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Methods for Lowering Melt Viscosity and Improving Heat-sealability of Polyester and for Manufacturing a Heat-sealed Container or Package

Research output: PatentScientific


Original languageEnglish
Patent numberUS2017008226
IPCB29C 71/ 04 A I
Priority date22/01/15
Publication statusPublished - 12 Jan 2017
Publication typeH1 Granted patent


The invention relates to methods for lowering the melt viscosity and thereby improving heat-sealability of a polyester. The invention also relates to a method for manufacturing a heat-sealed container or package from fibrous- based, polyester-coated packaging material, and a method for heat-sealing polyester. The solution according to the invention is subjecting polyester to electron beam (EB) radiation. The lowered melt viscosity allows a lower heat-sealing temperature, and permits sealing of polyester to an uncoated fibrous surface. The preferred polyester for the invention is polylactide, as such or as blended with another polyester.

Field of science, Statistics Finland