FR2685857A1 - Aerosol can containing microcapsules - Google Patents

Abstract

Microcapsule-containing spray can consisting of a combined spray container containing one or more perfumed bases composed of high quality essential oils in solution in alcohol in a concentration in the region of 10 per cent by weight, optionally associated with one or more deodorizing, disinfecting, relaxing or other active ingredients, said perfume bases and active ingredients being fully or partially trapped in microcapsules, and a hydrofluoroalcane type of liquified gaseous propellant. The invention has numerous applications in spray blends, in which the products used have only slight compatibility among themselves. However, it is essentially for use in the perfume industry, especially in diffusion and deodorizing perfumes.

Description

AEROSOL BOMB CONTAINING MICRO-CAPSULES
The present invention relates to an aerosol bomb containing microcapsules.

 It can be applied to numerous fields in which mixtures of products which are not very compatible with each other must be vaporized, but is especially intended for use in perfumery, in particular for room fragrances or deodorants.

There are many systems for diffusing room fragrance, evaporators using wicks or spongy bodies impregnated with a liquid, gels, solidified perfumes, scented candles, mixtures of dried flowers, etc. However the most widespread system currently is the pressurized aerosol which allows to vaporize at the desired moment and at will a liquid product in the ambient air
In the conventional aerosols of air fresheners or the most effective room fragrances, the active product is essentially composed of a perfuming base in alcoholic solution or other solvent. The spraying of this active principle under the action of the propellant gas allows, to perfume the atmosphere, to leave at will micro-droplets of perfume / alcohol mixture, in all places of residence or work, but also the automobile or any other means of public or private transport.

 The desired effect, in addition to perfuming the environment, can also be deodorization, disinfection, purification of the ambient air.

 Aerosols of air fresheners or room fragrances are generally low in perfume base.

They are primarily intended for the deodorization of the air and the perfume which is added, acts simply as approval of use, without really being the first performance expected from the product.

 Most pressurized aerosols for room fragrances are not designed to produce a fine vaporization of a real perfume in alcoholic solution in the atmosphere.

 These are generally: - either simple vaporizers, with pump, without propellant gas, whose vaporization performance in ambient air is notoriously insufficient - or aerosols containing CFCs considered to be dangerous for the atmospheric ozone layer - or flammable liquefied gas aerosols (generally a butane / propane mixture), which are moreover not very compatible with the mixtures of essential oils which necessarily enter into the composition of a quality perfume - either compressed gases (nitrogen or carbon dioxide). Due to their very small volume, the compressed gases require the addition of a volatile solvent in the perfume + alcohol mixture. However, solvents of this type, currently available, are not very compatible with quality perfumes.

 Currently, and awaiting new generations of neutral propellants that are completely respectful of the environment, only aerosols having as propellant a liquefied gas of HFA22 type (hydro fluoro alkane), with a mixture strongly dosed in perfume in the alcohol for active ingredient, could claim an acceptable perfuming efficiency and sophistication. However, the long-term effect remains uncertain, as well as the possibility of incorporating without difficulty substances with a complementary effect such as deodorant, disinfectant, air purifier, etc.

 The device according to the present invention eliminates all these drawbacks. Indeed, it allows - to use essential oils and perfume bases of very high quality at a very high concentration in alcohol (of the order of 10% by weight) of the active principle - to associate with these perfume bases an odor absorber, disinfectant, or other products capable of ensuring, for example, disinfection, purification, deodorization, or even existing or future principles, having bactericidal, relaxing, invigorating effects, etc.

- spray harmoniously without denaturing the mixture of active ingredients in solution in alcohol, thanks to the pressure obtained, the choice and the proportion of the propellant.

 It is constituted by the combination of a spray container containing, on the one hand, one or more perfume bases composed of high quality essential oils in solution in alcohol at a concentration close to ten percent by weight, possibly associated to one or more active ingredients such as deodorant, disinfectant, relaxant or the like, these perfume bases and active ingredients being totally or partially trapped in microcapsules and, on the other hand, a liquefied propellant of the hydrofluoroalkane type.

