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Heinz Distilled White Vinegar 16 oz
contains 5% acetic acid in water
Shibori: Creating Color and Texture On Silk
by Karren Brito
includes instructions for using sodium acetate with acetic acid to make a buffered dyebath
Vinegar is a mild acid, the most commonly available household acid. While vinegar can be made from many different sources, such as apple cider, malt, wine, and so on, the purest form of vinegar is distilled white vinegar. This is the form we use for dyeing and other household chemistry.
Contrary to popular belief, vinegar is not the answer to every problem you may happen to have with dye. Vinegar is not suitable for setting dye in purchased clothing, and it cannot be used to make dyes attach to cotton and other plant fibers. However, it is extremely useful for certain specific other purposes.
Vinegar is not a mordant. Mordants act as connectors between a dye and a textile fiber; if they wash out, they can have no further effect. Vinegar and acetic acid are used to lower the pH of a dyebath, and are easily removed by washing. (See What's the difference between mordants and other chemical assistants used in dyeing?.)
Vinegar contains acetic acid, CH3COOH. Most commercially available vinegar contains 5% acetic acid, volume per volume, though some may contain as little as 4% (the minimum allowed in the US by the FDA standard), or as much as 10% (marketed for use as a cleaner). The remaining 95% is water. Use distilled white vinegar for dyeing, since it lacks the flavorful impurities of wine or malt vinegars. Check to be sure that it contains 5% acetic acid, since you will need to use more of it if it is weaker, or less if it is stronger.
The most concentrated form of acetic acid is called glacial acetic acid. It is a liquid, containing 96% to 99.5% pure acetic acid, whose freezing point is inconveniently high at 16.6°C (62°F), which means it may solidify in an underheated laboratory or studio in the winter. It is not only extremely caustic, it is also flammable at concentrations above 90%, which makes shipping it more difficult and expensive.
A more popular form of concentrated acetic acid is a 56% mixture with waster. Unlike glacial acetic acid, this product is liquid at cool room temperatures, and it is not considered flammable. It is still dangerously caustic, but can be handled safely with appropriate precautions. Look for 56% acetic acid at a photography supply store.
The most common proper use of vinegar in dyeing is to produce an acid pH for acid dyes. Acid dyes, which are used to color protein fibers such as wool, as well as nylon, require a mildly acidic pH to form a permanent bond to the fiber. Vinegar is one of the least expensive and most convenient sources of this acid, especially for beginning dyers. It's safe to work with, safe for shipping, and readily available in grocery stores.
Not all acid dyes require vinegar to be added to the dyebath. Some brands of acid dyes are formulated so that the acid has already been mixed with the dye when you purchase it. Some of these "complete" brands of dyes, with auxiliaries already mixed in, include Landscape Dyes of Australia, Country Classics, Gaywool, and OneShot dyes.
Typical recipes for using vinegar with acid dyes, on silk, nylon, and on wool and other animal fibers, call for different amounts of vinegar depending on the class of acid dye being used. It is always best to find a reputable recipe for the dye, fiber content, and method you're using, and follow it closely.
Acid Levelling dyes are also known as Strong Acid dyes, because they require a lower pH, that is, more acid, than other types of acid dyes. Susan Druding's recipe for acid levelling dye calls for two cups of white vinegar or four tablespoons of 56% acetic acid to dye one pound of fiber in a two-gallon dyebath.
Cushing Perfection acid dyes are also strong acid dyes; the W. Cushing company recommends the use of one cup of vinegar per pound of fiber.
Although Procion MX dyes are fiber reactive dyes when used with a high-pH chemical, such as soda ash, when vinegar or another acid is substituted for the soda ash, they work as acid dyes, on protein fibers such as silk and wool. The amount of acid called for is similar to that required for the leveling acid dyes, much greater than that needed for other classes of acid dyes. For using Procion MX and other fiber reactive dyes as acid dyes on wool, a good quantity is 9 tablespoons of 5%-strength white vinegar per gallon of water in the dyebath, which is the same as 130 ml per 4 liters.
In Dharma Trading Company's recipe for tie-dyeing silk in a microwave, using Procion MX dyes, the recommendation is to use undiluted white vinegar as a presoak for the fabric. In PRO Chemical & Dye's recipe for Direct Application on Wool and Silk using PRO MX Reactive Dyes, the presoak contains equal quantities of water and vinegar.
Other acid dyes do not require as much acidity.
Acid milling dyes include most of the WashFast acid dyes sold by ProChem and other dye retailers, and some of the Jacquard Acid dyes, as well as the milling dyes sold among the Dharma acid dyes. ProChem has an excellent collection of recipes for various uses of their washfast acid dyes, calling for eleven tablespoons of distilled white vinegar for one pound of wool or nylon in two and a half gallons of water (that's 165 ml of vinegar for 450 grams of fiber in 10 liters of water). Their presoak for rainbow dyeing with WashFast Acid Dyes calls for one liter of distilled white vinegar mixed with three liters of lukewarm water and a little Synthrapol.
Dharma suggests using 1/4 cup (60 ml) of vinegar per pound of fabric, though they recommend using ammonium sulfate for both the acid milling and premetallized dyes, instead.
Jacquard recommends one cup of vinegar per top-loading washing-nachine load for their Jacquard Acid Dyes, or 1/4 cup per pound of fabric in a stovetop dyebath, or one tablespoon (15 ml) per quart of dye paint prepared with Jacquard acid dyes (to be heat-set by steamign afterwards).
