Description

Direct Red 75 Tetrasodium Salt is a high-purity, water-soluble anionic dye belonging to the azo dye class. This compound is valued for its strong, bright red color and excellent substantivity to cellulosic fibers, making it a critical component in industrial dyeing and printing processes. It is primarily utilized by manufacturers in the textile, paper, leather, and ink industries seeking reliable and consistent colorants for their products.

Application

• Textile Dyeing: Primary application for dyeing cotton, viscose, and other cellulosic fibers to achieve vibrant red shades.
• Paper Coloring: Used in the production of colored papers, tissues, and paperboard where lightfastness is required.
• Leather Finishing: Imparts color to leather goods in the tanning and finishing stages.
• Ink Formulation: Serves as a colorant in the manufacture of inks for various printing applications.
• Biological Staining: Potential use as a histological stain in laboratory settings.
• Specialty Coatings: Incorporated into coatings and paints where specific color properties are needed.

Basic Information

Product Name	Direct Red 75 Tetrasodium Salt
CAS No.	2829-43-8
Molecular Formula	C32H20N7Na4O13S4
Molecular Weight	990.79 g/mol
Synonyms	Direct Red 75; C.I. Direct Red 75; Direct Fast Scarlet 4BS; Tetrasodium 8-[[4-[[2,4-Diamino-5-[(4-sulfophenyl)azo]phenyl]azo]-1-naphthyl]azo]-1,3,6-naphthalenetrisulfonate; Pontamine Fast Scarlet 4BS; Sirius Scarlet 4BS; Amanil Fast Scarlet 4BS; Azo Rubine S
EINECS	220-593-1

Quality Control

Our Direct Red 75 Tetrasodium Salt is manufactured under a stringent quality management system. Each batch undergoes comprehensive analytical testing to ensure it meets precise specifications for color strength, hue, solubility, and impurity profiles. Certificates of Analysis (COA) documenting purity, physical properties, and conformance to agreed specifications are available upon request.

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 the container is kept tightly sealed to prevent absorption of atmospheric moisture, which can affect performance.

Specification

Item	Specification
Appearance	Dark red to brown powder
Identification (IR)	Conforms to standard
Assay (Color Strength)	≥ 95%
Moisture Content	≤ 5.0%
Water Solubility	Clear solution
pH (1% Solution)	7.0 - 9.0
Ash Content	≤ 30%

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