Molecular Formula: C₇H₁₁O₉P
Chemical Name: 2-Phosphonobutane-1,2,4-tricarboxylic acid
Appearance:Colorless or faint yellow liquid 
Active acid: ≥50.0％
Specific gravity (20℃)g/cm³≥1.27
Phosphorous acid (PO₄³-): ≤0.3％
H₃PO₃(PO₃³-): ≤0.4％
PH( 1％solution ): ≤2.0