>> reporter: today, diapers are about half as bulky. that didn't happen by accident. diaper companies spend millions of dollars every year to try to make diapers thinner, more absorbent. we were granted access to pampers' never before seen research and development center. where over 500 scientists, chemical engineers, and seamstresses are trying to improve the look and the feel of the nappy. >> okay, i can't even say that. >> that's the analytical chromatography lab. >> okay. >> reporter: their work is surprisingly top secret. no one, not even executives like terry halley, have access to every room. here, they're working on prototypes for new diapers. they are tested for scent, touch, flexibility, and durability. >> we want to make sure that as babies, they're scooting around on their bottom, and moving, that that product stays together and stays as intended the entire wear time. >> 23.4 pounds. >> yeah! >> good boy. >> good job!