The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 10, 2012
Filed:
Mar. 05, 2008
Hideyasu Ando, Kawasaki, JP;
Yasunori Kasuga, Tokyo, JP;
Hideyasu Ando, Kawasaki, JP;
Yasunori Kasuga, Tokyo, JP;
Kabushiki Kaisha Toshiba, Tokyo, JP;
Abstract
A ZnO varistor powder can be obtained with high operating voltage and excellent current-voltage nonlinear resistance characteristics. In the ZnO varistor powder, the main ingredient is zinc oxide (ZnO); and at least bismuth (Bi), cobalt (Co), manganese (Mn), antimony (Sb), nickel (Ni), and aluminum (Al), calculated as BiO, COO, MnO, SbO, NiO, and Al, are contained as accessory ingredients in amounts of 0.3 to 1.5 mol % BiO, 0.3 to 2.0 mol % CoO, 0.3 to 3 mol % MnO, 0.5 to 4 mol % SbO, 0.5 to 4 mol % NiO, and 0.0005 to 0.02 mol % Al. ZnO content is greater than or equal to 90 mol %; the bulk density is greater than or equal to 2.5 g/cc; the powder is a spherical powder in which the 50% particle diameter in the particle size distribution is 20 μm to 120 μm.