JPH0419867B2 - - Google Patents

Abstract

A member is provided for conducting heat from a combustible fuel element to an 'aerosol' generator which includes aerosol-forming material. The conducting member is spaced from the lighting end of the fuel element by at least 5 mm., and can circumscribe both the fuel element and generator, at least partially. Alternatively, the conductor contacts the fuel element along less than approx. half its length, e.g. it is embedded within it. Pref. the fuel element has a length of less than approx. 30 mm and has a density of about 0.5 g/cc.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention provides an aerosol similar to tobacco smoke, preferably in the form of a cigarette, which has less incomplete combustion and less heat than a regular cigarette. The present invention relates to smoking articles having a significantly reduced content of decomposition products.

BACKGROUND OF THE INVENTION A variety of smoking articles have been proposed, particularly over the last few decades, but none have achieved commercial success.

Despite decades of interest and research, it has been found that conventional cigarettes can be produced without the significant amounts of incomplete combustion and thermal decomposition products found in conventional cigarettes. There is currently no smoking article on the market that provides a taste similar to that obtained by smoking a cigarette.

SUMMARY OF THE INVENTION The present invention provides smoking articles, preferably in the form of cigarettes, that utilize small dense combustible fuel elements in conjunction with a separate aerosol generating means containing one or more aerosol generating agents.

The aerosol generating means may be in a conductive heat exchange relationship with the fuel element and/or may include at least a portion of the fuel element in an elastic insulating jacket (also referred to as a "insulation layer") to reduce heat loss due to radiation. It is preferable to surround it. When the fuel element is ignited, it generates heat, which evaporates the aerosol generating agent within the aerosol generating means. This volatile material, like the smoke from a conventional cigarette, is drawn towards the mouth end of the smoking article and into the smoker's mouth during the smoker's inhalation action.

The smoking article of the present invention is capable of producing a significant amount of aerosol throughout its useful life and can provide the user with a sensation similar to smoking a cigarette. The aerosol produced by this aerosol generating means is produced with almost no deterioration due to heat, and moreover, the amount of incomplete combustion and thermal decomposition products generated is considerably smaller than that of conventional cigarettes. .

The small fuel elements used in the present invention are approximately
30 mm or less, preferably about 20 mm or less, e.g. at least about 0.5 g/g as measured by mercury displacement.
cc, preferably at least about 0.7 g/cc. The fuel element can be molded or extruded from ground or reconstituted tobacco material and/or tobacco substitutes and preferably includes combustible carbon. The fuel element is also preferably provided with one or more passages, preferably from five to nine, or from five to nine, for controlling heat transfer from the burning fuel element to the aerosol generating agent in the aerosol generating means. It is further preferable to provide more passages.

The aerosol generating means comprises an aerosol generating agent support or carrier (hereinafter also simply "support" or "carrier"), preferably made of a thermally stable material, carrying one or more aerosol generating agents. It is advantageous to have a

Conductive heat exchange between the fuel element and the aerosol generating means is accomplished by a metal conductor such as a metal conductor that contacts both the fuel element and the aerosol generating means and effectively conducts heat from the burning fuel element to the aerosol generating means. It is preferable to carry out this by providing a heat conductive member. The heat conductive member preferably surrounds and contacts at least part of the outer peripheral surfaces of the fuel element and the aerosol generating means, in order to avoid interference with ignition and combustion of the fuel element, and to avoid protrusion of the heat conductive member. To achieve this, it is preferred that the thermally conductive member be spaced or retracted from the tip of the fuel element, preferably at least about 3 mm, and more preferably at least about 5 mm. Preferably, a separate thermally conductive container or capsule for accommodating the aerosol generating agent and its support is provided as a thermally conductive member.

Furthermore, it is preferable to cover at least a portion of the fuel element with an elastic insulation jacket (also referred to as "insulation jacket" or "insulation layer"), for example made of insulation fibers. The insulation layer is at least 0.5mm
Preferably, it is a thick, elastic, non-combustible material. This layer of insulation serves to reduce radiative heat loss, assist in retaining and directing heat from the fuel element toward the aerosol generating means, and inhibit the fire-producing properties of the fuel. Preferably, the layer of insulation surrounds at least a portion of the fuel element and surrounds at least a portion of the aerosol generating means to mimic the feel of a conventional cigarette. The heat insulating material of the heat insulating material layer for the fuel element and the heat insulating material of the heat insulating material layer for the aerosol generating means may be the same material or may be different materials.

Since the fuel element is relatively short, its burning conical mass is always in close proximity to the aerosol generating means, thus maximizing heat transfer to the aerosol generating means, especially for multi-channel fuel elements, Embodiments that include a thermally conductive member and a layer of insulation maximize aerosol production. The small fuel element burns for approximately the same amount of time as a conventional cigarette,
and a relatively dense fuel material is used to provide sufficient thermal energy to generate the required amount of aerosol. Since the aerosol generating means is physically separate from the fuel element, it is exposed to considerably lower temperatures than if it were placed within the burning cone, reducing the risk of thermal deterioration of the aerosol generating agent. minimized.

Smoking articles of the present invention typically include a mouthpiece including an aerosol delivery means forming a longitudinal passageway for delivering the volatile substance, or aerosol, created by the aerosol generating means to the user. . Preferably, the mouthpiece includes an elastic outer member, such as a toroid of cellulose acetate, to mimic the feel of a conventional cigarette. Advantageously, the smoking article has the same overall dimensions as a conventional cigarette, so that the mouthpiece containing the aerosol delivery means (i.e. the aerosol delivery passageway) will typically be approximately 1/2 of the total length of the smoking article. /2 or longer. Alternatively, a smoking article consisting solely of the fuel element and the aerosol generating means may be constructed without incorporating a mouthpiece containing the aerosol delivery means and combined with a separate disposable or reusable mouthpiece. You may also use it.

