JPWO1998010815A1 - Sliding valve for syringe, syringe, and kit preparation - Google Patents

Abstract

(57) [Abstract] By using a sliding valve for a syringe made from rubber to which a lubricating component is chemically bonded, a sliding valve for a syringe with good operability can be obtained without using a silicone coating treatment.

Description

[Detailed Description of the Invention] Sliding Valve for Syringe, Syringe, and Kit Preparation [Technical Field] The present invention relates to a sliding valve for use in syringes such as disposable syringes.

[Background Art] Injectable drugs administered by injection have long been supplied in ampoules or vials. However, there are concerns about the risk of glass powder being released when the ampule is opened, and the risk of various disorders occurring when the drug comes into contact with air. Recently, however, drugs have increasingly been supplied in kit form, in which the drug is pre-filled in a disposable syringe.

Disposable syringes are widely used today because they are literally disposable, convenient, and pose no risk of infection, such as serum hepatitis. They consist of a resin or glass barrel and a plunger with a sliding valve made of rubber or a plastic with rubber-like properties (hereinafter referred to as "rubber").

Two types of syringe barrels have been used: glass and polypropylene. Glass syringes have been considered particularly suitable for kit formulations due to their excellent chemical resistance and gas barrier properties, but they are expensive and have problems with disposal after use. On the other hand, polypropylene syringes have inferior chemical resistance and gas barrier properties, but they are inexpensive and can be disposed of by incineration after use.

Both syringes had silicone coatings on the inside of the syringe body and the sliding valve to improve the sliding properties of the sliding valve.

For safe and effective injections, the injection must be introduced into the body slowly, which requires smooth movement of the sliding valve. Furthermore, in the case of kit formulations in which the drug solution is contained within a cylinder and a sliding valve is provided in addition to the plunger as a front stop, there are two sliding valves inside the cylinder, which significantly reduces ease of handling due to poor sliding properties. Silicone coating, which improves this, plays an extremely important role.

However, recently, the safety of silicone coating has come into question. For this reason, amorphous polyolefin (a copolymer of cyclic olefin and α-olefin) cylinders have been proposed as a solution to the drawbacks of glass and polypropylene cylinders while eliminating the need for silicone coating. Unlike glass syringes, amorphous polyolefin cylinders can be manufactured with a smooth, mirror-like finish on the inner surface, providing excellent sliding properties without the need for silicone coating.

However, actual testing revealed that while a certain degree of lubricity could be achieved without silicone coating, it was not sufficient to achieve the lubricity required for a syringe, and so silicone coating is still used today.

As an alternative to silicone coating, fluororesin layers have been applied to the interior of the cylinder or the surface of the sliding valve. However, these methods are prone to adhesion at the contact points between the sliding valve and the interior of the cylinder, which is particularly problematic in cases where the sliding valve is retained for long periods of time outside the tip of the cylinder interior and must be injected into the patient from that position, such as in kit formulations. Furthermore, microscopic cracks can develop at the adhesion points between the interior of the cylinder and the sliding valve, raising questions about the gas barrier properties and, ultimately, the stability and safety of the drug.

Although methods for forming a surface coating on the rubber sliding valve have been proposed, preventing peeling is difficult and unreliable. On the other hand, sliding valves incorporating fine powder of sliding material such as Teflon have also been proposed, but there are similar concerns about the powder falling off.

As such, there has been a demand for a safe sliding valve that provides good lubrication, allows the syringe to fully utilize its increasingly sophisticated and complex functions, and is free from the risk of foreign matter peeling or detaching.

An object of the present invention is to provide a syringe that solves the above-mentioned problems of the prior art and has a sliding valve that is free from the risk of peeling or detachment and has good lubricity.

[Disclosure of the Invention] The sliding valve for a syringe of the present invention is made of rubber to which a lubricating component is chemically bonded.

In this invention, "rubber" refers to rubber or plastics with rubber properties. Examples include nitrile rubber, hydrogenated nitrile rubber, ethylene-propylene-diene rubber, and ethylene-propylene rubber. Furthermore, the material must be suitable for medical use, being free from or capable of eluting organic or inorganic substances, such as plasticizers, or harmful metals, which may adversely affect living organisms. Furthermore, the material must be resistant to at least the intended drug.

