| 摘要 |
PROBLEM TO BE SOLVED: To easily obtain an aqueous dispersion of microcapsules having small particle diameter (distribution) and dense outer shell in high workability in a short time by emulsifying and dispersing a hydrophobic oily liquid with a specific emulsifying and dispersing agent and forming an outer shell composed of a specific resin on the circumference of the dispersed droplet. SOLUTION: The objective microcapsule can be produced by emulsifying and dispersing (A) a hydrophobic oily liquid (e.g. natural mineral oil, animal oil, vegetable oil or synthetic oil optionally mixed with pharmaceuticals, agrochemicals, perfumes, color-developing actents, etc.) in (B) an aqueous medium containing a modified polyvinyl alcohol having an ethylene unit content of 1-24mol% as the emulsifying and dispersing agent and forming an outer shell around the dispersed particle of the component A by the polycondensation of (C) an amino compound (e.g. urea, an alkylmethylol-melamine or guanidine) and (D) an aldehyde (e.g. formaldehyde or glyoxal). The microcapsule is suitable for pressure-sensitive copying paper, printing ink, etc. |
