Abstract: The process for producing highly concentrated nanometer-size fine particles of an organic pigment, which comprises dissolving the organic pigment in an amide solvent, especially an organic solvent comprising at least 50 vol % 1-methyl-2-pyrrodinone, and pouring the resultant organic pigment solution with stirring into a poor solvent which is not compatible with the organic pigment. The pigment may be a quinacridone pigment, phthalocyanine pigment etc. Any atmospheric pressure to a sub-critical and/or supercritical state can be employed as the production conditions.

Abstract: A flow controller in a flow control valve for an internal combustion engine. When the flow control valve is operated in a closing direction upon the occurrence of an abnormal state in the flow control valve such as sticking, resonance frequency vibration is applied to the valve so that a sliding resistance force of a screw mechanism can be lowered and the valve can be closed. To prevent problems with the flow control valve such as being out-of-control, a setting time is added to a drive period according to the variation in the motor torque. Because the flow control valve can be reliably closed, and an out-of-control condition of the flow control valve can be prevented, an incorrect operation of the engine can be avoided.