Abstract: A process for decomposing a thermoplastic polymer composition which comprises a polyhydroxycarboxylic acid base polymer as a primary component in an alkaline solution, recovering hydroxycarboxylic acid from the solution by electrodialysis or acid-precipitation and using the recovered hydroxycarboxylic acid for a polymer material, when desired, is provided.

Abstract: Near-infrared absorbers which contain phthalocyanine derivatives in which the four benzene rings contained in the molecule independently have 1 to 4 substituents are light and thermal resistant and possess high molar extinction coefficients. Such near-infrared absorbers are useful in optical recording media, near-infrared absorption filters, and liquid crystal display devices.

Abstract: A multilayer composite consisting of aluminum and a resin composition primarily comprising a lactic acid base polymer, is disclosed. The composite material is excellent in mechanical and gas barrier properties and has characteristic of totally decomposing under alkaline conditions.

Abstract: The invention discloses a CD-WO type optical recording medium which has a constitution obtained by successively laminating a recording layer, a metal reflection layer and a protective layer; is prepared by using in the recording layer a colorant having a melting point of 150.degree. to 300.degree. C., decomposition initiating temperature of 200.degree. to 350.degree. C., and .lambda. max of 720 nm; and has high sensitivity, low recording distortion and high durability. The colorant can be enhanced its effect by introducing halogen atoms.

Abstract: Foams comprising innumerable cells dispersed in thermoplastic polymer compositions substantially consisting of polylactic acid or a copolymer of lactic acid and hydroxycarboxylic acid and having degradable characteristics in the natural environment.The foams can be used for containers such as food trays and throw away cups comprising molded sheet foam of a thermoplastic and degradable polymer or heat insulating materials and cushioning materials comprising bulk foam.

Abstract: Near-infrared absorbers which contain phthalocyanine derivatives in which the four benzene rings contained in the molecule independently have 1 to 4 substituents are light and thermal resistant and possess high molar extinction coefficients. Such near-infrared absorbers are useful in optical recording media, near-infrared absorption filters, and liquid crystal display devices.

Abstract: A degradable polymer composition essentially consisting of a mixture of a thermoplastic polymer composition primarily comprising polylactic acid or lactic acid-hydroxycarboxylic acid copolymer and one or more substance selected from starch and modified starch, and is a degradable polymer which does not cause problems such as environmental pollution and can be used for films, filaments and packaging materials, food packaging materials in particular.

Abstract: A laminate comprising a thermoplastic polymer essentially consisting of polylactic acid, a copolymer of lactic acid and hydroxycarboxylic acid or a mixture of polylactic acid with a copolymer of lactic acid and hydroxycarboxylic acid, and a regenerated cellulose film, paper, leather, cloth, or fiber. The laminate undergoes degradability in the natural environment, is excellent in transparency, gloss and moisture-proofness, has high strength and can be used for various packaging materials.

Abstract: .alpha.-L-Aspartyl-L-phenylalanine methyl ester (.alpha.-APM) is prepared by catalytic hydrogenation of N-benzyloxycarbonyl-.alpha.-L-aspartyl-L-phenylalanine methyl ester (Z-.alpha.-APM). The catalytic hydrogenation is conducted in an aqueous suspension containing the Z-.alpha.-APM in the form of particles whose average particle size is not greater than 800 .mu.m. The starting Z-.alpha.-APM may contain up to 30 wt. % of its .beta.-isomer provided that the process additionally includes recrystallization of the .alpha.-APM, collection of the .alpha.-APM by filtration and recycling of the filtrate for use in the aqueous suspension of Z-.alpha.-APM.

Abstract: Near infrared absorbers which have a molecular extinction coefficient of 200,000 or more and are represented by the formula (I) ##STR1## wherein each of Y.sup.1, Y.sup.2, Y.sup.3, Y.sup.4, Y.sup.5, Y.sup.6, Y.sup.7 and Y.sup.8 is hydrogen, an alkyl group, alkoxyl group or alkylthio group; each of A.sup.1, A.sup.2, A.sup.3, A.sup.4, A.sup.5, A.sup.6, A.sup.7 and A.sup.8 is hydrogen, halogen, a nitro group, alkyl group, aralkyl group, alkenyl group, alkynyl group, alkoxyl group, aryloxy group, alkylthio group or arylthio group; and Met represents two hydrogen atoms or a metal, are useful for the production of optical display and recording materials.

Abstract: A process for preparing polyhydroxycarboxylic acid by conducting a dehydration condensation of a hydroxycarboxylic acid or an oligomer thereof in a reaction mixture containing an organic solvent substantially in the absence of water and the polyhydroxycarboxylic acid thus obtained. The process provides polyhydroxycarboxylic acid having excellent properties and processability.

