PLASTIC BAG IN WHICH SEALED PART INTERSECTING WITH PROJECTION PART IS CURVED LINE AND PREPARATION METHOD

摘要

PURPOSE: A plastic bag having an enhanced sealed part and a preparation method thereof are provided to disperse a pressure concentrated in an edge part and to prevent a decrease of a sealing strength. CONSTITUTION: The plastic bag(50) comprises both lateral sides(51) being folded to have a projection part(54) projected inside; and a lower side(53) having a sealed part by heat sealing. A sealed part intersecting with the projection part is a curved line. The preparation method of the plastic bag comprises the steps of: sealing the plastic bag in the piece by heat fusion in which a curved sealed line in a part intersecting with the projection part is formed; and producing the plastic bag by cutting one side thereof.