Polylactic acid resin foamed molding and process for manufacturing the same

• Main Authors: NAITO MASATO, OKUDA MASAYASU, TAKASE KENICHI
• Format: Patent
• Language: English
• Published: 01.06.2010
• Subjects: ACCESSORIES, CLOSURES, OR FITTINGS THEREFOR; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F,C08G; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING; CHEMISTRY; COMPOSITIONS BASED THEREON; CONTAINERS FOR STORAGE OR TRANSPORT OF ARTICLES OR MATERIALS,e.g. BAGS, BARRELS, BOTTLES, BOXES, CANS, CARTONS, CRATES,DRUMS, JARS, TANKS, HOPPERS, FORWARDING CONTAINERS; CONVEYING; GENERAL PROCESSES OF COMPOUNDING; HANDLING THIN OR FILAMENTARY MATERIAL; LAYERED PRODUCTS; LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT ORNON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM; METALLURGY; ORGANIC MACROMOLECULAR COMPOUNDS; PACKAGES; PACKAGING ELEMENTS; PACKING; PERFORMING OPERATIONS; PRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCESIN A PLASTIC STATE; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDEDFOR; SHAPING OR JOINING OF PLASTICS; STORING; THEIR PREPARATION OR CHEMICAL WORKING-UP; TRANSPORTING; WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL; WORKING-UP

A polylactic acid resin foamed molding obtained by placing in a mold a cylindrical body having a foamed layer, which is formed by extruding a foamable molten resin composition prepared by kneading together a polylactic acid resin and a physical blowing agent from a die into a low-pressure zone, and molding it, wherein the molding's foamed layer constituting the foamed molding has a difference ( Hendo:2° C./min− Hexo:2° C./min) between the endothermic calorific value ( Hendo:2° C./min) and the exothermic calorific value ( Hexo:2° C./min) obtained by heat flux differential scanning calorimetry (heating rate of 2° C./min) of 10 J/g or more and a melt tension at 190° C. of 2 cN or more.