Abstract: A method of making a catheter includes: performing an extrusion molding process while changing extrusion speeds of materials that are extruded, so as to form a catheter that includes: a catheter body, and a flexible portion that is provided at a distal portion of the catheter body, forms a most distal portion of the catheter, and is more flexible than the catheter body.

Abstract: A catheter assembly includes: a catheter; and an inner needle inserted through the catheter. The catheter includes: a catheter body; and a flexible portion that is located at a distal portion of the catheter body and forms a most distal portion of the catheter. An elastic modulus of the catheter body is greater than an elastic modulus of the flexible portion. The catheter has a mixed region in which the catheter body and the flexible portion overlap each other in a radial direction.

Abstract: Provided is an indwelling catheter which is stiff when being inserted into a vessel such as a blood vessel, softens after indwelling in the vessel, and conforms to a shape in a direction in which the vessel runs. In the indwelling catheter, the maximum value of a catheter repulsive force in a dry state at 25° C. is 0.10 N or more; the maximum value of the catheter repulsive force when immersed in warm water at 37° C. is 0.01 to 0.25 N; a ratio of the maximum value of the catheter repulsive force in a dry state at 25° C. to the maximum value of the catheter repulsive force when immersed in warm water at 37° C. is in a range of 3.5:1 or more; and the maximum value of the catheter repulsive force when immersed in warm water at 37° C. is 0.027 N or less after 5 minutes from indwelling.

Abstract: A catheter assembly includes: a catheter; and an inner needle inserted through the catheter. The catheter includes: a catheter body; and a flexible portion that is located at a distal portion of the catheter body and forms a most distal portion of the catheter. An elastic modulus of the catheter body is greater than an elastic modulus of the flexible portion. The catheter has a mixed region in which the catheter body and the flexible portion overlap each other in a radial direction.

Abstract: A catheter assembly includes: a catheter; a catheter hub; an inner needle; a needle hub; and a deflection suppressing mechanism suppressing deflection of the inner needle. The deflection suppressing mechanism includes an upper deflection suppressing portion positioned on an upper side of the inner needle and a lower deflection suppressing portion positioned on a lower side of the inner needle. At least one of the upper deflection suppressing portion and the lower deflection suppressing portion is movable with respect to the needle hub.

Abstract: A catheter assembly includes a catheter and an inner needle inserted through the catheter. The catheter has a catheter body and a flexible portion that is provided at a distal portion of the catheter body, includes a most distal portion of the catheter, and is more flexible than the catheter body.

Abstract: A catheter includes: a first port; a second port; a first lumen communicating with the first port; a second lumen configured to selectively communicate with the first port and/or the second port; and a switching mechanism part selectively switchable between a first switching state in which the first port and the second lumen communicate with each other and a second switching state in which communication between the first port and the second lumen is blocked.

Abstract: A catheter assembly includes a catheter; a catheter hub fixed to a proximal end portion of the catheter; a hollow needle having a needle tip and disengageably located in the catheter; a needle hub fixed to a proximal end portion of the needle; a guide wire slidably located in the needle, the guide wire being longer than the catheter and having a distal end that is protrudable from the needle tip; a guide wire hub configured to support the guide wire and move the guide wire with respect to the needle in association with movement of the guide wire hub; and a movement mechanism configured to retract the guide wire hub with respect to the needle hub such that the distal end of the guide wire is housed in the needle in association with forward movement of the catheter hub with respect to the needle hub.

Abstract: Provided is an indwelling catheter which is stiff when being inserted into a vessel such as a blood vessel, softens after indwelling in the vessel, and conforms to a shape in a direction in which the vessel runs. In the indwelling catheter, the maximum value of a catheter repulsive force in a dry state at 25° C. is 0.10 N or more; the maximum value of the catheter repulsive force when immersed in warm water at 37° C. is 0.01 to 0.25 N; a ratio of the maximum value of the catheter repulsive force in a dry state at 25° C. to the maximum value of the catheter repulsive force when immersed in warm water at 37° C. is in a range of 3.5:1 or more; and the maximum value of the catheter repulsive force when immersed in warm water at 37° C. is 0.027 N or less after 5 minutes from indwelling.

Abstract: A catheter assembly includes: a catheter; a catheter hub; an inner needle; a needle hub; and a deflection suppressing mechanism suppressing deflection of the inner needle. The deflection suppressing mechanism includes an upper deflection suppressing portion positioned on an upper side of the inner needle and a lower deflection suppressing portion positioned on a lower side of the inner needle. At least one of the upper deflection suppressing portion and the lower deflection suppressing portion is movable with respect to the needle hub.

Abstract: A catheter assembly includes a catheter and an inner needle inserted through the catheter. The catheter has a catheter body and a flexible portion that is provided at a distal portion of the catheter body, includes a most distal portion of the catheter, and is more flexible than the catheter body.

Abstract: A catheter includes: a first port; a second port; a first lumen communicating with the first port; a second lumen configured to selectively communicate with the first port and/or the second port; and a switching mechanism part selectively switchable between a first switching state in which the first port and the second lumen communicate with each other and a second switching state in which communication between the first port and the second lumen is blocked.

Abstract: A catheter assembly includes a catheter; a catheter hub fixed to a proximal end portion of the catheter; a hollow needle having a needle tip and disengageably located in the catheter; a needle hub fixed to a proximal end portion of the needle; a guide wire slidably located in the needle, the guide wire being longer than the catheter and having a distal end that is protrudable from the needle tip; a guide wire hub configured to support the guide wire and move the guide wire with respect to the needle in association with movement of the guide wire hub; and a movement mechanism configured to retract the guide wire hub with respect to the needle hub such that the distal end of the guide wire is housed in the needle in association with forward movement of the catheter hub with respect to the needle hub.

Abstract: An aluminum nitride single-crystal multi-layered substrate comprising an aluminum nitride single-crystal layer formed by direct reduction nitridation on a single-crystal ?-alumina substrate such as a sapphire substrate and an edge-type dislocation layer having a thickness of 10 nm or less in the vicinity of the interface between the both crystals. Threading dislocation is rarely existent in the aluminum nitride single-crystal layer existent on the surface. It is useful as a semiconductor device substrate.

Abstract: A highly crystalline aluminum nitride multi-layered substrate comprising a single-crystal ?-alumina substrate, an aluminum oxynitride layer and a highly crystalline aluminum nitride film as the outermost layer which are formed in the mentioned order, wherein the aluminum oxynitride layer has a threading dislocation density of 6.3×107/cm2 or less and a crystal orientation expressed by the half-value width of its rocking curve of 4,320 arcsec or less; and a production process thereof.

Abstract: An aluminum nitride single-crystal multi-layered substrate comprising an aluminum nitride single-crystal layer formed by direct reduction nitridation on a single-crystal ?-alumina substrate such as a sapphire substrate and an edge-type dislocation layer having a thickness of 10 nm or less in the vicinity of the interface between the both crystals. Threading dislocation is rarely existent in the aluminum nitride single-crystal layer existent on the surface. It is useful as a semiconductor device substrate.

Abstract: A highly crystalline aluminum nitride multi-layered substrate comprising a single-crystal ?-alumina substrate, an aluminum oxynitride layer and a highly crystalline aluminum nitride film as the outermost layer which are formed in the mentioned order, wherein the aluminum oxynitride layer has a threading dislocation density of 6.3×107/cm2 or less and a crystal orientation expressed by the half-value width of its rocking curve of 4,320 arcsec or less; and a production process thereof.