A mordant or dye fixative is a substance used to set dyes on fabrics by forming a coordination complex with the dye, which then attaches to the fabric. It may be used for dyeing fabrics or for intensifying stains in cell or tissue preparations. Although mordants are still used, especially by small batch dyers, it has been largely displaced in industry by directs.
Bromothymol blue is a pH indicator. It is mostly used in applications that require measuring substances that would have a relatively neutral pH. A common use is for measuring the presence of carbonic acid in a liquid. It is typically sold in solid form as the sodium salt of the acid indicator.
Sulfur dyes are the most commonly used dyes manufactured for cotton in terms of volume. They are inexpensive, generally have good wash-fastness, and are easy to apply. Sulfur dyes are predominantly black, brown, and dark blue. Red sulfur dyes are unknown, although a pink or lighter scarlet color is available.
Phthalocyanine Blue BN, also called by many names, is a bright, crystalline, synthetic blue pigment from the group of phthalocyanine dyes. Its brilliant blue is frequently used in paints and dyes. It is highly valued for its superior properties such as light fastness, tinting strength, covering power and resistance to the effects of alkalis and acids. It has the appearance of a blue powder, insoluble in most solvents including water.
Coomassie Brilliant Blue is the name of two similar triphenylmethane dyes that were developed for use in the textile industry but are now commonly used for staining proteins in analytical biochemistry. Coomassie Brilliant Blue G-250 differs from Coomassie Brilliant Blue R-250 by the addition of two methyl groups. The name "Coomassie" is a registered trademark of Imperial Chemical Industries.
Dyeing is the application of dyes or pigments on textile materials such as fibers, yarns, and fabrics with the objective of achieving color with desired fastness. Dyeing is normally done in a special solution containing dyes and particular chemical material. Dye molecules are fixed to the fibre by absorption, diffusion, or bonding with temperature and time being key controlling factors. The bond between dye molecule and fibre may be strong or weak, depending on the dye used. Dyeing and printing are different applications; in printing color is applied to a localized area with desired patterns and in dyeing it is applied to the entire textile.
Indanthrone blue, also called indanthrene, is an organic dye made from 2-aminoanthraquinone treated with potassium hydroxide in the presence of a potassium salt. It is a pigment that can be used in the following mediums: acrylic, alkalyd, casein, encaustic, fresco, gouache, linseed oil, tempera, pastel, and watercolor painting. It is used to dye unmordanted cotton and as a pigment in quality paints and enamels. As a food dye, it has E number E130, but it is not approved for use in either the United States or the European Union. The pigment has a color index name of PB60. Indanthrene Blue RS was patented in 1901 by Rene Bohn as the first anthraquinone vat dye, one of the dyes with very good fastness to light and washing.
Acid-fastness is a physical property of certain bacterial and eukaryotic cells, as well as some sub-cellular structures, specifically their resistance to decolorization by acids during laboratory staining procedures. Once stained as part of a sample, these organisms can resist the acid and/or ethanol-based decolorization procedures common in many staining protocols, hence the name acid-fast.
An acid dye is a dye that is typically applied to a textile at low pH. They are mainly used to dye wool, not cotton fabrics. Some acid dyes are used as food colorants.
Brilliant Blue FCF is a synthetic organic compound primarily used as a blue colorant for processed foods, medications, dietary supplements, and cosmetics. It is classified as a triarylmethane dye and is known under various names, such as FD&C Blue No. 1 or Acid Blue 9. It is denoted by E number E133 and has a color index of 42090. It has the appearance of a blue powder and is soluble in water and glycerol, with a maximum absorption at about 628 nanometers. It is one of the oldest FDA-approved color additives and is generally considered nontoxic and safe.
Vat dyes are a class of dyes that are classified as such because of the method by which they are applied. Vat dyeing is a process that refers to dyeing that takes place in a bucket or vat. Almost any dye, including fiber-reactive dyes, direct dyes, and acid dyes, can be used in a vat dye. Cotton, wool, leather and other fibers can be all dyed with vat dyes. The original vat dye is indigo, once obtained from plants but now produced synthetically.
Litmus is a water-soluble mixture of different dyes extracted from lichens. It is often adsorbed onto filter paper to produce one of the oldest forms of pH indicator, used to test materials for acidity.
Kermes is a red dye derived from the dried bodies of the females of a scale insect in the genus Kermes, primarily Kermes vermilio. The Kermes insects are native in the Mediterranean region and live on the sap of the Kermes oak. They were used as a red dye by the ancient Greeks and Romans. The kermes dye is a rich red, a crimson. It has good colour fastness in silk and wool. It was much esteemed in the medieval era for dyeing silk and wool, particularly scarlet cloth. Post-medievally it was replaced by other red dyes, starting with cochineal.
A solvent dye is a dye soluble in organic solvents. It is usually used as a solution in an organic solvent.
Ring dyeing is a type of dyeing fault in which dyes are partially diffused to the interior of fibre. Most dyes are stained on to the fibre surface that form layer of dyes on to fibre surface. Thus around the fibre a ring-like appearance of the dye can be viewed cross-sectionally. This ring-like dye layer opposes further dye diffusion. This problem leads to poor wash fastness and rubbing fastness of dyed fabric, as well as other staining-related fastness properties.
Triarylmethane dyes are synthetic organic compounds containing triphenylmethane backbones. As dyes, these compounds are intensely colored. They are produced industrially as dyes.
Michler’s ketone is an organic compound with the formula of [(CH3)2NC6H4]2CO. This electron-rich derivative of benzophenone is an intermediate in the production of dyes and pigments, for example Methyl violet. It is also used as a photosensitizer. It is named after the German chemist Wilhelm Michler.
Lightfastness is a property of a colourant such as dye or pigment that describes how resistant to fading it is when exposed to light. Dyes and pigments are used for example for dyeing of fabrics, plastics or other materials and manufacturing paints or printing inks.
Colour fastness is a term—used in the dyeing of textile materials—that characterizes a material's colour's resistance to fading or running. The term is usually used in the context of clothes. In general, clothing should be tested for colorfastness before using bleach or other cleaning products.
