PROCEDE D'ENCAPSULATION DE SUBSTANCES FINEMENT DISPERSEES DANS UN

摘要

1301052 Microcapsules CIBA GEIGY AG 25 May 1971 [26 May 1970] 17054/71 Heading B8C Solid orliquid particles are microencapsulated by dispersing them in a liquid medium (e.g. water) containing a reactive, surface-active "tenside" which is caused to react to form an insoluble compound which coats the particles. Thereafter, the resulting suspension is mixed with a solution of non-surface-active aminoplast precondensates which are again converted to an insoluble form by condensation polymerization and which coats the particles again to give a product with strengthened walls. The term "tenside" refers to soluble surface active compounds having both hydrophobic and hydrophilic groups, in particular aminoplasts of the urea-formaldehyde and melamineformaldehyde types. The aminoplast precondensate used subsequently may be of the same general type but with low surface activity. Examples refer chiefly to the microencapsulation of dyestuffs and adhesives.