169 220
contributi
Modifiche
Creata pagina con "However, galalith was not very successful and was quickly abandoned with the advent of celluloid. Its porosity in fact makes it strongly hygroscopic, with the tendency to..."
However, galalith was not very successful and was quickly abandoned with the advent of [[celluloid]]. Its porosity in fact makes it strongly hygroscopic, with the tendency to expand with humidity, which leads to problems of mechanical stability. Even worse, again for this characteristic, its resistance to ink, which tends to produce permanent stains. In addition, immersion in water (even for just a few hours) involves an expansion (up to 10%) and a softening of the material, with destructive consequences as a subsequent drying it will lose its original shape. Finally, with time the material tends to present cracks (usually they occur for long exposure to light and are believed to be caused by changes in moisture) that are only apparently superficial and can not be removed.