The smoking articles of the present invention may also be supplemented with a charge of tobacco material that can be used to add tobacco flavor to the aerosol. The tobacco material charge can be inserted between the aerosol generating means and the mouthpiece. Preferably, a circular body or jacket of tobacco material is fitted onto the outer circumferential surface of the aerosol generating means. In that case, the tobacco jacket also acts as an insulator and helps mimic the flavor and feel of a conventional cigarette. The tobacco pack may be mixed with the aerosol generating agent or may be used as a support for the aerosol generating agent. Other substances, such as flavoring agents, can also be incorporated into the smoking article to flavor or otherwise modify the aerosol.

The smoking articles of the present invention typically use significantly less fuel on a volume, and preferably weight, basis than conventional cigarettes to generate the required aerosol. Also, the aerosol that is inhaled into the user's mouth has a low content of incomplete combustion and thermal decomposition products. This is because the aerosol created from the aerosol generating means is not thermally degraded and the pyrolysis products and , or the amount of products of incomplete combustion is
Even if the fuel element is made of tobacco wood or other cellulosic material, it is considerably less common than in conventional cigarettes.

"Aerosol" as used herein refers to vapor, gas, particles, etc. created when heat from a burning fuel element acts on the aerosol generating means or on substances present in other parts of the smoking article. (visible,
(whether invisible or not), especially components that look like smoke. In addition, the term "aerosol generating agent" as used herein refers to a volatile flavoring agent and/or a pharmacologically active agent (i.e., having a pharmacological effect), regardless of whether the aerosol generated is visible or not. Or it refers to a physiologically active drug (that is, it has a chemical effect such as making you feel refreshed).

"Conductive heat exchange relationship" refers to a physical configuration of the aerosol generating means and the fuel element arranged such that heat is transferred by conduction from the fuel element to the aerosol generating means throughout the combustion of the fuel element. The conductive heat exchange relationship involves transferring heat from the burning fuel element to the aerosol generating means by placing the aerosol generating means in contact with the fuel element and in close proximity to the combusting portion of the fuel element. It can be set by using a conductive member for. It is preferable to use the above two methods of conducting heat transfer by conduction in combination.

The term "insulating material layer" as used herein includes any material that primarily functions as a heat insulator. They are preferably non-combustible in use, but may also contain materials that melt in use, such as slow-flammable carbon and, in particular, low-temperature varieties of glass fibre. The insulation material is g-cal/(sec)( ^cm2 )(℃/
cm) in units of about 0.05 or less, preferably about 0.02 or less,
Most preferably it has a thermal conductivity of about 0.005 or less. (Hatsuku's Chemical Dictionary 34, 1969
4th edition and "Lang's Chemistry Handbook" 10,
272-274, 11th edition, 1973) The outer surface of the smoking article of the present invention can be wrapped with a paper wrapper over the entire length or any portion thereof.
In that case, the paper wrapper on the fuel end side must not flare up during combustion of the fuel element. It is also preferred that the paper wrapper has certain smoldering properties, resulting in a gray, cigarette-like ash. In a structure in which an insulating jacket is provided around the fuel element and a paper wrapper is wrapped around it, if the paper wrapper is made of a material that is completely destroyed by combustion by the heat from the fuel element, the surrounding Because airflow from the environment to the fuel element is not restricted, heat transfer from the fuel element to the aerosol generating means may be excessive. The present invention prevents this from happening by using a paper wrapper made of a material that will remain fully or partially unbroken when exposed to heat from the fuel element. In that case, the paper wrapper serves to restrict the air flow to the burning fuel element, thereby controlling the combustion temperature of the fuel element and the heat transfer to the aerosol generating means.

DESCRIPTION OF THE EMBODIMENTS The smoking article of one embodiment of the invention, shown in FIG. , an aerosol generating means 12 impinging thereon, and a mouthpiece 40. The mouthpiece 40 is connected to the aerosol feeding passage 1
8, an annular member 42 of elastic high-density cellulose acetate tow surrounding the plastic tube, and a low-efficiency cellulose acetate filter plug 45 abutting the annular member 42.
(Here, "low efficiency" refers to low efficiency as a filter for removing nicotine and tar.)
It consists of Filter plug 45 constitutes the mouth end of the smoking article. It is preferable to cover the filter plug 45 and the annular member 42 with a conventional plug wrapper 85, and further cover the plug wrapper 85 with a suction paper 86.

The fuel element 10 is extruded or molded from a mixture containing crushed tobacco material or reconstituted tobacco material and/or tobacco material substitute, and a small amount of combustible carbon. Preferably, it has several holes or passageways 16.
An example of a suitable hole arrangement is illustrated in FIG. 1A. These holes or passageways 16 are for controlling heat transfer from the combusting fuel element 10 to the aerosol generating agent within the aerosol generating means 12, as previously mentioned. The firing end of fuel element 10 may be tapered or otherwise reduced in diameter to facilitate ignition.

