Patent ID: 7131555

Claim:
A method for discharging fluid, comprising: feeding fluid from a fluid supply device to a gap formed by two opposing surfaces of two members, while keeping the two members moving relative to each other along a gap direction of the gap; intermittently discharging the fluid by utilizing a pressure change made by changing the gap, and controlling a fluid discharge amount per dot depending on pressure and flow rate characteristics of the fluid supply device; and setting the gap to have a minimum value h 0 such that the intermittent discharging is performed while h 0 >h 1 , wherein: an intermittent discharge amount per dot is generally proportional to the minimum value h 0 when h 0 is set in the range of 0<h 0 <h x , the intermittent discharge amount per dot is generally constant independent of the minimum value h 0 when h 0 >h x , the intermittent discharge amount per dot relative to h 0 is represented by a curved line when h 0 is set in the range of 0<h 0 <h x , and a first straight line is tangent to the curved line at a portion near h 0 =0, the intermittent discharge amount per dot is generally constant and represented by a second straight line when h 0 >h x , and an intersection between the first straight line and the second straight line is defined as h 0 =h x .