Patent DE-102009026863-A1 (DE)
Title: Device for applying a fluid or pasty medium on a material web such as paper or card board, comprises an application device, which transfers the medium on a coating position on the material web
Inventor: MENDEZ-GALLON BENJAMIN
IPC: B05C9/08
Filed: 2009-06-09
Abstract: The device for applying a fluid or pasty medium on a material web (M) such as paper or card board, comprises an application device (1, 3), which transfers the medium on a coating position on the material web. The application device and/or a counter support forming a material web-coating gap with the application device is equipped in the area of a coating position with a device producing an electrostatic power in order to electrostatically divert droplet of the medium emerging at the coating position. The device for applying a fluid or pasty medium on a material web (M) such as paper or card board, comprises an application device (1, 3), which transfers the medium on a coating position on the material web. The application device and/or a counter support forming a material web-coating gap with the application device is equipped in the area of a coating position with a device producing an electrostatic power in order to electrostatically divert droplet of the medium emerging at the coating position. The application device or the counter support is equipped with the device producing electrostatic power. The application device and the counter support are arranged with the electrostatic power producing device. The counter support is formed as application device in order to coat the material web on both sides with homogeneous or different fluid or pasty medium. The application device and the counter support are equipped respectively with an electrostatic power producing devices that are rumbled on its side to the material web. The application device and/or the counter support are implemented as roller and/or rollers. The electrostatic power producing device has piezoelectric characteristics and has a piezoelectric layer that produces the electrostatic power through the application pressure producing on the application position. The piezoelectric layer is piezoelectric lacquer, piezoelectric film, piezoelectric microfiber embedded in a polymer matrix, piezoelectric granulate, piezoelectric roller covering material, foaming or pasty piezoelectric covering material and/or piezoelectric fiber. The electrostatic power producing device is activated through corona discharge and has a condenser having an electrical conductive layer. The condenser produces an electric field in the area of the coating position and/or the coating gap during applying direct current voltage. The application device and/or the counter support comprises dielectric coating, electrical conductive layer, dielectric and/or two electric conductive layers. The electrical conductive layers form a roller core in the case of a roller-shaped formation of the application device and/or counter support. The application device and/or the counter support comprises dielectric coating and/or electrical conductive layers in contact with the coating medium. The electrical conductive layer is a metal layer, where segmented layer is segmented in its circumferential direction in the case of a roller-shaped formation of the application device and/or the counter support. The electrostatic power producing device and the electrical conductive layer have electrically insulated wires that are electrically loaded in the area of the coating position. The wires are arranged in its circumferential direction in interval that extends parallel to the roller axis, in the formation of the application device and/or the counter support. The device for producing the electrostatic power in the direction to external surface of the application device, and/or the counter support have electrically loaded recess in the area of the coating position. An independent claim is included for a method for applying a fluid or pasty medium on a material web.