JP2002000728A - Injection type liquid medicine injector having microscopic needle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an injection type liquid medicine injector having a microscopic needle capable of reducing pain at liquid medicine injecting time by injecting a liquid medicine in a very short time, reducing pressure for injecting the liquid medicine and reducing a diameter of a passage for making the liquid medicine to flow. SOLUTION: This liquid medicine injector 1 for injecting the liquid medicine from the skin is provided with a housing 3 for constituting an outer frame of the liquid medicine injector, a liquid medicine vessel 71 for housing the liquid medicine inside, the microscopic needle 101 having the length positioned in a living epidermal cell layer for penetrating the tip through a horny layer at using time or the boundary surface vicinity between an epidermal cell layer and a dermal layer, and a driving source for generating the pressure for injecting the liquid medicine in the liquid medicine vessel 71, and is characterized by injecting the liquid medicine in the liquid medicine vessel 71 from the skin via the microscopic needle 101.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drug solution injection device used for injecting a drug solution into skin, subcutaneous or intramuscular from human or animal skin, and more particularly to an injection type drug solution injection device.

[0002]

2. Description of the Related Art In recent years, a needle-free injector has been developed as a drug solution injection device capable of injecting a drug solution from a skin without using a needle. This needle-free injector sprays a drug solution while a nozzle provided at the tip of a drug solution container is applied to the skin surface, and penetrates the stratum corneum, living epidermal cell layer, and dermis layer to form a subcutaneous tissue layer or muscle. It is administered to the tissue layer. The advantages of needleless syringes are that, compared to needled syringes, there is less trauma during injection, less risk of cross-infection, and the problem of infection accidents and disposal due to puncture of used needles can be solved, Further, there is no puncture pain due to the needle, so that fear of the needle is wiped out. For this reason, a needle-free injector is used for daily injection of a drug solution by itself, such as insulin injection.

[0003] However, in the above-mentioned conventional needle-free injector, it is necessary to generate a high pressure by a driving source in order to eject a chemical solution. Therefore, the strength of the housing must be increased so as to withstand this pressure, and there is a problem that the weight increases and the bulk is increased. In addition, since there is a possibility that leakage of the drug solution may occur at the time of injecting the drug solution, the amount of the drug solution to be injected is not constant due to the habit of the user, which is not always suitable for accurate drug solution administration. Furthermore, in order for a drug solution to penetrate a relatively hard stratum corneum (dead cells on the surface of the epidermis) or a living epidermal cell layer in skin tissue, a considerably high pressure is required to inject the drug solution. Therefore, pain is likely to occur with this. In addition, an impulsive sound or vibration is generated with the generation of the high pressure, and there is a possibility that the user may feel fear.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and an object of the present invention is to reduce the pressure for injecting a chemical solution, It is an object of the present invention to provide an injection-type drug solution injector that can reduce the diameter of a flow path for flowing a drug solution, thereby reducing pain at the time of drug solution injection.

[0005]

The object of the present invention is achieved by the following means.

(1) A drug solution injection device for injecting a drug solution from the skin, wherein the tip of a microneedle provided at the end of the device is
In the epidermal cell layer alive beyond the stratum corneum, or in a state where it is located near the boundary between the epidermal cell layer and the dermis layer, by a driving source that generates pressure, ejects a drug solution and passes through the microneedle A drug solution injector for injecting from the skin.

(2) A drug solution injection device for injecting a drug solution from the skin, comprising a housing constituting an outer frame of the drug solution injection device, a drug solution container for containing the drug solution therein, and a tip which penetrates the stratum corneum when used. A microneedle having a length located in the epidermis cell layer or near the boundary between the epidermis cell layer and the dermis layer, and a drive source for generating pressure for injecting a drug solution in the drug solution container. And, the chemical solution in the chemical solution container,
A drug solution injection device, which is injected from the skin via the microneedle.

(3) Injection time for one injection of the chemical is 1
In less than a second, the injection amount per one time of the drug solution is 0.01 to 2 m
(1) The liquid injector according to (1) or (2), wherein

(4) The microneedle according to the above (1) or (2), wherein the microneedle has a needle part whose length that can be punctured into the skin is 0.02 to 1.0 mm. Liquid injector.

(5) The microneedle is provided with a hollow needle portion having a flow path for flowing a drug solution formed therein, which is pierced into the skin, and a through-hole communicating with the flow path. The liquid injector according to the above (1) or (2), further comprising a base supporting the needle.

(6) The chemical liquid injector according to the above (5), wherein the flow path of the needle portion is formed so that the cross-sectional area decreases as approaching the tip.

(7) The microneedle has a solid needle portion to be punctured into the skin, a base portion provided with a through hole and supporting the needle portion, and has one outer surface of the needle portion. A flow path for flowing a chemical solution is formed by notching a portion to communicate with a through hole of the base portion or by providing a through hole of the base portion near the base of the needle portion. The liquid injector according to the above (1) or (2).

(8) The chemical injection device according to the above (5) or (7), wherein the through-hole of the base portion is formed so that a cross-sectional area decreases as approaching a tip.

(9) The microneedle has an ejection port for ejecting a chemical solution, and the diameter of the ejection port is 0.01-0.
(1) or (2) above, wherein the distance is 5 mm.
3. The chemical liquid injector according to claim 1.

(10) The liquid injector according to the above (1) or (2), wherein the microneedle has a plurality of needles pierced into the skin.

(11) The microneedle is formed of any material selected from metals, ceramics, plastics, and composite materials composed of two or more materials so as to withstand the injection pressure of a chemical solution. The drug solution injector according to the above (1) or (2), wherein

(12) The chemical liquid injector according to the above (1) or (2), wherein the drive source is one selected from a spring, gas, rubber, and a solenoid valve.

(13) The chemical liquid injector according to the above (1) or (2), wherein the pressure for injecting the chemical liquid is 11.8 MPa or less.

(14) The liquid injector according to (2), wherein the microneedle is detachably provided to the liquid container.

[0020]

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1A and 1B are views showing a chemical liquid injector according to a first embodiment of the present invention, wherein FIG. 1A is a plan view and FIG.
FIG. 2 is a side view, and FIG. 2 is a horizontal sectional view of the injector body.

As shown in FIG. 1, the liquid injector 1 is composed of an injector body 2 and a cartridge 7, and when the start button 55 is pressed, the liquid is injected from the tip of the cartridge 7. This is an injection-type drug solution injection device provided with a microneedle 101 for injecting the drug from the skin.

As shown in FIG. 2, the injector main body 2 is supported by a housing 3 constituting an outer frame of the chemical liquid injector 1 and a bearing 31 provided in the housing 3, and extends in the longitudinal direction of the housing 3. It has a reciprocally movable plunger 4 and a tension spring 6 whose front end (left end in the drawing) is connected to the housing 3 and whose rear end (right end in the drawing) is connected to the plunger 4. . The plunger 4 is inserted into the tension spring 6.

