JP2024019686A - Method for manufacturing hollow protrusions and hollow protrusions - Google Patents

Abstract

An object of the present invention is to provide a hollow protrusion that maintains strength by suppressing weakening of the surrounding area of a through hole formed in a fine hollow protrusion. [Solution] A method for manufacturing a hollow protrusion 1, which includes a hole forming step of forming a through hole 3h in a fine hollow protrusion 3, in which the hollow protrusion 3 is irradiated once. A through hole 3h is formed by irradiating a laser beam with an output power that penetrates the protrusion 3 with an aperture diameter smaller than the aperture diameter of the through hole 3h to mutually adjacent regions on the same surface of the hollow protrusion 3 multiple times. do. [Selection diagram] Figure 5

Description

The present invention relates to a method for manufacturing a hollow protrusion and a hollow protrusion.

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

JP 2019-50927 Publication International Publication No. 2015/125475 Japanese Patent Application Publication No. 2011-72695

The techniques described in Patent Documents 1 to 3 do not take into account that when forming a through hole in a hollow protrusion with a laser beam, the surrounding area of the through hole becomes weakened due to the influence of the heat of the laser beam. There is an issue with the strength of the parts.

Therefore, an object of the present invention is to provide a method for manufacturing a hollow protrusion and a hollow protrusion that can solve the problems of the prior art described above.

The present invention is a method for manufacturing a hollow protrusion tool, which includes a hole forming step of forming a through hole in a minute hollow protrusion, the hollow protrusion being formed with a laser beam, which is a non-contact perforation means. The present invention provides a method for manufacturing a hollow protrusion, in which the through hole is formed by irradiating a plurality of times from an irradiation device with a laser beam having an output that does not penetrate the planned opening position of the hollow protrusion in one irradiation. be.
The present invention is a method for manufacturing a hollow protrusion, which includes a hole forming step of forming a through hole in a minute hollow protrusion, and the hollow protrusion is irradiated once to the hollow protrusion. A hollow protrusion tool that forms the through hole by irradiating mutually adjacent parts of the same surface of the hollow protrusion multiple times with a laser beam having an output that penetrates with an aperture diameter smaller than the aperture diameter of the through hole. The present invention provides a method for manufacturing.
The present invention provides a hollow protrusion having a fine hollow protrusion having a through hole, which is manufactured by any of the manufacturing methods described above.

According to the present invention, the thermal effect caused by the laser beam irradiation when forming the through hole in the hollow protrusion is reduced, so that the surrounding area of the through hole can be prevented from becoming brittle, and the strength of the hollow protrusion can be maintained. Therefore, it is possible to provide a hollow protrusion that suppresses deformation of the hollow protrusion when puncturing the skin, and which is easy to puncture the skin.

FIG. 1 is a perspective view schematically showing an example of a hollow protrusion manufactured by the method for manufacturing a hollow protrusion of the present invention, in which fine hollow protrusions having through holes are arranged. FIG. 2 is an enlarged perspective view of the hollow protrusion, focusing on one of the plurality of hollow protrusions shown in FIG. 1. FIG. FIG. 3 is a sectional view taken along the line III--III shown in FIG. FIG. 4 is a diagram showing the overall configuration of a manufacturing apparatus used in a preferred embodiment for manufacturing the hollow protrusion shown in FIG. 1. FIGS. 5A to 5E are diagrams illustrating a manufacturing method for manufacturing a hollow protrusion having a fine hollow protrusion having a through hole using the manufacturing apparatus shown in FIG. FIGS. 6(a) to 6(d) are diagrams showing the process of forming such a through hole in the first embodiment of the present invention. FIG. 7(a) is an enlarged view of a hollow protrusion in which a through hole is formed by the manufacturing method according to the first embodiment, viewed from the irradiation side, and FIG. FIG. 3 is an enlarged view showing a peripheral area affected by heat. FIGS. 8(a) to 8(d) are diagrams showing the process of forming such a through hole in the second embodiment of the present invention. FIG. 9(a) is an enlarged view of a state in which a plurality of openings having a diameter smaller than that of the through-hole are formed by the manufacturing method according to the second embodiment, as seen from the irradiation side. A partially enlarged view showing the step of forming a through hole by moving the laser beam irradiation position to the apex position of the triangle, FIG. 9(c) shows the step of forming a through hole by overlapping a plurality of penetrating holes. It is a partially enlarged view. FIG. 10(a) is an enlarged view illustrating a configuration in which a plurality of through holes are arranged adjacent to each other in the protruding direction of a hollow protrusion, and FIG. 10(b) is an enlarged view illustrating a configuration in which a plurality of through holes are formed line-symmetrically. FIG. FIG. 11 is a diagram illustrating another embodiment of a manufacturing method for manufacturing the hollow protrusion shown in FIG. 1.

Hereinafter, the present invention will be explained 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 having a hollow interior. FIG. 1 shows a perspective view of a fine hollow protrusion 1 according to an embodiment manufactured by a method for manufacturing a fine hollow protrusion according to an embodiment. The hollow protrusion 1 has a base portion 2 that is a flat sheet-like base material, and a plurality of fine hollow protrusions 3. Although there are no particular restrictions on the number of hollow protrusions 3, the arrangement of hollow protrusions 3, and the shape of hollow protrusions 3, the hollow protrusions 1 of this embodiment preferably have a sheet-like base 2. The upper surface has nine truncated conical hollow protrusions 3 arranged in an array (matrix). The nine hollow projections 3 arranged in an array (matrix) form three rows in the Y direction, which is the direction in which the base sheet 2A (vertical direction of the base sheet 2A) is conveyed, which will be described later, and perpendicular to the conveying direction. They are arranged in three rows in the X direction, which is the lateral direction of the base sheet 2A being conveyed.

2 is a perspective view of the hollow protrusion 1 focusing on one of the arranged hollow protrusions 3 of the hollow protrusion 1, and FIG. 3 is a perspective view of the hollow protrusion 1 shown in FIG. It is a sectional view taken along line III. The hollow protrusion 1 is a so-called microneedle array, and by pressing the hollow protrusion 3 against the skin and puncturing it, the agent sealed inside the hollow protrusion 3 is delivered to the skin through the through hole 3h. It supplies the inside of the The microneedle array is an example of the hollow protrusion 1, and the hollow protrusion 1 is not limited to the microneedle array.

As shown in FIG. 2, the hollow protrusion 1 has a through hole 3h in the hollow protrusion 3. As shown in FIG. 3, the hollow protrusion 1 has base-side openings 2h at positions corresponding to the respective hollow protrusions 3 in the base portion 2. The hollow protrusion 1 has a space 3k extending from the base-side opening 2h of the base portion 2 through the inside of each hollow protrusion 3 to the tip-side through-hole 3h. Therefore, the through hole 3h is formed to penetrate from the outside of the hollow protrusion 3 to the internal space 3k. The space 3k inside each hollow protrusion 3 is formed in a shape corresponding to the outer shape of the hollow protrusion 3, and in the hollow protrusion 1 shown in FIG. It is shaped like a corresponding cone. The hollow protrusion 3 has a conical outer shape, but in addition to the conical shape, the hollow protrusion 3 may have a truncated conical shape, a cylindrical shape, a prismatic shape, a pyramid shape, a truncated pyramid shape, etc.

