Patent Application
20150209530
The present invention relates to substrates for vaporizing and delivering an aerosol agent to a user. In exemplary embodiments, the invention is a substrate configured for use with an aerosol agent delivery device to vaporize and deliver an aerosol agent, for example a therapeutic drug in the form of an aerosol to a patient, or nicotine in the form of an aerosol to a smoker.
Therapeutic agents, and in particular drugs, are commonly delivered to a patient, via a pill, capsule, tablet or the like that is ingested orally and absorbed into the bloodstream. A therapeutic agent may also be introduced directly into the bloodstream via an intravenous solution. Therapeutic agents that are ingested orally and absorbed require a longer period of time before the effects of the agent are realized by the patient. Furthermore, therapeutic agents delivered to a patient via a pill, capsule, tablet or the like suffer from a loss of effectiveness due to hepatic metabolism. Although more effective, intravenous drug delivery is generally inconvenient for a patient that is not resident in a health care facility and administration of the therapeutic agent can be painful. Delivery of a therapeutic agent in the form of an aerosol by inhalation overcomes the disadvantages of both delivery methods, but has yet to gain widespread acceptance and use. One possible reason for the limited role of inhalation drug delivery despite its increased efficacy, convenience and painless administration is the lack of a suitable device that is relatively easy to use for portable, reliable and repeatable vaporization and delivery of a variety of different therapeutic agents in an aerosol form. Existing devices for vaporizing and delivering a therapeutic agent in the form of an aerosol are suitable for use with only a limited class of therapeutic drugs, such as drugs for the treatment of asthma. In addition, none of the existing aerosol agent delivery devices are sufficiently portable, reliable, repeatable and easy to use.
The adverse health risks associated with smoking cigarettes have been recognized for decades. It is estimated that at least seventy percent (70%) of smokers today desire to reduce the amount of cigarettes they smoke, or want to quit altogether. Despite the known risks, only about six percent (6%) of smokers report that they were able to quit smoking entirely. The low rate of success is believed to be due to the highly addictive nature of nicotine present in conventional cigarettes. Nicotine gum and nicotine patches for the delivery of nicotine without the harmful by products of tobacco combustion have been available for years. Nicotine gum and nicotine patches, however, have proven to be largely unsuccessful as smoking cessation articles due to their failure to satisfy the smoker's hand-to-mouth and inhalation urges. In the past few years, nicotine delivery devices in the form of combustion-free electronic cigarettes, also commonly referred to as “smokeless cigarettes,” “e-cigarettes.” “e-cigs” and “digital cigarettes,” have been developed and introduced to the consuming public.
Popular brands of electronic cigarettes include BLU ECIGS® offered by Lorillard Technologies, Inc. of Greensboro, N.C., VUSE® offered by Reynolds Innovations, Inc. of Winston-Salem, N.C., MARK 1O™ offered by Phillip Morris, Inc. of Richmond, Va., and NJOY® offered by NJOY, Inc. of Scottsdale, Ariz. Each of the aforementioned commercially available electronic cigarettes replicates the hand-to-mouth and inhalation experiences of a traditional tobacco cigarette desired by smokers. Electronic cigarettes also satisfy a smoker's craving for the addictive nicotine without exposing the smoker to the carcinogenic by-products produced by the combustion of tobacco and without exposing by-standers to harmful second-hand smoke. As a result, electronic cigarettes are credited with providing a healthier nicotine delivery option to smokers and a healthy environment to by-standers subjected to second-hand smoke by significantly reducing, and potentially eliminating, the harmful effects of the carcinogens present in the smoke that would otherwise be produced and dispersed by lighting and smoking a traditional tobacco cigarette.
Traditional tobacco cigarettes are made of a combustible material that is ignited with a flame to cause the tobacco to burn. Burning tobacco releases smoke containing nicotine that is inhaled by the smoker to deliver the nicotine to the lungs. Electronic cigarettes, on the other hand, heat a liquid, referred to as “e-liquid” or “liquid nicotine,” containing nicotine, and in some instances flavoring, to convert the liquid into an aerosol (commonly referred to as nicotine vapor or vape) that is inhaled by the smoker to deliver the nicotine to the lungs. Most of the current electronic cigarettes include a battery energy source, an atomizer and a hollow, re-fillable or expendable cartridge that contains the liquid nicotine. Due to the frequency required to re-fill or replace the cartridge, an advanced type of electronic cigarette has been developed that combines the atomizer and the cartridge into a single “cartomizer” electrically connected to the battery. Cartomizers allow for a greater period of time between re-fill and/or replacement. The vaporization process is initiated by the smoker inhaling on the cartridge or cartomizer, or alternatively, by the smoker depressing a manual switch that activates the atomizer or cartomizer. The atomizer heats the e-liquid to convert an aerosol forming agent, such as glycerin or propylene glycol, and the liquid nicotine into nicotine vapor in the form of an aerosol. The nicotine vapor is inhaled through a mouthpiece in fluid communication with the atomizer or cartomizer to deliver the nicotine to the lungs of the smoker in the form of an aerosol. The smoker then exhales the residual nicotine vapor in the form of cigarette smoke absent the harmful by-products of tobacco combustion.
