Description

Benzopurpurin 4B is a synthetic, anionic azo dye known for its distinctive red to violet color and strong affinity for cellulose fibers. This compound matters as a critical staining agent and colorimetric indicator in various analytical and industrial processes, valued for its consistent performance and purity. It is primarily needed by manufacturers and laboratories in the textile, biological staining, and analytical chemistry sectors for applications requiring precise color development and detection.

Application

• Biological Staining: Used as a histological stain for plant and animal tissues, particularly for highlighting cellulose and pectin structures.
• Textile Industry: Functions as a direct dye for cotton and other cellulosic fibers, providing a durable color.
• Analytical Chemistry: Serves as a pH indicator and a colorimetric reagent in various titration and detection methods.
• Paper and Pulp Testing: Employed in laboratory tests to assess the degree of polymerization and cellulose content.
• Microscopy: Acts as a contrast agent to improve the visibility of specific cellular components under a microscope.
• Research & Development: Utilized in biochemical and material science research for labeling and tracking purposes.

Basic Information

Product Name	Benzopurpurin 4B
CAS No.	992-59-6
Molecular Formula	C34H26N6Na2O6S2
Molecular Weight	724.78 g/mol
Synonyms	Direct Red 4B; C.I. 23500; C.I. Direct Red 4B; Benzopurpurine 4B; Cotton Red 4B; Direct Red 4BS; 1-Naphthalenesulfonic acid, 3,3'-((3,3'-dimethyl(1,1'-biphenyl)-4,4'-diyl)bis(azo))bis(4-amino-) disodium salt; Congo Red for microscopy
EINECS	213-591-2

Quality Control

Our Benzopurpurin 4B is produced under a stringent quality management system to ensure batch-to-batch consistency and high purity suitable for industrial and laboratory use. Each lot undergoes comprehensive analytical testing, including identification, assay, and impurity profiling. A Certificate of Analysis (COA) detailing all test results is provided with every shipment to guarantee compliance with your specifications.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry, and well-ventilated area at a controlled room temperature (15-25°C). Keep away from incompatible materials and sources of ignition.

Specification

Item	Specification
Appearance	Dark red to brownish-red powder
Identification (IR)	Conforms to structure
Assay (HPLC)	≥ 85.0% (Dye content)
Loss on Drying	≤ 5.0 %
Water Solubility	Freely soluble
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.