CA2250227A1 - Substrate for the controlled release of volatile substances - Google Patents

Abstract

The description relates to a substrate for the controlled release of volatile substances which can be applied to the substrate in metered quantities, in which the substrate is flat, at least one of its surfaces has one or more recesses (2) to accept and store the volatile substances, where the ratio of area to volume of the substrate is at least 1 x 102 m-1, and the substrate consists of a material which is chemically inert to the volatile substances and/or their solvents. The substrate may take the form of at least one base (1) with the largest possible area. The recesses (2) may take the form at least partly of apertures (2) where the ratio of the surface to the volume of the substrate may be at most 500 x 102 m-1 and the substrate may take the form of a gauze, a fabric, a grid, a net or a sieve. Alternatively, the recesses or apertures (2) may be in the form of grooves of any width.

Description

CA 022~0227 1998-09-28 SUBSTRATE BODIES FOR THE CONTROLLED
RELEASE OF VOLATILE SUBSTANCES

The invention relates to a substrate body for the controlled release of volatile substances, where these substances are employed for the disinfection ordeodorization of rooms or for similar purposes, which generally serve for freshening or improving the air in a room.
The dispensers of aromatic or active substances, which, depending upon their functional mode, are classified according to the so-called "Slow-Release" system or the so-called "Controlled-Release" systems, and which, essentially, are based on the controlled release of aromatic or active substances by utilization of different physical or chemical properties, are currently employed not only for domestic use, and here particularly for sanitary purposes or in the interior of vehicles, but find in growing measure, also wide application in the industry as well as agriculture and forestry. By storage and release of volatile substances with disinfecting action, they serve, for example, for extermination of vermin. Concurrently, they are employed for storage and release of volatile substances with deodorizing function, which results in freshening or improving the air in the room.
Substrate materials employed up to now have proven themselves of disadvantage in that normally the stored substances are released too quickly or too slowly. In a disseminated modification, the aromatic or active substance is placed, for example, in a plastic enclosure, which is closed by means of a cellulose membrane.
Said membrane has a defined pore structure so that substance release is difficult to control. With fluctuating air movements, the membrane can dry out quickly, replenishment of stored substance then stagnates. An aged membrane, moreover, has an unwelcome selective effect, so that the entire aromatic or active substance range is no longer released, i.e. over time there occurs a change in the composition of the CA 022~0227 1998-09-28 aromatic or active substances. A simple possibility for storage and release of aromatic or active substances consists in the utilization of porous bodies, in which the aromatic or active substances is located in the pores of a porous body and is evaporated from these pores.
Substrate bodies made of ceramic have a low pore volume of only up to 40% and only a low percentage of open pores. The substances to be evaporated canmainly be stored here on the outer surface, so that only few substrate quantities can be made available per unit of volume. Also, the minerals which are unavoidably trapped in the ceramics may lead to selective fixation of aromatic substances.
The German Patent Specification DE 4417 739 describes in similar context the utilization of a porous body consisting of open-pored sintered glass for storage and controlled release of evaporable substances. The body preferably has a pore volume of 30% to 85% and an average pore size of 10 ,um to 350 ~m.
For sustained and long-term effect of "slow release" systems, in which a unit releasing aromatic or active substances is constantly supplied with volatile substance, it is of great impo, lance that the evaporation (=transition occurring below the boiling point of a substance from liquid to gaseous aggregate state) or the sublimation (=direct transition of a substance from solid into gaseous aggregate state without taking on the normally interpositioned liquid aggregate state) releases the aromatic or active substances, without interruption, over a longer period of time, in other words, depending upon the application field, no less than several hours, as uniformly as possible in constant concentration and in constant composition. However, targeted control of the release of aromatic or active substances is hereby difficult, in some instances even altogether impossible.
Accordingly, "Slow-Release" systems have various drawbacks and insufficiencies. They are generally slow to react, i.e., in closed rooms, based on the slow release of the active substances, some time elapses before the desired concentration of active substances is reached. This, however, is clearly in contrast to the objective, i.e., for example, to immediately perceive the pleasant smell following application in residential or commercial premises. With application of insecticides in closed rooms as well, it is desirable to obtain the necessary concentration as quickly as possible so that no more than absolutely necessary of active substance will have to be CA 022~0227 1998-09-28 employed. After that, concentration of active substances shall be maintained over a given time period.
In general, that the USiow-Release'' systems have a certain inefficiency, since they continuously evaporale the active suL,slances, i.e., even at times when there is no need in this regard. In addition, the USlow Release" Systems fail to take into consideration the constantly growing environmental concerns, since "Slow-Release"
Systems require high packaging outlay and are not refillable in most instances.
In contrast to the "Slow-Release" Systems, with utilization of metering devices such as sprays, atomizer systems, drip-bottles, or perhaps even brush-applicator bottles, a portion of the aromatic or active substance can be released immediately when needed by application on one or several surfaces of the substrate, so that metering devices are generally chara~;teri~ed by an immediate effect, which, until now, lasted only for a relatively brief period of time.
For purposes of continuous release of aromatic or active substances a frequently employed technique consists of releasing from an atomizer a given quantity of an aromatic or active substance, and spraying of same into a substrate material, whereby, according to the state of the art, recommended materials consist of cellulose cardboard, felt or fleece.
These materials are usually employed in "Slow-Release" Systems and absorb aromatic or active substances almost totally.
The German Patent Disclosure Document DE 25 40 075 discloses an aerosol can with a substrate, arranged at least in part in the path of the issuing spray beam, made of absorbent, permeable material, preferably paper or pasteboard material.
Even though the size of the surface of the substrate, which is designed as a protective casing or in form of a protective cover of the aerosol can, and the size of the passage opening and the perforations arranged in the protected cover are adjustable, the aerosol can, primarily at the moment of activation, develops a brief, but relatively strong action.
The ensuing action over a longer period of time naturally takes place with significantly reduced intensity, since the outgoing aromatic or active substance is bonded or consumed rather quickly. During and shortly after the spraying, ample aerosol or active substance is present in the surrounding air and, consequently, a strong effect, but that disappears rather quickly inasmuch as the aromatic or active substance escapes with CA 022~0227 1998-09-28 ventilation, so that afterwards the active sources which pollute the air, predominate.
In the German Disclosure Specification DE 23 31 891 an operating cap for aerosol container is suggested, which, if it affixed to the aerosol container instead of the normal removable cap, permits simple operation of the fluid release valve for atomizing the fluid, whereby the hand of the user is protected from contact with the fluid and whereby the atomizing occurs in such manner that a part of the atomized fluid is sprayed freely into the air, while the rest of the fluid impregnates an absorbent material, from which it can evaporate, in order to achieve both immediate as well as sustained support for chemicals in the fluid. The operating cap for aerosol containers disclosed in DE 23 31 981 is hereby specifically intended for use with aerosol containers that have a valve which releases the liquid contents in axial direction and is operated by means of finger pressure.
