Microneedle capable of realizing intradermal injection

Abstract

The invention discloses a microneedle capable of realizing intradermal injection, and relates to the field of medical instruments. The needle body creatively adopts a novel structural design, it can be ensured that the piercing tip has a tip outline facilitating piercing, the needle body has a high-strength needle body root support, and due to the fact that the second inwards-concave arc line is an inwards-concave arc, on the basis that the piercing tip and the needle body root support are reliably connected, the piercing tip and the needle body root support can be supported by the second inwards-concave arc line, and the piercing tip and the needle body root support can be supported by the second inwards-concave arc line. Compared with an existing micro-needle which adopts an external expansion arc structure only with an external convex arc, the micro-needle has the advantages that the width of the needle head can be reduced and the needle head can be sharpened on the premise of keeping the size of an injection pore channel unchanged and keeping the distance between the injection pore channel and the front edge unchanged; the pain feeling when the needle penetrates into the skin can be effectively relieved, and meanwhile the puncture effect is not affected; the needle head is narrowed, so that the wound becomes small; the needle body and needle head designed by the invention can meet the requirements of reducing pain and shrinking wounds clinically.

Description

Technical Field

[0001] The invention belongs to the field of medical devices and relates to injection technology, in particular to a new type of microneedle capable of achieving intradermal injection. Background Art

[0002] Microneedles are mostly used for subcutaneous injection, intradermal injection or liquid extraction, and are generally connected to a syringe for use. When used, the tip of the microneedle is tilted and inserted into the subcutaneous tissue, and then injection or extraction is performed.

[0003] As people's requirements for medical experience increase, minimally invasive microneedle injection and reducing the pain of microneedle injection are gaining more and more attention. However, the existing microneedles are limited by the conventional structure and needle strength requirements and cannot meet the clinical needs of reducing pain and shrinking wounds. Based on this, the present invention proposes a microneedle that can be used for subcutaneous injection or fluid extraction. Summary of the invention

[0004] The purpose of the present invention is to provide a new type of microneedle that can achieve intradermal injection. Through innovative needle design, the needle can be sharpened while ensuring needle strength and basic injection flow rate, so as to meet the clinical needs of reducing pain and shrinking wounds, and solve the problems existing in the above-mentioned prior art.

[0005] To achieve the above-mentioned purpose, the present invention provides the following scheme: The present invention provides a microneedle capable of intradermal injection, comprising a substrate and a needle body arranged on the substrate, the needle body comprising: a side profile surface protruding from the surface of the substrate, the side profile surface being a solid structure, the side profile surface comprising a front edge face and side faces symmetrically arranged on both sides of the front edge face, the front edge face and the side faces on both sides being smoothly transitioned and connected; an injection channel, which is opened on the solid structure in the side profile surface; an oblique plane, which is obliquely cut from the end of the side profile surface away from the substrate toward the substrate, and the intersection line of the oblique plane and the side profile surface is the needle blade of the needle body, the intersection line of the oblique plane and the injection channel is the contour line of the injection port of the needle body, and the intersection of the high end of the oblique plane and the front edge face is the insertion tip of the needle body; wherein, the needle blade on the surface of the substrate The projection contour line is a needle blade projection line, among which: the first convex arc line corresponds to the front edge elevation; the multiple arc lines correspond to the side elevations on both sides, the two multiple arc lines are the same, and are symmetrically arranged at both ends of the first convex arc line, wherein any multiple arc lines include a first concave arc line, a second convex arc line, a second concave arc line, a third convex arc line and an extension line which are sequentially tangently transitionally connected from the high end to the low end of the bevel plane, and the high end end of the first concave arc line is tangently transitionally connected to the end of the first convex arc line; wherein a reference point is set on the second concave arc line, and the portion of the multiple arc lines from the reference point to the first convex arc line shows a gradually inwardly contracting oblique trend toward the first convex arc line, and the portion of the multiple arc lines from the reference point to the end of the extension line shows a gradually outwardly expanding oblique trend toward the end of the extension line, or shows a trend of gradually expanding outwards and then keeping the inclination unchanged.

[0006] In some embodiments, on the bevel plane, the connecting line segment between the reference points of the two second concave arcs is set as the reference line segment, and a closed area is formed between the reference line segment and the first convex arc and the two multiple arcs, and the injection port contour line is located within the closed area.

[0007] In some implementations, in the needle blade projection line: the length of the reference line segment is 110 microns to 130 microns.

[0008] In some embodiments, the needle blade is on the projected contour line of the substrate surface: the radius of the first convex arc line is R1 = 30 microns ~ 40 microns, and its corresponding central angle γ is 60° ~ 65°; the radius of the second convex arc line is R2 = 118 microns ~ 122 microns, and the second convex arc line smoothly transitions to the first convex arc line through the first concave arc line; the radius of the second concave arc line is R3 = 150 microns ~ 160 microns, and the second concave arc line smoothly transitions to the extension line through the third convex arc line, and an outward-expanded shoulder is formed at the third convex arc line; the extension line is a vertical line, and the two extension lines are parallel; or, the extension line is an oblique straight line or an oblique arc line.

[0009] In some embodiments, an injection channel is opened in the needle body, and the projection contour line of the withdrawal port contour line on the surface of the substrate is a non-circular closed contour line, and the distance between any point on the non-circular closed contour line and the corresponding position of the needle blade projection line is d, 35 microns ≤ d ≤ 45 microns.

