PROCESS FOR CONTROL OF ELECTRODEPOSITION UTILIZING CATHODIC AND ANODIC FLUSHABLE ELECTRODES

摘要

An electrocoat application assembly is provided for controlling the pH and conductivity of an ionic coating solution. The assembly has a tank for containin g the ionic coating solution with a first and second flushable tubular electrode assem blies located within the tank. The first and second electrode assemblies have an ionic membrane located in spaced relation from an electrode. A similar charge is then placed on the first and second electrodes. Further, the membrane of the first electrode has a charge corresponding to the charge of the electrodes and the ionic membrane of t he second electrode has a charge opposite the charge on the electrodes. The opposit ely charged membrane at the second electrode operates to remove ions having a charge opposite to that of the charge on the electrodes. An electrolyte circulation app aratus is provided for circulating an electrolyte solution through the first and second el ectrodes. Further, a process of controlling an ionic electrodeposition coating system is p rovided for a applying coating solution, which contains a solubilizer and ionic coating part icles, to an object. A first flushable, tubular electrode is placed into the tank that is electrically charged and that is accessible by the solution through a correspondingly charged membrane. A second flushable, tubular electrode is also placed into the tank tha t is electrically charged corresponding to the first electrode and that is accessible by the solution through an oppositely charged membrane. The object to be coated is then supplied with an electrical charge, and the electrodes are supplied with an oppo site electrical charge. The application of electrical current causes a portion of the ionic coating particles to be attracted to and deposited upon the object, and also cau ses a release of excess cations and anions. The ions that have a charge corresponding to the charge of the object are removed at the first electrode by allowing the ions to pass through its charged membrane. Further, the ions that have a charge opposite to t he charge of the object are surprisingly attracted to the like-charged second elect rode and are removed at the second electrode by allowing the ions to pass through its cha rged membrane. The excess cations and anions are then removed from the system by circulating an electrolyte solution through the flushable electrodes.