In the present invention, the lubricating component is preferably a synthetic oil-based lubricant. Examples of such lubricants include hydrocarbon-based, polyglycol-based, and fluorine-based lubricants. These lubricating components are derivatized and chemically bonded to the rubber. The amount of chemically bonded lubricating component has a significant effect on lubrication, so it must be determined after careful consideration.

Chemical bonding may be achieved by a conventional method such as a conventional amide bond or ester bond, but a method may also be employed in which a group reactive with a rubber crosslinking agent is previously introduced into the lubricating component and then the crosslinking is carried out simultaneously with the crosslinking of the rubber.

Furthermore, in the case of less reactive lubricants such as fluororesins (such as polytetrafluoroethylene and copolymers of tetrafluoroethylene with other comonomers), electrophilic reagents (such as hindered phenols or Grignard reagents) can be added to these lubricants during rubber molding, allowing for chemical bonding during the granule reaction.

The lubricant preferably has a diameter of 10 μm or more and 50 μm or less. The amount added is preferably 5 to 60 parts by weight, and more preferably 10 to 50 parts by weight, per 100 parts by weight of the rubber component.

The use of fluororesin as a lubricant will be described in detail below. Specifically, when fluororesin is used as a lubricant, the sliding valve moves very smoothly and starts moving smoothly, which not only facilitates injection into a specific location, such as intravenous injection, but also makes it extremely easy to inject a specific amount, for example, in kit preparations where the injection volume is tailored to the patient rather than injecting the front portion of the injection liquid in the cylinder.

Furthermore, it can easily administer highly viscous, high-molecular-weight sodium hyaluronate into the knee joint cavity, which was difficult to do with conventional syringes.

In the above, the electrophilic reagent must be compatible with the rubber component and not impair the rubber properties of the matrix. Examples of such reagents include hindered phenols such as pentaerythrityl tetrakis[3-(3,5-t-butyl-4-hydroxyphenyl)propionate], 2,2-thiodiethylenebis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], 2,2-thiobis(4-methyl-6-t-butylphenol), N,N'-bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionyl]hydrazine, and Grignard reagents containing chlorine or iodine, such as isopropylmagnesium chloride and isooctylmagnesium iodide.

These electrophilic reagents are generally compounded in an amount of 0.1 to 10 parts by weight, and more preferably 0.2 to 5 parts by weight, per 100 parts by weight of the rubber component.

These lubricants and electrophilic reagents are blended with rubber raw materials (green resin and vulcanizing agent) and then vulcanized in a mold at a temperature of approximately 150°C or higher to obtain a sliding valve for syringes with chemically bonded lubricating components. In addition to the above, various modifiers can be added as needed, but of course, they must be safe for use as raw materials for sliding valves for syringes.

In the sliding valve for syringes of the present invention, the lubricating component is integrated with the rubber by chemical bonding, so there is absolutely no risk of the lubricating component being mixed into the medicine due to elution or peeling.

Furthermore, since the rubber itself has lubricity, silicone coating or lubricating film is not required, making it safer.

The cylinder portion, which is combined with the sliding valve to form the syringe, can be made of commonly used materials, such as glass, polyolefin polymers such as polypropylene and amorphous polyolefin, etc. In particular, materials containing cyclic olefin copolymers as units are desirable because they meet the various performance requirements for syringes, including safety, heat and cold resistance, transparency, high precision, gas barrier properties, and chemical resistance, and can be easily incinerated after use.

BEST MODE FOR CARRYING OUT THE INVENTION Examples (Examples 1-3 and Comparative Examples 1-4 Using a Conventional Syringe) First, the operability of the sliding valve for a syringe of the present invention was evaluated using a conventional syringe. Here, a rubber sliding valve to which a lubricating component according to the present invention was chemically bonded was fabricated as follows.