As shown in FIG. 1B, the housing 3 has a pair of upper and lower housing elements 3a and 3a.
b, and is formed of, for example, plastic or the like. One of the two housing elements 3a, 3b is formed with a not-shown claw, and the other is formed with an unshown engagement hole with which the claw is engaged. Housing 3
Is assembled by the joining ends of the housing elements 3a and 3b abutting each other and the above-mentioned claw portions being engaged with the engagement holes. A boss portion 32 is provided on the distal end side of the housing 3, and a female screw portion 33 for screwing a chemical solution container 71 described later is formed on the inner surface of the boss portion 32.

The plunger 4 has a rod shape, and a ring-shaped projection 56 for attaching a gasket 81 to be described later is formed at the tip. Further, a flange portion 57 is formed at an intermediate portion of the plunger 4. The plunger 4 is formed of a material having excellent pressure resistance and impact resistance, and examples of the material used include plastic and metal.

A stopper 62 is provided between the boss 32 of the housing 3 and the flange 57 of the plunger 4 while being held slidably by the guide 38. A through hole 63 is formed along the axis of the stopper 62, and the plunger 4 is inserted into the through hole 63 with a predetermined gap. Therefore, when the plunger 4 moves forward (to the left in the drawing), the flange portion 57 of the plunger 4 presses the stopper 62, but the stopper 6
2 comes to abut against the end face of the boss 32 of the housing 3 and is stopped. As described above, the stopper 62 is attached to ensure the safety so that the plunger 4 does not protrude forward when the cartridge unit 7 is not mounted and when the liquid medicine administration is completed.

At the rear end of the plunger 4, a cushioning member 4
1 is attached, and a spring fixing portion 45 to which the rear end of the tension spring 6 is fixed is attached to the rear end of the cushioning member 41. Therefore, the rear end of the tension spring 6 is connected to the plunger 4 via the spring fixing portion 45 and the cushioning member 41.

The cushioning member 41 has a function of reducing an impact generated when the tension spring 6 contracts from a tensioned state. That is, the cushioning member 41 has a structure that does not give a shock to the whole liquid injector 1 by absorbing kinetic energy when the tension spring 6 contracts. This buffer member 4
1 includes a compression spring 42 and a holder 43 for accommodating the compression spring 42 therein and holding the compression spring 42 between the plunger 4 and the spring fixing portion 45. Note that the cushioning member 41 is not limited to the above configuration, and for example, rubber, an air suspension, a hydraulic damper, or the like can be used.

FIG. 3 is a view showing a spring fixing portion.
(A) is a plan view, (B) is a side view, and (C) is a left side view.

As shown in FIG. 3, the spring fixing portion 45 includes
A pair of locking portions 4 for locking the wire at the rear end of the tension spring 6
6, 46 are provided. Further, the spring fixing portion 45 is formed with a concave groove 47 into which a distal end portion of a latch member 51 described later enters and engages. Further, the spring fixing part 4
5 includes a pair of slide buttons 49 for sliding the spring fixing portion 45 rearward (rightward in the figure) during use.
Is provided. The slide button 49 is located in the opening 37 opened in the housing 3 and is exposed outside the housing 3. The spring fixing portion 45 has a pair of guides for guiding the distal end of the latch member 51 to the concave groove 47 when the plunger 4 and the spring fixing portion 45 are retracted against the tension of the tension spring 6. A groove 48 is formed.

FIG. 4 is a sectional view taken along line IV in FIG. As shown in FIG. 4, the latch member 51 is
3 is held in a substantially U-shaped groove 54 formed at the end. The arm 53 is fixed to a pin 52 rotatably supported by the housing 3. The arm 53 includes a leaf spring 5
As a result, the groove 54 holding the latch member 51 is constantly urged in the direction of turning inward. A start button 55 is fixed to an end of the arm 53 opposite to the groove 54. This start button 55 is
Is located in the opening 34 opened at the same time.

The housing 3 includes a latch member 51.
A concave portion 35 is formed in which the head is reciprocally accommodated. Thereby, the latch member 51 is connected to the plunger 4.
It is possible to advance and retreat toward the axis of. Therefore, when the start button 55 is pressed, the latch member 51 can be moved toward the bottom of the recess 35, that is, outwardly via the arm 52.

As the tension spring 6, a spring having an initial tension is preferably used. A tension spring with initial tension is
It is a tension spring in which an internal stress acting to keep the spring in close contact in a natural state is generated. Therefore, the tension spring 6 of the present embodiment does not substantially expand even if a tensile force is applied until the internal stress is released. The force required to extend the tension spring 6 by applying a tensile force corresponds to the initial tension.

As shown in FIG. 5, the wire at the distal end of the tension spring 6 is locked at the peripheral edge of the hole 61 of the retainer 36.
The retainer 36 is made of a plate having a thickness of about 1 to 2 mm. The retainer 36 is fitted in a locking groove 39 having a predetermined groove width provided in the housing 3, whereby the distal end of the tension spring 6 is connected to the housing 3.

The tension spring 6 is mounted in the housing 3 in close contact. Therefore, before the use of the liquid injector 1, the urging force of the tension spring 6 does not act to the outside. This eliminates the need for the housing of the injector body to constantly maintain the force generated when the spring is pre-compressed in order to ensure the minimum injection output when a compression spring is used, for example.

FIG. 6 is a side view of the cartridge section, and FIG.
FIG. 3 is a sectional view of a cartridge unit. As shown in FIGS. 6 and 7, the cartridge unit 7 includes a chemical solution container 71 that stores a chemical solution therein, and a gasket 81 that is inserted into the chemical solution container 71 in advance. The chemical solution container 7
The gasket 1 and the gasket 81 may be prepared separately at first.

The chemical solution container 71 has a cylindrical container main body 72 and a microneedle 1 provided on the distal end side of the container main body 72.
01. The chemical solution container 71 preferably includes a protective cap (not shown) that covers the microneedle 101.

The housing 3 has a housing 3
A male screw part 75 screwed to the female screw part 33 is formed. In the present embodiment, as will be described later, the injection amount of the chemical can be adjusted by the screwing amount of the container main body 72 into the boss portion 32 at the time of injection of the chemical.
On the outer peripheral surface on the rear end side of the container main body 72, for example, at a plurality of positions in the circumferential direction, flat portions 76 located inward from the outer peripheral surface are formed. Is provided with a scale 77 for grasping. Further, a projection 78 for lightly locking an adapter 91 (see FIG. 13) used when filling the container main body 72 with a chemical solution is provided on the outer peripheral surface near the distal end side of the container main body 72.

