JPH10201844A - Cylinder for syringe, production thereof and production of lubricant thin layer based on silicone oil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the mixture of silicone oil into medicine by coating the inner peripheral surface of cylinder for syringe with silicone oil and integrally forming a lubricant thin film based on silicone oil through either of or both of heating and pressurizing. SOLUTION: A robot device is operated and silicone oil is applied to the outer peripheral surface of projecting part 3a on the male metal die of opened metal die by an oil applying device. The area of application can be the outer peripheral surface of column, a top end surface 3c or the entire outer peripheral surface of projecting part 3a including a pin part 3b or can be a section except for the pin part 3b and the top end surface 3c as well. After application, the die is closed and a melted mixed resin is injected and molded by an injection molding machine. This resin is molded while strongly pressing the silicone oil on the outer surface of projecting part 3a at the male metal die, and a lubricant thin layer 2a based on silicone oil is integrally formed on the inner surface of cylinder 1 for syringe. Since the melted mixed resin is kept higher than a sterilizing temperature, sterilization is simultaneously performed and the fixture of silicone oil can be attained as well.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a syringe cylinder in which a thin layer of lubricating oil derived from silicone oil is integrally formed on the inner peripheral surface of the cylinder, and a method of manufacturing the same.

[0002]

2. Description of the Related Art Recently, disposable medical devices have become very popular at medical sites due to problems of hygiene, safety, and human labor. It is the best. Conventionally, glass cylinders have been used for syringes.However, when the use of disposable syringes for drug injection has become urgent, the use of resin cylinders, especially polypropylene and polycarbonate cylinders, has been considered. Have been. In the case of a glass cylinder, of course, when a rubber sliding body is used, in the case of a resin cylinder, silicone oil is applied to the inner peripheral surface of the cylinder cylinder and the rubber sliding body attached to the tip of the piston is smooth. Must slide.

However, since it has been pointed out in the United States that silicone oil may cause damage when it enters the human body, the amount of silicone oil applied is according to the Ministry of Health, Labor and Welfare Notification No. 442, and the disposable type is a small syringe with a capacity of 5 ml or less. Then 8m
It is strictly specified to be less than 15 g / piece, and even large syringes are less than 15 mg / piece. However, the application of silicone oil
Since a cotton swab or sponge is impregnated with silicone oil (2) and manually performed one by one, not only is it easy to apply unevenness, but also apply to the bottom (1b) of the cylinder (1) as shown in FIG. The accumulated silicone oil (2) accumulates, and there is also a problem that the accumulated silicone oil (2) and a thick-flowing portion having fluidity caused by the uneven coating are mixed with the injection solution and injected.

[0004] Furthermore, the most important thing in the manufacture of medical devices is that the final product is free from bacteria and also cytotoxicity causing infectious diseases, such as endotoxin generated from the dead body of Gram-negative bacteria. Is required. Therefore, the molded cylinder (1) is frequently sterilized and washed with ultrapure water in each step, and requires a great deal of labor to minimize the adhesion of bacteria. In the conventional method, even if using sterilized silicone oil and a cylinder (1) almost completely disinfected, and paying attention to the clothes and others of workers in a clean room where there is almost no bacteria,
And no matter how much attention is paid to the application operation, the adhesion of bacteria is inevitable as long as the application operation is performed manually. Once attached, the bacteria grow at the site of attachment. As the number of bacteria increases (especially on the surface coated with silicone oil) due to this growth, even if sterilized after the application operation, the number of bacteria that die by this sterilization operation increases, and the probability of endotoxin adhesion generated from the large number of dead bodies also increases. Of course it will increase. In addition, even if the bacteria increased by the growth are sterilized afterwards, there is a possibility that the number of bacteria that escape from the bacteria may increase. In addition, there is a problem in that the work is performed manually and not only is the product uneven, but also the work efficiency is extremely poor.

[0005]

The first object of the present invention is to provide an extremely thin lubricating layer derived from silicon oil integrally formed on the inner peripheral surface of a cylinder, and to mix silicon oil into a chemical solution. Is in the development of a revolutionary syringe cylinder that is extremely low compared to the conventional example,
Secondly, development of a method for manufacturing a cylinder or a thin lubricating layer of a syringe capable of efficiently producing the cylinder having the lubricating thin layer or the lubricating thin layer while suppressing bacterial growth or maintaining an aseptic condition. It is in.

