EP3890838A1 - Microcapsules - Google Patents

Abstract

The present invention relates to microcapsules comprising (a) a core, containing at least one active ingredient, and (b) a capsule wall, the capsule wall consisting of at least three polymer layers and at least one of the polymer layers consisting of a first phenol resin, the first phenol resin comprising 3 to 50 wt% of groupings that derive from at least one aromatic polyol, and at least one further of the polymer layers consisting of a second phenol resin, the second phenol resin comprising 3 to 50 wt% groupings that derive from at least one triphenol.

Description

MICROCAPSULES

FIELD OF THE INVENTION

The invention is in the field of microcapsules and their use in cosmetic preparations, pharmaceutical agents, household and cleaning agents and technical compositions, such as e.g. Adhesive and coating compositions, paints, varnishes, binders, materials such as plastics, paper, textiles, lubricants, building materials, dyes, organic and inorganic powders, pigment dispersions, agrochemicals, phase change materials, flame retardants and the manufacture of the capsules.

BACKGROUND OF THE INVENTION

For a variety of applications, from pharmacy to cosmetics, detergents and cleaning agents to fertilizers, the delayed release of active ingredients from a capsule shell has become increasingly important in recent years. In the food sector, too, it is often desirable if, in particular, flavoring substances are not released spontaneously when introduced into water or when chewing, but with a time delay (“controlled release”).

It is thus well known that ingredients such as fragrances, insecticides, odor-counteracting substances, fungicides and mildewicides and the like can be encapsulated in a microcapsule that includes a solid shell or membrane that protects them from their immediate environment. A popular method for making such encapsulated formulations is to disperse the ingredient in a liquid and create a polymer membrane on the surface of the droplets. Examples of suitable methods include the simple and complex coacervation of gelatin with gum arabic, followed by crosslinking with glutaraldehyde. In principle, many polymers or polymer mixtures that are capable of forming insoluble complexes under specific conditions can be used to form such interface membranes by a so-called polymer phase separation process. The most important microcapsules include those of the aminoplast type. The production of these capsules is simplified by first producing an O / W emulsion with strong shear and in the presence of emulsifiers, which contains the water-soluble monomer, a so-called amine-formaldehyde precondensate, and the water-insoluble active ingredient, such as a perfume oil . The polycondensation is initiated by a change in pH, for example by adjusting the pH to about 3.5 by adding acid. The polycondensates deposit on the oil droplets in the emulsion and gradually envelop them. After the polycondensation had ended, a microcapsule dispersion resulted from the emulsion. However, the capsules still have a soft, elastic shell, which does not yet provide the necessary diffusion stability and texture properties. The third step then follows, in which the temperature is raised to about 60 ° C., which leads to crosslinking of the polymers in the wall and hardening of the capsules. A corresponding method is known for example from EP 2111214 B1 (GIVAUDAN).

The problem here, however, is that the capsules described above are so stable that the encapsulated active ingredient, such as perfume oil, is not released in time to obtain a satisfactory result. In addition, free, non-encapsulated perfume oil must be used, which causes additional effort and costs, since this perfume oil differs from the encapsulated perfume oil with regard to various properties such as strength and quality.

Another strategy is the so-called "scratch-and-sniff" system. When applied to perfumes, these microcapsules are typically used to produce surprising sensory effects, such as increased perfume intensity or impact, at a time when the microcapsules are broken open by the action of pressure or friction. A disadvantage of this system, however, is that the capsules generally suffer from serious stability problems, such as the extraction of the perfume due to the conjugated action of the surfactants, especially after prolonged storage at elevated temperatures. This leads to a loss of perfume. This can be avoided by strengthening the wall of the microcapsules by various means, such as, for example, increasing the crosslink density of the wall or applying a coating thereon. However, this generally leads to an increase in the stress required to break the microcapsules and consequently complicates the release of the encapsulated fragrance. The invention is therefore based on the object to overcome the disadvantages of the prior art. In particular, the invention is based on the object of providing microcapsules which are distinguished by a high diffusion density and at the same time have an easily breakable capsule wall, in order thus to ensure the sufficient release of the encapsulated active ingredient.

DESCRIPTION OF THE INVENTION

[0008] This object is fully achieved by the present claims. A first subject of the invention relates to microcapsules comprising

(a) a core containing at least one active ingredient, and

(b) a capsule wall, wherein the capsule wall consists of at least three polymer layers and at least one of the polymer layers consists of a first phenolic resin, the first phenolic resin comprising 3 to 50% by weight of groups derived from at least one aromatic polyol and at least one further the polymer layers consist of a second phenolic resin, the second phenolic resin comprising 3 to 50% by weight of groups derived from at least one triphenol.

Surprisingly, it was found that the microcapsules according to the invention are particularly stable to diffusion but nevertheless have a capsule wall which ensures release of the active ingredient contained in the end product even with very little to no friction, but which are nevertheless stable in storage. This is ensured by the capsule wall having at least three polymer layers, one of the three polymer layers consisting of a first phenolic resin, the first phenolic resin comprising groups derived from at least one aromatic polyol and at least one further of the polymer layers consisting of a second phenolic resin , wherein the second phenolic resin comprises groups derived from at least one triphenol. The inner polymer layer in the sense of the invention is the part of the capsule wall which directly adjoins the core of the microcapsule and thus the active ingredient. Adjacent to the inner polymer layer is the middle polymer layer, which also borders on the outer polymer layer. In Fig. 1, the structure of the microcapsule is shown again in an exemplary manner. It goes without saying that the The capsule wall can also contain further layers, which in turn adjoin the outer layer shown in FIG. 1.

Another advantage of the at least three polymer layers is that they are very thin-walled and consequently lead to a generally very thin capsule wall. This naturally also influences the amount of polymer to be used, which is thereby reduced by up to 90% compared to a microcapsule having only one polymer layer, in particular by 50 to 90%. These thin layers are also advantageous because they only require a very small amount of polymer to be used. Of course, this saves additional material costs. In addition, the capsules of the present invention allow the active ingredient to be released quickly, but are nevertheless fully mechanically loadable.

Another advantage is that the adhesion properties of the microcapsules, in particular the adhesion properties to laundry, improve. This is ensured by the capsule wall being composed of at least three polymer layers, the at least three polymer layers each being very thin-walled and at least one of the polymer layers consisting of a first phenolic resin, the first phenolic resin comprising groups derived from at least one aromatic polyol and at least one further of the polymer layers consists of a second phenolic resin, the second phenolic resin comprising groupings which are derived from at least one triphenol

The surface charge of the capsule itself changes, which ensures better adhesion to anionic substances such as cotton.

As already described in the object of the invention, the microcapsules are therefore distinguished by the fact that they have a high diffusion density but at the same time have a slightly fragile capsule wall, in order thus to ensure the sufficient release of the encapsulated active ingredient. This is achieved by adding at least one aromatic polyol in at least one polymer layer and adding at least one triphenol in another polymer layer. The addition of the polyol and the triphenol on the one hand results in a high stability of the microcapsules and on the other hand reduces the capsule wall itself, which, as mentioned above, saves costs with regard to the amount of polymer to be used and ensures a release of the active ingredient. The inner layer of the capsule wall preferably consists of a first phenolic resin, the first phenolic resin comprising 3-50% by weight, preferably 5 to 45% by weight, more preferably 10 to 40% by weight, of groups which differ from an aromatic Derive polyol. In other embodiments of the invention, the first phenolic resin can also comprise 30 to 80%, preferably 40 to 75% by weight, preferably 45 to 65% by weight of groups derived from an aromatic polyol. The middle layer of the capsule wall preferably consists of an aminoplast resin, in particular a melamine-formaldehyde resin, the aminoplast resin comprising 3 to 90% by weight, preferably 10 to 85%, preferably 20 to 80% by weight of groups which differ from one another Derive polyamine, especially melamine. The outer layer of the capsule wall preferably consists of a second phenolic resin, the second phenolic resin comprising 3 to 50% by weight, preferably 5 to 45% by weight, further preferably 10 to 40% by weight, of groups derived from a triphenol. In other embodiments of the invention, the second phenolic resin can also comprise 30 to 80%, preferably 40 to 75% by weight, preferably 45 to 65% by weight of groups which are derived from a triphenol.

