Injection needle

Abstract

Provided is an injection needle having fine first and second protrusions (11, 12) protruding from a sheet base (2), the first protrusion (11) having a tapered shape and having an open hole (11a) at the tip, the second protrusion (12) not having an open hole at the tip, the protrusion height of the first protrusion and the second protrusion being 5000 [mu] m or less, and the protrusion height of the first protrusion and the second protrusion being 5000 [mu] m or less in plan view. The first region (R1) includes one or more first protrusions (11), and the second region (R2) includes two or more second protrusions (12) and sandwiches or surrounds the first region (R1), and the distance (D1), which is the shortest distance among the distances between the first protrusions (11) and the second protrusions (12), is 2.0-10 mm (inclusive).

Description

Technical Field

[0001] The present invention relates to an injection needle. Background Art

[0002] In recent years, in the medical field, the cosmetic field, etc., intradermal administration of a liquid such as a drug using an injection needle having fine needle-like protrusions also called microneedles or the like has attracted attention. With this injection needle, it is possible to insert the microneedles into a relatively shallow layer of the skin such as the stratum corneum and inject a liquid into the body, and compared with a normal syringe, the pain felt by the subject is significantly reduced, so it is attracting attention as a low-invasive liquid delivery component.

[0003] In Patent Document 1, a connection assembly (hub assembly) is described that has a columnar limiter with microneedles protruding therefrom and a stabilization ring that surrounds the microneedles and the limiter. The limiter is used to control the insertion depth of the microneedles into the skin. The stabilization ring is used to suppress deformation of the skin when the microneedles are inserted into the skin. The connection assembly has a mounting mechanism and is fixed to a drug delivery device via this mounting mechanism.

[0004] In Patent Document 2, a microneedle sheet having a plurality of micro-sized needle pads protruding from the surface is described. In this document, it is described that the needle pad has a through needle pad formed with a through hole penetrating from the front side to the back side, and a dummy needle pad not formed with the through hole.

[0005] Prior Art Documents

[0006] Patent Documents

[0007] Patent Document 1: WO2007061972A2

[0008] Patent Document 2: International Publication No. 2021 / 177317 Summary of the Invention

[0009] The present invention relates to an injection needle.

[0010] In one embodiment, it preferably has fine first protrusions and second protrusions protruding from the sheet base.

[0011] In one embodiment, it is preferable that the first protrusion has a conical shape and has an opening at the tip.

[0012] In one embodiment, it is preferable that the second protrusion does not have an opening at the tip.

[0013] In one embodiment, it is preferable that in a plan view, it has a first region including one or two or more first protrusions, and a second region including two or more second protrusions that sandwich or surround the first region.

[0014] In one embodiment, it is preferable that the shortest distance, i.e., distance D1, between the first protrusion and the second protrusion is 2.0 mm or more and 10 mm or less. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 is a perspective view of an injection needle according to a preferred embodiment of the present invention.

[0016] Figure 2 is Figure 1 a top view of the injection needle shown.

[0017] Figure 3 (a) of Figure 2 is an A-A cross-sectional view of Figure 3 (b) of Figure 2 is a B-B cross-sectional view of Figure 3 (c) of Figure 2 is a C-C cross-sectional view of

[0018] Figure 4 schematically shows Figure 1 a top view of the arrangement pattern (arrangement mode) of the protrusions in the injection needle shown.

[0019] Figure 5 schematically shows Figure 1 a view of the usage state of the injection needle shown.

[0020] Figure 6 (a) to (d) of Figure 4 are top views showing other preferred embodiments of the present invention and are corresponding to

[0021] Figure 7 is a cross-sectional view of the second protrusion showing other preferred embodiments of the present invention.

[0022] Figure 8 (a) and (b) of

[0023] Figure 9 (a) of Figure 9 is a top view schematically showing the arrangement pattern of the protrusions in the injection needle of Comparative Example 1,

[0024] Figure 10 is a top view schematically showing the arrangement of the protrusions of the injection needle for evaluating the relationship between the liquid volume and the radius of the raised rash.

[0025] Figure 11 is a top view schematically showing the major axis and minor axis of the raised rash measured in the evaluation of the relationship between the liquid volume and the radius of the raised rash.

[0026] Figure 12 It is a graph showing the evaluation results of the relationship between the liquid volume and the radius of the raised rash. Detailed implementation mode

[0027] As an injection method capable of efficiently taking in antigens, intradermal injection has attracted much attention. According to reports by the World Health Organization and others, based on intradermal injection, compared with intramuscular injection and subcutaneous injection, the amount of vaccine required for one vaccination can be reduced to one-fifth. However, it is known that in existing injection needles, a large amount of training is required to master the technique of intradermal administration. In order to facilitate intradermal administration, intradermal administration of liquids such as drugs using an injection needle having fine needle-like protrusions also known as microneedles has attracted attention. However, in existing microneedles, due to the raised rash formed when injecting liquids such as drugs into the dermis, it is sometimes difficult to appropriately inject the liquid into the dermis. Hereinafter, this will be described in detail.

[0028] When a microneedle is inserted into the skin to inject a liquid into the dermis, the injected liquid causes the skin to bulge, forming a raised rash (refer to Figure 8 (a) of ). When the injection needle has protrusions 82 other than the microneedle 81 for injecting liquid, such as the stabilization ring of Patent Document 1 and the dummy needle pad of Patent Document 2, these protrusions 82 may inhibit the bulging of the skin (refer to Figure 8 (b) of ). As a result, for example, in the case of a large injection volume, etc., it may be difficult for the liquid to enter the body, or there may be a liquid injection failure such as liquid leakage. As such, in Patent Documents 1 and 2, it may be difficult to inject the liquid.

[0029] The present invention relates to an injection needle that, when injecting a liquid into the skin using the injection needle, is less likely to inhibit the skin from bulging due to the injected liquid and can efficiently inject the liquid.

[0030] Hereinafter, the present invention will be described with reference to its preferred embodiments.

[0031] The injection needle 1 of the present invention has protrusions protruding from the sheet base 2. The sheet base 2 is a sheet-like portion connecting the protrusions. When protrusions are formed on the base sheet to form the injection needle 1, the portion other than the protrusions in the injection needle 1 is the sheet base 2.

[0032] Typically, the injection needle 1 has a flat sheet-like shape as a whole, and has a sheet base 2 and a plurality of protrusions protruding from one surface of the sheet base 2.

[0033] Typically, the injection needle 1 has a protrusion arrangement region in which protrusions are arranged in a dispersed state in the plane direction.

[0034] Typically, the protruding configuration region includes a first region R1 and a second region R2 described later.

[0035] The protrusions of the injection needle 1 preferably include: a first protrusion 11 having a conical shape and having an opening 11a at the front end; and a second protrusion 12 not having an opening at the front end. This example is shown in Figure 1 . In Figure 1 the example shown, the first protrusion 11 and the second protrusion 12 are fine protrusions, preferably fine protrusions with a protrusion height of 5000 μm or less.

[0036] The conical shape of the first protrusion 11 is typically a substantially conical shape, but it can also be a polygonal pyramid such as a quadrangular pyramid. The substantially conical shape includes, in addition to the conical shape, an eccentric conical shape where the center and the front end of the protrusion are at different positions.

[0037] The first protrusion 11 is preferably a fine protrusion having a hollow portion 11b, that is, a so-called microneedle (refer to Figure 3 (a)).

[0038] The second protrusion 12 can be hollow or solid. In Figure 1 the example shown, the second protrusion 12 is solid (refer to Figure 3 (b) and (c)). By making the second protrusion 12 solid, when injecting a liquid such as a drug from the injection needle 1, the amount of the drug remaining in the injection needle 1 can be reduced.