[0006]

Means for Solving the Problems "Claim 1" is based on the fact that "the silicone oil (2) is applied to the inner peripheral surface of the cylinder (1) of the syringe by heating and / or pressurizing after applying the silicone oil (2). The lubricating thin layer (2a) is integrally formed. ''
It is characterized by things.

[0007] According to this, the inner peripheral surface (1a) of the cylinder (1) is simply coated with the silicone oil (2) as in the prior art.
When the rubber sliding body (1d) attached to the tip of the piston (1c) is moved, a part of the rubber sliding body (1d) adheres to it and is thickly painted, rubbing the part that maintains fluidity. Unlike those that are taken and mixed into the injection solution,
In the product of the present invention, the lubricating thin layer (2a) derived from silicone oil forming the lubricating layer is formed not only on the inner peripheral surface (1a) of the cylinder (1) but also on the bottom surface (1b) and the projection (1e) for injection needle mounting. Since it is integrally formed on the entire inner peripheral surface including the inner peripheral surface (1f), even if the rubber sliding body (1d) attached to the tip of the piston is moved in the cylinder (1), The lubricating thin layer (2
a), of course, the lubricating thin layer (2a) on the bottom surface (1b) and the inner peripheral surface (1f) of the injection needle mounting projection (1e) hardly peels off, and there is almost no mixing with the injection solution. And extremely sanitary.

In this case, the material of the cylinder (1) is generally a resin. Further, as the silicone oil (2), only one kind, polydimethylsiloxane, which will be described later, is approved in the current Pharmaceutical Affairs Law, but it goes without saying that the invention is not limited to this. The lubricating thin layer (2a) is formed only by heating, only by pressing, or by using both heating and pressing. The heating and pressurizing methods are generally performed by injection molding as described below, but are not limited thereto.

The second aspect of the present invention relates to a rubber sliding body (1d) in which a region for forming a thin lubricating layer (2a) is mounted on the tip of a piston (1c).
Is the inner circumferential surface (1a) of the cylinder (1) that slides. '' According to this, the portion where the lubricating thin layer (2a) derived from silicone oil is formed is a rubber sliding body ( Since only the cylinder inner peripheral surface (1a) of the cylinder (1) necessary for the sliding of 1d) is used, the application area of the silicone oil (2) can be minimized,
This leads to a reduction in the consumption of silicone oil (2), which in turn improves safety.

[0010] Claim 4 is an example of a method for manufacturing the cylinder (1) for the syringe.
Silicon oil (2) is applied to the surface of the convex portion (3a), and then, after clamping, the resin (13) is injected into the mold cavity (4), and the cylinder (3) formed of the resin (13) is formed. 1) integrally forming a lubricating thin layer (2a) derived from silicone oil generated by heating and pressurizing during injection molding on the inner peripheral surface ".

According to this, a male mold for forming a cylinder is provided.
The surface of the convex portion (3a) of (3) [In this case, not only the outer peripheral surface but also the outer peripheral surface of the tip surface (3c) and the pin portion (3b)]. 』
By simply adding the step of applying silicone oil (2) to the cylinder, it is possible to form a cylinder (1) in which the lubricating thin layer (2a) derived from silicone oil is firmly and integrally formed on the entire inner peripheral surface . Further, since this lubricating thin layer (2a) is formed by applying pressure and heating (for example, the molten resin temperature at the time of filling is 200 to 350 ° C., and the filling pressure is 300 to 2000 kgf / cm ² ), the conventional coating method is used. The thickness can be made much thinner, and the amount of silicone oil (2) applied can be minimized. The mechanism that produces such an effect will be described later.

Since the injection molding is performed after the silicone oil (2) is applied, even if the silicone oil (2) is
Silicone oil even if bacteria are attached when applying
Immediately after the application of (2), injection molding is performed at high temperature and high pressure, so that the adherent bacteria are completely killed shortly after they grow, and the safety can be improved compared to the conventional example. Because of the injection molding, the inner diameter of the cylinder (1) includes the lubricating thin layer (2a), and unlike the case of applying silicone oil (2) after molding, the dimensional accuracy of the cylinder (1) inner diameter is extremely high Become.

