Nanofiber sheet, method of using the same, and method of making the same

Abstract

The nanofiber sheet (10) of the present invention comprises: a substrate layer (12); and a nanofiber layer (11) containing nanofibers of a polymer compound disposed on one side of the substrate layer (12). The thickness of the peripheral end (17) of the nanofiber layer (11) is greater than 0.1 μm and less than 10 μm, and has a gradient region (G) in which the thickness gradually increases from the peripheral end (17) toward the inside. The interval W1 between the peripheral end (17) of the nanofiber layer and the maximum thickness portion (15) where the thickness is the largest in the gradient region (G) is greater than 3 mm. The method for manufacturing a nanofiber sheet comprises depositing nanofibers on the collection portion while moving at least one of a nozzle and a collection portion, thereby manufacturing a specified nanofiber sheet having a gradient region (G).

Description

Technical Field

[0001] The present invention relates to nanofiber sheets, methods of using the same, and methods of making the same. Background Art

[0002] As a cosmetic sheet that is attached to the skin and conceals spots or wrinkles, a fiber sheet is known in which fibers (hereinafter referred to as fibers) with a nanometer diameter are deposited by an electrospinning method. For example, Patent Document 1 describes a cosmetic sheet having a hydrophilized substrate sheet, a nanofiber sheet, and an outer sheet. In addition, Patent Document 2 describes a cosmetic sheet comprising a nanofiber nonwoven fabric into which a beauty serum containing components of a molding paste is infiltrated.

[0003] As a method for manufacturing the above-mentioned nanofiber sheet, Patent Document 3 describes a method for manufacturing a nanofiber sheet, in which a polymer solution is discharged from a discharge port to which a high voltage is applied while a jet device is moved in a zigzag shape to deposit nanofibers. In addition, Patent Document 4 describes a method for placing a nanofiber nozzle in a position so that the nanofibers that fall to the outside of the end of the collection sheet are electrically adsorbed to a portion of the back side of the collection sheet. According to Patent Document 4, a sheet is described in which the nanofibers are wound back to the back side of the collection sheet and deposited by the above-mentioned manufacturing method. In addition, Patent Document 5 describes a manufacturing method, which has an end surface treatment means for removing the end in the width direction of a nanofiber nonwoven fabric obtained by an electrostatic spinning method. According to Patent Document 5, a nanofiber sheet having a certain thickness up to the end can be manufactured.

[0004] In addition, Patent Document 6 describes a method for manufacturing a polyurethane nanofiber nonwoven fabric, wherein the tip of a nozzle is moved in a circular motion while discharging a polyurethane resin solution, and the polyurethane resin solution is accumulated in a collector that moves linearly and rotates. Furthermore, Patent Document 7 describes a method for manufacturing a nanofiber membrane, wherein a discharging means is moved back and forth in a plane parallel to a collecting surface disposed opposite thereto, and a raw material liquid is discharged.

[0005] [Prior art literature]

[0006] [Patent Document]

[0007] Patent Document 1: International Patent Publication No. 2014 / 125407

[0008] Patent Document 2: Japanese Patent Application Publication No. 2013-28552

[0009] Patent Document 3: Japanese Patent Application Publication No. 2008-196061

[0010] Patent Document 4: Japanese Patent Application Publication No. 2011-84842

[0011] Patent Document 5: Japanese Patent Application Publication No. 2013-227688

[0012] Patent Document 6: Japanese Patent Application Publication No. 2009-108422

[0013] Patent Document 7: Japanese Patent Application Publication No. 2011-084841 Summary of the invention

[0014] The present invention relates to a nanofiber sheet comprising: a substrate layer; and a nanofiber layer disposed on one side of the substrate layer and containing nanofibers of a polymer compound.

[0015] The nanofiber layer preferably has a thickness at the peripheral edge of not less than 0.1 μm and not more than 10 μm.

[0016] The nanofiber layer preferably has a gradual change region of 3 mm or more in thickness, where the thickness gradually increases inward from the peripheral edge.

[0017] In addition, the present invention relates to a method for using the above-mentioned nanofiber sheet.

[0018] The above-mentioned method of use is preferably performed by bringing the above-mentioned nanofiber layer into contact with the surface of an object and using the nanofiber layer in a wet state.

[0019] Furthermore, the present invention relates to a laminated sheet comprising: a base layer; and an ultra-thin sheet disposed on one surface of the base layer.

[0020] The ultra-thin sheet preferably has a thickness of 5.1 μm or more and 500 μm or less.

[0021] The ultra-thin sheet preferably has an outline shape corresponding to a location where the ultra-thin sheet is applied.

[0022] The ultra-thin sheet preferably has a tapered peripheral region whose thickness gradually increases inward from the peripheral edge.

[0023] The base layer preferably has a region extending outward from the peripheral edge of the ultra-thin sheet.

[0024] The present invention also relates to a method for producing a nanofiber sheet, wherein a raw material liquid is discharged from a nozzle with a high voltage applied between the nozzle and a counter electrode, and nanofibers generated from the raw material liquid are deposited on a collecting portion by electrospinning.

[0025] The manufacturing method preferably deposits the nanofibers on the collecting section while moving at least one of the nozzle and the collecting section.

[0026] The above-mentioned manufacturing method preferably manufactures a predetermined nanofiber sheet having a gradual change region in which the thickness gradually increases from the peripheral edge toward the inner direction.

[0027] In addition, the present invention relates to a manufacturing device for a nanofiber sheet, which comprises: a nozzle for discharging a raw material liquid (spinning liquid); a counter electrode arranged opposite to the nozzle to generate an electric field between the nozzle and the nozzle; a collecting section for accumulating nanofibers generated by electrically stretching the above-mentioned raw material liquid; and a mechanism for moving at least one of the above-mentioned nozzle and the above-mentioned collecting section.

[0028] The manufacturing apparatus may preferably deposit the nanofibers on the collecting section while moving at least one of the nozzle and the collecting section according to data of a moving trajectory input into a control section.

[0029] In the manufacturing apparatus, it is preferred that the control unit has or can have input of data on the movement trajectory determined in the trajectory calculation step.

[0030] Furthermore, the present invention relates to a method for producing an ultra-thin sheet, wherein a raw material liquid is discharged from a nozzle, and fibers or particles generated from the raw material liquid are deposited on a collecting portion to produce the ultra-thin sheet.

[0031] The ultra-thin sheet preferably has a thickness of 5.1 μm or more and 500 μm or less.

[0032] The method for manufacturing an ultra-thin sheet preferably includes a target shape forming step of discharging the raw material liquid within the contour of the ultra-thin sheet while moving at least one of the nozzle and the collecting portion based on information related to the target contour of the ultra-thin sheet.

[0033] In the target shape forming step, the raw material liquid is preferably discharged so as to form a tapered peripheral region within 5 mm in width, the thickness of which gradually increases inward from the peripheral end of the contour shape. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is a schematic plan view showing one embodiment of the nanofiber sheet of the present invention.

[0035] Figure 2 for Figure 1 Sectional view along line II-II.

[0036] Figure 3 for Figure 1 A perspective view of the nanofiber sheet shown.

[0037] Figure 4 For illustration Figure 2 Schematic diagram of the tilt angles of the gradient areas shown.

[0038] Figure 5 To schematically show other embodiments of the nanofiber sheet of the present invention Figure 2 Quite a picture.

[0039] Figure 6 To schematically illustrate other embodiments of the nanofiber sheet of the present invention Figure 2 Quite a picture.

[0040] Figure 7 To schematically illustrate other embodiments of the nanofiber sheet of the present invention Figure 2 Quite a picture.

[0041] Figure 8 For explanation Figure 1 Schematic diagram of the method of using the nanofiber sheet shown.

[0042] Fig. 9 This is a perspective view showing one embodiment of a nanofiber sheet manufacturing apparatus used in the nanofiber sheet manufacturing method of the present invention.

[0043] Fig.10 (a) is a top view showing a nanofiber stack formed by the method for producing a nanofiber sheet of the present invention, Fig.10 (b) is a cross-sectional view taken along line II-II showing the top view.

[0044] Fig.11 (a) is a top view showing a first deposition region and a second band-shaped deposition region formed by the first step and the second step in the deposition step, Fig.11 (b) is a cross-sectional view taken along line III-III of the top view.

[0045] Fig.12 To indicate the formation of Figure 1 A top view of the moving track of the nanofiber sheet is shown.

[0046] Fig.13 A diagram illustrating conditions (1) and (2) in the calculation of J3; Fig.13 (a) is a schematic diagram showing a state where condition (1) is not satisfied. Fig.13 (b) is a schematic diagram showing an embodiment satisfying conditions (1) and (2); Fig.13 (c) is a schematic diagram showing a state where condition (1) is satisfied but condition (2) is not satisfied.

[0047] Fig.14 To represent the calculation Fig.13 A flowchart showing an example of the processing flow of the movement trajectory shown.

[0048] Fig.15 To indicate the formation of Figure 1Top view of other movement tracks of the nanofiber sheet shown.

[0049] Fig.16 This is a perspective view showing another embodiment of the manufacturing apparatus for manufacturing the nanofiber sheet of the present invention.

[0050] Fig.17 This is a perspective view showing another embodiment of the manufacturing apparatus for manufacturing the nanofiber sheet of the present invention.

[0051] Fig.18 This is a perspective view of the brake part used in the manufacturing device of the nanofiber sheet of the present invention.

[0052] Fig.19 for Fig.18 An exploded perspective view of the brake portion shown.

[0053] Fig. 20 This is a perspective view showing another embodiment of the apparatus for producing a nanofiber sheet of the present invention.

[0054] Fig.21 This is a perspective view showing another embodiment of the apparatus for producing a nanofiber sheet of the present invention.

[0055] Fig. 22 Graph showing the cross-sectional profile curve of the nanofiber layer in the reference example.

[0056] Fig.23 This is a top view showing an example of a method for determining a gradient region. DETAILED DESCRIPTION

[0057] When a cosmetic sheet is attached to the skin, the cosmetic sheet may be visible or the presence of the cosmetic sheet may be recognized. In particular, when a cosmetic material such as foundation is attached to the cosmetic sheet after the cosmetic sheet is attached to the skin, the presence of the cosmetic sheet is obvious, making it difficult to achieve a natural appearance.

[0058] The cosmetic sheets of Patent Documents 1 and 2 are still insufficient in achieving a natural appearance because they are visible when attached to the skin. Patent Documents 3 to 7 do not disclose a technique for making the nanofiber sheet attached to the skin difficult to be visually identified.

[0059] Therefore, the present invention relates to a nanofiber sheet, a method of using the nanofiber sheet, a method of manufacturing the nanofiber sheet, and a device for manufacturing the nanofiber sheet that can solve the disadvantages of the prior art.

[0060] The present invention will be described below based on preferred embodiments with reference to the accompanying drawings. Figure 1 to Figure 3 One embodiment of the nanofiber sheet of the present invention is shown.

[0061] Nanofiber sheet 10 Figure 1 As shown, a substrate layer 12 and a nanofiber layer 11 containing nanofibers of a polymer compound are provided. The substrate layer 12 is disposed on one surface of the nanofiber layer 11. In this embodiment, the nanofiber layer 11 and the substrate layer 12 are disposed adjacent to each other.

[0062] The nanofiber layer 11 in the nanofiber sheet 10 is a layer of nanofibers of a polymer compound. The so-called nanofibers in this specification are generally 10 nm or more and 3000 nm or less, and more preferably 10 nm or more and 1000 nm or less when the thickness is expressed in terms of circle equivalent diameter. The thickness of the nanofibers can be measured by, for example, observing the fibers with a magnification of 10,000 times under a scanning electron microscope (SEM), randomly selecting 10 fibers excluding defects (nanofiber piles, intersections of nanofibers, polymer droplets) from the two-dimensional image, drawing a line orthogonal to the length direction of the fibers, and directly reading the fiber diameter.

[0063] The nanofiber layer 11 of this embodiment is as follows Figure 2 As shown in FIG. 1 , the surface opposite to the side where the substrate layer 12 is located has undulations, while the surface opposite to the substrate layer 12 is flat. Hereinafter, the surface opposite to the side where the substrate layer 12 is located in the nanofiber layer 11 is referred to as the first surface S1, and the surface opposite to the substrate layer 12 is referred to as the second surface S2. The nanofiber layer 11 of this embodiment is as shown in FIG. Figure 2 As shown in FIG. 1 , the first surface S1 has a structure that bulges inward. In addition, the nanofiber layer 11 is very thin, but for the sake of convenience, Figure 2 and Figure 3 The nanofiber layer 11 is depicted as being very large.

[0064] The peripheral edge 17 of the nanofiber layer 11 forms the outline of the nanofiber layer 11 in a plan view. In the present embodiment, the peripheral edge 17 is preferably the smallest in thickness in the nanofiber layer 11.

[0065] The thickness D1 of the peripheral edge 17 of the nanofiber layer 11 is 0.1 μm to 10 μm. The thickness D1 of the peripheral edge 17 of the nanofiber layer 11 may differ depending on the position, and the minimum and maximum values ​​of the thickness of the peripheral edge 17 are preferably within the above range.

[0066] The thickness D1 of the peripheral edge 17 (see Figure 2 ) is preferably 0.3 μm or more, more preferably 0.5 μm or more; further, it is preferably 10 μm or less, more preferably 9 μm or less, and even more preferably 8 μm or less; further, it is preferably 0.3 μm or more and 9 μm or less, more preferably 0.5 μm or more and 8 μm or less. The thickness D1 of the peripheral edge 17 can be measured by the following [Method for measuring the three-dimensional shape of the nanofiber layer].

[0067] [Method for measuring the three-dimensional shape of the nanofiber layer]

[0068] The thickness D1 of the peripheral edge 17 of the nanofiber layer 11 is obtained by measuring the surface three-dimensional shape of the first surface of the nanofiber layer using a laser three-dimensional shape measurement system (e.g., a combination of a measurement system EMS2002AD-3D manufactured by COMS and a displacement meter LK-2000 manufactured by KEYENCE). First, the substrate layer is placed on an automatic platform and a nanofiber measurement pitch sheet is placed. Next, the automatic platform is moved in the X-axis direction while the laser displacement meter is scanned to measure the surface three-dimensional shape of the first surface of the nanofiber layer. P The surface height of the first surface of the nanofiber layer is calculated. Then, the automatic stage is offset in the Y-axis direction orthogonal to the X-axis to measure the pitch Y. P , while moving the automatic stage in the X-axis direction, the laser displacement meter scans and repeatedly passes through the specified measurement pitch X P The surface height of the first surface of the nanofiber layer is measured to obtain the surface shape data of the first surface of the nanofiber layer. The calculated pitch in the X-axis direction is set to 0.235 mm, and the calculated pitch in the Y-axis direction is set to 0.235 mm. P It is set to 0.350mm, and the resolution in the height (Z-axis) direction is set to 0.1μm. In addition, the measurement range is set to the range covered by the entire nanofiber layer in the top view, that is, the X-axis direction and the Y-axis direction, and the measurement pitch can be appropriately changed according to the object. The above measurements are performed without load. Then, based on the measured three-dimensional shape data, the thickness of the peripheral end of the nanofiber layer is measured. The details of the method for measuring the thickness of the peripheral end are described below. Unless otherwise specified, the so-called "thickness" in the following description refers to the value measured based on the three-dimensional shape data.

[0069] [Method for measuring the thickness of the peripheral edge]

[0070] First, a plane contour line representing the contour shape of the nanofiber layer when viewed from above is obtained. The plane contour line can be obtained based on the above-mentioned three-dimensional shape data, or it can be obtained by enlarging the observation of the nanofibers using a microscope or the like. A nanofiber layer containing nanofibers generally has fibers extending from the surface, as well as parts with fewer or more localized fibers. Therefore, there are cases where the graphs showing the measured values ​​of the thickness and the like obtained from the above-mentioned three-dimensional shape data at various positions, specifically, the top view contour line or the cross-sectional contour line or the 80% thickness contour line described later, contain noise. From the perspective of removing such noise, the top view contour line or the cross-sectional contour line or the 80% thickness contour line are subjected to approximate curve processing using the polynomial approximation method. In the case where multiple approximate curves are obtained through this processing, the approximate curve closest to the three-dimensional shape data is selected. Next, the top view contour curve that has been approximated to the top view contour line corresponds to the three-dimensional shape data, the peripheral end of the nanofiber layer in the three-dimensional shape data is determined, and the thickness of the peripheral end is measured.

[0071] In simple terms, the thickness D1 of the peripheral edge 17 of the nanofiber layer 11 can also be measured using a contact-type film thickness meter (eg, Litematic VL-50A (R5 mm superhard spherical measuring head) manufactured by Mitutoyo). The load applied to the measurement object during the measurement is set to 0.01 Pa.

[0072] The nanofiber layer 11 has a gradation region G whose thickness gradually increases from the peripheral end 17 toward the inner direction. The gradation region G is a region that bulges inward from the peripheral end 17 and includes the peripheral end 17 of the nanofiber layer 11. The gradation region G is a region that is inclined toward the inner region M in a cross section along a line orthogonal to a center line CL of the outline of the inner region M described later when the first surface S1 of the nanofiber layer 11 is viewed from above (see Figure 2 ). That is, in the above cross section, the surface of the nanofiber layer 11 is an inclined region. The cross section along the above orthogonal line is, for example Figure 1 The II-II line section in FIG. The above section is obtained based on the above three-dimensional shape data. The method for determining the gradient area is described in detail below.

[0073] [Method for determining the gradient area]

[0074] First, in the three-dimensional shape data, the position with the largest thickness is determined as the vertex position, and the thickness of the nanofiber layer at the vertex position is obtained. Next, based on the three-dimensional shape data, the contour line representing the contour of the area whose thickness is 80% of the thickness at the vertex position (hereinafter also referred to as "80% thickness contour line") is obtained, and the position of the contour line is reflected to the three-dimensional shape data together with the top view contour curve. For example, Fig.23As shown, the three-dimensional shape data reflects the top view contour curve C0 and the 80% thickness contour line C80. This 80% thickness contour line is processed using the above-mentioned approximate curve. Next, an arbitrary position on the top view contour curve is set as the first point, and the first to tenth points that divide the perimeter of the top view contour curve into 10 equal parts are set on the top view contour curve. Fig.23 The symbols N1 to N10 shown are examples of the 1st to 10th points. Next, the cross-sectional contour line of the nanofiber layer in the above three-dimensional shape data is obtained at the 1st to 10th points, respectively. The cross-sectional contour line is the contour line of the cross section when the nanofiber layer of the above three-dimensional shape data is cut along the line segment connecting the 1st to 10th points on the top view contour curve with the above 80% contour line at the shortest distance in a top view. Next, the cross-sectional contour lines of the 1st to 10th points are subjected to the above approximate curve processing to obtain the cross-sectional contour curve. Next, in each cross-sectional contour curve obtained, the position of the corresponding 1st to 10th points is reflected, and the position of the peripheral end of the nanofiber layer in the cross-sectional contour curve is determined. Next, in each cross-sectional contour curve obtained, the region where the thickness gradually increases from the peripheral end toward the inner direction of the nanofiber layer and the width of the inclined region is greater than 3 mm is determined. The width is the length from the peripheral end to the vertex position in the cross-sectional contour curve, or the length from the peripheral end to the maximum thickness described later. In addition, as the form of gradual increase in thickness in the cross-sectional profile curve, there can be cited, for example, a linear increase form, a curve increase form such as an S-shaped curve or an exponential function curve, a multi-stage increase form, etc. Then, among the 1st to 10th points, the number of points at which the cross-sectional profile curve having the above-mentioned inclined area is confirmed is measured. When the number of points of the cross-sectional profile curve having the inclined area measured is set to "n", the ratio (%) of the number of cross-sectional profile curves having the inclined area relative to the total of 10 points from the 1st to the 10th point can be calculated by "(n / 10)×100(%)". That is, it can be determined how many % of the gradual change area is relative to the total circumference length of the nanofiber layer. For example, in the case where the cross-sectional profile curve having the above-mentioned inclined area is confirmed at 5 points from the 1st to the 10th points, it can be determined that the nanofiber layer of the measurement object has a 50% gradual change area relative to the total circumference length of the nanofiber layer.

[0075] The various dimensions of the gradual change region G and the inner region M, such as the thickness of the maximum thickness portion 15 or the inclination angle in the gradual change region G described later, are set to the arithmetic mean of the measured values ​​obtained from the cross-sectional profile curve of each point having the above-mentioned inclination region without any special restrictions.

[0076] The nanofiber layer 11 of this embodiment has the above-mentioned gradient region G and an inner region M surrounded by the gradient region G. For the nanofiber layer 11 of this embodiment, Figure 2As shown, the thickness of the gradient region G gradually increases in a single direction, while the thickness of the inner region M is substantially constant. Therefore, the thickness of the inner region M is allowed to be slightly different depending on the position. For example, the thickness is allowed to be different within a range of about ±25% relative to the average thickness. In this embodiment, the thickness of the inner region M is equal to the thickness D3 of the maximum thickness portion 15 of the gradient region G (see Figure 2 ) are the same. The so-called maximum thickness portion 15 of the gradient region G is the portion where the thickness of the gradient region G becomes the largest, which is the inner end of the gradient region G, and in this embodiment, the end on the inner region M side. The inner region M is preferably a region with a thickness of more than 80% relative to the thickness of the vertex position of the nanofiber layer 11, and more preferably a region with a thickness of more than 90%. The inner region M can be determined based on the above-mentioned cross-sectional profile curve. The nanofiber layer 11 may have the gradient region G and the inner region M as in the present embodiment, or may not have the inner region and have a gradient region only between the peripheral end and the vertex position.

