Category Archives: dyeing protein fibers

Why won’t my wool take up dye?

Hi, I have a question for you. I’ve been a dyer for many years. I dye all sorts of fibers and use synthetic dyes and natural dyes, ecoprinting etc my question is this: why won’t my wool take up dye? I have had this happen one other time in the past with a batch of wool top that I purchased and it has now happened again. I was trying to dye this wool with coreopsis. I washed the wool with a textile detergent and rinsed. Then I mordanted with alum and cream of tartar. i then put it in my dyebath and even adjusted the ph to an alkaline solution. the dye bath was a deep brown red as it should have been but after simmering, stopping the wool had only a tiny shift of color change to offwhite. I repeated the process and nothing. Could this wool have been processed with a chemical that i was unable to remove in the washing stage? I’m totally confused here. thanks for any feedback, Juli

So far, every time, the answer to this question has always been that the fiber was mislabeled as wool, when it was actually a synthetic fiber, such as acrylic. Have you used this exact same dyeing procedure in the past with success?

If you take a little bit of the fiber and burn it, does the burned fiber char, or does it melt? I like this Fiber Identification Burn Chart at Ditzy Prints:
Ditzy Prints Burn Chart for Fiber Identification
If you still have your dyebath, please try some samples of other wool that you may have to see if it takes up more color.

It is surprising how processed wool can be, and yet continue to dye very well. For example, Superwash wool is processed by being chlorinated and then treated with a sort of plastic, a polymer resin called Hercosett 125, that glues down the scales that are found on the surface of mammalian hairs (like the scales on our own hair); this enables the wool fibers to be treated roughly without interlocking, shrinking, and felting.

You would imagine that such dramatic treatment would interfere with dyeability, wouldn’t you? And yet Superwash wool is excellent for hand dyeing, no problem at all. In fact the processing has obvious benefits in preventing felting or shrinkage, when that’s important.

Please let me know if this makes sense, from your observations.

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


Are Dharma Acid Dyes grouped as warm versus cold colours? Which are the best to start with?

Name: Rebekka
Country_or_region: UK
Message: Thank you for your website. I have a question concerning Dharma Acid Dyes. They have several primary colours. Do you know if they group them in warm and cold colours as Jacquard does? Which ones are the best to start with?

Best wishes,

Warm colors are those with red in them, while cool colors are those with blue in them. A very pure cyan, magenta, or yellow can be used equally well to mix either warm or cool colors. This is why printers can produce any hue by combining just cyan, magenta, and clear yellow, plus black for darker shades.

If a dye’s color is not a pure enough cyan or magenta or clear yellow, however, it cannot be used to produce all hues. If a blue is more indigo than cyan, it will work well for mixing purples, but poorly for mixing greens. A greenish cyan will be good for mixing greens, but if used to mix indigo blue or purple, it will produce a duller, darker color. A red that is on the yellow side of magenta is great for mixing orange, but the purples it produces in mixtures will be brownish, while a blueish red is wonderful for mixing purples but poor for mixing oranges. A yellow that has too much orange in it cannot be used to mix a pure aqua green, but it works well for more olive-toned greens. This means that, if there is no dye in a particular line of dyes that is a pure printer’s primary, one must obtain both cool and warm versions of each of the three primaries, in order to be able to mix every color.

In addition, dyes have other characteristics that vary, such as how quickly they spread on the fiber before bonding to it. This is inconsequential when one is dyeing solid colors, but can be crucial when the dye is applied directly to the fiber. If it is important that a dye mixture stay together as a single color when painted directly on the fiber it’s being used to dye, then other mixing primaries may be selected whose properties are more similar to one another.

I would recommend that you start with Dharma’s 401 Brilliant Yellow (for both warm and cool), 402 Fire Engine Red (warm), 411 Deep Magenta (cool), either 404 Sapphire Blue or 409 Dark Navy (warm), and 407 Caribbean Blue (cool). You may also want 413 True Black. Other people might recommend a slightly different list, for starting out.

Dharma lists the following dyes as their primary (mixing) colors among their Dharma Acid Dyes:

Warm Primaries:
414 Sunflower
M acid yellow 135 [also sold elsewhere as ProChem yellow]
401 Brilliant
M acid yellow 19 [also sold elsewhere as Jacquard 602 bright yellow and as ProChem WFA Sun Yellow 119]
402 Fire Engine Red L acid red 266 [also sold elsewhere as Jacquard 617 cherry red and ProChem WFA Red 366]

404 Sapphire Blue L acid blue 25 [also sold elsewhere as ProChem WFA National Blue 425c]
409 Dark Navy M acid blue 113 [also sold elsewhere as ProChem WFA Navy 413]
415 Midnight Blue L acid blue 92
Cool Primaries:
401 Brilliant
M acid yellow 19 [also sold elsewhere as ProChem WFA Sun Yellow 119]
445 Fluorescent
L acid yellow 250
411 Deep Magenta M acid red 131 [also sold elsewhere as ProChem WFA Polar Red 390]
406 Fluorescent
L acid red 52 [also sold elsewhere as Jacquard hot fuchsia 620 and ProChem WFA Rhodamine Red 370]

407 Caribbean
L acid blue 7 [also sold elsewhere as Jacquard 624 Turquoise and ProChem WFA Turquoise 478]
416 Peacock Blue L acid blue 40 [also sold elsewhere as ProChem WFA 440 Bright Blue]

Dharma also lists their 413 True Black as a mixing primary; obviously, black is not a true primary color, but many people use it for mixing darker, duller shades of other colors.

