Syringe, syringe and injection device for injecting a high-viscosity medium

Abstract

To provide a syringe (12) for injector for injecting a highly viscous medium.SOLUTION: A syringe (12) includes a distal end (18) and a proximal end (20). The syringe (12) has a hollow cylindrical shape and forms a chamber for housing a highly viscous medium. The proximal end (20) has an aperture through which a plunger rod unit (14) can be inserted into the chamber. At the distal end (18) is formed a luer lock connector (22), the luer lock connector (22) including an outer cone (40) comprising a relatively wide aperture (42) for supplying the highly viscous medium and a sleeve-shaped part (44) comprising a female thread (46). The syringe (12) has an NPO minimum resistance exceeding 90 N.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to syringes, injection devices and injection apparatuses for injecting highly viscous media. In particular, these syringes, injection devices and injection apparatuses can be used for injecting or administering highly viscous pharmaceutical media.

Background Art

[0002] Syringes are used, for example, in the medical and cosmetic fields, and are used to inject a medium contained in the syringe into a patient's body. For example, within the framework of cosmetic treatment of a patient's skin, a skin filler is injected, for example, under the patient's skin surface. In cosmetic applications, highly viscous media are generally used. The medium contained in the syringe may include various forms of fluids, pasty or liquid substances, and mixtures.

[0003] In order to keep the skin puncture required for injection and the associated pain of the patient as small as possible, a needle is preferably provided with a very small cannula thickness ("gauge"). This is particularly applicable to use on a patient's face.

[0004] The combination of the smallest possible cannula thickness and the highly viscous medium to be injected places a high load on the syringe or syringe barrel. In particular, the high pressure within the syringe can lead to mechanical failure of the injection unit. However, since mechanical failure of the syringe must be avoided, in conventionally known syringes, the possibility of using a needle with a small cannula thickness is limited, which also necessarily involves the above-mentioned disadvantages for the patient.

Summary of the Invention

Problems to be Solved by the Invention

[0005] Accordingly, the object of the present invention is to overcome the drawbacks based on the prior art. In particular, the object of the present invention is to provide a syringe, a syringe device and an injection device that enable the use of a needle with a small cannula thickness for injecting a highly viscous medium.

Means for Solving the Problem

[0006] This problem is solved by the syringe, the syringe device and the injection device described in each independent patent claim. Improvements and embodiments of the syringe, the syringe device and the injection device are described in the dependent claims and the following description.

[0007] One aspect of the present invention relates to a syringe for a syringe for injecting or administering a highly viscous medium. In one embodiment, the highly viscous medium is characterized by a storage elastic modulus G' of at least 30 Pa and at most 150 Pa, in particular at least 50 Pa and at most 100 Pa, or at least 70 and at most 90 Pa. The loss factor tan δ may be from 0.2 to 0.8, in particular from 0.3 to 0.6 or from 0.4 to 0.5. This may be, for example, a hyaluronic acid filler. The viscosity can be measured using a plate-plate measurement system at 25 °C and an atmospheric pressure of 1013.25 hPa, in particular at a frequency of 1 Hz (e.g., the rheometer MCR302 from Anton Paar). The measurement may be carried out, for example, by the method described in ISO standard 6721-10-2015-09. The syringe has a distal end and a proximal end. The syringe is hollow cylindrical and forms a chamber for containing the highly viscous medium. The proximal end has an opening through which the plunger rod unit can be inserted or is inserted into the chamber. The plunger rod unit is movable in the chamber in the direction of the longitudinal axis of the chamber and is slidably guided in the syringe.

[0008] A Luer lock connector is formed at the distal end of the syringe. The Luer lock connector has an outer cone with a relatively wide opening for supplying a high-viscosity medium and a sleeve-shaped portion with female threads. The Luer lock connector forms part of a Luer lock coupling system and is configured to cooperate with a corresponding member of the Luer lock connector formed on the needle unit. The outer cone can also be described as a conical nozzle that protrudes beyond the distal end of the syringe and can lead out the high-viscosity medium from the chamber. The outer cone also forms part of the Luer lock coupling system and also cooperates with the complementary corresponding member of the needle unit. In the Luer lock coupling system, the outer cone and the sleeve-shaped portion surrounding the outer cone are arranged coaxially with each other. The Luer lock connector of the syringe may be formed and dimensioned, in particular, within the framework of ISO standard 80369-7:2016-12-01. This enables the syringe according to the invention to be used together with a plurality of different needle units standardized in the field of Luer lock couplings.

[0009] The syringe has an NPO minimum resistance of more than 90 N based on the present invention. Preferably, the syringe may have an NPO minimum resistance of more than 95 N, preferably more than 100 N, and more preferably more than 103 N. In particular, the syringe may have an NPO minimum resistance of 90 N to 105 N, preferably 95 N to 103.5 N, and preferably 98 N to 102 N. NPO means "Needle Pop Off" and represents the sudden dissociation or detachment of the needle unit from the syringe, in particular the needle unit coupled to the syringe via the Luer lock connection. The needle unit (triggered by applying force to the syringe via the plunger rod unit) begins to rotate under high pressure and begins to disengage from the syringe at high speed, i.e., the inner cone of the needle unit, which is complementary to the outer cone of the syringe, disengages.

[0010] The NPO minimum resistance (the "needle drop" minimum resistance) is the threshold of the force applied to the plunger rod unit that is brought into the syringe and is in an operative connection with the syringe within the framework of the test method described below. The NPO minimum resistance is defined by the fact that "needle drop" occurs in no more than 1.8% of the syringes tested below the threshold value. To obtain significant results regarding the NPO minimum resistance, at least 56 measurements of syringes of the same type and configuration are required.

[0011] The test method for measuring the NPO resistance, in particular the NPO minimum resistance and the average NPO resistance, assumes that the syringe to be tested is placed vertically in the testing machine and held in the region of the proximal end of the syringe. The testing machine to be used is the "TesT 106.2kN" model universal testing machine of "TesT" company. This test method allows the use of this universal testing machine or a comparable universal testing machine.