The chemical solution container 71 is formed of a material that can withstand a predetermined high injection pressure of the chemical solution, and the material used is, for example, glass, plastic, metal, or a composite material of two or more materials. It is desirable to select from among them. However, even a material having low pressure resistance can be used by coating the periphery of the container with a reinforcing material such as metal. In addition, it is preferable to form all or a part of the chemical solution container 71 from a transparent material because the chemical solution contained in the inside can be visually checked.

The gasket 81 is in close contact with the inner surface of the container body 72, and serves to seal the liquid medicine from leaking backward. The plunger 4 is provided inside the gasket 81.
A hole 82 into which the tip of the plunger 4 is inserted is formed.
3 are formed. As a material of the gasket 81, for example, rubber, elastomer, or the like is used.

FIG. 8 is an enlarged view showing a minute needle.
(A) is a view from the front, (B) is a side view, and FIG.
FIG. 4 is a cross-sectional view showing a state where the needle portion of the microneedle is punctured into the skin.

As shown in FIG. 8, the microneedle 101 has a needle part 110 punctured into the skin and a base part 120 supporting the needle part 110.

As shown in FIG. 9, the needle portion 110 of the microneedle 101 is, as shown in FIG. 9, in the epidermis cell layer 132 whose tip penetrates the stratum corneum 131, or at the interface between the epidermis cell layer 132 and the dermis layer 133. It has a length located in the vicinity of 141 (immediately below the skin). Generally, the thickness of the stratum corneum 131
It varies depending on gender, age, body part, living environment, etc., and is not constant.
0 μm. The thickness of the living epidermal cell layer 132 is not constant due to various factors, but is usually 30 to 100 μm in the upper arm of a human. The dermis layer 1
The thickness of 33 is not constant, but is usually 1 to 3 mm. Therefore, specifically, the length of the portion of the needle portion 110 to be punctured into the skin is preferably 0.02 to 1.0 m
m, more preferably 0.02 to 0.2 mm. Note that the entire length of the needle portion 110 (the entire length including the portion that does not enter the skin) is not pushed into the root portion of the needle portion 110 (the surface of the base portion 120 facing the skin) due to the flexibility of the skin. 0.1
About 3 mm, preferably 0.5 to 1.5 m
m is more preferable.

The needle portion 110 has a substantially conical shape as shown in the figure. However, the shape of the needle portion 110 is not particularly limited, and is arbitrary as long as it can puncture the skin and inject the drug solution. For example, the needle portion 110 may have a pyramid shape, or may have only a tip of a cylinder or prism in a conical shape or a pyramid shape, or may be processed into a shape in which the tip portion is obliquely cut.

As shown in FIG. 8, the needle portion 110 of the microneedle 101 is a hollow needle portion in which a flow path 111 for flowing a chemical solution is formed. The flow path 111 has a constant cross-sectional area and has a linear shape. The diameter of the chemical liquid ejection port located at the tip of the flow path 111 is, for example, 0.01 to 0.5 mm. Here, when using the liquid injector 1 for thick skin or hard skin, use a device having a different diameter of the spout due to a difference in the properties of the skin, such as using a device having a larger spout diameter. be able to.

The flow path 111 of the needle part 110 may be formed so that its cross-sectional area becomes smaller as it approaches the tip. By doing so, the injection pressure of the chemical can be increased. Further, a through-hole 121 for flowing a chemical solution is formed in the base portion 120, and the through-hole 121 communicates with the flow path 111. The through hole 1 of the base 120
21 may also be formed so that the cross-sectional area decreases as approaching the tip from the viewpoint of increasing the injection pressure of the chemical solution.

FIGS. 10A and 10B are enlarged views showing a modification of the microneedle, wherein FIG. 10A is a view from the front and FIG. 10B is a side view.

The microneedle 101a shown in FIG. 10 has a solid needle part 110a pierced into the skin and a base part 120a supporting the needle part 110a, and a part of the outer surface of the needle part 110a. Is cut out to form a flow path 111a for flowing a chemical solution. In this case, the flow path 111a
Has a groove shape. Further, a through-hole 121a for flowing a chemical solution is formed in the base portion 120a, and the through-hole 121a communicates with the flow path 111a. In FIG. 10, only one channel 111a is formed, but a plurality of channels may be formed on the outer surface of the needle portion 110a.
Further, without forming the flow path 111a on the outer surface of the needle part 110a, by providing one or more through holes near the base of the needle part of the base part, a flow path for flowing the chemical solution is formed. Is also good. In this case, when the chemical solution is ejected from a flow path which is a through hole provided in the base portion, it is injected into the skin along the outer surface of the needle portion.

The through-hole 121 of the base 120 communicates with the inside of the container main body 72 of the chemical solution container 71.
Are integrally formed on the front end surface of the container body 72 in advance. However, the base portion 120 is bonded or welded.
May be fixed to the container body 72. Furthermore, the microneedle 1
01 may be detachably provided to the container main body 72 of the chemical liquid container 71 by, for example, screwing. However,
In this case, it is necessary to have a strength capable of withstanding the injection pressure of the chemical solution, and it is necessary to secure leakage resistance by providing a seal member or the like.

The microneedles 101 are formed of a material that can withstand a predetermined high injection pressure of a chemical solution. Examples of the material used include metals such as stainless steel and titanium, plastics such as ceramic, polycarbonate, and polyimide; It is selected from among composite materials composed of two or more materials. The microneedle 101 can be manufactured using a known method such as lithography or another fine processing method, electrodeposition molding, plastic molding, metal molding (MIM or the like), electric discharge machining, etching molding, or laser machining. it can.

The microneedles 101, shown in FIGS.
101a has only one needle portion 110, 110a, respectively, but the microneedle of the present invention is not limited to this, and may have a plurality of needle portions. By doing so, the injection amount of the chemical solution can be increased. In addition, since the liquid medicine can be injected from a plurality of needle portions, the diameter of each needle portion can be reduced, and pain can be reduced. Further, since the drug solution is dispersed and injected, a rapid effect of the drug can be expected.

Next, the operation of the thus configured chemical liquid injector will be described.

FIG. 11 is a horizontal sectional view of the injector main body showing a state in which the plunger is moved backward by a predetermined distance and held while resisting the tension of the tension spring. FIG. 12 is an injector main body in the state of FIG. FIG. 13 is a cross-sectional view showing an adapter and a vial filled with a chemical solution, and FIG. 14 is a diagram showing a state in which the chemical portion is screwed into the chemical solution container. FIG. 15 is a cross-sectional view showing a state of filling, FIG. 15 is a horizontal cross-sectional view showing a state before the medicinal solution administration of the medicinal solution injector, FIG. 16 is a horizontal cross-sectional view showing a state after medicinal solution administration of the medicinal solution injector, and FIG. It is a figure showing the relation between the deflection of a tension spring, and the ejection power of a medical fluid.