Despite the reduced health risks, there remain certain disadvantages with the electronic cigarettes that are currently available. For example, the e-liquid contained within the cartridge or cartomizer typically contains a solution of propylene glycol, vegetable glycerin (VG), and/or polyethylene glycol 400 (PEG400) mixed with concentrated flavoring and a highly variable concentration of nicotine. However, the liquid nicotine solutions of certain electronic cigarettes have been found to still contain known cancer-causing agents, referred to as tobacco-specific nitrosamines (TSNAs), as well as tobacco-specific impurities, such as anabasine, myosmine, and β-nicotine. In fact, a recent study by the Food and Drug Administration (FDA) detected diethylene glycol, a poisonous and hygroscopic liquid commonly used in anti-freeze solutions, in the e-liquid of one brand of electronic cigarette, and measurable levels of nicotine in e-liquid cartridges that claimed to be nicotine-free. These findings are particularly disturbing since the cartridges and cartomizers of electronic cigarettes are inherently susceptible to leakage and/or breakage owing to their small size and relative fragility. As a result, the danger exists that a cartridge or cartomizer could leak or break, and thus cause a user to directly inhale a harmful dosage of the liquid nicotine solution without vaporization. It is also possible for a leaking e-liquid to damage the electronics and/or corrode a battery of an electronic nicotine delivery device. Furthermore, the glycerin or propylene glycol aerosol forming agent in the e-liquid is a combustible liquid, and therefore, could cause a fire if the e-liquid leaks and comes into contact with an ignition source.
Accordingly, an improved aerosol agent delivery device for vaporizing and delivering an aerosol agent, for example a therapeutic drug in the form of an aerosol to a patient, or nicotine in the form of an aerosol to a smoker, is need that is convenient, safe and easy to use. In particular, an aerosol agent delivery device is needed that is capable of vaporizing and delivering a wide variety of aerosol agents in a portable, reliable, repeatable and easy to use manner. An improved substrate is also needed for vaporizing and delivering an aerosol agent that overcomes the problems, disadvantages and deficiencies of conventional e-liquid cartridges and cartomizers. In particular, a substrate for vaporizing and delivering an aerosol agent is needed that is usable with a wide variety of aerosol agents, and further, does not pose a risk of delivering a harmful dosage of the aerosol agent to a user, damaging the electronics or energy source of an aerosol agent delivery device, or causing a fire in the event that an e-liquid leaks.
As used herein, the term “aerosol” is intended to include vapors, gases, fine particles, and the like, both visible and invisible, generated by a heat source acting upon a means for forming an aerosol in a manner consistent with the present invention. As so defined, the term “aerosol” specifically includes any pharmacologically or physiologically active agents, and any desired additives, such as an aerosol forming agent, irrespective of whether they produce a visible aerosol. As used herein, the term “in heat conducting relation” is intended to mean a physical arrangement of two or more components whereby heat is transferred by conduction or convection from a heat generating source (e.g., a heating element) to a thermally conductive component (e.g., a heat conductor or a substrate) substantially throughout the heat generating period of the heat source. A heat conducting relation can be achieved by locating the components in fluid communication, direct physical contact or in close proximity to one another during operation of the heat source.
To achieve the foregoing and other objects, and in accordance with the purposes of the invention as broadly described herein, the present invention provides devices for vaporizing and delivering an agent in the form of an aerosol, referred to herein as “an aerosol agent,” as well as substrates configured for use with an aerosol agent delivery device. Exemplary embodiments of aerosol agent delivery devices are shown and described herein that are portable, effective, convenient, and relatively easy to use to reliably and repeatedly vaporize and deliver a wide variety of aerosol agents, for example a therapeutic drug to a patient, or nicotine to a smoker. Exemplary embodiments of substrates configured for use with an aerosol agent delivery device to vaporize and deliver an aerosol agent to a user are also shown and described herein. The improved substrates eliminate the inconvenience and safety concerns associated with e-liquid cartridges and cartomizers for conventional electronic cigarettes that may break and/or leak.
In one aspect, the invention is embodied by a handheld, portable torch for vaporizing an aerosol agent and delivering the aerosol agent to a user. By way of example and not limitation, the handheld torch may be used to vaporize and deliver a therapeutic drug in the form of an aerosol to a patient, or alternatively, nicotine in the form of an aerosol to a smoker. Broadly, the torch includes a heat generator operably coupled with a heat conductor defining a heat conducting chamber, and a generally hollow substrate holder operably coupled with the heat conducting chamber. The heat conductor has a first opening for receiving a heating element of the heat generator and for communicating heat generated by the heat generator to the heat conducting chamber. The heat conductor has a second opening for receiving an end of the substrate holder in heat conducting relation with the heat conducting chamber. The heat conductor has a third opening for allowing ambient air to be drawn through the heat conductor and the substrate holder when a user inhales on an opposite open end of the substrate holder. The heat generator is activated to ignite the heating element and thereby generate heat within the heat conductor that is communicated into the heat conducting chamber. The heat within the heat conducting chamber is conducted to a substrate disposed within the substrate holder that supports at least the aerosol agent and an aerosol forming agent. The conducted heat vaporizes the aerosol agent from the substrate to form an aerosol that is available along with ambient air to be inhaled by the user through the open end of the substrate holder.
The heating element of the heat generator of the hand-held torch utilizes a fuel source consisting essentially of a combustible liquefied gas to generate heat. The combustible liquefied gas preferably is selected from liquefied petroleum gas (LPG or LP-gas), propane, propylene, butylenes, butane, isobutene, methyl propane and n-butane. The substrate may be any heat absorbing material that is non-combustible at the temperature of the heat conducted to the substrate. By way of example and not limitation, the substrate may be formed of a semi-porous cellulose paper material or a finely woven wire mesh material having the aerosol agent and the aerosol forming agent applied to the substrate material. The aerosol forming agent is a polyol preferably selected from glycerin, glycerol, propylene glycol, 1,3-butylene glycol, triethylene glycol, glycryl esters, such as triacetin, propylene carbonate, and mixtures thereof. The aerosol agent may be a therapeutic drug in the form of a heat stable pharmaceutical having less than about 10% alteration and/or degradation under normal transport and storage conditions for treatment of a patient. Alternatively, the aerosol agent may be nicotine for inhalation by a smoker.