The aerosol generating means 12 includes a granular aerosol generating agent support (hereinafter also simply referred to as "support") 38 and/or compressed tobacco material (not shown).
, a metal container or metal capsule 90 surrounding it, and an aerosol generating agent impregnated or supported in one or both of the support and the tobacco material in some manner. The aerosol generating agent may be one or more aerosol generating agents such as triethylene glycol, propylene glycol, glycerin or mixtures thereof. In this embodiment, the metal capsule 90 of the aerosol generating means encloses the rear end of the fuel element 10 by 3 to 4 mm at a distance of about 6 to 12 mm from the ignition end. The rear portion of the capsule 90 is crimped in the shape of a lobe (eg, cloverleaf-shaped in cross section) as shown in FIG. 1B. A passageway 91 is formed in the center of the suction end of the capsule. Four additional passages 92 are drilled at the transition between the crimped and uncrimped portions of the capsule.
Alternatively, the rear portion of the capsule 90 may be rectangular or square in cross-section, rather than lobe-shaped, and may or may not include a peripheral passageway 92. Alternatively, a simple cylindrical capsule with a crimped suction end can be used.

The embodiments shown in FIGS. 1 and 2 include an elastic insulation jacket or layer surrounding the fuel element to isolate heat from the fuel element and concentrate the heat within the fuel element. It is. The insulating jacket is intended to prevent the cone-shaped lump of the burning fuel element from spreading to other parts, and to simulate the feel of a conventional cigarette.

In the embodiment of FIG. 1, the fuel element 10 is encased with an insulating jacket or layer 72, such as a low density glass fiber, and the aerosol generating means 12 is encased with a tobacco jacket or insulating layer 88. . The glass fibers used in this example were manufactured by Owens Corning Co., Toledo, Ohio, USA, such as Experimental Fiber 6432 and
Preferably, it has a softening temperature of about 650°C or less, such as 6437. The fiberglass jacket 72 and the tobacco jacket 88 are each made of
It is covered with a plug paper (wrapping paper) 85 such as 646. In addition, those plug ratupa 85,
85 is surrounded by a paper wrapper 89.

As mentioned below, the paper wrapper on the fuel end side must not flare up during combustion of the fuel element. It is also preferred that the paper wrapper has certain smoldering properties, resulting in a gray, cigarette-like ash. A heat insulating jacket 72 is provided around the fuel element 10 as shown in FIG.
In a structure in which a paper wrapper 89 is wrapped around the fuel element, if the paper wrapper 89 is made of a material that is completely destroyed by combustion by the heat from the fuel element, air flow from the surrounding environment to the fuel element is not limited, the heat transfer from the fuel element 10 to the aerosol generating means 12 may become excessive. The present invention prevents this from happening by using a paper wrapper made of a material that will remain fully or partially unbroken when exposed to heat from the fuel element. In the embodiment shown in FIG. 1, P878-16-2 manufactured by Kimberly-Clark is used as the paper wrapper 89 that covers the heat insulating layer 72 surrounding the fuel element 10. Kimberly-Clark Paper Lattspa, designated by the product number P878-16-2, is a paper whose material is constructed so that a portion of the paper remains intact during combustion. This paper wrapper 89 serves to restrict the flow of ambient air to the burning fuel element 10, thereby controlling the combustion temperature of the fuel element and the heat transfer to the aerosol generating means 12.

Alternatively, it is also possible to use a paper wrapper that covers the heat insulating material layer in the fuel element portion and is made of a material that will remain completely intact during combustion. According to the invention, as such a paper wrapper a non-porous paper which has been treated to be slightly porous, for example a non-flammable mica paper with a plurality of holes perforated therein, is used. Such paper reduces the combustion rate and temperature of the fuel element, thereby reducing CO/
CO ₂ ratio can be lowered. This paper controls the amount of heat delivered, especially during the intermediate suctions (ie, the fourth to sixth doses).

At the suction end of the tobacco material jacket 88 are the above-described cellulose acetate tow annular body 42, a plastic tube 44, a low-efficiency filter plug 45, a plug wrapper 85, and a cigarette paper wrapper 89.
A mouthpiece 40 including the following is attached. The mouthpiece 40 is connected to a jacketed fuel element/capsule assembly by an outer jacket layer of mouthpiece paper 86. As shown, the capsule end of plastic tube 44 is spaced from capsule 90. Therefore, passage 92
The hot vapor (aerosol) exiting through passes through the tobacco jacket 88 thereby vaporizing or extracting the volatile components in the tobacco within the jacket; The aerosol flows into the aerosol delivery passage 18 at the portion where the annular member 42 of the cellulose acetate tow collides with the annular member 42 of the tow.

In this embodiment having a low density insulating jacket 72, some air and gas will flow through the jacket 72 and into the tobacco jacket 88. Accordingly, a peripheral passageway 9 is provided in the capsule 90 for extracting tobacco flavor from the tobacco material jacket 88.
2 may not necessarily be provided.

In the embodiment of FIG. 2, the insulation jacket or layer 94 is comprised of tobacco or a mixture of tobacco and insulation fibers, such as fiberglass. In the illustrated example, the insulating jacket 94 extends slightly beyond the suction end of the metal container 96 of the aerosol generating means 12, but extends the entire length of the smoking article to the filter plug 45 at the mouth end. You may let them. In this embodiment, the container 96 has one or more longitudinal slots 99 in its outer circumferential surface.
(preferably two slots 180° apart)
It is preferable to provide an insulating jacket 94 which surrounds the aerosol generating means so that steam (aerosol) from the aerosol generating means is provided.
(the annular portion of the tobacco material) to extract the tobacco flavor and then flow into the passageway 18.

