US20230354893A1

US20230354893A1 - A Liquid Substance Storing Container for an Aerosol Generating Device

Info

Publication number: US20230354893A1
Application number: US18/027,849
Authority: US
Inventors: Broderick Coburn; Joao Seco
Original assignee: JT International SA
Current assignee: JT International SA
Priority date: 2020-10-05
Filing date: 2021-10-01
Publication date: 2023-11-09
Also published as: WO2022073887A1; EP4225083A1; CA3194791A1

Abstract

A liquid substance storing container for an aerosol generating device includes a porous body for storing liquid substance.

The porous body includes a closed internal cavity further storing a volume of the liquid substance.

The aerosol generating device including the liquid substance storing container may be used as an e-cigarette.

Description

FIELD OF THE INVENTION

The present invention relates to a liquid substance storing container for an aerosol generating device.
It also concerns an aerosol generating device comprising such a liquid substance storing container.

BACKGROUND OF THE INVENTION

Aerosol generating devices, also commonly called vaporizers or electronic cigarettes, allow vaporization of a substance to create an aerosol or mist that a user inhales.
An aerosol generating device comprises a heat source that heats the substance, generally a liquid often called e-liquid or e-juice, to create the aerosol in a vaporization zone of the aerosol generating device. Channels are also provided for routing the aerosol from the vaporization zone to a mouth piece for the user.
The aerosol generating device often comprises a reservoir configured for storing the substance in liquid form, and feeders configured for moving the substance from the reservoir, such as by wicking or capillary action, to a vaporization zone for heating or vaporization.
This type of configuration needs to provide sealing means to seal a liquid outlet hole on the reservoir.
In order to avoid the drawbacks of a reservoir, such as liquid leakages, US 2018/0289909 discloses a vaporizer adapted to vaporize oil that is stored in one or several tabs.
The tab, such as a tablet, cylinder, or disk, can include a porous body for storing liquid substance. For example, the tab can include a piece of porous ceramic or sintered metal soaked, injected or infused with oil, such as to the point that the oil is held in place by capillary action.
In such an embodiment, the vaporizer can include a reservoir configured for holding one or more tabs and for supporting the tabs during heating.
Such a tab provides a medium for storing, transporting and allowing vaporization of a substance.
However, the quantity of oil or liquid substance stored in the tab is limited, and depends on the porosity of the tab. Thus, the packing efficiency, that is the ratio between the vaporizable substance volume stored in the storage medium and the volume occupied by the storage medium (or overall volume), is rather low, and limited by the volume of the vaporizable substance which can be stored in the pores of the porous body of the tab.
The present invention aims to improve the packing efficiency of a liquid substance storing container for an aerosol generating device.

