Abstract: A thin-film EL element having as a laminated luminescent composite a configuration comprising at least a first layer and a second layer wherein(1) the first layer comprises a compound having a lattice constant, before lamination, larger than that of a compound constituting the second layer, and contains manganese as a luminescent center impurity,(2) the difference between the lattice constant, before lamination, of the compound of the first layer and the compound constituting the second layer is 5% or more, and(3) the peak value of the emission spectrum of the laminated luminescent composite rests on 590 nm or more, whereby the thin-film EL element can provide red light having high color purity.

Abstract: An ink ribbon comprising a base film and an ink layer having a thickness of from 1 to 10 .mu.m and containing a particle form infrared ray-emitting fluorescent substance having excellent light emitting characteristics.

Abstract: An ink composition containing an infrared ray-emitting fluorescent substance, at least one dispersant selected from the group consisting of alkylamines and phosphate salts, and a binder resin, which is excellent in light-emitting characteristics.

Abstract: In order to provide a latent image forming member which is capable of surely reading information to have high reliability and which can be used for a long time, the latent image forming member comprises a base (4a), and an information indication layer (2) formed on the base (4a) and having a latent image pattern, in which fluorescent grains are dispersed and held, so that the information indication layer (2) is irradiated with light having a predetermined wavelength to excite the fluorescent grains and luminescent light information from the fluorescent grains is optically read, wherein reflectance of a surface of the base (4a) with respect to light having the predetermined wavelength is 20% or higher, a projection amount T of the information indication layer 2 from the top surface of the base (4a) is restricted to a range of 0.5 to 20 .mu.m, and a protection sheet (6a) is laminated onto the base (4a) as to cover all over the information indication layer (2).

Abstract: An infrared-absorbing mark printed matter in which an infrared-absorbing mark is formed on a substrate by printing with an ink having high light absorptivity in the infrared region; the infrared-absorbing mark is covered up by smearing with an ink having high light absorptivity in the visible region and pervious to light in the infrared region to form a colored concealing layer; and on the colored concealing layer is formed a white concealing layer by printing with an ink containing a white pigment and an extender pigment of which at least part of the particles are those having an average particle size of 3 to 20 .mu.m.

Abstract: A detection mark comprising a pattern formed from a thin phosphor layer which emits a light having a different wavelength from that of an excitation light irradiated on a surface side of the phosphor layer, and an undercoat layer which is formed on a rear surface side of the phosphor layer and reflects the excitation light, which mark can be detected by intermittently irradiating the excitation light to the mark and reading a light or afterglow from the phosphor layer.

Abstract: In a method of charging secondary battery, the charging control is performed when it is detected that the secondary differential value of the detected voltage curve changes from positive value to a negative value at the point C or its near portion.

Abstract: In a dual insulation thin film type electroluminescence device comprising a first insulation layer, a light emitting layer and a second insulation layer between a transparent electrode layer and a back electrode layer, a tantalum oxynitride layer is provided between the transparent electrode layer and the first insulation layer to prevent increase of the resistance in the transparent electrode and to prevent increase of current leakage in the insulation layer so that a high luminescence can be achieved.

Abstract: An electrochromic display device which comprises a display electrode comprising a transparent substrate, a transparent electrode formed on an inner surface of the transparent substrate and an electrochromic material layer for display made of tungstgen oxide and formed on the transparent electrode; a counter electrode comprising a substrate, a conductive layer formed on an inner surface of the substrate and an activated carbon fiber cloth bonded to the conductive layer with a conductive adhesive; and a spacer provided beween the display electrode and the counter electrode with their inner surfaces facing to each other to define, between them, an electrolyte chamber, which is filled with an electrolyte comprising LiClO.sub.4 dissolved in propylene carbonate containing water and an acid, which device has an increased original injected charge and good maintenance of the injected charge after prolonged storage.

Abstract: An electrochromic display device which comprises a display electrode comprising a transparent substrate, a transparent electrode formed on an inner surface of the transparent substrate and an electrochromic material layer for display made of tungsten oxide and formed on the transparent electrode; a counter electrode comprising a substrate, a conductive layer formed on an inner surface of the substrate and an activated carbon fiber material; and a spacer provided between the display electrode and the counter electrode with their inner surfaces facing each other to define, between them, an electrolyte chamber, which is filled with an electrolyte comprising a lithium salt and at least one of the tertiary alkyl ammonium salts and quarternary alkyl ammonium slats dissolved in a non-aqueous medium containing a small amount of water, which device has increased original injected charge which can last for a long time.

Abstract: A magnetic recording medium comprising a substrate, a magnetic layer and a protective layer which consists of an organic polymeric material comprising carbon atoms, hydrogen atoms and oxygen atoms, the content of the oxygen atoms increasing towards the outer surface of the protective layer, which has improved durability and corrosion resistance.