Description

Acid Yellow 25 (C.I. 18835) is a synthetic anionic azo dye belonging to the acid dye class, identified by CAS NO 6359-85-9. It is valued for its bright, clear yellow hue and good affinity for protein-based and polyamide fibers. This dye is primarily required by manufacturers in the textile, leather, and paper industries for coloration processes, and is also utilized in specialized applications such as biological staining and ink formulations.

Application

• Textile Dyeing: Primary application for dyeing wool, silk, and nylon fibers to achieve a bright yellow shade.
• Leather Coloring: Used in the dyeing of leather goods, providing good penetration and color fastness.
• Paper Staining: Employed in the production of colored papers and paper products.
• Biological Stains: Serves as a histological stain in laboratory settings for microscopic analysis.
• Ink Manufacturing: A colorant component in the formulation of certain inks, including ballpoint pen inks.
• Wood Staining: Applied for coloring wood and wood-based materials.
• Soap and Detergent Coloring: Used to impart color to soaps and cleaning products.

Basic Information

Product Name	Acid Yellow 25
CAS No.	6359-85-9
Molecular Formula	C16H13N4NaO4S
Molecular Weight	380.35 g/mol
Synonyms	C.I. Acid Yellow 25; C.I. 18835; Acid Leather Yellow D; Acid Fast Yellow E; Acid Yellow E; Wool Yellow 2G; Lissamine Yellow 2G; Acid Yellow 2G; 2,5-Dichloro-4-[4-[(2,5-dichlorophenyl)azo]-3-methyl-5-oxo-1H-pyrazol-1-yl]benzenesulfonic Acid Sodium Salt; Aizen Acid Yellow E; Kiton Yellow 2G
EINECS	228-785-6

Quality Control

Our Acid Yellow 25 is manufactured under a strict quality management system to ensure batch-to-batch consistency and performance. Each lot is tested against key parameters including color strength, shade, solubility, and impurity profile. Certificates of Analysis (COA) documenting these results 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. The product is light-sensitive (store away from light).

Specification

Item	Specification
Appearance	Yellow to orange-yellow powder
Identification (IR)	Conforms to standard
Assay (HPLC)	≥ 95.0%
Color Strength	100 ± 3% (vs. Standard)
Shade	Conforms to standard
Moisture Content	≤ 5.0%
Water Solubility	Conforms
Ash Content	≤ 1.0%

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