阅读说明：本技术 用于气溶胶生成装置的液体供应系统 (Liquid supply system for an aerosol-generating device ) 是由 I·陶里诺 于 2019-10-01 设计创作，主要内容包括：一种用于与气溶胶生成装置一起使用的液体供应系统,液体供应系统包括液体保持材料(136)、从液体保持材料延伸的液体流动通道,以及设置在液体流动通道中的屏障(125),屏障具有60℃至120℃之间的阈值温度,其中屏障在其阈值温度以下不可渗透液体,并且在阈值温度以上变为可逆地可渗透液体。(A liquid supply system for use with an aerosol-generating device, the liquid supply system comprising a liquid retaining material (136), a liquid flow passage extending from the liquid retaining material, and a barrier (125) disposed in the liquid flow passage, the barrier having a threshold temperature between 60 ℃ and 120 ℃, wherein the barrier is impermeable to liquid below its threshold temperature and becomes reversibly permeable to liquid above the threshold temperature.)

1. A liquid supply system for use with an aerosol-generating device, the liquid supply system comprising:

a liquid retaining material;

a liquid flow channel extending from the liquid retaining material; and

a barrier disposed in the liquid flow channel, the barrier having a threshold temperature between 60 ℃ and 120 ℃, wherein the barrier is impermeable to liquid below the threshold temperature of the barrier and the barrier becomes reversibly permeable to liquid above the threshold temperature.

2. The liquid supply system of claim 1, wherein the barrier comprises a material having a threshold temperature between 70 ℃ and 120 ℃.

3. The liquid supply system according to any one of the preceding claims, further comprising: a liquid transport material disposed on a downstream side of the liquid retention material.

4. The liquid supply system of claim 3, wherein the barrier is disposed on a downstream side of the liquid transport material, or between the liquid transport material and the liquid retention material.

5. The liquid supply system according to any one of the preceding claims, wherein the liquid supply system further comprises: a liquid storage portion provided on an upstream side of the liquid holding material.

6. The liquid supply system according to claim 5, wherein the barrier is disposed between the liquid retaining material and the liquid storage portion.

7. The liquid supply system of any one of the preceding claims, wherein the barrier comprises a deposited film, coating, or stacked layer disposed on the liquid retaining material, the liquid transport material, or both the liquid retaining material and the liquid transport material.

8. The liquid supply system according to any one of the preceding claims, wherein the barrier comprises a polymer layer and a temperature reactive material dispersed therein, wherein the temperature reactive material forms pores in the polymer layer above the threshold temperature.

9. The liquid supply system of claim 8, wherein the temperature reactive material comprises linear polymer chains, cross-linked hydrogel networks, microspheres, or a combination thereof.

10. The liquid supply system of claim 8 or 9, wherein the temperature reactive material comprises a covalently crosslinked reversible polymer comprising a (allylurea-allylamine) copolymer (PAU-Am), a poly (pentafluorophenyl acrylate), or a combination thereof.

11. The liquid supply system of claim 9, wherein the temperature reactive material comprises poly (N-isopropylacrylamide) (PNIPAAm), poly (2-ethyl-2-oxazoline) (PEOx), poly (2-ethyl-2-oxazine) (PEOZI), PEO-b-PPO block copolymer, Hydroxypropylmethylcellulose (HPMC), or a combination thereof.

12. A cartridge for use with an aerosol-generating device, the cartridge comprising:

a housing;

a liquid supply system according to any preceding claim disposed in the housing; and

a quantity of liquid aerosol-forming substrate contained in the liquid retaining material.

13. An aerosol-generating system comprising:

a cartridge comprising the liquid supply system of any one of claims 1-11 disposed in the cartridge, and a liquid disposed within the liquid supply system; and

an aerosol-generating device configured to receive the cartridge; heating the barrier to a temperature above the threshold temperature; and heating at least a portion of the liquid supplied from the liquid retaining material.

14. An aerosol-generating system comprising:

a cartridge comprising the liquid supply system of claim 3 or claim 4 disposed in the cartridge, and a liquid disposed within the liquid supply system; and

an aerosol-generating device configured to receive the cartridge; heating the barrier to a temperature above the threshold temperature; and heating the liquid transport material to a temperature of about 200 ℃ or greater to aerosolize at least a portion of the liquid once the liquid has been transferred to the liquid transport material.

Technical Field

The present invention relates to an electrically heated aerosol-generating system and associated devices, articles and methods. In particular, the present invention relates to systems and methods for storing liquid aerosol-forming substrates for use in such aerosol-generating systems. The present disclosure further relates to barrier materials for preventing leakage of liquid aerosol-forming substrates from such systems and from components of such systems.

Background

One type of aerosol-generating system is an electrically operated elongate handheld aerosol-generating system having a mouth end and a distal end. Known hand-held electrically operated aerosol-generating systems may comprise: a device part comprising a battery and control electronics, a cartridge part comprising a supply of aerosol-forming substrate, and an electrically operated vaporizer. A cartridge comprising both a supply of aerosol-forming substrate and a vaporiser is sometimes referred to as a "cartridge". The vaporiser may comprise a coil of heater wire wound around an elongate wick soaked in the liquid aerosol-forming substrate. However, some vaporizers include a heater grid formed into a substantially planar shape and placed on top of the surface of the transfer material (e.g., wick). A capillary material soaked in the aerosol-forming substrate supplies liquid to the wick. When a user draws on the mouth end of the system, air is drawn into the vaporizer, and the heater is turned on and vaporizes the aerosol-forming substrate. A mouthpiece opening at the mouth end of the system allows the user to inhale the generated aerosol.

The liquid aerosol-forming substrate of the aerosol-generating system may be provided in a liquid supply system (e.g. a cartridge) comprising a High Retention Material (HRM) for storing the liquid aerosol-forming substrate. When the system is used, the liquid substrate may be transferred from a high retention material to a Transport Material (TM), where the aerosol-forming substrate material may be heated and vaporised. However, during storage, it is desirable that the liquid matrix not transfer to the transfer material and leak from the cartridge.

Disclosure of Invention

It would be desirable to inhibit early leakage of aerosol-forming substrate from the cartridge. It would further be desirable to facilitate allowing transfer of the liquid aerosol-forming substrate to the heating element and into the airflow passage when the aerosol-generating system is in use.