In one embodiment of the invention, the at least three polymer layers of the capsule wall each consist of resins which comprise groups which are derived from different substances. In a further embodiment of the invention, the at least three polymer layers have an alternating structure, a polymer layer which is composed of a phenolic resin being separated by a polymer layer which is composed of an aminoplast resin, preferably melamine-formaldehyde resin. In a further embodiment of the invention, the at least three polymer layers have an alternating structure, a polymer layer which comprises groupings which are derived from the condensation of phenols or polyols with an aldehyde being in each case separated by a polymer layer which comprises groupings which differ from one another derive from the condensation of polyamines with an aldehyde, in particular formaldehyde. In other words, the present invention also relates to microcapsules comprising

(a) a core containing at least one active ingredient, and

(b) a capsule wall, wherein the capsule wall consists of at least three polymer layers and comprises at least one of the polymer layers groupings which are derived from the condensation of at least one aromatic polyol and at least one aldehyde and at least one further of the polymer layers comprises groupings which result from the condensation of at least one triphenol and derive at least one aldehyde.

For example, a particularly preferred embodiment of the invention can consist of a first polymer layer composed of groups derived from the condensation of resorcinol and aldehyde, a second polymer layer composed of groups derived from the condensation of melamine and aldehyde and a third Polymer layer consisting of groups derived from the condensation of phloroglucin and aldehyde. Or a first from triethanolamine-formaldehyde groups, a second from resorcinol-aldehyde groups and a third from phloroglucin-aldehyde groups. Or a first of melamine-formaldehyde groups, a second of resorcinol-aldehyde groups and a third of phloroglucin-aldehyde groups. Of course, precondensates such as Luracoll ^® SD can also be used instead of an amine-formaldehyde component.

A further particularly preferred embodiment of the invention consists of a first polymer layer consisting of a first phenolic resin, the first phenolic resin comprising groups derived from resorcinol, a second polymer layer consisting of aminoplast resin, the aminoplast resin comprising groups consisting of Derive melamine and a third polymer layer consisting of a second phenolic resin, wherein the second phenolic resin comprises groups derived from phloroglucin. Or a first from triethanolamine-formaldehyde groups, a second from resorcinol groups and a third from phloroglucin groups. Or a first from melamine-formaldehyde groups, a second from resorcinol groups and a third from phloroglucin groups. Of course, precondensates such as Luracoll ^® SD can also be used instead of an amine-formaldehyde component.

By "grouping" or "groupings" is meant a chemical entity that is part of a polymer and is derived from a particular molecule. The polymer layers described above can be any polymer layers that comprise the groupings described above of the many suitable methods known in the art. In other words, the The polymer layers described above consist of different resins, such as, for example, phenol resins or aminoplast resins, in particular melamine-formaldehyde resins, which comprise the groups described above.

For the purposes of the invention, all percentages are percentages by weight, unless specifically stated otherwise.

In a particularly preferred embodiment, the aromatic polyol groups are derived from resorcinol. The terms “resorcinol” or “resorcinol” are synonymous terms and are also used synonymously in the light of the invention.

A triphenol in the sense of the invention is a trihydric phenol, ie a phenol with three hydroxyl groups. Suitable triphenols are, for example, phloroglucin (1,3,5-trihydroxybenzene), pyrogallol (1,2,3-trihydroxybenzene) or hydroxyhydro smell (1,2,4-trihydroxybenzene). Preferred triphenols are 1, 3, 5-triaminoalkylbenzene and phloroglucin. In a preferred embodiment of the invention, the outer polymer layer of the capsule wall consists of a second phenolic resin, the second phenolic resin comprising a group which is derived from at least one triphenol. The particularly preferred triphenol is phloroglucin.

In a preferred embodiment of the invention, the capsule wall consists of three polymer layers. In a further preferred embodiment of the invention, the three polymer layers of the capsule wall each consist of different resins, the resins comprising groups which are derived from different substances. In a preferred embodiment, the outer polymer layer consists of a second phenolic resin, the second phenolic resin comprising groups which are derived from phloroglucinol. In a further preferred embodiment, the middle polymer layer consists of an aminoplast resin, the aminoplast resin comprising groups which are derived from a mixture of melamine and formaldehyde. In a further preferred embodiment, the inner polymer layer consists of a first phenolic resin, the first phenolic resin comprising groups which are derived from resorcinol. The simultaneous use of groups which are derived from resorcinol and phloroglucin in different polymer layers is also particularly advantageous since this enables the formation of a three-layer capsule wall, which also meets all requirements such as stability, efficient perfume release, etc. As already mentioned above, they are particularly thin Capsule walls enabled. In a particularly preferred embodiment, the outer polymer layer consists of a second phenolic resin, the second phenolic resin comprising groups derived from phloroglucin and the middle polymer layer consisting of an aminoplast resin, the amino resin comprising groups derived from mixtures of melamine and formaldehyde and the inner polymer layer made of a first phenolic resin, the first phenolic resin comprising groups derived from resorcinol.

In one embodiment of the invention, the inner polymer layer of the microcapsule according to the invention is a first phenolic resin, the first phenolic resin comprising groups which are derived from at least one aromatic polyol. In a preferred embodiment, the groupings comprising the first phenolic resin are derived from resorcinol.

In one embodiment of the invention, the middle polymer layer of the microcapsule according to the invention is an aminoplast resin, in particular a melamine

Formaldehyde resin, the aminoplast resin comprising groups derived from at least one polyamine. In a preferred embodiment, the groupings comprising the aminoplast resin are derived from melamine.

In one embodiment of the invention, the outer polymer layer of the microcapsule according to the invention is a second phenolic resin, the second phenolic resin comprising groups which are derived from at least one triphenol. In a preferred embodiment, the groupings comprising the second phenolic resin are derived from phloroglucin.

Phenolic resins in the sense of the invention are synthetic resins (condensation resins) which are produced by polycondensation from phenols and aldehydes. Important starting materials for the production of the resins are, for example, phenol and formaldehyde. Aminoplast resins in the sense of the invention are curable synthetic resins which are produced by polycondensation of aldehydes and compounds with NH or NH2 groups, such as, for example, urea, melamine or dicyandiamide. In a particularly preferred embodiment of the invention, formaldehyde is used as the Aldeyhd.

In a further preferred embodiment, the capsule wall content based on the slurry is 0.3 to 3% by weight. In a further preferred embodiment of the invention the portion of the capsule wall based on the slurry is 0.3 to 2% by weight. In a further preferred embodiment of the invention, the capsule wall content, based on the slurry, is 0.3 to 0.9% by weight. Microcapsules of the type described above are provided in the form of a slurry with a solids content of typically 20 to 50%, preferably 30 to 45%, the term "solids content" referring to the total weight of the microcapsules. The average size of the microcapsules can range from 1 micron to 100 microns or more. The selection of the most suitable microcapsule size range and size distribution depends on the intended application.

[0027] A “slurry” in the sense of the invention is nothing more than a suspension in water. A synonymous term would also be “slurry”, for example.

