Method for manufacturing a bag

A method for manufacturing a bag comprising:

• providing a first side wall;
• providing a second side wall, the second side wall joined to the first side wall to define a first side end, a second side end, a closed bottom end and an open top end;
• providing a retaining element having a length and width, the retaining element comprising an activatable elastic material, having a first condition wherein the retaining element is set and a second condition wherein the retaining element is urged to shrink a predetermined amount, the material is changing from the first condition to the second condition upon being activated;
• attaching a portion of the width of the retaining element in the first condition along its entire length continuously to one of the first and second side walls adjacent the top end such that the retaining element extends longitudinally between the first and second side end a predetermined length to thereby define an attached portion and an unattached portion;
• and
• activating the retaining element to shrink the width of the side wall and thereby reducing the size of the open end of the bag to provide a shirred appearance to the bag.