| abstract |
The present invention relates to a method for preparing solid microcapsules (20), comprising the steps of: na) adding under agitation a composition C1 comprising at least one active material to a cross-linkable liquid composition C2, nwherein the active material is not an additive to be used in the lubricant, fuel or bitumen industries, or in drilling sludges or muds, or an additive to be used in oil exploration/production, ncomposition C1 and composition C2 being immiscible with each other, nso that a first emulsion is obtained, said first emulsion comprising droplets (1) of composition C1 dispersed in composition C2, nb) adding under agitation the first emulsion obtained in step a) to a liquid composition C3, ncomposition C3 and composition C2 being immiscible with each other, nso that a second emulsion is obtained, said second emulsion comprising droplets (5) dispersed in composition C3, nc) loading the second emulsion obtained in step b) in a mixer which applies a homogeneous controlled shear rate to said second emulsion, said shear rate being from 1 000 s -1 to 100 000 s -1 , nso that a third emulsion is obtained, said third emulsion comprising droplets (10) dispersed in composition C3, and nd) cross-linking the droplets (10) obtained in step c), nso that solid microcapsules (20) dispersed in composition C3 are obtained. |