| 摘要 |
1344099 Microcapsules FUJI PHOTO FILM CO Ltd 28 April 1971 [28 April 1970] 11954/71 Heading B8C Microcapsules having a core compound of an oil are prepared by coacervation of two hydrophilic colloids of opposite charge from an aqueous dispersion thereof in an aqueous medium in which the oil is dispersed in the presence of a polyacrylic acid which is added to the system at any time before hardening. Suitable colloids are gelatine and gum arabic. Others include casein, alginate, carrageenan, styrene/maleic anhydride copolymer and polyethylene maleic anhydride copolymer. Emulsifying and shock preventing materials may also be present in the dispersion. Suitable polyacrylic acids are those of the formula where R 1 , R 2 and R 3 may be H or C 1-4 alkyl, X is H, NH 4 or an alkali metal atom and n is an integer from 50-5000. |
