| 摘要 |
PURPOSE: A method of making a bag having a flat bottom and the bag made by the method are provided to make the bag having the flat bottom by using a flexible and thin material, not lowering resistivity of the bottom, in supporting objects to be carried. CONSTITUTION: A method of making a bag having a flat bottom includes steps of preparing a folded leaf comprising a first main flap(1a) and a second main flap(1b) overlapping one another, and a bottom edge(2) joining the main flaps; tucking in the folded leaf at the bottom edge to form first and second base strips(3a,3b) inserted between the main flaps; making, by a way of cutting and welding margins of the cutting, short furrows(6) extending between the base edges and the bottom edge, and spaced from one another according to the size of a flattened bag; turning up one base strip on one main flap to form triangular pockets(7) at the short furrows; fixing the triangular pockets to the base strips; and separating each bag from the folded leaf. The base strips form base edges(4a, 4b) with the main flaps. |