[0039] As Figure 1 shown, the second protrusion 12 preferably has: a stimulating protrusion 32 having a conical shape; and a piercing depth control protrusion 33 having a columnar shape with the front end face being a piercing depth control portion 40 (hereinafter, also referred to as "control protrusion").

[0040] The front end face of the control protrusion 33 is preferably flat, that is, a straight line extending in the horizontal direction, or a curved line convex in the protruding direction of the control protrusion 33.

[0041] The conical shape of the stimulating protrusion 32 is the same as that of the first protrusion 11, and can be a substantially conical shape or a polygonal pyramid. In addition, the columnar shape of the control protrusion 33 can be a cylindrical shape or a polygonal prism shape such as a quadrangular prism.

[0042] The injection needle 1 preferably includes, as the second protrusion 12, a stimulating protrusion 32 having a conical shape or a control protrusion 33 having a columnar shape, and more preferably includes both.

[0043] The injection needle 1 preferably has a first region R1 including one or more than two first protrusions 11 when viewed from above. The first region R1 is preferably located in the central region of the sheet base 2 when viewed from above. The central region is, for example, a circular region with a diameter that is one-third, preferably one-half, of the diameter of the sheet base 2. In the illustrated example, the center of the sheet base 2 coincides with the center of the first region R1, but the centers may be offset from each other.

[0044] The first protrusion 11 included in the first region R1 may be one or more than two. The plurality of first protrusions 11 are preferably arranged to form an arbitrary shape as a whole. For example, the plurality of first protrusions 11 are preferably arranged in a triangle (see Figure 2 ), a circle (see Figure 6 (a)), or a straight line (see Figure 6 (d)).

[0045] The plurality of first protrusions 11 are preferably arranged such that the imaginary line C1 connecting the centers of the first protrusions 11 is circular when viewed from above (see Figure 2 , Figure 6 (a) and Figure 6 (c)). Here, "circular" means a closed shape, including not only a circle but also a polygonal shape, etc. When the first protrusions 11 are arranged such that the imaginary line C1 connecting the centers of the first protrusions 11 is circular, it is preferable that there are no first protrusions 11 that entirely exist within the region surrounded by the imaginary line C1.

[0046] In the Figure 2 illustrated injection needle 1, the centers of the plurality of first protrusions 11 are located on the same circle.

[0047] The injection needle 1 preferably has a second region R2 including two or more second protrusions 12. Preferably, the second region sandwiches or surrounds the first region R1. In the example shown in Figure 2 , the second region R2 surrounds the first region R1.

[0048] The second protrusions 12 included in the second region R2 are preferably arranged such that the imaginary line connecting the centers of the second protrusions 12 is circular when viewed from above. For example, the second protrusions 12 may be circular with the imaginary line C2 connecting the centers of the second protrusions 12 being circular (see Figure 4 and Figure 6 (a)), a quadrilateral ring (see Figure 6 (b)), or a triangular ring (see Figure 6 (c)). In the injection needle 1 shown in Figure 2 , the centers of the plurality of second protrusions 12 are located on the same circle.

[0049] Figure 6An example where the second region R2 sandwiches the first region R1 is shown in (d). When the second region R2 sandwiches the first region R1, it is preferable that the first region R1 does not extend from the second region R2.

[0050] Next, the first region R1 and the second region R2 will be described in detail.

[0051] As Figure 2 and Figure 6 shown in (a) of , when a plurality of first protrusions 11 are concentrated in the central region of the sheet base 2 in a top view, the region inside the smallest circle surrounding the plurality of first protrusions 11 is the first region R1.

[0052] As Figure 2 and Figure 6 shown in (a) of , when a plurality of second protrusions 12 are arranged so as to surround the first region R1, the region between the smallest circle surrounding the plurality of second protrusions 12 and the largest circle inscribed in the plurality of second protrusions 12 is the second region R2.

[0053] When instead of a plurality of first protrusions 11, a single first protrusion 11 exists in the central region of the sheet base 2 in a top view, the region inside the smallest circle surrounding the first protrusion 11 is taken as the first region R1.

[0054] When a plurality of second protrusions 12 are arranged in a polygonal shape so as to surround a plurality of first protrusions 11 concentrated in the above central region, or in a polygonal shape so as to surround a single first protrusion 11 existing in the above central region, the region inside the smallest shape that is a similar shape to the polygonal shape and surrounds the plurality of first protrusions 11 can also be taken as the first region R1 (refer to Figure 6 of (b) and (c)).

[0055] When a plurality of second protrusions 12 are arranged in a polygonal shape, the region between the smallest line that is a similar shape to the polygonal shape and surrounds the plurality of second protrusions 12, and the largest line that is a similar shape to the polygonal shape and is inscribed in the plurality of second protrusions 12 in a top view is taken as the second region R2 (refer to Figure 6 of (b) and (c)).

[0056] When a plurality of first protrusions 11 are arranged in a row in one direction, the region inside the smallest rectangle surrounding the plurality of first protrusions 11 is the first region R1 (refer to Figure 6 of (d)).

[0057] When a plurality of second protrusions 12 are arranged so as to sandwich the first region R1 (refer to Figure 6In (d) thereof, the region inside the smallest rectangle surrounding the second protrusions 12 respectively disposed on both sides of the first region R1 is the second region R2.

[0058] The injection needle 1 has an opening 11a in the first protrusion 11 and becomes a liquid injection device capable of being used for intradermal administration of liquids such as pharmaceuticals.

[0059] Typically, an opening 11a is formed at the front end of the first protrusion 11, and the hollow portion 11b of the first protrusion 11 communicates with the outside through this opening 11a. The opening 11a is a through-hole that penetrates the base material sheet of the first protrusion 11 in the thickness direction and is preferably located at the front end of the conical first protrusion 11. The hollow portion 11b of the first protrusion 11 functions as a storage portion or a passage for the liquid discharged from the opening 11a to the outside. Here, the front end of the first protrusion 11 refers to the region on the front end side of the middle position of the protrusion height H1 from the surface of the sheet base 2 to the front end of the first protrusion 11. Figure 3 This specific example is shown in (a) thereof.

[0060] When the injection needle 1 is used for intradermal administration of a pharmaceutical, the front end of the first protrusion 11 is inserted into the skin S, and the liquid pharmaceutical L stored in the hollow portion 11b of the first protrusion 11 is injected into the skin S from the opening 11a at the front end (refer to Figure 5 ). In this way, the hollow portion 11b of the first protrusion 11 functions as a storage portion for the pharmaceutical, and typically there is no case where the pharmaceutical is supplied from the outside.

[0061] When supplying the pharmaceutical from the outside, for example, in the case of using a pharmaceutical supply device such as a syringe (not shown) together with the injection needle 1, the hollow portion 11b functions as a passage for the pharmaceutical. The pharmaceutical supply device may also be a structure in which a sheet-like member is disposed on the back side of the injection needle 1, a pharmaceutical storage space is formed between the back side of the injection needle 1 and the sheet-like member, and the pharmaceutical is supplied to the first protrusion 11 by pressing the sheet-like member (refer to Japanese Patent Application Laid-Open No. 2020-096790

[0011] ).

[0062] In the injection needle 1, the shortest distance D1 among the distances between the first protrusion 11 and the second protrusion 12 (refer to Figure 4 ) is preferably 2.0 mm or more and 10 mm or less. The advantages of the above distance D1 within the above range are as follows.