In a further preferred embodiment of the invention, the capsule wall proportion, based on the active ingredient, in particular on the perfume oil, is 0.5 to 7% by weight. In a further preferred embodiment of the invention, the

Capsule wall content based on the active ingredient, in particular on the perfume oil 0.5 to 5% by weight. In a further preferred embodiment of the invention, the

Capsule wall content based on the active ingredient, in particular on the perfume oil 0.5 to 4% by weight. In a further preferred embodiment of the invention, the

Capsule wall content based on the active ingredient, in particular on the perfume oil 0.7 to 4% by weight. In a further preferred embodiment of the invention, the

Capsule wall content based on the active ingredient, in particular on the perfume oil 0.7 to 3% by weight.

POLYAMINE / PRE-CONDENSATE

Preferred polyamines for the purposes of the invention are so-called polyamine precondensates, in particular amine-formaldehyde precondensates or precondensates (AFP). In a preferred embodiment, these form the material which finally forms the shell or wall of the capsule by polycondensation and encloses the active ingredient. For the purposes of the invention, the terms precondensates or precondensates can be used synonymously.

The amine component of the AFP is usually fluorine or in particular melamine. However, since the polycondensation is thermally controlled, it is Control is sometimes difficult. Generally, aminoplasts are made by polycondensing formaldehyde with compounds containing two or more amino groups (e.g. urea, thiourea, melamine, cyanamide, diaminohexane, benzoguanamine). In a first step, this reaction proceeds via the addition of urea to form N-hydroxymethyl groups and then chain growth via polycondensation with elimination of water. This reaction is usually carried out in basic solution, since OH ions are required as a catalyst and uncrosslinked precondensates are formed. The precondensates are stable for several months at room temperature. The preferred AFPs are therefore alkylation products of melamine with short-chain alcohols and in particular the so-called highly or partially alkoxylated and optionally also alkylated melamines, such as those offered by BASF in aqueous methanolic formaldehyde solution under the name Luracoll ^® , in particular Luracoll ^® SD.

The reaction between melamine and formaldehyde, for example, was already discovered by J. Liebig in 1834 and has been used industrially since 1936. It can be described by the following scheme:

Preferred polyamines are: optionally alkylated mono- and polymethylol-urea and mono- and polymethylol-melamine precondensates, such as those marketed under the name URAC (Cytec Corp.) or partially methylated mono- and Polymethylol-l, 3,5-triamino-2,4,6-triazine precondensates, the are commercially available under the name CYMEL (Cytec Corp.). Finally, mono- and polyalkylolbenzoguanamine or mono- and polyalkylolglycuril precondensates are also suitable. If these precondensates have alkyl groups, they are less reactive and can be stored longer. The preferred precondensates include the polymethylolmelamines and the polymethylol-l- (3,5-dihydroxy-methylbenzyl) -3,5-triamino-2,4,6-triazine.

Poly [N- (2,2-dimethoxy-l-hydroxy)] - polyamines such as, for example, di- [N- (2,2-dimethoxy-l-hydroxy)] urea, tri- [N - (2,2-dimethoxy-l-hydroxy)] melamine, tetra- [N- (2,2-dimethoxy-l-hydroxy)] glycouryl and di- [N- (2,2-dimethoxy-l- hydroxy)] benzoguanidine and mixtures thereof.

In a particularly preferred embodiment, the polyamines are melamine-formaldehyde directly and / or Luracoll ^® SD as the pre-condensate.

ACTIVE SUBSTANCES

[0035] The selection of the raw materials to be encapsulated is not critical per se and is determined exclusively by the desired application. The only limitation is that these are either in the form of an oil or must be sufficiently oil-soluble, that is, lipophilic, in order to be soluble in an oil phase, preferably together with the aromatic polyol.

In addition to flavors for the food sector, the active substances in particular include perfume oils and oil-soluble fragrances, as listed below by way of example:

Extracts from natural raw materials, such as essential oils, concretes, absolutes, resins, resinoids, balms, tinctures such as. B. ambratincture; Amyris oil; Angelica seed oil; Angelica root oil; Anise oil; Valerian oil; Basil oil; Tree moss absolute; Bay oil; Mugwort oil; Benzoresin; Bergamot oil; Beeswax absolute; Birch tar oil; Bitter almond oil; Savory oil; Bucco leaf oil; Cabreuva oil; Cade oil; Calmus oil; Camphor oil; Cananga oil; Cardamom oil; Cascarilla oil; Cassia oil; Cassie absolute; Castoreum absolute; Cedar leaf oil; Cedarwood oil; Cistus oil; Citronell oil; Lemon oil; Copaiva balm; Copaiva balsam oil; Coriander oil; Costus root oil; Cumin oil; Cypress oil; Davana oil; Dill herb oil; Dill seed oil; Eau de brouts-absolute; Oakmoss absolute; Elemi oil; Tarragon oil; Eucalyptus Citriodora Oil; Eucalyptus oil; Fennel oil; Spruce needle oil; Galbanum oil; Galbanumresin; Geranium oil; Grapefruit oil; Guaiac wood oil; Gurjun balm; Gurjun balsam oil, Helichrysum absolute; Helichrysum oil; Ginger oil; Iris root absolute; Iris root oil; Jasmine absolute; Calamus oil; Chamomile oil blue; Roman chamomile oil; Carrot seed oil; Cascilla oil; Pine oil; Spearmint oil; Caraway oil; Labdanum oil; Labdanum absolute; Labdanumresin; Lavandin absolute; Lavandin oil; Lavender absolute; Lavender oil; Lemongrass oil; Loving stick oil; Distilled lime oil; Lime oil pressed; Linal oil; Litsea Cubeba Oil; Bay leaf oil; Mace oil; Marjoram oil; Mandarin oil; Massoir oil; Mimosa absolute; Musk seed oil; Musk tincture; Muscat Sage Oil; Nutmeg oil; Myrrh absolute; Myrrh oil; Myrtle oil; Clove leaf oil; Clove flower oil; Neroli oil; Olibanum absolute; Olibanum oil; Opopanax oil; Orange blossom absolute; Orange oil; Original oil; Palmarosa oil; Patchouli oil; Perilla oil; Peru balsam oil; Parsley leaf oil; Parsley seed oil; Petitgrain oil; Peppermint oil; Pepper oil; Allspice oil; Pine oil; Poley oil; Rose absolute; Rosewood oil; Rose oil; Rosemary oil; Dalmatian sage oil; Sage oil spanish; Sandalwood oil; Celery seed oil; Spiklavendel oil; Star anise oil; Styrax oil; Tagetes oil; Pine needle oil; Tea tree oil; Turpentine oil; Thyme oil; Tolu balm; Tonka Absolu; Tuberose absolute; Vanilla extract; Violet leaf absolute; Verbena oil; Vetiver oil; Juniper berry oil; Wine yeast oil; Wormwood oil; Wintergreen oil; Ylang oil; Hyssop oil; Civet absolute; Cinnamon leaf oil; Cinnamon bark oil; and fractions thereof or ingredients isolated therefrom;

Individual odoriferous substances from one or more of the following groups:

Hydrocarbons, such as. B. 3-carene; a-pinene; beta -pinene; alpha terpinene; gamma terpinene; p-cymene; Bisabolene; Camphene; Caryophyllene; Cedren; Farnese; Lime; Longifolene; Myrcene; Ocimen; Valencene; (E, Z) -l, 3,5-undecatriene;

