JPS62127057A - Apparatus for treating body fluids - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] (Field of Application in the Preface) Unreleased jfl includes 1 piece of artificial moss, 2 blood leaf separation and exchange devices, 1 person:
Lungs, humans [liver, blood filtration equipment, etc.]

(Conventional technology) Usually, 1 piece of artificial moss, blood filth separation and exchange device, artificial lung, person
When assembling a body fluid treatment device such as a blood filter device or the like, a polyurethane is filled to fix the end of the hollow fiber housed in the housing, and a cap is placed between the polyurethane and a cap having a flow port for the body fluid. This was done by interposing a silicone rubber gasket and making it fluid-tight using an ultrasonic welder.

FIG. 3 is a schematic view showing changes in the shapes of the gasket 20 and polyurethane 21 during assembly of the above-mentioned body fluid treatment device.

(A) Storage groove 2 for packing 20 formed on the cap side
A packing 20 is interposed between 2 and polyurethane 21 to fix the cap to the housing. At this time, the shapes of the polyurethane 21 and the packing 20 hardly change.

(B) Send ultrasonic waves to bring the cap and housing into fluid-tight contact. At this time, the cap is pressed by the ultrasonic waves and is firmly fixed to the housing, so the gasket 20 is also pressed at the same time as the cap, deforms into an elliptical shape, and presses into the polyurethane 21.

(C) When the body fluid treatment device assembled as described above is sterilized using high-pressure steam, the gasket 20 almost recovers to the shape of (A), and the polyurethane 721
Creep occurred between the packing 20 and the polyurethane 21 because it could not recover to its original shape while being pressed to zero.

(Problems with the prior art) As described above, these polyurethane 21 and packing 2
Depending on the selection of these combinations, polyurethane can undergo double compression set (
creep) was occurring.

This caused liquid leakage due to poor sealing.

(Means for Solving the Problems) Therefore, the present invention has intensively studied the combination of these polyurethanes and the hardness of the packing, and has developed a polyurethane having an appropriate hardness (JIS A hardness of 90° to 99°). By selecting an appropriate material and packing material (JI S-A hardness: 25° to 40°), taking into consideration its hardness and resilience, and using them in combination, it is possible to The present invention also provides a body fluid treatment device that does not cause creep between the urethane and the packing and has particularly excellent liquid tightness.

(Example) Fig. 1 shows a cap 2 and a housing 3 of a body fluid treatment device l.
The assembly state diagram is shown.

A plurality of bundled hollow fibers 4 are housed inside the housing 3, and the ends of the hollow fibers 4 are fixed with polyurethane 5.

On the other hand, the cap 2 has a body fluid communication port 6 formed therein, and a gasket storage groove 7 formed in a position facing the polyurethane 5 filled in the housing 3.

Reference numeral 8 indicates a packing sandwiched between the storage groove 7 and the polyurethane 5.

The material of the gasket 8 is silicone rubber, butadiene rubber, butyl rubber, or other thermoplastic elastomer.

Next, polyurethane and packing having various JIS-A hardnesses are appropriately selected (combination of packing having JIS-A hardness of 25° to 40' and polyurethane having JIS-A hardness of 90° to 99°), and body fluid treatment is performed. An example in which the device is assembled will be described in detail.

Table 1 shows the results of a sealability test after the assembled body fluid treatment device was sterilized using high-pressure steam in the same manner as in the conventional method.

According to the results in Table 1, the sealing performance was very good when packing with a JIS-A hardness of 25° to 400 was used.
When a gasket with a temperature of 0° or more was used, liquid leakage was observed.

Also, when polyurethane having a JIS-A hardness of 88° or less was used, some liquid leakage was observed.