[0077] From the perspective of manufacturability and operability, the maximum length of the nanofiber layer 11 when viewed from above is preferably 500 mm or less, more preferably 300 mm or less, and further preferably 150 mm or less. From the same perspective as above, the maximum length of the nanofiber layer 11 when viewed from above is preferably 10 mm or more. The above "maximum length" refers to the maximum straight-line length of the nanofiber layer 11 when viewed from above.

[0078] From the viewpoint of further improving the adhesion of the nanofiber layer 11 to the surface of the object, when the entire circumferential length of the nanofiber layer 11 is set to 100%, it is preferred that the total length of the portion where the gradual change region G exists is 60% or more, more preferably 80% or more, further preferably 90% or more, and even more preferably 100% of the entire circumferential length. From the same viewpoint as above, it is preferred that the gradual change region G exists over the entire circumferential length of the nanofiber layer 11.

[0079] For the convenience of measurement, the ratio of the total length of the portion where the gradual change region G exists to the total length of the periphery of the nanofiber layer 11 can be calculated by the ratio (%) of the number of cross-sectional profile curves having inclined regions to the total 10 points from the 1st to the 10th points obtained by the above-mentioned [gradient region determination method]. For example, when the number of cross-sectional profile curves having inclined regions is "6", the total length of the portion where the gradual change region G exists becomes "60%" to the total length of the periphery of the nanofiber layer 11.

[0080] In the cross section of the nanofiber sheet 10 along the thickness direction, the width W2 of the inner region M (see Figure 2) is less than 200 mm, preferably less than 150 mm. The width W2 of the inner square region M is the distance between the maximum thickness portions 15 of the gradual change region G in the above-mentioned section. The nanofiber sheet 10 of the present embodiment has the inner square region M in the nanofiber layer 11, but the nanofiber sheet 10 may not have the inner square region M. That is, the nanofiber sheet 10 may also have a distance W2 between the maximum thickness portions 15 of the gradual change region G in the above-mentioned section substantially as 0 mm, and only have a gradual change region in which the thickness gradually increases from the peripheral end 17 toward the vertex position. In this case, the maximum thickness portion of the inner square end belonging to the gradual change region G becomes the vertex position.

[0081] The nanofiber layer 11 has a spacing W1 between the peripheral end 17 and the maximum thickness portion 15 of the gradual change region G of 3 mm or more. The spacing W1 between the peripheral end 17 of the nanofiber layer and the above-mentioned maximum thickness portion 15 is the spacing distance from the peripheral end 17 to the portion where the thickness of the gradual change region G becomes the largest, which is the width of the gradual change region G. That is, the nanofiber layer 11 has a gradual change region G of 3 mm or more. In the case where the spacing W1 between the peripheral end 17 and the above-mentioned maximum thickness portion 15, or the spacing W1 between the peripheral end 17 and the vertex position in the nanofiber layer 11 is different depending on the position of the peripheral edge of the nanofiber layer 11, the minimum length of the above-mentioned spacing W1 is sufficient as long as it is 3 mm or more. As mentioned above, in the nanofiber layer 11, the spacing between the peripheral end 17 and the vertex position, or the spacing between the peripheral end 17 and the above-mentioned maximum thickness portion 15 is also referred to as the width W1 of the gradual change region G.

[0082] The nanofiber sheet 10 is used by peeling off the base material layer 12 and sticking the nanofiber layer 11 on an object such as skin.

[0083] The nanofiber sheet 10 is a sheet in which the thickness of the peripheral edge of the nanofiber layer 11 having the gradient region G is set to be greater than 0.1 μm and less than 10 μm, and the width W1 of the gradient region G is set to be greater than 3 mm, so that when attached to an object such as skin, the outer edge of the nanofiber layer 11 is not obvious, and it is difficult to visually identify the nanofiber layer 11. By attaching the nanofiber layer 11 of the nanofiber sheet 10 to the skin, for example, spots or wrinkles on the skin can be effectively concealed, and it is not easy to be aware of the existence of the nanofiber layer 11. In addition, even if cosmetics such as foundation are attached to the nanofiber layer 11 attached to the skin, the outer edge (peripheral end) of the nanofiber layer 11 is still not obvious, resulting in an appearance that blends with the skin and forms a natural makeup look.

[0084] On the other hand, if a cosmetic sheet composed of a nanofiber layer of a certain thickness is attached, the outer edge of the cosmetic sheet is obvious, and it is easy to recognize the existence of the cosmetic sheet, or when a cosmetic material such as foundation is attached to the cosmetic sheet attached to the skin, the outer edge is more obvious and presents a different color tone from the skin, and the cosmetic sheet is easy to identify. In addition, the smaller the maximum thickness of the nanofiber layer, the more difficult it is to obtain the effect of covering spots or wrinkles.

[0085] From the perspective of more effectively exerting the effect of concealing spots or wrinkles, the thickness D3 of the maximum thickness portion 15 of the gradient region G is preferably greater than 5.1 μm, more preferably greater than 10 μm, and preferably less than 500 μm, more preferably less than 400 μm, and further preferably less than 100 μm; and preferably greater than 5.1 μm and less than 500 μm, more preferably greater than 10 μm and less than 400 μm, and further preferably greater than 10 μm and less than 100 μm.

[0086] Furthermore, from the same viewpoint as described above, the thickness at the top position of the nanofiber layer 11 is preferably within the preferred range of the thickness D3 of the maximum thickness portion 15 .

[0087] As described above, the gradient region G is inclined in the cross section along the thickness direction Z of the nanofiber sheet 10. From the viewpoint of making the nanofiber layer 11 less noticeable when attached to the skin, the gradient region G has an inclination angle θ (see Figure 4 ) is preferably 0.001° or more, more preferably 0.002° or more; furthermore, it is preferably 10° or less, more preferably 8° or less; furthermore, it is preferably 0.001° or more and 10° or less, more preferably 0.002° or more and 8° or less. The inclination angle θ of the gradual change region G is the inclination angle (see Figure 4 ). The above-mentioned inclination angle θ can be converted from the thickness D3 of the maximum thickness portion 15 in the gradual change region G, the width W1 of the gradual change region G, and the thickness difference D2 between the peripheral end 17 of the nanofiber layer 11 and the maximum thickness portion 15. The above-mentioned peripheral end 17 and the above-mentioned maximum thickness portion 15 can be determined by the above-mentioned [Method for measuring the thickness of the peripheral end] and [Method for determining the gradual change region].

[0088] From the perspective of enhancing the effect of concealing spots or wrinkles on the skin and making the nanofiber layer less noticeable, the thickness D3 of the maximum thickness portion 15 in the gradient region G (see Figure 2) to the thickness D1 of the peripheral edge 17 (D3 / D1) is preferably 5000 or less, more preferably 4000 or less. For example, it is preferably 50 or more, more preferably 100 or more. In addition, it is preferably 50 or more and 5000 or less, more preferably 100 or more and 4000 or less.

[0089] Furthermore, from the same viewpoint as described above, the ratio of the thickness at the top position of the nanofiber layer 11 to the thickness D1 at the peripheral edge 17 is preferably within the preferred range of D3 / D1 described above.

[0090] From the same viewpoint as above, the thickness difference D2 between the peripheral edge 17 and the maximum thickness portion 15 in the gradual change region G (see Figure 2 ), preferably 5 μm or more, more preferably 10 μm or more; furthermore, preferably 500 μm or less, more preferably 400 μm or less; furthermore, preferably 5 μm or more and 500 μm or less, more preferably 10 μm or more and 400 μm or less. The maximum thickness portion 15 of the gradient region G is the inner square end of the gradient region, that is, the inner square end of the above-mentioned inclined region. The thickness difference between the inner square end and the peripheral end of the gradient region G is equivalent to the thickness difference D2 between the peripheral end 17 of the same region G and the maximum thickness portion 15.

[0091] From the viewpoint of improving the adhesion of the nanofiber layer to the skin, the top view shape of the nanofiber layer 11 is preferably a shape including a plurality of curved portions with different curvatures in its contour, a shape including a plurality of straight portions in its contour, or a shape including the curved portion and the straight portion in its contour. For example, as a shape including a plurality of curved portions with different curvatures in its contour, there can be cited a shape including a curved portion with a plurality of curvatures such as an ellipse in top view, or a shape including a plurality of curved portions with different curvatures forming a concave-convex shape (see Figure 1 ) etc. In addition, as a shape including a plurality of straight line parts in the outline, for example, a polygonal shape such as a rectangle, triangle, quadrangle, hexagon, etc. in top view, or an arrow shape, a star shape, etc. can be cited. Furthermore, as a shape including a curved part and a straight line part in the outline, for example, a fan shape, a tear shape, a semicircle shape, a heart shape, etc. can be cited. The nanofiber layer 11 of such a shape can easily follow a complex shape such as a face and can be easily attached.

[0092] From the viewpoint of further improving the above-mentioned adhesion, the contour line of the nanofiber layer 11 when viewed from above is preferably composed of a curve for more than half of its total length. At this time, from the viewpoint of further improving the followability of the nanofiber layer 11 to the surface of the object, the contour line of the nanofiber layer 11 when viewed from above is preferably composed of a curve for more than 60%, more preferably more than 70%, and even more preferably more than 80% of its total length, and even more preferably the entire length of the contour line is composed of a curve. The above-mentioned contour line of the nanofiber layer 11 when viewed from above can be determined by the plane contour curve in the above-mentioned [Method for measuring the thickness of the peripheral end].

[0093] The base layer 12 is a layer that can maintain the shape retention of the nanofiber sheet, and may be a single layer or a plurality of layers.

[0094] As the substrate layer 12, for example, a film made of synthetic resin, such as polyolefin resin or polyester resin, or a fiber sheet such as nonwoven fabric can be used. When the substrate layer 12 is laminated on the nanofiber layer 11 in a releasable manner, it is preferred to apply a silicone resin coating or a corona discharge treatment to the surface of the film facing the nanofiber layer 11 in advance from the viewpoint of improving the releasability. In addition, from the viewpoint of improving the releasability, when a film made of synthetic resin is used as the substrate layer 12, it is preferred to provide a powder or particle layer formed by dispersing powder or particles on the surface of the film.

[0095] The nanofiber sheet 10 of this embodiment is an integrated nanofiber layer 11 and a substrate layer 12 before use. When used, the nanofiber layer 11 and the substrate layer 12 are peeled off to remove the substrate layer 12. From the perspective of improving the workability of peeling off the nanofiber layer 11 and the substrate layer 12, the substrate layer 12 is preferably air-permeable. Thus, air enters between the nanofiber layer 11 and the substrate layer 12, and the nanofiber layer 11 and the substrate layer 12 can be easily peeled off.

[0096] As the air-permeable substrate layer 12, it is preferred to use a fiber sheet or a sponge. Specifically, the fiber sheet includes various nonwoven fabrics, woven fabrics, knitted fabrics, paper, meshes, and laminates (laminated bodies) thereof. As nonwoven fabrics, for example, meltblown nonwoven fabrics, spunbonded nonwoven fabrics, hot air nonwoven fabrics, and water needle nonwoven fabrics can be used, but are not limited to this. The fibers or strands constituting these nonwoven fabrics or meshes may have a thickness in the range of nanofibers or be relatively thick. In addition, as fibers, fibers composed of fiber-forming synthetic resins or cellulose-based natural fibers such as cotton and wood pulp can be used. Sponges are specifically porous materials that foam synthetic resins or natural resins, for example, composed of foamed resins. As synthetic resins or natural resins, for example, urethane, polyethylene, melamine, natural rubber, chloroprene rubber, ethylene propylene rubber, nitrile rubber, silicone rubber, fluororubber, etc. can be used, but are not limited to this. As the foaming resin, various materials can be used as long as they can be formed into an air-permeable shape.

[0097] From the viewpoint of making it easier to adhere the nanofiber layer 11 to the skin, the base material layer 12 is preferably a nonwoven fabric.

[0098] The substrate layer 12 disposed adjacent to the nanofiber layer 11 preferably has a plurality of concave or convex portions having a width greater than the diameter of the nanofibers on the surface facing the nanofiber layer 11. This configuration is advantageous in improving the operation of peeling the nanofiber layer 11 from the substrate layer 12 when the substrate layer 12 is not breathable.

[0099] The thickness of the base material layer 12 is preferably 5 μm or more, more preferably 10 μm or more, and preferably 20 mm or less, more preferably 15 mm or less; and preferably 5 μm or more and 20 mm or less, more preferably 10 μm or more and 15 mm or less.

[0100] The nanofiber sheet 10 can also be used in a state where a liquid such as a beauty serum is contained in the nanofiber layer 11. In this case, from the viewpoint of preventing the nanofiber layer 11 from being dissolved by a liquid such as a beauty serum, the nanofiber layer 11 is preferably water-insoluble. The so-called water-insoluble means that, in an environment of 1 atmosphere and 23°C, after weighing 1 g of the nanofiber layer 11 and immersing it in 10 g of ion exchange water, more than 0.5 g of the immersed nanofiber layer 11 does not dissolve after 24 hours, and preferably more than 0.8 g of the immersed nanofiber layer 11 does not dissolve after 24 hours. In other words, the so-called water-insoluble means that, in an environment of 1 atmosphere and 23°C, after weighing 1 g of the nanofiber layer 11 and immersing it in 10 g of ion exchange water, less than 0.5 g of the immersed nanofiber layer 11 dissolves after 24 hours, and preferably less than 0.2 g of the immersed nanofiber layer 11 dissolves after 24 hours.

[0101] The nanofiber layer 11 is formed by depositing nanofibers containing a polymer compound capable of forming fibers. From the viewpoint of making the nanofiber layer 11 water-insoluble, the nanofiber layer 11 preferably contains nanofibers of a water-insoluble polymer compound as the polymer compound capable of forming fibers. With this configuration, even if the nanofiber layer contains a water-soluble component used in cosmetics, the shape retention of the nanofiber layer 11 can be maintained. As water-insoluble polymer compounds, for example, fully saponified polyvinyl alcohol that can be insolubilized after nanofiber formation, partially saponified polyvinyl alcohol that can be cross-linked after nanofiber formation by using a cross-linking agent, oxazoline-modified polysiloxanes such as poly(N-propionylethyleneimine) grafted-dimethylsiloxane / γ-aminopropylmethylsiloxane copolymers, zein (the main component of zein), or polyester resins such as polylactic acid (PLA), polyethylene terephthalate resin, polybutylene terephthalate resin, acrylic resins such as polyacrylonitrile resin and polymethacrylic resin, polyamide resins such as polystyrene resin, polyvinyl butyral resin, polyurethane resin, nylon, polyimide resin, polyamide-imide resin, etc. These water-insoluble polymer compounds can be used alone or in combination of two or more.

[0102] The nanofiber layer 11 may also contain nanofibers of water-soluble polymer compounds. As water-soluble polymer compounds, for example, mucopolysaccharides such as pullulan, hyaluronic acid, chondroitin sulfate, poly-γ-glutamic acid, modified corn starch, β-glucan, oligosaccharide, heparin, keratan sulfate, cellulose, pectin, xylan, lignin, polyglucomannan, galacturonic acid, psyllium seed gum, tamarind gum, gum arabic, tragacanth gum, soybean water-soluble polysaccharide, alginic acid, carrageenan, laminarin, agar (agarose), fucose, methylcellulose, hydroxypropylcellulose, hydroxypropylmethylcellulose, etc., synthetic polymers such as partially saponified polyvinyl alcohol (when a cross-linking agent is not used in combination), low saponified polyvinyl alcohol, polyvinyl pyrrolidone (PVP), polyethylene oxide, water-soluble nylon, water-soluble polyester, sodium polyacrylate, etc. can be cited. These water-soluble polymer compounds can be used alone or in combination of two or more.

[0103] Nanofiber layer 11 may also contain other polymer compounds other than the above-mentioned water-insoluble polymer compound and water-soluble polymer compound. As other polymer compounds, generally, polypropylene, polyethylene, polystyrene, polyvinyl alcohol, polyurethane, polyethylene oxide, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyisophenylene terephthalate, polyisophenylene terephthalate, polyvinylidene fluoride, polyvinylidene fluoride-hexafluoropropylene copolymer, polyvinyl chloride, polyvinylidene chloride-acrylate copolymer, polyacrylonitrile, polyacrylonitrile-methacrylate copolymer, polycarbonate, polyarylate, polyester carbonate, nylon, aramid, polycaprolactone, polylactic acid, polyglycolic acid, collagen, polyhydroxybutyric acid, polyvinyl acetate, polypeptide, etc. can be cited. These polymer compounds can be used alone or mixed with multiple uses.

[0104] In the case of making the nanofiber layer 11 water-insoluble, the water-insoluble polymer compound contained in the nanofiber layer 11 is preferably greater than 50 mass %, more preferably greater than 80 mass %, relative to the total mass of the nanofiber layer 11; the water-soluble polymer compound contained in the nanofiber layer 11 is preferably less than 50 mass %, more preferably less than 20 mass %, relative to the total mass of the nanofiber layer 11.

[0105] The nanofiber layer 11 may be composed of nanofibers only, or may contain other components in addition to nanofibers. As substances other than nanofibers as other components, components used in cosmetics can be used. For example, medicinal ingredients, moisturizing ingredients, various vitamins, spices, ultraviolet protection agents, surfactants, coloring pigments, body pigments, dyes, stabilizers, preservatives and antioxidants can be cited. These components can be used alone or in combination of two or more.

[0106] When the nanofiber layer 11 contains other components in addition to the nanofibers, the content of the nanofibers in the nanofiber layer 11 is preferably 40 mass % to 95 mass %, more preferably 70 mass % to 90 mass %.

[0107] The content of other components in the nanofiber layer 11 is preferably 5 mass % or more and 60 mass % or less, and more preferably 10 mass % or more and 30 mass % or less.

[0108] In the case where the nanofiber layer 11 is formed of nanofibers containing other components, for example, the nanofibers can be obtained by mixing and modulating a water-soluble polymer compound and other components in a state where they are completely dissolved in water. In addition, the nanofibers can also be obtained by using nanofibers having a hollow portion and containing an emulsified component of other components in the hollow portion. Depending on the type of reaction of the other components, they can be contained in the nanofiber alone or in two or more types.

[0109] From the viewpoint of effectively covering spots and wrinkles on the skin, the basis weight of the inner area M of the nanofiber layer 11 is 0.01 g / m 2 More preferably 0.1 g / m 2 In addition, preferably 50g / m 2 Below, more preferably 40g / m 2 In addition, preferably 0.01g / m 2 Above and 50g / m 2 Below, more preferably 0.1g / m 2 Above and 40g / m 2 The basis weight of the inner area M of the nanofiber layer 11 can be obtained by cutting out a 10 mm x 10 mm piece from the inner area M, weighing the piece with a scale, and dividing the result by the area of ​​the piece (100 mm). 2 ) is calculated and measured. In addition, based on the same viewpoint as above, the basis weight at the top position of the nanofiber layer 11 is preferably within the preferred range of the basis weight of the inner area M.

[0110] In the above embodiment, the inner area M covers the entire area and has a substantially constant thickness. Figure 5 and Figure 6 As shown, the inner area M may also have different thicknesses depending on the position. Figure 5 and Figure 6 The illustrated embodiment is a description of the nanofiber sheet of the above-mentioned embodiment to which the description is appropriately applied unless there is any contradiction. Figure 5 The nanofiber sheet 10a shown in the figure has a plurality of recesses 18 of different depths on the first surface S1 side of the inner region M. The thickness D5 of the recesses 18 in the inner region M (see Figure 5 ), which is smaller than the thickness D3 of the maximum thickness portion 15 of the gradual change region G. From the perspective of improving the adhesion of the nanofiber layer 11, the thickness D5 of the concave portion 18 of the inner region M (see Figure 5 ) is preferably 50% or more, more preferably 60% or more; furthermore, it is preferably 100% or less, more preferably 90% or less; furthermore, it is preferably 50% or more and 100% or less, more preferably 60% or more and 90% or less.

[0111] In addition, from the viewpoint of improving the hiding property of the spots or wrinkles of the nanofiber layer 11, the thickness D5 of the concave portion 18 of the inner region M (see Figure 5) is preferably 5.1 μm or more, more preferably 10 μm or more; furthermore, preferably 500 μm or less, more preferably 400 μm or less; furthermore, preferably 5.1 μm or more and 500 μm or less, more preferably 10 μm or more and 400 μm or less. In the case where the thickness D5 of the concave portion 18 of the inner square region M is different in each concave portion 18, it is preferred that the minimum value of the thickness D5 of the concave portion 18 of the inner square region M is within the above range.

[0112] In addition, for the inner area M, if Figure 6 As shown in the nanofiber sheet 10b, in addition to the recess 19a having a thickness greater than the maximum thickness portion 15 of the gradient region G, it may also have a recess 19b having a thickness less than the maximum thickness portion 15. Hereinafter, in the inner region M, the recess 19a having a thickness greater than the maximum thickness portion 15 of the gradient region G is sometimes referred to as a shallow recess 19a, and the recess 19b having a thickness less than the maximum thickness portion 15 of the gradient region G is sometimes referred to as a deep recess 19b. The inner region M is further outward than the shallow recess 19a and forms a deep recess 19b along the periphery of the inner region M. Furthermore, the thickness of the inner region M gradually increases from the bottom of the deep recess 19b toward the inside. That is, Figure 6 In the illustrated embodiment, the nanofiber layer 11 has: a gradual change region G1 formed along the peripheral edge thereof; and a gradual change region G2 formed along the peripheral edge of the inner region M and located further inward than the gradual change region G1 .

