Sweat-activated t-shirts

The message is screen printed in a clear, water-repellent ink. On a dry shirt it is practically invisible, so the tee reads as plain heather grey.

When you sweat, the cotton around the print soaks up moisture and turns darker. The printed letters repel water and stay light, so the line appears against the darker fabric, right where you sweat first: the chest and the collar.

As the shirt dries, the line fades back into the fabric. Rain or a splash of water works the same way as sweat.

Sweat reveal only works on fabric that visibly darkens when wet, which is why the sweat line uses heather grey and blue heather cotton-poly. White and black tees barely change colour, so a hidden message would stay hidden.

We also avoid silicone softener finishes on our blanks, because they make the whole shirt repel water and weaken the effect.