From the German Disclosure Document DE 37 06 256, a release device is known for volatile substances, specifically for air fresheners, comprising a pressure container which contains the releasable substances combined with a propellant.
Activation of the release valve of the container takes place via a hollow push button, which has at least one perforated wall area and which cooperates in longitudinaldirection with the discharge head, which is connected with the movable part of the release valve. At least one absorbent element is arranged in the push button, which is impregnated with substances which are being released from the pressure container via at least one exit opening present in the discharge head, and which are being flung inside the push button against a deflector plate and then dropped onto the absorbent element.
The aforementioned specifications DE 25 40 075, DE 23 31 981 and DE
37 06 256 have in common that respectively from one atomizer a given quantity ofaromatic or active substance is released and sprayed into a substrate. Frequently employed substrates in this connection are suggested such as bodies made totally of cellulose fibers, specifically cellulose felts, cellulose cardboards or cellulose fleeces.
These materials, which usually are employed for the initially described "Slow-Release"
Systems, have no defined pore structure and reduce via their fiber structures the action of the capillary forces. The numerous cellulose hydroxyl groups, due to their interaction with polar groups of the aromatic or active substances and with water molecules, CA 022~0227 1998-09-28 facilitate that already upon storage there may take place an unintentional strong fixation of the active and aromatic substances and that upon release of active substance,unwelcome chromatography effects may occur, whereby, with respect to most of theactive and aromatic substances or substance mixtures, medium to heavy impairments are caused relative to ambient effect, for example, shifts in the aromatic effect compared with the non-absorbent original material.
Another drawback of the cellulose bodies lies in their swelling capability.
With higher air humidity, the cellulose body may break open in layers, whereby the then following disproportionate entry of air shortens the time of effectiveness and modifies the desired concentration of active substance in the ambient air. Thus, there may be deformations and discolorations with respect to the cellulose bodies, which has a detrimental effect upon the aesthetic impression and which, naturally also detrimentally affects the ability to sell products having such substrates.
What needs to be remembered is that the substrate materials from cellulose fibers which have been used until now in the "slow-release" systems with metering arrangements respectively presented in specifications DE 25 40 075, DE 23 31 981 and DE 37 06 256 do not function in the desired fashion, since evaporation of the aromatic or active substances is not controlled in an orderly manner by the suggested substrate materials. The suggested substrate materials inappropriatelyabsorb the active substances and evaporate the same at too low a rate or to a significant degree not at all.
From the German utility model patent DE 93 18 043.8, flat fragrance stones are know, formed of baked clay in the shape of half a peach stone, which have recesses on their surface. These fragrance stones are dipped in water and sprinkled with aromatic oils, as a result of which they exude fragrance for days.
The Specification GB 286 862 discloses a volatile, deodorizing or disinfecting block, which is fitted on the outside with surface recesses, such as grooves, for example, so that the surface is significantly enlarged in proportion to the volume. It is, however, not clearly apparent from Specification GB 286 862 that the volatile substances can be applied to the substrate in dosable manner, inasmuch as a disinfecting block of solid naphthals is described, for example. Furthermore, it is not clearly evident from Specification GB 286 862 that the substrate material needs to be CA 022~0227 1998-09-28 chemically inert.
Finally, it should be noted that neither the German utility model patent DE
93 18 043.8 nor the specification GB 286 862 provides any data regarding the ratio of surface relative to the volume of the substrate body.
Based on the above described inadequacies, it is the object of the present invention to make available a substrate for metering arrangements such as sprays, atomizing systems, drip bottles, or perhaps, brush-applicator bottles, specifically for use in rooms, for acceptance storage and controlled release of portions of volatile substances (aromatic or active substances) so that, on the one side, immediate aromatic effect with satisfactory, uniform dosing capability is assured, and that this, on the other side, is made possible for an extended period of time. Accordingly, the present invention is aimed at a substrate which will accept only when needed, and in one portion, to be applied aromatic or active substances without absorbing them.Depending upon the temperature, the combination of active substances is hereby to be controlled and completely released by the substrate, at a constantly high rate. In this context, it is another advantage of the invention to provide a substrate which warrants such continuous evaporation or sublimation of the store substances in unchanged composition.
According to the invention, said object is solved with a substrate for controlled release of volatile substances (aromatic or active substances), which are applicable in dosable form on the subsl~dle, in that the substrate has a flat design, that at least one of the surfaces of the substrate has one or several recesses for acceptance and storage of the volatile substances, whereby the ratio of surface to volume of substrate is at least 1 1 02m ', and that the substrate consists of a material which is chemically inert with respect to the volatile substances and/or their solvents.
Thus, a continuous evaporation or sublimation of the stored substances with unchanged composition is guaranteed for a long period of time, as compared with direct application of a dose into the air. The fragrant impression as well as the optical impression of the substrate is retained without suffering any unwelcome modification.
By arranging at least one recess in at least one surface of the substrate, the guarantee is given for instant fragrance effect with concurrent continuous dosing ability over a long period of time in comparison to a direct application of a dose into the CA 022~0227 1998-09-28 air.
According to a beneficial specific embodiment of the present invention, the material of the substrate is organic or inorganic synthetic material, specifically ceramic or glass with a thermal conductivity in the range of at least 10-' m-' K-' to a maximum of 35 10-' m-' K-', whereby the concerned plastic preferably involves polyethylene (PE) with thermal conductivity in the range of 1.2 10' m-' K-' or polypropylene (PP) with a thermal conductivity in the range of 1.2 10' W m~' K-'. This implies that with use of substrate materials having such proportionately low thermal conductivities, additionat measures may be employed for extending the sensory perception. The substances should be hereby applied on the substrate in areas as large as possible, i.e., they should be atomized, sprayed or brushed.
According to an alternative beneficial specific embodiment of the present invention, the material of the substrate is metal or a metal alloy with a thermal conductivity in the range of at least 10' W m-' K-' to a maximum of 40 10' W m~' K-', whereby the metal alloy preferably involves stainless steel with a thermal conductivity in the range of 1.5 10' W m-' K-'. Accordingly, one derives in surprisingly simple but still definitely effective manner benefit from the fact that a given volume of volatile substances at room temperature can be perceived for a longer period of time, the higher the thermal conductivity of the material of which the substrate is. With reference to the present invention, this means that the thermal conductivity of the carrier material should be the higher the more volatile the substances, in order to achieve in this manner an extension of the sensory perception of fragrance as compared with a direct application into the air.
A particularly appropriate refinement is the substrate according to the invention in form of at least one substrate plate having the largest possible surface. In this context, a form of embodiment of the present invention is for example conceivable in which the substrate is designed in the shape of two or more substrate plates which are arranged parallel toward each other. Alternatively or supplementary thereto, the substrate may also be designed in the form of two or more substrate plates, which are arranged toward each other in lateral off-set and/or angular off-set. In each of the aforementioned instances it has been shown appropriate that the two or more substrates are connected with each other by connection means.