[0010] In some embodiments, the non-circular closed contour line is an elliptical contour line, and the major axis of the elliptical contour line coincides with the central symmetry line of the first convex arc line; In some embodiments, the non-circular closed contour line is a symmetrical polygonal contour line, and a rounded transition is set at any corner position of the symmetrical polygonal contour line, and the symmetry axis of the symmetrical polygonal contour line coincides with the central symmetry line of the first convex arc line.

[0011] In some embodiments, a distance between an intersection point of the central symmetry line and the first convex arc line and an intersection point of one end of the non-circular closed contour line facing the first convex arc line and the central symmetry line is 35 microns to 45 microns.

[0012] In some embodiments, the side profile surface as a whole protrudes perpendicularly from the substrate surface, and an angle α between the chamfered plane and the upright direction of the front edge vertical surface is 35.2°~36.2°.

[0013] In some embodiments, the side profile surface includes: an upright section, which protrudes vertically from the surface of the substrate; a contraction section, wherein the large end of the contraction section smoothly transitions to the end of the upright section away from the substrate, and the beveled plane is formed by beveling the small end of the contraction section toward the substrate, and the two ends of the boundary line between the contraction section and the upright section respectively intersect with the two third convex arcs of the beveled plane; the intersection line of the vertical section of the side profile surface and the beveled plane is a first oblique line; the central symmetry line of the first convex arc is located in the vertical section; the vertical section and the The intersection line of the front edge vertical surface in the contraction section is a second oblique line, and the angle β between the second oblique line and the first oblique line is 46°~61°; the intersection line of the vertical section and the front edge vertical surface in the upright section is a straight line, and the angle δ between the second oblique line and the straight line is 155°~170°; in the vertical section: the highest point of the projection line of the contour line of the injection port is at a vertical height of the hole height L1 from the surface of the substrate; the intersection point of the first oblique line and the second oblique line is at a vertical height of the needle height L2 from the surface of the substrate; and the value of L1 / L2 is 7 / 8~9 / 10.

[0014] In some embodiments, the leading edge elevation is arranged as a whole inclined toward the injection channel, and the two side elevations protrude vertically from the substrate surface as a whole; the intersection line of the vertical section of the side contour surface and the bevel plane is a first oblique line; the central symmetry line of the first outer convex arc line is located in the vertical section; the intersection line of the vertical section and the leading edge elevation is a second oblique line, and the angle β between the second oblique line and the first oblique line is 36°~39°; in the vertical section: the highest point of the projection line of the injection port contour line, the vertical height from the substrate surface is the hole height L1; the intersection of the first oblique line and the second oblique line, the vertical height from the substrate surface is the needle height L2; and the L1 / L2 value is 7 / 8~9 / 10.

[0015] Compared with the prior art, the present invention has achieved the following technical effects: the novel microneedle capable of achieving intradermal injection proposed by the present invention has a novel structural design for the needle body, which sets a reference point on the second concave arc line and limits the portion of the multi-arc line from the reference point to the first convex arc line to gradually shrink inwards towards the first convex arc line in an oblique trend, thereby ensuring that the insertion tip has a tip contour that is convenient for insertion, and the portion of the multi-arc line from the reference point to the tail of the extension line has a gradually expanding trend toward the tail of the extension line, in order to widen the main structure of the needle body and make the needle body have a high-strength support at the root of the needle body, and the second concave arc line is a concave circle. The arc can form an effective diameter reduction design at the root of the insertion tip on the basis of supporting the reliable connection between the insertion tip and the root of the needle body. Compared with the existing microneedle needle with an outward-expanding arc structure design with only an outward convex arc, the needle width can be reduced while keeping the injection channel size unchanged and the distance between the injection channel and the leading edge unchanged, so as to achieve needle sharpening, which can effectively reduce the pain when the needle pierces the skin without affecting the puncture effect; and the needle width is narrowed and the wound is smaller; the needle body needle designed by the present invention can meet the clinical needs of reducing pain and reducing wounds, and is suitable for various application scenarios such as intradermal injection and subcutaneous injection.

[0016] In some technical solutions disclosed in the present invention, the cross-sectional profile of the injection channel is designed as a non-circular closed contour line, which can maximize the cross-sectional area of ​​the non-circular closed contour line while ensuring the structural strength of the needle body, thereby increasing the injection flow or liquid extraction flow of each needle body.

[0017] In some technical solutions disclosed in the present invention, the side profile surface adopts a two-section type, and a contraction section is provided at the end away from the substrate, so that the vertical front edge elevation of the side profile surface is changed into a bent front edge elevation. This design makes the distance between the insertion tip and the injection channel closer, so that under the premise of ensuring the hole height remains unchanged, compared with the existing microneedle design, the needle height can be further reduced, and the ratio of the injection depth to the insertion depth of the microneedle can be increased, so that the needle tip insertion depth is shallower while maintaining the injection volume or the extraction volume unchanged, thereby further reducing the pain of microneedle insertion and the wound area, making it more in line with the painless operation characteristics of the microneedle.

[0018] In some technical solutions disclosed in the present invention, the front edge elevation of the side contour surface is set as an overall tilt. This design makes the distance between the insertion tip and the injection channel closer, so that under the premise of ensuring that the hole height remains unchanged, compared with the existing microneedle design, the needle height can be further reduced, and the ratio of the injection depth to the insertion depth of the microneedle can be increased. On the basis of keeping the injection volume or the extraction volume unchanged, the needle tip insertion depth is shallower, thereby further reducing the microneedle insertion pain and wound area, making it more in line with the painless operation characteristics of the microneedle. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 Schematic diagram of the front view of the microneedle disclosed in some embodiments (there is no groove on the periphery of the needle body).

