Articles of manufacture releasing an active ingredient
The present invention relates to articles of manufacture having a formulation distributed therein, wherein the formulation comprises an active agent which manifests a desirable property when released from the articles of manufacture. The present invention also relates to methods for manufacturing these articles of manufacture, to vehicles for applying the formulation to these articles of manufacture, and to perception indicators indicating the presence and the amount of formulation comprising an active agent applied to an article of manufacture.
1. A method for obtaining a formulation of hydrophobic topical application microparticles having an active ingredient dispersed therein, wherein the formulation is suitable for application to a living subject; said method comprising:
a) forming a formulation comprising a stirred melt of the active ingredient and a non-crosslinked hydrophobic carrier material, wherein the non-crosslinked hydrophobic carrier material is a lipid, a fatty acid-based lipid, a phospholipid, a wax, a fatty acid, a glyceride, a sterol, or any combination thereof; and
b) homogenizing the formulation of a) and obtaining microparticles from the homogenized formulation of a), wherein the microparticles have a body, the body comprising a central part and a surface, the central part and the surface including the non-crosslinked hydrophobic carrier material throughout which is uniformly dispersed the active ingredient;
wherein the microparticles are responsive to one or more of temperature and pH of the living subject to trigger progressive erosion of the surface and the subsequent progressive erosion of the central part to release the non-crosslinked hydrophobic carrier material and the active ingredient, and wherein the microparticles have all three dimensions in the range of about 0.1 micrometers to about 200 micrometers.
2. A method as defined in claim 1 , wherein the microparticles have a release index of between about 1 and about 20.
3. A method as defined in claim 1 , wherein step b) comprises homogenization to obtain microdroplets.
4. A method as defined in claim 3 , further comprising cooling the microdroplets to obtain microparticles.
5. A method as defined in claim 1 , wherein the non-crosslinked hydrophobic carrier material is caproic acid, caprylic acid, capric acid, undecanoic acid, lauric acid, tridecanoic acid, myristic acid, pentadecanoic acid, palmitic acid, heptadecanoic acid, stearic acid, oleic acid, elaidic acid, linoleic acid, linolenic acid, arachidic acid, arachidonic acid, a fatty acid derivative, tripalmitin, tristearin or glycerol monostearate or any combination thereof.
6. A method as defined in claim 1 , wherein the non-crosslinked hydrophobic carrier material includes a composition of stearic acid and palmitic acid.
7. A method as defined in claim 1 , wherein the non-crosslinked hydrophobic carrier material includes a composition of stearic acid, palmitic acid and a natural butter.
8. A method as defined in claim 7 , wherein the natural butter is olive butter, mango butter, grape seed butter, shea butter or lemon butter or any combination thereof.
9. A method as defined in claim 1 , wherein the formulation further comprises a surfactant.
10. A method as defined in claim 9 , wherein the surfactant includes an ionic or a nonionic surfactant.
11. A method as defined in claim 9 , wherein the surfactant includes cetyl trimethylammonium chloride (CTAC).
12. A method as defined in claim 1 , further comprising transferring the microparticles to a substrate that is a textile or a fabric.
13. A method as defined in claim 1 , further comprising adding a perception indicator to the formulation of a).
14. A method as defined in claim 1 , further comprising the step of adding an ancillary agent to the formulation.
15. A method as defined in claim 12 , wherein the microparticles are responsive to body heat established in proximity of the substrate to progressively erode and release the active ingredient.
16. A method as defined in claim 1 , wherein the non-crosslinked hydrophobic carrier material melts at a temperature between about 31° C. and 34° C.