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CA 022~0227 1998-09-28 According to a particularly beneficial specific embodiment of the present invention, the substrate may be designed in curved form, specifically in form of a cylinder wall, a conical casing or a spherical shell.
Preferred embodiments of the substrate according to the invention include that the substrate has a surface in the range of at least 2 cm2 to maximum 500 cm2 and a thickness in the range of at least 0.1 mm to maximum 2 mm.
According to a particularly inventive refinement of the present substrate, the recesses are designed, at least in part, as pe, rora~ions, whereby the ratio of surface to volume of the substrate is approximately maximal 500 1 o2 m~'.
According to another beneficial embodiment of the present invention, the recesses or perforations are arranged at regular intervals. If the recesses or perforations are hereby designed in such manner that the substrate is in form of a gauze, a tissue, a grid or a screen, or if the recesses or perforations are designed in form of grooves with random widths, then additional extension of the sensory perception of fragrance is achieved.
If the substrate is designed in form of at least one carrier plate having the largest possible surface, then with respect to a particularly preferred refinement of the substrate according to the invention, the depth of the recesses or perforations in the substrate is equal to the maximal thickness of the substrate. Independent thereof, the diameter of the recesses or perforations beneficially ranges between no less than 0.2 mm to maximal 1 mm, while the mid-point distance of adjacent recesses or perforations lies in the range of no less than 0.2 mm to maximal 60 mm.
If the recesses or perforations according to the above-mentioned dimensional specifications are filled completely with the volatile substances (aromatic or active substances) adequate provision exists for desirable convection with respect to the present field of application for the substrate according to the invention, whereby the volatile substances are evaporable in all directions.
As is already apparent from the preceding, for successful employment of the substrate according to the invention, its physical structure is of particular importance. For this reason, the surface areas of the substrate which have recesses or perforations occupy maximal 60% of the entire substrate surface.
An extension of the sensory perception of fragrances is also achieved by CA 022~0227 1998-09-28 coating the substrate - at least in sections or spots - with at least one medium which appropriately increases the adhesion of the volatile substances. The medium is hereby preferably light-and/or oxidation-resistant and, beneficially, odor neutral. The medium may for example, involve a fixing agent which is, for example, applied to the substrate via atomizer or it may involve an oil.
In actual use, when the volatile substances are applied by a metering arrangement onto the substrate, the substrate appropriately is at a distance of maximal 20 cm from the metering arrangement.
In the following, the invention is explained in more detail based on the Figs. 1 to 13 schematically representing exemplary embodiments, depicted partially enlarged:
Fig. 1 shows a schematic bird's eye view of a first specific embodiment of a substrate according to the invention for controlled release of volatile substances;
Fig. 2 shows a schematic bird's eye view of a second specific embodiment of a substrate according to the invention for controlled release of volatile substances;
Fig. 3 shows a schematic bird's eye view of a third specific embodiment of a substrate according to the invention for controlled release of volatile substances;
Fig. 4 shows an enlarged segment of the schematic bird's eye view depicted in Fig. 3 of the third specific embodiment of a substrate according to the invention;
Fig. 5 shows a lateral sectional view of the enlarged section of the schematic bird's eye view depicted in Fig. 4 of the third specific embodiment of a substrate according to the invention, along sectional line S4-S4 from Fig. 4;
Fig. 6 shows an enlarged section of a schematic bird's eye view of a fourth specific embodiment of a substrate according to the invention for controlled release of volatile substances;
Fig. 7 shows an enlarged section of a schematic bird's eye view of a fifth specific embodiment of a substrate according to the invention for controlled release of volatile substances;
Fig. 8 shows an enlarged section of a schematic bird's eye view of a sixth specific embodiment of a substrate according to the invention for controlled release of volatile substances;

