Chemical Properties
Bright yellow light red. Excellent resistance to solvents such as ethanol, xylene and nitrocellulose. Thermal stability is 140°C. Acid and alkali resistance is poor, and there is migration phenomenon.
Uses
Calcium disodium bis[2-chloro-5-[(2-hydroxy-1-naphthyl)azo]-4-sulphonatobenzoate] is mainly used for printing ink, can also be used for the coloring of plastics.
Synthesis
Calcium disodium bis[2-chloro-5-[(2-hydroxy-1-naphthyl)azo]-4-sulphonatobenzoate] is prepared by diazotization of 2-chloro-5-amino-4-sulfobenzoic acid, coupling with β-naphthol, and precipitation of calcium salts.
![calcium disodium bis[2-chloro-5-[(2-hydroxy-1-naphthyl)azo]-4-sulphonatobenzoate] Structure](https://www.chemicalbook.com/CAS/GIF/5850-80-6.gif)