WO2009111903A1

WO2009111903A1 - Volatile material emitting device

Info

Publication number: WO2009111903A1
Application number: PCT/CH2009/000093
Authority: WO
Inventors: Colin Litten-Brown; Guy Edward Naish
Original assignee: Givaudan Sa
Priority date: 2008-03-14
Filing date: 2009-03-13
Publication date: 2009-09-17
Also published as: GB0804762D0

Abstract

A device adapted to emit into an atmosphere a volatile material such as a fragrance, the device comprising a source of volatile material adapted to emit the volatile material into the atmosphere, a heat source adapted to enhance the emission, and a source of forced air current adapted to low on the source and convey the material into the atmosphere, characterized in that the device is configured so that the heat source heats the air current prior to blowing on the source.

Description

VOLATILE MATERIAL EMITTING DEVICE

This disclosure relates to a device for controlling the release of volatile material from a dispenser by the use of forced, warmed air.

Devices for dispensing volatile materials, such as fragrances, insecticides and disinfectants into an atmosphere are well known and widely sold and used. The emission source of volatile materials may be selected from a range of possibilities, for example, porous wicks and loaded gels. These may rely on evaporation alone, or the evaporation may be augmented, typically by a forced air current, heating or both, the power being provided by mains electricity, solar cells or batteries. In devices utilizing both forced air current and heating, the heating has been applied to the emission source, for example, by placing a heating element in, near or around a wick.

While this has worked tolerably well, the use of such an arrangement may result in the emission source being unevenly heated, and the forced air current cooling parts of the emission source, making emission less than optimal.

It has now been found that it is possible substantially or even completely to overcome these problems and to provide an enhanced emission of volatile material. There is therefore provided a device adapted to emit into an atmosphere a volatile material, the device comprising a source of volatile material adapted to emit the volatile material into the atmosphere, a heat source adapted to enhance the emission, and a source of forced air current adapted to blow on the source and convey the material into the atmosphere, characterized in that the device is configured so that the heat source heats the air current prior to blowing on the source.

There is also provided a method of providing a volatile material in an atmosphere, comprising the blowing of a forced air current on a source of volatile material, characterized in that the forced air current is heated prior to blowing on the source.

The emission source may be any source capable of providing volatile material in an atmosphere. One typical example is a reservoir of volatile material from which reservoir extends a wick. By "wick" is meant any kind of porous entity capable of absorbing volatile liquid from a reservoir and conveying from the reservoir to a place where it can be emitted into the atmosphere. The wick may be of any convenient form (such as a flat or curved surface or a cylinder) or material (such as cardboard, plastic, or sintered metal or ceramic). The material must naturally be able to withstand attack by the volatile liquid for a desired period.

Another emission source is a gel, that is, a crosslinked polymer, which has been loaded with volatile material, which material can evaporate therefrom. Gels useful for this purpose may be selected from the wide variety of such materials commercially available, for exam- pie, the reaction products of functionalized polymeric components and cross-linking components, the components comprising complementary reactive groups that react to form a three-dimensional gel structure.

Typical examples of suitable functionalized polymers include maleinised polybutadiene and maleinised polyisoprene. Maleinised polybutadienes having a molecular weight of from 5000-20,000 are commercially available, e.g. those sold under the trade name "Lithene" by Revertex Limited. Such polymers containing acid or anhydride or acid chloride groups can be cross-linked with amines or alcohols. Cross-linking agents include, but are not limited to, compounds that contain amine, alcohol or thio functional groups.

Suitable cross-linking agents can also contain a combination of one or more thio, amine and alcohol functional groups, one particular example being polyamines. Suitable poly- amine cross-linking agents include diamines, including polyoxypropylenediamine (such as Jeffamine™ D-400, available from Huntsman Corp., Salt Lake City, Utah) and triethyle- neglycoldiamine (such as Jeffamine XTJ-504), and triamines, such as polyoxypropyl- enetriamine (such as Jeffamine T-403 and XTJ-509).

