Acid Red 27, also widely known as Amaranth or FD & C Red No.2, is a synthetic anionic dye. Its main constituent is trisodium 2‑hydroxy‑1‑(4‑sulfonato‑1‑naphthylazo)naphthalene‑3,6‑disulfonate. Besides primary color‑giving substances, it contains minor auxiliary color impurities. Sodium chloride and sodium sulfate exist as major non‑colored inorganic salt components within the commercial product. This dye can be further processed into its corresponding aluminum lake form for different application scenarios.
Physically, it presents as dark‑red to dark‑purple fine powder. The material is nearly odor‑free and carries a noticeable salty taste originating from residual inorganic salts. A 1% aqueous solution of this dye shows an approximate pH value of 10.8. When applied under acid‑dyeing bath conditions, it can produce vivid bluish‑red shades on wool and silk substrates. It delivers good dye uptake for protein fibers and generates bright, uniform color tones on these textile materials.
Acid Red 27 Chemical Properties |
Melting point | >300°C |
density | 1.5 |
Fp | 214° |
storage temp. | Sealed in dry,Room Temperature |
solubility | H2O: soluble10mg/mL |
form | Crystalline Powder |
Colour Index | 16185 |
color | Dark reddish-brown to dark brown |
PH | 9.65 (28°C, - OECD Test Guideline 122 - alkaline) |
Water Solubility | 50 g/L (20 ºC) |
λmax | 520 nm |
Merck | 14,375 |
BRN | 4122311 |
Stability: | Stable. Incompatible with strong oxidizing agents. |
Biological Applications | Detecting membrane-potential change; treating acquired resistance to GABAergic (ARG) agents |
Major Application | cleaning products |
Cosmetics Ingredients Functions | HAIR DYEING |
InChIKey | WLDHEUZGFKACJH-ZRUFZDNISA-K |
SMILES | [Na+].[Na+].[Na+].Oc1c(N=Nc2ccc(c3ccccc23)S([O-])(=O)=O)c4ccc(cc4cc1S([O-])(=O)=O)S([O-])(=O)=O |
LogP | -5.13 |
CAS DataBase Reference | |
IARC | 3 (Vol. 8, Sup 7) 1987 |
EPA Substance Registry System | C.I. Acid Red 27, trisodium salt (915-67-3) |
Safety Information |
Hazard Codes | Xi |
Risk Statements | 36/37/38 |
Safety Statements | 36/37/39-26 |
WGK Germany | 3 |
RTECS | QJ6550000 |
TSCA | TSCA listed |
HS Code | 32129000 |
Storage Class | 11 - Combustible Solids |
Hazard Classifications | Eye Irrit. 2 |
Hazardous Substances Data | 915-67-3(Hazardous Substances Data) |
Toxicity | LD50 intraperitoneal in mouse: 1gm/kg |
Acid Red 27, also named Amaranth, is a versatile anionic acid dye with multi‑scenario usability. It achieves brilliant bluish‑red coloration for wool and silk substrates within acid dye bath environments. It shows favorable affinity toward protein‑based textile fibers and delivers even, saturated dyeing results on these materials.
Beyond textile dyeing, this substance can serve as a food‑grade colorant for qualified formulations under compliant local regulations. It can also function as a chemical indicator for laboratory analytical work. Moreover, it finds practical usage within the color‑photography industry for relevant imaging‑related processes.
Shipment Lead Time
Stock‑available goods can be dispatched within 2‑3 working days upon order confirmation. For orders requiring fresh manufacturing, the whole production and preparation cycle will take roughly 7‑10 working days before delivery.
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