Description

Acid Brown 21 (CAS No. 61724-04-7) is a high-performance acid dye specifically engineered for the coloration of protein fibers. This product matters for its ability to deliver consistent, vibrant brown shades with excellent leveling properties and good wet fastness. It is a critical component for manufacturers in the textile and leather industries seeking reliable and reproducible dyeing results for materials such as wool, silk, and nylon.

Application

• Textile Dyeing: Primary application for dyeing wool, silk, and polyamide (nylon) fibers to achieve uniform brown hues.
• Leather Finishing: Used in the coloration of leather goods, providing rich and durable brown tones.
• Paper Staining: Suitable for specialty paper products requiring colorfast brown pigmentation.
• Ink Formulation: A component in the manufacture of inks for specific printing applications.
• Biomaterial Staining: Potential use in laboratory settings for histological staining of protein-based tissues.

Basic Information

Product Name	Acid Brown 21
CAS No.	61724-04-7
Molecular Formula	C22H14N6Na2O9S2
Molecular Weight	648.49 g/mol
Synonyms	Acid Brown 2R; C.I. Acid Brown 21; Acid Leather Brown 2R; Acidol Brown 2R; Amido Brown 2R; Dermacid Brown 2R; Lissamine Brown 2R; Supranol Brown 2R; Tectilon Brown 2R; Nylomine Brown C-2R; C.I. 17680; Acid Fast Brown 2R
EINECS	262-967-8

Quality Control

Our Acid Brown 21 is manufactured under a strict quality management system. Every batch undergoes comprehensive analytical testing to ensure it meets precise specifications for dye content, shade, solubility, and fastness properties. A Certificate of Analysis (COA) detailing purity, strength, and key physical-chemical parameters is provided to guarantee batch-to-batch consistency and performance reliability for your industrial processes.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry, and well-ventilated area at room temperature (15-25°C). Keep away from incompatible materials and sources of ignition. This material is light-sensitive (store away from light).

Specification

Item	Specification
Appearance	Brown powder or granules
Identification (IR)	Conforms to standard
Assay (Dye Content)	≥ 95%
Moisture Content	≤ 5.0%
Water Solubility	Conforms
Shade	Conforms to standard pattern
Fastness Properties	To be specified per grade

Note: Specifications can be tailored. Please contact us for the detailed technical data sheet of a specific grade.