Because Nomex fabric is flame resistant, the oil and gas industries use it, as well as the military and fire departments. Because the fabric is so resistant to chemicals and heat, you cannot dye it with regular fabric dye. Nomex fabric is similar to nylon because it consists of Kevlar. Acid dye powder dyes Nomex fabric, like nylon.
Scoop out 1/4 oz. of acid powder dye, and put it in a cup.
Add 1 tsp. of water to the cup, and mix it in to the powder to make a paste. If there isn't enough water to dissolve all of the powder, add another teaspoon of water.
Pour 2 1/2 gallons of lukewarm water into your dye pot.
Pour your cup of dye powder paste into the dye pot.
Put your Nomex fabric into the dye pot. Make sure the fabric is fully submerged, and let it soak for 10 minutes.
Heat your dye pot to 120 degrees Fahrenheit, and let the Nomex fabric soak for 10 more minutes.
Add 2 cups of white vinegar to the dye pot.
Stir the dye pot for five minutes, and then only stir the pot every four minutes. Continue this for 30 minutes.
Turn the heat up to 190 degrees Fahrenheit, and keep the fabric in the pot for 30 more minutes, stirring occasionally.
Turn off the heat, and remove the Nomex fabric from the pot.
Rinse the fabric in hot water.
Wash the fabric in warm, soapy water, and rinse it out.
Squeeze a towel around the Nomex fabric to remove excess water.