[0012] The syringe to be tested is coupled to the needle unit via a luer lock connector, and the needle unit is screwed onto the distal end of the syringe with a torque of 12 Ncm to form a luer lock joint using a luer lock connector mating member. Specifically, it is desirable that the test method be carried out using a needle unit “TSK STERiJECT Hypodermic Needle” Ref.: PRC - 30013l, 30G×1 / 2 or a needle unit comparable thereto. The needle unit used in this test method has, as a luer lock connector mating member, an inner cone and two tip portions arranged on the outer peripheral surface of the needle base of the needle unit. The needle unit used in this test method has a cannula or hollow needle with a thickness of 30G and a length of 13 mm (30G×1 / 2). The cannula has to be flattened with a hammer before the test method is carried out for the test and thereby closed. For this test method, after the needle unit is screwed onto the syringe, a dry luer lock joint can be formed by filling the chamber with a high - viscosity medium. This test method can be carried out using components (syringe, needle unit, plunger rod unit) that have not been steam - sterilized.

[0013] Regarding the test method of the present invention, a high-viscosity medium having a storage elastic modulus G' of about 84.5 Pa and a loss factor tanδ of about 0.48 can be selected. The viscosity can be measured using a plate-plate measurement system at 25 °C and an atmospheric pressure of 1013.25 hPa, particularly at a frequency of 1 Hz (for example, the rheometer MCR302 from Anton Paar). The measurement may be carried out, for example, by the method described in ISO standard 6721-10-2015-09. The syringe to be tested is completely filled with the high-viscosity medium as specified. Furthermore, the plunger rod unit is brought into the syringe at the start of the test method and is in operative connection with the syringe, but the syringe and the plunger rod unit are still in the starting position, i.e., the inoperative position, at the start of the test method. For the test method of the present invention, a standard plunger rod unit provided for each syringe to be tested can be used. For example, in the case of a syringe having an inner diameter of 5 mm, a standard plunger of the FM257 type (for example, from manufacturer Daetwyler) can be used.

[0014] In this test method, a force is applied vertically to the proximal end of the plunger rod unit via the test plunger of the testing machine. The test plunger is moved towards the distal end of the syringe at a constant test speed of 12.6 mm / min, and at this time, the force acting on the plunger rod unit is continuously increased up to a maximum of 420 N. The test plunger can be moved a maximum distance of 15 mm during the test. The acting force is detected by a force sensor having a sampling rate of 200 Hz. The test plunger continues to be moved or the acting force is increased until leakage and / or NPO occurs or the maximum force of 420 N is reached. If the measured force suddenly drops by at least 30%, the test is stopped, that is, leakage and / or NPO is recognized. The force acting at the time of occurrence of leakage and / or NPO is recorded and associated with the information on whether leakage and / or NPO is occurring at this force. In this case, the above-mentioned minimum NPO resistance and average NPO resistance can be determined from the recorded measurement results. The leakage investigated here is the leakage between the syringe and the needle unit that occurs based on the applied force and the pressure acting thereby. In other words, the force at which the highly viscous medium inconveniently flows out can be determined in the region of the luer lock joint between the syringe and the needle unit.

[0015] Mechanical failures to be avoided can occur especially due to NPO, leakage ( "leakage") between syringe components coupled to each other and / or breakage of the syringe. The inventors of the present invention have noticed that for using high-viscosity media and small cannula thicknesses of at least 31G, syringes with the above-described minimum NPO resistance are advantageous. A relatively small needle diameter or cannula diameter (e.g., greater than 30G) means less pain for the patient than a relatively large needle diameter or cannula diameter (e.g., the 27G diameter conventionally used with high-viscosity media), provided that at the same time, to supply a high-viscosity medium, a higher force needs to be applied than for a relatively large needle diameter or cannula diameter. The values according to the present invention described above for minimum NPO resistance take into account the finding that when male users use it as specified, the syringe or injection device can be operated with a maximum force (maximum finger force) of 95N on average. When female users use it as specified, the syringe or injection device can be operated with a maximum force (maximum finger force) of 64N on average. That is, the above-described minimum NPO resistance constitutes an optimal design of a syringe structure that is not overly dimensioned, despite ensuring reliable injection of high-viscosity media using very thin cannulas.

[0016] In one improvement, the syringe may have an average NPO resistance of at least 100N, preferably at least 105N, preferably at least 110N, more preferably at least 115N, and even more preferably at least 117N. In particular, the average NPO resistance may be from 100N to 120N, preferably from 105N to 120N, preferably from 110N to 120N, more preferably from 115N to 117N.

[0017] The average NPO resistance indicates the average value of the force that needs to be applied to the plunger rod unit in operative connection with the syringe, within the framework of the test method described above, to cause a needle drop. In order to obtain significant results regarding the average NPO resistance, at least 56 measurements of syringes of the same type and configuration are required in this case as well.

[0018] In one embodiment, the syringe may have a minimum leakage resistance of at least 100 N. Preferably, the syringe may have a minimum leakage resistance of more than 105 N, more preferably more than 117.5 N, and even more preferably more than 125 N. In particular, the syringe may have a minimum leakage resistance of 100 N to 130 N, preferably 105 N to 120 N, and preferably 110 N to 115 N.

[0019] In one improvement, the syringe may have an average leakage resistance of at least 115 N, preferably at least 120 N, preferably at least 123 N, more preferably at least 125 N, and even more preferably at least 127 N. In particular, the average leakage resistance may be 110 N to 135 N, preferably 115 N to 130 N, preferably 120 N to 130 N, and more preferably 125 N to 130 N.

[0020] The minimum leakage resistance (minimum non-tightness resistance) indicates the threshold value of the force that is applied to the plunger rod unit in operative connection with the syringe within the framework of the test method described above. The minimum leakage resistance is defined by the fact that less than 1.8% of the syringes tested below said threshold value exhibit non-tightness. In order to obtain significant results regarding the minimum leakage resistance, at least 56 measurements of syringes of the same type and configuration are required.

