Abstract A paper bag having a substantially rectangular cross section and made of a single tough but cheap paper material and provided with a flexible and tough reinforcement wire or band lined along the entire open top edges and also with intermediate vertical folding lines in the side panels, at least one horizontal folding line extending around the vertical panels in the lower portions of these panels, inclined folding lines extending inwardly from the corners of the bottom side edges to join the point of intersection of said intermediate vertical folding line and said horizontal folding line, and at least one longitudinal central folding line in the bottom panel, whereby said paper bag may be retained in each of the opened and the closed configurations by virtue of said reinforcement means.
A paper bag according to claim 1, characterized by: said bottom panel being provided with extension folding lines aligned with said longitudinal folding line in the center of said bottom panel and extending up to the side edges of said bottom panel, and also being provided with inclined folding lines extending inwardly from the corners of both sides thereof in such a way that those extending from the corners of the same side edge join each other at the point of juncture of said longitudinal folding line and one of its extension folding lines extendIng in the center of said bottom panel, said inclined folding lines of said bottom panel extending from the corners of each of the side edges being symmetrical with the similar inclined folding lines extending from the corners of the opposite side edge, so that the paper bag may be folded symmetrically along said vertical folding lines so that the inner surfaces of said side panels, folded along said vertical folding lines, are brought into uniform, flat contact with the inner surface of said front and rear panels.
Claim 2
Dependent Claim
248 words
A paper bag according to claim 2, characterized by: all of said four side, front and rear panels being provided with aligned horizontal lines in the upper portions of said panels so as to be spaced from the open top edges and also from said first occurring horizontal folding lines formed in the lower portions of said panels, wherein said side panels are provided with inclined folding lines extending inwardly from the corners of the open top edges of said side panels in such a way that those extending from the corners of the same side edge of each of said side panels join each other at the point of juncture of said secondly occurring horizontal folding lines formed in the upper portions of said side panel and said intermediate vertical folding line formed in said side panel, and said inclined folding lines being quite symmetrical with those in the lower portions of said panels, so that the paper bag may fold not only along said vertical folding lines, but also along said inclined folding lines in such a way that said inclined lines in each pair of opposing or corresponding lines in the upper and lower portions of said side panels are brought closer to each other, respectively, and said paper bag can be folded in opposite directions along said horizontal folding lines in the upper and lower portions of said front and rear panels so as to close the open top of said paper bag completely.