Ulllted States Patent
`
`[19]
`
`[11] Patent Number:
`
`4,922,901
`
`Brooks et a1,
`[45] Date of Patent:
`May 8, 1990
`
`
`4,601,287
`
`4,771,796
`
`7/1986 Royche et all.
`...................
`131/273
`:1. ...N
`
`9/1988 Myer ................................. .. 131/273
`
`FOREIGN PATENT DOCUMENTS
`0186280
`7/1986 European Pat. Off.
`..... .. 128/200.14
`2653133
`5/1978 F d. R .
`fG rmany .
`2704218
`3/1978 F:,d_ R211: Sf Gfirmany _
`3300992
`7/1984 Fed. Rep. of
`Germany ...................... .. 128/200.14
`212825610/1972 France.
`48-8231
`3/I973 Japan .
`’
`.
`W086/02528
`5/1986 PCT Int1Appl.
`197946
`4/1924 United Kingdom _________ __ 123/204,17
`
`OTHER PUBLICATIONS
`Novoloid Fibers, Kirk—Othmer: Encyclopedia of Chemi-
`cal Technology, vol.
`16, Third Edition,
`1981, pp.
`125_138_
`Adsorption of Gases in Multimolecular Layers, Journal
`of the American Chemical Society, Braunauer et al., vol.
`PP- §09':S3_’19v Fe‘; 1938-d P
`_t G
`t
`1
`,
`e a .,
`gg
`35_‘j,’;P’]‘;’g7 "’f"“"
`'9” “”
`°"””’
`Novoloid Fibers, American Kynol, Inc,, Catalogue.
`.
`_
`{1;rtr_rz;zr3’t1’:‘h3ct1t7ztr.1er—-%i_gal:5i Blljrrmher
`ssts an
`xammer-— im er y
`.
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`
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`
`re
`
`I
`ABSTRACT
`[571
`Drug delivery articles employ an electrical resistance
`heating element and an electrical power source to pro-
`vide a dose of a drug in aerosol form. The articles ad-
`vanta eously comprise a disposable portion and a reus-
`bl
`E
`11
`Th d.
`b1
`0 {on norm“ in_
`8 6 COMO 6-r~
`6
`1.513053 6 P F1
`_»
`Y.
`cludes a drug and an air permeable resistance heating
`element having a surface area greater than
`m /g,
`which usually carries an aerosol forming material. The
`reusable controller normally includes a puff-actuated
`current actuation means, a time-based current regulat-
`ing means to control the temperature of the heating
`1
`t and a batter
`ower Su
`1
`3 amen’
`Y P
`PP Y‘
`.
`_
`136 Claims, 7 Drawing Sheets
`
`[75]
`
`[54] DRUG DELIVERY ARTICLES UT1L1z[N(}
`ELECTRICAL ENERGY
`Inventors:
`Johnny L. Brooks; Donald L.
`Roberts, both of Winston-Salem;
`Jerry S. Simmons, Rural Hall, all of
`N.C.
`,
`[73] Assigneez R.'J. Reynolds Tobacco Company,
`Wmston-Salem, N-C
`
`_
`[21] APP1‘N°" 241’641
`[22] Filed:
`Sep. 8, 1988
`
`[51]
`
`[56]
`
`Int. CL5 .................. .. A61M 16/00; A6lM 15/06;
`A24K 47/00
`[52] U.S. C1. .......................... 128/203.26; 128/202.27;
`128/203-27? 128/204-133 128/20417;
`128/203-129 131/273? 131/329
`[58] Field of Search .................... .. 128/202.21, 203.12,
`128/203-13’ 203115’ 20317’ 20326’ 20327’
`204-13» 20014’ 20023’ 20024’ 204'17’ 20227
`References Cited
`U.S. PATENT DOCUMENTS
`1,771,366
`7/1930 Wyss et al.
`................... .. 128/203.27
`2,030,075
`2/1936 Robinson ........ ..
`123/203.23
`2,057,353 10/1936 Whittemore, Jr.
`......
`1
`2,104,266
`1/1938 McCormick . . . . .
`.. .. ..
