JPH06285160A - Hollow fiber cleaning method - Google Patents

Abstract

PURPOSE:To prevent removal of hole diameter holding agent from a hollow fiber membrane wall by cleaning in manufacturing a dialyzer, and prevent deterioration of water permeability by supplying fluorine-based liquid having specified values of an ozone breaking coefficient and a boiling point to the inner part of hollow fiber for selectively cleaning and eliminating oily material inside the hollow fiber while leaving the hole diameter holding agent in the hollow fiber. CONSTITUTION:Hollow fibers are bundled to be installed in a case of plastic such as polystyrene resin, acrylic resin, and polycarbonate resin, both ends of the hollow fiber bundle are fixed with binding agent of polyurethane or the like, and bound parts are cut to open the end parts of the hollow fiber for manufacturing a blood dialyzer. Fluorine-based inactive liquid is then supplied into the inner part of the hollow fiber for selectively cleaning and eliminating oily material such as liquid paraffin, etc., attached to the inner part of the hollow fiber only, while leaving glycerine as hole diameter holding agent inside the hollow fiber without being dissolved. For the fluorine-based inactive liquid, that having a boiling point of 110 deg.C or less, including no hydrogen or chlorine, and having an ozone breaking coefficient of zero is used.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for cleaning hollow fibers used in hemodialyzers.

[0002]

2. Description of the Related Art Conventionally, cellulose, cellulose acetate,
When a solution or melt of cellulose triacetate, polyacrylonitrile, polymethylmethacrylate, etc. is extruded from an orifice, oily substances such as liquid paraffin and isopropyl myristate are simultaneously exhaled inside the hollow fiber, and the state is filled with the oily substance. The hollow fiber of is spun. The hollow fiber fibers spun in this manner are bundled and loaded into the case of a hemodialyzer made of plastic such as polystyrene resin, acrylic resin, and polycarbonate resin,
After fixing both ends of the hollow fiber bundle with an adhesive, the adhesive is cut to open the ends of the hollow fibers to manufacture a hemodialyzer.
Then, the oily substance adhering to the inside of the hollow fiber is treated with ethyl alcohol or fluorochlorohydrocarbon to wash and remove the oily substance. However, when treated with ethyl alcohol, glycerin, which is a pore size holding material present inside the hollow fibers, is also washed and removed, and the water permeability of the hollow fiber bundle after washing is significantly reduced. Even if the hollow fiber in such a state is treated with glycerin again, it does not return to the original state.
Also, when treating with ethyl alcohol. There is also a method of preliminarily adding several% of glycerin to ethyl alcohol for washing, but this method complicates the step of vapor-depositing ethyl alcohol after washing, and the efficiency of the hemodialyzer manufactured is also lowered. In addition, when treated with fluorohydrocarbons, the substance destroys the ozone layer and deteriorates the global environment. Depending on the type of fluorohydrocarbon chloride, hemodialysis consisting of plastics such as polystyrene resin, acrylic resin, polycarbonate resin, etc. The case of the vessel may be destroyed.

[0003]

DISCLOSURE OF THE INVENTION The present invention prevents the above-mentioned problems of the prior art, namely, the removal of glycerol, which is a pore-size-retaining agent, from the wall of a hollow fiber membrane by washing during the manufacture of a dialyzer
This is to prevent a decrease in water permeability due to washing.

[0004]

According to the present invention, a liquid paraffin containing a fluorine-based inert liquid having an ozone depletion coefficient of zero and a boiling point of 110 ° C. or less in a hollow fiber in the production of a hemodialyzer using a hollow fiber. The present invention relates to a method for cleaning a hollow fiber, characterized in that an oily substance such as isopropyl myristate is selectively washed and removed, and at the same time, glycerol, which is a pore size holding material, is left in the hollow fiber.