[0021] Furthermore, the average leakage resistance indicates the average value of the force that needs to be applied to the plunger rod unit, which is brought into the syringe within the framework of the above-described test method and is in operative connection with the syringe, in order to cause imperfection. In order to obtain significant results regarding the average leakage resistance, in this case as well, at least 56 measurements of syringes of the same type and configuration are required.

[0022] In one embodiment, the internal thread of the Luer lock connector may have an inner diameter of up to 7.15 mm or up to 7.12 mm. The inner diameter may preferably be at least 7.05 mm or at least 7.08 mm. In a preferred embodiment, the inner diameter is from 7.05 mm to 7.15 mm, preferably from 7.08 mm to 7.12 mm, and preferably at most 7.1 mm. This inner diameter represents the minimum inner diameter measured from the thread ridge of the sleeve-shaped end, i.e., from the thread ridge on one side to the thread ridge on the opposite side of the internal thread. An inner diameter having this dimension can have a positive influence on a sufficiently tight connection between the syringe and the needle unit coupled to the syringe, and thus can advantageously influence the adjustment of the NPO minimum resistance as well as the average NPO resistance. This also applies mutatis mutandis to the leakage minimum resistance and the average leakage resistance.

[0023] In one embodiment of the syringe, the internal thread may have a width of at least 0.44 mm or at least 0.46 mm at the ridge of the thread cross-section. Preferably, this width is at most 0.52 mm or at most 0.50 mm. In a preferred embodiment, the width may be from 0.44 mm to 0.52 mm, preferably from 0.46 mm to 0.50 mm, preferably 0.48 mm.

[0024] Additionally or alternatively thereto, the internal thread may have a width of at least 0.85 mm or at least 0.875 mm at the valley of the thread cross-section. Preferably, this width is at most 0.95 mm or at most 0.925 mm. In a preferred embodiment, the width may be from 0.85 mm to 0.95 mm, preferably from 0.875 mm to 0.925 mm, preferably 0.9 mm.

[0025] The female thread flanks may have an angle of 22.5° to 27.5°, in particular 24° to 26° or about 25°, on both sides of the thread cross-section. This angle may represent the angle formed between a line orthogonal to the longitudinal axis of the syringe and intersecting the thread cross-section and the side surface of the thread cross-section.

[0026] By forming the thread cross-section parameters according to the dimensions described above, the contact surface of the thread connection, i.e., between the female thread of the syringe and the complementary male thread of the attached needle unit, can be adapted. This can improve the Luer lock connection together with the attached needle unit and can have an advantageous effect on the adjustment of the NPO minimum resistance as well as the average NPO resistance. This also applies to the minimum leakage resistance and the average leakage resistance.

[0027] In one improvement, the distal end face of the outer cone, which has a relatively wide opening at the end of the outer cone, may project beyond the distal collar of the sleeve-like part by a distance of at least 2.1 mm or at least 2.2 mm. In one embodiment, the distance is at most 2.5 mm or at most 2.4 mm. In one preferred embodiment, the distal end face of the outer cone projects beyond the distal collar of the sleeve-like part by a distance of 2.1 mm to 2.5 mm, preferably 2.2 mm to 2.4 mm, preferably 2.3 mm. This structural adaptation can also have an advantageous effect on the adjustment of the NPO minimum resistance as well as the average NPO resistance. This also applies to the minimum leakage resistance and the average leakage resistance.

[0028] In one embodiment, the syringe may have an inner circumferential surface with an inclined surface at the proximal end, and the inclined surface tapers the inner circumferential surface when viewed in the direction from the proximal end to the distal end. In other words, in the region of the inclined surface, the inner circumferential surface may contract and extend in a conical shape when viewed in the direction towards the distal end. The inclined surface can facilitate the insertion of the plunger rod unit, or more precisely the plunger, into the syringe chamber. The inclined surface may have a length of at least 1.2 mm or at least 1.4 mm when viewed in the direction of the longitudinal axis of the syringe. In a plurality of embodiments, the length is at most 1.8 mm or at most 1.6 mm. In a preferred embodiment, the length is from 1.2 mm to 1.8 mm, preferably from 1.4 mm to 1.6 mm, and preferably about 1.5 mm. Additionally or alternatively, the inclined surface may form an angle of at least 13°, preferably at least 14°, preferably at least 15° with the longitudinal axis. By forming the inclined surface dimensioned in this way, the overall length of the syringe can be shortened compared to well-known syringes. This can have an advantageous effect on the ergonomics of the syringe or its handling by the user. Nevertheless, the inclined surface dimensioned in this way can ensure sufficient stability and sealing of the syringe (so-called Container Closure Integrity, CCI). That is, for example, in a fully filled non-operating syringe, it may be assumed that there is a gap of at least 9 mm to a maximum of 10 mm, or about 9.5 mm, between the proximal end of the syringe and the proximal end of the plunger of the plunger rod unit.

[0029] The syringe may have a maximum overall length of 80 mm and a maximum inner diameter of 5 mm in one embodiment, in which case a volume of at least 1 ml can be accommodated within the syringe. More precisely, a volume of at least 1 ml can be accommodated in total within the interior and within the chamber portion formed by the outer cone following the chamber. The overall length can be measured from the end face defining the proximal end of the syringe to the end face defining the distal end of the syringe, i.e., the end face of the outer cone. The inner diameter may be constant over the entire length of the chamber. For example, a total volume of 1073 ml may be accommodated within the interior and the chamber portion, thereby allowing for a 2% overfill in the chamber and a bubble enclosure section with a length of 1 mm. It should be noted that the accommodatable volume is not to be equated with the total volume formed by the entire chamber and chamber portion. In addition to the volume of the medium to be accommodated and the allowable tolerances regarding overfill and bubbles described above, the chamber must already additionally accommodate a part of the plunger rod unit in the non-operating position and be able to stably support it. For this purpose, the plunger of the plunger rod unit must already be located far enough away from the proximal end of the syringe in the non-operating position and be accommodated within the syringe. For example, a spacing of 9.5 mm may be provided between the proximal end of the syringe and the proximal end of the plunger of the plunger rod unit.

[0030] The syringe may preferably be formed and dimensioned in accordance with ISO standard 11040-6:2012-04-01.

