Patent Application
20130306085
The present invention relates generally to altering the taste characteristics of an aerosol, and more particularly, to a method and articles for controlling an inner filter temperature of an aerosol-generating product or device to alter the aerosol taste characteristics.
Conventional mentholated and non-mentholated less than full flavor cigarettes include perforated or porous filter paper wrapper to provide air dilution of the mainstream smoke. During puffing of a cigarette, fresh air penetrates the perforated filter wrapper paper and dilutes the cigarette mainstream smoke. Accordingly, total delivered cigarette mainstream smoke is reduced by the air dilution. In this manner, the overall particulate and gas phase components of the mainstream smoke are reduced.
Even though the use of air dilution to reduce total mainstream smoke delivery is very effective and controllable, it might result in unfavorable influences on taste signature because it dilutes the tobacco taste and it is known to produce an undesirable harshness to the smoker. Cigarette designers typically undertake extensive development efforts at significant costs to develop specific tobacco blends in an effort to overcome these undesirable influences on the cigarette taste characteristics.
Other technologies used in the industry to reduce specific gas phase constituents include incorporating carbon particles, polymeric resins and clays in the filter structure. These additives remove non-desirable components such as aldehydes, ketones, aromatic hydrocarbons, and other volatile organic compounds from the mainstream smoke. They have been found to be very effective abatement technologies. However, smokers report these cigarettes tend to exhibit off-taste. These taste changes potentially affect the rate of adoption of these potentially reduced exposure smoking articles.
The off-taste changes in taste signature resulting from the abatement technologies occur because the abatement technologies are not singularly specific to any smoke chemical component and remove desirable chemical components from the smoke stream.
On the whole, cigarette mainstream smoke is characterized as formed by particulates, semi-volatiles, and volatile components. The distributions of these components determine the smoking experience. Abatement technologies implemented upstream the cigarette mouth piece and toward the heating zone (i.e., air dilution, adsorption beads, column aeration modification, incorporation of modified tobacco leaf and stem) change the smoke component distribution and the rate of smoke fraction delivered as well. These changes, because the might alter the gas-particulate distribution/amount, affect the organoleptic characteristics of the delivered smoke.
Furthermore, the perceived taste or strength of the cigarettes classified as having lower levels of “tar” and nicotine are progressively lower than that of cigarettes which are classified as “full flavor” cigarettes. It has been proposed to add numerous flavorants to the cut filter of lower “tar” cigarettes to enhance the taste, strength and satisfaction of such cigarettes. However, such addition of flavorants generally results in cigarettes that might be perceived as harsh or irritating to the mouth, nose and throat of the smoker.
Because of these shortcomings, the art is continually searching for means to improve the flavor of smoke produced by a burning tobacco rod. Therefore it is desirable to provide less than full flavor cigarettes such as “low tar” or/and “ultra-low tar” cigarettes capable of delivering a good tobacco taste, strength and smoking satisfaction characteristic of a full flavor low tar cigarette while being perceived as palatable but not as overly harsh, irritating or having off-taste.
The present invention is directed to methods, compositions, and cigarette designs to control the gas-particulate partition of smoke components in the delivered smoke of smoking articles to enhance their organoleptic properties with respect to full flavor (FF) cigarettes and reduced tar or less than full flavor (LF) cigarettes.
According to an aspect of the invention, a method of manufacturing a smoking article having enhanced taste characteristics is provided. The method comprises: selecting a heat adsorbing or reflecting material to apply to a filter of the smoking article, the heat adsorbing or reflecting material having one or more properties associated therewith; and applying the heat adsorbing or reflecting material to the filter, the at least one heat adsorbing or reflecting materials being configured to control the inner temperature of the filter.
The heat adsorbing or reflecting material may comprise a metallized foil material.
The metallized foil material may comprise one of aluminum, silver, copper or gold.
The applying the heat adsorbing or reflecting material may comprise inserting the heat adsorbing or reflecting material into the body of the filter.
The applying the heat adsorbing or reflecting material may comprise wrapping a filter absorbing matrix of the filter with the heat adsorbing or reflecting material.
The smoking article may comprise a less than full flavor smoking article, and the method may further comprise applying one or more ventilation holes to the filter.
The one or more properties may comprise at least one of a type of heat adsorbing or reflecting material, a surface roughness, or a mass.
The selecting the heat adsorbing or reflecting material to apply may be based on at least one of the one or more properties.
The smoking article may comprise a full flavor smoking article, and wherein the applied heat adsorbing or reflecting material is configured to raise the inner temperature of the filter.
The smoking article may comprise a less than full flavor smoking article, and the applied heat adsorbing or reflecting material may be configured to lower the inner temperature of the filter.
The method may further comprise determining at least one of a position, size, number and shape of one or more ventilation holes to be applied to the filter to control a temperature gradient of the filter.
