Description

C.I. Direct Blue 166 is a synthetic, water-soluble direct dye belonging to the azo chemical class, identified by CAS No. 6599-18-4. It is valued for its strong affinity to cellulosic fibers, providing excellent wash fastness and deep, vibrant blue shades. This dye is essential for industrial operations in the textile, paper, and leather industries requiring consistent, high-quality coloration.

Application

• Textile Dyeing: Primary application for dyeing cotton, viscose, rayon, and other cellulosic fibers.
• Paper Coloring: Used in the production of colored papers, tissues, and paperboard.
• Leather Finishing: Imparts color to leather goods in the tanning industry.
• Ink Formulation: A colorant component for certain types of inks and toners.
• Biological Staining: Potential use as a histological stain in laboratory settings.
• Specialty Applications: Coloring for non-woven fabrics, wood stains, and other industrial materials.

Basic Information

Product Name	C.I. Direct Blue 166
CAS No.	6599-18-4
Molecular Formula	C32H20N6Na4O16S4
Molecular Weight	996.80 g/mol
Synonyms	Direct Blue 166; Direct Blue 2B; C.I. 24220; Amanil Sky Blue 2B; Atul Direct Sky Blue 2B; Direct Sky Blue 2B; Pontamine Sky Blue 2B; Sirius Supra Blue 2B; Solar Sky Blue 2B; Diazol Sky Blue 2B
EINECS	229-562-3

Quality Control

Our C.I. Direct Blue 166 is manufactured under a stringent quality management system. Each batch is tested to ensure consistent strength, shade, and solubility, meeting the specifications required for industrial dyeing processes. A Certificate of Analysis (COA) detailing purity, physical properties, and performance characteristics is provided with every shipment.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry, well-ventilated area at room temperature (15-25°C). Keep away from incompatible materials. The product is light-sensitive (store away from light).

Specification

Item	Specification
Appearance	Blue to Bluish-Grey Powder
Identification (IR)	Conforms to Standard
Assay (Dye Content)	Min. 95%
Moisture Content	Max. 5.0%
Water Insoluble Matter	Max. 0.5%
Shade	Conforms to Standard
Solubility in Water	Conforms

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