`2,284,591
`5/1942 Rose ........... ..
`128/200.14
`2,332,799 10/1943 Hunn etal.
`..
`i28/2oo.14
`2,974,669
`3/1961 Ellis . . . . .. . . . .
`. . . . . . .. 131/ 172
`39200319
`3/1955 Gilbert --
`123/208
`33891690 6/1975 Guamien "
`131/185
`3’918’464 11/1975 Kolodziej """"“
`131/173
`4,036,224 7/1977 Choporis et al.
`128/205.29
`4,090,513
`5/1978 Togawa .......... ..
`128/207.14
`4,133,313
`1/1979 (3,055 et a1_ ,_
`......,, 131/173
`4,141,369
`2/1979 Burruss ....... ..
`131/171 A
`4,164,230 8/ 1979 Pearlman .-
`131/ 171 R
`4-193,411 3/ 1930 Fafis 9131-
`131/171R
`482141146
`7/1930 Schimwski "
`128/20327
`4'246’913
`1/1981 Ogden et 31'
`131/171 A
`......
`4,303,083 12/1981 Burruss, Jr.
`.. ...... 131/271
`4,523,589
`6/1985 Krauser ...... ..
`128/203.27
`4,564,748
`1/1986 Gupton
`219/497
`4,580,583
`4/1986 Green, Jr.
`......................... .. 131/330
`
`
`
`44
`
`48
`
`42 38
`
`I6
`
`/10
`46 49 54 40 52 as
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`18
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`
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`
`34
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`NU MARK Ex.1036 p.1
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`NU MARK EX.1036
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`

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`U.S. Patent May 8,1990
`
`Sheet 3 of 7
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`4,922,901
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`NU MARK Ex.1036 p.4
`NU MARK Ex.1036
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`

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`US. Patent May 8, 1990
`
`Sheet 4 of 7
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`4,922,901
`
`NU MARK Ex.1036 p.5
`NU MARK Ex.1036
`
`

`
`U.S. Patent May 3,1990
`
`sheet 5 of 7
`
`4,922,901
`
`NU MARK Ex.1036 p.6
`NU MARK Ex.1036
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`

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`

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`U.S. Patent May 3, 1990
`
`Sheet 7 of 7
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`4,922,901 L
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`2
`
`I49
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`FIG.IO
`
`NU MARK Ex.1036 p.8
`NU MARK Ex.1036
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`

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`1
`
`4,922,901
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`DRUG DELIVERY ARTICLES UTILIZING
`ELECTRICAL ENERGY
`
`BACKGROUND OF THE INVENTION
`
`The present invention relates to drug delivery articles
`which employ an electrical resistance heating element
`and an electrical power source to deliver a drug in
`aerosol form. As used herein, the term “drug” includes
`articles and substances intended for use in the diagnosis,
`cure, mitigation, treatment or prevention of disease; and
`other substances and articles referred to in 21 USC
`321<g)(1).
`Over the years, there have been proposed numerous
`smoking products, flavor generators and medicinal in-
`halers which utilize electrical energy to vaporize or
`heat a volatile material for delivery to the mouth of the
`user.
`
`U.S. Pat. No. 2,057,353 to Whittemore, Jr. proposed
`a vaporizing unit. In particular, a wick reportedly car-
`ried liquid medicament by capillary action to a point
`where the liquid was vaporized by an electrical resis-
`tance heating element.
`U.S. Pat. No. 2,104,266 to McCormick proposed an
`article having a pipe bowl or cigarette holder which
`included a resistance coil (i) wound on an insulating and
`heat resisting material, and (ii) contained in an insulated
`chamber. Prior to use of the article, the pipe bowl was
`filled with tobacco or the holder was fit with a ciga-
`rette. Current then was passed through the resistance
`coil. Heat produced by the resistance coil was transmit-
`ted to the tobacco in the bowl or holder, resulting in the
`volatilization of various ingredients from the tobacco.
`A thermostatic switch was employed to maintain a
`predetermined temperature range to which the tobacco
`was heated.
