Patent ID: 7488513

Claim:
A method of producing microcapsules having an electrophoretic particle dispersion encapsulated comprising: emulsifying and dispersing in a hydrophilic medium a hydrophobic dispersion having electrophoretic particles dispersed in a hydrophobic medium by using a first stirring apparatus transferring said hydrophobic dispersion emulsified and dispersed in the hydrophilic medium to a second stirring apparatus; and forming microcapsules of the said hydrophobic dispersion emulsified and dispersed in the hydrophilic medium under stirring with a stirring blade of said second stirring apparatus, wherein in said first stirring apparatus, a circumferential speed at the end of a stirring part is 2 m/s to 90 m/s, and a distance (a) between the end of the stirring part and that immobile part of the stirring apparatus which is nearest to the end of the stirring part is 0 mm<(a)<20 mm, in said second stirring apparatus a circumferential speed of the stirring blade is 0.2 m/s to 5.0 m/s, and the second stirring apparatus is accommodated in a reaction container so as to enable stirring of the stirring blade used in forming microcapsules of the emulsified and dispersed hydrophobic dispersion, a ratio (d 1 /d 2 ) of a blade diameter (d 1 ) of the stirring blade to a inner diameter (d 2 ) of the reaction container is 0.4 to 0.9, and a ratio (d 1 /h 1 ) of the blade diameter (d 1 ) to the total height (h 1 ) of the stirring blade is 0.3 to 1.5.