When the liquid injector 1 is used, first, as shown in FIG. 11, the slide button 49 provided on the spring fixing portion 45 of the injector main body 2 is slid backward, and the latch member is moved. 51 to the spring fixing portion 4
5 is engaged with the groove 47. This allows
While the tension spring 6 is pulled from the close contact state (Q1 in FIG. 17), the plunger 4 is held backward (Q2 in FIG. 17) moved a predetermined distance. The stopper 6
2 does not move as the plunger 4 moves rearward.

Then, as shown in FIG. 12, the cartridge part 7 is screwed into the boss part 32 formed on the housing 3 of the injector main body 2 to the full extent. Thereby, the container body 7
Inside 2, the gasket 81 is mounted on the tip of the plunger 4. At the same time, the stopper 62 is pushed rearward by the cartridge section 7 and comes into contact with the inner end face of the guide section 38.

On the other hand, as shown in FIG. 13, an adapter 91 is attached to a vial 85 filled with the chemical solution 8. The adapter 91 includes a needle portion 92 in which a passage 93 along the axis is formed. The tip of the needle portion 92 reaches the chemical solution 8 through the rubber stopper 86 of the vial 85.

The drug solution used in the drug solution injector 1 is a solution, gel or suspension containing a drug. The drug that can be used is not substantially limited as long as it is not a drug that is not suitable for transdermal administration. The main drugs include, for example, antibacterial drugs, antiviral drugs, vaccines, antitumor drugs, immunosuppressants, steroid drugs, antiinflammatory drugs, antirheumatic drugs, arthritis drugs, antihistamine drugs, antiallergic drugs, and diabetes treatment Drugs, hormones, bone and calcium metabolism drugs, vitamins,
Blood products, hematopoietic drugs, antithrombotic drugs, antihyperlipidemic drugs, antiarrhythmic drugs, vasodilators, prostaglandins, calcium antagonists, ACE inhibitors, β-blockers, antihypertensive drugs, diuretics, xanthine derivatives, β Agonists, antiasthmatics, antitussives, expectorants, anticholinergics, antipyretics, gastric digestives, antiulcers, laxatives, sleeping pills, sedatives, analgesics, antipyretics, colds, antiepileptics, anti Psychotic drugs, antidepressants, anxiolytics, central nervous stimulants, parasympathomimetics, sympathomimetics, antiemetics, central stimulants, antiparkinsonian drugs, muscle relaxants, antispasmodics, anesthetics, antipruritics , An anti-migraine drug, a diagnostic drug, an oligonucleotide, a gene drug, and the like. However, the drug is preferably a peptide, a protein, a polysaccharide, an oligonucleotide, a DNA, or the like, which is ineffective or attenuated by oral administration.

Next, as shown in FIG. 14, when the cartridge section 7 of the drug solution injector 1 is inserted into the adapter 91, the micro needle 101 of the drug solution container 71 comes into contact with the seal member 95 of the adapter 91, and The protrusion 78 of the container 71 is a minute protrusion 94 formed on the inner surface of the adapter 91.
Being over, is locked lightly. In this state, the cartridge unit 7 is turned in a direction opposite to when the cartridge unit 7 is screwed into the boss unit 32. As a result, only the liquid medicine container 71 of the cartridge unit 7 moves forward with the gasket 81 fixed to the plunger 4, so that a negative pressure is generated in the liquid medicine container 71. Due to this negative pressure, the chemical solution 8 in the vial 85 is sucked up, passes through the passage 93, and enters the chemical solution container 71. Further, with the movement of the cartridge section 7, the stopper 62 separates from the guide section 38 and can move forward.

A rubber anti-rotation member 96 is attached to the inner surface of the adapter 91 on the side where the cartridge section 7 is inserted. The rotation preventing member 96 can rotate the chemical solution container 71 and the adapter 91 together when the cartridge unit 7 is turned at the time of filling the chemical solution 8, so that the chemical solution 8 can be rotated.
Is sucked into the chemical solution container 71 satisfactorily.

At this time, the required amount of the chemical solution 8 can be drawn into the chemical solution container 71 by using the scale 77 provided on the chemical solution container 71. A predetermined amount of the drug solution 8 is
Is filled, the cartridge unit 7 is pulled out of the adapter 91 and removed.

In this way, as shown in FIG. 15, in a state where the liquid injector 1 is ready for the liquid injection, the tip of the cartridge unit 7 is pressed against the skin surface of the liquid injection site.
Press the start button 55. Thereby, the latch member 5
1 comes out of the concave groove 47 of the spring fixing portion 45, and the tension spring 6 held in a state of being pulled from the close contact state contracts.
Since the latch mechanism for engaging and disengaging the latch member 51 and the concave groove 47 is provided in this manner, the operation by the user at the time of injecting the chemical solution is facilitated.

The plunger 4 is moved forward by the force of the tension spring 6 contracting. Thereby, as shown in FIG. 16, the gasket 81
Is pressed, and the chemical solution is ejected from the ejection port of the microneedle 101 and injected into the body. Then, the stopper 62 comes into contact with the rear end of the cartridge portion 7 and the flange portion 57 of the plunger 4 comes into contact with the rear end of the stopper 62, whereby the plunger 4 is stopped. At this time, in order to inject the drug solution into the body, an impact is generated when the tension spring 6 contracts from the tensioned state, but the impact is reduced by the buffer member 41.

Here, the latch member 51 is connected to the spring fixing portion 45.
17, the tension spring 6 is in the close contact state Q1 where the amount of deflection of the spring is zero, as shown in FIG.
From the tension Q where the amount of deflection of the spring is W2
2 and the maximum ejection force F2 of the chemical is determined. on the other hand,
When the latch member 51 is disengaged from the groove 47 of the spring fixing portion 45, the tension spring 6 is moved from the tensioned state Q2 where the amount of deflection of the spring is W2 to the close contact state Q1 where the amount of deflection of the spring is zero. It can be set to shrink, and the minimum ejection force F1 of the chemical can be secured.

As described above, in this embodiment, the tension spring 6 having the initial tension is pulled from the close contact state during use, and the chemical solution is ejected by utilizing the contraction force of the tension spring 6. Therefore, it is not necessary to adopt a strong structure for always holding the force generated when the spring is contracted in advance as in the case of using a compression spring, so that the weight of the entire apparatus is reduced.

