Tuesday, September 6, 2011

Dyeing Glossary

This is the handout from the Dyeing panel I gave at DragonCon.

Acid Dye – dye that is good for protein fibers. Uses an acid to bond the dye, and usually needs high temperatures.

Adjective Dyes – use a mordant to bond the dye to the fabric.

Aniline Dyes – dyes derived from coal tar, first synthetic dyes discovered. Rarely used now (mostly just leather) because they are very toxic and not very colorfast.

Antichlor – a neutralizer for chlorine bleach. There are safe versions, such as hydrogen peroxide and Sodium Thiosulfate, and dangerous versions that produce toxic chlorine gas when in reaction with chlorine bleach such as vinegar and Sodium Bisulfate.

Binder – the “glue” of a paint. Some paints can be purchased as a separate “binder” and “pigment” to allow the user to mix their own paint.

Burn-in – when the dyeing process destroys the fibers of the fabric. This is especially a problem with polyesters in professional dyeing. There is no solution to this.

Carrier – a chemical that helps to dye polyester at a lower temperature. Thought to swell the fibers to allow the dye to penetrate into them. Most are noxious and harmful to the home user.

Cationic Dye – dye for acrylic fibers. Uses a base to bond the dye. Hard to find non-commercial suppliers.

Cellulose Fibers – fibers that have a cellulose, plant base. These include linen, hemp, ramie, jute, cotton, rayon, bamboo, pineapple, etc.

Citric Acid – a powdered acid used in acid dyeing.

Colorfast Dyes – dyes of any type that are resistant to fading, rubbing off, bleeding in wash water, or otherwise changing their color.

Devore – using an etching solution to make a pattern in a fabric.

Discharge – removing dye with bleach or a chemical dye remover. Bleach removal should be stopped with antichlor.

Dyed in the Wool – fibers that are dyed before they are spun into yarn and woven into fabric.

Dyestuff – material that releases a dye. Can be a chemical powder or a natural plant or chemical.

Etching Solution – a chemical that dissolves specific fibers. There are cellulose-specific and protein-specific solutions. Can be use to dissolve patterns in fibers or to make a lace-like material out of fiber type blends.

Disperse Dye – a dye that suspends rather than dissolving in water. Usually uses a carrier to dye fabric. Used on polyester, nylon, and acetate.

Dye – a color that attaches directly to fibers in molecular form to change the fabric’s color without the use of a binder.

Electrolyte – changes the conductivity of the dye bath. Fibers in water commonly develop a negative charge at their surface, and dyes are commonly negatively charged as well so they repel each other. An electrolyte helps to overcome this repelling by ionizing the water and overcoming the surface tensions of the liquid and the fibers. The most common electrolytes used in dyeing are salt and acids.

Exhaustion – when all the dye in the dye bath has attached to the fiber and there is no more dye to color with.

Fixative – a chemical that permanently bonds dye to fibers so they are wash-fast. Soda Ash is commonly called a fixative, but it is actually a reactant.

Garment Dyed – fabric that is dyed after it has been woven, cut, and sewn into a garment or yarn knitted into a piece before dyeing.

Griege – fabric that is undyed, unbleached, sized, and possibly dirty.

Humectant – a chemical that prevents dye solution from drying out before fixing to the fibers. Most common is Urea.

Low Immersion Dye – when a strong solution of dye is poured over a fabric, barely covering the fabric.

Mercerization – a treatment of sodium hydroxide applied to cotton to make the fibers swell and accept dye more readily. Also softens the hand of the fabric.

Mordant – a chemical that bonds with both the dye and the fiber, making it easier for the fabric to dye. Commonly used in natural dyeing, common mordants are alum, urea, chromium, copper, sodium, aluminum, and tin. Mordants commonly change the color of a dye.

MSDS - Material Safety Data Sheet. OSHA regulates that these must be available to workers. Prepared by the company that makes the product, these sheets detail the chemicals used in the product and safety measures that should be taken to ensure no harm comes to the user of the product.