[0031] The syringe may have a maximum overall length of 60 mm and a maximum inner diameter of 4.65 mm in another embodiment, in which case a volume of at least 0.5 ml can be accommodated in total within the interior and the chamber portion.

[0032] The syringe may have a maximum overall length of 71 mm and a maximum inner diameter of 5 mm in another embodiment, in which case a volume of at least 0.8 ml can be accommodated in total within the interior and the chamber portion.

[0033] The syringe may have a maximum overall length of 95 mm and a maximum inner diameter of 6.45 mm in another embodiment. In this case, a volume of at least 2.25 ml can be accommodated in the inner chamber and the chamber portion together.

[0034] The syringe may have a maximum overall length of 117 mm and a maximum inner diameter of 6.45 mm in another embodiment. In this case, a volume of at least 2.8 ml can be accommodated in the inner chamber and the chamber portion together.

[0035] The syringe may have a maximum overall length of 56 mm and a maximum inner diameter of 12.2 mm in another embodiment. In this case, a volume of at least 2.8 ml can be accommodated in the inner chamber and the chamber portion together.

[0036] The syringe may have a maximum overall length of 58 mm and a maximum inner diameter of 12.2 mm in another embodiment. In this case, a volume of at least 3.0 ml can be accommodated in the inner chamber and the chamber portion together.

[0037] The syringe may have a maximum overall length of 115 mm and a maximum inner diameter of 8.75 mm in another embodiment. In this case, a volume of at least 5 ml can be accommodated in the inner chamber and the chamber portion together.

[0038] The values described above may be the maximum dimensions or exact dimensions. A small inner diameter has a positive effect on administering highly viscous liquids by applying finger force to the syringe or injection device. However, at the same time, in order to ensure operability, it must also be noted that the overall length of the syringe, which also affects the overall length of the plunger rod unit used together, is not extremely large. Each of the above-described embodiments constitutes an embodiment showing an advantageous combination of overall length and inner diameter for various syringe volumes.

[0039] In one improvement, the syringe may have a wall thickness of at least 1.7 mm, preferably at least 1.8 mm, preferably at least 2.0 mm, and more preferably at least 2.2 mm in at least the region of the chamber. The formation of such a wall thickness can have a positive impact on the shape stability of the syringe during use, thereby reducing mechanical failures of the syringe. Each of the values shown forms a geometry optimized with respect to the ratio between the inner diameter and the outer diameter.

[0040] The syringe may have an outer diameter of, for example, 5 mm to 15 mm, particularly 7.5 mm to 12.5 mm, or 8.4 mm to 10 mm, particularly about 9.4 mm in the region of the chamber.

[0041] The syringe may be formed to have an extrusion force of less than 40 N when the standard plunger is moved toward the distal end in the chamber at 10 mm / min. The syringe may be formed to have an extrusion force of less than 75 N when the standard plunger is moved toward the distal end in the chamber at 50 mm / min. The syringe may be formed to have an extrusion force of less than 100 N when the standard plunger is moved toward the distal end in the chamber at 100 mm / min. Each of the above values relates to the supply of a high-viscosity medium having a storage modulus G’ of about 84.5 Pa and a loss factor tanδ of about 0.48. The viscosity can be measured using a plate-plate measurement system at 25 °C and an atmospheric pressure of 1013.25 hPa, particularly at a frequency of 1 Hz (e.g., Anton Paar's rheometer MCR302). The measurement may be performed, for example, by the method described in ISO standard 6721-10-2015-09. The extrusion force represents the force to cause the medium to flow out from the cannula of the needle unit coupled to the syringe. Usually, a high-viscosity medium requires a higher extrusion force than a low-viscosity medium. Each of the above values applies to a test unit having a cannula with a thickness of 30G and a length of 13 mm, i.e., a needle unit 30G×1 / 2, particularly the needle unit "TSK HYPODERMIC NEEDLE", Ref.: HPC-30013l-320, 30G×1 / 2. In this test method, since the cannula is open, the high-viscosity medium can flow out from the cannula. The needle unit has a thread (different from the needle unit with a tip) as a luer lock connector compatible member. For a high-viscosity medium, the force applied by the user required for such a syringe having a relatively small extrusion force is less, enabling improved metering accuracy. That is, such a syringe enables the use of a needle unit with a smaller thickness, i.e., a cannula with a thickness of 30G or more, despite the use of a high-viscosity medium.

[0042] In one embodiment, the syringe preferably has a modulus of elasticity of 2800 MPa to 3300 MPa, particularly 2900 MPa to 3200 MPa (1 mm / min, ISO 527 parts 1 and 2). ResinIt may be manufactured from the material. Resin The material may have a tensile strength in the range of 58 MPa to 65 MPa, particularly 60 MPa to 63 MPa (5 mm / min, ISO 527 Parts 1 and 2). Resin The material may have a water absorption rate of less than 0.01% (ISO 62). Furthermore Resin The material may have an indentation hardness of 180 - 195 N / mm 2 (30 - second value at a load of 961 N based on ISO 2039 Part 1). Resin The material may have a heat shape durability temperature of 120 - 180 °C (HDT / B 0.45 MPa, ISO 75 Parts 1 and 2). Resin The linear coefficient of thermal expansion of the material may be 6.0×10 -4 K -1 (ISO 11359 Parts 1 and 2). Resin The elongation at break of the material may be in the range of 2.5 - 2.7% (ISO 527 Parts 1 and 2). Resin The impact strength of the material may be about 15 kJ / m 2 (ISO 179 / 1eU) and / or the notched impact strength may be in the range of 1.6 kJ / m 2 - 1.8 kJ / m 2 (ISO 179 / 1eA).

[0043] In one improvement, the syringe may have a flange at its proximal end. The flange may be able to form a grip that supports the user's index finger and middle finger during the use of the syringe, or may be provided with such a grip.

[0044] Another aspect of the present invention relates to a syringe for injecting a high - viscosity medium, comprising a syringe and a plunger - rod unit in the form described above. The plunger - rod unit has a plunger rod and a plunger attached to the distal end of the plunger rod. The plunger is housed in the chamber through an opening formed at the proximal end of the syringe and is movably guided in the chamber. The plunger may have, for example, three sealing lips.