In another aspect, the invention is embodied by a handheld, portable, battery-powered aerosol agent delivery device for vaporizing an aerosol agent and delivering the aerosol agent to a user. By way of example and not limitation, the aerosol agent delivery device may be used to vaporize and deliver a therapeutic drug in the form of an aerosol to a patient, or alternatively, nicotine in the form of an aerosol to a smoker. Broadly, the aerosol agent delivery device includes a heat generator operably coupled in heat conducting relation with a generally hollow substrate holder. The substrate holder includes an end that is inserted into the heat generator in fluid communication with the ambient air and an opposite open end configured for use by a user to inhale the aerosol agent along with the ambient air. The heat generator includes a heating element disposed about the substrate holder and having an electrical connection with a battery. The heating element generates heat when electrically connected to the battery by a switch. Heat from the heating element is conducted to a substrate disposed within the substrate holder that supports at least the aerosol agent and an aerosol forming agent. The heat vaporizes the aerosol agent from the substrate to form an aerosol that is available to be inhaled by the user along with the ambient air through the open end of the substrate holder.
If desired, the aerosol agent delivery device may further include an auxiliary heat generator positioned adjacent the substrate disposed within the substrate holder. The auxiliary heat generator includes a generally hollow housing having an open end in fluid communication with the ambient air and an opposite end that is partially closed by an auxiliary heating element. The auxiliary heating element is electrically connected to the battery of the heat generator to produce an electrical current therethrough. Accordingly, the auxiliary heating element generates heat when electrically connected to the battery by the switch of the heat generator. Heat from the auxiliary heating element is conducted to the substrate disposed within the substrate holder adjacent the auxiliary heat generator that supports at least the aerosol agent and the aerosol forming agent. The heat generated by the auxiliary heating element, either alone or in combination with the heat generated by the heating element of the heat generator and likewise conducted to the substrate, vaporizes the aerosol agent from the substrate to form an aerosol that is available to be inhaled by the user along with the ambient air through the open end of the substrate holder.
In yet another aspect, the invention is embodied by a substrate configured for use with an aerosol agent delivery device to vaporize and deliver an aerosol agent to a user. The substrate includes a carrier made of a non-combustible and thermally conductive material, and a paste that is applied onto at least one surface of the carrier and dried. The paste comprises an aerosol agent and an aerosol forming agent, and the aerosol agent delivery device is operable for heating the substrate to vaporize the aerosol agent and the aerosol forming agent from the paste and to deliver the aerosol agent to the user in the form of an aerosol. In an exemplary embodiment, the carrier is made of a solid aluminum sheet metal or aluminum foil, or alternatively, is made of a perforated or expanded aluminum sheet metal or aluminum foil. The aerosol agent may be a therapeutic drug or nicotine, and further may be derived from an organic plant material. The paste may further include a binder material that acts to hold the paste together and serves to adhere the paste to the surface of the carrier. In an exemplary embodiment, the binder material is a hydrocolloid or a starch. The paste may further include an inorganic, inert filler material, such as calcium carbonate, aluminum oxide, alumina or carbon.
In yet another aspect, the invention is embodied by a viscous, semi-liquid paste for a substrate of an aerosol agent delivery device. The paste consists of a mixture of an aerosol agent, an aerosol forming agent and a binder material. The aerosol agent may be a therapeutic drug or nicotine, and further may be an organic plant material. The aerosol forming agent may be glycerin, vegetable glycerin (VG), propylene glycol, polyethylene glycol or mixtures thereof. The binder material holds the paste together and adheres the paste to a surface of a carrier. In an exemplary embodiment, the binder material is a hydrocolloid or a starch. The amount of the binder material in the mixture by weight ranges from about one-tenth percent (0.1%) to about ten percent (10%). The paste may further include an inorganic, inert filler material, such as calcium carbonate, aluminum oxide, alumina or carbon.
In yet another aspect, the invention is embodied by a paste for use with an aerosol agent deliver device to vaporize and deliver an aerosol agent to a user. The paste includes an aerosol agent, an aerosol forming agent and a binder material. A composition of the paste is formulated by hydrating the binder material in water and mixing the aerosol agent, the aerosol forming agent and the hydrated binder material together to form the paste. A predetermined amount by weight of the paste is then applied to at least one surface of a carrier and allowed to dry at room temperature until the paste is adhered to the carrier.
These and other features, aspects and advantages of the invention are better understood and appreciated when considered in light of the following detailed description of the invention with reference to the accompanying drawings.
The invention will be described more fully hereinafter with reference to the accompanying drawings in which one or more exemplary embodiments are shown. However, it is to be understood that the invention may be embodied in many different forms and should not be construed as limited to the exemplary embodiments set forth herein. Exemplary embodiments of the invention are provided herein so that this disclosure will fully and completely convey the broad scope of the invention and to enable one of ordinary skill in the art to make, use and practice the invention without undue experimentation. Like reference numbers in the description and accompanying drawing figures refer to the same or similar elements of the invention.
The exemplary embodiments provided herein show and describe devices for vaporizing and delivering an agent in the form of an aerosol, also referred to herein as an “aerosol agent,” to a user. As used herein, the term “aerosol” is intended to include vapors, dense gases, fine suspended particles, and the like, both visible and invisible. As so defined, “aerosol” specifically includes any pharmacologically or physiologically active agents, and any desired additives, such as an aerosol forming agent, irrespective of whether they produce a visible aerosol. Ideally, the aerosol has a density consistent with cigarette smoke and a small particle size on the order of about 0.2-3.0 microns. As used herein, the term “aerosol drug” refers to a therapeutic drug in the form of an aerosol available for delivery to a patient for use in inhalation therapy. Similarly, the term “aerosol nicotine” refers to nicotine in the form of an aerosol available for delivery to a smoker for use in smoking a combustion-free electronic cigarette, commonly referred to as a “smokeless cigarette,” “e-cigarette” or “e-cig.” The aerosol agent, and more specifically the aerosol drug or the aerosol nicotine, is preferably formed by an aerosol forming agent activated by heat generated by a heating element and conducted by a heat conductor. An aerosol agent delivery device for vaporizing and delivering an aerosol agent according to the invention provides a portable, effective, convenient, simple to use device for reliably and repeatedly vaporizing and delivering a wide variety of aerosol agents to a user. Such devices may be particularly useful for vaporizing and delivering a therapeutic drug in the form of an aerosol drug to a patient, or alternatively, nicotine in the form of aerosol nicotine to a smoker.