Aliphatic alcohols, such as. B. hexanol; Octanol; 3-octanol; 2,6-dimethylheptanol; 2-methylheptanol, 2-methyloctanol; (E) -2-hexenol; (£ ^" ) - and (Z) -3-hexenol; l-octen-3-ol; mixture of 3,4,5,6,6-pentamethyl-3/4-hepten-2-ol and 3,5, 6,6-tetramethyl-4-methyleneheptan-2-ol; (£, Z) -2,6-nonadienol; 3,7-dimethyl-7-methoxyoctan-2-ol; 9-decenol; 10-undecenol; 4- Methyl-3-decen-5-ol;

Aliphatic aldehydes and their acetals, such as. B. Hexanal; Heptanal; Octanal; Nonanal; Decanal; Undecanal; Dodecanal; Tridecanal; 2-methyloctanal; 2-methyl nonanal; (£) -2-hexenal; (Z) -4-heptenal; 2,6-dimethyl-5-heptenal; 10-undecenal; (£) -4-decenal; 2- dodecenal; 2,6,10-trimethyl-5,9-undecadienal; Heptanal diethylacetal; l, l-dimethoxy-2,2,5-trimethyl-4-hexene; Citronellyloxyacetaldehyde; Aliphatic ketones and their oximes, such as. B. 2-heptanone; 2-octanone; 3-octanone;

2-nonanone; 5-methyl-3-heptanone; 5-methyl-3-heptanone oxime; 2,4,4,7-tetramethyl-6-octene

3-one;

Aliphatic sulfur-containing compounds, such as. B. 3-methylthiohexanol; 3-methylthiohexyl acetate; 3-mercaptohexanol; 3-mercaptohexyl acetate; 3-mercaptohexyl butyrate; 3-acetylthiohexyl acetate; l-menthen-8-thiol;

Aliphatic nitriles, such as. B. 2-Nonenonitrile; 2-tridecenonitrile; 2,12-tridecenonitrile; 3,7-dimethyl-2,6-octadienonitrile; 3,7-dimethyl-6-octenonitrile;

Aliphatic carboxylic acids and their esters, such as. B. (£) - and (Z) -3-hexenyl formate; Ethyl acetoacetate; Isoamyl acetate; Hexyl acetate; 3,5,5-trimethylhexyl acetate; 3-methyl-2-butenyl acetate; (£) -2-hexenyl acetate; (£) - and (Z) -3-hexenyl acetate; Octyl acetate; 3-octyl acetate; l-octen-3-ylacetate; Ethyl butyrate; Butyl butyrate; Isoamyl butyrate; Hexyl butyrate; (E) - and (Z) -3- hexenyl isobutyrate; Hexyl crotonate; Ethyl isovalerate; Ethyl 2-methylpentanoate; Ethyl hexanoate; Allyl hexanoate; Ethyl heptanoate; Allyl heptanoate; Ethyl octanoate; Ethyl (£, Z) -2,4-decadienoate; Methyl 2-octinate; Methyl 2-noninate; Allyl-2-isoamyloxyacetate; Methyl 3,7-dimethyl-2,6-octadienoate;

Acyclic terpene alcohols, such as. B. Citronellol; Geraniol; Nerol; Linalool; Lavadulol; Nerolidol; Farnesol; Tetrahydrolinalool; Tetrahydrogeraniol; 2,6-dimethyl-7-octen-2-ol; 2,6-dimethyloctan-2-ol; 2-methyl-6-methylene-7-octen-2-ol; 2,6-dimethyl-5,7-octadien-2-ol; 2,6-dimethyl-3,5-octadien-2-ol; 3,7-dimethyl-4,6-octadien-3-ol; 3,7-dimethyl-1,5,7-octatrien-3-ol; 2,6-dimethyl-2,5,7-octatrien-l-ol; as well as their formates, acetates, propionates, isobutyrates, butyrates, isovalerianates, pentanoates, hexanoates, crotonates, tiglinates, 3-methyl-2-butenoates;

Acyclic terpene aldehydes and ketones, such as. B. Geranial; Neral; Citronellal; 7-hydroxy-3,7-dimethyloctanal; 7-methoxy-3,7-dimethyloctanal; 2,6,10-trimethyl-9-undecenal; Geranylacetone; as well as the dimethyl and diethyl acetals of geranial, neral, 7-hydroxy-3,7-dimethyloctanal;

Cyclic terpene alcohols, such as. B. menthol; Isopulegol; a-terpineol; Terpinenol-4; Menthan-8-ol; Menthan-l-ol; Menthan-7-ol; Borneol; Isoborneol; Linalool oxide; Nopol; Cedrol; Ambrinol; Vetiverol; Guajol; as well as their formates, acetates, propionates, isobutyrates, butyrates, isovalerianates, pentanoates, hexanoates, crotonates, tiglinates, 3-methyl-2-butenoates; Cyclic terpene aldehydes and ketones, such as. B. Menthon; Isomenthon; 8-mercaptomenthan-3-one; Carvon; Camphor; Fenchone; a-lonon; beta-ionone; an-methyl ionone; beta -n-methylionone; a-isomethylionone; beta isomethyl ionone; a-lron; a- Damascon; beta -Damascon; beta-damascenon; ? -Damascon; d-Damascon; l- (2,4,4-trimethyl-2-cyclohexen-l-yl) -2-buten-l-one; 1, 3,4,6, 7,8a-hexahydro-1,1,5,5-tetramethyl-2H-2,4a-methanonaphthalene-8 (5H) -one; Nootcat; Dihydronootcatone; a-Sinensal; beta - Sinensal; acetylated cedarwood oil (methyl cedryl ketone);

Cyclic alcohols, such as. B. 4-te / t-butylcyclohexanol; 3,3,5-trimethylcyclohexanol;

3-isocamphylcyclohexanol; 2,6,9-trimethyl- (Z2, Z5, £ 9) -cyclododecatrien-l-ol; 2-isobutyl-4-methyltetrahydro-2H-pyran-4-ol;

From the group of cycloaliphatic alcohols such as. B. a, 3,3-trimethylcyclohexylmethanol; 2-methyl-4- (2,2,3-trimethyl-3-cyclopent-l-yl) butanol; 2-methyl-4- (2,2,3-trimethyl-3-cyclopent-l-yl) -2-buten-l-ol; 2-ethyl-4- (2,2,3-trimethyl-3-cyclopent-l-yl) -2-buten-l-ol; 3-methyl-5- (2,2,3-trimethyl-3-cyclopent-l-yl) pentan-2-ol; 3-methyl-5- (2,2,3-trimethyl-3-cyclopent-l-yl) -4-penten-2-ol; 3,3-dimethyl-5- (2,2,3-trimethyl-3-cyclopent-l-yl) -

4-penten-2-ol; 1- (2,2,6-trimethylcyclohexyl) pentan-3-ol; 1- (2,2,6-trimethylcyclohexyl) hexan-3-ol;

Cyclic and cycloaliphatic ethers, such as. B. Cineol; Cedryl methyl ether; Cyclododecyl methyl ether; (Ethoxymethoxy) cyclododecane; a-cedrenepoxide; 3a, 6, 6, 9a-tetramethyldodecahydronaphtho [2, l-b] furan; 3a-ethyl-6,6,9a-trimethyl-dodecahydronaphtho [2, l-b] furan; 1,5,9-trimethyl-13-oxabicyclo [10.1.0] trideca-4,8-diene; Rose oxide; 2- (2,4-dimethyl-3-cyclohexen-l-yl) -5-methyl-5- (l-methylpropyl) -l, 3-dioxane;

