Trisodium [3-[[4-[[6-anilino-1-hydroxy-4-sulpho-2-naphthyl]azo]-5-hydroxy-o-tolyl]azo]naphthalene-1,5-disulphonato(5-)]cuprate(3-)

Melting point / freezing point

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

melting point/freezing point

Type of information:

other: read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

weight of evidence

Study period:

2014

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

The complete read across justification is detailed in section 13. Source study has reliability 1.

Qualifier:

according to guideline

Guideline:

OECD Guideline 102 (Melting point / Melting Range)

GLP compliance:

yes

Type of method:

thermal analysis

Remarks:

Differential Scanning Calorimetry

Decomposition:

yes

Decomp. temp.:

> 230 °C

The test item had no melting temperature between -20 °C and begin of decomposition not higher than 230 °C.

Observed thermic processes

A broad endotherme starting at about 100 °C was observed. This can be attributed to vaporization of parts of the test item. The vaporization is confirmed by the TG/DTA-measurement (non-GLP), where a weight loss of 7.3 % was found at 151 °C.

Most likely starting at about 200 °C, where the endothermic signal becomes smaller, but latest at 230 °C, where obviously an exothermic heat flow can be observed, the test item is not stable any more.

After the measurement with a final temperature of 320 °C, a weight loss of 14.9 % could be stated, but the test item did not show any visual change and it was as powdery as before. This is a clear indication, that the test item was not molten up to this temperature. Therefore, the broad endotherme with a maximum temperature of 203 °C cannot be taken as the melting of the test item.

Conclusions:

The test substance decomposes at T > 230°C before melting.

Executive summary:

Method

OECD guideline 102. Thermal analysis by DSC.

Results

Decomposition before melting at T above 230 °C.

Reference 2

Endpoint:

melting point/freezing point

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study without detailed documentation

Qualifier:

according to guideline

Guideline:

EU Method A.1 (Melting / Freezing Temperature)

Principles of method if other than guideline:

No information on the method used during the test is available.

GLP compliance:

yes

Type of method:

other: no available information

Melting / freezing pt.:

> 360 °C

Conclusions:

Melting point > 360 °C.

Executive summary:

Method

The test has been conducted according to EU method A.1. No other information on method is available.

Available information derives from a migrated NONS file, as per Article 25(3) request, and permission to refer is granted by ECHA.

Results

Melting point > 360 °C.

Description of key information

No melting up to T above 300 °C.  

Additional information

No data on test substance itself was available. A weight of evidence approach was adopted, using Similar Substance 01 and 02 as read across substances. In particular, Similar Substance 01 is an isomer of test substance, differing only for the position of one functional group on an aromatic ring; Similar Substance 02 has structural similarity with test susbtance. A detailed justification of the read across process is attached in section 13.

Experimentally, no melting point was found for Similar Substance 01 up to 360 °C, based on migrated information from NONS file, as per Article 25(3) request. Permission to refer is granted by ECHA.

Similarly, Similar Substance 02 does not melt up to 320 °C, but starts to decompose at 230 °C.