An environmental perspective view of an exemplary embodiment of a device 10 for vaporizing and delivering an aerosol agent according to the invention is shown in
The heat generator 20 may be any means for reliably and repeatedly generating a relatively clean source of heat. As shown and described herein, the heat generator 20 is a handheld, portable torch. In a particularly advantageous embodiment, the heat generator 20 is a modified form of a commercially available micro butane torch that is capable of generating a localized flame of up to about 2400° F. Examples of a suitable micro butane torch include the BernzOmatic Micro Flame Butane Torch, the Weller ML100 Magna-Lite Butane Torch, and the Blazer PT-4000 Pencil Butane Torch. The specific type, style and brand of the heat generator 20, however, are not considered essential to the invention. Regardless, an existing heat generator 20 that has proven to be suitable to achieve the primary objectives of the invention is a Weller® Portasol® PSI 100 handheld butane heat torch available from Cooper Tools of Apex, N.C. “Weller” is a registered trademark of Cooper Industries, Inc., and “Portasol” is a registered trademark of Oglesby and Butler Ltd.
As best shown in
As previously mentioned, the heat generator 20 may be any suitable device or apparatus for generating heat from a combustible liquefied gas. Preferably, however, the heat generator 20 is sufficiently small and lightweight to be held by the user in one or both hands during vaporization and delivery of the aerosol agent. The entire aerosol agent delivery device 10, including the heat generator 20, the heat conductor 30 and the substrate holder 40 should be small enough and sufficiently lightweight to be portable so that a user can conveniently transport and use the device in any location. Activating (for example, by depressing) the switch 25 causes the igniter 23 to ignite the heating element 24 and produce a high temperature open flame F (
The heat conductor 30 comprises a generally hollow housing 32 configured to be received within the recess 28 defined by the heat generator 20. Housing 32 defines a first opening, or recess, 31 at one end adapted for receiving the heat discharge end, or tip, 26 of the heat generator 20 such that the flame F is disposed within the recess 31 of the heat conductor 30 (
Housing 32 of heat conductor 30 further defines a second opening, or recess, 36 (
As shown, housing 32 of heat conductor 30 further defines a third opening, or recess, 38 opposite and in fluid (i.e. airflow) communication with recess 36. Recess 38 is also in fluid (i.e. airflow) communication with the ambient atmosphere such that ambient air can be drawn via recess 38 into and through the hollow substrate holder 40 that is aligned with the recess 38 when the end of the substrate holder 40 is positioned within the recess 36. Alternatively, recess 38 may be substituted by a plurality of smaller diameter openings each likewise being in fluid (i.e. airflow) communication with the ambient atmosphere and with recess 36 defined by housing 32. Regardless, it is important to note that the overall size (e.g. cross-sectional area and diameter) of the recess 38 is smaller than the overall size (e.g. cross-sectional area and diameter) of the recess 36 so that the end of the substrate holder 40 disposed within the recess 36 cannot pass through the recess 38 formed in the housing 32 of the heat conductor 30, as previously mentioned.
If desired, at least a portion of the housing 32 of the heat conductor 30 may be covered by a heat insulator 39, such as ceramic, insulating plastic or the like, so as to reduce the temperature generated by the heat generator 20 on the exterior surface of the housing. A known heat insulator 39 that can be employed in practicing the invention is a porous, resilient jacket formed from one or more layers of an insulating material. Alternatively, the heat insulator 39 could be an expanded metal jacket with or without perforations that is attached to the heat conductor 30 and may be spaced from the exterior surface of the housing 32 by an air gap. Preferably, the heat insulator 39 extends over substantially the entire outer periphery of the housing 32 of the heat conductor 30. Insulating materials which can be used in accordance with the present invention generally comprise inorganic or organic fibers such as those made out of glass, alumina, silica, vitreous materials, mineral wool, carbons, silicon, boron, organic polymers, cellulosics, and the like, including mixtures of these materials. Nonfibrous insulating materials, such as silica aero gel, pearlite, glass, and the like, formed in mats, strips or other shapes can also be used. Preferred insulating materials should have a softening temperature below about 650° C. and should not burn, char or decompose during use. Preferred insulating materials for the heat conductor 30 (and similarly the housing 22 of the heat generator 20) include ceramic fibers, such as glass fibers available from the Manning Paper Company of Troy, N.Y., under the commercial designations Manniglas 1000 and Manniglas 1200.
As shown, substrate holder 40 comprises an elongate, cylindrical, generally hollow aerosol delivery tube 42 having an end configured to be received within the recess 36 formed in the heat conductor 30. As previously mentioned, the end of the substrate holder 40 preferably engages the recess 36 in an interference fit so that the substrate holder and the heat conductor 30 are securely attached to one another during use. Alternatively, the end of the substrate holder 40 and the recess 36 may be provided with a spiral groove and cooperating thread, a light adhesive or any other means suitable for removably securing the end of the substrate holder to the housing 32 of the heat conductor 30. As shown herein, substrate holder 40 further comprises an annular heat sink 44 adjacent and circumferentially disposed about the end of the aerosol delivery tube 42 that is inserted into the recess 36 of the heat conductor 30. The heat sink 44 is made of any solid or semi-porous, non-combustible, thermally conductive material suitable for transferring heat from the annular heat conducting chamber 34 into a substrate 45 (FIG. 4) disposed within the substrate holder 40. By way of example and not limitation, the heat sink 44 may be a relatively thin, annular ring made of a thermally conductive metal or an impervious silicon or ceramic. Alternatively, the heat sink 44 may be a somewhat thicker ring formed from a cellulose material. In other instances, the heat sink 44 may be a finely woven wire mesh or perforated metal ring. Typically, however, the selection of the thermal conductivity, porosity, thickness and material of the heat sink 44 will be determined by the volatility of the aerosol agent and the aerosol forming agent utilized with the device 10.
