Manufacturing method of hollow protruding tool and hollow protruding tool

Abstract

To provide a hollow projection tool which maintains strength by suppressing the embrittlement of the peripheral part of a through hole formed in a fine hollow projection.SOLUTION: Provided is a manufacturing method for a hollow projection tool 1 including a hole formation step of forming a through hole 3h in a fine hollow projection 3. The through hole 3h is formed by irradiating proximate portions of the same surface of the hollow projection 3 multiple times with a laser beam having output of penetrating the hollow projection 3 in one-time irradiation with an aperture diameter smaller than an aperture diameter of the through hole 3h.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a method for manufacturing a hollow protruding tool and a hollow protruding tool. [Background technology]

[0002] A hollow protrusion device called a microneedle array is known as a device that supplies a drug to the skin by puncturing the skin with hollow protrusions equivalent to microscopic needles. For example, Patent Documents 1 to 3 disclose a method for manufacturing a hollow protrusion device that forms a through hole by irradiating a laser beam from a laser irradiation device, which is a non-contact hole opening means, to the hollow protrusions. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-50927 A [Patent Document 2] International Publication No. 2015 / 125475 [Patent Document 3] JP 2011-72695 A Summary of the Invention [Problem to be solved by the invention]

[0004] The techniques described in Patent Documents 1 to 3 do not take into consideration that when a through hole is formed in a hollow protrusion with a laser beam, the heat of the laser beam can weaken the area surrounding the through hole, posing issues with the strength of the hollow protrusion.

[0005] SUMMARY OF THE PRESENT EMBODIMENTS Accordingly, an object of the present invention is to provide a method for manufacturing a hollow protrusion device and a hollow protrusion device that can solve the problems associated with the prior art described above. [Means for solving the problem]

[0006] The present invention provides a method for manufacturing a hollow protrusion tool, which includes an aperture formation step for forming a through hole in a fine hollow protrusion, in which the through hole is formed by irradiating the hollow protrusion with a laser beam multiple times from a laser irradiation device, which is a non-contact aperture means, with a laser beam of an output that does not penetrate the intended aperture position of the hollow protrusion in each irradiation, thereby forming the through hole. The present invention provides a method for manufacturing a hollow protrusion tool, which includes an aperture forming step for forming a through hole in a fine hollow protrusion, in which the through hole is formed by irradiating adjacent portions of the same surface of the hollow protrusion with a laser beam having an output such that in a single irradiation, the hollow protrusion has an aperture diameter smaller than the aperture diameter of the through hole, thereby forming the through hole. The present invention provides a hollow protrusion tool having a fine hollow protrusion portion having a through hole, the hollow protrusion tool being manufactured by any one of the above-mentioned manufacturing methods. Effect of the Invention

[0007] According to the present invention, the thermal effect of irradiation with a laser beam when forming a through hole in the hollow protrusion is reduced, thereby preventing the surrounding area of ​​the through hole from becoming weakened and maintaining the strength of the hollow protrusion, thereby suppressing deformation of the hollow protrusion when puncturing the skin, making it possible to provide a hollow protrusion device that is easy to puncture the skin. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view that shows a schematic example of a hollow protrusion tool in which minute hollow protrusions having through holes are arranged, the hollow protrusion tool being manufactured by the method for manufacturing a hollow protrusion tool of the present invention. [Diagram 2] FIG. 2 is an enlarged perspective view of the hollow protrusion tool, focusing on one of the hollow protrusions shown in FIG. [Diagram 3] FIG. 3 is a cross-sectional view taken along line III-III shown in FIG. [Figure 4] FIG. 4 is a diagram showing the overall configuration of a manufacturing apparatus used in a preferred embodiment for manufacturing the hollow protrusion tool shown in FIG. [Diagram 5] 5(a) to (e) are diagrams illustrating a method for producing a hollow protrusion tool having a fine hollow protrusion portion with a through hole, using the production apparatus shown in FIG. [Figure 6] 6(a) to (d) are diagrams showing the process of forming a through hole according to the first embodiment of the present invention. [Figure 7] FIG. 7(a) is an enlarged view of a hollow protrusion in which a through hole is formed by the manufacturing method of the first embodiment, viewed from the irradiation side, and FIG. 7(b) is an enlarged view showing the through hole and the surrounding area affected by heat when the through hole is formed. [Figure 8] 8(a) to (d) are diagrams showing the process of forming a through hole according to the second embodiment of the present invention. [Figure 9] FIG. 9(a) is an enlarged view from the irradiation side showing a state in which multiple apertures smaller than the aperture diameter of the through hole are formed by the manufacturing method of the second embodiment, FIG. 9(b) is a partially enlarged view showing the process of forming a through hole by moving the irradiation position of the laser beam to the apex position of a triangle, and FIG. 9(c) is a partially enlarged view showing the process of forming a through hole by overlapping multiple through apertures. [Figure 10] Figure 10(a) is an enlarged view explaining a configuration in which multiple through holes are arranged adjacent to each other in the protruding direction of a hollow protrusion portion, and Figure 10(b) is an enlarged view showing a configuration in which multiple through holes are formed in line symmetry. [Figure 11] FIG. 11 is a diagram for explaining a manufacturing method of another embodiment for manufacturing the hollow protrusion tool shown in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, the present invention will be described based on preferred embodiments thereof with reference to the drawings. The manufacturing method of the present invention is a method for manufacturing a hollow protrusion tool having a hollow interior. FIG. 1 shows a perspective view of a fine hollow protrusion tool 1 of one embodiment manufactured by the manufacturing method of a fine hollow protrusion tool of the embodiment. The hollow protrusion tool 1 has a base 2 which is a flat sheet-like substrate, and a plurality of fine hollow protrusions 3. There is no particular limitation on the number of hollow protrusions 3, the arrangement of the hollow protrusions 3, and the shape of the hollow protrusions 3, but the hollow protrusion tool 1 of this embodiment preferably has nine truncated cone-shaped hollow protrusions 3 in an array (matrix) on the upper surface of the sheet-like base 2. The nine hollow protrusions 3 arranged in an array (matrix) are arranged in three rows in the Y direction, which is the direction in which the substrate sheet 2A described below is transported (the vertical direction of the substrate sheet 2A), and in three columns in the X direction, which is the direction perpendicular to the transport direction and the horizontal direction of the substrate sheet 2A being transported.

[0010] Fig. 2 is a perspective view of the hollow protrusion device 1 focusing on one of the hollow protrusions 3 arranged in the hollow protrusion device 1, and Fig. 3 is a cross-sectional view taken along line III-III in Fig. 2. The hollow protrusion device 1 is a so-called microneedle array, and by pressing the hollow protrusion 3 against the skin, for example, to puncture the skin, an agent enclosed inside the hollow protrusion 3 is supplied to the inside of the skin through the through-holes 3h. The microneedle array is an example of the hollow protrusion device 1, and the hollow protrusion device 1 is not limited to a microneedle array.

[0011] As shown in FIG. 2, the hollow protrusion tool 1 has a through hole 3h in the hollow protrusion 3. As shown in FIG. 3, the hollow protrusion tool 1 has a base side opening 2h at a position corresponding to each hollow protrusion 3 in the base part 2. In the hollow protrusion tool 1, a space 3k is formed that extends from the base side opening 2h of the base part 2 through the inside of each hollow protrusion 3 to the through hole 3h on the tip side. Therefore, the through hole 3h is formed penetrating from the outside of the hollow protrusion 3 to the internal space 3k. The internal space 3k of each hollow protrusion 3 is formed in a shape corresponding to the external shape of the hollow protrusion 3, and in the hollow protrusion tool 1 shown in FIG. 1, it is formed in a cone shape corresponding to the external shape of the cone-shaped hollow protrusion 3. The external shape of the hollow protrusion 3 is cone-shaped, but it may be a truncated cone shape, a cylindrical shape, a prism shape, a pyramid shape, a truncated pyramid shape, or the like, in addition to the cone shape.

[0012] 2, the through hole 3h is an opening formed at a planned opening position offset from the center of the tip of the hollow protrusion 3. When the through hole 3h is formed at a position offset from the center of the tip of the hollow protrusion 3 in this way, the through hole 3h is less likely to be crushed when the hollow protrusion 3 is punctured into the skin, and the agent can be stably supplied from the hollow protrusion tool 1 to the inside of the skin through the through hole 3h.

