Process for the preparation of an additive-containing anionic clay comprising the steps of preparing a physical mixture of a divalent and a trivalent metal compound, calcining the physical mixture at a temperature in the range 200-800\xb0 C. Furthermore, if a BD_ADDR of a partner device is already registered, the wireless communication device of the present invention can be link-connected with the partner device without performing authentication of the partner device. , oxygen to form a film on a substrate, such as to provide an adhesion layer between a silicon movable structure in an optical MEMS device and a gold layer serving as a reflecting surface.