Regardless, the heat sink 44 is operable to transfer the heat generated by the heat generator 20 and communicated to the annular heat conducting chamber 34 by the heat conductor 30 to the substrate 45 disposed within the substrate holder 40. The heat sink 44 is in heat conducting relation with the annular heat conducting chamber 34 and with the substrate 45 to transfer heat from the heat conducting chamber to the substrate by conduction or convection means readily understood and appreciated by those having ordinary skill in the art. In some instances, the heat sink 44 is further operable to support the substrate 45 within the substrate holder 40. By way of example and not limitation, the heat sink 44 is a non-combustible, thermally conductive metal ring that is in direct physical contact with the inner wall of the housing 32 that defines the annular heat conducting chamber 34. As a result, heat generated by the heating element 24 of the heat generator 20 and communicated to the annular heat conducting chamber 34 of the heat conductor 30 is transferred through the inner wall of the housing 32 into the heat sink 44, and subsequently transferred from the heat sink into the substrate 45.
As best shown in
The substrate 45 may have any desired size and shape sufficient to contain at least a single dosage amount of the aerosol agent and enough aerosol forming agent to volatilize (i.e. vaporize) the aerosol agent in the form of an aerosol. In an advantageous embodiment, the substrate 45 is generally cylindrical and formed from a cellulose-based paper material suitable for low temperature vaporization and aerosol formation at temperatures below the decomposition threshold of cellulose. By way of example and not limitation, the substrate 45 may be a semi-porous cellulose paper of the type commercially available from EMI Specialty Papers, Inc. of Redding, Conn. The cellulose paper is impregnated with a liquid mixture of the aerosol agent and the aerosol forming agent, or alternatively, the liquid mixture is deposited on the cellulose paper and absorbed. In another advantageous embodiment, the substrate 45 is made of a metal wire material formed as a finely woven wire mesh comprising one or more layers of wire mesh weaves. An example of such a substrate 45 is a metal filter available from G. BOPP USA, Inc. of Hopewell Junction, N.Y., commercially known as Twilled Dutch Weave Wire Cloth having a 510×3600 warp to weft weave with a warp wire diameter of about 0.025 mm and a weft wire diameter of about 0.015 mm. The preferred BOPP Twilled Dutch Weave Wire Cloth has a nominal filter rating of less than about 1 micron and an absolute filter rating of between about 5 and about 6 microns. The Twilled Dutch Weave Wire Cloth provides extremely small openings to maximize heat conduction and convection, while increasing the surface area available for deposition of the aerosol agent and the aerosol forming agent by as much as 8-fold. The specific weave and warp/weft wire diameter of the metal filter cloth, however, is determined by the optimum delivery characteristics of a particular aerosol agent, and in particular, the boiling point, vaporization rate and aerosol formability of the combination aerosol agent and aerosol forming agent.
Regardless of the material, the outer periphery of substrate 45 is preferably in direct contact with the annular heat sink 44 to provide a heat transfer relation between the heat conductor 30 and the substrate containing the aerosol agent and the aerosol forming agent. Thus, heat transfer to the substrate 45 and the resultant production of the aerosol agent for delivery to the user in the form of an aerosol is maximized. Because the aerosol agent and the aerosol forming agent are physically separated from the heating element 24 of the heat generator 20 by the annular heat conducting chamber 34 and the annular heat sink 44, the agents are exposed to a lower temperature than the open flame F generated by the heating element within the recess 31 of the heat conductor 30. Accordingly, the possibility of thermal degradation of the aerosol agent is unlikely.
As previously described, the aerosol agent and the aerosol forming agent are deposited onto the substrate 45 so that the aerosol forming agent can subsequently volatilize the aerosol agent in the form of an inhalable aerosol, or vapor, when heat is applied to the substrate. The aerosol agent and the aerosol forming agent are preferably combined into an admixed solution that is impregnated into or deposited onto the substrate 45. Regardless, the admixed solution may be applied to the substrate 45 in any convenient and suitable manner using any conventional means or process. By way of example and not limitation, the admixed solution may be applied to the substrate 45 by coating, spraying, brushing, dipping, vapor deposition, electrostatic deposition, chemical deposition, or the like such that the admixed solution forms a relatively thin film on the substrate consisting essentially of the aerosol agent and the aerosol forming agent. The aerosol agent may be any thermally stable, non-combustible agent, for example a therapeutic drug or nicotine, capable of being aerosolized and delivered to a user for vapor inhalation. The aerosol forming agent may be any thermally stable, inert aerosol former and/or carrier that is capable of volatilizing the aerosol agent and forming a vapor suitable for delivery to a user of an aerosol agent delivery device according to the present invention. Aerosol forming agents useful in the present invention are capable of forming an aerosol at the temperatures present in the heat conducting chamber 34, transferred to the heat sink 44 and subsequently transferred into the substrate 45 when heat is generated by the heating element 24. Such agents preferably are composed of carbon, hydrogen and oxygen, but they can include other elements and/or compounds.
