Abstract: A composite structure comprising two polytetrafluoroethylene porous layers and a framework structural member having a plurality of gaps or openings, the framework structural member being disposed between the two polytetrafluoroethylene porous layers, wherein the composite structure is structured such that the polytetrafluoroethylene porous layers are united together by being adhered with each other through the gaps or openings of the framework structural member and such that the respective polytetrafluoroethylene porous layers (A1) and (A2) are united with the framework structural member closely along the surfaces of the respective constituent elements of the framework structural member in such a manner as to wrap the respective elements. The method of manufacturing the composite structure is characterized in that it includes a step of applying pressure through a mass of fine particles.

Abstract: An expanded porous polytetrafluoroethylene film having residual strain of at most 11.0% as measured after a load required to indent a rod, which is in a columnar form that its outer diameter is at least 2 mm and at least 1.9 times as much as the thickness of the film, and has a smooth plane perpendicular to its axis at a free end surface thereof and a modulus of longitudinal elasticity of at least 1.0×104 kgf/mm2, up to 20% of the film thickness at a strain rate of 100%/min from the free end surface is applied repeatedly 20 times, and a production process of the porous film, in which a step of compressing an expanded porous polytetrafluoroethylene film having a high draw ratio is provided.

Abstract: A processing method of forming a through-hole in a workpiece by means of a pulsed laser beam includes the steps of providing a removable sacrifice layer on the workpiece, forming a through-hole in the workpiece by the laser beam in a state where the sacrifice layer is provided, and removing the sacrifice layer from the workpiece after the step of forming the through-hole.

Abstract: In order to easily control the laser pulse width and perform high-precision processing, the method for processing a material by laser ablation according to the present invention is characterized in that the material having a region of which a double logarithmic chart shows a linearly-shaped line with a gradient of not more than 0.5, when a relationship between laser pulse width and ablation threshold is represented in the logarithmic chart with a laser pulse width in picosecond plotted along the horizontal axis and an ablation threshold in J/cm2 plotted along the vertical axis, is processed by the pulsed laser beam having the laser pulse width within the region.

Abstract: Provided is an anisotropic conductive sheet (8) having heat resistance and cold resistance and suitable for connection of electrodes. The anisotropic conductive sheet of the present invention has conductivity in the thickness direction, wherein the base film (1), which is a film made of synthetic resin having an electrical insulation property, has a plurality of holes (3) formed in the thickness direction, and the holes (3) are open to one main surface of the base film and closed to the other main surface, wherein a metal is adhered to the closed parts (2a) and the inner walls (2b) of the holes (3) so that by contacting electrodes (7) with the closed parts (2a) respectively from the outside, the electrodes (7) can electrically be connected through the adhered metal to the main surface where the holes (3) are open.

Abstract: In a composite porous resin base material, a porous resin film is provided with a functional section whereupon an electrode and/or a circuit is formed. On the periphery surrounding the functional section, a step having a height different from that of the functional section is formed, and a frame plate is arranged on a plane of the step. Provided is the composite porous resin base material which has a structure wherein the frame plate having rigidity is attached to the porous resin base material whereupon the electrode and/or a circuit is formed without deteriorating characteristics such as elasticity and conductivity of the porous resin base material.

Abstract: A microhole-formed stretched porous polytetrafluoroethylene material, in which a microhole having a hole diameter greater than an average pore diameter of a stretched porous polytetrafluoroethylene material is formed in the stretched porous polytetrafluoroethylene material by irradiation of a pulse laser beam having a pulse length of at most 10 picoseconds, and the microporous structure of the wall surface of the microhole is substantially retained without being destroyed, a production process thereof, and an abrasion working process.

Abstract: A method of manufacturing a perforated porous resin substrate, the method including the following steps: Step 1 of forming at least one perforation penetrating in the thickness direction from a first surface to a second surface in a porous resin substrate made of a resin material containing a fluoropolymer; Step 2 of etching treatment conducted by putting an etchant containing an alkali metal in contact with the wall face of each perforation; and Step 3 of putting an oxidizable compound or a solution thereof in contact with a degenerative layer generated by the etching treatment, and thereby removing the degenerative layer. A method of manufacturing a porous resin substrate in which electrical conductivity is afforded to the wall face of the perforation.

Abstract: A composite structure comprising two polytetrafluoroethylene porous layers and a framework structural member having a plurality of gaps or openings, the framework structural member being disposed between the two polytetrafluoroethylene porous layers, wherein the composite structure is structured such that the polytetrafluoroethylene porous layers are united together by being adhered with each other through the gaps or openings of the framework structural member and such that the respective polytetrafluoroethylene porous layers (A1) and (A2) are united with the framework structural member closely along the surfaces of the respective constituent elements of the framework structural member in such a manner as to wrap the respective elements. The method of manufacturing the composite structure is characterized in that it includes a step of applying pressure through a mass of fine particles.

Abstract: The object of the invention is to provide an anisotropic conductive sheet which obtains good conductivity without damaging a wafer of a semiconductor nor electrode terminals of a conduction measurement instrument due to loading during inspection of the wafer. An anisotropic conductive sheet 1 of the invention is formed such that a porous resin layer is formed on inner walls of a plurality of through holes perforated in the thickness direction of an electrically insulating porous sheet 2, and the surfaces of skeletons of the porous resin are coated with metal. Examples of the porous resin layer include those which are obtained by means of foaming a fluororubber or a tetrafluoroethylene-propylene copolymer rubber, having an open-cell structure, and cross-liking the same through irradiation with electron beams. The sheet is particularly favorable for a porous resin.