[0063] When the front end of the first protrusion 11 is inserted into the skin S and the pharmaceutical L is injected into the skin S, the injected pharmaceutical L causes the skin to bulge, forming a bulging rash 9 (refer to Figure 5)。At this time, by making the above-mentioned distance D1 within the above range, it is possible to prevent the second protrusion 12 from suppressing the swelling of the skin. That is, the skin is prone to swelling. Thus, for example, even in the case of a large injection volume or the like, the liquid such as the medicine L can easily enter the body, and the liquid can be injected efficiently and without omission. The inventor studied the relationship between the volume V of the liquid injected into the skin S and the radius R of the raised rash formed by the following method.

[0064] <Relationship between liquid volume and radius of raised rash>

[0065] The excised skin (male, 6-week-old, ventral part; Oriental Yeast Co., Ltd.) of Göttingen minipigs stored at -20°C was transferred to a refrigerator (4°C) and thawed one day before the experiment. The excised skin was placed on 5 to 7 sheets of wiping paper towels (Kimtowel), restored to room temperature, shaved using a razor, and used for drug administration after wiping the surface with an alcohol swab.

[0066] Rhodamine B powder (Sigma-Aldrich) was adjusted to 0.5 mg / mL with ultrapure water and filled into a microsyringe (Agilent). The microsyringe and the injection needle were connected to form an injection device. Then, the injection device was installed on the puncture device and air was exhausted. The liquid volume in the microsyringe was set to 10, 25, 50, 100, or 250 μL, and the excess liquid attached to the injection needle was absorbed and removed by a wiping paper. The configuration of the protrusions of the injection needle is as Figure 10 shown. The height H1 of the first protrusion 11 of the injection needle is 2.0 mm, the height H2 of the stimulating protrusion 32 is 1.4 mm, and the height H3 of the control protrusion 33 is 0.9 mm. The shortest distance D1 between the first protrusion 31 and the second protrusion 12 is 2.2 mm. The radius D2 of the imaginary circle formed by the imaginary line C1 connecting the centers of the first protrusions 11 is 0.75 mm.

[0067] The injection needle was vertically punctured into the skin using the puncture device, and an appropriate amount of rhodamine B aqueous solution was administered intradermally. After administration, the injection needle was withdrawn, and immediately the outline of the raised rash (the area that is whiter than the surroundings and appears raised) was traced with a marker pen, and the length A of the major axis and the length B of the minor axis of the raised rash were measured using a vernier caliper. Figure 11 The figure schematically shows a top view of the raised rash. Figure 11 In the figure, reference numeral 91 indicates the outline of the raised rash, and reference numeral 92 indicates the liquid within the raised rash. Each dose was administered 3 times. The value obtained by dividing the average of the length A of the major axis and the length B of the minor axis by 2 was used as the radius R of the raised rash, and a logarithmic fitting curve was calculated using the spreadsheet software "Excel" manufactured by Microsoft. The results are shown in Figure 12 . The details of the puncture device are described later.

[0068] In the injection needle 1, in order to make it difficult to suppress the skin swelling due to the second protrusion 12, a predetermined interval is preferably provided between the first protrusion 11 and the second protrusion 12. By providing a predetermined interval between the first protrusion 11 and the second protrusion 12, when injecting the medicament L into the skin S using the injection needle 1, room for skin swelling can be ensured around the first protrusion 11, more specifically, between the first protrusion 11 and the second protrusion 12. Thus, it is not easy to suppress the skin swelling due to the second protrusion 12, and the liquid can be injected efficiently.

[0069] From the viewpoint of ensuring the above-mentioned predetermined interval between the first protrusion 11 and the second protrusion 12, the above distance D1 is preferably 2.0 mm or more.

[0070] For example, as Figure 12 shown, when injecting the medicament into the skin S using the injection needle 1, even with a small injection volume, a raised rash is rapidly formed. Therefore, by setting the above distance D1 to 2.0 mm or more, it is not easy for the second protrusion 12 to hinder the formation of the initial raised rash 9, and the injectability of the liquid can be made good.

[0071] From the viewpoint of suppressing the reduction in the injectability of the liquid due to hindering the swelling of the raised rash 9, the above distance D1 is preferably at least one-half, more preferably at least two-thirds, and further preferably greater than the raised rash radius R of the raised rash 9 formed when injecting the medicament L into the skin S using the injection needle 1. The raised rash radius R mentioned here can be calculated by the following formula (1). In formula (1), V is the volume of the liquid injected into the skin S using the injection needle 1. The injected liquid is the liquid used in the above <Relationship between the liquid volume and the radius of the raised rash>. In addition, in formula (1), ln represents the natural logarithm.

[0072] R = 0.5406ln(V) + 0.9483……(1)

[0073] The reason why the above distance D1 is the above ratio or more, particularly preferably greater than the raised rash radius R, with respect to the raised rash radius R calculated by the following formula (1) will be described. For example, when injecting the medicament L into the skin S using an injection needle 1 having only one first protrusion 11, the first protrusion 11 piercing the skin S is located at the center of the raised rash 9. Therefore, by making the above distance D1 greater than the raised rash radius R of the raised rash 9, the second protrusion 12 is not likely to hinder the formation of the raised rash during medicament injection, and thus it is possible to effectively prevent the second protrusion 12 from suppressing the injection of the medicament.

[0074] In addition, when injecting the medicament L into the skin S using the injection needle 1 having a plurality of first protrusions 11, raised rashes are formed centering on each of the first protrusions 11 that pierce the skin S. Therefore, for each of the first protrusions 11, by making the above distance D1 larger than the raised rash radius R of the raised rashes formed by the respective first protrusions 11, the second protrusions 12 are less likely to obstruct the formation of the raised rashes during the injection of the medicament, and thus the injection of the medicament can be effectively prevented from being inhibited.

[0075] From the viewpoint of more significantly exerting the effect of effectively preventing the second protrusions 12 from inhibiting the skin from bulging, the above distance D1 is preferably 2.05 mm or more, more preferably 2.1 mm or more. More specifically, when the volume V of the liquid injected into the skin S using the injection needle 1 is less than 10 μL, the above distance D1 is preferably 2.0 mm or more, more preferably 2.1 mm or more. In addition, when the above liquid volume V is 10 μL or more, the above distance D1 is preferably 2.1 mm or more, more preferably 2.2 mm or more.

[0076] From the viewpoints of making the injection needle 1 smaller to improve the operability or making the inhibition of skin extension caused by the stimulating protrusions 32 more effective, the above distance D1 is preferably 10 mm or less, more preferably 7 mm or less, and further preferably 4 mm or less.

[0077] By piercing the skin with the stimulating protrusions 32, the immune induction effect can be promoted. In order to significantly exert this effect, it is preferable that the liquid injection point of the injection needle 1, that is, the portion pierced by the first protrusions 11 and the portion pierced by the stimulating protrusions 32 are close to each other. Specifically, it is preferable that the upper limit value of the above distance D1 is within the above range.

[0078] Here, the distance between the first protrusion 11 and the second protrusion 12 refers to the distance between the vertex of the first protrusion 11 and the vertex of the second protrusion 12. When the second protrusion 12 is the control protrusion 33, the distance between the first protrusion 11 and the second protrusion 12 refers to the distance between the vertex of the first protrusion 11 and the center of the control protrusion 33 when viewed from above.

[0079] As Figure 1 In the case where the first region R1 contains a plurality of first protrusions 11 as shown in the example, it is preferable that, for each of the plurality of first protrusions 11, the above distance D1 is within the above range.

[0080] The injection needle 1 preferably has a protrusion non - existence region R3 that does not include the first protrusions 11 and the second protrusions 12 between the first region R1 and the second region R2. Specific examples thereof are shown in (a) to (d) of Figure 4 and Figure 6 below.

