Description

Acid Red 137 is a synthetic, water-soluble azo dye belonging to the acid dye class, known for its bright red hue and good fastness properties. This high-performance colorant is valued for its ability to produce vibrant and consistent shades on protein-based fibers like wool, silk, and nylon. It is a critical component for manufacturers in the textile, leather, and paper industries seeking reliable and efficient dyeing solutions. The compound is supplied as a high-purity powder to ensure optimal performance in demanding industrial applications.

Application

• Textile Dyeing: Primary application for dyeing wool, silk, and polyamide (nylon) fibers, providing excellent color yield and wash fastness.
• Leather Coloring: Used in the dyeing of leather goods, offering rich, penetrating color for products like upholstery, apparel, and accessories.
• Paper Staining: Employed to color specialty papers, including decorative and packaging materials, where a bright red shade is required.
• Ink Formulation: Serves as a colorant in the manufacture of inks for various printing applications.
• Biological Staining: Potential use as a histological stain in laboratory settings for microscopic analysis.
• Polymer Coloring: Can be incorporated into certain synthetic polymers and plastics during manufacture.

Basic Information

Item	Detail
Product Name	Acid Red 137
CAS No.	6222-63-5
Molecular Formula	C22H14N4Na2O7S2
Molecular Weight	556.48 g/mol
Synonyms	Acid Red 137; C.I. 18055; Acid Leather Red BG; Naphthalene Red BG; Acid Fast Red BG; Azo Rubine; Acid Brilliant Red 3B; C.I. Acid Red 137; 6-Hydroxy-5-[(2-methoxy-5-methyl-4-sulfophenyl)azo]-2-naphthalenesulfonic acid disodium salt
EINECS	228-314-8

Quality Control

Every batch of Acid Red 137 is manufactured under a strict quality management system. We perform comprehensive in-process and final testing to ensure the product meets precise specifications for color strength, shade, solubility, and impurity profiles. A Certificate of Analysis (COA) detailing purity, physical properties, and performance characteristics is provided with each shipment to guarantee consistency and traceability for our global B2B clients.

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). Due to its hygroscopic (moisture-sensitive) nature, the container must be kept tightly sealed after initial use to prevent absorption of atmospheric moisture, which can affect performance.

Specification

Item	Specification
Appearance	Red to dark red powder
Identification (IR)	Conforms to standard
Assay (HPLC)	≥ 95.0%
Color Strength	100 ± 3% (vs. Standard)
Moisture Content	≤ 5.0%
Water Solubility	Clear solution at 1%
Ash Content	≤ 30.0%
Heavy Metals (as Pb)	≤ 20 ppm

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