Chemistry:Homogeneous alignment

From HandWiki

In liquid crystals homogeneous alignment, sometimes called planar alignment, is the state of alignment where molecules align in parallel to a substrate. The opposite method is homeotropic alignment.[1]

For planar alignment - polyimides can be used. One of the popular ones is PI-2555.

The surface has to be rubbed by paper or by a velvet or similar cloth in order to make the alignment axis parallel to the rubbing.[1] However the exact mechanism of this alignment is not entirely clear.

References

  1. 1.0 1.1 Jones, Lesley Parry (2012), Chen, Janglin; Cranton, Wayne; Fihn, Mark, eds., "Alignment Properties of Liquid Crystals" (in en), Handbook of Visual Display Technology (Berlin, Heidelberg: Springer Berlin Heidelberg): pp. 1390–92, doi:10.1007/978-3-540-79567-4_86, ISBN 978-3-540-79566-7, http://link.springer.com/10.1007/978-3-540-79567-4_86, retrieved 2025-01-08