[0081] The protrusion non-existence region R3 is a region where the above distance D1 is within the above range for each of the first protrusions 11 included in the first region R1. The protrusion non-existence region R3 is a region having a prescribed width. In Figure 4 the example shown, the width of the protrusion non-existence region R3 is the same as the above distance D1. The protrusion non-existence region R3 is preferably a region that does not include at least the front ends of the first protrusion 11 and the second protrusion. The first protrusion 11 and the second protrusion 12 may stand up steeply from the sheet base portion 2 or may stand up gently. For example, in the case where the first protrusion 11 or the second protrusion 12 stands up gently from the sheet base portion 2, the protrusion non-existence region R3 may include the base end portions of the first protrusion 11 or the second protrusion 12.

[0082] In the case where the first protrusion 11 or the second protrusion 12 stands up gently from the sheet base portion 2, the distance between the first protrusion 11 and the second protrusion 12 at the height position of 80% of the height H1 of the first protrusion 11 may be used as the width of the protrusion non-existence region R3. In the case where the first protrusion 11 or the second protrusion 12 stands up steeply from the sheet base portion 2, the distance between the base end portions of the first protrusion 11 and the second protrusion 12 may be used as the width of the protrusion non-existence region R3.

[0083] Preferably, the protrusion non-existence region R3 surrounds the first region R1 when looking down at the sheet base portion 2. In addition, preferably, the protrusion non-existence region R3 has a prescribed width and continuously surrounds the periphery of the first region R1. Specific examples thereof are shown in Figure 4 、 Figure 6 (a) to (c) of.

[0084] The protrusion non-existence region R3 may also sandwich the first region R1 when looking down at the sheet base portion 2. Specific examples thereof are shown in Figure 6 (d) of.

[0085] Since the injection needle 1 has the protrusion non-existence region R3, when injecting a liquid into the skin using the injection needle 1, the skin can bulge without limitation, and thus the liquid can be injected more effectively.

[0086] The shape of the protrusion non-existence region R3 when looking down is not particularly limited. However, since the raised rash is formed in a circular shape, it is preferably annular, and particularly preferably a circular annulus. For example, it may be a circular annulus (refer to Figure 4 、 Figure 6 (a) of), a rectangular annulus (refer to Figure 6 (b) of), a triangular annulus (refer to Figure 6 (c) of), etc.

[0087] In the injection needle 1, the second protrusion 12 preferably has a stimulating protrusion 32 and a control protrusion 33. By having the stimulating protrusion 32 on the second protrusion 12, when the injection needle 1 is pressed against the skin and the first protrusion 11 penetrates the skin from the front end side, the stimulating protrusion 32 also penetrates the skin. By the stimulating protrusion 32 penetrating the skin, the extension of the skin can be prevented, and thus the puncture performance can be improved. In addition, by the stimulating protrusion 32 penetrating the skin, the stimulating protrusion 32 stimulates the skin to bring about a blood flow promoting effect, and can also promote the immune induction effect. Therefore, based on the injection needle 1 having such a structure, it is possible to easily inject a liquid into the skin through the first protrusion 11, and it is possible to promote blood flow and the immune induction effect through the stimulating protrusion 32.

[0088] The presence or absence of the blood flow promoting effect can be judged by various known methods. For example, it can be judged by whether a flare reaction occurs on the skin, or by visualizing the blood flow distribution with a laser blood flowmeter.

[0089] By having the control protrusion 33 on the second protrusion 12, when the first protrusion 11 and the stimulating protrusion 32 penetrate the skin from the front end side, the puncture depth control portion 40 of the control protrusion 33 contacts the surface of the skin. Thereby, the penetration of the first protrusion 11 and the stimulating protrusion 32 stops, and it is possible to prevent the first protrusion 11 and the stimulating protrusion 32 from penetrating deeper into the skin. That is, the puncture depth control portion 40 functions as a limiter for limiting the penetration depth of the first protrusion 11 and the stimulating protrusion 32.

[0090] That is, by being able to control the penetration depth of the first protrusion 11 and the stimulating protrusion 32 into the skin, the injection needle 1 can administer the medicine intradermally at an arbitrary depth of the skin and can effectively promote blood flow. Therefore, by adjusting the penetration depth of the first protrusion 11 according to the type of medicine, etc., the effect of the medicine can be maximized. In addition, by adjusting the penetration depth of the stimulating protrusion 32 according to the degree of the target blood flow promoting effect, the blood flow promoting effect can be effectively generated.

[0091] In the injection needle 1, it is preferable that the height of the first protrusion 11 is higher than the height of the second protrusion 12. By forming such a structure, after the first protrusion 11 penetrates the skin, the second protrusion 12 contacts the skin. Therefore, the penetration of the first protrusion into the skin can be efficiently performed, and the second protrusion 12 can prevent the skin from extending. After that, the operation of puncturing the first protrusion 11 to an arbitrary depth can be smoothly performed. Typically, the second protrusion 12 has a stimulating protrusion 32 and a control protrusion 33, and preferably the height of the first protrusion 11 is higher than the heights of the stimulating protrusion 32 and the control protrusion 33, respectively.

[0092] From the viewpoint of significantly reducing the pain associated with intradermal administration or reliably injecting a medicament from the first protrusion 11 into the skin S, the difference H1 - H3 between the protruding height H1 of the first protrusion 11 and the protruding height H3 of the control protrusion 33 is preferably 100 μm or more, more preferably 300 μm or more.

[0093] In addition, from the viewpoint of not overly damaging the skin, the above difference H1 - H3 is preferably 4995 μm or less, more preferably 3000 μm or less.

[0094] From the viewpoint of significantly reducing the pain associated with the blood flow promoting effect generated by the stimulating protrusion 32 or being able to sufficiently pierce the elastic skin with the stimulating protrusion, the protruding height H2 of the stimulating protrusion 32 is preferably equal to or greater than the protruding height H3 of the control protrusion 33, that is, H2 ≥ H3, and more preferably H2 > H3.

[0095] From the same viewpoint, the difference H2 - H3 between the protruding height H2 of the stimulating protrusion 32 and the protruding height H3 of the control protrusion 33 is preferably 0 μm or more, more preferably 100 μm or more, and further preferably 400 μm or more.

[0096] In addition, from the viewpoint of not overly damaging the skin, the above difference H2 - H3 is preferably 4995 μm or less, more preferably 3000 μm or less.

[0097] From the viewpoint of more reliably exerting the blood flow promoting effect or reliably puncturing the first protrusion 11 and efficiently performing injection, it is preferable that the height of the first protrusion 11 is higher than the height of the stimulating protrusion 32. More specifically, the difference H1 - H2 between the protruding height H1 of the first protrusion 11 and the protruding height H2 of the stimulating protrusion 32 is preferably 10 μm or more, more preferably 100 μm or more.

[0098] In addition, from the viewpoint of easily balancing the ease of liquid injection and the blood flow promoting effect, the above difference H1 - H2 is preferably 4995 μm or less, more preferably 3000 μm or less.

[0099] From the viewpoint of being able to smoothly pierce even when the skin deforms when the first protrusion 11 is pressed against the skin, having good puncture performance, and reliably injecting the medicament into the skin S, the protruding height H1 of the first protrusion 11 is preferably 105 μm or more, more preferably 150 μm or more.

[0100] In addition, from the viewpoint of low invasiveness, the protruding height H1 of the first protrusion 11 is preferably 5000 μm or less, more preferably 4000 μm or less, and further preferably 3000 μm or less.

[0101] From the viewpoint of applying a stimulus to the skin by pressing against the skin to promote blood flow, the protruding height H2 of the stimulating protrusions 32 is preferably 5 μm or more, more preferably 20 μm or more.

