JP2021023675A - Manufacturing method for hollow projection tool - Google Patents

Abstract

To provide a manufacturing technology for a hollow projection tool, capable of accurately forming a shape of a minute hollow projection part having an open hole.SOLUTION: A manufacturing method for a hollow projection tool includes: a projection part formation process A of implanting a projection part formation convexity 110 while heating a base material sheet 2A to form a non-penetration hollow projection part 3, and extracting the convexity 110 from the inside of the hollow projection part 3 before forming an open hole 3h, a through hole, on the hollow projection part 3 using non-contact hole opening means 4; and a projection part correction process B of correcting the hollow projection part 3's shape. The projection part correction process B includes: a process of performing heating in a state in which the convexity 110 is inserted inside the hollow projection part 3; a process of performing cooling in the state in which the convexity 110 is inserted inside the hollow projection part 3; and a process of extracting the convexity 110 from the inside of the hollow projection part 3.SELECTED DRAWING: Figure 6

Description

The present invention relates to a method for manufacturing a hollow protrusion having a fine hollow protrusion having a hole.

In recent years, in the medical field, the beauty field, and the like, percutaneous absorption of a drug by a liquid injection tool having fine needle-like protrusions, which is also called a microneedle, has attracted attention. With this injection tool, it is possible to inject a drug into the body by inserting a microneedle into a relatively shallow layer of the skin such as the stratum corneum, and it is a normal syringe while being an invasive drug administration means. It has been noted that the pain felt by the subject is significantly reduced as compared with the above. Among the microneedles, a hollow type microneedle having an opening for communicating the inside and outside of the microneedle is particularly effective because it can expand the choice of agents to be arranged inside the microneedle. However, hollow microneedles having holes are required to have the accuracy of the shape of the microneedles, especially when used in the medical field and the beauty field, and are stable to stably supply the agent to the inside of the skin through the holes. Sex is required.

The hollow microneedle having an opening can be manufactured by, for example, the manufacturing method described in Patent Document 1. In the manufacturing method described in Patent Document 1, a convex mold is inserted from one side of the base sheet while heating the base sheet formed of the thermoplastic resin, and the other surface of the base sheet is inserted. A non-penetrating hollow protrusion projecting from the side is formed, and the hollow protrusion is cooled with the convex shape pierced inside the hollow protrusion, and then the convex shape is removed, and then the base material is used. Using a contact-type convex or non-contact heat processing means (for example, a laser light irradiation device) arranged on the other surface side of the sheet, a hole is opened at a position deviated from the center of the tip portion of the hollow protrusion. It has a step of forming.

Further, in a fine convex structure having a fine convex structure formed by nanoimprint or photolithography, the fine convex structure portion is erected substantially perpendicular to a surface serving as a base of the fine convex structure portion. However, there is a problem that the fine convex structure portion is unintentionally tilted in the manufacturing process of the fine convex structure. As a technique for solving this problem, Patent Document 2 describes the finely convex structure portion by applying energy from the outside to a relatively extending side surface of the inclined fine convex structure portion. It is described that the relatively extending side surface in the above is contracted to correct the inclination of the fine convex structure portion.

JP-A-2017-176655 Japanese Unexamined Patent Publication No. 2014-34160

An object of the present invention is to provide a technique for manufacturing a hollow protrusion that can form a shape of a fine hollow protrusion having a hole with high accuracy with respect to a design.

The present invention is a method for manufacturing a hollow protrusion having fine hollow protrusions having holes, wherein the base sheet formed containing a thermoplastic resin is heated and one side of the base sheet is heated. A convex mold for forming a protrusion is inserted from the base sheet to form a non-penetrating hollow protrusion protruding from the other surface side of the base material sheet, and the convex mold for forming the protrusion is pulled out from the inside of the hollow protrusion. After that, a protrusion forming step of forming the opening, which is a through hole, in the hollow protrusion by using a non-contact type opening means arranged on the other surface side of the base sheet, and the protrusion. A protrusion straightening step for correcting the shape of the hollow protrusion formed in the forming step is provided, and the protrusion straightening step includes the hollow protrusion with a protrusion straightening convex mold inserted inside the hollow protrusion. After the convex insertion heating step of heating the portion, the cooling step of cooling the hollow protrusion with the convex for straightening the protrusion inserted inside the hollow protrusion, and the cooling step, the hollow protrusion This is a method for manufacturing a hollow protrusion, which comprises a release step of removing the protrusion-correcting convex mold from the inside of the portion.

According to the manufacturing method of the present invention, it is possible to efficiently manufacture a high-quality hollow protrusion having a fine hollow protrusion having a hole formed in a shape having a shape with high accuracy with respect to the design.

FIG. 1 is a schematic perspective view of an embodiment of a hollow protrusion manufactured by the manufacturing method of the present invention. FIG. 2 is a schematic cross-sectional view taken along the line II of FIG. FIG. 3 is a diagram showing a configuration of a main part of an embodiment of a manufacturing apparatus that can be used to carry out the method for manufacturing a hollow protrusion shown in FIG. FIG. 4 is a schematic perspective view of a convex embodiment provided in the manufacturing apparatus shown in FIG. FIG. 5 is an explanatory diagram showing a method of measuring the convex tip diameter and tip angle shown in FIG. 6 (a) to 6 (f) are explanatory views of each step of one embodiment of the method for manufacturing a hollow protrusion implemented by the manufacturing apparatus shown in FIG. 3, respectively. 7 (a) to 7 (h) are diagrams for more specifically explaining the manufacturing method shown in FIG.

Hereinafter, the present invention will be described based on the preferred embodiment with reference to the drawings. In the description of the drawings below, the same or similar parts are designated by the same or similar reference numerals. The drawings are basically schematic, and the ratio of each dimension may differ from the actual one.

FIG. 1 shows an embodiment of a hollow protrusion which is a manufacturing object of the manufacturing method of the present invention. As shown in FIG. 1, the hollow protrusion 1 of the present embodiment includes a fine hollow protrusion 3 having an opening 3h and a flat base member 2. The hollow protrusion 1 has a form in which a plurality of hollow protrusions 3 project from the base member 2.