As shown in FIG. 2, the through hole 3h is an opening formed at a planned opening position shifted from the center of the tip of the hollow protrusion 3. If the through hole 3h is formed at a position offset from the center of the tip of the hollow protrusion 3, the through hole 3h will not be easily crushed when the hollow protrusion 3 is punctured into the skin, and the through hole 3h will pass through the skin. The agent can be stably supplied from the hollow protrusion 1 into the inside of the tube.

When each hollow protrusion 3 is used as a microneedle, the protrusion height H1 ( (see FIG. 3) is defined as follows in this embodiment. The protrusion height H1 is preferably 0.01 mm or more, more preferably 0.02 mm or more, and preferably 10 mm or less, still more preferably 5 mm or less, and specifically, preferably 0.01 mm. It is 10 mm or more, more preferably 0.02 mm or more and 5 mm or less.

As shown in FIG. 7(b), the through hole 3h is formed closer to the outer surface 32 of the hollow protrusion 3 than the opening area S2 of the aperture diameter r3 formed inside the inner surface 31 of the hollow protrusion 3. The aperture area S1 of the aperture diameter r1 is formed larger. That is, the through hole 3h is formed so 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. This is the diameter at the widest position.
From the viewpoint of stably supplying the agent into the skin through the through hole 3h of the hollow protrusion 3, the inner diameter of the through hole 3h on the inner surface 31 side is preferably 1 μm or more, more preferably 5 μm or more, and preferably is 500 μm or less, more preferably 300 μm or less, specifically, preferably 1 μm or more and 500 μm or less, and even more preferably 5 μm or more and 300 μm or less.

From the viewpoint of stably supplying the agent into the skin through the through hole 3h of the hollow protrusion 3, the inner diameter of the through hole 3h on the outer surface 32 side is preferably 1.1 times or more as compared to the inner diameter on the inner surface 31 side. More preferably 1.2 times or more, and preferably 15 times or less, still more preferably 10 times or less, specifically, preferably 1.1 times or more and 15 times or less, and still more preferably is 1.2 times or more and 10 times or less. From the viewpoint of more stably supplying the agent into the skin through the through hole 3h of the hollow protrusion 3, 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. Preferably, it is increasing. In other words, by irradiating the hollow protrusion 3 with the laser beam 4L from the outside of the hollow protrusion 3, an opening is formed on the outside of the hollow protrusion with respect to the diameter of the aperture formed on the inside of the hollow protrusion. A through hole 3h with a large hole diameter is formed. The shape of the through hole 3h is formed into a truncated conical shape.

Next, a method for manufacturing a hollow protrusion according to the present invention will be described with reference to FIGS. 4 and 5, taking the method for manufacturing the hollow protrusion 1 described above as an example. FIG. 4 shows the overall configuration of a manufacturing apparatus 100 according to an embodiment used to carry out the method for manufacturing the hollow protrusion 1. As shown in FIG. As mentioned above, each hollow protrusion 3 of the hollow protrusion 1 is very small, but for convenience of explanation, each hollow protrusion 3 of the hollow protrusion 1 is exaggerated in FIG. 4. .

As shown in FIG. 4, the manufacturing apparatus 100 includes a protrusion forming part 10 that includes a convex part 11 for forming a hollow protrusion 3 on a base sheet 2A, and a through hole 3h in the hollow protrusion 3. The aperture forming section 40 has a non-contact aperture means. In this embodiment, the manufacturing apparatus 100 includes a cooling section 20. The manufacturing apparatus 100 inserts the convex portion 11 from one surface 2D side of the base sheet 2A to form a non-penetrating hollow protrusion 3 protruding from the other surface 2U side of the base sheet 2A, and then A through hole 3h is formed in the non-penetrating hollow protrusion 3 from the other surface 2U side of the material sheet 2A by a hole-opening means. The base portion 2 indicates a portion of the hollow protrusion 1 formed from the base sheet 2A where the hollow protrusion 3 is not formed.

A method for manufacturing the hollow protrusion 1 using the manufacturing apparatus 100 will be described in detail. In the following description, the direction in which the base sheet 2A is conveyed is the Y direction, the direction orthogonal to the conveying direction and the second direction of the base sheet 2A being conveyed is the X direction, and the thickness direction of the base sheet 2A being conveyed. will be explained assuming that it is the Z direction.
In the method for manufacturing the hollow protrusion 1 using the manufacturing apparatus 100, first, as shown in FIG. 4, the band-shaped base sheet 2A is unwound from the raw material roll of the base sheet 2A and conveyed in the conveyance direction Y. Then, when the base sheet 2A is sent to a predetermined position, the conveyance of the base sheet 2A is stopped. In this way, in the method for manufacturing the hollow protrusion 1, the belt-shaped base sheet 2A is conveyed intermittently.

The base sheet 2A is a sheet that serves as a base material of the hollow protrusion 1 to be manufactured, and contains a thermoplastic resin. The base sheet 2A preferably contains thermoplastic resin as a main component, that is, contains 50% by mass or more of thermoplastic resin, and more preferably contains 90% by mass or more of thermoplastic resin. Examples of thermoplastic resins include polyolefin resins such as polyethylene, polypropylene, ethylene-α-olefin copolymer, and ethylene-propylene copolymer; polyethylene terephthalate, polybutylene terephthalate, liquid crystal polymer, polyhydroxyalkanoate, polycaprolactone, polybutylene succinate, and polyethylene terephthalate. Polyester resins such as polylactic acid resins such as glycolic acid, polylactic acid and lactic acid-hydroxycarboxylic acid copolymers; polyamide resins such as nylon 6 and nylon 66; polyvinyl chloride, polyvinylidene chloride, polyvinyl acetate, polyvinyl acetate-ethylene Vinyl polymers such as copolymers and polystyrene; acrylic polymers such as polyacrylic acid, polyacrylic ester, polymethacrylic acid and polymethacrylic ester; polycarbonate; polyamideimide; polyetherketone, polyetheretherketone, polyether Examples include aromatic polyetherketone resins such as etherketoneketone; polyetherimide; and modified cellulose obtained by chemically modifying cellulose molecules. The base sheet 2A may be made of a mixture containing hyaluronic acid, collagen, starch, cellulose, etc. in addition to the thermoplastic resin. The thickness of the base sheet 2A is equivalent to the thickness T2 of the base portion 2 of the hollow protrusion 1 (see FIG. 3). That is, the hollow protrusion 3 is preferably formed of a material containing thermoplastic resin.

Next, in the manufacturing method of the hollow protrusion 1, as shown in FIG. A protrusion forming step is performed to form minute hollow protrusions 3 protruding from the other surface 2U side.

As shown in FIG. 4, the protrusion forming section 10 includes a convex portion 11 for forming a protrusion. Although the convex portion 11 may or may not be provided with a heating means (not shown), the manufacturing apparatus 100 is provided with a heating means (not shown). Further, in the manufacturing apparatus 100, there is no need to provide any heating means other than the heating means for the convex portion 11. In this specification, "no heating means other than the heating means for the convex portion 11" refers not only to the case where no other heating means is provided, but also to the case where the softening temperature of the base sheet 2A is lower than the The meaning also includes cases where a means for heating below the glass transition temperature is provided. However, it is preferable that no other heating means be included.

The convex portion 11 is a member having a convex shape 110 that is a part that sticks into the base sheet 2A. It has a structure. However, the present invention is not limited thereto, and may be a convex portion consisting of only convex molds 110, or may be a convex portion 11 in which a plurality of convex molds 110 are disposed on a platform support. The convex part 11 has a convex part 110 corresponding to the number, arrangement, and approximate external shape of each hollow protrusion 3 of the hollow protrusion 1 to be manufactured. It has nine conical convex molds 110 corresponding to the conical hollow protrusions 3 .