[0021] Figure 2 for Figure 1 Schematic top view of .

[0022] Figure 3 for Figure 2 Schematic diagram of the enlarged structure at C in FIG.

[0023] Figure 4 for Figure 1 Schematic diagram of the projection outline of a single needle on the substrate surface.

[0024] Figure 5 for Figure 4 Schematic diagram of the enlarged structure of the needle tip of a single needle body.

[0025] Figure 6 for Figure 1 Schematic diagram of the AA cross-section structure.

[0026] Figure 7 It is a schematic front view of the microneedle disclosed in some embodiments (there is a groove on the periphery of the needle body).

[0027] Figure 8 for Figure 7 Schematic top view of .

[0028] Fig. 9 for Figure 8 Schematic diagram of the enlarged structure at B in FIG.

[0029] Fig.10 for Figure 7 Schematic diagram of the DD cross-section structure.

[0030] Fig.11 Schematic diagram of the three-dimensional structure of the microneedle body disclosed in some embodiments (there is no contraction section at the tip of the microneedle body).

[0031] Fig.12 It is a schematic diagram of the three-dimensional structure of a contraction section provided at the tip of a microneedle body disclosed in some embodiments.

[0032] Fig.13 In some embodiments, the disclosed Fig.11 Schematic diagram of the cross-section of the microneedle needle structure.

[0033] Fig.14 for Fig.13 Schematic diagram of needle height and hole height in the disclosed microneedle cross-sectional schematic diagram.

[0034] Fig.15 It is a schematic diagram of the cross-sectional structure of the microneedle body disclosed in some embodiments in which the front edge vertical surface is tilted as a whole.

[0035] In the figure, the reference numerals are: 100, microneedle; 1, substrate; 11, surface of substrate; 2, needle body; 21, side contour surface; 211, front edge elevation; 212, side elevation; 22, injection channel; 23, bevel plane; 24, needle blade; 241, first convex arc line; 242, first concave arc line; 243, second convex arc line; 244, second concave arc line; 245, third convex arc line; 246, extension line; 247, central symmetry line; 25, injection port contour line; 26, insertion tip; 27, reference line segment; 28, upright segment; 29, contraction segment; 210, boundary line; 213, first oblique line; 214, second oblique line; 215, straight line; 3, groove; 31, groove projection. DETAILED DESCRIPTION

[0036] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0037] The purpose of the present invention is to provide a new type of microneedle that can achieve intradermal injection. Through innovative needle design, the needle can be sharpened while ensuring the needle strength and basic injection flow rate, compared with the existing technology, so as to meet the clinical needs of reducing pain and shrinking wounds, and solve the problems existing in the existing technology.

[0038] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0039] Example 1 like Figure 1 to Figure 6As shown, this embodiment proposes a microneedle 100 capable of achieving intradermal injection, which includes a substrate 1 and a needle body 2 arranged on the substrate 1, and the needle body 2 includes a side profile surface 21 protruding from the surface of the substrate 1, an injection channel 22 and a beveled plane 23. Among them, the side profile surface 21 protruding from the surface 11 of the substrate is a solid structure inside the side profile surface 21, and the solid structure is generally designed as an integral whole with the substrate 1; the side profile surface 21 includes a front edge elevation 211 and side elevations 212 arranged symmetrically on both sides of the front edge elevation 211, and the front edge elevation 211 and the side elevations 212 on both sides are smoothly transitioned and connected, and together enclose the main structure of the needle body 2. The injection channel 22 is opened on the solid structure inside the side profile surface 21, and the injection channel 22 is arranged along the protruding direction of the side profile surface 21. The injection channel 22 simultaneously penetrates the substrate 1 and the above-mentioned solid structure, and the injection channel 22 is arranged close to the front edge elevation 211. The beveled plane 23 is formed by beveling the end of the side profile surface 21 away from the substrate 1 toward the substrate 1, and the intersection line of the beveled plane 23 and the side profile surface 21 is the needle blade 24 of the needle body 2, and the intersection line of the beveled plane 23 and the injection channel 22 is the injection port contour line 25 of the needle body 2. The injection port contour line 25 and the needle blade 24 are both exposed on the beveled plane 23, and the needle blade 24 is a part of the outer contour line of the beveled plane 23. The intersection of the high end of the beveled plane 23 and the aforementioned front edge vertical surface 211 is the insertion tip 26 of the needle body 2. When in use, after connecting the substrate 1 to the corresponding syringe, the insertion tip 26 of the needle body 2 is tilted downward and inserted into the subcutaneous tissue. After the insertion is in place, the syringe can be used to inject or extract liquid. In order to more clearly understand the innovative design of the needle body 2 of this solution, the structure is described with the projection contour line of the needle blade 24 on the surface 11 of the substrate as the focus, and a specific explanation is given: like Figure 2~Figure 5 As shown, the projection contour line of the needle blade 24 on the surface 11 of the substrate is defined as the needle blade projection line, in which: the first convex arc line 241 corresponds to the front edge elevation 211; the two side elevations 212 correspond to multiple arc lines, the two multiple arc lines are exactly the same, and are symmetrically arranged at both ends of the first convex arc line 241, wherein any multiple arc line includes a first concave arc line 242, a second convex arc line 243, a second concave arc line 244, a third convex arc line 245 and an extension line 246 which are sequentially tangently transitionally connected from the high end to the low end of the bevel plane 23, and the high end of the first concave arc line 242 is tangently transitionally connected to the end of the first convex arc line 241. In the above description, in order to clearly describe the structure, the projection contour line of the needle blade 24 is described in sections, but in fact, the front edge elevation 211 and the side elevations 212 on both sides are an integrated structure, and the projection contour line of the needle blade 24 is also an integrated structure.