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CA 022~0227 1998-09-28 Fig. 9 shows an enlarged section of a schematic bird's eye view of a seventh specific embodiment of a substrate according to the invention for controlled release of volatile substances;
Fig. 10 shows a schematic view of an eighth specific embodiment of a substrate according to the invention for controlled release of volatile substances;
Fig. 11 shows a schematic view of a ninth specific embodiment of a substrate according to the invention for controlled release of volatile substances;
Fig. 12 shows a schematic bird's eye view of a tenth specific embodiment of a substrate according to the invention for controlled release of volatile substances;
and Fig. 13 shows a room air freshener with an eleventh specific embodiment of a substrate according to the invention for controlled release of volatile substances.
The schematic views in Figures 1 to 12 represent ten specific embodiments of a substrate according to the invention for acceptance, storage and controlled release of volatile substances (aromatic or active substances), which can be applied, dosably, onto the substrate. The substrate hereby facilitates immediate effect of fragrance, according to the invention, over a longer period of time, with concurrent dosability, which guarantees continuous evaporation or sublimation of the storedsubstances in unchanged composition for a long period of time, as compared with direct application of a dose into the air. The fragrant impression thus remains for a long time on the substrate without experiencing any undesirable change. It should be noted here that additional extension of the sensory perception of rragrance is also attained by spot-wise application onto the substrate of at least one medium, which increases the adhesion of the volatile substances. The medium is hereby resistant to light andoxidation and also odor neutral. The medium may for example involve a fixing agent, which is applied for example on the substrate by an atomizer or it may involve oil.
Fixing agent in this context are substances which are capable to bestow increased durability to the fragrance of the volatile substances and to decelerate and adapt the evaporation of the individual fragrance components in such manner that the character of the fragrance remains relatively constant during the evaporation time. The fixing agent themselves are hereby mostly not easily volatilized and high-boiling and they can be fragrant or odor-free.