[0013] Claim 5 is an example of a method for producing a thin lubricating layer (2a) for a cylinder of a syringe, which is used for forming a thin lubricating layer (2a) having at least the same shape as the inner peripheral shape of a cylinder (1) for a syringe. Type (3
Silicone oil (2) is applied to the surface of the convex portion (30a) of (0), and then the convex portion (30a) is inserted into a cylinder (1) for a syringe and heated or pressurized or heated / heated, The resulting thin lubricating layer (2a) derived from silicon oil is integrally formed on the inner peripheral surface of the cylinder (1). "

According to this, the already formed cylinder (1)
Silicon oil is applied to the entire inner peripheral surface of the cylinder (1) including the inner peripheral surface (1a), the bottom surface (1b) and the inner peripheral surface (1f) of the injection needle mounting projection (1e). The lubricating thin layer (2a) of origin can be integrally formed. Also in this case, the cylinder
The material of (1) is generally resin and silicone oil (2)
Not only polydimethylsiloxane but also the lubricating thin layer (2a) is formed only by heating or only by pressing, or by using both heating and pressing. The heating and pressing methods are not limited.

Claim 6 relates to the cylinder (1) of the syringe.
In another example of the manufacturing method of `` Silicon oil (2) is applied to the surface of the convex part (3a) of the male mold (3) for forming a cylinder, then the mold is closed, and the resin is poured into the mold cavity (4). ), And integrally form a lubricating thin layer (2a) derived from silicone oil on the inner peripheral surface of the cylinder (1) made of resin.After opening the mold, a male mold (3)
Printing on the surface of the cylinder (1) attached to the surface. "

According to this, in addition to the above-mentioned case, a male mold
Since printing is performed on the surface of the high temperature cylinder (1) attached to (3), the printing ink can be dried quickly and the printing process can be shortened. Even if there is adhesion, it is instantaneously killed by heat, so that even in this step, the growth of bacteria can be suppressed or an aseptic state can be maintained, which is very hygienic.

Claims 3 and 8 relate to a limitation on the silicone oil (2), wherein "the silicone oil (2) is polydimethylsiloxane, has a viscosity of 500 to 30,000 centistokes, and a coating amount of 0. 0.001 to 0.05 g /
100 cm ² ".

Within the above range, the lubricating thin layer (2a) integrally and firmly formed on the inner peripheral surface (1a) of the cylinder (1) formed by injection molding is uniform and slidable. Is formed with high reproducibility without impairing the image quality and without fogging. As the silicone oil (2), any kind and any kind of silicone oil can be used in principle, but only polydimethylsiloxane is currently approved by the Ministry of Health and Welfare of Japan. The structural formula of polydimethylsiloxane is shown below. _{(CH 3) 3 -O- [Si} (CH 3) 2 -0] n -Si-
(CH ₃ ) ₃

[Claim 7] is a projection of silicone oil (2).
(3a) Regarding the limitation of the application area to (30a), `` the application area of silicone oil (2) is the cylindrical outer peripheral surface (3
d) and (30d) only, according to which the portion of the lubricating thin layer (2a) derived from silicone oil has the cylinder (1d) necessary for sliding the rubber sliding body (1d). ) Inner circumferential surface of cylinder
Since only (1a) is used, the application area of the silicone oil (2) can be minimized, which leads to a reduction in the consumption of the silicone oil (2) and, consequently, an increase in safety.

[0020]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. FIG. 1 shows a general injection molding machine (A) for producing a cylinder (1) of the present invention, in which a nozzle (7) of an injection cylinder (6) is connected to a female mold (5). Screw in the injection cylinder (6)
(8) is disposed so as to rotate and slide back and forth. An injection cylinder (9) and a drive unit (10) are connected to the screw (8), and the screw (8) is slid back and forth by the injection cylinder (9), and is then moved through a gear mechanism (11). The screw (8) is rotated by the drive unit (10). A hopper (12) is provided at the rear end of the injection cylinder (6) so as to continuously supply the raw material resin (13). A heater (14) is wound around the injection cylinder (6), and the raw material resin
(13) is heated and melted.

