Technische und wirtschaftliche Chancen von neuen, ökotoxiko-logisch bewerteten Direktfarbstoffen für die Papierindustrie

There are special regulations and legislation governing the manufacture and application of paper dyes and the use of coloured paper. The debate on these substances focuses primarily on azo dyestuffs, which are a particularly important class of products for the paper industry. Increasingly stringent legislation has led to a number of developments geared to ensuring that even the chemical intermediates used in the production of paper dyes meet current ecotox standards. There are already many products with proven technical properties and there is a sound scientific basis for the development of many others. One potential point of conflict that we see is achieving the economic basis required for successful marketing of products that meet today's ecotox requirements. Under current chemicals legislation, developing and obtaining approval for new products is very expensive. However, the use of suspect chemicals is out of the question, at any rate for traditional suppliers. Azo dyestuffs are produced by diazoti-sation of aromatic amines followed by conversion of the resulting diazonium compounds with coupling components. Reductive splitting of these products, e.g. in the human organism, can generate aromatic amines. Consequently, ecotoxicological evaluation of these products is based on the aromatic amines they could release in reductive conditions. These days, it is generally recognised the sulphonated amines are not carcinogenic. Our paper dyes do not release any of the aromatic amines that are classified as carcinogenic in the 1994 MAK list, even in reductive conditions. This paper aims to heighten awareness of recent developments.