JPH0562547B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention provides flexible fluids for accommodating intravenous infusions such as carbohydrate infusions, electrolyte infusions, plasma expanders, osmotic diuretics, fat emulsions, and high-calorie infusions. The present invention relates to a plastic container for infusions, and more specifically, it relates to a plastic container for infusions that has extremely good dripping properties during so-called "natural dripping," in which the body is deformed to inject an infusion without supplying air to the inside. be. [Prior Art] In recent years, the use of plastic containers for infusions has rapidly progressed due to their advantages such as not breaking when dropped and being lightweight. In particular, the natural drip type, which takes advantage of the flexibility of plastic material and deforms the body to administer the drip, is often used. This is because, in the case of natural dripping, dripping can be performed without supplying air into the container, and therefore, there is a sanitary advantage in that there is no fear of germs entering the container. The above-mentioned natural drip type plastic containers for infusions include bag type containers (for example, Japanese Patent Publication No. 61-38705
) and bottle format (e.g. JP-A-62-
227355 etc.). [Problem to be Solved by the Invention] In the former, the bag body is made by heat-sealing the entire circumference except for the insertion part of the mouth part, which is made of two films or a tube-shaped film body, by high-frequency heating. Then, a tube made of hard synthetic resin is inserted into the non-sealed part and heat-sealed, so manufacturing is complicated and the seal between the tube and the bag can be ruptured during sterilization and pressurization. It had the problem of being packaged. The latter has a bottom and stands on its own, and its body has an elliptical cross-sectional shape and is straight in the vertical direction, making it easy to deform concavely when the body is under negative pressure. It is designed to be able to handle dripping. However, this bottle-type bottle has a problem in that when the dripping rate is measured when the dripping is completely completed, it is 50% lower than the amount of the originally filled infusion solution. In view of the above points, the present invention has the following objects. Good natural dripping properties, minimizing the final amount of remaining infusion fluid. It is easy to manufacture and can be formed in one piece when manufacturing the mouth part. Welding of the plug to the mouth part must be easy and complete. It is heat resistant and does not deteriorate during sterilization. Must be transparent enough to detect foreign objects inside. [Means for Solving the Problems] In order to achieve the above object, the present invention is configured as follows. In other words, it is a plastic container in which a body with an elliptical cross-sectional shape and a mouth portion whose other end is welded and sealed with a stopper are integrally formed by blow molding. The face wall and both side walls have a convex shape toward the center of the body, and are configured with at least a two-layer structure of an inner surface layer and an outer surface layer, and the elastic modulus ratio (T × E) of the inner surface layer and the outer surface layer. The plastic forming the outer surface layer has a flow start point of 115℃ to 170℃ and a total light transmittance of 85% or more with a wall thickness of 0.5mm. The plastic container for infusions is characterized by a flow start point of 110°C or lower. The elastic modulus ratio in the present invention refers to tensile elastic modulus (JISK
7113) It is the product of EKg/mm ² and wall thickness Tmm, and its unit is expressed in Kg/mm. The elastic modulus ratio of the plastic container for infusion of the present invention is such that the sum of the inner surface layer and the outer surface layer is 5 to 12 kg/mm, more preferably 5 to 10 kg/mm. If the elastic modulus ratio exceeds 12 Kg/mm, the dripping rate will decrease and the natural dripping properties will be poor, whereas if it is less than 5 Kg/mm, it will deform during steam sterilization. In the present invention, the flow starting point is the point at which the flow is 2.
It refers to the temperature when the temperature reaches mm ² /scc. The total light transmittance refers to the ratio between the amount of incident light and the total amount of light transmitted at a wavelength of 420 nm as defined in JISK6714. In the plastic container for infusions of the present invention, the inner surface layer is composed of a plastic whose flow initiation point is less than 110°C, such as ethylene vinyl acetate copolymer, linear low density polyethylene, linear medium density polyethylene, ionomer, etc. Resin etc. are suitable.
In addition, the outer surface layer is made of plastic with a flow initiation point of 115 to 170°C, a wall thickness of 0.5 mm, and a total light transmittance of 85% or more, such as ethylene propylene containing 2 mol% to 20 mol% ethylene. Random copolymers, ethylene-propylene block copolymers, polypropylene homopolymers, and propylene random copolymers containing very small amounts of comonomers are suitable. The plastic container for infusion according to the present invention has a structure of at least two layers, an inner surface layer and an outer surface layer, and a gas barrier layer, adhesive layer, or other intervening layer is disposed between the inner surface layer and the outer surface layer. It is also possible to intervene with a thickness not exceeding 20% of the wall thickness. Furthermore, the plastic container for infusion of the present invention is not limited to intravenous injection, but can be used in a wide range of applications for administering liquid subcutaneously, intravascularly, intraperitoneally, etc. DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be explained below using drawings to facilitate understanding of the present invention. 1 is a plastic container for infusion. A plastic container 1 for infusion is formed of a body 2 and a mouth 3. The body portion 2 includes a front wall 4, a rear wall 5, and side walls 6, 6 forming a hollow portion.
It is composed of an upper wall 7 forming an upper portion, and lower walls 8, 8 forming a lower portion. The body part 2 and the mouth part 3 have inner surface layers 2a and 3a as shown in FIG.
It has a two-layer structure including outer surface layers 2b and 3b. A mouth portion 3 is integrally formed in the center of the upper wall 7. The mouth portion 3 is sealed by heat-welding a plug body 9 containing a rubber stopper at its upper end and an inner surface layer 3a at the flanges 3' and 9'. At the center of the lower wall 8, a hanging tool 10 having a hanging hole 10a is integrally provided. The front wall 4, the rear wall 5, and the side walls 6, 6 are convex toward the center of the body 2. 3 shows the outer shape of a cross section at the center of the body 2, and FIG. 4 shows the outer shape of a cross section taken along the line AA in FIG. The container 1 has a body part 2 and a mouth part 3 which are integrally formed by blow waveforms, except for a stopper 9, and an infusion solution is filled from the mouth part 3, and then the mouth part 3 is sealed with a stopper 9. The plug body 9 and the mouth part 3 are sealed by heating and melting the welded surfaces of the flange parts 3a and 9a by contact with a heating plate.
They are compressed and welded together. Thereafter, the container 1 is placed in a pressurized sterilization tank at 115° C. for a certain period of time, and the container 1 is placed in a sterilization tank for a plastic container for infusion for a certain period of time to sterilize the infusion. [Function] The present invention, constructed as described above, has good natural dripping properties, particularly minimizes the amount of infusion remaining at the end, and also allows the mouth and body to be integrally formed, making the stopper Welding can be easily and completely achieved, and there is no deformation of the container due to sterilization. The details of why the plastic container for infusion according to the present invention achieves a good dripping rate are not known, but the reason is that the front wall, rear wall, and both side walls of the body are all convex toward the center of the body. It has been found that this is due to the fact that the container, which has a specific shape with an elliptical cross-sectional shape, is made of plastic having a specific elastic modulus ratio. Particularly surprising is that a much better dripping rate can be obtained than in the conventionally known plastic containers for infusions, which have a body shape in which the circumferences of the cross-sections of the body are substantially all the same. It has been found. [Example] Using the plastic materials shown in Table 1, the first
Examples 1 to 4 of the structure shown in Table 2, in which the front wall 4, rear wall 5, and both side walls 6, 6 of the body section 2 shown in FIGS. 4 to 4 are convex toward the center of the body section. It was obtained by blow molding the containers of Comparative Example 1 and Comparative Example 2. In addition, a container of Comparative Example 3 was obtained with the same layer structure as in Example 1, but whose body had an oval cross-sectional shape as shown in FIG. 6 and was linear in the vertical direction. Note that each of the above containers weighed 20 g. 75% of the total capacity in each container of Examples and Comparative Examples
The container was filled with 500 c.c. of infusion solution, the mouth was sealed with a stopper, and the container was sterilized by placing it in a pressurized sterilization tank at 115°C for 30 minutes. ), the appearance was measured, and the following drip test was conducted. The results are shown in Table 2.

