The method of detecting plastics material, in particular for a postal sorting
installation through which articles pass, is intended to distinguish automatically
between articles having an outside surface made of plastics material and articles
having an outside surface made of paper. The method consists in moving each article
past an electrostatic generator, and then past a member for evaluating electrostatic
charge so as to compare the charge on the article with a reference value in order
to detect whether the article is a plastics article or a paper article. The method
increases the reliability of detection.