[0013] When used as a microneedle, the tip of each hollow protrusion 3 penetrates into the stratum corneum of the skin at the shallowest point and into the dermis at the deepest point, so that the protrusion height H1 (see FIG. 3) is defined in this embodiment as follows: The protrusion height H1 is preferably 0.01 mm or more, more preferably 0.02 mm or more, and preferably 10 mm or less, and more preferably 5 mm or less, specifically, preferably 0.01 mm or more and 10 mm or less, and more preferably 0.02 mm or more and 5 mm or less.

[0014] 7(b), the through hole 3h is formed such that the opening area S1 of the opening diameter r1 formed on the outer surface 32 side of the hollow protrusion 3 is larger than the opening area S2 of the opening diameter r3 formed inside the inner surface 31 of the hollow protrusion 3. That is, the through hole 3h is formed such that the inner diameter (opening diameter) on the outer surface 32 side of the hollow protrusion 3 is larger than the inner diameter (opening diameter) on the inner surface 31 side of the hollow protrusion 3. The inner diameter (opening diameter) on the inner surface 31 side is the diameter at the widest position of the through hole 3h formed on the inner surface 31, and the inner diameter on the outer surface 32 side is the diameter at the widest position of the through hole 3h formed on the outer surface 32. From the viewpoint of stably supplying the agent to the inside of the skin through the through hole 3h of the hollow protrusion portion 3, the inner diameter of the inner surface 31 of the through hole 3h is preferably 1 μm or more, more preferably 5 μm or more, and preferably 500 μm or less, more preferably 300 μm or less, specifically, preferably 1 μm or more and 500 μm or less, more preferably 5 μm or more and 300 μm or less.

[0015] From the viewpoint of stably supplying the agent to the inside of the skin through the through-hole 3h of the hollow protrusion 3, the inner diameter of the outer surface 32 side of the through-hole 3h is preferably 1.1 times or more, more preferably 1.2 times or more, and more preferably 15 times or less, and more preferably 10 times or less, compared to the inner diameter of the inner surface 31 side, specifically, preferably 1.1 times or more and 15 times or less, and more preferably 1.2 times or more and 10 times or less. From the viewpoint of more stably supplying the agent to the inside of the skin through the through-hole 3h of the hollow protrusion 3, it is preferable that the inner diameter of the through-hole 3h gradually increases from the inner surface 31 side to the outer surface 32 side of the hollow protrusion 3. That is, by irradiating the laser beam 4L from the outside of the hollow protrusion 3, the hollow protrusion 3 is formed with a through-hole 3h in which the opening diameter formed on the outside of the hollow protrusion is larger than the opening diameter formed on the inside of the hollow protrusion. The shape of the through-hole 3h is formed in a truncated cone shape.

[0016] Next, a method for manufacturing the hollow protrusion tool of the present invention will be described with reference to Figures 4 and 5, taking the method for manufacturing the hollow protrusion tool 1 described above as an example. Figure 4 shows the overall configuration of a manufacturing apparatus 100 of one embodiment used to implement the method for manufacturing the hollow protrusion tool 1. As described above, each hollow protrusion portion 3 of the hollow protrusion tool 1 is very small, but for convenience of explanation, each hollow protrusion portion 3 of the hollow protrusion tool 1 is exaggerated in Figure 4.

[0017] As shown in FIG. 4, the manufacturing apparatus 100 includes a protrusion forming section 10 having a convex mold section 11 for forming a hollow protrusion 3 in the base sheet 2A, and an opening forming section 40 having a non-contact type opening means for forming a through hole 3h in the hollow protrusion 3. In this embodiment, the manufacturing apparatus 100 includes a cooling section 20. The manufacturing apparatus 100 inserts the convex mold section 11 from one surface 2D side of the base sheet 2A to form a non-through hollow protrusion 3 protruding from the other surface 2U side of the base sheet 2A, and then forms a through hole 3h in the non-through hollow protrusion 3 from the other surface 2U side of the base sheet 2A by the opening means. The base section 2 indicates a portion of the hollow protrusion tool 1 formed from the base sheet 2A where the hollow protrusion 3 is not formed.

[0018] A detailed description will be given of a manufacturing method for the hollow protrusion tool 1 using the manufacturing apparatus 100. In the following description, the direction in which the base sheet 2A is transported is defined as the Y direction, the direction perpendicular to the transport direction and the second direction of the transported base sheet 2A is defined as the X direction, and the thickness direction of the transported base sheet 2A is defined as the Z direction. In the manufacturing method of the hollow protrusion tool 1 using the manufacturing apparatus 100, first, as shown in Fig. 4, a strip-shaped base sheet 2A is unwound from a raw material roll of the base sheet 2A and conveyed in the conveying direction Y. Then, when the base sheet 2A has been conveyed to a predetermined position, the conveying of the base sheet 2A is stopped. In this manner, in the manufacturing method of the hollow protrusion tool 1, the conveying of the strip-shaped base sheet 2A is performed intermittently.

[0019] The base sheet 2A is a sheet that will be the base material of the hollow protrusion tool 1 to be manufactured, and contains a thermoplastic resin. The base sheet 2A is preferably made mainly of a thermoplastic resin, i.e., contains 50% by mass or more of a thermoplastic resin, and more preferably contains 90% by mass or more of a thermoplastic resin. Examples of thermoplastic resins include polyolefin resins such as polyethylene, polypropylene, ethylene-α-olefin copolymer, and ethylene-propylene copolymer; polyester resins such as polyethylene terephthalate, polybutylene terephthalate, liquid crystal polymer, polyhydroxyalkanoate, polycaprolactone, polybutylene succinate, polyglycolic acid, polylactic acid, and polylactic acid-hydroxycarboxylic acid copolymer polylactic acid-based resins; polyamide resins such as nylon 6 and nylon 66; vinyl polymers such as polyvinyl chloride, polyvinylidene chloride, polyvinyl acetate, polyvinyl acetate-ethylene copolymer, and polystyrene; acrylic polymers such as polyacrylic acid, polyacrylic acid ester, polymethacrylic acid, and polymethacrylic acid ester; polycarbonate; polyamide imide; aromatic polyether ketone resins such as polyether ketone, polyether ether ketone, and polyether ether ketone ketone; polyether imide; and modified cellulose obtained by chemically modifying cellulose molecules. The base sheet 2A may be formed of a mixture containing hyaluronic acid, collagen, starch, cellulose, etc. in addition to the thermoplastic resin. The thickness of the base sheet 2A is equal to the thickness T2 (see FIG. 3) of the base portion 2 of the hollow protrusion device 1. In other words, the hollow protrusion portion 3 is preferably formed of a material containing a thermoplastic resin.

[0020] Next, in the manufacturing method of the hollow protrusion device 1, a protrusion forming process is performed in which, as shown in Figure 4, a convex portion 11 provided on the protrusion forming portion 10 is inserted from one surface 2D side of the strip-shaped base sheet 2A to form fine hollow protrusions 3 protruding from the other surface 2U side of the base sheet 2A.

[0021] As shown in FIG. 4, the protrusion forming section 10 is provided with a convex portion 11 for forming protrusions. The convex portion 11 may or may not be provided with a heating means (not shown), but the manufacturing apparatus 100 is provided with a heating means (not shown). The manufacturing apparatus 100 may not be provided with any other heating means other than the heating means for the convex portion 11. In this specification, "no other heating means other than the heating means for the convex portion 11" does not only refer to the case where no other heating means are provided, but also includes the case where a means for heating to a temperature below the softening temperature or below the glass transition temperature of the base sheet 2A is provided. However, it is preferable that no other heating means are provided.

[0022] The convex part 11 is a member having a convex mold 110 which is a part that is inserted into the base sheet 2A, and in the manufacturing apparatus 100, the convex part 11 is structured to be arranged on a disk-shaped base part. However, without being limited thereto, the convex part may be composed of only the convex mold 110, or the convex part 11 may have a plurality of convex molds 110 arranged on a platform support. The convex part 11 has convex molds 110 corresponding to the number, arrangement, and approximate outer shape of each hollow protrusion 3 of the hollow protrusion tool 1 to be manufactured, and in the manufacturing apparatus 100, nine cone-shaped convex molds 110 are provided corresponding to the nine cone-shaped hollow protrusions 3.

