Masking tape, that creation, was intended to solve a very specific problem: applying two-toned paint jobs to cars, which were popular at the time. Before masking tape, auto shops were "masking off" for each color application using glue and paper. Peeling off the paper ruined countless paint jobs. Richard Drew, a young 3M research assistant, witnessed one such ruined job and the furious cursing that followed. Drew, who had absolutely zero experience in adhesives, decided, apparently on the spot, to create an adhesive that could be removed from dry paint without peeling it off [source: ACS ].
Two years later, masking tape was introduced. Gift-wrapping would never be the same. Nor would everyday household fixes.
During the Great Depression , when most people had to repair things like tablecloths and upholstery instead of replacing them, clear tape offered a fast, cheap, aesthetically satisfying solution. As a result, while many companies were closing their doors or barely getting by, Magic Tape kept 3M not just afloat but thriving [source: ACS ].
Today, adhesive tape comes in cellophane-finish for wrapping and matte finish for labeling. Hefty duct tape is a staple of many home repairs, while double-sided tape tacks up posters.
Brown tape wraps packages and stretchy adhesives work for bandaging. Joining two materials with tape has been so common for so long that people almost never think to ask "how does it do that? Turns out, tape is rather remarkable. It's not adhesion itself but the specific type of adhesive used on tape that makes it indispensable in daily life.
The "sticky" used in sticky tape is different in that it relies primarily on physical processes, not chemical ones, to adhere. Adhesion certainly didn't begin with tape. Woodworkers in ancient Egypt used natural glue made from animal collagen. Natural, viscous substances like beeswax and resin have always held materials together effectively [source: THToC ]. In modern times before tape, glues and epoxies did most of the sticky work.
But they had serious drawbacks, especially in household use. Messiness, permanence and drying to a hard finish all made traditional glues , which typically bond by chemical means, less-than-great for small, quick everyday jobs. The adhesives used in tape work differently. They're called pressure-sensitive adhesives PSA and include materials like silicones, acrylics and rubbers -- all polymers to which a tacky resin is added to increase stickiness [source: ThomasNet ]. These PSAs rely on physical reactions, not chemical ones, to adhere.
This contributes to qualities like removability and flexibility -- some of the stuff we love most about tape. In a pressure-sensitive bond, there are two main processes at work: wetting and van der Waal's forces. The former establishes adhesion. The latter makes it stronger [source: Hyperphysics ].
Wetting is pretty simple. In this case, it refers to the way a solid adhesive penetrates a substrate the material the tape is applied to. The solid adhesive used in tape is good at wetting because it has a low surface energy , meaning its surface molecules are moving around a lot, or are energized, causing looser bonds.
Temperature, weather, surface conditions, chemistry and application all play vital roles in sticky success — or failure as the case may be. Since there are so many factors that go into the effectiveness of tape, we created a checklist to help you troubleshoot your sticky issues. Are the conditions different — colder, wetter, hotter? Did you apply it differently? Ideally, the surface must be clean, dry, and oil free.
When in doubt, wash the surface with rubbing alcohol and dry it thoroughly with a soft cloth. Or do you have a rough surface that leads to minimal contact and requires a thick adhesive? Try testing the tape on a flat, clean surface metal or glass always works well , and see if your tape adheres well there. If so, your problem may be a rough surface. Some surfaces like polyethylene or PVC or concrete are especially hard to adhere. A tacky tape will help, but if not, try a different roll and see if the trouble persists.
Or as described above, try the tape on a flat, clean glass or metal surface. If it sticks well, chances are the problem is the surface and not the tape. If so, remember that cardboard is sometimes made from recycled material, which tends to have many small fibers on the surface that break away very easily.
You may need a tape that is designed explicitly for recycled cardboard. Like most products, adhesive tapes will deteriorate over time and lose their adhesive properties. Does your problem disappear when a fresh roll of tape is used? Learn more about cold weather issues here. It may seem simple, but knowing how to apply tape properly plays a huge role in whether or not the adhesive sticks.
In fact, it may be the surrounding conditions or even the surface that you are trying to stick the tape to. These can include several variables:. Carefully factor in the temperature. The tackiness of the adhesive tape is very temperature-dependent, and the colder the conditions, the poorer the bond will be.
If you must work at lower temperatures, then use an adhesive tape specifically designed for colder climates. Surface: Is the surface clean? Traces of dust, dirt, grease, and even the slightest trace of moisture will contaminate the adhesive surface and act as a barrier between the two. To best prepare, the surface, give it a quick wash with rubbing alcohol and dry it with a clean cloth.
The typical adhesive tape has a very thin, flat smooth layer of adhesive. Is your surface also flat and smooth, so that the two can uniformly contact one another? With a moderately rough surface, you will need a tape with a much thicker adhesive that can fill these valleys, thus providing a major improvement in contact.
If it is too rough, then you may need a foam tape with enough deformation to make a good bond. Is the surface you are working with a plastic or other material? Is it covered with paint or another coating that has a naturally low adhesion or even release quality? A very tacky tape will help, as well as tapes with an adhesive that is based on natural rubber, but you may need to turn to an adhesive tape specifically designed for your specific surface.
As a very last resort, you may need to change the character of your surface to get an adhesive tape to stick to it. This could mean roughening it with an abrasive or even treating it with a prime coat that is compatible with both the surface and the adhesive.
There are two ways to do this: Real-world field testing and lab testing. Ideally, we get to do both, like at The Durability Lab , but the bottom line is that the real world test matters most. Not good at all. One of the most critical aspects of our application trials is to test the tape on the actual substrate which is where real-world applications come into play.
For years, lab tape testing was performed on standardized substrates, like steel, and it did not differentiate performance based on a specific material. Over the last five decades, we have learned how critical a factor this is. The tape may work on one specific substrate and fail on others. Sometimes the tape works on a substrate, but when any changes to the chemistry or condition of the substrate change, the tape could end up failing. Even a small change can have a major effect.
Take, for example, splicing tapes. In many situations, customers need a quick stick while materials are still moving called a flying splice , but then the tape needs to permanently adhere for long-term performance. We first test splicing tape by hand on the substrate — paper, cardboard, flexographic materials — and then see if it pulls fibers.
This is good because this shows that the tape has a quick stick. Then, we move it to the actual machine for real-world testing. A splice can take a blink of an eye and so you need to test the tape in the manufacturing process.
Which one you want makes a difference in how you test tape. Here are some more behind-the-scenes insights to our application testing process.
For temporary bonding , we are trying to discover whether tape adheres quickly and comes off cleanly.. In this scenario, we will apply the same environmental conditions to the adhesives, and see how it performs.
Does it apply quickly and evenly? Does it remove easily and without residue? Permanent bonding is a different animal. Oftentimes, the tape needs to cure to assess performance, like acrylic adhesives that need 72 hours to set. There are two common real-world tests we use here:.
UV light is a type of electromagnetic radiation, as are radio waves, infrared radiation, X-rays and gamma rays. With prolonged exposure to ultraviolet light, certain chemical materials, such as natural and some synthetic rubbers as well as polyethylene, can experience negative changes to their properties; resulting in them becoming hard and brittle.
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