SUMMARY OF THE INVENTION

The present invention thus relates to a liquid substance storing container for an aerosol generating device, comprising a porous body for storing liquid substance.
According to the invention, the porous body includes a closed internal cavity surrounded by wall of the porous body, said closed internal cavity further storing liquid substance by forming a closed pocket.
Thus, the volume of stored liquid substance in the storing container may be increased compared to a storing container made of the same porous body, without a closed internal cavity.
Indeed, the volume of stored liquid substance is not limited to the volume of the liquid substance which can be stored in the pores of the porous body of the tab, but also comprise the volume of the liquid substance stored in the closed internal cavity.
The packing efficiency is thus improved compared to a storing container made of a homogenous porous body with no internal cavity.
Such a liquid substance storing container allows a significant optimization of the volume of stored liquid substance, thanks to the closed internal cavity which provides the storing container with an internal reservoir of liquid substance.
According to one embodiment, the porous body is adapted to absorb a volume of liquid substance and to retain said volume of liquid substance until vaporized.
The liquid substance is then absorbed by capillary action in the porous body and goes through the porous body up to the closed internal cavity in order to be stored therein. The volume of liquid substance is then retained both in the closed internal cavity and the walls of the porous body surrounding the closed internal cavity.
In practice, the porous body has an open-cell structure.
According to one embodiment, the open-cell structure of the porous body is adapted to retain the liquid substance in the closed internal cavity in a leak-proof manner when said porous body is maintained below a threshold temperature of 50° C.
Thus, the storing container is well adapted to store a liquid substance before its heating and vaporization. The storing container may be manipulated by a user without risk of leakage, before using in an aerosol generating device.
Advantageously, the open-cell structure of the porous body is adapted to release the liquid substance from the closed internal cavity into the porous body by capillary action when said porous body is heated at or above said threshold temperature.
As a consequence, the liquid substance stored in the closed internal cavity goes gradually into the porous body.
In practice, the open-cell structure of the porous body is adapted to release, through an outer surface of said porous body, a vaporized liquid substance when said porous body is heated at or above said threshold temperature.
In one embodiment, the pore size of the open-cell structure of said porous body ranges between 0.5 to 100 micrometers.
As an example, the porous body is made of porous ceramic, sintered metal, sintered glass or alumina.
In one configuration, the porous body takes the shape of a disk, a cylinder, a hexagonal prism, or sphere.
In another configuration, the porous body takes the shape of a hollow cylinder or a hollow truncated cone.
The hollow form of the porous body may facilitate the handling of the storing container and/or the cooperation of the storing container with a heating unit in the aerosol generating device.
In one embodiment, the closed internal cavity has a three-dimensional shape homothetic to the shape of said porous body.
Preferably, the three-dimensional shape of the closed internal cavity is concentric with the shape of said porous body.
The closed internal cavity is thus centred in the porous body. The liquid substance stored in the closed internal cavity can go homogeneously, through all the walls of the porous body surrounding the closed internal cavity.
According to another aspect, the present invention relates to an aerosol generating device comprising a liquid substance storing container as recited above, and a heater adapted to heat the porous body at or above a threshold temperature of 50° C.
The aerosol generating device present the same advantages as the ones described in relation with the liquid substance storing container.
In one embodiment, the heater is adapted to heat an outer surface of said porous body.
In another embodiment, the porous body has a hollow shape and the heater is adapted to heat an inner surface of the hollow porous body.
Such a heating through an inner surface of the hollow porous body may improve the transfer of heat to the storing container, in order to speed up the temperature rise in the porous body, and thus the vaporization of the liquid substance.

BRIEF DESCRIPTION OF THE DRAWINGS

Other particularities and advantages of the invention will also emerge from the following description.

In the accompanying drawings, given by way of non-limiting examples:

FIG. 1A represents, in a schematic three dimensional view, a liquid substance storing container according to a first embodiment of the invention;

FIG. 1B represents, in a schematic sectional view, the liquid substance storing container of FIG. 1A;

FIG. 2 represents, in a schematic three dimensional view, a liquid substance storing container according to a second embodiment of the invention;

FIG. 3 represents, in a schematic sectional view, a liquid substance storing container according to a third embodiment of the invention;

FIG. 4A represents, in a perspective view, a liquid substance storing container according to a fourth embodiment of the invention;

FIG. 4B represents, in a schematic sectional view, the liquid substance storing container of FIG. 4A; and

FIG. 5 is a schematic view of an aerosol generating device according to one embodiment of the invention.