[0023] As shown by the dashed lines in Fig. 4, the convex mold 110 is formed in the shape of a cone with nine sharp tips, and the tips are arranged facing upward in the thickness direction Z. The convex mold portion 11 is arranged on one surface 2D (lower surface side) of the base sheet 2A at a certain distance downward in the thickness direction Z from the one surface 2D. The convex mold portion 11 is movable up and down in the thickness direction Z by an electric actuator (not shown). The convex mold 110 is configured so that the tips of the convex mold 110 of the convex mold portion 11 can abut from the one surface 2D side of the base sheet 2A.

[0024] In this embodiment, the heating means for the convex portion 11 is an ultrasonic vibration device. The ultrasonic vibration of the convex portion 11 is preferably performed from just before the convex portion 11 contacts the base sheet 2A until just before the next step, a cooling step described below. The operation of the convex portion 11 and the heating conditions of the heating means provided in the convex portion 11, such as the operation of the heating means for the convex portion 11, are controlled by a control means (not shown) provided in the manufacturing apparatus 100.

[0025] The shape of the tip side of the convex mold portion 11 may be a shape corresponding to the outer shape of the hollow protrusion portion 3 of the hollow protrusion tool 1 to be manufactured. The height of the convex mold 110 of the convex mold portion 11 is formed to be the same as or slightly higher than the protruding height H1 (see FIG. 3) of the hollow protrusion portion 3 of the hollow protrusion tool 1 to be manufactured.

[0026] 4, the protrusion forming section 10 has a first opening plate 12U as a deflection suppressing means on the other side 2U side (upper side) of the base sheet 2A, and a second opening plate 12D as a deflection suppressing means on one side 2D side (lower side) of the base sheet 2A. The first and second opening plates 12U, 12D are formed of plate-like members extending parallel to the conveying direction Y. The first and second opening plates 12U, 12D sandwich the base sheet 2A in an area other than the opening 12a.

[0027] The first and second opening plates 12U and 12D may be formed with an opening area larger than the cross-sectional area of ​​each convex mold 110 so that a plurality of convex molds 110 in the convex mold portion 11 can be inserted into one opening 12a, but in this embodiment, as shown in Figures 4 and 5, they are formed so that one convex mold 110 is inserted into one opening 12a. The opening 12a of the first opening plate 12U is arranged concentrically with the opening 12a of the second opening plate 12D in the manufacturing apparatus 100. Therefore, the opening 12a of the pair of the first opening plate 12U and the opening 12a of the second opening plate 12D that sandwich the base sheet 2A overlap in the thickness direction.

[0028] The first and second opening plates 12U, 12D are movable in a direction in which they abut against the base sheet 2A and in a direction in which they move away from the base sheet 2A. In the manufacturing apparatus 100, the first and second opening plates 12U, 12D are movable up and down in the thickness direction Z by an electric actuator (not shown). The operations of the first and second opening plates 12U, 12D are controlled by a control means (not shown) provided in the manufacturing apparatus 100. In this embodiment, the first opening plate 12U and the second opening plate 12D are movable in a direction to abut against and away from the base sheet 2A. Of these, the second opening plate 12D does not have to be movable in a direction to abut against and away from the base sheet 2A.

[0029] In the manufacturing method of the hollow protrusion tool 1, as shown in Fig. 5(a) and Fig. 5(b), the protrusion forming step is performed in a state where the base sheet 2A is sandwiched between the first opening plate 12U and the second opening plate 12D. In the protrusion forming step, the convex mold 110 is passed through the opening 12a of the second opening plate 12D from the one side 2D side of the base sheet 2A, and then the convex mold portion 11 is brought into contact with the one side 2D of the base sheet 2A while ultrasonic vibration is generated in advance in each convex mold 110 by an ultrasonic vibration device as shown in Fig. 5(a). This softens the contact portion TP. Then, as shown in Fig. 5(b), while softening the contact portion TP, the convex mold 110 is raised from the one side 2D side of the base sheet 2A toward the other side 2U side, and the convex mold 110 is inserted into the base sheet 2A while suppressing the bending of the base sheet 2A with the first opening plate 12U arranged on the other side 2U side of the base sheet 2A. Then, minute non-penetrating hollow protrusions 3 are formed protruding from the other surface 2U side of the base sheet 2A.

[0030] From the viewpoint of forming the hollow protrusions 3, the heating temperature of the base sheet 2A by heating the convex portion 11 is preferably equal to or higher than the glass transition temperature and lower than the melting temperature of the base sheet 2A used, and particularly preferably equal to or higher than the softening temperature and lower than the melting temperature. When the base sheet 2A is heated using an ultrasonic vibration device, the temperature range is applied to the part of the base sheet 2A in contact with the convex portion 110. On the other hand, when the base sheet 2A is heated using a heater device instead of the ultrasonic vibration device, the heating temperature of the convex portion 11 may be adjusted within the above-mentioned range. The method of measuring the glass transition temperature (Tg) may be performed according to JIS K-7196 "Softening temperature test method by thermomechanical analysis of thermoplastic plastic films and sheets", which is a known method of measuring the softening temperature.

[0031] Next, in the manufacturing method of the hollow protrusion tool 1, as shown in FIG. 4 and FIG. 5(c), a cooling step is performed to cool the hollow protrusion 3 using the cold air blower 21 provided in the cooling unit 20. As shown in FIG. 4, the cold air blower 21 has an air outlet 22 for blowing cold air arranged on the other side 2U side (upper side) of the base sheet 2A, and blows cold air from the air outlet 22 to cool the non-penetrating hollow protrusion 3. The cold air blower covers the entire other side 2U side (upper side) and one side 2D side (lower side) of the belt-shaped base sheet 2A to be transported in a hollow shape, and the belt-shaped base sheet 2A is transported in the transport direction (Y direction) inside the cold air blower, and for example, the air outlet 22 for blowing cold air may be provided in the hollow. The cooling temperature and cooling time of the cold air blower 21 are controlled by a control means (not shown) provided in the manufacturing apparatus 100.

[0032] The manufacturing method of the hollow protrusion tool 1 includes a cooling step of cooling the non-penetrating hollow protrusion 3 with the convex portion 11 inserted inside the non-penetrating hollow protrusion 3. In the cooling step, the movement of the convex portion 11 in the thickness direction (Z direction) by the electric actuator (not shown) is stopped, and with the convex portion 110 of the convex portion 11 inserted inside the non-penetrating hollow protrusion 3, cold air is blown from the air outlet 22 arranged on the other surface 2U side (upper surface side) of the base sheet 2A to cool the non-penetrating hollow protrusion 3 with the convex portion 110 inserted inside the non-penetrating hollow protrusion 3.

[0033] When the heating means for the convex portion 11 is ultrasonic vibration, as in the manufacturing apparatus 100, it is not necessary to provide the cold air blower 21, and cooling can be achieved by turning off the vibration of the ultrasonic vibration device. In this respect, using ultrasonic vibration as the heating means is preferable since it simplifies the device and facilitates high-speed manufacturing of the hollow protrusion tool 1. Also, there is an advantage that heat is less likely to be transmitted to the portion of the base sheet 2A that is not in contact with the convex portion 11, and cooling is efficiently performed by turning off the application of ultrasonic vibration, so deformation is less likely to occur in areas other than the molded portion.

[0034] In the manufacturing method of the hollow protrusion tool 1, while the non-through hollow protrusion 3 is cooled in the cooling step, or after the cooling step, an opening forming step is performed to form a through hole 3h at the planned opening position of the hollow protrusion 3. In the manufacturing method shown in Figs. 4 and 5, while the non-through hollow protrusion 3 is cooled, a laser is irradiated to the planned opening position of the non-through hollow protrusion 3 using a non-contact opening means provided in the opening forming unit 40, and the through hole 3h, which is a through hole, is formed in the non-through hollow protrusion 3. In this way, when the through hole 3h is formed in the hollow protrusion 3 while cooling the non-through hollow protrusion 3, the cooling step and the opening forming step can be performed simultaneously, so that the manufacturing time can be shortened. In this embodiment, the planned opening position is the part of the hollow protrusion 3 where the laser is irradiated to form the through hole 3h.

