Method of treating a cellulosic hollow fiber
Abstract
Abstract Method of treating a cellulosic hollow fiber which is being particularly adapted for use in hemodialysis or a similar extracorporeal treatment of blood. According to the described method the hollow fiber, possibly after rinsing with an alcoholic solution or fluorinated hydrocarbons, is exposed to swelling with use of an aqueous solution prior to drying and/sterilization of the hollow fiber. Examples of aqueous solutions can be water, water/glycerol, and water/glycerol/alcohol. Preferably said aqueous solution contains glycerol in an amount of 4-35%, such as 12-35%, preferably 16-35%. The aqueous solution can be applied to the inside and/or the outside of the hollow fiber so as to bring about a diffusive and/or a convective transport of water and/or glycerol into the hollow fiber wall. The rate of diffusion can be increased by increasing the temperature of the aqueous solution, by increasing the contact time between the aqueous solution and the hollow fiber, or by increasing the glycerol content of the aqueous solution, and the convective transport of said substances is achieved by applying the aqueous solution under pressure. After drying, the hollow fiber can be sterilized either by temperature or by radiation without any substantial loss of permeability characteristics.
Inventors
- 👤 Kurt Spranger
- 👤 Bernd A. W. Beck
Bibliographic Details
Claims Analysis
Total Claims: 13References Cited (Backward Citations)
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