Raw Materials
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Cotton mesh Cotton mesh forms the backbone of duct tape. It provides tensile strength and allows the tape to be torn in both directions. Cloth that has a tighter weave and higher thread count is of a higher quality, provides greater strength, and gives a cleaner tear. A premium quality tape can have a thread count of 44 by 28 threads per square inch. Accordingly, tape made with this fabric is more expensive. The cotton fabric is called a โwebโ when it is spread across the coating machinery.
Polyethylene coating The cotton fabric is coated with polyethylene, a plastic material that protects it from moisture and abrasion. This plastic coating is flexible and allows the tape to adhere better to irregular surfaces. The polyethylene is melted and applied to the fabric in a preliminary coating operation. The coated fabric is then stored on rolls until the manufacturer is ready to apply the adhesive.
Adhesive compound The adhesive used in duct tape is unique for two reasons. First, the adhesive itself is formulated with rubber compounds that ensure long-term bonding. Other tapes typically use adhesive polymers that are not as binding. Second, the adhesive is applied to the substrate in a much thicker coating than those used on cellophane or masking tapes. This too serves to increase the adhesive properties of the tape.