Description

Disodium 7-Hydroxynaphthalene-1,3-Disulphonate is a high-purity, water-soluble aromatic intermediate essential for the synthesis of dyes, pigments, and optical brightening agents. Its unique molecular structure, featuring both hydroxyl and sulfonate groups, makes it a versatile coupling component and a key building block for creating colorants with specific hue and fastness properties. This compound is critical for manufacturers in the textile, paper, and specialty chemical industries seeking reliable, high-quality intermediates for their production processes.

Application

• Dye and Pigment Intermediate: A primary coupling component in the synthesis of azo dyes and pigments for textiles, leather, and paper.
• Optical Brightener Production: Serves as a key starting material for manufacturing stilbene-based optical brightening agents (OBAs) used in detergents and paper.
• Chemical Synthesis: Utilized as a versatile building block in organic synthesis for creating more complex sulfonated aromatic compounds.
• Research & Development: Employed in laboratory settings for developing new colorants and functional materials.

Basic Information

Product Name	Disodium 7-Hydroxynaphthalene-1,3-Disulphonate
CAS No.	842-19-3
Molecular Formula	C₁₀H₆Na₂O₇S₂
Molecular Weight	348.24 g/mol
Synonyms	7-Hydroxy-1,3-naphthalenedisulfonic acid disodium salt; 1,3-Naphthalenedisulfonic acid, 7-hydroxy-, disodium salt; Disodium 7-hydroxynaphthalene-1,3-disulfonate; 7-Hydroxynaphthalene-1,3-disulfonic acid disodium salt; Acid Chrome Blue K; Naphthol Disulphonate B; Bayer Acid; Chromotropic acid disodium salt
EINECS	212-661-6

Quality Control

Our Disodium 7-Hydroxynaphthalene-1,3-Disulphonate is manufactured under a strict quality management system. Every batch undergoes comprehensive analytical testing, including HPLC for purity and identity confirmation, to ensure it meets exacting specifications for use in sensitive applications like dye and optical brightener synthesis. A Certificate of Analysis (COA) detailing all test results is provided with each shipment to guarantee traceability and compliance.

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). This material is hygroscopic (moisture-sensitive); ensure containers are kept tightly sealed to prevent absorption of atmospheric moisture.

Specification

Item	Specification
Appearance	Off-white to light beige powder
Identification (IR)	Conforms to reference spectrum
Assay (HPLC)	≥ 98.0%
Water Content	≤ 2.0%
pH (1% Solution)	7.0 - 9.0
Heavy Metals (as Pb)	≤ 20 ppm

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