Further, as shown in FIG. 17, since the deflection of the tension spring 6 during the injection of the chemical solution changes from W2 to zero in the close contact state, a large amount of change in the deflection of the spring during the injection of the chemical solution is ensured. can do. Therefore, the stroke length of the plunger 4 can be increased, and a larger amount of the chemical can be ejected.
Further, in the case where the tension spring 6 is used, at the end of the injection of the chemical solution, the spring can be set by the screwing amount of the cartridge so that the spring comes into close contact, so that the impact force applied to the stopper can be reduced. Further, by providing the buffer member 41, the impact at the end of the injection of the chemical solution can be further reduced, and the impact force and the impact sound applied to the user and the like can be reduced.

According to the present embodiment, in particular, by pressing the tip of the cartridge section 7 against the skin surface,
The tip of the needle part 110 can be positioned in the living epidermal cell layer 132 penetrating the stratum corneum 131 or near the boundary surface 141 between the epidermal cell layer 132 and the dermis layer 133 (immediately below the epidermis). Here, since there is no free nerve ending related to pain in the stratum corneum 131 and the living epidermal cell layer 132, even if the needle portion 110 of the microneedle 101 is punctured into the skin, almost no pain is felt. Never.

On the other hand, the stratum corneum 131 is a dead cell without nucleus filled with keratin or fibrous protein, and is formed most robustly in skin tissue, and protects the living body from invasion of foreign matter from outside. Barriers to doing so. For this reason, the conventional needle-free injector must generate a considerably high pressure so that the injected drug solution penetrates the solid stratum corneum 131 and the living epidermis cell layer 132 in which the cells are dense. Did not. On the other hand, when injecting a drug solution using the microneedle 101, the drug solution injector 1 of the present embodiment has the tip of the needle portion 110 penetrating through the stratum corneum 131 and living in the epidermal cell layer 132 or the epidermal cell layer. 132 and dermis 13
Since the puncture is performed until it is located near the boundary 141 with the liquid medicine 3, the liquid medicine that has been injected does not require a high pressure for piercing the skin as in a conventional needle-free injector, and is relatively low in pressure. Can be injected. In particular,
The pressure generated by the driving source is lower than the pressure used in the conventional needleless syringe, for example, 11.8 MPa.
(120 kgf / cm ² ), preferably 5.9 MPa
(60 kgf / cm ² ), more preferably 4.4 MPa
(45 kgf / cm ² ).

The injection time of a chemical solution by the chemical solution injector 1 of the present invention per one time is equal to that of a conventional needleless syringe (0.2 times).
(Less than 5 seconds, in most cases less than 0.1 second) or longer. However, the injection time per one injection of the drug solution is preferably about 1 second or less, and may be set, for example, between 0.25 and 1 second. In addition, the injection amount per one injection of the drug solution can be set to be equal to a single injection amount of a normal injection (in most cases, 1 ml or less), or can be set between 0.01 and 2 ml.

Further, since the injection pressure of the chemical solution can be reduced as described above, the dermal layer 133 that passes when the chemical solution flows to the subcutaneous tissue layer 134 or the muscular tissue layer 135 is reduced accordingly. The stimulation of the neural network associated with the existing pain is weakened and the pain is further reduced. In addition, the durability of members such as the housing 3 and the chemical solution container 71 that require pressure resistance and impact resistance is relatively improved due to a decrease in the injection pressure of the chemical solution. Alternatively, the improvement in durability can contribute to weight reduction and size reduction of members constituting the device such as the housing 3 and the chemical solution container 71.

Further, the fact that the chemical can be injected and injected at a lower pressure means that the diameter of the flow path for flowing the chemical can be reduced if the driving sources for generating the pressure are the same. Make it possible. This is because, generally, when the cross-sectional area of the injection hole for ejecting the chemical solution is reduced, the injection pressure tends to decrease. Therefore, since the medicinal solution is injected with a narrower flow path diameter, the contact area of the medicinal solution with respect to the nerve network related to pain can be reduced, and the stimulation to the neural network is reduced, thereby suppressing the occurrence of pain. For example, mosquitoes almost completely painlessly pierce their own needles into the skin layer and suck blood, but the saliva components of the mosquito have not been found to have any particular anti-pain action. It is said that the reason why mosquitoes pierce the skin layer is painless is the small diameter of the needle (50-100 μm) (Kouichi Saito, Sogaku Kikaku, Vol. 46, 2412-2413,
1997).

FIG. 18A is a perspective view of the injector main body of the injection type chemical injection device according to the second embodiment of the present invention, and FIG. 18B is an injection device shown in FIG. 18A. FIG. 19 is a plan view of a state in which a cover of a container main body is removed, FIG. 19 is a cross-sectional view of an injection-type drug solution injection device according to the present embodiment, FIG. 20 is a perspective view near the tip of a plunger, and FIG. 22A to 22D are cross-sectional views of the gasket and the check valve. Hereinafter, the second embodiment will be described, focusing on the differences from the first embodiment, and omitting common parts as appropriate.

As shown in FIGS. 18 and 19, the injection type chemical liquid injection device 201 has an injector body 202. The injector body 202 includes a housing 203 having a lower case 203a and a cover 203b.
The cover 203b is attached to the lower case 203a by a hinge 203c so as to be freely opened and closed. Note that FIG.
Reference numeral 203d in (B) denotes an inner cover that covers a drive mechanism such as a compression spring 207 and a plunger 204 described later.

As shown in FIG. 19, a plunger 204 is provided on the injector body 202 so as to be movable in the axial direction, and a latch holding portion 205 is provided behind the plunger 204 (to the right in FIG. 19). Is provided. The plunger 204 is formed of a material having excellent pressure resistance and impact resistance, and examples of the material used include plastic and metal.

The latch holding portion 205 of the plunger 204
A guide groove 205a for guiding the tip of the latch member 214 to the front end face of the latch holding portion 205 when the plunger 204 is retracted is formed in the guide groove 205a. Further, a spring holding portion 206 is fixedly provided on the rear end side of the injector body 202 inside the housing 203.

The latch holding portion 205 of the plunger 204
A compression spring 207 is interposed between the spring holding section 206 and the spring holding section 206. The compression spring 207 urges the plunger 204 forward (to the left in FIG. 19). Thereby, as described later, the compression spring 207 presses the plunger 204 forward, and the gasket 226 described later.
Can be moved to eject a chemical solution.

The plunger 204 is provided with a lever 208 for operation by an operator such as a patient. The plunger 204 is provided with a flange 209 and the housing 2 of the injector body 202.
A stopper 210 with which the flange 209 abuts is provided in the inside 03.

As shown in FIG. 20, the plunger 204
A recess 211 for accommodating a tube 225 to be described later is formed at the tip of the. Thereby, following the movement of the plunger 204, the tube 225 is
11 can be freely deformed.

