Method of detecting plastics articles, and a detector device

2/ A method according to claim 1, in which each article is put into contact with the static electricity generator and with the charge evaluator member in order to determine whether it is a plastics article or a paper article.

3/ A plastics material detector, in particular for a postal sorting installation through which articles pass, the detector being for automatically distinguishing between articles having an outside surface of plastics material and articles having an outside surface of paper, said detector comprising a first conductive surface mounted on a support and electrically connected to a voltage generator constituting a member for generating static electricity, and a second conductive surface also mounted on the support and electrically connected to a processor unit forming a member for evaluating electrostatic charge, said first and second conductive surfaces being separated from each other along said support and being designed to come successively into contact with each article to be tested.

4/ A detector according to claim 3, further comprising a sensor for sensing the passage of articles in order to synchronize the evaluation of electrostatic charge on each article with its passage along said second conductive surface.

5/ A detector according to claim 3, further comprising an antistatic brush of carbon fibers for electrostatically discharging each article after its electrostatic charge has been evaluated.

6/ A detector according to claim 3, in which said support is made of electrically insulating material and that is substantially ski-shaped, said articles being moved along said support in order to be tested.

7/ A detector according to claim 6, in which said support is made of molded ceramic material.

8/ A postal sorting installation including an electrostatic detector according to claim 3.