered as the diameter. Further, the width in the direction perpendicular to the length direction of the fiber when viewed from the normal direction of the first surface of the substrate may be regarded as the fiber diameter. The average fiber diameter is, for example, an average value of diameters at arbitrary locations of arbitrary 10 fibers included in the fiber assembly.

  If necessary, the electrospinning process may be repeated a plurality of times while changing the type of the top and / or the raw material liquid. After the electrospinning step, the solvent contained in the fiber may be removed by air drying, decompression, or heating under conditions that do not damage the fiber assembly.

  FIG. 6 is a photograph of the fiber assembly obtained by the electrospinning apparatus and the manufacturing method according to the present embodiment. Using a collector electrode having a hemispherical (curvature radius of 5 mm) top shown in FIG. 4A, a fiber assembly was deposited in a letter shape on the film substrate. The distance A was 0 mm. The raw material of the fiber is PVDF. The thickness of the character was 3 mm.

  According to the electrospinning apparatus and the manufacturing method of the present invention, the fiber can be deposited at an arbitrary position of the base material, and thus can be used for various applications.

DESCRIPTION OF SYMBOLS 10: Electrospinning apparatus 1: Discharge part 1A: 1st flow path 1a: 1st discharge port 1B: 2nd flow path 1b: 2nd discharge port 2, 2a-2g: Collector electrode 2B, 2Ba-2Bg: Base 2T, 2Ta to 2Tg: Top portion 21Tf, 21Tg: Cone 22Tf: Square column 23Tg: Ring 3: Holding member 20: Base material 20X: First surface 20a: Deposition region 20b: Non-deposition region 20Y: Second surface 30: Raw material liquid

Claims (15)

An electrospinning apparatus for depositing fibers on a substrate having a first surface and a second surface opposite to the first surface,
A discharge part for discharging the raw material liquid of the fiber;
A collector electrode disposed to face the discharge unit;
A holding member that holds the base material between the discharge unit and the collector electrode so that the first surface faces the discharge unit;
Voltage application means for applying a voltage between the ejection part and the collector electrode;
Moving means for moving the holding member in the surface direction of the first surface;
A distance changing means for changing the distance A between the top and the second surface of the base material held by the holding member to control the deposition state of the fiber on the first surface;
The said collector electrode is an electrospinning apparatus provided with the column-shaped base part and the top part arrange | positioned at the edge part which opposes the said discharge part of the said base part.   The electrospinning apparatus according to claim 1, wherein the distance changing unit changes the distance A by moving the holding member.   The electrospinning apparatus according to claim 1, wherein the distance changing unit changes the distance A by moving the collector electrode.   The electrospinning device according to any one of claims 1 to 3, wherein a first direction connecting the discharge portion and the top portion is kept constant while the raw material liquid is discharged from the discharge portion.   The electrospinning apparatus according to claim 4, wherein a smaller angle formed by the first direction and a normal line of the first surface is 20 degrees or less.   The electrospinning apparatus according to claim 1, wherein the moving unit moves the holding member while keeping the distance A constant. The first surface of the substrate has a deposition planned region for depositing the fibers, and a non-deposition region surrounding the deposition planned region,
The electrospinning apparatus according to any one of claims 1 to 6, wherein the holding member holds at least a part of the non-deposition region and a region corresponding to the non-deposition region of the second surface. . The discharge unit includes a first flow path for transporting the raw material liquid therein, and a second flow path for transporting gas independently of the first flow path,
A first discharge port for discharging the raw material liquid is formed at an end portion of the first flow channel facing the base material,
A second discharge port for discharging the gas is formed at an end of the second flow path facing the base material,
The electrospinning apparatus according to claim 1, wherein the second discharge port is disposed so as to surround the first discharge port or the first flow path. A preparation step of preparing a raw material liquid containing a raw material of a fiber, and a base material provided with a first surface and a second surface opposite to the first surface;
An arrangement step of arranging the base material with the first surface facing the discharge section between a discharge section that discharges the raw material liquid and a collector electrode that is disposed to face the discharge section;
An electrospinning step of discharging the raw material liquid from the discharge unit while applying a voltage between the discharge unit and the collector electrode,
The collector electrode includes a columnar base portion and a top portion disposed at an end portion of the base portion facing the discharge portion,
The electrospinning process includes
A moving step of moving the substrate in the surface direction of the first surface;
A distance changing step of changing a distance A between the second surface and the top portion of the base material to control a deposition state of the fiber on the first surface;   The method for producing a fiber assembly according to claim 9, wherein in the distance changing step, the distance A is changed by moving the base material.   The method for manufacturing a fiber assembly according to claim 9, wherein in the distance changing step, the distance A is changed by moving the collector electrode.   The said raw material liquid is discharged from the said discharge part in the said electrospinning process, keeping the 1st direction which ties the said discharge part and the said top part constant. A method for producing a fiber assembly.   The manufacturing method of the fiber assembly according to claim 12, wherein a smaller angle formed by the first direction and a normal line of the first surface is 20 degrees or less.   The method for producing a fiber assembly according to any one of claims 9 to 13, wherein, in the moving step, the base material is moved while the distance A is kept constant. In the arrangement step, the base material is held by a holding member,
The first surface of the substrate has a deposition planned region for depositing the fibers, and a non-deposition region surrounding the deposition planned region,
The fiber assembly according to any one of claims 9 to 14, wherein the holding member holds at least a part of the non-deposition region and a region corresponding to the non-deposition region of the second surface. Manufacturing method.