In the hollow protrusion 1 of the present embodiment, a plurality of specifically nine conical hollow protrusions 3 are arranged on the upper surface of the sheet-shaped base member 2. The plurality of hollow protrusions 3 have the same shape and the same dimensions. These plurality (9 pieces) of the hollow protrusions 3 are the flow direction (mechanical direction, hereinafter also referred to as “MD”) at the time of manufacturing the hollow protrusion 1 and the direction orthogonal to the MD at the time of manufacturing (hereinafter, “CD””. (Also referred to as) are arranged in multiple rows (three rows) in each, and in each row, a plurality of (three) hollow protrusions 3 are intermittently arranged at predetermined intervals in one direction. The number, arrangement, and shape of the hollow protrusions 3 are not limited to the form shown in FIG. 1, and can be arbitrarily set. For example, the outer shape of the hollow protrusions 3 is other than the conical shape as shown in FIG. In addition, it can be truncated cone-shaped, columnar, prismatic, pyramidal, pyramidal cone, or the like.

As shown in FIG. 2, each of the plurality of hollow protrusions 3 has an inner surface 31 and an outer surface 32, and has a space 3k defined by the inner surface 31 inside (hollow portion). The space 3k is formed in a shape corresponding to the outer shape of the hollow protrusion 3, and in the hollow protrusion 1 shown in FIG. 1, the space 3k is formed in a conical shape corresponding to the outer shape of the conical hollow protrusion 3. There is. In the space 3k, a base side opening 2h exists on the side opposite to the tip 3t side of the hollow protrusion 3, and the space 3k inside the hollow protrusion 3 is connected to the outside through the base side opening 2h. I'm communicating.

As shown in FIG. 2, the opening 3h is a through hole that penetrates the material for forming the inner surface 31 and the outer surface 32 of the hollow protrusion 3 (same as the material for forming the base member 2) in the thickness direction, and the hollow protrusion 3 The space 3k inside the space 3k communicates with the outside through the opening 3h. The opening length (diameter) of the opening 3h gradually increases from the inner surface 31 toward the outer surface 32. Further, the opening 3h is located on the tip 3t side of the hollow protrusion 3, that is, on the side closer to the tip 3t of the hollow protrusion 3 than the center in the height direction of the hollow protrusion 3 (the same direction as the thickness direction of the base member 2). Although it is located, it is not located at the tip 3t and is formed at a position deviated from the tip 3t (the center of the hollow protrusion 3 in the plan view). When the opening 3h is formed at a position deviated from the tip of the hollow protrusion 3 in this way, the opening 3h is not easily crushed when the hollow protrusion 3 is inserted into the skin, and the inside of the hollow protrusion 3 is hard to collapse. The drug existing in the space 3k can be stably supplied to the inside of the skin through the opening 3h.

The dimensions and the like of each part of the hollow protrusion 1 are not particularly limited, but can be set as follows, for example.
The protrusion height H1 (see FIG. 2) of the hollow protrusion 3 is preferably 0.01 mm or more, more preferably 0.02 mm or more, and preferably 10 mm or less, more preferably 5 mm or less. When the protrusion height H1 is in such a range, when the hollow protrusion 3 is inserted into the skin, it is possible to insert the hollow protrusion 3 into the stratum corneum at the shallowest point and the dermis at the deepest point. Become.
The tip diameter L (see FIG. 2) of the hollow protrusion 3 is preferably 1 μm or more, more preferably 5 μm or more, and preferably 500 μm or less, more preferably 300 μm or less. The tip diameter L of the hollow protrusion 1 is the length at the widest position of the tip 3t of the hollow protrusion 3. When the tip diameter L is in such a range, it becomes difficult to perceive the pain associated with inserting the hollow protrusion 3 into the skin. The tip diameter L is measured by the following method.
Open area in the inner surface 31 of the aperture 3h is good properly is 0.7 [mu] m ² or more, more preferably 20 [mu] m ² or more, and, preferably 200000Myuemu ² or less, more preferably 70000Myuemu ² or less.

<Measuring method of tip diameter L of hollow protrusion 3>
The tip portion (tip 3t and its vicinity) of the hollow protrusion portion 3 is observed using a scanning electron microscope (SEM) or a microscope in a state of being magnified at a predetermined magnification as shown in FIG. 2A. Next, as shown in FIG. 2A, the virtual straight line ILa is extended along the straight line portion on one side side 1a of the side surfaces 1a and 1b of the outer surface 32, and along the straight line portion on the other side side 1b. And extend the virtual straight line ILb. Then, on the tip end side of the hollow protrusion 3, a point where one side side 1a is separated from the virtual straight line ILa is obtained as a first tip point 1a1, and a point where the other side side 1b is separated from the virtual straight line ILb is designated as a second tip point 1b1. Ask. The length L of the straight line connecting the first tip point 1a1 and the second tip point 1b1 obtained in this way was measured using a scanning electron microscope (SEM) or a microscope, and the length of the straight line was measured. Is the tip diameter L of the hollow protrusion 3.

The plurality of hollow protrusions 3 (9 in FIG. 1) have a uniform center-to-center distance in one direction (MD) and a uniform center-to-center distance in the other one direction (CD) orthogonal to the one direction. Is preferable. The "center-to-center distance" here means the distance between the centers (tips 3t) of the two hollow protrusions 3 adjacent to each other in one direction. Further, it is preferable that the distance between the centers in one direction (MD) and the distance between the centers in the other direction (CD) are the same. The distance between the centers of the hollow protrusion 3 in one direction (MD or CD) is preferably 0.01 mm or more, more preferably 0.05 mm or more, and preferably 10 mm or less, more preferably 5 mm or less.

Next, the method for manufacturing the hollow protrusion of the present invention will be described with reference to the drawings, taking the above-mentioned method for manufacturing the hollow protrusion 1 as an example. FIG. 3 shows a main part of the manufacturing apparatus 100, which is an embodiment of the manufacturing apparatus that can be used to carry out the manufacturing method of the hollow protrusion 1. In the drawings such as FIG. 3 used in the explanation of the manufacturing method, the hollow protrusion 3 is exaggerated to be larger than the actual one for convenience of explanation. Further, FIG. 3 shows only the apparatus configuration of the manufacturing apparatus 100, and does not show the manufacturing method of the hollow protrusion of the present invention.

As shown in FIG. 3, the manufacturing apparatus 100 forms a protrusion forming / correcting portion 10 for forming and correcting the hollow protrusion 3, a cooling portion 20, and an opening 3h which is a through hole in the hollow protrusion 3. It is provided with an opening forming portion 40 to be formed. Further, the manufacturing apparatus 100 includes a means (not shown) for transporting the base sheet 2A, which is the raw material of the hollow protrusion 1. The transport means is configured in the same manner as a known transport means capable of transporting a long sheet-like object such as a transport roll.

