US Patent 7144159 Gusseted reclosable package with slider-operated zipper

A side-gusseted bag having a slider-operated zipper. The zipper parts are joined only at one end, the free ends of the zipper parts being separable to allow the associated side gusset of the bag to be inverted to form a pouring spout. The zipper flanges at the joined ends of the zipper are inserted in a corner formed by one gusset panel and an opposing portion of the bag wall. The other gusset panel is sealed to the other bag wall at the elevation of the zipper flanges.