Patent ID: 7472976

Claim:
A method of controlling a functional liquid supply apparatus, the apparatus having a plurality of functional liquid tanks each storing therein a functional liquid different in kind from one another, the functional liquid tanks being respectively pressurized by a plurality of corresponding pressurizing pumps so as to supply each kind of the functional liquid under pressure from the respective functional liquid tanks to the functional liquid droplet ejection head which ejects the functional liquid droplets, the method comprising: a pressure-loss computing step for computing a pressure loss of each kind of the functional liquid flowing through respective functional liquid passages which extend from the respective functional liquid tanks to the functional liquid droplet ejection head; a supply-pressure computing step for computing a supply pressure of each kind of the functional liquid with the pressure loss taken into consideration so that an in-head pressure of each kind of the functional liquid in the functional liquid droplet ejection head becomes a set pressure which is respectively set in advance; and an independent-pressurizing step for independently pressurizing the plurality of the functional liquid tanks based on the computed supply pressure, wherein the pressure-loss computing step further comprises: a viscosity-data inputting step for inputting viscosity data of the various kinds of functional liquids; and a pressure-loss setting step for setting the pressure loss based on the inputted viscosity data and pressure-loss setting information in which the viscosity data and the pressure loss are correlated with each other.