Method for producing an aqueous dispersion of pseudopolirrotaxano

A method for producing an aqueous dispersion of pseudopolirrotaxano, the method comprising: a mixing step for dissolving a polyethylene glycol and a cyclodextrin in an aqueous medium to prepare a mixed solution; and a cooling step for cooling continuously or intermittently mixed in a state of flux to precipitate particles pseudopolirrotaxano solution wherein particles psedopolirrotaxano containing polyethylene glycol is included in cavities of cyclodextrin molecules in a skewered manner ; the mixed solution is heated to a temperature of 60 ° C to 90 ° C in the mixing step; temperature rating is 5 ° C to 20 ° C in the cooling step; the cooling step is performed at a cooling rate of 0.01 to 30 ° C / min; and particles in the aqueous dispersion have a size pseudopolirrotaxano volume average particle analyzed using a particle size analyzer by laser diffraction of 1 to 200 .mu.m.