US Patent 7325688 Pressurized water-soluble pouch

A pressurized pouch is made of a water-soluble material, preferably PVA film, to hold a concentrated product for later mixing in a bottle to provide a water solution. Because of the interior pressure, the water-soluble pouch retains a semi-rigid resilient shape that greatly facilitates its introduction through the neck of the bottle. The pressurized pouch can be made by either VFFS or HFFS machines wherein a puff of air is added prior to sealing. Alternatively, the pouch is made by filling it in a pressurized chamber.