US Patent 7166344 Dust-free sealer for valve bags

The invention provides for a sealing device for a valve bag. The sealing device has two sections separated by a perforated seam. Each section is secured to one side of the valve channel and has an adhesive surface covered by a protective sheet. The two sections are perforated by the filling tube when the valve bag is filled, once the valve bag is filled the protective sheet is cleaned and removed and the two sections of the sealing device are pressed together and secured by the interaction of their adhesive surfaces.