[0113] From the perspective of improving the hiding power of the spots or wrinkles of the nanofiber layer 11, the inner area M is a thickness D7 of the shallow concave portion 19a (see Figure 6 ) is greater than the thickness D3 of the maximum thickness portion 15 of the gradient region G, preferably 5.1 μm or more, more preferably 10 μm or more; furthermore, preferably 500 μm or less, more preferably 400 μm or less; furthermore, preferably 5.1 μm or more and 500 μm or less, more preferably 10 μm or more and 400 μm or less. In the case where the thickness D7 of the shallow concave portion 19a of the inner region M is different in each shallow concave portion, it is preferred that the minimum value of the thickness D7 is within the above range.

[0114] From the same point of view as above, the inner area M is based on the premise that the thickness D9 of the deep concave portion 19b is smaller than the thickness D3 of the maximum thickness portion 15 and the thickness D7 of the shallow concave portion 19a. Figure 6) is preferably 5.1 μm or more, more preferably 10 μm or more; furthermore, preferably 500 μm or less, more preferably 400 μm or less; furthermore, preferably 5.1 μm or more and 500 μm or less, more preferably 10 μm or more and 400 μm or less. In the case where the thickness D9 of the deep concave portion 19b of the inner area M is different in each deep concave portion, it is preferred that the minimum value of the thickness D9 is within the above range.

[0115] In the case where the nanofibers, i.e., the fibers, are directly deposited on the substrate layer, the nanofiber layer 11 is disposed adjacent to the substrate layer 12. The nanofiber layer 11 and the substrate layer 12 may also be disposed adjacent to each other, for example, Figure 7 As shown, an adhesive layer that can be attached to the surface of an object may be present between the base material layer 12 and the nanofiber layer 11 .

[0116] In addition, from the perspective of making it easy to attach the nanofiber sheet to the skin, the nanofiber sheet preferably has an adhesive layer 13 that can be attached to the surface of an object. The adhesive layer 13 is used to attach the nanofiber layer 11 to an object such as skin. The adhesive layer 13 can be arranged between the substrate layer 12 and the nanofiber layer 11, that is, on the second surface S2 side of the nanofiber layer 11, and can also be arranged between the substrate layer 12 and the opposite side of the nanofiber layer 11, that is, on the first surface S1 side of the nanofiber layer 11.

[0117] From the viewpoint of maintaining the adhesive force of the adhesive layer 13, Figure 7 As shown, the adhesive layer 13 is preferably disposed on the second surface S2 side of the nanofiber layer 11 . Figure 7 The nanofiber sheet 10c shown is used by attaching the adhesive layer 13 to the skin after peeling the adhesive layer 13 and the base layer 12 apart.

[0118] The nanofiber sheet in which the adhesive layer 13 is disposed on the first surface S1 side of the nanofiber layer 11 is used by attaching the adhesive layer 13 to the skin after or before peeling the substrate layer 12 and the nanofiber layer 11 .

[0119] As the adhesive constituting the adhesive layer 13, oxazoline-modified polysiloxane, acrylic resin, olefin resin, synthetic rubber, etc. can be used. From the viewpoint of maintaining high adhesive strength, acrylic resin is preferably used as the adhesive constituting the adhesive layer 13.

[0120] There is no particular restriction on the thickness of the adhesive of the adhesive layer 13. From the perspective of more securely attaching the nanofiber layer 11 to the skin and enhancing the skin touch or feel of the nanofiber sheet, the thickness of the adhesive of the adhesive layer 13 is preferably greater than 10 nm, more preferably greater than 50 nm; in addition, it is preferably less than 100 μm, more preferably less than 50 μm; in addition, it is preferably greater than 10 nm and less than 100 μm, more preferably greater than 50 nm and less than 50 μm.

[0121] In the nanofiber sheet 10c, any one of the nanofiber layer 11, the substrate layer 12, and the adhesive layer 13 may be peelable, or each layer may be independently peelable. Specifically, the substrate layer 12, the adhesive layer 13, and the nanofiber layer 11 may be peelable, or the substrate layer 12, the adhesive layer 13, and the nanofiber layer 11 may be peelable, or each layer may be independently peelable. In order to form a peelable layer, it is possible to laminate the layers under the condition that Van der Waals force or electrostatic force is generated between the peeling target layer and the non-peeling target layer, or to apply a peeling treatment such as silicone resin coating or corona discharge treatment to the surface of the peeling target layer opposite to the non-peeling target layer.

[0122] Next, a method of using the nanofiber sheet of the present invention will be described with reference to the drawings according to a preferred embodiment. Figure 8 (a) to (c) indicate the use of Figure 1 The nanofiber sheet 10 is shown in one embodiment of a method for using the nanofiber sheet.

[0123] In the method of using the nanofiber sheet 10, the nanofiber sheet 10 is attached to the surface of an object, that is, it is used by attaching it. The object of the nanofiber sheet 10 is the object to which the nanofiber layer 11 is attached. The above-mentioned object mainly includes, in addition to human skin (skin), teeth, gums, hair, skin (skin) of non-human mammals, teeth, gums, branches or leaves, etc. Plant surfaces, etc. Figure 8 In the use methods shown in (a) to (c), the nanofiber sheet 10 is applied to the under-eye area of ​​the face, but the application location is not limited thereto.

[0124] When the nanofiber sheet 10 is used, the first surface S1 or the second surface S2 of the nanofiber layer 11 faces the surface of an object, and the nanofiber layer 11 is attached to the surface. Figure 8 As shown in (a), the first surface S1 of the nanofiber layer 11 of the nanofiber sheet 10 is attached to the skin. At this time, the surface on the base material layer 12 side is the side opposite to the skin.

[0125] When the nanofiber sheet has the above-mentioned adhesive layer, the adhesive layer is attached to the surface of the object in a direction in which the surface of the nanofiber layer 11 on the adhesive layer side faces the surface of the object. That is, when the nanofiber sheet has the adhesive layer, the nanofiber layer 11 is attached to the surface of the object via the adhesive layer 13.

[0126] Figure 8 The method of using the nanofiber sheet 10 is to attach the nanofiber layer 11 to the surface of an object, such as Figure 8 As shown in (b), the base material layer 12 is peeled off from the nanofiber layer 11. Figure 8 As shown in (c), only the nanofiber layer 11 is attached to the surface of the object.

[0127] The nanofiber layer is preferably placed in contact with the surface of an object and used in a state where the nanofiber layer is wetted by a liquid. The "wet state" means that the nanofiber layer 11 contains a liquid and is wetted.

[0128] The liquid substance refers to a substance that is liquid at 20° C. Examples of the liquid substance include liquids such as water, aqueous solutions and aqueous dispersions, colloids thickened by thickeners, oils that are liquid or solid at 20° C., oil agents containing 10% by mass or more of the oil, and emulsions containing the oil and a surfactant such as a nonionic surfactant (O / W emulsion, W / O emulsion), etc.

[0129] When the liquid material contains a polyol that is liquid at 20° C., examples of the polyol include one or more selected from ethylene glycol, propylene glycol, 1,3-butylene glycol, dipropylene glycol, polyethylene glycol having a weight average molecular weight of 2000 or less, glycerol, and diglycerol.

[0130] When the liquid substance contains an oil that is liquid at 20° C., examples of the oil include: one or more hydrocarbon oils selected from liquid paraffin, squalane, squalene, n-octane, n-heptane, cyclohexane, light isoparaffin, and liquid isoparaffin; octyldodecyl myristate, myristyl myristate, isocetyl stearate, isocetyl isostearate, stearyl isononanoate, diisobutyl adipate, di-2-ethylhexyl sebacate, isopropyl myristate, isopropyl palmitate, malic acid; Esters composed of straight-chain or branched fatty acids such as diisostearyl glycol dicaprate, benzoic acid (carbon number 12 to 15) alkyl esters, and straight-chain or branched alcohols or polyols; one or more ester oils selected from triglycerol fatty acid esters (glycerides) such as tri(caprylic acid and capric acid) glycerol; one or more silicone oils selected from dimethylpolysiloxane, dimethylcyclopolysiloxane, methylphenylpolysiloxane, methylhydrogenpolysiloxane and higher alcohol-modified organopolysiloxane, etc. These can be used alone or in combination of two or more.

[0131] When the liquid substance contains an oil that is solid at 20° C., examples of the oil include one or more selected from vaseline, cetyl alcohol, stearyl alcohol, ceramide, and the like.

[0132] As methods for using the nanofiber layer 11 in a state moistened by the liquid, for example, there are: a method (1) in which the nanofiber layer 11 is attached to the surface of an object while the surface is moistened by the liquid; a method (2) in which the nanofiber layer 11 is attached to the surface of an object while the nanofiber layer 11 is moistened by the liquid; a method (3) in which the nanofiber layer 11 is attached to the surface of an object while the nanofiber layer 11 is moistened by the liquid. After the surface of the object and the surface of the nanofiber layer 11 are brought into contact, if a liquid is applied to any of these surfaces to moisten them, the nanofiber layer 11 becomes more transparent because the nanofiber layer carries the liquid or the liquid adheres to the fiber surface of the nanofiber layer, and the peripheral edge 17 can be made less conspicuous.

[0133] In the above method (1), when the nanofiber layer 11 is brought into contact with the surface of an object wetted with a liquid substance, the liquid substance on the surface of the object can be transferred to the nanofiber layer 11 by the capillary force of the nanofiber layer 11 .

[0134] In any of the above methods (1) to (3), in order to make the surface of the object or the nanofiber layer 11 attached to the surface of the object wet with a liquid, the liquid can be applied or sprayed onto the surface. As the liquid to be applied or sprayed, a substance containing a liquid component at the temperature at which the nanofiber sheet 10 is attached and having a viscosity at this temperature (viscosity measured using an E-type viscometer) of about 5000 mPa·s or less can be used. As such a liquid, for example, water, aqueous solution, ester oil that is liquid at 20°C, hydrocarbon oil, silicone oil, glycerin and propylene glycol and other polyols that are liquid at 20°C, and aqueous dispersions containing one or more of these can be cited. In addition, emulsions such as O / W emulsions, aqueous liquids thickened by various thickeners headed by thickening polysaccharides, etc. can also be used as liquids.

[0135] The method of using the nanofiber sheet of this embodiment is to attach the nanofiber layer 11 to the surface of an object as described above. This method of use is to attach the nanofiber layer 11 to the surface of an object to improve the appearance or surface condition of the object. For example, when the object is skin, by attaching the nanofiber layer 11 to the skin, the spots or wrinkles on the skin can be concealed, thereby improving the appearance of the skin. In addition, by attaching the nanofiber layer 11 to the skin, the makeup property of the foundation, that is, the degree of application of the foundation, is improved, thereby improving the surface condition of the skin.

[0136] Next, a method for producing a nanofiber sheet of the present invention will be described with reference to the drawings according to a preferred embodiment. Fig. 9 Overview Figure 1 One embodiment (first embodiment) of an electrospinning apparatus used in the method for producing a nanofiber sheet is shown. Fig. 9 The electrospinning device 100 shown in the figure comprises: a nozzle 20 for discharging a raw material liquid; a counter electrode 30 for generating an electric field between the nozzle 20; a collecting section 40 for collecting nanofibers (fibers F) generated from the raw material liquid; and a nozzle moving mechanism 50 for moving the nozzle 20. The raw material liquid refers to a solution or dispersion of a raw material resin of the nanofibers.

[0137] The electrospinning device 100 discharges a solution or dispersion of a raw material resin (hereinafter sometimes collectively referred to as "raw material liquid") from a nozzle 20, and forms a thin-diameter fiber F by electrospinning. The nozzle 20 is mounted on a nozzle moving mechanism 50 described later. The nozzle 20 is a component that discharges the raw material liquid supplied by a raw material liquid supply unit (not shown), and is connected to the raw material liquid supply unit via a raw material supply path (not shown). The raw material liquid supply unit can quantitatively supply the raw material liquid to the nozzle 20 by known means such as a pressure load device. The raw material liquid supply unit supplies the raw material liquid to the nozzle 20 continuously or intermittently.

[0138] In this embodiment, the nozzle 20 is made of a conductive material such as metal, and is electrically connected to the voltage applying unit 32. That is, the nozzle 20 can apply a positive or negative voltage.

[0139] The counter electrode 30 is a member made of a conductive material such as metal, and is arranged to face the nozzle 20. The counter electrode 30 is grounded, so that an electric field can be generated between the nozzle 20 and the counter electrode 30. In addition, the counter electrode 30 is electrically connected to a voltage applying unit 32 such as a DC high voltage power supply, and a voltage can also be applied. In this embodiment, the counter electrode 30 is also a collection unit 40 described later.

[0140] The electrospinning device 100 applies a positive voltage to the nozzle 20, or applies a negative voltage to the counter electrode 30, or performs both at the same time, thereby generating a potential difference between the nozzle 20 and the counter electrode 30. Preferably, a negative voltage may be applied to the nozzle 20, a positive voltage may be applied to the counter electrode 30, or both may be performed at the same time, thereby generating a potential difference between the nozzle 20 and the counter electrode 30. The potential difference applied between the nozzle 20 and the counter electrode 30, that is, the potential difference applied between the nozzle 20 and the collecting part 40, is preferably 1 kV or more, more preferably 10 kV or more, from the viewpoint of improving the chargeability of the raw material liquid; and is preferably 100 kV or less, more preferably 50 kV or less, from the viewpoint of preventing discharge.

[0141] The collecting part 40 is a member for collecting the fibers F generated by electrically extending the raw material liquid. In the present embodiment, the collecting part 40 is arranged to face the nozzle 20. In addition, the collecting part 40 is the counter electrode 30 described above, and is grounded or electrically connected to the voltage applying part 32, so that a voltage can be applied. That is, in the present embodiment, an electric field can be generated between the nozzle 20 and the collecting part 40.

[0142] The nozzle moving mechanism 50 is configured to move the nozzle 20 in a planar direction. The nozzle moving mechanism 50 of the present embodiment comprises: a slide 51 for holding the nozzle 20; and rails 53 and 55 respectively along the X-axis direction and the Y-axis direction; the rail 53 moves on the rail 55, and the slide 51 moves on the rail 53. The nozzle moving mechanism 50 is electrically connected to a control unit (not shown), and can move the nozzle 20 while depositing the fibers F on the collection unit 40 according to the movement trajectory data of the nozzle input to the control unit, or according to the operation signal input to the control unit by the operator via the controller. The movement trajectory data of the nozzle determined by the trajectory calculation step described later is input or can be input to the control unit. The input of the above movement trajectory data to the control unit can be input via a recording medium such as a USB memory, or can be input via a network such as the Internet or an intranet.

[0143] In this embodiment, the electrospinning device 100 includes a stage 60 made of a non-conductive material, and the collecting portion 40 of the counter electrode 30 is placed on the stage 60. The nozzle moving mechanism 50 can move the nozzle 20 in a planar direction within a range where the stage 60 is arranged.

[0144] The manufacturing method of the nanofiber sheet of this embodiment uses an electrospinning device 100 having the above-mentioned structure, and deposits the fibers F produced by the raw material liquid on the collecting part by the electrospinning method. In a state where an electric field is generated between the nozzle 20 and the counter electrode 30, the raw material liquid is supplied to the nozzle 20, and the raw material liquid is discharged from the nozzle. At this time, the electrospinning device 100 discharges the raw material liquid while moving the nozzle 20 through the nozzle moving mechanism 50. The discharged raw material liquid forms fibers F while being pulled closer by the counter electrode 30 due to electrical repulsion and repeated evaporation of the solvent contained in the raw material liquid, and is spun. The above-mentioned nanofibers are deposited in the collecting part 40 which also belongs to the counter electrode 30, forming a deposit of nanofibers (fibers F). This deposit becomes the nanofiber layer 11.

[0145] When the thickness of the nanofiber layer 11 is large in the inner area M and the thickness of the gradual change area G gradually increases in a single direction as described above, it is preferable to deposit the fibers F while moving the nozzle 20 in the planar direction, and it is more preferable to deposit the fibers F while moving the nozzle 20 in the planar direction so that the nozzle 20 draws a predetermined circumferential track. For example, the fibers F may be deposited while the nozzle 20 is moved so as to draw a track that partially repeats the deposition position of the fibers F; or the fibers F may be deposited while the deposition time or deposition amount of the fibers F is made different at each deposition position by moving the nozzle 20. Thus, the deposition amount of the fibers F may be made partially different, and a gradual change area G having a deposition amount distribution in which the deposition amount of the fibers F gradually increases in a single direction may be formed. In particular, from the viewpoint of efficiently forming the gradual change area G, it is preferable to deposit the fibers F while moving the nozzle 20 so as to make the deposition time of the fibers F different at each deposition position. In addition, the counter electrode 30 may be moved in the planar direction instead of the nozzle 20.

[0146] The following describes in detail a method for producing a nanofiber sheet by depositing the fibers F while moving the nozzle 20 according to a preferred embodiment.

[0147] In the method for producing the nanofiber sheet of the present embodiment, as described above, the nozzle 20 is moved while the nanofibers (fibers F) are deposited on the collecting portion 40. For example, if the nozzle 20 is moved along the top view of the nanofiber sheet 10, as shown in FIG. Fig.10As shown in FIG. 2A , a first accumulation region e1 consisting of a linear nanofiber accumulation body is formed along the top view shape. The nanofibers discharged from the nozzle tend to accumulate more on the center side than on the outer edge side of the discharge hole of the nozzle 20, so the accumulation body of the nanofibers formed along the moving track of the nozzle 20 forms a region at its outer edge where the thickness gradually increases from the outer edge to the center (see FIG. 2B ). Fig.10 (b)). That is, by the method for producing a nanofiber sheet of this embodiment, a nanofiber sheet having a gradient region can be produced.

[0148] Furthermore, when the nanofiber deposit is formed while the nozzle 20 is moved, the nanofibers are deposited along the moving track of the nozzle 20, so the top view shape of the nanofiber deposit becomes a shape along the moving track of the nozzle 20. Thus, the nanofiber layer 11 of a desired top view shape can be easily formed.

[0149] In this embodiment, the fibers F are deposited on the collecting part 40 while the nozzle 20 is moved. However, the method for manufacturing a nanofiber sheet of the present invention may also move the collecting part 40 for depositing the fibers F, or may also move both the nozzle 20 and the collecting part 40. When the nanofiber layer is formed by moving both the nozzle 20 and the collecting part 40, there is an advantage that the shape of the nanofiber layer can be easily adjusted to an arbitrary shape. In this way, the method for manufacturing a nanofiber sheet of the present invention deposits the fibers F on the collecting part 40 while at least one of the nozzle 20 and the collecting part 40 is moved.

[0150] As a moving mechanism for moving the collecting section 40, for example, there can be cited: a table having a surface of the collecting section 40 opposite to the surface on which the nanofibers are deposited, and a plurality of motors for moving the table in a planar direction; or a collecting section moving mechanism 80 of the electrospinning device 100A described later.

[0151] The method for manufacturing a nanofiber sheet of the present invention forms a deposit of nanofibers while moving at least one of the nozzle 20 and the collecting part 40. Therefore, the discharge speed of the raw material liquid from the nozzle 20 or the moving speed of at least one of the nozzle 20 and the collecting part 40 will affect the thickness of the deposited nanofibers. Therefore, the method for manufacturing a nanofiber sheet of the present embodiment includes: a trajectory calculation step for determining the moving trajectory of the nozzle 20; and a deposition step for depositing the nanofibers according to the moving trajectory. As a result, the thickness of the nanofiber layer can be controlled with high precision, and the gradient region G can be formed more reliably.

[0152] In the above-mentioned trajectory calculation step, the moving trajectory of the nozzle 20 is determined based on the factors related to the stacking distribution of the nanofibers and the correlation between the thickness of the deposited nanofibers. The above-mentioned moving trajectory is to form a specified nanofiber sheet. The so-called specified nanofiber sheet refers to a sheet having a gradient region G, a specified top view shape and a specified thickness. The specified thickness is a set value determined by the product specifications, etc., and can be the minimum thickness of the nanofiber layer 11, or the maximum thickness, or the minimum thickness or maximum thickness of the gradient region G. From the perspective of covering wrinkles and spots and making it easy for functional agents such as beauty serums to penetrate into the skin, in the case where the nanofiber sheet has an inner square region M, it is preferred to set the minimum thickness D5 of the inner square region M to the specified thickness of the nanofiber sheet; in the case where the nanofiber sheet does not have an inner square region M, it is preferred to set the thickness D3 of the maximum thickness portion 15 of the gradient region G to the specified thickness of the nanofiber sheet. In the present embodiment, the movement trajectory of the nozzle 20 is determined in the trajectory calculation step. However, the movement trajectory of either or both of the nozzle 20 and the collecting unit 40 may be determined in the trajectory calculation step.

