The application of a foundational substance, mordant, or base dye to a fabric or yarn to prepare it for the primary coloring process. This base layer ensures the final dye strikes evenly and achieves the correct depth of shade, especially when dyeing difficult fibers or aiming for dark, complex colors.
Heard on the job
We're bottoming the cotton warp with a light yellow before running it through the indigo vat to get that specific green cast.