Injection needle and needle hub equipped with injection needle

Abstract

To provide an injection needle that can suppress piercing resistance while reducing an amount of silicone oil usage and contributes to suppression of environmental pollution on such as a manufacturing facility, and to provide a needle hub including the injection needle.SOLUTION: An injection needle 2 has a region of a length of 2 / 3×L in an axial direction from a needle tip to which silicone oil is applied when L represents the whole length in an axial direction G of blade surfaces 4A, 4B forming a needle tip part 4. A needle hub includes the injection needle 2.SELECTED DRAWING: Figure 3A

Description

Technical Field

[0001] The present invention relates to an injection needle that punctures a target and a needle hub provided with this injection needle.

Background Art

[0002] In an injection needle, reducing the piercing resistance that occurs when piercing a target is a major issue. To address this, various shapes of the tip portion of injection needles have been proposed. Among them, there has been proposed a puncture needle that suppresses an increase in piercing resistance by reducing the tip angle regardless of the length of the blade surface (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, although various shapes of the tip portion, including the shape described in Patent Document 1, have been proposed, there is a limit to suppressing the piercing resistance only by devising the shape of the tip portion. For this reason, silicone oil is often applied to the injection needle for lubrication purposes. Usually, silicone oil is applied from the tip of the needle to about two-thirds of the total length of the injection needle, and silicone oil is applied not only to the tip portion composed of the blade surface but also to the side surface of the shaft portion on the proximal side thereof.

[0005] The silicone oil applied to the injection needle comes into direct contact with the human body upon puncture. As a result, there is a risk of deterioration due to the reaction of the silicone oil with the active ingredients in the drug solution, or adverse effects on the human body from silicone resin microparticles that detach from the silicone oil. Furthermore, since the silicone oil is applied to about two-thirds of the total length of the injection needle, there is a risk that the silicone oil may adhere to the needle hub during application, especially with injection needles that have a short needle protrusion. If silicone oil adheres to the needle hub, not only is the silicone oil wasted, but there is also a risk of contamination of jigs in the next process. The needle hub is the part that is held by the hand when attaching the injection needle to the syringe, so there is a risk of hands becoming dirty or hands slipping, making the attachment process difficult.

[0006] Therefore, the object of the present invention is to solve the above problems and to provide an injection needle and a needle hub equipped with this injection needle that can reduce the amount of silicone oil used while suppressing puncture resistance and also contribute to suppressing environmental pollution of manufacturing equipment, etc. [Means for solving the problem]

[0007] In one embodiment of the present invention, if the total axial length of the cutting surface forming the needle tip is L, silicone oil is applied to a region extending 2 / 3 × L from the needle tip in the axial direction.

[0008] A needle hub according to one embodiment of the present invention is a needle hub to which the above-mentioned injection needle is attached. [Effects of the Invention]

[0009] As described above, the present invention provides an injection needle and a needle hub equipped with this injection needle that can reduce the amount of silicone oil used while suppressing puncture resistance, and also contribute to reducing environmental pollution of manufacturing equipment, etc. [Brief explanation of the drawing]