The convex mold 110 is formed into a conical shape with nine sharp tips, as shown by the broken line in FIG. 4, and is arranged with the tips facing upward in the thickness direction Z. The convex portions 11 are disposed on one surface 2D side (lower surface side) of the base sheet 2A at a constant interval below the one surface 2D in the thickness direction Z. The convex portion 11 is movable up and down in the thickness direction Z by an electric actuator (not shown). The convex mold 110 is configured such that the tip of the convex mold 110 of the convex part 11 can be brought into contact with the base sheet 2A from one surface 2D side.

In this embodiment, the heating means for the convex portion 11 is an ultrasonic vibration device. It is preferable that the ultrasonic vibration of the convex portion 11 is performed from immediately before the convex portion 11 comes into contact with the base sheet 2A to immediately before the next step, the cooling step, which will be described later. The operation of the convex part 11 and the heating conditions of the heating means of the convex part 11, such as the operation of the heating means of the convex part 11, are controlled by a control means (not shown) provided in the manufacturing apparatus 100.

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

As shown in FIG. 4, the protrusion forming part 10 has a first opening plate 12U as a deflection suppressing means on the other surface 2U side (upper surface side) of the base sheet 2A, and has a first opening plate 12U as a deflection suppressing means on the one surface 2D side of the base sheet 2A. It has a second opening plate 12D (on the lower surface side) as a deflection suppressing means. The first and second aperture plates 12U and 12D are formed from plate-like members extending parallel to the transport direction Y. The first and second aperture plates 12U and 12D sandwich the base sheet 2A in areas other than the aperture 12a.

The first and second aperture plates 12U, 12D have 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 part 11 can be inserted into one opening 12a. However, in this embodiment, as shown in FIGS. 4 and 5, one convex mold 110 is formed to be inserted into one opening 12a. In the manufacturing apparatus 100, the opening 12a of the first opening plate 12U is arranged concentrically with the opening 12a of the second opening plate 12D. Therefore, the openings 12a of the pair of first aperture plates 12U and the apertures 12a of the second aperture plates 12D that sandwich the base sheet 2A overlap in the thickness direction.

The first and second aperture plates 12U and 12D are movable in a direction in which they come into contact with the base sheet 2A and in a direction in which they separate from each other. In the manufacturing apparatus 100, the first and second aperture plates 12U and 12D are movable up and down in the thickness direction Z by an electric actuator (not shown). The operation of the first and second aperture plates 12U and 12D is controlled by a control means (not shown) provided in the manufacturing apparatus 100.
In addition, in this embodiment, the first aperture plate 12U and the second aperture plate 12D are movable in a direction in which they come into contact with the base sheet 2A and in a direction in which they separate from each other. Of these, the second aperture plate 12D does not need to be movable in the direction in which it comes into contact with the base sheet 2A and in the direction in which it separates from the base sheet 2A.

In the method for manufacturing the hollow protrusion 1, as shown in FIGS. 5(a) and 5(b), the protrusion is formed with the base sheet 2A sandwiched between the first aperture plate 12U and the second aperture plate 12D. A forming process is performed. In the protrusion forming step, the convex mold 110 is passed through the opening 12a of the second aperture plate 12D from the one surface 2D side of the base sheet 2A, and each convex is formed using an ultrasonic vibrator as shown in FIG. 5(a). While causing the mold 110 to generate ultrasonic vibrations in advance, the convex mold portion 11 is then brought into contact with one surface 2D of the base sheet 2A. 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 surface 2D side of the base sheet 2A toward the other surface 2U side, and the base sheet 2A is The convex mold 110 is inserted into the base sheet 2A while suppressing the deflection of the base sheet 2A with the first opening plate 12U disposed on the other surface 2U side. Then, minute non-penetrating hollow protrusions 3 are formed that protrude from the other surface 2U side of the base sheet 2A.

From the viewpoint of forming the hollow projections 3, the heating temperature of the base sheet 2A by heating the convex portions 11 is preferably higher than or equal to the glass transition temperature of the base sheet 2A to be used and lower than the melting temperature, particularly the softening temperature. It is preferable that the melting temperature is higher than that or lower than the melting temperature. In addition, when heating the base sheet 2A using an ultrasonic vibration device, the temperature range is applied as the temperature range of the portion of the base sheet 2A that is in contact with the convex mold 110. On the other hand, when heating the base sheet 2A using a heating device instead of the ultrasonic vibration device, the heating temperature of the convex portion 11 may be adjusted within the above-mentioned range. Note that the glass transition temperature (Tg) may be measured in accordance with JIS K-7196 "Softening temperature test method by thermomechanical analysis of thermoplastic plastic films and sheets" as a known method for measuring the softening temperature.

Next, in the method for manufacturing the hollow protrusion 1, as shown in FIGS. 4 and 5(c), a cooling step is performed in which the hollow protrusion 3 is cooled using the cold air blower 21 included in the cooling unit 20. As shown in FIG. 4, the cold air blowing device 21 has an air outlet 22 for blowing cold air arranged on the other surface 2U side (upper surface side) of the base sheet 2A, and blows cold air from the air outlet 22 to clean non-penetrating areas. The hollow protrusion 3 is cooled. The cold air blower covers the entire other surface 2U side (upper surface side) and one surface 2D side (lower surface side) of the belt-shaped base sheet 2A to be conveyed in a hollow shape, and the inside of the cold air blower is covered with the belt-shaped base sheet. 2A may be conveyed in the conveyance direction (Y direction), and an 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.

In the method for manufacturing the hollow protrusion 1, a cooling process is performed in which the non-penetrating hollow protrusion 3 is cooled while the convex portion 11 is inserted into the non-penetrating hollow protrusion 3. In the cooling process, the movement of the convex part 11 in the thickness direction (Z direction) by an electric actuator (not shown) was stopped, and the convex mold 110 of the convex part 11 was inserted into the non-penetrating hollow protrusion 3. In this state, cool 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 convex mold 110 inserted inside the non-penetrating hollow protrusion 3. do.

When the heating means for the convex part 11 is ultrasonic vibration, as in the manufacturing apparatus 100, it is not necessary to necessarily provide the cold air blower 21, and cooling may be performed by cutting off the vibration of the ultrasonic vibration apparatus. can. In this respect, it is preferable to use ultrasonic vibration as the heating means because it not only simplifies the apparatus but also facilitates the manufacture of the hollow protrusion 1 at high speed. In addition, heat is less likely to be transferred to the portions of the base sheet 2A that are not in contact with the convex portions 11, and since cooling is performed efficiently by turning off the application of ultrasonic vibration, deformation occurs in areas other than the molded portions. It has the advantage of being difficult.

In the manufacturing method of the hollow protrusion 1, the through hole 3h is formed at the planned opening position of the hollow protrusion 3 while cooling the non-penetrating hollow protrusion 3 in the cooling process or after the cooling process is finished. However, in the manufacturing method shown in FIGS. 4 and 5, while cooling the non-penetrating hollow protrusion 3, a non-contact hole opening means provided in the hole forming section 40 is used. A laser is irradiated to the intended opening position of the non-penetrating hollow protrusion 3 to form a through hole 3h, which is a through hole, in the non-penetrating hollow protrusion 3. If the through holes 3h are formed in the hollow protrusion 3 while cooling the non-penetrating hollow protrusion 3 in this manner, the cooling process and the hole forming process can be performed simultaneously, making it possible to shorten the manufacturing time. In this embodiment, the planned hole opening position is a portion of the hollow protrusion 3 where the through hole 3h is formed by irradiation with the laser.