The method may further comprise determining at least one of a size and a material composition of the heat adsorbing or reflecting material to control a temperature gradient of the filter.
According to another aspect of the disclosure, a smoking article is provided. The smoking article comprises: a filter material that captures and substantially removes unwanted components in an aerosol; and a foil that is configured to control temperature of the aerosol, so as to provide a full-bodied flavor to the aerosol.
A longitudinal length of the foil in the smoking article may comprise at least 50% of a longitudinal length of the filter material.
The smoking article may further comprise a hole provided in the foil to control a temperature of the aerosol.
The foil may comprise an annular axial foil material. The foil may comprise: aluminum; silver; copper; or gold. The foil may be configured to decrease temperature of the aerosol.
According to a still further aspect of the invention, a smoking article is provided that comprises: a filter material that captures and substantially removes unwanted components in an aerosol; and a foil that is configured to control temperature of the aerosol, so as to provide a full-bodied flavor to the aerosol, wherein: a longitudinal length of the foil comprises at least 50% of a longitudinal length of the filter material; the foil comprises a hole to control temperature of the filter material; the foil comprises an annular axial foil made of at least one of aluminum, silver, copper, and gold.
The invention will be better understood after a reading of the following description of the preferred embodiments when considered with the drawings in which:
Referring now to the drawings in general, it will be understood that the illustrations are for the purpose of describing preferred embodiments of the invention and are not intended to limit the invention thereto.
Methods and articles are described herein for enhancing the taste characteristics of the smoke produced by a smoking article during a smoking experience by controlling the temperature of an inner filter associated with the smoking article. A heat adsorption or reflective material, such as a metallized foil material, may be applied to the filter to exercise the temperature control. The metallized foil may be, for example, a metallized foil insert, a metallized foil wrapper, a metallized foil core, etc. The methods described herein may apply to less than full flavor smoking articles, enhancing the taste characteristics to more closely replicate the taste characteristics of a full flavor smoking article. In some aspects, the taste characteristics of a full flavor smoking article may also be further enhanced.
It is understood that the smoking article mainstream smoke is formed by combustion products and vaporized effluents, and they are normally classified as particulates, semi-volatiles, and volatiles. During smoking, they reach the filter and they might condense in the filter depending on their condensation temperature/rate, therefore the smoke stream shows different gas-particle compositional distribution.
According to the equilibrium gas/particle theory for aerosol developed by Pankow, Chen, and Hennigan, the gas to particle partitioning coefficient, Kp, for aerosol may be determined as follows:
In Equation (1), Cp is the compound's particle-phase concentration, Mo is the mass concentration of the absorbing organic phase (including water), and Cg is the compound's gas-phase concentration. Kp can also be predicted from the properties of the partitioning species, where R is the ideal gas constant, T is temperature, fom is the organic fraction of total particulate mass, MWom is the average molecular weight of the absorbing organic (and aqueous) phase, t is the particle-phase activity coefficient, and p is the saturation vapor pressure.
As reported in R. J. Reynolds Internal Document No. 50220 (Bates 502208295-502208361) dated May 1985, the statistical relationship for N=40 smokers between ventilation technology and harshness, taste, and other subjective attributes is well documented. Provided below in Table I is a summary of these statistical relationships which show that mainstream smoke air dilution produced by air ventilation is negatively correlated with a number of subjective customer measurements. These negative correlations are caused by changes in filter inner temperature which affect component condensation rates and gas-particle partition. Accordingly, technologies that affect filter temperature also affect the smoke gas-particle phase balance with a consequent reduction in customer satisfaction with regard to organoleptic smoke attributes.
Based on the mainstream smoke gas-particle balance described in equation (1) that relates gas-particle partition to temperature, it was discovered that by modulating and/or controlling Kp, it is possible to improve the organoleptic properties of smoking articles and increase low tar products acceptability by adult consumers. In particular, this is useful when the smoking articles include abatement technologies, such as dilution and adsorbing filters that, change the gas to particle balance of acceptable smoking articles.
Furthermore, it was discovered that the application of equation (1) to cigarette filter configurations indicates that Kp depends on the filter temperature, the smoke vapor pressure of its chemical components, the average mass of the particle phase, and the overall mole fraction activity coefficients of the particle phase taste-given compounds. In accordance with some aspects of the invention, strategies to control Kp to enhance and/or control smoking articles organoleptic properties include, for example, controlling temperature, controlling saturation vapor pressure, and/or controlling the average molecular weight of adsorbing phases. As described in more detail herein, in accordance with some aspects of the invention, the inner temperature of a filter of a smoking article can be controlled by wrapping the filter with metallized foils or other heat adsorbing or heat reflecting material.