The aerosol forming agent can be in solid, semisolid, or liquid form. Substances having these characteristics include polyhydric alcohols, such as glycerin and propylene glycol, as well as aliphatic esters of mono-, di-, or poly-carboxylic acids, such as methyl stearate, dimethyl dodecandioate, dimethyl tetradecandioate, and others. Preferably, the aerosol forming agent is a polyhydric alcohol, or a mixture of polyhydric alcohols. By way of example, and without limitation, preferred aerosol formers include glycerin, glycerol, propylene glycol, 1,3-butylene glycol, triethylene glycol, glycerol esters, propylene carbonate, and mixtures thereof. As much as possible of the aerosol agent and the aerosol forming agent carried on the substrate 45 should be delivered to the user. Preferably, above about 50 weight percent, more preferably above about 80 weight percent, and most preferably above about 90 weight percent of the admixed solution is delivered to the user. The substrate 45 containing the admixed solution of the aerosol agent and the aerosol forming agent may be provided to the user separately from the device 10 as single-dose unit of the aerosol agent, for example a single-dose of a therapeutic aerosol drug to a patient, or alternatively, a single-dose of aerosol nicotine to a smoker. In addition, a plurality of substrates 45 may be provided to the user in the commonly used packaging commercially known as a “blister pack” with each substrate vacuum packaged, sealed and individually removable for insertion into the substrate holder 40 before the substrate holder is inserted into the recess 36 of the heat conductor 30.
A perspective view of another exemplary embodiment of a device 50 for vaporizing and delivering an aerosol agent according to the invention is shown in
The receiver 62A may be a structural extension of the housing 62 of the heat generator 60. Alternatively, the receiver 62A may be a separate cylindrical component that is permanently secured within a suitably sized and shaped recess formed in the housing 62. Regardless, receiver 62A defines an open end configured for receiving an end of the substrate holder 40 therein. As previously mentioned, one end of the aerosol delivery tube 42 of the substrate holder 40 is removably engaged with the open end of the receiver 62A of the heat generator 60. By way of example and not limitation, the end of the aerosol delivery tube 42 may engage the open end of the receiver 62A in a slight interference fit. Alternatively, the substrate holder 40 may be secured to the receiver 62A of the heat generator 60 by a tapered press fit, a temporary adhesive, a spiral groove and cooperating thread, or the like. As shown in
As previously mentioned, and as illustrated in
The substrate holder 80 is inserted into the receiver 62A of the housing 62 of heat generator 60 and secured in a suitable manner previously described. Similar to the substrate holder 40 discussed hereinabove, substrate holder 80 comprises an aerosol delivery tube 82 and a substrate 85 containing the aerosol agent and the aerosol forming agent. The auxiliary heating element 74 is located within receiver 62A adjacent to and in close proximity to the substrate 85. Thus, substrate 85 is simultaneously heated by both the heating element 68 of the heat generator 60 and the auxiliary heating element 74 of the auxiliary heat generator 70 when a user activates switch 65 (for example by depressing the switch). Heating the substrate 85, and more particularly, the aerosol agent and the aerosol forming agent applied to the substrate 85, causes the aerosol agent to be vaporized and made available to the aerosol delivery tube 82. As shown herein, the substrate holder 80 is provided with a longitudinally extending hole 86 that is axially aligned with the recess 76 formed in the hollow housing 72 of the auxiliary heat generator 70 and the recess 66 formed in the housing 62 of the heat generator 60 and in fluid communication with the ambient atmosphere. Accordingly, the aerosol agent is delivered to a user in the form of an aerosol when the user draws ambient air from the surrounding atmosphere through the recess 66, the recess 76, the substrate 85, and the hole 86 provided in the substrate holder 80. If desired, substrate 85 may be provided with a longitudinally extending through hole that is axially aligned with hole 86 of substrate holder 80 in the manner previously described with reference to hole 46 formed through substrate 45 of substrate holder 40. As will be readily appreciated, the substrate holder 80 including substrate 85 is intended to be removable from the receiver 62A of heat generator 60 for convenient storage and transport, as well as for the purpose of replacing an expendable substrate. Accordingly, substrate holder 80 including substrate 85 may be intended for a single use (i.e. disposable), and replaceable with a new substrate holder 80 including a new substrate 85 having an aerosol agent and an aerosol forming agent applied thereto for each use by a patient or smoker.
The aerosol agent delivery devices 10, 50 shown and described herein are each designed to deliver a wide variety of aerosol agents to a user, for example a therapeutic drug in the form of an aerosol (i.e., aerosol drug) to a patient for inhalation therapy, or nicotine in the form or an aerosol (i.e., aerosol nicotine) to a smoker. Regardless, the aerosol agent is provided to the user in an effective, yet convenient, portable and simple to use device for repeatedly and reliably vaporizing and delivering the aerosol agent. The aerosol delivered to the user consists essentially of air, the aerosol agent (e.g. aerosol drug, aerosol nicotine, etc.) and the aerosol forming agent. The aerosol may also contain any desired flavorant or inert additive for improving the taste, consistency or texture of the aerosol, thereby making the inhalation therapy more palatable to a patient or to a smoker. The aerosol should have no significant mutagenic activity as measured by the industry standard Ames test. An aerosol agent delivery device 10 according to the present invention, when used properly, should deliver very low levels of carbon monoxide, preferably less than about 1 mg total CO delivery over the life of the device, more preferably less than about 0.5 mg total CO delivery, and most preferably essentially no total CO delivery.