`U.S. Pat. No. 3,200,819 to Gilbert proposed a smoke-
`less, non-tobacco cigarette having a flavor cartridge,
`such as a porous substrate impregnated with mentho-
`lated water. The article included a battery for powering
`a tube or bulb which was illuminated before assembly.
`The bulb was placed in a tubular liner, which was in
`turn located within a tube of plastic having the size,
`color and form of a cigarette. In use, the illuminated
`bulb reportedly heated the flavored air drawn through
`passages formed between the bulb and the tubular liner.
`As such, warm, moist, flavored air was delivered to the
`user.
`
`French Patent Publication No. 2,128,256 to Ribot et
`al. proposed an article for delivering denicotinized
`smoke. The proposed article included a sealed ampule
`which contained pressurized denicotinized smoke. An
`electric resistor was immersed in the smoke. In use, the
`terminals of the resistor were pushed into contact with
`a microbattery causing the resistor to generate heat and
`heat the smoke within the ampule. Draw by the user
`reportedly caused warm smoke to exit a valve near the
`mouthend of the article.
`g
`Japanese Patent Publication No. 8231/73 to Takeda
`proposed a cigar-shaped inhaler which included a bat-
`tery powered Nichrome wire to heat air that, in turn,
`evaporated an essence from an essence container. The
`Nichrome wire was energized by either a manually-
`actuated or a draw actuated “on-off" switch.
`West German Patent Application No. 2,653,133 to
`Kovacs proposed a smoking simulator having an inter-
`nal battery which could accelerate or control the vapor-
`ization or emission of aromatic substances for delivery
`
`5
`
`10
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`15
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`20
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`25
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`30
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`35
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`45
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`50
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`55
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`60
`
`65
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`2
`to the user. In supplemental West German Patent Ap-
`plication No. 2,704,218, Kovacs described the use of a
`vacuum or draw-actuated switch to switch "on“ the
`battery operated heating coil.
`A draw actuated, pressure transducer switch was
`described in U.S. Pat. No. 4,246,913 to Ogden et al., as
`part of a smoke aversion therapy article which deliv-
`ered a small electrical shock to a smoker whenever the
`smoker drew on a cigarette.
`U.S. Pat. No. 4,141,369 to Burruss proposed an article
`similar to the previously discussed McCormick articles.
`Burruss proposed a container which was electrically
`heated to a temperature sufficient to volatilize desired
`components from smoking material
`inserted therein.
`Heated air passing through the container during draw
`reportedly carried volatilized materials to the mouth of
`the user.
`U.S. Pat. No. 4,303,083 to Burruss proposed a pipe
`having an electrical resistance heating element, a manu-
`ally operated “on-off’ power switch, and an opening
`above the resistance element for the addition of volatile
`compound. During use,
`the volatile compound was
`applied, using a squeeze tube or eye dropper, to a heated
`surface within the pipe, apparently on a puff-by-puff
`basis. The volatile compounds reportedly were vapor-
`ized, mixed with air drawn into the pipe, and inhaled by
`the user.
`PCT Publication No. W0 86/02528 to Nilsson et al.
`proposed an article similar to that described by McCor-
`mick. Nilsson et al proposed an article for releasing
`volatiles from a tobacco material which had been
`treated with an aqueous solution of sodium carbonate.
`The article resembled a cigarette holder and reportedly
`included a battery operated heating coil to heat an un-
`tipped cigarette inserted therein. A switch was acti-
`vated to supply current to the heating coil. A tempera-
`ture sensor reportedly disconnected and reconnected
`the battery in order to maintain the temperature gener-
`ated by the device in a narrow temperature range. Air
`drawn through the device reportedly was subjected to
`elevated temperatures below the combustion tempera-
`ture of tobacco and reportedly liberated tobacco flavors
`from the treated tobacco contained therein.
`U.S. Pat. No. 4,735,217 to Gerth et al. proposed a
`“cigarette-shaped” medicament dosing article having a
`pellet of vaporizable medicament and a Nichrome resis-
`tance heating element connected in series with a battery
`power source and a draw actuated switch. In their only
`working example, the Nichrome heating element alleg-
`edly achieved a temperature in the range of 190+ F. to
`220+ F. (90° C. to 105° C.) within a two second puff,
`which apparently was sufficient to volatilize menthol
`from a menthol pellet. At Column 8, lines 43-63, Gerth
`et al. went on to speculate that their article could be
`used to vaporize nicotine from a nicotine-containing
`pellet and that they believed it feasible to coat the heat-
`ing element with a nicotine-containing compound in
`lieu of using a vaporizable pellet.
