NAPHTHOL YELLOW S Property

Melting point:

>300℃

storage temp. 

Room Temperature

solubility 

Acetonitrile (Slightly), DMSO (Slightly)

Colour Index 

10316

color 

Light Yellow to Dark Yellow

Merck 

14,6393

BRN 

2708476

Stability:

Stable. Incompatible with strong oxidizing agents.

EPA Substance Registry System

C.I. Acid Yellow 1 (846-70-8)

Safety

Hazard Codes 

Xi,C,F

Risk Statements 

11-34

Safety Statements 

22-24/25-45-36/37/39-26-16

WGK Germany 

3

RTECS 

QK1813000

Hazard Note 

Irritant

TSCA 

Yes

HS Code 

32129000

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Warning

Hazard statements

H317May cause an allergic skin reaction

H373May cause damage to organs through prolonged or repeated exposure

Precautionary statements

P280Wear protective gloves/protective clothing/eye protection/face protection.

P302+P352IF ON SKIN: wash with plenty of soap and water.

P314Get medical advice/attention if you feel unwell.

NAPHTHOL YELLOW S Chemical Properties,Usage,Production

Chemical Properties

light yellow powder

Uses

Naphthol Yellow S Hydrate is used in methods for dying of textiles.

Uses

Dye for wool, silk.

Definition

ChEBI: An organic sodium salt that is the disodium salt of 5,7-dinitro-8-hydroxynaphthalene-2-sulfonic acid.

Preparation

4-Hydroxynaphthalene-1,3,6-trisulfonic acid or 1-Naphthol-4,7-disulfonic acid?or 1-Naphthol-2,7-disulfonic acid?or more of the latter with the nitro compounds and nitric acid reaction.

Properties and Applications

colourful green light yellow. Soluble in cold water and hot water yellow, in 0 ℃ when solubility of 8%, slightly soluble in alcohol. Meet strong sulfuric acid is green light yellow, diluted colored light become weak. Its water solution to join sodium hydroxide have floc; Join chloride-ferric chloride solution from yellow to become yellow light brown. Apply to wool, polyamide fiber dyeing, coloured paper colourful yellow, the heavy metal salt can be used for printing ink and rubber color. Can also be used for soap, drug, cosmetics, biological and leather dyeing.

Purification Methods

It is a water-soluble greenish yellow powder. The free sulfonic acid can be recrystallised from dilute HCl (m 150o) or AcOH/EtOAc (m 148-149.5o). The disodium salt is then obtained by dissolving the acid in two equivalents of aqueous NaOH and evaporating to dryness and drying the residue in a vacuum desiccator. The sodium salt can be recrystallised from the minimum volume of H2O or from EtOH [Dermer & Dermer J Am Chem Soc 61 3302 1939]. [Beilstein 11 III 542.]