Abstract: Provided is a novel manufacturing method for a conical hollow needle that makes it possible to efficiently form a conical part that has a nearly perfectly circular outer circumferential surface shape. The present invention is a method of manufacturing a conical hollow needle that has a conical part that has a tapered outer circumferential surface. The manufacturing method involves immersing a hollow needle having a straight shape in an electrolyte solution to conically electropolish an outer circumferential surface. From a start to an end of the electropolishing, the hollow needle, which serves as an anode, is sandwiched between a pair of cathodes at a prescribed distance therefrom in a radial direction, and the hollow needle is rotated around a needle axis thereof to change which faces of the hollow needle are opposite to the cathodes.

Abstract: A puncture needle includes a needle tube 1 provided with a spiral groove 3 and wall surfaces 3a and 3b of the spiral groove 3 serve as a surface for reflecting ultrasonic waves. The spiral groove is formed on the peripheral surface of the needle tube such that a grinding stone 2 is brought into contact with the peripheral surface of the needle tube while the needle tube 1 is being moved in its axial direction and rotated. The wall surfaces of the spiral groove formed on the needle tube serve as a reflection surface to change the orientation of the reflection surface in the axial direction of the needle tube according to change in position of the spiral. Therefore, even if a direction in which an ultrasonic wave is applied to the puncture needle is fixed, any portion of the reflection surface changing in orientation can become a surface for reflecting well ultrasonic waves, so that good ultrasonic waves can be obtained.

Abstract: An injection needle 1 made of an alloy containing cobalt and molybdenum is manufactured as follows. First, a lancet cut is carried out to a pipe-like metallic material composed of the alloy containing cobalt and molybdenum to form a blade tip 3 and a blade part 5. Then, a distal end part 1A including the blade tip 3 is mechanically polished, and thereafter, the distal end part 1A is immersed in an electrolytic solution and electrolytically polished. Thus, burrs at the blade tip 3 or the like generated during mechanical polishing are removed. Since the injection needle 1 is composed of the alloy containing cobalt and molybdenum, compared to a conventional injection needle made of stainless steel, an injection needle in which the surface roughness of an inner peripheral surface of the injection needle is low and smooth can be provided.

Abstract: A medical hollow needle structured in accordance with the present invention, wherein the puncture resistance of a blade surface over the entire length in the puncture direction can be made substantially equal, and the patient's pain during needle puncture can be relieved due to a reduction in the peak level of puncture pain with the duration of sensory awareness of the puncture pain shortened by the use of the blade surface in a novel shape employing, in combination with each other, first to fourth inclined surfaces having specific inclination directions. Accordingly, the present invention provides a medical hollow needle with a blade surface in a novel shape whereby the puncture pain can be further reduced compared to needles with a conventional structure, and to provide a preferred method of producing such a medical hollow needle.

Abstract: A puncture needle includes a needle tube 1 provided with a spiral groove 3 and wall surfaces 3a and 3b of the spiral groove 3 serve as a surface for reflecting ultrasonic waves. The spiral groove is formed on the peripheral surface of the needle tube such that a grinding stone 2 is brought into contact with the peripheral surface of the needle tube while the needle tube 1 is being moved in its axial direction and rotated. The wall surfaces of the spiral groove formed on the needle tube serve as a reflection surface to change the orientation of the reflection surface in the axial direction of the needle tube according to change in position of the spiral. Therefore, even if a direction in which an ultrasonic wave is applied to the puncture needle is fixed, any portion of the reflection surface changing in orientation can become a surface for reflecting well ultrasonic waves, so that good ultrasonic waves can be obtained.

Abstract: An injection needle 1 made of an alloy containing cobalt and molybdenum is manufactured as follows. First, lancet cut is carried out to a pipe-like metallic material composed of the alloy containing cobalt and molybdenum to form a blade tip 3 and a blade part 5. Then, a distal end part 1A including the blade tip 3 is mechanically polished, and thereafter, the distal end part 1A is immersed in an electrolytic solution and electrolytically polished. Thus, burrs at the blade tip 3 or the like generated during mechanical polishing are removed. Since the injection needle 1 is composed of the alloy containing cobalt and molybdenum, compared to a conventional injection needle made of stainless steel, an injection needle in which surface roughness of an inner peripheral surface of the injection needle is low and smooth can be provided.

Abstract: A medical hollow needle structured in accordance with the present invention, wherein the puncture resistance of a blade surface over the entire length in the puncture direction can be made substantially equal, and the patient's pain during needle puncture can be relieved due to a reduction in the peak level of puncture pain with the duration of sensory awareness of the puncture pain shortened by the use of the blade surface in a novel shape employing, in combination with each other, first to fourth inclined surfaces having specific inclination directions. Accordingly, the present invention provides a medical hollow needle with a blade surface in a novel shape whereby the puncture pain can be further reduced compared to needles with a conventional structure, and to provide a preferred method of producing such a medical hollow needle.