Abstract: Near infrared absorbers which have a molecular extinction coefficient of 200,000 or more and are represented by the formula (I) ##STR1## wherein each of Y.sup.1, Y.sup.2, Y.sup.3, Y.sup.4, Y.sup.5, Y.sup.6, Y.sup.7 and Y.sup.8 is hydrogen, an alkyl group, alkoxyl group or alkylthio group; each of A.sup.1, A.sup.2, A.sup.3, A.sup.4, A.sup.5, A.sup.6, A.sup.7 and A.sup.8 is hydrogen, halogen, a nitro group, alkyl group, aralkyl group, alkenyl group, alkynyl group, alkoxyl group, aryloxy group, alkylthio group or arylthio group; and Met represents two hydrogen atoms or a metal, are useful for the production of optical display and recording materials.

Abstract: A method for preparing a halogenated alkoxyphthalocyanine represented by the formula (7) ##STR1## wherein R.sup.3 to R.sup.6 may be different and each of them is a secondary alkyl group, X is a halogen atom, n is the number of X and in the range of from 1 to 4, and Met is two hydrogen atoms, a divalent metal atom, or a trivalent or a tetravalent metallic derivative, which comprises the step of reacting a metal or a metallic compound with one to four kinds of raw materials selected from the group consisting of phthalonitriles represented by the following formula (1) and diiminoisoindolines represented by the following formula (2) ##STR2## wherein R.sup.1 is a secondary alkyl group, X is a halogen atom, and each of p and q is 0 or 1, but in at least one raw material, p or q is 1, and halogenated alkoxyphthalocyanine prepared by said method.

Abstract: A hydrazone compound represented by the following formula (I): ##STR1## wherein R.sub.1 and R.sub.2 each are an aryl group or collectively with the carbon to which they are attached form a polycyclic group; R.sub.3 represents a hydrogen or halogen atom or an alkyl or phenyl group; and R.sub.4 and R.sub.5 each represent an alkyl, aralkyl or aryl group, with the proviso that at least one of R.sub.4 and R.sub.5 is an aryl group, is useful as a charge-transporting material in an electrophotographic photoreceptor and are produced by condensing the corresponding aldehyde with the corresponding H.sub.2 N--NR.sub.4 R.sub.5 hydrazine.

Abstract: A hydrazone compound represented by the following formula (I): ##STR1## wherein R.sub.1 and R.sub.2 each are an aryl group or collectively with the carbon to which they are attached form a polycyclic group; R.sub.3 represents a hydrogen or halogen atom or an alkyl or phenyl group; and R.sub.4 and R.sub.5 each represent an alkyl, aralkyl or aryl group, with the proviso that at least one of R.sub.4 and R.sub.5 is an aryl group, is useful as a charge-transporting material in an electrophotographic photoreceptor and are produced by condensing the corresponding aldehyde with the corresponding H.sub.2 N--NR.sub.4 R.sub.5 hydrazine.

Abstract: Near infrared absorbers which have a molecular extinction coefficient of 200,000 or more and are represented by the formula (I) ##STR1## wherein each of Y.sup.1, Y.sup.2, Y.sup.3, Y.sup.4, Y.sup.5, Y.sup.6, Y.sup.7 and Y.sup.8 is hydrogen, an alkyl group, alkoxyl group or alkylthio group; each of A.sup.1, A.sup.2, A.sup.3, A.sup.4, A.sup.5, A.sup.6, A.sup.7 and A.sup.8 is hydrogen, halogen, a nitro group, alkyl group, aralkyl group, alkenyl group, alkynyl group, alkoxyl group, aryloxy group, alkylthio group or arylthio group; and Met represents two hydrogen atoms or a metal, are useful for the production of optical display and recording materials.

Abstract: Near-infrared absorbers which contain phthalocyanine derivatives in which the four benzene rings contained in the molecule independently have 1 to 4 substituents are light and thermal resistant and possess high molar extinction coefficients. Such near-infrared absorbers are useful in optical recording media, near-infrared absorption filters, and liquid crystal display devices.

Abstract: Phthalocyanine compounds are described, which are represented by the following general formula (I): ##STR1## wherein R.sub.1 -R.sub.8 are individually a hydrogen atom or an alkyl or aryl group, a-h stand individually for an integer of 1-20, and M denotes two hydrogen atoms or a metal atom, metal halide, metal oxide, metal hydroxide, dialkylmetal, diarylmetal, bis(alkyloxy)metal or bis(trialkylsilyloxy)metal. Optical recording media and liquid crystal display panels, which contain at least one of the phthalocyanine compounds, are also described.

Abstract: Disclosed are near-infrared absorbents comprising 1,2-naphthalocyanine derivatives wherein the four naphthalene rings contained in the molecule independently have 1 to 6 substituents. Also disclosed is the use of these near-infrared absorbents in optical recording media, near-infrared absorption filters and display materials.