DETAILED DESCRIPTION

FIGS. 1A and 1B depict a liquid substance storing container according to a first embodiment.
It should be noted that liquid substance storing container is a consumable item, configured to be used with an aerosol generating device, such as an electronic cigarette (e-cigarette). Once the liquid substance initially retained in the storing container has been aerolized and thus consumed, the storing container may be replaced by another liquid substance storing container. The old storing container can be discarded, preferably for recycling.
In the following, the liquid substance encompasses any types of vaporizable substances including oil, water, ..., which may be vaporized to form a mist capable of being inhaled by a user.
As an example, the liquid substance may be a e-liquid well known for using in the e-cigarettes. Extracts from the cannabis plant can also take the form of an oil or oil-like substance.
The liquid substance storing container 10 comprises a porous body 11 for storing the liquid substance.
The porous body 11 may be made of porous ceramic, sintered metal, sintered glass, alumina or silicon carbide.
The porous body 11 has an open-cell structure, with a matrix of pores adapted to absorb and then to retain, by capillary action, the liquid substance until vaporized.
The pore size of the open-cell structure of the porous body 11 ranges between 0.5 to 100 micrometers.
As an example, the pore size of the porous body may be equal to 15 micrometers, with the ability to retain 0.5 micrometers particle.
Thanks to its porosity, the porous body 11 may absorb a volume of liquid substance, for example by infusing: the porous body is immersed in a liquid bath and the liquid is sucked into the pores of the porous body 11 by capillary action.
As depicted in FIG. 1A, the porous body 11 includes a closed internal cavity 12.
The closed internal cavity 12 is thus a recess or a chamber surrounded by the walls 11 a of the porous body 11.
The closed internal cavity 12 thus forms a closed pocket or reservoir in the porous body itself, for storing liquid substance.
When the porous body 11 is loaded with the liquid substance, the liquid substance fills both the pores of the porous body 11 and the closed internal cavity 12.
Thus, the volume of the liquid substance stored in the liquid substance storing container 10 is increased, and is not limited to the volume of liquid substance retained in the pores of the porous body 11.
Taking the overall volume Ve occupied by the porous body 11 and the internal volume Vc of the closed internal cavity 12, the volume Vs of the liquid substance stored in the liquid substance storing container 10 is:
$Vs = (Ve - Vc) \times e_{p} + V_{c}$
wherein e_p is the packing efficiency of the porous material of the porous body 11.
The packing efficiency of a porous material is the ratio, inferior to 1, between the liquid substance volume which can be stored in the pores of a storage medium made in the porous material and the volume occupied by the storage medium.
Thanks to the closed internal cavity 12, the volume of the stored liquid substance may be increased compared to the volume (Ve x e_p) which would be stored in a porous body 11 of the same shape, without a closed internal cavity.
Thus, the number of puffs per liquid substance storing container 10 is also increased when the liquid substance storing container 10 is used in a vaporizer.
The liquid substance may be loaded in the closed internal cavity 12 and the porous body 11 by infusing: the liquid substance storing container 10 can be heated, for example at 60° C. about, and immersed in a liquid substance bath. The liquid substance is sucked into the pores of the porous body 11 by capillary action and also into the closed internal cavity 12, though the walls of the porous body 11.
Alternatively, or in addition, means of pressure may be used in order to load the liquid substance into the closed internal cavity 12 and the porous body 11.
In this first embodiment, the porous body 11 takes the shape of a disk or a cylinder, with a height H and a cross-sectional surface S. The volume Ve occupied by the porous body 11 or the volume envelope is:
$Ve = H \times S .$
As illustrated in FIGS. 1A and 1B, the closed internal cavity 12 has a three-dimensional shape homothetic to the shape of the porous body 11.
Here, the closed internal cavity 12 takes also the shape of a disk or a cylinder, with a height H1 and a cross-sectional surface S1. The volume Vc of the closed internal cavity 12 is:
$Vc = H1 \times S1 .$
Depending on the volume Vc of the closed internal cavity 12, the packing efficiency of the liquid substance storing container 10 may be more or less increased.
Preferably, the three-dimensional shape of the closed internal cavity 12 is concentric with the shape of the porous body 12.
In this first embodiment, the cylindrical shape of the closed internal cavity 12 has the same central longitudinal axis X as the one of the cylindrical shape of the porous body 11, and the centres of the cylindrical shapes of the closed internal cavity 12 and the porous body 11 are merged.
The thickness of the walls 11 a of the porous body 11 surrounding the closed internal cavity 12 is thus identical in any directions around the closed internal cavity 12.
In the first embodiment, the thicknesses t of the top, bottom and side walls 11 a of the porous body 11 are the same.
Of course, the shapes of the porous body and the closed internal cavity are not limitative.
In particular, the closed internal cavity 12 may also be non-homothetic to the shape of the porous body 11 and/or be non-concentric with the shape of the porous body 11.
As depicted in FIG. 2 , in a second embodiment, the porous body 21 of the liquid substance storing container 20 may also take the shape of a hexagonal prism, the closed internal cavity 22 taking a same homothetic shape of a hexagonal prism or another shape.
In a third embodiment of a liquid substance storing container 30 as depicted in FIG. 3 , the porous body 31 may also take the shape of a sphere or a ball, the closed internal cavity 32 taking also the shape of a sphere, for example concentrically disposed in the porous body 31.
In a fourth embodiment as depicted in FIGS. 4A and 4B, the porous body 41 of a liquid substance storing container 40 takes the shape of a truncated cone, with a longitudinal axis Y. The closed internal cavity 42 has also the shape of truncated cone, disposed along the same longitudinal axis Y as the one of the porous body 41.
