Duct tape must meet a series of standard tests described by the American Society for Testing and Materials. These methods measure two key properties of the adhesive: its adhesive strength which determines how well the tape will adhere to another surface and cohesive strength which shows how well the adhesive will stick to the cloth backing.
One common method of evaluating these properties involves applying the tape to a standardized stainless steel plate, and then measuring the force required to rip it off. The plate is then examined to determine how much, if any, of the adhesive residue is left behind.
The adhesive coating itself is monitored to evaluate how well it sticks to its backing. Conditions where the adhesive leaves a residue is known as creeping, crazing, oozing and bleeding. Quality control technicians also watch for fisheyes, the term used to describe an uneven application of adhesive.
In addition to the standard tests, each manufacturer has their own proprietary methods for evaluating their products. For example, companies may measure the duct tape's breaking point. Others evaluate the "scrunch" sound of the tape as it unwinds because consumers believe a noisy rip off the roll is a sign of strength.
Other tests are designed to measure quick stick. One way this is done is by shooting ping-pong balls at tape strips with the sticky side up to measure how far they roll before they are stopped by the tape.
Despite duct tape's reputation for superior adhesion, testing done by independent researchers has found that the tape does not work as well as it is intended to.
They designed an accelerated aging test that mimicked the temperature conditions of a home or office building from night to day and winter to summer. They used a series of standard finger joints which connected a smaller duct to a larger one. Wrapping each test connection with a different brand of duct tape, they evaluated the seal under temperature and humidity conditions designed to be similar to those found in home heating and air conditioning systems.
The researchers also performed a bake test in which the sample joints were baked at higher temperatures. However, the tape industry disputed these findings, claiming that for optimal efficiency their tape products should be assisted by collars or clamps. Environmental and price considerations drive researches to identify new adhesive formulations at a lower cost—general price for one 2 in 5 cm wide, 50 yd 46 m roll of all-purpose duct tape is about three dollars—that maintain high functionality with-out being damaging to the environment.
In addition, marketing considerations drive product improvements. In response to criticism that duct tape does not function well at extreme temperatures, manufacturers are creating more advanced formulations specially designed to withstand severe heat and cold fluctuations. For the first time, formal standards are being created specifically for duct tape to be used on flexible duct work. Tape manufacturers support this plan because they believe that certification by Underwriters Laboratories a product safety testing organization will boost their sales.
Berg, Jim, and Tim Nyberg. The Duct Tape Book. What is duct tape and why is it so strong? And is it duct tape or duck tape? From Insider , go inside a busy factory to see how layers of rubber for adhesive, a cotton cloth middle, and a backing made from polyethylene , a plastic often derived from petroleum or natural gas , come together to create this water-resistant invention.
Some World War II history:. A factory worker who was packaging ammunition sealed each box with tape and wax to make them waterproof. When the worker, Vesta Stout [ or Stoudt ], saw soldiers struggling to open the boxes, she came up with an idea to seal the boxes with a strong, cloth-based, waterproof tape.
Stout wrote a letter to [ Franklin D. There are so many options to choose from! There are several kind of tapes made from different materials and used in a number of applications that go far beyond simply mounting or sticking.
Take duct tape, for example. How did we ever manage without it? At the time, the US military used paper tape to seal their ammunition cartridges. They often had to be opened quickly to reload during battle, but were regularly not strong enough for this application. The paper tabs tended to rip off, making the tape difficult to remove and slowing the troops down during crucial moments.
An inspector at a rifle cartridge factory named Vesta Stoudt identified this problem and suggested an alternative solution: a stronger, polyethylene-coated cloth tape that could be easily torn by hand but was more resistant to water and accidental damage.
So she decided to directly send a letter to President Franklin D. Roosevelt outlining the problem and her solution, effectively inventing the modern duct tape. How the name originated is less clear, and there are a few conflicting stories. A factory worker who was packaging ammunition sealed each box with tape and wax to make them waterproof. When the worker, Vesta Stout, saw soldiers struggling to open the boxes, she came up with an idea to seal the boxes with a strong, cloth-based, waterproof tape.
Stout wrote a letter to FDR about her solution and a few weeks later, received word from the War Production Board that Johnson and Johnson would be manufacturing the tape. The tape became a military sensation. It was durable and easy to apply and remove by hand. After the war ended, duct tape turned up in hardware stores ready to help Americans with household repairs, too. It quickly became a useful tool for wrapping air ducts, which led to its other name, duct tape. Ashley Luke: Duct tape used to be kind of a one-and-done silver tape that was essentially used for repairs.
Our adhesive is specifically formulated to stick to a whole variety of different surfaces, and then basically the waterproof backing on top of that then protects the adhesive once it's applied to a surface. Narrator: There are three main components that go into making the tape. Rubber for the adhesive, cloth, and backing.
The rubber comes from rubber trees and arrives at the factory in large bales. A machine mixes the raw rubber along with various sticky resins until it reaches the consistency of pizza dough.
Then, the mixture is heated to over degrees Fahrenheit.
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