[POPSCI]The 11-Year Quest to Create Disappearing Colored Bubbles

The 11-Year Quest to Create Disappearing Colored Bubbles
By Mike Haney | December 2005
Chemical burns, ruined clothes, 11 years, half a million dollars—it's not easy to improve the world's most popular toy. Yet the success of one inventor's quest to dye a simple soap bubble may change the way the world uses color

Tim Kehoe has stained the whites of his eyes deep blue. He's also stained his face, his car, several bathtubs and a few dozen children. He's had to evacuate his family because he filled the house with noxious fumes. He's ruined every kitchen he's ever had. Kehoe, a 35-year-old toy inventor from St. Paul, Minnesota, has done all this in an effort to make real an idea he had more than 10 years ago, one he's been told repeatedly cannot be realized: a colored bubble.

No, not the shimmering rainbow effect you see when the light catches a clear soap bubble. Kehoe's bubble would radiate a single, vibrant hue throughout the entire sphere—a green bubble, an orange bubble, a hot-pink bubble. It's a bubble that can make CEOs giggle and stunned mothers tear up in awe. It's a bubble you don't expect to see, conditioned as you are to the notion that soap bubbles are clear. An unnaturally beautiful bubble.

Kehoe made a bubble like that when he was 26, after only two years of trashed countertops and chemical fires. He showed it to toy-company executives, who called it a "holy grail." And then it broke, as bubbles always do. And when it did, the dye inside escaped onto clothes and carpets and walls and skin, staining everything it touched. The execs told him to come back with a bubble they could wash off their boardroom table.

That was nine years ago. In the intervening years, Kehoe continued to mix, boil, and brew with endless enthusiasm and little success. Until one day, his stubborn persistence led him to $500,000 in financial backing, enough to hire a dye chemist. Together, they took Kehoe's obsession to an outcome even more amazing than he had ever hoped, an outcome no one could have anticipated for the simple reason that no one imagined it possible. The secret to nonstaining colored bubbles, it turns out, is a dye that could unlock a revolution in color chemistry. All you need to do is make color disappear.

Anatomy of a Bubble
...
In the world of toys, where the average shelf life of a product is less than 18 months, bubbles are a juggernaut. A Chicago company called Chemtoy began selling bubble solution in the 1940s, and the fad never wore off. According to one industry estimate, retailers sell around 200 million bottles annually—perhaps more than any other toy.

Despite their enduring appeal, bubbles haven't been improved much in 60 years, the only significant exception being in 2002, when SpinMaster in Toronto introduced Catch-A-Bubble, clear bubbles that lasted as long as five minutes. Time magazine called it one of the year's top inventions, and seven million bottles sold the first year.

The market for lasting bubbles is the same as the market for clear bubbles: elementary-school kids. If an inventor could somehow add color, though, suddenly adults might have reason to start blowing again. Picture bubbles in NFL team colors, or bubbles that match charity ribbons. The potential market would grow to include every man, woman and child. So why don't they exist?

It turns out that coloring a bubble is an exceptionally difficult bit of chemistry. A bubble wall is mostly water held in place by two layers of surfactant molecules, spaced just millionths of an inch apart. If you add, say, food coloring to the bubble solution, the heavy dye molecules float freely in the water, bonding to neither the water nor the surfactants, and cascade almost immediately down the sides. You'll have a clear bubble with a dot of color at the bottom. What you need is a dye that attaches to the surfactant molecules and disperses evenly in that water layer. Pack in more dye molecules, get a deeper, richer hue. Simple. Well, on paper anyway.

Toy Story
...
What drove him crazy was a single question, one that taunted him with every clear bubble that came off his wand: Why can't it be done?

