The subject is to shown a liquid crystal display device that has characteristics such as a short response time, a large voltage holding ratio, a low threshold voltage, a large contrast ratio, a long service life and a small flicker rate. The disclosure relates to a liquid crystal display device having an electrode group formed on one or both of a pair of substrates that are opposed to each other, and a plurality of active devices connected to the electrode group, and a liquid crystal alignment film formed on the opposing surfaces of the pair of substrates, and a liquid crystal composition sandwiched in between the pair of substrates, wherein the liquid crystal alignment film includes a polymer having a photodegradable group, and the liquid crystal composition includes at least one compound selected from the group consisting of compounds represented by formula (1) as a first component: ##STR00001##

The invention relates to a liquid-crystalline medium comprising at least one compound of the formula I, ##STR00001##
in which
R.sup.1 and R.sup.2 have the meanings indicated in Claim 1,
and to the use thereof in electro-optical liquid-crystal displays.

A main object of the present invention is to provide a birefringence improving agent that can realize a satisfactory white display even in a liquid crystal display device in which a ferroelectric liquid crystal composition is used and which can reduce the birefringence and has a large cell gap; a ferroelectric liquid crystal composition and a liquid crystal display device that use the birefringence improving agent; and a compound that can be used in a ferroelectric liquid crystal composition.

The present invention provides a manufacture method of a liquid crystal display panel. The graphene/PEDOT:PSS composite transparent conductive films replace the traditional ITO transparent conductive films, and a polar material is mixed in the liquid crystal compound of the liquid crystal display panel. The structural formula of the polar material is A-B, wherein the main function of the head group A is to create the larger intermolecular force between the polar material and the graphene/PEDOT:PSS composite transparent conductive films, and the main function of the tail group B is similar with the function of the PI branch to vertically align the liquid crystal molecules in the steric hindrance manner to act the effect of the vertical alignment; i.e. the polar material can generate a larger intermolecular force with the graphene/PEDOT:PSS composite transparent conductive films, and is vertically aligned on the TFT substrate and the CF substrate.

A liquid crystal compound comprising a specific compound having a positive dielectric anisotropy as the first component, and a specific compound having a low viscosity as a second component. Further, the liquid crystal compound may contain a specific compound having a positive dielectric anisotropy as the third component, a specific compound having a maximum temperature or a low viscosity as the fourth component, or a specific compound having a negative dielectric anisotropy as the fifth component.

The subject is to shown a liquid crystal display device that has characteristics such as a short response time, a large voltage holding ratio, a low threshold voltage, a large contrast ratio, a long service life and a small flicker rate. The disclosure relates to a liquid crystal display device having an electrode group formed on one or both of a pair of substrates that are opposed to each other, and a plurality of active devices connected to the electrode group, and a liquid crystal alignment film formed on the opposing surfaces of the pair of substrates, and a liquid crystal composition sandwiched in between the pair of substrates, wherein the liquid crystal alignment film includes a polymer having a photodegradable group, and the liquid crystal composition includes at least one compound selected from the group consisting of compounds represented by formula (1) as a first component:

##STR00001##

A liquid crystal composition satisfying at least one of characteristics such as a high maximum temperature of nematic phase, a low minimum temperature of nematic phase, small viscosity, suitable optical anisotropy, large positive dielectric anisotropy, large specific resistance, high stability to UV light and heat or a large elastic constant, or having a suitable balance regarding at least two of the characteristics, and an AM device having a short response time, a large voltage holding ratio, a low threshold voltage, a large contrast ratio and a long service life, etc. are described. The composition has a nematic phase and contains an additive that can suppress formation of an impurity, and a specific compound having large dielectric anisotropy as a first component, and may contain a specific compound having a high maximum temperature or small viscosity as a second component. The AM device is an LCD device including the composition.

The present disclosure provides a liquid crystal composition and a display panel using the same. The liquid crystal composition includes a first compound represented by the following formula (I-A) or formula (I-B), a second compound represented by the following formula (II-A) or formula (II-B), a third compound represented by the following formula (III-A) or formula (III-B), and a fourth compound represented by the following formula (IV).

##STR00001##