Description

C.I.Direct Yellow 40 is a substantive azo dye belonging to the direct dye class, valued for its strong affinity to cellulosic fibers without the need for a mordant. Its primary commercial value lies in providing a bright, cost-effective yellow coloration with good wash fastness properties. This product is essential for manufacturers in the textile, paper, and leather industries seeking reliable and consistent dyeing performance.

Application

• Textile Dyeing: Primarily used for dyeing cotton, viscose, rayon, and other cellulosic fibers to achieve vibrant yellow shades.
• Paper Coloring: Applied in the production of colored papers, tissues, and paperboard where a stable yellow hue is required.
• Leather Finishing: Used for dyeing leather goods, providing good penetration and color uniformity.
• Ink Formulation: Serves as a colorant in the manufacture of certain types of inks for specialized applications.
• Biological Staining: May be utilized in specific histological or microbiological staining protocols as a contrast agent.

Basic Information

Product Name	C.I. Direct Yellow 40
CAS No.	12217-72-0
Molecular Formula	C29H19N5Na2O7S2
Molecular Weight	675.61 g/mol
Synonyms	Direct Yellow 40; C.I. 29045; Direct Fast Yellow 5G; Sirius Supra Yellow 5G; Direct Yellow 5G; Direct Yellow G; Benzo Fast Yellow 5GL; Pontamine Fast Yellow 5GL; Aizen Direct Fast Yellow 5GL; Solar Flavine 5G; Direct Yellow 40 (C.I. 29045)
EINECS	Contact for details

Quality Control

Our C.I. Direct Yellow 40 is manufactured under a stringent quality management system to ensure batch-to-batch consistency and performance reliability. Each lot is tested against key parameters including color strength, shade, solubility, and impurity profile. A Certificate of Analysis (COA) detailing specific test results is provided with every shipment to guarantee compliance with your technical 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 light-sensitive (store away from light).

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	Contact for details

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