[0040] It should be noted that in order to ensure that the needle blade 24 with multiple concave and convex arcs can smoothly penetrate the skin tissue, a reference point is set on the second concave arc 244 (not a structural component of the present invention), and the portion of the multiple arcs from the reference point to the first convex arc 241 shows a gradually inwardly contracting oblique trend toward the first convex arc 241, and the portion of the multiple arcs from the reference point to the tail of the extension line 246 shows a gradually outwardly expanding oblique trend toward the tail of the extension line 246, or shows a trend of gradually expanding outward first and then keeping the inclination unchanged. Figure 2~Figure 4 As shown, the multi-arc portion from the reference point to the tail of the extension line 246 gradually expands outwards towards the tail of the extension line 246, that is, the two extension lines 246 are symmetrical and gradually become a trumpet shape in the direction away from the insertion tip 26. The design of the extension line 246 is similar to the existing microneedle design, and the details are not repeated here.

[0041] The design of the needle body 2 is consistent with the contour trend of the needle blade 24 on the bevel plane 23 and the contour trend of the projection contour line of the needle blade 24 on the surface 11 of the substrate. The technical effect of the needle blade 24 can be effectively derived by designing the projection contour line of the needle blade 24 on the surface 11 of the substrate. Based on this, by setting a reference point on the second concave arc line 244 and limiting the portion of the multi-arc from the reference point to the first convex arc line 241 to gradually shrink inward toward the first convex arc line 241, it is to ensure that the insertion tip 26 has a tip contour that is easy to insert, and the portion of the multi-arc from the reference point to the tail of the extension line 246 has a gradually expanding trend toward the tail of the extension line 246, in order to widen the main structure of the needle body 2 so that it has a high-strength needle body root support, and the second concave arc line 244 is a concave arc, which can be used for the insertion tip 26. On the basis of supporting the reliable connection with the root of the needle body, an effective diameter reduction design is formed at the root of the insertion tip 26. Compared with the existing microneedle needle with an outward expansion arc structure design with only an outward convex arc, the needle width can be reduced to achieve needle sharpening while keeping the size of the injection channel 22 unchanged and the distance between the injection channel 22 and the leading edge unchanged. This design can effectively reduce the pain when the needle pierces the skin without affecting the puncture effect; the needle width is narrowed and the wound is smaller; the needle body and needle designed in this scheme can meet the clinical needs of reducing pain and reducing wounds.

[0042] At the same time, the needle blade 24 is connected by multiple concave arcs and multiple convex arcs, which can not only meet the design of the needle tip's sharp trend, but also adopt a smooth transition of the arc at the width change, which has the effect of reducing stress concentration and strengthening the needle tip's structural strength, so that the needle blade 24 of this solution can achieve the technical effect of reducing pain and reducing wounds, and can also maintain a high structural strength, thereby improving the performance and reliability of the microneedle 100. Moreover, the needle blade 24 adopts an arc design, which has the advantages of easy processing and low processing cost, breaking through the technical bottleneck that the current microneedles are limited by processing difficulty, structural strength, etc., and cannot improve painless and minimally invasive effects.

[0043] In some embodiments, on the bevel plane 23, a straight line connecting the reference points of the two second concave arcs 244 is set as a reference line segment 27, such as Figure 4 As shown, the reference line segment 27 and the first convex arc 241 and the two multiple arcs form a closed area, and the injection port contour line 25 is located in the closed area, so as to ensure Figure 4 After the needle tip above the reference line segment 27 shown penetrates the skin, the extraction port contour line 25 also enters the skin tissue as a whole, which can prevent the exit port of the injection channel 22 from being partially located outside the skin surface after the needle tip is inserted, causing a failure in extraction or leakage of liquid during injection. It should be noted that the reference line segment 27 is an auxiliary line used to help understand the setting position of the extraction port contour line 25, and is not a structural component of the needle body 2 in this solution.

[0044] In some embodiments, the needle blade 24 is preferably on the projection contour line of the surface 11 of the substrate: the length of the reference line segment 27 is 110 microns to 130 microns, and specifically 110 microns, 115 microns, 125 microns or 130 microns can be selected. As a further preferred solution, the reference points at both ends of the reference line segment 27 are generally located at the most concave point of the second concave arc 244, that is, the reference line segment 27 refers to the shortest distance between the two second concave arcs 244. At this time, the length of the reference line segment 27 can be used to characterize the width of the needle tip at the reduced diameter position, which has a significant size reduction compared to existing microneedles.

