PROJECTION HOLDER MANUFACTURING METHOD AND PROJECTION HOLDER MANUFACTURING APPARATUS

Abstract

To provide a projection-bearing body manufacturing method and a projection-bearing body manufacturing device capable of smoothly drawing out projections from recesses.SOLUTION: Provided is a projection-bearing body manufacturing device EA for manufacturing projection-bearing bodies CB having projections CV formed thereon, comprising: material supporting means 20 for executing a material supporting step of supporting a base material BM by using a supporting member 22 having a supporting surface 22A in which recesses 22B corresponding to projections CV are formed; and pressing means 30 for executing a pressing step of forming the projections CV for forming a projection-bearing body from the plastic material PM by pressing the base material BM in a direction of facing the supporting surface 22A to fill the recesses 22B with a plastic material PM. At least a portion of the supporting member 22, where the recesses 22B are formed, is composed of a swelling member. The device further includes swelling means 90 for executing a step of swelling the supporting member 22.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a method and an apparatus for manufacturing a protrusion holder. [Background technology]

[0002] Techniques for producing a projection holder having needle-like projections formed thereon are known (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-170795 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the manufacturing technology for the protrusion holder disclosed in Patent Document 1, after pressing thermoplastic resin 3 (plastic material) against an intaglio plate 2 (support member) to form a microneedle (protrusion holder), if the protrusion 11 (protrusion) cannot be smoothly removed from the recess of the support member when separating the protrusion holder from the support member, the protrusion will break or become damaged, resulting in the inconvenience that it is not possible to form a protrusion holder of the desired shape.

[0005] An object of the present invention is to provide a method and an apparatus for manufacturing a protrusion holder that enables a protrusion to be smoothly removed from a recess. [Means for solving the problem]

[0006] The present invention employs the configurations set forth in the claims. Effect of the Invention

[0007] According to the present invention, since the support member having swelling properties is caused to swell, the protrusion can be smoothly removed from the recess. [Brief description of the drawings]

[0008] [Figure 1] 1A to 1E are explanatory views of a manufacturing apparatus for a protrusion holder according to one embodiment of the present invention and an explanatory view of the operation of the same apparatus, and FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In this embodiment, the X-axis, Y-axis, and Z-axis are mutually orthogonal, the X-axis and Y-axis are axes in a predetermined plane, and the Z-axis is an axis orthogonal to the predetermined plane. Furthermore, in this embodiment, the view from the front direction in FIG. 1 parallel to the Y-axis is used as a reference, and when directions are indicated without specifying the view, "up" is the direction of the Z-axis arrow, "down" is the opposite direction, "left" is the direction of the X-axis arrow, "right" is the opposite direction, "front" is the front direction in FIG. 1 parallel to the Y-axis, and "rear" is the opposite direction. Note that all of FIGS. 1(B) to (H), which do not include arrows indicating directions, are views from the same direction as FIG. 1(A).

[0010] The manufacturing apparatus for a protrusion holder of the present invention (hereinafter, also simply referred to as the "manufacturing apparatus") EA is an apparatus for carrying out a manufacturing method for a protrusion holder CB having protrusions CV formed thereon, and comprises: material transport means 10 for carrying out a material transport step of transporting a base material BM containing a plastic material PM; material support means 20 for carrying out a material support step of supporting the base material BM with a support member 22 having a support surface 22A on which recesses 22B corresponding to the protrusions CV are formed; pressing means 30 for carrying out a pressing step of pressing the base material BM in a direction towards the support surface 22A to fill the recesses 22B with the plastic material PM, and forming the protrusions CV from the plastic material PM to form the protrusion holder CB; The system is equipped with a heating means 40 that performs a heating process to heat the plastic material PM, a positioning means 50 that performs a positioning process to position the support sheet BS relative to the support surface 22A, a separating means 60 that performs a separating process to separate the protrusion holder CB from the support member 22, a cooling means 70 that performs a cooling process to cool the plastic material PM, a leaching means 80 that performs a leaching process to make the plastic material PM porous by immersing the plastic material PM in water WT as a leaching medium, and a swelling means 90 that performs a swelling process to swell the support member 22, and is arranged in the vicinity of a base material supply means PS that performs a base material supply process to supply the base material BM. The base material BM is formed by laminating a plastic material PM on one side of a support sheet BS. The support sheet BS of this embodiment is made of paper as a transparent member having permeability that allows at least one of liquid and gas to pass through. The plastic material PM has thermoplasticity due to its main component being polylactic acid (PLA), and contains polyethylene glycol PG (see the enlarged view of FIG. 1(D)) as a leaching material that leaches into water WT. The plastic material PM of this embodiment is a mixture of two components, polylactic acid and polyethylene glycol PG, with a weight ratio of 5:5.

