The present disclosure relates to a method of forming a paperboard packaging container from a rectangular body blank, the method comprising the steps of providing a rectangular body blank having a first end edge and a second side edge, forming a tubular container body from the rectangular body blank, sealing together the first and the second side edge of the body blank, closing the first end opening by pressing a paperboard disc into the first end opening, pressing the first end of the tubular container body into a curl forming portion of a curling tool, filling the packaging container with bulk solids, and closing the second end opening.

A curled-edge and double-layered cup includes an outer cup unit including an outer base wall, an outer surrounding wall, and an outer top wall, and an inner cup unit disposed within the outer cup unit. The inner cup unit includes an inner base wall disposed above the outer base wall, an inner surrounding wall surrounded by the outer surrounding wall, and a curled-edge unit enclosing the outer top wall. The curled-edge unit includes an inner top wall disposed above the outer top wall, and an outmost surrounding wall having a surrounding portion connected to the inner top wall and surrounding the outer top wall, and a bottom seal portion extending inwardly from the surrounding portion and disposed under the outer top wall.

A curled-edge and double-layered cup includes an outer cup unit including an outer base wall, an outer surrounding wall, and an outer top wall, and an inner cup unit disposed within the outer cup unit. The inner cup unit includes an inner base wall disposed above the outer base wall, an inner surrounding wall surrounded by the outer surrounding wall, and a curled-edge unit enclosing the outer top wall. The curled-edge unit includes an inner top wall disposed above the outer top wall, and an outmost surrounding wall having a surrounding portion connected to the inner top wall and surrounding the outer top wall, and a bottom seal portion extending inwardly from the surrounding portion and disposed under the outer top wall.

The present disclosure relates to a method of forming a paperboard packaging container from a rectangular body blank, the method comprising the steps of providing a rectangular body blank having a first end edge and a second side edge, forming a tubular container body from the rectangular body blank, sealing together the first and the second side edge of the body blank, closing the first end opening by pressing a paperboard disc into the first end opening, pressing the first end of the tubular container body into a curl forming portion of a curling tool, filling the packaging container with bulk solids, and closing the second end opening.