[0045] In some embodiments, Figure 5As shown, the preferred projection contour line of the needle blade 24 on the surface 11 of the substrate is: the radius of the first convex arc 241 is R1=30 microns to 40 microns, and the corresponding center angle γ is 60° to 65°. In a feasible solution, R1 can be set to 35 microns, and the center angle γ is 65°; the radius of the second convex arc 243 is R2=118 microns to 122 microns, and the second convex arc 243 smoothly transitions with the first convex arc 241 through the first concave arc 242 Connection; the radius of the second concave arc 244 is R3 = 150 microns ~ 160 microns, the second concave arc 244 is smoothly connected with the extension line 246 through the third convex arc 245, and an outward expansion shoulder is formed at the third convex arc 245, and the part above the outward expansion shoulder is the reduced diameter part of the needle. The existing microneedles do not have the above-mentioned outward expansion shoulder, but have a continuous convex structure. This further confirms that the present solution achieves a narrower needle width compared to the existing microneedles.

[0046] In some embodiments, the extension line 246 may be a vertical line, and the two extension lines 246 are parallel; or, the extension line 246 may be an oblique straight line or an oblique arc, such as Figure 3 and Figure 4 As shown in FIG. 2 , the extension line 246 is an arc with a gentle curvature, and the extension line 246 is outwardly expanding relative to the central symmetry line 247. It should be noted that the extension line 246 is set to Figure 3 and Figure 4 The arc line with a gentle curvature shown has the effect of making the contour of the needle blade 24 more rounded without affecting the use effect of the needle blade 24, thereby improving the structural strength of the needle blade 24.

[0047] In some embodiments, one, two or three injection channels 22 may be provided in the needle body 2 as required. In order to ensure the structural strength of the needle body 2, the present solution preferably provides an injection channel 22 in the needle body 2, and the projection contour line of the extraction port contour line 25 on the surface 11 of the substrate is a non-circular closed contour line, that is, the cross-sectional contour of the injection channel 22 is a non-circular closed contour line. In order to maximize the cross-sectional area of ​​the non-circular closed contour line on the basis of ensuring the structural strength of the needle body, and thereby increase the injection flow rate or extraction flow rate of each needle body 2, it is preferred that any point on the non-circular closed contour line and the distance between the corresponding position of the projection contour line of the needle blade 24 on the surface 11 of the substrate are d, and 35 microns ≤ d ≤ 45 microns. This design can be regarded as a design for thinning the wall thickness of the needle body.

[0048] In some embodiments, the non-circular closed contour is preferably an elliptical contour, and the major axis of the elliptical contour coincides with the central symmetry line 247 of the first convex arc 241. The non-circular closed contour adopts an elliptical contour, which has a technical effect of greater injection flow or liquid extraction flow compared to the circular cross-section injection hole in the traditional microneedle. Among them, the major axis length a of the elliptical contour line is preferably 100 microns to 115 microns, and correspondingly, the minor axis length of the elliptical contour line is 45 microns to 60 microns. Taking the major axis length a of the elliptical contour line as 100 microns and the minor axis length as 60 microns as an example, according to the liquid flow calculation formula Q=Sv, wherein Q represents the flow rate, S represents the pipe cross-sectional area, and v represents the liquid flow rate, the flow rate of the circular hole with an original aperture of 60 microns to 75 microns is Q=0.002826*V~0.004415625*V; and the flow rate of the elliptical hole with a major axis length a of 100 microns and a minor axis length of 60 microns is estimated to be 0.00471*V. Compared with the existing microneedle channel, the flow rate has been improved.

[0049] In some embodiments, Figure 6 and Fig.11 As shown, the side profile surface 21 as a whole vertically protrudes from the surface 11 of the substrate, that is, the side profile surface 21 as a whole is a vertical surface perpendicular to the surface 11 of the substrate. Figure 6 As shown, the included angle α between the chamfered plane 23 and the vertical direction of the front edge vertical surface 211 is 35.2°-36.2°, and can be specifically 35.2°, 35.7° or 36°.

[0050] In some embodiments, one, two or more needle bodies 2 may be arranged on the substrate 1 according to the clinical application scenario. When more than two needle bodies 2 are arranged, it is preferred that the needle bodies 2 are evenly spaced on the substrate 1.

[0051] Ten girls aged 20 to 22 in good health were selected as test subjects, with 5 in each group. The first group of test subjects used the microneedle 100 of this embodiment, while the second group used the existing microneedle with a relatively rounded tip. The same injection solution and the same injection volume were used by doctors with equivalent skills (microneedle puncture technique was consistent). Microneedle injection was performed on the same part of the two groups of test subjects in the same time period. After the injection, each test subject was tested for the puncture site using a pain detector of the same specification. The test results are: the test value of any one of the test subjects in the first group is lower than that of any one of the test subjects in the second group, that is, the highest test value of the test subjects in the first group is lower than the lowest test value of the test subjects in the second group. The test conclusion is that the microneedle 100 of this embodiment has the effect of reducing pain.

[0052] Example 2 This embodiment proposes a microneedle 100 capable of achieving intradermal injection, which differs from Embodiment 1 only in that the non-circular closed contour line is a symmetrical polygonal contour line, a rounded transition is set at any corner position of the symmetrical polygonal contour line, and the symmetry center axis of the symmetrical polygonal contour line coincides with the central symmetry line 247 of the first convex arc line 241.

[0053] In a feasible implementation scheme, the symmetrical polygonal contour line may be an isosceles trapezoidal contour line, whose small end is close to the first convex arc line 241 and whose large end is far away from the first convex arc line 241, and the symmetry center axis of the isosceles trapezoidal contour line is the line connecting the midpoint of the short side of the small end and the midpoint of the long side of the large end.