[0010] [Figure 1A] This is a perspective view showing the external shape of a needle hub according to one embodiment of the present invention. [Figure 1B]Figure 1A is a side cross-sectional view of the needle hub. [Figure 2A] This is a perspective view showing the external shape of an injection needle according to one embodiment of the present invention. [Figure 2B] Figure 2A shows (a) a plan view and (b) a side cross-sectional view of the injection needle. [Figure 3A] This is a plan view of the injection needle showing the area to which silicone oil is applied in the example. [Figure 3B] This is a plan view of an injection needle showing the area to which silicone oil is applied in a conventional example. [Figure 4] This diagram shows an overview of a device for applying silicone oil to injection needles. [Figure 5A] This diagram shows the process of applying silicone oil to an injection needle, specifically the state of the needle before it is immersed in the silicone solution. [Figure 5B] This diagram shows the process of applying silicone oil to an injection needle, specifically the state in which the injection needle is immersed in the silicone solution. [Figure 5C] This diagram shows the process of applying silicone oil to an injection needle, specifically the state after air blowing has been performed. [Figure 6A] This graph shows the results of measuring the penetration resistance of an injection needle that was not coated with silicone oil. [Figure 6B] This graph shows the results of measuring the penetration resistance of an injection needle in an example where silicone oil was applied to a region of 1.2 mm from the needle tip. [Figure 6C] This graph shows the results of measuring the penetration resistance of an injection needle in an example where silicone oil was applied to a region of 1.6 mm from the needle tip. [Figure 6D] This graph shows the results of measuring the penetration resistance of an injection needle in an example where silicone oil was applied to a region up to 2.0 mm from the needle tip. [Figure 6E] This graph shows the results of measuring the penetration resistance of an injection needle with silicone oil applied to the entire cutting surface of the needle tip. [Modes for carrying out the invention]

[0011] Next, specific embodiments of the present invention will be described in detail while referring to the drawings. In each figure, corresponding members having the same function are denoted by the same reference numerals.

[0012] (Needle hub according to one embodiment of the present invention) First, an explanation of a needle hub according to one embodiment of the present invention will be given while referring to FIGS. 1A and 1B. FIG. 1A is a perspective view showing the outer shape of a needle hub according to one embodiment of the present invention. FIG. 1B is a side cross-sectional view of the needle hub shown in FIG. 1A.

[0013] The tip of the syringe to which the needle hub 10 according to this embodiment is attached has a frustum shape with a Luer taper formed thereon. Generally, for the Luer taper for attaching the needle hub, there are a more pull-resistant lock type (screw type) and a simpler structure slip type (snap-in type), but the lock type is adopted in this embodiment. More specifically, a male Luer lock connector defined in ISO80369-7:2021 (Small-bore connectors for liquids and gases in the healthcare field - Part 7: Connectors for intravascular or subcutaneous syringe applications) is adopted.

[0014] The needle hub 10 according to this embodiment has a frustum-shaped recess 12 that fits with the male Luer lock connector defined in ISO80369-7:2021, and the injection needle 2 is attached on the front side of the recess 12. The injection needle 2 can be attached to the needle hub 10 by any known method.

[0015] (Injection needle according to one embodiment of the present invention) Next, an explanation of the injection needle 2 according to one embodiment of the present invention will be given while referring to FIGS. 2A and 2B. FIG. 2A is a perspective view showing the outer shape of an injection needle according to one embodiment of the present invention. FIG. 2B is a (a) plan view and (b) side cross-sectional view of the injection needle shown in FIG. 2A.

[0016] In this embodiment, the injection needle 2 consists of a first cutting surface 4A located on the proximal end side and a second cutting surface 4B located on the needle tip P side. In other words, the injection needle 2 in this embodiment is a so-called lancet-type injection needle. By forming the second cutting surfaces 4B, which are bevel surfaces, on both sides of the center line extending in the axial direction, the resistance to puncture can be reduced. Examples of needle sizes for the injection needle 2 include those from 21G to 32G as specified in ISO 9626:2016. In this embodiment, in order to further reduce the resistance to puncture, silicone oil is applied to the injection needle 2 for lubrication purposes, as will be described later. The standards for silicone oil used as a lubricant for injection needles and syringes are specified in Pharmaceuticals and Medical Devices Agency Notification No. 327 of the Medical Devices Standards.

[0017] (Applying silicone oil) Generally, there are two methods for applying silicone oil to injection needles: dipping and spraying. In both methods, silicone oil is applied from the tip of the blade to about two-thirds of the total length of the needle. Therefore, silicone oil is applied not only to the tip of the injection needle, which is composed of the blade surface, but also to the sides of the shaft closer to the proximal end. The silicone oil is diluted with a diluent, and after application, the diluent is evaporated at room temperature to fix the applied silicone oil in place.

