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I34:ici pd- ' a ) I97g B'RUA]BAUGH' , GRAVES, DONOHUE F, RAYTIOND! 30 ROCKEFELLER'PLAZA NEW YORK, N.Y. 100'20' TO' ALL WHOM IT MAY CONCERN: have in-rented an improvement in NICOTINE' TRANSFER' PRaCESS of which the following is a Be it known that SPECIFIiCATION . I The present i!nventionlrelates to a novel and highly efficient nicotine transfer process, and, more particuiarl!y, o a process for transferring nicotine from altobacco source o a nicotine deficient tobacco, a tobacco filler materiaL,, S reconstituted.tobacco (referredito as "reconstituted'lieaf" or "RL"').or to a non-tobaccoisubstance. The flavor of tobacco, RL or the like to:wflich naturally occurring nicotine is transferred by the process, is:usuaLly improved and the receiving material is thus more d'esirable for use in altobacco: 10 product. The nicotine source tobacco (from whichinitotine is transferred)', may, because of a loweredinicotine cont'ent„ also be improved'and more useful. The transfer process of the' present invention is also useful outside the tobacco industry iinithat the nicotine-receivi.ng, mateTial can be used as a Is nicotine source for various purposes unrelated to tobacco C products. -I-

Various techniques are known for prod'ucing nicotine . free tobacco or a tobacco having a reduced nicotine content.. Denicotinizing processes frequently employed'are based'either on the principle of dii'.rect.solvent extraction of nicotine 5 compounds whereby soluble compounds are washed out, or on the principle of leaching the tobacco with an alkaline aqueouss solution which d'epends upon a chemical reaction to break down insoluble compounds whi'ch thereafter are washed out. Most, if not all of these prior art techniques, however, suffer 10 from the fact that they significantly rob the treatCed tobacco~ of properties generally identified'with a quality smoking product. The process of the present invention offers a significant advance in tobacco technology'by, for one thing,, providing a simple, economical and effective process for 1s' reducing the nicotine content of tobacco without the usual accompanying, degredation of the physical properties of the tobacco or smoke, such as the flavor,, fragrance or burning, qualities. Moreover,, the process is useful for transferring naturally occurring,nicotine from tobacco having a generally 20' high nicotine conten~t to a nicotine deficient tobacco, tobacco filler materialis, or RL (reconstituted leaf) which are used inn the production of cigarettes and other smoking,products_ It should'be noted however that a low nicotine tobacco having properties which make it generally unusable canialso be used 25 as the nicotine donor in the present process. In accordance with the invention, the:material to which nicotine is tolbe transferred (receiviing substrate) is contacted'with a strong acid -2- or an ammonium salt of a strong acid.

~ J-b-.l~~ The substrate is driedl,, andi t}iereafter layered, mixed or other- wise contacted (depending upon the pirysicali characteristics of the donor material an&substrates), with the tobacco fromiwhich nicotine is to be transferred (hereinafter the "donor tobacco"). 5 The combined'donor tobacco and reaeivi'ng substrate are then, subjected to:mild heating,which rapidly effects a transfer of a significant percentage of'the nicotine present in the donor tobacco to the substrate. Alternatively, the donor tobacco and . receiving substrate may be stored at roomitemperature, in which 10 case the nicotine transfer effected'occurs more slowly. Upon completion of the heat treatment or after a suitable storage period at room temperature, the donor tobacco, and the substrate,,are cooled,, if necessary, andithe donor tobacco may be physically separated from.the substrate onito 15 which the naturally occurring nicotine given up by the donorr tobacco has been, fixed' as a saIt, ii.e.,, a nicotine salt. While the present process is not to be circumscribed by any particular reaction mechanism, it is proposed that possible.mechanisms underlying the process involve the rel'ease' 20 of at least a portion ofi'the nicotine in the dbnor tobacco either or both as a result of the exposure to heat and the decomposing,salt deposited on the substrate and the subsequent reaction of the nicotine released from,the donor tobacco withh the strong acid'to formia stable nicotine salt on the receiving 25 substrate carrying the:strong aci'd. Over long periods of time, as in storage, reliease of the niicotine apparently occurs in the same fashion and to the same extent, as occurs with heating, but more slowly due tolthe lower temperatures. C .C~ N .-~. ~ ~ -3-

It has been~found!that as much as about fifty percent (5'0s)' of the nicotine content of the donor tobacco can be transferred in accordance with the present process when the donor tobacco is combined with the receiving substrate and' 51 heated for as little as sixty (60) minutes at 90°C. As is apparent from the data in the Tables hereinbelow, the rate of heating,,both as to time:and temperature, affect the rate of the nicotine transfer and the amount of nicotine whichlis transferredL Nevertheless, the presence or absence of heat in 110 the reaction phase of the process appears not to be critical to the overall success of the process. The substrate to which the nicotine is transferred is selected with *a view to the desired objective of the transfer process with the physical and chemical~ characteristi~cs of'the 1!5 process in mind. If the objective is to enrich the nicotine content of a!tobacco substance (e.g., a low nicotine tobacco or RL'), the selectilon to bee made i~s clear from the objective. If the objective is to improve the donor tobacco, the receiving, substrate selected'should have physical and chemical properties 20 compatible with the process.,, namely, non-reactivity with the acid'or salit,,the abilities to accept and retain the acid or salt, the ability to:withstand heating (if transfer is to be accelerated by heating)',,, the ability to be contacted effectively by'mixing or layering with the source tobacco, the ability to be 25 separated from the tobacco, and the ability to be further pro- cessed, if requi~red, for an end use. Generally, a liquid- permeable sheet material,, such as cloth, canvas or paper, iss useful as a receiving substrate because -4-