[0153] The accumulation distribution of nanofibers is the distribution of the accumulation amount of nanofibers accumulated on the collecting section 40. As the relevant factors of the accumulation distribution of nanofibers, for example, the moving speed of the nozzle 20 or the collecting section 40, the discharge speed of the raw material liquid, the potential difference between the nozzle 20 and the counter electrode 30, the distance between the nozzle 20 and the collecting section 40, the inner diameter of the nozzle 20 and the material of the nozzle can be cited, and one or a combination of two or more of these can be selected. By adjusting the values ​​of the above-mentioned factors, the thickness of the nanofiber layer can be increased or decreased. Among the relevant factors of the accumulation distribution of nanofibers, the material of the nozzle is a factor that affects the charge amount of the nozzle 20.

[0154] The trajectory calculation step is described by taking the case where the moving speed of the nozzle 20 (hereinafter also referred to as factor a), the discharge speed of the raw material liquid (hereinafter also referred to as factor b), and the distance between the nozzle 20 and the collecting part 40 (hereinafter also referred to as factor c) as the factors related to the accumulation distribution of the nanofibers as an example. The accumulation amount of the nanofibers per unit area increases or decreases by the moving speed of the nozzle 20 (factor a) or the discharge speed of the raw material liquid (factor b), and the thickness of the accumulated nanofibers increases or decreases accordingly. In addition, the area of ​​the accumulation of the nanofibers per unit time increases or decreases by the distance between the nozzle 20 and the collecting part 40 (factor c). In this way, the above factors a to c are factors that change the accumulation distribution of the nanofibers.

[0155] In the trajectory calculation step, the correlation between the above factors a to c and the thickness of the nanofiber deposit is obtained. The above correlation is obtained by setting the factors related to the deposit distribution of the nanofibers to predetermined values, making a nanofiber test body while moving the nozzle 20 on the predetermined trajectory, and measuring the thickness distribution of the test body. For example, after setting the above factors a to c to predetermined values, Fig.10 As shown, while the nozzle 20 is moved in a single direction, a test body of the nanofiber is made, and for the test body, thickness data in a cross section in a direction perpendicular to the direction in which it extends are obtained (hereinafter also referred to as simulation data). Such simulation data can be measured, for example, using a laser three-dimensional shape measurement system (e.g., a combination of a measurement system EMS2002AD-3D manufactured by COMS and a displacement meter LK-2000 manufactured by KEYENCE). Based on this simulation data and the top view shape of the set nanofiber layer 11, the thickness of the nanofiber that can be formed is simulated to determine the movement trajectory. As simulation data, data in which the setting values ​​of the above-mentioned factors a to c are set to the same condition, or a plurality of data in which the setting values ​​of the factors related to the accumulation distribution of the nanofibers are different can be used.

[0156] In the above-mentioned trajectory calculation step, calculation is performed to adjust the set values ​​of the factors related to the accumulation distribution of the nanofibers (such as the above-mentioned factors a to c), or to set the repeated or non-repeated portions of the accumulation positions of the nanofibers on the moving trajectory, so that the thickness of the nanofiber sheet becomes the set value. In addition, the calculated moving trajectory becomes a trajectory along the top view shape of the nanofiber layer 11 set by the product specifications, etc., and such a trajectory can be set using software such as SEL generator (manufactured by IAI Co., Ltd.). In the moving trajectory calculation step, the calculation of the moving trajectory is repeated, that is, the simulation of the moving trajectory is repeated until a moving trajectory along the set top view shape of the nanofiber layer 11 and satisfying the condition that the thickness of the nanofiber becomes a specified value can be obtained.

[0157] The deposition step is to deposit the nanofibers while moving at least one of the nozzle 20 and the collection unit 40 according to the movement track determined in the above-mentioned trajectory calculation step. The electrospinning device 100 of this embodiment sends the movement track data determined by the trajectory calculation step to the control unit, and according to the operation signal sent by the control unit, the nozzle moving mechanism 50 is activated to move the nozzle 20 along the above-mentioned movement track. In this way, by moving at least one of the nozzle 20 and the collection unit 40 along the movement track, a nanofiber layer having a top view shape and thickness simulated in the setting of the movement track can be formed.

[0158] like Figure 2In the case where the nanofiber sheet 10 shown in FIG. 1 has an inner region M, in the trajectory calculation step, it is preferred to calculate the moving trajectory in such a way that the minimum thickness of the inner region M becomes greater than a predetermined set value. The minimum thickness D5 of the inner region M is the thickness of the smallest portion of the inner region M (see Figure 2 At this time, in the trajectory calculation step, a movement trajectory is determined in which the minimum thickness of the inner area M becomes a desired set value and the nanofiber layer 11 becomes a desired top view shape.

[0159] In order to match the set top view shape or area of ​​the nanofiber layer 11, there is a case where a portion where the nanofiber deposition position is repeated is set on the moving track of at least one of the nozzle 20 and the collecting section 40. At this time, from the viewpoint of improving the thickness accuracy of the nanofiber layer 11, the above-mentioned deposition step preferably has the following first and second steps. The first step is to move either the nozzle 20 or the collecting section 40 along the first moving track r1 in such a way that the deposition portion of the nanofibers forms a first belt-shaped deposition area e1. The second step is to move either the nozzle 20 or the collecting section 40 along the second moving track in such a way that the deposition portion of the nanofibers forms a second belt-shaped deposition area e2 that continuously repeats the first deposition area e1 or a portion of the previously formed belt-shaped deposition area in the width direction (refer to Fig.11 (a)) The deposition step may include a single or a plurality of second steps, depending on the planar shape or area of ​​the nanofiber layer 11.

[0160] The first step and the second step are described by taking the manufacturing method of the nanofiber sheet of the present embodiment as an example. The manufacturing method of the nanofiber sheet of the present embodiment comprises the first step and the second step. In the first step of the present embodiment, a first belt-shaped stacking area e1 in which nanofibers are stacked is formed. The first stacking area e1 is formed by moving either the nozzle 20 or the collecting portion 40 along the first moving track. The first stacking area, or the second belt-shaped stacking area described later, has a track direction X along the moving track, and a width direction Y orthogonal to the track direction. In the present embodiment, the first stacking area e1 is formed as a portion of the periphery of the nanofiber layer 11. In addition, the first moving track r1 is arranged so as to surround a plurality of second moving tracks r2 described later.

[0161] In the second step of this embodiment, a second band-shaped accumulation region e2 (see Fig.11(a)). The second band-shaped stacking area e2 is formed by moving either the nozzle 20 or the collecting portion 40 along the second moving track r2. The second band-shaped stacking area e2 is formed by partially overlapping the first stacking area e1 in the width direction Y and continuously overlapping along the moving track. In the present embodiment, the second band-shaped stacking area e2 is formed in the area surrounded by the first stacking area e1, and the peripheral side portion of the second band-shaped stacking area e2 in the width direction Y continuously overlaps the inner side portion of the first stacking area e1 in the track direction X (refer to Fig.11 (a) and (b)). In addition, in this embodiment, a plurality of second steps are provided, and in the movement trajectory calculation step, the inner side trajectories s1 to s3 (see Fig.12 ) is used as the second moving track r2 used in each second step. These inner side tracks s1 to s3 are moving tracks for forming the second belt-shaped deposition area, and by moving any one of the nozzle 20 and the collecting part 40 along these inner side tracks, the first to third inner deposition areas surrounded by the first deposition area are formed. Hereinafter, the area where the deposition area overlaps with other deposition areas is also referred to as an overlapping area E (refer to Fig.11 (b)) Examples of the overlapping region E include a region where the first stacking region e1 overlaps with the second band-shaped stacking region e2, or a region where the second band-shaped stacking region e2 overlaps with another band-shaped stacking region.

[0162] From the viewpoint of more surely forming the gradual change region G, the repeated region E is preferably as follows: Fig.11 As shown in (b), in the width direction Y, it is located between the midpoint f1 of the stacking area and the outer edge f2 on the side where the other stacking areas are arranged. The overlapping area E is also preferably located in the width direction Y so that the midpoint f1 of the stacking area and the midpoint f3 of the second band-shaped stacking area e2 are located within the range of the overlapping area E. The midpoints f1 and f3 of the stacking area are positions that divide the length of the band-shaped stacking area in the width direction Y into two equal parts. Fig.11 In (b), the overlapping area E is located in the width direction Y between the midpoint f1 of the first stacking area e1 and the outer edge f2 on the side where the second strip-shaped stacking area e2 is arranged. In addition, based on the same viewpoint as above, in the above-mentioned moving trajectory calculation step, it is preferred to calculate the second moving trajectory r2 by partially overlapping the second strip-shaped stacking area between the midpoint f1 of the first stacking area and the outer edge f2 on the side where the second strip-shaped stacking area is arranged, or by arranging the midpoint f1 of the stacking area and the midpoint f3 of the second strip-shaped stacking area e2 within the range of the overlapping area E. Calculation of the second moving trajectory r2 in this way will hereinafter be referred to as calculation J1. In the case where the stacking step has multiple second steps, the second moving trajectory r2 used for each second step is preferably determined by the above-mentioned calculation J1 in the above-mentioned trajectory calculation step.

[0163] Since the nanofiber layer 11 has a gradual change region G at its outer edge as described above, for the overlapping region E in the width direction where the outer edge portions of the first stacking region and the second band-shaped stacking region overlap each other, the larger the width W10 of the overlapping region E, the greater the thickness D10 of the overlapping region E; and the smaller the width W10 of the overlapping region E, the smaller the thickness D10 of the overlapping region E. That is, by adjusting the width W10 of the overlapping region E, the minimum thickness D5 of the inner region M can be adjusted. At this time, in the above-mentioned moving track calculation step, it is preferred that the width W10 of the overlapping region E is adjusted so that the thickness D10 of the overlapping region E becomes greater than a specified thickness, for example, so that it becomes greater than the minimum thickness D5 of the inner region M in design, and the second moving track r2 is calculated according to the design of the nanofiber layer 11. The calculation of the second moving track r2 in this way is also referred to as calculation J2 hereinafter. When the deposition step includes a plurality of second steps, the second movement trajectory r2 used in each second step is preferably determined by the calculation J2 in the trajectory calculation step.

[0164] The calculation J1 and the calculation J2 are used to calculate the distance between the first moving track r1 and the second moving track r2 according to the overlap degree of the deposited portions of the nanofibers (refer to Fig.11 (b)).

[0165] From the viewpoint of more reliably ensuring the minimum thickness D5 of the inner area M and enhancing the effect of shielding spots and wrinkles by attaching the nanofiber layer, the size of the overlapping area E is preferably in the following range.

[0166] The thickness D10 of the overlapping area in the width direction Y (see Fig.11 (b)) is preferably 100% or more, more preferably 125% or more, relative to the minimum thickness D5 of the inner area M; furthermore, it is preferably 250% or less, more preferably 200% or less; furthermore, it is preferably 100% or more and 250% or less, more preferably 125% or more and 200% or less. The thickness D10 of the overlapping area E in the width direction Y is the minimum thickness in the overlapping area E.

[0167] The thickness D10 of the overlapping region E (see Fig.11 (b)) is preferably 0.2 μm or more, more preferably 1 μm or more; furthermore, it is preferably 100 μm or less, more preferably 10 μm or less; furthermore, it is preferably 0.2 μm or more and 100 μm or less, more preferably 1 μm or more and 10 μm or less.

[0168] The width of the overlap region W10 (refer to Fig.11(b)), the spacing distance W11 between the midpoint of the stacking area and the midpoints of other stacking areas in the width direction Y is preferably greater than 1%, more preferably greater than 5%; in addition, it is preferably less than 90%, more preferably less than 80%; in addition, it is preferably greater than 1% and less than 90%, more preferably greater than 5% and less than 80%.

[0169] The width W10 of the overlapping region in the width direction Y (see Fig.11 (b)), preferably 1 mm or more, more preferably 4 mm or more; furthermore, preferably 80 mm or less, more preferably 60 mm or less; furthermore, preferably 1 mm or more and 80 mm or less, more preferably 4 mm or more and 60 mm or less.

[0170] The size (width and thickness) of the overlapping area E is measured by using a laser three-dimensional shape measuring system (e.g., a combination of a measuring system EMS2002AD-3D manufactured by COMS and a displacement meter LK-2000 manufactured by KEYENCE), and is set using the above-mentioned simulation data obtained by the measurement. For example, in the case where two stacking areas are assumed to overlap by a predetermined width W10 in the width direction, the thickness D10 of the overlapping area can be calculated based on the stacking distribution data obtained by scanning and measuring the two stacking areas in the width direction Y before the overlap. This calculation can also be performed using spreadsheet software.

[0171] In this embodiment, in the moving track calculation step, the inner side tracks s1 to s3 are calculated in such a manner that the inner side tracks s1 to s3 are formed within the range surrounded by the outer adjacent moving tracks. That is, in this embodiment, the first inner side track s1 is calculated within the range surrounded by the first moving track r1, the second inner side track s2 is calculated within the range surrounded by the first inner side track s1, and the third inner side track s3 is calculated within the range surrounded by the second inner side track s2 (see Fig.12 ) The moving trajectory calculation step of this embodiment calculates the inner side trajectories s1 to s3 through the above-mentioned calculations J1 and J2 and the calculation J3 described below.

[0172] The closer the inner side track is arranged to the inner side of the first stacking area e1, the more difficult it is to form a circumferential track that is similar to the top view shape of the nanofiber layer 11. In contrast, in this embodiment, the third inner side track s3 is set as a linear track extending in a single direction. In this way, the moving track calculation step preferably calculates a circumferential track or a non-circumferential track in accordance with the area or shape of the range of the setting moving track. The calculation of the second moving track r2, that is, the inner side track, in this way is also referred to as calculation J3.

[0173] In this embodiment, the calculation J3 is performed as follows.

[0174] Determine the area surrounded by the previously determined moving track. The previously determined moving track is also called the determined track h, and the area surrounded by the determined track h is also called the determined track inner area H. In calculation J3, it is determined whether a circumferential moving track (hereinafter also referred to as a similar track k) that is roughly similar to the top view shape of the nanofiber layer 11 can be derived in the determined track inner area H. The similar track k corresponds to the determined track h that forms the determined track inner area H, so when the track line that forms the similar track k can be accommodated in the determined track inner area H, it is determined that the similar track k can be derived. That is, it is determined whether the similar track k can be configured so that the corresponding parts of the determined track h and the similar track k are adjacent to each other.

[0175] In particular, in the area H within the determination track, in the portion H1 where the portions h1 and h2 of the determination track h are opposite to each other, J3 is calculated to determine whether a portion h1 of the determination track and a portion k1 of the similar track k corresponding to the portion h1 are adjacent, and at the same time, to determine whether another portion h2 of the determination track h opposite to the portion h1 of the determination track h and a portion k2 of the similar track k corresponding to the another portion h2 are adjacent. Hereinafter, in the above-mentioned opposite portions H1, a portion of the determination track will also be referred to as portion h1, and another portion of the determination track opposite to the portion h1 will also be referred to as portion h2; a portion of the similar track corresponding to the portion h1 will be referred to as portion k1, and another portion of the similar track corresponding to the portion h2 will be referred to as portion k2, (refer to Fig.13 (a)~(c)).

[0176] In the portion H1 where the portions h1 and h2 of the trajectory are opposite to each other, the trajectory is determined by, for example, Fig.14 The processing is carried out as shown. Fig.14 In the process shown, the following steps (1) to (3) are performed.

[0177] In step (1) P1, it is determined whether the following condition (1) is satisfied. If condition (1) is satisfied, step (2) P2 is performed as the next process. If condition (1) is not satisfied, it is determined that a similar orbit cannot be derived in the portion H1 where the portions h1 and h2 of the orbit h are opposite to each other (refer to Fig.13 (a)). In addition, when the condition (1) is not satisfied, it is determined that a non-circling orbit described later cannot be derived.

[0178] Condition (1): A portion k1 of the similar track k is arranged on the inner side of a portion h2 of the determined track, and another portion k2 of the similar track is also arranged on the inner side of another portion h1 of the determined track.

[0179] In step (2) P2, it is determined whether the following condition (2) is satisfied. If condition (2) is satisfied, it is determined that a similar orbit can be derived from the portion H1 where the portions h1 and h2 of the determined orbit face each other (refer to Fig.13 (b)), determine the similar orbit ( Fig.14 If condition (2) is not satisfied, step (3) P3 is performed as the next process.

[0180] Condition (2): A portion k1 of the similar track is arranged adjacent to a portion h1 of the determined track, and another portion k2 of the similar track is arranged adjacent to another portion h2 of the determined track.

[0181] As an example of an aspect that does not satisfy the above condition (2), for example, a portion k1 of the similar track is arranged adjacent to another portion h2 of the determining track, and another portion k2 of the similar track is arranged adjacent to a portion h1 of the determining track.

[0182] If the above condition (2) is not satisfied, in step (3) P3, the center line CL1 that divides the distance between the portion k1 and the other portion k2 of the similar track into two equal parts in the width direction Y is determined as the moving track. The center line CL1 is different from the similar track and is a non-circumferential track.

[0183] The calculation J3 may be repeated in accordance with the planar shape and thickness of the nanofiber sheet. From the viewpoint of improving the adjustment accuracy of the thickness of the nanofiber layer, the calculation J3 is preferably performed for each portion H1 where the portions h1 and h2 determining the trajectory face each other.

[0184] In the manufacturing method of the nanofiber sheet of the present embodiment, in the track calculation step, the first to third inner side tracks s1, s2, and s3 are calculated by the above-mentioned calculation J1, calculation J2, and calculation J3. Specifically, the interval between adjacent tracks is calculated by calculating J1 and J2, and the first to third inner side tracks s1, s2, and s3 are calculated by calculating J3 based on the interval. In this way, the manufacturing method of the nanofiber sheet can also determine the moving track by calculating J1, calculating J2, calculating J3, or a combination of two or more of these.

[0185] The method for manufacturing a nanofiber sheet of the present embodiment is to determine a plurality of moving tracks in the track calculation step, and to move the nozzle 20 along the plurality of moving tracks in the stacking step. The moving track Ob in the present embodiment is a combination of a track group that includes a plurality of circumferential tracks that are substantially similar to each other in a nested manner, and a crossing line (turnout) that connects the plurality of tracks constituting the track group to each other (see Fig.12 ).like Fig.12As shown, the track group includes: the first moving track located at the outermost side; and the first to third inner side tracks s1 to s3 located inside the first moving track; and these multiple tracks are connected to each other by a crossing line t. From the perspective of forming the gradual change area G with better accuracy, the multiple circumferential tracks constituting the track group in the moving track are preferably connected by a crossing line t. The crossing line t connects the multiple circumferential tracks, and it only needs to intersect or connect with each circumferential track.

[0186] The crossing line t can be a straight track connecting the multiple circumferential tracks constituting the track group. On the other hand, in the electrospinning device 100, from the perspective of further controlling the discharge speed of the raw material liquid, it is preferred to discharge the raw material liquid continuously. At this time, from the perspective of suppressing the excessive increase in the thickness of the nanofiber layer, the crossing line t is preferably a straight track connecting the end points of each circumferential track constituting the track group. That is, in the track calculation step, it is preferred to calculate the crossing line t in the form of a straight track connecting the end points of each circumferential track constituting the track group.

[0187] When calculating the moving track Ob, the moving track Ob may be a track moving from the outside to the inside, a track moving from the inside to the outside, or a combination of a track moving from the outside to the inside and a track moving from the inside to the outside. In addition, the moving track Ob may be composed of the same moving direction, or a combination of different moving directions. Fig.12 In the case of the moving track Ob shown in the figure, as a form of moving from the outside to the inside, for example, a form of moving in the order of the first moving track r1, the first inner side track s1, the second inner side track s2, and the third inner side track s3 can be cited. In addition, as a form of moving from the inside to the outside, for example, a form of moving in the order of the third inner side track s3, the second inner side track s2, the first inner side track s1, and the first moving track r1 can be cited.

[0188] Hereinafter, the first moving track constituting the moving track Ob will be simply referred to as r1, and the first to third inner side tracks located inside the first moving track will be simply referred to as s1 to s3, respectively.

[0189] From the viewpoint of improving the thickness accuracy of the nanofiber layer 11 and forming the gradient region G more reliably, it is preferred that in the deposition step, the nanofibers are deposited while at least one of the nozzle and the collecting portion is repeatedly moved along at least a portion of the track constituting the track group. Fig.12In the case of the moving track Ob shown, at least one of the nozzle and the collecting part repeats the movement along any one of the multiple circumferential tracks r1, s1~s3 for multiple times. At this time, after repeating the movement along the same track for multiple times, the movement along other tracks can also be performed, or the movement along each track once can also be repeated multiple times. The above-mentioned "same track" can be the circumferential tracks r1, s1, s2, or it can be the track s3 that is not circumferential. Fig.12 In the case of the moving track Ob shown, after orbiting r1 once, s1 can be repeated twice, s2 can be repeated three times, and s3 can be repeated three times. Alternatively, after moving once in each of the orbits r1 to s3, each of the orbits s1 to s3 can be moved once, and then each of the orbits s2 and s3 can be moved once.

[0190] Based on the same viewpoint as above, the trajectory calculation step calculates the number of repetitions of repeatedly moving at least one of the nozzle and the collecting portion along the same trajectory in such a way that the thickness of the nanofiber layer becomes a predetermined set value, for example, a minimum thickness D5 of the inner square region M in design. This calculation is hereinafter also referred to as calculation J4. Calculation J4 calculates the number of repetitions of movement along the trajectory for each movement trajectory in such a way that the thickness at a predetermined position in the nanofiber layer 11 becomes a set thickness, for example, a minimum thickness D5 of the inner square region M in design. Calculation J4 can be effectively used in the case where the upper limit of the thickness of the repeated region E calculated in the above calculation J2 does not become greater than the predetermined thickness in design.