The base material sheet 2A is a sheet that serves as a base member 2 in the hollow protrusion 1 that is a manufacturing object, and contains a thermoplastic resin. The base sheet 2A is preferably mainly composed of a thermoplastic resin, and specifically, the content of the thermoplastic resin is preferably 50% by mass or more, more preferably 90% by mass or more. Examples of the thermoplastic resin include polyvinyl fatty acid ester, polycarbonate, polypropylene, polyethylene, polyester, polyamide, polyamideimide, polyetheretherketone, polyetherimide, polystyrene, polyethylene terephthalates, polyvinyl chloride, nylon resin, acrylic resin and the like. , And one of these can be used alone or in combination of two or more. Among these, polyfatty acid esters are preferably used from the viewpoint of biodegradability. Specific examples of the polyfatty acid ester include polylactic acid, polyglycolic acid, and combinations thereof. The base sheet 2A may contain 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 (see FIG. 2) of the base member 2 in the hollow protrusion 1 which is the manufacturing object.

The protrusion forming / correcting portion 10 includes a convex shape 110. The convex shape 110 is inserted into the base material sheet 2A to form the hollow protrusion 3 in the protrusion forming step described later, and is formed in the protrusion forming step in the protrusion correction step described later. It is inserted into the hollow protrusion 3 and used to correct the shape of the hollow protrusion 3. That is, the protrusion forming / correcting portion 10 operates in two steps of the protrusion forming step and the protrusion straightening step, and the convex type 110 is used in each step. The outer shape, size, number, and arrangement of the convex 110 correspond to the outer shape, size, number, and arrangement of the hollow protrusions 3 in one hollow protrusion 1 which is a manufacturing object.

As shown in FIG. 4, the convex 110 in the manufacturing apparatus 100 is a part of the convex unit 11. The convex unit 11 includes a flat plate-shaped support member 111 and a convex 110 arranged on one surface of the support member 111. Since the hollow protrusion 1 manufactured by the manufacturing apparatus 100 includes nine conical hollow protrusions 3, the convex unit 11 corresponds to this and has a conical convex on one surface of the support member 111. Nine molds 110 are arranged. Each of the plurality (9) convex shapes 110 is arranged with its tips facing upward. The protrusion forming / correcting portion 10 may be provided with at least a convex shape 110, and the support member 111 may not be provided.

In the manufacturing apparatus 100, the protrusion forming / correcting portion 10 includes the moving means 112 of the convex 110, and by operating the moving means 112, the convex unit 11 including the convex 110 is designated by reference numeral Z in the drawing. The base material sheet 2A (base member 2) shown can be moved to both one side and the other side in the thickness direction. That is, as shown in FIG. 3, the protrusion forming / correcting portion 10 makes the convex unit 11 stand by at a predetermined standby position below the base sheet 2A to be conveyed along the thickness direction Z of the base sheet 2A. The tip 110t of the convex 110 can be brought into contact with the base sheet 2A by moving the convex unit 11 toward the base sheet 2A (upward in FIG. 3), or the convex unit 11 can be brought into contact with the base sheet 2A. It can also be moved in a direction away from (downward in FIG. 3). The moving means 112 may be any as long as it can move the convex 110 (convex unit 11) in this way, and for example, a known electric actuator can be used. The movement of the convex 110 (operation of the moving means 112) is controlled by a control means (not shown) included in the manufacturing apparatus 100.

In the protrusion forming step described later, the base sheet 2A is heated, and in the protrusion straightening step described later, the hollow protrusion 3 is heated. In the manufacturing apparatus 100, the convex unit 11 heats these heating means. (Not shown). The location of the heating means in the convex unit 11 is not particularly limited, and for example, it may be built in the convex 110 or the support member 111, or may be fixed to the surface of the support member 111. The type of the heating means is not particularly limited, and for example, an ultrasonic vibration device, a heating heater, or the like can be used. An ultrasonic vibration device is adopted in the manufacturing apparatus 100, and the heating of the base sheet 2A and the heating of the hollow protrusion 3 are performed by applying ultrasonic vibration via the convex 110, respectively. The operation of the heating means is controlled by a control means (not shown) included in the manufacturing apparatus 100.

The shape of the tip portion (tip 110t and its vicinity) of the convex shape 110 may be a shape corresponding to the outer shape of the hollow protrusion 3 in the hollow protrusion 1 which is the manufacturing object.
The height H2 of the convex 110 (see FIG. 4) is typically the same as or the protrusion height H1 (see FIG. 2) of the hollow protrusion 3 in the hollow protrusion 1 which is the manufacturing object. It is slightly higher than H1. The height H2 of the convex shape 110 is preferably 0.01 mm or more, more preferably 0.02 mm or more, and preferably 30 mm or less, more preferably 20 mm or less.
The tip diameter D1 (see FIG. 5) of the convex 110 is preferably 0.001 mm or more, more preferably 0.005 mm or more, and preferably 1 mm or less, more preferably 0.5 mm or less. The tip diameter D1 is measured by the following method.
The root diameter D2 (see FIG. 5) of the convex 110 is preferably 0.1 mm or more, more preferably 0.2 mm or more, and preferably 5 mm or less, more preferably 3 mm or less.
The tip angle α of the convex shape 110 is preferably 1 degree or more, more than 5 degrees, from the viewpoint of imparting practically sufficient strength to the hollow protrusion 3 in the hollow protrusion 1 which is a manufacturing object. The tip angle α is preferably 60 degrees or less, more preferably 45 degrees or less, from the viewpoint of obtaining the hollow protrusion 3 having an appropriate angle. The tip angle α is measured by the following method.

<Measuring method of tip diameter D1 of convex 110>
The tip of the convex 110 is observed using a scanning electron microscope (SEM) or a microscope in a state of being magnified to a predetermined magnification. Next, as shown in FIG. 5, the virtual straight line ILc is extended along the straight line portion on one side side 11a of the side surfaces 11a and 11b which are the outer surfaces of the convex shape 110, and along the straight line portion on the other side side 11b. And extend the virtual straight line ILd. Then, on the tip side, a point where one side 11a is separated from the virtual straight line ILc is obtained as a first tip point 11a1, and a point where the other side 11b is separated from the virtual straight line ILd is obtained as a second tip point 11b1. The length D1 of the straight line connecting the first tip point 11a1 and the second tip point 11b1 obtained in this way was measured using a scanning electron microscope or a microscope, and the measured length of the straight line was measured as convex. The tip diameter of the mold 110 is D1.