CA 022~0227 1998-09-28 The schematically represented specific embodiments in Fig. 1 to 12 all have in con,mol1 that each of the represented substrates has recesses or perforations 2 for acceptance and storage of the volatile substances. As stated above, for successful employment of the substrate accorcling to the invention, its physical structure is of particular importance. For that reason, the substrates according to the invention depicted in Fig. 1 to 12, have as flat design so that the ratio of surface to volume in these suL)sl,ales amounts to at least 1 1 o2 m-'. Depending upon the concrete design and the number of recesses or perforations 2 for acceptance and storage of volatile substances, the upper limit for the ratio of surface to volume lies at 500 1 o2 m~' for these substrates. The ratio of surface to volume preferably ranges between 5 1 o2 m~' to 100 102 m~'.
In addition, the areas of the surface(s) of the substrate, which have recesses or perforations 2, occupy in Figures 1 to 12 a maximum of 60% of the total surface of the subsl, ate. The substrate has a surface of no less than 2 cm2 to maximal 500 cm2 and a thickness (D) ranging from minimal 0.1 to maximal 2mm.
It is not explicitly evident from Fig. 1 to 12, however, that the substrates according to the invention consist of material which is chemically inert towards the volatile substances and/or their solvents. Said material is, for example, an organic or inorganic synthetic material, specifically ceramic or glass, with thermal conductivity ranging from minimal 10' W m~' K-' to maximal 35 10' W m~' K-', whereby the synthetic material may involve polyethylene (PE) with thermal conductivity in the range of 1.2 10' W m~' K-' or propylene (PP) having a thermal conductivity in the range of 1.2 10' W m~' K-'. As an alternative, the material of the substrate may consist of metal or a metal alloy with thermal conductivity in the range of minimal 10' W m~' K-' to maximal 4010' W m~' K-', whereby the metal alloy may involve stainless steel having a thermal conductivity in the range of 1.5 10' W m~' K-'. Inasmuch as a certain volume of volatile substances at room temperature is perceived longer with higher thermal conductivity of the material of which the substrate is made, that means that in regard to the represented specific embodiments, the thermal conductivity of the substrate should be the higher, the more volatile the substances, in order to obtain in this manner an extension of the sensory perception of fragrance in comparison with a direct application into the air. This implies, on the other hand, that with low thermal .. . . .