`However, it is believed that it would not be possible
`to coat a Nichrome heating element, of the type de-
`scribed by Gerth et-al., with enough vaporizable liquid
`material to deliver sufficient volatile material
`to the
`user, over a 6 to 10 puff life. It also is believed that the
`article of Gerth et al. would not be able to provide
`enough electrical energy to (i) vaporize volatile mate-
`rial until near the end of a typical two second puff, or
`(ii) provide a high enough temperature (eg., 150" C. to
`
`NU MARK Ex.1036 p.9
`NU MARK Ex.1036
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`

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`3
`, 350° C.) to vaporize many volatile materials within a
`two second puff,
`including many desirable aerosol
`forming substances and many volatile flavor compo-
`nents. In addition, even with only a single AA battery,
`the article described by Gerth et al. is more than 3 times
`the diameter and many times heavier than a typical
`cigarette and is provided with a relatively imprecise
`draw actuated control switch and with no means of
`regulating the current or heat during the puff.
`Despite many years of interest and effort, none of the
`foregoing articles employing electrical energy has ever
`realized any significant commercial success, and it
`is
`believed that none has ever been widely marketed.
`Moreover,
`it
`is believed that none of the foregoing
`electrical energy articles is capable of providing an
`acceptable delivery of a drug to the user, especially
`over a 6 to 10 puff, or greater, product life.
`Thus, it would be desirable to provide an article for
`delivering a drug in aerosol form, which utilizes electri-
`cal energy and which is capable of delivering accept-
`able quantities of a drug and aerosol over at least 6 to 10
`puffs.
`
`SUMMARY OF THE INVENTION
`
`The present invention relates to drug delivery articles
`which employ an electrical resistance heating element
`and an electrical power source to provide a drug in
`aerosol form. Preferred articles can produce aerosol
`almost immediately upon commencement of a puff, as
`well as provide the controlled production of aerosol
`throughout the puff and over a 6 to 10 puff product life.
`In one aspect of the invention,
`the drug delivery
`article includes a disposable portion (eg., a cartridge)
`which utilizes an air permeable high surface area electri-
`cal resistance heating element
`that normally carries
`aerosol forming substance and/or a drug prior to use.
`This resistance heating element typically is a porous
`material having a surface area greater than 1 m2/g, as
`determined using the Brunaver, Emmett and Teller
`(BET) method described in J. Am. Chem Soc., Vol. 60,
`p. 309 (1938); and Adsorption Surface Area and Porosity,
`Gregg et al., Academic Press, NY (1967). Preferably,
`the heating element is a fibrous carbon material, most
`preferably having a surface area greater than about
`1,000 m2/g. (In contrast, the surface area of the Ni-
`chrome metal resistance element of Gerth et al. is be-
`
`lieved to be about 0.01 m2/g.) Preferably, such porous
`heating elements are impregnated with liquid aerosol
`forming substances, such as glycerin. Such heating ele-
`ments are particularly advantageous in that they are
`capable of holding and efficiently releasing relatively
`large quantities of liquid aerosol forming substances and
`drug constituents. For example, such heating elements
`can carry enough aerosol forming substances to provide
`aerosol for 6 to 10 puffs, or more.
`Drugs useful herein are those which can be adminis-
`tered in an aerosol form directly into the respiratory
`system of the user. Typical of such drugs are those
`which are used in the treatment of asthma, emphysema,
`bronchitis, epilepsy, shock, hypertension, cardiac ar-
`rhythmia, sinus congestion, allergies, convulsions, anxi-
`ety, schizophrenia, and the like. Examples of suitable
`drugs include ephedrine, metaproterenol,
`terbutaline,
`dopamine, phenytoin, diazepam, propranolol, diphen-
`hydramine, and the like.
