GB2490098A

GB2490098A - Air freshener device comprising microcapsules

Info

Publication number: GB2490098A
Application number: GB1105881.5A
Authority: GB
Inventors: Philippe Blondeau
Original assignee: Givaudan SA
Current assignee: Givaudan SA
Priority date: 2011-04-07
Filing date: 2011-04-07
Publication date: 2012-10-24
Also published as: GB201105881D0

Abstract

An air freshener (1, Fig. 1) comprises an unit having two lamellae 2, 3 each having two surfaces and joined with one surface of one lamella opposing a surface of the other lamella. Direct contact between the opposing surfaces is prevented by the presence between the lamellae of a plurality of fragrance-containing rupturable microcapsules 4. The device further comprises a rupture element 5 mounted on the device and adapted to move in the plane of the lamellae, simultaneously applying rupturing force to a desired portion of microcapsules. A method is also claimed, wherein the rupture element is moved to an extent which is sufficient to provide a desired air freshening effect. The device is of particular use in motor vehicles. Preferably, the lamellae are thin layers of paper, cardboard, fabrics, plastics or metal foils. The device may also include surface markings (6, Fig. 1) which indicate an extent to which the rupture element can be moved to emit a sufficient fragrance for a particular time period.

Description

AIR FRESHENER

This disclosure relates to air fresheners, particular air fresheners for use in motor vehicles, Air fresheners have been used in motor vehicles for some time. They serve to impart a fresh odour to an environment that is often left completely closed in warm weather and that otherwise would have a stale or even an unpleasant odour in an older vehicle or the undesirable "new car" smell in a more recent vehicle. Expensive vehicles often have specialised fragrance dispensers with a number of fragrances, which are released according to a program, but for most users, more simple (and much cheaper) alternatives are sought.

While there are many types that are either electrically driven, or that hook into a vehicle's ventilation outlets, a very popular type remains a shaped piece of planar material, such as cardboard, impregnated with fragrance and hung from a suitable place in a vehicle, such as a rear-view mirror. When removed from its wrapping, this device emits fragrance until it is exhausted. It can then be simply replaced by another one, with the same or a different fragrance. The material may be made in any desired shape and colour (it may, for example, comprise particular designs and promotional or commercial material, and be a useful promotional give-away), and the devices are cheap and generally effective, which cxplains their continued popularity.

However, such air fresheners do have certain disadvantages. One of these is the unavoidable change in emitted fragrance intensity. More fragrance will come off at the beginning, and this will tail off as the device becomes older, in the end leading to ineffectiveness. It also has the problem that the odour at one end of the device's life can be overwhelming and non-perceptible at the other. This problem is exacerbated by a hot vehicle interior, which causes the fragrance to be emitted at an even greater rate, thus shortening its useful life even more.

It has now been found that it is possible to provide a simple, inexpensive device that suffers less from these problems. There is therefore provided an air freshener device, comprising a unit, which is comprised of two Iamellae each having two surfaces and joined with one surface of one lamella opposing a surface of the other lamella, direct contact between the opposing surfaces being prevented by the presence between the lamellac of a plurality of fragrance-containing rupturable micro capsules, the device additionally comprising a rupture element mounted on the device and adapted to move in the plane of the lamellae, simultaneously applying rupturing force to a desired portion of microcapsules.

There is additionally provided a method of freshening air in an enclosed space, comprising the provision in that space of a device comprising a unit, which is comprised of two lamellae each having two surfaces and joined with one surface of one lamella opposing a surface of the other lamella, direct contact between the opposing surfaces being prevented by the presence between the lamellae of a plurality of fragrance-containing rupturable microcapsules, and a rupture element mounted on the device and adapted to move in the plane of the lamellae, simultaneously applying rupturing force to a desired portion of microcapsules, and moving the rupture element to an extent sufficient to provide a desired air freshening effect.

By "lamellae" is meant thin plates or layers of material, which define a surface whose linear dimensions are considerably more than its thickness. Provided that the material is suitable for the particular function, the material and the dimensions are not narrowly critical, and the skilled person can readily select a suitable material. Examples include paper, cardboard, fabrics, plastics and metal foils. It is not necessary that the lamellae be identical, and it is possible, for example, that one be a decorative shape, for example, the shape of a flower, and the other a rectangular strip. The lamellae are joined so that each presents an opposing surface to the other, separated over most of the opposing surface area only by the plurality of micro capsules between them. Joining may be by any convenient means, for example, welding, adhesive, mechanical means such as staples, nuts and bolts, rivets, wire or thread, and the like.

