The invention concerns a manufacturing process for producing hermetic single-use food containers, including: forming a container body (30) having an peripheral rim (31), placing the container body in a sealing head having a first die (2) and a second die (8) having cooperating annular sealing surfaces (4, 10) facing the rim (31), sealing a closing lid (34) placed over the container body with the rim (31) by applying the first die (2) and the second die (8) one against the other. According to the invention, the first die (2) is provided with a continuous annular rib (6) in its sealing surface (4), the rib having a height (h) which is at least equal to a maximum depth of wrinkles that might appear on the rim upon forming the container body, whereby a sealing groove (12) is formed by the rib (6) in a side of the rim during the sealing.

An apparatus for producing containers from paper or paper-like material. The container has a lateral surface made of a wound sheet-like segment, of which segment edges arranged on longitudinal sides overlap and form a region of overlap, and a pan-like termination element. The lateral surface and the termination element are connected to one another in an essentially liquid-tight manner by a skirt, and at least one pressing ram is provided for pressing and sealing the skirt, the pressing ram subjecting the skirt to essentially radially directed pressure. The pressing ram has a radially projecting protrusion in a portion provided for the purpose of acting on a boundary portion of the region of overlap of the lateral surface of the skirt.

An apparatus for producing containers from paper or paper-like material. The container has a lateral surface made of a wound sheet-like segment, of which segment edges arranged on longitudinal sides overlap and form a region of overlap, and a pan-like termination element. The lateral surface and the termination element are connected to one another in an essentially liquid-tight manner by skirt, and at least one pressing ram is provided for pressing and sealing the skirt, the pressing ram subjecting the skirt to essentially radially directed pressure. The pressing ram has a radially projecting protrusion in a portion provided for the purpose of acting on a boundary portion of the region of overlap of the lateral surface of the skirt.