Description

Vat Yellow 4 CAS NO 128-66-5 is a high-performance vat dye belonging to the anthraquinone chemical class, renowned for its excellent color fastness and light stability. This compound is a critical component for achieving durable and vibrant yellow shades in demanding industrial applications. It is primarily utilized by manufacturers in the textile, leather, and specialty coatings industries seeking superior wash and light resistance.

Application

• Textile Dyeing: Primary application for dyeing cotton, linen, viscose, and other cellulosic fibers to produce fast yellow colors.
• Leather Finishing: Used in the dyeing of leather goods where color durability and resistance to rubbing are essential.
• Industrial Coatings: Employed as a colorant in specialty paints and coatings requiring high chemical and UV stability.
• Paper Coloration: Suitable for high-grade paper products where color consistency and lightfastness are required.
• Pigment Manufacturing: Serves as a key intermediate or colorant in the production of organic pigments.
• Technical Plastics: Used for coloring certain engineering plastics where heat stability is a factor.

Basic Information

Product Name	Vat Yellow 4
CAS No.	128-66-5
Molecular Formula	C28H12N2O4
Molecular Weight	440.41 g/mol
Synonyms	C.I. Vat Yellow 4; C.I. 59100; Indanthren Yellow 4G; Flavanthrone; Flavanthrene Yellow; Pyranthrone; 8,16-Pyranthrenedione; Vat Yellow GX
EINECS	204-903-5

Quality Control

Our Vat Yellow 4 is manufactured under a strict quality management system to ensure batch-to-batch consistency and purity. Each lot is tested against stringent in-house specifications, which typically include parameters for color strength, shade, particle size distribution, and impurity profile. A Certificate of Analysis (COA) detailing these 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 Orange Powder
Identification (IR)	Conforms to Standard
Color Strength	100 ± 3% (vs. Standard)
Shade	Within Agreed Tolerance
Purity (HPLC)	≥ 96.0%
Moisture Content	≤ 1.0%
Ash Content	≤ 0.5%
Particle Size (Passing 80 mesh)	≥ 95%

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