 The detailed description below relates to a non-limiting example of one of the embodiments of the subject of the invention.

 The concentration of the perfume, that is to say of the mixture of essential oils, aromatic raw materials, must be sufficiently important so that the active principle vaporized in the atmosphere in fine droplets is deposited in sufficient quantity on fabrics, curtains, seats , carpets, etc., but also on smooth and cold surfaces due to temperature difference. To obtain real effectiveness, the proportion of these perfuming bases must be of the order of 10% by weight of the solution.

 Combinations, in alcohol in particular, which is the medium where their development takes place under the best conditions, noble perfume bases with other active ingredients often poses problems of cohabitation, and undesirable effects or reactions in the weather.

 The encapsulation of these active ingredients allows them to be released at the appropriate time, including odor absorber systems, which are particularly delicate to incorporate into aerosol formulas.

 The active ingredients, complementary to the perfume, as well as the perfume (perfuming base) itself will be enhanced by their imprisonment in microcapsules, for all or part of them.

 Micro-encapsulation is a technique which allows liquid or solid substances to be trapped in sealed microcapsules. Protected by their capsules, the active ingredients can be incorporated into the liquid phase of the aerosol, in order to isolate them from other aggressive products, which makes it possible to stabilize complex formulas.

 Thus we can perfectly combine several functions so far imperfectly compatible, and in particular perfume and deodorant.

 More particularly, the microcapsules will be used to trap a substantial portion of the perfume base. Imprisoned, this perfuming base part will be released over time with a delayed effect (hitherto very difficult to obtain), either by the regulated degradation in time of the envelope of the microcapsule, or by mechanical crushing, for example by walking on a carpet on which the encapsulated perfume has been previously vaporized.

 The container containing the aerosol can be glass, metal or any other material. The liquefied propellant retained, a hydro fluoro alkane type HFA22, which is currently one of the best suited to ecological requirements, provides the desired non-wetting vaporization without the addition of solvent.

 The perfume bases will always be exclusively dissolved in perfume alcohol for around 85% by volume of the active product, in order to obtain a final product as noble as body perfumes, with all their usual qualities. It can therefore be used without damage towards fragile surfaces such as curtains, upholstery, furniture, etc. without more consequence than the body scent on the skin or clothing.

 Thus, over use and at the whim of each, the perfume dispensed in micro-droplets will be deposited in places of accommodation, offices, vehicles, etc. to install a quality atmosphere, and moreover micro-encapsulation of some of these active ingredients and perfumes will release them with a delayed effect, therefore with a prolonged action.

 The positioning of the various constituent elements gives the object of the invention a maximum of useful effects which had not, to date, been obtained by similar devices.

Claims (4)

CLAIMS characterized by the combination of a spray container containing, on the one hand, one or more perfume bases composed of high quality essential oils possibly associated with one or more active principles such as deodorant, disinfectant, relaxant or other, these bases fragrances and active ingredients being totally or partially trapped in microcapsules and, on the other hand, a non-flammable, non-wetting, liquefied propellant gas without any solvent supply.  1 ". Aerosol bomb containing microcapsules, which can be used in all cases or mixtures of products that are not very compatible with each other must be sprayed, but above all intended to be used in perfumery, in particular for home fragrances or deodorants ,  2 ". Device according to claim 1, characterized in that the fragrance base (s) are dissolved in perfume alcohol at a concentration close to ten percent by weight.  3. Device according to any one of the preceding claims, characterized in that the non-flammable liquefied propellant is a hydrofluoroalkane of the HFA22 type.  4. Device according to any one of the preceding claims, characterized in that the microcapsules used are determined in such a way that part of the fragrance base (s) and of the active ingredients is released with a delayed effect, or by controlled degradation over time of the envelope of said microcapsules, or by mechanical crushing.