[0035] The hole forming section 40 is provided with non-contact hole making means on the other surface 2U side of the base sheet 2A. A laser irradiation device 4 is used as the non-contact hole making means. As shown in Fig. 4, the laser irradiation device 4 has an irradiation head 41 which is a galvano scanner that freely scans a laser beam 4L. The irradiation head 41 is disposed on the other surface 2U side (upper surface side) of the base sheet 2A at a fixed distance above the other surface 2U in the thickness direction Z. In this way, when a laser beam 4L is irradiated from an irradiation head 41 arranged on the other surface 2U side (upper surface side) of the base sheet 2A onto a planned opening position of the non-penetrating hollow protrusion 3 to form a through hole 3h in the hollow protrusion 3, burrs are unlikely to be formed around the through hole 3h on the outer surface 32 of the hollow protrusion 3. In addition, since the through hole 3h can be easily formed at any position in the hollow protrusion 3, it is easy to arbitrarily control the position relative to the skin surface to which a liquid agent or the like is to be supplied.

[0036] As shown in FIG. 4, the irradiation head 41 has a lens 43 for collecting the irradiated laser beam 4L, and two mirrors 42 and a protective lens 44 for freely scanning the collected laser beam 4L. The protective lens 44 may or may not be provided, but is preferably provided in order to prevent dust and dirt from entering the optical system. The mirror 42 is attached to the motor shaft. The mirror 42 is provided with a mechanism for moving the irradiation point where the laser beam 4L hits the hollow protrusion 3 on the base sheet 2A in the conveying direction Y of the base sheet 2A and a mechanism for moving the irradiation point in the direction X perpendicular to the conveying direction of the base sheet 2A, so that the laser beam 4L can be freely scanned. The lens 43 is movable in the optical axis direction, and is provided with a mechanism for collecting the laser beam 4L to keep the spot diameter of the irradiation point of the laser beam 4L that hits the hollow protrusion 3 constant, a mechanism for moving the irradiation point of the laser beam 4L in the thickness direction Z of the base sheet 2A, and the like. The irradiation head 41 having a mirror 42 and a lens 43 can adjust the irradiation point of the laser beam 4L three-dimensionally in the X, Y, and Z directions. Therefore, by converting the desired irradiation position (nearby portion) of each of the nine hollow protrusions 3 into three-dimensional coordinates, the laser beam 4L can be irradiated with a predetermined spot diameter at the desired irradiation position of each hollow protrusion 3.

[0037] In the manufacturing method of the hollow protrusion tool 1, as shown in FIG. 5(c), in a state where the convex part 11 is inserted into the inside of the non-penetrating hollow protrusion 3, the non-penetrating hollow protrusion 3 is irradiated with a laser beam 4L from an irradiation head 41 while cooling the hollow protrusion 3 to form a through hole 3h. When the laser beam 4L is irradiated to form the through hole 3h in this manner with the convex part 11 inserted into the inside of the non-penetrating hollow protrusion 3, burrs are unlikely to form around the through hole 3h on the inner surface 31 of the hollow protrusion 3, and the agent can be stably supplied to the inside of the skin. In addition, when the laser beam 4L is irradiated to form the through hole 3h in a state where the convex part 11 is inserted into the inside of the non-penetrating hollow protrusion 3, damage is unlikely to be caused to the inner surface 31 of the side wall opposite to the side wall irradiated with the laser beam 4L in the hollow protrusion 3, and the agent can be stably supplied to the inside of the skin.

[0038] In the manufacturing method of the hollow protrusion tool 1, as shown in FIG. 5(d), in a state where the convex mold part 11 is inserted into the inside of the non-penetrating hollow protrusion part 3, a through hole 3h is formed in the non-penetrating hollow protrusion part 3, and the cooling of the hollow protrusion part 3 is stopped. Next, as shown in FIG. 5(e), a release process is performed in which the convex mold part 11 is removed from the inside of the hollow protrusion part 3 in which the through hole 3h is formed, forming a hollow protrusion part 3 with a hollow inside. If the ultrasonic vibration of the convex mold part 11 by the ultrasonic vibration device is continued in the cooling process, it is preferable to stop the ultrasonic vibration in the release process. In the release process, the convex mold part 11 is moved downward in the thickness direction (Z direction) by an electric actuator (not shown), and from a state where the convex mold 110 is inserted into the inside of each hollow protrusion part 3, the convex mold 110 is removed to form a hollow protrusion part 3 with a hollow inside. In the release process, since the second opening plate 12D is used as a deflection suppression means for suppressing deflection of the base sheet 2A when the convex portion 11 is removed from inside the hollow protrusion portion 3, the convex portion 110 can be easily removed from inside the hollow protrusion portion 3.

[0039] In the manufacturing method of the hollow protrusion tool 1, a precursor 1A of the hollow protrusion tool 1 can be manufactured in which nine hollow protrusion portions 3 are arranged on the other surface 2U (upper surface) of the base sheet 2A. After the precursor 1A of the hollow protrusion tool 1 is manufactured, the first opening plate 12U and the second opening plate 12D are separated from the base sheet 2A, and the base sheet 2A is released from the sandwiched state.

[0040] The precursor 1A of the hollow protrusion tool 1 formed as described above is then transported downstream in the transport direction Y. Thereafter, in a cutting process, it is cut to a predetermined area to produce the hollow protrusion tool 1 having a sheet-like base portion 2 and a plurality of hollow protrusion portions 3 as shown in Fig. 1. By repeating the above process, the hollow protrusion tool 1 can be produced continuously and efficiently. The hollow protrusion tool 1 manufactured as described above may be further formed into a specified shape in a subsequent process, or the base sheet 2A may be pre-adjusted to the desired shape before the process of inserting the convex portion 11.

[0041] Next, the process of forming the through-holes 3h by the laser irradiation device 4 will be described in detail. In the technology described in Patent Documents 1-3, one of the hollow protrusions is irradiated with a laser beam 4L adjusted to an output capable of forming a through hole with one irradiation. As a result, a part of the side wall of the hollow protrusion 3, which is the planned hole opening position, is melted by the thermal energy of the laser beam 4L irradiated at one time, and a through hole 3h is formed penetrating from the outer surface 32 to the inner surface 31. In addition, the irradiation position of the laser beam 4L is also one place for one hollow protrusion. For this reason, the energy of the irradiated laser beam 4L is concentrated at one place, so that a partial temperature rise is large, and with the temperature rise, a lot of heat is transmitted to the periphery of the irradiation range, and the influence of heat tends to be large in the periphery of the irradiation range. The influence of heat is thinning or thermal denaturation around the through hole of the hollow protrusion 3 due to unexpected melting. Thus, when forming a through hole 3h in a fine hollow protrusion 3 by laser irradiation (laser processing), there is a concern about insufficient strength.

[0042] That is, the part of the side wall that is to be opened by the irradiation of the laser beam 4L may melt because a hole is to be made, but if the part that is not to be opened softens or melts with an increase in temperature, the thickness of the hollow protrusion may become thin or it may become brittle and weakened due to thermal denaturation. In this way, when a hollow protrusion tool having a through hole 3h formed by one irradiation is pierced into the skin, the hollow protrusion may be damaged due to insufficient strength due to the weakening, and there is a problem in terms of maintaining the strength of the hollow protrusion. In addition, the technology of Patent Documents 1-3 does not describe the technical idea of ​​forming a through hole by heat processing while suppressing the weakening of the hollow protrusion due to irradiation by devising the number of irradiations of the laser beam 4L when forming the through hole.

[0043] Therefore, the present inventors have focused on the method of irradiating the laser beam 4L when forming the through holes 3h in the fine hollow protrusions 3. Then, in the forming step (processing step) of forming the through holes 3h, the inventors have come up with a method of irradiating the outer surface 32 of the side wall of the hollow protrusions 3 with the laser beam 4L to gradually deepen the depth of the through holes 3h, and finally forming the through holes 3h penetrating to the inner surface 31, and a method of forming openings smaller in diameter than the through holes 3h and penetrating from the outer surface 32 to the inner surface 31 of the hollow protrusions 3, the openings being smaller in diameter than the through holes 3h, and the openings being connected and integrated to form one through hole 3h. In this specification, the former will be described as a first embodiment, and the latter will be described as a second embodiment.