Turning now to
The metallized foil or film may behave as a thermal insulator and/or heat exchanger. As described above, the foil properties may be controlled by varying the type, the surface roughness or/and the mass of the foil. For example, aluminum foil alloys may have a thermal conductivity in the range of about 120-180 W/(m.K) compared with about 429 W/(m.K) for silver foil. Likewise, aluminum foil alloys may have a heat capacity of about 0.90 J/(g.K) compared with about 0.23 (J/g.K) for silver. Accordingly, silver material when used as part of a filter wrapper of a smoking article can remove heat faster from the smoke stream than an aluminum wrapper. Different metal foils can be used alone or in combination to create zones with different thermal properties.
As seen at 104, the selected heat adsorbing or reflecting material may be applied to the filter, wherein the heat adsorbing or reflecting material may be configured to control the inner temperature of the filter. In accordance with some aspects, the heat adsorbing or reflecting material may be provided in the body of the smoking article filter or applied as single/multiple filter wrapper layers, and/or co/off-axial wrappers in intimate contact with the filter material matrix. The heat adsorbing or reflecting material may be configured to cover 50% or more (e.g., along the axial length of the filter) of the plug wrap. It is noted that the heat adsorbing or reflecting material may be configured to cover less than 50% of the plug wrap. The smoking article may be a full flavor smoking article or a less than full flavor smoking article. Where the smoking article is a full flavor smoking article, the applied heat adsorbing or reflecting material may be configured to raise the inner temperature of the filter.
In accordance with some aspects, the smoking article may be a less than full flavor smoking article, wherein the applied heat adsorbing or reflecting material is configured to lower the inner temperature of the filter. When applied to a less than full flavor smoking article, the method 100 may additionally include applying one or more ventilation holes to the filter, as seen at 106. Applying the one or more ventilation holes may include determining a position, size, number, and/or shape of the one or more ventilation holes to apply to the filter in order to control a temperature gradient of the filter.
Various examples of the present invention comprising metallized foiled filter structures with and without ventilation holes are illustrated and described below. It will be understood that even though the illustrations show the metallized foils only in a portion of the filter, the foil could be extended to cover, if desired, both the mouth piece and the tobacco column. These illustrations do not show the final filter wrapper “tipping paper” that hold the cigarette filter to the tobacco column. These are non-limiting examples that could be used independently or combined with each other as required to meet desired filtering cigarette performance. For example, the filter may optionally include fragrance encapsulates, a tobacco matrix, adsorbent resins and other filter functionality modifiers in the filter material with the metallized foil function.
In accordance with some aspects of the invention, the densities, materials, and formulations of the inner and outer adsorbing layers 304, 310 may be different or substantially the same, as required to meet desired taste and filtering performance. For example, the inner core (or layer) 304 may include carbon embedded artificial/natural fibers and the outer layer 310 may include virgin cellulose acetate fibers. In another example, both the inner and outer layers 304, 310 may include cellulose acetate having different densities.
As seen in
The opposite behavior was exhibited in less than full flavor cigarettes having a metallized foil. As seen in
In the FF case the metallized foil acts as a heat shield so it contains the heat within the metallized foil measured zone. However, in the LF case two zones of different thermal characteristics are created. One of them is a warm zone which is located downstream of the ventilation holes which is warmed by the smoke stream, and the second, is a cool zone located upstream of the ventilation holes formed by the cooling of the air entering through the ventilation holes. Because the second zone is cooler than the first zone, heat moves from the hotter to the cooler zone therein, and acts as a heat sink and reduces the temperature of the warm smoke. So in the LF case, it was discovered that ventilated cigarettes that use metallized foil show an inner temperature gradient. Therefore, it has been determined that by controlling the position, size, number and shapes of the ventilation holes and the size and material composition of the metallized foil, it is possible to control the filter temperature gradient.
Table II shows tar, nicotine, and carbon monoxide (TNCO) delivery in accordance with several examples illustrating principles of the invention.
The methods described herein may be applied to less than full non-mentholated flavor cigarettes built with metallized foils. It has been found that less than full non-mentholated flavor cigarettes built with metallized foils are preferred more than twice non-foiled non-mentholated control cigarettes at essentially equivalent tar delivery. Specifically, a panel of twenty-eight non-menthol smokers evaluated two packs of each prototype and completed a questioner about their preference and perceived characteristics of the cigarettes. Preference was observed for metallized prototype which demonstrated statistical superiority in overall satisfaction and liking of overall taste, strength of taste, strength of tobacco taste, and smoothness. Strong directional superiority was observed in liking of aftertaste and draw. The metallized prototype cigarette was statistically superior to the control in similarity to the usual brand smoked by the panel with both products perceived as better than the usual brand. The test product was so different from the control and liked significantly more by the panelists that when they smoked the control, it was rated much lower across most of the liking scores in comparison to previous tests.
