The History of Duct Tape
In 1943, Vesta Stoudt had a job in a munitions factory where ammo cases were sealed with paper tape and melted wax. Worried the cases were too hard to open on the battlefield, Stoudt proposed a fix: Use waterproof cloth tape instead.
Johnson & Johnson adapted surgical adhesive tapes to Stoudt’s specifications, and soldiers nicknamed the material “duck tape” in reference to its ability to repel moisture “like water off a duck’s back.” (They also dubbed it 100-mph tape because it could hold together a speeding jeep!)
Following World War II, duct tape began to catch on in the U.S. as a handy tool for home construction. People were using it to hold metal air ducts together, so the company rebranded the product as “duct tape” and updated it with a matching silver color made from powdered aluminum.
Thus, duck tape became duct tape.
How Does It Work?
Duct tape relies on what’s known as a pressure-sensitive adhesive (PSA) for its inherent stickiness. PSAs are soft polymer blends that exploit van der Waals forces to join two objects together. The strength of the bond is due to the fact that the adhesive is hard enough and its viscoelastic properties are powerful enough to resist flow when stressed. This is not the same as the mechanics of structural adhesives like, say, Elmer’s glue. Those adhesives require the evaporation of a solvent to create a chemical bond.
Interestingly, its namesake usage (“duct”) is one of the few things that duct tape isn’t recommended for. Lawrence Berkeley National Laboratory conducted tests in 1998 to see how well different types of tape performed at sealing ducts, and, compared to the other products, duct tape was the clear loser. Using duct tape on actual ductwork is now considered a code violation in many buildings.
Mythbusters has devoted three entire episodes to exploring some of duct tape’s most extreme applications. The team was able to successfully use duct tape to patch a damaged airplane fuselage, construct a functioning cannon, build a usable bridge, and lift a 5000-pound car. Of the 18 myths they tested, only one was busted (turns out you can’t use duct tape to barricade a car driving at 60 mph).
7 Types of Duct Tape — Are You Using the Right One?
Duct tape’s initial design was simple but effective: a strong fabric bonded to polyethylene film for sealing/waterproofing, silver-grey colouring to match metal ductwork, and a thick coating of adhesive to seal the joints and make them airtight.
But people quickly determined that this speciality tape could be used for a variety of other purposes, and the boom was on. Many new versions were manufactured – each with different qualities of the fabric, polyethylene, and adhesive – for many different end-uses. As a result, manufacturers now offer a wide range of grades of polyethylene/fabric types and in a wide variety of colors.
1. General Purpose
With a low fabric count, a thin polyethylene film, and a low weight adhesive, general-purpose tapes work well enough for odd jobs where long service life isn’t necessary.
2. Industrial Grade
With industrial-grade tapes, the fabric and polyethylene are upgraded, so the tape becomes more of a “workhorse” with added adhesive coating weight. One popular variation is multi-colored industrial tape that is used to seam and hold carpets at exhibitions, where the adhesive must be removed cleanly.
3. Professional Grade
Sometimes called “contractors’ grade” these tapes offer more of an upgrade to the components of the industrial-grade tape for added strength, adhesion, and durability.
4. Gaffer’s Tape
Typically, gaffer’s tape is a matte black for minimal light reflection and is used in movies, television, and photo studios to temporarily tape cables to the floor or light fixtures to vertical posts. This type of tape needs to be able to be easily torn by hand and remove cleanly.
5. Stucco Tape
Stucco tape is used to attach protective polyethylene film over doors and windows during house construction prior to spraying the outside walls with stucco. Stucco tape is designed to be used outdoors for several days at a time, so it must be able to resist the ultraviolet of the sun’s rays during that time – and not come apart from the vinyl window frames.
6. True Duct Tape
This one lives up to its name – duct tape is truly intended for sealing air ducts. Duct tape must be permanent and able to withstand the prolonged heat and air pressure for the lifetime of the duct. It may even need to be flame retardant to meet some building codes. Duct tape is the true top of the line, a high tensile, hardworking tape.
7. Coated Cloth Tape
A roll of coated cloth tape has gone with every U.S. manned space launch, and is also commonly known as “Mission Tape.” This tape played an essential role in the construction of the carbon dioxide absorbers which saved the lives of the three astronauts in the ill-fated Apollo 13 mission.
With such a wide variety to choose from, start by considering exactly what you expect your tape to do. Then, evaluate the right polyethylene/fabric backing judged by tensile strength, as well as the right adhesive coating thickness, judged by adhesion level, for the best performance with the lowest cost.