Dye
DEFINITION
A dye is a colorant or pigment that dissolves completely, and is translucent. Textile fibers and fabrics are typically dyed in vats of the stuff. Because dyes are mixed with liquids just before their use, commercially produced dyes are highly concentrated. Natural dyes have been derived from a wide range of plant and animal sources, and are sometimes referred to as dyestuff. POISONOUS!Dyes color by penetrating substances, in contrast to drawing and painting colors, which must simply adhere to surfaces. There are many types of dyes, varying in their effects, the means of their use, and permanence.Many dyes are toxic, so be sure to read the warnings below as well as those on labels. Use caution!TAKE NOTE!Dye powders are very fine, and therefore dangerous if inhaled. WEAR PROTECTIVE CLOTHING!They should be mixed when wholly immersed in water oWEAR A DUST MASK!r, if this is not possible, wear a dust mask or respirator. Wear heavy-duty rubber gloves to avoid skin contamination. Do not use cooking utensils, because they may retain potentially hazardous amounts of chemicals. Wear personal protective clothing, and do not eat, drink or smoke in a dyeing area. Only soap and water should be used to remove splashes from the skin, because chemical substances such as bleach or potassium mangate might break down the dyes into hazardous substances.Direct dyes (aka direct benzidine-type dyes) are a component of all-purpose dyes. These may be toxic.Acid dyes are used for silk and wool, and are probably the least hazardous.Basic dyes, used for wool, silk and some synthetics, may cause allergic reactions.Procion dyes are also known as fiber-reactive or cold water dyes. Reactive dyes are extremely reactive chemical compounds and are capable of reacting with body tissue. The respiratory tract is particularly sensitive to reactive dyes and allergic responses may occur. Symptoms may seem like hay fever or asthma, accompanied by swollen eyes.Synthetic mordant dyes may be used in dyeing wool. Alum (potassium aluminium sulphate) salts of tin or iron should be used instead of more hazardous mordant salts, the most hazardous of which is potassium dichromate. Avoid other metal salts, including chromium cobalt and copper, because they may be both toxic and corrosive.The constituent materials of azoic dyes, 'fast bases' (fast salts) and napthol or naphthalene, are highly reactive chemical compounds capable of causing dermatitis and other skin disorders.Also see alizarin, batik, blot, die, eyedropper, fluorescent colors, mortar and pestle, process, and stain.