	US 11,694,827 B2
	Light-colored magnetic particles having improved durability and chemical resistance
Hong Keon Kim, Daejeon (KR); Won Gyun Choe, Daejeon (KR); Su Dong Kim, Daejeon (KR); Hyun Soo Kim, Daejeon (KR); E Den Kim, Gwangju (KR); Hye Jun Choi, Daejeon (KR); and Ju Hee Kang, Daejeon (KR)
Assigned to Korea Minting, Security Printing & ID Card Operating Corp., Daejeon (KR)
Appl. No. 16/958,308
Filed by KOREA MINTING, SECURITY PRINTING & ID CARD OPERATING CORP., Daejeon (KR)
PCT Filed Nov. 8, 2018, PCT No. PCT/KR2018/013521 § 371(c)(1), (2) Date Jun. 26, 2020, PCT Pub. No. WO2019/132232, PCT Pub. Date Jul. 4, 2019.
Claims priority of application No. 10-2017-0183726 (KR), filed on Dec. 29, 2017.
Prior Publication US 2020/0357544 A1, Nov. 12, 2020
Int. Cl. H01F 1/047 (2006.01); B42D 25/29 (2014.01); B42D 25/369 (2014.01); C09D 11/037 (2014.01); C22C 38/16 (2006.01); C22C 38/06 (2006.01); H01F 1/09 (2006.01); B22F 1/16 (2022.01); B22F 1/145 (2022.01); B22F 1/17 (2022.01); B22F 1/052 (2022.01)

CPC H01F 1/09 (2013.01) [B22F 1/052 (2022.01); B22F 1/147 (2022.01); B22F 1/16 (2022.01); B22F 1/17 (2022.01); B42D 25/29 (2014.10); B42D 25/369 (2014.10); C09D 11/037 (2013.01); H01F 1/047 (2013.01)]

5 Claims

1. A magnetic particle consisting of:

a magnetic core;

a zirconium oxide coating layer formed on the magnetic core; and

a silver coating layer formed on the zirconium oxide coating layer,

wherein the silver coating layer has a silver content of 10 to 20% by weight relative to a weight of the magnetic core,

wherein the magnetic core includes one or more selected from the group consisting of Fe, Cu, Al, Ni, Co, Nb, Nd, Si, B, Cr, and Sm,

wherein the magnetic particle has a reflectance of 50 to 70% at a wavelength of 900 nm, and

wherein the zirconium oxide coating layer of the magnetic particle is not completely coated with the silver coating layer of the magnetic particle, and a part of a surface of the zirconium oxide coating layer of the magnetic particle is an outside of the magnetic particle.