[0054] Ten boys aged 20 to 22 in good health were selected as test subjects, with 5 in each group. The first group of test subjects used the microneedle 100 of this embodiment, while the second group used the existing microneedle with a relatively rounded tip. The same injection solution, the same injection volume, and doctors with equivalent skills (consistent microneedle puncture techniques) were used to perform microneedle injections on the same part of the two groups of test subjects in the same time period. After the injection, each test subject was tested for the puncture site using a pain detector of the same specification. The test results are: the test value of any one of the test subjects in the first group is lower than that of any one of the test subjects in the second group, that is, the highest test value of the test subjects in the first group is lower than the lowest test value of the test subjects in the second group. The test conclusion is that the microneedle 100 of this embodiment has the effect of reducing pain.

[0055] Example 3 This embodiment proposes a microneedle 100 capable of achieving intradermal injection, which, based on the embodiment 1 or 2, further expands the injection channel 22 toward the front edge elevation 211 to further increase the injection flow rate of the needle body 2. The reason for expanding the hole toward the front edge elevation 211 is that when the microneedle is used, the tip of the front edge elevation 211 will inevitably penetrate the skin tissue, and expanding the hole toward both sides will reduce the structural strength of the needle body 2, and expanding the hole in the direction away from the front edge elevation 211 will cause the injection channel 22 to be unable to completely enter the skin tissue during injection or extraction.

[0056] The expansion of the injection channel 22 directly affects the wall thickness of the needle body 2. As a preferred embodiment, the distance between the midpoint of one end of the non-circular closed contour line facing the first convex arc line 241 and the midpoint of the first convex arc line 241 (i.e., the intersection of the central symmetry line 247 and the first convex arc line 241, and the intersection of one end of the non-circular closed contour line facing the first convex arc line 241 and the central symmetry line 247) is 35 microns to 45 microns, specifically 35 microns to 42 microns, with 36 microns, 38 microns and 40 microns being preferred.

[0057] Example 4 This embodiment provides a microneedle 100 capable of achieving intradermal injection, such as Figure 7 and Fig.10 As shown, on the basis of any one of the embodiments 1 to 3, a groove 3 is further provided on the periphery of each needle body 2, and accordingly, a groove projection 31 of the groove 3 on the surface 11 of the substrate is as shown in FIG. Figure 8 and Fig. 9 shown.

[0058] The groove 3 is a conventional structural arrangement in the microneedle, and the details are not repeated here. The size design of the groove 3 is flexibly designed according to the structural size of the needle body 2.

[0059] Example 5 This embodiment provides a microneedle 100 capable of achieving intradermal injection. The difference between this embodiment and any of the embodiments 1 to 4 is that the side profile surface 21 is not as Fig.11 Instead of the upright vertical surface shown in FIG. 1 , a two-stage design is adopted. Specifically: Fig.12 As shown, the side contour surface 21 includes an upright section 28 and a contraction section 29. The upright section 28 protrudes vertically from the surface 11 of the substrate. The contraction section 29 is located at the end of the upright section 28 away from the substrate 1, and the large end of the contraction section 29 is smoothly transitioned to the end of the upright section 28 away from the substrate 1. Based on this, the beveled plane 23 is formed by beveling the small end of the contraction section 29 toward the substrate 1, and the two ends of the boundary line 210 between the contraction section 29 and the upright section 28 respectively intersect with the two third convex arc lines 245 of the beveled plane 23. The contraction section 29 and the upright section 28 are both smooth curved surfaces. The contraction section 29 and the upright section 28 divide the side profile surface 21 according to the upright direction of the side profile surface 21, while the leading edge elevation 211 and the side elevation 212 of Example 1 divide the side profile surface 21 according to the outer peripheral contour of the side profile surface 21. The two concepts of the contraction section 29 and the upright section 28 do not conflict with the two concepts of the leading edge elevation 211 and the side elevation 212. In fact, when the chamfered plane 23 is not formed, the contraction section 29 and the upright section 28 both have corresponding leading edge elevation 211 and side elevation 212, and the leading edge elevation 211 and the side elevation 212 of the contraction section 29 are arranged one-to-one with the leading edge elevation 211 and the side elevation 212 of the upright section 28.

[0060] The side profile surface 21 is of two-stage type, and a contraction section 29 is provided at the end away from the substrate 1, so that the vertical front edge elevation of the side profile surface 21 becomes a bent front edge elevation, and the bending point is the location of the intersection line 210. It should be noted that the intersection line 210 is not a structural component of the side profile surface 21, and it is only an auxiliary line set to facilitate understanding of the scheme. Fig.13 and Fig.14 It can be seen that the intersection line of the vertical section of the side profile surface 21 and the oblique cutting plane 23 is the first oblique line 213 (at Fig.13 and Fig.14 In the figure, the first oblique line 213 also refers to the oblique cutting plane 23), and the vertical section is a section passing through the central symmetry line 247. At the same time, the intersection line of the vertical section and the front edge vertical surface 211 in the contraction section 29 is the second oblique line 214, and the angle β between the second oblique line 214 and the first oblique line 213 is 46°~61°, with 46°, 50° and 55° as preferred values; the intersection line of the vertical section and the front edge vertical surface 211 in the upright section 28 is a straight line 215, and the angle δ between the second oblique line 214 and the straight line 215 is 155°~170°.

