| 摘要 |
<p>In a process for the production of microcapsules by coacervation of gelatin, carboxymethyl cellulose (CMC) and a second anionic polymer such as a polyvinylmethylether/maleic anhydride copolymer or an ethylene/maleic anhydride/copolymer, the weight ratio of gelatin:CMC is chosen to be in the range 1:0.14 to 1:0.05, and the CMC used is chosen to have a viscosity in the range of from 50 to 140 mPas (cps), when measured in 6.0% by weight aqueous solution at 20 DEG C using a Brookfield RVT viscometer, Spindle No. 1, 10 r.p.m. The use of the specified weight ratio and CMC type permits significant increases in the solids content at which encapsulation can be carried out without increasing process viscosities to an unacceptable extent and/or giving rise to poor quality microcapsules. The process is particularly suitable for producing microcapsules for use in pressure-sensitive copying paper.</p> |
