JPH0155027B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a syringe filled with a medicinal solution in advance.

This type of syringe eliminates the need for transferring the drug solution from the conventional drug container to the syringe at the time of use, and there is a risk of contamination by bacteria or contamination with glass or rubber pieces. Not only is it superior in that it is not expensive, but when the drug solution is extremely expensive, the amount that remains on the drug solution container and the amount that is lost during transfer cannot be ignored. It is extremely effective to avoid. Various methods have been proposed for manufacturing this type of syringe by filling the syringe with a drug solution, which also has the effect of preventing misuse due to transfer of the drug solution. After fixing the needle and creating a negative pressure inside the syringe, the syringe needle attachment tube at the tip of the syringe is immersed in the drug solution, and the negative pressure inside the syringe is used to fill the drug solution. There is a way to insert a gasket inside. When using this method, it is possible to fill multiple syringes with drug solution at the same time, but since a vacuum atmosphere must be created before insertion, there are time constraints and special methods that can be used to maintain airtightness are required. If you have to work inside a container, the inner diameter of the syringe barrel varies, the insertion position of the plunger rod is inconsistent, and the uneven shape of the gasket surface is uneven, so it is difficult to accurately deliver the specified amount. It is difficult to fill the chemical liquid, and therefore a larger amount of the chemical liquid than the predetermined amount must be filled, and if the chemical liquid is expensive, there is an inconvenience that the product cost increases.

The present invention eliminates such conventional drawbacks and provides a method for manufacturing a syringe filled with a drug solution, which can reliably fill only a predetermined amount of an expensive drug solution.
In a method for manufacturing a syringe filled with a drug solution, in which a barrel for attaching a syringe needle at the tip of the syringe is closed and a drug solution is filled from the rear end of the syringe barrel, the opening at the rear end of the syringe barrel is closed with a stopper. The drug solution is injected into the syringe barrel from the rear end opening, and then the hollow tube is inserted from the rear end of the syringe barrel along its inner surface to a position slightly away from the drug solution surface to close the syringe barrel. The inside of the syringe and the outside of the syringe are fixed in communication, and then a plunger rod with a gasket at the tip is inserted through the rear opening of the syringe, and the gasket tip is advanced to the tip of the hollow tube to expel the air inside the syringe. After that, the hollow tube is removed.

A detailed explanation will be given below with reference to FIGS. 1 and 2 showing an example of the implementation of the present invention. FIG. 1 shows a syringe barrel 1 and a gasket 2 used in carrying out the present invention.
3 shows a plunger rod 3 having a Syringe barrel 1
A plug 5, which is a packing material for filling and sealing the barrel tip 4, is fitted into the barrel tip 4 at the tip, and the bottom surface 6 of the cap 5 is aligned with the inner surface 7 of the front end of the syringe barrel 1, and when the drug solution a is filled. Reference numeral 8 denotes a mounting cylinder having a needle attachment part 9 at its tip, which prevents the drug solution a from entering the cylinder tip 4, and is fixed to the cylinder tip 4 while holding the stopper 5. 10 is a cap. The plunger rod 3 and the gasket 2 made of soft synthetic resin are screwed together and can be separated. Next, to explain the method of the present invention for filling the syringe barrel 1 with the drug solution a, as shown in FIG. Then, a predetermined amount of the chemical solution a is injected from the rear end opening using the nozzle b of the dispenser. At this time, bubbles are often generated on the surface of the drug solution a in the syringe barrel 1.

