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CAS 16470-24-9 is an organic yellow powder at 20 °C and 1013 hPa; it is a member of the Stilbene Fluorescent Whitening Agent (SFWA) category, group 3, dihydroxyethylamino derivative, tetrasulphonated sodium salt.

The substance has no melting point in the temperature range of 25 – 400 °C at atmospheric pressure (1013 hPa) it changes the colour (decomposes) starting from approximately 360 °C (capillary method).

Particle size distribution showed that the substance is characterized by a MMD of 92.8 µm.

The experimentally partition coefficient value resulted outside the validity domain of the shake flask method (log Kow < -3.9, at 25 °C and pH 7); nevertheless this result can be considered an evidence of the greater affinity of the substance with the water phase, respect to the octanol one and the partition coefficient calculated confirms this conclusion (log Kow: -11.8).

The partition-coefficient (n-octanol / water) has also been determined by an appropriate in silico estimation method because Stilbene Fluorescent Whitening Agents. The estimated value is log Kow: -8.14.

It is very soluble in water (650 g/l at 20 °C and pH ca 9.3), and fat solubility is lower than 0.1 mg/100 g fat.

Under environmental conditions the substance dissociates completely in water.

Based on physicochemical properties above mentioned, vapour pressure, surface tension, flash point can be considered as negligible and disregarded, while viscosity determination is technically not feasible.

It does not ignite and propagate combustion; no chemical groups associated with explosive and oxidising properties are present in the molecule.

It does not meet the criteria to be considered as flammable/explosive/oxidising.

Furthermore, screening test for thermal stability and stability in air, DTA, showed that no decomposition or chemical transformation were found below 150 °C, therefore it is not considered a self-reactive substance.