The methods described herein may also be applied to less than full mentholated flavor cigarettes built with metallized foils. It has been found that these cigarettes are preferred more than three times the non-foiled control mentholated cigarettes. The panel in this experiment consisted of thirty menthol 80 mm cigarette smokers who evaluated 2 packs of each prototype and completed a similar questioner as the one described above. Statistical analysis of the questioners shows a significant preference difference between this invented prototype and the control. This difference is reflected in the overall satisfaction scores. The prototype showed significantly greater liking in “strength of taste” with strong directional superiority in liking of “overall taste”; it was found smoother and “closer to just about right” in “strength of taste”, “strength of tobacco taste”, and “draw.”
The examples above were for cigarettes that have equal tar delivery and with the present invention show improved taste. Surprisingly, it was also discovered that the present invention can be used to achieve taste parity for cigarettes that have half the tar delivered than the control cigarette without the invention. Specifically, a panel of thirty traditional 100 mm cigarette smokers evaluated two packs of each prototype and completed a similar questioner as the one described above. The embodiment of the present invention in this study was characterized as having 5.4 mg of tar and 0.55 mg of Nicotine per cigarette. The control cigarette was characterized as having 10.7 mg of tar and 1.03 mg of Nicotine. Statistical analysis of the “liking” scores showed parity for the cigarettes.
Furthermore, with respect to improving the taste of a cigarette equipped with the invention described herein, an additional benefit is derived from the ability to reduce the overall tar delivery from a smoking article equipped with the invention described herein and achieve taste parity to a higher tar delivered from a cigarette not equipped with the invention described herein. The invention described herein has particular relevance in the ability to maintain the taste characteristics of a full flavor cigarette in a less than full flavor cigarette. As shown in
Tables III and IV illustrate the ability to achieve taste parity or better between a mentholated cigarette comprising aspects of the invention described herein and a mentholated full flavor cigarette not equipped with aspects of the invention described herein. To evaluate the taste characteristics of the cigarettes, a panel of 29 menthol 100 mm cigarette smokers evaluated two packs of each prototype and completed a questionnaire about the sensory differences between a 15.4 mg/cigarette control and a 10.7 mg/cigarette comprising principles of the present invention. An analysis of variance (ANOVA) was carried out on the returned questionnaire using a sequential monadic randomized block—2 packs per product—home use. As Tables III and IV illustrate, smokers had a positive response to the cigarette implementing aspects of the present invention.
Table V illustrates the ability to achieve taste parity or better between a mentholated silver class cigarette comprising aspects of the invention described herein and a mentholated gold class cigarette not equipped with aspects of the invention described herein. To evaluate the taste characteristics of the cigarettes, a panel of 60 consumers evaluated two packs of each sample and completed a questionnaire about the sensory differences between a 14 mg/cigarette control and an 8 mg/cigarette comprising principles of the present invention. ANOVA analysis was carried out on the returned questionnaire using a sequential monadic randomized block—2 packs per product—home use. As shown in Table V, smokers' opinions of the cigarette implementation aspects of the present invention were high.
In addition, table VI illustrates the ability to achieve taste parity or better between a nonmentholated Gold class cigarette comprising aspects of the invention described herein and a non-mentholated Gold class cigarette not equipped with aspects of the invention described herein. To evaluate the taste characteristics, a panel of 28 Gold class non-menthol smokers evaluated two packs of each sample and completed a questionnaire about the sensory differences between the cigarette comprising aspects of the present invention and a control at the same tar level. ANOVA analysis was carried out on the returned questionnaire using a sequential monadic randomized block—2 packs per product—home use.
According to the present invention, Kp was determined according to equation (1) based on Cp and Cg values measured using the method shown in
Referring to
Alternatively or in addition to enhancing taste characteristics of a smoking article by controlling the temperature, other methods may be used. For example, in some aspects, the saturation vapor pressure of the smoke produced during a smoking experience may be controlled by adding to the tobacco column/filter material ingredients that reduce or increase the vapor pressure such as glycols, fragrances, salts, amorphous/crystalline balance of solid fragrances, hydrophilic polymers, hydrogels, etc. In some aspects, the average molecular weight of absorbing phases may be controlled by increasing or reducing the filter density and/or the filter material composition.
While the invention has been described in terms of exemplary embodiments, those skilled in the art will recognize that the invention can be practiced with modifications in the spirit and scope of the appended claims. These examples given above are merely illustrative and are not meant to be an exhaustive list of all possible designs, embodiments, applications or modifications of the invention.
This application claims priority under 35 U.S.C. §119(e) to U.S. Provisional Patent Application No. 61/648,269, filed May 17, 2012, titled “METHOD AND APPARATUS TO CONTROL THE GAS-PARTICLE PARTITION OF AN AEROSOL TO ENHANCE ITS TASTE CHARACTERISTICS,” the disclosure of which is hereby expressly incorporated herein by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 61648269 | May 2012 | US |
