Tanaka Kikinzoku Kogyo K.k.

Tokushima University

Michimasa Okubo

Kenji Goto

Takeyuki Sagae

Yuki Horinouchi

Akira Inoue

Mizuki Nihei

Kojiro Shiraishi

Kunihiro Shima

Yuya Kato

Kunihiro Tanaka

Eiichi Honda

Kenichi Hamada

Emi Takegawa

The present invention relates to a medical Pt&#x2014;W alloy, containing 10 mass % or more and 15 mass % or less of W, with the balance being Pt and inevitable impurities, in which a Zr content is 1000 ppm or less. Limiting the Zr content can improve workability, particularly workability at the stage of hot working. Regarding impurity control, further limiting a Ca content to 250 ppm or less can provide more suitable workability. The present invention is good in workability in processing into a wire included in an embolic coil, a guide wire or the like.

Medical Pt-W alloy

The present invention is drawn to a medical Pt alloy wire, made of a Pt&#x2014;W alloy containing 10% by mass or more and 15% by mass or less of W, a balance of Pt, and inevitable impurities. The Pt alloy wire has Vickers hardness of 400 Hv or more and 600 Hv or less, and has hardness and strength superior to those of a conventional Pt alloy wire having the same composition. The Pt alloy wire of the present invention has properties preferable as a coil applied to an embolic coil or a guide wire or the like, and is also good in workability in secondary processing for producing such a medical tool.

Medical Pt alloy wire and medical Pt alloy coil

The present invention is an embolization coil having an optimum morphological stability. The embolization coil includes a wire material made of an Au&#x2014;Pt alloy. The wire material constituting the embolization coil has such a composition that a Pt concentration is 24 mass % or more and less than 34 mass %, with the balance being Au. The wire material has such a material structure that a Pt-rich phase of an Au&#x2014;Pt alloy having a Pt concentration of 1.2 to 3.8 times a Pt concentration of an &#x3b1; phase is distributed in an &#x3b1; phase matrix. The wire material has a bulk susceptibility of &#x2212;13 ppm or more and &#x2212;5 ppm or less. In a material structure of a transverse cross-section of the wire material, an average value of two or more average crystal particle diameters measured by a linear intercept method is 0.20 &#x3bc;m or more and 0.35 &#x3bc;m or less.

Embolization coil and method for producing embolization coil

The present invention relates to a medical Au&#x2014;Pt&#x2014;Pd alloy including Au, Pt, Pd, and inevitable impurities. The alloy has an alloy composition inside a polygon (A1-A2-A3-A4-A5-A6) surrounded by straight lines connected at point A1 (Au: 37.9 atom %, Pt: 0.1 atom %, and Pd: 62 atom %), point A2 (Au: 79.9 atom %, Pt: 0.1 atom %, and Pd: 20 atom %), point A3 (Au: 79.9 atom %, Pt: 20 atom %, and Pd: 0.1 atom %), point A4 (Au: 69.9 atom %, Pt: 30 atom %, and Pd: 0.1 atom %), point A5 (Au: 49 atom %, Pt: 30 atom %, and Pd: 21 atom %), and point A6 (Au: 39 atom %, Pt: 40 atom %, and Pd: 21 atom %) in a Au&#x2014;Pt&#x2014;Pd ternary state diagram. The metal structure of the alloy is optimized, and the metal structure is close to a single-phase structure, and has little precipitation of a Au-rich phase and a Pt-rich phase different in composition from a mother phase.

Medical Au-Pt-Pd alloy

Growing community of inventors

Isehara, Japan

Michimasa Okubo