[0044] [First embodiment] 6(a) to 6(d) show the process of forming a through hole according to the first embodiment. In the first embodiment, a laser irradiation device 4 irradiates the hollow protrusion 3 with a laser beam 4L multiple times, the laser beam 4L having an output that does not penetrate the side wall of the hollow protrusion 3 at the intended hole opening position in one irradiation, to form a through hole 3h. In this case, the spot diameter of the laser beam 4L irradiated from the laser irradiation device 4 is set to be somewhat smaller than the dimension of the opening diameter of the designed through hole 3h on the outer surface 32. This is because the heat from the irradiation of the laser beam 4L melts the hollow protrusion 3 to a size somewhat wider than the spot diameter. When irradiating in multiple steps, the spot diameter may be the same, or the spot diameter may be changed so that the spot diameter is initially smaller than the opening diameter of the designed through hole 3h and then gradually (stepwise) increased to the spot diameter equivalent to the opening diameter of the designed through hole.

[0045] The number of times of irradiation of the laser beam 4L until the through-hole 3h is formed is preferably determined experimentally according to the material and thickness of the base sheet 2A and the wavelength [type] of the laser beam 4L. From the viewpoint of minimizing the influence of heat during irradiation, it is preferable to adjust the output and spot diameter of the laser beam 4L from the laser irradiation device 4 so that the through-hole 3h is formed by, for example, 2 to 5 irradiations. The laser beam 4L may be irradiated 10 or more times to form the through-hole 3h, but the more the number of irradiations, the longer it takes to manufacture one microneedle array, which is the hollow protrusion tool 1 equipped with the hollow protrusion portion 3 in which the through-hole 3h is formed, which is not preferable in terms of productivity. For this reason, it is preferable to limit the number of irradiations to about several times. In this embodiment, the output and spot diameter of the laser beam from the laser irradiation device 4 are adjusted so that the through-hole 3h is formed by irradiating the laser beam 4L three times as shown in FIG. 6.

[0046] When the laser beam 4L is irradiated multiple times to form the through hole 3h, it is preferable to irradiate the same position, because the same location is thermally melted each time, efficiently deepening the hole depth and shortening the time until penetration (opening). The output of the laser beam 4L for forming the through hole 3h is preferably set to an output such that the material of the planned opening position (side wall) where the through hole 3h is to be formed is melted but not penetrated by one laser irradiation. For example, assuming that the through hole 3h is formed by three irradiations of the laser beam 4L, immediately after the formation of the hollow protrusion 3 shown in Fig. 6(a), about 1 / 3 of the thickness of the side wall of the hollow protrusion 3 is melted by the first laser irradiation shown in Fig. 6(b), another 1 / 3 of the thickness of the side wall of the hollow protrusion 3 is melted by the second laser irradiation shown in Fig. 6(b), and the through hole 3h penetrating from the outer surface 32 to the inner surface 31 is formed by the third laser irradiation as shown in Fig. 6(d) (see Fig. 3). Figure 7(a) shows a view from the irradiation side of one of the hollow protrusions 3 in which a through hole 3h is formed, and Figure 7(b) is an enlarged view showing the through hole 3h formed in the hollow protrusion 3 and the affected area of ​​the surrounding area 3g.

[0047] In this way, the laser beam 4L is irradiated to the outer surface 32 of the side wall of the hollow protrusion 3 to be irradiated multiple times with an output that does not open the through hole 3h with one irradiation, and the side wall melts stepwise from the outer surface 32 to the inner surface 31 of the side wall to form the through hole 3h. Therefore, the amount of heat given to the hollow protrusion 3 per irradiation can be reduced compared to the conventional case where a through hole is formed by one irradiation. This makes it possible to reduce the heat-affected range, such as thermal denaturation due to the influence of heat and unexpected thinning, in the peripheral portion 3g where the through hole 3h is formed by being irradiated with the laser beam 4L. In other words, since the thermal effect caused by the irradiation of the laser beam 4L when the through hole is formed in the hollow protrusion 3 is reduced, it is possible to suppress the peripheral portion 3g of the through hole 3h from being weakened, and it is possible to provide a hollow protrusion tool 1 that maintains its strength. In the embodiment, the opening diameter r1 of the through hole 3h is the width of the through hole 3h in the width direction (X direction) perpendicular to the thickness direction Z which is the protruding direction of the hollow protrusion 3, as shown in Fig. 7(b). Also, the diameter r2 of the peripheral portion (heat-affected portion) 3g which is the range affected by heat is the width of the peripheral portion 3g which is the range affected by heat in the width direction (X direction). By irradiating the laser beam 4L multiple times as in the present embodiment, the diameter r2 of the peripheral portion 3g can be made smaller than that of the conventional configuration. In measuring the width of the peripheral portion 3g affected by heat that is formed around the through hole 3h by laser irradiation, the discolored portion around the through hole 3h, or the inclined side portion when the shape of the through hole 3h is considered to be a truncated cone, is defined as the portion that has been thinned by heat, compared to the outer surface 32 of the hollow protrusion portion 3 that is not affected by heat, and the periphery of the bottom surface of the truncated cone is defined as the peripheral portion 3g affected by heat. The width of the peripheral portion 3g can be measured using a microscope or scanning electron microscope (SEM) to determine the value of the diameter r2 of the peripheral portion 3g.

[0048] Second Embodiment 8(a) to 8(d) show the process of forming the through hole 3h according to the second embodiment. In the second embodiment, the through hole 3h is formed by irradiating the outer surface 32 of the hollow protrusion 3 with a laser beam 4L having an output that penetrates the hollow protrusion 3 with a smaller aperture diameter r1 than the aperture diameter r1 of the through hole 3h in one irradiation multiple times. In this case, the spot diameter of the laser beam 4L irradiated from the laser irradiation device 4 is smaller than the dimension of the opening diameter of the designed through hole 3h on the outer surface 32 of the hollow protrusion 3, and the output of the laser beam 4L is set to an output that penetrates (the side wall) from the outer surface 32 to the inner surface 31 in one irradiation. In addition, in this embodiment, the spot diameter of the laser beam 4L is set to be larger with each irradiation. When the spot diameter is increased, if the laser output remains the same as before the spot diameter was changed, it is assumed that the amount of irradiation energy per unit area will decrease and the hollow protrusion 3 will not be penetrated. For this reason, in this embodiment, the laser output is increased as the spot diameter increases, so that it is possible to reliably penetrate an opening diameter smaller than the designed diameter in one irradiation.

[0049] For example, assuming that the through hole 3h is formed by irradiating the laser beam 4L three times, the first laser irradiation shown in FIG. 8(b) immediately after the formation of the hollow protrusion 3 shown in FIG. 8(a) forms an opening 301 that penetrates the side wall of the hollow protrusion 3 with a smaller diameter than the through hole 3h, and the second laser irradiation shown in FIG. 8(c) irradiates the opening 301 with a high output laser beam 4L that is larger than the spot diameter of the first irradiation to form an opening 302 that penetrates with a larger diameter than the opening 301. As shown in FIG. 8(d), the third laser irradiation irradiates the opening 302 with a high output laser beam 4L that is larger than the spot diameter of the second irradiation to form an opening 303 that penetrates with a larger diameter than the opening 302. In this embodiment, this opening 303 becomes the through hole 3h shown in FIG. 9(a).

[0050] When the through-holes 3h are formed by multiple irradiation with the laser beam 4L that forms an opening with a smaller diameter than the designed dimension of the through-hole 3h as in the second embodiment, the through-holes 3h may be formed by multiple irradiation at adjacent positions on the same surface of the hollow protrusion 3. In this case, the output and spot diameter of the laser beam for each irradiation are the same, and only the irradiation position is changed. For example, when the through-hole 3h is formed by irradiating the laser beam 4L three times, the laser beam 4L is irradiated three times so as to trace the locus of the vertices of a triangle (an equilateral triangle is shown in FIG. 9(b)) on the outer surface 32. In this case, the irradiation positions are adjusted so that the opening 301 formed by the first laser irradiation, the opening 302 formed by the second laser irradiation, and the opening 303 formed by the third laser irradiation are formed adjacent to each other. The symbol P in the figure indicates the center-to-center distance of the spot diameter P1.

[0051] In this way, when the laser beam 4L, which penetrates the hollow protrusion 3 in one irradiation but has a diameter smaller than the through hole 3h, is irradiated to adjacent portions on the same surface of the outer surface 32, the openings 301-303 formed by the irradiation of each laser beam 4L melt and connect due to the heat. Therefore, as shown by the dashed line in Figure 9(b), the through hole 3h larger than the spot diameter P1 of the laser beam 4L can be formed with less thermal influence, and the weakening of the surrounding portion 3g of the through hole 3h can be suppressed, making it possible to provide a hollow protrusion tool 1 that maintains its strength.

