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Extracting Dyes


Ganoderma

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a new hobby of mine :)

 

I am wondering though, i am wanting to try some of the dye on clothing, but not have it go into the water and dye everything else when washed.

 

 

would a good basic step be first to wash the dried plant material with water to get all the water soluble stuff out? then continue with extracting the other things. does that seem right?

 

also, with the water soluble colours, is there are relatively easy (as in cheap) way to make them not so water soluble?

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a new hobby of mine :)

 

I am wondering though, i am wanting to try some of the dye on clothing, but not have it go into the water and dye everything else when washed.

 

 

would a good basic step be first to wash the dried plant material with water to get all the water soluble stuff out? then continue with extracting the other things. does that seem right?

 

also, with the water soluble colours, is there are relatively easy (as in cheap) way to make them not so water soluble?

 

Follow along. ;)

 

http://hypography.com/forums/chemistry/2357-chemistry-of-paint-and-pigments-12.html

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Dye that binds to cloth only by adsorption will not be washfast. The equilibrium is dynamic and goes in both directions. You need a dye that covalently bonds and is therefore irreversibly bound. The oldest way to do this is with mordants.

 

Take your undyed cloth, saturate it with a dilute solution of alum, chrome alum, (reduced) chromium sulfate, or iron ammonium sulfate. Wring out well, then plunge into a solution of washing soda (wear gloves). Hydroxide gels of aluminum, chromium, or iron precipitate and bind within the fibers. Wringm out and immediately plunge into the dye solution. Hydroxide gels strongly bind the dyes (often with color change). Wring out and let dry, then warm and dry. The gels dehydrate into refractory oxides that permanently bind the dyes and that to the fibers. Wash alone once or twice to get out the loose stuff.

 

A second possibilty is vat dyes. Oxidized dyes that are water-insoluble (indigo) often reversibly form water-soluble (uncolored) reduced species. Thus macerated indigo plant is allowed to anaerobically ferment. Cloth is plunged into the reduced odorous muck and wrung out. As the wet cloth hits the air it turns that wonderful indigo blue by reaction with oxygen. Indigo is washfast but not lightfast. Wash once or twice to get out the loose stuff. Red beet juice is the elegant molecule betanidine, remarkably strongly bound by mordants.

 

Oregon-grape - Wikipedia, the free encyclopedia

The inner bark and roots have yellow berberine with an unusual molecular structure.

 

Modern methods are fiber-reactive dyes - Procion, Cibacron, Remazole - and disperse dyes for plastic fibers (polyester). Foron Brillant Blue into polyester is INSANELY blue. Black umbrellas are aniline black formed by polymerizing the dye directily within the fiber.

 

"Color Chemistry" by Heinrich Zollinger is a good read.

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