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: This invention generally relates to a reversible thermosensitive coloring composition and a thermosensitive recording medium using thereof which have high light-resisting characteristics, wherein coloring and decolorizing can be repeated suitably.

Abstract: A reversible thermosensitive coloring recording method for producing multi-color images by use of a reversible thermosensitive coloring recording medium which is composed of a support and a reversible thermosensitive coloring recording layer containing a plurality of reversible thermosensitive coloring compositions, each coloring composition being independently present separated from the other coloring compositions, and capable of reversibly forming a color development state with a different color in a predetermined color development temperature range, and a decolorization state in a predetermined decolorization temperature range by the application of heat thereto and maintaining the above two states at room temperature, the decolorization temperature range being located lower in terms of temperature than the color development temperature range therefor, comprises the steps of: temporarily applying heat to the recording medium to a color development temperature at which at least two of the coloring compositio

Abstract: A reversible thermosensitive coloring recording method for producing multi-color images by use of a reversible thermosensitive coloring recording medium which is composed of a support and a reversible thermosensitive coloring recording layer containing a plurality of reversible thermosensitive coloring compositions, each coloring composition being independently present separated from the other coloring compositions, and capable of reversibly forming a color development state with a different color in a predetermined color development temperature range, and a decolorization state in a predetermined decolorization temperature range by the application of heat thereto and maintaining the above two states at room temperature, the decolorization temperature range being located lower in terms of temperature than the color development temperature range therefor, comprises the steps of: temporarily applying heat to the recording medium to a color development temperature at which at least two of the coloring compositio

Abstract: A reversible thermosensitive coloring recording method for producing multi-color images by use of a reversible thermosensitive coloring recording medium which is composed of a support and a reversible thermosensitive coloring recording layer containing a plurality of reversible thermosensitive coloring compositions, each coloring composition being independently present separated from the other coloring compositions, and capable of reversibly forming a color development state with a different color in a predetermined color development temperature range, and a decolorization state in a predetermined decolorization temperature range by the application of heat thereto and maintaining the above two states at room temperature, the decolorization temperature range being located lower in terms of temperature than the color development temperature range therefor, comprises the steps of: temporarily applying heat to the recording medium to a color development temperature at which at least two of the coloring compositio

Abstract: A reversible thermosensitive coloring composition is composed of an electron-donor coloring compound; an electron-acceptor compound which is capable of producing a colored material with a regularly aggregated structure in the electron-doner coloring compound at a color development initiation temperature to obtain a color development state, and is capable of crystallizing out of the colored material at a decolorization initiation temperature which is lower than the color development initiation temperature; and an organic compound serving as a decolorization-accelerating agent capable of inducing the destruction of the regularly aggregated structure of the colored material to accelerate the decolorization of the composition. A reversible thermosensitive coloring recording medium is composed of a support and a recording layer formed thereon, which contains the above-mentioned reversible thermosensitive coloring composition.

Abstract: A reversible thermosensitive coloring composition is composed of (i) an electron-donor coloring compound and (ii) an electron-acceptor compound selected from the group consisting of an organic phosphoric acid compound, an aliphatic carboxylic acid, and a phenolic compound, each having a straight chain or branched chain alkyl group or alkyenyl group having 12 or more carbon atoms, the electron-donor coloring compound and the electron-acceptor compound being capable of reacting to induce color formation in the reversible thermosensitive coloring composition at the eutectic temperature thereof. The electron-donor coloring compound and the electron-acceptor compound, when fused and colored in a mixed state, with application of heat thereto, followed by rapidly cooling the fused mixture, exhibit an exothermic peak in a temperature elevation process in a differential scanning calorific analysis or in a differential thermal analysis.

Abstract: A reversible thermosensitive coloring composition is composed of (i) an electron-donor coloring compound and (ii) an electron-acceptor compound selected from the group consisting of an organic phosphoric acid compound, an aliphatic carboxylic acid, and a phenolic compound, each having a straight chain or branched chain alkyl group or alkyenyl group having 12 or more carbon atoms, the electron-donor coloring compound and the electron-acceptor compound being capable of reacting to induce color formation in the reversible thermosensitive coloring composition at the eutectic temperature thereof. The electron-donor coloring compound and the electron-acceptor compound, when fused and colored in a mixed state, with application of heat thereto, followed by rapidly cooling the fused mixture, exhibit an exothermic peak in a temperature elevation process in a differential scanning calorific analysis or in a differential thermal analysis.

