Multi-layered polylactic acid resin foamed body and multi-layered polylactic acid resin foamed molded article

• Main Authors: IWAMOTO AKIRA, TAKASE KENICHI, KAWADA TAKASHI
• Format: Patent
• Language: English
• Published: 08.03.2011
• Subjects: AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING; CHEMISTRY; COMPOSITIONS BASED THEREON; LAYERED PRODUCTS; LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT ORNON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM; MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONSONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS; METALLURGY; ORGANIC MACROMOLECULAR COMPOUNDS; PERFORMING OPERATIONS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDEDFOR; SHAPING OR JOINING OF PLASTICS; THEIR PREPARATION OR CHEMICAL WORKING-UP; TRANSPORTING; WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL

An object of the present invention is to provide a multi-layered polylactic acid resin foamed body of a crystalline polylactic acid resin which has good appearance and excellent mechanical strength such as bending strength and compressive strength and which is capable of being imparted with excellent heat resistance, and to provide a multi-layered polylactic acid resin foamed molded article having excellent appearance, heat resistance and mechanical strengh. The multi-layered polylactic acid resien foamed body of the present invention is a laminate having a polylactic acid resin foamed layer and a thermoplastic resin layer provided at least one side of the foamed layer, wherein the foamed layer has a cell shape satisfying specific conditions, wherein the difference ( Hendo:2° C./min− Hexo:2° C./min) between an endothermic calorific value ( Hendo:2° C./min) and an exothermic calorific value ( Hexo:2° C./min) of the foamed layer as measured by heat flux differential scanning calorimetry at a heating rate of 2° C./min is less than 40 J/g, and wherein the endothermic calorific value ( Hendo:2° C./min) is at least 10 J/g and the exothermic calorific value ( Hexo:2° C./min) is at least 3 J/g.