In various aspects of the invention, an aerosol-generating system having a mouth end and a distal end is provided. The system may comprise a liquid storage portion for containing the aerosol-forming substrate. The system may further comprise a cover disposed over the liquid storage portion, and one or more air flow passages or channels between the cover and the liquid storage portion. The system may comprise a heating element configured to heat the liquid aerosol-forming substrate.

The system may comprise an aerosol-generating device or base unit configured to receive a cartridge of aerosol-forming substrate contained in a high retention material. The system may further comprise a transport material configured to deliver the aerosol-forming substrate to the heating element when the aerosol-generating system is in use.

The cartridge may include a barrier layer to prevent premature transfer of the liquid matrix into the airflow path. The cartridge may include a liquid flow passage having an upstream end and a downstream end. The liquid flow channel may extend from an upstream end at which liquid is stored (e.g., from the liquid storage portion or the high retention material) to a downstream end at the gas flow path. The barrier layer may be disposed at various locations along the liquid flow path such that the barrier is located between the stored liquid matrix and the airflow path. For example, the barrier layer may be disposed on the heating element (between the heating element and the airflow path), between the transfer material and the heating element, between the high retention material and the transfer material, between the high retention material and the heating element, or between the liquid storage portion and the high retention material. The barrier may prevent transfer of the liquid matrix from the high retention material or from the liquid storage portion to the transport material, the heating element, or the airflow path. The barrier layer is impermeable to liquid below a threshold temperature and becomes liquid-permeable reversibly at or above the threshold temperature (as may be achieved during use of the system), thereby allowing liquid to be transferred along the liquid flow path. According to some aspects of the invention, the barrier layer may be an impermeable film or a hydrophobic coating.

In one embodiment, the barrier layer is disposed downstream of the heater. In one embodiment, the barrier layer is disposed upstream of the heater, such as between the heater and the transfer material or between the heater and the high retention material. In one embodiment, the barrier layer is disposed upstream of the transfer material, such as between the transfer material and the high retention material. In one embodiment, the barrier layer is disposed upstream of the high retention material, such as between the high retention material and the liquid storage portion. In some embodiments, the cartridge includes multiple barrier layers, and the barrier layers may be disposed at any combination of the above locations.

The system of the present application may reduce or prevent leakage of the liquid aerosol-forming substrate during storage. The system is convenient to use because the barrier layer does not need to be manually removed or peeled off prior to use. For example, when the system is in use, the system allows for liquid transfer during normal use of the device.

The invention further provides aerosol-generating systems and devices that use electrical energy to heat a substrate to form an aerosol that can be inhaled by a user without the need to burn the substrate. Preferably, the system is compact enough to be considered a handheld system. Some examples of the systems of the present invention can deliver a nicotine-containing aerosol for inhalation by a user.

The term "aerosol-generating" article, device or system refers to an article, device or system capable of releasing volatile compounds from an aerosol-forming substrate to form an aerosol that can be inhaled by a user. The term "aerosol-forming substrate" refers to a substrate which is capable of releasing volatile compounds which form an aerosol when heated. A liquid aerosol-forming substrate is a substrate that is liquid at ambient temperature, for example from about 15 ℃ to about 30 ℃. Liquid aerosol-forming substrates are considered to include liquid solutions, suspensions, dispersions and the like.

Any suitable aerosol-forming substrate may be used with the system. Suitable aerosol-forming substrates may comprise a plant based material. For example, the aerosol-forming substrate may comprise tobacco or a tobacco-containing material containing volatile tobacco flavour compounds which are released from the aerosol-forming substrate upon heating. Additionally or alternatively, the aerosol-forming substrate may comprise a tobacco-free material. The aerosol-forming substrate may comprise a homogenized plant-based material. The aerosol-forming substrate may comprise at least one aerosol-former. Examples of aerosol-forming agents include: polyhydric alcohols such as triethylene glycol, 1, 3-butanediol, propylene glycol, and glycerin; esters of polyhydric alcohols, such as monoacetin, diacetin, or triacetin; and aliphatic esters of mono-, di-or polycarboxylic acids, such as dimethyl dodecanedioate and dimethyl tetradecanedioate. The aerosol-forming substrate may comprise other additives and ingredients such as flavourants. Preferably, the aerosol-forming substrate comprises nicotine. Preferably, the aerosol-forming substrate is a liquid aerosol-forming substrate. In some embodiments, the aerosol-forming substrate comprises glycerol, propylene glycol, water, nicotine and optionally one or more flavourants.

According to aspects of the present disclosure, the aerosol-forming substrate may be stored in a liquid storage portion of the system and/or in the cartridge. The liquid storage portion may be part of a consumable portion (e.g. a cartridge) that can be replaced by a user when the supply of aerosol-generating substrate in the liquid storage portion is reduced or exhausted. For example, a used liquid storage portion may be replaced with another liquid storage portion filled with an appropriate amount of aerosol-forming substrate. The cartridge may also be free of aerosol-forming substrate and a user may fill the cartridge (e.g. liquid storage portion or high retention material) with the desired substrate through a liquid port provided on the cartridge. In some embodiments, the liquid storage portion is not refillable by a user.

According to some aspects, the cartridge does not comprise a liquid storage compartment. Instead, the aerosol-forming substrate may be stored in a high retention material. In embodiments that do not comprise a liquid storage compartment, the amount of liquid aerosol-forming substrate, and hence the number of puffs available from the device, may be less than from a device that comprises a liquid storage compartment.

Aspects of the present disclosure relate to liquid storage units and systems. The liquid storage unit may be a liquid storage portion of a cartridge that includes both the liquid storage portion and the heating element. Alternatively, the liquid storage unit may be removably connected to a separate module having a heating element. Such liquid storage units may be referred to as "bladders". While the liquid storage unit described in this disclosure may be generally referred to as a cartridge (liquid supply system), aspects of the invention are equally applicable to a bladder (liquid storage unit).

Preferably, the system comprises a cartridge releasably connectable to the base unit. As used herein, "releasably connectable" means that releasably connectable components can be connected and disconnected from each other without significant damage to either component. The cartridge may be connected to the base unit in any suitable manner, such as a threaded engagement, a snap-fit engagement, an interference fit engagement, a magnetic engagement, or the like.

