Wednesday, June 10, 2009

Hypercolor T-shirts

I'm not really sure what our reader demographics are like here at the Bayblab, but I'm sure some of you remember Hypercolor T-shirts - the shirts that changed colour with heat. If you ever wondered how that worked, Wikipedia comes to the rescue:

The color change of Hypercolor shirts is based on combination of two colors: the color of the dyed fabric, which remained constant, and the color of the thermochromic dye. The dye is enclosed in microcapsules, tiny (few micrometers in diameter) drops of liquid sealed in a transparent shell, bound to the fibers of the fabric. The liquid is a leuco form of a dye (in this case crystal violet lactone), a weak acid (1,2,3-benzotriazole), and a quaternary ammonium salt of a fatty acid (myristylammonium oleate) dissolved in a solvent (1-dodecanol). At low temperatures, the weak acid forms a colored complex with the leuco dye, interrupting the lactone ring. At high temperatures, above 24-27 °C, the solvent melts and the salt dissociates, reversibly reacts with the weak acid and increases the pH. The pH change leads to closing of the lactone ring of the dye, which then regains its colorless (leuco) form.

Low temperatures allow a weak acid to react with the dye, converting it to its coloured form.

Whatever happened to those shirts anyhow? That they were easily ruined by washing them at higher than recommended temperatures didn't help, but I'm sure it had more to do with people not needing any more attention drawn to overactive armpits.


6 comments:

The Doc said...

I always thought it was cobalt which was responsible for the colour change... although in hindsight, I really never had any evidence to back this up except the pretty pink/blue colour changes.

Unknown said...

So whatever happened to Hypercolor? Where did it go and why?

As with so many great inventions, Hypercolor's downfall came when it tried do too much, too quickly. The beloved t-shirts were a huge success not only in America, but worldwide. Unfortunately, Generra got the bright idea to try releasing other Hypercolor garments in non-US markets. In Japan this was a great success: Hypercolor pants, socks, hats and headbands were very popular. The fatal mistake came when they attempted Hypercolor underwear.

The microencapsulated, thermochromic dye used in Hypercolor garments wasn't able to withstand the constant, elevated temperatures of the average Japanese teenager's crotch. When the 1-dodecanol solvent broke down the myristylammonium oleate salt for an extended period of time, the microcapsules would dissolve under prolonged exposure to the released 1,2,3-benzotriazole. The dye (crystal violet lactone) was then directly exposed to the skin. The result? Blue balls...literally.

Over 400 men were left with permanently Smurfy scrotums and over 220 women were guaranteed that the carpet would never again match the curtains.

The class action suit against Generra forced them out of business. The company was bought by the conglomerate Public Clothing Company in 1993 and all production of Hypercolor merchandise was halted.

Strangely enough, the US government experimented with Hypercolor for several years after it's discontinuation. They wanted to adapt the dye to make uniforms for prisoners and detainees that would help investigators and corrections officers know if a prisoner was lying. Unfortunately, since orange Hypercolor garments turn yellow when they're warm, detainees in Hypercolor prison-orange jumpsuits walked around looking as if they'd pissed themselves. A lawsuit was filed claiming this was abusively humiliating to prisoners, and the program was cancelled.

The US government currently owns the patent for Hypercolor, but there is no information available as to whether or not they plan to use the technology for any future projects.

Rob said...

Informative comment Shauna! A hypercolour headband sounds great. Tell the US government that we all demand one.

Bayman said...

Hypercolor failed because they were F-ing ugly!!! Just like fluorescent pink baseball caps...

Bayman said...

and Vanilla Ice!!!!

Unknown said...

actually, second to the blue ball causing tidy whities, this is my favorite...

http://gizmodo.com/339800/hypercolor-heat+changing-toilet-shows-whos-been-assing-it-up