In this embodiment as well, the insulating jacket 94 is covered with a paper wrapper 89 made of the material described in connection with the embodiment of FIG. However, in this embodiment, the fuel element and the aerosol generating means are surrounded by a common heat insulating material layer, that is, a heat insulating jacket 94, and the heat insulating material layer is not wrapped in a plug wrapper as in the embodiment shown in FIG. 1, but is directly wrapped in a paper wrapper 89. to cover.

The aerosol generating means 12 includes a granular aerosol generating agent support 3 as in the embodiment shown in FIG.
8 and/or compressed tobacco material (not shown) and a metal container or metal capsule surrounding it 96
and an aerosol generator impregnated or supported in some manner on either or both of the support and the compressed tobacco material.

As shown, the tobacco leaves at the end of the insulating jacket 94 on the fuel element side are compressed.
The insulating jacket 94 reduces air flow through the tobacco material, thus preventing combustion of the tobacco material. Furthermore, the metal container 96 serves to extinguish the tobacco material in the insulating jacket 94 by functioning as a heat sink. This heat dissipation effect serves to extinguish the combustion of the tobacco material in the insulating jacket 94 surrounding the capsule or container 96, and also distributes heat evenly to the tobacco material in the insulating jacket 94 surrounding the capsule 96, thereby and assists in the release of tobacco flavor components.

Further, to assist in extinguishing the tobacco material in the insulating jacket 94, a portion 93 of the paper wrapper near the rear end of the fuel element is treated with a substance such as sodium silicate, so that the tobacco material in the insulating jacket 94 is removed from the fuel element 1.
It is desirable that combustion does not occur beyond the exposed end of zero to the inside. Alternatively, the tobacco material itself in the insulating jacket 94 surrounding the aerosol generating means may be treated with a flammability modifier to prevent combustion of the tobacco material.

In both of the embodiments shown in FIGS. 1 and 2 described above, when the fuel element 10 is ignited, it burns and generates heat for volatilizing the aerosol generating agent present in the aerosol generating means 12. The vaporized substance, or aerosol as used herein, is drawn towards the end of the mouth when inhaled by the user, and is inhaled into the user's mouth in the same way as smoke from a conventional cigarette. . Because the fuel element 10 is relatively short, the burning hot cone remains in close proximity to the aerosol generating means 12 throughout, thereby ensuring that the metal container of the aerosol generating means and any objects therein are kept close to the aerosol generating means 12. Maximizes heat transfer to the optionally disposed tobacco material, thereby maximizing aerosol and tobacco flavor production. Also, because the length of the fuel element 10 is short, there is no long unburned fuel section that acts as a heat sink as in conventional thermal aerosol articles. This short fuel element also has the effect of reducing the amount of incomplete combustion products or pyrolysis products, especially in embodiments where the fuel element contains carbon and/or has multiple passages. . The holes or passages provided in the fuel element also have the effect of increasing the heat transfer and thus the delivery rate of the aerosol by passing hot air to the aerosol generating means, especially during the inhalation action of the user.

Because the aerosol generating means is physically separate from the fuel element, it is exposed to significantly lower temperatures than if it were within the burning cone.
Therefore, the possibility of thermal deterioration of the aerosol generator and associated flavor deterioration is minimized. This arrangement also generates aerosol when inhaled by the user, but minimizes aerosol generation when not inhaled (ie, while the fuel is "smoldering"). In a preferred embodiment of the invention, passages in the insulation layer and/or the fuel element cooperate with the aerosol generating means to generate a significant amount of aerosol and optionally A system (article) capable of generating flavor is constructed. When the user inhales two or three doses after ignition, the conical fireball of the fuel element is close to the aerosol generating means, and the insulating material layer and/or the multiple passages provided in the fuel element cooperate to prevent the user from inhaling. Adequate heat transfer can also be achieved even during a relatively long dwell (smoldering) time between inhalations.

The aerosol generating means of the present invention is maintained at a relatively high temperature during the pause period between inhalations, and during the inhalation operation the additional heat, which is considerably increased by the preferred passageway provided in the fuel element, is primarily Used to evaporate aerosol generators. This increased heat transfer makes fuel energy more efficient, reduces fuel requirements, and allows for earlier delivery of the aerosol.

Furthermore, the composition of the fuel element, the number of passages in the fuel element,
It is possible to substantially control the combustion characteristics of the fuel element by appropriate selection of the size, shape and arrangement, insulating jacket, cigarette paper wrapper, and/or metal container (heat conducting means);
Thereby it is possible to control the heat transferred to the aerosol generating means and thereby vary the number of inhalations of the user and/or the amount of aerosol delivered into the user's mouth.

Generally, the length of fuel elements that can be used in the practice of the present invention is about 30 mm or less, preferably about 20 mm or less, and more preferably about 15 mm or less. Advantageously, the diameter of the fuel element is less than or equal to about 8 mm, preferably between about 3 and 7 mm, and more preferably between about 4 and 6 mm. The density of the fuel element that can be used in the present invention ranges from about 0.5 g/cc to about 1.5 g/cc, preferably 0.7 g/cc or more, more preferably 0.7 g/cc or more, as measured by mercury displacement, for example. is 0.8g/cc or more. In most cases, higher densities are desirable in order to make the fuel element's burn time comparable to that of a conventional cigarette and to provide sufficient thermal energy to generate the required amount of aerosol. .