[0018] In the dipping method, the concentration of the silicone oil changes over time due to the evaporation of the diluent, so concentration control is necessary. Also, since silicone oil is applied to the inner surface of the needle, which is not meant to be used, it is not only wasteful but also increases the possibility of deterioration of the chemical solution. Therefore, in the dipping method, when immersing the needle tip in silicone oil, the inside of the needle is blown with air to prevent silicone oil from adhering to the inner surface of the needle. When blowing with air, there is a risk that the silicone oil will be scattered by the bubbles released from the needle tip onto the needle hub and equipment, so it is important to blow with air at the appropriate pressure.

[0019] In the case of a spray type, the silicone oil is sprayed in particulate form, which may adhere to components and equipment other than the injection needle, such as the needle hub and jigs, potentially contaminating the manufacturing environment. Considering these factors, the present invention employs a dipping method, which has a lower risk of contamination of the manufacturing environment, to apply the silicone oil to the injection needle 2.

[0020] As described above, the silicone oil applied to the injection needle comes into direct contact with the human body through puncture. As a result, there is a risk of deterioration due to the reaction of the silicone oil with the active ingredients in the drug solution, or adverse effects on the human body due to silicone resin microparticles detached from the silicone oil. Furthermore, when silicone oil is applied to about two-thirds of the total length of the injection needle, especially with injection needles that have a short needle protrusion, there is a risk that the silicone oil may adhere to the needle hub during application. If silicone oil adheres to the needle hub, not only is the silicone oil wasted, but there is also a risk of contamination of the jig in the next process. The needle hub is the part that is held by the hand when attaching the injection needle to the syringe, so there is a risk of hands becoming dirty or hands slipping, making the attachment operation difficult.

[0021] To address this, the inventors conducted tests using a so-called lancet-type injection needle 2, varying the area to which silicone oil was applied, and measuring the needle's penetration resistance. As a result, they found that it is possible to create an injection needle 2 that can suppress penetration resistance while reducing the amount of silicone oil used, and also contribute to reducing environmental pollution of manufacturing equipment, etc.

[0022] (Examples) Figure 3A is a plan view of the injection needle 2 showing the area to which silicone oil is applied in the embodiment. Figure 3B is a plan view of the injection needle 102 showing the area to which silicone oil is applied in the conventional example. In the conventional example, silicone oil is applied from the needle tip P to an area approximately two-thirds of the total length of the injection needle 102. As a result, silicone oil is applied not only to the needle tip portion 104 of the injection needle 102, which is composed of cutting surfaces 104A and 104B, but also to the side surface of the shaft portion 106 closer to the base end.

[0023] In the embodiment, the injection needle 2 has a gauge size of 22G, and the total length L of the cutting surfaces 4A and 4B constituting the needle tip 4 is 3.32 mm. Here, the total length L of the cutting surfaces 4A and 4B constituting the needle tip 4 is the distance from the needle tip P to the most proximal end of the cutting surfaces 4A and 4B (actually the first cutting surface 4A) in the axial direction G, as shown in Figure 3A. The angle that the first cutting surface 4A makes with respect to the axial direction G is approximately 9 degrees. The total length L2 of the second cutting surface 4B is 1.6 mm. Here, the total length L2 of the second cutting surface 4B is the distance from the needle tip P to the most proximal end of the second cutting surface 4B in the axial direction G, as shown in Figure 3A.

[0024] Silicone oil was applied to the following areas from the needle tip P to 1.2 mm, from the needle tip P to 1.6 mm, from the needle tip P to 2.0 mm, and from the needle tip P to an area greater than or equal to the total length L of the blade surface, using the silicone oil application method shown below. Here, the area from the needle tip P to 2.0 mm refers to the area from the needle tip P to approximately 2 / 3 of the total length L of the blade surfaces 4A and 4B. The area from the needle tip P to 1.6 mm refers to the area from the needle tip P to the total length L2 of the second blade surface 4B. Furthermore, the area from the needle tip P to 1.2 mm refers to the area from the needle tip P to 3 / 4 of the total length L2 of the second blade surface 4B.

