Abstract: To detect an irradiated radiation efficiently, so that the dose can be measured with high sensitivity. A photochromic material comprising an illuminant(s) which emits a light when irradiated with a radiation and a diarylethene photochromic compound(s) having a specific structure, and a color dose meter employing it.

Abstract: A novel optical recording material is provided, which is capable of recording and reading an information signal by utilizing a change in the double refraction caused by a change in the molecular orientation of a side-chain type polymer liquid crystal which has an electrocyclic-reaction-type photochromic compound (or a residue thereof).

Abstract: A toy comprises a toy element comprising a photochromic layer which contains a photochromic compound having a photo memory function (color-memorizing photochromic property), maintains a coloring state by developing a color through the irradiation of ultraviolet rays or sunlight containing ultraviolet rays and changes into decolorizing state through its decolorization by the irradiation of visible light, and a color-changing means which contains at least one of an ultraviolet ray absorbent and a light-shading pigment capable of shading at least ultraviolet rays, changes the photochromic compound of the coloring state into decolorizing state by cutting off ultraviolet rays of sunlight and thereby effecting irradiation of visible light, and maintains the changed state, wherein a function to memorize and maintain coloring and decolorizing states alternately is expressed by arranging the color-changing means under such a condition that it is contacted or non-contacted with the photochromic layer.

Abstract: A photo-induced phase transition organic material is composed of a diheteroarylethene-based compound within which the photo-chromic reaction occurs in the crystalline state. The diheteroarylethene-based compound of the present invention reversibly changes in color with light irradiation and also changes in phase from the open-ring form in the crystalline state to the closed-ring form in the crystalline state, or from the closed-ring form in the crystalline state to the open-ring form in the crystalline state via the liquid state, and can be applicable to optical recording media, display panels, sensors, optical switch devices and the like, by taking advantages of its variations in color with light irradiation and also its changes in physical property, such as the refractive index and the permeability, with its changes in phase.

Abstract: A photochromic material having a ring opening quantum yield of 10−3 or lower which does not fade under ambient light is provided. The material comprises a compound belonging to the diheteroarylethene class. The compound has alkoxy group and aryl group on the heteroaryl group.

Abstract: A photo-induced phase transition organic material is composed of a diheteroarylethene-based compound within which the photo-chromic reaction occurs in the crystalline state. The diheteroarylethene-based compound of the present invention reversibly changes in color with light irradiation and also changes in phase from the open-ring form in the crystalline state to the closed-ring form in the crystalline state, or from the closed-ring form in the crystalline state to the open-ring form in the crystalline state via the liquid state, and can be applicable to optical recording media, display panels, sensors, optical switch devices and the like, by taking advantages of its variations in color with light irradiation and also its changes in physical property, such as the refractive index and the permeability, with its changes in phase.

Abstract: A near-field optical recording medium comprises a recording layer capable of writing, reading and erasing information using an evanescent light, the evanescent light having a beam spot size smaller than the wavelength of a source light, wherein the recording layer is a stable amorphous layer mainly comprising a photochromic compound having a glass transition point of 55° C. or higher and a molecular weight of 3000 or less.

Abstract: A photo-induced phase transition organic material is composed of a diheteroarylethene-based compound within which the photo-chromic reaction occurs in the crystalline state. The diheteroarylethene-based compound of the present invention reversibly changes in color with light irradiation and also changes in phase from the open-ring form in the crystalline state to the closed-ring form in the crystalline state, or from the closed-ring form in the crystalline state to the open-ring form in the crystalline state via the liquid state, and can be applicable to optical recording media, display panels, sensors, optical switch devices and the like, by taking advantages of its variations in color with light irradiation and also its changes in physical property, such as the refractive index and the permeability, with its changes in phase.

Abstract: A photon mode reaction is caused in an optical recording medium by irradiating the optical recording medium susceptible to the photon mode reaction with light emitted from a light emitting device when driven by a pulsed current.

Abstract: An optical material contains a photochromic compound which is expressed in the following general formula (I): ##STR1## where A represents an oxygen atom, a nitrogen atom, or a substituted nitrogen atom, B represents a thiophene ring, benzothiophene ring, pyrrole ring or indole ring, R.sub.1 represents a methyl group, an alkoxy group or a perfluoroalkyl group, R.sub.2 to R.sub.7 represent a hydrogen atom, a halogen atom, a hydroxy group, an alkyl group and the like respectively. This photochromic compound may be bonded with a polymer as a side chain in the position of A.

Abstract: An optical memory medium having a transparent substrate, a recording layer and a reflective layer, the recording layer and the reflective layer being formed in this order on the transparent substrate. The recording layer is a diarylethene derivative dispersed in a non-polar polymeric binder. The optical memory medium with such a recording layer fully utilizes advantageous properties of the diarylethene derivative, such as good thermal stability of recorded state, excellent durability against repeated color changes between colored and colorless states, and photosensitive property to semiconductor laser light with a wavelength of 780 nm. The optical memory medium enables high-density recording and non-destructive readout.

