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Irradiation of aqueous solutions of biacetyl (2, 3–butanedione), oxygen and a variety of different azo dyes with light has been shown to result in the rapid oxidation of the dye to phenolic and quinonoid products. The quantum efficiency values of the dyes and the oxygen consumption during fading of some commercially available and some laboratory–synthesised azo dyes have been measured. The photo–oxidation was found to be inhibited by phenolic compounds. Since these compounds are products of the photo–oxidation of azo dyes, they could play an important role in the determination of the dyes' light fastness properties. As keto groups are present in many substrates, the ketone–sensitised photo–oxidation could be relevant in the fading of azo dyes.

A polymer of an isocyanide (R–N=C<)n has been synthesized in which R contains a benzo‐18‐crown‐6 group. The crown ether rings are on top of each other and form channels which bind metal ions. The channel compound can be incorporated in vesicles and is able to transport ions across the bilayer membrane.

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The bathophenanthroline indicator paper was introduced to the field of paper conservation as a contact test to detect the presence of iron(II) ions in objects of cultural value, especially manuscripts containing iron gall ink. Due to their catalytic activity, iron(II) ions are detrimental to paper and other organic substrates. Paper conservators apply different treatments to remove or deactivate iron(II) ions from ink corroded manuscripts, e. g. washing and the phytate treatment. By comparing stability constants of the different complexes, involved with the testing on iron gall ink and the phytate treatment, it is shown that the bathophenanthroline test can safely be applied at nearly neutral pH-values (pH = 6), without the risk of destroying the ink or phytate complex. Therefore, it can be used to check the efficacy of the phytate treatment applied to complex and remove iron(II) ions.Zusammenfassung/résumé at end of article