US 12,379,529 B2
Magnetic pigment flake, optically variable ink, and anti-falsification article
Hongbao Sun, Huizhou (CN); Qianyun Sun, Huizhou (CN); Zhangrong Chen, Huizhou (CN); and Shuo Pan, Huizhou (CN)
Assigned to HUIZHOU FORYOU OPTICAL TECHNOLOGY CO., LTD., Huizhou (CN)
Filed by HUIZHOU FORYOU OPTICAL TECHNOLOGY CO., LTD., Huizhou (CN)
Filed on Jun. 30, 2022, as Appl. No. 17/853,944.
Application 17/853,944 is a continuation of application No. PCT/CN2021/103887, filed on Jun. 30, 2021.
Claims priority of application No. 202110210021.6 (CN), filed on Feb. 24, 2021.
Prior Publication US 2022/0334295 A1, Oct. 20, 2022
Int. Cl. G02B 5/00 (2006.01); B42D 25/369 (2014.01); B42D 25/378 (2014.01); C09C 1/00 (2006.01); C09D 11/037 (2014.01); C09D 11/50 (2014.01); G02B 5/02 (2006.01); G02B 5/22 (2006.01); G02B 5/28 (2006.01)
CPC G02B 5/0242 (2013.01) [B42D 25/369 (2014.10); B42D 25/378 (2014.10); C09C 1/0015 (2013.01); C09D 11/037 (2013.01); C09D 11/50 (2013.01); G02B 5/008 (2013.01); G02B 5/0284 (2013.01); G02B 5/22 (2013.01); G02B 5/28 (2013.01); C01P 2004/20 (2013.01); C01P 2004/80 (2013.01); C01P 2006/42 (2013.01); G02B 2207/101 (2013.01)] 19 Claims
OG exemplary drawing
 
1. A magnetic pigment flake, comprising:
a filtering film layer, with a magnetic or magnetizable material; and
a metal nanoparticles layer, formed on a surface of the filtering film layer;
wherein the metal nanoparticles layer has a light scatter-enhancing property with a wavelength selectivity for incident light, the metal nanoparticles layer is configured to generate scattered light enhanced by a local surface plasmon resonance under an irradiation of visible light exceeding a predetermined intensity, and the filtering film layer has a Fabry Perot interference cavity; a color of the metal nanoparticles layer under the local surface plasmon resonance in response to the metal nanoparticles layer being irradiated by the visible light exceeding the predetermined intensity is different from a color of the metal nanoparticles layer under the local surface plasmon resonance in response to the metal nanoparticles layer being irradiated by the visible light below the predetermined intensity.