Specifically, nitrile rubber (NBR, before vulcanization), stearic acid, zinc oxide, sulfur (colloidal sulfur), HAF carbon, di-2-ethylhexyl phthalate (DOP), N,N'-bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionyl]hydrazine, vulcanization accelerators N-cyclohexyl-2-benzothiazolylsulfenamide (CZ; Kawaguchi Chemical Industry Co., Ltd.), dibenzothiazyl disulfide (DM; Kawaguchi Chemical Industry Co., Ltd.), and tetramethylthiuram disulfide (TT; Kawaguchi Chemical Industry Co., Ltd.), and polytetrafluoroethylene powder (PTFE powder, particle size 20 μm to 30 μm) were mixed in the weight ratio shown in Composition 1 in Table 1. The unvulcanized rubber composition was heated to 180°C in a mold and molded into a sliding valve (Example 1).

In addition, compositions shown in Compositions 2 to 5 in Table 1 were prepared and similarly vulcanized to prepare sliding valves (Examples 2 and 3, and Comparative Examples 1 and 2, respectively).

These were evaluated as syringe sliding valves along with the sliding valve of Example 1, a conventional silicone-coated butyl rubber sliding valve (obtained from Maeda Sangyo; hereafter referred to as the "silicone-coated butyl rubber sliding valve"; Comparative Example 3), and an uncoated sliding valve (obtained from Maeda Sangyo; hereafter referred to as the "uncoated butyl rubber sliding valve"; Comparative Example 4).

The test involved a monitor test using 10 physicians as monitors, using 5 ml amorphous polyolefin cylinders (obtained from Maeda Sangyo Co., Ltd.) Note that a silicone-coated cylinder was used only in the test using a silicone-coated butyl rubber sliding valve, and a non-silicone-coated cylinder was used in the other cases.

Tests were conducted simulating intravenous injection using saline as the injection fluid. The feel of the plunger when first pressing it (initial sliding) and the ease of stopping the injection after 4 ml (ease of handling) were each rated on a 10-point scale, with 10 being the best and 1 being the worst. The results were averaged and rounded to the nearest whole number. The results are shown in Table 2. The details of the samples were not explained to each monitor, and the tests were conducted in random order.

From Table 2, it can be seen that the operability of the sliding valves of compositions 1 to 3, which are sliding valves to which the lubricating component according to the present invention is chemically bonded, is remarkably good.

The sliding valves of compositions 1 to 4 all contain polytetrafluoroethylene powder with particle diameters of 20 μm to 30 μm. If these particles were to detach and be introduced into the body, particularly into blood vessels, there is a risk of obstructing blood flow. Therefore, we investigated whether or not the particles would detach from the sliding valves.

Three of these sliding valves were placed in a test tube, and 10 ml of saline solution, previously filtered through a 0.45 μm pore size filter, was added. The tubes were then autoclaved at 121°C for 20 minutes. After cooling to room temperature, the sliding valves were removed, and the saline solution was further filtered through a 0.45 μm pore size filter. The filter surfaces were then examined using a scanning electron microscope. Only when the sliding valve of composition 4 was used were some particles (10-20 μm in diameter) observed. Fluorine was confirmed to be present in these particles using an electron probe X-ray microanalyzer. However, when the sliding valves of compositions 1-3 were used, no particles were observed on the filter. This confirmed that the sliding valves of compositions 1-3, which have the lubricating component chemically bonded to them according to the present invention, completely prevented the polytetrafluoroethylene powder from detaching.

Examples (Examples and Comparative Examples Using a Kit-Type Syringe) This section describes examples using a kit-type syringe.

Figures 1(a) to 1(d) show a kit-type syringe having a sliding syringe valve made of rubber to which a lubricating component according to the present invention is chemically bonded.

Figure 1(a) shows the state before use, (b) shows the state during injection, (c) shows the state after injection is completed, and (d) shows the cross-sectional shape of the cylinder (cross-sectional view taken along I-I in Figure 1(a)).

