(Also see About Acid Dyes.)
Leveling Acid dyes are notable for their ability to dye evenly. Use them when you wish to obtain a single solid shade, rather than uneven variations of dark and light. This property is very important when a large project, such as a carpet, could easily show unwanted differences in color from one section to another. They are quite economical: an ounce of dye powder can be used to dye six pounds of wool to a medium shade, for a cost of only one to two dollars (price as obtained from ProChem, assuming a bulk purchase of one pound of each color). Leveling Acid dyes are not usually used for the direct application of dyes, such as dye painting or rainbow dyeing, in which their special strengths are not utilized.
As with all acid dyes, Leveling Acid Dyes are used on animal fibers such as wool, angora, and mohair, in addition to silk and nylon. They should not be used on cellulose fibers such as cotton, nor on synthetics other than nylon. Mohair takes the dye a little more intensely than wool does. Acid dyes are the best choice for dyeing the new fibers Silk Latte, made from milk protein, and Soy Silk, made from soybean protein.
Leveling Acid dyes are not as washfast as other types of acid dyes, because their bonds to the fiber are more easily broken; this property is responsible for their superior levelling properties. ('Levelling,' for a dye, means making a uniform color and intensity of color, by diffusing evenly throughout the material that is being dyed.) Levelling Acid dyes that have bonded to one section of wool can become detached in the dyebath and reattach to another section of wool. (If washfastness is important to you, it is better to use the Lanaset line of protein dyes.) These dyes are quite fast against dry cleaning, however; dry cleaning is recommended for items that have been dyed with levelling acid dyes.
Looking at the washfastness numbers on the Lightfastness page, you might imagine that the Leveling Acid dyes are really quite washfast, because the number given for most Levelling Acid dyes for washfastness is a quite respectable 5 out of 5. Does this mean that it is as washfast as fiber reactive dyes that have washfastness ratings of 5? Unfortunately, no. The standard for washfastness for acid dyes is on a far more lenient scale than that for other dyes, because the assumption is that woolen garments will be hand-washed in cool water, or dry-cleaned. The test used for acid dyes is a very moderate 105°F washing—washing in cool water, that is, 40°C—which is far gentler and kinder to the dye than any hotter wash. In contrast, the ratings for the Lanaset dyes is based on a 140°F wash; they are much more washfast than the Levelling acid dyes. If you subject a fiber-reactive dye to a boiling bath, the dye will remain attached; boiling will remove most acid dyes, but then, that hardly matters, since boiling will completely ruin most wool garments.
Kiton is a name used to describe the Levelling Acid dyes, because it is the name under which Ciba first sold this series of dyes. Although the name remains useful, the word Kiton has not been used by the manufacturers since the early 1970s, when Ciba merged with Geigy, after which their acid leveling dyes were sold under the name Erio. Other brand names under which this class of dyes are or have been manufactured include Intracid, Sandolan, Amacid, Techtilon, Dyacid, Permalon, and Orcoacid. Levelling Acid dyes can be purchased in large quantities from many different suppliers to the textile industry. They may be purchased in much more manageable small quantities as Kiton Acid Dyes from PRO Chemical & Dye in the US (they do ship internationally), as Cushing Perfection Acid Dyes, as Landscapes Dyes of Australia (with acid already added to the dye powder mixture) from various retailers such as Kraftkolour in Australia and Woodland Woolworks in the US, and as Dyacid dyes from Kemtex Educational Supplies in the UK.
|name||ProChem's name||Colour Index Name||Colour Index Number||notes|
|Fast Yellow||CK117 Sun Yellow||Acid Yellow 17||C.I. 18835|| 'azo dyestuff' |
2,5-dichloro-4- [4,5-dihydro-3-methyl-5-oxo-4- [(4-sulfophenyl)azo]-1H- pyrazol-1-yl]benzenesulfonic acid, disodium salt
|Azophloxine||CK301 Basic Red||Acid Red 1||C.I. 18050|| 'monazo dye'|
5-(acetylamino)- 4-hydroxy-3- (phenylazo)-2,7- Naphthalenedisulfonic acid, disodium salt
|Fuchsine 6B||CK307 Bright Blue Red||Acid Violet 7||C.I. 18055||'monoazo'
5-(acetylamino)- 3-[[4- (acetylamino)phenyl]azo]- 4-hydroxy- 2,7-Naphthalene disulfonic acid, disodium salt
|Erioglaucine||CK409 Turquoise||Acid Blue 9||C.I. 42090||'triphenylmethane'|
also known as D and C Blue No. 4
noted for poor lightfastness
Ammonium, ethyl(4-(p-(ethyl (m-sulfobenzyl) amino)- alpha- (o-sulfophenyl) benzylidene)-2,5-cyclohexadien- 1-ylidene)(m-sulfobenzyl)-, hydroxide, inner salt, diammonium salt
|Alizarin Blue||CK440 Bright Blue||Acid Blue 40||C.I. 62125||molecular structure
4-[[4-(acetylamino) phenyl]amino]- 1-amino- 9,10-dihydro- 9,10-dioxo-2- Anthracenesulfonic acid, monosodium salt
maximum absorption 610 nm
|Alizarin Saphirol B||CK445 National Blue||Acid Blue 45||C.I. 63010||molecular structure
4,8-Diamino- 1,5-dihydroxyanthraquinone -2,6-disulfonic acid, disodium salt
|Palatine Fast Black WAN||CK605 Carbon Black||Acid Black 52||C.I. 15711||'chromium metallized azo dye' (trivalent chromium)
According to Linda Knutson's Synthetic Dyes for Natural Fibers, Acid Levelling dyes are commonly used as the acid dye components in the dye mixtures that make up All-purpose dyes. Unfortunately, since the ingredient lists do not indicate the contents of all-purpose dyes, we have no idea which dyes are found in which color mixtures.
