@misc { , title = {Liquid crystalline phases in suspensions of pigments in non-polar solvents}, abstract = {We will discuss colloid suspensions of pigments and compare their electro-optic properties with those of traditional dyed low molecular weight liquid crystal systems. There are several potential advantages of colloidal suspensions over low molecular weight liquid crystal systems: a very high contrast because of the high orientational order parameter of suspensions of rod shaped nano-particles, the excellent light fastness of pigments as compared to dyes and high colour saturations resulting from the high loading of the colour stuff. Although a weak `single-particle' electro-optic response can be observed in dilute suspensions, the response is very much enhanced when the concentration of the particles is sufficient to lead to a nematic phase. Excellent stability of suspensions is beneficial for experimental observation and reproducibility, but it is a fundamental necessity for display applications. We therefore discuss a method to achieve long term stability of dispersed pigments and the reasons for its success. Small angle X-ray scattering was used to determine the orientational order parameter of the suspensions as a function of concentration and the dynamic response to an applied electric field. Optical properties were investigated for a wide range of pigment concentrations. Electro-optical phenomena, such as field-induced birefringence and switching, were characterised. In addition, mixtures of pigment suspensions with small amounts of ferro uids show promise as future magneto-optical materials.}, isbn = {9789814619257}, pages = {847-870}, publicationstatus = {Published}, url = {https://uwe-repository.worktribe.com/output/902374}, keyword = {Centre for Fine Print Research, colloidal suspensions, liquid crystals, pigments, birefringence, X-ray scattering, magneto-optical response}, year = {2016}, author = {Klein, Susanne and Richardson, R. M. and Eremin, Alexey} editor = {Lagerwall, Jan PF and Scalia, Giusy} }