<Measuring method of tip angle α of convex 110>
The tip of the convex 110 is observed using a scanning electron microscope (SEM) or a microscope in a state of being magnified at a predetermined magnification, for example, as a portion surrounded by a square in FIG. Next, as shown in FIG. 5, the virtual straight line ILc is extended along the straight line portion on one side side 11a of the side surfaces 11a and 11b which are the outer surfaces of the convex shape 110, and along the straight line portion on the other side side 11b. And extend the virtual straight line ILd. Then, the angle formed by the virtual straight line ILc and the virtual straight line ILd is measured using a scanning electron microscope or a microscope, and the angle is defined as the tip angle α of the convex 110.

The convex 110 is made of a high-strength material that is hard to break. Examples of the material of the convex 110 include steel, stainless steel, aluminum, aluminum alloy, nickel, nickel alloy, cobalt, cobalt alloy, copper, copper alloy, beryllium copper, beryllium copper alloy and other metals, ceramics and the like. The material of the member other than the convex 110 (for example, the support member 111) in the convex unit 11 may be the same material as the convex 110 (for example, metal or ceramic), or may be a material different from the convex 110 (for example, synthetic resin). ..

In the manufacturing apparatus 100, as shown in FIG. 3, the protrusion forming / correcting portion 10 is a bending suppressing means on the other surface 2U side (upper surface side, opposite to the insertion side of the convex 110) of the base sheet 2A. The first opening plate 12U is provided as a base sheet 2A, and the second opening plate 12D as a bending suppressing means is provided on one side 2D side (lower surface side, insertion side of the convex 110) of the base sheet 2A. The opening plates 12U and 12D face each other with the base sheet 2A interposed therebetween. Each of the opening plates 12U and 12D is formed of a plate-shaped member extending parallel to the MD, and the plate-shaped member is provided with a plurality of openings 12a through which the convex 110 in the convex unit 11 can be inserted. ing. In the opening plates 12U and 12D, the base sheet 2A is supported in a region other than the opening 12a. The material forming the opening plates 12U and 12D may be the same material as the convex type 110 (for example, metal or ceramic), or may be a material different from the convex type 110 (for example, synthetic resin).

The opening plates 12U and 12D are movable in both one side and the other side in the thickness direction Z of the base sheet 2A, respectively. That is, the opening plates 12U and 12D can move from the predetermined standby positions toward the base sheet 2A along the thickness direction Z, come into contact with the base sheet 2A, and move away from the base sheet 2A, respectively. It is also possible to move along the thickness direction Z toward. The movement of the opening plates 12U and 12D is performed by a moving means (not shown) such as an electric actuator, and is controlled by a control means (not shown) included in the manufacturing apparatus 100.

As shown in FIG. 3, the cooling unit 20 includes a cold air blower 21. In the manufacturing apparatus 100, in the cold air blower 21, a blower port 22 for blowing cold air is arranged on the other surface 2U side (upper surface side) of the base sheet 2A, and cold air is blown from the blower port 22 to the hollow protrusion 3 Is designed to cool down. The configuration of the cold air blower 21 is not limited to that shown in FIG. 3, for example, it has a hollow portion through which the strip-shaped base sheet 2A can pass, and the other surface of the base sheet 2A passing through the hollow portion. It may be configured so that cold air can be blown to both the 2U side (upper surface side) and the one side 2D side (lower surface side). The cooling temperature and cooling time of the cold air blower 21 are controlled by a control means (not shown) included in the manufacturing apparatus 100.

As shown in FIG. 3, the hole forming portion 40 is provided with a non-contact type hole opening means 4 on the other surface 2U side (upper surface side) of the base sheet 2A. Examples of the non-contact type opening means 4 include a processing device using a heat source, such as a laser light irradiating device for irradiating laser light, a hot air emitting device for emitting hot air, and a halogen lamp irradiating device for irradiating infrared rays. .. In the manufacturing apparatus 100, the laser light irradiation apparatus 4 is used as the non-contact type opening means 4 from the viewpoint of being able to collect light and control energy with high accuracy required for microfabrication.

As shown in FIG. 3, the laser light irradiation device (non-contact type opening means) 4 includes an irradiation head 41 which is a galvano scanner that freely scans the laser light 4L. The irradiation head 41 is arranged on the other surface 2U side (upper surface side) of the base sheet 2A at a certain interval above the other surface 2U in the thickness direction Z. When the non-penetrating hollow protrusion 3 is irradiated with the laser beam 4L from the irradiation head 41 arranged on the other surface 2U side of the base sheet 2A to form an opening 3h in the hollow protrusion 3, the hollow protrusion 3h is formed. It is difficult for burrs to be formed around the opening 3h on the outer surface 32 (see FIG. 2) of the portion 3. Further, since the opening 3h is easily formed at an arbitrary position of the hollow protrusion 3, it is easy to arbitrarily control the position with respect to the skin surface to which the liquid agent or the like is to be supplied.

As shown in FIG. 3, the irradiation head 41 includes a lens 43 that collects the irradiated laser light 4L, two mirrors 42 that freely scan the focused laser light 4L, and a protective lens 44. The protective lens 44 may not be provided, but it is preferably provided from the viewpoint of preventing dust and dirt from entering the optical system. The mirror 42 is attached to a motor shaft (not shown). The mirror 42 includes a mechanism for moving the irradiation point where the laser beam 4L hits the hollow protrusion 3 on the base sheet 2A to the MD and a mechanism for moving the laser beam to the CD, so that the laser beam 4L can be freely scanned. There is. The lens 43 is movable in the optical axis direction, and is a mechanism for condensing 4L of laser light to make the spot diameter of the irradiation point of the laser light 4L hitting the hollow protrusion 3 constant, irradiation of the laser light 4L. It is provided with a mechanism for moving points in the thickness direction Z of the base sheet 2A. The irradiation head 41 having the mirror 42 and the lens 43 can adjust the irradiation point of the laser beam 4L in three dimensions including the X direction, the Y direction, and the Z direction. Therefore, by digitizing the positions to be irradiated of each of the plurality of hollow protrusions 3 (9 in the illustrated form) in three dimensions, the laser beam 4L is directed to the positions to be irradiated by the hollow protrusions 3 with a predetermined spot diameter. Can be irradiated with. As the laser beam 4L, it is preferable to use one that can be absorbed by the hollow protrusion 3 forming the opening 3h. When the base material sheet 2A forming the hollow protrusion 3 is a sheet such as a film mainly composed of a thermoplastic resin, the laser beam 4L includes a CO ₂ laser, an excimer laser, an argon laser, a YAG laser, and an LD laser ( a semiconductor laser), YVO ₄ laser, it is preferable to use a fiber laser.

