[iONuClothing]

What is the process or type of printing used on t-shirts where it looks like the ink is dyed into the fabric?

 

[BDM//WHATUP]

That is called "Discharge" I believe.

 

[brent]

Discharge, which can be done "straight" which results in anywhere from an off-white or light tan color to a color halfway between white and the garment's color. You can also add pigment to the discharge, so that the garment's dye is removed and replaced with a new color. Cool stuff.
Also, waterbased inks can settle into the fabric with similar results.