The 11-Year Quest to Create Disappearing Colored Bubbles

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

Tim Kehoe is just over six feet tall, with a build he prefers not to call "portly." He lives in an old brick house in St. Paul, across the street from the elementary school he attended and where two of his four kids now go. He is the embodiment of phrases like "Minnesota nice" and "Midwestern work ethic," a shirt-off-his-back kind of guy who finishes what he starts and who's usually starting something.

"It's hard not to get excited about whatever Tim is excited about," says Charlie Girsch, another toy inventor who has been a mentor to Kehoe ever since Kehoe stole, and in 1995 married, Girsch's son's girlfriend, Sherri.

Kehoe grew up in a stoic Irish house, but Sherri came from a big, raucous Italian clan. During Kehoe's first Christmas with his future in-laws, the grandmas and cousins and kids all gathered in the living room to play Pictionary. The game was boisterous and hilarious, and Kehoe couldn't believe what a blast he had. That night he left with a new calling-to, as he puts it, "solve the problem of how to have fun."