Another suitable combination of functionalized polymer and cross-linking agent is one in which the functionalized polymer is a modified polyamide, cross-linkable by reaction with a polyisocyanate. A typical polymer of this type is Sylvaclear™ of Arizona Chemicals and a typical polyisocyanate is one of the Desmodur™ range of Bayer Material Science. A further source may be a sublimable material, that is, a material that goes directly from solid state to gaseous state. Typical examples of such materials include adamantane and derivatives thereof, para-dichlorobenzene, 2,4,6-triisopropyl-l,3,5-trioxane, camphor, naphthalene, 1,2,3-trichlorobenzene, 1,4-cyclohexanediol, menthol, acetamide, diphenylethane, hexachloroethane, benzoid acid, benzophenone, benzyl cinnamate, benzyl isoeugenol, benzylidene acetone, cedrol, cinnamic alcohol, coumarin, dimethyl fumarate, hydroquinone dimethyl ether, acetyl isoeugenol, methyl cinnamate, methyl coumarin, napthyl ethyl ether, phthalide and thymol. The sublimable material may be made in any suitable form, such as a cylindrical rod, or in powder form.

The emission source is particularly supplied as a refill, so that the device may be easily replenished when the volatile material is exhausted, or when a different volatile material is desired.

The source of forced air current may be any suitable source, such as a compressed gas or aerosol, but it is typically a fan or blower. These are readily available and widely used, for example for cooling laptop computers. They are obtainable in a variety of sizes, some quite small, so that small and inexpensive devices may be provided.

The heat source may be any suitable heat source. It will typically be electrically heated (in a particular embodiment, by means of the same source of electricity used to power the forced air current) and can be any suitable heat source, such as a resistance that heats when an electrical current is passed through it.

The device is configured so that the air current is heated prior to its arrival at the emission source. This can be arranged in any suitable manner, and the skilled person will readily be able to devise suitable arrangements. For example, a fan or blower can blow air over a heat source and suitable ducting can then lead the heated air current to the emission source and thence into the atmosphere. Alternatively, a fan or blower can be placed between heat source and emission source, and arranged such that the fan or blower sucks air into the device and across the heat source, prior to expelling it towards the emission source. A third further possibility is the location of the fan or blower on the side of the emission source remote from the heat source and arranging for it to draw air over the heat source and then past the emission source, prior to its emission into the atmosphere. The degree to which the air is heated will depend on a number of factors, such as the layout and dimensions of the device, and the natures of the heating element, the volatile material and the emission source. However, again, the skilled person can devise a suitable heating with only routine experimentation.

Other variants and modifications of the device are possible, and the skilled person will readily perceive these. For example, although the device has been described with reference to a single volatile material, it is possible to utilize the device to disseminate two or more such materials. This can be done, for example, by supplying the device with multiple ducts, each leading from a single heated air current source to a different emission source, and providing means for switching between them. This can be arranged manually or automatically, with the possibility of utilizing a timing switch to select a different volatile material at a different time. This is especially useful in the provision of fragrances of air freshening. The change of a fragrance can prevent "habituation" to a single fragrance. Many means of switching between different sources are known to the art.

The device could also utilize control circuitry to intermittently activate the fan and heater or to vary either the speed of the fan or the temperature of the heating element to vary the temperature of the air reaching the emission source to control the level of emission. Such variability may be manually activated by the user and a typical example may be where the fan runs continuously to provide emission due to air flow alone but for boosted emission, the heater is activated for a period.

Typical further embodiments include the provision of remotely-controlled switching, and of catalytic and filtering devices to remove undesirable substances from the atmosphere. A particular embodiment is a catalyst for removal from the atmosphere of undesirable vapours such as carbon monoxide. Such a catalyst may be warmed by the warmed air. Many embodiments are possible and easily realised, examples including precious metals on suitable supports, such as metal monoliths or ceramics, or finely-divided catalyst powders held in porous chambers that allow the air to pass but retain the catalyst.

