Abstract
The Procion Black HGS procedure, originally developed for the differentiation of the skin-core effect in viscose rayons, is found to give a characteristic staining on the cross-sections of 6-nylon filaments subjected to the irradiation in Fade-o-meter. As a result of comparative studies with several other microscopical staining methods, it is indicated that the photodegradation of 6-nylon filaments proceeds in a highly heterogeneous manner and is essentially an oxidative reaction due to photoactivated oxygen, giving rise to the formation and accumulation of certain aldehydic substances as relatively stable intermediates.
By means of electron microscope a marked microfibrillar structure is revealed of 6-nylon filaments having undergone a long period irradiation in Fade-o-meter. The photo-oxidative degradation must attack preferentially against the interfibrillar regions, thus unmasking the inherent fiber structure of nylon filaments.
