Description

C.I. Direct Blue 79 is a high-performance, water-soluble disazo direct dye belonging to the copper phthalocyanine class. It is valued for its excellent wash fastness, brilliant blue shade, and strong affinity for cellulosic fibers like cotton and viscose. This dye is essential for manufacturers in the textile industry seeking consistent, vibrant coloration with good overall fastness properties. The compound is identified by CAS No. 12217-55-9.

Application

This direct dye is primarily used for coloring cellulosic materials, offering a range of application benefits:

• Textile Dyeing: Exhaust dyeing of cotton, viscose, rayon, and other regenerated cellulose fibers.
• Paper Coloring: Imparting a stable blue color to various grades of paper and paperboard.
• Leather Finishing: Used in the dyeing of leather goods where a deep blue color is required.
• Ink Formulation: A component in the manufacture of certain types of inks, including stamp pad inks.
• Biological Staining: Employed in specific histological and microbiological staining procedures.

Basic Information

Product Name	C.I. Direct Blue 79
CAS No.	12217-55-9
Molecular Formula	C32H14CuN8O6S2•2Na
Molecular Weight	782.16 g/mol (as disodium salt)
Synonyms	Direct Blue 79; Copper phthalocyanine direct dye; C.I. 23255; Direct Blue 2B; Amanil Sky Blue 2B; Atul Direct Sky Blue 2B; Solophenyl Blue BL; Sirius Supra Blue BRR; Contact for additional trade names.
EINECS	235-406-6

Quality Control

Our production of C.I. Direct Blue 79 adheres to stringent quality management protocols to ensure batch-to-batch consistency and performance reliability. Key parameters such as color strength, shade, solubility, and impurity profiles are rigorously tested against established internal specifications. A Certificate of Analysis (COA) detailing purity, physical properties, and conformance is provided with every shipment.

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). Keep away from strong oxidizing agents. The product is hygroscopic (moisture-sensitive); ensure the container is properly sealed after use to prevent moisture absorption and caking.

Specification

Item	Specification
Appearance	Dark Blue Powder
Identification (IR)	Conforms to Standard
Color Strength	100 ± 3% (vs. Standard)
Shade	Conforms to Standard
Moisture Content	≤ 5.0%
Water Solubility	Conforms
pH (1% Solution)	6.0 - 8.0
Ash Content	≤ 30.0%

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