In this fourth embodiment, the porous body 41 is hollow. In this embodiment, the hollow truncated cone has a hole 45 which extends along the longitudinal axis Y of the porous body 41.
The hole 45 takes in this embodiment a frusto-conical shape, centrally disposed in the porous body 41.
Of course, this fourth embodiment with a hollow porous body 41 is not limitative. For example, the hollow porous body may take the shape of a hollow cylinder, with a cylindrical hole. The closed internal cavity takes also the shape of a hollow cylinder.
The hole 45 of the porous body 41 is configured to fit with a heating element of an aerosol generating device.
The liquid substance storing container 10, 20, 30, 40 as described here above forms a solid consumable comprising a porous body 11, 21, 31, 41 configured to retain the liquid substrate at an ambient temperature and to release and vaporize the liquid substrate when heated to form an aerosol.
Thus, the porous body 11, 21, 31, 41 resists egress or leakage of liquid substrate through the pores of the porous material absent heating and vaporization of the liquid substrate.
Thus, the porous body 11, 21, 31, 41 also retain the liquid substance in the closed internal cavity 12, 22, 32, 42 in a leak-proof manner when the porous body is maintained below a threshold temperature, and is not heated.
The threshold temperature is set for instance to 50° C., so that the liquid substance storing container 10, 20, 30, 40 may be stored and transported without liquid leakage before use, by keeping the liquid substance storing container 10, 20, 30, 40 at room or ambient temperature.
On the contrary, when the porous body 11, 21, 31, 41 is heated at or above the threshold temperature, the open-cell structure of the porous body 11, 21, 31, 41 is adapted to release, through its outer surface, a vaporized liquid substance.
More precisely, the liquid substance heated in the pores of the porous body 11, 21, 31, 41, and mainly in the pores of the walls 11 a, 21 a, 31 a, 41 a of the porous body 11, 21, 31, 41, is vaporized and released from the porous body 11, 21, 31, 41.
Thus the liquid substance exudes through the porous walls 11 a, 21 a, 31 a, 41 a only when the porous body 11, 21, 31, 41 is heated via an external heater, above the threshold temperature.
The liquid substance is gradually released from the closed internal cavity 12, 22, 32, 42 into the porous body 11, 21, 31, 41, by capillary action, when the liquid substance retained in the pores of the porous body 11, 21, 31, 41 is vaporized.
The closed internal cavity 12, 22, 32, 42 ensures the replenishment of liquid substance in the pores of the porous body from the closed internal cavity 12, 22, 32, 42. The closed internal cavity 12, 22, 32, 42 acts as a reservoir for fulfilling the pores of the porous material 11, 21, 31, 41.
The heating of the liquid substance in the pores of the porous body 11, 21, 31, 41 may be obtained in a continuous manner, with the gradual replenishment of the pores of the porous body 11, 21, 31, 41.
Of course, the examples given here below of a liquid substance storing container 10, 20, 30, 40 are not limitative.
For instance, the internal walls of the closed internal cavity 12 may be provided with ridges or grooves in order to increase the internal area of the closed internal cavity 12 in contact with the porous body 12. The transfer of the liquid substance from the closed internal cavity 12 into the porous body 11 is thus increased, ensuring a fast replenishment by capillary action of the pores of the porous body 12.
By way of example, an aerosol generating device 50 which could be used for heating a liquid substance storing container 10, 20, 30, 40 is depicted in FIG. 5 according to one embodiment of the invention.
The aerosol generating device 50 may comprise as usual a housing 51 with a mouth piece 52 at one end for inhalation of the vapour or a mist by a user.
The aerosol generating device 50 also comprise a heater 53 adapted to heat a liquid substance storing container 10, 20, 30, 40.
As described here above, the heater is adapted to heat the porous body of the liquid substance storing container 10, 20, 30, 40 at or above the threshold temperature, here set at 50° C.
In this non limitative embodiment, the liquid substance storing container 10, 20, 30, 40 is disposed in a vaporization chamber 54, and the heater 53 is adapted to heat an outer surface of the porous body of the liquid substance storing container 10, 20, 30, 40 for vaporizing the liquid substance retained in the pores of the porous body.
The heater 52 may be a direct heating source such as a laser, a LED (Light Emitting Diode), a flame or a heating resistance.
The heater 52 may also be an indirect source such as a flowing or stagnant air which has been heated.
Generally, the heater 53 is an electrical heating element and is powered by a battery 55.
The vaporized liquid substance is routed via flow channels (not illustrated) from the vaporization chamber 54 to the mouth piece 52, crossing preferably a filter 56 disposed upstream from a output 52 a of the mouth piece 52.
Of course, this embodiment of the aerosol generating device is not limitative.
In particular, when the porous body 41 has a hollow shape as depicted in FIGS. 4A and 4B, the heater may be adapted to heat an inner surface 45 a of the hollow porous body 41.
Thus, the heater may be configured to fit into the hole 45 of the porous body 41. The heater is in contact with the internal surface 45 a of the hole 45 for heat conduction to the porous body 41. Preferably, the external surface of the heater matches the internal surface 45 a of the hole 45 of the porous body 41 of the liquid substrate storing container 40.
Thanks to the invention, an improved liquid substance storing container may be provided as a consumable for an electronic cigarette, with a higher liquid content rate compared to a consumable having the same overall volume and a homogeneous porous body, without internal cavity.
Due to the improved packing efficiency, smaller storing container may be formed, compared to a homogeneous porous body without closed internal cavity, for a predetermined volume of vaporizable liquid substance.
Alternatively, for a predetermined envelope or overall volume of the porous body, a higher volume of vaporizable liquid substance may be stored in the storing container thanks to the presence of the closed internal cavity.

