When I was in sixth grade or so, apparel with color changing properties was popular… for all of about five minutes. The way this worked is the color would change based on body heat, so areas where your skin was in direct content with the fabric would turn a different color than those areas that weren’t. You can imagine how interested and potentially disgusting this could be. These “mood outfits” quickly went away, thankfully like most things popular in the 80’s, but they seem to have spawned something interesting, but in a bad way.
Enter Sweat Activated Technology. This method of printing evidently keeps your logo, phrase or whatever invisible until, you guessed it, you sweat all over it.
Seems to me there might be a better application for this, maybe cloth baby diapers or seafaring baggage. I can imagine this being helpful as a marker for sensitive water-intolerant equipment packaging or as a gauge for a moisture-attracting koozie. What I can’t imagine is anyone actually wanting a shirt that allows you to frame your perspiration with a company logo or slogan. “Boy, you sweat alot, I can see your entire logo,” would be a nightmare phrase to hear in my opinion.
So while many advances in printing technology can evoke creativity in designers, I would have to file this one next to scratch and sniff catbox liners.