Multilayer composite facilitating sampling of hard core bonded to outer reinforcing surfaces, interposes non-adherent agent locally, between core and reinforcement

摘要

Adhesion is prevented by agents (4) located between core (1) and reinforcing layers (2, 3). External markers (5) assist agent location. This permits core removal and separation, without loss of material. An independent claim is included for methods making the corresponding multilayer object and extracting the sample of the core from it.