CA 022~0227 1998-09-28 conductivity of the substrate, additional measures may be taken for extension of the sensory perception of fragrance. The substances shall be implied in largest possible areas on the substrate, in other words atomized, sprayed or brushed.
In Fig. 1, 2 and 3, the substrate according to the invention is respectively designed in the shape of a substrate plate 1 with outer surface as large as possible.
The recesses or perforations 2 in the substrate plate 1 are respectively designed at regular intervals in the shape of circular holes, whose diameter ~ lies within the range of minimal 0.2 mm to maximal 1 mm, while its mid-point distance A lies in the range of minimal 0.2 mm to maximal 60 mm.
With respect to the first specific embodiment represented in Fig. 1 (RV =
round holes staggered) of a substrate for controlled release of volatile substances, one calculates the percentage portion Ao of open area relative to total surface Ao = 90.7 x ~/A)2 whereas with respect to the represented second or third specific embodiments in Fig. 2 or Fig. 3 (RD = round holes diagonal or RG = round holes straight) of a substrate for controlled release of volatile substances, the percentage-wise portion Ao of open area to total surface amounts to Ao = 78.5 (~)/A)2.
In order to better understand the foregoing characteristic qualtities, Fig.
4 depicts an enlarged section of the schematic bird's eye view onto the third specific embodiment of a substrate according to the invention represented in Fig. 3. Fig. 5 shows a lateral sectional view of the section shown in enlarged format in Fig. 4 of the schematic bird's eye view onto the third specific embodiment of a substrate according to the invention along the sectional line S4-S4 from Fig. 4, whereby in Fig. 5 the depth T of the recesses or the perforations is equal to half the thickness D of the substrate plate 1.
If, for example, polyethylene (PE) is selected as substrate with the respective Figs. 1, 2 an 3 dimensions, with PE having a thermal conductivity in the range of 1.2 10' W m~' K-', then, based on the depicted arrangement of holes, anextension in the sensory fragrance perception is noted from one half hour to nine hours, i.e., by a factor of 18.
In this context it should also be noted that the diameter ~) of the holes arranged in the substrate depends as well upon the type of application of the volatile substance. If application of volatile substances is made, for example, by spray can onto CA 022~0227 1998-09-28 the substrate, the holes should have a diameter ~) of about 0.2mm, while for application with mechanical atomizers hole diameters (3 in the range of approximately 0.6mm will produce convincing results. In each case the upper limit for the hole diameter ~ is defined by the percenlage of droplets passing through. The maximum possible number of clroplels should adhere to the sub~l,dle 1, without forming a coherent film. The holes arranged with dimensioning as specified above should not be completely filled with the volatile substances, so that there is sufficient desired convection with respect to the existing field of application of the substrate according to the invention.
Fig. 4 shows a schematic bird's eye view onto a fourth specific embodiment of a substrate according to the invention for controlled release of volatile substances, wherein irregularly shaped recesses or perforations 2 are arranged at irregular intervals in the substrate plate 1.
In the preceding, mention was made that the recesses or perforations 2 in the substrate plate 1 may also be designed in such manner that the substrate plate 1 has the form of a gauze, a tissue, a grid, a net or a screen. Thus, in the fifth and sixth specific embodiment of a substrate body for controlled release of volatile substances, which are depicted in schematic bird's eye view in Figs. 7 and 8, the recesses or perforations are designed in such fashion that the carrier plate 1 has the shape of a grid with quadratic structure (Fig. 7) or with honeycomb constructions (Fig. 8).
Fig. 9 depicts a schematic bird's eye view of a seventh specific embodiment of a substrate body according to the invention for controlled release of volatile substances, wherein the recesses or perforations 2 are designed in form of grooves, based on the same quadratic recesses of Fig. 7 and the honeycomb shapedperforations of Fig. 8, as a result of which additional extension is obtained of the sensory perception of fragrance.
Fig. 10 depicts a schematic view of an eighth specific embodiment of the substrate body according to the invention for controlled release of volatile substances.
Said substrate body is designed in the form of four substrate plates 1, which are arranged parallel to each other and which are not only interconnected but also stabilized in said position and supported by the connection means 5.
Fig. 12 shows a schematic bird's eye view onto a tenth specific embodiment of a substrate body according to the invention for controlled release of CA 022~0227 1998-09-28 volatile substances. Said substrate body is designed in the shape of two substrate plates 1, represented in Fig. 1, which are arranged relative to each other at angular off-set, and in the depicted embodiment of Fig. 12 at right-angle angular off-set and which are connected with each other by angular connection means 5, but which are stabilized in said position and supported by the connection means 5. It is, of course, self-understood that the angular off-set may be according to any degree from among the different 90~ values.
Fig. 13 depicts a room air freshener with an eleventh specific embodiment of a substrate body according to the invention for controlled release of volatile substances. A container 3 which may, in principle, have any shape is filled with liquid aromatic or active substances, whereby the dosing of the liquid aromatic or active substances is done by means of a dosing device 4, such as an atomizer. In Fig. 13, the substrate plate 1 according to the invention, which is intended for acceptance and evaporation of the portion of active substance, is designed in curved form; it consists of stainless steel, is perforated and arranged concentrically around the dosing device in form of a cylinder wall, whereby during the application of the volatile substances the substrate plate 1, is at a distance of maximal 20 cm from the dosing device 4. It should also be noted here with regard to Fig. 13 that the substrate plate 1 can, of course, also be in the shape of a conical casing or a spherical shell for example.

