Why we have written a volume about this particular aspect of pharmaceutical technology, and what its usefulness might be, since on this subject there are countless publications and countless articles in specialized magazines that every day add new knowledge?Our purpose is twofold, on the one hand to report our experience in the field and the results obtained with our particular technology, on the other hand to denounce the regrettable use that some companies make of this technology on the commercial and promotional level, with the sole objective of corporate profit.