[0025] As is clear from Figure 3A, the lumen edge N located on the proximal end side of the needle tip 4 is situated between the proximal end of the second cutting surface 4B and the proximal end of the needle tip 4 (i.e., the proximal end of the first cutting surface 4A). On the proximal side of the lumen edge N, the internal region of the injection needle 2 is covered by the outer shell of the injection needle 2 around its entire circumference. On the distal side of the lumen edge N, at least a portion of the internal region of the injection needle 2 is not covered by the outer shell of the injection needle 2 and is open to the outside. Typically, the total length of the first cutting surface 4A is greater than 1 / 3 of the total length L of the cutting surfaces 4A and 4B, and the region from the needle tip P to 2 / 3 of the total length L of the cutting surfaces 4A and 4B corresponds to the entirety of the second cutting surface 4B and a portion of the first cutting surface 4A.

[0026] <Method for applying silicone oil> Next, with reference to Figures 4 and 5A to 5C, we will explain the application method in which silicone oil is actually applied to the injection needle 2. Figure 4 is a diagram showing an overview of the apparatus for applying silicone oil to the injection needle. Figure 5A shows the process of applying silicone oil to the injection needle, and shows the state before the injection needle is immersed in the silicone solution. Figure 5B shows the state after the injection needle has been immersed in the silicone solution. Figure 5C shows the state after air blowing has been performed. As shown in Figure 4, this coating method involves attaching a dipping jig T to an automatic load testing machine, and then attaching a needle hub 10, on which the aforementioned injection needle 2 is mounted, to the dipping jig T.

[0027] The silicone solution used for coating is shown below. Silicone: KF-8013, manufactured by Shin-Etsu Chemical Co., Ltd. Diluent: AGC Inc. AMOLEA (registered trademark) AT1 Dilution concentration: 4.5-7.5% The automatic load testing machine used for coating was the MAX-1KN-P-1 automatic load testing machine manufactured by Nippon Keisoku System Co., Ltd.

[0028] The dipping jig T has a protrusion with a Luer taper that corresponds to the recess 12 of the needle hub 12. Through this interlocking of protrusions and recesses, the needle hub 10, with the injection needle 2 attached, is mounted to the automatic load testing machine (dipping jig T). As shown by the arrows in Figure 4, the dipping jig T is movable vertically, allowing the injection needle 2 to be immersed in the silicone oil S at a set immersion depth.

[0029] By setting the desired immersion depth on the automatic load testing machine and operating it, the state shown in Figure 5A can be changed to the immersion state shown in Figure 5B. Furthermore, as shown in Figure 5C, air blowing can be performed to prevent silicone oil from adhering to the inner surface of the injection needle 2. At this time, air blowing should be performed with the appropriate blowing pressure to prevent the silicone oil from being blown out by air bubbles from the needle tip and scattering onto the needle hub or equipment. Then, the injection needle 2, which was immersed in the silicone oil, is pulled up and returned to the state shown in Figure 5A. After application, the diluent can be evaporated at room temperature to fix the applied silicone oil.

[0030] Depending on the immersion depth set in the automatic load testing machine, silicone oil can be applied to the region shown in Figure 3A. The thickness of the applied silicone oil is 100 nm to 1000 nm.

[0031] <Method for measuring puncture resistance> The penetration resistance of injection needle 2, to which silicone oil had been applied using the above application method, was measured using the automatic load testing machine used for applying the silicone oil described above. Injection needle 2 punctured the silicone rubber sheet at a puncture speed of 10 mm / min, and the penetration resistance at that time was measured with a load cell.

[0032] The test conditions are as follows. Testing equipment: Automatic load testing machine (MAX-1KN-P-1) manufactured by Nippon Keisoku System Co., Ltd., special specifications I-4-19 Load cell: JCL-M10N (Capacity: 10N) Target membrane for puncture: Silicone rubber sheet, hardness 20 (Durometer A), thickness: 10 mm Test speed: 10 mm / min.

