EP-4192614-B1 - PROCESS FOR THE PREPARATION OF MICROCAPSULES

Inventors

• TECCHIO, Katherine
• RAABE, Britta
• ROST, Benjamin
• KOEPKE, Christina
• GEORGI, Julian, Alexander
• BERTRAM, RALF
• GREGOR, Daniela
• VOGEL, ANDREAS

Dates

Publication Date

20260506

Application Date

20210805

Claims (5)

1. Biodegradable microcapsule comprising or consisting of (a) a core comprising or consisting of at least one hydrophobic active ingredient; (b) a capsule shell comprising or consisting of a crosslinking matrix or crosslinking units of at least one polysaccharide and at least one protein and at least one first crosslinking agent; and optionally at least one first protective colloid; and at least one further crosslinking agent; wherein the at least one first crosslinking agent is a polyisocyanate having two or more isocyanate groups; and wherein the content of the polyisocyanate is 20 wt.-% or less based on the capsule shell; and wherein the further crosslinking agent is selected from the group consisting of transglutaminase, peroxidase, secondary plant substances selected from the group consisting of polyphenols, gallic acid, ferulic acid, hesperidin, cinnamaldehyde, vanillin, carvacrol, and mixtures of two or more of the aforementioned crosslinking agents.
2. Biodegradable microcapsule according to claim 1, wherein the capsule shell comprises or consists of: a crosslinking matrix or crosslinking units from a polymerization and/or crosslinking of at least one protein with the first and the further crosslinking agent; and a crosslinking matrix or crosslinking units from a polymerization and/or crosslinking of at least one polysaccharide with the first and the further crosslinking agent.
3. Microcapsule slurry comprising a microcapsule according to claim 1 or 2, optionally in combination with a thickener and/or a preservative.
4. Use of the microcapsules according to one or more of claims 1 to 2 or a microcapsule slurry according to claim 3, for the preparation of household products, textile care products, detergents, fabric softeners, cleaning agents, scent boosters or fragrance enhancers in liquid or solid form, cosmetics, personal care products, perfume compositions, agricultural products, pharmaceutical products or print coating for paper.
5. Household products, fabric care products, detergents, fabric softeners, cleaning agents, scent boosters and fragrance enhancers, cosmetics, personal care products, perfume compositions, agricultural products, or pharmaceutical products, comprising a microcapsule according to claim 1 or 2 or a microcapsule slurry according to claim 3.

Description

Field of the invention The present invention relates to biodegradable protein- and polysaccharide-based microcapsules as well as dispersions of such microcapsules (microcapsule slurry) that enclose at least one hydrophobic active ingredient, preferably for perfume- or aroma-containing polysaccharide- and protein-based microcapsules, which have a well-balanced biodegradability, stability and performance compared to microcapsules according to the state of the art. In addition, the present disclosure relates to biodegradable microcapsules comprising at least one hydrophobic active agent obtainable by the process described herein. In another aspect, the present invention relates to the use of the microcapsules and dispersions as an ingredient in household products, textile care products, laundry detergents, fabric softeners, cleaning agents, scent boosters or fragrance enhancers in liquid or solid form, cosmetics, personal care products, perfume compositions, agricultural products, pharmaceutical products or print coating for paper. Finally, the present invention relates to consumer products comprising such microcapsules or microcapsule dispersions. Microcapsules are particles comprising a core and a wall material surrounding the core, wherein the core may be a solid, liquid or gaseous substance surrounded by a polymeric dense, permeable or semi-permeable wall material. During manufacture, the polymers of the starting ingredients precipitate onto the substances to be encapsulated after emulsification and coacervation or interfacial polymerization. The core is also referred to as the inner phase. Other names used for the wall include outer phase, shell or coating. The diameter of the microcapsules typically varies in the range of 1 to 1 000 µm. The wall thickness is typically 0.5 to 150 µm but can be varied in the range of 5 · 10-9 m to 5 · 10-6 m. Typically loadings of 25 to 95 wt.-%, but also those of 1 to 99 wt.-% are possible. Encapsulation of an active ingredient with a suitable wall material (coating material) can be done for several reasons: Conversion of liquids into a manageable powder form (e.g., coating of vegetable oils, fats);Time-controlled release of substances (dosage control, depot effect for pharmaceuticals, pesticides and fertilizers);Taste, odor and color lamination (e.g., bitter or pungent aroma substances);Protection against light, oxidation, heat, acids or bases (e.g., vitamins, aroma substances, etc.)Moisture protection (e.g., hygroscopic salts or minerals);Retardation of losses of volatile components (e.g., aroma substances);Prevention of premature chemical reactions with other mixture components;Better handling before or during processing (flow properties, dust formation);Protection of personnel from harmful or unpleasant materials (chemicals, aroma concentrates); or improved solubility/suspendability due to surface modification. Hydrophobic active ingredients, such as fragrances or aroma substances, can be easily incorporated into numerous and diverse application formulations through encapsulation. The contents of microcapsules can be released in a variety of ways and, in particular, is based on one of the mechanisms described below: The capsules are mechanically disrupted by crushing or shearing. This mechanism is used, for example, in reaction carbonless paper.The capsules are destroyed by melting the wall material. Based on this mechanism, ingredients such as raising agents or flavors are released, for example, in baking mixtures only during the baking process.The capsules are destroyed by dissolving the wall material. This mechanism is used, for example, in washing powder so that encapsulated ingredients such as enzymes are only released during the washing process.The capsules remain intact, and the capsule contents are gradually released by diffusion through the capsule wall. Based on this mechanism, e.g., a slow and uniform release of drug ingredients in the body can be achieved. Based on their properties, microcapsules are used in the printing industry, food industry (vitamins, flavors, plant extracts, enzymes, microorganisms), agricultural chemistry (fertilizers, pesticides), feed industry (minerals, vitamins, enzymes, drugs, microorganisms), pharmaceutical industry, detergent industry, and cosmetic industry, among others. Many articles of daily use, such as cleaning agents, fabric softeners, washing powders, liquid detergents, shower gels, shampoos, deodorants, body lotions, etc., are nowadays perfumed with fragrant substances or mixtures of fragrant substances. Very often, the fragrant substances interact with other components of the formulation, or the more volatile components of a perfumed product evaporate prematurely. This usually results in the fragrance impression of the perfumery changing over time or even disappearing completely. Microencapsulation of such fragrance mixtures offers the possibility of reducing or completely preventing interactions in the perfumed produ