Abstract: A releasable locking lid formed from a planar blank of paperboard material which is adapted to fit a locking style box and which can be formed using automated paperboard folding equipment. Fold lines are provided in selected locations in the paperboard blank to define a top wall and two pair of opposing side walls surrounding the top wall. Each of one pair of side walls are configured to form a double ply in the final form and include a pair of cut-out portions which form recesses on the inner side of the double ply side wall which mate with corresponding flaps provided on the box to releasably lock the lid on the box. The double ply side walls also include a flap portion on each end adapted to mate with a diagonally folded flap on the ends of the other pair of opposing side walls. These flaps are adhesively bound together to connect the side walls to one another.

Abstract: A container board for flat food products, made from a single piece of paper board such as a pizza, which includes a bottom wall surrounded by upright side walls and a pair of diagonally extending front corner walls is described and includes a lid portion having a top wall connected to a rearwardly disposed side wall of said bottom wall by a fold line forming a hinge. The lid portion is movable between a closed position covering the bottom wall and an open position. The lid walls are formed of a double ply having an upper edge provided with a top opening recess. The lid portion includes a top wall and said walls, the latter being conformed to be received in closely spaced relationship to the inner surfaces of the upright bottom side walls when the lid portion is in the closed position.