| content [CD--3] % | 99.0-102.0 |
| appearance | white to pink crystal |
| 5%water solution appearance | colorless |
| volatile matter % | ≤0.1 |
| PH range | 1.38-1.78 |
| CD/H acid | 1.500±0.010 |
| ash content % | ≤0.1 |
| heavy metal % | ≤0.001 |
| Acidic aqueous solution | qualified |
| Alkaline aqueous solution | qualified |
| Photographic properties | qualified |
| aging characteristic | qualified |