[0191] In the deposition step, as described above, at least one of the nozzle and the collecting portion may be repeatedly moved along the same circumferential track, or may be moved along a plurality of circumferential tracks having substantially similar shapes.

[0192] In this embodiment, the moving track Ob is a combination of a track group and a crossing line, but it can also be Fig.15 As shown in FIG. 1 , the moving track Ob1 is a linear track that can be drawn in one stroke. A linear track that can be drawn in one stroke is composed of a continuous line, which means that the line has no repeated parts. With this structure, the discharge of the raw material liquid can be continuously performed, and the discharge of the raw material liquid can be further controlled. Examples of the linear moving track that can be drawn in one stroke include, for example, Fig.15 The vortex shape shown.

[0193] The linear movement trajectory Ob1 that can be drawn in one stroke is obtained by the movement trajectory calculation step using the calculation J1, the calculation J2, and the calculation J3. Fig.15 In the spiral movement trajectory shown, the outermost trajectory line is the first movement trajectory r1, and the trajectory lines located inner than the outermost trajectory line are the first to third inner side trajectory s1 to s3.

[0194] When calculating the linear moving track Ob1 that can be drawn in one stroke, the moving track Ob1 can be a track that moves from the outside to the inside, or a track that moves from the inside to the outside. Fig.15 When the endpoint of the first moving track r1 side of the endpoint of the moving track Ob1 shown is set to i1, and the endpoint on the third inner side track s3 side is set to i2, the moving track Ob1 can be a track that moves with i1 as the starting point and i2 as the end point, or it can be a track that moves with i2 as the starting point and i1 as the end point.

[0195] From the viewpoint of improving the thickness accuracy of the nanofiber layer 11 or forming the gradient region G more reliably, in the deposition step, it is preferred that at least one of the nozzle and the collection unit is repeatedly moved along a linear movement track Ob1 that can be drawn with one stroke. Fig.15 When the moving track Ob1 shown moves, it can take the endpoint i1 as the starting point, move from the first moving track r1 to the endpoint i2 on the side of the third inner side track s3, then move from the first inner side track s1 via the second inner side track s2 to the endpoint i2 on the side of the third inner side track s3, and then move from the second inner side track s2 to the endpoint i2 on the side of the third inner side track s3.

[0196] From the viewpoint of suppressing the deviation of the discharge area of ​​the nanofibers discharged from the discharge hole of the nozzle 20 and forming the gradual change region G with good accuracy, it is preferred to move at least one or both of the nozzle 20 and the collecting part 40 at a predetermined speed. Based on the same viewpoint as above, the moving speed of at least one of the nozzle 20 and the collecting part 40 is preferably 5 mm / second or more, more preferably 50 mm / second or more; further, preferably 1000 mm / second or less, more preferably 150 mm / second or less; further, preferably 5 mm / second or more and 1000 mm / second or less, more preferably 50 mm / second or more and 150 mm / second or less.

[0197] The nanofiber sheet 10 of this embodiment is as follows Figure 1As shown, it is provided with a substrate layer 12 and a nanofiber layer 11 containing nanofibers. The substrate layer 12 is arranged on one side of the nanofiber layer 11. The nanofiber sheet 10 provided with the substrate layer 12 can be manufactured by arranging the substrate layer 12 on the collecting portion 40 and depositing the nanofibers on the substrate layer 12. In addition, after depositing the nanofibers, from the viewpoint of making the nanofiber sheet into a desired shape or size, the method for manufacturing the nanofiber sheet preferably includes a cutting step of cutting the obtained nanofiber sheet 10, the substrate layer 12, or both. In the cutting step, for example, a cutting device including a cutting roller having a cutting blade extending in the circumferential direction formed on the circumferential surface of the roller and a supporting roller receiving the blade of the cutting roller, or a known cutting device such as an ultrasonic cutter can be used.

[0198] The cross-sectional shape of the discharge hole of the nozzle 20 is not particularly limited, and it can be formed into any shape such as a rounded plane or a shape having an acute angle. Fig. 9 As shown, when the nozzle 20 is set to a cylindrical shape, from the perspective of efficiently depositing the fibers F, the diameter of the front end of the nozzle 20, that is, the diameter of the discharge hole is preferably greater than 0.1 mm and less than 20 mm, and more preferably greater than 0.1 mm and less than 15 mm.

[0199] The supply end of the raw material liquid supply path is preferably arranged near the nozzle 20 . For example, the supply end is preferably arranged within 10 mm from the nozzle 20 .

[0200] From the perspective of easily forming the gradient region G, the distance between the front end of the nozzle 20 and the counter electrode 30 in the electrospinning device 100 is preferably set to be greater than 30 mm, more preferably greater than 50 mm, and is preferably set to be less than 350 mm, more preferably less than 300 mm.

[0201] Next, for other embodiments of the electrospinning device used in the method for producing the nanofiber sheet, refer to Figures 16 to 21 For the electrospinning apparatuses 100A, 100B, 100C, and 100D of the second to fifth embodiments described below, the differences from the electrospinning apparatus 100 of the first embodiment described above are described. Points not particularly described are the same as those of the electrospinning apparatus of the first embodiment described above, and the description of the electrospinning apparatus is appropriately applied.

[0202] Fig.16 A second embodiment of the electrospinning device is shown. Fig.16The electrospinning device 100A shown in the figure comprises: a nozzle 20 for discharging a raw material liquid; a voltage applying section 32 which is a power source for applying a voltage to the nozzle 20; a collecting section 40 for collecting fibers F (nanofibers) generated from the raw material liquid; a nozzle moving mechanism 50 for moving the nozzle 20; and a cutting section 7 for cutting the nanofiber sheet into a contour of a predetermined shape. In the present embodiment, the collecting section 40 is made of a conductive material such as a metal. The collecting section 40 is arranged to face the nozzle 20. The collecting section 40 is grounded. Thus, by applying a positive or negative voltage to the nozzle 20, an electric field is generated between the nozzle 20 and the collecting section 40.

[0203] The cutting unit 7 cuts the nanofiber sheet 10 formed on the collecting unit 40 into a contour of a predetermined shape. The cutting unit 7 is mounted on a cutting unit moving mechanism 70 described later. Examples of the cutting unit 7 include a laser processing machine that performs melting by laser irradiation, an ultrasonic cutter that performs melting by frictional heat caused by ultrasonic vibration, and the like. From the viewpoint of being able to cut into a dense and fine shape, it is preferable to use a laser processing machine.

[0204] When a laser processing machine is used as the cutting unit 7, examples of the laser used for irradiation include CO2 laser, excimer laser, argon laser, semiconductor laser, YAG laser, etc. From the perspective of efficiently cutting the nanofiber sheet, CO2 laser is preferably used. The output of the laser is preferably 1.5 W or more, more preferably 5 W or more, and preferably 150 W or less, more preferably 50 W or less. The irradiation time of the laser is preferably 1 mm / second or more, more preferably 20 mm / second or more, and preferably 1200 mm / second or less, more preferably 300 mm / second or less.

[0205] From the viewpoint of preventing the surface of the nanofiber layer facing the base material layer from being burned when the nanofiber sheet 10 is cut by irradiation with laser light, the collecting portion 40 is preferably formed of an air-permeable member.

[0206] The electrospinning device 100A includes a base 90. The base 90 may be made of a non-conductive material or a conductive material. The base 90 has a longitudinal direction that is the X-axis direction when viewed from above, and a transverse direction that is the Y-axis direction orthogonal to the X-axis direction. The main surface of the base 90 formed by the X-axis direction and the Y-axis direction faces the nozzle 20. Fig.16 As shown, the collecting portion moving mechanism 80 is placed in the center of the main surface of the base 90. In addition, the nozzle moving mechanism 50 and the cutting portion moving mechanism 70 are arranged at the peripheral edge of the base 90 at positions that do not interfere with each other.

[0207] The collection part moving mechanism 80 has an X-axis rail 84 extending in the X-axis direction and a Y-axis rail 86 extending in the Y-axis direction. A concave guide groove 83 is formed in the X-axis direction on the X-axis rail 84. A concave guide groove 85 is formed in the Y-axis direction on the Y-axis rail 86. The collection part 40 is mounted on the X-axis rail 84 in an electrically insulated state. The collection part 40 can slide freely in the X-axis direction along the guide groove 83. The X-axis rail 84 is mounted on the Y-axis rail 86 in an electrically insulated state. The X-axis rail 84 can slide freely in the Y-axis direction along the guide groove 85. The Y-axis rail 86 is mounted and fixed on the main surface of the pedestal 90 in a manner passing through the center position of the pedestal 90 in the X-axis direction. The collection surface of the collection part 40 is parallel to the main surface of the pedestal 90. According to the collection part moving mechanism 80 having the above structure, the collection part 40 can move freely in the collection surface along the X-axis direction and the Y-axis direction.

[0208] The nozzle moving mechanism 50 is configured to move the nozzle 20 at least within the range in which the collecting portion 40 moves. The nozzle moving mechanism 50 includes: a slider 51 that holds the nozzle 20; an X-axis track and a Y-axis track 53 and 55 that extend along the X-axis direction and the Y-axis direction, respectively; and a Z-axis track 52 that extends in the Z-axis direction (which is orthogonal to the X-axis direction and the Y-axis direction and belongs to the vertical direction (perpendicular direction)). The Z-axis track 52 has a guide groove 57 that is formed in a concave shape and extends along the Z-axis direction. The slider 51 is inserted into the guide groove 57 and is freely slidable in the Z-axis direction along the guide groove 57. The Y-axis track 55 has a Y-axis guide groove 56 that extends in the Y-axis direction. The X-axis track 53 has an X-axis guide groove 54 that extends in the X-axis direction. The Z-axis track 52 is mounted on the Y-axis track 55 in an electrically insulated state. The Z-axis track 52 is freely slidable in the Y-axis direction along the Y-axis guide groove 56. The Y-axis track 55 is mounted on the X-axis track 53 in an electrically insulated state. The Y-axis rail 55 is freely slidable in the X-axis direction along the X-axis guide groove 54. One end of the X-axis rail 53 is fixed to a support 59 erected on the main surface of the pedestal 90. According to the nozzle moving mechanism 50 having the above structure, the nozzle 20 can be freely moved in the X-axis direction, the Y-axis direction and the Z-axis direction.

[0209] The cutting section moving mechanism 70 is configured to move the cutting section 7 at least within the range in which the collecting section 40 moves. The cutting section moving mechanism 70 includes: a slider 71 that holds the cutting section 7; a Y-axis track 73 and an X-axis track 75 that extend along the Y-axis direction and the X-axis direction, respectively; and a Z-axis track 72 that extends in the Z-axis direction (which is orthogonal to the X-axis direction and the Y-axis direction and belongs to the vertical direction). The Z-axis track 72 has a guide groove 77 that is formed in a concave shape and extends along the Z-axis direction. The slider 71 is embedded in the guide groove 77 and slides freely in the Z-axis direction along the guide groove 77. The Y-axis track 73 has a Y-axis guide groove 74 that extends in the Y-axis direction. The X-axis track 75 has an X-axis guide groove 76 that extends in the X-axis direction. The Z-axis track 72 is installed on the Y-axis track 73 in an electrically insulated state. The Z-axis track 72 slides freely in the Y-axis direction along the Y-axis guide groove 74. The Y-axis track 73 is installed on the X-axis track 75 in an electrically insulated state. The Y-axis rail 73 is freely slidable in the X-axis direction along the X-axis guide groove 76. One end of the X-axis rail 75 is fixed to a support column 79 erected on the main surface of the pedestal 90. According to the cutting section moving mechanism 70 having the above structure, the cutting section 7 can be freely moved in the X-axis direction, the Y-axis direction and the Z-axis direction.

[0210] The collection part moving mechanism 80, the nozzle moving mechanism 50 and the cutting part moving mechanism 70 are electrically connected to the control part (not shown), and the collection part 40, the nozzle 20 and the cutting part 7 can be moved according to the data of the moving track input to the control part or the operation signal input to the control part by the operator via the controller. The data of the moving track is input or can be input to the control part. The data of the moving track can be input via a recording medium such as a USB memory, or can be input to the control part via a network such as the Internet or an intranet.

[0211] In the electrospinning device 100A of the present embodiment, the support 59 of the nozzle moving mechanism 50 and the support 79 of the cutting section moving mechanism 70 are supported by a pedestal 90 which is a common supporting member. That is, the nozzle moving mechanism 50 and the cutting section 7 are supported by a common supporting member. As a result, the electrospinning device 100A has, in a single device, a manufacturing section in which the nozzle 20 is freely moved in three axial directions by the nozzle moving mechanism 50, and the fibers F are deposited on the collecting section 40 to manufacture the nanofiber sheet 10; and a cutting section in which the cutting section 7 is freely moved in three axial directions by the cutting section moving mechanism 70, and the nanofiber sheet 10 is cut into a contour of a predetermined shape. Thus, the electrospinning device 100A of the present embodiment becomes a compact device as a whole. By making use of the advantage of compactness, the electrospinning device 100A of the present embodiment can be easily installed in, for example, a store that sells nanofiber sheets, and nanofiber sheets with a desired shape and contour can be provided on the spot according to the needs of customers.

[0212] The nozzle moving mechanism 50 and the cutting unit 7 are supported by a common supporting member, which means that the nozzle moving mechanism 50 and the cutting unit 7 are mounted on the supporting member, and when the supporting member is moved, the nozzle moving mechanism 50 and the cutting unit 7 are also moved simultaneously. Therefore, when only one of the nozzle moving mechanism 50 and the cutting unit 7 moves and the other does not move when the supporting member is moved, the nozzle moving mechanism 50 and the cutting unit 7 are not supported by a common supporting member.

[0213] A preferred embodiment of the method for manufacturing a nanofiber sheet 10 using an electrospinning device 100A is described by taking the manufacture of a nanofiber sheet having a nanofiber layer and a substrate layer as an example. First, a substrate layer is arranged on the collection section 40. According to an operation signal sent by a control section (not shown), the collection section moving mechanism 80 is actuated to move the collection section 40 to a predetermined position. Next, an electric field is generated between the nozzle 20 and the collection section 40, and a raw material liquid is supplied to the nozzle 20, and the raw material liquid is discharged from the nozzle. During the discharge of the raw material liquid, the nozzle moving mechanism 50 is actuated according to an operation signal sent by a control section (not shown) to move the nozzle 20. The solvent contained in the discharged raw material liquid evaporates before reaching the substrate layer, and fibers F are formed and pulled to the collection section 40 for spinning. The fibers F are deposited on the substrate layer arranged in the collection section 40 to form a deposit of fibers F. This deposit becomes a nanofiber layer.

[0214] Next, according to the operation signal sent by the control unit (not shown), the cutting unit moving mechanism 70 is operated to move the cutting unit 7, and the cutting unit 7 irradiates the laser to cut the nanofiber sheet 10. Thus, the nanofiber sheet 10 of the desired top view shape is formed. The cutting unit 7 is configured to cut only the nanofiber layer on the substrate layer, or only the substrate layer located outside the periphery of the deposited nanofiber layer, or the entire nanofiber sheet 10 having the substrate layer and the nanofiber layer according to the irradiation conditions of the laser.

[0215] From the viewpoint of the formability of the nanofiber sheet 10, it is preferred that at least one of the nozzle 20, the cutting unit 7, and the collecting unit 40 be moved at a predetermined speed. The preferred range of the moving speed of each part can be set to the same range as the above-mentioned "moving speed of any one of the nozzle 20 and the collecting unit 40".

[0216] The electrospinning device 100A of this embodiment is preferably entirely covered by a protective member in consideration of being installed in a storefront, etc. A transparent portion is preferably provided on a portion of the protective member. The transparent portion is preferably made of a material that easily absorbs the wavelength of the laser, such as an acrylic resin, a polycarbonate resin, or glass, from the viewpoint of attenuating the laser light that leaks accidentally.

[0217] When the entire electrospinning device 100A is covered with a guard, it is preferable to include a dust collecting and deodorizing mechanism for deodorizing the burning smell when the nanofiber sheet 10 is cut by irradiating laser light, considering the case where the device is installed in a store or the like.

[0218] Fig.17 The third embodiment of the electrospinning device is shown. The electrospinning devices of the third embodiment and the fourth and fifth embodiments described later will be described in terms of differences from the electrospinning device 100A of the second embodiment described above. Points not particularly described are the same as those of the electrospinning device of the second embodiment, and the description of the electrospinning device is appropriately applied.

[0219] The electrospinning device 100A described above includes the nozzle moving mechanism 50 and the cutting unit moving mechanism 70 separately from the nozzle moving mechanism 50 ; however, the electrospinning device 100B of the third embodiment has the cutting unit 7 attached to the nozzle moving mechanism 50 .

[0220] Fig.17 In the electrospinning device 100B shown, a collecting portion moving mechanism 80 is placed in the central portion of the pedestal 90. In addition, a nozzle moving mechanism 50 is arranged on the peripheral portion of the pedestal 90. The nozzle moving mechanism 50 of the electrospinning device 100B includes a slider 51 for holding the nozzle 20, an X-axis track 53, a Y-axis track 55, and a Z-axis track 52. The slider 51 is embedded in a guide groove 57 formed in the Z-axis track 52. The slider 51 holds the cutting portion 7 in addition to the nozzle 20. According to the nozzle moving mechanism 50, the slider 51 can move freely in the X-axis direction, the Y-axis direction, and the Z-axis direction. As a result, the nozzle 20 and the cutting portion 7 can move freely in the X-axis direction, the Y-axis direction, and the Z-axis direction.

[0221] In the electrospinning device 100B of the present embodiment, the nozzle 20 and the cutting unit 7 are supported by the slider 51 constituting the nozzle moving mechanism 50. That is, the nozzle moving mechanism 50 and the cutting unit 7 are supported by a common supporting member. As a result, the nozzle 20 and the cutting unit 7 can be freely moved in three axial directions by the nozzle moving mechanism 50. Since the electrospinning device 100B includes a manufacturing unit for manufacturing the nanofiber sheet 10 and a cutting unit for cutting the nanofiber sheet 10 into a contour of a predetermined shape in the same nozzle moving mechanism 50, the device as a whole becomes more compact.

[0222] In the method for manufacturing the nanofiber sheet 10 using the electrospinning device 100B, similarly to the electrospinning device 100A, the nozzle moving mechanism 50 is actuated according to an operation signal sent from a control unit (not shown) to move the nozzle 20, and the raw material liquid is discharged from the nozzle 20 to form a nanofiber layer on the substrate layer arranged in the collection unit 40 to manufacture the nanofiber sheet 10. Next, according to an operation signal sent from a control unit (not shown), the nozzle moving mechanism 50 is actuated to move the cutting unit 7, and the cutting unit 7 irradiates the nanofiber slice 10 with laser light to form a nanofiber sheet 10 of a desired shape.

[0223] Fig.16 The electrospinning device 100A shown above includes a collection unit moving mechanism 80 placed in the center of a pedestal 90, and a nozzle moving mechanism 50 and a cutting unit moving mechanism 70 arranged to face each other at the peripheral portion of the pedestal 90; however, the nozzle moving mechanism 50 and the collection unit moving mechanism 80 are provided, while the cutting unit moving mechanism 70 is not provided, and the cutting unit 7 is fixed to a support column erected at the peripheral portion of the pedestal 90. In this device, the nozzle moving mechanism 50 and the cutting unit 7 are supported by the pedestal 90 which is a common supporting member, and the device as a whole becomes very compact.

[0224] Next, a fourth embodiment and a fifth embodiment of the electrospinning device will be described. Fig.18 and Fig.19 The shutter unit 1 used in each electrospinning apparatus according to the fourth embodiment and the fifth embodiment is shown. Fig.18 The chuck unit 1 shown in the figure includes a storage unit 2 for storing a raw material liquid, and a nozzle 20 for discharging the raw material liquid. The chuck unit 1 further includes a supply unit 3 for supplying the raw material liquid from the storage unit 2 to the nozzle 20 .

[0225] The storage part 2 is composed of various containers such as a bag made of synthetic resin. In the case where the storage part 2 is composed of a bag, for example, Fig.18 and Fig.19 As shown in the figure, two sheets of synthetic resin films of the same shape and size can be overlapped and their peripheries can be joined liquid-tightly to form a receiving section. The receiving section 2 has an opening 4 at its periphery for filling and delivering the raw material liquid. Through the opening 4, the raw material liquid can be filled into the space of the receiving section 2, or the raw material liquid filled in the receiving section 2 can be delivered to the outside.

[0226] The nozzle 20 has a discharge hole (not shown) with a small diameter. The nozzle 20 is made of a non-conductive material, such as a synthetic resin. In the discharge hole, a conductive needle-shaped electrode (not shown) is arranged along the length direction of the discharge hole. The electrode is used to charge the raw material liquid discharged through the nozzle 20. The electrode is connected to a power supply described later. As a result, a positive or negative voltage is applied to the nozzle 20. The nozzle 20 has one end of its discharge hole directly connected to the supply part 3 of the gate part 1. The so-called direct connection means that the two are connected in a state where there is no supply pipe of other components between the nozzle 20 and the supply part 3 except these components. The other end of the discharge hole is open to the outside.