[0011] The material conveying means 10 is composed of multiple arms and includes a so-called articulated robot 11 as a driving device that can displace what is supported by the tip arm 11A, which is the working part, to any position and any angle within its working range, and a holding plate 12 supported by the tip arm 11A and having a holding surface 12A that can be adsorbed and held by a pressure reduction means (holding means) not shown, such as a pressure reduction pump or vacuum ejector, and is configured to place the base material BM on the supporting member 22 by abutting the plastic material PM against the supporting surface 22A.

[0012] The material support means 20 comprises a base 21 on which a step 21A is formed, and a support member 22 which is fitted and supported within the step 21A and has a recess 22B formed on a support surface 22A. At least the portion of the support member 22 where the recess 22B is formed is made of a material having swelling properties, and in this embodiment, the entire support member 22 is made of bentonite as a material having swelling properties and has the property of swelling with water.

[0013] The pressing means 30 includes a linear motor 31 as a driving device, and a pressing member 32 supported by an output shaft 31A of the linear motor 31. In this embodiment, the pressing member 32 is made of a transparent material.

[0014] The heating means 40 includes a heating device 41 arranged inside the base 21 and including a coil heater, the heating side of a heat pipe, or the like.

[0015] The positioning means 50 is composed of imaging means such as a camera or a projector, and various sensors such as optical sensors and ultrasonic sensors, and is equipped with a detection device 51 supported on the pressing member 32 via a bracket 51A, an XY table 52 as a driving device, and a rotary motor 53 as a driving device supported on an output base 52A of the XY table 52 and supporting the base 21 with an output shaft 53A, and is configured to move the support member 22 in a straight line or curved direction within the XY plane, and to rotate the support member 22 in the XY plane.

[0016] The separating means 60 is composed of a plurality of arms and includes a so-called articulated robot 61 as a driving device that can displace what is supported by the tip arm 61A, which is the working part, to any position and any angle within its working range, a bracket 62 supported by the tip arm 61A, a linear motor 63 as a driving device supported by the bracket 62, and a holding plate 64 supported by the output shaft 63A and having a holding surface 64A that can be adsorbed and held by a pressure reduction means (holding means) not shown, such as a pressure reduction pump or a vacuum ejector.

[0017] The cooling means 70 includes water WT as a cooling medium and a container 71 for receiving the water WT.

[0018] The brewing means 80 includes water WT as a brewing medium shared with the cooling means 70, and a container 71.

[0019] The swelling means 90 includes an articulated robot 61 and bracket 62 shared with the separating means 60, an suction pad 91 supported on the bracket 62 via an arm 91A and capable of being adsorbed and held by a pressure reducing means (holding means) such as a pressure reducing pump or a vacuum ejector (not shown), water WT as a swelling medium shared with the cooling means 70 and the leaching means 80, and a container 71.