The hole forming section 40 includes a non-contact hole forming means on the other surface 2U side of the base sheet 2A. A laser irradiation device 4 is used as a non-contact hole opening means. As shown in FIG. 4, the laser irradiation device 4 includes an irradiation head 41 that is a galvano scanner that freely scans a laser beam 4L. The irradiation head 41 is arranged on the other surface 2U side (upper surface side) of the base sheet 2A at a constant interval above the other surface 2U in the thickness direction Z.
In this way, the laser beam 4L is irradiated from the irradiation head 41 arranged on the other surface 2U side (upper surface side) of the base sheet 2A to the planned hole opening position of the non-penetrating hollow protrusion 3 to penetrate into the hollow protrusion 3. When the hole 3h is formed, burrs are less likely to be formed around the through hole 3h on the outer surface 32 of the hollow protrusion 3. Furthermore, since the through hole 3h can be easily formed at any arbitrary position of the hollow protrusion 3, it is easy to arbitrarily control the position relative to the skin surface to which the liquid agent or the like is to be supplied.

As shown in FIG. 4, the irradiation head 41 includes a lens 43 for condensing the irradiated laser beam 4L, two mirrors 42 for freely scanning the condensed laser beam 4L, and a protective lens 44. The protective lens 44 may or may not be provided, but it is preferable to provide it in order to prevent dirt and dust from entering the optical system. Mirror 42 is attached to the motor shaft. The mirror 42 is 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 moves in the direction X perpendicular to the conveying direction of the base sheet 2A. The laser beam 4L can be scanned freely. The lens 43 is movable in the optical axis direction, and has a mechanism that focuses the laser beam 4L and makes the spot diameter of the irradiation point of the laser beam 4L constant, which hits the hollow protrusion 3, based on the irradiation point of the laser beam 4L. It is equipped with a mechanism for moving the material sheet 2A in the thickness direction Z direction. The irradiation head 41, which includes a mirror 42 and a lens 43, is capable of adjusting the irradiation point of the laser beam 4L three-dimensionally in the X direction, Y direction, and Z direction. Therefore, by three-dimensionally coordinating the desired irradiation position (proximity) of each of the nine hollow protrusions 3, the laser beam 4L can be irradiated to the desired irradiation position of each hollow protrusion 3 with a predetermined spot diameter. I can do it.

In the manufacturing method of the hollow protrusion 1, as shown in FIG. The non-penetrating hollow protrusion 3 is irradiated with a laser beam 4L from the irradiation head 41 to form a through hole 3h. When the through hole 3h is formed by irradiating the laser beam 4L with the convex portion 11 inserted inside the non-penetrating hollow protrusion 3 in this way, the area around the through hole 3h on the inner surface 31 of the hollow protrusion 3 is formed. Burrs are less likely to form and the agent can be stably supplied to the inside of the skin. Furthermore, when the through hole 3h is formed by irradiating the laser beam 4L with the convex portion 11 inserted into the non-penetrating hollow protrusion 3, the side wall of the hollow protrusion 3 on the side irradiated with the laser beam 4L The inner surface 31 of the opposite side wall is less likely to be damaged, and the agent can be stably supplied to the inside of the skin.

In the manufacturing method of the hollow protrusion 1, as shown in FIG. is formed, and cooling of the hollow protrusion 3 is stopped. Next, as shown in FIG. 5E, a release step is performed in which the convex portion 11 is removed from the inside of the hollow protrusion 3 in which the through hole 3h is formed to form the hollow protrusion 3 having a hollow interior. If the ultrasonic vibration of the convex portion 11 by the ultrasonic vibrator is continued in the cooling process, it is preferable to stop the ultrasonic vibration in the release process. In the release process, the convex part 11 is moved downward in the thickness direction (Z direction) by an electric actuator (not shown), and from the state where the convex part 110 is inserted into the inside of each hollow protrusion part 3, the convex part 110 is moved downward in the thickness direction (Z direction). is removed to form a hollow protrusion 3 having a hollow interior. In the release process, since the second opening plate 12D is used as a deflection suppressing means for suppressing the deflection of the base sheet 2A when the convex part 11 is extracted from the inside of the hollow protrusion 3, the convex part 110 is removed from the hollow protrusion part. It is easy to remove from the inside of 3.

In the method for manufacturing the hollow protrusion 1, it is possible to manufacture a precursor 1A of the hollow protrusion 1 in which nine hollow protrusions 3 are arranged on the other surface 2U (upper surface) of the base sheet 2A. After the precursor 1A of the hollow protrusion 1 is manufactured, the first aperture plate 12U and the second aperture plate 12D are separated from the base sheet 2A to release the base sheet 2A from the sandwiched state.

The precursor 1A of the hollow protrusion 1 formed as described above is then transported downstream in the transport direction Y. Thereafter, in a cutting process, a predetermined range is cut, and a hollow protrusion 1 having a sheet-like base portion 2 and a plurality of hollow protrusions 3 as shown in FIG. 1 can be manufactured. By repeating the above steps, the hollow protrusion 1 can be manufactured continuously and efficiently.
The hollow protrusion 1 manufactured as described above may be further formed into a predetermined shape in a subsequent step, or the base sheet 2A may be formed into a desired shape in advance before the step of inserting the convex portion 11. You can adjust it.

Next, the process of forming the through holes 3h using the laser irradiation device 4 will be described in detail.
In the techniques described in Patent Documents 1 to 3 mentioned above, one hollow protrusion among a plurality of hollow protrusions is irradiated with a laser beam 4L whose output is adjusted to be able to form a through hole with one irradiation. There is. As a result, a through hole 3h that penetrates from the outer surface 32 to the inner surface 31 is formed in a part of the side wall where the hollow protrusion 3 is to be opened, by being melted by the thermal energy of the laser beam 4L irradiated at once. . Further, the irradiation position of the laser beam 4L is also one for one hollow protrusion. For this reason, the energy of the irradiated laser beam 4L is concentrated in one place, resulting in a large local temperature rise, and as the temperature rises, a lot of heat is transferred to the surroundings of the irradiation range, resulting in the effects of heat on the periphery of the irradiation range. tends to increase. The effects of heat include thinning and thermal degeneration around the through hole of the hollow protrusion 3 due to unexpected melting. As described above, when forming the through hole 3h in the fine hollow protrusion 3 by laser irradiation (laser processing), there is a concern that the strength may be insufficient.

In other words, the part of the side wall that is opened by irradiation with the laser beam 4L may be melted because the hole is made, but if the part that is not opened softens or melts as the temperature rises, the thickness of the hollow protrusion becomes thinner. It may also become brittle due to thermal denaturation. If a hollow protrusion with a through hole 3h formed by one irradiation is punctured into the skin, the hollow protrusion may be damaged due to lack of strength due to weakening, and it is difficult to maintain the strength of the hollow protrusion. In this respect, issues remain. In addition, in the techniques of Patent Documents 1 to 3, the number of irradiations of the laser beam 4L is devised when forming a through hole to suppress weakening of the hollow protrusion due to irradiation, and at the same time, the through hole is formed by thermal processing. No description of thoughts can be found.

