Description

Direct Black 19 is a high-performance, substantive azo dye widely used for its deep, rich black shades and excellent fastness properties. Its primary value lies in providing consistent, high-quality coloration with strong affinity for cellulosic fibers, ensuring efficient and economical dyeing processes. This product is essential for manufacturers in the textile, leather, and paper industries seeking reliable and vibrant black dyes for their production lines. The compound is identified by CAS No. 6428-31-5.

Application

• Textile Dyeing: Primary application for dyeing cotton, viscose, and other cellulosic fibers to achieve deep black shades.
• Leather Coloring: Used in the tanning industry for dyeing leather goods, providing uniform and durable color.
• Paper Staining: Employed in the production of colored papers, including specialty and packaging papers.
• Ink Formulation: A key component in the manufacture of inks for various printing applications.
• Wood Staining: Used to impart color to wood and wood-based products.
• Biological Staining (Histology): May be utilized in laboratory settings as a biological stain for microscopic analysis.

Basic Information

Product Name	Direct Black 19
CAS No.	6428-31-5
Molecular Formula	C34H25N9Na2O7S2
Molecular Weight	781.72 g/mol
Synonyms	Direct Black 19; Direct Black G; C.I. 35255; Direct Deep Black EW; Direct Black EX; Benzo Deep Black G; Pontamine Black E; Atul Direct Black G; Azo Black G; Diazol Black G
EINECS	229-181-9

Quality Control

Our Direct Black 19 is manufactured under a stringent quality management system to ensure batch-to-batch consistency and high purity. The product is tested against key parameters including color strength, shade, solubility, and impurity profiles to meet industry specifications. Certificates of Analysis (COA) documenting these results are available for every batch upon request, providing full traceability and quality assurance for your production 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). Due to its hygroscopic (moisture-sensitive) nature, the container must be kept tightly sealed to prevent absorption of atmospheric moisture, which can affect product performance.

Specification

Item	Specification
Appearance	Black to Bluish-Black Powder
Identification (IR)	Conforms
Color Strength	100 ± 3% (Standard)
Shade	Conforms to Standard
Moisture Content	≤ 5.0%
Water Insoluble Matter	≤ 1.0%
pH (1% Solution)	6.0 - 8.0
Fastness Properties	To be specified per grade

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