Abstract: Devices useful for storage of information which comprises mixtures of suitable chiral materials with nematic liquid crystals and in which by irradiation with light of two different wavelengths the chirality of the mixture can be reversibly switched between two stable states of different chirality, corresponding to two states of different optical properties.

Abstract: Lasting fragrant article formed by impregnating a pregnant with a composition prepared by compounding a single perfume or blend of perfumes with a compound represented by the general formula:R.sub.a Si(OR').sub.b (OR").sub.cwherein R, R', and R" represent hydrocarbon residues and R" represents a group which develops aroma in the form of R"OH; a+b+c=4; and c.gtoreq.1; or its product formed by hydrolysis or dehydration condensation. The fragrant article is characterized by the use of particular compounds, resulting in persistent aroma, and it is subject to very little change in the fragrance tone.

Abstract: A compound represented by the general formula:R.sub.s Si(OR').sub.t (OR").sub.4-s-twherein R represents methyl, ethyl, or vinyl; R'O represents ##STR1## R" represents methyl or ethyl; s represents 0 or 1; and t represents an integer of from 1 to 4; and fragrant agent formed by impregnating solid matter with a compound represented by the general formula:R.sup.3.sub.a Si(OR.sup.4).sub.b (OR.sup.5).sub.cwherein R.sup.3, R.sup.4 and R.sup.5 represent a hydrocarbon group, with the proviso that R.sup.5 is derived from an alcohol of the general formula R.sup.5 OH that develops aroma; and a, b and c are each an integer, or a derivative thereof.