Description

C.I. Direct Blue 156 is a high-performance, water-soluble direct dye belonging to the azo chemical class. It is valued for its excellent substantivity to cellulosic fibers, providing deep and vibrant blue shades with good overall fastness properties. This dye is essential for manufacturers in the textile industry seeking reliable and efficient coloring solutions for cotton, viscose, and other regenerated cellulose materials. The compound is identified by CAS No. 61724-73-0.

Application

• Textile Dyeing: Primary application for exhaust and continuous dyeing of cotton, rayon, and other cellulosic fabrics.
• Paper Coloring: Used for tinting and dyeing paper products where good water-fastness is required.
• Leather Finishing: Employed in the dyeing of leather goods to achieve uniform blue colors.
• Ink Formulation: A colorant component in the manufacture of certain types of inks.
• Blend Dyeing: Suitable for dyeing blends of cellulose with synthetic fibers like polyester or nylon under specific conditions.

Basic Information

Product Name	C.I. Direct Blue 156
CAS No.	61724-73-0
Molecular Formula	C32H20N6Na4O16S4
Molecular Weight	996.80 g/mol
Synonyms	Direct Blue 156; C.I. 24175; Direct Blue 2B; Direct Blue B2RL; Amanil Sky Blue B; Atul Direct Sky Blue B; Dinamine Sky Blue B; Direct Sky Blue B; Sirius Supra Blue B; Solophenyl Blue BLE
EINECS	262-964-7

Quality Control

Our C.I. Direct Blue 156 is manufactured under strict quality management systems to ensure batch-to-batch consistency and performance reliability. Each production lot undergoes comprehensive analysis, including strength, shade, solubility, and fastness property testing against established industrial benchmarks. A Certificate of Analysis (COA) detailing purity, physical properties, and performance characteristics is provided with every shipment to guarantee it meets your specific application requirements.

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 sealed after each use to prevent moisture absorption and caking.

Specification

Item	Specification
Appearance	Blue to Bluish-Gray Powder
Identification (IR)	Conforms to Standard
Color Strength	100 ± 3% (vs. Standard)
Moisture Content	≤ 5.0%
Water Insoluble Matter	≤ 1.0%
Shade	Conforms to Standard
Solubility in Water	Conforms
Fastness Properties	Typical values available on request

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