MX Dye – a reactive dye that is popular with hobbyists because of its ease of use and low temperatures needed to use.

Natural Dyes – dyes derived from animals, plants, minerals, fungi and lichens.

Ombre – dyeing fabric in a gradient, from dark to light, or fading from one color to another with no discernible breaks.

Optical Whitener – a “dye” that reflects light in a visible bluish hue when exposed to ultraviolet light. This bluish light helps to mask any natural yellow colors in a fiber, making it appear whiter to the naked eye.

Overdyeing – dyeing a fabric that has already been dyed.

Piece-Dyed – fabric that is dyed after the yarn is woven into fabric.

Pigment – a large molecule of color that does not dissolve in water. Pigments require a binder to bond with fibers.

Prepared for Dyeing – fabric that has been bleached but has no sizing, optical whiteners, lubricating oils, or softeners to interfere with the dyeing chemical process.

Printing – using a mechanical resist or application to selectively apply dye. Includes screen-printing, stamping, and transfers.

Protien Fibers – fibers that have a protein base. These include hairs (wool, cashmere, etc), silk, and nylon. These fibers can be dissolved or destroyed with chlorine bleach.

Reactant – a chemical added to cause a reaction. Some dyes are reactant themselves, others require a mordant, acid, or base.

Reactive Dye – dye that bonds to fibers with a covalent bond. Best on cellulose fibers.

Resist – something that is applied to fabric to prevent it from bonding with dye.

~~Chemical Resist – a chemical that prevents a dye from bonding.

~~Mechanical Resist – an object such as a thread or clip that prevents dye from reaching the fibers

~~Paste Resist – a paste such as wax that seals fibers to prevent the dyebath from reaching them.

Retarder – a chemical that prevents dyes from quickly bonding to fibers. Used to help achieve a more even dye color.

Scouring – Removing all contaminants from fibers before dyeing. Must be done with a detergent that does not have optic whiteners or softeners added that can interfere with dyeing. Soda Ash and Synthrapol are common scouring agents.

Shibori – A class of Japanese resist techniques that uses binding, stitching, folding, clamping(Itajime) and pole wrapping (Arashi) to get different dye patterns.

Sizing – a chemical used to treat yarns and fabrics to smooth and bind them together. Used to make weaving easier and less destructive to the yarns of the fabric. Can interfere with the dyeing process.

Soaping – washing dyed fabrics with a surfactant and hot water to remove dye that is in the fabric but not bonded to the fibers. Very important with reactive dyes.

Softener – a chemical that lubricates fibers, coating them and allowing them to slide across each other more easily, reducing static charge and giving the fabric a softer feel to the hand. Can interfere with the dyeing process.

Stripping – removing dye from fibers, commonly using sodium hydrosulfite and a very hot water temperature. Result is usually not white fabric.

Substantive Dyes – color fibers without a mordant.

Surfactant – a chemical that lowers the surface tension of a liquid allowing molecules to more readily dissolve in that liquid. Electrolytes are surfactants, but not all surfactants are electrolytes.

Tea Dyeing – using tea (and sometimes coffee) to color a fabric or item tan, beige, or other shade of non-white. In my experience black teas are often a reddish hue, coffee has a yellowish tinge, and green teas have a greenish tinge. Speeds rotting of fabric, causing it to decay faster (shortens lifespan of fabric by 30-50 years).

Tie Dyeing – using flexible mechanical resists such as strings or rubber bands to make patterns in a fabric.

Union Dye – dye that is a mixture of two or more kinds of dye. Used for home dyers to dye a variety of fibers in a very inaccurate way, or in industrial applications to accurately dye blended fibers.

Vat Dye – when a fabric is immersed in a dye bath.

Wetting Agent – helps a dye to penetrate a material, synonymous with surfactant until you get really into dyeing chemistry.

Yarn Dyed – yarn that is dyed after the fibers are spun but before the yarn is woven into fabric.


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