The fuel element used in the present invention can be molded or extruded from crushed tobacco leaves, reconstituted tobacco material, or tobacco material substitutes (modified cellulose, degraded or prepyrolyzed tobacco material, etc.). It is advantageous to do so. Suitable materials include U.S. Pat.
No. 4347855, No. 3931824, No. 885574 and No.
No. 4008723 and “Tobacco Substitutes” by Shiteitsug, published by Noyce Data Corporation.
(1976). Use of other combustible materials as long as they can burn for a time comparable to that of a conventional cigarette and provide sufficient heat to generate the required amount of aerosol from the aerosol generating means. You can also do that.

Generally, it is preferred that the fuel element includes a carbon material such as that obtained by pyrolyzing or carbonizing a cellulosic material such as wood, rayon, tobacco leaf, coconut, paper, or the like. In most cases, combustible carbon is desirable because of its high heat production and low generation of incomplete combustion products. Preferably, the carbon content of the fuel element is about 20-40% by weight or more.

The most preferred fuel element that may be used in the practice of the present invention is US patent application Ser.
carbonaceous fuel elements (i.e., fuel elements consisting primarily of carbon) as described in
It is. Carbonaceous fuel elements are particularly advantageous in that they have low pyrolysis and incomplete combustion products, little or no visible sidestream smoke, low ash production, and high heat capacity. Of course, the aerosol delivered into the user's mouth should have no mutagenic effects, as determined, for example, by the Ames test (Mut.Res. of Ames et al.). 31:347–364 (1976
) and Nagas et al., Mutation Research 45:335 (1977)).

Combustion additives or modifiers may also be added to the fuel element to optimize its combustion and glowing properties. If desired, fillers such as diatomaceous earth and binders such as sodium carboxymethyl cellulose (SCMC) can also be added to the fuel element. Additionally, flavoring amounts such as tobacco extract can be added to the fuel element to impart a tobacco or other flavor to the aerosol.

Preferably, the fuel element is formed with one or more longitudinal passageways. These passageways serve to control heat transfer from the fuel element to the aerosol generating means. This heat transfer control is important both in terms of transferring enough heat to generate enough aerosol and in avoiding transferring so much heat that it degrades (decomposes) the aerosol generating agent. It is also important in in general,
These passageways impart porosity to the fuel element and increase the amount of initial heat transfer to the support by increasing the amount of hot gas reaching the support of the aerosol generating means. The passages also serve to increase the combustion rate of the fuel.

Generally, a large number of passageways, such as about 5 to 9, or more, as shown in FIG. 2A,
Especially when they are provided with relatively wide spacing between the passages, a high amount of conductive heat transfer is obtained, resulting in
High aerosol delivery rate can be obtained. Also, providing multiple passages facilitates ignition of the fuel element.

High conductive heat transfer tends to increase the amount of CO contained in the main stream of the aerosol. To reduce the level of CO, you can reduce the number of passages or
It is possible to increase the density of the fuel element, but in that case,
Generally, the fuel element becomes difficult to ignite, reducing conductive heat transfer and thus reducing aerosol delivery rate and volume. However, if the passages are closely spaced, the combustion will cause the passages to become more
Since the two passages are combined into one passage, the amount of combustion products contained in
It has been found that the amount of CO is low.

The optimal arrangement, shape and number of passages in the fuel element are
It is determined to provide a stable and sufficient amount of aerosol, facilitate ignition, and reduce CO emissions. Various combinations were tested regarding the placement, shape, and/or number of passages in the carbonaceous fuel elements used in each embodiment of the present invention. As a result, fuel elements having about 5 to 9 passages relatively closely spaced to combust and coalesce into one large passage are preferred fuel elements for use in the present invention, and are particularly preferred. It was found to best meet the requirements of carbonaceous fuel elements. This is believed to be true for a variety of non-carbon fuel elements that can be used in the practice of the present invention.

Variables that affect the rate at which passages in a fuel element burn and coalesce include the density and composition of the fuel element, the size, shape, and number of passages, the spacing between passages, and the pattern in which the passages are arranged. for example,
Density 0.85g/cc with 7 passages of approximately 0.5mm diameter
In the case of carbonaceous fuel elements, the passages must be within the diameter of the core, i.e., the diameter of the smallest circle circumscribing the outer edge of the passages, in order to coalesce into one passage when combusted, i.e. about 1.6 It should be placed within the range of mm to 2.5 mm. If the diameter of each of these seven passages is increased to about 0.6 mm, the diameter of the core that is coalesced by combustion will be about 2.1 mm to about 3.0 mm.
increases to

Another preferred fuel element passage arrangement that may be used in the practice of the present invention is shown in FIG. 2B. This passage arrangement has been found to be particularly advantageous in reducing CO emissions and facilitating ignition. In this preferred arrangement, a plurality of passageways 16, preferably about five to nine, are formed in a short section at the firing end of the fuel element, and the passageways merge into a large cavity 97, forming a large cavity 97 at the suction end of the fuel element. It has been extended to. The multiple passages on the lighting end provide a large surface area that is desirable for easy ignition and early delivery of the aerosol. The cavity 97 extending over approximately 30-95%, preferably over 50%, of the total length of the fuel element ensures uniform heat transfer to the aerosol generating means and directs the aerosol into the main stream.
It plays a role in reducing the amount of CO delivered.