In the figure, reference numeral 21 denotes a cylinder made of amorphous polyolefin, having openings 44 and 45 at both ends, with the tip of the opening 44 side having a hook-shaped cross section forming a hook-shaped tip 22. Reference numeral 23 denotes the rear end of the cylinder, 24 denotes a bulge, and 25 denotes a sliding valve of the plunger. As shown in Figure 1(d), bulge 24 bulges out from a portion of the circumference of cylinder 21, forming a communication passage 24' therein.

A front stopper slide valve 26 is fitted near the center of the interior of the cylinder 21. The plunger slide valve 25 and front stopper slide valve 26 are made of rubber according to composition 1 of the present invention and have lips formed on their outer surfaces. The left end of the cylinder 21 in the drawing is sealed watertight by an end partition 27, thereby forming a chamber 28 between the plunger slide valve 25 and the front stopper slide valve 26 and a chamber 29 between the end partition 27 and the front stopper slide valve 26 within the cylinder. An injection connection needle 30 is fitted into the end partition 27, and a cap 31 is attached to the injection needle connection 30.

Next, the operation of this syringe will be explained. In Figure 1(a), the cylinder 21 is stored with the injection agent filled in the empty chamber 28 and the empty chamber 29 empty. To use the syringe, first remove the cap 31 and insert the injection needle 32 using the Luer lock method. Next, with the injection needle 32 facing upward, press the plunger as shown in Figure 1(b). This positions the front stopper sliding valve 26 in the communication passage 24' of the bulge 24, and the injection agent in the chamber 28 moves into the empty chamber 29. After all air has been expelled from the empty chamber 29, the injection needle 32 is injected into the patient. The injection agent passes through the injection needle 32 and reaches the patient's body.

Figure 1(c) shows the completed injection state. The plunger is pushed in, bringing the end partition 27, front stopper sliding valve 26, and plunger sliding valve 25 into tight contact with one another. At this point, the tip (needle side) of the plunger sliding valve 25 reaches passage 24', allowing all of the injection material in chamber 28 to be injected. The axial thicknesses of end partition 27, front stopper sliding valve 26, and plunger sliding valve 25, as well as the length and position of bulge 24, are determined so that passage 27b of end partition 27 is also located within passage 24'. Because two sliding valves are moved simultaneously during injection, syringes without lubricant require force, making delicate movements such as intravenous injection difficult. However, in the above-described embodiment (Example 1) of the present invention, a sliding valve with good lubrication is used, eliminating the need for a lubricant, allowing for an extremely smooth injection operation and allowing the injection solution to be introduced slowly into the body.

Using this kit-type syringe and seven types of sliding valves obtained in the same manner as in the evaluation of standard syringes, a monitoring test was conducted simulating the injection of sodium hyaluronate into the knee joint cavity using sodium hyaluronate with an average molecular weight of 900,000.

Assuming a kit formulation, a 5 ml amorphous polyolefin cylinder was prefilled with 2.5 ml of 1% sodium hyaluronate solution (a viscous liquid). Using the seven types of sliding valves described above, prototype kit syringes (see Figure 1) were fabricated using standard manufacturing methods and left in a room at room temperature for three months. These syringes were used to draw 1 ml of lidocaine hydrochloride from a vial into each syringe, and then the entire amount was administered. Note that silicone-coated cylinders were used only in tests using silicone-coated butyl rubber sliding valves; non-silicone-coated cylinders were used in all other cases.

The sliding properties of these valves were evaluated by 10 orthopedic surgeon monitors on a 10-point scale, with 10 being the best and 1 being the worst. The results were averaged and rounded to the nearest whole number. The results are shown in Table 3.

From Table 3, it can be seen that when the sliding valves according to the present invention, which are the sliding valves of compositions 1 to 3, are used and stored as a kit preparation, the operability is excellent.

In particular, the superior operability of the sliding valves made with compositions 1 to 3 compared with the sliding valve made with composition 4, which also contains PTFE powder, is a notable effect of the lubricating components of the sliding valves made with compositions 1 to 3 being fixed by chemical bonding.

[Example 4] Figure 2(a) shows Example 2, a kit-type syringe α that has a sliding valve according to the present invention and has undergone sealing and peeling treatment.

