| 摘要 |
PURPOSE:To efficiently remove residual formaldehyde without losing capsule properties by adjusting a capsule dispersion liquid having an aldehyde polycondensation resin wall film to an alkaline side in the presence of an aliphatic aldehyde. CONSTITUTION:To a microcapsule dispersion liquid having an aldehyde polycondensation resin wall film formed by using an acid catalyst, an aliphatic aldehyde such as acetaldehyde or the like is added and a pH of the resultant dispersion liquid to about 9 or more, pref., about 10-12 by using caustic soda or the like and, subsequently, the pH adjusted liquid is warmed. By this method, removal effect of residual aldehyde is enhanced without losing properties of the capsule wall film. |