The main components of the mold (K) of the embodiment shown in the figure are a male mold (3), a female mold (5), and a protruding cylinder (15). A convex portion (3a) for forming the inner surface shape of the cylinder is projected, and a concave portion (5a) for forming the outer surface of the cylinder (1) is formed in the female mold (5) correspondingly. Have been.

(R) is a robot device, which is provided alongside the injection molding machine (A), for example, an oil application device (16), a printing device
(17) and the take-out device (20) can be moved to a predetermined position. Although a manual operation may be used instead of the robot device (R), it is preferable that at least the extraction device (20) use the robot device (R). The entire apparatus is generally installed in a clean room where the number of bacteria is strictly controlled.

Resin raw material (13) used for cylinder (1)
It is necessary to meet various conditions stipulated by the Pharmaceutical Affairs Law, such as water permeability, transparency, and heat resistance, depending on the application, and thus, for example, polypropylene, polycarbonate, aromatic polyolefin and the like are used.

Next, the operation of the present invention will be described. First, the robot device (R) is activated, and the oil application device (16)
An appropriate amount of silicone oil (2) is applied to the outer peripheral surface of the convex portion (3a) of the male mold (3) of the mold (K) that has been opened. The coating area is the convex part including the cylindrical outer peripheral surface (3d), the tip surface (3c) and the pin part (3b).
The entire outer surface of (3a) or a portion excluding the pin portion (3b) or the tip surface (3c) may be applied, but at least the outer peripheral surface (3d) of the column is applied.

The method of applying the silicone oil (2) is not particularly limited, and in this embodiment, the oil applying device (16) is used.
Use a robotic device (R) like silicone oil (2)
A cylindrical cloth or paper impregnated with, a sponge (16a) or the like is used to surround and press the convex portion (3a) and press the silicone oil on the outer peripheral surface of the convex portion (3a) including at least the cylindrical outer peripheral surface (3d). Apply 2). When silicone oil (2) is applied, the mold is closed and the mold
A mold cavity (4) is formed in (K).

On the other hand, the raw material resin (13) is put into the hopper (12), and the driving unit (10) is operated to rotate the screw (8). With the rotation of the screw (8), the raw material resin (13)
In 4), the mixture is heated to, for example, 200 to 350 ° C., melted and kneaded, and stored at the tip of the injection cylinder (6). At the same time, the screw (8) gradually retreats, and when the metering of the molten kneaded resin stored at the tip of the injection cylinder (6) is completed, the injection cylinder (9) is operated to project the screw (8) forward. Let
Put the metering resin at the tip of the injection cylinder (6) into the mold (K) for 300 to 20
Inject at 00 kgf / cm ² .

The injected melt-kneaded resin (13) is supplied to a mold (K).
Mold cavity passing through the runner (18) and gate (19)
(4) is press-fitted at high speed and high pressure. The melt-kneaded resin (13) press-fit into the mold cavity (4) is the convex part (3a) of the male mold (3).
The mold cavity (4) is instantaneously filled while strongly pressing the silicone oil (2) applied to the outer surface of the mold. At this time, the silicon oil (2) instantaneously rises to the temperature of the melt-kneaded resin (13), and at the same time, is evenly spread on the surface of the projection (3a) and adheres to the inner peripheral surface of the melt-kneaded resin (13). Thereafter, the melt-kneaded resin (13) solidifies to form a cylinder (1), and a thin lubricating layer derived from silicon oil is formed on at least the inner peripheral surface (1a) of the cylinder.
(2a) is integrally formed. The forming range of the lubricating thin layer (2a) corresponds to the application area of the silicone oil (2).

In this step, the mold (K) is also melt-kneaded resin (13)
Also, since the temperature is generally maintained at a temperature higher than the sterilization temperature, there is no possibility that bacteria adhere to the projections (3a) or the cylinder (1) and multiply during this injection molding. Even if it adheres, it will die instantly due to high temperature, so it will not only adhere or proliferate bacteria, but also minimize the generation of endotoxins, etc. that cause infectious diseases, or decompose itself throughout the manufacturing process of the cylinder (1) The safety can be greatly improved compared to the conventional manufacturing method.