Therefore, when forming the through hole 3h in the fine hollow protrusion 3, the inventor focused on the method of irradiating the laser beam 4L. In the formation step (processing step) of forming the through hole 3h, the laser beam 4L is irradiated onto the outer surface 32 of the side wall of the hollow protrusion 3 to gradually deepen its depth and finally reach the inner surface 31. The method of forming the penetrating through hole 3h, and the method of forming the through hole 3h with a smaller diameter than the through hole 3h and penetrating the hollow protrusion 3 from the outer surface 32 to the inner surface 31 with a smaller diameter than the through hole 3h. By connecting and integrating them, we have reached a method of forming 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.

[First embodiment]
FIGS. 6(a) to 6(d) show the process of forming a through hole according to the first embodiment. In the first embodiment, the hollow protrusion 3 is irradiated with a laser beam 4L from the laser irradiation device 4 multiple times with an output that does not penetrate the side wall, which is the planned opening position of the hollow protrusion 3, in one irradiation. By doing so, a through hole 3h is formed.
In this case, the spot diameter of the laser beam 4L emitted from the laser irradiation device 4 is made somewhat smaller on the outer surface 32 than the designed opening diameter of the through hole 3h. This is because the hollow protrusion 3 is melted somewhat wider than the spot diameter due to the heat generated by the irradiation of the laser beam 4L. When irradiating multiple times, the spot diameter may be the same, or the spot diameter may be initially smaller than the designed opening diameter of the through hole 3h, and finally the spot diameter may be smaller than the designed diameter of the through hole 3h. Irradiation may be performed by changing the spot diameter so that it gradually [stepwise] increases to a spot diameter corresponding to the opening diameter of the through hole.

The number of times the laser beam 4L is irradiated until the through-hole 3h is formed is preferably determined experimentally depending on 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 recommended 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 irradiating it 2 to 5 times, for example. is preferred. The through holes 3h may be formed by irradiating the laser beam 4L 10 times or more, but the greater the number of irradiations, the more the microneedle array which is the hollow protrusion 1 having the hollow protrusions 3 in which the through holes 3h are formed. It takes time to manufacture one product, which is unfavorable in terms of productivity. For this reason, it is preferable to limit the number of irradiations to 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.

When irradiating the laser beam 4L multiple times to form the through hole 3h, it is better to use the same irradiation position to melt the same spot each time, effectively increasing the depth of the hole and making the hole penetrate. This is preferable because the time required for (opening) can be shortened.
Regarding the output of the laser beam 4L that forms the through hole 3h, it is recommended to set the output to such an extent that the material at the planned hole opening position (side wall) forming the through hole 3h will not penetrate but will be melted by one laser irradiation. preferable. For example, when it is assumed that the through hole 3h is formed by irradiating the laser beam 4L three times, the first laser beam irradiation shown in FIG. 6(b) starts immediately after the formation of the hollow projection 3 shown in FIG. 6(a). About 1/3 of the thickness of the side wall of the hollow protrusion 3 is melted by irradiation, and about 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). However, as shown in FIG. 6(d), a through hole 3h penetrating from the outer surface 32 to the inner surface 31 can be formed by the third laser irradiation (see FIG. 3).
7(a) shows one of the hollow protrusions 3 in which the through hole 3h is formed, viewed from the irradiation side, and FIG. 7(b) shows the through hole 3h formed in the hollow protrusion 3 and , is an enlarged view showing the affected area of the surrounding area 3g.

In this way, by irradiating the outer surface 32 of the side wall of the hollow protrusion 3 to be irradiated with the laser beam 4L multiple times at an output that does not open the through hole 3h in one irradiation, the laser beam 4L can be irradiated from the outer surface 32 of the side wall to the inner surface 31. The side wall is melted in stages to form a through hole 3h. Therefore, the amount of heat applied to the hollow protrusion 3 per one 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 degeneration due to the influence of heat or unexpected thinning, in the peripheral portion 3g where the through hole 3h is formed by irradiation with the laser beam 4L. In other words, since the thermal effect caused by the irradiation of the laser beam 4L when forming the through hole in the hollow protrusion 3 is reduced, it is possible to suppress the peripheral part 3g of the through hole 3h from becoming brittle, and the hollow protrusion 1 can be formed while maintaining its strength. It is possible to provide.
In the embodiment, the opening diameter r1 of the through hole 3h refers to the opening diameter r1 of the through hole 3h, as shown in FIG. This is the width of the hole 3h. Further, the radius r2 of the surrounding area (heat affected area) 3g, which is the area affected by heat, is the width of the surrounding area 3g, which is the area affected by heat, in the width direction (X direction). By irradiating the laser beam 4L multiple times as in this embodiment, the diameter r2 of the peripheral portion 3g can be made smaller than in the conventional configuration.
In addition, when measuring the width of the peripheral portion 3g formed around the through hole 3h by laser irradiation and affected by heat, the width of the through hole 3h is The discolored part around the hole 3h, or the inclined side surface when the shape of the through hole 3h is considered to be a truncated cone, is defined as the part thinned due to the influence of heat, and the area around the bottom of the truncated cone The value of the diameter r2 of the peripheral part 3g can be determined by measuring the width of the peripheral part 3g using a microscope or a scanning electron microscope (SEM), with 3g being the peripheral part 3g affected by heat.

[Second embodiment]
FIGS. 8(a) to 8(d) show the process of forming the through hole 3h according to the second embodiment. In the second embodiment, the laser beam 4L having an output that penetrates the hollow protrusion 3 with an opening diameter smaller than the opening diameter r1 of the through hole 3h in one irradiation is applied to the same surface of the hollow protrusion 3. By irradiating the outer surface 32 multiple times, the through holes 3h are formed.
In this case, the spot diameter of the laser beam 4L irradiated from the laser irradiation device 4 is smaller than the designed opening diameter of the through hole 3h on the outer surface 32 of the hollow protrusion 3, and the output of the laser beam 4L is one time. The output is set so that the irradiation penetrates from the outer surface 32 to the inner surface 31 (through the side wall). Further, in this embodiment, the spot diameter of the laser beam 4L increases each time the laser beam 4L is irradiated. When the spot diameter is increased, if the laser output remains the same as before changing the spot diameter, it is assumed that the amount of irradiation energy per unit area will decrease and the laser will not penetrate the hollow protrusion 3. For this reason, in this embodiment, the laser output is increased as the spot diameter increases to ensure that penetration is possible with an opening diameter smaller than the designed diameter in one irradiation.

For example, when it is assumed that the through hole 3h is formed by irradiating the laser beam 4L three times, the first laser beam irradiation shown in FIG. 8(b) starts immediately after the formation of the hollow protrusion 3 shown in FIG. By irradiation, an opening 301 is formed in the side wall of the hollow protrusion 3 with a diameter smaller than that of the through hole 3h, and in the second laser irradiation as shown in FIG. The output laser beam 4L is irradiated onto the aperture 301 to form an aperture 302 that has a larger diameter than the aperture 301 and penetrates through it. As shown in FIG. 8(d), in the third laser irradiation, the laser beam 4L, which is larger than the second spot diameter and has a high power, is irradiated onto the aperture 302 and penetrates with a diameter larger than the aperture 302. An opening 303 is formed. In this embodiment, this opening 303 becomes the through hole 3h shown in FIG. 9(a).