If the system comprises a separate vaporisation unit (e.g. a separate unit containing a heating element) and the capsule, the capsule may comprise a valve positioned relative to the distal end portion opening to prevent aerosol-forming substrate from leaving the reservoir when the capsule is not connected to the vaporisation unit. The valve may be actuatable such that the act of connecting the bladder to the evaporation unit causes the valve to open, and the act of disconnecting the bladder from the evaporation unit causes the valve to close. Any suitable valve may be used.

The liquid supply system includes a housing, which may be a rigid housing. As used herein, "rigid housing" means a self-supporting housing. The housing may be formed of any suitable material or combination of materials, such as a polymeric material, a metallic material, or glass. Preferably, the housing of the liquid storage portion may be formed of a thermoplastic material. Any suitable thermoplastic material may be used. In a preferred example, a passage is defined through the housing forming at least a portion of the aerosol flow path.

The liquid storage unit comprises an aerosol-forming substrate in a high retention material, a transport material configured to deliver the aerosol-forming substrate to the heating element, and a barrier layer or coating between the high retention material and the transport material. The barrier layer may have a reversible barrier quality. That is, the barrier layer may become reversibly permeable above a threshold temperature. A "high retention material" is a material that is capable of absorbing and/or storing a liquid (e.g., an aqueous liquid), and is capable of transporting the liquid (e.g., by capillary action) to a transport material. A "transport material" is a material, such as a wick, that effectively transports liquid from one end of the material to the other, for example, by capillary action. The term "barrier" refers to the property of a layer to make it impermeable to liquids or to prevent the transfer of liquids. The term "prevent" has the meaning of at least partial stopping or inhibiting herein and includes complete stopping or inhibiting. The term "reversible" barrier means that the barrier quality (e.g., permeability of aqueous liquids) may be lost and restored depending on environmental conditions (e.g., temperature).

The high retention material may have a fibrous or sponge structure. Preferably, the high retention material comprises a web, mat or bundle of fibers. The fibers may be substantially aligned to convey liquid in the aligned direction. Alternatively, the high retention material may comprise a sponge-like or foam-like material. The high retention material may comprise any suitable material or combination of materials. Examples of suitable materials are sponges or foams, ceramic or graphite-like materials in the form of fibers or sintered powders, or fibrous materials made, for example, of spun or extruded fibers, ceramics or glass.

When the cartridge is coupled with the base unit of the aerosol-generating device, at least a portion of the transport material is located sufficiently close to the heating element that the liquid aerosol-forming substrate carried by the transport material can be heated by the heating element to produce an aerosol. The transfer material is preferably in contact with the heating element. Alternatively, there may be an intermediate layer between the transmission material and the fluid permeable heating element, wherein the intermediate layer assists in providing fluid communication between the transmission material and the heating element. In another alternative embodiment where the cartridge does not include a transfer material, the heating element may heat the barrier layer directly or through a high retention material.

Any suitable heating element may be employed. Preferably, the heating element comprises a fluid permeable heating element. The fluid permeable heating element may be substantially flat and may be made of electrically conductive filaments. The conductive filaments may lie substantially in a single plane. Alternatively, the substantially planar heating element may be curved in one or more dimensions, forming, for example, a conical shape, a dome shape, an arc shape, or a bridge shape.

Alternatively, the fluid permeable heating element may form a hollow tubular or cylindrical shape. The hollow tubular or cylindrical shape may be made of conductive filaments. The hollow tubular or cylindrical shape may be formed by any suitable method, such as, for example, rolling a substantially flat heating element comprising electrically conductive filaments. The conductive filaments may form side surfaces of a hollow tubular or cylindrical shape. The cross-section of the hollow tubular or cylindrical heater may be circular, elliptical or polygonal.

The heating element may be an internal heating element (inside the cartridge) or an external heating element (part of the aerosol-generating device and outside the cartridge). The heating element may be disposed adjacent the barrier layer, adjacent the transfer material, adjacent the high retention material, or adjacent the liquid storage portion, or a combination thereof. If the heating element is an external heating element, the components of the cartridge may be arranged to accommodate the external heating element such that the desired components are adjacent the heating element when the cartridge is installed in the aerosol-generating device.

The heating element may comprise a resistive wire. The term "wire" refers to an electrical path disposed between two electrical contacts. The filaments may have a circular, square, flat or any other form of cross-section and may have a diameter between 10 μm and 100 μm. The filaments may be arranged in a straight or curved manner and may be branched, divergent and convergent. The one or more resistive wires may form a coil, a grid, an array, a fabric, or the like. Application of current to the heating element causes heating due to the resistive nature of the element. In some preferred embodiments, the heating elements form a grid, array or fabric arranged in a substantially flat shape.

Preferably, the heating element is fluid permeable. This may be achieved by arranging the conductive filaments such that a gap between 10 μm and 100 μm is formed between the filaments. The filaments may cause capillary action in the void such that, in use, liquid to be evaporated is drawn into the void, thereby increasing the contact area between the heating element and the liquid. The electrically conductive filaments may form a mesh having a mesh size of between 160 and 600 mesh US (+/-10%) (i.e., between 63 and 236 filaments per centimeter (+/-10%) (i.e., between 160 and 600 filaments per inch (+/-10%))²。

The lattice may be formed using different types of weaves or lattice structures or arrays of parallel filaments. The filaments may be formed individually and woven together to form a mesh, or the filaments may be formed by etching a sheet material such as a foil.

The filaments of the heating element may be formed of any material having suitable electrical properties. Suitable materials include, but are not limited to: such as a ceramic-doped semiconductor, a conductive ceramic (e.g., such as molybdenum disilicide), carbon, graphite, a metal alloy, a composite material made of a ceramic material and a metallic material, and combinations thereof. Preferably, the filaments are made of wire. More preferably, the wire is made of metal, most preferably stainless steel.

The system of the present disclosure comprises a cartridge with a high retention material to retain the liquid aerosol-forming substrate. In some examples, the high retention material is arranged to transfer the liquid aerosol-forming substrate to the transport material during use. In some examples, the cartridge does not comprise a transport material, and the high retention material is arranged to convey the liquid aerosol-forming substrate directly to the heating element or the airflow passage.

