US 11,945,254 B2
Security element
Nikolay A. Grigorenko, Basel (CH); and Michelle Richert, Basel (CH)
Assigned to BASF SE, Ludwigshafen am Rhein (DE)
Appl. No. 17/424,095
Filed by BASF SE, Ludwigshafen am Rhein (DE)
PCT Filed Jan. 16, 2020, PCT No. PCT/EP2020/051001
§ 371(c)(1), (2) Date Jul. 19, 2021,
PCT Pub. No. WO2020/152021, PCT Pub. Date Jul. 30, 2020.
Claims priority of application No. 19152705 (EP), filed on Jan. 21, 2019.
Prior Publication US 2022/0097437 A1, Mar. 31, 2022
Int. Cl. B42D 25/373 (2014.01); B42D 25/21 (2014.01); B42D 25/351 (2014.01); B42D 25/415 (2014.01); C08J 7/04 (2020.01); C08K 3/08 (2006.01)
CPC B42D 25/351 (2014.10) [B42D 25/21 (2014.10); B42D 25/373 (2014.10); B42D 25/415 (2014.10); C08J 7/0427 (2020.01); C08K 3/08 (2013.01); C08J 2367/02 (2013.01); C08J 2429/04 (2013.01); C08K 2003/0806 (2013.01); C08K 2201/003 (2013.01)] 18 Claims
 
1. A security, or decorative element, consisting of a transparent, or translucent substrate, and
on at least part of the substrate surface, a first layer, comprising transition metal particles having an average diameter of from 5 nm to 500 nm and a binder,
on at least part of the first layer a second layer, comprising an organic material and having a refractive index of from 1.2 to 2.3, and
having a thickness of from 20 to 1000 nm, wherein the transition metal is selected from the group consisting of silver, copper, gold and palladium, wherein the weight ratio of transition metal particles to binder in the first layer is in the range from 20:1 to 1:2 in case the binder is a polymeric binder, or wherein the weight ratio of transition metal particles to binder in the first layer is in the range from 5:1 to 1:15 in case the binder is an UV curable binder, wherein the security or decorative element, consisting of the substrate, the first and the second layer, exhibits on its coated side an intensive angle dependent color in reflection and the transmission color of the security or decorative element with and without the second layer is essentially the same and differs by not more than 5 AE*ab units.