In addition to beign sold to hand dyers by Kraftkolour in Australia (where the word is spelled "premetallised") and by Dharma Trading Company in the US (they spell it "pre-metallized"), metal complex dyes make up half of the dyes used in the Lanaset range of home dyes, and also include the Jet Black dye color of the WashFast Acid Dyes. Like the milling dyes, they are used at less acidic pHs than the strong acid dyes.
As above, Dharma suggests using 1/4 cup (60 ml) of vinegar per pound of fabric, though they recommend using ammonium sulfate for both the acid milling and premetallized dyes, instead.
ProChem's recipe for rainbow dyeing with Lanaset dyes calls for no auxilliaries other than citric acid or white vinegar, along with a bit of Synthrapol detergent, recommending one liter of white vinegar mixed with three liters of water as a presoak, just as in their recipe for rainbow dyeing with WashFast acid dyes.
However, solid-color immersion dyeing with Lanaset dyes is generally done with a more complex set of auxiliaries, to provide better leveling for a more perfectly smooth solid color. ProChem's recipe calls for 11 Tbl (165 ml) white distilled vinegar, plus sodium acetate crystals, salt, and the special auxilary product Albegal SET, for one pound of fiber in a 10-liter dyebath. Kraftkolour's recipe for Lanaset dyes calls for 20 to 45 ml of 30% acetic acid per pound of fiber, which would work out to equal a range from 120 ml to 270 of 5% white vinegar, instead; the recipe also uses Glauber's salt instead of regular sodium chloride salt.
Since all-purpose dyes, such as Rit All Purpose Dye or Tintex High Temp All Purpose Dye, contain an acid dye, it is a good idea to add vinegar to your dyebath when you are dyeing wool, silk, or nylon. Do not use vinegar when dyeing cotton, as it won't help at all, though it won't really hurt, either. Various manufacturers' recommendations suggest 100 ml per gallon, half a cup per three gallons, or one cup per washing machine load, though these all yield different concentrations of acid.
If you have pH paper, you can easily determine how much vinegar you need to add in order to reach a specific pH in your dyebath, before you add the dye. [This is the same chart as is given on the page How do you use citric acid as an auxiliary chemical for dyeing?.]
| dye class | pH range |
|---|---|
| Leveling acid / Kiton / Strong acid | 2.5 to 3.5 |
| Milling acid / Weak acid | 5.2 to 6.2 |
| Super Milling / Fast Acid | 5.5 to 7.0 |
| Lanaset | 4.5 or 5.0 |
| Procion MX used as acid dyes | 2.5 to 3.5 |
Ammonium sulfate is a slow-release acid that may give more level results than vinegar or citric acid.
For greater precision in getting the right pH for your dyebath, use a combination of acetic acid and its salt, sodium acetate. Combining sodium acetate with acetic acid will result in a higher pH than acetic acid alone, and a lower one than sodium acetate alone, but, more importantly, a buffer system that contains both an acid and its salt will maintain its pH better, with less chance of unexpected changes. Karren Brito gives clear instructions for using sodium acetate with acetic acid for dyeing silk with Lanaset dyes in her excellent book, Shibori: Creating Color and Texture On Silk
Acetic acid fumes make boiling vinegar a smelly experience. Unlike many acids, acetic acid does boil off into the air to a significant extent when heated, though the boiling point is, at 117-8°C, higher than that of water. Dyers who dislike filling the house with acetic acid fumes substitute other acids, such as citric acid, for vinegar. Some dyers add vinegar to the water in their steaming apparatus in order to use the acetic acid in the vapor to provide a lower pH in material being steamed, as an aid in fixing acid dyes.
After dyeing a protein fiber such as silk or wool with any high-pH chemical, such as the lye used in dyeing with indigo and other vat dyes, or the soda ash used with most fiber reactive dyes, it's kinder to the fibers if you restore the pH to neutral when you are finished. After rinsing out dyes and other chemicals, dilute two tablespoons (30 ml) of white vinegar in a gallon (or 4 liters) of water. Soak your dyed material in this solution, then rinse.
In order to prevent odors from microbial growth, especially in towels, add vinegar to the final rinse of your laundry cycle, using the washing machine's automatic dispenser for liquid fabric softeners. Use one-half to three-quarters of a cup of vinegar for a top-loading machine; use less in a front loading machine, perhaps as little as two tablespoons.
Vinegar is so safe to use that you may imagine that acetic acid is generally safe. Don't make that mistake!
Concentrated 56% acetic acid, which is 11 times as strong as most vinegar, is strong enough to badly burn skin or eyes. Remember, always add acid to water, not water to acid, so that it doesn't spatter at you, and always wear eye protection and good long waterproof gloves when working with it. Latex or nitrile gloves are not protective against concentrated acetic acid; use neoprene or butyl rubber gloves instead.
Don't buy glacial acetic acid, if you can get 56% acetic acid, instead; the more dilute acetic acid is safer to ship and to store, and more convenient to use, as well. Concentrations of acetic acid above 25% call for use in a fume hood, not commonly available in art studios. If you do not have access to a fume hood, use a properly fitted respirator with acid gas cartidges to protect you against the fumes.
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Last updated: January 7, 2012
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