Here, the lubricating thin layer (2
The estimated mechanism of the formation process of a) will be described. No matter how precisely the surface of the cavity forming the mold cavity (4) is polished or otherwise processed, extremely fine irregularities on the order of submicrons (for example, 0.5 to 0.02 μm) remain with the current technology. . Now, silicone oil (2) on the convex part (3a)
When the silicone oil (2) is applied, the silicon oil (2) having a high viscosity does not enter the recess on the submicron level remaining on the surface of the projection (3a) due to its surface tension. (See FIG. 2 (b).) Therefore, when injection molding is performed at a high temperature and a high pressure as described above, the silicone oil (2) is pressed and spread on the surface of the convex portion (3a) by the high pressure of the injection resin, and at the same time, a part of the silicon oil (2) is spread. Is pressed into the recess, and a lubricating thin layer (2a) having irregularities is uniformly formed on the entire outer peripheral surface including at least the cylindrical outer peripheral surface (3d) of the convex portion (3a), and this is formed at least in the cylinder of the cylinder (1). Perimeter (1a)
And is integrally attached to the inner peripheral surface including. As a result, as shown in FIG. 12, a thick portion (2b) of a submicron order (for example, 0.5 to 0.02 μm) is formed on the inner peripheral surface of the thin lubricating layer (2a). The sub-micron thick island-shaped portion (2b) spreads uniformly in an island shape as a whole, and most of the smooth sliding of the rubber sliding body (1d) is assisted. As a result, the application amount of the silicone oil (2) is extremely small as compared with the conventional example.

This lubricating thin layer derived from silicone oil (2a)
Is not simply a coated state that can be easily wiped off partly or entirely with a cloth or the like.
It is in a state of being firmly and integrally formed on the inner peripheral surface (1a) of the cylinder of (1).

Cylinder with thin lubricating layer (2a)
When the molding of (1) is completed, the mold is opened to expose the cylinder (1) attached to the male mold (3) to the outside, and then the robot device (R) is operated to print the printing device (17). Is moved directly above the cylinder (1), the printing pad (17a) of the printing device (17) is lowered, and the printing pattern applied on the printing pad (17a) is applied to the surface of the cylinder (1). Transfer printing. Even at this point, the surface of the cylinder (1) has maintained a sufficient sterilization temperature,
Bacterial growth is prevented, and the printed ink dries quickly, allowing for quick removal. When printing is completed, the printing pad (17a) is lifted and separated from the cylinder (1), and then the protruding device (15a) is operated to protrude the protruding cylinder (15).
And the cylinder (1) fitted to the projection (3a) is detached. Thereafter, the robot device (R) is operated to move the unloading device (20) to a position immediately above the runner portion (21) of the injection molded product, and then the unloading device (20) is lowered to lower the runner portion (2).
Grab 1) and remove it from the mold (K). The above operations are repeated to perform mass production of the syringe cylinder (1) under aseptic conditions.

FIGS. 9 and 10 show a case where a lubricating thin layer (2a) is formed by using a molded cylinder (1). First, a mold (30) for forming a lubricating thin layer (2a) having substantially the same shape as the inner peripheral shape of at least the cylinder (1) for a syringe is prepared. Since the lubricating thin layer (2a) requires the inner peripheral surface (1a) of the cylinder (1), the forming die (30) matches only the inner peripheral surface (1a) of the cylinder (1). It suffices if it has the following shape In the illustrated embodiment, an example having up to the pin portion (30b) is described.

First, silicone oil (2) is applied to the surface (at least the outer peripheral surface (30d) of the cylinder) of the projection (30a), and then the projection (30a) is inserted into the cylinder (1) for a syringe. Then, heating or pressurizing or heating / heating is performed, and the resulting lubricating thin layer (2a) derived from silicon oil is integrally formed on the inner peripheral surface of the cylinder (1). As a pressing method, a female mold (not shown) may be fitted to the outside of the cylinder (1) to apply pressure, and the method is not limited. Heating method is convex (3
0a), a heater (not shown)
The projection (30a) may be heated by heat transfer from (30).

Also in this case, the inner circumference including at least the inner circumferential surface (1a) of the preformed cylinder (1), and in some cases, the bottom surface (1b) and the inner circumferential surface (1f) of the injection needle mounting projection (1e). A thin lubricating layer (2a) derived from silicone oil can be integrally formed on the entire surface.

