Description

4,4'-Diaminostilbene Dihydrochloride is an important organic intermediate and fluorescent whitening agent precursor. This compound matters for its ability to absorb ultraviolet light and re-emit it as visible blue light, making it a key component in the production of optical brighteners for various industries. It is primarily needed by manufacturers in the textile, paper, detergent, and plastics sectors to enhance the brightness and whiteness of their products.

Application

• Primary raw material for the synthesis of Diarylpyrazoline and Distyrylbiphenyl-type fluorescent whitening agents (FWAs).
• Used in the production of optical brighteners for the textile industry, applied to cotton, nylon, and other fibers.
• Key ingredient in brightening agents for the paper and pulp industry to achieve high-grade whiteness.
• Component in detergent formulations to impart a "whiter-than-white" appearance to laundered fabrics.
• Intermediate in the manufacture of brighteners for plastics and synthetic polymers.
• Used in research and development of novel fluorescent dyes and probes for analytical chemistry.
• Potential intermediate in the synthesis of certain pharmaceutical compounds and liquid crystal materials.

Basic Information

Product Name	4,4'-Diaminostilbene Dihydrochloride
CAS No.	54760-75-7
Molecular Formula	C14H16Cl2N2
Molecular Weight	283.20 g/mol
Synonyms	DAS Dihydrochloride; 4,4'-Diamino-2,2'-stilbenedicarboxylic Acid Dihydrochloride (common misnomer); trans-4,4'-Diaminostilbene Dihydrochloride; 1,1'-(1,2-Ethenediyl)bis[4-aminobenzene] Dihydrochloride; 4,4'-Diaminodiphenylethylene Dihydrochloride; Brightener Intermediate DAS·2HCl; Fluorescent Brightener 199 Intermediate; Blankophor BSU Type Intermediate
EINECS	259-356-7

Quality Control

Our 4,4'-Diaminostilbene Dihydrochloride is manufactured under a strict quality management system. Each batch undergoes rigorous analytical testing to ensure it meets precise specifications for purity, identity, and performance. Certificates of Analysis (COA) detailing key parameters such as assay, impurity profile, and physical characteristics are available upon request to support your quality assurance protocols.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry, and well-ventilated place at room temperature (15-25°C). Due to its hygroscopic nature, the container must be kept tightly sealed to prevent moisture absorption, which can affect product stability and performance. Keep away from incompatible materials.

Specification

Item	Specification
Appearance	Yellow to light yellow crystalline powder
Identification (IR)	Conforms to structure
Assay (HPLC)	≥ 98.0%
Loss on Drying	≤ 1.0%
Residue on Ignition	≤ 0.5%
Heavy Metals (as Pb)	≤ 20 ppm
Related Substances (HPLC)	Individual impurity ≤ 0.5%; Total impurities ≤ 2.0%

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