US 11,756,736 B2
Manufacturing method of ceramic powder
Chie Kawamura, Takasaki (JP); Kazumichi Hiroi, Takasaki (JP); and Osamu Hattori, Takasaki (JP)
Assigned to TAIYO YUDEN CO., LTD., Tokyo (JP)
Filed by TAIYO YUDEN CO., LTD., Tokyo (JP)
Filed on Oct. 14, 2021, as Appl. No. 17/501,817.
Application 17/501,817 is a division of application No. 16/882,342, filed on May 22, 2020, granted, now 11,177,073.
Application 16/882,342 is a division of application No. 16/155,623, filed on Oct. 9, 2018, abandoned.
Application 16/155,623 is a division of application No. 15/623,253, filed on Jun. 14, 2017, abandoned.
Claims priority of application No. 2016-125825 (JP), filed on Jun. 24, 2016.
Prior Publication US 2022/0037088 A1, Feb. 3, 2022
This patent is subject to a terminal disclaimer.
Int. Cl. C04B 35/468 (2006.01); H01G 4/12 (2006.01); H01G 4/30 (2006.01); B32B 18/00 (2006.01); C01G 23/00 (2006.01); C04B 35/626 (2006.01)
CPC H01G 4/30 (2013.01) [B32B 18/00 (2013.01); C01G 23/006 (2013.01); C04B 35/4682 (2013.01); C04B 35/62655 (2013.01); C04B 35/62685 (2013.01); H01G 4/1218 (2013.01); H01G 4/1227 (2013.01); C01P 2002/34 (2013.01); C01P 2002/50 (2013.01); C01P 2002/72 (2013.01); C01P 2002/88 (2013.01); C01P 2006/12 (2013.01); C04B 2235/3224 (2013.01); C04B 2235/3239 (2013.01); C04B 2235/3256 (2013.01); C04B 2235/3258 (2013.01); C04B 2235/3262 (2013.01); C04B 2235/3267 (2013.01); C04B 2235/3418 (2013.01); C04B 2235/5296 (2013.01); C04B 2235/5409 (2013.01); C04B 2235/663 (2013.01); C04B 2237/346 (2013.01); C04B 2237/68 (2013.01)] 4 Claims
OG exemplary drawing
 
1. A manufacturing method of ceramic powder comprising:
mixing a barium carbonate having a specific surface are of 15 m2/g or more, a titanium dioxide having a specific surface area of 20 m2/g or more, a first compound of a donor element having a larger valence than Ti, and a second compound of an acceptor element having a smaller valence than Ti and having a larger ion radium than Ti and the donor element; and
synthesizing barium titanate powder by calcining the barium carbonate, the titanium dioxide, the first compound and the second compound until a specific surface area of the barium titanate powder becomes 4 m2/g or more and 25 m2/g or less,
wherein:
a solid solution amount of the donor element with respect to the barium titanate is 0.05 mol or more and 0.3 mol or less on a presumption that an amount of the barium titanate is 100 mol and the donor element is converted into an oxide;
a solid solution amount of the accepter element with respect to the barium titanate is 0.02 mol or more and 0.2 mol or less on a presumption that the amount of the barium titanate is 100 mol and the acceptor element is converted into an oxide; and
relationships y≥−0.0003x+1.0106, y≤−0.0002x+1.0114, 4≤x≤25 and y≤1.0099 are satisfied when a specific surface area of the ceramic powder is “x” and an axial ratio c/a of the ceramic powder is “y”.