The high retention material may comprise a capillary material having a fibrous or porous structure that forms a plurality of small pores or microchannels. The liquid aerosol-forming substrate may be transported by capillary action through the capillary material. The high retention material may comprise a plurality of fibers, wires or other fine porosity tubes forming a capillary bundle. The fibres or threads may be substantially aligned to convey the liquid aerosol-forming substrate towards the transport material. Alternatively, the retaining material may comprise a sponge-like or foam-like material. The retaining material may comprise any suitable material or combination of materials. Examples of suitable materials include sponges or foams, ceramic or graphite based materials in the form of fibers or sintered powders, foamed metal or plastic materials, fibrous materials (e.g., spun or extruded fibers such as cellulose acetate, polyester, bonded polyolefins, polyethylene, polypropylene fibers, nylon fibers, ceramic fibers), and combinations thereof. In one exemplary embodiment, the retention material comprises High Density Polyethylene (HDPE) or polyethylene terephthalate (PET). The high retention material may have superior wicking properties compared to the transport material such that it retains more liquid per unit volume than the transport material. Further, the thermal decomposition temperature of the transport material may be higher than the high retention material.

The cartridge may further comprise a transport material arranged to deliver the aerosol-forming substrate to the heating element. The transfer material may be in the shape of a disc. Such discs can be conveniently manufactured by stamping out a sheet of material. However, any other suitable shape may be used, such as square, rectangular, elliptical, oval, or another curved or polygonal or irregular shape. The thickness of the transmission material may be less than the length or width or diameter of the transmission material. Any suitable aspect ratio of length or width or diameter to thickness may be used. The aspect ratio of the length or width or diameter of the transmission material to the thickness of the transmission material may be greater than 3: 1.

alternatively, the transmission material may be in the shape of a hollow tube or cylinder according to a hollow tubular or cylindrical heating element. The hollow tubular or cylindrical transfer material may be formed by any suitable method, such as, for example, rolling a sheet of material. The inner diameter of the tube or cylinder transporting the material may be greater than the outer diameter of the hollow tubular or cylindrical heater.

The transfer material may have a first surface facing the high retention material and an opposite second surface facing the heating element. In a preferred embodiment, the second surface of the transfer material is in contact with a heater. If the heater has a planar surface, the second surface may be planar and may be in contact with the planar surface of the heater. If the heater has a contoured surface, the second surface may have a contour that follows the contoured surface of the heater and is in contact with the contoured surface of the heater. For example, if the heater has a convex dome-shaped surface, the second surface of the transmission material may follow the dome-shape. Such shapes may be added to the transfer material or may be a byproduct of the manufacture of the transfer material. The first surface and the second surface correspond to an outer surface and an inner surface of the hollow cylindrical transmission material, respectively. The heating element (whether in a cartridge containing the transfer material or in a device configured to receive a capsule containing the transfer material) may also have a residual arcuate shape due to some manufacturing process, and thus the surface of the transfer material may conform to the shape of the heating element.

The transport material may also comprise a capillary material. Capillary materials are materials that transport liquids through the material by capillary action. The transmission material may have a fibrous or porous structure. The transport material preferably comprises a bundle of capillary tubes. For example, the transmission material may comprise a plurality of fibers or wires or other fine pore tubes. The transport material is configured to transport fluid primarily in a direction orthogonal or perpendicular to the thickness direction of the transport material. The transport material may preferably comprise elongate fibres such that capillary action takes place in small spaces or microchannels between the fibres.

The transmission material may be made of a heat resistant material having a thermal decomposition temperature of at least 160 ℃ or higher, such as about 250 ℃ or higher. The transfer material may comprise fibres or threads of cotton or treated cotton, such as acetylated cotton. Other suitable materials may also be used, such as, for example, ceramic or graphite based fibrous materials or materials made by spinning, drawing or extruding fibers, such as glass fibers, cellulose acetate, or any suitable heat resistant polymer. The fibers of the transmission material may each have a thickness of between 10 μm and 40 μm, and more particularly between 15 μm and 30 μm. The transport material may have any suitable capillarity and porosity for use with liquids having different physical properties. The transport material may transport the liquid aerosol-forming substrate by capillary action. The liquid aerosol-forming substrate has physical properties including viscosity, surface tension, density, thermal conductivity, boiling point, vapour pressure, etc. which are tailored to facilitate transport of the liquid aerosol-forming substrate through the transport material by capillary action.

According to an aspect of the disclosure, the cartridge includes a barrier layer in the liquid flow passage. According to an aspect of the disclosure, the cartridge comprises a barrier layer between the liquid aerosol-forming substrate and the airflow path.

The term "layer" is used herein to refer to a barrier, which is a distinct layer, film or coating, which may be applied to the high retention material, the transport material, or both, or may be stacked between two materials.

The barrier layer may be impermeable or substantially impermeable to aqueous liquids below a threshold temperature and become reversibly permeable to liquids at or above the threshold temperature. In some embodiments, the barrier layer is hydrophobic below a threshold temperature. The barrier layer may reversibly penetrate liquid (e.g., become hydrophilic or create pores) in a temperature-dependent manner. For example, the material of the barrier layer may be selected such that the barrier layer becomes permeable to liquid (e.g., aqueous liquid) at or above a predetermined threshold temperature. The barrier layer may be impermeable below a threshold temperature and permeable above the threshold temperature. In some embodiments, the barrier layer comprises a gate or aperture that closes below a threshold temperature and opens above the threshold temperature. According to one embodiment, the barrier layer may be rendered permeable at or above a threshold temperature and may again be rendered impermeable if the temperature of the layer falls below the threshold temperature.

The permeability of the barrier layer may be determined by assessing the penetration of a liquid aerosol-forming substrate (e.g. e-liquid) through the barrier. Two milliliters of liquid aerosol-forming substrate (based on different ratios of VG/PG, as well as on pure PG and on pure VG) were placed on the top surface of the film at ambient temperature (0 ℃ to 50 ℃) and at a relative humidity between 25% and 90%. The amount of liquid remaining on the top surface is monitored. A membrane will be considered impermeable if the rate of reduction of the amount of liquid on the top surface of the membrane is within 1 wt% in 1 week.

