Arylide yellow | |
---|---|
Color coordinates | |
Hex triplet | #E9D66B |
sRGB B (r, g, b) | (233, 214, 107) |
HSV (h, s, v) | (51°, 54%, 91%) |
CIELChuv (L, C, h) | (85, 71, 76°) |
Source | |
ISCC–NBS descriptor | Brilliant greenish yellow |
B: Normalized to [0–255] (byte) |
Arylide yellow, also known as Hansa yellow and monoazo yellow, is a family of organic compounds used as pigments. They are primarily used as industrial colorants including plastics, building paints and inks. They are also used in artistic oil paints, acrylics and watercolors. These pigments are usually semi-transparent and range from orange-yellow to yellow-greens. Related organic pigments are the diarylide pigments. Overall, these pigments have partially displaced the toxic cadmium yellow in the marketplace. Painters such as Alexander Calder and Jackson Pollock are known to have employed arylide yellow in their artworks. [1]
The compound is obtained by azo coupling of aniline and acetoacetanilide or their derivatives. The class of compounds was discovered in Germany in 1909. [2]
Members of this class include:
In chemistry, amines are compounds and functional groups that contain a basic nitrogen atom with a lone pair. Amines are formally derivatives of ammonia, wherein one or more hydrogen atoms have been replaced by a substituent such as an alkyl or aryl group. Important amines include amino acids, biogenic amines, trimethylamine, and aniline. Inorganic derivatives of ammonia are also called amines, such as monochloramine.
A pigment is a powder used to add color or change visual appearance. Pigments are completely or nearly insoluble and chemically unreactive in water or another medium; in contrast, dyes are colored substances which are soluble or go into solution at some stage in their use. Dyes are often organic compounds whereas pigments are often inorganic. Pigments of prehistoric and historic value include ochre, charcoal, and lapis lazuli.
Aniline is an organic compound with the formula C6H5NH2. Consisting of a phenyl group attached to an amino group, aniline is the simplest aromatic amine. It is an industrially significant commodity chemical, as well as a versatile starting material for fine chemical synthesis. Its main use is in the manufacture of precursors to polyurethane, dyes, and other industrial chemicals. Like most volatile amines, it has the odor of rotten fish. It ignites readily, burning with a smoky flame characteristic of aromatic compounds. It is toxic to humans.
Azo compounds are organic compounds bearing the functional group diazenyl.
Azo dyes are organic compounds bearing the functional group R−N=N−R′, in which R and R′ are usually aryl and substituted aryl groups. They are a commercially important family of azo compounds, i.e. compounds containing the C-N=N-C linkage. Azo dyes are synthetic dyes and do not occur naturally. Most azo dyes contain only one azo group but there are some that contain two or three azo groups, called "diazo dyes" and "triazo dyes" respectively. Azo dyes comprise 60-70% of all dyes used in food and textile industries. Azo dyes are widely used to treat textiles, leather articles, and some foods. Chemically related derivatives of azo dyes include azo pigments, which are insoluble in water and other solvents.
Diazonium compounds or diazonium salts are a group of organic compounds sharing a common functional group [R−N+≡N]X− where R can be any organic group, such as an alkyl or an aryl, and X is an inorganic or organic anion, such as a halide.
In organic chemistry, an azo coupling is an organic reaction between a diazonium compound and another aromatic compound that produces an azo compound. In this electrophilic aromatic substitution reaction, the aryldiazonium cation is the electrophile and the activated carbon act as a nucleophile. In most cases, including the examples below, the diazonium compound is also aromatic.
Benzidine (trivial name), also called 1,1'-biphenyl-4,4'-diamine (systematic name), is an organic compound with the formula (C6H4NH2)2. It is an aromatic amine. It is a component of a test for cyanide. Related derivatives are used in the production of dyes. Benzidine has been linked to bladder and pancreatic cancer.
Nitrophenols are compounds of the formula HOC6H5−x(NO2)x. The conjugate bases are called nitrophenolates. Nitrophenols are more acidic than phenol itself.
