1-(4-methyl-2-nitrophenylazo)-2-naphthol

Stability in organic solvents and identity of relevant degradation products

Link to relevant study record(s)

Reference

Endpoint:

stability in organic solvents and identity of relevant degradation products

Type of information:

experimental study

Adequacy of study:

key study

Study period:

10.December 2007

Reliability:

2 (reliable with restrictions)

Guideline:

other: Method agreed upon at the "Analytical Experts Meeting" of ETAD (Basel) on January 12, 2005

Principles of method if other than guideline:

The substance was suspended in water saturated octanol and shaken for 2 hours at 30 °C (+/-2°C). Then shaking was continued at ambient temperature for 70 hours followed by filtration. Quantification of the test substance was done by UV-vis spectrometry by applying the Lambert-Beer rule.

GLP compliance:

no

Specific details on test material used for the study:

The purity of the test material was >99,5%.
About 5 mg of the test sample were suspended in 30 ml water saturated octanol in a sample flask and were shaken for 2 hours at 30°C (+/- 2°C) on a "Büchi Syncore Polyvap" with 400 rpm. The shaking was continued at ambient temperature (22 - 23°C, determined) for 70 hours, followed by filtration through a 0.2µm membrane filter and then through two 0.2 µm membrane filters. A residue of undissolved colorant remained on the filter. No particles were noticed in the clear solution by visually check.

Test substance stable:

yes

Transformation products:

not measured

Conclusions:

Test substance is stable in organic solvents but has a low solubility

Executive summary:

The solubility of Pigment Red 3 in water saturated octanol at 22-23°C was determined to be 19.8 mg/l.The test substance is stable in organic solvents.

Description of key information

Pigment Red 3 is stable in organic solvents.