[0102] On the other hand, from the viewpoint of low invasiveness, the protruding height H2 of the stimulating protrusions 32 is preferably 5000 μm or less, more preferably 4000 μm or less, and further preferably 3000 μm or less.

[0103] Regarding the protruding height H3 of the control protrusions 33, from the viewpoint of minimizing skin trauma or improving puncture performance by increasing the distance between the substrate and the skin, it is preferably 5 μm or more, more preferably 10 μm or more.

[0104] On the other hand, from the viewpoint of improving the puncture performance of the first protrusions 11, the protruding height H3 of the control protrusions is preferably 4000 μm or less, more preferably 3000 μm or less, and further preferably 2000 μm or less.

[0105] In Figure 1 in the injection needle 1 shown, when envisioning the smallest imaginary circle M1 (see Figure 4 ) that includes the centers of all the first protrusions 11 contained in the first region R1, it is preferable that the radius D2 of this imaginary circle M1 (see Figure 4 ) is smaller than the shortest distance D1 (see Figure 4 ) among the distances between the first protrusions 11 and the second protrusions 12. When the center of the first protrusion 11 is located on the circumference of the above-mentioned imaginary circle M1, the center of this first protrusion 11 is included in this imaginary circle M1. By configuring the relationship between the above-mentioned radius D and the above-mentioned distance D1 as described above, when injecting a liquid into the skin using the injection needle 1, it is less likely to obstruct the formation of the raised rash 9, and the liquid can be injected more effectively. From the viewpoint of more significantly demonstrating this effect, the ratio D1 / D2 of the above-mentioned radius D2 to the above-mentioned distance D1 is preferably 1.0 or more, more preferably 1.5 or more.

[0106] On the other hand, from the viewpoint of dispersing the liquid injection site with respect to the formed raised rash or reducing the size of the injection needle 1, the above-mentioned ratio D1 / D2 is preferably 20 or less, more preferably 10 or less.

[0107] In the injection needle 1, it is preferable that the shortest distance D3 (see Figure 4 ) among the distances between the first protrusions 11 in the first region R1 is shorter than the above-mentioned distance D1. When injecting a liquid into the skin using the injection needle 1, it is more difficult to obstruct the formation of the raised rash 9, and the liquid can be injected more effectively. From the viewpoint of more significantly demonstrating this effect, the ratio D1 / D3 of the above-mentioned distance D3 to the above-mentioned distance D1 is preferably 1.0 or more, more preferably 1.5 or more.

[0108] In addition, from the viewpoints of the injection site for dispersing the liquid relative to the formed raised rash or reducing the injection needle 1, the above ratio D1 / D3 is preferably 20 or less, more preferably 10 or less.

[0109] In the injection needle 1, from the viewpoint of the balance between the ease of puncture and liquid injection and the blood flow promoting effect, the ratio of the number of the second protrusions 12 to the number of the first protrusions 11 (the number of the second protrusions 12 / the number of the first protrusions 11) is preferably 2.4 or more, more preferably 3.0 or more, and further preferably 3.5 or more.

[0110] In addition, from the viewpoint of low invasiveness, it is preferably 10 or less, more preferably 8 or less, and further preferably 6 or less.

[0111] In the injection needle 1, from the viewpoint of being able to effectively inject the liquid using the injection needle 1, the first region R1 preferably includes 2 or more, more preferably 3 or more, of the first protrusions 11.

[0112] In addition, from the viewpoint of being able to inject the liquid well from all the first protrusions 11, it preferably includes 20 or less, more preferably 15 or less, and further preferably 10 or less, of the first protrusions 11.

[0113] In the injection needle 1, the second region R2 may include the first protrusions 11, but preferably does not include the first protrusions 11 (refer to Figure 4 , Figure 6 ). Because the second region R2 does not include the first protrusions 11, only the first region R1 in the injection needle 1 becomes the region where the liquid can be injected. Therefore, the position of the raised rash can be limited to the first region, and the formation of the raised rash at other positions can be prevented from being hindered.

[0114] As the second protrusion 12, the injection needle 1 may have a composite second protrusion 52 in which a puncture depth control portion 40 is integrally formed around the stimulating protrusion 32. This example is shown in Figure 7 . In the example shown in Figure 7 , the puncture depth control portion 40 is integrally formed on the outer peripheral portion of the base side portion of the stimulating protrusion 32, thereby forming the composite second protrusion 52. More specifically, a diameter-expanded portion 41 is formed in the base side portion, and a stepped portion extending radially outward of the stimulating protrusion 32 is formed at the upper end portion of the diameter-expanded portion 41. This stepped portion becomes the puncture depth control portion 40.

[0115] When the first protrusion 11 and the composite second protrusion 52 are inserted into the skin from the front end side, the insertion of the first protrusion 11 and the composite second protrusion 52 stops by the contact of the puncture depth control part 40 with the surface of the skin, preventing the first protrusion 11 and the composite second protrusion 52 from being inserted deeper into the skin. In the composite second protrusion 52, the puncture depth control part 40 is integrally formed around the stimulating protrusion 32, so that it is possible to more reliably prevent the composite second protrusion 52 from being inserted deeper into the skin.

[0116] Next, the constituent material of the injection needle 1 will be described.

[0117] From the viewpoints of ensuring the operability of the material, the strength and workability of the injection needle, the hardness of the first protrusion 11 and the second protrusion 12, easy injection of liquid and improvement of the blood flow promoting effect, the injection needle 1 preferably contains a thermoplastic resin. The injection needle is more preferably formed of a base material sheet containing a thermoplastic resin.

[0118] As the thermoplastic resin, one or more selected from polyolefins, polyesters, polyamides, polyamideimides, polyetheretherketones, polyetherimides, polyvinyl chlorides, acrylic resins, polystyrene resins, etc. can be included.

[0119] As the polyolefin, one or more selected from polypropylene, polyethylene, etc. can be included.

[0120] As the polyester, one or more selected from polyethylene terephthalate, polyfatty acid ester, polylactic acid, polycaprolactone, polybutylene succinate, etc. can be included.

[0121] As the polyamide, one or more selected from nylon, etc. can be included.

[0122] From the viewpoint of biodegradability, it is preferable to contain a polyfatty acid ester.

[0123] Specifically, as the polyfatty acid ester, one or more selected from polylactic acid, polyglycolic acid can be included.

[0124] From the viewpoints of improving the formability and dimensional stability of the injection needle, the proportion of the thermoplastic resin contained in the injection needle 1 relative to the total mass of the injection needle 1 is preferably 50% or more, more preferably 70% or more, and further preferably 90% or more.

[0125] In addition, from the viewpoint of adding, for example, a functional agent to the injection needle to give various effects, the proportion of the mass of the thermoplastic resin is preferably 100% or less, more preferably 98% or less, and further preferably 96% or less.

[0126] Here, as various functional agents, antibacterial agents, fungicides, humectants, flow improvers, antistatic agents, colorants, etc. can be used.

[0127] The agent injected into the skin using the injection needle 1 can be appropriately selected according to the use purpose of the injection needle 1.

[0128] In addition to being used for intradermal administration of agents, the injection needle 1 can also be used for subcutaneous administration, etc. The agent injected into the skin using the injection needle 1 can be an intradermal administration type agent or a subcutaneous administration type agent. An intradermal administration type agent refers to an agent whose recommended administration method is intradermal administration. A subcutaneous administration type agent refers to an agent whose recommended administration method is subcutaneous administration. Based on the injection needle 1, intradermal administration of the agent can be easily performed. Therefore, the agent injected into the skin using the injection needle 1 is preferably an intradermal administration type agent, and more preferably an intradermal administration type vaccine agent. Especially when using an intradermal administration type vaccine agent, not only can the agent be reliably administered into the dermis, but also antigen recognition based on the immune system can be effectively enhanced compared to subcutaneous administration. Therefore, an improvement in the vaccine effect can be expected. The skin has the epidermis, dermis, and subcutaneous tissue in sequence from the body surface side, and relatively more immune cells exist in the dermis. Therefore, when performing intradermal administration of an intradermal administration type vaccine agent using the injection needle 1, intradermal administration in the dermis is preferred from the viewpoint of improving the vaccine effect.

