| abstract |
The present invention relates to an improved controlled delivery system that can be incorporated in soap bars to enhance deposition of active ingredients and sensory markers onto skin. The carrier system also provides controlled release or prolonged release of these actives from the skin over an extended period of time. The controlled delivery system of the present invention comprises substantially free-flowing, powder formed of solid hydrophobic, positively charged, nanospheres of encapsulated active ingredients, that are encapsulated in moisture sensitive microspheres. The high cationic charge density of the nanosphere improves deposition of active ingredients onto skin. The high cationic charge density on the nanosphere surface is created by incorporating a cationic conditioning agent into the solid hydrophobic matrix of the nanospheres, by incorporating a cationic charge “booster” in the moisture sensitive microsphere matrix, or by using a cationic conditioning agent in the nanosphere matrix in conjunction with a cationic charge “booster” in the microsphere matrix. The invention also pertains to soap products comprising the controlled release system of the present invention. |