In the figure, the seal is designated by the reference numeral 1, and the plastic cap is designated by the reference numeral 2. The cap 2 is equipped with a twist plate 2a, which, as will be described later, facilitates the removal of the cap 2.

The tip of kit syringe α is a luer lock type, and luer lock portion 3 prevents the needle from accidentally detaching. Luer lock portion 3 has a groove 3a that fits over a protrusion 2b on cap 2. As mentioned above, cap 2 is made of resin and can be easily removed from luer lock portion 3 by twisting twist plate 2a with the fingers (see Figures 2(a) and 2(b)). Figure 3(a) shows the plunger rod 107 attached.

Seal 1 is formed by dipping. When kit-type syringe α is sterilized with superheated steam, it prevents steam from entering the interior of cap 2, the needle connection portion, and the interior of kit-type syringe α, and also prevents bacteria from entering these spaces after sterilization. Seal 1 can be made of a material such as a photocurable resin or a thermosetting resin. However, it must be a material that can withstand the sterilization conditions and allow for easy removal of cap 2. The thickness of seal 1 is selected appropriately, taking into account the sterilization conditions and ease of cap 2 removal. Seal 1 can also be made of a shrinkable film that meets the above requirements. However, depending on the film's condition, it may not be possible to cut cleanly at the boundary between cap 2 and luer lock portion 3, which may interfere with the connection between the needle and syringe α. Therefore, appropriate measures are required.

In FIG. 2(a), a large-diameter expanded portion (bulge portion) 87 is integrally molded at the tip of a cylinder 86. A circular cross-sectional space 89 within the expanded portion 87 can accommodate sliding valves 90 and 91 within the cylinder 86, with an outer diameter gap 92 (FIGS. 4 and 9) remaining. Furthermore, a bottom wall 93 of the expanded portion 87 is provided with a plurality of support protrusions 94 for the sliding valve 90, allowing medicinal solutions 96 and 97 within the cylinder 86 to be introduced into an inner bore 98a of a syringe needle connection portion 98 (FIG. 4) connected to the expanded portion 87 through the outer diameter gap 92 and gaps 95 formed by the protrusions 94 (FIG. 9).

The cylinder 86 may be made of glass, but it is best to use a synthetic resin material such as amorphous polyolefin, which is highly moldable and can be formed into a mirror-like shape, as this provides good lubrication.

In this example, the outer peripheral wall of the expanded diameter portion 87 is integrally connected to the outer peripheral wall of the straight portion 88 via an annular step portion 99.

Two rubber sliding valves (front stopper 90 and middle stopper 91) are disposed within the straight section 88 of the cylinder 86, forming a serial dispensing kit-type syringe α. In FIG. 2(a), the front sliding valve 90 is located within the straight section 88 slightly rearward of the enlarged diameter portion 87, and the middle sliding valve 91 is located approximately in the center of the straight section 88. A first medicinal liquid 96 is filled between the front sliding valve 90 and the middle sliding valve 91, and a second medicinal liquid 97 is filled between the middle sliding valve 91 and the rear plunger (end stopper) 100. For example, by using a local anesthetic as the first medicinal liquid 96 and sodium hyaluronate, a treatment for knee osteoarthritis, as the second medicinal liquid 97, the patient's pain during administration of the treatment can be reduced.

As shown in Figures 5 to 7, each of the sliding valves 90, 91 is made of rubber (nitrile rubber) chemically bonded with the lubricating component according to the present invention, and is constructed of two types of rubber (main body 101 and support member 102) with different elasticity due to differences in the crosslinking state. When the sliding valve 90 enters the enlarged diameter portion 87 of the cylinder 86 from the straight portion 88, a portion 103 of one of the rubber members (support member) 102, which is flexible and easily expands and contracts, protrudes radially, supporting the sliding valve 90 without rattle within the enlarged diameter portion 87 of the cylinder 86 and maintaining a uniform outer diameter clearance 92.