[0045] The syringe may have a highly viscous medium accommodated in the syringe chamber. In one embodiment, the highly viscous medium is characterized by a storage elastic modulus G' of at least 30 Pa and at most 150 Pa, in particular at least 50 Pa and at most 100 Pa, or at least 70 and at most 90 Pa. The loss factor tanδ may be from 0.2 to 0.8, in particular from 0.3 to 0.6 or from 0.4 to 0.5. The viscosity can be measured using a plate - plate measurement system at 25 °C and an atmospheric pressure of 1013.25 hPa, in particular at a frequency of 1 Hz (for example, the rheometer MCR302 from Anton Paar). The measurement may be carried out, for example, by the method described in ISO standard 6721 - 10 - 2015 - 09. For example, the syringe may have a hyaluronic acid filler and / or another cosmetic composition accommodated in the syringe chamber.

[0046] The syringe may have a gripping length of 6 cm to 12 cm, in particular 7.5 cm to 8 cm. The gripping length represents the length between the proximal end of the syringe and the proximal end of the plunger rod unit. The plunger rod unit may be provided with a grip at the proximal end.

[0047] Another aspect of the present invention relates to an injection device for injecting a highly viscous medium, having a syringe and a needle unit of the type described above. The needle unit has a needle base and a cannula, where the needle base has a luer - lock connector mating member complementary to the luer - lock connector of the syringe in order to form a luer - lock connection between the syringe and the needle unit. That is, the needle base has an inner cone complementary to the outer cone of the syringe and preferably a male thread complementary to the female thread of the syringe. Alternatively to the male thread, the needle base may have two pointed ends arranged on the outer peripheral surface of the needle base.

[0048] The needle unit may have a cannula with a thickness of at least 30G (gauge), preferably at least 31G, preferably at least 32G, preferably at least 33G, more preferably at least 34G, and even more preferably at least 35G. The cannula may have a length of at least 10mm, preferably at least 11mm, preferably at least 12mm, and more preferably at least 13mm. Alternatively, the cannula may have a length of 25mm or more.

[0049] The needle base of the needle unit may have an inner cone with a length along the longitudinal axis of the needle unit of 3mm to 7mm, preferably 5.5mm to 6.5mm, preferably about 6.1mm.

[0050] In particular, the injection device may have a needle unit "TSK HYPODERMIC NEEDLE" Ref.: HPC-30013l-320, 30G×1 / 2 or a needle unit comparable thereto.

[0051] Alternatively, the injection device may have a needle unit "TSK STERiJECT Hypodermic Needle" Ref.: PRC-30013l, 30G×1 / 2 or a needle unit comparable thereto.

[0052] In one embodiment, the syringe may be made of or contain cycloolefin copolymer (COC) and / or cycloolefin polymer (COP). Resin formed from the material.

[0053] In one improvement, Resin the material may contain one or more additives, in which case the additive may preferably be a coloring agent.

[0054] Although some aspects and features have only been described above and below with respect to the syringe, these aspects and features are correspondingly applicable to the syringe and / or injection device, and vice versa.

[0055] The present invention also relates to a therapeutic or cosmetic method comprising the step of administering a high-viscosity cosmetic formulation using the syringe, syringe described herein or injection device described herein. In one embodiment, the high-viscosity cosmetic formulation is characterized by a storage modulus G' of at least 30 Pa and at most 150 Pa, particularly at least 50 Pa and at most 100 Pa, or at least 70 and at most 90 Pa. The loss factor tanδ may be from 0.2 to 0.8, particularly from 0.3 to 0.6 or from 0.4 to 0.5. The viscosity can be measured using a plate-plate measurement system at 25 °C and an atmospheric pressure of 1013.25 hPa, particularly at a frequency of 1 Hz (e.g., a rheometer MCR302 from Anton Paar). The measurement may be carried out, for example, by the method described in ISO standard 6721-10-2015-09. Administration may include injection of the cosmetic formulation into the living body to be treated. Preferably, the formulation is administered into the administration site in the human body. The administration may be a subcutaneous injection. The administration site may be a person's face or part of a person.

Brief Description of the Drawings

[0056] The following examples of the present invention will be described in more detail with reference to the attached schematic diagrams.

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Mode for Carrying Out the Invention

[0057] The same reference numerals in the drawings indicate the same or similar members.

[0058] FIG. 1 shows various perspective views of an injection device 10 according to one embodiment of the present invention, shown as an exploded view and in an assembled state. The injection device 10 has a syringe (Syringe body) 12, a plunger rod unit (Piston rod unit) 14 and a needle unit 16.

[0059] The elongated syringe 12 is in the shape of a hollow cylinder and forms a chamber for accommodating a medium, particularly a highly viscous medium. The syringe 12 has a distal end 18 and a proximal end 20. The proximal end 20 has an opening through which the plunger rod unit 14 can be inserted into the chamber (see the right diagram in FIG. 1). A Luer lock connector 22, which will be described in detail with reference to FIG. 2, is formed at the distal end 18 of the syringe 12. The proximal end 20 of the syringe 12 is provided with a flange 24, and the flange 24 serves as a grip for supporting the user's index finger and middle finger when using the syringe 12.

[0060] The plunger rod unit 14 has a plunger rod 26 and a plunger 28. In this embodiment, the plunger 28 is made of an elastic material and has three seal lips. The plunger 28 is attached to the distal end of the plunger rod 26 and can be slidably guided within the chamber along the inner circumferential surface of the syringe 12 and be movable in the direction of the chamber longitudinal axis. The plunger rod unit 14 has a grip 30 at its proximal end, and a user can apply force to the injection device 10 via the grip 30 with the user's thumb.

