Dyeing is the art and science of applying color to fiber, yarn, or fabric, usually by immersing the material in a dye bath. Dyes or colorants fall into two main categories: natural dyes, derived from plants, invertebrates, or minerals, and synthetic dyes, developed in laboratories, primarily from petroleum-based chemicals.


For thousands of years, from the Neolithic period through the mid-19th century, textiles were colored exclusively with natural dyes. That changed in 1856, when William Henry Perkin accidentally created mauveine (aniline purple), the first synthetic dye. Affordable, colorfast, and easily reproduced, synthetic dyes rapidly displaced natural dyes on a commercial scale. Today, however, growing awareness of environmental and health concerns is fueling renewed interest in naturally dyed textiles.

Materials and Tools:

  • Auxiliary Chemicals: Various chemicals that prepare fibers to accept dye, help the dye attach evenly, enhance colorfastness, regulate the pH of the dyebath, and more.
  • Dyes come in many forms: Chemical dyes are generally powders but are also available as liquids and pastes. Natural dyes can be fresh, dried, or in extract form.
  • Dye pots must be large enough to hold both the material to be dyed and sufficient water to ensure good circulation. Stainless steel is ideal because it does not react with the dye. For unheated dyes, plastic tubs and buckets work well.
  • A heat source, such as a hot plate, camping stove, or the sun, is often required.
  • Materials: Both natural and synthetic fibers can be dyed. The fiber type dictates the suitable type of dye and dyeing method.
  • Measuring equipment,  including measuring cups and spoons, an accurate scale, and a thermometer. 
  • Safety equipment, including a mask/respirator to prevent inhalation of powdered dyes and auxiliary chemicals, and rubber gloves.  NOTE:  All dye pots and equipment should be dedicated to dyeing and never used for food preparation. 

Terminology:


  • Depth of Shade (DOS) is the amount of dye relative to the material being dyed. It is calculated as a percentage: For example, 1% DOS means 1 gram of dye powder for every 100 grams of fiber.
  • Dyebath: A liquid solution of water, dye, and auxiliary chemicals used to color materials.
  • Direct or substantive dyes bond directly to fibers without the need for a mordant. Examples are onion skins, indigo, and black walnut.
  • Hue is another word for color.
  • Modifiers are substances applied after natural dyeing that change and extend the color available from a single dyebath - acidic modifiers generally make colors yellower, alkaline modifiers generally make colors pinker, iron modifiers darken and make colors more somber, and copper modifiers make colors greener or browner.
  • Mordant:  A substance that forms a chemical bond between a natural dye and a fiber, setting the color and making it permanent. Alum is the most commonly used non-toxic mordant. 
  • Natural fibers come from plants and animals.
  • Cellulose fibers come from plants and include cotton, flax, hemp, and ramie. 
  • Protein fibers come from animals and include wool, silk, mohair, and alpaca.
  • pH is a scale from 0 to 14 that measures how acidic or alkaline (basic) a dyebath is. A pH of 7 is neutral, like pure water. A pH below 7 is acidic, like lemon juice, while a pH above 7 is alkaline or basic, like household ammonia. 
  • Regenerated cellulose fibers are derived from a natural source like wood pulp or cotton linters, but undergo a chemical process to be regenerated into a usable fiber. Common examples include rayon, modal, Tencel, and bamboo, which are treated as cellulose fibers for dyeing.
  • Scouring is a thorough cleaning and rinsing process that removes natural and manufacturing impurities from the materials to be dyed, including waxes, oils, starches, and dirt. Scouring makes materials more receptive to dyes, resulting in more even and more vibrant dyed colors. 
  • Stock solutions are mixtures of water and dye (usually at 1% DOS). They are safer and easier to handle than dry powders, and enable you to more accurately and consistently measure your dye.
  • Synthetic fibers are man-made fibers derived from petroleum-based chemicals, including polyester, nylon, acrylic, and spandex.
  • Weight of Goods (WOG) or Weight of Fiber (WOF):  The weight in grams or ounces of the material being dyed. 

