Patent ID: 8088215

Claim:
A diffusion reaction method comprising: joining a plurality of reaction liquids relating to a reaction to form a multilayer flow; sandwiching from both sides of the multilayer flow in the depthwise direction using sandwiching liquid so that the multilayer flow is contracted and thinned; and flowing the multilayer flow through a reaction channel to cause a diffusive mixing between laminar flows so as to cause the reaction, wherein: the plurality of reaction liquids are a solution prepared by dissolving fine particle forming materials into a good solvent and a poor solvent with respect to the fine particle forming materials, and the diffusion reaction method further comprises: precipitating fine particles by causing diffusive mixing of the two reaction liquids in the reaction channel and by making them to react each other, and aggregating the precipitated fine particles in the reaction channel by inclusion of a flocculent into the poor solvent.