METHOD FOR PRODUCING FOAMED PRODUCT

• Main Authors: YAMAMOTO HIRONARI, ASARI TAKESHI
• Format: Patent
• Language: English
• Published: 10.04.2014
• Subjects: AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F,C08G; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING; CHEMISTRY; COMPOSITIONS BASED THEREON; COMPOSITIONS OF MACROMOLECULAR COMPOUNDS; GENERAL PROCESSES OF COMPOUNDING; MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVINGCARBON-TO-CARBON UNSATURATED 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; USE OF INORGANIC OR NON-MACROMOLECULAR ORGANIC SUBSTANCES ASCOMPOUNDING INGREDIENTS; WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL; WORKING-UP

PROBLEM TO BE SOLVED: To provide a method for producing a foamed product which suppresses the occurrence of silver streaks and dimples and is excellent in surface appearance.SOLUTION: There is provided a method for producing a foamed product, the method comprising the steps of: injecting a resin composition (X) including 70 to 90 mass% of a propylene-based polymer (A), less than 10 mass% of a copolymer (B) of ethylene and α-olefin, 10 to 30 mass% of an inorganic filler (C) (provided that the sum of (A), (B) and (C) is 100 mass%) and a foaming agent (D), or a resin composition (Y) including the propylene-based polymer (A), the copolymer (B) of ethylene and α-olefin, a melt-kneaded product obtained by melt kneading by adding an organic peroxide to the organic filler (C) and a foaming agent into a cavity in which gas is filled and pressurized; and after injecting the resin composition (X) or the resin composition (Y), expanding the cavity volume after 1 to 10 seconds to foam the resin composition (X) or the resin composition (Y).