What is the flowy poly fleece method in tie dye?

This is a technique I call the poly fleece method, for ice dye. It's a trick I developed while chasing the watercolor look on thinner fabrics.

I first noticed that thick sweatshirts hold their folds with structure, creating smoother dye flow, while light shirts crinkled and broke the color lines.

I tried foil supports, but the sharp points disrupted the flow.

Then I stacked multiple cotton shirts, hoping they’d mimic sweatshirt weight, but each layer absorbed instead of channeling the dye.

Eventually I used a layer of polyester fleece beneath the thin shirt.

It repelled just enough moisture to keep the dye traveling across the surface instead of through it, while still allowing gentle drainage.

The result is what I now call flowy ice dye. Long, smooth gradients that behave more like watercolor art than traditional tie-dye.