[0052] When forming the through hole 3h by irradiating the hollow protrusion 3 with a laser beam 4L multiple times, the diameter of which is smaller than that of the through hole 3h, the laser beam 4L may be irradiated so that at least two of the openings 301, 302, and 303 overlap each other, so that they are connected and integrated to form one through hole 3h, as shown in Fig. 9(c). Even in this way, the through hole 3h larger than the spot diameter P1 of the laser beam 4L can be formed with less thermal influence, and the same effect as above can be achieved.

[0053] In the first and second embodiments, one through hole 3h is formed for one hollow protrusion 3, but the number of through holes 3h may be multiple, as shown in Figures 10(a) and (b), for one hollow protrusion 3. Fig. 10(a) shows a configuration in which two through holes 3h are formed side by side in the protruding direction (thickness direction Z) of the hollow protrusion 3, and Fig. 10(b) shows a configuration in which a plurality of through holes 3h are formed so as to be line-symmetrical with respect to a center line CL passing through the center of the tip end of the hollow protrusion 3. In Fig. 10(b), the through holes 3h are each formed in an outer surface 32, which is a portion located in the width direction (X direction) of the hollow protrusion 3. When forming a plurality of through holes 3h in the protruding direction (thickness direction Z) as shown in Fig. 10(a), they can be formed by, for example, controlling the irradiation head 41 to change the irradiation position of the laser beam 4L in the protruding direction (thickness direction Z). When forming one through hole 3h in each width direction (X direction) as shown in Fig. 10(b), after the through holes 3h are formed on one side of all the hollow protrusions 3, the orientation of the hollow protrusion tool 1 may be rotated 180 degrees and the through hole 3h may be formed on the other side by the laser irradiation device 4. By forming a plurality of through holes 3h in this manner, it is possible to adjust the supply speed of the agent contained in the space 3k of the hollow protrusion portion 3. Furthermore, when a plurality of through holes 3h are formed in the thickness direction Z, it is possible to supply the agent to different skin layers when the microarray (hollow protrusion tool 1) is punctured into the skin.

[0054] It is preferable to use a laser beam 4L that can be absorbed by the hollow protrusions 3 as the laser beam 4L for forming the through holes 3h. When the base sheet 2A for forming the hollow protrusions 3 is a sheet such as a film mainly made of a thermoplastic resin, the laser beam 4L is preferably CO 2 Laser, Excimer laser, Argon laser, YAG laser, LD laser (semiconductor laser), YVO 4 It is preferable to use a UV laser, a fiber laser, or the like. In other words, from the viewpoint of reducing the thermal effects, and from the viewpoints of the introduction and handling of laser equipment and productivity, the wavelength of the laser beam 4L is 180 nm or more, preferably 300 nm or more, more preferably 350 nm or more, and preferably 20 μm or less, more preferably 12 μm or less, preferably 180 nm or more and 20 μm or less, and more preferably 350 nm or more and 12 μm or less.

[0055] From a similar viewpoint, the pulse width of the laser beam 4L is 1 fs or more, preferably 100 fs or more, more preferably 1000 fs or more, and 10 ms or less, preferably 5 ms or less, more preferably 1 ms or less, preferably 1 fs or more and 10 ms or less, more preferably 100 fs or more and 5 ms or less, and more preferably 1000 fs or more and 1 ms or less.

[0056] Although a through hole 3h may be formed at the tip of the hollow protrusion 3, from the viewpoint of maintaining the strength of the tip of the hollow protrusion 3 and the sharp shape to facilitate puncturing the skin, it is preferable that in the step of forming the through hole 3h, the laser beam 4L is irradiated to a position shifted from the center of the tip of the non-penetrating hollow protrusion 3 to form the through hole 3h, and the laser irradiation is not affected by the tip of the hollow protrusion 3. From the viewpoint of forming the through hole 3h by irradiating the inclined side wall of the hollow protrusion 3 with a small irradiation energy, from the viewpoint of reducing the area irradiated with the laser beam 4L and suppressing the influence of the irradiation energy to maintain the strength around the formed through hole 3h, and from the viewpoint of reducing the influence of the laser irradiation on the adjacent hollow protrusions, in the step of forming the through hole, as shown in FIG. 5(c), it is preferable to form the through hole 3h by irradiating the non-penetrating hollow protrusion 3 with the laser beam 4L from the irradiation head 41 of the laser irradiation device 4 in a direction ILf inclined with respect to the piercing direction ILe of the convex mold 110 of the convex mold part 11.

[0057] From the same viewpoint, the angle θ between the insertion direction ILe of the convex mold 110 and the inclined direction ILf in which the laser beam 4L is irradiated is preferably 5 degrees or more, more preferably 10 degrees or more, particularly preferably 15 degrees or more, and is preferably 85 degrees or less, more preferably 80 degrees or less, and particularly preferably 75 degrees or less. Specifically, it is preferably 5 degrees or more and 85 degrees or less, more preferably 10 degrees or more and 80 degrees or less, and particularly preferably 15 degrees or more and 75 degrees or less.

[0058] From the viewpoint of forming a through hole in the hollow protrusion 3 and reducing thermal effects, the irradiation time of the laser beam 4L is preferably 0.1 ms or more, more preferably 0.5 ms or more, and preferably 100 ms or less, more preferably 70 ms or less, and specifically, preferably 0.1 ms or more and 100 ms or less, and more preferably 0.5 ms or more and 70 ms or less.

[0059] From a similar viewpoint, the laser output of the laser beam 4L is preferably 0.5 W or more, more preferably 1 W or more, and is preferably 100 W or less, more preferably 50 W or less, and specifically, is preferably 0.5 W or more and 100 W or less, and more preferably 1 W or more and 50 W or less.

[0060] The thickness of the intended opening positions of the hollow protrusions 3 is at least 0.01 mm, preferably 0.02 mm or more, and 0.7 mm or less, preferably 0.5 mm or less, which is desirable because by irradiating the thermoplastic resin of the base sheet 2A multiple times, the thermal effects can be more significantly reduced and the strength required for the hollow protrusions 3 to puncture the skin can be obtained.

[0061] The ultraviolet transmittance when the base sheet 2A forming the hollow protrusions 3 is irradiated with a laser beam is 60% or more, preferably 65% ​​or more, more preferably 70% or more, and 95% or less, preferably 90% or less, and specifically, 60% or more and 95% or less, more preferably 65% ​​or more and 90% or less, and even more preferably 70% or more and 90% or less. In other words, the hollow protrusions 3 are preferably formed from a material with an ultraviolet transmittance of 60% or more and 95% or less. When the ultraviolet transmittance is within this range, the thermal effect caused by excessive transmission of laser energy to the hollow protrusions 3 is suppressed, and processing can be performed with high precision.

[0062] In the above embodiment, after the protrusion processing step in which a convex portion 11 for forming a protrusion is inserted into one side of a sheet-like base portion 2 serving as a substrate formed containing a thermoplastic resin to form a non-through hollow protrusion portion 3 protruding from the other side of the base portion 2, a laser beam 4L is irradiated multiple times onto the hollow protrusion portion 3 to form a through hole 3h, so that a hollow protrusion tool 1 having continuous through holes 3h can be formed after the protrusion processing step. Furthermore, by manufacturing the hollow protruding tool 1 having the fine hollow protruding portion 3 with the through hole 3h by using the above manufacturing method, it is possible to maintain the strength.

[0063] As described above, according to the manufacturing method of this embodiment using the manufacturing apparatus 100 for manufacturing the hollow protrusion device 1, a protrusion forming process includes inserting a convex portion 11 from one surface 2D of a base sheet 2A to form a fine non-through hollow protrusion 3 that protrudes from the other surface 2U of the base sheet 2A, and a formation process for forming a through hole 3h by irradiating a laser beam 4L from a laser irradiation device 4 multiple times onto the non-perforated hollow protrusion 3, so that the magnitude of the thermal effect is minimized and a hollow protrusion device 1 with ensured strength can be manufactured.