Next, as shown in FIG. 2B, the holding frame 12 holding the hollow thin tube 11 is placed in the rear end opening of the syringe barrel 1 with the guide hole 13 formed in the groove aligned with the holding frame 12, and the tip of the hollow thin tube 11 is inserted. Insert it along the inner surface of the syringe barrel 1 to a position slightly away from the surface of the drug solution so as not to contact the air bubbles on the surface of the drug solution a in the syringe barrel 1. Next, as shown in FIG. 2C, the plunger rod 3 with the gasket 2 at its tip is inserted into the syringe barrel 1 through the guide hole 13 of the holding frame 12 until the tip of the gasket 2 reaches the tip of the hollow tube 11. After the air in the syringe barrel 1 was removed through the hollow tube 11, the hollow tube 11 was removed. In the above embodiment, the insertion length of the hollow thin tube 11 is the same as that of the syringe barrel 1.
The position of the surface of the drug solution a in the syringe barrel 1 determined by the predetermined amount of the drug solution a to be filled into the syringe barrel 1 is measured, and the holding frame 12 is locked to the rear end of the syringe barrel 1 when the hollow thin tube 11 is inserted. It was adjusted in advance so that it would not be inserted beyond a predetermined position. Further, the insertion position of the plunger rod 3 with the gasket 2 is such that the protrusion 14 formed at the rear end of the plunger rod 3 is inserted into the guide hole 1 of the holding frame 12.
The distal end surface of the gasket 2 is not inserted beyond the distal end of the hollow thin tube 11 by being locked to a stepped portion 15 provided around the hollow tube 11.

As described above, if the position of the hollow capillary tube 11 is not slightly separated from the surface of the filled chemical solution a, air bubbles and the drug solution a will overflow through the hollow capillary tube 11 due to the insertion of the gasket 2, and the drug solution a will also leak into the hollow capillary tube 11. Due to the capillary phenomenon on the outer surface of the gasket 2, the drug solution a enters between the gasket 2 and the inner surface of the syringe barrel 1, and not only is it impossible to fill the syringe barrel 1 with a predetermined amount of the drug solution a, but the drug solution a also reaches the circumferential surface of the gasket 2. When leakage occurs, it becomes impossible to distinguish it from leakage at the gasket 2.

As is clear from the above description, in accordance with the present invention, after the drug solution is injected into the syringe by holding the syringe vertically with the rear end opening of the syringe closed with a stopper facing upward,
Insert the hollow thin tube from the rear end of the syringe barrel along its inner surface to a position slightly away from the drug liquid level to communicate between the inside and outside of the syringe barrel, then insert the plunger rod with a gasket at the tip, and insert the plunger rod with a gasket at the tip. Since the air in the syringe is removed by entering the tip of the thin tube, the drug solution does not overflow or enter the gasket periphery during this air purge operation, making it possible to reliably fill the specified amount of drug solution, making it more expensive. The present invention has the effect of providing a method for manufacturing a syringe filled with a medicinal solution, which can be filled without waste even if the drug solution is large, thereby reducing the cost of the product.

[Brief explanation of drawings]

1 and 2 show an example of the implementation of the present invention. FIG. 1 is a partially cutaway plan view of a syringe barrel and a plunger rod with gasket used in the embodiment, and FIG. FIG. 3 is a diagram showing a manufacturing process using the syringe shown in the figure. 1... Syringe barrel, 2... Gasket, 3... Plunger rod, 8... Syringe needle mounting barrel, 11... Hollow tube,
a...Medical solution.

Claims (1)

[Claims] 1. In a method for manufacturing a syringe filled with a drug solution, in which the syringe barrel for the syringe needle at the tip of the syringe barrel is closed and the drug solution is filled from the rear end of the syringe barrel, the rear end of the syringe barrel with the syringe barrel closed with a stopper. Hold the syringe vertically with the opening upward, inject the drug into the syringe through the rear opening, then insert the hollow tube from the rear end of the syringe along the inner surface of the syringe to a position slightly away from the surface of the drug and inject. The inside of the cylinder and the outside of the syringe are fixed in communication, and then a plunger rod with a gasket at the tip is inserted through the rear opening of the syringe, and the gasket tip is advanced to the position of the tip of the hollow tube to expel the air in the syringe. A method for manufacturing a syringe filled with a drug solution, which comprises removing the hollow tube after the liquid is removed.