DSD acid (4,4′-Diaminostilbene-2,2′diasulfonic acid) is used in the production of fluorescent brightener, direct frozen yellow G and direct yellow R, and as insecticide
Light yellow paste or powder, soluble in ethanol and ether, insoluble in water, easy to dissolve in alkali solution. It is easy to oxidize to red, and it has the properties of aromatic acids and amines
DSD acid Specificaiton:
| Appearance | Light yellow powder |
| Purity(%) | ≥95.0 |
| Chromaticity | 0.12% Max |
Alkali insoluble matter | 0.08% Max |
Ash | 2.2% Max |
| Benzyl compounds | 0.25% Max |
