The amount of chemical liquids dispensed by a chemical liquid supply apparatus is stabilized and dispensing accuracy is remarkably improved. A pump discharges a liquid accommodated in a liquid tank. A filter is connected to the pump through a pump outlet flow path to which a pump discharge-side valve...http://www.google.com.hk/patents/US7594801?utm_source=gb-gplus-share專利 US7594801 - Chemical liquid apparatus and deaerating method