A start button 212 for starting the movement of the plunger 204 is provided on the side wall of the housing 203.
Is provided. A start button 212 is connected to one end of the arm 213, and a latch member 214 is engaged with the other end of the arm 213 so that the latch member 214 can be separated from the side wall. The arm 213 is fixed to a pin 216 rotatably supported by the housing 203. A leaf spring 21 is provided between the side wall of the housing 203 and the arm 213.
5, whereby the other end of the arm 213 and the latch member 214 are connected to the pin 216 of the arm 213.
Is urged in a direction away from the side wall of the housing 203 around the center.

Therefore, the operator such as a patient
8, the latch member 214 is guided by the guide groove 205a to move the plunger 204 rearward against the urging force of the compression spring 207. Engage to hold plunger 204 in the standby position.

On the other hand, when the operator presses the start button 212, the latch member 214 approaches the side wall of the housing 203 via the arm 213 against the urging force of the leaf spring 215, and the latch member 214 and the plunger 204 The engagement of the latch holding portion 205 with the front end surface is released. Thus, the plunger 204 is pressed forward by the urging force of the compression spring 207, and moves a gasket 226 described later to inject the chemical.

A chemical solution container 217 for injecting a chemical solution is disposed in front of the plunger 204.

At the tip of the chemical solution container 217, the microneedle 101
Is provided. As shown in FIG. 8, the microneedle 101 has a needle part 110 punctured into the skin and a base part 120 supporting the needle part 110. And the needle part 11
0, as shown in FIG.
1 has a length located in the living epidermal cell layer 132 or near the boundary surface 141 between the epidermal cell layer 132 and the dermis layer 133. The configuration of the microneedle 101 is the same as that of the first embodiment, and a detailed description thereof will be omitted.

The cylindrical main body of the chemical solution container 217 is formed of a material that can withstand a predetermined high injection pressure of the chemical solution, and the material used is, for example, glass, plastic, metal, or two or more kinds. Desirably, it is selected from among composite materials composed of materials. However, even a material having low pressure resistance can be used by coating the periphery of the container with a reinforcing material such as metal. In addition,
It is preferable to form all or a part of the chemical solution container 217 from a transparent material because the chemical solution contained in the inside can be visually checked.

The housing 203 has a mounting portion 219 for mounting the chemical solution container 217. As shown in FIG. 21, the mounting portion 219 has an arc-shaped holding portion 220 for holding the chemical solution container 217, and a guide groove 221 formed between the two plate members. Also,
A projection 218 is formed on a side surface of the chemical solution container 217. As a result, the chemical solution container 217 is
And rotated 90 degrees, the protrusion 218 is locked in the guide groove 221, and the movement in the front-rear direction (the left-right direction in FIG. 19) is restricted.

The mounting part 22 formed on the housing 203
2, a drug solution reservoir 223 filled with a drug solution in advance is detachably mounted. The chemical solution reservoir 223 is provided with a plunger 224 for sucking and discharging the chemical solution, and also stores the chemical solution in the chemical solution container 217.
The tube 225 for leading to is connected. Also,
A scale for measuring the volume of the drug solution is formed outside the drug solution reservoir 223. However, this scale is
It may be formed outside the chemical solution container 217, or may be formed on both the chemical solution container 217 and the chemical solution reservoir 223. The chemical solution container 217 is preferably detachable from the injector main body 202 from the viewpoint of operability, but may not be detachable from the injector main body 202, and is previously integrated with or fixed to the injector main body 202. You may.

As the chemical solution reservoir 223, specifically, a prefilled type filled cartridge (chemical solution reservoir) or a chemical solution reservoir filled by sucking from a chemical solution vial is used.

As the shape of the chemical solution reservoir 223, a general syringe shape can be used, but any other shape having an injector shape can be used. As the material of the chemical solution reservoir 223, plastic, glass, or the like is used, and as the plastic, polypropylene, polyethylene, or the like is used. The drug solution filled in the drug solution reservoir 223 is a solution, gel or suspension containing a drug. The drug that can be used is not substantially limited as long as it is not a drug that is not suitable for transdermal administration. As main drugs, for example, the same drugs as those described in the first embodiment can be exemplified.

The tube 225 of the chemical solution reservoir 223 is
It is connected to an axial through hole 226 a formed in a gasket 226 that is reciprocally inserted into the chemical solution container 217. This facilitates the filling of the drug solution into the drug solution container 217.

The gasket 226 has a through hole 226a.
When the chemical liquid flows into the chemical liquid container 217 from the chemical liquid reservoir 223 via the tube 225 to allow the chemical liquid to flow, the gasket 226 is pressed to eject the chemical liquid from the chemical liquid container 217. Is formed with a check valve 227 which is closed to prevent backflow of the chemical from the chemical container 217 to the chemical reservoir 223.

Here, the check valve 227 is connected to the gasket 22.
6 are provided at the tips of the through holes 226a. As a result, at the time of injection, the chemical liquid flows through the through hole 226a of the gasket 226.
And the tube 225 is completely prevented from entering, so that an accurate injection amount of the chemical solution can be secured.

The gasket 226 and the check valve 227 are
It is formed by integral molding from butyl rubber, silicon rubber, or the like. As a result, the check valve can be configured very simply, downsized, the number of parts can be reduced, and the manufacturing cost can be reduced. Also,
As shown in FIGS. 22A and 22B, the check valve 227 has a conical shape when closed (FIG. 22A), and when opened, this conical shape opens (FIG. 22B). ). However, the shape of the check valve 227 is not limited to this, and for example, as shown in FIGS. 22C and 22D, a thin plate-shaped valve body may be formed. Furthermore, the check valve 227 does not necessarily need to be provided at the tip of the gasket 226, and may be located at another location.

As shown in FIG. 19, a cap 228 is attached to the tip of the chemical solution container 217. At the center of the cap 228, a seal member 228b made of rubber or the like is provided. A ring-shaped projection 228a is provided near the opening end of the cap 228.
Are formed. When the cap 228 is attached, the projection 2
28a is a ring-shaped projection 2 formed on the chemical solution container 217.
The cap 228 is locked to the chemical solution container 217 by going over the 17a.

The cap 228 is connected to the chemical reservoir 22.
3 is attached when the chemical liquid container 217 is filled with the chemical liquid. When the cap 228 is mounted, the check valve 22
7 is opened to allow the chemical solution to flow into the chemical solution container 217 and the cap 228 is attached to the microneedle 101 of the chemical solution container 217.
Of the seal member 228b is tightly adhered to ensure liquid tightness. Therefore, when the chemical is discharged from the chemical reservoir 223 by the plunger 224 and flows into the chemical container 217 via the tube 225 and the check valve 227,
The gasket 226 is automatically retracted in the chemical solution container 217, and the chemical solution is filled in the chemical solution container 217. That is, there is no need to pull the gasket 226 backward by the plunger 204. Moreover, this cap 228
By attaching to the injector body 202, infection from the air can be prevented.

Next, the operation of the liquid injector according to this embodiment will be described.