[0020] The operation of the above-mentioned manufacturing apparatus EA for a projection holder will now be described. First, the manufacturing equipment EA in which each member is arranged at the initial position shown by the solid line in Fig. 1(A) is supplied with a base material BM by a user of the manufacturing equipment EA (hereinafter, simply referred to as "user") or a conveying means (not shown), such as an articulated robot or a belt conveyor, on the base material supplying means PS as shown in the figure, and then the user inputs a signal to start automatic operation via an operating means (not shown), such as an operation panel or a personal computer. Then, the material conveying means 10 drives the articulated robot 11 and the pressure reducing means (not shown), moves the holding plate 12 to bring the holding surface 12A into contact with the support sheet BS, and holds the base material BM by suction on the holding surface 12A, and places the base material BM on the support surface 22A of the support member 22 as shown by the two-dot chain line in Fig. 1(A), and then stops driving the pressure reducing means (not shown) to return the holding plate 12 to the initial position. Next, the pressing means 30 drives the linear motor 31 to lower the pressing member 32, and as shown in FIG. 1(B), the pressing member 32 presses the base material BM in the direction toward the support surface 22A, filling the recesses 22B with the plastic material PM. At this time, the heating means 40 drives the heating device 41 to heat and soften the plastic material PM, making it easier to fill the recesses 22B with the plastic material PM. Thereafter, the positioning means 50 drives the detection device 51 to detect the position of the support sheet BS, and based on this detection result, the positioning means 50 drives the XY table 52 and the rotary motor 53 to move the support member 22 so that the recesses 22B (projections CV) are positioned at predetermined positions on the support sheet BS. As a result, the projections CV and the base FD supporting the projections CV are formed from the plastic material PM, and the projection holder CB with the projections CV formed on the support sheet BS is formed. Next, the pressing means 30 drives the linear motor 31 to return the pressing member 32 to the initial position, and then the heating means 40 stops driving the heating device 41 .

[0021] Then, the swelling means 90 drives the articulated robot 61 and the pressure reducing means (not shown) to move the suction pad 91, and as shown in FIG. 1(C), the suction pad 91 suctions and holds the support member 22, and the support member 22 is separated from the base 21. Then, as shown in FIG. 1(D), the support member 22 is immersed in water WT. This causes the support member 22 to swell and soften, and the protrusion CV can be smoothly removed from the recess 22B. In addition, the plastic material PM is cooled by the water WT and shrinks, and as shown in the enlarged view of FIG. 1(D), a gap CL is formed between the plastic material PM and the recess 22B. Furthermore, the polyethylene glycol PG contained in the plastic material PM seeps into the water WT, and as shown in the enlarged view of FIG. 1(D), holes HL are formed in the areas where the polyethylene glycol PG was present, making the plastic material PM porous. Next, the separating means 60 drives the linear motor 63 and the pressure reducing means (not shown), and as shown in Fig. 1(D), the holding plate 64 is moved to suction and hold the protrusion holder CB on the holding surface 64A, and then the holding plate 64 is returned to its initial position, and as shown in Fig. 1(E), the protrusion CV is removed from the recess 22B. Thereafter, the swelling means 90 drives the articulated robot 61, transports the swollen support member 22 to a recovery position (not shown), stops driving the pressure reducing means (not shown), and separates the suction pad 91 from the support member 22. Next, the separating means 60 drives the articulated robot 61, transports the protrusion holder CB with the hole HL formed therein to the next process (not shown), stops driving the pressure reducing means (not shown), and separates the holding plate 64 from the protrusion holder CB. Then, the swelling means 90 drives the articulated robot 61 and a pressure reducing means (not shown), which adsorbs and holds a new support member 22 with the suction pad 91 from a support member stocker (not shown) and transports it. After the new support member 22 is fitted into the step portion 21A of the base 21, the suction pad 91 is returned to its initial position, and the same operations as described above are repeated.

[0022] According to the embodiment described above, since the support member 22 having swelling properties is caused to swell, the protrusions CV can be smoothly removed from the recesses 22B.

[0023] The means and steps in the present invention are not limited in any way as long as they can perform the operations, functions, or steps described for those means and steps, and are not limited at all to the components and steps of a single embodiment shown in the above embodiment. For example, the pressing step may be any step that presses the base material in a direction toward the support surface to fill the recesses with a plastic material, and forms protrusions from the plastic material to form a protrusion holder, and is not limited in any way as long as it is within the technical scope in light of the common general technical knowledge at the time of filing (the same applies to other means and steps).

[0024] The material transport means 10 may be configured to transport the base material BM by sharing the articulated robot 61 with the separating means 60 and the swelling means 90 without adopting the articulated robot 11, or may adopt a suction pad or the like in place of or in combination with the holding plate 12, and may or may not be provided in the protrusion-holding body manufacturing apparatus EA of the present invention.If it is not provided, the base material BM can be transported by other equipment or by hand.