As in the second embodiment, when the through hole 3h is formed by irradiating the laser beam 4L multiple times to form an opening with a diameter smaller than the designed dimension of the through hole 3h, the hollow protrusion 3 The through holes 3h may be formed by irradiating multiple times on mutually adjacent portions on the same surface. In this case, the laser beam output and spot diameter are the same for each irradiation, and only the irradiation position is changed.
For example, when forming the through hole 3h by irradiating the laser beam 4L three times, as shown in FIG. 9(b), the locus of the apex of a triangle (equilateral triangle is shown in FIG. 9(b)) on the outer surface 32. Irradiate the laser beam 4L three times as if drawing In this case, 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 mutually exclusive. The irradiation position is adjusted so that it is formed adjacent to. The symbol P in the figure indicates the center-to-center distance of the spot diameter P1.

When the laser beams 4L, which penetrate the hollow protrusion 3 in one irradiation and whose diameter is smaller than the through hole 3h, are irradiated to mutually adjacent parts of the same surface of the outer surface 32, the irradiation of each laser beam 4L causes The formed openings 301 to 303 are melted and connected by heat. Therefore, as shown by the broken line in FIG. 9(b), the through hole 3h, which is larger than the spot diameter P1 of the laser beam 4L, can be formed with less thermal influence, and the surrounding portion 3g of the through hole 3h can be prevented from becoming brittle. , it is possible to provide a hollow protrusion 1 that maintains strength.

When the through-hole 3h is formed by irradiating the laser beam 4L multiple times, which penetrates the hollow protrusion 3 with one irradiation but has a smaller diameter than the through-hole 3h, an opening is formed as shown in FIG. 9(c). By irradiating the laser beam 4L so that at least two of the hole 301, the opening 302, and the opening 303 overlap with each other, they may be connected and integrated to form one through hole 3h. . Even in this case, the through hole 3h, which is larger than the spot diameter P1 of the laser beam 4L, can be formed with less thermal influence, and the same effect as described above can be achieved.

In the first and second embodiments, one through hole 3h was formed for one hollow protrusion 3, but the number of through holes 3h is as shown in FIGS. 10(a) and 10(b). A plurality of through holes 3h may be formed in one hollow protrusion 3.
10(a) shows a form in which two through holes 3h are formed side by side in the protrusion direction (thickness direction Z) of the hollow projection 3, and FIG. This figure shows a configuration in which a plurality of sheets are formed so as to be line symmetrical with respect to a center line CL passing through the center of the tip. In FIG. 10(b), through holes 3h are formed in the outer surface 32, which is a portion located in the width direction (X direction) of the hollow protrusion 3. As shown in FIG.
When forming a plurality of through holes 3h in the protrusion direction (thickness direction Z) as shown in FIG. direction Z). As shown in FIG. 10(b), when forming one through hole 3h in each width direction (X direction), once the through hole 3h is formed on one side of all the hollow protrusions 3, The direction of the protrusion 1 may be rotated by 180 degrees, and the through hole 3h may be formed on the other side using the laser irradiation device 4.
By forming a plurality of through holes 3h in this manner, the supply rate of the agent accommodated in the space 3k of the hollow protrusion 3 can be adjusted. Furthermore, when a plurality of through holes 3h are formed in the thickness direction Z, the agent can be supplied to different skin layers when the microarray (hollow protrusions 1) is punctured into the skin.

It is preferable to use a laser beam 4L that can be absorbed by the hollow protrusion 3 as the laser beam 4L that forms the through hole 3h. When the base sheet 2A forming the hollow protrusion 3 is a sheet such as a film mainly made of thermoplastic resin, the laser beam 4L may include a CO ₂ laser, excimer laser, argon laser, YAG laser, LD laser (semiconductor laser), etc. It is preferable to use a UV laser, such as a laser), a YVO ₄ laser, or a fiber laser.
That is, from the viewpoint of being able to reduce thermal effects, and from the viewpoint of laser equipment installation, handling, 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.

From the same 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, and preferably 1 fs or more and 10 ms or less. It is more preferably 100 fs or more and 5 ms or less, and still more preferably 1000 fs or more and 1 ms or less.

The through hole 3h may be formed at the tip of the hollow protrusion 3, but from the viewpoint of maintaining the strength and sharp shape of the tip of the hollow protrusion 3 to make it easier to puncture the skin, the step of forming the through hole 3h is Then, it is preferable that 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, so that the tip of the hollow protrusion 3 is not affected by the laser irradiation. . The perspective of forming the through hole 3h by irradiating the inclined side wall of the hollow protrusion 3 with the laser beam 4L with less irradiation energy, and the aspect of forming the through hole 3h by reducing the area irradiated with the laser beam 4L and suppressing the influence of irradiation energy. From the viewpoint of maintaining the strength around the hole 3h and from the viewpoint of reducing the influence of laser irradiation on the adjacent hollow protrusion, in the through-hole formation process, as shown in FIG. 5(c), a laser irradiation device 4 is used. It is preferable to form the through hole 3h by irradiating the non-penetrating hollow protrusion 3 with a laser beam 4L from the irradiation head 41 in a direction ILf inclined with respect to the insertion direction ILe of the convex mold 110 of the convex part 11.

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, It is particularly preferably 15 degrees or more, more preferably 85 degrees or less, even more preferably 80 degrees or less, and particularly preferably 75 degrees or less. Specifically, the angle 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.

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, and more preferably 0.5 ms or more. , and is preferably 100 ms or less, more preferably 70 ms or less, specifically, preferably 0.1 ms or more and 100 ms or less, and even more preferably 0.5 ms or more and 70 ms or less.

Further, from the same viewpoint, the laser output of the laser beam 4L is preferably 0.5W or more, more preferably 1W or more, and preferably 100W or less, and even more preferably 50W or less. Preferably, specifically, it is preferably 0.5W or more and 100W or less, and more preferably 1W or more and 50W or less.

The thickness of the hollow protrusion 3 at the planned hole opening position is at least 0.01 mm or more, preferably 0.02 mm or more, and 0.7 mm or less, preferably 0.5 mm or less, to improve the thermoplasticity of the base sheet 2A. It is desirable to irradiate the resin multiple times because it is possible to more significantly reduce the thermal effect and to obtain the strength to puncture the skin with the hollow protrusion 3.

The ultraviolet transmittance when the base sheet 2A forming the hollow projections 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 It is preferably 90% or less, specifically, 60% or more and 95% or less, more preferably 65% or more and 90% or less, and still more preferably 70% or more and 90% or less. That is, the hollow protrusion 3 is preferably formed of a material having an ultraviolet transmittance of 60% or more and 95% or less. When the ultraviolet transmittance is within this range, thermal effects caused by excessive transmission of laser energy to the hollow protrusion 3 can be suppressed, and processing can be performed with high precision.

In the embodiment described above, the convex portion 11 for forming a protrusion is inserted from one side of the sheet-like base portion 2 which is a base material formed of a thermoplastic resin, and the other portions of the base portion 2 are inserted. After the protrusion processing step of forming the non-penetrating hollow protrusion 3 protruding from the surface side, the hollow protrusion 3 is irradiated with the laser beam 4L multiple times to form the through hole 3h, thereby forming the protrusion. After the processing step, the hollow protrusion 1 having a continuous through hole 3h can be formed.
Furthermore, strength can be maintained by manufacturing the hollow protrusion 1 equipped with the fine hollow protrusion 3 having the through hole 3h using the above-described manufacturing method.

As explained above, according to the manufacturing method of this embodiment using the manufacturing apparatus 100 for manufacturing the hollow protrusion 1, the convex portion 11 is inserted from the one surface 2D side of the base sheet 2A to A minute non-penetrating hollow protrusion 3 protruding from the other surface 2U side of 2A is formed in the protrusion forming step, and the non-perforated hollow protrusion 3 is irradiated with a laser beam 4L from a laser irradiation device 4 multiple times. By doing so, since the formation step of forming the through hole 3h is provided, the magnitude of the thermal influence can be suppressed to a minimum, and the hollow protrusion 1 with ensured strength can be manufactured.

