Category Archives: vat dyes

Pre-reduced indigo: natural versus synthetic

Name: Jen

Country or region: US

Message: I’m doing research on pre-reduced indigo crystals. I’m finding that they’re being called everything from freeze-dried to instant and claims of them being ‘natural’, extract, etc. This flies in the face of what I’ve also been told directly by an importer- if it comes from India it’s all synthetic. Even the stuff one seller is claiming produced in Japan has an import label from India! So you can see confusion.
Any information or insight you’d be nice enough to share is most appreciated.

Hi Jen,

I believe that I’ve NEVER encountered pre-reduced indigo that was not synthetic. Those who wish to use only plant-derived indigo must do more work to reduce their indigo themselves.

I suspect that there is no difference at all between pre-reduced indigos that are listed as being freeze-dried, dried, or instant, merely different ways of describing the same product. Indigo “extracts” appear always to be the normal oxidized form which must be reduced by the dyer before use. Note that pre-reduced indigo is not 100% reduced; the various retailers all specify that their pre-reduced indigo is 60% reduced. The remaining 40%, which is in the oxidized form, is unusable unless the dyer chemically reduces it in the indigo dyeing vat. (Both synthetic indigo vats and natural fermentation indigo vats produce chemical reduction.)

Often a retailer’s advertising copy reads as though their pre-reduced indigo is natural, but if they are both reputable and careful you can see that it is not. For example, Dharma Trading Company, which is good about what claims they make, says:

As an alternative, try this Pre-reduced Indigo. Synthetic Indigo (chemically identical to natural Indigo) has been pre-reduced chemically, then dried, so it dissolves in water right off the bat….This all makes it have a lower environmental impact for the dyer than taking the original natural or synthetic Indigo from start to finish with all the chemicals involved.
(source)

Jacquard Products starts off saying “This natural vat dye exists in plants all over the world”, but concludes clearly with “Jacquard’s indigo is a synthetic organic and comes pre-reduced 60% for unprecedented ease of use.” (source)

“Organic” is a difficult word for the dyer, because an organic chemical is any chemical that contains carbon; it has nothing to do with organic farming. All dyes, whether natural or synthetic, are organic chemicals, aside from a few mineral colors that are not really of interest. However, many dyers mistake claims that a dye is organic, thinking it means it is a plant-derived dye when in fact it is not. Dye sellers sometimes purposefully exploit this confusion.

Jacquard pre-reduced indigo is available through Amazon, as well as other sources; a supplier on Amazon currently selling Jacquard pre-reduced indigo, “The BT Group”, provides misleading information claiming that what they are selling is naturally occurring. There’s an issue with resellers on Amazon, which can post wrong information about their products; it’s likely that The BT Group doesn’t know anything about what they are selling, and merely selected several phrases from the Jacquard copy without paying attention to how they have changed the meaning by omitting a key word. Similarly, Etsy sellers give blatantly false information about whether the pre-reduced indigo dye they sell is from natural sources, when what they are selling is obviously synthetic, given their suppliers.

Earth Guild makes an error, showing instructions for using natural indigo on a page whose title is “PRE-REDUCED INDIGO INSTRUCTIONS”, but I don’t think that the title of a web page amounts to a claim, given that many people who edit web pages don’t even know how to alter the titles of their pages. (source) In corroboration of this interpretation, they have a page on Lanaset dyes with this same webpage title, so it’s just a mistake.

George Weil helpfully says that pre-reduced indigo is used as “an alternative to Natural Indigo”. (source)

There are blogs that have instructions for using pre-reduced indigo which assert that the dye is natural, but in every case it seems that the blogger was insufficiently knowledgeable. Since they’re not selling the dye, they’re not legally liable for their claims in the same way that someone who is selling a pre-reduced indigo is.

If you find any additional information, I will be interested in learning about it!

(Please help support this web site. Thank you.)

Paula

Where can we order Vat dyes in Germany?

Name: Karin
Country or region: Germany
Message: Hello and sorry for disturbing, we want to order Vat Dyes and didn’t know where. Can you help us?
Thanks and best regards
Karin

Hi Karen,

Vat dyes are not as difficult to find as Naphthol dyes (yesterday’s question). A good retail source for vat dyes in Europe is Granat Farvekompagniet in Denmark. Look for their page of Granat Kypefarver/Batikfarver.

Vat dyes are widely available in many countries, including countries in Africa in which other classes of dye can be difficult to find. North American dyesellers from which vat dyes can be ordered include Aljo Manufacturing, PRO Chemical & Dye, and Maiwa Handprints. In Australia, Batik Oetoro sells Indanthren Vat dyes. (More information for each of these companies is available on my page, Sources for Dyeing Supplies Around the World.)

Vat dyes are not as suitable for beginners as Fiber Reactive dyes, but they are neither difficult nor dangerous to use, assuming normal safety precautions with safety goggles and gloves. The dyes are usually purchased in an insoluble oxidized form, and must be chemically reduced in order to solubilize them and get them inside the textile fiber; when the fiber is then exposed to air again, the dyes re-oxidize and become insoluble, so that the dye inside the fiber becomes fixed in place.

Vat dyes are particularly interesting for printing on fabric that has been dyed with dischargeable dyes, such as Remazol dyes or most Procion dyes. The same chemicals that are used to solubilize and reduce the vat dye will remove the existing color from the dye on the fabric, allowing the brightness of the vat dye in your design to contrast sharply with the background color. Granat Kypefarver/Batikfarver’s range of Vat dyes has been especially selected for being suitable for illumination dyeing on backgrounds made with Fiber Reactive dye.

Another useful property of Vat dyes is that most of them are less susceptible to fading than other types of dye. Not all Vat dyes are equally light resistant, but many are significantly more light-resistant than Fiber Reactive dyes or Direct dyes.

A specialized category of Vat dyes is light-sensitive pre-reduced Vat dye, which can be used to make single-color photographic prints on fabric. There are two brands of this amazing product available, with slightly different colors. Jacquard Products makes SolarFast light sensitive dyes, in fourteen different colors, and Lumi makes Inkodye, available in nine colors. Unlike sun-printed fabric paints such as Setacolor, the light-sensitive dye does not change the feel of the fabric, and it wears better than fabric paint since the dye penetrates the fiber. Since it is actually visible light that fixes the dye, rather than the heat from the infrared in sunlight as for fabric paints, inkjet transparencies with photographs or drawings can be used to make quite detailed designs.

For more information about Vat dyes and their use, see my page “About Vat Dyes”.

(Please help support this web site. Thank you.)

Paula