[0025] The material support means 20 may not have a step portion 21A in the base 21, or may be provided with a pressure reducing means such as a pressure reducing pump or vacuum ejector that holds the support member 22, or a support member holding means such as a chuck motor, or for example, a support member 22 may be adopted in which only the portion where the recess 22B is formed is made of a material having swelling properties, or a support member 22 may be adopted in which the portion where the recess 22B is formed and the surrounding portion are made of a material having swelling properties, or the material may be composed only of the support member 22 without the base 21. The support member 22 may be, for example, a highly absorbent polymer that swells and gels with a swelling medium such as liquids such as water or mixed liquids, organic solvents such as ethanol or acetone, or oils such as mineral oil or chemically synthetic oil, and may be, for example, sodium polyacrylate, polyaspartic acid, (starch-acrylic) graft copolymers, (acrylic acid-vinyl alcohol) copolymers, isobutene-maleic anhydride) copolymers, saponified products, polypropylene, as well as water-swellable clays, absorbent polymers, and the number of recesses 22B may be one or more.

[0026] The pressing means 30 may move the support member 22 without or while moving the pressing member 32, and may press the base material BM in a direction toward the support surface 22A to form the protrusion CV, the pressing member 32 may be translucent or may not be transparent, the articulated robot 11 and the holding plate 12 may be shared with the material conveying means 10 without adopting the linear motor 31 and the pressing member 32, or the articulated robot 61, the holding plate 62, the linear motor 63 and holding plate 64 may be shared with the spacing means 60, and the base material BM may be pressed in the direction toward the support surface 22A via holding plate 12 or holding plate 64 to form the protrusion portion CV, or the articulated robot 11 may be shared with the material conveying means 10 without using a linear motor 31, or the articulated robot 61 may be shared with the spacing means 60 and the swelling means 90, and the base material BM may be pressed in the direction toward the support surface 22A via pressing member 32 to form the protrusion portion CV.

[0027] The heating means 40 may be arranged outside the base 21, or inside the support member 22 or inside the pressing member 32, and may heat the plastic material PM before pressing by the pressing means 30, or may heat the plastic material PM while pressing by the pressing means 30, or may heat the plastic material PM after pressing by the pressing means 30, and may or may not be included in the protrusion holder manufacturing apparatus EA of the present invention.

[0028] The positioning means 50 may move at least one of the support member 22 and the pressing member 32 in a straight line or a curved line or may rotate within the XY plane; for example, the support member 22 may move in a straight line or a curved line in the X direction (or Y direction) and the pressing member 32 may move in a straight line or a curved line in the Y direction (X direction); the positioning means 50 may move the support member 22 and the pressing member 32 in a straight line or a curved line in a direction other than the X or Y direction; it may simply move the support member 22 and the pressing member 32 in a straight line or a curved line within the XY plane; or it may simply move the support member 22 and the pressing member 32 in a rotational line within the XY plane. The detection device 51 may be a single unit or two or more units, and may detect the position of the support sheet BS relative to the support surface 22A from the side of the pressing member 32, or the base 21 and the support member 22 may be made of transparent or semi-transparent materials so that the position of the support sheet BS relative to the support surface 22A can be detected by looking through the base 21 and the support member 22, or the detection device 51 may not be supported by the pressing member 32. The positioning means 50 may position the plastic material PM relative to the support surface 22A, or may position both the support sheet BS and the plastic material PM relative to the support surface 22A, and may or may not be provided in the protrusion holder manufacturing apparatus EA of the present invention.

[0029] The separating means 60 may be configured so that the articulated robot 61 or the like is not shared with the swelling means 90, and the holding plate 64 is moved by a driving device or the like independent of the swelling means 90 to separate the protrusion holder CB from the support member 22, or the articulated robot 11 may be shared with the material conveying means 10 without adopting the articulated robot 61, and the protrusion holder CB may be separated from the support member 22, or a peeling tape may be attached to the protrusion holder CB, and tension may be applied to the peeling tape to separate the protrusion holder CB from the support member 22, or a vibrator may be used. Alternatively, a vibration means such as a centrifugal separator or an ultrasonic vibrator may be employed to apply vibration to the protrusion holder CB to make it easier to separate the protrusion holder CB from the support member 22, or the protrusion holder CB may be centrifuged, or when the protrusion holder CB is immersed in water WT, the protrusion holder CB may be moved or vibrated to make it easier to leach the polyethylene glycol PG into the water WT, and this may or may not be provided in the protrusion holder manufacturing apparatus EA of the present invention, and if it is not provided, the protrusion holder CB can be separated from the support member 22 by other equipment or by hand.