`Another important aspect of the invention relates to
`the various configurations of the disposable portions
`described herein. For example,
`in certain preferred
`
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`4,922,901
`
`4
`embodiments, the disposable portion advantageously is
`provided with an electrical connection means at one
`end thereof. This electrical connection means includes
`means for connecting the resistance element to a battery
`or other external power source, and preferably includes
`an air passageway used in conjunction with the pre-
`ferred puff actuated current actuation means. In other
`preferred embodiments,
`the disposable portion is
`adapted for connection to the external power source via
`connectors located on the reusable controller. In certain
`preferred embodiments, the resistance heating element
`is located centrally in the disposable portion and/or
`does not occupy a significant portion of the cross-sec-
`tional area of the disposable portion. In other preferred
`embodiments, the resistance heating element is located
`adjacent an end of the disposable portion, and/or at
`least substantially fills the cross-sectional area of the
`disposable portion or the air passageway therethrough.
`A reusable controller can be used with the disposable
`portions of the invention. This reusable controller nor-
`mally includes a current actuation means, a separate
`current regulating means to control the temperature of
`the heating element, and a battery power supply. Alter-
`natively, the electrical power supply can be provided
`separately from the current actuation and current regu-
`lating means; eg., as a separate battery pack or as normal
`household current stepped down by an appropriate
`transformer. The reusable controller can be in the form
`
`of a pipe, a reusable mouthpiece, a hand-held unit or
`other portable form into which the disposable portion
`can be inserted. The use of such a reusable article with
`the disposable portions of the invention is particularly
`advantageous in that it permits the use of (i) relatively
`large power sources, capable of generating 10 to 40
`watts of power or more, and (ii) accurate and sophisti-
`cated current actuation and current regulating means
`that normally would be too costly to incorporate into a
`single use, disposable article.
`Preferably, the current actuation means is puff actu-
`ated, so that current flows through the resistance heat-
`ing element to produce aerosol only during draw by the
`user.
`
`To use the articles of the invention, the user simply
`inserts the disposable portion containing the drug into
`the controller, to electrically connect the heating ele-
`ment to a circuit including the current actuation and
`current regulating means and to the battery. When the
`user draws on the mouthend of the article, the preferred
`current actuation and current regulating means permit
`unrestricted or uninterrupted flow current through the
`resistance heating element
`to generate heat rapidly.
`This heating volatilizes the aerosol forming substances
`and/or drug, which in turn form an aerosol and pass
`through the article and into the mouth of the user. At
`the same time, the current regulating means (i) regulates
`current flow through the heating element to control
`heating of the resistance element and the temperature"
`experienced thereby, and (ii) prevents overheating and
`degradation of the aerosol former. When the user stops
`drawing on the article,
`the current actuation means
`prevents further current flow through the heating ele-
`ment and disables the current regulating means. This
`process continues, puff after puff, until the user decides
`to stop drawing on the article (i.e., the dose of the drug
`is complete). At that point, the disposable portion can
`bale removed and discarded, and a new one inserted in its
`p ace.
`
`NU MARK Ex.1036 p.10
`NU MARK Ex.1036 p.
`
`

`
`5
`In another aspect of the invention, the current actua-
`tion means, the current regulating means, and/or the
`electrical power source may be incorporated into the
`portion of the article containing the electrical resistance
`heating element, so that the reusable controller may be
`reduced in size or even eliminated.
`Preferred articles of the invention are capable of
`delivering an average of at least 0.5 mg, more preferably
`at least 0.8 mg, of aerosol and/or drug per puff, mea-
`sured as wet total particulate matter (WTPM), under
`conditions of 2 second, 35 ml puffs, taken once every 60
`seconds. Preferred articles of the invention can deliver
`such material, preferably in visible form, for a plurality
`of puffs, preferably at least about 6 puffs, more prefera-
`bly at least about 10 puffs, under such conditions.
`As used herein, and only for the purposes of this
`application, “aerosol” is defined to include vapors,
`gases, particles, and the like, both visible and invisible,
`generated by action of heat from the resistance heating
`element upon aerosol forming substances and/or a drug
`located on the resistance element or elsewhere in the
`article.
