PURPOSE: To uniformly mix major components of powder particles with minor components by supplying the major components continuously first and sending the minor components a little later and mixing and stirring the minor components with the major immediately.

CONSTITUTION: Major components of powder particles and minor components of powder particles like the major components are supplied to a mixing tank 11 and stirred to mix them. In this case, firstly the major components are supplied to the mixing tank 11 continuously and the minor components are supplied a little later to the mixing tank 11 and stirred and mixed with the major components immediately. As a result, the major components and the minor components comprises of powder particles are mixed uniformly and mixing period for each batch can be shortened.