Provided is a composition which can be used for formation of an optical film having high quality and a high dichroic ratio even after the composition is stored for a predetermined period of time. The composition includes a compound represented by the general formula (A) and a compound represented by the general formula (B), wherein R.sup.1a in the general formula (A) and R.sup.1b in the general formula (B) are mutually different groups.

R.sup.1a—Ar.sup.1a—N═N—Ar.sup.2a—N═N—Ar.sup.3a—R.sup.10a   (A)

R.sup.1b—Ar.sup.1b—N═N—Ar.sup.2b—N═N—Ar.sup.3b—R.sup.10a   (B)

Provided is an optical film which has a maximum absorption at a wavelength in the range of 600 to 680 nm, has a high dichroic ratio, and is excellent in light resistance. The optical film includes: a polymer of a polymerizable liquid crystal compound; and a compound represented by the following general formula (1).

##STR00001##

Shown is a liquid crystal composition satisfying at least one of characteristics such as high maximum temperature, low minimum temperature, small viscosity, suitable optical anisotropy, large dielectric anisotropy and small frequency dependence, or has a suitable balance regarding at least two of the characteristics, and an AM device including the composition. The liquid crystal composition contains a specific compound having large positive dielectric anisotropy as a first component, and a specific compound having small viscosity as a second component, and may contain a specific compound having high maximum temperature or small viscosity as a third component, a specific compound having positive dielectric anisotropy as a fourth component or a specific compound having negative dielectric anisotropy as a fifth component.

Shown is a liquid crystal composition satisfying at least one of characteristics such as a high maximum temperature, a low minimum temperature, a small viscosity, a suitable optical anisotropy and a large dielectric anisotropy, or has a suitable balance regarding at least two of the characteristics, and an AM device including the composition. The liquid crystal composition contains a specific compound having large negative dielectric anisotropy as a first component, and a specific compound having small viscosity as a second component, and may contain a specific compound having negative dielectric anisotropy as a third component, a specific compound having a high maximum temperature or small viscosity as a fourth component or a specific compound having a polymerizable group as an additive component.

The instant invention relates to liquid crystalline media comprising a chiral component, component A, consisting of one or more chiral compounds, optionally, a bimesogenic component, component B, consisting of one or more bimesogenic compounds, a liquid crystalline component, component C, consisting of one or more liquid crystalline, respectively mesogenic compounds, and a reactive mesogenic component, component D, comprising, one or more reactive mesogenic compounds,
as defined in claim 1, to their stabilization by polymerization and to the polymer-stabilised liquid crystal materials, as well as to liquid crystal displays comprising these liquid crystal media, respectively these stabilized materials, especially to USH-displays and in particular to active matrix displays and, last not least, to the processes of preparation of the respective composite systems and of the displays comprising these systems.

The present invention relates to benzotriazole derivatives selected from the group of compounds of formulae Ia, Ib and Ic as defined in claim 1, to mesogenic media comprising the compounds of formulae Ia, Ib and Ic, and to the use of these compounds and mesogenic media in optical, electronic and electro-optical applications, in particular in devices for regulating the passage of energy from an outside space into an inside space, for example in windows.

The present invention relates to mesogen compounds that include a first mesogen (Mesogen-1) and a second mesogen (Mesogen-2) that are connected by a linking group (-L-), as represented by the following Formula (I):

##STR00001##

Mesogen-1, and optionally Mesogen-2, each independently include the following terminal group,

##STR00002##

where R is hydrogen, alkyl, or alkoxy. Mesogen-2 optionally includes a terminal group P-, which is selected from R, acrylate, methacrylate, trihalomethacrylate, oxirane, hydroxyl, carboxylic acid, and carboxylic acid ester. Mesogen-1 and Mesogen-2 together include a total of at least seven, or at least eight, cyclic groups. In some cases, Mesogen-1 and Mesengen-2 are the same. The present invention also relates to liquid crystal compositions that include such mesogen compounds, and to optical elements that include such mesogen compounds.

Shown is a liquid crystal composition satisfying at least one of characteristics such as a high maximum temperature, a low minimum temperature, a large elastic constant, a suitable optical anisotropy and a large negative dielectric anisotropy, or has a suitable balance regarding at least two of the characteristics, and an AM device including the composition. The liquid crystal composition may contain a specific compound having a high maximum temperature, a low minimum temperature, a large elastic constant and a large negative dielectric anisotropy as a first component, a specific compound having a high maximum temperature or a small viscosity as a second component, a specific compound having negative dielectric anisotropy as a third component, or a specific compound having a polymerizable group as an additive component.

A problem is to provide a liquid crystal compound satisfying at least one physical property such as high stability to heat and light, a high clearing point (or high maximum temperature), a low minimum temperature of a liquid crystal phase, small viscosity, suitable optical anisotropy, large dielectric anisotropy, a suitable elastic constant and excellent compatibility with other liquid crystal compounds, a liquid crystal composition containing the compound and a liquid crystal display device including the composition. A solution is a compound represented by formula (1). ##STR00001## In which, R.sup.1 is alkyl having 1 to 10 carbons or the like; Z.sup.1, Z.sup.2 and Z.sup.3 are independently a single bond, —COO—, —OCH.sub.2—, —CF.sub.2O— or the like, and at least one of Z.sup.1, Z.sup.2 and Z.sup.3 is —CF.sub.2O—; X.sup.1 is hydrogen, fluorine, —CF.sub.3 or —OCF.sub.3; and L.sup.1, L.sup.2, L.sup.3 and L.sup.4 are independently hydrogen, fluorine or chlorine.

A compound having a maximum absorption in a wavelength range of 350 nm to 550 nm that functions as a dichroic dye is provided. In particular, a compound represented by formula (1) is provided. In the compound represented by formula (1), R.sup.1 represents a hydrogen atom or the like; R.sup.2 represents an acyl group having 1 to 20 carbon atoms or the like; R.sup.3 represents a hydrogen atom or the like; and Y represents a group of formula (Y1). In the group of formula (Y1), * represents a bonding site with N, or a group of formula (Y2); and in the group of formula (Y2), * represents a bonding site with N; P.sup.1 and P.sup.2 each independently represent —S— or the like; and Q.sup.1 and Q.sup.2 each independently represent ═N— or the like.

##STR00001##