Description

C.I. Basic Yellow 40 is a synthetic cationic dye belonging to the methine class, widely recognized for its bright and intense yellow hue. This product is valued for its excellent tinctorial strength and good lightfastness, making it a reliable colorant for demanding industrial applications. It serves as a critical component for manufacturers in the textile, paper, and specialty ink industries seeking vibrant, stable coloration.

Application

• Textile Dyeing and Printing: Primarily used for dyeing acrylic fibers, modacrylics, and certain polyesters, providing a bright, wash-fast yellow color.
• Paper Coloring: Employed in the production of colored papers, tissues, and paperboard where a strong, bleed-resistant yellow is required.
• Ink Formulation: A key pigment for specialty inks, including flexographic and packaging inks, due to its color purity and stability.
• Leather Finishing: Used in dyeing leather goods to achieve consistent and vibrant yellow shades.
• Biological Staining: Finds application as a histological stain in laboratory settings for microscopic analysis.
• Plastics and Polymers: Can be incorporated for mass coloration of certain plastics where compatibility is confirmed.

Basic Information

Product Name	C.I. Basic Yellow 40
CAS No.	12221-86-2
Molecular Formula	C21H29N3O3S
Molecular Weight	403.54 g/mol
Synonyms	Basic Yellow 40; Aizen Cathilon Yellow 3GLH; Astrazon Yellow 3GL; Maxilon Yellow 3GL; C.I. 48045; 1-Methyl-2-((1-methyl-2-phenyl-1H-indol-3-yl)azo)-3-(3-sulfopropyl)-3H-benzimidazolium hydroxide, inner salt; Cationic Yellow 40
EINECS	Contact for details

Quality Control

Our C.I. Basic Yellow 40 is manufactured under a strict quality management system. Each batch is tested to ensure consistent strength, shade, and chemical purity against established internal specifications. Certificates of Analysis (COA) documenting key parameters such as color strength, solubility, and impurity profile are available upon request to support your quality assurance protocols.

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.

Specification

Item	Specification
Appearance	Yellow to orange-brown powder
Identification (IR)	Conforms to standard
Color Strength	100 ± 3% (vs. Standard)
Moisture Content	≤ 5.0%
Water Solubility	Clear solution at 1%
Ash Content	≤ 1.0%

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