The predetermined threshold temperature may be selected such that when the heating element begins heating the transfer material and barrier layer upon activation of the system, the barrier layer becomes permeable, allowing liquid to transfer from the high retention material or liquid storage portion. For example, in some embodiments, the heating element is heated to a temperature of about 200 ℃ and thermally conducts to the barrier layer (e.g., by conduction into and through the transport material). The heating element may heat the transmission material to a temperature of about 200 ℃, or a temperature of at least 150 ℃, at least 175 ℃, or at least 200 ℃. The heating element may heat the transport material to a temperature of up to 175 ℃, up to 200 ℃, up to 210 ℃, up to 220 ℃ or up to 240 ℃. The heating element may heat the barrier layer (directly or indirectly) to or above a predetermined threshold temperature. The predetermined threshold temperature may be 60 ℃ or higher, 70 ℃ or higher, 80 ℃ or higher, 90 ℃ or higher, or 100 ℃ or higher. The predetermined threshold temperature may be 200 ℃ or less, 180 ℃ or less, 150 ℃ or less, 130 ℃ or less, 120 ℃ or less, 105 ℃ or less, or 100 ℃ or less. The predetermined threshold temperature may be influenced by the selection of the material, configuration, size, and other qualities of the barrier layer.

Preferably, the barrier layer is made of a non-toxic material that produces non-toxic degradation products, or is made of a non-toxic material that produces non-toxic degradation products. Materials approved for medical applications or food packaging are preferred. For example, materials approved by the united states federal drug administration ("FDA") for medical applications (e.g., for drug delivery, sutures, adhesion barriers, etc.), for food packaging, or for medical applications and food packaging are considered suitable for use in barrier layers.

The material of the barrier layer may be selected to have a desired reversible barrier quality. For example, the barrier layer may include a material that forms a gate during or after formation of the barrier layer. The gate can be opened and closed in a temperature dependent manner by various mechanisms, including expansion, contraction, chain folding, and the like. For example, the gate can be formed from a temperature-reactive material that includes a covalently cross-linked reversible polymer (e.g., a cross-linked hydrogel) that exhibits expansion below a threshold temperature and contraction above the threshold temperature. The pores or gates in the barrier layer may have a size (e.g., diameter) of about 0.01 μm to about 0.1 μm, or at least 0.01 μm, at least 0.02 μm, or at least 0.05 μm, or at most 0.2 μm, at most 0.5 μm, or at most 1 μm.

One suitable group of materials for the barrier layer includes covalently cross-linked reversible polymers that exhibit a change in polymer-polymer or solvent-polymer (e.g., water-polymer) interaction due to a change in temperature. Gates of such materials can be made by blending functional graft polymers or block copolymers or microspheres with the film-forming material. Polymer systems exhibiting an inverted U-shaped phase transfer curve and an upper critical solution temperature ("UCST") within a suitable threshold temperature range are considered suitable for use in the barrier layer. The UCST and thus the threshold temperature can be adjusted by the selection or number of functional groups (e.g., amino groups) and/or the chemical structure of the polymer chain. Examples of suitable polymer systems include (allylurea-allylamine) copolymers having amino groups (PAU-Am) (e.g., PAU and azidophenyl-PAU or "AP-PAU") and poly (pentafluorophenyl acrylate). The threshold temperature of these reversible polymers may be 40 ℃ or higher, 50 ℃ or higher, or 60 ℃ or higher; or 100 ℃ or less, 90 ℃ or less, 80 ℃ or less, 70 ℃ or less, or 65 ℃ or less.

Another suitable gate-forming material for the barrier layer comprises adsorbed or surface grafted chains. Depending on the temperature, the surface grafted chains may be hydrophilic or hydrophobic. In such barrier layers, gates are formed on the membrane by grafting functional monomers ("grafted from") or functional polymers or microspheres ("grafted to") onto the active sites on the barrier layer membrane such that the grafted portions constitute linear or cross-linked polymers in the pores. The monomer may be grafted by chemical, radiation, free radical, UV-induced or plasma-induced grafting. The polymer and/or microsphere may be chemically bonded (e.g., covalently bonded) to the layer. Suitable film-forming materials for the barrier layer include polypropylene (PP), polyethylene terephthalate (PET), poly (ether sulfone) (PES), hollow fiber membranes, and polystyrene-b-poly (4-vinylpyridine) (PS-b-P4VP) diblock copolymer membranes. Suitable adsorbed or surface grafted chain materials (e.g., gate forming materials) include poly (N-isopropylacrylamide) (PNIPAAm; threshold temperature in the range of 30-35 deg.C); poly (2-ethyl-2-oxazoline) (PEOx; threshold temperature of about 60 ℃); poly (2-ethyl-2-oxazine) (PEOZI; threshold temperature of about 56 ℃); PEO-b-PPO block copolymer (threshold temperature about 80 ℃); and natural temperature sensitive polymers (approved by the FDA for biomedical applications) such as hydroxypropyl methylcellulose (HPMC; threshold temperature of about 69 ℃). The threshold temperature of the barrier layer prepared using the above film-forming and gate-forming materials may be 40 ℃ or higher, 50 ℃ or higher, or 60 ℃ or higher; or 100 ℃ or less, 90 ℃ or less, 80 ℃ or less, 70 ℃ or less, or 65 ℃ or less. The threshold temperature can be modified by varying the amount and type of hydrophilic monomer (e.g., increasing the threshold temperature by decreasing the amount). For example, in copolymerizing NIPAAm (N-isopropylacrylamide) with a hydrophilic monomer such as acrylamide, the threshold temperature will increase to about 45 ℃ when 18% acrylamide is incorporated into the polymer, and will decrease to about 10 ℃ when 40% hydrophobic N-t-butylacrylamide (N-tBAAm) is added to the polymer.

In one embodiment, the barrier is made from a modified membrane, wherein the membrane comprises polypropylene (PP), polyethylene terephthalate (PET), poly (ether sulfone) (PES), hollow fiber membrane, and polystyrene-b-poly (4-vinylpyridine) (PS-b-P4VP) diblock copolymer membrane. In one embodiment, the membrane is modified with a temperature reactive material. The temperature reactive material may include linear polymer chains, crosslinked hydrogel networks, microspheres, or a combination thereof. The temperature reactive material may include a covalently crosslinked reversible polymer comprising a (allylurea-allylamine) copolymer (PAU-Am), a poly (pentachlorophenyl acrylate), or a combination thereof. The temperature reactive material may include poly (N-isopropylacrylamide) (PNIPAAm), poly (2-ethyl-2-oxazoline) (PEOx), poly (2-ethyl-2-oxazine) (PEOZI), PEO-b-PPO block copolymer, hydroxypropyl methylcellulose (HPMC), or a combination thereof.

