Abstract: A heat-sensitive color-developing composition containing a hydroxyquinoline compound having a methyl group and an acid anhydride compound represented by general formula (1): wherein ring A represents a substituted or unsubstituted aromatic hydrocarbon ring, and n represents an integer of 1 to 3, and a heat-sensitive recording material containing the composition in a recording layer.

Abstract: [Problem to be Solved] To provide a heat-sensitive recording material having high fastness and a vivid hue. [Solution] A heat-sensitive color-developing composition containing a hydroxyquinoline compound having a methyl group and an acid anhydride compound represented by general formula (1): wherein ring A represents a substituted or unsubstituted aromatic hydrocarbon ring, and n represents an integer of 1 to 3, and a heat-sensitive recording material containing the composition in a recording layer.

Abstract: A novel optical recording medium having at least a recording layer and a reflective layer on a substrate is herein disclosed, wherein at least one dipyrromethene metal chelate compound represented by formula (1) is contained in the recording layer: wherein R1 and R9 are each independently an alkenyl group, an aryl group or a heteroaryl group; R2 to R8 are each independently a hydrogen atom, a halogen atom, or a substituted or unsubstituted alkyl, alkoxy, alkenyl, acyl, alkoxycarbonyl, aralkyl, aryl or heteroaryl group having 20 or less carbon atoms; and M is a transition metal.

Abstract: A novel optical recording medium having at least a recording layer and a reflective layer on a substrate is herein disclosed, wherein at least one dipyrromethene metal chelate compound represented by formula (1) is contained in the recording layer: ##STR1## wherein R.sub.1 and R.sub.9 are each independently an alkenyl group, an aryl group or a heteroaryl group; R.sub.2 to R.sub.8 are each independently a hydrogen atom, a halogen atom, or a substituted or unsubstituted alkyl, alkoxy, alkenyl, acyl, alkoxycarbonyl, aralkyl, aryl or heteroaryl group having 20 or less carbon atoms; and M is a transition metal.

Abstract: The invention relates to novel phthalocyanine compounds, their intermediates and a process for their preparation. The inventive phthalocyanine compound absorbs in the near infrared region of the spectrum with a high absorption coefficient which features high solubility in solvents, good compatibility with resins and high aging resistance, thus finding application as a near infrared ray absorbing material or a light-heat conversion material with great advantage and to a process for producing the phthalocyanine compound. The novel phthalocyanine compound has the following general formula: ##STR1## wherein R represents alkyl or alkoxyalkyl; X represents halogen, alkylthio, phenylthio which may be substituted, or naphthylthio which may be substituted; M represents a couple of hydrogen atoms, a divalent metal, or a trivalent or tetravalent metal derivative. The near infrared ray absorbing and light-heat conversion materials containing the above phthalocyanine compound are also described.

Abstract: The invention relates to a novel phthalocyanine compound absorbing in the near infrared region of the spectrum with a high absorption coefficient which features high solubility in solvents, good compatibility with resins and high aging resistance, thus finding application as a near infrared ray absorbing material or a light-heat conversion material with great advantage and to a process for producing the phthalocyanine compound. The novel phthalocyanine compound has the following general formula: ##STR1## wherein R represents alkyl or alkoxyalkyl; X represents halogen, alkylthio, phenylthio which may be substituted, or naphthylthio which may be substituted; M represents a couple of hydrogen atoms, a divalent metal, or a trivalent or tetravalent metal derivative. The near infrared ray absorbing and light-heat conversion materials containing the above phthalocyanine compound are also described.

Abstract: A phthalide compound of general formula (I) and a near infrared absorber and a recording material each utilizing the phthalide compound are disclosed. ##STR1## wherein ring A represents a substituent group of the following formula ##STR2## where the other substituents are as defined in the disclosure. The near infrared absorber and the recorded image on the recording material absorb strongly the near infrared region with no appreciable absorption in the visible region of the spectrum. The near infrared absorber is colorless or pale in color and yet highly capable of absorbing near infrared radiation. The recorded image on the recording material can hardly be read with the eye but can be read with the OCR. Moreover, the effect on the developed shade of any concomitant color former in a recording material is minimal.

Abstract: There is here disclosed a method for preparing an alkoxyphthalocyanine represented by the formula (1): ##STR1## wherein each of Rs is independently a secondary alkyl group having 3 to 20 carbon atoms, Met is a divalent metal atom or an oxy metal, and the substitution positions of -ORs are the 1- or 4-position, the 5- or 8-position, the 9- or 12 position, and the 13- or 16-position, which comprises the steps of heating a mixture of 3-alkoxyphthalonitrile and an organic base in an alcohol to 90.degree.-120.degree. C., adding a metal derivative at the same temperature, and then carrying out reaction, or alternatively the step of reacting a mixture of a 1,3-diimino-4-alkoxyisoindoline and a metal derivative in the presence or absence of an organic base in an aliphatic alcohol having 6 or more carbon atoms. In addition, the ratio of isomers of the alkoxyphthalocyanine can be controlled by regulating the addition time of the organic base.

Abstract: There is here disclosed a method for preparing an alkoxyphthalocyanine represented by the formula (1): ##STR1##