Noriyuki Koyama has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
Abstract: A method of manufacturing a porous membrane by dissolving vinylidene fluoride polymer in a good solvent such as acetone and then causing solidification of the resultant solution in a non-solvent. The dissolution of the vinylidene fluoride polymer in the solvent is done in a predetermined pressure condition, namely 0.1 kg/cm.sup.2, preferably in a range of 0.5 to 5.0 kg/cm.sup.2.
Abstract: A hydrophilic porous membrane of polyvinylidene fluoride excelling in perviousness to water and other various properties and enjoying high commercial value, having uniform hydropilicity imparted to the surface of pores therein, which porous membrane is characterized by the fact that the reflection spectrum thereof in the visible zone is substantially unchanged from that which existed before the treatment for impartation of hydrophilicity. A method for the production of the hydrophilic porous membrane, characterized by chemically treating the porous membrane in a strong alkali solution containing an oxidizing agent.
Abstract: A hydrophilic porous membrane comprises a porous membrane made of a hydrophobic polymer and a coating formed on at least one surface of the porous membrane and on the inner surface of pores of the membrane with a water-insoluble hydrophilic polymer soluble in a solvent exhibiting satisfactory stability and a satisfactory wetting property with respect to the hydrophobic polymer and a method for the manufacture of the hydrophilic porous membrane.
Abstract: In a method for the manufacture of a porous membrane by the steps of causing a polymer solution to flow and spread in a uniform thickness on a substrate and solidifying the formed layer of the polymer solution in a bad solvent, the improvement which comprises using a fluorinated hydrocarbon as the bad solvent and optionally carrying out the removal of a good solvent mingling into the fluorinated hydrocarbon during the course of the solidification by the technique of extraction from water, and repeating the fluorinated hydrocarbon.