Claims

1. A liquid substance storing container for an aerosol generating device, comprising a porous body for storing liquid substance, wherein said porous body includes a closed internal cavity surrounded by walls of the porous body, said closed internal cavity further storing liquid substance by forming a closed pocket.

2. The A-liquid substance storing container according to claim 1, wherein said porous body is adapted to absorb a volume of liquid substance and to retain said volume of liquid substance until vaporized.

3. The A-liquid substance storing container according to claim 1, wherein the porous body has an open-cell structure.

4. The liquid substance storing container according to claim 3, wherein the open-cell structure of the porous body is adapted to retain the liquid substance in the closed internal cavity in a leak-proof manner when said porous body is maintained below a threshold temperature of 50° C.

5. The A-liquid substance storing container according to claim 4, wherein the open-cell structure of the porous body is adapted to release the liquid substance from the closed internal cavity into the porous body by capillary action when said porous body is heated at or above said threshold temperature.

6. The A-liquid substance storing container according to claim 5, wherein the open-cell structure of the porous body is adapted to release, through an outer surface of said porous body, a vaporized liquid substance when said porous body is heated at or above said threshold temperature.

7. The liquid substance storing container according to claim 3, wherein the pore size of the open-cell structure of said porous body ranges between 0.5 to 100 micrometers.

8. The liquid substance storing container according to claim 1, wherein said porous body is made of porous ceramic, sintered metal, sintered glass or alumina.

9. The liquid substance storing container according to claim 1, wherein said porous body takes the shape of a disk, a cylinder, a hexagonal prism, or sphere.

10. The liquid substance storing container according to claim 1, wherein said porous body takes the shape of a hollow cylinder or a hollow truncated cone.

11. The liquid substance storing container according to claim 9, wherein said closed internal cavity has a three-dimensional shape homothetic to a shape of said porous body.

12. The liquid substance storing container according to claim 11, wherein the three-dimensional shape of the closed internal cavity is concentric with the shape of said porous body.

13. An aerosol generating device comprising a liquid substance storing container according to claim 1; and a heater adapted to heat said porous body at or above a threshold temperature of 50° C.

14. The aerosol generating device according to claim 13, wherein said heater is adapted to heat an outer surface of said porous body.

15. The aerosol generating device according to claim 13, wherein said porous body has a hollow shape, said heater adapted to heat an inner surface of the hollow porous body.

16. The liquid substance storing container according to claim 10, wherein said closed internal cavity has a three-dimensional shape homothetic to a shape of said porous body.