FIG. 6 shows an outline of a method for manufacturing the hollow protrusion 1 using the manufacturing apparatus 100. As shown in FIG. 6, the method for manufacturing the hollow protrusion 1 includes a protrusion forming step A and a protrusion straightening step B for correcting the shape of the hollow protrusion 3 formed in the protrusion forming step A. ..

In the protrusion forming step A, while heating the base sheet 2A formed by containing the thermoplastic resin, the convex 110 is inserted from one side 2D side (lower surface side) of the base sheet 2A to insert the base sheet. A non-penetrating hollow protrusion 3 protruding from the other surface 2U side (upper surface side) of 2A is formed (see FIGS. 6 (a) and 6 (b)), and the convex 110 is pulled out from the inside of the hollow protrusion 3. After that, a non-contact type opening means (laser light irradiation device) 4 arranged on the other surface 2U side of the base sheet 2A is used to form a through hole 3h in the hollow protrusion 3 ( 6 (c) and 6 (d)). Hereinafter, the protrusion forming step A will be described with reference to FIGS. 6 and 7.

Prior to the implementation of the protrusion forming step A, as shown in FIG. 3, a long strip-shaped base sheet 2A is unwound from the original roll of the base sheet 2A formed containing the thermoplastic resin to form a unidirectional MD. Transport. Then, when the planned processing portion (the portion scheduled to be formed of the hollow protrusion 3) in the base sheet 2A reaches a predetermined position (protrusion forming / correcting portion 10), the transfer of the base sheet 2A is stopped and at the predetermined position. When the processing of is completed, it is transported again. In this embodiment, the base sheet 2A is intermittently transported in this way.

In the protrusion forming step A, first, as shown in FIG. 7A, the base sheet 2A is sandwiched between the first opening plate 12U and the second opening plate 12D, and the base sheet 2A is on one side 2D side (the first). The convex unit 11 including the convex 110 is moved toward the two-opening plate 12D side), the convex 110 is passed through the opening 12a of the second opening plate 12D, and the tip 110t of the convex 110 is passed through the base sheet 2A. It is brought into contact with one side 2D. The convex type 110 exhibits ultrasonic vibration before the time when it comes into contact with the base sheet 2A by the operation of the ultrasonic vibration device as the heating means described above. In FIGS. 6 and 7, the plurality of wavy lines drawn around the convex 110 indicate a state in which the convex 110 is exhibiting ultrasonic vibration. By bringing the convex 110 on which the ultrasonic vibration is generated into contact with the base sheet 2A, the ultrasonic vibration is applied to the contact portion of the convex 110 on the base sheet 2A, whereby the corresponding contact portion is brought into contact with the base sheet 2A. It is heated and softened. Then, as shown in FIG. 7B, the convex 110 is raised from the one side 2D side (lower surface side) of the base material sheet 2A toward the other side 2U side (upper surface side) while softening the contact portion. Then, the convex 110 is inserted into the base sheet 2A while suppressing the bending of the base sheet 2A by the first opening plate 12U arranged on the other surface 2U side of the base sheet 2A. In this way, a non-penetrating hollow protrusion 3 protruding from the other surface 2U side of the base sheet 2A is formed.

Regarding the application of ultrasonic vibration to the base sheet 2A via the convex shape 110 in the protrusion forming step A, the frequency of the ultrasonic vibration is preferably 10 kHz or more, more preferably 10 kHz or more from the viewpoint of forming the hollow protrusion 3. It is 15 kHz or more, preferably 50 kHz or less, and more preferably 40 kHz or less. From the same viewpoint, the amplitude of the ultrasonic vibration is preferably 1 μm or more, more preferably 5 μm or more, and preferably 60 μm or less, more preferably 50 μm or less. The application of ultrasonic vibration to the base sheet 2A via the convex 110 starts the next step (cooling step described later in this embodiment) before the time when the convex 110 comes into contact with the base sheet 2A. It is preferable to carry out until just before.

In the protrusion forming step A, the heating temperature of the base sheet 2A, more specifically, the heating temperature of the contact portion of the base sheet 2A with the convex 110 is used from the viewpoint of forming the hollow protrusion 3. The base sheet 2A to be subjected is preferably the glass transition temperature or higher and lower than the melting temperature, and particularly preferably the softening temperature or higher and lower than the melting temperature. Specifically, the heating temperature of the base sheet 2A (the contact portion) is preferably 30 ° C. or higher, more preferably 40 ° C. or higher, and preferably 300 ° C. or lower, more preferably 250 ° C. or lower. When a heating heater is used instead of the ultrasonic vibration device as the heating means (heating means provided in the convex unit 11) of the base sheet 2A, the heating temperature of the convex 110 is in the above-mentioned preferable range. The heater may be adjusted as described above. The glass transition temperature (Tg) is measured by the following method, and the softening temperature is measured according to JIS K-7196 "Softening temperature test method by thermomechanical analysis of thermoplastic film and sheet".

<Measurement method of glass transition temperature (Tg)>
The calorific value is measured using a DSC measuring device to determine the glass transition temperature. Specifically, the measuring instrument uses a differential scanning calorimetry device (Diamond DSC) manufactured by Perkin Elmer. Collect 10 mg of the test piece from the base sheet. The measurement conditions are maintained at 20 ° C. for 5 minutes, and then the temperature is raised from 20 ° C. to 320 ° C. at 5 ° C./min to obtain DSC curves of horizontal axis temperature and vertical axis calorie. Then, the glass transition temperature Tg is obtained from this DSC curve.

The "glass transition temperature (Tg) of the base sheet" means the glass transition temperature (Tg) of the constituent resins of the base sheet, and when a plurality of constituent resins are present, the glass transitions of the plurality of types are present. When the temperatures (Tg) are different from each other, the heating temperature of the base sheet by the heating means is preferably at least the lowest glass transition temperature (Tg) among the plurality of glass transition temperatures (Tg), and the plurality of them. It is more preferable that the temperature is equal to or higher than the highest glass transition temperature (Tg) among the glass transition temperatures (Tg). Further, the "softening temperature of the base sheet" is the same as the glass transition temperature (Tg). That is, when there are a plurality of types of constituent resins of the base sheet and the softening temperatures of the plurality of types are different from each other, the heating temperature of the base sheet by the heating means is at least the lowest softening temperature among the plurality of softening temperatures. The above is preferable, and it is more preferable that the softening temperature is the highest among the plurality of softening temperatures. Further, when the base material sheet is composed of two or more kinds of resins having different melting points, the heating temperature of the base material sheet by the heating means is lower than the lowest melting point among the plurality of melting points.