In the UK, Kemtex carries a line of acid levelling dyes called Dyacid, available in quantities as small as 25 grams per package. Colors include Daffodil Yellow 2G, Rose 2G, Brilliant Pink 4B, Royal Blue AG, Emerald Green AG, Nigrosine GS, and Black 10B.
Landscapes of Australia is another line of Levelling Acid dyes. (Reference: Woodland Woolworks (PDF). A wide range of colors is available, but no information about which colors contain which dyes, or which colors are unmixed and therefore best for use as mixing primaries. The acid auxilliary required is already mixed into the dye mixture, which further simplifies the already simple recipe for using the dye, inevitably at a significant added cost.
Cushing Perfection Acid Dyes are all blends of acid levelling dyes. They are designed to be used as packaged, without blending your own colors. Their colors have been designed to remain stable over time, so that a dye purchased today will produce the same color as the same dye name originally mixed by Wainwright Cushing. If you wish to mix your own Cushing Acid dyes, their best colors to use as mixing primaries are (light) Canary, Cherry and Peacock, and (dark) Yellow, Blue and American Beauty.
Acid Levelling dyes are popular in the textile industry for dyeing carpet yarns, woolens and worsteds for clothing, and tightly woven fabrics such as gabardines. The following list includes the Color Index names for the other acid levelling dyes I have seen listed:
A few of the dyes classified in the list above as Levelling Acid dyes can be found among other lines of dye. In the Jacquard Acid Dye line, you can find Acid Yellow 49 (601 Yellow Sun), Acid Yellow 219 (603 Golden Yellow), Acid Red 52 (620 Hot Fuchsia), Acid Red 266 (617 Cherry Red), Acid Blue 7 (624 Turquoise), Acid Blue 62 (623 Brilliant Blue), and Acid Green 25 (631 Teal).
Among PRO Chemical & Dye's Washfast Acid Dye line, you can find Acid Red 52 (WF370 Rhodamine Red), Acid Red 266 (WF366 Red), Acid Violet 17 (WF817 Brilliant Violet), Acid Blue 7 (WF478 Turquoise), Acid Blue 40 (WF440 Bright Blue) [is this the same as CK440?], and Acid Green 25 (WF725 Forest Green).
Levelling acid dyes require more acid than other classes of acid dyes. For this reason they are sometimes described as the 'Strong Acid Dyes'. The pH for dyeing with Levelling Acid dyes should be lower than for Washfast Acid Dyes or Lanaset dyes; different sources indicate that it should be in the range 2.5 to 3.5, or in the range 3.5 to 4.5. Recipes vary, but here is a brief summary of one that is fairly representative: for one pound of wool, combine two teaspoons of dye powder with a small amount of water to make a paste, then add to two gallons of lukewarm water in a non-reactive dyepot, along with salt and a small amount of Synthrapol. Add prewetted wool and soak for ten minutes, then gradually heat on a low setting until warm, about 120°F. Add acid (white vinegar, sodium bisulfate, or citric acid), and heat slowly to boiling or almost boiling, at least 185°F, then hold that temperature for 30 to 60 minutes. Allow the fiber to cool before washing out.
Follow the instructions provided by your dye supplier, or choose one of the detailed recipes whose links are listed below.
Although it makes more sense to use less level dyes in doing rainbow dyeing, it is possible to do rainbow dyeing with Kiton Acid Levelling dyes; see the instructions in the links below:
Avoid enthusiastic stirring and rapid temperature changes, as these tend to cause felting. If dyeing is not sufficiently level, you can repeat the process by immersing the dye in a water bath with acid, using a larger amount of acid than you used the first time, gradually warming the wool in the dyebath as before, and boiling for 30 minutes. The dye will come off of the fiber in the boiling water bath, and redeposit on the fiber.
Almost any color can be mixed by combining just three Acid Levelling dye colors, yellow, blue, and red, in varying proportions. PRO Chemical & Dye says that the best colors for mixing a wide range of colors are Sun Yellow CK117, Basic Red CK301, and Bright Blue CK440.
Nothing can substitute for making your own series of test swatchs with small amounts of dye to see which mixtures produce which colors; keep careful records of how many grams of each dye it takes to dye a swatch of a certain weight, so that you will be able to reproduce colors in the future.
If your goal is to make "natural" looking colors, a good move is to prepare a "toning" mixture of grey or brown, by mixing all three primary colors until the color suits your needs, and then use this mixture to add to other colors as you mix them.
2. David M. Lewis's Wool Dyeing is far more technical and contains a lot of information from chemistry and the textile industry. He distinguishes between the monosulfonated and disulfonated subdivisions of what he refers to as Level-dyeing or Equalising dyes. (Order Wool Dyeing directly from the Society of Dyers and Colourists in the UK for £35 plus shipping, which is, at this writing, only a little more than a quarter the cost of a used copy from Amazon in the US.)
3. Wilfred Ingamells's Colour for Textiles, a User's Handbook is another technical manual; it refers to these dyes as Equalising acid dyes.
I do not know of any book that shows illustrations of examples of articles or swatches dyed with Acid Levelling dyes; please let me know if you do. Most books showing color mixing in acid dyes use Lanaset dyes or Washfast Acid dyes.
All of the pages on this site are copyright ©1998‑2021 Paula E. Burch, Ph.D.
Last updated: January 5, 2010
Page created: December 31, 2006
Downloaded: Tuesday, June 22, 2021