Special effect pigments provide unusual optical effects that are used for a variety of applications including jewelry, cosmetics, and coatings. Birefringent, pearlescent and angle-dependent color are all possible through the selection and orientation of nanoparticles. Structural color is another class of pigments where the color is obtained through the periodic ordering of nanoscale features, similar to the opalescence of a butterfly wing.
Nanoparticles for special effect pigments
Plasmonic nanoparticles have unique optical properties that are a function of the size and shape of the nanoparticle. A solution of gold nanoparticles is ruby red in color while silver is a vibrant yellow. By using other shape geometries such as rods, plates and shells, the optical response can be tuned throughout the visible and infrared regions of the spectrum. An unusual property of plasmonic nanoparticles is that the relative contributions of scattering and absorption is a function of the nanoparticle size, allowing for an additional level of control over the perceived color and appearance. In addition to plasmonic effects, artificial opals – colloidal crystals of uniformly sized nanoparticles – have unique color effects due to photonic effects.
How We Can Help
NanoComposix has the world’s largest library of plasmonic nanoparticles, with each particle having its own unique optical color. We have integrated these plasmonic nanoparticles into thin films, plastics, coatings, and paints. Unlike many organic dye colorants, the nanoparticles are non-fading, even under harsh UV-exposure conditions. In addition, we have extremely monodisperse silica, gold, and magnetic nanoparticles that will self-assemble into colloidal crystals to provide angle-dependent optical effects.
