US 12,330,956 B2
Method of producing annealing separator, annealing separator, and grain-oriented magnetic steel
Xingdong Wang, Takamatsu (JP)
Assigned to SETOLAS HOLDINGS, INC., Takamatsu (JP)
Appl. No. 18/269,533
Filed by SETOLAS HOLDINGS, INC., Kagawa (JP)
PCT Filed Sep. 27, 2021, PCT No. PCT/CN2021/120926
§ 371(c)(1), (2) Date Jun. 23, 2023,
PCT Pub. No. WO2022/262144, PCT Pub. Date Dec. 22, 2022.
Claims priority of application No. 202110675696.8 (CN), filed on Jun. 18, 2021.
Prior Publication US 2024/0286914 A1, Aug. 29, 2024
Int. Cl. C01F 5/08 (2006.01)
CPC C01F 5/08 (2013.01) [C01P 2004/61 (2013.01); C01P 2004/62 (2013.01); C01P 2006/16 (2013.01); C01P 2006/22 (2013.01); C01P 2006/80 (2013.01)] 7 Claims
OG exemplary drawing
 
1. A method of producing an annealing separator, wherein the method comprises:
step (1) in which magnesium oxide and an ammonium salt solution are mixed and reacted to prepare a magnesium salt solution and ammonia, and then a purified magnesium salt solution and ammonia are reacted to obtain magnesium hydroxide,
step (2) in which one portion of an obtained magnesium hydroxide is subjected to high temperature ageing at 155 to 230° C. while another portion of the obtained magnesium hydroxide is subjected to low temperature ageing at 10 to 100° C., and
step (3) in which the magnesium hydroxide aged under different conditions are mixed and burned to obtain magnesium oxide for use as an annealing separator.