Abstract: The present invention provides a resin composition comprising polylactic acid and aliphatic polyester carbonate, which has practically adequate heal-resistance temperature, moldability, thermostability, solvent resistance and high mechanical strength, as well as a molded article thereof. In the resin composition, the Vicat softening point is 60° C. or more, the tensile modulus of elasticity is 0.9 GPa or more, the modulus in flexure is 0.6 GPa or more, and the mixing ratio of polylactic acid (A) and aliphatic polyester carbonate (B), in terms of the ratio of (A)/(B) by weight, is 95/5 to 5/95.

Abstract: The present invention provides a resin composition comprising polylactic acid and aliphatic polyester carbonate, which has practically adequate heat-resistance temperature, moldability, thermostability, solvent resistance and high mechanical strength, as well as a molded article thereof. In the resin composition, the Vicat softening point is 60° C. or more, the tensile modulus of elasticity is 0.9 GPa or more, the modulus in flexure is 0.6 GPa or more, and the mixing ratio of polylactic acid (A) and aliphatic polyester carbonate (B), in terms of the ratio of (A)/(B) by weight, is 95/5 to 5/95. Further, the present invention provides a biodegradable injection-molded article having improvements in mechanical characteristics and impact resistance and superior disposal properties, particularly having strength enough to make it usable as a headgear material for use in helmets.

Abstract: A resin molded article having a moveable projecting portion suitable for use in forming a keyboard or keyboard switch and which is substantially free from flex fatigue. At least the moveable projecting portion of the molded article is formed from a resin composition containing a polyether ester block copolymer and a small amount of an alkali metal salt of an aliphatic carboxylic acid having 10 to 36 carbon atoms. The polyether ester block copolymer contains units from terephthalic acid, tetramethylene glycol and polyoxytetramethylene glycol. The resin molded article includes a thick projecting (moveable) portion, a base portion and a flexible thin side portion connecting the thick projecting portion to the base portion. The side portion has a thickness of 0.05 to 0.5 mm and a flexibility retention of at least 85%.

Abstract: An electrical or electronic part having excellent resistance to moist heat, such as a coil bobbin, a condenser case, an IC carrier, a plug, a socket or a fuse case, formed from a polybutylene naphthalenedicarboxylate resin as a raw material; and a flame-retardant resin composition and an electrical part therefrom are also provided. The flame-retardant resin composition exhibits high fluidity and forms little burr, and the electrical part has excellent flame retardancy and well-balanced properties.

Abstract: A polyester resin composition;(A) which contains(a) a thermoplastic polyester resin, and(b) a carbon black and/or a graphite, and(B) in which the content of the above component (b) is 0.001 to 2% by weight based on the total weight of the components (a) and (b). The polyester resin composition may further contain (c) a bromine-containing flame retardant, (d) an antimony-containing flame retardant aid and (e) an inorganic filler in addition to the components (a) and (b). This polyester resin composition permits marking of fine lines and precise print with a high contrast with a laser light.

Abstract: A flame-retardant resin composition comprising (A) polybutylene terephthalate, a copolymer comprising at least 60.0% by weight of butylene terephthalate units and/or a thermoplastic polyester blend comprising at least 60.0% by weight of polybutylene terephthalate, (B) a brominated epoxy resin type flame retardant and/or a brominated polycarbonate type flame retardant, (C) a flame retardant assistant composed mainly of antimony trioxide and/or antimony pentoxide, (D) a hydrous basic carbonate compound of magnesium and aluminum, and (E) optionally an inorganic filler.This resin composition has an excellent flame retardancy, balanced performances, and an improved molding processability (flowability, molding cycle, mold-staining resistance and the like), and a staining of metals or a formation of decomposition products and volatile substances is controlled when the composition is used for molding electrical parts.

Abstract: A thermally stable extrusion-molded article characterized by (1) consisting of a substantially linear polyester in which at least 90 mol% of the total recurring units consist of tetramethylene 2,6-naphthalate units, (2) having a density not in excess of 1.318, and (3) being in the unstretched state.This article is prepared by extruding a melt of a substantially linear polyester in which at least 90 mol% of the total recurring units consist of tetramethylene 2,6-naphthalate units into the form of a molded structure, and cooling the extruded molded structure to room temperature, wherein during the period in which the extruded molded structure is cooled from at least 75%C. to room temperature, the cooling of the molded structure is performed rapidly so that the density of the molded structure does not exceed 1.318.

Abstract: A process for preparing a shaped article by melt-extruding a polyester containing tetramethylene naphthalene-2,6-dicarboxylate or hexamethylene naphthalene-2,6-dicarboxylate as a main recurring unit, wherein the extrudate is exposed to a temperature of 75.degree. to 450.degree.C. for 1 to 180 seconds immediately after extrusion.

Abstract: An electrically insulating material composed of an unstretched film of a substantially linear polyester at least 85 mol% of the recurring units of which consist of a hexamethylene naphthalene-2,6-dicarboxylate unit and which has an intrinsic viscosity, as measured on its ortho-chlorophenol solution at 35.degree.C., of at least 0.3.

Abstract: A biaxially oriented polyethylene-2,6-naphthalate film, which comprises a blended mixture of1. a polyethylene-2,6-naphthalate resin which may contain a unit derived from not more than 10mol% of a polyester-forming component other than a polyethylene-2,6-naphthalate-forming component, and2. 0.5 to 10% by weight, based on the polyethylene-2,6-naphthalate resin (1), of a polyester resin other than the polyethylene-2,6-naphthalate resin (1) in which the amount of the homopolyester unit is at least 90 mol%,Said film having a softing point at least 1.degree.C. higher than the its equilibrium softening point, and a process for its production.