The aerosol generating means used in the practice of the present invention is physically separate from the fuel element.
By "physically separate" is meant that the support, container, or chamber containing the aerosol generating agent does not mix with the combusting fuel element or portion thereof. As previously mentioned, this configuration serves to reduce or eliminate thermal degradation of the aerosol generator and the presence of sidestream smoke. Although the aerosol generating means is not a part of the fuel element, it is preferable that the aerosol generating means be in a conductive heat exchange relationship with the fuel element, and it is preferable that the aerosol generating means be brought into contact with or in close proximity to the fuel element. This conductive heat exchange relationship is preferably established by a heat conductive material such as a metal tube or metal foil, and the heat conductive member is preferably arranged so as to be spaced apart from and retracted from the ignition end of the fuel element. .

Preferably, the aerosol generating means comprises one or more thermally stable materials carrying one or more aerosol generating agents. A thermally stable material as used herein is one that can withstand high temperatures of, for example, 400° C. to 600° C., which occur in the vicinity of the fuel element, without decomposing or burning. Although not necessarily preferred, other means of aerosol generation, such as thermally ruptured microcapsules or solid aerosol generators, are also viable, as long as they are capable of releasing sufficient aerosol-generating vapor to resemble tobacco smoke. It is within the scope of the invention.

Thermally stable materials that can be used as supports or carriers for aerosol generators are well known to those skilled in the art. A suitable support should be porous and capable of retaining the aerosol generating agent when not in use and capable of releasing the aerosol generating vapor when heated by the fuel element. The support, especially if it is a particulate material, may be housed in a container preferably formed of a thermally conductive material such as metal.

Suitable thermostable materials include thermostable carbons such as porous carbon, graphite, activated or inert carbon. Other inorganic solids such as ceramics, glasses, alumina, vermiculite, and clays such as bentonite are also suitable. Preferred carbon materials as supports are porous carbons such as PC-25 and PG-60 manufactured by Union Carbide, and SGL carbon manufactured by Calgon. A preferred alumina for the support is SMR-14-1896, available from Davidson Chemical Division of W.R. Grace and Company. This alumina is sintered at a high temperature of approximately 1000°C or higher, for example.
It has been washed and dried.

Suitable granular supports can also be prepared in a single step from carbon, tobacco wood or a mixture of carbon and tobacco wood using a machine manufactured by Fuji Paudal Co., Ltd. of Japan and sold under the trade name "Marmerizer". It has been found that it can be formed into compressed particles. This machine is covered by German Patent No. 1294351, US Patent No.
No. 3277520 (reissued as Patent No. 27214) and Japanese Patent Publication No. 42-8684.

The aerosol generating means used in the present invention is spaced from the ignition end of the fuel element by about 40 mm, preferably by about 30 mm, and most preferably by about 20 mm. The length of the aerosol generating means is about 2 mm to about 60 mm, preferably about 5 mm to 40 mm, most preferably about 20 mm to 35 mm.
can be in the range of The diameter of the aerosol generating means is about 2 mm to about 8 mm, preferably about 3 mm to about 8 mm.
It can be between 6 mm. If a non-granular support is used, the support can be provided with one or more holes to increase the surface area of the support and to increase air flow and heat transfer.

The aerosol generating agent used in the present invention must be capable of generating an aerosol at the temperatures that occur within the aerosol generating means when heated by the combusting fuel element. The aerosol generator is preferably composed of carbon, hydrogen, and oxygen, but may contain other components.
The aerosol generator can also be in solid, semi-solid, or liquid form. The boiling point of the aerosol generator and/or mixture of aerosol generators may be up to about 500°C. Materials with such properties include polyhydric alcohols such as glycerin and propylene glycol, and aliphatic esters of mono-, di-, or polycarboxylic acids such as methyl stearate, dimethyl dodecadiate, and dimethyl dodecadiate.

Preferred aerosol generators are polyhydric alcohols or mixtures of polyhydric alcohols, particularly preferred are glycerin, propylene glycol, triethylene glycol or mixtures thereof.

The aerosol generating agent can be dispersed around or within the aerosol generating means at a concentration sufficient to penetrate or coat the support, carrier or container. For example, the aerosol generator can be applied undiluted or in the form of a diluted solution to the support by techniques such as dipping, spraying, vapor deposition, and the like. The solid aerosol-generating component can be mixed with a support and uniformly distributed within the aerosol-generating means.

The amount of aerosol generating agent charged varies depending on the type of carrier or the type of aerosol generating agent, but in the case of a liquid aerosol generating agent, the amount is generally about 20 mg to about 120 mg, preferably about 120 mg. may range from about 35 mg to about 85 mg, most preferably from about 45 mg to 65 mg. As much as possible of the aerosol generating agent carried on the aerosol generating means is
It should be sent to users as WTPM. Preferably about 2% by weight or more, more preferably about 15% by weight, most preferably about 20% by weight of the aerosol generating agent supported on the aerosol generating means.
is sent to the user as WTPM.

The aerosol generating means may also contain one or more flavoring agents such as menthol, artificial coffee, tobacco extract, nicotine, caffeine, liquor, and other agents that impart flavor to the aerosol; , and any other desired volatile solid or liquid substances may also be included. Alternatively, these optional agents are optionally provided in a separate support or chamber provided between the aerosol generating means and the mouth end, e.g. in a passageway leading from the aerosol generating means to the mouth end. It can also be inserted into the aforementioned tobacco inserts. If desired, these volatile agents can be
It can be used in place of some or all of the aerosol generators, in which case a non-aerosol flavor or the like is delivered to the user.