[0030] The cooling means 70 may be configured to cool the plastic material PM by immersing the plastic material PM in a cooling medium such as water or a mixed liquid, an organic solvent such as ethanol or acetone, or an oil such as mineral oil or chemically synthetic oil, or the cooling medium may be a different medium from the one used as the leaching medium in the leaching means 80, or the cooling medium may be a different medium from the one used as the swelling medium in the swelling means 90, or a cooling medium consisting of a Peltier element or the cooling side of a heat pipe, etc. may be used as the cooling medium, and the cooling medium may be provided inside at least one of the base 21, the support member 22, the pressing member 32 and the retaining plate 64, or may be provided outside them, or the plastic material PM may be cooled by applying air or cold air, etc. to the plastic material PM, and may or may not be provided in the protrusion holder manufacturing apparatus EA of the present invention.

[0031] The leaching means 80 may use any leaching medium that can leach the leaching material contained in the base material BM, such as liquids such as water or mixed liquids, organic solvents such as ethanol or acetone, or oils such as mineral oil or chemically synthetic oil.The leaching medium may be made of a material other than the cooling medium used in the cooling means 70, or the leaching medium may be made of a material other than the swelling medium used in the swelling means 90.The leaching medium may be moved, circulated, vibrated or stirred to make it easier to leach the leaching material into the leaching medium, and may or may not be provided in the protrusion holder manufacturing apparatus EA of the present invention.

[0032] The swelling means 90 may be configured to hold the support member 22 with a chuck motor, chuck cylinder, or the like, instead of or in combination with the suction pad 91, and any swelling medium may be used as long as it is capable of swelling the swelling material used in the support member 22, such as a liquid such as water or a mixed liquid, an organic solvent such as ethanol or acetone, or an oil such as mineral oil or chemically synthetic oil.The swelling medium may be a material other than the cooling medium used in the cooling means 70, or a material other than the leaching medium used in the leaching means 80.The suction pad 91 may be moved by a driving device or the like independent of the spacing means 60, without sharing the articulated robot 61 and bracket 62 with the spacing means 60.

[0033] The base material supply means PS may be a simple table, a belt conveyor, or a self-propelled transport table, etc., and may or may not be provided in the protrusion-retaining body manufacturing apparatus EA of the present invention.

[0034] The protrusion holder manufacturing apparatus EA may form the protrusion portion CV by pressing the base material BM in a direction toward the support surface 22A in a fluid atmosphere, for example, a gas such as an elemental gas or a compound gas, a liquid such as water or a mixed liquid, an organic solvent such as ethanol or acetone, or an oil such as mineral oil or chemically synthetic oil. In the above embodiment, the three steps of the cooling process for cooling the plastic material PM, the leaching process for converting the plastic material PM into a porous body, and the swelling process for swelling the support member 22 were carried out simultaneously by immersing the protrusion holder CB in water WT, but these three steps may be carried out separately, or any two of the three steps may be carried out simultaneously and the remaining step may be carried out separately.

[0035] The support sheet BS may be made of any material that is permeable to at least one of liquid and gas, such as cloth, nonwoven fabric, resin, mesh material, wood, etc., as well as metal, resin, silicone material, rubber material, wood, paper, ceramics, etc. with through holes formed therein, or may be made of a material that is not permeable to liquid and gas (i.e., not a permeable material), such as metal, resin, silicone material, rubber material, wood, paper, ceramics, etc.

