How can i improve fastness properties of nylon dyeing?

Answer 1

Start by soaking your nylon in a mixture of 50 percent water and 50 percent distilled vinegar for at least a half-hour. Then use a pure acid dye according to the instructions that come with it.

There are two kinds of dyes: acid dyes and fiber reactive dyes. Fiber reactive dyes won't stick to nylon. Acid dyes will. Now, when you buy a box of Rit dye you are getting half a box of fiber reactive dye and half a box of acid dye - this helps them ensure that the thing you are dyeing will turn color. Problem is, the half a box of reactive dye doesn't do anything to the nylon, so half your money is going down the drain unused. There are a lot of places online that have the right dyes for you.