[0061] In some embodiments, Fig.14 As shown, in the vertical section: the highest point of the projection line of the extraction port contour line 25, the vertical height from the surface 11 of the substrate is the hole height L1; the intersection of the first oblique line 213 and the second oblique line 214, the vertical height from the surface 11 of the substrate is the needle height L2; and the L1 / L2 value is 7 / 8~9 / 10.

[0062] Combination Fig.13 and Fig.14 It can be seen that the setting of the contraction section 29 makes the intersection of the second oblique line 214 and the first oblique line 213 closer to the injection channel 22 than in Example 1. This design makes the distance between the insertion tip 26 and the injection channel 22 closer, so that on the premise of ensuring that the hole height L1 remains unchanged, the needle height L2 can be further reduced, and the ratio of the injection depth to the insertion depth of the microneedle 100 can be increased, so that the needle tip insertion depth is shallower while keeping the injection volume or the extraction volume unchanged, thereby further reducing the microneedle insertion pain and wound area, making it more in line with the painless operation characteristics of the microneedle.

[0063] Example 6 like Fig.15 As shown, this embodiment proposes a microneedle 100 capable of achieving intradermal injection, which differs from the embodiment 5 only in that: the side profile surface 21 is not a two-stage type, but a one-piece type as in the embodiment 1, but in this embodiment, the front edge vertical surface 211 is arranged as a whole inclined toward the injection channel 22, so that the intersection line of the vertical section and the entire front edge vertical surface 211 is the second oblique line 214, at this time, the angle β between the second oblique line 214 and the first oblique line 213 is 36°~39°, and 37° and 38° are the most preferred. The vertical section is a section passing through the central symmetry line 247.

[0064] In some embodiments, Fig.15 As shown, in the vertical section: the highest point of the projection line of the extraction port contour line 25, the vertical height from the surface 11 of the substrate is the hole height L1; the intersection of the first oblique line 213 and the second oblique line 214, the vertical height from the surface 11 of the substrate is the needle height L2; and the L1 / L2 value is 7 / 8~9 / 10.

[0065] Combination Fig.15 It can be seen that the front edge vertical surface 211 is arranged as a whole to be inclined toward the injection channel 22, so that the intersection of the second oblique line 214 and the first oblique line 213 is closer to the injection channel 22 than in Example 1. This design makes the insertion tip 26 and the injection channel 22 closer, so that on the premise of ensuring that the hole height L1 remains unchanged, the needle height L2 can be further reduced, and the ratio of the injection depth to the insertion depth of the microneedle 100 can be increased, so that the needle tip insertion depth is shallower while keeping the injection volume or the extraction volume unchanged, thereby further reducing the microneedle insertion pain and wound area, making it more in line with the painless operation characteristics of the microneedle.

[0066] Compared with the two-stage profile surface of the fifth embodiment, the side profile surface 21 of the present embodiment is easier to process.

[0067] It should be noted that the structures, proportions, sizes, etc. drawn in the drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the present invention, so they have no substantial technical significance. Any modification of the structure, change of the proportional relationship or adjustment of the size should still fall within the scope of the technical content disclosed by the present invention without affecting the effects and purposes that can be achieved by the present invention. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" quoted in this specification are only for the convenience of description, and are not used to limit the scope of the implementation of the present invention. The change or adjustment of their relative relationship should also be regarded as the scope of the implementation of the present invention without substantially changing the technical content.

[0068] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A microneedle capable of achieving intradermal injection, comprising a substrate (1) and a needle body (2) disposed on the substrate (1), characterized in that: The needle body (2) comprises: a side profile surface (21) protruding from the surface of the substrate (1), the side profile surface (21) being a solid structure, the side profile surface (21) comprising a front edge face (211) and side faces (212) symmetrically arranged on both sides of the front edge face (211), the front edge face (211) and the side faces (212) on both sides being smoothly transitioned and connected; an injection channel (22) opened on the solid structure in the side profile surface (21); and a chamfered plane (23) extending from the side away from the side profile surface (21). One end of the substrate (1) is beveled toward the substrate (1), and the intersection line of the beveled plane (23) and the side profile surface (21) is the needle blade (24) of the needle body (2), the intersection line of the beveled plane (23) and the injection channel (22) is the injection port contour line (25) of the needle body (2), and the intersection of the high end of the beveled plane (23) and the front edge vertical surface (211) is the insertion tip (26) of the needle body (2); wherein the projection contour line of the needle blade (24) on the surface of the substrate (1) is the projection contour line of the needle blade The needle blade projection line includes: a first convex arc line (241) corresponding to the front edge elevation (211); and multiple arc lines corresponding to the side elevations (212) on both sides, wherein the two multiple arc lines are identical and are symmetrically arranged at both ends of the first convex arc line (241), wherein any of the multiple arc lines includes a first concave arc line (242), a second convex arc line (243), a second concave arc line (244), a third convex arc line (245), and an extension line (246) which are sequentially tangently connected from the high end to the low end of the chamfered plane (23). , the high end of the first inward concave arc (242) is tangentially transitionally connected to the end of the first outward convex arc (241); wherein a reference point is set on the second inward concave arc (244), and the portion of the multi-arc from the reference point to the first outward convex arc (241) shows a gradually inwardly contracting oblique trend toward the first outward convex arc (241), and the portion of the multi-arc from the reference point to the tail of the extension line (246) shows a gradually outwardly expanding oblique trend toward the tail of the extension line (246), or shows a trend of gradually expanding outwards and then maintaining the same inclination.