Abstract: A reversible thermosensitive coloring composition is composed of (i) an electron-donor coloring compound and (ii) an electron-acceptor compound selected from the group consisting of an organic phosphoric acid compound, an aliphatic carboxylic acid, and a phenolic compound, each having a straight chain or branched chain alkyl group or alkenyl group having 12 or more carbon atoms, the electron-donor coloring compound and the electron-acceptor compound being capable of reacting to induce color formation in the reversible thermosensitive coloring composition at the eutectic temperature thereof. The electron-donor coloring compound and the electron-acceptor compound, when fused and colored in a mixed state, with application of heat thereto, followed by rapidly cooling the fused mixture, exhibit an exothermic peak in a temperature elevation process in a differential scanning calorific anlaysis or in a differential thermal analysis.

Abstract: A heat-mode recording medium has (i) a substrate and (ii) a recording layer formed thereon which comprises an organic compound of which crystallization direction can be thermally and reversibly controlled. This heat-mode recording medium can be prepared or initialized by at least the steps of fusing the organic compound contained in the recording layer with application of heat thereto and subsequently cooling a predetermined fused portion of the recording layer in such a fashion that the crystallization direction of the organic compound in the recording layer is oriented in a predetermined direction.

Abstract: The present invention provides a tetrazoneum salt compound represented by the general formula (I): ##STR1## (wherein, X stands for an anion functional group); a disazo compound represented by the general formula (II): ##STR2## wherein, A stands for ##STR3## (wherein, R stands for an alkyl group, an alkoxy group, a nitro group, halogen, a cyano group or a halomethyl group, n stands for an integer of 0, 1, 2 or 3, and in case n is an integer of 2 or 3 R may be the same or different); a method for the production thereof, and electrophotographic elements using the same or like disazo compounds as the charge carrier generating materials.

Abstract: An electrophotographic printing original plate is disclosed, which comprises an electroconductive support material and an electrophotographic photosensitive layer formed thereon, which electrophotographic photosensitive layer comprises (i) a charge generation layer consisting essentially of a particular azo pigment serving as a charge generating material and (ii) a charge transport layer consisting essentially of a charge transporting material and an alkali-soluble resin; and an electrophotographic printing plate making process using the above printing original plate is also disclosed, which comprises the steps of electrically charging uniformly the above printing original plate, exposing the charged printing original plate to optical images to form latent electrostatic images thereon, developing the latent electrostatic images with toner, fixing the toner images to the printing original plate, and removing the electrophotographic photosensitive layer portions corresponding to the non-image areas of the print

Abstract: A plate for use in lithographic printing which comprises providing a photoconductive layer on an electrically conductive substrate and further providing thereon a surface layer (a hydrophilicable layer) consisting essentially of a reaction product of a resin having an acid anhydride group with a crosslinking agent.

Abstract: The present invention provides a tetrazoneum salt compound represented by the general formula (I): ##STR1## (wherein, X stands for an anion functional group.); a disazo compound represented by the general formula (II): ##STR2## (wherein, R stands for an alkyl group, an alkoxy group, a nitro group, halogen, a cyano group or a halomethyl group, n stands for an integer of 0, 1, 2 or 3, and in case n is an integer of 2 or 3 R may be the same or different.); a method for the production thereof, and electrophotographic elements using the same or like disazo compounds as the charge carrier generating materials.

Abstract: An electrophotographic photoconductor comprises an electroconductive supporting material and a photoconductive layer containing a charge carrier producing pigment and a charge transporting material therein, which is formed on the electroconductive supporting material. As the charge carrier producing pigment, azo pigments and other materials which are known as the charge carrier producing pigments are employed. As the charge transporting material, anthracene compounds which are represented by the general formula ##STR1## are employed, wherein X represents H (hydrogen) or a halogen atom and R represents an unsubstituted phenyl radical, a substituted phenyl radial having a halogen substituent, a cyano substituent, a lower dialkyl amino substituent with one to four carbon atoms, a lower alkoxyl substituent with one to five carbon atoms, and nitro substituent, a napthyl radical, an anthryl radical, and a carbazoyl radical.