As shown and described in the foregoing exemplary embodiments, the aerosol agent may be deposited on a substrate 45, 85 comprising a cellulose-based material, an expanded starch-based material, a combination cellulose-based and expanded starch-based material, or a semi-porous finely woven wire mesh or screen. Each of the previously mentioned substrate materials allows the aerosol agent to be provided in the form of a solid formulation that is vaporized from the substrate and delivered to the user in the form of an aerosol for inhalation by the user. The construction of the substrates 45, 85 and the substrate materials previously described are particularly advantageous for use with the aerosol agent delivery devices 10, 50 shown and described herein to eliminate the inconvenient, potentially harmful and possibly dangerous liquid nicotine cartridges and cartomizers used with conventional electronic cigarettes. Nevertheless, the cellulose-based material or expanded starch-based material that may be utilized in the substrate 45, 85 is prone to heat degradation, commonly referred to as scorching, once the aerosol former is evolved. The finely woven wire mesh or screen is typically utilized in the substrate 45, 85 in instances that require an aerosol to be produced from an aerosol agent and an aerosol forming agent at a temperature that exceeds the degradation temperature of the cellulose-based material and the expanded starch-based material. However, the stainless steel wire mesh or screen is not able to support the amount of the aerosol agent and aerosol forming agent that can be supported by either the cellulose-based material or the expanded starch-based material. Thus, the present invention also provides a substrate configured for use with an aerosol agent delivery device that is not susceptible to heat degradation, combustion or corrosion, while supporting a sufficient amount of the aerosol agent and aerosol forming agent thereon. The present invention further provides substrates that can be readily adapted for use with different aerosol agent delivery devices and heating elements, including auxiliary heating elements, having various geometries.
The carrier portion 102 of substrate 100 is formed in the shape of a relatively thin, circular disc from a non-combustible, thermally conductive, non-toxic and non-off gassing material, such as metal, glass or ceramic. In a particularly advantageous exemplary embodiment, the carrier 102 of the disc substrate 100 is formed from a relatively thin sheet of aluminum or from aluminum foil. For example, carrier 102 may be cut, stamped or otherwise formed in the shape of a disc from aluminum sheet metal having a thickness of between about 0.002 inches and about 0.025 inches. Carrier 102 of the substrate 100 shown in
For the purpose of explanation and illustration, the paste portion 104 of disc substrate 100 shown in
Common examples of hydrocolloids suitable for use in formulations of paste 104 include agar, alginate, arabinoxylan, carrageenan, curdlan, gelatin, gellan, β-glucan, guar gum, gum arabic, locust bean gum, pectin, xanthan gum, methyl cellulose, carboxymethyl cellulose (CMC), sodium CMC, ethyl cellulose, ethyl methyl cellulose and hydroxypropyl cellulose. Common examples of commercialized starches suitable for use in formulations of paste 104 include cornstarch, tapioca, wheat, rice, potato starch (e.g., sweet potato starch), sago mung bean and Florida arrowroot. Functionalized starches that are also suitable for formulations of paste 104 include dextrin, acid-treated starch, alkaline-treated starch, bleached starch, oxidized starch, enzyme-treated starch, monostarch phosphate, distarch phosphate, phosphated distarch phosphate, acetylated distarch phosphate, starch acetate, acetylated distarch adipate, hydroxypropyl starch, hydroxypropyl distarch phosphate, hydroxypropyl distarch glycerol, starch sodium octenyl succinate and acetylated oxidized starch. Regardless, the binder material present in the formulation of the paste mixture typically ranges from only about one-tenth percent (0.1%) to about ten percent (10%). More particularly, the amount of the binder material ranges from about one-tenth percent (0.1%) to about five percent (5%), and still more particularly, from about one-half percent (0.5%) to about one percent (1.0%).
In addition to the hydrocolloid or starch binder material, paste 104 comprises at least an aerosol agent and an aerosol forming agent, also referred to herein as an aerosol former. As described hereinabove, the aerosol agent may be a therapeutic drug in the form of a heat stable pharmaceutical having less than about 10% alteration and/or degradation under normal transport and storage conditions for treatment of a patient. Alternatively, the aerosol agent may be nicotine evolved from tobacco oil for inhalation by a smoker. However, as will be described hereinafter, the aerosol agent may be evolved from an organic plant material, including tobacco, and may be used with or without an aerosol forming agent. As previously mentioned, the aerosol forming agent is a polyol preferably selected from glycerin, glycerol, propylene glycol, 1,3-butylene glycol, triethylene glycol, glyceryl esters, such as triacetin, propylene carbonate, and mixtures thereof. Specific examples of suitable aerosol forming agents include glycerin, vegetable glycerin (VG), propylene glycol and polyethylene glycol (e.g., PEG400). If desired, the paste 104 of substrate 100 may further comprise an inorganic, inert filler material and/or one or more flavoring additives.
As mentioned, the aerosol agent may be derived from an organic plant material comprising, for example, tobacco, coffee, tea, etc., in a whole, cut, chopped, ground or powder form. In still other embodiments, the organic plant material may comprise plant extracts, such as tobacco extract. An aerosol agent derived from organic plant material, for example ground tobacco powder or tobacco extract, can be used along with a binder material and an inert filler material with or without an aerosol former. However, an aerosol former will be desirable in many instances as a means of diluting the concentration of the aerosol agent delivered to the user. A particular advantage of utilizing a substrate comprising a paste is that a variety of different organic plant materials can be used as the base substance of the paste formulation. The inorganic inert filler material serves to hold the aerosol agent (e.g., therapeutic drug, nicotine, etc.) and the aerosol former in a dispersed and non-liquid form prior to vaporization and/or as a diluent. By way of example and not limitation, the filler material may comprise calcium carbonate, alumina (synthetically produced aluminum oxide), activated carbon powder, graphite powder, combinations thereof, and other similar inorganic materials that will not ignite or burn at the vaporization temperatures of the aerosol agent and aerosol forming agent.
