Polar Nematic Materials for STN-LCDs

This interpretation was confirmed to some extent by experimental results, since it had been found that nematic mixtures composed of apolar nematic compounds and polar nematic compounds (nitriles) consist of a number of unassociated polar and non-polar monomers as well as associated polar dimers. This not only gives rise to a high value for the observed dielectric anisotropy of the mixture due to the non-associated polar compounds, but also 

Parentheses represent a monotropic transition temperature. Measured at a reduced temperature of 0.96 x Tn-i- Extrapolated value from a 10% concentration in a nematic mixture. 

Compounds with a trans carbon-carbon double bond at an odd number (1 and 3) of carbon atoms away from the molecular core e.g. 74 and 78), see Table 3.14, exhibit a high nematic clearing point even higher than that of the reference material (41) with no double bond in the terminal chain. The analogous cis- 

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