IMPROVEMENTS RELATING TO ENCAPSULATED BENEFIT AGENTS

• US 20160193125A1
• Filed: 07/28/2014
• Published: 07/07/2016
• Est. Priority Date: 07/30/2013
• Status: Active Grant

• Current Assignee: Conopco (Unilever PLC)
• Original Assignee: Conopco (Unilever PLC)
• Inventors: JONES, Craig Warren, LI, Changxi, PAN, Xiaoyun
• Granted Patent: US 10,117,815 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: A23L 27/72 Encapsulation
• CPC Class Codes: A61K 2800/412 Microsized, i.e. having sizes between 0.1 and 100 microns
• CPC Class Codes: A61K 2800/63 More than one coating
• CPC Class Codes: A61K 2800/654 The particulate/core comprising macromolecular material
• CPC Class Codes: A61K 2800/95 Involves in-situ formation or cross-linking of polymers
• CPC Class Codes: A61K 8/11 Encapsulated compositions
• CPC Class Codes: A61K 8/31 Hydrocarbons
• CPC Class Codes: A61K 8/8135 Compositions of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by an acyloxy radical of a saturated carboxylic acid, of carbonic acid or of a haloformic acid; Compositions of derivatives of such polymers, e.g. vinyl esters (polyvinylacetate)
• CPC Class Codes: A61K 8/88 Polyamides
• CPC Class Codes: A61Q 13/00 Formulations or additives for perfume preparations essential oils or perfumes per se C11B9/00
• CPC Class Codes: A61Q 19/10 Washing or bathing preparations
• CPC Class Codes: B01J 13/14 Polymerisation; cross-linking
• CPC Class Codes: B01J 13/22 Coating
• CPC Class Codes: C09B 67/0013 with polymeric coatings
• CPC Class Codes: C09B 67/0097 Dye preparations of special physical nature; Tablets, films, extrusion, microcapsules, sheets, pads, bags with dyes
• CPC Class Codes: C10N 2050/12 Micro capsules
• CPC Class Codes: C11D 17/0039 Coated compositions or coated components in the compositions, (micro)capsules
• CPC Class Codes: C11D 3/505 encapsulated or adsorbed on a carrier, e.g. zeolite or clay
• CPC Class Codes: D06M 23/12 Processes in which the treating agent is incorporated in microcapsules making microcapsules B01J13/02

Abstract

A process for the preparation of a particle, wherein the particle comprises: (a) a core comprising a hydrophobic benefit agent; (b) an outer crosslinked shell, which comprises a crosslinked, hydrophobically modified polyvinyl alcohol, which comprises a crosslinking agent comprising a first dextran aldehyde having a molecular weight of from 2,000 to 2,000,000 Da; and (c) an inner polyamide shell, wherein the shell comprises a polyamide, and wherein the polyamide comprises an aromatic group; wherein the outer crosslinked shell is formed prior to the formation of the inner polyamide shell.

Claims

1. A process for the preparation of a particle, wherein the particle comprises:

(a) a core comprising a hydrophobic benefit agent;

(b) an outer crosslinked shell, which comprises a crosslinked, hydrophobically modified polyvinyl alcohol, which comprises a crosslinking agent comprising a first dextran aldehyde having a molecular weight of from 2,000 to 2,000,000 Da; and

(c) an inner polyamide shell, wherein the shell comprises a polyamide, and wherein the polyamide comprises an aromatic group;

wherein the outer crosslinked shell is formed prior to the formation of the inner polyamide shell.

2. A process as claimed in claim 1, comprising the steps of:

i) forming an emulsion comprising

a) an oil phase comprising the hydrophobic benefit agent and a reactive monomer comprising an aromatic group; and

b) a water phase comprising a hydrophobically modified polyvinyl alcohol;

ii) adding the first dextran aldehyde having a molecular weight of from 2,000 to 2,000,000 Da such that crosslinking of the hydrophobically modified polyvinyl alcohol occurs to form the outer crosslinked shell; and

iii) adding a reactive amine such that the reactive monomer in the oil phase undergoes polymerisation to form the inner polyamide shell.

3. A process as claimed in claim 1, wherein the first dextran aldehyde has a molecular weight of from 2,000 to 50,000 Da, and the outer crosslinked shell further comprises a second dextran aldehyde having a molecular weight of from greater than 50,000, to 2,000,000.

4. A process as claimed in claim 3 wherein the wt/wt ratio of the second dextran aldehyde to the first dextran aldehyde is in the range of from 0.1 to 10.

5. A process as claimed in claim 1, wherein the particle further comprises a deposition aid.

6. A process as claimed in claim 5, wherein the deposition aid is a polysaccharide, more preferably a non-ionic polysaccharide.

7. A process as claimed in claim 1 wherein the particle has an average diameter of from 5 to 50 microns.

8. A process according to claim 1, wherein the benefit agent is a fragrance, an antimicrobial compound or a mixture thereof.

9. The process as claimed in claim 1, wherein the polyamide comprises at least one water miscible monomer and one water immiscible organic monomer.

10. A process as claimed in claim 1, wherein the hydrophobically modified polyvinyl alcohol is modified with butyraldehyde.

11. A process as claimed in claim 10, wherein the core further comprises an additional component selected from a polymeric agent, a solvents and mixtures thereof.

12. A particle obtained from the process of claim 1, wherein the particle comprises:

(a) a core comprising a hydrophobic benefit agent;

(b) an outer crosslinked shell, which comprises a crosslinked, hydrophobically modified polyvinyl alcohol, which comprises a crosslinking agent comprising a first dextran aldehyde having a molecular weight of from 2,000 to 2,000,000 Da; and

(c) an inner polyamide shell, wherein the shell comprises a polyamide, and wherein the polyamide comprises an aromatic group;

wherein the outer crosslinked shell is formed prior to the formation of the inner polyamide shell.

13. A liquid composition comprising the particle as claimed in claim 12, which further comprises:

—

a) at least one surfactant selected from anionic, cationic, non-ionic and zwitterionic surfactants; and

b) solvent, preferably water.

14. A home care or personal care composition comprising at least one particle according to claim 12, the composition preferably being a laundry detergent, laundry conditioner, deodorant, antiperspirant, shampoo, hair conditioner or skin care or skin cleansing product.

15. A method of treatment of a substrate, preferably wherein the substrate is selected from skin, hair and/or textile material, which includes the step of treating the substrate with a composition comprising particles according to claim 12.