Acid red 1

Acid Red 1 (CAS 3734-67-6), also known commercially as Red 2G and E128, is a synthetic azo dye used to impart bright red coloration across a range of industrial and formerly food-related applications. It functions as an anionic colorant with strong affinity for protein and polyamide substrates, making it a practical choice for dye bath and solution-based coloring processes.

In textile dyeing, this compound is applied to wool, silk, and nylon fabrics to achieve consistent, level red shades with good wash performance. Leather processors use it in finishing baths to produce uniform surface color on tanned hides. In printing inks and packaging applications, it contributes to red and pink tones in water-based ink formulations. Coatings and adhesive formulators incorporate it where solution-stable red coloration is required in aqueous systems.

The product is supplied as a fine powder or granule, typically in commercial dye grades suited to textile and industrial use. Standard offerings are characterized by dye content specifications rather than pharmacopeial grades. Purity levels are commonly expressed as a percentage of active colorant. Packaging ranges from small technical quantities to bulk industrial supply, ensuring flexibility for various manufacturing scales and requirements.