The first liquid crystal materials were discovered in May 1888 by Dr. Friederich Reinitzer.
Ritzner called his novel discoveries "liquid crystals"
because the crystals they formed were very soft and were not significantly durable or stable.
Early color-related uses of cholesteric liquid crystals (CLCs) were in temperature dependent
applications. By the 1970's, CLCs had become durable and colorfast enough to appear in
consumer products like thermometer strips, inks, and ever fashionable mood rings.
But CLCs remained highly sensitive to chemical solvents, and more robust approaches were
needed to create
commercial CLC systems.
At the same time as color applications of liquid crystals were being developed,
the use of liquid crystals in polymer systems was also gathering steam. DuPont
commercialized the first liquid crystal polymer fiber, Kevlar, in 1975. In Kevlar, the
liquid crystal groups form the backbone of the polymer, giving it rigidity and strength. Cholesteric liquid phases, however,
do not occur in these materials.
Innovations at the end of the 1970's that enabled high molecular weight polymeric systems
to behave like low molecular weight systems finally helped to make durable temperature sensitive
cholesteric systems possible.
In 1991, Chelix's parent company Reveo patented the first process that used
the photopolymerization of reactive polymers with side chain mesogen groups to make durable
CLC pigments. This was a succesful marriage of the early but separate strides towards color-related
and polymer-based applications of liquid crystals.
Reveo continued its innovations in other CLC film and display
applications from 1992-1997, and Chelix continues this mission today.
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