In a particularly preferred embodiment, the aerosol generating means comprises an alumina carrier;
a tobacco flavor modifier such as spray-dried tobacco extract, levulinic acid contained in the support; 1
It consists of seeds or more flavoring agents and an aerosol generator such as glycerin. This support may be mixed with compressed tobacco particles produced, for example, in a "marmerizer", and these tobacco particles may also be impregnated with an aerosol generating agent.

The smoking articles disclosed herein can be used as pharmaceutical delivery articles to deliver volatile, pharmacologically or physiologically active substances, such as efuedrin, metaproterenol, turbitutarin, etc., as an aerosol generator. or can be modified for use as a pharmaceutical delivery article.

As shown in the illustrated embodiments, the smoking article of the present invention includes a tobacco charge or plug, or a tobacco-containing material downstream of the fuel element, for imparting tobacco flavor to the aerosol. can be set. In that case, hot steam is drawn through the tobacco material, extracting and vaporizing the volatile substances within the tobacco material without burning or substantially pyrolyzing it.

One preferred location for locating the tobacco material charge is shown in FIGS. 1 and 2, in embodiments where a thermally conductive member or container is provided between the aerosol generator and the tobacco material jacket. around the outer periphery of the aerosol generating means to increase heat transfer to the tobacco material. In these embodiments, the tobacco material also serves as a shield for the aerosol generating agent and acts to mimic the feel and aroma of conventional cigarettes.

Another preferred location for disposing the tobacco material is within the aerosol generating means. In that case, the tobacco material may be mixed with a support for the aerosol generating agent or may be used in place of the support. The tobacco-containing material can include any available tobacco material, such as burley tobacco, hot air-cured tobacco, Turkish tobacco, reconstituted tobacco, extruded or compressed tobacco mixtures, tobacco-containing sheets, and the like. Advantageously, tobacco blends are used to provide a variety of flavours. The tobacco-containing material may also contain conventional tobacco additives such as fillers, casings, reinforcing materials such as glass fibers, humectants, and the like. Flavors and flavor modifiers may also be added to the tobacco material. Preferred thermally conductive members used in the practice of this invention should be located sufficiently recessed so as not to interfere with the firing end of the fuel element, but the It must be close to the ignition end so that conductive heat transfer can take place even during the initial and intermediate suction operations.

As shown in each of the embodiments illustrated herein, the thermally conductive member preferably contacts or overlaps the rearward portion of the fuel element and at least a portion of the aerosol generating means, and extends at least approximately from the ignition end of the fuel element. Retractable by 3 mm, preferably about 5 mm or more. Preferably, the thermally conductive member extends for at most about half of the total length of the fuel element, and more preferably for at most about 5 mm of the rear end portion of the fuel element, overlapping or in some way contacting it. let In this way, since the heat conduction member is retracted from the ignition end, it does not interfere with the ignition or combustion of the fuel element, and also functions as a heat sink to reduce the contact point between the fuel element and the heat conduction member. It works to digest the combustion when it burns up to the point where it burns. Further, the heat conductive member does not protrude forward from the fuel element even after the fuel is consumed.

Preferably, the thermally conductive member constitutes a thermally conductive container surrounding the aerosol generating agent. Alternatively, a separate conductive container may be provided, particularly in embodiments using particulate supports or semi-liquid aerosol generators. The conductive container not only functions as a container for the aerosol generating agent, but also facilitates heat distribution to the aerosol generating agent and a surrounding tobacco jacket, which is provided in a preferred embodiment, and also facilitates the distribution of the aerosol generating agent to the smoking article. It plays a role in preventing the spread or migration to other parts. The container also provides a means for controlling the pressure drop through the smoking article by varying the number, size, and/or location of passageways for delivering aerosol toward the mouth end. . Additionally, in the embodiment of FIG. 2 in which a tobacco material jacket is disposed around the outer periphery of the aerosol generating means, channels or channels are provided in the peripheral wall of the container to direct and control the flow of vapor through the tobacco material. A slot can be provided. The use of containers also has the effect of simplifying the manufacture of smoking articles by reducing the number of parts and/or manufacturing steps required.

The insulation material that can be used in the practice of the present invention is preferably formed from one or more layers of insulation material in the form of a resilient insulation jacket. The insulating jacket has a thickness of at least 0.5 mm, preferably at least about 1 mm, more preferably about 1.5 to
The thickness should be approximately 2 mm. The heat insulating jacket preferably extends over half or more of the total length of the fuel element, and more preferably covers the entire outer peripheral surface of the fuel element and all or part of the aerosol generating means. As shown in the embodiment of FIG. 1, different materials may be used to thermally isolate these two components of the smoking article (the fuel element and the aerosol generating means).

Insulating materials that can be used in the present invention generally include inorganic materials obtained from, for example, glass, alumina, silica, vitreous materials, mineral wool, carbon, silicon, boron, organic polymers, cellulosic materials, etc., and mixtures thereof. Or it is made of organic fibers. silica airgel, perlite formed into mats, strips or other shapes;
Non-fibrous materials such as glass can also be used. The insulation material is preferably elastic and has the effect of resembling the feel of a conventional cigarette, and is approximately sized so that it melts during use.
It is preferable that the material has a softening temperature of 650 to 700°C or less and does not burn during use. however,
Slow-burning carbon and similar materials can be used. These materials function primarily as an insulating jacket, retaining a significant portion of the heat created by the fuel element and directing it to the aerosol generating means. Since the insulating jacket becomes hot in close proximity to the burning fuel element, it conducts some heat toward the aerosol generating means.