FIG. 23 is a cross-sectional view of the liquid injector according to the present embodiment, showing a state in which a liquid reservoir or the like is mounted. FIG. 24 is a cross-sectional view of the liquid injector according to the present embodiment. FIG. 25 is a diagram showing a state in which the plunger is set at the standby position, FIG. 25 is a cross-sectional view of the drug solution injection device according to the present embodiment, and a diagram showing a state in which the drug solution container is filled with the drug solution. It is sectional drawing of the chemical | medical solution injection apparatus which concerns on this embodiment, Comprising: It is a figure which shows the state which injected the chemical | medical solution.

First, as shown in FIG. 23, for example, the cover 203b is opened, the tube 225 is connected to the prefilled type filled chemical solution reservoir 223, and the chemical solution reservoir 223 is set in the mounting portion 222. Then, the plunger 204 is inserted into the chemical solution container 217 while the tube 225 connected to the back side of the gasket 226 accommodated in the chemical solution container 217 is positioned in the recess 211 of the plunger 204. And the drug solution container 217
On the mounting part 219. In this state, the chemical solution container 2
17 is rotated 90 degrees, and the projection 218 of the chemical solution container 217 is locked in the guide groove 221 of the mounting portion 219.

Next, as shown in FIG. 24, the operator such as a patient operates the lever 208 to move the plunger 204 backward against the urging force of the compression spring 207. As a result, the latch member 214 engages with the front end surface of the latch holding portion 205 of the plunger 204, and the plunger 2
04 is held at the standby position.

Next, as shown in FIG.
7 is fitted with a cap 228 at the tip thereof. Then, by moving the plunger 224, the liquid medicine is discharged from the liquid medicine reservoir 223 and filled in the liquid medicine container 217.

At this time, the check valve 227 at the tip of the gasket 226 is opened to allow the chemical solution to flow into the chemical solution container 217, and the seal member 228a of the cap 228 is brought into close contact with the microneedle 101 of the chemical solution container 217. Liquid tightness is ensured. Therefore, when the plunger 224 is moved to discharge the chemical solution from the chemical solution reservoir 223 and flow into the chemical solution container 217 via the tube 225 and the check valve 227, the gasket 226 is moved inside the chemical solution container 217. The medicine is automatically retracted, and the medicine is filled in the medicine container 217. When filling the chemical solution into the chemical solution container 217, the ejection port of the microneedle 101 may be closed by another member instead of the cap 228.

After the drug solution is filled in the drug solution container 217,
With the cover 203b closed and the cap 228 removed,
The tip of the drug solution container 217 is pressed against the skin surface at the drug solution injection site, and the start button 212 is pressed. Thereby, as shown in FIG. 26, the latch member 214 and the plunger 2
The engagement of the latch 04 with the front end surface of the latch holding portion 205 is released, and the plunger 204 is pressed forward by the urging force of the compression spring 207. As a result, the gasket 226 is moved forward, and the chemical is injected.

At the time of this injection, the check valve 227 at the tip of the gasket 226 is closed to prevent the backflow of the chemical from the chemical container 217 to the chemical reservoir 223. Note that when actually injecting a drug solution into a patient, the drug solution is repeatedly filled and injected into the injection container 17 several times to evacuate all the air in the drug solution container and then pressed against the skin to inject the drug solution. Is preferred. In addition, the air in the chemical solution container is removed by the chemical solution container 217.
After filling the liquid medicine into the liquid medicine, the cap 228 is once removed, and the liquid medicine in the liquid medicine reservoir 223 can be discharged from the microneedle 101.

As described above, also in the present embodiment, by pressing the tip of the drug solution container 217 against the skin surface, the tip of the needle portion 110 of the microneedle 101 can be inserted into the living epidermal cell layer 132 through the stratum corneum 131 or It can be located near the boundary surface 141 between the epidermal cell layer 132 and the dermis layer 133 (immediately below the epidermis), and in this state, it is possible to inject the drug solution, and the same effects as in the first embodiment are obtained. be able to.

In this embodiment, the chemical solution reservoir 22
Third, since a prefilled-type filled cartridge (medicine reservoir) can be used, a complicated filling operation in which the patient himself sucks the medicinal solution from the medicinal vial and fills the medicinal container each time is required as in the related art. With very simple operation, for example, an insulin injection can be made, and the device is extremely portable.

The embodiments described above are not described to limit the present invention, and various modifications can be made by those skilled in the art within the technical concept of the present invention.

For example, the drive source for generating the pressure for pressing the plunger for ejecting the chemical is not particularly limited as long as it can generate a predetermined strong pressure instantaneously. The driving source is preferably a high-pressure gas, elastic rubber, a solenoid valve, or the like, in addition to the above-described tension spring and compression spring.
When a high-pressure gas is used, it is necessary to have a gas reservoir and a gas filling mechanism, or a mechanism for mounting a cartridge filled with gas in advance, and a mechanism for releasing the gas and generating pressure. The type of gas is not particularly limited as long as it does not adversely affect the human body or the environment, such as nitrogen, carbon dioxide, and helium.

In the above embodiment, the drug solution container and the drug solution reservoir are detachable from the housing, but they may be formed or fixed integrally with the housing. Further, any of a configuration in which the chemical is filled in the chemical container or the chemical reservoir in advance and a configuration in which the chemical is appropriately filled by the user may be adopted.

[0107]

As described above, according to the present invention,
Place the tip of the microneedle in the epidermis cell layer that survived the stratum corneum,
Or, in a state where it is located near the boundary between the epidermal cell layer and the dermis layer, by a driving source that generates pressure, a medicinal solution is ejected and injected from the skin via the microneedle, so that the stratum corneum and There are no free nerve endings related to pain in the living epidermal cell layer, and almost no pain is felt even when the needle portion of the microneedle is punctured into the skin.

Further, it is not necessary to generate a high pressure such that the injected chemical solution penetrates the solid stratum corneum and the living epidermal cell layer in which the cells are dense, and the chemical solution is injected at a relatively low pressure. It is possible to do. In addition, since the injection method is used, the injection time per injection of the chemical solution can be extremely short.

Since the injection pressure of the drug solution can be reduced, the stimulation of the nerve network related to pain existing in the dermis layer is weakened correspondingly, and the pain is reduced. In addition, the durability of the components that require pressure resistance and impact resistance is relatively improved due to a decrease in the injection pressure of the chemical solution. Alternatively, the improvement in durability can contribute to weight reduction and downsizing of the constituent members.

Further, since the chemical can be injected and injected at a lower pressure, the diameter of the flow path for flowing the chemical can be reduced if the driving sources for generating the pressure are the same. Therefore, since the drug solution is injected with a smaller channel diameter, the contact area of the drug solution with the nerve network related to pain can be reduced, and the stimulation to the nerve network is reduced, and the occurrence of pain is further suppressed. .

