Leakproof packaging

A self-sealing, fluidtight bag having a bottom margin, side edges and an upper end, said bag comprising:

• a main body component fabricated of a flexible, impervious sheet material, said main body component having front and back walls and bottom and side margins and outer sides which are integrated along said bottom and side margins to define a compartment open at the upper end of the bag, said front and back walls having upper edges which both coincide with the upper end of the bag;
• a closure which extends from one side edge of the bag to the other, is integrated at a bottom margin thereof with one of said walls on the outer side thereof, and is displaceable over the upper end of the bag and into sealing engagement with the outer surface of the other wall,
• said bag having at least one line of adhesive extending from one side edge of the bag to the other side edge thereof for sealing said closure to said other of said walls coincident with its being brought into sealing engagement with said other wall, said line of adhesive also sealing said closure to said one wall when said closure is brought into sealing engagement with the other side wall to thereby promote the formation of a liquidtight seal at the upper end of the bag;
• the front and back walls of the bag being integrated by seams which extend continuously from the bottom margin of the bag to the upper end thereof at both of the side edges of the bag;
• and
• said seams so increasing in width over a span which is:
• (a) between the upper end of said bag and a level spaced downwardly from that end, and (b) overlaid by said line of adhesive as said closure is brought into sealing engagement with said other bag wall as to, (c) provide fluidtight seals at the upper end of the bag and at the side margins thereof between:
• (d) the front and back walls of the bag and (e) the closure and said other wall of the bag.