If the insertion speed of the convex 110 into the base material sheet 2A is too slow, the resin is excessively heat-softened, and if it is too fast, the heat softening is insufficient. Therefore, from the viewpoint of efficiently forming the hollow protrusions 3, it is preferable. It is 0.1 mm / sec or more, more preferably 1 mm / sec or more, and preferably 1000 mm / sec or less, more preferably 800 mm / sec or less.
The softening time, that is, "the time until the ascending of the convex mold 110 is stopped and the next step (cooling step in the present embodiment) is performed with the convex mold 110 inserted inside the hollow protrusion 3" is defined as From the viewpoint of compensating for insufficient heating, it is preferably longer than 0 seconds, more preferably 0.1 seconds or more, and preferably 10 seconds or less, more preferably 5 seconds or less.

The insertion height 110h (see FIG. 6B) of the convex shape 110 to be inserted into the base sheet 2A is preferably 0.01 mm or more, more preferably 0., from the viewpoint of efficiently forming the hollow protrusion 3. It is 02 mm or more, preferably 10 mm or less, and more preferably 5 mm or less. The insertion height 110h means the distance between the tip 110t of the convex 110 and the other surface 2U (upper surface) of the base sheet 2A in a state where the convex 110 is deeply inserted into the base sheet 2A. To do. That is, the distance from the other surface 2U to the apex of the convex 110 measured in the vertical direction in the state where the convex 110 is inserted deepest and the convex 110 comes out from the other surface 2U of the base sheet 2A. The insertion height is 110 h.

In the protrusion forming step A of the present embodiment, after the non-penetrating hollow protrusion 3 is formed as described above, as shown in FIG. 7C, the convex 110 is formed inside the hollow protrusion 3. In the stabbed state, the hollow protrusion 3 is cooled by using the cold air blower 21 provided in the cooling section 20 (cooling step). In the cooling step of the protrusion forming step A, the application of ultrasonic vibration via the convex 110 may be continued or stopped, but the shape of the non-penetrating hollow protrusion 3 is not excessively deformed. From the viewpoint of keeping it constant, it is preferable to stop it.

In the cooling step of the protrusion forming step A, the temperature of the cold air blown to the hollow protrusion 3 is preferably −50 ° C. or higher, more preferably −40 ° C. or higher, and preferably 26 ° C. or lower, more preferably 10 ° C. or lower. Is. The cooling time (time for blowing cold air onto the hollow protrusion 3) is preferably 0.01 seconds or more, more preferably 0.5 seconds or more, and preferably 60 seconds from the viewpoint of achieving both moldability and processing time. Below, it is more preferably 30 seconds or less.

When an ultrasonic vibration device is used as the heating means for the base sheet 2A as in the manufacturing apparatus 100, cooling using the cold air blower 21 is not always necessary, and instead of using the cold air blower 21 instead. The hollow protrusion 3 can also be cooled by stopping the operation of the ultrasonic vibrating device. This is one of the advantages of using the ultrasonic vibration device as the heating means, and by using the ultrasonic vibration device as the heating means, it is expected that the device will be simplified and the manufacturing efficiency will be improved. Another advantage of using the ultrasonic vibration device as the heating means is that the ultrasonic vibration is hard to be transmitted to the portion of the base sheet 2A that is not in contact with the convex 110, and therefore is hard to be heated, and the ultrasonic vibration Since cooling can be efficiently performed by turning on / off, there is a point that deformation is unlikely to occur in a portion of the base material sheet 2A other than the portion where the hollow protrusion 3 is planned to be formed.

Next, in the protrusion forming step A, as shown in FIG. 7D, the convex 110 is pulled out from the inside of the non-penetrating hollow protrusion 3 (release step). In the release step of the protrusion forming step A of the present embodiment, the ultrasonic vibration by the ultrasonic vibration device via the convex 110 is stopped, and the moving means 112 is operated to form the convex unit 11 including the convex 110. It is moved in a direction away from the base sheet 2A (hollow protrusion 3), specifically downward.

Next, in the protrusion forming step A, as shown in FIGS. 6 (c) and 7 (e), the non-contact type opening means 4 arranged on the other surface 2U side (upper surface side) of the base sheet 2A Is used to form an opening 3h, which is a through hole, in the non-penetrating hollow protrusion 3 (opening forming step). In the present embodiment, the hole 3h is formed by irradiating the non-penetrating hollow protrusion 3 with the laser light 4L from the laser light irradiation device 4 as the non-contact type hole opening means 4. In the opening opening step, the opening 3h may be formed at the tip 3t of the non-penetrating hollow protrusion 3, but from the viewpoint of reducing damage to the tip 3t when the opening 3h is formed and during use. From the viewpoint of facilitating the insertion of the hollow protrusion 3 into the skin, it is preferable to form the hollow protrusion 3 at a position deviated from the tip of the hollow protrusion 3.

When the laser light irradiation device is used as the non-contact type opening means in the opening forming step of the protrusion forming step A, the opening 3h is formed with a relatively small irradiation energy and the opening 3h is formed. From the viewpoint of maintaining the intensity of the peripheral portion by suppressing the influence of the irradiation energy on the peripheral portion as much as possible, the irradiation time of the laser beam is preferably 0.001 ms or more, more preferably 0.005 ms or more, and preferably 500 ms. Hereinafter, it is more preferably 300 ms or less. From the same viewpoint, the laser output of the laser light is preferably 0.5 W or more, more preferably 1 W or more, and preferably 100 W or less, more preferably 50 W or less.

In the present embodiment, in this way, in the protrusion forming step A, the convex type 110 is pulled out from the non-penetrating hollow protrusion 3, and the hollow protrusion 3 is hollowed out, and the laser beam is applied to the hollow protrusion 3. The holes 3h are formed by irradiation (see FIGS. 6 (c) and 7 (e)), and the laser beam is not irradiated when the convex 110 is inserted inside the hollow protrusion 3. By irradiating the laser beam after making the hollow protrusion 3 hollow in this way, it is possible to minimize the influence of the laser beam on the manufacturing equipment such as the convex 110.

