Method and apparatus for preparation and deaeration of coating liquid

An apparatus for preparation and deaeration of a coating liquid, the apparatus comprising:

• constituent liquid tanks which hold a plurality of coating liquid constituent liquids for preparation of a coating liquid;
• a preparation and deaeration device which stirs and mixes the coating liquid constituent liquids fed into a stirring tank from the constituent liquid tanks at such a low speed that bubbles are not formed to prepare the coating liquid, and removes bubbles in the liquid under reduced pressure;
• an ultrasonic floatation type deaeration devices which applies an ultrasonic wave to the coating liquid prepared and deaerated in the preparation and deaeration device in a floatation tank under one of atmospheric pressure and reduced pressure so as to remove bubbles in the coating liquid;
• and
• a pipeline type continuous deaeration device which continuously feeds the coating liquid deaerated in the ultrasonic floatation type deaeration device through a pipeline in such a manner that no liquid surface is created, and simultaneously applies an ultrasonic wave to the coating liquid under pressure to dissolve bubbles in the coating liquid so as to remove the bubbles in the coating liquid.