[0129] The agent can contain, for example, one or more selected from vaccines for infectious diseases such as hepatitis A, hepatitis B, hepatitis C, influenza, COVID-19, tuberculosis, rabies, poliomyelitis, chickenpox, rubella, measles, tetanus, herpes zoster, etc.; vaccines for treating chronic hepatitis B, tuberculosis, rabies, malignant neoplasms, herpes zoster, etc.; analgesics for cancer patients; insulin; biological agents; gene therapy drugs; injections and skin-applicable preparations, etc.

[0130] The first protrusion 11 of the injection needle 1 punctures the skin. Therefore, in addition to being used for existing pharmacologically active substances for transdermal administration, the injection needle 1 can also be applied to pharmacologically active substances that require subcutaneous injection.

[0131] The skin S into which the agent L is injected by the injection needle 1 can be human skin or the skin of an animal other than a human.

[0132] In the present invention, an injection device including an injection needle connected to a drug supply device capable of filling the agent is included. As the injection needle of the injection device of the present invention, the above-described injection needle 1 of the present invention can be used. As the drug supply device, for example, a syringe, a tube, an electric injector, etc. can be used. The drug supply device can also have a drug storage portion pre-filled with the agent.

[0133] In the injection device according to the present invention, when injecting a medicament, it is not easy to hinder the formation of the raised rash 9, so that the medicament can be injected efficiently. In addition, the syringe of the present invention can reliably administer the medicament intradermally. Therefore, by using a medicament supply device filled with an intradermal administration type medicament as the medicament supply device, the effect of the intradermal administration type medicament can be further improved.

[0134] The present invention includes a kit, which includes an injection needle, a medicament supply device capable of filling a medicament, and a medicament. As the injection needle included in the kit of the present invention, the above-mentioned injection needle 1 of the present invention can be used. As the medicament supply device, the same medicament supply device as the medicament supply device in the above-mentioned injection device of the present invention can be used. As the medicament, the same medicament as the medicament used in the above-mentioned injection needle 1 of the present invention can be used. This kit may include a puncture device having a structure capable of imparting a speed to the above-mentioned syringe in a direction perpendicular to the administration site. The puncture device is a tool for puncturing the skin S with the injection needle and has a structure such as a spring as a structure for imparting a speed for puncturing the skin with the injection needle. In addition, the "speed" is the speed at which the first protrusion 11 of the injection needle 1 punctures the skin.

[0135] In the kit according to the present invention, when injecting a medicament, it is not easy to hinder the formation of the raised rash 9, so that the medicament can be injected efficiently.

[0136] The puncture device has, for example: a holding part for holding the injection needle 1; a guiding mechanism for restricting the moving direction of the injection needle 1 so that the first protrusion 11 of the injection needle 1 pierces the skin substantially perpendicularly; and a driving mechanism for moving the injection needle 1 along the guiding mechanism. The above-mentioned driving mechanism preferably has a driving unit composed of a spring or the like, which moves the injection needle 1 while controlling the puncture speed of the first protrusion 11 of the injection needle 1 to a specified speed. The driving mechanism is preferably configured to be able to manually operate the driving unit.

[0137] The holding part is, for example, a part of the adapter member capable of connecting the injection needle 1 and the medicament supply device and capable of mounting the injection needle 1. The holding part can be formed, for example, at one end of the adapter member. In a state where the injection needle 1 and the medicament supply device are connected via the adapter member, it is preferable that the medicament can be supplied from the medicament supply device to the first protrusion 11 of the injection needle 1. The method of mounting the injection needle 1 on the holding part is not particularly limited. For example, any method such as fitting, screwing, welding, and bonding can be used. In addition, the holding part and the injection needle 1 may each have engaging parts that engage with each other, and the injection needle 1 is mounted on the holding part by engaging the engaging parts. The other end of the adapter member is preferably capable of mounting the medicament supply device. For example, it is preferable that the other end of the adapter member is formed to be able to insert the front end opening of the syringe.

[0138] The guiding mechanism includes, for example: a guiding hole provided in the side wall of the cylindrical main body portion constituting the main body of the puncturing device; and an injection instrument holder having a guiding protrusion inserted into the guiding hole. The guiding hole has an opening shape extending along the axial direction of the main body portion. The injection instrument holder holds an injection instrument formed by connecting an injection needle 1 and a medicine supply device via an adapter member. By inserting the guiding protrusion of the injection instrument holder into the guiding hole, the moving direction of the injection instrument holder is restricted to the axial direction of the main body portion. The injection instrument holder is disposed inside the main body portion.

[0139] The driving unit of the driving mechanism is preferably configured to move the injection instrument holder. In addition, when the driving unit is a spring, the puncturing device preferably has a stopper mechanism for maintaining the contracted state of the spring. Preferably, the stopper mechanism maintains the contracted state of the spring by fixing the position of the guiding protrusion.

[0140] A method of injecting a medicine into the skin using the puncturing device will be described.

[0141] First, a syringe as a medicine supply device is filled with a medicine. Specifically, with the front end opening portion of the syringe immersed in the medicine, the plunger inserted in the syringe is pulled up to suck the medicine into the syringe. An injection needle 1 is attached to the filled syringe via an adapter member to form an injection instrument. The plunger of the syringe is pressed to fill the first protrusion 11 of the injection needle 1 with the medicine. The injection instrument is held by the injection instrument holder, and the injection instrument is attached to the puncturing device. The guiding protrusion of the injection instrument holder is pushed upward along the guiding hole to contract the spring of the driving mechanism that applies a force to the injection instrument holder. The guiding protrusion is fixed by the stopper mechanism to maintain the contracted state of the spring (hereinafter, this state will also be referred to as the "standby state"). The first protrusion 11 of the injection needle 1 in the puncturing device in the standby state is brought close to the skin as the medicine administration target. At this time, it is preferable that the axial direction of the main body portion of the puncturing device is perpendicular to the skin. Then, the fixing of the guiding protrusion is released. In this way, the injection needle 1 is forced against the skin, and the first protrusion 11 punctures the skin. After that, the plunger of the syringe is pressed to inject the medicine into the skin.

[0142] The present invention has been described based on its preferred embodiments, but the present invention is not limited to the above embodiments and can be appropriately changed.

[0143] For example, in Figure 3 the example shown, the second protrusion 12 is solid, but the second protrusion 12 may also be hollow. In addition, in Figure 7In the example shown, the composite second protrusion 52 is solid, but the composite second protrusion 52 may also be hollow. In the injection needle 1, the protrusions other than the first protrusion 11 are preferably solid. Thereby, it is possible to prevent the liquid to be discharged from the opening 11a of the first protrusion 11 from accumulating inside other protrusions, and thus it is possible to efficiently inject the liquid.

[0144] In Figure 1 the example shown, the injection needle 1 has an overall flat sheet-like shape, but the overall shape of the injection needle 1 is not limited to this. The injection needle 1 may also be integrally formed with the adapter member. For example, the first protrusion 11 and the second protrusion 12 may protrude from one surface side of a plate-like member, and a cylindrical portion that functions as an adapter member by bonding or the like or by integral molding may be provided at the peripheral portion on the other surface side. In this case, the above-mentioned plate-like portion is the sheet base portion 2.

