Abstract: A free-standing container has a pair of like coextensive and outwardly convex side walls whose opposite lateral edges are heat-sealed together along straight seams to form an upright tube whose top and bottom are closed by respective upper and lower end walls each formed with a fold extending between the lateral edges of the side walls and each having a periphery subdivided into a pair of like sections by the respective fold line. Each section is joined to a respective side panel along a nonstraight seam line. This seam may be curved, in which case the end wall panels have circular or oval shape, or may be formed of a plurality of longitudinally joined straight sections in which case the end wall has a polygonal shape. The wall panels are all formed of a thermoplastic synthetic resin.