That is, according to the present invention, the hollow fiber fibers are bundled and loaded into a case made of plastic such as polystyrene resin, acrylic resin or polycarbonate resin, and the both ends of the hollow fiber fiber bundle are fixed with an adhesive such as polyurethane and then bonded. The part is cut and the end of the hollow fiber is opened to manufacture a hemodialyzer. Then, a fluorine-based inert liquid is poured into the hollow fiber to selectively wash and remove only oily substances such as liquid paraffin and isopropyl myristate adhering to the inside of the hollow fiber. It remains inside the hollow fiber without being dissolved in the detergent.

The fluorine-based inert liquid having a boiling point of 110 ° C. or less as used in the present invention is a fluorine-based compound represented by the general formula C _n F _{2n + 2} in which n is 5 to 8 and contains hydrogen and chlorine. It is a fluorine-based liquid with an ozone depletion potential of zero. Therefore, it does not damage the global environment, and since it is completely inert, it does not damage the plastic case such as polystyrene resin, acrylic resin, polycarbonate resin, etc., in which the hollow fiber fiber bundle is loaded, regardless of high temperature or low temperature. Furthermore, the surface tension is very low (12-18 dyne / cm, 25 ° C.), it can easily and evenly penetrate into the fine pores of the hollow fiber to efficiently wash and remove only the oily substance, and it is nonflammable, so there is a danger of explosion. It is non-toxic, odorless and can safely perform the hollow fiber washing process.
Also, drying can be performed relatively easily.

The present invention will be specifically described below with reference to examples.

EXAMPLE When a solution of cellulose acetate was extruded through an orifice,
At the same time, an oily substance such as liquid paraffin was discharged into the inside of the hollow fiber to spin the hollow fiber filled with the oily substance. The hollow fiber fibers spun in this manner are bundled and loaded into the cases of hemodialyzers made of three types of plastics, polystyrene resin, acrylic resin, and polycarbonate resin, and both ends of the hollow fibers are bonded with urethane adhesive. After fixed, it was cut and the end of the hollow fiber was opened to manufacture a hemodialyzer. Then, a fluorine-based inert liquid C ₆ F ₁₄ having a boiling point of 56 ° C. was caused to flow inside the hollow fiber. Then, the liquid paraffin existing inside the hollow fiber was selectively removed, but the glycerin contained inside the hollow fiber remained without being dissolved. afterwards,
When air at 60 ° C. was supplied for 5 minutes, residual C ₆ F ₁₄
Was less than 1 mg / m ² and the efficiency of the hemodialyzer produced was high.

Comparative Example 1 In the same washing method as in Example 1 above, ethyl alcohol was used for washing instead of the fluorine-based inert liquid, and the hemodialyzer obtained had a marked dialysis efficiency. Fell.

Comparative Example 2 When 1,1-dichloro-1-fluoroethane was used for cleaning by the same cleaning method as in the above Example, a case of a hemodialyzer made of polystyrene resin, acrylic resin, polycarbonate resin plastic was found. It became cloudy and finally cracked and could not be washed.

Comparative Example 3 Fluorine having a boiling point of 155 ° C. was used for cleaning by the same cleaning method as in the above-mentioned Example.
Elementary inert liquid C₉F ₂₀Was used at 60 ° C after washing
Air was supplied for 5 minutes, but residual C₉F₂₀Is 20
00 mg / m²And was not removed.

[0012]

EFFECTS OF THE INVENTION According to the present invention, there is no problem of environmental pollution and damage to the module, and it is possible to prevent deterioration of water permeability of the hollow fiber due to washing during manufacture of the hemodialyzer using the hollow fiber. A hollow fiber having excellent properties is provided.

Claims (1)

[Claims] 1. A liquid paraffin, isopropyl myristate, present in a hollow fiber by flowing a fluorine-based liquid having an ozone depletion potential of zero and a boiling point of 110 ° C. or less into the hollow fiber in the production of a hemodialyzer using the hollow fiber. A method for cleaning a hollow fiber, characterized in that an oily substance such as is selectively washed and removed, and a pore diameter retaining agent is left in the hollow fiber.