Abstract: Disclosed are heat-resisting porous membranes or hydrophilized heat-resisting porous membranes comprising a polyolefin, especially a polyethylene or a polypropylene membrane having a crosslinked polymer held thereon, the crosslinked polymer being composed principally of (a) a polymerizable monomer containing one acid anhydride group or two esterified carboxyl groups or a monomer having at least one carboxylic group and (b) divinylbenzene, or of (a), (b) and further (c) styrene or a derivative thereof, or of (b) and (c). These membranes are prepared by thermally polymerizing some of monomer components from (a) through (c) held on at least a part of the surface of the porous membranes and optionally by further hydrophilizing the crosslinked polymer. The resulting porous membranes are useful for membrane separation requiring steam sterilization and for membrane separation of water of a high temperature.

Abstract: Disclosed is a porous membrane consisting of a film-forming polymer characterized in that:(a) in at least one surface thereof, pores extending in a direction substantially perpendicular to the membrane surface are present at a surface pore density of 20 to 80%, said pores having an average pore diameter within the range of 0.01 to 100 .mu.m, a ratio of major to minor axis within the range of 1.0 to 2.0, and a coefficient of variation of pore diameter within the range of 0 to 50%; and(b) the overall porosity of said porous membrane is within the range of 20 to 90%.

Abstract: The present invention discloses a hydrophilized porous membrane with a crosslinked hydrophilic polymer, which is composed principally of diacetone acrylamide, held physically on at least a part of the pore walls of a starting porous polyolefin membrane, as well as its production process. This hydrophilized porous polyolefin membrane has long-lasting hydrophilicity and good mechanical strength. Its components are dissolved out only minimally in application.

Abstract: Porous membranes are produced by dissolving a film-forming polymer in a good solvent for the polymer, forming a film of the resulting polymer solution, and forcibly contacting saturated steam or mist-containing steam with at least one surface of said film. Such porous membranes have pores having a narrow pore diameter distribution and extending in a direction substantially perpendicular to the membrane surface at a high surface pore density on at least one surface thereof.

Abstract: Disclosed are a multilayer composite hollow fiber comprising at least one nonporous separating membrane layer (A) performing a separating function and two or more porous layers (B) performing a reinforcing function, the layer (A) and the layers (B) being alternately laminated so as to give a structure having internal and external surfaces formed by the porous layers (B), as well as a method of making such a hollow fiber.In this multilayer composite hollow fiber, the separating membrane can be formed as an ultrathin, homogeneous membrane. Moreover, the separating membrane is not liable to get damaged owing to the unique structure of the hollow fiber. Furthermore, such hollow fibers can be readily and stably produced on an industrial scale.

Abstract: The present invention discloses a hydrophilized porous polyolefin membrane with a polymer of a monomer, which has an HLB value of 2-20, held on at least a part of the pore walls of a porous polyolefin membrane as well as its production process. This hydrophilized porous polyolefin membrane has long-lasting hydrophilicity and good mechanical strength.

Abstract: Disclosed are a multilayer composite hollow fiber comprising at least one nonporous separating membrane layer (A) performing a separating function and two or more porous layers (B) performing a reinforcing function, the layer (A) and the layers (B) being alternately laminated so as to give a structure having internal and external surfaces formed by the porous layers (B), as well as a method of making such a hollow fiber.In this multilayer composite hollow fiber, the separating membrane can be formed as an ultrathin, homogeneous membrane. Moreover, the separating membrane is not liable to get damaged owing to the unique structure of the hollow fiber. Furthermore, such hollow fibers can be readily and stably produced on an industrial scale.

Abstract: The present invention discloses a hydrophilized porous membrane with a crosslinked hydrophilic polymer, which is composed principally of diacetone acrylamide, held physically on at least a part of the pore walls of a starting porous polyolefin membrane, as well as its production process. This hydrophilized porous polyolefin membrane has long-lasting hydrophilicity and good mechanical strength. Its components are dissolved out only minimally in application.

Abstract: The present invention discloses a hydrophilized porous polyolefin membrane with a polymer of a monomer, which has an HLB value of 2-20, held on at least a part of the pore walls of a porous polyolefin membrane as well as its production process. This hydrophilized porous polyolefin membrane has long-lasting hydrophilicity and good mechanical strength.

Abstract: A wiper control device for a vehicle capable of accurately stopping wiper blades always at the lowermost position of a wiping range regardless of the rotating speed of a wiper motor. The wiper control device automatically stops the wiper motor at the lowermost position of the wiper blades with a control circuit which obtains a sliding angle corresponding to the rotating speed of the wiper motor from the rotating speed of the motor and controls to flow an electric current continuously in the motor during the time while the motor reaches a rotating position even after the motor is interrupted by selecting the cam contact position with respect to the annular electrode. Thus, this wiper control device can eliminate to disturb the visual field of a driver with the wiper blades.

Abstract: An azimuth determinating apparatus wherein the azimuth sensor is oriented to a specified direction, and the deviation of the two-component detection signals of the azimuth sensor from the pointing direction of the azimuth sensor are corrected by the adjustment of the two-component detection signals with the adjusting circuit in accordance with the indication on the amount of deviation indicated by the indicating circuit, whereby distortion of the output signals due to the residual magnetism of the azimuth sensor is corrected and the true azimuth can be determined.