B65D 5/3621

Rigid or semi-rigid containers of polygonal cross-section, e.g. boxes, cartons or trays, formed by folding or erecting one or more blanks made of paper specially constructed to allow collapsing and re-erecting without disengagement of side or bottom connections {formed by folding or erecting a single blank to form a tubular body, at least one of the ends of the body remaining connected collapsed along two fold lines of the tubular body}