[0227] The supply portion 3 has the function of supplying the raw material liquid contained in the containing portion 2 to the nozzle 20. For this purpose, the supply portion 3 is provided with a liquid delivery mechanism (not shown) for the raw material liquid. As the liquid delivery mechanism, a known object can be used without particular limitation. For example, a gear pump can be used as the liquid delivery mechanism. The gear pump is small and can deliver the raw material liquid with high precision and quantitatively, so it is suitable for use in the present invention. The supply portion 3 is provided with a snap-fit ​​connection portion 5 for connecting to a driving source (which will be described later) for driving the liquid delivery mechanism. The snap-fit ​​connection portion 5 is engaged with a snap-fit ​​connection portion (not shown) provided by the driving source, and transmits the driving force generated by the driving source to the liquid delivery mechanism.

[0228] Supply unit 3 Fig.19 As shown, the receiving part 6 for raw material liquid is provided. The receiving part 6 has a cylindrical base 6a. The receiving part 6 further has a cylindrical liquid receiving tube 6b which is provided on the upper end of the base 6a and is made into a smaller diameter than the base 6a. Fig.19 The receiving portion 6 is opened upward in the middle. When the gate portion 1 is in use, the receiving portion 6 is inserted into the opening portion 4 provided in the receiving portion 2, so that the receiving portion 2 can be detachably installed on the supply portion 3. In more detail, when the receiving portion 6 is inserted into the opening portion 4, the front end of the liquid receiving tube 6b reaches the storage space of the raw material liquid in the receiving portion 2, and the raw material liquid can be supplied to the supply portion 3. In addition, the base 6a is liquid-tightly fitted with the opening portion 4 to maintain the combined state of the receiving portion 2 and the supply portion 3. In this way, when the receiving portion 2 is installed in the supply portion 3, the receiving portion 2 and the supply portion 3 are directly connected. The so-called direct connection refers to connecting the two in a state where there is no supply tube other than these components between the receiving portion 2 and the supply portion 3.

[0229] The gate portion 1 has the above-mentioned structure. In this embodiment, when changing the type of raw material liquid to manufacture other nanofiber sheets, it is advantageous to simply remove the receiving portion 2 and install the receiving portion 2 containing other raw material liquids. Moreover, since the nozzle 20, which is a relatively expensive component, can be reused, it is more economical. In addition, since the receiving portion 2 is directly connected to the supply portion 3, and the supply portion 3 is also directly connected to the nozzle 20, when the gate portion 1 is replaced to use other raw material liquids, it is also advantageous to simply clean the flow path of the raw material liquid in the gate portion 1.

[0230] Fig. 20 An electrospinning device 100C according to a fourth embodiment is shown. Fig. 20 The electrospinning device 100C shown in the figure has Fig.18 and Fig.19 The electrospinning device 100C has the same configuration as the electrospinning device 100A of the second embodiment except that the electrospinning device 100C has the electrospinning device 100A having the nozzle 20 and the nozzle moving mechanism 50 moves the entire electrospinning device 1 .

[0231] The nozzle moving mechanism 50 is configured to move the chuck unit 1 including the nozzle 20 within at least the range in which the collecting unit 40 moves. The nozzle moving mechanism 50 of this embodiment has the same configuration as the nozzle moving mechanism 50 of the second embodiment except for this configuration.

[0232] In the nozzle moving mechanism 50, as described above, the clamping part 1 is detachably mounted on the slide 51. That is, the slide 51 is used not only as a means for lifting and lowering the clamping part 1, but also as a mounting part of the clamping part 1. The slide 51, which is the mounting part of the clamping part 1, is provided with a supply part 3 (see Fig.18 and Fig.19 The driving source 8 is provided with a card connection portion 5 (see Fig.18 and Fig.19 ) is engaged with the engaged connection part (not shown). When the gate part 1 is mounted on the slide 51 as its mounting part, the engaging connection part 5 of the supply part 3 and the engaged connection part (not shown) of the driving source 8 are engaged, and the driving force generated by the driving source 8 is transmitted to the supply part 3.

[0233] As described above, in this embodiment, since the gate portion 1 is detachably mounted on the slider 51, when the type of raw material liquid is changed to manufacture another nanofiber sheet, there is an advantage that the nanofiber sheet can be manufactured again by simply removing the gate portion 1 from the slider 51 and then installing the gate portion 1 containing another raw material liquid. This advantage is particularly significant when the storage portion 2 in the gate portion 1 cannot be loaded and unloaded by the supply portion 3.

[0234] The shutter unit 1 is detachably mounted on the slider 51 of the mounting portion thereof and is electrically insulated. Thus, even when a high voltage is applied to the nozzle 20 of the shutter unit 1, unintentional discharge can be effectively suppressed.

[0235] The collecting section moving mechanism 80, the nozzle moving mechanism 50 and the cutting section moving mechanism 70 are electrically connected to a control section (not shown), and the collecting section 40, the gate section 1 and the cutting section 7 can be moved according to the data of the moving track input to the control section or the operation signal input to the control section by the operator via the controller.

[0236] Fig.21 An electrospinning device 100D according to a fifth embodiment is shown. Fig.21 The electrospinning device 100D shown in FIG. Fig.18 and Fig.19 In the electrospinning device 100D, the cutting unit 7 is attached to the nozzle moving mechanism 50 .

[0237] Fig.21 In the electrospinning device 100D shown, a collecting section moving mechanism 80 is placed in the central part of the base 90. In addition, a nozzle moving mechanism 50 is arranged on the peripheral part of the base 90. The nozzle moving mechanism 50 of the electrospinning device 100D includes: a slider 51 on which the gate section 1 including the nozzle 20 can be detachably mounted; rails 53, 55; and a Z-axis rail 52. The slider 51 is embedded in a guide groove 57 formed in the Z-axis rail 52. The slider 51 holds the gate section 1 and the cutting section 7. According to the nozzle moving mechanism 50, the slider 51 can move freely in the X-axis direction, the Y-axis direction, and the Z-axis direction. As a result, the gate section 1 including the nozzle 20 and the cutting section 7 can move freely in the X-axis direction, the Y-axis direction, and the Z-axis direction.

[0238] In the electrospinning device 100D of the present embodiment, the gate portion 1 including the nozzle 20 and the cutting portion 7 are supported by the slider 51 constituting the nozzle moving mechanism 50. That is, the nozzle moving mechanism 50 and the cutting portion 7 are supported by a common supporting member. As a result, the nozzle 20 and the cutting portion 7 can be freely moved in three axial directions by the nozzle moving mechanism 50. Since the electrospinning device 100D includes a manufacturing portion for manufacturing the nanofiber sheet 10 and a cutting portion for cutting the nanofiber sheet 10 into a contour of a predetermined shape in the same nozzle moving mechanism 50, the device as a whole becomes more compact.

[0239] Next, the raw material solution used in the method for producing a nanofiber sheet using the above-mentioned electrospinning device will be described.

[0240] As the raw material liquid, a solution in which a fiber-forming polymer compound is dissolved or dispersed in a solvent can be used. As the fiber-forming polymer compound, the above-mentioned nanofiber-forming polymer compound is used.

[0241] The raw material liquid may contain, in addition to the above-mentioned polymer compound, inorganic particles, organic particles, plant extracts, surfactants, oils, electrolytes for adjusting ion concentration, and the like as appropriate.

[0242] Examples of the solvent for the raw material solution include water, methanol, ethanol, 1-propanol, 2-propanol, hexafluoroisopropanol, 1-butanol, isobutyl alcohol, 2-butanol, 2-methyl-2-propanol, tetraethylene glycol, triethylene glycol, dibenzyl alcohol, 1,3-dioxolane, 1,4-dioxane, methyl ethyl ketone, methyl isobutyl ketone, methyl n-hexyl ketone, methyl n-acetone, diisopropyl ketone, diisobutyl ketone, acetone, hexafluoroacetone, phenol, formic acid, methyl formate, ethyl formate, propyl formate, methyl benzoate, ethyl benzoate, propyl benzoate, ethyl methyl phthalate, ethyl acetate, propyl acetate, dimethyl phthalate, diethyl phthalate, dipropyl phthalate, methyl chloride, ethyl chloride, dichloromethane, chloroform, o-chlorotoluene, p-chlorotoluene, carbon tetrachloride, 1,1-dichloroethane, 1,2-dichloroethane, trichloroethane, dichloropropane, dibromoethane, dibromopropane, methyl bromide, ethyl bromide, bromopropane, acetic acid, benzene, toluene, hexane, cyclohexane, cyclohexanone, cyclopentane, o-xylene, p-xylene, m-xylene, acetonitrile, tetrahydrofuran, N,N-dimethylformamide, pyridine, etc. These solvents can be used alone or in combination.

[0243] The nanofiber layer 11 is laminated directly or via an adhesive layer on a sheet-like object that becomes the base layer 12. The nanofiber layer 11 and the base layer 12 are integrated by bonding using an adhesive, pressure bonding, joining by ultrasonic sealing, melting by laser, hot melting by heat sealing, etc. In addition, when the nanofiber sheet has an adhesive layer, the nanofiber layer 11 and the base layer 12, or either or both of the base layer 12 and the adhesive layer are integrated by the above-mentioned bonding.

[0244] The nanofiber sheet can also be manufactured by changing the spinning direction of the fibers F without moving the nozzle 20 or the counter electrode 30 to form a gradual change region G where the accumulation amount of the fibers F gradually increases. For example, the nozzle 20 is provided with an air flow ejection portion for ejecting an air flow, and the fibers F are deposited by blowing air flow against the fibers F so that the accumulation position of the fibers F becomes a desired position.

[0245] The above description is about manufacturing nanofibers by electrostatic spinning, and manufacturing nanofiber sheets by depositing nanofibers on one side of a substrate layer, but the present invention can be applied to fibers other than nanofibers, such as fibers thicker than nanofibers. In addition, the present invention can also be applied to particles manufactured by electrostatic spraying and captured by a capture unit.

[0246] More specifically, the present invention includes a laminated sheet having a substrate layer and an ultra-thin sheet disposed on one side of the substrate layer. The ultra-thin sheet is preferably composed of a deposit of fibers or particles. That is, the ultra-thin sheet is preferably a fiber sheet or a film-like sheet. The fibers or particles constituting the ultra-thin sheet are produced by discharging a raw material liquid of the fibers or particles from a nozzle. In the case of producing fibers from a raw material liquid, the method is not particularly limited, and for example, a melt spinning method can be used.

[0247] The thickness of the fiber generated from the raw material solution is preferably set to 10 nm or more, more preferably 0.1 μm or more, and further preferably 0.3 μm or more. In addition, the thickness of the fiber generated from the raw material solution is preferably set to 30 μm or less, more preferably 3 μm or less, and further preferably 1 μm or less. The thickness of the fiber generated from the raw material solution is preferably 10 nm or more and 30 μm or less, more preferably 0.1 μm or more and 3 μm or less, and further preferably 0.3 μm or more and 1 μm or less.

[0248] The raw material of the fibers contained in the raw material liquid may be the same as the raw material constituting the nanofiber layer 11 described above.

[0249] On the other hand, the size of the particles is preferably, for example, 0.01 μm or more, more preferably 0.1 μm or more, and further preferably 1 μm or more. In addition, the size of the particles is preferably, for example, 200 μm or less, more preferably 100 μm or less, and further preferably 10 μm or less. The size of the particles is preferably 0.01 μm or more and 200 μm or less, more preferably 0.1 μm or more and 100 μm or less, and further preferably 1 μm or more and 10 μm or less. The size of the particles is the cumulative volume 50% volume cumulative particle size D measured by laser diffraction / scattering particle size distribution measurement. 50 Indicated.

[0250] The raw material of the particles contained in the raw material liquid may be the same as the raw material constituting the nanofibers.

[0251] The thickness of the ultra-thin sheet is preferably 5.1 μm or more, more preferably 10 μm or more, regardless of whether it is composed of a deposit of fibers or a deposit of particles. In addition, the thickness of the ultra-thin sheet is preferably 500 μm or less, more preferably 400 μm or less. The thickness of the ultra-thin sheet is preferably 5.1 μm or more and 500 μm or less, more preferably 10 μm or more and 400 μm or less.

[0252] In the laminated sheet, the substrate layer and the ultra-thin sheet are laminated in a releasable manner. The laminated sheet preferably has an adhesive layer, similar to the nanofiber sheet 10. The adhesive layer is preferably disposed between the substrate layer and the ultra-thin sheet, or on the surface of the ultra-thin sheet opposite to the substrate layer.

[0253] The ultra-thin sheet preferably has a contour shape that matches the application site to which the ultra-thin sheet is applied. The application site to which the ultra-thin sheet is applied is not particularly limited, and similarly to the nanofiber sheet 10, examples thereof include surface sites of the human body (i.e., skin), teeth, gums, hair, skin (skin) of non-human mammals, teeth, gums, plant surfaces such as branches or leaves, etc., but are not limited to these application sites.

[0254] When the ultra-thin sheet is applied to a surface part of a human body, for example, it is preferable to form the ultra-thin sheet in a shape that matches the intended use or the shape that matches the surface part. For example, when the ultra-thin sheet is applied to the area under the eyes, the ultra-thin sheet is preferably formed in such a way that it has a contour shape that matches the intended use or the contour shape that matches the surface part. Figure 1 In the embodiment of the present invention, an oblong profile with a curved portion is used as shown. From the same point of view, when the ultra-thin sheet is applied to the cheek, a triangular profile with rounded corners and / or curved sides facing outward is preferably used as the ultra-thin sheet. Furthermore, from the same point of view, when the ultra-thin sheet is applied to the forehead, a substantially elliptical profile is preferably used as the ultra-thin sheet. In addition, when the ultra-thin sheet is used for correction of spots or moles on the surface of the human body or uneven skin color, a circular, elliptical, rounded quadrilateral or a combination of the above shapes can be used.

[0255] Regardless of the contour shape of the ultra-thin sheet, from the viewpoint of improving the conformability between the ultra-thin sheet and the part to which the ultra-thin sheet is applied, the contour line of the ultra-thin sheet is preferably composed of a curve for more than half of the total length of the contour line. From the viewpoint of making this advantage more significant, the contour line of the ultra-thin sheet is preferably composed of a curve for more than 60%, more preferably more than 70%, and more preferably more than 80% of the total length of the contour line. The contour line of the ultra-thin sheet may also be composed entirely of lines. Such a contour line can be determined by the top view contour curve in the above-mentioned (method for measuring the thickness of the peripheral end).

[0256] The ultra-thin sheet has a tapered peripheral region whose thickness gradually increases from its peripheral end toward the inner direction. The so-called "tapered" refers to the cross-sectional shape of the peripheral region of the ultra-thin sheet when viewed along its thickness direction. The "tapered peripheral region" has the same meaning as the above-mentioned "gradual change region G".

[0257] The tapered peripheral region is preferably formed in an area within 5 mm in width from the peripheral portion of the ultra-thin sheet. The so-called "width of the tapered peripheral region" has the same meaning as the width W1 of the gradient region G in the nanofiber sheet described previously. The width of the tapered peripheral region may be the same at any point in the peripheral region, or may differ depending on the position. In the case where the width of the tapered peripheral region differs depending on the position, the minimum width is preferably within 5 mm.

[0258] The ultra-thin sheet has an inner area surrounded by the peripheral area at a position more inward than the tapered peripheral area. The inner area is different from the peripheral area, and its thickness is essentially a certain area. When referring to the thickness of the ultra-thin sheet, it means the thickness in the inner area. The thickness of the inner area, that is, the thickness of the ultra-thin sheet is preferably set to 5.1μm or more, more preferably 10μm or more. In addition, the thickness of the ultra-thin sheet is preferably set to 500μm or less, more preferably 400μm or less. The thickness of the ultra-thin sheet is preferably set to 5.1μm or more and 500μm or less, more preferably 10μm or more and 400μm or less.

[0259] As described above, the inner area is an area with substantially constant thickness. Therefore, the thickness of the inner area is allowed to vary slightly depending on the position. For example, the thickness is allowed to vary within a range of about ±25% relative to the average thickness.

[0260] In the cross section along the thickness direction of the ultra-thin sheet, the width of the inner square region is preferably 100 mm or less, more preferably 50 mm or less, and further preferably 30 mm or less. The minimum value of the width of the inner square region is preferably 0 mm, that is, the inner square region may not exist. The so-called "width of the inner square region" is the same as the "width W2 of the inner square region M" in the nanofiber sheet of the previous specification (refer to Figure 2 ) has the same meaning.

[0261] The thickness of the inner square region and the thickness of the peripheral region in the ultra-thin sheet can be measured according to the previously described (Method for measuring the three-dimensional shape of the nanofiber layer). This measurement method can also be applied to the measurement of the thickness of the gradient region G and the thickness of the inner square region M in the previously described nanofiber sheet.

[0262] The base layer in the laminated sheet preferably has a region extending outward from the peripheral edge of the ultra-thin sheet (this region is sometimes referred to as an "extended region"). Figures 1 to 3 As shown, the same is true when the base layer 12 has a region extending outward from the peripheral edge of the nanofiber layer 11. When the base layer has the extending region in the laminated sheet, it is easy to peel the ultra-thin sheet from the base layer.

[0263] The substrate layer in the laminated sheet can extend from the entire area of ​​the peripheral end of the ultra-thin sheet, or it can extend from a part of the peripheral area. In either case, the extent of extension of the extended area can be different or the same depending on the position. When the substrate layer extends from the entire area of ​​the peripheral end of the ultra-thin sheet, and the extent of extension of the extended area is not the same depending on the position, the contour shape of the ultra-thin sheet and the contour shape of the substrate layer become roughly similar. The advantages of the contour shapes of the two being similar are as follows. The thickness of the ultra-thin sheet is sometimes very thin and cannot be easily visually observed. In contrast, if the contour shape of the ultra-thin sheet and the contour shape of the substrate layer are roughly similar, the contour shape of the substrate layer that is easily visually observed can be seen, and the presence of the ultra-thin sheet and the peeling off of the substrate sheet can be easily confirmed.

[0264] The present invention can be applied to a method for producing an ultra-thin sheet having a thickness of 5.1 μm to 500 μm by discharging a raw material liquid from a nozzle and depositing fibers or particles generated from the raw material liquid on a collecting portion.

[0265] Furthermore, the present invention can be applied to a method for manufacturing an ultra-thin sheet having a thickness of 5.1 μm to 500 μm by discharging a raw material liquid from a nozzle and depositing particles generated from the raw material liquid on a substrate on a collecting portion.

[0266] The above descriptions of the fibers or particles generated from the raw material solution can be applied to the manufacturing methods of these ultra-thin sheets. In addition, the descriptions of the above ultra-thin sheets can be appropriately applied to the ultra-thin sheets obtained by these manufacturing methods.

[0267] The method for manufacturing an ultra-thin sheet includes a target shape forming step. In the target shape forming step, similarly to the method for manufacturing a nanofiber sheet, based on information on the contour shape of the target ultra-thin sheet, at least one of the nozzle and the collecting portion is moved while the raw material liquid is discharged within the contour shape of the ultra-thin sheet. The positional relationship between the nozzle and the collecting portion is, for example, the same as that described above. Fig. 9 The driving mechanism of the nozzle and the collecting part is also the same as Fig. 9 The embodiments shown are identical.

[0268] In the target shape forming step, the raw material liquid is discharged in such a manner that a tapered peripheral region whose thickness gradually increases from the peripheral end of the target ultra-thin sheet contour toward the inner direction is formed. This "taper" also refers to the cross-sectional shape of the peripheral region when the ultra-thin sheet is viewed along its thickness direction. That is, the "tapered peripheral region" has the same meaning as the above-mentioned "gradual change region G", and the above description can be appropriately applied.

[0269] As mentioned above, although this invention was demonstrated based on the preferred embodiment, this invention is not limited to the said embodiment, It can change suitably.

[0270] For example, in the electrospinning device 100 of the above embodiment, the collecting unit 40 is the counter electrode 30, but the collecting unit 40 and the counter electrode 30 may be separate members. In this case, the collecting unit 40 and the counter electrode 30 may be arranged adjacent to each other.

[0271] Furthermore, the nanofiber sheet 10 of the above embodiment includes the base layer 12 , but may not include the base layer 12 .

[0272] Furthermore, in the above-mentioned embodiment, in the trajectory calculation step, the moving speed of the nozzle 20, the discharge speed of the raw material liquid, and the distance between the nozzle 20 and the collecting section 40 are used as factors related to the stacking distribution of the nanofibers, but factors other than these may also be used, or these and other factors may be combined and used.

[0273] In addition, in each embodiment of the electrospinning device described above, the slider 51, which is a mounting portion of the nozzle 20 or the gate portion 1, is mounted on a three-axis moving mechanism, but it can also be replaced by being mounted on a moving mechanism of at least one axis. Similarly, the collecting portion 40 and the slider 71 can also be mounted on a moving mechanism of at least one axis.

[0274] Furthermore, although the base 90 in the apparatus of each of the above-mentioned embodiments is constituted by a single member, two or more members may be connected by any connecting means or fastening means to form a substantially single member.