[0145] Example

[0146] Hereinafter, the present invention will be described more specifically by way of examples, but the present invention is not limited to these examples.

[0147] 〔Example 1〕

[0148] Manufacture an injection needle having the same structure and the same protrusion configuration as the Figure 1 and Figure 2 shown injection needle 1. The dimensions of each protrusion of the injection needle, the shortest distance D1 between the first protrusion and the second protrusion, the radius D2 of the smallest imaginary circle including the centers of all the first protrusions included in the first region, the shortest distance D3 between the first protrusions in the first region, and the ratio of the mass of the thermoplastic resin to the total mass of the injection needle are shown in Table 1. In the injection needle of Example 1, the top view shape of the protrusion non-existence region is a circular ring shape surrounding the first region. The injection needle is formed by performing protrusion formation processing using a processing needle applying ultrasonic vibration on a base material sheet composed of 100% polylactic acid as a thermoplastic resin.

[0149] [Table 1]

[0150]

[0151] 〔Example 2〕

[0152] Manufacture an injection needle having the same structure as the Figure 1 shown injection needle 1A and the same configuration as Figure 6 (d) thereof. Except that each element is as shown in Table 1, it is the same as Example 1. Regarding the injection needle of Example 2, the top view shape of the protrusion non-existence region is rectangular, and the protrusion non-existence region sandwiches the first region.

[0153] [Comparative Example 1]

[0154] An injection needle having a first protrusion 11, a stimulating protrusion 32, and a control protrusion 33 was manufactured (refer to Figure 9 (a) of Figure 9 . Except that each element was as shown in Table 1 and the protrusions 11, 32, and 33 were arranged as shown in

[0155] (a) thereof, it was the same as Example 1. The injection needle of Comparative Example 1 did not have a protrusion non - existent region.

[0156] An injection needle having only the first protrusion 11 was manufactured (refer to Figure 9 (b) of

[0157] [Comparative Example 2]

[0158] Using the injection needles of Example 1 and 2 and Comparative Examples 1 and 2, the liquid medicine was administered to the skin of Göttingen minipigs by the following method.

[0159] The excised skin of Göttingen minipigs (male, 6 - week - old, ventral part; Oriental Yeast Co., Ltd.) stored at - 20°C was transferred from the day before the experiment to a refrigerator (4°C) and thawed. The excised skin was placed on 5 - 7 sheets of wiping paper towels, shaved using a razor, and used for drug administration after wiping the surface with an alcohol swab.

[0160] Rhodamine B powder (Sigma - Aldrich) was adjusted to 0.5 mg / mL with ultrapure water and filled into a microsyringe (Agilent). The microsyringe was set in the puncture device, and the injection needles of Example 1 and 2 and Comparative Examples 1 and 2 were respectively installed, and air was exhausted. The liquid volume in the microsyringe was set to 100 μL, and the excess liquid attached to the injection needle was absorbed and removed by a wiping paper. The protrusion of the injection needle was perpendicularly punctured into the puncture target, and 100 μL of an aqueous rhodamine B solution was injected.

[0161] After the liquid medicine was administered to the skin of Göttingen minipigs by the method described in the above [Administration of Liquid Medicine], the puncture property and the drug administration property of the injection needles of Example 1 and 2 and Comparative Examples 1 and 2 were respectively evaluated according to the following evaluation criteria. The results are shown in Table 1.

[0162] [Evaluation Criteria for Puncture Property]

[0163] 〇: Satisfies both of the following (1) and (2).

[0164] (1) When puncturing the first protrusion, it is possible to puncture to a depth at which liquid injection can be performed.

[0165] (2) When puncturing the first protrusion, it will not penetrate too deeply, and it is possible to puncture to a depth at which a raised rash is formed during liquid medicine injection.

[0166] ×: Does not meet either or both of the above (1) and (2).

[0167] [Evaluation criteria for drug delivery]

[0168] 〇: Meets both of the following (1) and (2).

[0169] (1) Immediately after the administration of the liquid medicine, it is possible to visually confirm the formation of a raised rash, and the formation of the raised rash is not hindered by the second protrusion.

[0170] (2) Wipe the skin surface of the administration site and the surface of the injection needle after administration with a tissue paper whose weight has been measured in advance. Before and after wiping, the weight change of this tissue paper is 5 mg or less.

[0171] ×: Does not meet either or both of the above (1) and (2).

[0172] As shown in Table 1, it can be seen that the puncture performance and drug delivery performance of the injection needles of Examples 1 and 2 are both evaluated as "〇", it is easy to puncture the first protrusion, and it is not easy to hinder the formation of a raised rash during liquid injection. As shown in Table 1, the puncture performance of the injection needle of Comparative Example 1 is evaluated as "〇", on the other hand, the drug delivery performance is evaluated as "×". As shown in Table 1, the puncture performance and drug delivery performance of the injection needle of Comparative Example 2 are both evaluated as "×".

[0173] Especially regarding the puncture performance, when the injection needle of Comparative Example 2 punctures the first protrusion, the above-mentioned cut skin will extend, it is difficult to properly puncture the first protrusion, or it penetrates too deeply, and it is difficult to inject the liquid medicine to the specified depth. Also in terms of drug delivery performance, since the first protrusion cannot be punctured and the liquid medicine leaks, or the first protrusion penetrates too deeply and the liquid medicine cannot be injected to the specified depth, a raised rash is not formed. Therefore, it can be seen that the injection needle of the present invention is not likely to inhibit the raising of the skin when injecting a liquid, and can efficiently inject the liquid.

[0174] Industrial applicability

[0175] According to the present invention, when injecting a liquid into the skin using an injection needle, it is not easy to inhibit the raising of the skin due to the injected liquid, and the liquid can be efficiently injected.

Claims

1. An injection needle, characterized in that: it has fine first protrusions and second protrusions protruding from a piece base; the first protrusion is conical in shape and has an opening at the front end; the second protrusion does not have an opening at the front end; when viewed from above, it has a first region including one or two or more first protrusions, and a second region including two or more second protrusions and sandwiching or surrounding the first region; the shortest distance D1 among the distances between the first protrusion and the second protrusion is 2.0 mm or more and 10 mm or less.

2. The injection needle according to claim 1, characterized in that: the first region includes two or more first protrusions; when imagining the smallest imaginary circle including the center of all the first protrusions included in the first region, the radius D2 of the imaginary circle is smaller than the distance D1.

3. The injection needle according to claim 1 or 2, characterized in that: the first region includes two or more first protrusions; the shortest distance D3 among the distances between the first protrusions in the first region is shorter than the distance D1.

4. The injection needle according to any one of claims 1 to 3, characterized in that: the height of the first protrusion is higher than the height of the second protrusion.

5. The injection needle according to any one of claims 1 to 4, characterized in that: the second protrusion has: a conical stimulating protrusion; and a puncture depth control protrusion whose front end surface becomes a puncture depth control part.

6. The injection needle according to claim 5, characterized in that: the front end surface of the puncture depth control protrusion is flat or formed into a curved line convex in the protruding direction of the puncture depth control protrusion.

7. The injection needle according to claim 5 or 6, characterized in that: the height of the stimulating protrusion is higher than the height of the puncture depth control protrusion.

8. The injection needle according to any one of claims 5 to 7, characterized in that: the height of the first protrusion is higher than the heights of the stimulating protrusion and the puncture depth control protrusion respectively.

9. The injection needle according to any one of claims 5 to 8, characterized in that: the difference H1 - H3 between the protruding height H1 of the first protrusion and the protruding height H3 of the puncture depth control protrusion is 100 μm or more and 4995 μm or less, preferably 300 μm or more and 3000 μm or less.

