Description

Direct Yellow 133 is a high-performance, water-soluble azo dye belonging to the direct dye class, widely recognized for its strong affinity to cellulosic fibers. Its primary value lies in providing excellent light and wash fastness properties, delivering vibrant and consistent yellow shades in demanding industrial applications. This product is essential for manufacturers in the textile, paper, and leather industries seeking reliable and efficient coloring solutions for their production processes.

Application

Direct Yellow 133 is engineered for high-performance coloration across several key industrial sectors. Its primary applications include:

• Textile Dyeing: Exhaust dyeing of cotton, viscose, rayon, and other cellulosic fibers for apparel, home textiles, and industrial fabrics.
• Paper Coloring: Mass coloration and surface coating of paper and paperboard products, including specialty papers and packaging materials.
• Leather Finishing: Dyeing of leather goods, providing uniform penetration and good fastness properties for footwear, garments, and upholstery.
• Ink Formulation: Used as a colorant in the manufacture of inks for flexographic, gravure, and other printing applications.
• Biological Staining: Potential use as a histological stain in laboratory settings for microscopic analysis.

Basic Information

Product Name	Direct Yellow 133
CAS No.	60202-36-0
Molecular Formula	C29H19N5Na2O8S2
Molecular Weight	695.66 g/mol
Synonyms	Direct Fast Yellow 7G; Direct Yellow 7G; C.I. Direct Yellow 133; Direct Yellow 7GL; Amanil Fast Yellow 7G; Atul Direct Fast Yellow 7G; Pyrazol Yellow FG; Sirius Supra Yellow 7G; Solar Fast Yellow 7G; Solophenyl Yellow 7GL
EINECS	262-135-8

Quality Control

Our production of Direct Yellow 133 adheres to stringent quality management protocols to ensure batch-to-batch consistency and performance reliability. Every lot undergoes comprehensive analytical testing, including spectrophotometric analysis for strength and shade, HPLC for purity profile, and standardized application tests for fastness properties. Certificates of Analysis (COA) detailing all relevant specifications are provided with each shipment 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. The product is hygroscopic (moisture-sensitive); ensure containers are sealed after each use to prevent moisture absorption and caking.

Specification

Item	Specification
Appearance	Yellow to Brownish-Yellow Powder
Identification (IR)	Conforms to Standard
Color Strength	100 ± 3% (vs. Standard)
Shade	Conforms to Standard
Moisture Content	≤ 5.0%
Water Insoluble Matter	≤ 0.5%
pH (1% Solution)	6.0 - 8.0
Fastness Properties (Typical)	Light: 5-6; Wash: 4-5

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