4-amino-5-hydroxynaphthalene-1,3-disulphonic acid Property

EPA Substance Registry System

1,3-Naphthalenedisulfonic acid, 4-amino-5-hydroxy- (82-47-3)

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Danger

Hazard statements

H314Causes severe skin burns and eye damage

Precautionary statements

P260Do not breathe dust/fume/gas/mist/vapours/spray.

P264Wash hands thoroughly after handling.

P264Wash skin thouroughly after handling.

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

P301+P330+P331IF SWALLOWED: Rinse mouth. Do NOT induce vomiting.

P303+P361+P353IF ON SKIN (or hair): Remove/Take off Immediately all contaminated clothing. Rinse SKIN with water/shower.

P304+P340IF INHALED: Remove victim to fresh air and Keep at rest in a position comfortable for breathing.

P305+P351+P338IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing.

P310Immediately call a POISON CENTER or doctor/physician.

P321Specific treatment (see … on this label).

P363Wash contaminated clothing before reuse.

P405Store locked up.

P501Dispose of contents/container to..…

4-amino-5-hydroxynaphthalene-1,3-disulphonic acid Chemical Properties,Usage,Production

Chemical Properties

1-Amino-8-hydroxynaphthalene-2,4-disulfonic acid [82-47-3]. (4-amino-5-hydroxynaphthalene-1,3-disulfonic acid), Chicago acid, 2 S acid, C10H9NO7S2, Mr 319.3, and its acid sodium salt are readily soluble in water; the latter can be salted out with sodium chloride. In alkaline solution, coupling with diazo compounds takes place ortho to the hydroxyl group. Alkaline hydrolysis at 170℃ gives 1,8-dihydroxynaphthalene-2,4-disulfonic acid. Heating with dilute sulfuric acid results in desulfonation to give 1-amino-8-hydroxynaphthalene-2-sulfonic acid.

Uses

Chicago acid is used as a coupling component for C.I. Direct Blue 1, C.I. Direct Blue 22, and C.I. Direct Blue 76 (the dicopper complex of demethylated).

Production Methods

A solution of the disodium salt of naphthosultam-2,4-disulfonic acid is concentrated and mixed with potassium hydroxide liquor at 130℃. The temperature is raised to 155℃ over 20 h to complete the reaction. After being cooled and diluted with water, the melt is run into excess hydrochloric acid and the monopotassium salt is collected by filtration at 30℃ and slurry washed with recycling of the wash liquors. A yield of 87 % is obtained.