Abstract: Provided is a porous polytetrafluoroethylene (PTFE) membrane that satisfies the following expressions: 0.2?F?4.0; 0.2?R?1.0; and R??0.1F+0.5, for the Frazier number F [cm3/sec/cm2] and the water entry pressure R [MPa]. This porous PTFE membrane may be a single-layer membrane. This porous PTFE membrane has the properties suitable for use as a waterproof air-permeable membrane, and achieves a good balance between high water resistance and high air permeability.

Abstract: Provided is a method including: a step A of extruding a mixture containing a fine PTFE powder and a liquid lubricant into a sheet form so as to obtain a PTFE sheet; a step B of rolling the PTFE sheet by passing the sheet between a pair of rolls in the longitudinal direction of the sheet; a step C of heating the rolled PTFE sheet to a temperature of 19° C. or higher; a step D of stretching the rolled PTFE sheet having a temperature of 19° C. or higher in the width direction of the sheet; a step E of removing the liquid lubricant from the PTFE sheet; and a step F of stretching the PTFE sheet, from which the liquid lubricant has been removed, in both the longitudinal direction and the width direction so as to form pores in the sheet.

Abstract: Provided is a porous polytetrafluoroethylene (PTFE) membrane that satisfies the following expressions: 0.2?F?4.0; 0.2?R?1.0; and R??0.1F+0.5, for the Frazier number F [cm3/sec/cm2] and the water entry pressure R [MPa]. This porous PTFE membrane may be a single-layer membrane. This porous PTFE membrane has the properties suitable for use as a waterproof air-permeable membrane, and achieves a good balance between high water resistance and high air permeability.

Abstract: Provided is a method including: a step A of extruding a mixture containing a polytetrafluoroethylene (PTFE) fine powder having a standard specific gravity (SSG) of 2.19 or less and a liquid lubricant into a sheet using a flat die so as to obtain a PTFE sheet; a step B of rolling the PTFE sheet by passing the sheet between a pair of rolls in a longitudinal direction of the sheet; a step C of stretching the rolled PTFE sheet in a transverse direction of the sheet; a step D of removing the liquid lubricant from the PTFE sheet; and a step E of stretching the PTFE sheet, from which the liquid lubricant has been removed, both in the longitudinal direction of the sheet and in the transverse direction of the sheet, for example, at an area stretch ratio of 150 to 700, so as to make the sheet porous. According to this production method, it is possible to increase the PF value of the porous PTFE membrane.

Abstract: The present invention provides an elastomer composition comprising a mixture of (A) a perfluoroelastomer and (B) at least one elastomer selected from fluorine rubbers, silicone rubbers and ethylene-propylene based rubbers, in a mixing ratio (A/B) of from 0.5/99.5 to 80/20 in terms of weight ratio.

Abstract: The present invention provides an elastomer composition comprising a mixture of (A) a perfluoroelastomer and (B) at least one elastomer selected from fluorine rubbers, silicone rubbers and ethylene-propylene based rubbers, in a mixing ratio (A/B) of from 0.5/99.5 to 80/20 in terms of weight ratio.

Abstract: In a tactile-feedback rotary electrical component, a first U-shaped spring is mounted in a recessed holding portion formed in a housing along the axial direction of an operating member. When the operating member is rotated, a protuberance formed on the first U-shaped spring engages with and disengages from recesses formed in the operating member, thereby producing tactile feedback.

Abstract: In a multidirectional input device, a surface of a bottom plate facing the bottom of an operating member is provided with a projection having a taper portion that gradually rises from the outer periphery toward the center, wherein the operating member is tilted with the tilting operation of a control shaft and contacts the projection to regulate the motion of the operating member. Therefore, the operating member does not slip, and a tactile feel is not produced in the tilting operation.

Abstract: A rotating electrical component, in which, on mating surface sides of the flange of the support member and the flange of the operating shaft, on both sides of the center of rotation on the line which passes through the center of rotation of the operating shaft, there are provided projections and recesses which differ in diameter measured from the center of rotation of the operating shaft and can be engaged and disengaged in positions where they will not overlap each other in the circumferential direction.