[0033] <Measurement results of puncture resistance> Next, the results of the penetration resistance measurements using the above measurement method will be explained with reference to Figures 6A to 6D. Figure 6A is a graph showing the results of measuring the penetration resistance of an injection needle without silicone oil coating. Figure 6B is a graph showing the results of measuring the penetration resistance of an injection needle in an example where silicone oil was applied to a region of 1.2 mm from the needle tip. Figure 6C is a graph showing the results of measuring the penetration resistance of an injection needle in an example where silicone oil was applied to a region of 1.6 mm from the needle tip. Figure 6D is a graph showing the results of measuring the penetration resistance of an injection needle in an example where silicone oil was applied to a region of 2.0 mm from the needle tip. Figure 6E is a graph showing the results of measuring the penetration resistance of an injection needle with silicone oil applied to the entire cutting surface of the needle tip.

[0034] In all graphs, the horizontal axis shows the puncture depth (mm), and the vertical axis shows the penetration resistance (N: Newtons). In all cases—Case A: No coating, Case B: 1.2 mm coating, Case C: 1.6 mm coating, Case D: 2.0 mm coating, and Case E: Full coating—there was a tendency for penetration resistance to increase as the puncture depth of the injection needle increased. The average penetration resistance in Case A was 1.74 N, in Case B it was 1.16 N, in Case C it was 1.07 N, in Case D it was 1.05 N, and in Case E it was 0.98 N.

[0035] Compared to the average penetration resistance in the uncoated case, the average penetration resistance in case B was 66.7%, in case C it was 61.7%, in case D it was 60.2%, and in case E it was 56.2%. When silicone oil was applied to the entire cutting surface of the needle tip, as in case E, a significant reduction in penetration resistance was observed compared to the uncoated case (A). However, even in cases B through D, the penetration resistance was reduced to less than 2 / 3 compared to the uncoated case (A), indicating a significant reduction in penetration resistance.

[0036] In Case D, shown in Figure 4D, silicone oil was applied to a region extending approximately two-thirds of the total length L (=3.32 mm) from the needle tip P to the cutting surfaces 4A and 4B in the axial direction G. The average penetration resistance was 60.2% of that in Case A, where no silicone oil was applied. This demonstrated that penetration resistance could be sufficiently reduced, and pain during puncture could be expected to be alleviated. In this case, it is thought that even for needle tips other than lancet-type needles, applying silicone oil to a region extending two-thirds of the total length L from the needle tip P to the cutting surface would sufficiently reduce penetration resistance.

[0037] In Case C, shown in Figure 4C, silicone oil is applied to the area from the needle tip P to the second cutting surface 4B over a total length L2 (=1.6 mm) in the axial direction G. The average penetration resistance is 61.7% of that in Case A, where no silicone oil is applied. Theoretically, it is considered effective to lubricate the second cutting surface 4B on the needle tip P side, which is formed to reduce penetration resistance, and this effect has been demonstrated. In Case C as well, it has been demonstrated that penetration resistance is sufficiently reduced, and pain during puncture can be expected to be alleviated.

[0038] In Case B, shown in Figure 4B, silicone oil is applied to a region covering 3 / 4 of the total length L2 (=1.6 mm) from the needle tip P to the second cutting surface 4B in the axial direction G. The average penetration resistance is 66.7% of that in Case A, where no silicone oil is applied. Surprisingly, it has been demonstrated that even when silicone oil is applied to 3 / 4 of the total length L2 from the needle tip P to the second cutting surface 4B, the penetration resistance is sufficiently reduced, and pain during puncture can be expected to be alleviated.

[0039] As described above, if the total length in the axial direction G of the cutting surfaces 4A and 4B that form the needle tip portion 4 is L, then when silicone oil is applied to a region of length 2 / 3 × L from the needle tip P in the axial direction (Case D), the amount of silicone oil used can be reduced while suppressing penetration resistance.