`
`10
`
`15
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`20
`
`The articles of the present invention are described in
`greater detail in the accompanying drawings and in the
`detailed description of the invention which follows.
`
`25
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`FIG. 1 is a longitudinal, partial sectional view of an
`article of this invention;
`FIG. 1A is a sectional view of a portion of the em-
`bodiment shown in FIG. 1 taken along lines 1-1;
`FIG. 2 is a longitudinal, partial sectional view of an
`article of this invention;
`FIG. 3 is a perspective of an article of this invention
`including an exposed inner view of the reusable portion
`thereof;
`FIGS. 4, 5, and 6 are longitudinal, partial sectional
`views of preferred articles of this invention showing the
`disposable portions and cut-away views of the control-
`Iers;
`FIGS. 7 and 8 are longitudinal sectional views of
`additional articles of the invention; and
`FIGS. 9 and 10 are representative schematic dia-
`grams of time-based control circuits and related wiring
`for preferred controllers useful in this invention.
`DETAILED DESCRIPTION OF THE
`PREFERRED EMBODIMENTS
`
`Referring to FIG. 1, drug delivery article 10 includes
`a disposable cartridge 12 and a reusable, hand-held
`controller 14. The disposable cartridge 12 includes elec-
`trical connection plug 16, resistance heating element 18
`carrying an aerosol forming substance, mouth end filter
`22, and a resilient overwrap 24. The preferred control-
`ler 14 includes a case 26, a puff actuated current actua-
`tion mechanism 28 having the form of a pressure sensi-
`tive switch, a time-based current control circuit 30, and
`a chamber 32 into which battery power supply 34
`(shown as batteries 34A and 34B) is inserted.
`The resistance heating element 18 employed in car-
`tridge 12 preferably is a fibrous material having a high
`surface area and an adsorbant, porous, wettable charac-
`ter, in order to carry a suitable amount of aerosol form-
`ing substance for effective aerosol formation. Suitable
`heating elements preferably have surface areas above
`about 50 m3/g, more preferably above about 250 m2/g,
`and most preferably above about 1,000 m2/g.
`
`30
`
`35
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`4,922,901
`
`6
`Preferred heating elements normally have low mass,
`low density, and moderate resistivity, and are thermally
`stable at the temperatures experienced during use. Such
`heating elements heat and cool rapidly, and thus pro-
`vide for the efficient use of energy. Rapid heating of the
`element also provides almost immediate volatilization
`of the aerosol forming substance. Rapid cooling pre-
`vents substantial volatilization (and hence waste) of the
`aerosol forming substance during periods when aerosol
`formation is not desired. Such heating elements also
`permit relatively precise control of the temperature
`range experienced by the aerosol forming substance,
`especially when the preferred time based current con-
`trol means described herein is employed.
`Preferred resistance heating elements include carbon
`filament yarns available from American Kynol,
`lnc.,
`New York, N.Y., as Catalog Nos. CFY-0204-l, CFY-
`0204-2, and CFY-0204-3. Such yarns reportedly have
`surface areas of about 1,500 m3/g and resistivities of
`about 10 to about 30 milliohm-cm. See, Kirk-Othmer:
`Encycl. Chem. Tech., Vol. 16, 3rd Ed., pp.
`l35"l36
`(1981). Representative lengths of such yarns range from
`about 15 to about 50 mm. Other preferred heating ele-
`ments include carbon felts and activated carbon felts
`available from American Kynol, Inc., as Catalog Nos.
`CN-157(HC), CN-210(HC), ACN-211-10, ACN-210-10,
`and ACN-157-10. Such felts typically have surface
`areas of about 1,500 m2/g and resistivities of about 5 to
`about 30‘ milliohm-cm. Such felts can be used in the
`form of circular discs having diameters of about 4 to 8
`mm, as described in greater detail hereinafter with ref-
`erence to FIGS. 4-6. Other suitable heating elements
`include porous metal wires or films; carbon yarns,
`cloths, fibers, discs or strips; graphite cylinders, fabrics
`or paints; microporous high temperature polymers hav-
`ing moderate resistivities; porous substrates in intimate
`contact with resistance heating components; and the
`like.