[0275] In addition, the apparatus of each of the above-mentioned embodiments is provided with the nozzle moving mechanism 50, but the nozzle moving mechanism 50 may not be used, and the nozzle 20 or the clamping part 1 including the nozzle 20 may be fixed immovably on another supporting member in the apparatus. The apparatus of this embodiment must at least have the collecting part moving mechanism 80. As an apparatus for fixing the nozzle 20 immovably, for example, there can be cited an apparatus including a pedestal 90 arranged opposite to the nozzle 20, the collecting part moving mechanism 80 placed on the center of the pedestal 90, and the cutting part moving mechanism 70 arranged on the peripheral part of the pedestal 90, wherein the collecting part moving mechanism 80 and the cutting part moving mechanism 70 are supported by the pedestal 90 which is a common supporting member. The apparatus of this kind is also very compact as a whole. In addition, as a device for fixing the nozzle 20 in an immovable manner, for example, there can be cited: a device including a base 90 arranged opposite to the nozzle 20, a collecting portion moving mechanism 80 mounted on the central part of the base 90, and a cutting portion 7 immovably fixed to a support column erected on the peripheral part of the base 90, and the collecting portion moving mechanism 80 and the cutting portion 7 are supported by the base 90 which is a common supporting member.

[0276] Fig.16 The electrospinning device 100A of the embodiment shown, and Fig. 20 The electrospinning device 100C of the illustrated embodiment includes a collection unit moving mechanism 80 placed in the center of a pedestal 90, and a nozzle moving mechanism 50 and a cutting unit moving mechanism 70 arranged to face each other at the peripheral portion of the pedestal 90. However, the electrospinning device may be configured to include a nozzle moving mechanism 50 but not include a collection unit moving mechanism 80, and to fix the collection unit 40 to the center of the pedestal 90. In addition, the electrospinning device may be configured to include a collection unit moving mechanism 80 but not include a cutting unit moving mechanism 70, and to fix the cutting unit 7 to a support column erected at the peripheral portion of the pedestal 90. In these devices, the nozzle moving mechanism 50 and the cutting unit 7 are supported by the pedestal 90, which is a common supporting member, and the device as a whole is very compact.

[0277] Fig.17 The electrospinning device 100B of the embodiment shown, and Fig.21The electrospinning device 100D of the embodiment shown is provided with a collection part moving mechanism 80 placed in the center of a pedestal 90, and a nozzle moving mechanism 50 arranged at the peripheral portion of the pedestal 90, and the nozzle moving mechanism 50 is installed with the nozzle 20 or the gate part 1 and the cutting part 7 containing it; however, it is also possible to construct an electrospinning device having a nozzle moving mechanism 50 but not having a collection part moving mechanism 80, and fixing the collection part 40 to the center of the pedestal 90. In such a device, the nozzle 20 and the cutting part 7 are supported by the nozzle moving mechanism 50 which is a common supporting member, and the device as a whole is very compact. In addition, it is also possible to construct a device having a collection part moving mechanism 80 but not having a cutting part moving mechanism 70, and fixing the nozzle 20 and the cutting part 7 to a pillar erected at the peripheral portion of the pedestal 90. In such a device, the nozzle moving mechanism 50 and the cutting part 7 are supported by the pedestal 90 which is a common supporting member, and the device as a whole is very compact.

[0278] Furthermore, the electrospinning apparatus of each embodiment described above includes a voltage applying unit 32 that is a power source and applies a voltage to the nozzle 20, but as described in Japanese Patent Laid-Open No. 2017-31517, the electrospinning apparatus may also include: a raw material ejecting unit having a nozzle; a counter electrode that is arranged to be opposite to the nozzle and has a concave surface that generates an electric field between the nozzle; and a voltage generating unit that is a power source and applies a voltage between the nozzle and the counter electrode. According to the apparatus described in the same publication, nanofibers can be deposited on a substrate layer arranged in the collection unit while blowing air flow toward the collection unit.

[0279] Regarding the above-mentioned embodiments, the present invention further discloses the following nanofiber sheets, methods of using the same, methods of manufacturing the same, and methods of manufacturing the nanofiber sheets.

[0280] <1> A nanofiber sheet comprising a substrate layer and a nanofiber layer containing nanofibers of a polymer compound disposed on one side of the substrate layer;

[0281] The thickness of the nanofiber layer at the peripheral edge is not less than 0.1 μm and not more than 10 μm, and has a gradual change region of not less than 3 mm in thickness, where the thickness gradually increases from the peripheral edge toward the inside.

[0282] <2> A laminated sheet comprising a substrate layer and an ultra-thin sheet having a thickness of 5.1 μm or more and 500 μm or less and arranged on one side of the substrate layer;

[0283] The ultra-thin sheet has a contour shape that matches the part to which the ultra-thin sheet is applied;

[0284] The ultra-thin sheet has a tapered peripheral region whose thickness gradually increases from its peripheral end toward the inside;

[0285] The base layer has a region extending outward from the peripheral edge of the ultra-thin sheet.

[0286] <3> As mentioned above <1> The nanofiber sheet or the above <2> A laminated sheet, wherein the thickness of the peripheral edge is greater than 0.3 μm, preferably greater than 0.5 μm; furthermore, is less than 9 μm, preferably less than 8 μm; furthermore, is greater than 0.3 μm and less than 9 μm, preferably greater than 0.5 μm and less than 8 μm.

[0287] <4> As mentioned above <1> ~ <3> The nanofiber sheet or laminated sheet described in any one of the above-mentioned gradient region or the above-mentioned tapered peripheral region, wherein the thickness D3 of the maximum thickness portion belonging to the inner end is greater than 5.1 μm, preferably greater than 10 μm; furthermore, is less than 500 μm, preferably less than 400 μm; furthermore, is greater than 5.1 μm and less than 500 μm, preferably greater than 10 μm and less than 400 μm.

[0288] <5> As mentioned above <1> ~ <4> The nanofiber sheet or laminated sheet described in any one of the above-mentioned embodiments, wherein the inclination angle of the above-mentioned gradient area or the above-mentioned tapered peripheral area is greater than 0.001°, preferably greater than 0.002°; furthermore, it is less than 10°, preferably less than 8°; furthermore, it is greater than 0.001° and less than 10°, preferably greater than 0.002° and less than 8°.

[0289] <6> As mentioned above <1> ~ <5> The nanofiber sheet or laminated sheet according to any one of the above-mentioned embodiments, wherein in the above-mentioned gradual change region or the above-mentioned tapered peripheral region, the difference in thickness between the inner end and the above-mentioned peripheral end is 5 μm or more.

[0290] <7> As mentioned above <1> ~ <6> The nanofiber sheet or laminated sheet described in any one of the above-mentioned embodiments, wherein, in the above-mentioned gradient region or the above-mentioned tapered peripheral region, the thickness difference between the maximum thickness portion of the inner end and the above-mentioned peripheral end is 5 μm or more, preferably 10 μm or more; further, it is 500 μm or less, preferably 400 μm or less; further, it is 5 μm or more and 500 μm or less, preferably 10 μm or more and 400 μm or less.

[0291] <8> As mentioned above <1> ~ <7> The nanofiber sheet or laminated sheet described in any one of the above-mentioned descriptions, wherein, in the above-mentioned gradient region or the above-mentioned tapered peripheral region, the ratio (D3 / D1) of the thickness D3 of the above-mentioned maximum thickness portion at the inner end to the thickness D1 of the above-mentioned peripheral end is 50 or more, preferably 100 or more; further, it is 5000 or less, preferably 4000 or less; further, it is 50 or more and 5000 or less, preferably 100 or more and 4000 or less.

[0292] <9> As mentioned above <1> ~ <8> The nanofiber sheet or laminated sheet described in any one of the above, wherein the top view shape of the above-mentioned nanofiber layer or the above-mentioned ultra-thin sheet is a shape that includes multiple curved parts with different curvatures in its outline, a shape that includes multiple straight parts in its outline, or a shape that includes the curved parts and the straight parts in its outline.

[0293] <10> As mentioned above <1> ~ <9> The nanofiber sheet or laminated sheet described in any one of the above, wherein the nanofiber layer or the ultra-thin sheet is disposed adjacent to the substrate layer, and the substrate layer has air permeability.

[0294] <11> As mentioned above <1> ~ <10> The nanofiber sheet or laminated sheet described in any one of the preceding claims, wherein the substrate layer is a nonwoven fabric.

[0295] <12> As mentioned above <1> ~ <10> The nanofiber sheet or laminated sheet according to any one of the preceding claims, wherein the substrate layer is a sponge.

[0296] <13> As mentioned above <1> ~ <12> The nanofiber sheet or laminated sheet described in any one of the above, wherein the above-mentioned nanofiber layer or the above-mentioned ultra-thin sheet is arranged adjacent to the above-mentioned substrate layer, and the above-mentioned substrate layer has a plurality of recessed or convex portions with a width greater than the fiber diameter of the nanofiber on the surface opposite to the nanofiber layer or the ultra-thin sheet.

[0297] <14> As mentioned above <1> ~ <13> The nanofiber sheet or laminated sheet according to any one of the preceding claims, wherein the nanofiber layer or the ultra-thin sheet is water-insoluble.

[0298] <15> As mentioned above <14> The nanofiber sheet or laminated sheet, wherein the water-insoluble polymer contained in the nanofiber layer or the ultra-thin sheet exceeds 50% by mass, preferably 80% by mass or more; the water-soluble polymer contained in the nanofiber layer or the ultra-thin sheet is preferably less than 50% by mass, more preferably less than 20% by mass.

[0299] <16> As mentioned above <1> ~ <15> The nanofiber sheet or laminated sheet according to any one of the preceding claims, wherein the nanofiber layer or the ultra-thin sheet contains other components in addition to the nanofibers, and the content of the nanofibers in the nanofiber layer or the ultra-thin sheet is 40% by mass or more and 95% by mass or less, preferably 70% by mass or more and 90% by mass or less;

[0300] The content of other components in the nanofiber layer or the ultrathin sheet is 5% by mass or more and 60% by mass or less, preferably 10% by mass or more and 30% by mass or less.

[0301] <17> As mentioned above <1> ~ <16> The nanofiber sheet or laminated sheet described in any one of the preceding claims, wherein the nanofiber layer or the ultra-thin sheet has an inner square region surrounded by the gradient region or the tapered peripheral region, and the inner square region has a concave portion;

[0302] The thickness in the above-mentioned recessed portion in the above-mentioned inner square area is 50% or more, preferably 60% or more, relative to the thickness of the above-mentioned maximum thickness portion; further, it is 100% or less, preferably 90% or less; further, it is 50% or more and 100% or less, preferably 60% or more and 90% or less.

[0303] <18> As mentioned above <17> A nanofiber sheet or a laminated sheet, wherein the thickness of the above-mentioned recessed portion in the above-mentioned inner square region is greater than 5.1 μm, preferably greater than 10 μm; furthermore, it is less than 500 μm, preferably less than 400 μm; furthermore, it is greater than 5.1 μm and less than 500 μm, preferably greater than 10 μm and less than 400 μm.

[0304] <19> As mentioned above <17> or <18> A nanofiber sheet or a laminated sheet, wherein the inner square region includes as the concave portion: a shallow concave portion having a greater thickness than the maximum thickness portion at the inner square end in the gradient region or the tapered peripheral region; and a deep concave portion having a smaller thickness than the maximum thickness portion;

[0305] The thickness of the shallow recess in the inner area is 5.1 μm or more, preferably 10 μm or more, and 500 μm or less, preferably 400 μm or less; furthermore, 5.1 μm or more and 500 μm or less, preferably 10 μm or more and 400 μm or less.

[0306] <20> As mentioned above <19> A nanofiber sheet or a laminated sheet, wherein the thickness of the deep recess is greater than 5.1 μm, preferably greater than 10 μm; furthermore, it is less than 500 μm, preferably less than 400 μm; furthermore, it is greater than 5.1 μm and less than 500 μm, preferably greater than 10 μm and less than 400 μm.

[0307] <21> As mentioned above <1> ~ <20> The nanofiber sheet or laminated sheet according to any one of the preceding claims, comprising an adhesive layer that can be attached to a surface of an object;

[0308] The adhesive layer is disposed between the substrate layer and the nanofiber layer or the ultra-thin sheet, or on a surface of the nanofiber layer or the ultra-thin sheet opposite to the substrate layer.

[0309] <22> As mentioned above <2> ~ <21> The laminated sheet according to any one of the preceding claims, wherein the ultra-thin sheet is formed of a nanofiber layer comprising nanofibers of a polymer compound.

[0310] <23> As mentioned above <2> ~ <22> The laminated sheet according to any one of the above aspects, wherein the thickness of the peripheral edge of the ultra-thin sheet is 0.1 μm or more and 10 μm or less.

[0311] <24> As mentioned above <2> ~ <23> The laminated sheet according to any one of the preceding claims, wherein the tapered peripheral region is formed in a region within a width of 5 mm inward from the peripheral edge of the ultra-thin sheet.

[0312] <25> As mentioned above <2> ~ <24> The laminated sheet according to any one of the above-mentioned embodiments, wherein, in the outline of the ultra-thin sheet, a portion of more than half of the entire length of the outline is composed of a curve.

[0313] <26> A method for using a nanofiber sheet or a laminated sheet, the above <1> ~ <25> The method for using the nanofiber sheet or laminated sheet according to any one of the preceding claims,

[0314] The nanofiber layer or the ultra-thin sheet is placed in contact with the surface of an object and is used in a wet state.

[0315] <27> As mentioned above <26> A method for using a nanofiber sheet or a laminated sheet, wherein the nanofiber layer or the ultra-thin sheet is attached to the surface of an object in a wet state.

[0316] <28> As mentioned above <26> A method for using a nanofiber sheet or a laminated sheet, wherein the nanofiber layer or the ultra-thin sheet is wetted in a state where the nanofiber layer or the ultra-thin sheet is attached to the surface of an object.

[0317] <29> As mentioned above <26> A method for using a nanofiber sheet or a laminated sheet, wherein the nanofiber layer or the ultra-thin sheet is attached to the surface of an object in a wet state.

[0318] <30> A method for producing a nanofiber sheet or a laminated sheet, wherein a raw material liquid is discharged from a nozzle with a high voltage applied between the nozzle and a counter electrode, and nanofibers generated from the raw material liquid are deposited on a collecting portion by an electrostatic spinning method;

[0319] The nanofibers are deposited on the collecting portion while moving at least one of the nozzle and the collecting portion, thereby manufacturing a prescribed nanofiber sheet or laminated sheet having a gradual region or a tapered peripheral region in which the thickness gradually increases from the peripheral end toward the inside.

[0320] <31> As mentioned above <30> A method for producing a nanofiber sheet or a laminated sheet, comprising:

[0321] A trajectory calculation step, which determines the moving trajectory of at least one of the nozzle and the collecting portion that can form the specified nanofiber sheet or layered sheet based on factors related to the stacking distribution of the nanofibers and the correlation between the thickness of the stacked nanofibers; and

[0322] The deposition step deposits the nanofibers while moving at least one of the nozzle and the collecting unit according to the moving trajectory determined in the trajectory calculation step.

[0323] <32> As mentioned above <31> A method for manufacturing a nanofiber sheet or a laminated sheet, wherein the factor related to the stacking distribution of the nanofibers is selected from one or a combination of two or more of the moving speed of the nozzle or the collecting section, the discharge speed of the raw material liquid, the potential difference between the nozzle and the counter electrode, the distance between the nozzle and the collecting section, the inner diameter of the nozzle and the material of the nozzle.

[0324] <33> As mentioned above <31> or <32> A method for manufacturing a nanofiber sheet or a laminated sheet, wherein the nanofiber sheet or laminated sheet has an inner square area surrounded by the gradient area when viewed from above;

[0325] In the trajectory calculation step, the movement trajectory is calculated so that the minimum thickness of the inner area becomes equal to or greater than a predetermined set value.

[0326] <34> As mentioned above <31> ~ <33> The method for producing a nanofiber sheet or a laminated sheet according to any one of the above, wherein the step of depositing the nanofibers on the collecting portion while moving at least one of the nozzle and the collecting portion comprises:

[0327] The first step is to move the nozzle and the collecting portion along the first moving track in such a manner that the deposited portion of the nanofibers forms a first strip-shaped deposited area; and the single or multiple second steps are to move the nozzle and the collecting portion along the second moving track in such a manner that the deposited portion of the nanofibers forms a second strip-shaped deposited area that continuously repeats the first or previously formed strip-shaped deposited area in a part of the width direction.

[0328] <35> As mentioned above <34> A method for producing a nanofiber sheet or a laminated sheet, wherein the position dividing the length of the strip-shaped stacking region in the width direction into two equal parts is set as the midpoint of the strip-shaped region, and the region where the strip-shaped stacking region overlaps with other strip-shaped stacking regions is set as the overlapping region,

[0329] The overlapping region is located between the midpoint of the band-shaped stacking region and the outer edge of the band-shaped stacking region on the side where the other band-shaped stacking regions are arranged in the width direction.

[0330] <36> As mentioned above <35> A method for manufacturing a nanofiber sheet or a laminated sheet, wherein in the width direction, within the range of the above-mentioned repeated area, there exists a midpoint of the above-mentioned band-shaped stacking area and a midpoint of the above-mentioned other band-shaped stacking areas.

[0331] <37> As mentioned above <34> ~ <36> The method for manufacturing a nanofiber sheet or a laminated sheet as described in any one of the preceding claims, wherein, when the previously determined moving track is used as the determined track, and the area surrounded by the first moving track or the area surrounded by the determined track is used as the determined track inner area,

[0332] In the trajectory calculation step, a similar trajectory that is circumferential and has a shape substantially similar to the planar shape of the nanofiber accumulation body, or a trajectory that is not circumferential, is calculated within the determined trajectory region.

[0333] <38> As mentioned above <37> A method for manufacturing a nanofiber sheet or a laminated sheet, wherein in the above-mentioned orbit calculation step, the above-mentioned similar orbit or the above-mentioned orbit that is not circumferential is calculated in conjunction with the area or shape of the range of the above-mentioned moving orbit.

[0334] <39> As mentioned above <37> or <38> A method for manufacturing a nanofiber sheet or a laminated sheet, wherein, in the above-mentioned track calculation step, it is determined whether the similar track is configured so that the above-mentioned determined track and the corresponding parts of the above-mentioned similar track are adjacent to each other.

[0335] <40> As mentioned above <30> ~ <39> The method for producing a nanofiber sheet or a laminated sheet according to any one of the above, wherein one or both of the nozzle and the collecting unit are moved at a predetermined speed.

[0336] <41> As mentioned above <30> ~ <40> A method for manufacturing a nanofiber sheet or a laminated sheet as described in any one of the above-mentioned descriptions, wherein the moving track on which the above-mentioned nozzle and any one of the above-mentioned collecting parts move is a track group that nests a plurality of tracks that are roughly similar in shape to each other, a combination of crossing lines that connect the above-mentioned plurality of tracks to each other, or a line that can be drawn in one stroke.

[0337] <42> As mentioned above <30> ~ <41> The method for manufacturing a nanofiber sheet or a laminated sheet as described in any one of the above, wherein the top view shape of the above-mentioned nanofiber sheet or the above-mentioned laminated sheet includes a shape of multiple curved portions with different curvatures in the outline, a shape of a shape including multiple straight portions in the outline, or a shape of a shape including the curved portion and the straight portion in the outline.

[0338] <43> As mentioned above <30> ~ <42> The method for producing a nanofiber sheet or a laminated sheet according to any one of the above, wherein a base layer is disposed on the collecting portion, and the nanofibers are deposited on the base layer.

[0339] <44> As mentioned above <43> A method for producing a nanofiber sheet or a laminated sheet, comprising a cutting step of cutting the nanofiber sheet, the substrate layer, or both of them, or the laminated sheet, the substrate layer, or both of them.

[0340] <45> As mentioned above <34> ~ <39> The method for producing a nanofiber sheet or a laminated sheet according to any one of the preceding claims, wherein:

[0341] The nanofiber sheet or laminated sheet specified above has an inner square area surrounded by the gradient area in a plan view;

[0342] When the area where the above-mentioned band-shaped stacking area overlaps with other band-shaped stacking areas is defined as an overlapping area,

[0343] The minimum thickness of the above-mentioned repeated area in the width direction is greater than 100%, preferably greater than 125% relative to the minimum thickness of the above-mentioned inner area; further, it is less than 250%, preferably less than 200%; further, it is greater than 100% and less than 250%, preferably greater than 125% and less than 200%.

[0344] <46> As mentioned above <45> A method for manufacturing a nanofiber sheet or a laminated sheet, wherein the minimum thickness of the above-mentioned repeated area is greater than 0.2 μm, preferably greater than 1 μm; further, it is less than 100 μm, preferably less than 10 μm; further, it is greater than 0.2 μm and less than 100 μm, preferably greater than 1 μm and less than 10 μm.

[0345] <47> As mentioned above <45> or <46> A method for manufacturing a nanofiber sheet or a laminated sheet, wherein the width of the above-mentioned repeated area is greater than 1%, preferably greater than 5% relative to the spacing distance between the midpoint of the stacking area and the midpoints of other stacking areas in the width direction; further, it is less than 90%, preferably less than 80%; further, it is greater than 1% and less than 90%, preferably greater than 5% and less than 80%.

[0346] <48> As mentioned above <45> ~ <47> The method for manufacturing a nanofiber sheet or a laminated sheet as described in any one of the preceding claims, wherein the width of the above-mentioned overlapping area in the width direction is greater than 1 mm, preferably greater than 4 mm; furthermore, is less than 80 mm, preferably less than 60 mm; furthermore, is greater than 1 mm and less than 80 mm, preferably greater than 4 mm and less than 60 mm.