[Table] of.

〔Effect of the invention〕

Since the present invention is constructed as described above, the natural dripping property is good, and in particular, the amount of infusion remaining at the end can be minimized, and the mouth part and the body part can be formed integrally, and the stopper can be welded. can be easily and completely obtained, and there is no deformation of the container due to sterilization.

[Brief explanation of drawings]

Fig. 1 is a front view of the plastic container for infusion according to the present invention, Fig. 2 is a side view of the same, and Fig. 3 is B of Fig. 1.
- A diagram showing the external shape of part B, Figure 4 is A of Figure 1
- A diagram showing the external shape of part A, Figure 5 is C in Figure 1.
FIG. 6 is a perspective view showing a conventional example. 1... Plastic container for infusion, 2... Body, 2a
... trunk inner surface layer, 2b... trunk outer surface layer, 3... mouth, 3a... mouth inner surface layer, 3b... mouth outer surface layer,
4...Front wall, 5...Back wall, 6...Side wall.

Claims (1)

[Claims] 1. A plastic container for infusions in which a body having an elliptical cross-sectional shape and a mouth whose other end is welded and sealed with a stopper are integrally formed by blow molding, and the body has a front wall, a rear wall, and a mouth. Both side walls have a convex shape toward the center of the body, and are configured with at least a two-layer structure of an inner surface layer and an outer surface layer, and the sum of the elastic modulus ratios (T x E) of the inner surface layer and the outer surface layer. is 5~12Kg/mm
The plastic that makes up the outer surface layer has a flow start point of 115℃ to 170℃ and a total light transmittance of 85% or more at a wall thickness of 0.5 mm, and the plastic that makes up the inner surface layer has a flow start point of 115℃ to 170℃. A plastic container for infusion that is characterized by a temperature of 110°C or less.