Note that 401 Brilliant Yellow is listed under both warm and cool mixing primaries. This means that it is a very clear, pure yellow, which can be used whether you wish to mix it with reds (for warm colors) or blues (for cool colors). This makes it a particularly good choice to start with.

It’s really a judgment call in some cases, a matter of taste, which you prefer. It’s interesting to compare what different dye suppliers recommend. While Dharma lists their 407 Caribbean Blue as a cool blue primary, Jacquard lists this same dye (acid blue 7) as their warm blue primary 624 turquoise. You can use it as either a warm or a cool mixing primary. Dharma’s 406 fluorescent fuchsia is listed as a cool red mixing primary, but, while Jacquard does sell this dye (acid red 52), they don’t list it as a mixing primary at all, but instead recommend recommend their 618 fire red (a mixture of acid dyes) as their cool red mixing primary; they don’t carry the same dye as Dharma’s 411 Deep Magenta.

Another way to get an idea of which dyes in a particular dye line are considered by many people as the best colors to start with, for mixing, is to look at which dyes are included in their starter kits. PRO Chemical & Dye’s Washfast Acid dye line has some overlap with some of the Dharma Acid Dyes. In their Warm Palette acid dye sampler, they use acid yellow 199, acid red 151, and acid blue 25. This last dye, acid blue 25, is sold by ProChem as National Blue, and by Dharma as sapphire blue. In their Cool Palette acid dye sampler, ProChem includes acid yellow 19, which is the same dye Dharma sells as 401 Brilliant Yellow, acid red 138, and acid blue 90.

Whether to choose fluorescent dyes is another question. Fluorescent dyes are brighter than any others, because they gather ultraviolet light that is invisible to our eyes, and release it as visible light, resulting ina brighter-than-bright effect. Whenever there is a source of ultraviolet light, such as sunlight, or a blacklight, or some fluorescent lights, a fluorescent dye, such as Dharma’s 445 Fluorescent Lemon or 406 Fluorescent Fuchsia, will appear to be exceptionally bright. It will seem less so under a low-ultraviolet light (such as firelight or incandescent lightbulbs). Fluorescent dyes tend to fade faster as the result of light exposure than other dyes, because of the added energy of the ultraviolet light that they absorb, so they are not the best choice for art that is expected to maintain its color unchanged for many years. For archival purposes, it is better to chose more lightfast colors such as Dharma’s 401 Brilliant Yellow instead of 445 Fluorescent yellow, and 411 Deep Magenta instead of 406 Fluorescent Fuchsia, but when the goal is to wow people with exceptionally sharp, bright colors, if longevity is not an issue, the two fluorescent dyes are preferable.

Acid dyes tend to be better at either leveling to make a very smooth solid shade, or at washfastness, but not both (ignoring the existence of reactive dyes such as those in the Lanaset dye line). A highly washfast color is harder to get perfectly level in color, but it does not fade as quickly in the wash. A highly level color is less washfast, though of course this varies according to dyeing technique; typically it is best to dry-clean clothing that has been dye with acid leveling dyes, rather than washing it. Dharma marks their acid leveling dyes, in the dye chart on their Instructions tab, with an “L” for “Leveling”, and their acid milling dyes with an “M”. You can mix the acid leveling dyes and acid milling dyes that Dharma sells, but if you are very concerned with leveling or with washfastness, you will want to look into this further. You can get more information about acid dyes on my website; see “About Acid Dyes”, “Leveling Acid Dyes”, and my page about Washfast Acid dyes.

There is a great deal of important information in the “Instructions” tab on Dharma’s Acid Dyes page. I strongly advise everyone to study this information closely before using the acid dyes.

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


Once thin silk takes one color of dye can it be overdyed a darker color?

I recently dyed some pieces of silk and gauze. Once the silk takes one color of dye can it be overdyed a darker color? The colors I got were not what I expected. In one a green color took over the piece. I have tried over dying the green with cobalt and it’s not doing anything. I would love any advice you have to offer.

Thin silk is limited, as you’ve seen, in how many dye molecules it can take up. While thicker fabrics such as a heavy raw silk, or the cotton jersey of t-shirts, can add more color through six or more rounds of dyeing, a very thin sheer fabric, such as chiffon or gauze, may do so through only one or two rounds of dyeing, refusing to change color further when you dye it again.

Physical manipulation of the fabric, as by rough washing, can free up more dye sites in a fabric, but that’s not a good idea with fine silks.

Removing the dye color with a dye discharge chemical, such as thiox, will probably not help, because the dye molecules will still be bound to the fabric even after they have been decolorized by the reducing agent. The hypochlorite in chlorine bleach might chew up enough of the surface of the fabric to reveal more dye sites, if you’re dyeing cotton gauze, but you should never use chlorine bleach on silk, since it is very destructive to protein fibers.

You might be able to add another layer of color if you use an entirely different class of dye which attaches to the molecules of the fabric in a different way. For example, if you have been dyeing your silk with Procion dyes plus soda ash, you might find that dyeing them with acid dye plus an acid, such as vinegar, will allow one more round of color—or if you’ve been using acid dyes, which includes Procion dyes that have been set with an acid rather than soda ash, then you might try dyeing with Procion or another fiber reactive dye, and setting it with soda ash. Definitely a matter of trial and error, no guarantees that it will work, but it is worth experimenting.

Also see my earlier post, “Will a fabric reach a saturation point after which it cannot take any more dye, or any more dye of a given colour?“.

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