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: A reversible thermal recording method using a color/non-color type reversible thermosensitive recording material which has a recording layer formed overlying at least one side of a substrate and including an electron donating coloring agent and an electron accepting color developer and which reversibly forms a colored state and a non-colored state by being appropriately heated and cooled. The recording layer having images of the colored state which have been formed in the recording layer is heated to erase the image, and imagewise heated either at substantially the same time as, or after, the image erasing operation to record new images therein, and then relatively rapidly cooled to maintain the new images. A reversible thermal recording apparatus therefor is also provided.

Abstract: A reversible thermosensitive recording material which includes a recording layer including an electron donating coloring agent and an electron accepting coloring developer and in which an image is reversibly formed and erased by appropriately heating and cooling the recording layer, wherein the recording material has an image density retention not less than about 60% when the recording material having an image is allowed to settle in a dry place at 50.degree. C. for 24 hours, a residual image density not greater than about 0.03 when the recording material having an image is heated at 110.degree. C. for 0.5 seconds to erase the image, and a residual image density after light irradiation not greater than about 0.04 when the recording material having an image is heated at 110.degree. C. for 0.5 seconds to erase the image after light of 5,000 lux is irradiated to the recording material for 100 hours.

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 coloring composition is provided, which contains (a) an electron-donating coloring compound; and (b) an electron-accepting compound, which is an aromatic carboxylic acid compound comprising at least one hydrocarbon group, which induces color formation in the electron-donating coloring compound. The reversible thermosensitive coloring composition reversibly assumes a color-developed state or a decolorized state, in response to at least one of (1) the temperature thereof when heated and (2) the cooling rate of the reversible thermosensitive coloring composition when cooled after the heating thereof. A reversible thermosensitive recording medium using the coloring composition is also provided.

Abstract: A reversible thermosensitive coloring composition contains an electron-donating coloring compound and an electron-accepting compound, and is capable of reversibly assuming a color-developed state or a decolorized state depending upon the the temperature of the reversible thermosensitive coloring composition when heated, and/or the cooling rate of the reversible thermosensitive coloring composition when cooled after the heating thereof, with the electron-accepting compound being a compound of formula (I):A--R--X (I)wherein A represents a color-developing moiety; R represents an aliphatic hydrocarbon group comprising as the main chain thereof a straight chain hydrocarbon group having 8 or more carbon atoms, and may comprise a bivalent hetero-atom containing group and/or a bivalent aromatic group; and X represents a hetero-atom containing associative group.

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 coloring composition is provided, which contains (a) an electron-donating coloring compound; and (b) an electron-accepting compound, which is an aromatic carboxylic acid compound comprising at least one hydrocarbon group, which induces color formation in the electron-donating coloring compound. The reversible thermosensitive coloring composition reversibly assumes a color-developed state or a decolorized state, in response to at least one of (1) the temperature thereof when heated and (2) the cooling rate of the reversible thermosensitive coloring composition when cooled after the heating thereof. A reversible thermosensitive recording medium using the coloring composition is also provided.

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.

Abstract: A reversible thermosensitive coloring composition contains an electron-donating coloring compound and an electron-accepting compound, and is capable of reversibly assuming a color-developed state or a decolorized state depending upon the the temperature of the reversible thermosensitive coloring composition when heated, and/or the cooling rate of the reversible thermosensitive coloring composition when cooled after the heating thereof, with the electron-accepting compound being a compound of formula (I):A-R-X (I)wherein A represents a color-developing moiety; R represents an aliphatic hydrocarbon group comprising as the main chain thereof a straight chain hydrocarbon group having 8 or more carbon atoms, and may comprise a bivalent hetero-atom containing group and/or a bivalent aromatic group; and X represents a hetero-atom containing associative group.

Abstract: A thermosensitive coloring composition is disclosed which includes a coloring agent and a color developer of the formula: ##STR1## wherein R.sup.1 represents hydrogen, a halogen, a hydroxyl group, an alkyl group or an alkoxy group, R.sup.2 represents a C.sub.1-8 aliphatic hydrocarbon group, A represents a divalent aliphatic hydrocarbon group, B represents a substituted or non-substituted aromatic or aliphatic divalent group, Y and Z each represent a hetero atom-containing divalent group, n is an integer of 1-3 and p and q are each an integer of 0 or 1. A reversible thermosensitive recording medium includes a support and a thermosensitive layer of the above coloring composition formed thereon.

Abstract: A recording material contains at least two coordination compounds which react to produce at least one newly produced coordination compound with the occurrence of visual changes in the recording material, which visual changes are utilized for recording.

Abstract: A thermosensitive recording material capable of being imagewise colored when heated, having a support, and a thermosensitive recording layer formed thereon which contains an N-substituted indole or an aromatic polyhydroxy compound, a carbonyl compound, and an acid material.

Abstract: A thermosensitive recording material composed of a support, and a thermosensitive recording layer formed on the support, containing a leuco dye, a color developer capable of inducing color formation in the leuco dye upon application of heat thereto, and a thermofusible material including p'-methylphenyl p-chlorobenzoate serving as a thermosensitivity-improving agent.