In the production process of aluminium frames, the extruded aluminium bars, after the coating cycle, packed and protected with cellophane, can be stored outside for a short period of time. During this period of outdoor storage, the aluminium profiles can be accidentally drenched by the rain. The water, penetrating between the folds in the cellophane, can get in contact with the coating film and stagnate for a quite long period. If, subsequently, these profiles with water inside the cellophane are exposed to direct sunlight, the temperature will rise quickly and will reach 50/60°C. In these conditions, the coating film may adsorb some water causing a significant colour change, commonly know as “blanching”.
Continue reading the article published in IPCM magazine March/April 2014 to learn more about blanching phenomenon and to discover the ST's innovative solution that solves this problem.