[0064] Although the present invention has been described based on the preferred embodiment, the present invention is not limited to the embodiment and can be modified as appropriate. For example, in the manufacturing method of the hollow protrusion tool 1, the convex mold portion 11 is inserted into the inside of the non-penetrating hollow protrusion 3, and the hollow protrusion 3 is cooled in the cooling process, while the through hole 3h is formed in the hollow protrusion 3 using the laser irradiation device 4. However, after the convex mold portion 11 is removed from the inside of the non-penetrating hollow protrusion 3, the through hole 3h may be formed in the non-penetrating hollow protrusion 3 using the laser irradiation device 4. Specifically, as shown in Fig. 11(a) and Fig. 11(b), in a state where the base sheet 2A is sandwiched between the first opening plate 12U and the second opening plate 12D, the convex mold 110 is passed through the opening 12a of the second opening plate 12D from the one surface 2D side of the base sheet 2A, and the convex mold portion 11 is brought into contact with the one surface 2D of the base sheet 2A while the ultrasonic vibration device generates ultrasonic vibration in advance in each convex mold 110. This softens the contact portion TP while raising the convex mold 110 from one surface 2D side toward the other surface 2U side of the base sheet 2A, forming a non-penetrating hollow protrusion 3 protruding from the other surface 2U side of the base sheet 2A.

[0065] 11(c), the non-penetrating hollow protrusion 3 is cooled using a cold air blower 21 arranged on the other surface 2U side (upper surface side) of the base sheet 2A. Then, a release process is performed in which the convex portion 11 is removed from the inside of the non-penetrating hollow protrusion 3 to form a hollow protrusion 3 with a hollow interior. In the release process, the ultrasonic vibration of the convex portion 11 by the ultrasonic vibration device is stopped, the convex portion 11 is moved downward in the thickness direction (Z direction) by an electric actuator (not shown), and the convex portion 110 is removed from the inside of the hollow protrusion 3 while suppressing the bending of the base sheet 2A by the second opening plate 12D, to form the non-penetrating hollow protrusion 3.

[0066] Next, after cooling, as shown in Figure 11(d), a laser beam 4L is irradiated from an irradiation head 41 of a laser irradiation device 4 arranged on the other surface 2U side (upper surface side) of the base sheet 2A to the non-penetrating hollow protrusion 3 to form a through hole 3h, and as shown in Figure 11(e), a hollow protrusion 3 with a through hole 3h formed therein may be formed. In the above-mentioned method for manufacturing the hollow protruding tool 1, an ultrasonic vibration device is used as the heating means for each convex portion 11, but the heating means for the convex portion 11 may be a heater device. EXAMPLES

[0067] The present invention will be described in more detail below with reference to examples, but the scope of the present invention is not limited to these examples.

[0068] 1. Preparation of the laser device installed in the manufacturing equipment The laser irradiation device 4 for forming the through hole 3h is a CO 2 A CO laser with a wavelength of 9.3 μm was used. 2 We prepared one that irradiated laser beam 4L and another that irradiated UV laser beam 4L with a wavelength of 355 nm using a UV laser device. 2. Preparation of Base Sheet 2A As the base sheet 2A, a strip-shaped sheet of polylactic acid (PLA; Tg 55.8° C.) having a thickness of 0.4 mm was prepared. 3. Formation of non-penetrating hollow protrusions A non-penetrating hollow protrusion 3 was formed in the order shown in Fig. 6(a) to Fig. 6(c). The forming conditions were that the amplitude of the ultrasonic vibration of the convex portion 11 was 70%, the insertion height of the convex portion 11 was 1.4 mm, and the insertion speed was 2 mm / sec. The softening time was 0.3 seconds, and the cooling time was 1.0 second. The protruding height H1 of the formed hollow protrusion 3 was 1 mm (1000 µm).

[0069] Example 1 Table 1 shows the measurement conditions and the measurement results for Example 1 and Comparative Example 1. After forming the non-penetrating hollow protrusion 3, the through hole 3h was formed by the forming step in the manufacturing method of the first embodiment. 2The laser output of the laser beam 4L from the laser device was fixed at 3.2 W, the angle θ between the insertion direction ILe and the inclined direction ILf was fixed at 30 degrees, and the laser beam 4L was irradiated nine times onto the hollow protrusion 3 to form a through hole 3h with an opening diameter (through hole diameter) r1 of 40 μm. At this time, the diameter (heat-affected diameter) r2 of the surrounding portion 3g affected by heat formed around the through hole 3h by the laser irradiation was 120 μm, and the ratio of the heat-affected diameter / through hole diameter was 3.00. The aperture diameter and the heat-affected diameter were measured using a microscope (Keyence VHX-5000, lens magnification 200x). In measuring the peripheral portion 3g affected by heat formed around the through hole 3h by laser irradiation, the inclined side portion when the shape of the through hole 3h is considered to be a truncated cone is defined as the portion that has been thinned by the heat, and the periphery of the bottom surface of the truncated cone shape is considered to be the peripheral portion 3g affected by heat. The width of the peripheral portion 3g was measured using a microscope to obtain the value of r2.

[0070] Comparative Example 1 As shown in Table 1, the non-penetrating hollow protrusion 3 was formed in the same manner as in Example 1, the laser output of the laser beam 4L was fixed at 9.7 W, the angle θ between the insertion direction ILe and the inclined direction ILf was fixed at 30 degrees, and the laser beam 4L was irradiated once onto the hollow protrusion 3 to form a through hole 3h with an opening diameter (through hole diameter) r1 of 40 μm. At this time, the diameter (heat-affected diameter) r2 of the surrounding portion 3g affected by heat formed around the through hole 3h by the laser irradiation was 182 μm, and the ratio of the heat-affected diameter / through hole diameter was 4.55. In other words, when forming through holes 3h of the same diameter in hollow protrusion 3 using laser beam 4L, the diameter r2 of the surrounding portion 3g can be clearly smaller when forming through holes 3h by irradiating laser beam 4L multiple times from laser irradiation device 4 with a laser beam 4L of an output that does not penetrate adjacent portions of hollow protrusion 3 in a single irradiation than when forming through holes 3h by irradiating laser beam 4L of an output that penetrates adjacent portions of hollow protrusion 3 in a single irradiation from laser irradiation device 4.

[0071] [Table 1]

[0072] Example 2 Table 2 shows the measurement conditions and the measurement results for Example 2 and Comparative Example 2. After forming the non-penetrating hollow protrusion 3, the through hole 3h was formed by the irradiation process in the manufacturing method of the first embodiment. Specifically, the position from the tip of the hollow protrusion 3 was fixed at 300 μm, the laser output of the laser beam 4L from the UV laser device was fixed at 1.75 W, the angle θ between the insertion direction ILe and the inclined direction ILf was fixed at 30 degrees, and the laser beam 4L was irradiated four times at the same location on the outer surface 32 that is the adjacent part of the hollow protrusion 3 with an irradiation time of 0.5 ms per irradiation to form the through hole 3h. At this time, the opening diameter (through hole diameter) r1 of the through hole 3h formed by the laser irradiation was 20 μm, the diameter (heat-affected diameter) r2 of the surrounding part 3g affected by heat formed around this through hole 3h was 50 μm, and the ratio of the heat-affected diameter / through hole diameter was 2.50.

[0073] Comparative Example 2 The non-penetrating hollow protrusion 3 was formed in the same manner as in Example 1, and the laser output of the laser beam 4L from the UV laser device was fixed at 1.75 W, the angle θ between the insertion direction ILe and the inclined direction ILf was fixed at 30 degrees, and the laser beam 4L was irradiated once to the outer surface 32 of the hollow protrusion 3 with a single irradiation time of 30 μm to form a through hole 3h. At this time, the opening diameter (through hole diameter) r1 of the through hole 3h formed by the laser irradiation was 30 μm, and the diameter (heat-affected diameter) r2 of the peripheral portion 3g affected by heat formed around this through hole 3h was 80 μm, and the ratio of the heat-affected diameter / through hole diameter was 2.67. In other words, when forming through holes 3h of the same diameter in hollow protrusion 3 using laser beam 4L, the diameter r2 of the surrounding portion 3g can be clearly smaller when forming through holes 3h by irradiating laser beam 4L multiple times from laser irradiation device 4 with a laser beam 4L of an output that does not penetrate adjacent portions of hollow protrusion 3 in a single irradiation than when forming through holes 3h by irradiating laser beam 4L of an output that penetrates adjacent portions of hollow protrusion 3 in a single irradiation from laser irradiation device 4. The opening diameter r1 of the through-hole 3h and the diameter r2 of the peripheral portion 3g affected by the heat can be measured using a microscope or a scanning electron microscope (SEM).

