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.

Abstract: The present invention is intended to provide a metal scavenger that is free from the defects of metal scavengers formed by introducing dithioic acid groups to polyalkylenepolyamines or the like, is high in settling speed of flock when used in waste water treatment, and can carry out treatment of waste water efficiently and also to provide a process of producing the same efficiently. The present metal scavenger has a structure that is formed by replacing the hydrogen atoms linked to the nitrogen atoms of a polyamine having aminomethyl groups by dithioic acid groups or their salts and that is represented by the following general formula: ##STR1## wherein R represents a dithioic acid group, an alkali metal dithioate group, an alkaline earth metal dithioate group, or an ammonium dithioate group and R' represents a hydrogen atom, a dithioic acid group, an alkali metal dithioate group, an alkaline earth metal dithioate group, or an ammonium dithioate group.

Abstract: Metal scavengers suitable for use in the treatment of waste water are disclosed. The metal scavengers individually comprise a polyamine derivative and a polyethyleneimine derivative. The polyamine derivative is formed of a polyamine having a molecular weight not higher than 500 and contains, per molecule of the polyamine, at least one dithiocarboxyl group or a salt thereof as an N-substituting group substituted for an active hydrogen atom of the polyamine such that at least 30% of suitable active hydrogen atoms contained in the polyamine are substituted by the dithiocarboxyl group or salt thereof.

Abstract: A process for the treatment of contaminants using metal scavenger is disclosed. The metal scavengers individually comprise a polyamine derivative and a polyethyleneimine derivative. The polyamine derivative is formed of a polyamine having a molecular weight not higher than 500 and contains, per molecule of the polyamine, at least one dithiocarboxyl group or a salt thereof as an N-substituting group substituted for an active hydrogen atom of the polyamine. The polyethyleneimine derivative is formed from a polyethyleneimine having an average molecular weight of at least 5,000 and contains, per molecule of the polyethyleneimine, at least one dithiocarboxyl group or a salt thereof as an N-substituting group substituted for an active hydrogen atom of the polyethyleneimine.

Abstract: A heavy metal can be removed from waste water, in which the metal is contained as ions, by adding to the waste water a metal scavenger together with at least one of sodium monosulfide, sodium polysulfides and sodium hydrogensulfide to form a metal ion containing floc. The resulting floc is then removed from the waste water by filtration. The metal scavenger contains at least one carbodithio group and/or at least one carbodithioate salt group as N-substituents per molecule.

Abstract: A metal scavenger is composed of an addition product of a polyamine and an epihalohydrin. The addition product contains as substituent or substituents at least one carbodithio group and/or at least one carbodithioate salt group introduced therein by substituting the corresponding number of active hydrogen atom or atoms in the addition product. Metals can be scavenged from waste water by adding the metal scavenger together with at least one of sodium monosulfide, sodium polysulfides and sodium hydrogensulfide.

Abstract: A metal scavenger is composed of an addition product of a polyamine and an epihalohydrin. The addition product contains as substituent or substituents at least one carbodithio group and/or at least one carbodithioate salt group introduced therein by substituting the corresponding number of active hydrogen atom or atoms in the addition product. Metals can be scavenged from waste water by adding the metal scavenger together with at least one of sodium monosulfide, sodium polysulfides and sodium hydrogensulfide.

Abstract: A process for producing a spherical chelating resin is disclosed. In the production, a prepolymer is prepared in the absence or presence of a solvent by subjecting a poly-N-substituted polyamine having at least two residual active hydrogen atoms bonded to nitrogen atoms or a poly-N-substituted polyalkylene imine having at least two residual active hydrogen atoms bonded to nitrogen atoms to a poly-addition reaction with an epoxy compound having at least two epoxy groups. The prepolymer is cured by heating and agitating a suspension of the prepolymer in an aqueous solution of a water-soluble high polymer or a nonionic surfactant in the absence or presence of known curing agents for epoxy resins. The resulting spherical cured resin is subjected to a saponification reaction or to a reaction with a hydrazine or a polyamine, and then a spherical chelating resin is obtained.

Abstract: Polyaddition polymers comprising the reaction products of bis-epoxy compounds with poly-N-substituted polyamines or poly-N-substituted polyalkylene imines, wherein said poly-N-substituted polyamines and said polyalkylene imines contain at least two active hydrogens, and which polyamines and polyalkylene imines contain alkali metal salts or alkyl ester groups of carboxyalkyl groups or cyanoalkyl groups which are substituents on the nitrogen atoms of said polyamines of polyalkylene imines. The polymer is extremely useful for chelating and recovering heavy metal ions from industrial waste liquids and also effective as adhesives, resin for paint, electrostatic inhibitor for polymer, electro-conductive polymer, rust inhibitor ion-exchanging material and the like. The polymer may be obtained in the form of particles of a controlled particle size.