Abstract: A security device includes a plurality of diffractive surface elements arranged on a carrier element. A surface covered by the diffractive surface elements on the carrier element can occupy at least a partial region of the carrier element. Each individual diffractive surface element can have a three-dimensional surface structure. A portion of the plurality of the diffractive surface elements can form a first surface element group including the portion of the plurality of diffractive surface elements, and an orientation of the diffractive surface elements in the first surface element group can be matched to each other wherein together they make a single first image point of an associated first symbol to be represented visible to an observer under particular observation conditions.

Abstract: A security device includes a plurality of diffractive surface elements arranged on a carrier element. A surface covered by the diffractive surface elements on the carrier element can occupy at least a partial region of the carrier element. Each individual diffractive surface element can have a three-dimensional surface structure. A portion of the plurality of the diffractive surface elements can form a first surface element group including the portion of the plurality of diffractive surface elements, and an orientation of the diffractive surface elements in the first surface element group can be matched to each other wherein together they make a single first image point of an associated first symbol to be represented visible to an observer under particular observation conditions.

Abstract: A security device includes a plurality of diffractive surface elements arranged on a carrier element. Each individual diffractive surface element can have a three-dimensional surface structure. A portion of the plurality of the diffractive surface elements can form a first surface element group. An orientation of the diffractive surface elements in the first surface element group can be matched to each other wherein they make a first point of an associated symbol to be represented visible. A plurality of additional surface element groups each can make a respective additional point of the symbol to be represented visible. The symbol can include a sum of all points represented by the first surface element group and the plurality of additional surface element groups. A movement of the symbol can be perceived by the continuous change in an angle of incidence of the light or an observation angle.

Abstract: A security device includes a plurality of diffractive surface elements arranged on a carrier element. Each individual diffractive surface element can have a three-dimensional surface structure. A portion of the plurality of the diffractive surface elements can form a first surface element group. An orientation of the diffractive surface elements in the first surface element group can be matched to each other wherein they make a first point of an associated symbol to be represented visible. A plurality of additional surface element groups each can make a respective additional point of the symbol to be represented visible. The symbol can include a sum of all points represented by the first surface element group and the plurality of additional surface element groups. A movement of the symbol can be perceived by the continuous change in an angle of incidence of the light or an observation angle.

Abstract: A security device for improving the security against falsification of articles has a carrier element. Arranged on the upper side of the carrier element are a large number of diffractive surface elements. The surface elements respectively form a number of surface element groups, surface structures of which are made to match one another in such a way that they show a point of the symbol to be represented over an entire observation sphere. By changing the angle of incidence of the light and/or the angle of observation of an observer, a continuous movement of the symbol in the observation sphere is perceived by the observer.

Abstract: Compounds of general formula (I), wherein R signifies hydrogen, halogen, cyano, isothiocyanato, or alkyl, alkenyl or alkynyl with 1 to 15 carbon atoms, which is unsubstituted or substituted with at least one of halogen, cyano and/or trifluoromethyl and in which one or more non-adjacent --CH.sub.2 -- group(s) can be replaced by --O--, --S--, --CO--, --COO-- and/or --OOC--; Q represents alkylene with 2 to 10 carbon atoms, which is unsubstituted or substituted with at least one fluorine and in which one --CH.sub.2 -- group can be replaced by --O--, --S--, --COO--, or --OOC--, or --CH.sub.2 --, --CF.sub.2 --, --CHF-- or a single covalent bond; A.sup.1, A.sup.2, A.sup.

Abstract: Compounds of the formula ##STR1## wherein n stands for the number 0 or 1; rings A, B and C each independently represent trans-1,4-cyclohexylene, trans-1,3-dioxane-2,5-diyl or unsubstituted or fluoro-substituted 1,4-phenylene; R.sup.1 denotes 3E-alkenyl with 4 to 12 carbon atoms, 4-alkenyl with 5 to 12 carbon atoms or, when ring A represents trans-1,4-cyclohexylene or trans-1,3-dioxane-2,5-diyl, also 1E-alkenyl with 2 to 12 carbon atoms; and R.sup.2 is hydrogen or C.sub.1 -C.sub.10 -alkyl, their manufacture as well as liquid crystalline mixtures which contain such compounds and their use for electro-optical purposes.

Abstract: Compounds of the formula ##STR1## wherein n stands for the number 0 or 1; rings A, B and C each independently represent trans-1,4-cyclohexylene, trans-1,3-dioxane-2,5-diyl or unsubstituted or fluoro-substituted 1,4-phenylene; R.sup.1 denotes 3E-alkenyl with 4 to 12 carbon atoms, 4-alkenyl with 5 to 12 carbon atoms or, when ring A represents trans-1,4-cyclohexylene or trans-1,3-dioxane-2,5-diyl, also 1E-alkenyl with 2 to 12 carbon atoms; and R.sup.2 is hydrogen or C.sub.1 -C.sub.10 -alkyl,their manufacture as well as liquid crystalline mixtures which contain such compounds and their use for electro-optical purposes.