Cyclic ketones, such as. B. 4-tert-butylcyclohexanone; 2,2,5-trimethyl-5-pentylcyclopentanone; 2-heptylcyclopentanone; 2-pentylcyclopentanone; 2-hydroxy-3-methyl-2-cyclopenten-l-one; 3-methyl-cis-2-penten-l-yl-2-cyclopenten-l-one; 3-methyl-2-pentyl-2-cyclopenten-l-one; 3-methyl-4-cyclopentadecenone; 3-methyl-5-cyclopentadecenone; 3-methylcyclopentadecanone; 4- (l-ethoxyvinyl) -3,3,5,5-tetramethylcyclohexanone; 4-tert-pentylcyclohexanone; 5-cyclohexadecen-1-one; 6,7-dihydro-l, l, 2,3,3-pentamethyl-4 (5H) - indanon; 9-cycloheptadecen-1-one; Cyclopentadecanone; Cyclohexadecanone;

Cycloaliphatic aldehydes, such as. B. 2,4-dimethyl-3-cyclohexenecarbaldehyde; 2-methyl-4- (2,2,6-trimethyl-cyclohexen-1-yl) -2-butenal; 4- (4-hydroxy-4-ethylpentyl) -3-cyclohexenecarbaldehyde; 4- (4-methyl-3-penten-l-yl) -3-cyclohexenecarbaldehyde; Cycloaliphatic ketones, such as. B. l- (3,3-Dimethylcyclohexyl) -4-penten-l-one; l- (5,5-dimethyl-l-cyclohexen-l-yl) -4-penten-l-one; 2,3,8,8-tetramethyl-l, 2,3,4,5,6,7,8-octahydro-

2-naphthalenyl methyl ketone; Methyl 2,6,10-trimethyl-2,5,9-cyclododecatrienyl ketone; tert-

Butyl- (2,4-dimethyl-3-cyclohexen-l-yl) ketone;

Esters of cyclic alcohols, such as. B. 2-tert-butylcyclohexyl acetate; 4-tert-butylcyclohexyl acetate; 2-th / t-pentylcyclohexyl acetate; 4-th / t-pentylcyclohexyl acetate; Decahydro-2-naphthyl acetate; 3-pentyltetrahydro-2H-pyran-4-ylacetate; Decahydro-2,5,5,8a-tetramethyl-2-naphthyl acetate; 4,7-methano-3a, 4,5,6,7,7a-hexahydro-5- or -6-indenyl acetate; 4,7-methano-3a, 4,5,6,7,7a-hexahydro-5- or -6-indenylpropionate; 4,7-methano-3a, 4,5,6,7,7a-hexahydro-5- or -6-indenyl isobutyrate; 4,7-methanooctahydro-5- or -6-indenyl acetate;

Esters of cycloaliphatic carboxylic acids, such as. B. allyl-3-cyclohexylpropionate; Allylcyclohexyloxyacetate; Methyl dihydrojasmonate; Methyl jasmonate; Methyl 2-hexyl-3-oxocyclopentane carboxylate; Ethyl 2-ethyl-6,6-dimethyl-2-cyclohexenecarboxylate; Ethyl 2, 3,6,6-tetramethyl-2-cyclohexenecarboxylate; Ethyl 2-methyl-1,3-dioxolane-2-acetate;

Aromatic hydrocarbons, such as. B. styrene and diphenylmethane;

Araliphatic alcohols, such as. B. benzyl alcohol; 1-phenylethyl alcohol; 2-phenylethyl alcohol; 3-phenylpropanol; 2-phenylpropanol; 2-phenoxyethanol; 2,2-dimethyl

3-phenylpropanol; 2,2-dimethyl-3- (3-methylphenyl) propanol; l, l-dimethyl-2-phenylethyl alcohol; l, l-dimethyl-3-phenylpropanol; l-ethyl-l-methyl-3-phenylpropanol; 2-methyl-5-phenylpentanol; 3-methyl-5-phenylpentanol; 3-phenyl-2-propen-l-ol; 4-methoxybenzyl alcohol; 1- (4-isopropylphenyl) ethanol;

Esters of araliphatic alcohols and aliphatic carboxylic acids, such as. B.

Benzyl acetate; Benzyl propionate; Benzyl isobutyrate; Benzyl isovalerate; 2-phenylethyl acetate; 2-phenylethyl propionate; 2-phenylethyl isobutyrate; 2-phenylethyl isovalerate; 1-phenyl ethyl acetate; a-trichloromethylbenzyl acetate; a, a-dimethylphenylethyl acetate; a, a-dimethylphenylethyl butyrate; Cinnamate acetate; 2-phenoxyethyl isobutyrate; 4-methoxybenzyl acetate;

Araliphatic ether, such as. B. 2-phenylethyl methyl ether; 2-phenylethyl isoamyl ether; 2-phenylethyl-1-ethoxyethyl ether; Phenylacetaldehyde dimethyl acetal;

Phenylacetaldehyde diethylacetal; Hydratropaaldehyde dimethyl acetal; Phenylacetaldehyde glycerol acetal; 2,4,6-trimethyl-4-phenyl-1,3-dioxanes; 4,4a, 5,9b-tetrahydroindeno [1,2-d] -m-dioxin; 4,4a, 5,9b-tetrahydro-2,4-dimethylindeno [1,2-d] -m-dioxin; Aromatic and araliphatic aldehydes, such as. B. Benzaldehyde; Phenylacetaldehyde; 3-phenylpropanal; Hydratropaaldehyde; 4-methylbenzaldehyde; 4-methylphenylacetaldehyde; 3- (4-ethylphenyl) -2,2-dimethylpropanal; 2-methyl-3- (4-isopropylphenyl) propanal; 2-methyl-3- (4-te / t-butylphenyl) propanal; 3- (4-te / t-butylphenyl) propanal; Cinnamaldehyde; a-butyl cinnamaldehyde; a-amylcinnamaldehyde; a-hexylcinnamaldehyde; 3-methyl-5-phenylpentanal; 4-methoxybenzaldehyde; 4-hydroxy-3-methoxybenzaldehyde; 4-hydroxy-3-ethoxybenzaldehyde; 3,4-methylenedioxybenzaldehyde; 3,4-dimethoxybenzaldehyde; 2-methyl-3- (4-methoxyphenyl) propanal; 2-methyl-3- (4-ethylenedioxyphenyl) propanal;

Aromatic and araliphatic ketones, such as. B. acetophenone; 4-methyl acetophenone; 4-methoxyacetophenone; 4-te / t-butyl-2,6-dimethylacetophenone; 4-phenyl-2-butanone; 4- (4-hydroxyphenyl) -2-butanone; 1- (2-naphthalenyl) ethanone; Benzophenone; l, l, 2,3,3,6-hexamethyl-5-indanyl methyl ketone; 6-te / t-butyl-l, l-dimethyl-4-indanylmethyl ketone; l- [2,3-dihydro-1,2,2 _; 6-tetramethyl-3- (1-methylethyl) -IH-5-indenyl] ethanone;

S ^ e '^ S'-tetrahydro-S' ^ S '^ S ^ S'-hexamethyl-Z-acetonaphthon;

Aromatic and araliphatic carboxylic acids and their esters, such as. B.