Paste 104 may be applied onto at least one surface of the carrier 102 of substrate 100 in any convenient manner. By way of example and not limitation, the carrier 102 may be dipped into a solution of the paste 104, or the paste 104 may be brushed onto the carrier 102 of the substrate 100. In another suitable process, the paste 104 may be sputtered onto a surface of the carrier 102 or may be deposited thereon by means of electrostatic deposition. A particular process for applying the paste 104 to the carrier 102 may be preferred, for example, if the amount of the aerosol agent available to be vaporized and delivered to the user is controlled by the weight of the paste 104 applied to the carrier 102 of the substrate 100. If a larger mass of the paste 104 on the carrier 102 is desired, the dipping or brushing process may be most efficient and effective. On the other hand, if a smaller mass of the paste 104 on the carrier 102 is desired, the sputtering or deposition process may be more practical. Regardless of the application process, the hydrocolloid or starch component of the paste 104 acts as an adhesive binder that holds the viscous, semi-liquid paste to the surface of the carrier 102 of the substrate 100 until the composition dries and hardens. The relatively viscous mixture of the paste 104 adheres to the surface of the carrier 102 and subsequently dries as a solid composition on the surface of the carrier.
The choice of material selected for the carrier portion of the substrate can be important for its physical and chemical properties. With respect to substrates that must be formed in to a desired geometry, such as a cylinder or spiral cylinder, the material needs to be sufficiently formable, for example by molding, bending, rolling, etc., and/or mechanically shaped, for example by drilling grinding, boring, etc. Thus, a minimum predetermined fragility and/or crystallinity of the material may be required. Thermal capacity and thermal conductivity are other physical properties of the material that may be important to achieve a desired minimum amount of heat transfer from the heating element of the heat generator to the substrate to vaporize the aerosol agent. The surface properties of the material of the carrier of the substrate may also be important to hold a desired amount of the paste on the carrier. The material of the carrier should have a minimum degree of roughness, porousness and/or ability to adhere the paste to the carrier depending on the type and composition of the paste. By way of example, Teflon® would not be a suitable material for the carrier of the substrate because it has very low surface tension. The paste must be able to adhere to the surface of the carrier and/or fill any openings, pores or voids in the carrier of the substrate, and also remain in place on the carrier until and after the paste dries.
As previously mentioned, the paste composition comprises at least a binder material, an aerosol agent and an aerosol forming agent (aerosol former) to facilitate volatilization of the aerosol agent (e.g., aerosol drug or aerosol nicotine). The binder component holds the paste composition together and causes the paste composition to adhere to the carrier of the substrate. When the substrate is heated, the aerosol former forms an aerosol of the aerosol agent for delivery to the user. The paste composition may further comprise an inorganic, inert material that operates as an innocuous filler component having mass to provide bulk to the paste composition, and in some instances, acts as a heat transfer agent to evenly distribute heat generated by the heat generator and transferred to the substrate by the heating element and any heat conductor. At the temperature of vaporization, an aerosol is formed that includes the volatilized aerosol agent to be delivered to the user. The paste composition reduces in mass and volume to some extent during the heating and volatilization process. In particular, the paste composition loses the mass of the aerosol forming agent and the aerosol agent as the substrate is heated, but does not soften, melt or scorch, Once the mass of the aerosol former and the aerosol agent is lost, the paste composition hardens, leaving a residual solid mass on the carrier of the substrate. The entire paste composition does not volatilize. Instead, only the aerosol former carrying the aerosol agent and any by-product volatiles is volatilized and delivered to the user in the form of an aerosol. The heated binder, any residual aerosol former and any inorganic, inert filler material remain adhered to the carrier of the substrate.
In a preferred embodiment, a formulation of the paste composition comprises a mixture of a binder material, such as sodium carboxymethyl cellulose (NaCMC), an aerosol agent, such as a therapeutic drug or nicotine, and an aerosol forming agent (aerosol former), such as glycerin or propylene glycol. In a further embodiment, the formulation of the paste composition further comprises an inorganic, inert filler material, such as calcium carbonate, alumina or carbon. In another preferred embodiment, the aerosol agent component of the formulation is obtained from a ground organic plant material, such as finely ground tobacco, coffee, tea, etc. An exemplary embodiment of a method for formulating a paste composition for a substrate according to the present invention comprises fully hydrating the binder material in water and mixing together the aerosol agent, the aerosol former and any filler material to form a paste. A desired amount, typically determined by weight, of the paste is then applied to the carrier of the substrate in a convenient manner. The paste composition is then allowed to dry at room temperature until the paste is sufficiently adhered to the carrier of the substrate. In some instances, an aerosol former (e.g., glycerin, propylene glycol, etc.) and an aerosol agent (e.g., aerosol drug, aerosol nicotine, etc.) may be applied to the paste composition after formation of an inert material into the substrate. As previously mentioned, certain aerosol formers, such as glycerin and propylene glycol, are combustible liquids as used in e-liquid cartridges and cartomizers, and therefore, pose a risk of fire in the event that the e-liquid leaks and comes into contact with an ignition source. Formulations of a paste composition according to the present invention comprising a non-combustible, inert filler material, such as calcium carbonate, alumina, carbon, graphite, etc., absorb the combustible aerosol former and thereby greatly reduce any fire hazard.
Examples of formulations of the paste composition suitable for use with a substrate and an aerosol agent delivery device according to the present invention include:
The foregoing is a description of various exemplary embodiments of the present invention given for purposes of explanation and illustration only. Although various embodiments of aerosol agent delivery devices and substrates for vaporizing and delivering an aerosol agent to a user have been described herein with reference to the accompany drawing figures, other embodiments of the invention may exist or become later known that perform similar functions and/or achieve similar results. All such equivalents are within the spirit and scope of the present invention, and thus, are intended to fall within the broadest reasonable interpretation of the appended claims consistent with this specification.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 14053335 | Oct 2013 | US |
| Child | 14681816 | US |