Example:
In conclusion we are describing an exemplary experiment, during which 0.1 ml of toilet water was applied by spraying via mechanical atomizer onto a suitable selection of aforenamed substrate materials or (for reference purposes) into the air.
The length of fragrance permanency was ascertained in 50 m3 large rooms by different persons, whereby the tests were undertaken at a room temperature of 20~C +/- 1 ~C.
The table below lists, in the left-hand column, the different substrate materials; the right-hand column shows the fragrance permanency (measured in hours), in each case involving a substrate plate 1 in non-perforated stated and in perforated state (see center column):

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Substrate Material Substrate Plate PerforatedLength of Fragrance in Hours Polyethylene (PE) No 3 Yes 20 Steel 1.430 No 7 Yes 33 Alr _, . . . . . .

Claims (30)

1. Substrate body for controlled release of volatile substances, which can be dosably applied onto the substrate body, characterized in that the substrate body has a flat shape, that at least one surface of the substrate body has one or several recesses (2) for acceptance and storage of the volatile substances, whereby the ratio of the surface to volume of the substrate body is maximal 1 ~ 10 2 m-1, and that the substrate body consists of a material which is chemically inert relative to the volatile substances and/or their solvents.

2. Substrate body according to Claim 1, characterized in that the material of the substrate body is of organic or inorganic synthetic material, specifically ceramic or glass, with a thermal conductivity ranging from minimal 10-1 W ~ m-1 K-1 to maximal 35 10-1 W ~ m-1 ~ K-1.

