The present invention relates to liquid-crystalline media comprising one or more pleochroic dyes and one or more compounds selected from the group of compounds of formulae I, II and III,

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in which the parameters have the meaning indicated in Claim 1, and to components comprising these media for high-frequency technology, in particular phase shifters and microwave array antennas.

Provided is a liquid crystal composition capable of suppressing a decrease in phase transition temperature from a smectic phase to a nematic phase and suppressing alignment defects in a liquid crystal cured layer thus formed, a liquid crystal cured layer, an optical film, a polarizing plate, and an image display device. The liquid crystal composition includes a liquid crystal compound exhibiting a smectic phase and a freezing point depressant, in which the liquid crystal compound is a compound represented by Formula (I) SP1-MG-SP2, and the liquid crystal composition satisfies Expression (1) |Am−Asl≥0.2 and Expression (2-1) in a case of Am≤As, Aa≥(Am+As)/2 or Expression (2-2) in a case of Am>As, Aa≤(Am+As)/2.

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).

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A composition for a polarization film including: a transparent resin having a boiling point of greater than or equal to 130° C.; and a dichroic dye represented by Chemical Formula 1, ##STR00001##

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.

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.

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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 of formula (1), R.sup.1 represents a hydrogen atom or the like; R.sup.2 represents a hydrogen atom or the like; R.sup.3 represents a hydrogen atom or the like; Z represents —CO— 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.

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A light valve that is operable in and electrically switchable between an optically clear and transparent state and an opaque state, wherein one or more polymerisable mesogenic compounds provided in a layer containing a liquid-crystalline medium that comprises one or more mesogenic compounds, one or more chiral compounds, one or more dichroic dyes and the one or more polymerisable mesogenic compounds are subjected to photopolymerisation. Further, a liquid-crystalline medium used in the method, a light valve obtained or respectively obtainable by carrying out the method, and the use of the light valve in mobile devices.

The embodiment of the present invention discloses a display panel, a manufacturing method thereof, and a display device. In the embodiment of the present invention, a liquid crystal layer of the display panel includes a plurality of dichroic dye liquid crystal microcapsules, a dichroic dye in dichroic dye liquid crystal microcapsules can absorb incident light such that when the display panel performs no signal transmission, the dichroic dye polymer network liquid crystal can effectively absorb incident light to lower a dark state transmittance of the display panel to further enhance contrast of the display panel and improve optical characteristics thereof.