Preferred insulation materials for the fuel element include:
There are ceramic fibers such as glass fibers. Mani Glass 1000 from Manning Paper Company, USA
Glass fibers sold under the trade name Maniglas 1200 are suitable. Preferably, the glass fiber material for the present invention has a low softening point of about 650° C. or less as measured by ASTM Test Method C338-73. Also preferred for use in the present invention are glass fibers sold by Owens Corning, USA under product numbers 6432 and 6437. This glass fiber has a softening point of about 640°C and melts during use when applied to the present invention.

Several types of inorganic fibers are commercially available that are held together by a binder (eg, PVA) that serves to maintain structural integrity. Binders that emit unpleasant odors when heated are e.g.
It should be removed before use by introducing air at about 650°C for up to about 15 minutes. If desired, about 3% by weight of pectin can be added to the fibers to provide mechanical strength to the insulating jacket without producing unpleasant odors.

Alternatively, some or all of the insulation may be replaced with loose or tightly compressed tobacco material. The use of tobacco material as a substitute for some or all of the insulation provides, in addition to its function as insulation, the additional function of adding tobacco flavor to the mainstream aerosol and generating a side stream of tobacco flavor. do. In the preferred embodiment of FIG. 2, the aerosol generating means is enclosed by a tobacco jacket.
The tobacco material jacket functions as a non-combustible insulator and also functions to impart a tobacco flavor to the mainstream aerosol. Furthermore, when the fuel element is wrapped in tobacco material, the tobacco material is combusted at most only up to the area where the fuel element is combusted, that is, at the point of contact between the fuel element and the aerosol generating means. It is preferable to do so.
Such a configuration may include compressing the tobacco material around the fuel element, as in the embodiment of FIG.
and/or can be achieved by using a conduction heat sink. Alternatively, such an arrangement may include treating the cigarette paper wrapper and/or the tobacco material itself with a substance such as sodium silicate which has the effect of extinguishing the tobacco material at the location where the tobacco material overlaps the aerosol generating means. obtained by doing.

If the insulation is comprised of a fibrous material other than tobacco, shielding means may be provided between the insulation and the mouth end of the smoking article. Such shielding means may be constituted, for example, by an annular member made of dense cellulose acetate tow. Such an annular body is abutted against a fibrous insulation material and sealed at both ends, for example with an adhesive, to prevent air flow through the tow.

In most embodiments of the invention, the fuel element-aerosol generating means assembly is attached to the mouthpiece, but the mouthpiece may be provided separately, for example in the form of a cigarette holder. The mouthpiece provides a passageway for the vaporized aerosol generating agent to the user's mouth. The mouthpiece has a suitable length (preferably about 35-50 mm or more) to keep the hot cone away from the user's mouth and fingers, so that the hot aerosol can reach the user. Give enough time to cool before reaching the mouth.

The mouthpiece is preferably inert to the aerosol generating agent and may have a water-resistant inner layer to minimize loss of aerosol due to condensation or filtration and to protect against other components of the smoking article. It should be able to withstand high temperatures at the interface with the A preferred mouthpiece is the cellulose acetate cylinder used in the examples illustrated herein. This barrel functions as a resilient outer member and has the effect of mimicking the feel of the mouth end of a conventional cigarette. Other suitable mouthpieces will be readily apparent to those skilled in the art.

A filter tip can be used as the mouthpiece of the article of the invention to mimic the appearance of a conventional filtered cigarette. Such filters include low efficiency cellulose acetate filters and hollow or slotted filters made of plastic such as polypropylene. These filters have little interference with aerosol delivery.

A smoking article according to a preferred embodiment of the invention comprises:
When smoked under FTC smoking conditions, the first three puffs can deliver at least 0.6 mg of aerosol as total wet particulate matter (WTPM). (FTC smoking conditions are 2 seconds of inhalation (35 ml total volume) with 58 seconds of smoldering (pause) periods.) Smoking articles according to more preferred embodiments of the present invention are A three-dose inhalation action can deliver 1.5 mg or more of aerosol. In the most preferred embodiment,
FTC smoking conditions can deliver 3 mg or more of aerosol in the first three puffs.
Preferred embodiments also deliver an average of at least about 0.8 mg (WTPM) of aerosol per dose over at least about 6, and preferably 10, doses.

[Brief explanation of drawings]

FIG. 1 is a longitudinal cross-sectional view of a smoking article according to one embodiment of the present invention. FIG. 1A is an end view of the fuel element used in the embodiment of FIG. FIG. 1B is an enlarged end view of the metal container used in the embodiment of FIG. FIG. 2 is a longitudinal cross-sectional view of a smoking article according to another embodiment of the present invention. FIG. 2A is an end view of the fuel element used in the embodiment of FIG. 2. 2nd B
The figure is a longitudinal cross-sectional view of a preferred fuel element passage arrangement. 10: fuel element, 12: aerosol generating means,
38: Aerosol generator support (carrier), 7
2: Heat insulating layer (insulating jacket), 89: Paper wrapper, 90: Metal capsule or container, 94: Heat insulating layer (insulating jacket), 96: Metal capsule or container.

Claims (1)

Claims: 1. At least one at least one substance physically separate from the fuel element and disposed between the fuel element and the mouth end of the smoking article to receive heat from the burning fuel element.
an aerosol generating means including various types of aerosol generating agents; a heat insulating layer surrounding at least a portion of the fuel element; and a paper wrapper configured to remain at least partially unbroken to restrict air flow to the burning fuel element during smoking.