Description

C.I. Acid Yellow 166 is a synthetic organic dye belonging to the azo chemical class, valued for its bright, stable yellow hue and good fastness properties. This high-performance colorant is engineered to deliver consistent, reliable coloration in demanding industrial applications. It is primarily utilized by manufacturers in the textile, leather, and paper industries seeking durable and vibrant dyeing solutions.

Application

• Primary dyeing and printing of polyamide (nylon) fibers and fabrics.
• Coloration of leather goods, providing good penetration and fastness.
• Dyeing of paper and specialty paper products.
• Used in the formulation of inks for various marking and printing applications.
• Potential use in the coloration of anodized aluminum.
• As a colorant for certain types of plastics and polymers.

Basic Information

Product Name	C.I. Acid Yellow 166
CAS No.	12220-86-9
Molecular Formula	C26H18N4Na2O8S2
Molecular Weight	624.55 g/mol
Synonyms	Acid Yellow 166; C.I. 14167; Acid Leather Yellow N-2R; Acid Fast Yellow E-2G; Nylosan Yellow E-2R; Telon Yellow K-2G; Supranol Yellow GG; Acid Yellow 2G
EINECS	Contact for details

Quality Control

Our production of C.I. Acid Yellow 166 adheres to stringent quality management protocols to ensure batch-to-batch consistency and performance reliability. Every lot is tested against key parameters including color strength, shade, solubility, and fastness properties. A comprehensive Certificate of Analysis (COA) detailing purity, physical properties, and performance metrics is 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 room temperature (15-25°C). Keep away from strong oxidizing agents.

Specification

Item	Specification
Appearance	Yellow to orange powder
Identification (IR)	Conforms to standard
Color Strength	100 ± 3% (vs. Standard)
Moisture Content	≤ 5.0%
Water Insoluble Matter	≤ 1.0%
pH (1% Solution)	6.0 - 8.0
Shade	Conforms to standard
Fastness Properties	To be specified per grade

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