[0347] <49> A manufacturing device for a nanofiber sheet or a laminated sheet, comprising a nozzle for discharging a raw material liquid, a counter electrode arranged to face the nozzle and generate an electric field between the nozzle, a collecting section for collecting nanofibers generated by electrically extending the raw material liquid, and a mechanism for moving at least one of the nozzle and the collecting section;

[0348] It can deposit the nanofibers on the collecting part while moving at least one of the nozzle and the collecting part according to the data of the moving track input into the control part;

[0349] The control unit may input or may input the <31> The data of the moving trajectory determined by the above-mentioned trajectory calculation step of the method for manufacturing a nanofiber sheet or a laminated sheet.

[0350] <50> A device for manufacturing a nanofiber sheet or a laminated sheet, comprising:

[0351] A nozzle for discharging the raw material liquid;

[0352] A power source for applying a voltage to the nozzle, or a counter electrode disposed opposite to the nozzle and generating an electric field between the nozzle and the counter electrode, and a power source for applying a voltage between the nozzle and the counter electrode;

[0353] A collecting portion for accumulating nanofibers generated from the raw material liquid;

[0354] a nozzle moving mechanism for moving the nozzle relative to the collecting portion; and

[0355] cutting the nanofiber sheet or the laminated sheet including the nanofiber layer deposited on the collection portion into a cut portion of a predetermined shape;

[0356] The nozzle moving mechanism and the cutting portion are supported by a common supporting portion.

[0357] <51> As mentioned above <50> A manufacturing device, wherein the cutting portion is mounted on the nozzle moving mechanism, whereby the nozzle moving mechanism and the cutting portion are supported by the common supporting portion.

[0358] <52> As mentioned above <50> A manufacturing device, further comprising a cutting portion moving mechanism for moving the cutting portion relative to the collecting portion, the cutting portion moving mechanism being supported by the supporting portion, whereby the cutting portion and the nozzle moving mechanism are supported by the common supporting portion.

[0359] <53> As mentioned above <50> ~ <52> The manufacturing apparatus described in any one of the above aspects may further include a collecting section moving mechanism for moving the collecting section along its collecting surface, wherein the collecting section moving mechanism is supported by the supporting section.

[0360] <54> A device for manufacturing a nanofiber sheet or a laminated sheet, comprising:

[0361] A nozzle for discharging the raw material liquid;

[0362] A power source for applying a voltage to the nozzle, or a counter electrode disposed opposite to the nozzle and generating an electric field between the nozzle and the counter electrode, and a power source for applying a voltage between the nozzle and the counter electrode;

[0363] A collecting portion for accumulating nanofibers generated from the raw material liquid;

[0364] a collecting portion moving mechanism for moving the collecting portion relative to the nozzle; and

[0365] cutting the nanofiber sheet or the laminated sheet including the nanofiber layer deposited on the collecting portion into a cut portion of a predetermined shape;

[0366] The collecting portion moving mechanism and the cutting portion are supported by a common supporting portion.

[0367] <55> As mentioned above <54> A manufacturing device, further comprising a cutting portion moving mechanism for moving the cutting portion relative to the collecting portion, the cutting portion moving mechanism being supported by the supporting portion, whereby the cutting portion and the collecting portion moving mechanism are supported by the common supporting portion.

[0368] <56> As mentioned above <50> ~ <55> The manufacturing device described in any one of the above aspects, wherein the cutting unit is a laser processing machine.

[0369] <57> As mentioned above <50> ~ <56> The manufacturing device described in any one of the above aspects, wherein the collecting section has air permeability.

[0370] <58> As mentioned above <50> ~ <57> The manufacturing device described in any one of the above, wherein the entire manufacturing device is covered by a protective member at least part of which has a transparent portion; the transparent portion is made of acrylic resin, polycarbonate resin or glass.

[0371] <59> As mentioned above <50> ~ <58> The manufacturing device described in any one of the above aspects further comprises a dust collecting and deodorizing mechanism.

[0372] <60> As mentioned above <50> ~ <59> The manufacturing device according to any one of the preceding claims, wherein the nanofiber sheet or laminated sheet comprises a layer of the nanofibers and a substrate layer supporting the layer,

[0373] The cutting unit is configured to cut only the nanofiber layer, only the base layer, or the entire nanofiber sheet or laminated sheet.

[0374] <61> A device for manufacturing a nanofiber sheet or a laminated sheet, comprising:

[0375] A chuck portion including a receiving portion for receiving a raw material liquid, a nozzle for discharging the raw material liquid, and a supply portion for supplying the raw material liquid from the receiving portion to the nozzle;

[0376] A power source for applying a voltage to the nozzle, or a counter electrode disposed opposite to the nozzle and generating an electric field between the nozzle and the counter electrode, and a power source for applying a voltage between the nozzle and the counter electrode;

[0377] The mounting portion of the above-mentioned brake portion; and

[0378] A collecting portion for collecting nanofibers generated by electrically stretching the raw material solution;

[0379] The above-mentioned clamping part is detachably mounted on the above-mentioned mounting part;

[0380] The mounting portion is provided with a driving source for driving the supply portion in the clamp portion in a state where the clamp portion is mounted on the mounting portion.

[0381] <62> A device for manufacturing a nanofiber sheet or a laminated sheet, comprising:

[0382] A chuck portion including a receiving portion for receiving a raw material liquid, a nozzle for discharging the raw material liquid, and a supply portion for supplying the raw material liquid from the receiving portion to the nozzle;

[0383] A power source for applying a voltage to the nozzle, or a counter electrode disposed opposite to the nozzle and generating an electric field between the nozzle and the counter electrode, and a power source for applying a voltage between the nozzle and the counter electrode;

[0384] The mounting portion of the above-mentioned brake portion; and

[0385] A collecting portion for collecting nanofibers generated by electrically stretching the raw material solution;

[0386] The mounting portion is provided with a driving source for driving the supply portion in the clamp portion when the clamp portion is mounted on the mounting portion;

[0387] In the above-mentioned clamping portion, the above-mentioned storage portion can be detachably mounted on the above-mentioned supply portion.

[0388] <63> As mentioned above <61> or <62> A manufacturing device, wherein, in the above-mentioned gate portion, the above-mentioned receiving portion is detachably mounted on the above-mentioned supply portion.

[0389] <64> As mentioned above <61> ~ <63> In any one of the manufacturing devices described above, the mounting portion is composed of a moving mechanism of at least one axis.

[0390] <65> As mentioned above <61> ~ <64> The manufacturing device described in any one of the above aspects, wherein the collecting section includes a moving mechanism of at least one axis.

[0391] <66> As mentioned above <61> ~ <65> The manufacturing device described in any one of the above aspects, wherein the shutter portion is mounted on the mounting portion in an electrically insulated state.

[0392] <67> As mentioned above <61> ~ <66> In any one of the above manufacturing devices, the mounting portion, the collecting portion, and the power source are supported by a common supporting portion.

[0393] <68> As mentioned above <61> ~ <67> The manufacturing device described in any one of the above, wherein in the gate portion, the storage portion, the supply portion, and the nozzle are directly connected.

[0394] <69> A method for manufacturing an ultra-thin sheet material, wherein a raw material liquid is discharged from a nozzle, and fibers or particles generated from the raw material liquid are deposited on a collecting portion, thereby manufacturing an ultra-thin sheet material having a thickness of 5.1 μm or more and 500 μm or less;

[0395] The method for manufacturing an ultra-thin sheet comprises: a target shape forming step of discharging the raw material liquid within the range of the contour shape of the ultra-thin sheet while moving at least one of the nozzle and the collecting portion based on information related to the target contour shape of the ultra-thin sheet;

[0396] In the target shape forming step, the raw material liquid is discharged so as to form a tapered peripheral region within 5 mm in width, the thickness of which gradually increases inward from the peripheral end of the outline shape.

[0397] [Example]

[0398] The present invention is described in more detail below by way of examples. However, the scope of the present invention is not limited to the examples. Unless otherwise specified, "%" means "mass %".

[0399] [Examples 1 to 9]

[0400] like Figure 1 As shown, a nanofiber layer having a concave-convex top view formed by multiple curved portions with different curvatures is manufactured in such a way that the width of the gradient region is 3 mm or more, or 4 mm or more. The maximum length of this nanofiber layer in its top view is 30 mm. Specifically, a nanofiber layer composed of nanofibers of polyvinyl butyral (PVB, manufactured by Sekisui Chemical Co., Ltd., S-LEC BBM-1) is formed by the above-mentioned manufacturing method. The thickness of the nanofiber is 100 nm. The nanofiber layer is formed by electrospinning using a raw material liquid containing 12% PVB, 61.25% ethanol, 26.25% 1-butanol, and 0.5% quaternary salt-type surfactant (manufactured by Kao Corporation, trade name "SANISOL C"). The implementation conditions of the electrospinning method are set to a voltage of 30 kV, a spacing of 200 mm between the nozzle tip and the counter electrode, and a discharge volume of 1 ml / h. The accumulation of fibers by electrospinning is performed while moving the nozzle in the planar direction. For the obtained nanofiber layer, the thickness D1 of the peripheral end of the nanofiber layer, the width W1 of the gradient region, and the thickness D3 of the maximum thickness portion 15 are measured by the above-mentioned measurement method. In addition, the inclination angle θ is calculated by the thickness difference D2 between the peripheral end 17 and the maximum thickness portion 15 in the gradient region G, and the width W1 of the gradient region G. The measurement results and calculation results are shown in Table 1 below. In each of the nanofiber layers of Examples 1 to 5, the width W1 of the gradient region in the entire region of the nanofiber layer is visually equal. In addition, in each of the nanofiber layers of Examples 6 to 9, the width W1 of the gradient region in the entire region of the nanofiber layer is visually equal. In addition, in any embodiment, the proportion (%) of the portion composed of the curve in the total length of the contour line of the nanofiber layer when viewed from above is 100%. That is, the total length of the contour line of the nanofiber layer when viewed from above is composed of the curve.

[0401] [Comparative Examples 1 and 2]

[0402] The nanofiber layer was formed by electrospinning under the same conditions as in Example 1, except that a raw material solution containing 12% PVB and 88.0% ethanol was used, the thickness of the peripheral edge of the nanofiber layer was set to 12 μm or 15 μm, and the thickness D3 of the maximum thickness portion of the gradient region G was set to 15 μm or 20 μm. The nanofiber layer had a thickness of 500 nm. The measurement results are shown in Table 1 below.

[0403] [evaluate]

[0404] The visibility of the nanofiber layers obtained in Examples and Comparative Examples and the appearance of the nanofiber layers after foundation application were evaluated by the following methods when the nanofiber layers were attached to the skin. The evaluation results are shown in Table 1 below.

[0405] [Visibility of the nanofiber layer]

[0406] 5 mL / cm2 of essence (trade name: RISE LOTION II (refreshing type), manufactured by Kao Corporation) was applied to the inner part of the upper arm of the test subject to make it wet, and the first surface, i.e., the raised surface, of the nanofiber layer was attached to this part. Then, the attached nanofiber layer was visually inspected and its visibility was evaluated according to the following criteria. The evaluation results are shown in Table 1.

[0407] A: The nanofiber layer has high transparency as a whole and is very superior in that it is difficult to visually identify the nanofiber layer.

[0408] B: The peripheral edge of the entire nanofiber layer is transparent, and the nanofiber layer is difficult to visually recognize, which is excellent.

[0409] C: The nanofiber layer has low transparency as a whole and is easily visually recognizable, but is not excellent in that the nanofiber layer is difficult to visually recognize.

[0410] [Appearance of the nanofiber layer with foundation applied]

[0411] In the above-mentioned [Visibility of Nanofiber Layer], 0.71 mg / cm 2 The nanofiber layer was then visually inspected and its appearance was evaluated according to the following criteria. The evaluation results are shown in Table 1.

[0412] A: The nanofiber layer blends into the surrounding skin, giving a natural finish.

[0413] B: The edge of the nanofiber layer is obvious and does not blend into the surrounding skin, giving an unnatural finish.

[0414] [Table 1]

[0415]

[0416] As shown in Table 1, the nanofiber layers of each example are not easily visually recognizable when attached to the skin, and even if foundation is applied thereon, they still blend into the skin and present a natural makeup look. In contrast, the nanofiber layers of each comparative example are clearly visible when attached to the skin and can be visually recognizable. Furthermore, when foundation is applied thereon, the nanofiber layers of each comparative example present a different color tone from the surrounding skin, do not blend into the skin, and present an unnatural makeup look.

[0417] The hiding ability of the nanofiber layer on the skin with the nanofiber layer attached to the skin and the hiding ability of the nanofiber layer on the skin with foundation applied on the nanofiber layer were evaluated using the following method.

[0418] [Concealment of spots and wrinkles]

[0419] The nanofiber layer was attached to the skin with spots or wrinkles in the same manner as in [Appearance of the nanofiber layer with foundation applied], and foundation was applied thereon. The spots or wrinkles in the area were then visually observed, and the concealing properties were evaluated according to the following criteria.

[0420] 3: Skin spots and wrinkles are concealed to the point where they are no longer visible.

[0421] 2: Spots or wrinkles on the skin are slightly visible, but difficult to identify visually.

[0422] 1: Spots and wrinkles can be easily identified visually.

[0423] The evaluation of the above-mentioned [hiding property of spots or wrinkles] was performed using the nanofiber layer of Example 4 and the nanofiber layer of Example 10. The nanofiber layer of Example 10 was produced in the same manner as in Example 4, except that the thickness D3 of the maximum thickness portion of the gradient region was set to 50 μm. The evaluation results are shown in Table 2 below.

[0424] [Table 2]

[0425]

[0426] The nanofiber layer of the present invention can improve its concealing property by applying foundation on the nanofiber layer. For example, in Examples 4 and 10, spots or wrinkles can be effectively concealed. In addition, by increasing the thickness of the maximum thickness portion of the gradient region, spots or wrinkles can be concealed to the extent that they are not visible.

[0427] [Reference example]

[0428] According to the same procedure as in Example 1, a nanofiber layer with a thickness of 41 μm at the apex position was manufactured. The profile of this nanofiber layer when viewed from above is similar to Figure 1For the manufactured nanofiber layer, the three-dimensional shape data is obtained according to the above method, and a graph representing the cross-sectional profile curve is obtained based on the data. In the obtained graph, the corresponding Figure 1 The profile curve of the cross section at the II-II line position is shown in Fig. 22 . Fig. 22 The cross-sectional profile curve, the peripheral edge CP, the gradual change region G, and the vertex position CT of the nanofiber layer are shown. Fig. 22 In the cross-sectional profile curve shown, the thickness D1 at the peripheral end is 4.5 μm, and the thickness of the gradual change region increases in an S-curve shape from the peripheral end to the vertex position.

[0429] (Industrial Applicability)

[0430] According to the present invention, a nanofiber sheet having a nanofiber layer that is difficult to visually recognize when attached to the skin and a method of using the same can be provided. In addition, according to the present invention, a nanofiber sheet having a nanofiber layer that is difficult to visually recognize when attached to the skin can be manufactured.

Claims

1. A nanofiber sheet, wherein: The invention comprises a substrate layer and a nanofiber layer, wherein the nanofiber layer is disposed on one side of the substrate layer and contains a polymer compound. The surface of the nanofiber layer opposite to the substrate layer is attached to the surface of an object for use. The thickness of the peripheral edge of the nanofiber layer is not less than 0.1 μm and not more than 10 μm, and has a gradual change region in which the thickness gradually increases from the peripheral edge toward the inner side. The distance between the maximum thickness portion of the gradual change area and the peripheral edge is greater than 3 mm. The surface of the substrate layer opposite to the nanofiber layer is flat.

2. The nanofiber sheet according to claim 1, wherein The base layer has a region extending outward from a peripheral edge of the nanofiber layer.

3. The nanofiber sheet according to claim 1, wherein: The nanofiber layer is releasably laminated on the substrate layer.

4. The nanofiber sheet according to claim 2, wherein: The nanofiber layer is releasably laminated on the substrate layer.

5. The nanofiber sheet according to any one of claims 1 to 4, wherein The difference in thickness between the inner end and the peripheral end of the gradual change region is 5 μm or more.

6. The nanofiber sheet according to any one of claims 1 to 4, wherein The top view shape of the nanofiber layer is: a shape including a plurality of curved portions with different curvatures in its outline, a shape including a plurality of straight portions in its outline, or a shape including the curved portion and the straight portion in its outline.

7. The nanofiber sheet according to any one of claims 1 to 4, wherein The nanofiber layer is disposed adjacent to the base layer, and the base layer has air permeability.

8. The nanofiber sheet according to any one of claims 1 to 4, wherein The nanofiber layer is disposed adjacent to the base layer, and the base layer has a plurality of concave or convex portions having a width greater than a fiber diameter of the nanofibers on a surface facing the nanofiber layer.

9. The nanofiber sheet according to any one of claims 1 to 4, wherein The nanofiber layer is water-insoluble.

10. The nanofiber sheet according to any one of claims 1 to 4, wherein including an adhesive layer that can be attached to the surface of an object; The adhesive layer is disposed on the surface of the nanofiber layer opposite to the base layer.

11. A method for using a nanofiber sheet, wherein: The method of use is a method of using a nanofiber sheet comprising a substrate layer and a nanofiber layer disposed on one side of the substrate layer and containing nanofibers of a polymer compound, wherein the thickness of the peripheral end of the nanofiber layer is 0.1 μm or more and 10 μm or less, and the nanofiber sheet has a gradual change region in which the thickness gradually increases from the peripheral end toward the inner side. The distance between the maximum thickness portion of the gradual change area and the peripheral edge is greater than 3 mm. The nanofiber layer is used by making the surface opposite to the substrate layer contact with the surface of the object. The surface of the substrate layer opposite to the nanofiber layer is flat.

12. The method for using the nanofiber sheet according to claim 11, wherein: The nanofiber layer is used in a wet state.

13. The method for using the nanofiber sheet according to claim 11, wherein: The substrate layer is peeled off and used.

14. The method for using the nanofiber sheet according to any one of claims 11 to 13, wherein: When used, the base layer is peeled off and the nanofiber layer is attached to the surface of the skin for use.

15. The method for using the nanofiber sheet according to claim 9, wherein: Used as a cosmetic sheet.

16. A method for producing a nanofiber sheet according to any one of claims 1 to 10, wherein: The manufacturing method is a method for manufacturing a nanofiber sheet by discharging a raw material liquid from a nozzle with a high voltage applied between the nozzle and a counter electrode, and depositing nanofibers generated from the raw material liquid on a collecting part by an electrospinning method. The nanofibers are deposited on the collecting part while at least one of the nozzle and the collecting part is moved, thereby manufacturing a predetermined nanofiber sheet having a gradual change region in which the thickness gradually increases from the peripheral end toward the inner side.

17. The method for producing a nanofiber sheet according to claim 16, wherein: include: A trajectory calculation step of determining a moving trajectory of at least one of the nozzle and the collecting portion capable of forming the specified nanofiber sheet based on a correlation between factors related to the accumulation distribution of the nanofibers and the thickness of the accumulated nanofibers; and The deposition step deposits the nanofibers while moving at least one of the nozzle and the collecting unit according to the movement trajectory determined in the trajectory calculation step.

18. The method for producing a nanofiber sheet according to claim 17, wherein: The factors related to the stacking distribution of nanofibers are selected from one or a combination of two or more of the moving speed of the nozzle or the collecting section, the discharge speed of the raw material liquid, the potential difference between the nozzle and the counter electrode, the distance between the nozzle and the collecting section, the inner diameter of the nozzle and the material of the nozzle.

19. The method for producing a nanofiber sheet according to claim 17, wherein: The predetermined nanofiber sheet has an inner region surrounded by the gradient region when viewed from above, In the trajectory calculation step, the movement trajectory is calculated so that the minimum thickness of the inner region becomes equal to or greater than a predetermined set value.

20. The method for producing a nanofiber sheet according to any one of claims 17 to 19, wherein: The step of depositing the nanofibers on the collecting part while moving at least one of the nozzle and the collecting part comprises: The first step is to move one of the nozzle and the collecting part along a first moving track so that the deposited part of the nanofiber forms a first belt-shaped deposited area; and In a single or multiple second steps, any one of the nozzle and the collecting portion is moved along the second moving track in such a manner that the nanofiber deposition portion forms a second band-shaped deposition area that continuously repeats the first or previously formed band-shaped deposition area in a portion of the width direction.

21. The method for producing a nanofiber sheet according to any one of claims 17 to 19, wherein: Either or both of the nozzle and the collecting portion are moved at a constant speed.

22. The method for producing a nanofiber sheet according to any one of claims 17 to 19, wherein: The movement track of any one of the nozzle and the collecting part is a combination of a track group including a plurality of tracks having the same shape in a nested manner and a crossing line connecting the plurality of tracks, or a line shape that can be drawn with one stroke.

23. A device for manufacturing a nanofiber sheet, wherein: The nanofiber sheet manufacturing device comprises: a nozzle for discharging a raw material liquid; a counter electrode arranged opposite to the nozzle and generating an electric field between the nozzle and the counter electrode; a collecting part for collecting nanofibers generated by electrically extending the raw material liquid; and a mechanism for moving at least one of the nozzle and the collecting part; Based on the data of the moving trajectory input into the control unit, at least one of the nozzle and the collecting unit can be moved while the nanofibers are deposited on the collecting unit; The control unit receives or can receive data on the movement trajectory determined in the trajectory calculation step of the method for producing a nanofiber sheet according to claim 17 .

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