Process:

General directions for immersion dyeing:



Preparation:

  • Scour materials to be dyed.
  • Mordant materials to be dyed if using most natural dyes.
  • Thoroughly wet the fabric and squeeze out excess water if using previously scoured and mordanted materials.
  • Prepare the dye bath.

Dyeing:

  • Immerse the material in the dye bath. 
  • Stir the material frequently for the first few minutes to ensure consistent color distribution. 
  • Allow sufficient time for dye uptake, stirring occasionally to maintain color levelness. 

Post-Dyeing:

  • If required, heat-set or batch-age the dyed materials.
  • Rinse the dyed material until the water runs clear. 
  • Dry the dyed material.

Variations:

  • Dip dyeing: The material is dipped into the dyebath in stages, producing gradient or ombre effects where color changes gradually.
  • Discharge dyeing selectively removes color from a previously dyed material to create a pattern. This is done by applying a chemical paste containing a stripping or reducing agent to fiber or cloth or immersing it in a chemical discharge solution.
  • Dye painting is the placement of liquid dye with a brush or applicator, controlling color placement. Dyes can also be thickened to print, stencil, and stamp on cloth.
  • Eco printing is a natural dyeing technique that uses plant materials to directly print patterns and colors on fabric or paper. 
  • Ice dyeing:  Dry fiber-reactive dye powder is sprinkled onto a layer of ice that covers the material. As the ice melts, it carries the dye through the material.
  • Immersion or vat dyeing: The material to be dyed is fully submerged in a dye bath with a large ratio of water to dye, allowing the material to absorb color evenly.
  • Resist dyeing includes any technique that creates pattern by selectively preventing dye penetration:
  • Mechanical resists include rubber bands/string (tie dyeing), stitching/binding/clamping (shibori), selectively binding and dyeing threads before weaving (ikat), and stencils.
  • Barrier resists include wax (batik) and pastes made from starch, clay, or other materials (Adire and Katazome). 

FAQ's:

  • Is dyeing safe? Yes, with care: Wear a mask when working with powders and wear gloves. Work outdoors or in a well-ventilated area. Always keep dye tools separate from your food/kitchen tools.
  • Can I save leftover dye? Yes, generally. It’s a good practice to label your dyestuffs with the date you acquired them or mixed them into a solution.
  • Natural dye baths can last a few days if refrigerated, or you can strain and dry fresh plant material for later use. 
  • Chemical stock solutions can be stored in jars or bottles for weeks or longer, depending on the type of dye. Powdered dyes will weaken over time, and their shelf life can be compromised by exposure to moisture, heat, or light.
  • What is the difference between dye and pigment?  It boils down to their solubility in water. Dyes are water-soluble and form stable chemical bonds with fiber, so they become part of the fibers they color. Pigments are not water-soluble, so they sit on the surface of the fiber or cloth.
  • Are colors repeatable? Yes, with chemical dyes if you precisely control your materials and methods. No, with natural dyes, since growing conditions will always vary. Still, you can minimize variations by controlling other variables such as mordant and water source, and maintaining good records.
  • What are the most common types of chemical dyes?
  • Acid dyes are water-soluble dyes primarily used to color natural protein fibers (like wool and silk), nylon, and some acrylics. They create strong, long-lasting colors using a weak acid like vinegar or citric acid as a catalyst.
  • Fiber-reactive dyes like Procion MX are primarily used on cellulose fibers like cotton and linen, and regenerated cellulose fibers like rayon and Tencel. They are applied in a weak alkaline dyebath.
  • All-purpose or union dyes are multi-purpose, all-in-one dye blends (RIT, Dylon, and Cushings) that are formulated to work on a variety of fabric types. 
  • Solar dyes are light-reactive dyes (Inkodye and Jacquard Solar Fast) that develop color and become permanent upon exposure to UV light.
  • Tell me about indigo.  Natural indigo is a pigment derived from the leaves of plants. It is applied to fibers by first reducing it in an alkaline, oxygen-deprived vat and then oxidizing it in the air. The depth of the resulting blue color is controlled by many factors, including the fiber type, the strength of the vat, and the number of dips. There is also a synthetic version of indigo available that is synthesized from petrochemicals.