In Fig. 5, one rubber member (support member) 102 is assembled into the straight portion 88 of the cylinder 86 with a higher compression ratio, and when the sliding valve 90 is in a nearly released state as shown in Fig. 6, one rubber member (support member) 102 expands more than the other rubber member (main body) 101. Since the front sliding valve 90 and the intermediate tank sliding valve 91 are identically constructed, the cross-sectional shape and operation of the intermediate sliding valve 91 are also the same as those shown in Figs. 5 and 6.

Of the above-mentioned sliding valves, the main body 101 was obtained in the same manner as the sliding valve of Example 1.

The main body 101 is formed in a generally short cylindrical shape, and the support member 102 is composed of a generally cylindrical central portion 104 located in the center of the main body 101 and a plurality of generally fin-shaped expansion portions (protrusions) 103 extending radially from the central portion 104 into the main body 101.

As shown in Figure 6, the tip (support protrusion) 103a of the expansion/contraction portion 103 protrudes outward from the outer peripheral surface 101a of the main body 101 in a free state and contacts the inner surface 87a of the cylinder expansion portion 87. The support protrusion 103a has a semicircular cross section and contacts the inner surface of the cylinder 86 with low sliding resistance.

As shown in Figure 7, the telescopic portion 103 of the support member 102 is located in the axial center of the main body 101. The axial length of the telescopic portion 103 is set longer than the thickness of the telescopic portion 103, forming a generally rectangular plate. Both axial ends of the main body 101 have annular lip portions 105 that slide against the inner surface of the cylinder straight portion 88, and annular grooves 106 (Figure 4) between the lip portions. The center portion 104 (Figure 2) of the support member 101 extends axially in a boss-like shape, exposing a central tip surface 104a at one end of the main body 101. As shown in Figure 7, the central portion of the main body 101 is formed with a diameter slightly smaller than the outer diameter of the annular lip portions 105 at both ends.

The main body 101 is made of a hard material that is less likely to deform and stretch, while the supporting member 102 is made of a soft material that is more likely to deform and stretch, with elasticity equal to or greater than that of the main body 101 (the property of an object that, when subjected to an external force, undergoes a change in shape or volume within a certain limit, returns to its original state when the force is removed).

That is, the support member 102 is made of a material with a lower elastic modulus (higher compressibility) than the main body 101. The main body 101 and the support member 102 are integrally and closely attached to each other.

The support member 102 can also be made of a more compressible material, such as a porous material with independent pores. It is also possible to use the same material with different compressibility (elastic modulus).

The slide valves 90, 91 are formed by first molding the body 101, for example by insert molding, which is well known in the art of injection molding, and then inserting the body 101 into a separate mold into which the support member 102 is injection molded.

Upon completion of molding, the main body 101 and the support member 102 are in close contact at their interface. However, as shown in Figure 5, when the telescopic portion 103 of the support member 102 is compressed against the inner wall surface of the cylinder straight portion 88, a portion of the telescopic portion 103 moves along the side wall 101b on the main body 101 side and retracts radially inward. The outer peripheral surface of the main body 101 (annular lip portion 105) then tightly contacts the inner surface 88a of the cylinder straight portion 88, sealing in the chemical solution 95 as shown in Figure 2. The forward sliding valve 90 isolates the chemical solution 96 from the space 89 within the expanded diameter portion 87, preventing the intrusion of bacteria and other contaminants into the chemical solution 96.

A plunger is attached to this kit-type syringe α as shown in FIG. 3. When the plunger is pressed, the sliding valve 90 enters the cylinder enlarged diameter portion 87 as shown in FIG. 6. Due to its high elasticity, the telescopic portion 103 protrudes radially outward beyond the main body 101, stably supporting the sliding valve 90 against the enlarged diameter portion 87. The main body 101 also expands outward due to its elasticity. However, the inner diameter of the enlarged diameter portion 87 is set larger than the external diameter of the sliding valve main body 101 in its free state. Therefore, a gap 92 for discharging the drug solution is formed between the adjacent telescopic portions 103, 103 and the cylinder enlarged diameter portion 87 and the sliding valve main body 101.