`
`the heating element 18 is impregnated
`Preferably,
`with or otherwise carries one or more aerosol forming
`substance in order that the aerosol forming substances
`are in a heat exchange relationship with the electrical
`heating element. The aerosol forming substances used in
`this invention are capable of forming aerosol during
`periods when the heating element generates heat. Such
`substances preferably are composed of carbon, hydro-
`gen and oxygen, although other material such as water
`can be employed. The aerosol forming substances can
`have a solid, semi-solid, or liquid form. Examples of
`suitable aerosol forming substances include water; poly-
`hydric alcohols such as glycerin, propylene glycol and
`triethylene glycol; aliphatic esters of mono-,di—, or poly-
`carboxylic acids such as methyl stearate, dimethyl
`dodecandioate, dimethyl tetradecandioate; a drug; and
`the like, as well as mixtures thereof.
`While the loading of the aerosol forming substance
`can vary from substance to substance and from heating
`element to heating element, the amount of liquid aerosol
`forming substance used typically will be greater than
`about 15 mg and preferably ranges from about 25 mg to
`about 50 mg.
`The drug can be used as an aerosol forming sub-
`stance, and can be carried by the resistance heating
`element. The drug also can be placed between the resis-
`tance heating element and the mouth end of the car-
`tridge, such as in mouthend filter 22 or in a separate
`chamber or cartridge located between the resistance
`heating element and the filter. In such instances, the
`
`NU MARK Ex.1036 p.11
`NU MARK Ex.1036 p.
`
`

`
`4,922,901
`
`7
`drug can either form an aerosol or be eluted by the
`aerosol forming material. As with the aerosol forming
`substance, the loading of each drug can vary depending
`upon the particular drug and the particular dose re-
`quired.
`Although drugs can be employed to form an aerosol
`with or without the aforementioned aerosol forming
`substances, it is desirable to employ such aerosol form-
`ing substances with drugs in order that an identifiable,
`visible aerosol is provided. As such, the user readily can
`identify when a dose of the drug is complete.
`A heat resistant, electrically insulative strip, tube or
`spacer 36, preferably is provided in order to maintain
`the heating element in place and to prevent the heating
`element from contacting itself. The insulative spacer 36
`can be a cellulosic sheet treated with fire retardant, an
`aluminum foil having a surface coating of aluminum
`oxide, an insulative ceramic material, a heat resistant
`plastic material such as a polyimide, or the like.
`- The electrical connection plug 16 preferably is manu-
`factured from a resilient, electrically insulative material
`such as a thermoplastic material. The plug 16 includes
`two electrical connector pins or prongs 38, 39 con-
`nected to the_ends of heating element 18 via connectors
`40, 41. The pins 38, 39 engage with electrical terminals
`42, 43 located in electrical connection receptacle 44 of
`the controller 14. Plug 16 also includes a passageway 46
`through which tube 48 from pressure sensing switch 28
`extends. As shown in FIG. 1A, pins 38; 39 and passage-
`way 46 are offset with respect to the longitudinal axis of
`plug 16.
`A portion of the length of the electrical connection
`plug 16 preferably is circumscribed by a collar 49 hav-
`ing the form of a thermoplastic tube, which preferably
`is friction fit around a portion of the length of the plug.
`The collar 49 in turn is secured to the remaining portion
`of the cartridge via overwrap 24 using tipping paper 52
`or other appropriate means such as adhesive, a friction
`fit, or the like. Preferably, the collar 49 includes one or
`more peripheral air inlet openings 54 which provide a
`flow of ambient air through the cartridge during draw.
`Alternatively, the air inlet can be positioned through
`the extreme inlet end of the cartridge or elsewhere
`through the periphery of the cartridge, such that drawn
`ambient air passing through the cartridge to the mouth
`of the user passes the resistance element.’
