Abstract
In this paper ten articles of G. Zigeuner and co-workers on “Über die Struktur der kiinstlichem Harze (1954-59)” are abstracted. They obtained a great deal of di-and tri-nuclear novolak-oligomers by oxydative degradation of phenolic resins and intermediate compounds. In 1955 they discovered two trinuclear oligomers which have two different melting points. These were no other than the steric isomers expected by Megson in 1948. Introducing the Megson's paper and Zigeuner's works the present author pointed out that the steric problem of novolak is very interesting but difficult field of the phenolic resin chemistry.
