Stand der Forschung an der photographischen Gelatine

Abstract

It was the aim of the present work to characterize the gelatin by molecular parameters and investigate the elastically active elements of gelatin gels.
The molecular characterization of the gelatin was established by gel permeation chromatography, gel electrophoresis and the measurement of light scattering.
The structural elements of the gelatin gel were made visible by two independent methods of preparation: negative staining and freeze etching. The resulting samples were investigated with the transmission electron microscope. The fibrous-association-type structure of the gelatin gel was further more quantitatively described by the measurement of permeation of water through the gel network.
The process of gelation was followed with the oscillating cup viscosimeter. This method proved to be especially sensitive for the detection of the first elastic network.
It could be shown that only a distinct part of the gelatin is converted into elastically active elements. Some crude correlations were found between the thickness and the number of elastically active fibrills on the one hand and the parameters of gelation e.g., setting temperature, gelatin concentration and the duration of conditioning on the other hand.