Description

4-Hydroxynaphthalene-2-Sulphonic Acid is a key organic intermediate and sulfonating agent, valued for its ability to introduce both hydroxyl and sulfonic acid functional groups into target molecules. This compound is essential for synthesizing a range of high-value chemicals, including dyes, pigments, and optical brighteners. It is a critical raw material for manufacturers in the fine chemical, specialty dye, and agrochemical industries seeking to develop products with specific solubility and chromophoric properties.

Application

• Dye and Pigment Intermediate: A crucial building block for the synthesis of azo dyes, acid dyes, and lake pigments, contributing to color strength and water solubility.
• Optical Brightener Production: Used in the manufacture of stilbene-based optical brightening agents (OBAs) for paper, textiles, and detergents.
• Agrochemical Synthesis: Serves as an intermediate in the production of certain herbicides and plant growth regulators.
• Pharmaceutical Intermediate: Employed in the synthesis of specific active pharmaceutical ingredients (APIs) and diagnostic agents.
• Chemical Research & Development: Utilized in organic synthesis laboratories for introducing sulfonic acid groups into naphthalene-based structures.
• Corrosion Inhibitor Formulation: Acts as a component in specialty formulations designed to protect metal surfaces.

Basic Information

Product Name	4-Hydroxynaphthalene-2-Sulphonic Acid
CAS No.	3771-14-0
Molecular Formula	C₁₀H₈O₄S
Molecular Weight	224.23 g/mol
Synonyms	2-Naphthol-4-sulfonic Acid; 4-Hydroxy-2-naphthalenesulfonic Acid; 2-Hydroxy-5-naphthalenesulfonic Acid; NW Acid; 1,6-Cleve's Acid; 4-Hydroxynaphthalene-2-sulfonic Acid; 4-Hydroxy-2-naphthalenesulphonic Acid; 4-Hydroxy-2-naphthalenesulphonic Acid
EINECS	223-231-2

Quality Control

Our 4-Hydroxynaphthalene-2-Sulphonic Acid is produced under a strict quality management system. Every batch undergoes rigorous analytical testing to ensure it meets precise specifications for purity, identity, and impurity profiles. Certificates of Analysis (COA) documenting results from HPLC, titration, and spectroscopic methods are available for each shipment to guarantee traceability and compliance with your quality requirements.

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 sealed to prevent absorption of atmospheric moisture. Keep away from strong bases and oxidizing agents.

Specification

Item	Specification
Appearance	Off-white to light brown crystalline powder
Identification (IR)	Conforms to structure
Assay (HPLC)	≥ 98.0%
Loss on Drying	≤ 2.0%
Sulfated Ash	≤ 0.5%
Heavy Metals (as Pb)	≤ 20 ppm

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