Insulation for piezoceramic multilayer actuators

A method for the manufacture of a piezoelectrical multilayer actuator comprising applying thin coats of a piezoceramic material as green leaves, to at least one internal electrode such that the green leaves are stacked one on the other in a block and the internal electrodes are brought alternately to opposite faces of the actuator where they are connected together by an external electrode to form an actuator green body;

• sintering the actuator green body;
• abrasively shaping the sintered green body;
• applying ground metallization for the external electrode;
• applying an area of said actuator to be insulated by thick-layer method a paste comprising an inorganic, low-sintering material or material mixture and an organic binder system, and subjecting the body coated with said paste to a firing process wherein the layer thickness after sintering is between 1 and 40 μm, preferably between 2 and 20 μm or between 4 and 15 μm, wherein the application of the insulating layer takes place after the polarization of the actuator and, by drying at 20–260° C. a covering of all electrodes of one polarity is formed, but no covering of the electrodes of the other polarity and thus a continuous coating is not formed.