[0061] The needle unit 16 has a needle base 32 and a cannula 34 in the form of a hollow needle. In the illustrated embodiment, the cannula 34 has a thickness of at least 30G and a length of 13 mm. However, cannulas with different dimensions may be used. The needle base 32 has a luer lock connector mating member 36, and the luer lock connector mating member 36 can form a tight luer lock connection with the luer lock connector 22 of the syringe 12, whereby the syringe 12 can be coupled to the needle unit 16. The luer lock connector mating member 36, or more precisely the needle base 32, in the illustrated embodiment has an inner cone and two pointed ends formed on the outer circumferential surface of the proximal end of the needle base 32. It is obvious that the needle base may be provided with male threads or a male threaded portion instead of the pointed ends in another embodiment. Such an embodiment with male threads can achieve a more reliable luer lock connection.

[0062] In order to keep the syringe 12 closed, for example, during transportation, the syringe 12 may be closed by the cap 38 shown in FIG. 1 in the region of the luer lock connector 22. This cap 38 is formed complementarily to the luer lock connector 22 of the syringe 12. After the cap 38 is removed from the syringe 12, the needle unit 16 is coupled to the syringe 12.

[0063] In the assembled state where the syringe 12, the plunger rod unit 14, and the needle unit 16 are structurally and operatively coupled to each other, the plunger 28 may be moved from the non-operating position to the operating position by being moved proximally from the proximal end portion 20 toward the distal end portion 18 within the chamber. Thereby, a highly viscous medium, such as hyaluronic acid, accommodated within the chamber can be injected under the skin surface of a patient through the cannula 34.

[0064] The syringe 12 is made of cycloolefin polymer (COP) or cycloolefin copolymer (COC) in the illustrated embodiment.

[0065] FIG. 2 shows an enlarged cross-sectional view of the luer lock connector 22 of the syringe 12. The luer lock connector 22 has an outer cone 40 with a relatively wide opening 42 for supplying a highly viscous medium accommodated within the chamber. As can be seen in FIGS. 1 and 2, the outer cone 40 protrudes beyond the distal end portion of the syringe 12 as a nozzle formed in a conical shape. The luer lock connector 22 further has a sleeve-like portion 44 with an internal thread 46. The outer cone 40 is surrounded by the sleeve-like portion 44, and in this case, the outer cone 40 and the sleeve-like portion 44 are coaxially arranged with respect to each other.

[0066] The internal thread 46 has a minimum inner diameter I1 of 7.1 mm measured from the thread ridge 50 of the internal thread 46 to the thread ridge 50' located on the opposite side. The maximum inner diameter I2 measured from the thread groove 54 of the internal thread 46 to the thread groove 54' located on the opposite side is 8.0 mm in the illustrated embodiment. The outer diameter A H of the sleeve-like portion 44 is 10.0 mm. Thus, the sleeve-like portion 44 has a wall thickness of 1 mm.

[0067] As can be seen from the detailed view of the thread cross-section of the internal thread 46 shown in FIGS. 2 and particularly FIG. 3, the internal thread 46 has a width B of 0.48 mm at the ridge 50 of the thread cross-section. Further, the internal thread 46 has a width B of 0.9 mm at the groove 54 of the thread cross-section. K has. Further, the internal thread 46 has a width B of 0.9 mm at the groove 54 of the thread cross-section.G It has. The female thread has angles α and β of 25° on both sides of the thread cross-section respectively. The thread cross-section formed with these dimensions helps to optimally fix the common contact surface with the complementary male thread of the attached needle unit. This can contribute to the accurate adjustment of the minimum NPO resistance, average NPO resistance, minimum leakage resistance and average leakage resistance.

[0068] The outer cone 40 has a distal end face 56 with a relatively wide opening 42 formed thereon. The distal end face 56 projects beyond the distal collar 58 of the sleeve-like portion 44 by a distance A of 2.3 mm when viewed in the direction of the longitudinal axis L of the syringe 12. Further, the distal end face 56 of the outer cone 40 is separated by a distance B of 3.1 mm from the lower side of the first complete thread cross-section on the side opposite to the end face 56. The outer cone 40 has a total cone length C of 8.9 mm in the illustrated embodiment.

[0069] In particular, parameter B of the thread cross-section shown in FIG. 3 K , B G , α and β, the minimum inner diameter I1 and / or the distance A may be provided with the said dimensions in a plurality of syringes with different volumes respectively, whereby the optimal values regarding the minimum NPO resistance, average NPO resistance, minimum leakage resistance and average leakage resistance of the syringe 12 can be achieved.

[0070] FIG. 4 shows a cross-sectional view of the syringe 12 with the plunger rod unit 14 accommodated therein. In this case, the plunger rod unit 14 is not shown in its entirety for reasons of visibility. The syringe 12 of the illustrated embodiment has a total length L of 80.0 mm SK It has. This total length L SK is composed of the length of the portion of the syringe forming the chamber and the total cone length C of the outer cone 40. The inner diameter I of the chamber K is 5 mm in the illustrated example. Thus, a total of 1073 mm is provided in the chamber of the syringe 12 and the subsequent chamber portion formed by the outer cone 40 3A medium having a volume V, particularly a highly viscous medium, can be accommodated. This accommodatable volume V is obtained from the consideration that the syringe 12 should supply a highly viscous medium with a volume of 1 ml and the resulting structural means. Further, the chamber needs to allow for a 2% overfill and a bubble enclosure with a length of 1 mm (refer to length s). In addition to the volume of the medium to be accommodated and the allowable errors regarding the above-mentioned overfill and bubbles, the chamber must also accommodate and stably support a part of the plunger rod unit in the non-operating position. For this purpose, it is desirable that the proximal end of the plunger 28 of the plunger rod unit 14 is already arranged at a distance u of 9.5 mm from the proximal end of the syringe 12 in the non-operating position. Further, in this non-operating position, the third (proximal) seal lip of the plunger 28 of the plunger rod unit 14 is also arranged at a distance o of 9.5 mm from the inclined surface 60 of the syringe 12. The plunger 28 has a length t of, for example, 6.9 mm.

[0071] The inclined surface 60 is formed on the inner peripheral surface of the proximal end 20 of the syringe 12. The inclined surface 60 tapers the inner peripheral surface of the syringe 12 when viewed in the direction from the proximal end 20 to the distal end 18.