Although the present invention has been described above based on the preferred embodiment, the present invention is not limited to the embodiment and can be modified as appropriate.
For example, in the method for manufacturing the hollow protrusion 1 described above, with the convex part 11 inserted into the non-penetrating hollow protrusion 3, the laser irradiation device 4 is cooled while the hollow protrusion 3 is cooled in the cooling process. A through hole 3h penetrating the hollow protrusion 3 is formed using a laser irradiation device 4 after removing the convex part 11 from the inside of the non-penetrating hollow protrusion 3. A through hole 3h penetrating through the protrusion 3 may be formed. Specifically, as shown in FIGS. 11(a) and 11(b), with the base sheet 2A sandwiched between the first aperture plate 12U and the second aperture plate 12D, the base sheet 2A is The convex molds 110 are passed through the openings 12a of the second aperture plate 12D from the surface 2D side, and the convex parts 11 are moved to the base sheet 2A while causing each convex mold 110 to generate ultrasonic vibration in advance using an ultrasonic vibration device. Abut against one side 2D of. As a result, while softening the contact portion TP, the convex mold 110 is raised from the one surface 2D side of the base sheet 2A toward the other surface 2U side, and the non-penetrating part protruding from the other surface 2U side of the base sheet 2A is raised. A hollow protrusion 3 is formed.

Next, as shown in FIG. 11(c), the non-penetrating hollow projections 3 are 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 step is performed in which the convex portion 11 is removed from the inside of the non-penetrating hollow protrusion 3 to form the hollow protrusion 3 having a hollow interior. In the release process, the ultrasonic vibration of the convex part 11 by the ultrasonic vibrator is stopped, and the convex part 11 is moved downward in the thickness direction (Z direction) by an electric actuator (not shown), and the second opening plate is moved downward in the thickness direction (Z direction). 12D to suppress the deflection of the base sheet 2A, the convex mold 110 is removed from the inside of the hollow protrusion 3 to form a non-penetrating hollow protrusion 3.

Next, as shown in FIG. 11(d), after cooling, a hollow protrusion that does not allow the laser beam 4L to pass through from the irradiation head 41 of the laser irradiation device 4 disposed on the other surface 2U side (upper surface side) of the base sheet 2A. 3 to form a through hole 3h, and as shown in FIG. 11(e), a hollow protrusion 3 having a through hole 3h formed therein may be formed.
In the method for manufacturing the hollow protrusion 1 described above, 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 Hereinafter, the present invention will be explained in more detail with reference to examples, but the scope of the present invention is not limited to these examples.

1. Preparation of laser device included in manufacturing equipment As the laser irradiation device 4 for forming the through hole 3h, one uses a CO ₂ laser device to irradiate a CO ₂ laser beam 4L with a wavelength of 9.3 μm, and the other uses a UV laser device. A device for irradiating 4L of UV laser beams with a wavelength of 355 nm was prepared.
2. Preparation of Base Sheet 2A As the base sheet 2A, a belt-shaped sheet of polylactic acid (PLA; Tg 55.8° C.) with a thickness of 0.4 mm was prepared.
3. Formation of non-penetrating hollow protrusions The non-penetrating hollow protrusions 3 were formed in the order shown in FIGS. 6(a) to 6(c). As a forming condition, the amplitude of the ultrasonic vibration of the convex portion 11 is 70%. The insertion height of the convex portion 11 was 1.4 mm, and the insertion speed was 2 mm/sec. Further, the softening time was 0.3 seconds, and the cooling time was 1.0 seconds. The protrusion height H1 of the formed hollow protrusion 3 was 1 mm (1000 μm).

[Example 1]
Table 1 shows the measurement conditions and measurement results of 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. Specifically, the position from the tip of the hollow protrusion 3 is 600 μm, the laser output of the laser beam 4L from the CO ₂ laser device is 3.2 W, and the angle θ between the insertion direction ILe and the inclined direction ILf is 30 degrees. The hollow protrusion 3 was irradiated with the laser beam 4L nine times to form a through hole 3h having an opening diameter (through hole diameter) r1 of 40 μm. At this time, the diameter (heat-affected diameter) r2 of the heat-affected peripheral portion 3g formed around the through-hole 3h by laser irradiation is 120 μm, and the ratio of heat-affected diameter/through-hole diameter is 3.00. Ta.
The aperture diameter and heat-affected diameter were measured using a microscope (VHX-5000 manufactured by Keyence Corporation, lens magnification 200 times).
In addition, when measuring the surrounding area 3g that is affected by heat and is formed around the through hole 3h by laser irradiation, the slanted side surface area when the shape of the through hole 3h is assumed to be a truncated cone shape is measured by the influence of heat. The periphery of the bottom of the truncated conical shape was regarded as the peripheral part 3g affected by heat, and the width of the peripheral part 3g was measured using a microscope to determine the value of r2.

[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 9.7 W, and the angle θ between the insertion direction ILe and the inclined direction ILf was The angle was fixed at 30 degrees, and the hollow protrusion 3 was irradiated once with the laser beam 4L 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 heat-affected peripheral portion 3g formed around the through-hole 3h by laser irradiation is 182 μm, and the ratio of heat-affected diameter/through-hole diameter is 4.55. there were.
That is, when forming the through hole 3h of the same diameter in the hollow protrusion 3 using the laser beam 4L, the laser beam 4L is irradiated from the laser irradiation device 4 with an output that penetrates the adjacent part of the hollow protrusion 3 in one irradiation. The through hole 3h is formed by irradiating the laser beam 4L from the laser irradiation device 4 multiple times with an output that does not penetrate the proximal portion of the hollow protrusion 3 in one irradiation, rather than forming the through hole 3h by doing so. Obviously, the diameter r2 of the peripheral portion 3g can be made smaller.

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

[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, and the angle θ between the insertion direction ILe and the inclined direction ILf was fixed at 30 degrees. Then, the outer surface 32 of the hollow protrusion 3 was irradiated once with a laser beam 4L having an 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 laser irradiation is 30 μm, and the diameter (heat-influenced diameter ) r2 was 80 μm, and the ratio of heat affected diameter/through hole diameter was 2.67.
That is, when forming the through hole 3h of the same diameter in the hollow protrusion 3 using the laser beam 4L, the laser beam 4L is irradiated from the laser irradiation device 4 with an output that penetrates the adjacent part of the hollow protrusion 3 in one irradiation. The through hole 3h is formed by irradiating the laser beam 4L from the laser irradiation device 4 multiple times with an output that does not penetrate the proximal portion of the hollow protrusion 3 in one irradiation, rather than forming the through hole 3h by doing so. Obviously, the diameter r2 of the peripheral portion 3g can be made smaller.
Note that the diameter r1 of the through hole 3h and the diameter r2 of the surrounding portion 3g affected by heat can be measured using a microscope or a scanning electron microscope (SEM).