[0074] [Table 2]

[0075] Table 3 shows the measurement conditions and results of Examples 3 and 4. In Examples 3 and 4, through holes 3h were formed using the second embodiment, in which a laser beam 4L having an output that penetrates through a hole diameter smaller than the hole diameter of the through hole 3h in one irradiation is irradiated multiple times onto adjacent locations on the same surface of the hollow protrusion 3, thereby forming the through hole 3h. Example 3 After forming the non-penetrating hollow protrusion 3, the through holes 3h were formed by the irradiation process in the manufacturing method of the second embodiment. Specifically, the position from the tip of the hollow protrusion 3 was fixed to 300 μm, the laser output of the laser beam 4L from the UV laser device was fixed to 1.75 W, and the angle θ between the insertion direction ILe and the inclined direction ILf was fixed to 30 degrees. The laser beam 4L was irradiated three times at different positions on the outer surface 32, which is the same surface of the hollow protrusion 3, with each irradiation time being 5 ms. light The through hole 3h was formed with a total irradiation time of 15 ms. The spot diameter of the laser beam 4L was the same during the three irradiations. Here, the aperture diameter (through hole diameter) r1 of the through hole 3h was set to 40 μm, so one spot diameter was set to 25 μm, which is smaller than 40 μm. The three spot diameters were circular, and irradiation was performed so that each spot diameter was adjacent to each other. When the diameter (heat-affected diameter) r2 of the surrounding portion 3g affected by heat formed around the through hole 3h at this time was measured, it was 70 μm, and the ratio of the heat-affected diameter / through hole diameter was 1.75.

[0076] Example 4 After forming the non-penetrating hollow protrusion 3, the through hole 3h was formed by the irradiation step in the manufacturing method of the second embodiment. Specifically, the position from the tip of the hollow protrusion 3 was fixed at 300 μm, the laser output of the laser beam 4L from the UV laser device was fixed at 1.75 W, the angle θ between the insertion direction ILe and the inclined direction ILf was fixed at 30 degrees, and the laser beam 4L was irradiated twice at different locations on the outer surface 32 that is the same surface of the hollow protrusion 3 with an irradiation time of 45 ms each time, and the through hole 3h was formed with a total irradiation time of 90 ms. The spot diameter of the laser beam 4L was irradiated with the same diameter during the two irradiations. Here, the opening diameter (through hole diameter) r1 of the through hole 3h was set to 40 μm, so one of the multiple spot diameters was set to 25 μm, which is smaller than 40 μm. The two spot diameters were circular, and irradiation was performed so that the spot diameters were adjacent to each other. At this time, the diameter (heat-affected diameter) r2 of the peripheral portion 3g affected by the heat formed around the through hole 3h was measured to be 102 μm, and the ratio of the heat-affected diameter / through hole diameter was 2.55. The heat-affected diameter and the through hole diameter were measured using a microscope (Keyence VHX-5000, lens magnification 200x) as in Examples 1 and 2.

[0077] In other words, when forming through holes 3h of the same diameter in hollow protrusion 3 using laser beam 4L, the measurement results showed that the diameter r2 of the heat-affected zone was clearly smaller when forming through holes 3h by irradiating outer surface 32 of hollow protrusion 3 multiple times with laser beam 4L from laser irradiation device 4, the diameter having an output sufficient to penetrate a nearby portion of hollow protrusion 3 in a single irradiation. The shapes of the through holes 3h formed in Example 3 and Example 4 are different. That is, in Example 3, the laser beam 4L is irradiated so that the centers of the spot diameters are located at the vertices of an equilateral triangle and the spot diameters are adjacent to each other or overlap, thereby forming openings with a smaller diameter than the through holes 3h, which are connected and integrated to form one through hole 3h. In Example 3, the through holes 3h are substantially circular. In contrast, in the case of Example 4, the laser beam 4L is irradiated so that the spot diameter is arranged side by side adjacent to each other in the width direction (X direction) that intersects with the protruding direction of the hollow protrusion 3, and openings having a smaller diameter than the through hole 3h are formed, and these openings are connected and integrated to form one through hole 3h. In the case of Example 4, the through hole 3h is elongated horizontally and extends in the width direction (X direction). It is preferable that the irradiation position and number of the laser beams 4L are determined according to the size and shape of the through-hole 3h that is ultimately desired to be formed.

[0078] [Table 3]

[0079] In this way, when a thermoplastic is used as the material for the base sheet 2A, the output of one irradiation does not melt the base sheet 2A to penetrate, but multiple irradiations cause the base sheet 2A to melt and form the through-holes 3h, which reduces the amount of heat given to the base sheet 2A (hollow protrusions 3) by one irradiation, compared to forming the through-holes 3h by one irradiation. Therefore, the range of the surrounding area 3g (heat-affected area) affected by the heat from the irradiation can be reduced, and the strength of the hollow protrusions 3 can be maintained.

[0080] On the other hand, in the case of the second embodiment, when multiple apertures smaller in diameter than through hole 3h are formed on the same surface and the individual holes are melted and connected to become one to form through hole 3h, the output per unit area can be increased by narrowing the spot diameter, and an aperture smaller in diameter than through hole 3h can be formed that penetrates through an adjacent portion of hollow protrusion 3. In this way, holes are formed that penetrate the fine hollow protrusions 3, but by making the diameter of the holes smaller than the through-holes 3h, the amount of heat given to the base sheet 2A by one irradiation can be reduced. Therefore, the area affected by the heat from the irradiation can be made smaller than the through-holes 3h, and the hollow protrusions 3 can be manufactured while maintaining their strength. [Explanation of symbols]

[0081] 1 hollow protrusion 2 Base 2A Base sheet One side of 2D base sheet 2U Other side of base sheet 3 Hollow protrusion 3h through hole 4. Laser irradiation device 4L Laser beam 11 Convex part 32 Proximal area (outer surface) r3 Diameter of the hole formed on the inside r1: Diameter of the outer opening T2 substrate thickness CL center line

Claims

1. A method for manufacturing a hollow protrusion tool, comprising a hole forming step of forming a through hole in a fine hollow protrusion portion, The hollow protrusion is mainly made of a thermoplastic resin, and the thickness of the intended hole opening position is 0.01 mm or more and 0.7 mm or less. A method for manufacturing a hollow protrusion tool, in which the through hole is formed by irradiating adjacent portions of the same surface of the hollow protrusion with a laser beam of an output that penetrates the hollow protrusion with an opening diameter smaller than the opening diameter of the through hole in a single irradiation.

2. A method for manufacturing a hollow protrusion tool, comprising a hole forming step of forming a through hole in a fine hollow protrusion portion, a laser beam having an output capable of penetrating the hollow protrusion with an opening diameter smaller than the opening diameter of the through hole in a single irradiation is irradiated a plurality of times at mutually adjacent portions on the same surface of the hollow protrusion, thereby forming the through hole; The method for manufacturing a hollow-projection tool, wherein the multiple irradiations are performed so that the spot diameters are adjacent to each other or overlap each other.

3. The method for manufacturing a hollow protrusion tool according to claim 1 or 2, wherein the through hole is formed by irradiating the laser beam a plurality of times so as to trace a locus of vertices of a triangle.

4. The method for manufacturing a hollow protrusion tool according to any one of claims 1 to 3, wherein the wavelength of the laser beam is 180 nm or more and 20 µm or less.

5. The method for manufacturing a hollow protrusion tool according to any one of claims 1 to 4, wherein the pulse width of the laser beam is not less than 1 fs and not more than 10 ms.

6. The method for manufacturing a hollow protrusion tool according to any one of claims 1 to 5, wherein the through hole is formed such that the aperture diameter formed on the outside of the hollow protrusion is larger than the aperture diameter formed on the inside of the hollow protrusion by irradiating the laser beam to the hollow protrusion multiple times from the outside of the hollow protrusion.

7. The method for manufacturing a hollow protrusion tool according to any one of claims 1 to 6, wherein the hollow protrusion portion is formed from a material having an ultraviolet ray transmittance of 60% or more and 95% or less.

8. The method for manufacturing a hollow protrusion tool according to any one of claims 1 to 7, wherein the through hole is formed by performing the hole forming process after a protrusion processing process in which a convex portion for forming a protrusion is inserted from one side of a base sheet to form the hollow protrusion protruding from the other side of the base sheet.

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