Combinations of materials may be used to tailor the threshold temperature for a given device.

Other aspects of the barrier layer material that may be varied to achieve a desired threshold temperature include monomer structure and selection, molecular weight, crystallinity of the polymer, thickness of the barrier layer, and the like. These same masses can also be used to adjust for permeability changes in the barrier layer. For example, it may be desirable for the barrier layer to become permeable at less than 2S, less than 1S, or less than 0.5S when the threshold temperature is reached. It may be desirable for the barrier layer to become permeable as soon as possible upon reaching the threshold temperature, and without a desired minimum time. In practice, however, the barrier layer may become permeable for 10ms or more, 50ms or more or 100ms or more. In some embodiments, the barrier layer becomes permeable for at least 10ms, at least 50ms, or at least 100ms, and for at most 0.5s, at most 1s, at most 2s, or at most 4 s.

The thickness of the barrier layer may be about 10 μm or more, about 20 μm or more, about 50 μm or more, or about 100 μm or more. The thickness of the barrier layer may be about 1000 μm or less, about 800 μm or less, about 500 μm or less, or about 300 μm or less.

In some preferred embodiments, the shelf life of a cartridge comprising a liquid aerosol-forming substrate in a high retention material, a transport material and a barrier layer separating the high retention material and the transport material is 4 months or more; 5 months or longer; 6 months or longer; 7 months or longer; or 8 months or longer. The shelf life of the cartridge may be up to 24 months, up to 18 months, or up to 12 months. The term "shelf life" is used herein to refer to the period of time in which a product (e.g., a liquid aerosol-forming substrate and/or a barrier layer) does not significantly degrade, become unusable, or is unacceptable (e.g., does not leak) to a consumer.

The cartridge of the present disclosure may be pre-loaded into an aerosol-generating device, or may be inserted into the device by a user. When the cartridge is disposed in the aerosol-generating device, the transport material is operatively coupled with the heating element such that the transport material can be heated by the heating element. The heating of the transfer material also heats the barrier layer and renders the barrier layer permeable to a liquid (e.g., an aqueous liquid). In embodiments where the cartridge does not include a transfer material, the heating element may directly heat the barrier layer. Once the barrier layer becomes permeable to liquid, liquid aerosol-forming substrate from the high retention material may be delivered (e.g. by capillary action) into the transport material and heated by the heating element. Cooling of the barrier layer may render the barrier layer again impermeable to liquid (e.g., aqueous liquid).

One or more air inlets may be formed in the housing of the cartridge or base unit to allow air to be drawn into the cartridge to entrain aerosol generated by heating of the aerosol-forming substrate. The aerosol-containing stream may then be directed through a passageway in the cartridge or cartridge to the mouth end of the device.

The base unit includes a housing and a power source disposed in the housing. The base unit may also include an electronic circuit disposed in the housing and electrically coupled to the power source. The base unit may include contacts external to, exposed via, or effectively formed by the housing such that when the base unit is connected with the cartridge, the contacts of the component are electrically coupled with the contacts of the cartridge. The contacts of the component are electrically coupled to the electronic circuit and the power source. Thus, when the component is connected to the cartridge, the heating element is electrically coupled to the power source and the circuit.

Preferably, the electronic circuitry is configured to control delivery of the aerosol generated by the heated substrate to a user. The control electronics may be provided in any suitable form and may, for example, comprise a controller or a memory and controller. The controller may include one or more of the following: an Application Specific Integrated Circuit (ASIC) state machine, a digital signal processor, gate array, microprocessor, or equivalent discrete or integrated logic circuitry. The control electronics may include a memory containing instructions that cause one or more components of the circuitry to carry out functions or aspects of the control circuitry. The functions attributed to the control circuitry in this disclosure may be implemented as one or more of software, firmware, and hardware.

The electronic circuitry may be configured to monitor the resistance of the heater element or one or more filaments of the heater heating element and to control the supply of power to the heating element in dependence on the resistance of the heating element or the one or more filaments. The electronic circuit may comprise a microprocessor, which may be a programmable microprocessor. The electronic circuit may be configured to regulate the power supply. Power may be supplied to the heater assembly in the form of current pulses.

The component containing the power source may contain a switch to activate the system. For example, the component may include a button that can be pressed to activate or optionally deactivate the system. Alternatively, the system may comprise a sensor configured to activate the system when the sensor senses an airflow caused by a user inhaling air through the mouthpiece.

The power source is typically a battery, but may comprise another form of charge storage device, such as a capacitor. The power source may be rechargeable.

The housing of the base unit is preferably a rigid housing. Any suitable material or combination of materials may be used to form the rigid housing. Examples of suitable materials include metals, alloys, plastics or composites containing one or more of these materials, or thermoplastics suitable for food or medical applications, such as polypropylene, Polyetheretherketone (PEEK), acrylonitrile butadiene styrene, and polyethylene.

The aerosol-generating system of the invention may comprise a hood disposable over at least the liquid supply system. For example, the shroud includes a distal opening configured to receive the cartridge. The cover may also extend over at least a portion of the evaporation unit where the system includes a separate evaporation unit, and may also extend over at least a portion of the base unit. The shroud may be releasably secured in position relative to at least the barrel. The cover may be connected to the cartridge or base unit in any suitable manner, such as a threaded engagement, a snap-fit engagement, an interference fit engagement, a magnetic engagement, or the like.

The lid or housing of the cartridge may form a mouthpiece defining a mouth end of the aerosol-generating system. Preferably, the mouthpiece is generally cylindrical and tapers inwardly towards the mouth end. The mouthpiece defines an open-ended mouth opening to allow aerosol generated by heating of the aerosol-forming substrate to exit the device.

The terms "distal", "upstream", "proximal" and "downstream" are used to describe the relative positions of components or parts of components of an aerosol-generating system. An aerosol-generating system according to the invention may have a proximal end and an opposite distal end, wherein in use aerosol exits the proximal end of the system for delivery to a user. The proximal end of the aerosol-generating article may also be referred to as the mouth end. In use, a user draws on the proximal end of the aerosol-generating system in order to inhale an aerosol generated by the aerosol-generating system. The terms upstream and downstream are relative to the direction of movement of the aerosol through the aerosol-generating system when a user draws on the proximal end. The shroud or housing cooperates with the cartridge to form one or more passages therebetween through which air can flow.

