Abstract: Provided are a polyol composition in which hard caking does not occur when stored for a long period of time, and a polyurethane foam using the same. The polyol composition comprises a polyol compound, a foaming agent, a filler, and a metal oxide fine particle, the foaming agent including a hydrofluoroolefin, and the metal oxide fine particle having a count number ratio of OH ions of a metal constituting the metal oxide fine particle with respect to a total count number of all ions measured using time-of-flight secondary ion mass spectrometry of 0.1 or less.

Abstract: The polysulfone hollow fiber membrane of the invention has an inner dense skin layer composed of a polysulfone and a less amount of a polyvinylpyrrolidone, a content of the polyvinylpyrrolidone in the dense skin layer being higher than that in an outer surface layer. This membrane has excellent biocompatibility and antithrombogenetic ability and is, therefore, useful in body fluid treatment, such as hemodialysis, hemofiltration and hemoconcentration, without clogging with thrombi.

Abstract: A composite hollow fiber type separation membrane which has three layers comprising a selective separation layer, an ultra-microporous layer and a porous layer, said selective separation layer, said ultra-microporous layer, said porous layer being arranged in said order commencing from the inner surface of said hollow fiber membrane;wherein said selective separation layer is formed on said ultra-microporous layer without penetrating into said ultra-microporous layer and has a non-porous, dense structure, the average thickness of said layer being 0.01-2.mu., and the coefficient of variation in thickness thereof being less than or equal to 25%;wherein said ultra-microporous layer has a surface in which the presence of pores cannot be confirmed by 24,000x scanning electron microscopy, but which has fluid permeability at least 10 times that of said selective separation layer, the thickness of said layer being less than or equal to 0.08.mu.

Abstract: The polysulfone hollow fiber membrane provided by the present invention can prohibit bacteria, bacilli, viruses and the like, and is therefore useful, besides as an industrial filter for water purification, as a membrane for body fluid filtration or condensation. In particular, the polysulfone hollow fiber membrane is, being excellent in removing .beta..sub.2 -MG, markedly useful as a membrane for treating body fluid such as hemodialysis and hemofiltration.

Abstract: A composite hollow fiber type separation membrane which has three layers comprising a selective separation layer, an ultra-microporous layer and a porous layer, said selective separation layer, said ultra-microporous layer, said porous layer being arranged in said order commencing from the inner surface of said hollow fiber membrane;wherein said selective separation layer is formed on said ultra-microporous layer without penetrating into said ultra-microporous layer and has a non-porous, dense structure, the average thickness of said layer being 0.01-2.mu., and the coefficient of variation in thickness thereof being less than or equal to 25%;wherein said ultra-microporous layer has a surface in which the presence of pores cannot be confirmed by 24,000 .times. scanning electron microscopy, but which has a fluid permeability at least 10 times that of said selective separation layer, the thickness of said layer being less than or equal to 0.08.mu.

Abstract: A filtration apparatus for removing undesirable components from a solution to be treated, comprises a module in which a number of hollow fibers are fixed at one end thereof by cast-molding materials, and is opened at the end portion above described and closed at another end portion thereof, in which said solution to be treated can be kept from leaking out of a mechanically sealed portion. Any defect in the sealed portion can be detected from the outside by the provision of an opening which leads the leaked solution to the outside of the apparatus, instead of allowing it to combine with the filtrate. The apparatus is preferably used for the manufacture of purified water which is free from bacteria, pyrogene, and the like. Ultra-purified water of remarkably high purity can be obtained when the apparatus is used as a check filter in a process for manufacturing ultra-purified water.

Abstract: A bulk polymerization reactor takes the form of a vertical, cylindrical vat of a jacket construction defining a reaction chamber which a rotary drive shaft having an off-center longitudinal section with perforated discs and shearing blades extends vertically through. Successful preclusion of abnormal stagnation of the liquid phase in the reaction chamber during polymerization avoids undesirable coloring in the product while assuring stable polymerization and high yield.

Abstract: A polyvinyl alcohol (PVA) microporous membrane is disclosed which is prepared by a process which comprises forming a PVA membrane containing fine silica particles therein and substantially extracting said silica particles from said membrane, thereby forming a plurality of micropores therein with an average diameter of 0.01 to 50 microns and a porosity of at least 60%.

Abstract: A method is provided for continuously manufacturing high impact strength thermoplastic resins comprised of the sequential steps of (a) bulk-polymerizing a monomer solution, which contains a diene type rubber polymer or a graft polymer obtained by extracting the rubber polymer particle or vinyl monomer grafted polymer particle in latex with vinyl monomers which contain 5-20 percent by weight of water at a temperature of 85.degree.-135.degree.C, while continuously stirring the solution, vaporizing the volatile components, condensing the volatile component and recycling them back to reaction mixture, until the solid content in the reaction mixture reaches 40-75 percent by weight, and thereafter (b) bulk polymerizing the resulting prepolymer solution under the condition that plug-flowing can be attained with a temperature gradient 100.degree.-170.degree.C at the top of the reaction vessel and 170.degree.-270.degree.

Abstract: Symmetrical and unsymmetrical ketones are produced from aldehydes (aliphatic, alicyclic or aromatic aldehydes) or their mixtures according to the process of the present invention which comprises contacting the aldehydes or mixtures theirof with a catalyst selected from the group consisting of zirconium oxide and combinations of zirconium oxide with an alkali metal oxide and/or an alkaline earth metal oxide. Said catalyst is used with or without a carrier. The process is operated in the vapor phase at elevated temperature in the presence or absence of steam.

Abstract: High impact resistant thermoplastic resins are produced in three steps: (a) graft polymerizing a minor amount of unsaturated monomer onto a major amount of diene type rubber polymer in latex form, (b) mixing the grafted diene type rubber latex with a monomer or monomers, extracting the grafted rubber polymer particles into the monomer phase and separating and discarding the water phase to obtain a grafted rubber polymer particle dispersed monomer solution, and (c) bulk polymerizing the resulting rubber polymer particle dispersed monomer solution.

Abstract: Ketones are prepared with a high yield and a prolonged catalyst life, by reacting an aldehyde selected from the group consisting of straight chain or branched chain aliphatic aldehydes having a carbon number of 4-10 (inclusive) and aromatic aldehydes represented by the general formula of ##SPC1##Wherein n is 0-5 with a monocarboxylic acid selected from the group consisting of acetic acid and propionic acid, at a temperature of 200.degree.-600.degree.C, in the presence of a catalyst of zirconium oxide alone or a mixture of zirconium oxide and at least one kind of the metal oxide selected from the group consisting of alkali metal oxides and alkaline earth metal oxides.