Description

Direct Fast Blue Frl is a synthetic, water-soluble direct dye belonging to the azo chemical class, widely recognized for its bright blue hue and excellent substantivity to cellulosic fibers. Its primary value lies in delivering consistent, vibrant coloration with good wash and light fastness properties in demanding industrial applications. This dye is essential for manufacturers in the textile and paper industries seeking reliable and efficient coloring solutions. The product is supplied under the identifier CAS No. 6717-34-6.

Application

Direct Fast Blue Frl is engineered for high-performance dyeing applications where color consistency and fiber affinity are critical. Its key uses include:

• Textile Dyeing: Primary application for dyeing cotton, viscose, rayon, and other cellulosic fibers in exhaust and continuous dyeing processes.
• Paper Coloring: Used for tinting and dyeing paper pulp, specialty papers, and paperboard to achieve uniform blue shades.
• Leather Finishing: Employed in the dyeing of leather goods to provide rich, penetrating blue colors.
• Ink Formulation: Serves as a colorant in the manufacture of certain types of inks, including stamp pad and flexographic inks.
• Biological Staining: Finds application as a histological stain in laboratory settings for microscopic analysis.

Basic Information

Product Name	Direct Fast Blue Frl
CAS No.	6717-34-6
Molecular Formula	C₃₂H₂₀N₆Na₂O₁₀S₂
Molecular Weight	774.65 g/mol
Synonyms	Direct Blue 71; C.I. 34140; Amanil Sky Blue FRLL; Atul Direct Sky Blue FR; Benzo Sky Blue FRLL; Chloramine Sky Blue FRLL; Direct Fast Blue FRL; Direct Sky Blue FRLL; Sirius Supra Blue FRLL; Solophenyl Blue FRLL
EINECS	229-772-5

Quality Control

Every batch of Direct Fast Blue Frl is manufactured under a strict quality management system and subjected to comprehensive analytical testing. Our quality protocols ensure the product meets consistent standards for shade, strength, solubility, and impurity profiles critical for industrial reproducibility. Certificates of Analysis (COA) documenting key parameters such as purity, hue, and fastness properties are available upon request to support your quality assurance processes.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry, and well-ventilated area at ambient temperature (15-25°C). Keep away from strong oxidizing agents and incompatible materials. The original container is the best storage vessel to maintain product integrity.

Specification

Item	Specification
Appearance	Blue to Bluish-Gray Powder
Identification (IR)	Conforms to Standard
Assay (Color Strength)	≥ 98%
Moisture Content	≤ 5.0%
Water Solubility	Conforms
Shade	Conforms to Standard
Fastness Properties (Typical)	Light: 5-6; Wash: 3-4

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