Is Borax color-safe?

You’d think this would be easy to find on-line, but dang it…! Ambiguity abounds!

Can I use Borax on colored clothes without the risk of fading the colors?

Circle one:…YUP…NOPE

Depending on the material of the clothes, and the dye(s) used, any detergent has the capability of causing some degree of fading. The only thing to do to be sure is to test it on a part of the material that would normally be hidden while wearing the item. Make a thick paste of the detergent in question by mixing a small quantity with a few drops of water, and apply to a small spot on the aforementioned hidden area, and give it, say, 12-24 hours to sit, then rinse thoroughly. If you can’t see any fading, you can assume the color will be safe under normal washing conditions.

I did circle one, and now I have a Sharpie mark on my monitor. Thanks.

FTR, what I see seems to indicate that Borax will work with colours. However, I too would defer to someone with practicle knowledge of the subject.

But Borax doesn’t use an oxygen reaction and doesn’t “bleach”, right? This is what’s unclear to me.

A red t-shirt may fade a bit and not be as deepand vibrant a red, but Borax won’t turn it pink will it?

Oh, no, not as far as I’ve noticed. If some fading is tolerable, you should be fine. Its bleaching action occurs through the production of a weak hydrogen peroxide solution, which isn’t as strong a bleach as sodium hypoclorite (as in Clorox). Nevertheless, it might be advisable to test it as above, especially if you’re concerned about an expensive article of clothing. Some information on the chemistry of borax as a cleaning agent here:

So from your quote, it looks like Borax is most effective when it’s used with other detergents. Interesting.

Related question: What exactly do detergents do, anway?

There are two main cleaning agents used in laundry soap. Detergents break down surface tension in water, allowing it to more thoroughly wet fabrics, particularly synthetics. Surfactants are emulsifiers, which cause dirt and oil to be suspended in the water, rather than redepositing on clothes.

Laundry chemistry 101.

Borax (sodium tetra borate) is a water softener. It binds to (chelates) the calcium, iron, or other metal ions in hard water that would otherwise bind to, and render ineffective, the anionic (negatively charged) detergents and surfactants in your laundry soap. Borax is not a detergent, surfactant, or bleaching agent. It merely increases the effectiveness of the detergents and surfactants in your laundry soap. Under normal circumstances, it will not cause fading.

What Squink said, except, I’ll add, Borax is, from practical experience, also pretty abrasive. It doesn’t desolve well in cold water. The abrasive action can cause fading from wear.
I put it in my carpet to kill fleas, and use blueing to brighten my laundry.