Abstract: The thermo reversible recording medium comprises a substrate and a thermo sensible layer. This thermo sensible layer is made of resin and organic lower molecular weight substance and can become transparent-state or opaque-state depending on temperature. The organic lower molecular weight substance is a linear hydrocarbon-containing compound having no carboxyl group (A) and a linear hydrocarbon-containing compound having no carboxyl group (B) having a melting point lower than the melting point of the linear hydrocarbon-containing compound having no carboxyl group (A) by 20° C. or more.

Abstract: A reversible thermosensitive recording medium includes a reversible thermosensitive recording layer including a matrix resin and an organic low-molecular-weight material dispersed in the matrix resin, of which transparency is reversibly changeable depending upon the temperature thereof, and having (1) a transparentizing upper-limit temperature of 125° C. or more, (2) a temperature difference of 20° C. or less between said transparentizing upper-limit temperature and an opaqueness initiation lower-limit temperature, and (3) a transparentizing initiation temperature of less than 95° C., and a method of recording and erasing images, using the recording medium, a method of producing the recording medium, and the application thereof a card, a label, writable or rewritable disk cartridge, disk and tape cassette are proposed.

Abstract: The thermo reversible recording medium comprises a substrate and a heat sensible layer. This heat sensible layer is made of resin and organic lower molecular weight substance and can becoming transparent or non-transparent or vice versa depending on temperature. The organic lower molecular weight substance is a linear hydrocarbon-containing compound having no carboxyl group (A) and a linear hydrocarbon-containing compound having no carboxyl group (B) having a melting point lower than the melting point of the linear hydrocarbon-containing compound having no carboxyl group (A) by 20° C. or more.

Abstract: A reversible thermosensitive recording medium is capable of assuming a first color in a first temperature range which is above room temperature, having a first color assuming initiation temperature and a first color assuming upper-limit temperature, and assuming a second color when heated to a second temperature range which is above the first temperature range and then cooled, having a second color assuming lower-limit temperature, (a) the first color assuming upper-limit temperature being 125° C. or more, (b) the difference between the first color assuming upper-limit temperature and the second color assuming lower-limit temperature being 20° C. or less, and (c) the first color assuming initiation temperature being 95° C. or more, and a method of recording and erasing images, using the recording medium, a method of producing the recording medium, and the application thereof a card, a label, writable or rewritable disk cartridge, disk and tape cassette are proposed.

Abstract: A reversible thermosensitive recording medium includes a reversible thermosensitive recording layer including a matrix resin and an organic low-molecular-weight material dispersed in the matrix resin, of which transparency is reversibly changeable depending upon the temperature thereof, and having (1) a transparentizing upper-limit temperature of 125° C. or more, (2) a temperature difference of 20° C. or less between said transparentizing upper-limit temperature and an opaqueness initiation lower-limit temperature, and (3) a transparentizing initiation temperature of less than 95° C., and a method of recording and erasing images, using the recording medium, a method of producing the recording medium, and the application thereof a card, a label, writable or rewritable disk cartridge, disk and tape cassette are proposed.

Abstract: Disclosed herein are a solid waste treatment agent comprising phosphorous acid or a derivative thereof and/or hypophosphorous acid or a derivative thereof, or phosphorous acid or a derivative thereof and/or hypophosphorous acid or a derivative thereof, and an aluminum compound and/or a titanium compound, and a method of treating solid waste, which comprises adding the solid waste treatment agent to solid waste containing harmful metals and/or organic chlorinated compounds such as dioxins and PCB to make the solid waste harmless.

Abstract: A reversible thermosensitive composition including a coloring agent and a developer and capable of assuming a colored state and a discolored state depending upon the thermal hysteresis thereof. The developer is a phenol compound represented by the formula: ##STR1## wherein n is an integer of between 1 and 3, X represents a divalent group having a nitrogen atom or an oxygen atom, R.sup.1 represents a substituted or non-substituted aliphatic hydrocarbon group having at least two carbon atoms and R.sup.2 represents a hydrocarbon group. A reversible thermosensitive recording medium has a thermosensitive recording layer containing the above composition.

Abstract: A reversible thermosensitive composition including a coloring agent and a developer and capable of assuming a colored state and a discolored state depending upon the thermal hysteresis thereof. The developer is a phenol compound represented by the formula: ##STR1## wherein R.sup.1 and R.sup.3 represent, independently from each other, a substituted or non-substituted hydrocarbon group, R.sup.2 represents a substituted or non-substituted aliphatic hydrocarbon group having at least two carbon atoms, with the proviso that the total number of carbon atoms of R.sup.1, R.sup.2 and R.sup.3 is at least 8, X and Y represent, independently from each other, a divalent group having a nitrogen atom or an oxygen atom and r is an integer of between 1 and 3.

Abstract: A reversible thermosensitive composition including a coloring agent and a developer and capable of assuming a colored state and a discolored state depending upon the thermal hysteresis thereof. The developer is a phenol compound represented by the formula: ##STR1## wherein R.sup.1 represents a substituted or non-substituted divalent hydrocarbon group having at least two carbon atoms, R.sup.2 represents a substituted or non-substituted hydrocarbon group, X and Y represent, independently from each other, a divalent group having a hetero atom and r is an integer of between 1 and 3. A reversible thermosensitive recording medium includes a support and a thermosensitive layer including the above composition.

Abstract: A reversible thermosensitive medium having a support and a thermosensitive layer, the layer comprising a composition including a coloring agent and a developer and capable of assuming a colored state and a discolored state depending upon the thermal hysteresis thereof. The developer is a phenol compound represented by the formula: ##STR1## wherein n is an integer of between 1 and 3, X represents a divalent group having a nitrogen atom or an oxygen atom, R.sup.1 represents a substituted or non-substituted aliphatic hydrocarbon group having at least two carbon atoms and R.sup.2 represents a hydrocarbon group. A reversible thermosensitive recording medium has a thermosensitive recording layer containing the above composition.

Abstract: A thermally reversible color forming composition which includes an electron-donating chromophoric compound and an electron-accepting compound, by which formation and deletion of a color image may be carried out by adjusting thermal energy applied to the composition, wherein the electron-accepting compound is a carboxylic acid compound having the following general formula (1):R.sub.1 --X--R.sub.2 --COOH (1)in which, X represents a divalent group having at least one hetero atom, R.sub.1 represents a hydrocarbon group having at least one hetero atom, R.sub.2 represents an aliphatic hydrocarbon group, which may be substituted and whose principle chain contains less than 6 carbon atoms.