[0040] Furthermore, in a lancet-type injection needle 2 in which the needle tip 4 is composed of a first cutting surface 4A on the proximal end side and a second cutting surface 4B on the needle tip P side, if the total length of the second cutting surface 4B in the axial direction G is L2, then when silicone oil is applied to a region of length L2 from the needle tip in the axial direction G (Case C), the amount of silicone oil used can be further reduced compared to Case D above. Compared to Case D above, the penetration resistance is slightly higher, but the penetration resistance can be sufficiently suppressed.

[0041] Furthermore, in a lancet-type injection needle 2 in which the needle tip 4 is composed of a first cutting surface 4A on the proximal end side and a second cutting surface 4B on the needle tip P side, if the total length of the second cutting surface 4B in the axial direction G is L2, then when silicone oil is applied to a region of 3 / 4 × L2 in the axial direction G from the needle tip P, the amount of silicone oil used can be further reduced compared to case C above. Compared to cases C and D above, the penetration resistance is slightly higher, but it can be said that the penetration resistance can be sufficiently suppressed.

[0042] As is clear from Figure 3A, the lumen edge N located on the proximal end side of the needle tip 4 is situated between the proximal end of the second cutting surface 4B and the proximal end of the needle tip 4 (i.e., the proximal end of the first cutting surface 4A). Therefore, even when silicone oil is applied to the area from the needle tip P to the lumen edge N located on the proximal end side of the needle tip 4, penetration resistance can be suppressed while reducing the amount of silicone oil used.

[0043] In all of the above cases, it is possible to ensure that silicone oil is not applied to the shaft 6 of the injection needle 2, thereby suppressing environmental pollution of manufacturing equipment, etc. Therefore, it is possible to provide an injection needle 2 that can reduce the amount of silicone oil used while suppressing penetration resistance, and also contribute to suppressing environmental pollution of manufacturing equipment, etc.

[0044] Similarly, in the needle hub 10 equipped with this injection needle 2, the amount of silicone oil used can be reduced while suppressing penetration resistance, and environmental pollution of manufacturing equipment can be suppressed. It should be noted that the needle hub 10 is not limited to the shape described above, and any other shape or type of needle hub can be used.

[0045] Although embodiments of the present invention have been described, the disclosed content may change in the details of the configuration, and changes in the combination and order of elements in the embodiments can be realized without departing from the claimed scope and spirit of the present invention. [Explanation of symbols]

[0046] 2 Syringe needle 4 Needle tip 4A 1st blade surface 4B 2nd blade surface 6. Shaft section 10-needle hub 12 recesses 102 Syringe needle 104 Needle tip 104A 1st blade surface 104B 2nd blade surface 106 Shaft P Needle tip N Lumen edge T Dipping Jig S Silicone oil G-axis direction

Claims

1. An injection needle characterized in that, if L is the total length in the axial direction of the cutting surface that forms the needle tip, silicone oil is applied to a region extending 2 / 3 × L from the needle tip in the axial direction.

2. A lancet-type injection needle in which the needle tip is composed of a first cutting surface on the proximal end and a second cutting surface on the tip end, An injection needle characterized in that, with L2 being the total length in the axial direction of the second cutting surface, silicone oil is applied to a region with a length L2 from the needle tip in the axial direction.

3. A lancet-type injection needle in which the needle tip is composed of a first cutting surface on the proximal end and a second cutting surface on the tip end, An injection needle characterized in that, with L2 being the total length in the axial direction of the second cutting surface, silicone oil is applied to a region extending 3 / 4 × L2 in the axial direction from the needle tip.

4. An injection needle characterized by having silicone oil applied to the area from the needle tip to the lumen edge located on the proximal end of the needle tip.

5. An injection needle according to any one of claims 1 to 4, characterized in that the needle size is between 21G and 32G as defined in ISO 9626:2016.

6. A needle hub characterized by being fitted with an injection needle according to any one of claims 1 to 5.

7. The needle hub according to claim 6, characterized by having a trapezoidal recess that mates with a male Luer lock connector as defined in ISO 80369-7:2021.

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