Packaging case

A packaging case formed of a unitary blank of paper material comprising a bottom wall, a top wall and a back side wall connecting the bottom wall and the top wall, the unitary blank having:

• (A) at least two fold lines between which the back side wall is formed and both sides of which the bottom wall and the top wall are formed;
• (B) a plurality of score lines formed on the corner portions of the outer periphery of the unitary blank, the plurality of score lines being perpendicular to the edge of the unitary blank at the corner portions;
• and
• (C) incisions formed on both ends of each of the fold lines;
• the packaging case being formed by deep drawing the unitary blank, the packaging case comprising:
• the bottom wall;
• the top wall;
• the back side wall;
• a first side wall formed on the periphery of the bottom wall;
• a second side wall formed on the periphery of the top wall;
• a single first rim protruding outwardly from the upper end of the first side wall and being continuous substantially along the entire length of the first side wall;
• and
• a single second rim protruding outwardly from the upper end of the second side wall and being continuous substantially along the entire length of the second side wall;
• and the packing case is folded along the fold lines so that the first and second rims come into contact with each other, whereby the bottom wall, the top wall, the back side wall and the first and second side walls constitute an inner space.