Then, in the present invention, in the protrusion forming step A, a hole 3h is formed in the hollow protrusion 3 by using a non-contact type opening means 4 in a state where the convex 110 is removed from the non-penetrating hollow protrusion 3. After that, it was decided to adopt the protrusion straightening step B for correcting the shape of the hollow protrusion 3 formed in the protrusion forming step A. According to the present invention, as shown in FIG. 6D, the hollow protrusion 3 is bent or curved due to the influence of the heat of fusion or the like when the opening 3h is formed, and the shape is deformed. Even so, by carrying out the protrusion correction step B, it is possible to form the shape of the fine hollow protrusion 3 having the opening 3h with high accuracy with respect to the design.

As shown in FIG. 6, the protrusion straightening step B is a convex insertion heating step of heating the hollow protrusion 3 with the convex 110 inserted inside the hollow protrusion 3 (see FIG. 6E). A cooling step of cooling the hollow protrusion 3 with the convex 110 inserted inside the hollow protrusion 3, and a release step of removing the convex 110 from the inside of the hollow protrusion 3 after the cooling step. (See FIG. 6 (f)).

In the protrusion correction step B of the present embodiment, first, as shown in FIG. 7 (f), the base sheet 2A (base member 2) is sandwiched between the first opening plate 12U and the second opening plate 12D. The convex unit 11 including the convex 110 is moved toward the one side 2D side (second opening plate 12D side) of the base sheet 2A, and the convex 110 is hollowed through the opening 12a of the second opening plate 12D. It is inserted into the hollow portion inside the protrusion 3 and the convex 110 is brought into contact with the inner surface 31 (see FIG. 2) of the hollow protrusion 3 (convex insertion heating step). The convex type 110 exhibits ultrasonic vibration before the time when it is inserted into the hollow protrusion 3 by the operation of the ultrasonic vibration device as the heating means described above. By inserting and abutting the convex 110 on which ultrasonic vibration is generated inside the hollow protrusion 3 in this way, the hollow protrusion 3 is heated and softened, and the outer surface of the convex 110 inserted inside is heated and softened. Transforms to follow. Since the outer shape of the convex 110 inserted inside the hollow protrusion 3 corresponds to the proper outer shape of the hollow protrusion 3, the deformation due to the heat of the hollow protrusion 3 causes the hollow protrusion 3 to be deformed. The shape of the hollow protrusion 3 is corrected.

As described above, the convex insertion heating step of the protrusion straightening step B is a step of inserting a predetermined amount of the convex 110 into the processing target (hollow protrusion 3) at a predetermined speed and heating it, and is a step of heating the protrusion forming step A. It is basically the same as the step of forming the non-penetrating hollow protrusion 3, that is, the step of inserting a predetermined amount of the convex 110 into the processing target (base sheet 2A) at a predetermined speed and heating it. Therefore, the processing conditions (heating temperature, insertion depth of the convex 110 into the hollow protrusion 3 and the insertion speed, etc.) in the convex insertion heating step of the protrusion straightening step B are not set in the protrusion forming step A. It is also possible to make the same processing conditions (heating temperature, insertion depth of the convex 110 into the base sheet 2A, insertion speed, etc.) in the process of forming the through hollow protrusion 3. However, since the purposes of both processes are different from each other, the processing conditions of both processes may be different from each other if more appropriate processing conditions are adopted to achieve the respective purposes.

For example, the processing calorific value conditions may differ between the protrusion forming step A and the protrusion straightening step B. More specifically, for example, the processing heat amount AH applied to the base sheet 2A in the step of forming the non-penetrating hollow protrusion 3 in the protrusion forming step A and the hollow protrusion in the convex insertion heating step of the protrusion straightening step B. It may be different from the processing heat amount BH applied to the part 3. In the present invention, either "processing heat amount AH> processing heat amount BH" or "processing heat amount AH <processing heat amount BH" may be adopted, and the material of the base sheet 2A (hollow protrusion 3) and the hollow protrusion before straightening may be adopted. It may be appropriately selected in consideration of the shape of the portion 3, the material of the convex 110, and the like, but typically, "processing heat amount AH> processing heat amount BH". That is, the processing heat amount BH for straightening the hollow protrusion portion 3 is smaller than the processing heat amount AH for forming the hollow protrusion portion 3.

The processing heat amounts AH and BH can be adjusted by the heating conditions of the heating means of the base sheet 2A to the hollow protrusion 3, as well as the insertion or insertion depth of the convex 110, the insertion or insertion speed, and the like, respectively. it can. When the heating means is an ultrasonic vibration device, the heating conditions include, for example, the frequency and amplitude of ultrasonic waves. When the heating means is a heater, the heating conditions include, for example, the temperature of the heater. For example, when the above "processing heat amount AH> processing heat amount BH" is established, it is preferable to satisfy at least one of the following conditions a to e.

Condition a: The insertion depth of the convex 110 in the hollow protrusion 3 in the convex insertion heating step B is shallower than the insertion depth of the convex 110 into the base sheet 2A in the protrusion forming step A.
Condition b: The insertion speed of the convex 110 in the hollow protrusion 3 in the convex insertion heating step B is slower than the insertion speed of the convex 110 into the base sheet 2A in the protrusion formation step A.
Condition c: When the heating means is an ultrasonic vibrating device, the frequency of ultrasonic waves in the convex insertion heating step B is lower than the frequency of ultrasonic waves in the protrusion forming step A.
Condition d: When the heating means is an ultrasonic vibration device, the amplitude of the ultrasonic wave in the convex insertion heating step B is smaller than the amplitude of the ultrasonic wave in the protrusion forming step A.
Condition e: When the heating means is a heater, the temperature of the heater in the convex insertion heating step B is lower than the temperature of the heater in the protrusion forming step A.

Regarding the condition a, the “penetration depth of the convex 110 into the base sheet 2A in the protrusion forming step A” is the same as the above-mentioned “penetration height 110h” (see FIG. 6B).

Employing the above condition a, the insertion depth of the convex 110 in the hollow protrusion 3 in the convex insertion heating step B is the insertion depth (piercing) of the convex 110 into the base sheet 2A in the protrusion forming step A. When the insertion height is 110 h) or less, that is, when the former ≤ the latter, the ratio of the two is preferably 0.5 or more, more preferably 0.6 or more, and preferably 1.0 as the former / the latter. Hereinafter, it is more preferably 0.99 or less.