A gap 92 of approximately 0.1 to 0.5 mm is sufficient, and the tips (supporting portions) 103a of the radially extending expansion/contraction portions 103 maintain this gap 92 constant along the circumference, thereby maintaining a constant flow rate and velocity of the medicinal solution 96 and stabilizing the operating force of the plunger rod 107 (Figure 4). A minimum of three expansion/contraction portions 103 are sufficient; six, as in this example, ensures stable positioning of the sliding valve 90 within the enlarged diameter portion 87.

In FIG. 4, the first medicinal solution 96 passes through the gap 92 on the outer side of the forward sliding valve 90 and is discharged from the inner hole 98a of the needle connecting portion 98 into the injection needle 107'.

FIG. 8 is a cross-sectional view taken along line CC of FIG. 2, showing the support projection 94 formed integrally with the bottom wall 93 of the expanded diameter portion 87 of the cylinder.

The protrusions 94 abut against the front end of the forward sliding valve 90 to create a gap 95 for discharging the drug solution between the forward sliding valve 90 and the bottom wall 93 of the expanded diameter portion. They are formed approximately midway between the inner hole 98a of the needle connection portion 98 and the inner wall surface of the expanded diameter portion 87. In this example, four protrusions 94 are provided at equal intervals to stably support the forward sliding valve 90. The number of protrusions 94 should be at least one, and preferably three or more. The height of each protrusion 94 should be approximately 1 mm.

FIG. 9 shows the state in which the plunger rod 107 is further pushed from the state shown in FIG. 4, discharging the first medicinal liquid 96, causing the intermediate sliding valve 91 to enter the expansion portion 87, and discharging the second medicinal liquid 97 begins.

As described above, the intermediate sliding valve 91 has a support member 102 inside the main body 101, similar to the front sliding valve 90. The second chemical solution 97 passes through the gap 92 between the main body 101 and the enlarged diameter portion 87 of each of the intermediate sliding valve 91 and the front sliding valve 90, and is discharged via the gap 95 on the bottom wall 93 side of the enlarged diameter portion 87.

10 shows the state after the second chemical solution 97 has been dispensed. Two sliding valves 90 and 91 are housed in the expanded diameter cylinder 87, and the plunger 100 stops when it abuts against the intermediate sliding valve 91.

The above example illustrates the structure of a dispensing syringe using multiple sliding valves (made of rubber with a lubricating component chemically bonded thereto) 90, 91. However, syringes using sliding valves made of rubber with a lubricating component chemically bonded thereto according to the present invention are not limited to dispensing syringes; they can also be used in standard kit-type syringes that use a single sliding valve (front stopper 90) for single-component injection, or in kit-type syringes that are dissolved before use.

Although the above description has focused primarily on syringes having cylinders (syringe barrels) made of amorphous polyolefins, the sliding valve of the present invention can be suitably used with syringes generally having cylinders made of other materials, such as polyolefins such as polypropylene or glass, in addition to amorphous polyolefin cylinders.

[Advantages of the Invention] By using the sliding valve for syringes of the present invention, it is possible to achieve good sliding properties while eliminating the need for lubricants that may have adverse effects on living organisms, or sliding materials or surface coatings that may peel or fall off.

[Brief Description of the Drawings] Figure 1 shows a syringe with a sliding valve according to the present invention. (a) shows the syringe before use, (b) shows the syringe during injection, (c) shows the syringe after injection, and (d) shows the cross-sectional shape of the cylinder.

FIG. 2(a) shows a kit-type syringe α having a sliding valve according to the present invention and having undergone a seal and peel treatment, while FIG. 2(b) shows the state near the tip of the kit-type syringe α.

FIG. 3(a) is a diagram showing the state in which the cap of the kit-type syringe α has been removed.

On the other hand, (b) shows the state near the tip of FIG. 3(a).

Figure 4 shows the kit-type syringe α with a needle attached and the air removed from the cylinder.

FIG. 5 is a cross-sectional view showing the state when the sliding valve is in the straight portion.

FIG. 6 is a cross-sectional view showing the state when the sliding valve is in the enlarged diameter portion.

FIG. 7 is a perspective view showing the state when the sliding valve is in the enlarged diameter portion.