2. The microneedle capable of achieving intradermal injection according to claim 1, characterized in that: On the bevel plane (23), a connecting line segment between the reference points of the two second inwardly concave arcs (244) is set as a reference line segment (27), and a closed area is formed between the reference line segment (27) and the first outwardly convex arc (241) and the two multiple arcs, and the injection port contour line (25) is located within the closed area.

3. The microneedle capable of intradermal injection according to claim 2, characterized in that: In the needle blade projection line: the length of the reference line segment (27) is 110 micrometers to 130 micrometers.

4. The microneedle capable of intradermal injection according to any one of claims 1 to 3, characterized in that: The needle blade (24) is on the projection contour line of the surface of the substrate (1): the radius of the first convex arc (241) is R1=30 microns~40 microns, and its corresponding central angle γ is 60°~65°; the radius of the second convex arc (243) is R2=118 microns~122 microns, and the second convex arc (243) smoothly transitions to the first convex arc (241) through the first concave arc (242); the radius of the second concave arc (244) is R3=150 microns~160 microns, and the second concave arc (244) smoothly transitions to the extension line (246) through the third convex arc (245), and an outward-expanded shoulder is formed at the third convex arc (245); the extension line (246) is a vertical line, and the two extension lines (246) are parallel; or, the extension line (246) is an oblique straight line or an oblique arc.

5. The microneedle capable of intradermal injection according to any one of claims 1 to 3, characterized in that: The needle body (2) is provided with an injection channel (22), and the projection contour of the injection port contour line (25) on the surface of the substrate (1) is a non-circular closed contour line, and the distance between any point on the non-circular closed contour line and the corresponding position of the needle blade projection line is d, 35 micrometers ≤ d ≤ 45 micrometers.

6. The microneedle capable of achieving intradermal injection according to claim 5, characterized in that: The non-circular closed contour line is an elliptical contour line, and the major axis of the elliptical contour line coincides with the central symmetry line (247) of the first convex arc line (241); or, the non-circular closed contour line is a symmetrical polygonal contour line, and any corner position of the symmetrical polygonal contour line is provided with a rounded transition, and the symmetry axis of the symmetrical polygonal contour line coincides with the central symmetry line (247) of the first convex arc line (241).

7. The microneedle capable of achieving intradermal injection according to claim 6, characterized in that: The distance between the intersection point of the central symmetry line (247) and the first convex arc line (241) and the intersection point of one end of the non-circular closed contour line facing the first convex arc line (241) and the central symmetry line (247) is 35 microns to 45 microns.

8. The microneedle capable of intradermal injection according to any one of claims 1 to 3, characterized in that: The side profile surface (21) protrudes vertically from the surface of the substrate (1) as a whole, and the included angle α between the chamfered plane (23) and the upright direction of the front edge vertical surface (211) is 35.2° to 36.2°.

9. The microneedle capable of intradermal injection according to any one of claims 1 to 3, characterized in that: The side profile surface (21) comprises: an upright section (28) protruding vertically from the surface of the substrate (1); a contraction section (29), the large end of the contraction section (29) smoothly transitioningly connecting with the end of the upright section (28) away from the substrate (1); the beveled plane (23) is formed by beveling the small end of the contraction section (29) toward the substrate (1), and the two ends of the intersection line (210) between the contraction section (29) and the upright section (28) respectively intersect with two third convex arcs (245) of the beveled plane (23); the intersection line of the vertical section of the side profile surface (21) and the beveled plane (23) is a first oblique line (213); the central symmetry line (247) of the first convex arc (241) is located in the vertical section; the vertical section The intersection line of the vertical section and the front edge vertical surface (211) in the contraction section (29) is a second oblique line (214), and the angle β between the second oblique line (214) and the first oblique line (213) is 46°~61°; the intersection line of the vertical section and the front edge vertical surface (211) in the upright section (28) is a straight line (215), and the angle δ between the second oblique line (214) and the straight line (215) is 155°~170°; in the vertical section: the highest point of the projection line of the extraction port contour line (25) is at a vertical height of the hole height L1 from the surface of the substrate (1); the intersection point of the first oblique line (213) and the second oblique line (214) is at a vertical height of the needle height L2 from the surface of the substrate (1); and the value of L1 / L2 is 7 / 8~9 / 10.

10. The microneedle capable of intradermal injection according to any one of claims 1 to 3, characterized in that: The front edge vertical surface (211) is arranged as a whole to be inclined toward the injection channel (22), and the two side vertical surfaces (212) are as a whole vertically protruding from the surface of the substrate (1); the intersection line of the vertical section of the side profile surface (21) and the oblique cutting plane (23) is a first oblique line (213); the central symmetry line (247) of the first outer convex arc line (241) is located in the vertical section; the intersection line of the vertical section and the front edge vertical surface (211) is a second oblique line. line (214), the angle β between the second oblique line (214) and the first oblique line (213) is 36°~39°; in the vertical section: the highest point of the projection line of the extraction port contour line (25) is at a vertical height of the hole height L1 from the surface of the substrate (1); the intersection of the first oblique line (213) and the second oblique line (214) is at a vertical height of the needle height L2 from the surface of the substrate (1); and the value of L1 / L2 is 7 / 8~9 / 10.

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