A Burst of Color
Color remained elusive, but his try-anything approach kept plenty of other strange bubbles floating across his kitchen. One exploded with a loud bang. Another gave him chemical burns when it popped. The best one bounced, just like a Super Ball. He thought he could have sold that one, but he couldn't re-create it. He could rarely re-create any of his experiments. "I never wrote anything down," he says. "I'd get too excited as I was doing it. But once I lost that bouncing bubble, I was crushed. I started videotaping myself so that next time I'd know more than ‘It was something on that side of the kitchen.' "

Ask Kehoe now to describe the day the first colored bubble appeared, and the details are fuzzy. He remembers dipping his wand into a pot of blue solution (although they produced clear bubbles, most of his solutions were colored by then) and looking at the quivering film, thinking that this one seemed different. He blew, and a bubble floated across the room. It was blue. He tried again. The next bubbles were blue too. He called Sherri in to make sure he wasn't hallucinating. No, she agreed, it was a blue bubble. As far as they knew, the world's first blue bubble. In his kitchen.

How could this be? He hadn't added any special ingredient. He was just playing around with the variables—heating this a little longer, dumping in this before that—and something worked. How didn't matter. Kehoe wasn't after a theory; he was after a bubble, and that he had, on videotape. As far as he was concerned, the project was finished. All that was left was to collect his license deal. So he started showing his tape to toy companies.

"A guy at Hasbro told me they had tried it for two years, and mine were better than anything they had seen, visually," Kehoe says. Every executive who saw them was stunned by their beauty, and everyone told him they could put clear bubbles out of business.

"The problem," Kehoe says, "was that if the bubbles touched you, they stained your skin for weeks. It ruined everything. Everybody said the same thing: Call me when you get it right. So I went back to work."
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Partners in the Bubble Lab
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With his bubbles staining boardrooms across the country and a new baby and house to pay for, Kehoe had to move on. What he did with those next eight years—starting a Web-design business, then moving to another company (where I first met him)—isn't really important but for one key event. In 2003 the software company he was working for was sold, putting him out of a job and making its founders rich. This inspired him to return to toys full-time, and the founders' fond opinion of Kehoe inspired them to launch a new toy company with him, 50-50. Kehoe threw in 219 ideas; they threw in half a million dollars. Only after the deal was secure and Kehoe cashed the check did he tell them about the bubbles.

...

"Then one of the inks worked. It made the most wonderful colored bubbles I had ever seen. And they washed off my skin without scrubbing. I had never tried it because it was a pigment-based product, and I gave up on pigments years ago [because they tend to stain more than dyes]. But these behaved more like dyes and were skin-washable." Kehoe and Sherri dumped the solution on their clothes and kids, and every time it washed out. When Haddleton saw the bubbles on Monday, he was thrilled.

...

Play Date
In July 2004 Kehoe and his partners invited dozens of kids and their parents to Haddleton's estate on Sunfish Lake, near St. Paul, for a bubble unveiling and focus-group party. They hired a film crew and rented massive bubble machines to fill the air with the washable solution that, they figured, would be on store shelves in a matter of months.

The first five minutes of the party were stunning. Mothers gasped, and a few were even moved to tears, at the initial sight of the strangely vivid orbs almost glowing in the sunlight. Kids shrieked and chased after them. It was the moment Kehoe had pictured all those years—not big checks or fame, just seeing this project reach its end in a single joyous afternoon.

And then the bubbles broke—on the kids, on the parents, on cars, on Haddleton's prized German shepherds. It looked like there had been a paint fight. Kehoe had told the parents that the color would wash out, but it didn't matter. Not when their children were covered head to toe in blue and pink splotches, when the color was getting into their shoes and hair and soaking into the concrete. In the faces of the horrified mothers, Kehoe immediately grasped the lesson. "You can't go to market with something that leaves that much color, even if it is washable," he says. "It freaks people out."

Just when he thought he'd succeeded, he'd failed again. Washable wasn't good enough. He needed color that disappeared on its own, that would never stain any surface it touched. But in the history of organic chemistry, no one had ever created a water-soluble dye that disappeared on its own. And Kehoe, despite his years of tinkering, was no chemist.
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Calling in the Expert
Ram Sabnis is a leader among a very small group of people who can point to a dye-chemistry Ph.D. on their wall. Only a handful of universities in the world offer one, and none are in the U.S. (Sabnis got his in Bombay). He holds dozens of patents from his work in semiconductors (dying silicon) and biotechnology (dying nucleic acids).

