Abstract
First the article of E. G. E. Hawkins (1956) on the degradation of novolak resins is introduced. His experiment involved the following complicated steps : bromination, methylation of the phenolic groups, oxydation to oxybenzophenones, cleavage of the benzophenones to bromoacids and bromoanisoles, demethylation and decarboxylation. For the cleavage of benzophenones was applied Swan (1948) reaction, using kalium-butoxide as catalyst. Next the historical relations between dioxydiphenylmethanes, dioxybenzophenones, xanthenes and xanthones, which being closely related to the degradation of phenolic resins, are discussed referring to the literatures : J. H. Gladstone-A. Tribe, R. Richter (1882), C. Graebe (1889), W. Stadel (1894), M. R. Fosse (1903), F. Zmerzlikar (1910), L. H. Bender (1953), Hawkins et al (1957) etc.
