Vat Yellow 2

Vat Yellow 2 Appearance is orange powder, insoluble in water and alcohol. It is yellow in concentrated sulfuric acid. The leuco body formed by the dye in the alkaline powder solution is purple, and the acid powder solution is dark orange.

Vat Yellow 2 is Orange powder, insoluble in water and ethanol. In alkaline insurance powder also in stock for purple; In the acidic insurance powder also in dark orange ones for; The strong sulfuric acid to yellow.

TRADE NAME:Vat Yellow 2GCN,Vat Yellow GCN,Vat Brilliant Yellow 2GC,Intravat Yellow GC,Nihonthrene Yellow GCN

Key features

• Class: Vat dye — requires reduction (vatting) and subsequent oxidation to fix color
• Excellent washfastness — suitable for high-performance, hard-wearing textiles
• High lightfastness — maintains hue under prolonged exposure
• Low bleeding and migration — stable in multi-component dyeings and blends
• Good alkali and chlorine tolerance compared with many direct dyes
• Produces clean, bright yellow shade with good depth and tinting strength
• Compatible with standard vat dyeing processes for cotton and other cellulosics
• Forms level, even shades when properly dispersed and reduced
• Available in granular/powder form for industrial dyehouse handling

Technical Specifications

• ‍CAS NO: 129-09-9
• CI.NO: 67300
• Molecular Formula: C28H14N2O2S2
• Molecular Weight: 474.56
• Shade: Green light yellow‍

Application Features

Colour Fastness Test

Application:

Vat Yellow 2 Mainly used for cotton, silk sheets, towels and the monochrome printing. Can also be used for viscose, polyester/cotton,PVA/cotton blended fabric dyeing and printing, and can also be used for the paper dyeing.

Use condition:

• ‍1.Vat Yellow 2(Vat yellow GCN) For the dyeing or dip dyeing of cotton products, it is applicable to method A. When color matching, it can also obey other main color dyes, using B or C method. The drying time of dry cylinder is 15~20min, and the reduction temperature is 55~60°C. The dry cylinder stabilization time is 30~40min. The dry cylinder temperature can also be increased to 70~75°C.
• 2.The leuco body has good affinity and leveling property to cotton fiber. The dyeing curve is shown in Fig. 4-5-2. The hiding power of dead cotton is still good, and the leuco body is sensitive to light. Washed and oxidized, and fully soaped. Soaping conditions should be controlled at near boiling point and kept for 2~3min. If the temperature of soap is around 80°C, the treatment time should be kept for about 10min to help fully develop color. Sodium oxidizes to develop color, and the color of the reduced vat yellow GCN is darker.
• 3.Vat yellow 2 has serious brittleness. Generally, monochromatic color should only be dyed in light color (about 0.3%), which is mainly used for dyeing green. In order to ensure the best fastness, when color matching with reduced blue GCDN, The amount of vat yellow GCN should not exceed 50% of blue GCDN; when color matching with reduced blue BCS, the amount of yellow GCN should not exceed 20% of blue BCS; when it is combined with reducing brilliant green FFB, B, 2G, the dosage should be more lesser.
• 4.Vat yellow 2 can be used for dyeing of viscose fiber, vinylon, etc. If the cotton blended fabric is dyed by suspension padding, a uniform color can be obtained.
• 5.It is rarely used in direct printing of cotton fabrics. It is only suitable for light color when used for discharge printing. Pre-reduction method is used for reduction of yellow GCN printing paste, caustic soda as alkali agent, pre-reduction temperature is 60 °C, and should be heated to 60 ° C after adding the insurance powder, and then kept for 30 minutes, and then add white powder when it is used.
• 6.It printing and dyeing fabrics are finished with BHES resin, and the color is dimmed.‍

Precautions

• ‍‍1.Vat yellow 2 has serious light brittleness, so it is generally not suitable for use as a primary color. When used for color matching, the amount should be properly controlled.
• 2. It should be stored in a dry, ventilated place to avoid moisture.

FAQ

What fibers are best dyed with Vat Yellow 2?

Vat Yellow 2 is optimized for cellulosic fibers such as cotton, viscose and lyocell. It is not typically used for nylons or most polyesters without special carriers or high-temperature processes.

How is Vat Yellow 2 applied in a commercial dyehouse?

Vat dyes are applied by reducing the dye to its soluble leuco form under alkaline/reducing conditions, padding or exhausting the fiber with the leuco solution, then oxidizing to regenerate the insoluble dye inside the fiber. Maintain good dispersion before reduction and control oxidation to prevent spotting.

How can I improve shade consistency when using Vat Yellow 2?

Key controls are consistent liquor ratio, pre-dispersing the dye evenly, stable pH/temperature during reduction, and a uniform oxidation stage. Use well-dispersed slurries and avoid localized overdosing; perform lab trials for shade matching before production scale-up.

Is Vat Yellow 2 compatible with other dye classes in piece goods?

Vat Yellow 2 is often used alongside other vat dyes for fastness-matched palettes. Compatibility with reactive or direct dyes is limited because vat dyes require different chemistry (reduction/oxidation). For multi-class color recipes, plan process sequencing and fixation to avoid cross-interaction.

What handling and storage precautions should we follow?

Store in a cool, dry place away from strong oxidizers. Use dust controls when handling powdered product and personal protective equipment (gloves, mask) to avoid inhalation. Keep containers tightly closed to prevent moisture uptake and caking.

Are there environmental or wastewater considerations for Vat Yellow 2?

Vat dye processes involve reducing agents and strong alkali which affect wastewater chemistry. Ensure proper treatment for sulfides or reducing residues, monitor BOD/COD and color removal in effluent, and follow local discharge regulations. Process optimization (lower liquor ratio, efficient oxidation) reduces load.

Can Vat Yellow 2 be used in printing inks or as a pigment substitute?

Vat Yellow 2 is primarily a dye for fiber applications; converting it into a pigment-like form requires chemical treatment and micronization. For printing systems, evaluate dispersion stability and binder compatibility; consult technical support for formulation guidance.

What troubleshooting steps help with specks or unevenness?

Check dye dispersion quality and reduce particle agglomerates before vatting. Ensure adequate wetting agents and proper de-aeration during padding or exhaustion. Slow, controlled oxidation and gentle rinsing reduce speck formation.