The shroud comprises an elongate housing which is preferably rigid. The housing may comprise any suitable material or combination of materials. Examples of suitable materials include metals, alloys, plastics or composites containing one or more of those materials, or thermoplastics suitable for food or pharmaceutical applications, such as polypropylene, Polyetheretherketone (PEEK) and polyethylene.

The aerosol-generating system according to the invention may have any suitable size when all components are connected. For example, the system may have a length from about 50mm to about 200 mm. Preferably, the system has a length of about 100mm to about 190 mm. More preferably, the system has a length of about 140mm to about 170 mm.

All scientific and technical terms used herein have the meanings commonly used in the art, unless otherwise indicated. The definitions provided herein are to facilitate understanding of certain terms used frequently herein.

As used herein, the singular forms "a", "an" and "the" encompass embodiments having plural referents, unless the content clearly dictates otherwise.

As used herein, the term "or" is generally employed to mean one or all of the listed elements or a combination of any two or more of the listed elements.

As used herein, "having," including, "" comprising, "and the like are used in their open sense and generally mean" including, but not limited to. It is understood that "consisting essentially of … …", "consisting of … …", and the like are included in the "comprising" and the like.

The words "preferred" and "preferably" refer to embodiments of the invention that may provide certain benefits under certain circumstances. However, other embodiments may also be preferred under the same or other circumstances. Furthermore, recitation of one or more preferred embodiments does not imply that other embodiments are not useful, and is not intended to exclude other embodiments from the scope of the disclosure, including the claims.

The term "substantially" as used herein has the same meaning as "significantly" and is understood to modify the term at least about 90%, at least about 95%, or at least about 98% prior. The term "non-substantially" as used herein has the same meaning as "not significantly" and is understood to have the opposite meaning as "substantially", i.e., modifying the term before no more than 10%, no more than 5%, or no more than 2%.

Drawings

Reference will now be made to the accompanying drawings, which depict one or more aspects described in the present disclosure. However, it should be understood that other aspects not depicted in the drawings fall within the scope and spirit of the present disclosure. Like numbers used in the figures refer to like parts, steps, etc. It should be understood, however, that the use of a number to refer to a component in a given figure is not intended to limit the component in another figure labeled with the same number. Additionally, the use of different numbers to refer to parts in different figures is not intended to indicate that the different numbered parts cannot be the same or similar to other numbered parts.

Figure 1 is a schematic diagram of an example of an aerosol-generating system.

Fig. 2 is a schematic diagram of a liquid supply system according to an embodiment.

Figure 3 is a schematic diagram of another example of an aerosol-generating system.

Fig. 4 is a schematic diagram of a portion of a liquid supply system according to an embodiment.

The schematic drawings are not necessarily drawn to scale and are presented for illustrative, non-limiting purposes.

Detailed Description

Referring now to fig. 1, an aerosol-generating system 1 comprises two main components: a cartridge 100 and a base unit 300. The cartridge 100 extends from a mouth end 101 to a connection end 115. The cartridge 100 is removably connected to a corresponding connection end 315 of the base unit 300. The base unit 300 includes a housing 305 in which a battery 310, control circuitry 320, and any associated electronic circuitry (e.g., electrical conductors and contacts extending through the housing) are disposed. The aerosol-generating system 1 may be portable and may have dimensions comparable to conventional smoking articles such as cigars or cigarettes.

The cartridge 100 includes a housing 105 that houses a heater assembly 120, and a liquid storage compartment 103 having a first portion 130 connected to a second portion 135. The liquid aerosol-forming substrate 131 is held in the liquid storage compartment. The first portion 130 of the liquid storage compartment 103 is in fluid communication with the second portion 135 of the liquid storage compartment 103 such that liquid in the first portion 130 can pass to the second portion 135 (see fig. 2). The second portion 135 includes the high retention material 136, the barrier layer 125, and the transfer material 124. The heater assembly 120 contacts the second portion 135 via the transmission material 124. In the illustrated embodiment, the heater assembly 120 includes a fluid permeable heating element.

The airflow passages 140, 145 extend from an air inlet 150 formed in one side of the housing 105, through the cartridge 100, through the heater assembly 120, and from the heater assembly 120 to a mouthpiece opening 110 formed at the mouth end 101 of the housing 105. The mouthpiece is arranged at the mouth end 101 of the cartridge 100 opposite the connection end 115.

In the exemplary embodiment shown, the components of cartridge 100 are arranged such that a first portion 130 of liquid storage compartment 103 is disposed between heater assembly 120 and mouth end 101, and a second portion 135 of liquid storage compartment 103 is positioned on an opposite side of heater assembly 120, adjacent to connection end 115. In other words, the heater assembly 120 is disposed between the two portions 130, 135 of the liquid storage compartment 103 and is arranged to receive liquid from the second portion 135 after the barrier layer 125 becomes permeable. The airflow passages 140, 145 pass through the heater assembly 120 and extend between the first and second portions 130, 135 of the liquid storage compartment 103.

The system is configured such that a user can draw or inhale on the mouthpiece opening 110 of the cartridge to draw aerosol from the device. When the system 1 is activated, the control circuit 320 controls the supply of power from the battery 310 to the cartridge 100. The control circuit 320 may include an airflow sensor (not shown) that may provide power to the heater assembly 120 when a user is detected by the airflow sensor to draw on the cartridge 100. Alternatively, the system 1 may be activated by pressing a button. When the system 1 is activated, the heater assembly 120 is activated, thereby heating the transfer material 124 and the barrier layer 125. Once the barrier layer 125 reaches its predetermined threshold temperature, the barrier layer 125 becomes liquid permeable (e.g. a gate in the barrier layer opens) allowing the liquid aerosol-forming substrate 131 to pass from the high retention material 136 onto the transport material 124. The heater assembly 120 heats the liquid aerosol-forming substrate 131 and generates a vapor that is entrained in the airflow through the airflow passage 140. The vapor cools within the airflow in the passageway 145 to form an aerosol, which is then inhaled through the mouthpiece opening 110 into the mouth of the user.