Abstract: An optical recording medium is provided with a masking layer on a side of a recording layer for receiving a reproducing beam. The masking layer is prepared from that containing photochromic dye molecules having absorption at the wavelength of the reproducing beam and causing a photon mode reaction by absorbing the reproducing beam to be reduced in absorption.

Abstract: A novel benzothiophene/indole-substituted maleimide derivative, a photochromic material and an optical recording material using the same. The benzothiophene/indole-substituted maleimide derivative is represented by the following formula (1): ##STR1## or the following formula (2): ##STR2## wherein R is a substituted or an unsubstituted monovalent hydrocarbon group, R.sup.1 and R.sup.2 are a hydrogen atom, an alkyl group, an alkylthio group or an alkoxy group under the condition where at least either one of them is an alkylthio group or an alkoxy group, R.sup.3 is an alkyl group or an acyl group, and rings A and B may not be substituted or may be substituted with an alkyl group, an alkoxy group or a halogen atom, respectively.

Abstract: Disclosed herein is an optical recording material containing a photochromic compound which is expressed in the following general formula (I): ##STR1## where A represents an oxygen atom or a substituted or unsubstituted nitrogen atom, R.sub.1 represents an alkoxy group, R.sub.2 to R.sub.5 represent substituents such as a hydrogen atom, a halogen atom, a hydroxy group, a substituted or unsubstituted alkyl group and the like respectively, and B represents a substituted or unsubstituted thiophene ring, benzothiophene ring, pyrrole ring or indole ring.

Abstract: The present invention relates to a solution for catalytic treatment, which is effective for applying a catalyst-metal onto the surface of a substrate, which can provide a film having excellent properties such as adhesion, precision and selectivity through electroless plating or the like, and which does not cause a premature and undesirable decomposition in a bath. The solution for catalytic treatment comprises a catalyst-metal in the form of ions, which permits the deposition of the metal serving as a catalyst on a substrate by applying the solution onto the surface of the substrate and then irradiating the substrate with light rays. The present invention also relates to a method of applying a catalyst onto a substrate and a method of forming an electrical conductor in which such a solution for catalytic treatment is employed.

Abstract: A technique for improving a number of reproducible times in reproduction of information from an optical recording medium having a recording layer which reacts in a photon mode. The power of a reproducing beam is set in proximity to P.sub.rep (W) appearing in the following expression (I) or within a range of P.sub.rep (W) appearing in the following expression (II): ##EQU1## In order to improve an S-N ratio, squeezed light having suppressed photon number fluctuation is employed as a reproducing beam at need. If improvement of the number of reproducible times is in preference to improvement of the S-N ratio, such squeezed light having suppressed photon number fluctuation is employed as a reproducing beam with power which is set within a range of P.sub.

Abstract: Disclosed herein is an optical recording medium comprising a recording layer containing a photochromic material and a polymer which are so combined with each other that a photostationary state attained upon irradiation with light of a specific wavelength is varied with temperatures, a reflective layer for reflecting light which is passed through the recording layer, and a substrate for supporting a laminate of the recording layer and the reflective layer.

Abstract: A recording medium comprises a recording layer, a birefringent layer, and a reflecting layer. The recording layer is formed of a material whose optical rotatory power is alterable such that in one state no optical rotatory power is present and, in a second state, optical rotatory power is present. Information is recorded in the recording layer by selectively altering the state of the recording layer. The birefringent layer is formed of a material having constant birefringence without regard to the state of the recording layer. The reflecting layer reflects a light beam transmitted through the recording layer and the birefringent layer to reintroduce the beam into the birefringent layer and the recording layer. A method of reproducing information from this recording medium applies a polarized light beam to the recording medium and detects change of the polarized state of the polarized light beam reflected from the recording medium, thereby reading the information recorded in the recording layer.

Abstract: A novel photochromic compound as a photoreactive material making use of photochromism is provided, which compound is expressed by the following formula (1) or (2)): ##STR1## wherein R is alkyl, alkoxy, perfluoroalkyl or cyano; X.sub.1, X.sub.2, X.sub.3, X.sub.4, X.sub.5 and X.sub.6 are each H, halogen, alkyl, alkoxy, cyano, alkanoyloxy or alkyloxycarbonyl, or a substituted or unsubstituted benzene ring is formed by condensation between at adjacent groups among X.sub.1 to X.sub.6 ; Y is Y.sub.1 C=CY.sub.2, O, S, SO, SO.sub.2 or NY.sub.3 wherein Y.sub.1 and Y.sub.2 are each as defined in the case of the above X.sub.1 to X.sub.6 and Y.sub.3 is H, alkyl, alkanoyl, alkyloxycarbonyl or aryl; and the symbol refers to occurrence of E- or Z-isomer, and which compound is useful as rewritable optical memory element or photo-display element and also as solar energy-storage material, duplicating material, masking material, optical filter, toys, etc.

Abstract: Novel gel compositions are provided which exhibit a drastic discontinuous volume change when exposed to or shielded from light energy.