3-Nitroaniline is an organic compound with the formula H2NC6H4NO2. A yellow solid, it is a derivative of aniline, carrying a nitro functional group in position 3. It is an isomer of 2-nitroaniline and 4-nitroaniline. It is used as a precursor to dyes.
2-Nitroaniline is an organic compound with the formula H2NC6H4NO2. It is a derivative of aniline, carrying a nitro functional group in position 2. It is mainly used as a precursor to o-phenylenediamine.
4-Nitroaniline, p-nitroaniline or 1-amino-4-nitrobenzene is an organic compound with the formula C6H6N2O2. A yellow solid, it is one of three isomers of nitroaniline. It is an intermediate in the production of dyes, antioxidants, pharmaceuticals, gasoline, gum inhibitors, poultry medicines, and as a corrosion inhibitor.
Diketene is an organic compound with the molecular formula C4H4O2, and which is sometimes written as (CH2CO)2. It is formed by dimerization of ketene, H2C=C=O. Diketene is a member of the oxetane family. It is used as a reagent in organic chemistry. It is a colorless liquid.
1,2-Dichloro-4-nitrobenzene is an organic compound with the formula 1,2-Cl2C6H3-4-NO2. This pale yellow solid is related to 1,2-dichlorobenzene by the replacement of one H atom with a nitro functional group. This compound is an intermediate in the synthesis of agrochemicals.
2,4-Dinitroaniline is a chemical compound with a formula of C6H5N3O4. It is used as an explosive and as a reagent to detect and characterize aldehydes and ketones.
Diarylide pigments are organic compounds that are used as pigments in inks and related materials. They often are yellow or yellow-green. To some extent, these organic compounds have displaced cadmium sulfide from the market. They exist as yellow powders of low solubility in water.
Acetoacetanilide is an organic compound with the formula CH3C(O)CH2C(O)NHC6H5. It is the acetoacetamide derivative of aniline. It is a white solid that is poorly soluble in water. This chemical and many related compounds (prepared from various aniline derivatives) are used in the production of organic pigments called arylide yellows. Acetoacetanilides usually exist as the keto-amide tautomer according to X-ray crystallography.
1,4-Dichloro-2-nitrobenzene is an organic compound with the formula C6H3Cl2NO2. One of several isomers of dichloronitrobenzene, it is a yellow solid that is insoluble in water. It is produced by nitration of 1,4-dichlorobenzene. It is a precursor to many derivatives of commercial interest. Hydrogenation gives 1,4-dichloroaniline. Nucleophiles displace the chloride adjacent to the nitro group: ammonia gives the aniline derivative, aqueous base gives the phenol derivative, and methoxide gives the anisole derivative. These compounds are respectively 4-chloro-2-nitroaniline, 4-chloro-2-nitrophenol, and 4-chloro-2-nitroanisole.
A colorant is any substance that changes the spectral transmittance or reflectance of a material. Synthetic colorants are those created in a laboratory or industrial setting. The production and improvement of colorants was a driver of the early synthetic chemical industry, in fact many of today's largest chemical producers started as dye-works in the late 19th or early 20th centuries, including Bayer AG(1863). Synthetics are extremely attractive for industrial and aesthetic purposes as they have they often achieve higher intensity and color fastness than comparable natural pigments and dyes used since ancient times. Market viable large scale production of dyes occurred nearly simultaneously in the early major producing countries Britain (1857), France (1858), Germany (1858), and Switzerland (1859), and expansion of associated chemical industries followed. The mid-nineteenth century through WWII saw an incredible expansion of the variety and scale of manufacture of synthetic colorants. Synthetic colorants quickly became ubiquitous in everyday life, from clothing to food. This stems from the invention of industrial research and development laboratories in the 1870s, and the new awareness of empirical chemical formulas as targets for synthesis by academic chemists. The dye industry became one of the first instances where directed scientific research lead to new products, and the first where this occurred regularly.
Naphtholactam is an organic compound derived from naphthalene. It is a tricyclic species consisting of a naphthalene core fused with a lactam (NH-CO-) at the 1,8-positions. The N-alkyl derivatives are commercially important.