[0036] The plastic material PM is a material that deforms when energy such as heat or pressure is applied to it and does not return to its original shape. Examples of the plastic material PM include metal, clay, resin, etc. In the case of resin, it can be any material that has plasticity, such as PET, polypropylene, polyethylene, polyvinyl chloride, poly(lactide-co-glycolide) copolymer (PLGA), etc., and it can be made of a single component or multiple components, can be composed only of materials that have plasticity, or can be composed of materials that have plasticity and materials that do not have plasticity, can have no thermoplasticity, can not contain leaching materials, or can contain a thermoplastic resin as a material that has thermoplasticity. The ratio of the plastic material PM to the leaching material may be any ratio other than 5:5, such as 8:2 or 1:9, and the basis for these ratios may be any ratio other than weight ratio, such as mass ratio, volume ratio, molar ratio, etc. The leaching material can be anything that will leach into the leaching medium, such as, for example, sodium chloride, potassium nitrate, alum, polyvinyl alcohol, etc. The base material BM may be composed only of plastic material PM without the support sheet BS, or it may have other materials laminated thereon in addition to the support sheet BS and the plastic material PM, and the amount of plastic material PM may be the same as the capacity of the recess 22B or may be greater than the capacity of the recess 22B. The height of the protrusions CV may be 100 nm to 3 mm, or may be 100 nm or less, or may be 3 mm or more. In particular, when used as a so-called microneedle, the height of the protrusions CV is preferably 100 μm to 1.5 mm. The tip of the protrusion CV may be sharp or blunt, may be rounded, may be arrowhead-shaped, or may be bifurcated or branched into three or more prongs. The shape of the protrusion CV may be a cone, a pyramid, a cylinder, a prism, or a combination thereof.

[0037] The protrusion holder CB may be one in which only the protrusion portion CV is formed from a plastic material PM and the protrusion portion CV is directly supported by the support sheet BS, as shown in Figure 1(F), or one in which the protrusion portion CV and base FD are formed from a plastic material PM and the base FD is embedded (permeated) into the support sheet BS, as shown in Figure 1(G), or one in which the protrusion portion CV and base FD are formed from a plastic material PM and are not supported by the support sheet BS, as shown in Figure 1(H).

[0038] The driving equipment in the above-described embodiments may be electric equipment such as a rotary motor, a linear motor, a single-axis robot, or a multi-joint robot having joints on two or more axes, or an actuator such as an air cylinder, a hydraulic cylinder, a rodless cylinder, or a rotary cylinder, or a direct or indirect combination of these may also be used. In the above-described embodiments, when a pressing means or pressing member such as a pressing roller or a pressing head is used to press an object to be pressed, a roller, a round bar, a blade material, a brush-like member, or a member that blows air or a gas may be used instead of or in combination with the above-described examples. The pressing means may be made of a deformable material such as rubber, resin, sponge, or may be made of an indeformable material such as metal or resin. When a supporting (holding) means or a supporting (holding) member that supports (holds) a supported member (held member) is used, a gripping means such as a mechanical chuck or a chuck cylinder, Coulomb force, adhesive (adhesive sheet, adhesive tape), pressure sensitive adhesive (adhesive sheet, adhesive tape), magnetic force, Bernoulli adsorption, suction adsorption, driving equipment, or the like may be used to support (hold) the supported member. [Explanation of symbols]

[0039] EA… Manufacturing equipment for projection holders 20...Material support means 22...Support member 22A…Support surface 22B…Concave 30...Pressing means 80...Leaching means 90...Swelling means BM…Base material CB…Protrusion holder CV…Protrusion PG…Polyethylene glycol (leaching material) PM…Plastic material WT…Water (leaching medium)

Claims

1. A method for manufacturing a projection holder having a projection formed thereon, comprising the steps of: a material supporting step of supporting a base material including a plastic material with a supporting member having a supporting surface on which recesses corresponding to the protrusions are formed; a pressing step of pressing the base material in a direction toward the support surface to fill the recess with the plastic material and form the protrusion from the plastic material to form the protrusion holder; the support member is made of a material having swelling properties at least in a portion where the recess is formed, A method for manufacturing a projection-retaining body, comprising the step of swelling the support member after the pressing step.

2. The plastic material comprises a leaching material that is leached into a leaching medium; 2. The method for manufacturing a projection-retaining body according to claim 1, further comprising the step of: immersing said plastic material in said leaching medium after said pressing step, thereby carrying out a leaching step of making said plastic material porous.

3. A manufacturing device for a projection holder having a projection formed thereon, a material supporting means for supporting a base material including a plastic material, the base material being a supporting member having a supporting surface on which recesses corresponding to the protrusions are formed; a pressing means for pressing the base material in a direction toward the support surface to fill the recess with the plastic material and form the protrusion from the plastic material to form the protrusion holder; the support member is made of a material having swelling properties at least in a portion where the recess is formed, A manufacturing apparatus for a projection-retaining body, comprising swelling means for swelling the support member.

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