Scotch Tape Can Create X-Rays, and More You Didn’t Know About The Sticky Stuff

Depending on who you ask, Scotch tape was first marketed on this day either in 1928 or 1930. What’s safe to say is that the sticky-but-not-too-sticky substance has been helping us hold our lives together for most of a century. But you might not know everything about the roll in your kitchen drawer.

1. It generates X-rays

Don’t worry, this won’t happen the next time you use it to wrap presents: Scotch tape only generates the body-imaging rays if you peel in it a vacuum.

Triboluminescence, the phenomenon behind the glow of Scotch tape, is a kind of energy release that happens “whenever a solid (often a crystal) is crushed, rubbed or scratched,” Katharine Sanderson writes for Nature’s news blog. Think Wint-O-Green Life Savers.

Why precisely sticky tape — with its non-crystalline adhesive — gives off so much energy is a mystery at this point, Sanderson writes. The UCLA researchers who studied the phenomena weren’t expecting the strength of the rays, which was enough that they actually X-rayed a finger using little more than their apparatus and dental film.

You can see the research in action on Nature’s website.

2. Its origins have nothing to do with Scottish people or culture, in spite of its tartan branding

Before Scotch tape and its direct predecessor, Scotch Brand Masking Tape, the tapes that were commercially available were all much stickier. In fact, it was the problems created by this extreme stickiness that led to the development of the new products in the first place, writes Sarah Stone for Today I Found Out.

“In the 1920s, a two-tone paint job was popular for cars and a headache for automotive painters,” she writes. They created the two-tone look by painting the car a single color, applying a barrier around the area due for tone 2, and then painting inside the lines.

But the adhesives of the day weren’t right for the task, she writes: “Some automotive shops would glue newspapers over the already painted sections while others used tape to prevent paint transfer. However, those techniques often left a sticky residue on the paint that was difficult to remove. Sometimes, it would even mean the painters had to do the entire paint job over again.”

When Richard Drew, who worked for the 3M company, found out about this issue while delivering sandpaper (then 3M’s primary product) to auto body shops, he developed masking tape to solve it. But, the story goes, the painters were concerned that the company had been “Scotch” with the adhesive on the tape. At the time, “Scotch,” referring to Scottish people, was a racist slang for “cheap.”

3. Its recipe is a secret, but we can guess what’s in it

3M keeps their recipe for the clear Scotch tape’s “sandwich of polymers and carefully engineered chemicals” tightly under wraps, writes Chelsea Leu for Wired. But the magazine did its own research on what might be in the tape.

Their take: cellulose acetate, acrylics, de-ionized water, silicone and something like polyurethane. Sure is a lot for something you use to stick paper together.

4. It was invented to solve industry problems with using the newly-invented cellophane.

In 1929, four years after Scotch Brand Masking Tape was introduced, Drew was working on a new industrial problem for a company called Flaxlinum, writes the American Chemical Society. In the end, the company moved on, but in the course of coming up with a solution, he invented the pressure-sensitive tape backed with cellophane, which had been recently developed by DuPont.

“Bakers, meat packers, grocers and confectioners who had adopted cellophane food wrap were clamoring for a moisture-proof and attractive way to seal their new packaging,” the ACS writes. This need convinced Drew, now technical director of 3M’s Product Fabrication Laboratory, that they should keep doing R&D on the product. By 1930, the product was out the door.

5. In the Depression (and after), you used Scotch tape to fix everything

“In an era where thrifty wasn’t just a virtue, but a necessity, Scotch Brand Cellulose Tape virtually sold itself,” writes the ACS. The clear tape was used to repair a myriad of things: paper pages and even paper money, window curtains, damaged manicures, cracked ceiling plaster, and even—still a common use today—for de-linting clothing.

But it also had more pedestrian uses. One 1940s Scotch tape ad even shows a woman grimacing in consternation as her lunch, wrapped in slippery paper, falls to the subway floor on the way to work:

LOST: One ham on rye

WANTED: A roll of good old “Scotch” tape to seal lunch packages

Kat Eschner | | READ MORE

Kat Eschner is a freelance science and culture journalist based in Toronto.