Between the opposing surfaces is a plurality of fragrance-containing micro capsules, These are adhered to one or both opposing surfaces by any convenient means, such as adhesive or being dispersed in a film-former, which is then applied to at least one opposing surface. The nature of the capsule wall material themselves is not narrowly critical, provided that it is suitable for the encapsulation of fragrance compositions, and that the capsules are rupturable under the pressure to be applied. In general, this means that they should have an element of rigidity, typically provided either by making them from am material that is inherently brittle, or by causing the necessary brittleness by a suitable degree of crosslinking. Particular examples ofrupturable capsules are crosslinked melamine-formaldehyde resin or crosslinked gelatine capsules. Such capsules are well known to the art and are to be found in many applications where rupture is required. Typical examples may be found in, for example) US Patent 4407231 and PCT published applications WO 2006/056096, WO 2010/049235 and WO 2010/049237.

The nature of the fragrance is determined entirely by hedonic considerations. A great many fragrance materials and fragrance compositions are known to the air freshener art, and any of these may be used.

A further essential element of the device is a rupture element. This element ruptures the capsules by compressing the lamellae together with a force sufficient to rupture them. The movement of rupture is in the plane of the lamellae, that is, the rupture element is caused to move across the surface, rupturing those capsules in its immediate vicinity. The nature of the rupture element depends on the nature of the device. For example, if the lamellae comprise two elongate strips of material, the rupture element may have the form ofa rectangular member having a slot through which the lamellae can pass, the slot being dimensioned so that passage through the slot causes rupture of the microcapsules at that part of the lamellae passing through. Alternatively, one lamella may be rigid and the other flexible, both being circular and the rupture element being a radial member, pivoted at the centre of the circle and adapted to rupture the niicrocapsules in its path as it is turned. The skilled person will readily be able to envisage many variants of this, all lying within the skillof the art.

The device hereinabove described has numerous advantages. It is simple and inexpensive to construct. It can be given an attractive shape or appearance. Most importantly, it is substantially inirnune to the problems suffered by similar devices. For example, in a hot vehicle interior, the capsules will retain substantially all oftheir fragrancc, so the device will have a long lifetime. In addition, the user can adjust the quantity of fragrance in the atmosphere, simply by moving the rupture element to the desired extent. There is therefore no more problem of too much or too little fragrance in the atmosphere, and the individual can adjust to suit personal taste.

The device is now fhrther described with reference to the accompanying drawings, which S describe a particular embodiment, and which are not intended to be in any way limiting.

Figure 1 is a schematic front elevational view of a device.

Figure 2 is a schematic cross-section in a plane perpendicular to the page of the device of Figure 1.

A fragrance emitting device, generally indicated as 1, comprises two strips of paper 2, 3, placed facing each other and adhered at theft outer edges. Between the strips is a layer of fragrance-containing microcapsules 4. The walls of these microcapsules are of crosslinked melamine-formaldehyde resin, the degree of crosslinldng being such that they can be fractured. The device comprises a rupture element 5. This is made of stiff plastics material, and is slidably mounted on the joined strips by means of a slot through which the joined strips can pass. The dimensions of this slot are such that sliding of the rupture element down the strip causes the strips to be compressed together and this causes the capsules at the slot to rupture, thus releasing fragrance.

The strip additionally carries on its surface markings 6. These indicate an extent to which the rupture element can be moved to give what is normally regarded as sufficient fragrance for a particular time period, for example, a week.

Thus, in operation, a device is positioned appropriately, for example, by hanging in a suitable position in a motor vehicle. The rupture element 5 is them moved downwards by an appropriate amount, for example, to the first surface marking (or further or less far, according to conditions and taste). The movement causes the capsules that pass through the rupture element to break, thus releasing their fragrance. When the impact of that fragrance has disappeared, the rupture element may be moved downward a further appropriate distance, to release more fragrance, and so on until the device is exhausted.

Claims

Claims: 1. An air freshener device (1), comprising a unit, which is comprised of two lamellae (2, 3) each having two surfaces and joined with one surface of one lamella opposing a surface of the other lamella, direct contact between the opposing surfaces being prevented by the presence between the lamellae of a plurality of fragrance-containing rupturable micro capsules (4), the device additionally comprising a rupture element (5) mounted on the device and adapted to move in the plane of the Iamellae, simultaneously applying rupturing force to a desired portion of micro capsules.
2. A method of freshening air in an enclosed space, comprising the provision in that space of a device (1) comprising a unit, which is comprised of two lamellae (2,3) each having two surfaces and joined with one surface of one lamella opposing a surface of the other lamella, direct contact between the opposing surfaces being prevented by the presence between the lamellae of a plurality of fragrance-containing rupturable microcapsules (4), and a rupture element (5) mounted on the device and adapted to move in the plane ofthc lamellae, simultaneously applying rupturing force to a desired portion of microcapsules, and moving the rupture element to an extent sufficient to provide a desired air freshening effect.