Benzoic acid; Phenylacetic acid; Methyl benzoate; Ethyl benzoate; Hexyl benzoate; Benzyl benzoate; Methylphenylacetate; Ethylphenylacetate; Geranylphenyl acetate; Phenylethylphenyl acetate; Methyl cinnamate; Ethyl cinnamate; Benzyl cinnamate; Phenylethyl cinnamate; Cinnamyl cinnamate; Allylphenoxyacetate; Methyl salicylate; Isoamyl salicylate; Hexyl salicylate; Cyclohexyl salicylate; c / s-3-hexenyl salicylate; Benzyl salicylate; Phenylethyl salicylate; Methyl 2,4-dihydroxy-3,6-dimethylbenzoate; Ethyl 3-phenylglycidate; Ethyl 3-methyl-3-phenylglycidate;

Nitrogen-containing aromatic compounds, such as. B. 2 _/ 4,6-trinitro-l _/ 3-dimethyl-5-tert-butylbenzene; 3,5-dinitro-2,6-dimethyl-4-tert-butylacetophenone; Cinnamic acid nitrile; 5-phenyl-3-methyl-2-pentenenenitrile; 5-phenyl-3-methylpentanoic acid nitrile;

Methyl anthranilate; Methyl-N-methylanthranilate; Schiff bases of methylanthranilate with 7-hydroxy-3,7-dimethyloctanal, 2-methyl-3- (4-tert-butylphenyl) propanal or 2,4-dimethyl-3-cyclohexenecarbaldehyde; 6-isopropylquinoline; 6-isobutylquinoline; 6-sec-butylquinoline; Indole; Skatole; 2-methoxy-3-isopropylpyrazine; 2-isobutyl-3-methoxypyrazine; 4- (4,8-dimethyl-3,7-nonadienylj-pyridine;

Phenols, phenyl ethers and phenyl esters, such as. B. Estragol; Anethole; Eugenol; Eugenyl methyl ether; Isougenol; Isougenyl methyl ether; Thymol; Carvacrol; Diphenyl ether; beta -naphthyl methyl ether; beta -naphthyl ethyl ether; beta -naphthyl isobutyl ether; 1.4- Dimethoxybenzene; Eugenyl acetate; 2-methoxy-4-methylphenol; 2-ethoxy-5- (l-propenyl) phenol; p-cresylphenylacetate;

From the group of heterocyclic compounds such. B. 2,5-dimethyl-4-hydroxy-2H-furan-3-one; 2-ethyl-4-hydroxy-5-methyl-2H-furan-3-one; 3-hydroxy-2-methyl-4H-pyran-4-one; 2-ethyl-3-hydroxy-4H-pyran-4-one;

Lactones, such as. B. 1,4-octanolide; 3-methyl-1,4-octanolide; 1,4-nonanolide; 1,4-decanolide; 8-decene-1,4-olide; 1,4-undecanolide; 1,4-dodecanolide; 1,5-decanolide; 1,5-dodecanolide; 1,15-pentadecanolide; cis- and trans-ll-pentadecene-1,15-olide; cis- and trans-12-pentadecene-1,15-olide; 1,16-hexadecanolide; 9-hexadecen-l, 16-olide; 10-oxa-l, 16-hexadecanolide; ll-oxa-l, 16-hexadecanolide; 12-oxa-1,16-hexadecanolide; Ethylene 1,12-dodecanedioate; Ethylene-l, 13-tridecanedioate; Coumarin; 2,3-dihydrocoumarin; Octahydrocu marine.

STABILIZERS AND PROTECTIVE COLLOIDS

Preferably, the emulsions additionally contain stabilizers or protective colloids. Suitable examples include, in particular acrylic copolymers that have sulfonate groups, such as LUPASOL ^® PA140 or LUPASOL VFR ^® (BASF). Also suitable are copolymers of acrylamides and acrylic acid, copolymers of alkyl acrylates and N-vinylpyrrolidone such as LUVISKOL ^® K15, K30 or K90 (BASF); Sodium polycarboxylates, sodium polystyrene sulfonates, vinyl and methyl vinyl ether-maleic anhydride copolymers as well as ethylene, isobutylene or styrene-maleic anhydride copolymers.

The preferred stabilizers are the representatives of the LUPASOL ^® series mentioned above, in particular in combination with AFP of the LURACOLLL ^® type.

The amount of stabilizers used can be in the range from approximately 1 to approximately 10% by weight and in particular approximately 2 to approximately 5% by weight, based on the emulsion.

The use of stabilizers during the production of the microcapsules according to the invention can be advantageous, since this additionally reduces possible color changes. PRODUCTION METHOD

Another object of the present invention is a method for producing the microcapsules described above, comprising the following steps:

(a) provision of a first aqueous preparation comprising at least one aldehyde or at least one polyamine precondensate;

(b) providing an oil phase containing the active ingredient to be encapsulated and at least one aromatic polyol;

(c) Mixing the aqueous phase with the oil phase in the presence

at least one emulsifier and / or stabilizer to form an emulsion;

(d) Start the polymerization.

(e) adding at least one polyamine or a polyamine precondensate;

(f) resting the mixture at 40 to 70 ° C for 40 to 80 minutes;

(g) adding at least one triphenol;

(h) adding at least one aldehyde or at least one

Polyamine precondensate;

(i) resting the mixture at 40 to 70 ° C for 40 to 80 minutes;

(j) crosslinking and hardening the microcapsules obtained and

possibly

(k) separating and drying the microcapsules from the dispersion.

It is important here that the aromatic polyol from step (b) is added to the oil phase. This has the advantage that higher storage stability can be achieved despite the thinner capsule wall overall. In a preferred embodiment of the invention, the mixture in step (f) rests at 50 to 65 ° C for 50 to 70 minutes. In a very preferred embodiment, the mixture in step (f) is at about 60 ° C. for about 60 minutes. In a preferred embodiment of the invention, the mixture in step (i) rests at 50 to 65 ° C for 50 to 70 minutes. In a very preferred embodiment, the mixture in step (f) is at about 60 ° C. for about 60 minutes.

In one embodiment of the invention, the reaction with CO 2 is additionally superimposed after step (c). This overlay with C02 has the advantage that discoloration, which is caused by aromatic polyols in the core, is reduced.

All of the polyamines listed above (step (e)) or precondensates (step (a) and (e) can be used in the process according to the invention. In a preferred embodiment of the invention, polyamines precondensates are used which are selected from the group consisting of is formed from optionally alkylated mono- and polymethylol-urea or mono- and polymethylol-melamine precondensates, partially methylated mono- and polymethylol-1, 3,5-triamino-2,4,6-triazine precondensates, mono- and Polyalkylolbenzoguanamine and mono- and polyalkylolglycuril precondensates, poly [N- (2,2-dimethoxy-l-hydroxy)] polyamines, melamine-formaldehyde, Luracoll SD and mixtures thereof.

In a particularly preferred embodiment, formaldehyde is used in step (a) as the aldehyde. In a further particularly preferred embodiment, Luracoll SD is used as the polyamine / precondensate in step (e).

All of the active ingredients listed above can be used in the production process according to the invention. In a preferred embodiment of the invention, a perfume oil is used as the active ingredient to be encapsulated.

In one embodiment of the invention, the mixture is heated to 80 ° C. to 90 ° C. directly after step (i). This step serves to form the outer polymer layer of the capsule wall. In a particularly preferred embodiment, the triphenol is phloroglucinol.

In a further embodiment of the invention, at the start of the polymerization in step (d), the pH is reduced to a value from 3 to 5 by adding formic acid or a mixture of formic acid, citric acid and ascorbic acid. This lowering of the pH value in turn serves to prevent unwanted color reactions of the aromatic polyol. Color reactions are of course not, especially with regard to the use of the microcapsules, for example in fabric softener desired and must be avoided as much as possible. This is possible by the described lowering of the pH at the start of the polymerization of the first polymer layer.

In a further embodiment of the invention, the addition of at least one aromatic polyol in step (b) and the addition of at least one triphenol in step (g) enables the formation of at least three polymer layers and also the formation of an overall very thin capsule wall. This is possible, although the capsule wall in the sense of the invention consists of at least three polymer layers. Compared to microcapsules consisting of 1 or 2 layers, thinner capsule walls are formed, which saves material costs but at the same time ensures better stability. In a preferred embodiment of the invention, the aromatic polyol is resorcinol and the triphenol is phloroglucinol.

