Abstract: This invention relates to a method of forming a bag. The method includes the step of forming a line of weakness in a portion of material being used to form a part of the bag, placing a patch over the line of weakness, and forming the bag. The arrangement and construction is preferably such that the patch is located substantially inside the bag thus formed. The line of weakness and patch may preferably act as a self-closing opening for the bag. A bag which includes such a self-closing opening, and bag machinery used for forming such a bag, are also described.

Abstract: The present invention relates to a multi-layered bag which includes an inner bag located within the interior of an outer bag, where the outer bag including a first and second region of weakness. The inner bag includes a region of weakness adjacent to the outer bag's second region of weakness. The multi-layer bag has the inner and outer bags sealed closed and together adjacent to the outer bag's second region of weakness. A method of manufacturing such a multi-layered or composite bag is also disclosed.