Hair Dyeing

2-Naphthol, a compound of great importance in the field of chemistry, is the product of a series of metabolic processes in living organisms, mainly catalyzed by isozymes of the cytochrome P450 family, such as CYP 1A1, CYP 1A2, CYP 2A1, CYP 2E1, and CYP 2F2. This compound exists in the form of dry powder or liquid/solid, with a crystalline appearance ranging from white to pale yellow, emitting a unique odor, which is a distinctive chemical characteristic. The structural feature of 2-naphthol lies in its naphthol structure with a hydroxyl group at the 2nd position, which endows it with a series of biological activities. It is recognized as an antinematode agent, exerting inhibitory effects on nematodes, while its chemical properties also make it considered a genetically toxic substance, potentially affecting genetic material. Furthermore, 2-naphthol is an exogenous metabolite of humans and mice, commonly found in human urine, showing its metabolic pathway in the body. It also possesses the characteristic of a free radical scavenger, possibly participating in the body's antioxidant mechanism. In terms of physical and chemical properties, the density of 2-naphthol is 1.28 g/cm³ at 20°C, its melting point is 121.6°C, and its boiling point is 285°C, with a certain degree of volatility. Its flash point is 160°C, indicating the risk of fire or explosion in high-temperature environments. Its refractive index is 1.548, and its water solubility is extremely low, only able to dissolve in water at extremely low concentrations (1 g/L, 20°C). These characteristics are crucial for safe handling in laboratories and industrial production. When storing and handling 2-naphthol, strict adherence to safety regulations must be followed. It should be stored away from heat sources, sparks, and flames, and should be avoided in contact with open flames. At the same time, it should be stored away from direct sunlight to prevent it from degrading due to photochemical reactions. Keeping the container closed can prevent evaporation and reaction with oxygen in the air. The vapor pressure of 2-naphthol is 10 mm Hg (145.5°C) and its vapor density is 4.97 (relative to air), indicating that it may form flammable vapors under certain conditions. It has a weak phenolic odor and may irritate the respiratory system. Additionally, its hydroxyl radical reaction rate constant and autoignition temperature, among other parameters, reveal the chemical reactions it may participate in under certain conditions, suggesting that extra care is needed when handling and using it. In experimental operations, appropriate personal protective equipment such as chemical protective goggles, respiratory protection devices, and chemical protective gloves should be used to prevent skin contact and inhalation of its vapors. If accidental inhalation occurs, personnel should be immediately moved to fresh air and seek medical assistance. After skin contact, immediate rinsing with plenty of water should be done and medical attention sought promptly. Additionally, 2-naphthol may also contaminate the environment, so any spills or waste should be disposed of according to local regulations and not discarded carelessly. In analysis and synthesis work, special sealed equipment is typically used for operation to reduce exposure and prevent leaks. In cases where heating is required, a water bath or oil bath should be used, avoiding direct flame heating to reduce the risk of fire or explosion. At the same time, its solutions should be stored in a dark place to slow down its possible photochemical reactions. The solubility of 2-naphthol is higher in organic solvents such as alcohol, ketone, and ether, which makes it have certain application value in organic synthesis. However, these characteristics also increase the risk of forming a mixture of solvent vapors during handling, so it should be carried out in a well-ventilated environment and with good ventilation facilities. Understanding these properties of 2-naphthol is crucial in research and industrial production, not only for the safety of experimental personnel but also for the quality of products and environmental protection. Therefore, it is necessary to have a thorough understanding of the properties of 2-naphthol and strictly follow safety operating procedures before conducting related work.

2-Aminophenol is an isomer of 4-Aminophenol (A618920) and is used as a reagent for the synthesis of heterocyclic compounds and dyes.

Off-white crystal powder/granuale

Used in organic synthesis, it is an intermediate of anti-AIDS drugs

It is used to prepare acidic medium RH, acid complex purple 5RN and reactive dyes, and it can also be used to prepare chlorzoxazone

Used in the preparation of medicines, dyes and explosives Used as medicine, pesticide, dye intermediate, hair auxiliaries, etc.

manufacture of dyes, paint colorings, rubber chemicals, and fungicides.Indicator in 2% alcohol solution.pH:5.0 colorless, 7.0 yellow, but the color change is not sharp and cannot be used where CO2 is present; as reagent for glucose.

2,5-Toluenediamine is used primarily in hair dye formulations as one of the major oxidation dye precursors. It is also used in the synthesis of saframine, a family of dyes used as biological stain, and may be present in indelible ink, antifreeze, and nail polish.
As may be expected from its use in hair dye formulations, hairdressers and barbers may be exposed to 2,5-TDA. Workers in the dye manufacturing industry may also be exposed.

2,7-Naphthalenediol is a reagent used in the preparation of monomers of high carbon materials. Also used in the synthesis of splitomicin analogues.

Used in hair dyes and organic intermediates