Example 1 Next, the results of experiments on the amount of silicone oil (polydimethylsiloxane) applied, slidability and appearance are shown. Cylinder oil was applied to the protrusions, and injection molding was performed as described above using polycarbonate as a raw material resin. When a thin lubricating layer is formed on the inner peripheral surface of the cylinder, the slipperiness of the butyl rubber sliding body attached to the tip of the syringe piston is remarkably improved.However, if the amount of application to the convex portion is too large, the cylinder becomes cloudy. This results in poor appearance. Conversely, if the coating amount is too small, the appearance is good but the slipperiness is impaired. The relationship between the amount of silicone oil applied and the slidability and appearance was examined as follows. (Example 2) Next, the results of experiments on the viscosity of silicone oil (polydimethylsiloxane), slidability and appearance will be described. From the above, when the silicone oil is polydimethylsiloxane as an area that clears both slidability and appearance,
It can be seen that the viscosity is 500 to 30,000 centistokes and the coating amount is 0.001 to 0.05 g / 100 cm ² .

[0036]

According to the present invention, a thin lubricating layer derived from silicon oil is integrally formed on at least the inner peripheral surface of the cylinder in which the rubber sliding body mounted on the tip of the piston slides. Even if the rubber sliding body is moved, there is almost no peeling of the lubricating thin layer and there is no mixing in the injection solution. In addition, if the silicon oil application area is limited to the cylindrical outer peripheral surface of the convex part, not only the silicon oil application area can be minimized, but also the accumulation of silicon oil unlike the conventional case does not occur, Can increase the quality. Further, according to the method of the present invention, it is possible to form a thin lubricating layer only by applying silicone oil to the surface of the projection, and mass-produce a safe cylinder with very little bacterial adhesion and endotoxin by automation. Becomes possible. In addition, if printing is performed on the surface of the cylinder attached to the male mold after opening the mold, it is possible to shorten the printing process by quickly drying the printing ink and suppress the adhesion and growth of bacteria at the same time. There are advantages.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of an injection molding machine according to the present invention.

2A is an enlarged front sectional view of a main part of the method of the present invention in which silicone oil has been applied to a convex portion in a mold open state. FIG.

FIG. 3 is an enlarged sectional view of a main part in a mold clamping state.

FIG. 4 is an enlarged cross-sectional view of a main part in a middle stage of the kneading molten resin being injected into a mold cavity in a mold clamping state.

5A is an enlarged cross-sectional view of a main part in a state in which a kneaded molten resin is filled in a mold cavity in a mold-clamped state. FIG.

FIG. 6 is an enlarged sectional view of a main part in a single-open state;

FIG. 7 is an enlarged cross-sectional view of a main part in a state where printing is performed on the outer surface of the cylinder after one-sided opening

FIG. 8 is an enlarged sectional view of a main part in a state where the printing completion cylinder is released from the mold.

FIG. 9 is a cross-sectional view of a main part when a ready-made cylinder is to be mounted on a protrusion by another method of the present invention.

FIG. 10 is a cross-sectional view of a main part when a ready-made cylinder is mounted on the protrusion.

FIG. 11 is a partially enlarged cross-sectional perspective view of the inner peripheral surface of the cylinder of the cylinder according to the present invention.

12A is a cross-sectional view of a cylinder in which a thin lubricating layer formed by the method of the present invention is formed on the entire inner peripheral surface. FIG. Sectional view of a cylinder formed only on the surface

13A is a cross-sectional view of a cylinder of a conventional syringe. FIG. 13B is an enlarged cross-sectional view of a part of FIG.

[Explanation of symbols]

 (A)… Injection molding machine (1)… Cylinder (1a)… Cylinder inner peripheral surface (1b)… Bottom (1c)… Piston (1d)… Rubber sliding body (2)… Silicon oil (2a)… Derived from silicon oil Lubricating thin layer (2b)… Submicron thick island

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[Procedure amendment]

[Submission date] April 25, 1997

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Brief description of drawings

[Correction method] Change

[Correction contents]

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of an injection molding machine according to the present invention.

