Is This a Colorfast Fabric and Does It Matter?

Red shirt in white laundry basket

 Victoria Snowber/ Photo Disc/ Getty Images

Learning about colorfastness in clothes is important to your success in doing laundry. Some learn through a terrifying experience of discovering an entire load of white clothes has been turned pink by a red sock. Or, a favorite light yellow blouse has turned green by traveling through the washer with a new pair of blue jeans. Or, unsightly discoloration has appeared on your skin or underwear after wearing new black slacks.

So to help you avoid the shock, it's time to learn what colorfast means and how to be sure you won't have a laundry disaster.

What Is Colorfast? 

Definition: The ability of a fabric or other substances to keep the same color without fading or running even if washed, placed in harsh light, exposed to perspiration or treated with certain chemicals.

The term, colorfast, was first coined in 1916 by the manufacturers of textiles in testing fabrics when exposed to light, washing, perspiration, and abrasion. There are now standards to rate fabric behavior when exposed to testing. The American Association of Textile Chemists and Colorists provides test method development and quality control materials for members in sixty countries throughout the world. Colorfastness during washing is categorized from one to five with the higher number being the better fastness.

Textile chemists and home launderers know that there are many things that can affect whether fabrics retain their color or fade or bleed easily.

  1. Is the fabric colored with a natural dye or synthetic dye?
  2. What is the fiber content of the fabric?
  3. Were the fibers dyed before the weaving or knitting process or was the finished fabric vat-dyed?
  4. What laundry chemicals are used during cleaning (detergent, stain removers, bleach)?
  5. What water temperature is used for washing?
  6. What is the pH of various substances that interact with the fabric (perspiration, detergents, skin creams)?
  7. What dry cleaning solvents are used when cleaning the fabric?
  8. Is the fabric exposed to high drying temperatures?
  9. Is the fabric exposed to harsh light for an extended amount of time?

So, How Do I Know If My Shirt Is Colorfast?

I know all of this is confusing. Why don't they just tell us on the care label if the shirt is colorfast?

Well, clothing manufacturers should tell you if the garment is going to bleed. After all, they are the ones that know how the fabric was dyed. Most don't tell us outright because who wants to buy something that bleeds. But there are hints.

If the label says "wash separately" or "wash with like colors", that usually means that the dye isn't stable and is going to bleed or even rub off. Blue jeans can turn a light colored couch cushion blue because the dye rubs off.

It's even more important to heed the warnings when you have a stain to remove. The chemicals in stain removers are more potent than the detergents used in washing that are diluted in the washer. Obviously, bleaches like chlorine bleach and hydrogen peroxide will remove color. But, other chemicals will remove color as well. That's why you have to test for colorfastness.

Do the Colorfastness Test

One easy way to test if a fabric is colorfast is to dampen a clean, white cloth. Rub the wet cloth on an interior seam or hem of a colored garment. If any color comes off onto the white cloth, then the item is not colorfast and the dye will run when the garment is washed.

For a more thorough test for specific detergents and laundry products:

1. Mix one teaspoon of the laundry product (detergent, stain remover, chlorine bleach, oxygen bleach) with one-half cup of warm water. Stir well to mix and be sure that any powdered formulas are completely dissolved.

2. Turn to an interior seam or hem. If you are concerned that the solution will bleed through to the right side of the fabric, place a dry, white cotton cloth under the test area.

3. Dip a cotton swab in the solution and dab it onto the test area.

4. Blot the area with a white paper towel. If color comes off onto the white paper towel, the fabric will bleed dye. If the color of the test area has changed or become lighter the dye will bleed.

5. If you have a garment with different colors (strips, color-blocks, graphic print), test each colored area separately.

Final Warning

Just because a garment doesn't bleed much the first time it is washed, it may happen the second time through the laundry. Some manufacturers apply finishes to protect fabric surfaces. As they are worn away by abrasion or washing, the dyes can "turn loose" and that's not good.

I Didn't Test and Now I Have a Disaster.

It's happened to everyone. Just follow these tips to remove color bleeding stains.