Stable formaldehyde-free microcapsules

Patent metadata

Field	Value
Publication number	US-9358189-B2
Application number	US-201214357433-A
Country	US
Kind code	B2
Filing date	Oct 29, 2012
Priority date	Nov 10, 2011
Publication date	Jun 7, 2016
Grant date	Jun 7, 2016

Abstract

The present invention relates to water-dispersible core-shell microcapsules essentially free of formaldehyde. In particular it concerns core-shell microcapsules having a shell obtained by reacting polyisocyanates or polyoxirans cross-linkers and oligomeric compositions which are the reaction products between a polyamine component and a particular mixture of glyoxal and a C 4-6 2,2-dialkoxy-ethanal. The present invention comprises also the invention's core-shell microcapsules as part of a perfuming composition or of a perfuming consumer product.

First claim

What is claimed is:

1. A process for the preparation of a core-shell microcapsule, said process comprising the steps of:
1) preparing an oligomeric composition comprising the reaction product of, or obtainable by reacting together:
a) a polyamine component in the form of melamine or of a mixture of melamine and at least one C 1-4 compound comprising two NH 2 functional groups;
b) an aldehyde component in the form of a mixture of glyoxal, a C 4-6 2,2-dialkoxy-ethanal and optionally a glyoxalate, said mixture having a molar ratio glyoxal/C 4-6 2,2-dialkoxy-ethanal comprised between 1/1 and 10/1; and
c) a protic acid catalyst;

2) preparing an oil-in-water dispersion, wherein the droplet size is comprised between 1 and 600 μm, and comprising:
i) an oil;
ii) a water medium;
iii) at least an oligomeric composition as obtained in step 1);
iv) at least a cross-linker selected amongst:
A) C 4 -C 12 aromatic or aliphatic di- or tri-isocyanates and their biurets, triurets, trimers and trimethylol propane-adduct; and/or
B) a di- or tri-oxiran compounds of formula
A-(oxiran-2-ylmethyl) n
wherein n stands for 2 or 3 and A represents a C 2 -C 6 group optionally comprising from 2 to 6 nitrogen and/or oxygen atoms;

v) optionally a C 1-4 compound comprising two NH 2 functional groups;

3) heating said dispersion;
4) cooling said dispersion; and
5) optionally adding to the dispersion of step 4) at least one cationic polymer and/or urea or ethylene urea; and
6) optionally drying the final dispersion to obtain the dried core-shell microcapsule.

2. A process according to claim 1 , wherein the dispersion comprises:
between 10% and 50% of oil;
between 1% and 20% of oligomeric composition;
between 0.5% and 15% of at least a cross-linker percentage being expressed on a w/w basis relative to the total weight of the dispersion.

3. A process according to claim 1 , wherein the water medium comprises between 0% and 5% of at least a stabilizer and between 0% and 10% of at least a polyol, percentage being expressed on a w/w basis relative to the total weight of the dispersion.

4. A process according to claim 3 , wherein said stabilizer is an ionic surfactant and said polyol is an aliphatic polymeric polyol.

5. A process according to claim 1 , wherein said polyamine component is a mixture of melamine and at least one compound selected amongst urea, 1H-1,2,4-triazole-3,5-diamine and mixtures thereof, and the molar ratio melamine/C 1-4 compound comprising two NH 2 functional groups comprised between 2/1 and 1/3.

6. A process according to claim 1 , wherein said aldehyde component is a mixture of glyoxal and at least one of a glyoxalate, 2,2-dimethoxy-ethanal, 2,2-diethoxy-ethanal and mixtures thereof, and has a molar ratio glyoxal/2,2-dialkoxy-ethanal comprised between 2.2/1 and 6.5/1 and the molar ratio glyoxal/glyoxalate is comprised between 4/1 and 1/1.

7. A process according to claim 1 , wherein there is added an amount of at least one cationic polymer comprised between 0% and 60% percentage being expressed on a w/w basis relative to the total weight of the resin.

8. A process according to claim 1 , wherein said di- or thi-isocyanate is selected amongst hexamethylene diisocyanate, isophorone diisocyanate, xylylene diisocyanate, toluene diisocyanate, a trimethylol propane-adduct of toluene diisocyanate, a trimethylol propane-adduct of xylylene diisocyanate, a trimer of hexamethylene diisocyanate, a trimer of isophorone diisocyanate, a trimethylol propane-adduct of hexamethylene diisocyanate or a biuret of hexamethylene diisocyanate.

9. A process according to claim 1 , wherein said di- or tri-oxiran compound is selected amongst 1,3,5-tris(oxiran-2-ylmethyl)-1,3,5-triazinane-2,4,6-trione, 4-(oxiran-2-ylmethoxy)-N,N-bis(oxiran-2-ylmethyl)aniline, 1,3-bis(oxiran-2-ylmethoxy)benzene, 1,2-bis(oxiran-2-ylmethoxy)ethane and 2,2′-(2-ethyl-2-((oxiran-2-ylmethoxy)methyl)propane-1,3-diyl)bis(oxy)bis(methylene)dioxirane.

Assignees

• Berthier Damien
• Leon Géraldine
• Paret Nicolas
• Ouali Lahoussine
• Firmenich & Cie

Inventors

• Berthier Damien
• Leon Géraldine
• Paret Nicolas
• Ouali Lahoussine

Classifications

• A61K8/11 Primary

  Encapsulated compositions · CPC title

• A61L9/012

  characterised by being in a special form, e.g. gels, emulsions {(A61L9/048 takes precedence)} · CPC title

• A61Q13/00

  Formulations or additives for perfume preparations (essential oils or perfumes per se C11B9/00) · CPC title

• A61K8/062

  Oil-in-water emulsions · CPC title

• A61K8/84

  obtained by reactions otherwise than those involving only carbon-carbon unsaturated bonds · CPC title