An optical film includes a cholesteric liquid crystal layer formed in a stripe-shaped pattern in which an optically anisotropic region having optical anisotropy and an optically isotropic region having optical isotropy are alternately disposed, a helical axis of a cholesteric liquid crystal in the optically anisotropic region is oriented in one axial direction tin a plane of the optical film, and the helical axis is oriented in a normal direction t of a boundary surface between the optically anisotropic region and the optically isotropic region.

An optical film includes a cholesteric liquid crystal layer formed in a stripe-shaped pattern in which an optically anisotropic region having optical anisotropy and an optically isotropic region having optical isotropy are alternately disposed, a helical axis of a cholesteric liquid crystal in the optically anisotropic region is oriented in one axial direction tin a plane of the optical film, and the helical axis is oriented in a normal direction t of a boundary surface between the optically anisotropic region and the optically isotropic region.

A method for producing a cholesteric liquid crystal based shell is provided. The method comprises producing a cholesteric liquid crystal shell, solidifying the cholesteric liquid crystal shell so as to obtain a solid shell and perforating the solid shell. Also provided is a cholesteric liquid crystal based solid shell comprising a perforation. A coating composition comprising a plurality of cholesteric liquid crystal based solid shells, an item comprising a tag that comprises the cholesteric liquid crystal based solid shells and a method for authenticating the item are also provided.

A method for producing a cholesteric liquid crystal based shell is provided. The method comprises producing a cholesteric liquid crystal shell, solidifying the cholesteric liquid crystal shell so as to obtain a solid shell and perforating the solid shell. Also provided is a cholesteric liquid crystal based solid shell comprising a perforation. A coating composition comprising a plurality of cholesteric liquid crystal based solid shells, an item comprising a tag that comprises the cholesteric liquid crystal based solid shells and a method for authenticating the item are also provided.

A method for fabricating micro-cell structures is provided and has providing a liquid crystal mixture; performing a heating step on the liquid crystal mixture at a temperature ranging from 45 C. to 150 C., performing a heat induced phase separation step on the liquid crystal mixture at a thermal phase separation temperature for a thermal phase separation titre such that the liquid crystal mixture forms liquid crystal particles and a network light-curing adhesive, wherein the thermal phase separation temperature and the thermal phase separation time are determined by a changing rate of a bright area ratio of the liquid crystal mixture; and performing a photo-curing step on the liquid crystal mixture by emitting an ultraviolet light so that a plurality of micro-cell structures are formed. The micro-cell structures with different transparency are fabricated based on different values of the thermal phase separation temperature and the thermal phase separation time.

A method for fabricating micro-cell structures is provided and has providing a liquid crystal mixture; performing a heating step on the liquid crystal mixture at a temperature ranging from 45 C. to 150 C., performing a heat induced phase separation step on the liquid crystal mixture at a thermal phase separation temperature for a thermal phase separation titre such that the liquid crystal mixture forms liquid crystal particles and a network light-curing adhesive, wherein the thermal phase separation temperature and the thermal phase separation time are determined by a changing rate of a bright area ratio of the liquid crystal mixture; and performing a photo-curing step on the liquid crystal mixture by emitting an ultraviolet light so that a plurality of micro-cell structures are formed. The micro-cell structures with different transparency are fabricated based on different values of the thermal phase separation temperature and the thermal phase separation time.

Provided is a polar compound having high chemical stability, high capability of aligning liquid crystal molecules, high solubility in a liquid crystal composition, and a large voltage holding ratio when used in a liquid crystal display device. The compound is represented by formula (1): ##STR00001##
in which, for example, R.sup.1 is alkyl having 1 to 15 carbons; MES is a mesogen group having at least one ring; Sp.sup.1 is a single bond or alkylene having 1 to 10 carbons; M.sup.1 and M.sup.2 are hydrogen; and R.sup.2 is a group represented by formulas (1a) to (1c): ##STR00002##
in which, Sp.sup.2 and Sp.sup.3 are a single bond or alkylene having 1 to 10 carbons; S.sup.1 is >CH; S.sup.2 is >C<; and X.sup.1 is OH.

Provided is a polar compound having high chemical stability, high capability of aligning liquid crystal molecules, high solubility in a liquid crystal composition, and a large voltage holding ratio when used in a liquid crystal display device. The compound is represented by formula (1): ##STR00001##
in which, for example, R.sup.1 is alkyl having 1 to 15 carbons; MES is a mesogen group having at least one ring; Sp.sup.1 is a single bond or alkylene having 1 to 10 carbons; M.sup.1 and M.sup.2 are hydrogen; and R.sup.2 is a group represented by formulas (1a) to (1c): ##STR00002##
in which, Sp.sup.2 and Sp.sup.3 are a single bond or alkylene having 1 to 10 carbons; S.sup.1 is >CH; S.sup.2 is >C<; and X.sup.1 is OH.

The present invention relates to liquid-crystalline media (LC media) having negative or positive dielectric anisotropy comprising self-aligning mesogens (SAMs) which effect homeotropic (vertical) alignment of the LC media at a surface or the cell walls of a liquid-crystal display (LC display). The invention therefore also encompasses LC displays having homeotropic alignment of the liquid-crystalline medium (LC medium) without conventional imide alignment layers. The LC media may be supplemented by a polymerisable or polymerised component, which serves for stabilisation of the alignment, for adjustment of the tilt angle and/or as passivation layer.

The present invention relates to liquid-crystalline media (LC media) having negative or positive dielectric anisotropy comprising self-aligning mesogens (SAMs) which effect homeotropic (vertical) alignment of the LC media at a surface or the cell walls of a liquid-crystal display (LC display). The invention therefore also encompasses LC displays having homeotropic alignment of the liquid-crystalline medium (LC medium) without conventional imide alignment layers. The LC media may be supplemented by a polymerisable or polymerised component, which serves for stabilisation of the alignment, for adjustment of the tilt angle and/or as passivation layer.