When the above condition b is adopted and the insertion speed of the convex 110 in the hollow protrusion 3 in the convex insertion heating step B is set to be equal to or lower than the insertion speed of the convex 110 into the base sheet 2A in the protrusion forming step A. That is, when the former ≤ the latter, the ratio of the two is preferably 0.1 or more, more preferably 0.2 or more, and preferably 1.0 or less, more preferably 0.8 or less as the former / the latter. Is.

Next, in the protrusion straightening step B, as shown in FIG. 7 (g), with the convex 110 inserted inside the hollow protrusion 3, the hollow protrusion is used by using the cold air blower 21 provided in the cooling unit 20. Part 3 is cooled (cooling step). In the cooling step of the protrusion straightening step B, the application of ultrasonic vibration via the convex 110 may be continued or stopped, but the shape of the non-penetrating hollow protrusion 3 is not excessively deformed. From the viewpoint of keeping it constant, it is preferable to stop it. Unless otherwise specified, the cooling step of the protrusion straightening step B can be carried out in the same manner as the cooling step of the protrusion forming step A described above.

Next, in the protrusion straightening step B, as shown in FIGS. 6 (f) and 7 (h), the convex 110 is removed from the inside of the hollow protrusion 3 that has undergone the cooling step (release step). Unless otherwise specified, the release step of the protrusion straightening step B can be carried out in the same manner as the release step of the protrusion forming step A described above. After the release step of the protrusion straightening step B is completed, the precursor 1A (see FIG. 3) of the hollow protrusion 1 is obtained. The precursor 1A is a continuous hollow projection tool in which a plurality of hollow projection tools 1 are connected in a row to the MD.

The precursor 1A of the hollow projection tool 1 formed as described above is conveyed to a cutting portion (not shown) on the downstream side of the MD from the protrusion forming / correcting portion 10, the cooling portion 20, and the opening forming portion 40. Then, it is cut into product units at the cutting portion. In this way, the hollow protrusion 1 shown in FIG. 1 is manufactured. In the hollow protrusion 1, since the shape of the fine hollow protrusion 3 having the opening 3h is formed with high accuracy for the design, the hollow protrusion 3 easily penetrates into the skin, and the agent is applied to the inside of the skin. It can be supplied stably.

By the way, in the above-described embodiment, the same convex shape 110 is used in the protrusion forming step A and the protrusion straightening step B, and the protrusion forming convex mold and the protrusion straightening convex mold are the same. However, the biconvex types may be different from each other. In that case, for example, as a convex type for correcting protrusions (convex type 110 in the protrusion straightening step B), the tip 110t is rounded as compared with the convex type for forming protrusions (convex type 110 in the protrusion forming step A). What is tinged can be used. That is, the convex type for forming the protrusion is sharper than the convex type for correcting the protrusion. In the protrusion forming step A, since it is necessary to pierce and deform the base material sheet 2A with the tip 110t of the convex shape 110, the tip 110t is preferably sharp, but in the protrusion straightening step B, it has already been formed. Since the convex 110 is inserted into the hollow protrusion 3, the tip 110t may be rounded from the viewpoint of not damaging the inside of the hollow protrusion 3.

Although the present invention has been described above based on the preferred embodiment thereof, the present invention is not limited to the above-described embodiment and can be appropriately modified without departing from the spirit of the present invention.

1 Hollow protrusion 1A Precursor of hollow protrusion 2 Base member 2A Base sheet 2D One side (lower surface) of base sheet
Other surface (upper surface) of 2U base sheet
3 Hollow protrusion 3h Opening 3t Tip of hollow protrusion 31 Inner surface of hollow protrusion 32 Outer surface of hollow protrusion 10 Protrusion formation / correction part 11 Convex unit 110 Convex 110t Convex tip 111 Support member 112 Moving means 12U, 12D Opening plate 12a Opening 20 Cooling part 21 Cold air blower 22 Blower 40 Opening part 4 Laser light irradiation device (non-contact type opening means)
41 Irradiation head 4L laser light

Claims (8)

A method for manufacturing a hollow protrusion having a fine hollow protrusion having a hole.
While heating the base material sheet formed containing the thermoplastic resin, a convex mold for forming a protrusion is inserted from one surface side of the base material sheet, and a non-penetrating shape protruding from the other surface side of the base material sheet is inserted. After forming the hollow protrusions of the above and removing the convex mold for forming the protrusions from the inside of the hollow protrusions, a non-contact type opening means arranged on the other surface side of the base material sheet is used. A protrusion forming step of forming the opening which is a through hole in the hollow protrusion,
The protrusion straightening step includes a protrusion straightening step for correcting the shape of the hollow protrusion formed in the protrusion forming step.
A convex insertion heating step of heating the hollow protrusion with the convex for straightening the protrusion inserted inside the hollow protrusion.
A cooling step of cooling the hollow protrusion with the convex shape for correcting the protrusion inserted inside the hollow protrusion.
A method for manufacturing a hollow protrusion, comprising: after the cooling step, a release step of removing the protrusion-correcting convex mold from the inside of the hollow protrusion. The method for manufacturing a hollow protrusion according to claim 1, wherein a laser light irradiation device is used as the non-contact type opening means. The heating of the base material sheet in the protrusion forming step and the heating of the hollow protrusion in the protrusion straightening step are ultrasonic waves via the protrusion forming convex mold or the protrusion straightening convex mold, respectively. The method for manufacturing a hollow protrusion according to claim 1 or 2, which is performed by applying vibration. The method for manufacturing a hollow protrusion according to any one of claims 1 to 3, wherein the convex shape for forming a protrusion is used as the convex shape for correcting the protrusion. The method for manufacturing a hollow protrusion according to any one of claims 1 to 3, wherein the convex shape for correcting the protrusion has a rounded tip as compared with the convex shape for forming the protrusion. The method for manufacturing a hollow protrusion according to any one of claims 1 to 5, wherein the processing heat quantity condition differs between the protrusion forming step and the protrusion straightening step. The insertion depth of the convex shape for straightening the protrusion in the hollow protrusion in the convex insertion heating step is the insertion depth of the convex shape for forming the protrusion into the base material sheet in the protrusion forming step. The method for manufacturing a hollow protrusion according to any one of claims 1 to 6, which is shallower than the above. The insertion speed of the convex shape for correcting the protrusion in the hollow protrusion in the convex insertion heating step is higher than the insertion speed of the convex shape for forming the protrusion into the base material sheet in the protrusion forming step. The method for manufacturing a hollow protrusion according to any one of claims 1 to 7, which is slow.

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