Fig. 2 is a schematic cross-section of an exemplary cartridge 100 according to an embodiment. Cartridge 100 has an outer housing 105 extending from a mouth end 101 to an opposite connection end 115 of mouth end 101. The outer housing 105 includes a mouthpiece 102 defining a mouthpiece opening 110. A liquid storage compartment 103 holding a liquid aerosol-forming substrate 131 is provided within the housing 105. The liquid storage compartment 103 has a first portion 130 and a second portion 135. The liquid storage compartment 103 may be further defined by an upper storage compartment housing 137, a heater mount 134, and an end cap 138. A heater assembly 120 including a fluid permeable heating element 122 is retained in a heater mount 134. The retaining material 136 and the transfer material 124, separated by the barrier layer 125, are disposed in the second portion 135 of the liquid storage compartment 103 such that the transfer material 124 abuts the heater assembly 120. The retaining material 136 is arranged to transfer liquid to the transfer material 124 when the barrier layer 125 is heated to its threshold temperature.

Liquid in the first portion 130 of the liquid storage compartment 103 may travel to the second portion 135 of the liquid storage compartment 103 through liquid channels 133 on either side of the heater assembly 120. In this example two channels are shown to provide a symmetrical structure, but only one channel is necessary. The channel 133 is a closed liquid flow path defined between the upper storage compartment housing 137 and the heater mount 134.

The fluid permeable heating element 122 is substantially planar and is disposed adjacent the transmission material 124 between the transmission material 124 and the airflow passage 140. A first surface of the transmission material 124 faces the barrier layer 125 and a second surface, opposite the first surface, is in contact with the fluid permeable heating element 122. Once the barrier layer 125 reaches its threshold temperature and becomes permeable to liquid (e.g., a gate in the barrier layer is opened), the first surface of the transfer material 124 may be in fluid communication with the high retention material 136.

The fluid permeable heating element 122 may form a bottom wall of the airflow passage 140. Surfaces of the heater mount 134 and the upper storage compartment housing 137 may form side walls and a top wall of the airflow passageway 140, respectively. A vertical portion (not shown) of the airflow passageway 145 extends through the first portion 130 of the liquid storage compartment towards the mouthpiece opening 110.

The arrangement of figure 2 is merely one non-limiting example of a cartridge for an aerosol-generating system. Other arrangements are possible. For example, the fluid permeable heating element, the transmission material, and the retaining material may be arranged in a different order without departing from aspects of the invention.

Figure 3 shows an alternative arrangement of the aerosol-generating system 2 comprising a tubular or cylindrical heater assembly 220 and a liquid storage compartment 203. Similar to the system shown in fig. 1, the aerosol-generating system 2 comprises two main components, a cartridge 200 and a base unit 300. The cartridge 200 extends from a mouth end 201 to a connection end 215. The cartridge 200 is removably connected to a corresponding connection end 315 of the base unit 300. The base unit 300 is shown in fig. 1. The aerosol-generating system 2 may be portable and may be of comparable size to conventional smoking articles such as cigars or cigarettes.

The cartridge 200 includes a housing 205 containing a heater assembly 220 and a liquid storage compartment 203. The heater assembly 220 includes a fluid permeable heating element 222. In the example shown in fig. 3, the heating element 222 and the liquid storage compartment 203 are cylindrical and coaxial such that the liquid storage compartment 203 at least partially surrounds the heating element 222. The liquid aerosol-forming substrate 131 is held in the liquid storage compartment 203.

The cartridge 200 further includes a high retention material 236, a barrier layer 225, and a transfer material 224. In the example shown, the high retention material 236 is disposed adjacent the liquid storage compartment 203, and the barrier layer 225 is disposed adjacent the high retention material 236 and between the high retention material 236 and the transfer material 224. Each of the elements shown may be cylindrical or tubular. Each element may be coaxial with each other.

Once the barrier layer 225 is made permeable, the heating element 222 is arranged to receive liquid from the liquid storage compartment 203 and the high retention material 236 via the transfer material 224.

The cartridge may alternatively be prepared without the liquid storage compartment 203, in which case the liquid aerosol-forming substrate 131 may be stored in the high retention material 236. In embodiments that do not comprise a liquid storage compartment 203, the amount of liquid aerosol-forming substrate 131, and thus the number of puffs available from the device, may be less than a device that comprises a liquid storage compartment 203.

The cartridge may alternatively be prepared without the transmission material 224, in which case the barrier layer 225 may be disposed adjacent or in close proximity to (e.g., in contact with) the heating element 222.

In some embodiments, the cartridge is prepared without the liquid storage compartment 203 and the transfer material 224.

The heating element 222 forms a cavity in its center to facilitate airflow. The airflow channels 240, 245 extend from an air inlet 250 formed on one side of the housing 205, through the cartridge 200, through the central cavity of the heating element 222, and to a mouthpiece opening 210 formed at the mouth end 201 of the housing 205. The mouthpiece may be disposed at the mouth end 201 of the cartridge 200 opposite the connection end 215.

The system 2 is configured to be used in a similar manner as explained for the system 1 of fig. 1 and 2.

Fig. 4 is a schematic view of a liquid storage unit 30 according to an aspect of the present invention. The liquid storage unit 30 may be housed, for example, within a cartridge 100, 200, which may be coupled with a base unit 300 of an aerosol-generating system 1, 2, such as those shown in fig. 1 and 3.

As shown in fig. 4, the liquid supply system 30 comprises a high retention material 136 comprising a liquid aerosol-forming substrate 131, and a transport material 124 arranged in contact with the heater assembly 120 of the aerosol-generating system 1. The high retention material 136 is coated on at least one side with a barrier layer 125 which is impermeable to the liquid aerosol-forming substrate 131 below the threshold temperature and which prevents the liquid aerosol-forming substrate 131 from reaching the transfer material 124 (step a). However, when heat is applied to the barrier layer 125 (step b), bringing its temperature to a predetermined threshold temperature (e.g., to a temperature of 60 ℃ or greater), the structure of the barrier layer 125 changes, causing the gates in the layer to open and allow liquid to transfer from the high retention material 136 to the transfer material 124 (step c).

Various modifications and alterations of this invention will become apparent to those skilled in the art without departing from the scope and spirit of this invention. While the invention has been described in connection with specific preferred embodiments, it should be understood that the invention as claimed should not be unduly limited to such specific embodiments. Indeed, various modifications of the described modes for carrying out the invention which are obvious to those skilled in mechanical, electrical and aerosol-generating article manufacture or related fields are intended to be within the scope of the following claims.