公开(公告)号：US10166811B1

公开(公告)日：2019-01-01

申请号：US15928341

申请日：2018-03-22

Applicant: VORBECK MATERIAL CORP.

Inventor： John S Lettow ,  Dan Scheffer

IPC: B42D25/373 ,  B42D25/21 ,  B42D25/45 ,  B42D25/00 ,  B42D25/29 ,  B42D15/00 ,  B82Y30/00

Abstract: A combination comprising a document having an image applied thereto and a security device affixed to a surface of the document. The security device comprising a first layer applied on the image. The first layer comprising a first and a second portion in communication with a first and second image area of the image, respectively. The first layer comprising a coating composition comprising fully exfoliated single sheets of graphene. The first portion comprises: a first detectable property having a first value correlated with the fully exfoliated single sheets of graphene; a first X-ray diffraction pattern; and a first electrical conductivity. The second portion comprises a second detectable property comprising: a second value correlated with the fully exfoliated single sheets of graphene; a second X-ray diffraction pattern; and a second electrical conductivity. The first and second detectable properties are not equal and together create a distinctive signature.