Use of polylactide and method of manufacturing a heat-sealed paper or board container or package

• Main Authors: KYLLIAINEN, OUTI, NEVALAINEN, KIMMO, ROSLING, ALI, RASANEN, JARI, KHAJEHEIAN, MOHAMMAD, LINDSTROM, ELLA, RIBU, VILLE
• Format: Patent
• Language: English
• Published: 07.07.2016
• 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; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDEDFOR; SHAPING OR JOINING OF PLASTICS; STORING; 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

The invention relates to use of polylactide (PLA) as an extruded polymer coating on paper or board intended for the production of containers and packages, which are heated in a stove or microwave oven. According to the invention a polyfunctional cross-linking agent, such as trialkyl isocyanureate (TAIC), is blended with PLA, and the extruded coating layer is subjected to cross-linking electron beam (EB) radiation. PLA may be used as such or blended with another biodegradable polyester such as polybutylene succinate (PBS). EB radiation has been found to improve adhesion of the coating to the paper or board substrate, heat-sealability of the coating, and heat- resistance of the finished containers and packages.