Registration Dossier

Physical & Chemical properties

Endpoint summary

Administrative data

Description of key information

Direct Black 168 is a orange powder at 20 °C and 1013 hPa. No melting/boiling reactions were recorded up to 300 °C; vapour pressure can be considered as negligible.

The test item is very water soluble (i.e. 194 g/l) and the partition coefficient log Pow was determined to be lower than -4.

Based on the available information, the substance resulted to be non auto-flammable/flammable/explosive/oxidising agent.

Additional information

APPEARANCE AND PHYSICOCHEMICAL STATE

Direct Black 168 is a black organic powder at 20 °C and 1013 hPa. It is characterized particles having a diameter between 128 and 1.5 μm; in detail, particles with a diameter below 4 μm are ca 2 %. No melting/boiling reactions were recorded up to 300 °C, using the capillary method in liquid bath.

Based on physicochemical properties, the vapour pressure is expected to be negligible.

 

SOLUBILITY AND PARTITION COEFFICIENT

The partition coefficient was first evaluated by using the shake flask method, according to the OECD Guideline 107. The value of LogPow obtained shows that the expected Pow lies outside the range of flask shaking method and it was suggested that it should be estimated by the calculation method. The calculation was performed by the fragment method and the Log Pow was calculated as the sum of its corresponding fragment values (fi), multiplied by the frequency of their occurence (ai), plus the sum of correction terms for intramolecular interactions. The value calculated was -8.44.

The water solubility was assessed by the shake flask method. The substance resulted to be very soluble in water, i.e. 194 g/l at 20 °C and pH 4.8.

PHYSICAL HAZARDS

The relative self-ignition temperature for Direct Black 168 is 195 °C.

The substance does not ignite and not propagate combustion neither by burning with flame or by smouldering along 200 mm of the powder train within the 4 -minute test period.

The substance is incapable of reacting exothermically with combustible materials and it is not thermally or shock sensitive nor is sensitive to friction.

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

Furthermore, the thermal stability and air stability of the substance were investigated using DTA method; the sample shows neither without nor with air any peak between room temperature and 150 °C.