Liquid crystal devices
View Patent ↗There is provided a liquid crystal device that exhibits excellent response properties over a wide temperature range even when the weight percentage of the polymerizable monomer used for generating polymers is decreased. The liquid crystal device according to the present invention is a liquid crystal device which includes a first substrate and a second substrate, at least one of which has an electrode group formed thereon for driving liquid crystals; and a liquid crystal layer sandwiched between the first substrate and the second substrate, in which the liquid crystal layer contains a polymer which is eccentrically distributed on at least one substrate side among the first substrate and the second substrate.
1. A liquid crystal device comprising:
a first substrate and a second substrate, at least one of which has an electrode group formed thereon for driving a liquid crystal; and
a liquid crystal layer sandwiched between the first substrate and the second substrate;
wherein the liquid crystal layer contains a liquid crystal, a polymeric initiator, and a polymer which is eccentrically distributed on at least one substrate side among the first substrate and the second substrate;
wherein a solubility parameter of the polymeric initiator is at least 12.0 (cal/cm 3 ) 0.5 ;
wherein the solubility parameter of the polymeric initiator is larger than a solubility parameter of the liquid crystal; and
wherein a solubility parameter of an alignment layer formed on at least one of the first substrate and the second substrate is at least 12.0 (cal/cm 3 ) 0.5 .
2. The liquid crystal device according to claim 1 , wherein the content of the polymer in the liquid crystal layer is 2.0 wt % or smaller.
3. The liquid crystal device according to claim 1 , wherein the electrode group is formed on the first substrate and the second substrate is facing the first substrate.
4. The liquid crystal device according to claim 3 , wherein the liquid crystal device is an IPS-mode liquid crystal device.
5. The liquid crystal device according to claim 3 , wherein 70 wt % or more of the polymer is contained in a part of the liquid crystal layer close to one of the substrates.
6. The liquid crystal device according to claim 1 , wherein the polymer is generated by irradiating ultraviolet to a liquid crystal composition that contains a photo-polymerizable monomer and an ultraviolet absorbing agent between the first substrate and the second substrate so as to polymerize the photo-polymerizable monomer.
7. The liquid crystal device according to claim 6 , wherein the ultraviolet absorbing agent is an ultraviolet absorbing agent having liquid crystallinity.
8. The liquid crystal device according to claim 7 , wherein the ultraviolet absorbing agent contains a terphenyl group or a quaterphenyl group in its molecules.
9. The liquid crystal device according to claim 1 , wherein the polymer is generated by irradiating light to a liquid crystal composition that contains a photo-polymerizable monomer and the polymeric initiator having the solubility parameter of at least 12.0 (cal/cm 3 ) 0.5 disposed between the first substrate and the second substrate so as to polymerize the photo-polymerizable monomer.
10. The liquid crystal device according to claim 9 , wherein the polymeric initiator is a polymeric initiator having liquid crystallinity.
11. The liquid crystal device according to claim 1 , wherein the solubility parameter of the alignment layer formed on the one of the first substrate and the second substrate is larger than a solubility parameter of an alignment layer formed on the other substrate.