All substances described in the prior art can be used for crosslinking or curing the capsules. Examples of crosslinkers in the sense of the invention are valeraldehyde, capronaldehyde, caprylaldehyde, decanal, succindialdehyde, cyclohexanecarbaldehyde, cyclopentanecarbaldehyde, 2-methyl-l-propanal, 2-methylpropionaldehyde, acetaldehyde, acrolein, aldosterone, antimycin A, 8-apoteno-δ-apoteno -8- al, Benzaldehyde, Gutanal, Chloral, Citral, Citronellal, Crotonaldehyde, Dimethylaminobenzaldehyde, Folinic acid, Fosmidomycin, Furfural, Glutaraldehyde, Glyceraldehyde, Glycolaldehyde, Glyoxal, Glyoxylic acid, Heptanal, 2-Hydroxybenzaldehyde, 3-Hydroxybutynal, hydroxy , Isobutanal, isobutyraldehyde, methacrolein, 2-methylundecanal, mucochloric acid, N-methylformamide, 2-nitrobenzaldehyde, nonanal, octanal, oleocanthal, orlistat, pentanal, phenylethanal, phycocyanin, piperonal, propanal, propenal, protocatechualaldehyde, retinal, streinal , Strophanthidine, tylosin, vanillin, cinnamaldehyde dimethoxyethanal

An aromatic alcohol also comes from the phenols with two or more hydroxyl groups, preferably from pyrocatechol, resorcinol, hydroquinone and 1,4-naphthohydroquinone, phloroglucinol, pyrogallol, hydroxyhydroquinone. Cresols & phenols, methoxyphenoly, napthols, thymol, ethyl or propylphenols, 1, 3, 5-triaminobenzene, 1, 3, 5-triaminoalkylbenzene, 1, 3, 5-trialkoxyaminobenzene, 1, 3, 5-triamidobenzene. Furthermore, heterocyclic compounds having at least one nitrogen atom as hetero atom, which is adjacent to either an amino-substituted carbon atom or a carbonyl group, such as, for example, pyridazine, pyrimidine, pyrazine, pyrrolidone and aminopyridine and compounds derived therefrom, aminopyridines, for example melamine, can be used as crosslinkers. 2,6-diaminopyridine, substituted and dimeric aminopyridines and mixtures prepared from these compounds, polyamides and dicyandiamide, urea and its derivatives and pyrrolidone and compounds derived therefrom, for example imidazolidinone, hydantoin and its derivatives, allantoin and its derivatives, triamino-1,3. 5-triazine (melamine) into consideration.

It goes without saying that all crosslinkers can be combined with one another.

All other substances or constituents mentioned above can of course also be part of the production process and are not listed again separately.

INDUSTRIAL APPLICABILITY

Another object of the present invention relates to cosmetic preparations, pharmaceutical agents, household and cleaning agents and technical compositions, such as e.g. Adhesive and coating compositions, paints, varnishes, binders, materials such as plastics, paper, textiles, lubricants, building materials, dyes, organic and inorganic powders, pigment dispersions, agrochemicals, phase change materials, flame retardants containing the microcapsules according to the invention.

In a preferred embodiment of the invention, the microcapsules are used in detergents and cleaning agents, cosmetic preparations or perfume compositions. EXAMPLES

Manufacturing process

The production of a capsule according to the invention is described below. This is characterized by the following steps: formation of the first polymer layer:

1. Dissolving the aromatic polyol, preferably the resorcinol in the oil phase of the fragrance, adding formaldehyde to the aqueous phase.

2. Start the polymerization by acidifying to pH 3-5 with formic acid or a mixture of formic acid, citric acid and ascorbic acid to block color reactions.

3. Heat up to 60 ° C to 70 ° C.

4. Optional overlaying the reaction with C02.

Formation of the second polymer layer:

5. Add the polyamine, preferably melamine-formaldehyde or Luracoll SD dissolved in water.

6. Dissolve the protective colloid Lupasol PA140 in water

7. Rest the mixture for 60 min at 60 ° C.

8. Optionally acidify to adjust the pH

Formation of the third polymer layer: 9. Addition of at least one triphenol, preferably phloroglucin

10. Add formaldehyde or Luracoll SD

11. Rest the mixture for 60 min at 60 ° C.

12. Optional heating to 80 ° C - 90 ° C.

13. Then cool to 35 ° C. 14. optional addition of further substances to further harden the capsules. Exemplary compositions of the microcapsules according to the invention are shown in Table 1 below:

Table 1

[0093] Further exemplary production processes:

15 g of Lupasol PA140, 2.5 g of formalin, 37% are dissolved in 120 g of demineralized water and a solution of 180 g of perfume and 1.05 g of resorcinol is added at 35 ° C. while stirring, and about 2 g of 10% formic acid pH 3.5 adjusted. The mixture is then stirred for 30 minutes at 35 ° C. The temperature is then warmed up to 60 ° C. over a period of 30 minutes. 1.7 g melamine and 2.5 g formalin, 37% are added and the mixture is stirred at 60 ° C. for 30 minutes. Finally, 1.5 g of phloroglucin and 2.5 g of formalin, 37%, are added and the mixture is stirred at 60 ° C. for 3 hours.

50 g of formalin, 37%, are dissolved in 60 g of demineralized water. 12.3 g of melamine are dispersed and adjusted to pH 8.0 with about 1 g of triethanolamine and stirred at 70 ° C. until the solution becomes slightly opaque again (about 90 minutes). 60g deionized water, cold are added. A solution of 180 g of perfume and 1.05 g of resorcinol is added with stirring and emulsified. With approx. 30 g citric acid, 25%, a pH of 4.5 is set and the temperature is raised to 40 ° C. At 40 ° C, stirring is continued for 1 h. The mixture is then heated to 60 ° C and stirred it up. Finally, 1.5 g phloroglucin are added and the mixture is stirred at 60 ° C. for 3 hours.

30 g of formalin, 37%, 9 g of urea and about 1 g of triethanolamine are dissolved in 60 g of demineralized water. The pH is adjusted to 8.0 and stirred at 70 ° C. until the solution becomes slightly opaque again (approx. 2 hours). 60g deionized water, cold are added. A solution of 180 g of perfume and 1.05 g of resorcinol is added with stirring and emulsified. With approx. 30 g citric acid, 25%, a pH of 4.0 is set and the temperature is raised to 40 ° C. At 40 ° C, stirring is continued for 1 h. The mixture is then heated to 60 ° C. and stirred for 1 hour. Finally, 1.5 g of phloroglucin are added and the mixture is stirred at 60 ° C. for 3 hours. 15 g of Lupasol PA140 and 2.5 g of paraformaldehyde are dissolved in 120 g of demineralized water, and a solution of 180 g of perfume and 1.05 g of resorcinol is added at 35 ° C. while stirring, and about 2 g of 10% formic acid are added to a pH of 3.5 set. The mixture is then stirred at 35 ° C for 30 minutes. Then the mixture is warmed up to 60 ° C within 30 minutes. 7.5g Luwipal63 is added and the pH is readjusted to 3.5. Then 1.5 g of phloroglucin and 2.5 g of paraformaldehyde are added and the mixture is stirred at 60 ° C. for 1 hour. The temperature is then raised to 80 ° C. and stirred again for 2 hours.

The capsules according to the invention were compared with capsules of the prior art (1 polymer layer and 2 polymer layers) with regard to their stability and the adhesive properties. The comparison was made as follows: The samples were diluted 1:10 with demineralized water and then placed in a measuring cell. The measurement method was set depending on the respective capsule sizes (Smoluchowski: capsules / particles> 100 nm; Hückel: particles <100 nm). The temperature was then set to 25 ° C. and 3 measuring cycles of 10 measurements were carried out. In the end, the mean was formed from the values.

