Filament tape or strapping tape is a pressure-sensitive tape used for several packaging functions such as closing corrugated fiberboard boxes, reinforcing packages, bundling items, pallet unitizing, etc. It consists of a pressure-sensitive adhesive coated onto a backing material which is usually a polypropylene or polyester film and fiberglass filaments embedded to add high tensile strength. It was invented in 1946 by Cyrus W. Bemmels, a scientist working for Johnson and Johnson.
A variety of grades of filament tape are available. Some have as much as 600 pounds of tensile strength per inch of width. Different types and grades of adhesive are also available.
Most often, the tape is 12 mm (approx. 1/2 inch) to 24 mm (approx. 1 inch) wide, but it is also used in other widths.
A variety of strengths, calipers, and adhesive formulations are available.
The tape is most often used as a closure for corrugated boxes such as a full overlap box, five panel folder, full telescope box. “L” shaped clips or strips are applied over the overlapping flap, extending 50 – 75 mm (2 – 3 inches) onto the box panels.
Heavy loads or weak box construction may also be aided by the application of strips or bands of filament tape to the box.