Table 3 shows the measurement conditions and measurement results of Examples 3 and 4.
In Examples 3 and 4, the laser beam 4L having an output that penetrates the hollow protrusion 3 with an opening diameter smaller than the opening diameter of the through hole 3h in one irradiation is applied multiple times to the hollow protrusion 3 on the same surface of the hollow protrusion 3. The through-hole 3h is formed using the second embodiment in which the through-hole 3h is formed by irradiating a nearby region.
[Example 3]
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 is fixed at 300 μm, the laser output of the laser beam 4L from the UV laser device is fixed at 1.75 W, and the angle θ between the insertion direction ILe and the inclined direction ILf is fixed at 30 degrees. Then, the laser beam 4L was irradiated three times at different locations on the same outer surface 32 of the hollow protrusion 3 with each irradiation time being 5 ms, and the through hole 3h was formed with a total irradiation time of 15 ms. The spot diameter of the laser beam 4L during three irradiations was the same. Here, since the opening diameter (through-hole diameter) r1 of the through-hole 3h is set to 40 μm, the diameter of one spot is 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. At this time, when we measured the diameter (heat-affected diameter) r2 of the surrounding part 3g that was formed around the through-hole 3h and was affected by heat, it was 70 μm, and the ratio of heat-affected diameter/through-hole diameter was 1.75. Ta.

[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 is fixed at 300 μm, the laser output of the laser beam 4L from the UV laser device is fixed at 1.75 W, and the angle θ between the insertion direction ILe and the inclined direction ILf is fixed at 30 degrees. Then, the laser beam 4L was irradiated twice at different locations on the same outer surface 32 of the hollow protrusion 3 with each irradiation time being 45 ms, and the through hole 3h was formed with a total irradiation time of 90 ms. The spot diameter of the laser beam 4L during the two irradiations was the same. Here, since the opening diameter (through-hole diameter) r1 of the through-hole 3h is set to 40 μm, the diameter of one of the plurality of spot diameters is 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 surrounding area 3g formed around the through-hole 3h that was affected by heat was measured and found to be 102 μm, and the ratio of heat-affected diameter/through-hole diameter was 2.55. . As in Examples 1 and 2, the heat-affected diameter and through-hole diameter were measured using a microscope (VHX-5000 manufactured by Keyence Corporation, lens magnification 200 times).

That is, when forming the through hole 3h of the same diameter in the hollow protrusion 3 using the laser beam 4L, the laser beam 4L is irradiated from the laser irradiation device 4 with an output that penetrates the adjacent part of the hollow protrusion 3 in one irradiation. In contrast to the case where the through hole 3h is formed by forming the through hole 3h, the laser irradiation device 4 irradiates the outer surface 32 of the hollow protrusion 3 with a laser beam 4L having an output that penetrates the through hole 3h with an opening diameter r3 smaller than the opening diameter r1 of the through hole 3h. The measurement results showed that the diameter r2 of the heat affected zone was clearly smaller when the through holes 3h were formed by irradiation.
Furthermore, the shapes of the through holes 3h formed in Example 3 and Example 4 are different. That is, in the case of Example 3, by irradiating the laser beam 4L so that the center of the spot diameter is located at each vertex of an equilateral triangle and the spot diameters are adjacent to each other or overlap, the diameter of the laser beam 4L is smaller than that of the through hole 3h. are formed, and these holes are connected to form one through hole 3h. In the case of Example 3, the through hole 3h is approximately circular.
On the other hand, in the case of Example 4, by irradiating the laser beam 4L so that the spot diameter is adjacent to each other in the width direction (X direction) that intersects with the protrusion direction of the hollow protrusion 3, the through-hole Openings having a diameter smaller than 3h are formed, and these are connected to form one through hole 3h. In the case of the fourth embodiment, the through hole 3h is horizontally long and extends in the width direction (X direction).
It is preferable that the irradiation position and number of laser beams 4L be determined according to the size and shape of the through hole 3h that is ultimately desired to be formed.

In this way, when thermoplastic plastic is used as the material for the base sheet 2A, compared to the case where the through holes 3h are formed with one irradiation, the output of one irradiation does not melt and penetrate, but multiple When the base sheet 2A is melted by multiple irradiations and the through holes 3h are formed, the amount of heat given to the base sheet 2A (hollow protrusions 3) can be reduced by one irradiation. Therefore, it can be said that the range of the peripheral portion 3g (heat-affected zone) affected by heat due to irradiation can be reduced, and the strength of the hollow protrusion 3 can be maintained.

On the other hand, as in the second embodiment, when a plurality of holes having a smaller diameter than the through hole 3h are formed on the same surface and the through holes 3h are formed by melting and connecting each hole, the spot By narrowing down the diameter, the output per unit area can be increased, and it is possible to form a penetrating hole having a diameter smaller than that of the through hole 3h, which penetrates the vicinity of the hollow protrusion 3.
In this way, the openings passing through the fine hollow protrusions 3 are formed, and by making the diameter of the openings smaller than that of the through holes 3h, the amount of heat given to the base sheet 2A by one irradiation can be reduced. can be reduced. Therefore, the range affected by heat due to irradiation can be made smaller than the through hole 3h, and the strength of the hollow protrusion 3 can be maintained while being manufactured.

1 Hollow protrusion 2 Base part 2A Base sheet 2D One side of 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 part (outer surface)
r3 Opening diameter formed on the inside r1 Opening diameter formed on the outside T2 Thickness of base material CL Center line

Claims (12)

A method for manufacturing a hollow protrusion, comprising an aperture forming step of forming a through hole in a minute hollow protrusion,
A laser beam having an output that penetrates the hollow protrusion with an aperture diameter smaller than the aperture diameter of the through hole in one irradiation is applied to the hollow protrusion at mutually adjacent areas on the same surface of the hollow protrusion. A method for manufacturing a hollow protrusion, the method comprising forming the through hole by irradiating a plurality of times. 2. The method for manufacturing a hollow protrusion according to claim 1, wherein the through hole is formed by irradiating the laser beam multiple times so as to trace a locus of a triangular apex. The method for manufacturing a hollow protrusion according to claim 1 or 2, wherein the wavelength of the laser beam is 180 nm or more and 20 μm or less. The method for manufacturing a hollow protrusion according to any one of claims 1 to 3, wherein the pulse width of the laser beam is 1 fs or more and 10 ms or less. By irradiating the hollow protrusion with the laser beam multiple times from the outside of the hollow protrusion, the diameter of the aperture formed on the inside of the hollow protrusion becomes larger than that of the aperture formed on the outside of the hollow protrusion. The method for manufacturing a hollow protrusion according to any one of claims 1 to 4, wherein the through hole is formed with a large hole diameter. The method for manufacturing a hollow protrusion according to any one of claims 1 to 5, wherein the planned hole opening position of the hollow protrusion is formed to have a thickness of 0.01 mm or more and 0.7 mm or less. 7. The method for manufacturing a hollow protrusion according to claim 1, wherein the hollow protrusion is made of a material having an ultraviolet transmittance of 60% or more and 95% or less. 8. The method for manufacturing a hollow protrusion according to claim 1, wherein the hollow protrusion is made of a material containing a thermoplastic resin. After the protrusion processing step of forming the hollow protrusion protruding from the other surface of the base sheet by inserting a protrusion-forming convex portion from one side of the base sheet, the opening is performed. The method for manufacturing a hollow protrusion according to any one of claims 1 to 8, wherein the through hole is formed by performing a forming step. A hollow protrusion having a minute hollow protrusion having a through hole,
A hollow protrusion manufactured by the manufacturing method according to any one of claims 1 to 9. The hollow protrusion according to claim 10, wherein a plurality of the through holes are formed in the hollow protrusion. The hollow protrusion according to claim 11, wherein the through hole is formed symmetrically with respect to a center line of the hollow protrusion.

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