IMPERMEABLE CAPSULES Russian patent published in 2012 - IPC A61K8/11 A61Q11/00 

FIELD: medicine.

SUBSTANCE: invention refers to medicine, and describes a capsule used in oral care and personal hygiene compositions, containing a nucleus and a coating enveloping and enclosing the nucleus with the coating containing at least one first polymer characterised by the first parameter of water solubility, and at least one second polymer characterised by the parameter of water solubility greater than the first parameter of water solubility, and the capsule represents a microcapsule wherein the parameter of solubility of at least one second polymer is at least 0.5 Hildebrand Unit greater the parameter of solubility of at least one first polymer. If exposed to the water medium, the first polymer starts to swell up, and water starts to flow in the capsule. Besides, the second polymer is taken up by flowing water. Once water is absorbed by the second polymer which is swelled up, the average free volume decreases in the coating, and a crooked path for the materials crossing a wall border increases. Also, there are described a method of reducing water penetration of the coating and a composition containing such capsule.

EFFECT: it results in decreasing the flowing rates through the capsule wall.

11 cl, 1 ex, 1 tbl