`The mouthend filter 22 is provided for aesthetic pur-
`poses. It preferably is a low efficiency filter made from
`a melt blown thermoplastic such as polypropylene. For
`example, the filter can be manufactured by pleating a
`web of nonwoven polypropylene available from Kimb-
`erly-Clark Corp. as experimental melt blown, macrofi-
`ber polypropylene PP-100-F. Alternatively, the mouth-
`end filter 22 can be manufactured from cellulose acetate
`tow, or the like. Preferably, the filter material is over-
`wrapped with a paper plug wrap 58.
`To maximize aerosol and dose of the drug which
`otherwise would be diluted by radial (i.e., outside) air
`infiltration through the overwrap 24, one or more lay-
`ers of non-porous paper can be used to envelop the
`cigarette. Examples of suitable non-porous papers are
`cigarette papers commercially available from Kimber-
`ly-Clark Corp. as KC-63-5, P878-5, P878-l6-2 and
`780-63-5. If desired,
`the overwrap can be a resilient
`paperboard material, foil-lined paperboard, or the like;
`and the paperboard can be circumscribed by a cigarette
`paper wrap.
`—
`
`10
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`15
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`20
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`25
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`30
`
`35
`
`40
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`45
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`50
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`55
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`60
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`65
`
`8
`The reusable controller 14 includes a case 26 or outer
`housing which provides a convenient and aesthetic
`holder for the user. The outer housing 26 can have a
`variety of shapes and can be manufactured from plastic,
`metal, or the like. Controller 14 includes an insulative
`receptacle 44 which includes plug-in connectors 42, 43
`for engagement with prongs 38, 39 of plug 16. Recepta-
`cle 44 also includes tube 48 which is inserted into pas-
`sageway 46 of plug 16 to be in airflow communication
`with the internal region of the cartridge. The other end
`of tube 48 is in airflow communication with pressure
`sensing switch 28, so that changes in air pressure which
`occur within the cartridge during draw can be sensed
`by the switch.
`Controller 14 also preferably includes a control cir-
`cuit 30, which is connected to a puff actuated, differen-
`tial pressure sensitive switch 28 by electrically conduc-
`tive wires (not shown), as well as to batteries 34A and
`34B via battery terminal 62. The control circuit 30 pref-
`erably is time based. That is, the preferred current con-
`trol circuit preferably is based on controlling the time
`period during draw during which current passes
`through the resistance element. This time based control,
`in turn, controls the temperature experienced by the
`resistance element and by the aerosol forming sub-
`stances. Preferred pressure sensitive switches and con-
`trol circuits, and their connection power source 34 and
`resistance element 18, are described in greater detail
`hereinafter with reference to FIGS. 9 and 10.
`While the heat needed to volatilize the aerosol form-
`ing substance (and the drug in appropriate cases) during
`a puff varies for each particular substance and drug,
`sufficient heat usually is necessary, during a puff, to heat
`the aerosol forming substance to a temperature above
`about 120“ C.
`in order to volatilize an appropriate
`amount of the aerosol forming substance. More typi-
`cally, a temperature aboveabout 150° C., often above
`about 200° C., and sometimes as high as about 300° C. to
`about 350° C.,
`is necessary to volatilize adequate
`amounts of the aerosol forming substance during a puff.
`However, it is desirable to avoid heating the aerosol
`forming substance to temperatures .substantially in ex-
`cess of about 550° C.
`in order to avoid degradation
`and/or excessive, premature volatilization of the aero-
`sol forming substance.
`For a particular resistance heating element and a
`particular aerosol forming substance, a sufficient cur-
`rent is required, during each puff, to generate the heat
`necessary to volatilize enough aerosol forming sub-
`stance to provide an adequate amount of delivered aero-
`sol. For the preferred aerosol forming substances and
`the preferred carbon heating elements described herein,
`an 18 volt battery usually generates sufficient power
`(i.e., about 18 watts) to heat the aerosol forming sub-
`stance to a suitable temperature to volatilize the aerosol
`forming material almost immediately after current actu-
`ation, i.e., within about 0.5 second, preferably within
`about 0.1 second. The 18 volt battery can be provided
`using two fully charged 9 volt manganese dioxide-zinc
`transistor batteries (as shown in FIG. 1) or three 6 volt
`lead acid batteries. Also useful is a silve