Sabnis wasn't the first chemist to reply to Kehoe's deliberately vague Monster.com ad. He was just the first one who didn't think that what Kehoe and his partners wanted—a water-soluble disappearing dye that could color the very thin wall of a bubble—was impossible. Sabnis told them he'd have it ready to market in a year. Like Kehoe, Sabnis doesn't seem to consider the possibility that a problem can't be solved. But even he had no idea how hard this one would turn out to be

....

The breakthrough finally happened in an empty lab in Minneapolis on a Sunday this past February. As with Kehoe's first bubble, it arose from the slow, subtle refinement of a process over thousands of experiments. But Sabnis could re-create it. He synthesized a dye that would bond to the surfactants in a bubble to give it bright, vivid color but would also lose its color with friction, water or exposure to air—not fade, not transfer to something else, but go away completely, as though it had never been there. When one of these bubbles breaks on your hand, rub your hands together a few times and look: Poof. Magic. No more color. If the bubble breaks on your shirt or the carpet or the dog, you have two choices: Dab it with a touch of plain water to remove it immediately, or forget about it for half an hour. Either way, the color will soon be gone.

Sabnis's solution was to build a dye molecule from an unstable base structure called a lactone ring that functions much like a box. When the ring is open, the molecule absorbs all visible light save for one color—the color of the bubble. But add air, water or pressure, and the box closes, changing the molecule's structure so that it lets visible light pass straight through. Sabnis builds each hue by adding different chemical groups onto this base.

"Nobody has made this chemistry before," Sabnis says. "All these molecules—we will make 200 or 300 to cover the spectrum—they don't exist. We have synthesized a whole new class of dyes." Sabnis also impressed Darlene Carlson, a former 3M chemist who helped Kehoe and his partners write the job ad. "What Ram did was an extremely difficult bit of chemistry," she says. "Somebody without his experience in dyes would not even know where to start."
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Introducing Zubbles
Colored bubbles will hit shelves this February, if not sooner, under the brand name "Zubbles." The bottles are shaped like little bubble characters. Each color has its own name and personality—Zilch, the villain in black, is a favorite among boys. Girls prefer the pink Zilli. Kehoe is in talks with several major toy companies, and this time, they're begging him for a deal. Even though bubbles are a traditional summertime toy, Toys-R-Us told him that he'd be a fool not to have the bubbles in stores by Christmas. As Popular Science went to press, Kehoe was looking for a partner with a factory that could keep the formula secret and crank out a million units in six weeks.

When Kehoe isn't blowing bubbles for businessmen, he's at home inventing again, coming up with new uses for the disappearing dye, the importance of which is hard to overstate. For decades, the color industry has been focused entirely on color fastness. No one has really thought about the potential of temporary color. That the dye was created for children's bubbles may turn out to be just a footnote, a funny story Sabnis tells at color-chemist conventions.

Among the ideas Kehoe has already mocked up are a finger paint that fades from every surface except a special paper, a hair dye that vanishes in a few hours, and disappearing-graffiti spray paint. There's a toothpaste that would turn kids' mouths a bright color until they had brushed for the requisite 30 seconds, and a soap that would do the same for hand washing.

He's also thinking outside the toy chest, mucking around in the lab on weekends making things like a Swiffer that leaves a momentary trace showing where you've Swiffered and a temporary wall paint that would let you spend a few hours with a color before committing to it. The dye's reach is so great that there are even biotech and industrial uses being discussed. "We've got stuff in the works I can't talk about that'll blow bubbles away," he says excitedly. It might take years, but, knowing Tim Kehoe, we'll see them eventually. After all, it's only a little extra work.

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