The devices described herein are easy and inexpensive to make, and are effective in use. The invention is now further described with reference to the accompanying drawings, which depict preferred embodiment s and which are not intended to be in any way limiting,

Figure 1 is a schematic vertical cross-section through an air freshening device

The elements of the device of Figure 1 fit within a housing (not shown).

An air inlet passage 1 has air drawn into it by a blower 2, which is rotated by an electric motor 3 drawing current from a mains power source and control circuit, schematically represented as 4. The air is expelled into an atmosphere through an exit port 5. Downstream from the blower 2 and close to the exit port is located a fragrance emission source. This comprises a reservoir of fragrance 6, from which protrudes a wick 7, the wick and reservoir being arranged such that the wick lies directly in the path of the air from the blower. Wick and refill are in the form of a refill that is easily replaced.

Within the inlet passage is located an electrical heating element 8, which receives power from the same source as does the blower.

In operation, air is sucked into the inlet tube 1 by the blower 2. There it is heated by the heating element before being blown towards the wick, where it picks up fragrance. This is then conveyed into the atmosphere.

The device of Figure 2 is the same as that of figure 1, except there is inserted between the heating element and the blower a catalyst 9, composed of a bed of gold catalyst on iron oxide. This is heated by the warmed air passing the heating element and acts as a remover of undesirable pollutants, such as carbon monoxide.

It is also envisaged that the heated air could be used in conjunction with a catalyst (11) in the inlet to remove toxic gases from the air flow. For example, a precious metal on metal oxide catalyst (e.g. gold on iron oxide) can be used to oxidize carbon monoxide in the air stream. The effect of such reactions can be increased by increasing the temperature of the catalyst and this method provides a means by which this can be achieved.

There are many other embodiments of this invention, which can be realised by means of the ordinary skill of the art, but which fall within the scope of this disclosure.

Claims

Claims:

1. A device adapted to emit into an atmosphere a volatile material, the device comprising a source of volatile material adapted to emit the volatile material into the atmosphere, a heat source adapted to enhance the emission, and a source of forced air current adapted to blow on the source and convey the material into the atmosphere, characterized in that the device is configured so that the heat source heats the air current prior to blowing on the source.

2. A device according to claim 1, in which the source of volatile material is a reservoir from which extends a wick.

3. A device according to claim 1, in which the source of volatile material is a volatile liquid-loaded gel.

4. A device according to claim 3, in which the gel is a maleinised bolybutadiene or maleinised polyisoprene, crosslinked by a diamine.

5. A device according to claim 3, in which the gel is am isocyanate-crosslinked functionalized poly amide.

6. A device according to claim 1, in which the source of volatile material is a sublimable material.

7. A device according to claim 6, in which the sublimable material is selected from adamantane and derivatives thereof, para-dichlorobenzene, 2,4,6-triisopropyl- 1,3,5 - trioxane, camphor, naphthalene, 1,2,3-trichlorobenzene, 1,4-cyclohexanediol, menthol, acetamide, diphenylethane, hexachloroethane, benzoid acid, benzophenone, benzyl cinnamate, benzyl isoeugenol, benzylidene acetone, cedrol, cinnamic alcohol, coumarin, dimethyl fumarate, hydroquinone dimethyl ether, acetyl isoeugenol, methyl cinnamate, methyl coumarin, napthyl ethyl ether, phthalide and thymol.

8. A device according to claim 1, comprising two or more sources of volatile materials, supplied with heated air from a single source by means of multiple ducts, each duct leading from a single heated air current source to a different source, and means for switching between them.

9. A device according to claim 5, in which the switching is automatic and capable of presetting.

10. A device according to claim 1, in which the source of volatile material is supplied in the form of a replaceable refill.

11. A method of providing a volatile material in an atmosphere, comprising the blowing of a forced air current on a source of volatile material, characterized in that the forced air current is heated prior to blowing on the source.