Abstract: In a hydrogen-containing tantalum powder of the present invention, a value obtained by dividing the hydrogen content (ppm) by the specific surface area (m2/g) is in the range of 10 to 100. This tantalum powder has a large specific surface area, and when the tantalum powder is used as an anode of a solid electrolyte capacitor, a solid electrolyte capacitor having a large capacitance and a low leakage current can be obtained.

Abstract: In a hydrogen-containing tantalum powder of the present invention, a value obtained by dividing the hydrogen content (ppm) by the specific surface area (m2/g) is in the range of 10 to 100. This tantalum powder has a large specific surface area, and when the tantalum powder is used as an anode of a solid electrolyte capacitor, a solid electrolyte capacitor having a large capacitance and a low leakage current can be obtained.

Abstract: There is provided a niobium alloy powder suitable for manufacturing solid electrolytic capacitors having small leakage currents and high capacitances, where the powder is obtained by enhancing the thermal stability of the niobium oxide coating film while improving the temperature dependence of the sintering behavior of the powder. The niobium alloy powder includes one or more of molybdenum, chromium, and tungsten each with a content of 0.002 to 20% by mass, and phosphorus and boron each with a content of 0.002 to 5% by mass, and moreover, includes hydrogen with a content of 0.005 to 0.10% by mass, the balance being substantially niobium; the specific surface area of the powder is from 1 to 20 m2/g; the powder has a cumulative pore volume of 0.2 ml/g or more; and the cumulative volume of the pores each having a diameter of 1 ?m or less makes up 10% or more and the cumulative volume of the pores each having a diameter of 10 ?m or less makes up 40% or more in relation to the total cumulative pore volume.

Abstract: There is provided a niobium alloy powder suitable for manufacturing solid electrolytic capacitors having small leakage currents and high capacitances, where the powder is obtained by enhancing the thermal stability of the niobium oxide coating film while improving the temperature dependence of the sintering behavior of the powder. The niobium alloy powder includes one or more of molybdenum, chromium, and tungsten each with a content of 0.002 to 20% by mass, and phosphorus and boron each with a content of 0.002 to 5% by mass, and moreover, includes hydrogen with a content of 0.005 to 0.10% by mass, the balance being substantially niobium; the specific surface area of the powder is from 1 to 20 m2/g; the powder has a cumulative pore volume of 0.2 ml/g or more; and the cumulative volume of the pores each having a diameter of 1 ?m or less makes up 10% or more and the cumulative volume of the pores each having a diameter of 10 ?m or less makes up 40% or more in relation to the total cumulative pore volume.

Abstract: There is provided a niobium powder to make a capacitor which is small leakage current, also limited leakage current even after application of thermal load, and high capacitance which is attained by enhancing the thermal stability of the niobium oxide coating film in the capacitor. The niobium powder includes at least one or more selected from molybdenum: 0.002 to 20% by mass, chromium: 0.002 to 10% by mass, and tungsten: 0.002 to 20% by mass; and hydrogen: 0.005 to 10% by mass, and the specific surface area of the powder is 1 to 10 m2/g. It is preferable that the niobium powder further includes magnesium: 0.002 to 1% by mass and aluminum: 0.002 to 1% by mass, and the average particle size of the secondary particles of the niobium powder is from 10 to 200 ?m.

Abstract: By adding a slight amount component to a niobium powder, the leakage current of a solid electrolytic capacitor is reduced and the capacitance thereof is improved, and thereby a solid electrolytic capacitor large in the capacitance and small dielectric loss tangent is manufactured. Specific resolution means are as follows. With a niobium powder that contains 1 ppm or more and 600 ppm or less of hydrogen; 1 ppm or more and 200 ppm or less of carbon; or 1 ppm or more and 50 ppm or less of nickel, and the balance substantially made of niobium as a raw material, a sintered body thereof is formed as an anode in a solid electrolytic capacitor 10.

Abstract: A niobium powder is provided for producing a niobium capacitor enhanced in the thermal stability of oxide films on niobium, with less leak current and less deterioration of leak current after application of thermal loads. The niobium powder contains form 0.005 to 0.10 mass % of hydrogen and from 0.002 to 5 mass % of sulfur and, further preferably, one or both of magnesium and aluminum in an amount from 0.002 to 1 mass % in total. The specific surface area of the powder is 1 to 10 m2/g and the average particle diameter of the secondary particles is 10 to 200 &mgr;m.

Abstract: A niobium powder is provided for producing a niobium capacitor enhanced in the thermal stability of oxide films on niobium, with less leak current and less deterioration of leak current after application of thermal loads. The niobium powder contains form 0.005 to 0.10 mass % of hydrogen and from 0.002 to 5 mass % of sulfur and, further preferably, one or both of magnesium and aluminum in an amount from 0.002 to 1 mass % in total. The specific surface area of the powder is 1 to 10 m2/g and the average particle diameter of the secondary particles is 10 to 200 &mgr;m.