Security device formed by printing with special effect inks

    公开(公告)号:US11504990B2

    公开(公告)日:2022-11-22

    申请号:US16434990

    申请日:2019-06-07

    摘要: A security device is disclosed that has an image formed upon a substrate. The image has a first printed region and a second different printed region both printed with a same ink formulation of field alignable flakes. At least one of the printed regions has optically variable effects. One of the first and second printed regions at least partially surrounds the other. The second printed region is formed of thin parallel lines and the first printed region has substantially wider lines than are printed in the second printed region. The area density of the ink in a line in the first group of wider lines is greater than the area density of a line in the second group of narrower lines. A surprising effect of this image is that particles or flakes in the ink are field aligned so as to produce a visible kinematic dynamic effect visible in the first region and not visible in the second region when the image is tilted or rotated.

    Durable optical interference pigment with a bimetal core

    公开(公告)号:US10031269B2

    公开(公告)日:2018-07-24

    申请号:US15283917

    申请日:2016-10-03

    IPC分类号: C01B21/064 G02B5/28 G02B5/00

    CPC分类号: G02B5/288 G02B5/003 G02B5/285

    摘要: In a plurality of asymmetric color-shifting flakes, each flake has an asymmetric magnetic core with a magnetic layer visible on the first side of the core and a non-magnetic reflector layer on the magnetic layer, visible on the second side of the core. The flake has a spacer layer and an absorber layer on the first side of the core, and also a spacer layer and an absorber layer on the second side of the core, for providing color shifting effects. The material of the magnetic layer is different from the material of the reflector layer, and may be more stable when exposed to a chemical. When a coating with the asymmetric color-shifting flakes is exposed to the chemical, it may have better optical performance than a coating with symmetric color-shifting flakes.