Abstract: An object of the present invention is to provide a method for manufacturing a porous material in which complicated and fine through portions, recessed portions, and the like have been patterned. It is to provide a patterned porous molded product or nonwoven fabric, in which a plated layer has been selectively formed on the surfaces of the through portions and the recessed portions. With the invention, a mask having through portions in a pattern is placed on at least one side of the porous molded product or the nonwoven fabric. A fluid or a fluid containing abrasive grains is sprayed from above the mask, thereby to form through portions or recessed portions, or both of them, to which the opening shape of each through portion of the mask has been transferred, in the porous molded product or the nonwoven fabric.

Abstract: An expanded porous polytetrafluoroethylene film having residual strain of at most 11.0% as measured after a load required to indent a rod, which is in a columnar form that its outer diameter is at least 2 mm and at least 1.9 times as much as the thickness of the film, and has a smooth plane perpendicular to its axis at a free end surface thereof and a modulus of longitudinal elasticity of at least 1.0×104 kgf/mm2, up to 20% of the film thickness at a strain rate of 100%/min from the free end surface is applied repeatedly 20 times, and a production process of the porous film, in which a step of compressing an expanded porous polytetrafluoroethylene film having a high draw ratio is provided.

Abstract: An expanded polytetrafluoroethylene formed article in which a synthetic resin having a tensile elastic modulus higher than the tensile elastic modulus of polytetrafluoroethylene is applied on or impregnated into at least a part of a porous expanded polytetrafluoroethylene rod-shaped article, and the diameter of the part to which the synthetic resin has been applied or impregnated is reduced by applying twist deformation. A composite article including the expanded polytetrafluoroethylene formed article, as well as a method of producing the formed article, is also provided.

Abstract: The present invention is directed to an anisotropic conductive film and manufacturing methods thereof, in which an electrically insulative porous film made of synthetic resin is used as a base film and in which conductive parts capable of being provided with conductiveness in the film thickness direction are formed independently at plural positions of the base film by adhering conductive metal to resinous parts of porous structure in such a manner as piercing through from a first surface to a second surface.

Abstract: A production process of a perforated porous resin base, comprising Step 1 of impregnating the porous structure of a porous resin base with a liquid or solution; Step 2 of forming a solid substance from the liquid or solution impregnated; Step 3 of forming a plurality of perforations extending through from the first surface of the porous resin base having the solid substance within the porous structure to the second surface in the porous resin base; and Step 4 of melting or dissolving the solid substance to remove it from the interior of the porous structure, and a production process of a porous resin base with the inner wall surfaces of the perforations made conductive, comprising the step of selectively applying a catalyst only to the inner wall surfaces of the perforations to apply a conductive metal to the inner wall surfaces.

Abstract: Disclosed are expanded polytetrafluoroethylene products, such as porous polytetrafluoroethylene tubes, having high axial tear strength and a process for their production. Each expanded polytetrafluoroethylene product has a microstructure, which comprises fibrils and nodes interconnected with each other by the fibrils, and has an axial tear strength of not lower than 6,000 gf/mm as calculated in accordance with the following formula: L/[T×(V/100)] where L (gf) is an axial tear load, T (mm) is a wall thickness, and V (%) is a volume ratio of resin. The process for the production of the expanded polytetrafluoroethylene product includes a high-speed extrusion step.

Abstract: A prosthesis for a blood vessel, which is an expanded porous polytetrafluoroethylene tube having a fine fibrous structure with nodes connected to each other by fibrils. The average fibril length is at least 40 &mgr;m, and the tube has a porosity of at least 70%. The load required for compressing the tube by 10% in its axial direction at a strain rate of 100%/min is at least 10 gf. The resistant force per unit sectional area of the tube produced upon the 10% compression is at least 1.0 gf/mm2.

Abstract: An artificial blood vessel formed into a tube from expanded polytetrafluoroethylene (PTFE), wherein the tube is composed of nodes connected by fibrils creating pores within the wall of the tube. The inner surface of the tube and surfaces of pores comprise a layer extending radially from the inner surface, toward the outer surface of the tube to a depth of 5% to 96%, are chemically treated to make the tube inner surface and pores hydrophilic. Tissue-inducing substances and anti-thrombotic substances are then covalently bonded to the hydrophilic inner surface of the tube and pores. An artificial blood vessel of the invention exhibits a good patency ratio for a long period of time.

Abstract: A magnetic recording/reproducing apparatus being able to use a normal-sized cassette and a small sized cassette according to a user's selection. The apparatus comprises a supply reel stand for engaging with a supply reel; a supply reel stand base for supporting the supply reel stand; a take-up reel stand for engaging with a take-up reel; a take-up reel stand base for supporting the take-up reel stand; a reel stand displacing mechanism for displacing the supply reel stand base and the take-up reel stand base according to a size of the normal-sized cassette and a size of the small sized cassette. The reel stand displacing mechanism displaces the supply reel stand base and the take-up reel stand base by using a drive force transmitted from the tape loading mechanism.

Abstract: A magnetic recording and reproducing device comprises a tape guide mechanism for taking up the tape within the cassette when unloaded state, and withdrawing the tape from the cassette so as to wind the tape on the rotary head drum when loaded state. The mechanism comprises a first guide slot, a first moving member, and a first guide roller provided on the first moving member. The center line of the tape wound on the first guide roller lies in the reference plane. The mechanism comprises a second guide slot provided on take-up reel side and having a slanting part, a second moving member, and a second guide roller provided on the second moving member. The second guide roller rotates about a second axis having a predetermined tilt angle and a predetermined direction angle so that the center line of the tape is situated lower than the reference plane, is wound from the rotary head drum so that the center line of the tape is oriented toward the reference plane.