Porous membrane
AssigneeAsahi Kasei Medical Co., Ltd.
InventorsYasutaka Takazono, Masayasu Komuro
Life of this patent
Estimating the term…
Abstract
The problem is to provide a porous membrane with a reduced phenomenon in which membranes firmly adhere to one another during production of the porous membrane (membrane adhesion). The problem is solved by a porous membrane comprising a hydrophobic polymer and a hydrophilic polymer, wherein an average value T of ratios of the number of counts of ions derived from the hydrophilic polymer to the number of counts of ions derived from the hydrophobic polymer is 1.0 or more when a surface of the porous membrane is measured by time-of-flight secondary ion mass spectrometry (TOF-SIMS).
Claims2
A method for producing a porous membrane that includes a hydrophobic polymer and a hydrophilic polymer, or for reducing membrane adhesion after hydrophilizing, the method comprising:
- a hydrophilization process of hydrophilizing a base material membrane comprising a hydrophobic polymer by coating the base material membrane with a hydrophilic polymer to obtain a hydrophilized porous membrane, wherein the hydrophilic polymer is a methacrylate-based polymer;
- and
- an adjustment process of treating the hydrophilized porous membrane so that an average value T of ratios of the number of counts of ions derived from the hydrophilic polymer to the number of counts of ions derived from the hydrophobic polymer is 1.0 or more based on a time-of-flight secondary ion mass spectrometry (TOF-SIMS) measurement of a surface of the porous membrane, wherein
- the ions derived from the hydrophilic polymer are C4H5O2 (m/z=85) ions, and wherein
- the adjustment process comprises subjecting the hydrophilized porous membrane to high-pressure hot-water treatment in a state where the membrane is completely immersed in hot water and the temperature of the hot water is 120° C. or higher.
Dependencies are inferred from the claim text.