Anti-Stokes (up-converting) pigments
Anti-Stokes pigments are luminescent materials which convert near infrared (NIR) laser light to visible (VIS) light. The anti-Stokes shift occurs when the emission is a shorter wavelength than the original excitation wavelength. Generally, the excitation wavelength is a sharply determined near infra-red laser light (980 nm or, in some cases, 940 nm). The effect shows up as a concentrated bright color spot. We offer anti-Stokes luminescent security pigments with high stability, good light fastness and fine particle size in order to enable offset printing. We also offer laser pens or handheld, easy to use detectors specialized for the detection of the anti-Stokes effect. Our detector shows the presence of the Anti-Stokes pigment with light and sound signals. These properties make anti-Stokes pigments highly effective for special applications in the field of authentication such as security taggants in paper, or polymer industries. We enable our customers to explore new ways of incorporating pigments into their materials, which can then be detected by dedicated sorting machines for accurate authentication, even if applied at low concentrations.