Description

4-Amino-5-Hydroxynaphthalene-1,3-Disulphonic Acid is a key aromatic sulfonic acid derivative and a vital intermediate in the synthesis of complex organic dyes and pigments. Its molecular structure, featuring both amino and hydroxyl groups on a naphthalene disulfonic acid backbone, makes it an essential building block for creating colorants with specific properties. This compound is primarily utilized by manufacturers in the dyestuff, textile, and specialty chemical industries seeking to produce high-performance azo dyes and other functional colorants.

Application

• Primary intermediate in the synthesis of azo dyes and pigments for textiles, leather, and paper.
• Key starting material for producing acid dyes and direct dyes used in wool, silk, and nylon coloring.
• Used in the manufacture of reactive dyes for cellulose fibers like cotton.
• Intermediate for specialty pigments with applications in inks and coatings.
• Potential precursor in the synthesis of fluorescent whitening agents (optical brighteners).
• Used in research and development of novel functional dyes for non-textile applications.
• Intermediate for chemicals used in analytical reagents and biological staining.

Basic Information

Product Name	4-Amino-5-Hydroxynaphthalene-1,3-Disulphonic Acid
CAS No.	82-47-3
Molecular Formula	C₁₀H₉NO₇S₂
Molecular Weight	319.31 g/mol
Synonyms	1,3-Naphthalenedisulfonic acid, 4-amino-5-hydroxy-; 4-Amino-5-hydroxy-1,3-naphthalenedisulfonic acid; 5-Amino-4-hydroxy-1,3-naphthalenedisulfonic acid; 1,3-Naphthalenedisulfonic acid, 5-amino-4-hydroxy-; 4-Amino-5-hydroxynaphthalene-1,3-disulfonic acid; 5-Amino-4-hydroxynaphthalene-1,3-disulfonic acid; H acid (Note: "H acid" typically refers to 1-Amino-8-hydroxynaphthalene-3,6-disulfonic acid, but this is a related positional isomer); Contact for details on specific trade names.
EINECS	201-418-7

Quality Control

Our 4-Amino-5-Hydroxynaphthalene-1,3-Disulphonic Acid is produced under a strict quality management system. Every batch undergoes rigorous analytical testing to ensure consistent purity and performance as a dye intermediate. We provide comprehensive Certificates of Analysis (COA) with each shipment, detailing key parameters such as assay, impurity profile, and physical characteristics. Our quality commitment ensures the reliability and batch-to-batch consistency required for industrial synthesis 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 strong oxidizing agents and incompatible materials. The product may be moisture-sensitive; ensure containers are sealed after use to prevent absorption of atmospheric moisture.

Specification

Item	Specification
Appearance	Off-white to light brown powder or crystals
Identification (IR)	Conforms to structure
Assay (HPLC)	≥ 95.0%
Loss on Drying	≤ 2.0%
Sulfated Ash	≤ 0.5%
Related Substances (HPLC)	Total impurities ≤ 5.0%
Solubility	Soluble in alkaline aqueous solutions

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