Azodye Testing
Azodye Testing

Azodye almost exists in all colours as one of the most widely-used synthetic dyestuffs in printing technique (for textiles). It is used for dyeing and printing of natural and synthetic fibres, also for the colouring of paints, plastics and rubber.

When textiles, garments and leather articles come into direct contact with the skin, some azodyes will decompose into arylamines having carcinogenic properties (i.e. carcinogenic azodyes) when they blend with metabolite (perspiration) of human body. However, it presents great hazard if carcinogenic azodyes are absorbed by human bodies. For the purpose of clarity, there are as many as 3,000 azodyes in use and most of them are safe. Only about 200 azodyes are forbidden as they can be reduced to release arylamines having carcinogenic properties.

Regulations

Arylamines having carcinogenic properties

SN

Substance

CAS NO

1

4-aminobiphenyl

92-67-1

2

benzidine

92-87-5

3

4-chloro-o-toluidine

95-69-2

4

2-naphthylamine

91-59-8

5

o-aminoazotoluene

97-56-3

6

5-nitro-o-toluidine

99-55-8

7

p-chloroaniline

106-47-8

8

2,4-diaminoanisole

615-05-4

9

4,4′-diaminobiphenymethane

101-77-9

10

3,3′-dichlorobenzidine

91-94-1

11

3,3′-dimethoxybenzidine

119-90-4

12

3,3′-dimethylbenzidine

119-93-7

13

3,3′-dimethy1-4,4′-diaminobiphenylmthane

838-88-0

14

p-cresidine

120-71-8

15

4,4′-methylene-bis-(2-chloroaniline)

101-14-4

16