Quality Standard：
| Item | Specification |
| Appearance | White crystalline powder |
| Assay | ≥ 99.5 % |
| Water solubility (100g/L) | Colorless to yellowish transparent liquid |
| Maximum single impurity | ≤ 0.05 |
| Melting point | 111.0~116.0℃ |
| Residue on ignition | ≤ 0.5% |
| Loss on drying | ≤ 1.0% |
| pH (3%W/V) | 3.0-5.5 |
| Arsenic | ≤ 1 ppm |
| Heavy metal | ≤ 5 ppm |
Application: Whitening, sunscreen and anti-aging products
