Tanaka Kikinzoku Kogyo K.k.

Takuya Hosoi

Nobuhisa Okamoto

Koichi Sakairi

Nobuyuki Akiyama

Shigekazu Onozumi

Akihiro Nakai

Akio Nagaoka

Keisuke Maeto

The aim of the present invention is to provide a metal powder for an electroconductive paste with which a low-resistance electrode film can be formed. One embodiment of the present invention relates to a platinum-containing or platinum-alloy-containing metal powder for an electroconductive paste, the metal powder including a metal element or metal elements other than Pt, wherein the metal elements other than Pt include at least Ca, and may further include Al and Zr, and the total content of the Ca, Al and Zr among the metal elements other than Pt is 10-900 mass ppm.

Metal powder

To be provided is a metal paste from which an electrode having high electrode activity as a sensor electrode of various gas sensors can be produced. The present invention is a metal paste for forming a gas sensor electrode obtained by dispersing a conductive particle including Pt or a Pt alloy and a ceramic powder including zirconia or stabilized zirconia, or any of zirconia and stabilized zirconia and one or more oxides of La, Ce, Pr, Nd, Sm, and Hf in a solvent, the metal paste further including an inorganic oxide particle containing alumina and an insoluble particle that is insoluble in the solvent, in which 0.5 or more to 3.0 mass % or less of the inorganic oxide particle and 1.0 to 5.0 mass % of the insoluble particle are dispersed based on the mass of the solid content of the conductive particle, the ceramic powder, the inorganic oxide particle, and the insoluble particle.

Metal paste for gas sensor electrode formation

The present invention relates to a gas sensor electrode including a conductive particle phase made of Pt or Pt alloy and a ceramic particle phase being mixed and dispersed, wherein a rate of content of the ceramic particle phase is 6.0 to 22.0 mass %, and a void ratio is 2.5 to 10.0%, and a dispersion degree of the conductive particle phase per length of 25 &#x3bc;m on the electrode surface is 0.60 to 0.85 &#x3bc;m, and a dispersion degree of the conductive particle phase in the electrode cross section per length of 100 &#x3bc;m in a direction parallel to the electrode surface is 2.0 to 4.0 &#x3bc;m. This electrode can be produced by firing a metal paste made by dispersing, in a solvent, a conductive particle having a core/shell structure in which a core particle such as Pt is covered with a ceramic shell and ceramic powder. The gas sensor electrode according to the present invention has a high electrode activity.

Sensor electrode, manufacturing method thereof, and metal paste for electrode formation

An object of the present invention is to provide a conductive fine particle for producing a metal paste that can produce an electrode film having a low resistance, and a metal paste utilizing the conductive fine particle. The present invention is a conductive particle for electrode formation having a core/shell structure, and the conductive particle comprises a core particle made of Pt or a Pt alloy and having a particle diameter of 10 to 200 nm, and a shell made of a ceramic containing AlOor ZrOand covers at least a part of the core particle, wherein the ceramic constituting the shell is added in an amount of 0.5 to 15% by weight based on the core particle to cover the core. The core particle is preferably Pt or a Pt alloy alloyed with Pd, Au, Ag, or Rh.

Conductive fine particle and metal paste for electrode formation and electrode

The present invention is an electroconductive particle for forming an electrode including a precious metal particle including Pt or a Pt alloy and having an average particle diameter of 50 to 150 nm, a first ceramic particle including AlOor ZrOdispersed in the precious metal particle and having an average particle diameter of 5 to 50 nm, and a second ceramic particle including AlOor ZrObonded to an outer periphery of the precious metal particle and having an average particle diameter of 5 to 50 nm. The sum of the volume of the first ceramic particle and the volume of the second ceramic particle is preferably 2 to 40 vol % based on the whole electroconductive particle. A metal paste containing the electroconductive particle according to the invention is one from which an electrode film of low resistance and excellent durability can be manufactured and further excellent in adherence and conformability to a substrate.

Growing community of inventors

Hiratsuka, Japan

Takuya Hosoi