[Brief description of the drawings]

FIGS. 1A and 1B are views showing a liquid injector according to a first embodiment of the present invention, wherein FIG. 1A is a plan view and FIG. 1B is a side view.

FIG. 2 is a horizontal sectional view of an injector body.

3A and 3B are views showing a spring fixing portion, wherein FIG. 3A is a plan view, FIG. 3B is a side view, and FIG. 3C is a left side view.

FIG. 4 is a sectional view taken along a line indicated by IV in FIG. 2;

FIG. 5 is a view as seen from the axial direction of the retainer.

FIG. 6 is a side view of the cartridge unit.

FIG. 7 is a sectional view of a cartridge unit.

FIGS. 8A and 8B are enlarged views showing a microneedle, wherein FIG. 8A is a view seen from the front and FIG. 8B is a side view.

FIG. 9 is a cross-sectional view showing a state where the needle portion of the microneedle is punctured into the skin.

FIG. 10 is an enlarged view showing a modification of the microneedle,
(A) is the figure seen from the front, (B) is the side view.

FIG. 11 is a horizontal sectional view of the injector body showing a state in which the plunger is moved backward by a predetermined distance and held while resisting the tension of a tension spring.

12 is a horizontal cross-sectional view of the liquid injector in a state where the cartridge is screwed into the injector main body in the state of FIG. 11;

FIG. 13 is a cross-sectional view showing an adapter and a vial filled with a chemical solution.

FIG. 14 is a cross-sectional view showing a state in which a drug solution is filled into a drug solution container via an adapter.

FIG. 15 is a horizontal sectional view showing a state before the liquid medicine administration of the liquid medicine injection device.

FIG. 16 is a horizontal cross-sectional view showing a state of the liquid injector after the liquid is administered.

FIG. 17 is a diagram showing the relationship between the deflection of a tension spring and the ejection force of a chemical solution.

FIG. 18A is a perspective view of an injector main body of an injection-type drug solution injector according to a second embodiment of the present invention, and FIG.
FIG. 3 is a plan view of the injector body shown in FIG.

FIG. 19 is a cross-sectional view of an injection-type liquid injector according to the present embodiment.

FIG. 20 is a perspective view of the vicinity of the tip of the plunger.

FIG. 21 is a perspective view showing a state when a chemical solution container is mounted.

FIGS. 22A to 22D are cross-sectional views of a gasket and a check valve.

FIG. 23 is a cross-sectional view of the drug solution injection device according to the present embodiment, showing a state in which a drug solution reservoir and the like are attached.

FIG. 24 is a cross-sectional view of the drug solution injection device according to the present embodiment, showing a state in which the plunger is set at a standby position.

FIG. 25 is a cross-sectional view of the liquid medicine injection device according to the present embodiment, showing a state in which the liquid medicine container is filled with the liquid medicine.

FIG. 26 is a cross-sectional view of the liquid medicine injection device according to the present embodiment, showing a state in which injection of the liquid medicine has been completed.

[Explanation of symbols]

 1,201: Chemical liquid injection device, 3,203: Housing, 6: Tension spring (drive source), 71, 217: Chemical liquid container, 8: Chemical liquid. 101: micro needle, 110, 110a: needle part, 111, 111a: flow path, 120, 120a: base part, 121, 121a: through hole, 207: compression spring (drive source), 223: chemical solution reservoir.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Takeo Ishii 1500 Inoguchi, Nakai-machi, Ashigara-gun, Kanagawa Prefecture Terumo Corporation F-term (reference) 4C066 AA07 AA09 BB01 CC01 CC05 DD03 DD04 EE14 FF03 FF05 HH12 KK01 KK02

Claims (14)

[Claims] 1. A drug solution injection device for injecting a drug solution from the skin, wherein a tip of a microneedle provided at an end portion of the device is inserted into a living epidermal cell layer beyond the stratum corneum, or between an epidermal cell layer and a dermal layer. A chemical liquid injection device characterized by injecting a chemical liquid by a driving source for generating pressure and injecting the liquid from the skin through the microneedles in a state where the liquid crystal liquid is positioned near the boundary surface between the liquid and the liquid. 2. A drug solution injection device for injecting a drug solution from the skin, comprising: a housing forming an outer frame of the drug solution injection device; a drug solution container accommodating the drug solution therein; and a tip that penetrates the stratum corneum when used. A microneedle having a length located in the epidermis cell layer or near the boundary between the epidermis cell layer and the dermis layer; and a drive source for generating pressure for injecting a drug solution in the drug solution container, The liquid medicine injecting device, wherein the liquid medicine in the liquid medicine container is injected from the skin via the microneedle. 3. The chemical injection according to claim 1, wherein the injection time of the chemical is one second or less, and the injection amount of the chemical is 0.01 to 2 ml per one time. apparatus. 4. The drug solution injector according to claim 1, wherein the microneedle has a needle portion whose length to be punctured into the skin is 0.02 to 1.0 mm. . 5. The microneedle, wherein the microneedle is punctured into the skin, and has a hollow needle part in which a flow path for flowing a drug solution is formed.
3. The liquid injector according to claim 1, further comprising a through-hole communicating with the flow path, and a base that supports the needle. 4. 6. The liquid injector according to claim 5, wherein the flow path of the needle portion is formed so that a cross-sectional area decreases as approaching a tip. 7. The microneedle has a solid needle portion pierced into the skin, a base portion provided with a through hole and supporting the needle portion, and a part of an outer surface of the needle portion. By notching and communicating with the through hole of the base portion, or by providing the through hole of the base portion near the base of the needle portion,
3. The chemical liquid injector according to claim 1, wherein a flow path for flowing the chemical liquid is formed. 8. The liquid injector according to claim 5, wherein the through hole of the base portion is formed such that a cross-sectional area decreases as approaching a tip. 9. The microneedle according to claim 1, wherein the microneedle has an ejection port for ejecting a chemical solution, and the diameter of the ejection port is 0.01 to 0.5 mm. Chemical injection device. 10. The liquid injector according to claim 1, wherein the microneedle has a plurality of needles pierced into the skin. 11. The microneedle is formed of a material selected from metals, ceramics, plastics, and composite materials composed of two or more materials so as to withstand the injection pressure of a chemical solution. 3. The liquid injector according to claim 1, wherein 12. The liquid injector according to claim 1, wherein the driving source is selected from a group consisting of a spring, gas, rubber, and a solenoid valve. 13. The pressure for injecting a chemical solution is 1
3. The liquid injector according to claim 1, wherein the pressure is 1.8 MPa or less. 14. The liquid injector according to claim 2, wherein the microneedle is detachably provided to the liquid container.