The results are shown in Table 2:

Table 2: Comparison of microcapsules with regard to zeta potential

Table 2 clearly shows that a capsule according to the invention consisting of three polymer layers has a more positive zeta potential than the capsule of the prior art. "Zeta potential" generally means the electrostatic potential that is generated by electrically charged objects in solution. A detailed discussion of the theoretical basis and the practical relevance of the zeta potential can be found, for example, in "Zeta Potential in Colloid Sciences" (Robert J. Hunter; Academic Press, London 1981, 1988). Its value is a suitable measure of the object's ability to produce electrostatic interactions with other objects in the solution, such as surfactants, polyelectrolytes and surfaces.

Table 2 thus clearly shows that a 3-layer structure of the capsule wall thus reduces the surface charge of the capsule, which results in significantly better adhesion, for example to cotton fabric.

Table 3 illustrates the relationship between the thickness of the capsule wall and the number of different polymer layers and the diffusion stability. It is very clearly shown here that the microcapsules according to the invention are significantly more stable with respect to diffusion over time. On the one hand, as already mentioned above, this is due to the at least three-layer capsule wall according to the invention. The capsules consisting of 1 layer and 2 layers are capsules of the prior art. The capsules consisting of 3 layers are capsules according to the invention. All capsules in Table 3 are composed according to Table 2. Over a period of 12 weeks, each measured how much residual perfume oil (as a percentage) remained in the capsule. The more stable the capsule, the more perfume oil must be in the capsule. The capsules were stored in fabric softener at 45 ° C. Likewise, the capsules of the prior art and the capsules according to the invention were increasingly reduced in terms of their shell (proportion of wall [%]). It can thus be clearly seen that the capsules according to the invention, which contain both resorcinol and phloroglucin, have significantly improved stability over a long period of time despite the thinner shell or capsule wall. Table 3: Stability [%] at 45 ° C in fabric softener

Table 4 shows a comparison of the fragrance intensity on cotton fabric after treatment with a fabric softener. The results reflect the function of the various capsules of the prior art and the capsules according to the invention, before and after friction. The different cotton rags were tested by 40 trained panelists. A scale of 1-9 was used, 1 corresponding to no fragrance and 9 corresponding to a very strong fragrance. Table 5 also illustrates this comparison, but after the capsules have been stored for 4 weeks at 40 ° C. Here too it can clearly be seen that the microcapsules according to the invention have the highest fragrance intensity, both before and after rubbing. This illustrates that the microcapsules according to the invention have a high diffusion density, but at the same time have a slightly fragile capsule wall, in order to ensure sufficient release of the encapsulated active ingredient. This makes it clear that the use of free, non-encapsulated perfume oil is not necessary. Nevertheless, the capsules according to the invention are stable enough to ensure that not all of the fragrance is released. Also one Storage stability at elevated temperature is ensured by the capsules according to the invention.

Table 4: Sensor technology of cotton cloth after treatment with fabric softener 40 panellists fresh

Table 5: Sensor system after 4 weeks at 40 ° C.

Furthermore, 0.2% (w / w) of the microcapsule slurry according to the invention and microcapsule slurry from the prior art were diluted in a commercial fabric softener base and stored at 40 ° C. for 4 weeks. Various cloths (2 kg) were then washed in a European washing machine with 30 g of the fabric softener (once with the prior art capsules, once with capsules according to the invention) using the “Express 20” program at 900 rpm. The samples were dried overnight and before and after rubbing by an expert panel (12-15 panelists) The expert panel assessed the intensity of the samples on a scale of 1-9 (l = odorless; 9 = very strong odor) in different orders evaluated (double sample, blind) and the values averaged, Table 6 and Fig. 2 illustrate the results Table 6: Sensor technology after 4 weeks at 40 ° C

Table 6 and FIG. 2 clearly show an improvement over the prior art with regard to the sensory properties of the microcapsules. These results suggest that the capsules are very stable in storage due to the at least three polymer layers, but allow the encapsulated active ingredient, in particular a perfume oil, to be released due to low mechanical stress, such as rubbing.

Claims

PATENT CLAIMS 1. Microcapsules comprising (a) a core containing at least one active ingredient, and (b) a capsule wall, the capsule wall consisting of at least three polymer layers and at least one of the polymer layers consisting of a first phenolic resin, the first phenolic resin comprising 3 to 50% by weight of groups, which are derived from at least one aromatic polyol and at least one further of the polymer layers consists of a second phenolic resin, the second phenolic resin 3 to 50% by weight Includes groups derived from at least one triphenol. 2. Microcapsules according to claim 1, wherein the at least three polymer layers have an alternating structure, wherein a polymer layer which consists of a phenolic resin is separated in each case by a polymer layer which consists of an aminoplast resin. 3. Microcapsules according to at least one of the preceding claims, wherein the aromatic polyol groupings are derived from resorcinol. 4. Microcapsules according to at least one of the preceding claims, wherein the triphenol groups are derived from phloroglucin. 5. Microcapsules according to at least one of the preceding claims, the proportion of capsule wall based on the slurry being 0.3 to 3% by weight. 6. A method for producing microcapsules according to claim 1, comprising the following steps: (a) provision of a first aqueous preparation comprising at least one aldehyde or at least one polyamine precondensate; (b) providing an oil phase containing the active ingredient to be encapsulated and at least one aromatic polyol; (c) mixing the aqueous phase with the oil phase in the presence of at least one emulsifier and / or stabilizer to form an emulsion; (d) starting the polymerization; (e) adding at least one polyamine or a polyamine precondensate; (f) resting the mixture at 40 to 70 ° C for 40 to 80 minutes; (g) adding at least one triphenol; (h) adding at least one aldehyde or at least one polyamine precondensate; (i) resting the mixture at 40 to 70 ° C for 40 to 80 minutes; (j) crosslinking and hardening the microcapsules obtained in step (f) and, if appropriate (k) separating and drying the microcapsules from the dispersion. 7. The method according to claim 6, wherein after step (c) there is a superposition of the reaction with CO 2. 8. The method of claim 7, wherein the superposition of the reaction with CO 2 at least reduces the discoloration of the microcapsules caused by aromatic polyols. 9. The method according to at least one of claims 6 to 8, wherein one uses aldehydes and / or pre-condensates which are selected from the group which is formed from optionally alkylated mono- and polymethylol-urea or mono- and polymethylol-melamine pre-condensates , partially methylated mono- and polymethylol-l, 3,5-triamino-2,4,6-triazine precondensates, mono- and Polyalkylolbenzoguanamine and mono- and polyalkylolglycuril precondensates, dialdehydes, formaldehyde and mixtures thereof. 10. The method according to at least one of claims 6 to 9, wherein a perfume oil is used as the active ingredient to be encapsulated. 11. The method according to at least one of claims 6 to 10, wherein immediately after step (i) the mixture is heated to 80 ° C to 90 ° C to form the outer polymer layer. 12. The method according to at least one of claims 6 to 11, wherein phloroglucinol is added as the triphenol. 13. The method according to at least one of claims 6 to 12, wherein the start of the polymerization in step (d) by lowering the pH to a value of 3 to 5 by adding formic acid or a mixture of formic acid, citric acid and ascorbic acid to block a color reaction of the aromatic polyol. 14. The method according to any one of claims 7 to 13, wherein the addition of at least one aromatic polyol in step (b) and the addition of at least one triphenol in step (f) enables the formation of thin capsule walls. 15. Washing and cleaning agents, cosmetic preparations or perfume compositions containing microcapsules according to at least one of the Claims 1 to 5 or obtainable by the process according to at least one of claims 6 to 14.