As mentioned above, in the combination of JIS-A hardness 25° to 40o polyurethane and JIS-A hardness 90' to 999 polyurethane, the hardness of the polyurethane is high and the packing has appropriate elasticity and elastic recovery power. When assembling the cap and housing using a welder, as shown in FIG. 2, the gasket 9 pressed together with the cap is
The polyurethane 10 itself cannot be embedded, and the packing 9 itself deforms into a flat state and comes into close contact with the polyurethane lO. (FIG. 2-(A)) Even if high-pressure steam sterilization is performed in this state, almost no creep occurs in the polyurethane, and only the packing 9 itself recovers to an elliptical shape. At this time, the packing 9 can be in close contact with the polyurethane 10 and the storage groove 11, so there is no fear of liquid leakage.

If the JIS-A hardness of the packing is 25 degrees or less, it is difficult to mold the packing itself, and it is too soft to be attached to the cap.

When the JI S-A hardness of the packing is 40' or more, the transmission resistance of ultrasonic waves becomes large, resulting in cracks forming on the cap, and insufficient adhesion between the packing and polyurethane due to creep of the polyurethane after autoclave sterilization. .

This lack of adhesion means that the cap and housing do not have enough elastic recovery force to prevent creep, so after high-pressure steam sterilization, the packing, polyurethane, and storage groove cannot achieve surface adhesion. Since there is a single point of close contact or a minute gap, this becomes the back side where liquid leaks.

If the JIS-A hardness of urethane is 99° or more, it will not have adequate elasticity as a filler for fixing hollow fibers. In other words, it becomes difficult to perform a cutting process to obtain a mirror-like cut surface so that there is no problem even if blood flows through the hollow fiber fixed with polyurethane.

In addition, if the JIS-A hardness of urethane is 90' or less, the hardness will be softer than that of the packing as shown in Figure 2-(B), so the urethane will dent during sealing and creep by the amount of the dent. This is not preferable in use because it tends to generate.

Table 1 (Notes on Table 1) The sealability test was performed by sterilizing the body fluid treatment device in a predetermined manner at 121'C for 20 minutes in high-pressure steam, and then determining the presence or absence of fluid leakage from the outside of the brat port.

■・・・No liquid leakage 0/100）O...
...Almost no liquid leakage 0 to 1/100)Δ...
...There is some liquid leakage (2 to 3/100) ×...
・Liquid leakage (5~to, '1oo) --- Unable to assemble due to ultrasonic transmission resistance hole (effects of the invention) As described above, in the present invention, polyurethane having appropriate hardness ( JIS-A hardness is 90' to 99°) and packing (JIS-A hardness is 25° to 40, selected as appropriate,
When used in combination, it is possible to maintain liquid tightness from the time of assembling the cap and housing to after high-pressure steam sterilization, which prevents liquid leakage due to creep formation and the contamination of bacteria from liquid leakage points. It is possible to provide a body fluid treatment device that is worry-free and hygienically safe to use.

[Brief explanation of drawings]

FIG. 1 shows a cap 2 and a housing 3 of a body fluid treatment device 1.
The assembly state diagram is shown. FIG. 2 is a partially enlarged view showing changes in the state of polyurethane and packing from the time of assembly of the body fluid treatment device of the present invention to after high-pressure steam sterilization. FIG. 3 is a partially enlarged view showing changes in the state of polyurethane and packing from the time of assembly of a conventional body fluid treatment device to after high-pressure steam sterilization. In the figure, 1 is a body fluid treatment device, 2 is a cap, 3 is a housing, 4 is a hollow fiber, 5 is polyurethane, 6 is a body fluid outlet, 7 is a gasket fitting groove, and 8 is a gasket. Patent applicant Kawasumi Chemical Industry Co., Ltd. Tsubo + 2EJ (A) (B) Pain 3 times (・ha) (B) (C1

Claims (1)

[Claims] (1) Body fluids that are assembled by being brought into fluid-tight contact with polyurethane that fixes the packing installed between the cap having a flow port for body fluids and the housing housing the hollow fibers, and the ends of the hollow fibers housed in the housing. A body fluid treatment device characterized in that the packing has a JIS-A hardness of 25° to 40°, and the polyurethane has a JIS-A hardness of 90° to 99°.