FIG. 2 is a drawing with a further enlarged view of a circled part.
In the present invention, a main part enlarged front sectional view of a state in which silicone oil is applied to a convex portion in a mold open state.

FIG. 3 is an enlarged sectional view of a main part in a mold clamping state.

FIG. 4 is an enlarged cross-sectional view of a main part in a middle stage of the kneading molten resin being injected into a mold cavity in a mold clamping state.

FIG. 5 is a drawing having a further enlarged view of a circled portion.
The main part enlarged cross-sectional view of the state where the kneaded molten resin is filled in the mold cavity in the mold-clamped state

FIG. 6 is an enlarged sectional view of a main part in a single-open state;

FIG. 7 is an enlarged cross-sectional view of a main part in a state where printing is performed on the outer surface of the cylinder after one-sided opening

FIG. 8 is an enlarged sectional view of a main part in a state where the printing completion cylinder is released from the mold.

FIG. 9 is a cross-sectional view of a main part when a ready-made cylinder is to be mounted on a protrusion by another method of the present invention.

FIG. 10 is a cross-sectional view of a main part when a ready-made cylinder is mounted on the protrusion.

FIG. 11 is a partially enlarged cross-sectional perspective view of the inner peripheral surface of the cylinder of the cylinder according to the present invention.

12A is a cross-sectional view of a cylinder in which a thin lubricating layer formed by the method of the present invention is formed on the entire inner peripheral surface. FIG. Sectional view of a cylinder formed only on the surface

FIG. 13 has a further enlarged view of the circled part.
Sectional view of the cylinder of a conventional syringe in terms of surface

[Description of Signs] (A) Injection molding machine (1) Cylinder (1a) Inner peripheral surface of cylinder (1b) Bottom surface (1c) Piston (1d) Rubber sliding body (2) Silicon oil (2a) ): Thin lubricating layer derived from silicon oil (2b): Submicron thick island-shaped part

Claims (8)

[Claims] The present invention is characterized in that a thin lubricating layer derived from silicon oil generated by heating and / or pressurizing after applying silicone oil is integrally formed on an inner peripheral surface of a cylinder of a syringe. A syringe cylinder. 2. The syringe cylinder according to claim 1, wherein the region in which the thin lubricating layer is formed is the inner peripheral surface of the cylinder on which the rubber sliding body mounted on the tip of the piston slides. 3. The silicone oil is polydimethylsiloxane, has a viscosity of 500 to 30,000 centistokes, and has a coating amount of 0.001 to 0.05 g.
Syringe cylinder according to claim 1 or 2, characterized in that a / 100 cm ^2. 4. A silicone oil is applied to the surface of a convex portion of a male mold for forming a cylinder, and then, after clamping, a resin is injected into a mold cavity. A method for manufacturing a cylinder of a syringe, wherein a thin lubricating layer derived from silicone oil generated by heating and pressurizing during injection molding is integrally formed. 5. Applying silicone oil to at least the surface of the protrusion of the lubricating thin layer forming mold having substantially the same shape as the inner peripheral shape of the syringe cylinder, and then inserting the protrusion into the syringe cylinder and heating Alternatively, a method for producing a lubricating thin layer for a cylinder of a syringe, wherein the lubricating thin layer derived from silicon oil is formed integrally on the inner peripheral surface of the cylinder by pressurizing or heating / heating. 6. A silicone oil is applied to the surface of a convex portion of a male mold for forming a cylinder, and then, after clamping, a resin is injected into a mold cavity, and a resin is formed on an inner peripheral surface of the cylinder. A syringe that is characterized by integrally forming a lubricating thin layer derived from silicon oil generated by heating and pressurizing during injection molding, and after opening the mold, printing on the surface of the cylinder attached to the male mold. Manufacturing method of cylinder. 7. The method for manufacturing a cylinder of a syringe according to claim 4, wherein the silicone oil is applied only on the outer peripheral surface of the cylindrical portion of the projection. 8. The silicone oil applied to the surface of the convex part of the male mold is polydimethylsiloxane, the viscosity of which is 500 to 30,000 centistokes,
Method for producing a syringe cylinder according to claim 4 in which the coating amount, characterized in that it is 0.001-0.05 grams / 100 cm ^2.