[0072] In FIG. 5, the inclined surface 60 is shown enlarged. The inclined surface 60 has a length w of 1.5 mm when viewed in the direction of the longitudinal axis L of the syringe 12 and forms an angle γ of 15° with the longitudinal axis L. A radius R of 0.5 mm is provided in the transition region of the inclined surface 60 to the proximal end of the syringe 12.

[0073] The syringe 12 of the illustrated embodiment has a wall thickness of 2.2 mm in the region of the chamber, which serves for sufficient shape stability against breakage of the syringe.

[0074] FIG. 6 shows a diagram representing test results for a syringe according to the present invention, showing different measurement resistances of the syringe against NPO and leakage. The tests on which the basis is made were carried out using the syringe 12 shown in FIGS. 1 to 5. In the direction of the x-axis of the diagram, different measured values of the illustrated measured value column (56 individual measured values) are shown. The y-axis indicates the measured force applied to the syringe when the syringe failed due to NPO or leakage.

[0075] Regarding the test method, the syringe 12 to be tested was vertically arranged in a "TesT" company's "TesT 106.2kN" type universal testing machine and held in the region of the proximal end of the syringe 12. Before the start of the test, the syringe 12 to be tested was connected via a luer lock connector 22 to a needle unit "TSK STERiJECT Hypodermic Needle" Ref.: PRC-30013l, 30G×1 / 2 having an inner cone as a luer lock connector corresponding member and two tip portions arranged on the outer peripheral surface of the needle base of the needle unit. The luer lock connector 22 of the syringe 12 was screwed to the luer lock connector corresponding member of the needle unit with a torque of 12 Ncm. The cannula of the needle unit having a thickness of 30G and a length of 13 mm (30G×1 / 2) was flattened by a hammer before the test method was carried out, and thus closed. For this test method, after the needle unit was screwed onto the syringe, a dry luer lock joint was formed by filling the chamber with a high-viscosity medium. The test method was carried out using non-steam-sterilized components (syringe, needle unit, plunger rod unit). A high-viscosity placebo medium was used in this test method. This high-viscosity placebo medium had a storage elastic modulus G' of about 84.5 Pa and a loss factor tanδ of about 0.48. The viscosity was measured at 25°C and an atmospheric pressure of 1013.25 hPa using a plate-plate measurement system (for example, the rheometer MCR302 of Anton Paar). The frequency was 1 Hz. The measurement was carried out in accordance with ISO standard 6721-10-2015-09. The tested syringe 12 was the above material, that is, 1073 mm3 It was completely filled with a material having a volume of. In the plunger unit, a standard plunger of the FM257 type manufactured by Daetwyler was used.

[0076] A force was applied vertically to the proximal end of the plunger rod unit via the test plunger of the testing machine. The test plunger was moved toward the distal end of the syringe at a constant test speed of 12.6 mm / min, and at this time, the force acting on the plunger rod unit was continuously increased. A force of 420 N was adjusted as the maximum force, and the test was interrupted at this maximum force. The acting force was detected by a force sensor having a sampling rate of 200 Hz. The test plunger was continuously moved further until airtightness ("leakage") and / or NPO was recognized, that is, until the measured force suddenly decreased by at least 30%.

[0077] The force acting at the time of occurrence of airtightness and / or NPO was recorded for each measurement and written into the diagram shown in FIG. 6. The diagram shown in FIG. 6 represents the result of a measurement series including 56 measurement values. The result represented in the diagram shows that among the 56 measurement values, none of the syringes had a failure due to NPO or leakage at a force of less than 100 N. The number of 56 measurement executions guarantees that the minimum NPO resistance can be determined, and the minimum NPO resistance is defined by the fact that "needle drop" occurs in 1.8% or less of the syringes tested below the threshold value.

[0078] Since the maximum finger force for actually operating the syringe is on average 95 N, the syringe according to the present invention can avoid the occurrence of NPO and / or leakage.

[0079] FIG. 7 shows another diagram representing the test results regarding the extrusion force of the syringe according to the present invention compared with the extrusion force of a product well-known from the prior art. Different measurement values are shown in the direction of the x-axis of the diagram. The y-axis represents the measured extrusion force. This diagram shows the measurements using three different test speeds.

[0080] The syringe according to the embodiments shown in FIGS. 1 to 5 was compared with a "SCHOTT COC standard type" syringe with a filling volume of 1 ml (designation "TopPac 1ml long"). For the plunger unit, a standard plunger of the FM257 type from the manufacturer Daetwyler was used together with both syringes. As the needle unit, a needle unit "TSK HYPODERMIC NEEDLE", Ref.: HPC-30013l-320, 30G×1 / 2 with an open (not flattened) cannula having a thickness of 30G and a length of 13 mm was used together with both syringes. As the medium to be extruded, a high-viscosity medium was used. This high-viscosity medium had a storage modulus G' of about 84.5 Pa and a loss factor tanδ of about 0.48. The viscosity was measured at 25°C and an atmospheric pressure of 1013.25 hPa using a plate-plate measurement system (e.g., the rheometer MCR302 from Anton Paar). The frequency was 1 Hz. The measurement was carried out in accordance with ISO standard 6721-10-2015-09.

[0081] The tests were carried out by moving the plunger proximally to distally in the syringe at test speeds of 100 mm / min, 50 mm / min, and 10 mm / min. The test results show that at a test speed of 100 mm / min, the extrusion force of the syringe according to the present invention was reduced from 172.3 N to 94.9 N compared to the syringe according to the prior art. Further, the test results show that at a test speed of 50 mm / min, the extrusion force of the syringe according to the present invention was reduced from 136.4 N to 73.9 N compared to the syringe according to the prior art. Further, the test results show that at a test speed of 10 mm / min, the extrusion force of the syringe according to the present invention was reduced from 73.5 N to 38.3 N compared to the syringe according to the prior art.

