The Cholesteric liquid crystal (CLC) pigments are made up of CLC films rather CLC polymers. The polymers are typically cross linked materials which have their molecules "locked" during the cholesteric phase. Now this enables the unique and brilliant optical properties of a liquid crystal to be exploited to the hilt in a solid pigment. Each of the flake in the pigment is a piece of microfilm in a platelet form. It has dimensions of around 5 micron in thickness. Cholesteric liquid crystal or CLC polymer film is kind of naturally reflective polarizer. If the center wavelength is set in a way, to be within the visible spectra, then it is possible to create color travel effects through a circular polarized reflection. A typical structure of CLC structure is given below:
For enabling a good special effect pigment, that is to be derived from a CLC (cholesteric liquid crystal technology), some sort of modification needs to be done to several properties of CLCs
Optical Properties of CLC Pigments
The Optical properties of CLC pigments can be best described with the help of the diagram that is given below. It is to be undersood here, that quite unlike the metal interference systems, CLCs can develop their color reflection through a single layer only.
CLC pigments show very good blue-shifting color travel as illustrated in this graphical representation.