10. The injection needle according to any one of claims 5 to 9, characterized in that: the difference H2 - H3 between the protruding height H2 of the stimulating protrusion and the protruding height H3 of the puncture depth control protrusion is 0 μm or more and 4995 μm or less, more preferably 100 μm or more and 3000 μm or less, and further preferably 400 μm or more and 3000 μm or less.

11. The injection needle according to any one of claims 5 to 10, characterized in that: the difference H1 - H2 between the protruding height H1 of the first protrusion and the protruding height H2 of the stimulating protrusion is 10 μm or more and 4995 μm or less, preferably 100 μm or more and 3000 μm or less.

12. The injection needle according to any one of claims 5 to 11, characterized in that: The protruding height H1 of the first protrusion is 105 μm or more and 5000 μm or less, preferably 150 μm or more and 4000 μm or less, more preferably 150 μm or more and 3000 μm or less.

13. The injection needle according to any one of claims 5 to 12, characterized in that: The protruding height H2 of the stimulating protrusion is 5 μm or more and 5000 μm or less, preferably 20 μm or more and 4000 μm or less, more preferably 150 μm or more and 3000 μm or less.

14. The injection needle according to any one of claims 5 to 13, characterized in that: The protruding height H3 of the puncture depth control protrusion is 5 μm or more and 4000 μm or less, preferably 10 μm or more and 3000 μm or less, more preferably 10 μm or more and 2000 μm or less.

15. The injection needle according to any one of claims 1 to 14, characterized in that: The ratio D1 / D2 of the distance D1 to the radius D2 of the smallest imaginary circle containing the centers of all the first protrusions in the first region is 1.0 or more and 20 or less, preferably 1.5 or more and 10 or less, and / or, The ratio D1 / D3 of the distance D1 to the shortest distance D3 among the distances between the first protrusions in the first region is 1.0 or more and 20 or less, preferably 1.5 or more and 10 or less.

16. The injection needle according to any one of claims 1 to 15, characterized in that: The ratio D1 / D2 of the distance D1 to the radius D2 of the smallest imaginary circle containing the centers of all the first protrusions in the first region is 1.0 or more and 20 or less, preferably 1.5 or more and 10 or less.

17. The injection needle according to any one of claims 1 to 16, characterized in that: The ratio D1 / D3 of the distance D1 to the shortest distance D3 among the distances between the first protrusions in the first region is 1.0 or more and 20 or less, preferably 1.5 or more and 10 or less.

18. The injection needle according to any one of claims 1 to 17, characterized in that: The first region contains 2 or more and 20 or less first protrusions, preferably 3 or more and 20 or less first protrusions, more preferably 3 or more and 15 or less first protrusions.

19. The injection needle according to any one of claims 1 to 18, characterized in that: The ratio of the number of the second protrusions to the number of the first protrusions is 2.4 or more and 10 or less, preferably 3.0 or more and 8 or less, more preferably 3.5 or more and 6 or less.

20. The injection needle according to any one of claims 1 to 19, characterized in that: The second region does not contain the first protrusions.

21. The injection needle according to any one of claims 1 to 20, characterized in that: There is a protrusion non-existence region between the first region and the second region that does not contain the first protrusions and the second protrusions.

22. The injection needle according to claim 21, characterized in that: When looking down at the sheet base, the protrusion non-existence region sandwiches or surrounds the first region.

23. The injection needle according to claim 21 or 22, characterized in that: The protrusion non-existence region has a predetermined width and continuously surrounds the periphery of the first region.

24. The injection needle according to any one of claims 21 to 23, wherein: The top view shape of the protrusion non-existence region is annular, preferably a circular ring.

25. The injection needle according to any one of claims 1 to 24, wherein: The first region includes a plurality of first protrusions. The plurality of first protrusions included in the first region are arranged in such a manner that a virtual line connecting the centers of the first protrusions is annular in a top view.

26. The injection needle according to claim 25, wherein: No first protrusion is arranged within the region surrounded by the virtual line.

27. The injection needle according to any one of claims 1 to 26, wherein: The second protrusions included in the second region are arranged in such a manner that a virtual line connecting the centers of the respective second protrusions is annular in a top view.

28. The injection needle according to any one of claims 1 to 27, wherein: The distance D1 is 2.05 mm or more and 10 mm or less, preferably 2.1 mm or more and 7.0 mm or less, more preferably 2.1 mm or more and 4 mm or less.

29. The injection needle according to any one of claims 1 to 28, wherein: The injection needle contains a thermoplastic resin, and the proportion of the mass of the thermoplastic resin relative to the total mass of the injection needle is 50% or more and 100% or less, more preferably 70% or more and 98% or less, further preferably 90% or more and 96% or less.

30. The injection needle according to any one of claims 1 to 29, wherein: The injection needle is an injection needle for intradermal administration of a medicament.

31. An injection device, wherein: The injection needle according to any one of claims 1 to 29 and a medicament supply device capable of filling a medicament are connected.

32. A kit, characterized in that, Comprising: The injection needle according to any one of claims 1 to 29; A medicament supply device capable of filling a medicament; And A medicament.

33. A kit, characterized in that, Comprising: The injection needle according to any one of claims 1 to 29; A medicament supply device capable of filling a medicament; A medicament; And A puncture device capable of moving the injection needle toward the skin and causing the first protrusion of the injection needle to puncture the skin.

34. An injection device, wherein: The injection needle according to any one of claims 1 to 29 and a medicament supply device capable of filling a medicament are connected, wherein the medicament is one or more selected from vaccines for preventing infectious diseases such as hepatitis A, hepatitis B, hepatitis C, influenza, COVID-19, tuberculosis, rabies, poliomyelitis, varicella, rubella, measles, tetanus, herpes zoster; vaccines for treating chronic hepatitis B, tuberculosis, rabies, malignant neoplasms, herpes zoster, etc.; analgesics for cancer patients; insulin; biological agents; gene therapy drugs; injections and skin-applicable preparations.

35. A kit, characterized in that, Containing: The injection needle according to any one of claims 1 to 29; A medicament supply device capable of filling a medicament, wherein the medicament is one or more medicaments selected from vaccines for preventing infectious diseases such as hepatitis A, hepatitis B, hepatitis C, influenza, COVID-19, tuberculosis, rabies, poliomyelitis, chickenpox, rubella, measles, tetanus, herpes zoster; vaccines for treating chronic hepatitis B, tuberculosis, rabies, malignant neoplasms, herpes zoster, etc.; analgesics for cancer patients; insulin; biological agents; gene therapy drugs; injectable preparations and skin-applicable preparations; and the medicament.

36. An injection device, characterized in that: an injection needle and a medicament supply device capable of filling an intradermal administration type vaccine medicament are connected, wherein the injection needle has fine first protrusions and second protrusions protruding from a piece base, the first protrusion is in a conical shape and has an opening at the front end, the second protrusion does not have an opening at the front end, in a plan view, there is a first area including one or more first protrusions and a second area including two or more second protrusions that sandwich or surround the first area, the shortest distance D1 among the distances between the first protrusion and the second protrusion is 2.0 mm or more and 10 mm or less.

37. A puncture method, characterized in that: the injection needle according to any one of claims 1 to 29 and a medicament supply device capable of filling a medicament are connected, and a puncture device that moves the injection needle toward the skin and punctures the skin with the first protrusion of the injection needle is used, so that the first protrusion of the injection needle punctures the skin.

38. A medicament supply method, characterized in that: a medicament is administered into the skin using a kit, the kit including the injection needle according to any one of claims 1 to 29, a medicament supply device capable of filling a medicament, and a medicament, the medicament supply method uses a puncture device to move the injection needle toward the skin and punctures the skin with the first protrusion of the injection needle to supply the medicament.

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