[0082] Therefore, the ejection force of the syringe 12 according to the present invention is significantly less than that of known syringes. Therefore, the syringe according to the present invention requires less force from the user to dispense a highly viscous medium, thereby enabling improved metering accuracy. Therefore, the syringe according to the present invention allows the use of needle units with smaller cannula diameters, i.e., diameters of 30G or more, even when using highly viscous media. [Explanation of symbols]

[0083] 10 Injection device 12 syringes 14 Plunger rod unit 16 needle unit 18 distal end 20 proximal end 22 Luer lock connector 24 flange 26 Plunger rod 28 Plunger 30 Grip 32 Needle base 34 Cannula 36 Tip 38 Lid 40 outer cone 42 Aperture 44 Sleeve-like part 46 female thread 50,50' ridgeline 54,54' Valley 56 End face 58 Distal Collar 60 Slope L Longitudinal axis A. Distance B distance C Total length of cone I1 minimum inner diameter I2 Maximum Inner Diameter A H Outer diameter B K Width Ridgeline B G width valley α Angle in the cross section of the thread Another angle in the β thread cross-section Angle of the γ inclined plane I K Inner diameter V Accommodable volume L SK Overall length o Distance s Length of the bubble t Plunger length u Distance w Length of the inclined plane

Claims

1. A syringe body (12) for a syringe for injecting a high-viscosity medium, wherein the syringe body (12) has a hollow cylindrical structure and forms a chamber configured to accommodate the high-viscosity medium, and the syringe body (12) has a distal end portion (18), a proximal end portion (20) having an opening, a Luer lock connector (22) formed at the distal end portion (18), a needle base (32) coupled to the Luer lock connector (22) and carrying a cannula (34), and is provided with, a piston rod unit (14) is insertable into the chamber through the opening, the Luer lock connector (22) includes an outer cone (40) having a further opening (42) configured to supply the high-viscosity medium, and a sleeve-shaped portion (44) having a female thread (46), the syringe body (12) has an NPO minimum resistance of more than 90 N, the female thread (46) has a minimum inner diameter (I 1) of 7.05 mm to 7.15 mm, the female thread (46) has a width (BK) of 0.44 mm to 0.52 mm at a ridge line (50) of a thread cross-section of the female thread (46), and the female thread (46) has a width (BG) of 0.85 mm to 0.95 mm at a valley (54) of the thread cross-section, the needle base (32) has an inner chamber fluidly coupled to the further opening and a protrusion extending into the inner chamber, and the protrusion fluidly couples the cannula (34) to the inner chamber, syringe body (12).

2. The syringe body (12) has an average NPO resistance of at least 100 N, The syringe body (12) according to claim 1.

3. A distal end face (56) of the outer cone (40) protrudes beyond a distal collar (58) of the sleeve-shaped portion (44) by a distance (A) of 2.1 mm to 2.5 mm, The syringe body (12) according to claim 1.

4. The syringe body (12) further comprises an inner circumferential surface at the proximal end portion (20), and the inner circumferential surface has an inclined surface (60) that tapers the inner circumferential surface when viewed in the direction from the proximal end portion (20) to the distal end portion (18). The inclined surface (60) has a length (w) of 1.2 mm to 1.8 mm when viewed in the direction of the longitudinal axis (L) of the syringe body (12), and / or the inclined surface (60) forms an angle (γ) of at least 13° together with the longitudinal axis (L). The syringe body (12) according to claim 1.

5. The syringe body (12) has a maximum overall length (L) of 80 mm ＳＫ and an inner diameter (I) of up to 5 mm Ｋ and at least 1 ml of volume (V) can be accommodated within the syringe body (12). The syringe body (12) according to claim 1.

6. The syringe body (12) has a wall thickness of at least 1.7 mm at least in the region of the chamber. The syringe body (12) according to claim 1.

7. The syringe body (12) is manufactured from a resin material having an elastic modulus of 2800 MPa to 3300 MPa. The syringe body (12) according to claim 1.

8. The NPO minimum resistance of the syringe body (12) is 90 N to 105 N. The syringe body (12) according to claim 1.

9. An injection device (10) comprising a syringe body (12) and a piston rod unit (14), The syringe body (12) has a hollow cylindrical structure and forms a chamber configured to accommodate a high-viscosity medium. The syringe body (12) has a distal end portion (18), a proximal end portion (20) having an opening, a Luer lock connector (22) formed at the distal end portion (18), a needle unit (16) comprising a needle base (32) coupled to the Luer lock connector (22) and carrying a cannula (34), and is provided with,[[]]END]] The Luer lock connector (22) comprises an outer cone (40) having a further opening (42) configured to supply the high-viscosity medium, and a sleeve-shaped portion (44) having a female thread (46). The syringe body (12) has an NPO minimum resistance of more than 90 N. The female thread (46) has a minimum inner diameter (I1) of 7.05 mm to 7.15 mm. The female thread (46) has a width (BK) of 0.44 mm to 0.52 mm at the ridge line (50) of the thread cross-section of the female thread (46). The female thread (46) has a width (BG) of 0.85 mm to 0.95 mm at the valley (54) of the thread cross-section. The needle base (32) has an inner chamber fluidly coupled to the further opening and a protrusion extending into the inner chamber, the protrusion fluidly coupling the cannula (34) to the inner chamber, The piston rod unit (14) has a piston rod (26) and a piston (28) attached to the distal end of the piston rod (26), the piston (28) being received in the chamber through an opening in the proximal end (20) of the syringe body (12) and being movably guided in the chamber, Injector device (10).

10. The needle base (32) has a luer lock connector mating member (36) complementary to the luer lock connector (22) of the syringe body (12), the luer lock connector mating member (36) being configured to form a luer lock connection between the syringe body (12) and the needle unit (16). The injector device (10) according to claim 9.

11. The cannula (34) has a thickness of at least 31G, and / or the needle base (32) has an inner cone, the inner cone having a length of 3 mm to 7 mm along the longitudinal axis of the needle unit (16). The injector device (10) according to claim 10.

12. The high-viscosity medium comprises hyaluronic acid. The injector device (10) according to claim 11.

13. The injector device (10) further comprises a high-viscosity medium received in the chamber. The injector device (10) according to claim 9.

14. The syringe body (12) has an average NPO resistance of at least 100 N. The injector device (10) according to claim 9.

15. The minimum NPO resistance of the syringe body (12) is 90 N to 105 N. The injector device (10) according to claim 9.

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