Patent · US Expired

Document security method utilizing microdrop combinatorics, ink set and ink composition used therein, and product formed

US6786954B1 · kind B1 · utility

29Cited by
13References
34Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 9, 2000
Grant dateSep 7, 2004
Priority date
Expiry dateMay 9, 2020

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S462/903
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

Disclosed are sets of ink components, and ink compositions, useful for printing markings, on security documents, that are relatively resistant to counterfeiting. Also disclosed are the security documents formed, a method of printing and a method of authenticating the printed material. The markings, formed of the ink compositions have a spectral response that deviates from a predicted spectral response when linearly additively combining spectral responses of components of the ink composition, so that it becomes difficult to reverse-engineer the ink composition from the markings. Use of plural different markings, with each marking being a microdot, increases difficulty in counterfeiting. By forming a template of spectral responses of the original pattern, spectral responses of a pattern on an unknown document can be compared to the spectral responses on the template for determining whether the unknown document is authentic. Formation of the markings is facilitated using an inkjet printer.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.