Impregnated regenerated cellulose membrane and its manufacturing method

摘要

A non-fibrous regenerated cellulose film is passed through an aqueous bath containing as anchoring-plasticizing agent a water-soluble amide or amine containing at least 6 alkyleneoxy groups, each containing not more than 4 carbon atoms, and at least one hydrophobic substituent of at least 6 carbon atoms, and the film is dried. The term "amides" includes ureas, thioureas, carbazides and semicarbazides and the term "amines" includes amidines, guanidines, oximes and ammonium quaternaries. The number of alkyleneoxy groups may exceed 20; ethyleneoxy groups are preferred. Hydrophobic substituents specified include aryl, alkyl, aralkyl and alkaryl groups containing more than 6 carbon atoms, or chloroalkyl, chloroaryl, and ester groups. Desirably, such hydrophobic groups should contain more than 12 carbon atoms. The molecular weight of the agent preferably exceeds 5,000. The film preferably contains 10-20% of its dry weight of the agent, corresponding to impregnation to saturation with a solution containing 5-10% by weight of the agent, and has a pH of 6-8. The aqueous bath may contain other conventional agents to impart supplementary plasticization and anchoring properties to the film. Preferred anchoring-plasticizing agents include the reaction products with between 10 and 100 mols of ethylene oxide of N-2-hydroxyethylrosinamide or stearoguanimine, and of dimethyl (octadecylamidopropyl) amine. Many others are specified. After treatment the film, desirably after drying at 160-250 DEG F., may be treated on at least one side with a hydrophobic topcoat material. Those specified include nitrocellulose, cellulose acetate, methyl cellulose, polyethylene, deacetylated chitin, rubber, chlorinated rubber, rubber hydrochloride, ethyl cellulose, polybutyl methacrylate, moistureresistant lacquers, montan wax, carnauba wax and beeswax. U.S.A. Specifications 2,394,009, 2,757,102 and 2,764,507 are referred to.