Supple bag made by flat assembly of a system of films intended to constitute, by extension, a stable recipient, and process for obtaining same

A process for obtaining a bag, intended to constitute, by extension, a supple recipient capable of being filled and closed, of the type comprising the flat assembly of a system of films constituted by at least one sheet and comprising an inner pleat in the form of a flattened V with substantially parallel and rectilinear edges, intended to constitute, after extension, the bottom of said recipient, and intercalated between two portions of sheet with substantially parallel and rectilinear edges, preferably superposed and merged with said edges of the inner pleat, and intended to form the lateral wall of said recipient, said assembly being made along lateral and bottom contours,

• said process comprising the additional step of assembling the films along a base line, not merged with said parallel and rectilinear edges of the films, defining the contour of the support base of the recipient, said lateral and bottom contours and said base line having been traced geometrically by developing on the plane of the films to be assembled the lateral surface of the recipient which was previously determined in its three-dimensional form, in order that said recipient rests, after being filled and closed, in stable manner on its support base, not presenting any point of fold along its lateral edges.