3. Substrate body according to Claim 2, characterized in that the synthetic material involved in Polyethylene (PE) with a thermal conductivity in the range of 1.2 10-1 W ~ m-1 ~ K-1 or polypropylene (PP) with a thermal conductivity in the range of 1.2 10-1 W ~ m-1 ~ K-1.

4. Substrate body according to Claim 1, characterized in that the material of the substrate body is metal or a metal alloy with a thermal conductivity in the range of minimal 10-1 W ~ m-1 ~ K-1 to maximal 40 10-1 W ~ m-1 ~ K-1.

5. Substrate body according to Claim 4, characterized in that the metal alloy involved is stainless steel with a thermal conductivity in the range of 1.5 10-1 W ~ m-1 ~ K-1.

6. Substrate body according to one of Claims 1 to 5, characterized in that the substrate body is designed in the shape of at least one substrate plate (1) having the largest possible surface.

7. Substrate body according to Claim 6, characterized in that the substrate body is designed in the shape of two or more substrate plates (1) which are arranged parallel to each other.

8. Substrate body according to Claim 6 or 7, characterized in that the substrate body is designed in the shape of one or more substrate plates (1) which are arranged toward each other at lateral offset.

9. Substrate body according to one of Claims 6 to 8, characterized in that the substrate body is designed in the shape of one or more substrate plates (1), which are arranged at angular off-set toward each other.

10. Substrate body according to one of Claims 7 to 9, characterized in that the two or more substrate plates (1) are connected with each other by connection means (5).

11. Substrate body according to one of Claims 6 to 10, characterized in that the substrate plate (1) is designed in curved shape.

12. Substrate body according to Claim 11, characterized in that the substrate plate (1) is designed in form of a cylinder wall, a conical casing or a spherical shell.

13. Substrate body according to one of Claims 6 to 12, characterized in that the carrier plate (1) has a surface in the range of minimal 2cm2 to maximal 500 cm2.

14. Substrate body according to one of Claims 6 to 13, characterized in that the substrate plate (1) has a thickness of minimal 0.1 mm to maximal 2 mm.

15. Substrate body according to one of Claims 1 to 14, characterized in that the recesses (2) are designed, at least in part, as perforations (2).

16. Substrate body according to Claim 15, characterized in that the ratio of surface to volume of the substrate body is maximal 500 10-1 m-1.

17. Substrate body according to Claim 15 or 16, characterized in that the recesses or perforations (2) are arranged at regular intervals.

18. Substrate body according to one of Claims 15 or 17, characterized in that the recesses or perforations (2) are designed in such fashion that the substrate body has the shape of gauze, tissue, grid, net or screen.

19. Substrate body according to one of Claims 15 to 18, characterized in that the recesses or perforations (2) are designed in the form of grooves having random width.

20. Substrate body according to Claim 14 and according to one of Claims 15 to 19, characterized in that the depth (T) of the recesses or perforations (2) is maximal equal to the thickness (D) of the substrate plate (1).

21. Substrate body according to one of Claims 15 to 20, characterized in that the diameter (~) of the recesses or the perforations (2) ranges between minimal 0.2 mm to maximal 1 mm.

22. Substrate according to one of Claims 15 to 21, characterized in that the mid-point distance (A) of adjacent recesses or perforations (2) ranges from minimal 0.2 mm to maximal 60 mm.

23. Substrate body according to one of Claims 15 to 22, characterized in that the areas of the surface of the substrate body which have recesses or perforations, occupy maximal 60% of total surface of the substrate body.

24. Substrate body according to one of Claims 1 to 23, characterized in that the substrate body is coated, at least in parts or spots, with at least one medium.

25. Substrate body according to Claim 24, characterized in that the medium increases the adhesion of the volatile substances.

26. Substrate body according to Claim 24 or 25, characterized in that the medium is resistant to light and/or oxidation.

27. Substrate body according to one of Claims 24 to 26, characterized in that the medium is odor neutral.

28. Substrate body according to one of Claims 24 to 27, characterized in that the medium is a fixing agent.

29. Substrate body according to one of Claims 24 to 28, characterized in that the medium is oil.

30. Substrate body according to one of Claims 1 to 29, characterized in that during the application of volatile substances by a dosing device, the substrate body is at a distance of maximal 20 cm away from the dosing device.