Sciencemadness Discussion Board

colorfast black dye for cotton

xxxxx - 22-2-2007 at 15:51

with the development of the brightly hued dyes, such as turquois it would seem that there should be a colorfast black dye for cotton. however, upon sufficent exposure to sunlight most cotton dyes discolor to green or orange. what is the reason that a colorfast black dye for cotton has not been developed yet?

Ozone - 22-2-2007 at 20:58

"black" is a mixture of several dyes (try mixing some with MeOH and chromatographing it with a coffee filter). The blue dye goes (is degraded) first on exposure to UV light (rendering it soluble--or it reacts). Washing removes this part revealing the other parts, which tend to be green or orangish-red (the color balence of black).

one scenario,

O3

YT2095 - 23-2-2007 at 02:09

I`ve had reasonable success using a KmNO4 soln with Wool to make Black, a Pure Black.
it doesn`t wash out or fade either, Perhaps it may work with cotton also?

be carefull not to make soln Too strong because it will denature the material somewhat.

Mumbles - 24-2-2007 at 22:20

I've only been able to get brown from permanganate, though never intentionally. I want to say iodine maybe would be able to give a black, or at least the illusion of black. Most of my suggestions won't be very organic based. Lampblack seems to stain everything, I imagine a slurry of it in say sodium hydroxide or HCl might be able to dye some wool or cloth.

You could always rub tar on the shirt :D



On a totally unrelated note. I feels good to be back around the forum.

YT2095 - 25-2-2007 at 04:33

it`s quite possible it`s the Amine content in the wool, that makes it work so well, cotton on the other hand wouldn`t have so much of this being Plant based as opposed to Animal.

it was worth a try anyway :)

nightowl52 - 18-3-2018 at 14:06

you need carbon black made to a dye i make carbon black mulch colourant waterbased lasts for 2 years on mulch in the weather in australia