FIG. 8 shows a supporting protrusion provided on the bottom wall.

FIG. 9 is a diagram showing a state in which a part of the liquid medicine in the kit-type syringe α has been injected.

FIG. 10 shows the state when the injection operation is completed.

[Explanation of Symbols] 21 Cylinder 24 Bulging Portion 27 End Partition 25 Plunger Slide Valve 26 Front Stopper Slide Valve 27b Passage 28 Chamber 30 Needle Connection Portion 32 Needle α Kit-Type Syringe Having a Slide Valve of the Present Invention and Having been Sealed and Peel-Treated 1 Seal 2 Cap 2a Twist Plate 2b Convex Portion 3 Luer Lock Portion 3a Groove 86 Cylinder 87 Enlarged Diameter Portion 88 Straight Portion 90 Front Slide Valve 91 Middle Slide Valve 92 Gap 93 Bottom Wall 94 Support Protrusions 96, 97 Medicinal Solution 98 Needle Connection Portion 99 Step Portion 101 Slide Valve Body 101a Outer circumferential surface 102 Support member 103 Expandable portion 103a Support protrusion 104 Center portion 105 Annular lip portion 106 Annular groove 107 Plunger rod

───────────────────────────────────────────────────── Continued from the front page (81) Designated Countries EP(AT, BE, CH, DE, DK, ES, FI, FR, GB, GR, IE, IT, L U, MC, NL, PT, SE), OA (BF, BJ, CF , CG, CI, CM, GA, GN, ML, MR, NE, SN, TD, TG), AP (GH, KE, LS, MW, S D, SZ, UG, ZW), UA (AM, AZ, BY, KG , KZ, MD, RU, TJ, TM), AL, AM, AT , AU, AZ, BA, BB, BG, BR, BY, CA, CH,CN,CU,CZ , DE, DK, EE, ES, F I, GB, GE, GH, HU, IL, IS, JP, KE , KG, KR, KZ, LC, LK, LR, LS, LT, LU, LV, MD, MG, MK, MN, MW, MX, N O, NZ, PL, PT, RO, RU, SD, SE, SG , SI, SK, SL, TJ, TM, TR, TT, UA, UG, US, UZ, VN, YU, ZW (Note) This publication is based on the international publication by the International Bureau (WIPO). Please note that the effect of the international publication of the Japanese-language patent application (Japanese-language utility model registration application) related to this publication arises pursuant to Article 184-10, Paragraph 1 of the Patent Act (Article 48-13, Paragraph 2 of the Utility Model Act), and is unrelated to this publication.

Claims (12)

[Claims] 1. A sliding valve for a syringe, characterized in that the lubricating component is made of chemically bonded rubber. 2. The sliding valve for a syringe according to claim 1, wherein the lubricating component is polytetrafluoroethylene. 3. The sliding valve for a syringe according to claim 1 or 2, wherein the lubricating component is chemically bonded to the sliding valve by an electrophilic reagent. 4. The sliding valve for a syringe according to any one of claims 1 to 3, wherein the electrophilic reagent is one or more selected from the group consisting of hindered phenols and Grignard reagents. 5. The sliding valve for a syringe according to claim 1, characterized in that it is made of two or more members having different elastic moduli. 6. The sliding valve for a syringe according to claim 1, characterized in that it is made up of two or more members having different compression rates when housed in the cylinder portion. 7. A sliding valve for a syringe, comprising one or more members selected from the group consisting of hindered phenols and Grignard reagents, and a lubricating component. 8. A syringe having a sliding valve made of rubber to which a lubricating component is chemically bonded. 9. The syringe according to claim 8, wherein the cylinder portion is made of a material selected from amorphous polyolefin, glass, and polypropylene. 10. A kit formulation characterized by using a sliding valve made of rubber to which a lubricating component is chemically bonded. 11. The kit preparation according to claim 10, characterized in that it has a removable cap that covers the injection needle connection portion and a seal that isolates the interior from the outside air. 12. The kit preparation according to claim 11, further comprising a mechanism for facilitating removal of the cap.