2343u able to hold the acid' or salt,and can be easily'hanzlLed and'_ separated'from the donor tobacco. In the tobacco:industry, the pxocess~is especially attractive as applied in enriching the nicotine content of' 5 reconstituted tobacco leaf (I"Rh"). RL is made from tobacco scrap by-products which normally contain only 20% to 25$' of the nicotine found in the average tobacco Iamina and thus is an, essentially non-nicotine filler source for cigarettes. By transferring nicotine from a donor tobacco source to the RL 10 sheet, the RL is significantly improved as a filler, t'huss contributing to the quality of the cigarette. The primary criterion for the selection of a suitably strong acid for use as a impregnant for the substrate is that the acid shoul&have a pKa of about 3.5 or less. Furthermore, 1'S non-volatile aci'ds are generally preferred over the more volatile acids. Accordingly, preferred strong,acids include phosphoric, tartaric,, citri1c, sulfuric', malic, lactic, nitri~c and hydrochloric acids. When used alone as the impregnant the concentration of the acidisolution should be in the range of about 1% to about 20 10%, with the preferred range being,from about 5% to 10t. The amount of'the acid impregnant deposited on the substrate may range from about ig, to 25% and! preferably 10 0' to 25%. Where the impregnant is~ a saIlt of a strong acid and strong,base, the selection of the acid component is dictated 25 by the foregoing parameters. The sole criterion for th,e seliection of a suitable strong base depends on the presence of an ammonium cation; hence any ammonium salt of a strong acid ivill! be suitable as an impregnant for the substrate. Preferred ammonium salts are mono and diammonium phosphate, diammonium sulfate, diammonium 0QQ9181(; _5,_

11 I citrate and'ammonium chloride. The concentrationlof the salt impregnant, like that of the acid generally ranges from!about U to:about 10%; however concentrations ranging,from about 5% to about 10% are preferred., The amount of the salt depositedion 5 the substrate can also range from about 1% ' to~ about 2'5%I and preferably 110% % to 2:5g'. Accordingly, it has been found that a 5% acid or salt solution will deposit an amount of about 12% of the acid or salt impregnamt byy weight on the substrate, and 10 a 10% acidlor salt solution will't deposit aniamount of about 22% by weight of said acid or salt impregnant on the substrate. It should be noted, however that the actual amount of acid or salt deposi~tedlon the substrat'e depends somewhat on the porosity of the substrate material selected for use.. 15. Any conventional method which adequaltely effects thee impregnation of'the substrate with a suitable strong acid or an ammonium salt of a strong acidimay be used, dipping or spraying being exemplary., Moreover, the manner in which the donor tobacco and treated substrate are contacted is not crit'icaL as long as 20 the two materials are interleaved'or intermixed in reasonably intimate mutual contact. When a combinedmass of donor tobacco~ and'. treated receiving substrate i!s stored at toom temperature, it has been found that after about five weeks a maximum nicotine transfer 2'5 has been effected'. Where the combined mass is heated, the applicable temperature is characterized as mild and'ranges from anywhere from slightly above room temperature up to about 105°C, but preferably from about 6'0°C to about 95°C'. Temperatures in excess of 105°C may and'.generally do result in some reduction 30' in quality of the tobacco. The 1!ength of heating time is obviously - 6'- a00419'1,7

dependent on the temperature usedi. However, as noted earlier, I significant nicotine transfer has beenieffected'ih one hour at 9'5°'C. At the upper range of temperatures which may be used,, the h~eating phase should not exceed the amount of time required' to 5 effect the desired transfer to avoid possible degradation of the tobacco. Any conventional technique based on size or density may be utilized to separate the donor tobacco from the substrate material. It should be reeognized', huwever, that the selection 10 of a1suitable separation technique often depends onithe type of the tobacco employed as the donor tobacco and' especial'1'y the need to preserve the physi~cal properties of both the tobacco and substrate. From the foregoiing, discussion it can be seen that the IS process according to the i~nvention, enables the manipul'ation of' the nicotine content of tobacco materials, such as cut leaf and reconstituted leaf, by removal of nicotine from a suitable nicotine tobacco source or by the addition of nicotine to a low nicotine tobacco material!. As mentioned above, however, the process may 20 also be used to:transfer nicotine from any donor tobacco source (be it high or low in nicotine content) for a myraid of other uses. The economies of the nicotine transfer method dis- cl!osed herein.should be apparent both from the simplicity and 25 efficiency of the process as further illustrated by the examples described beloia.. O O EhAF1PLE' 11 0 ' 0;h iPA A donor tobacco control was selected having a 6.0°s 40 nicotine content (by weight). A'standard grade of absorbant ~'

cellullose.sheet (laboratory filter paper) having a 0.0% nicotine content was chosen as the substrate control. The paper sub- strate was treated with 3% solution of diammonium phosphate and dried at room temperature. Thereafter it was determined 5 that the amount of diammonium phosphate deposited!was 7.0% by weight. Equal weights of cut donor tobacco (control) and the salt impregnated paper substrate were uniformly layeredlin two stacks, one of which was heated four one hour at 95°C and the other for two hours at 95°C. After the heating stage, the stacks 10 were allowed1to cool to about room temperature, and the dbnor tobacco was mechanically separated from the substratie. Analysis of the nicotine content of the paper substrate gave the following data. TABLE 1 L5 Samplie Description ~ N'i~cotine 1'. Treated paper substrate exposed to.donor tobacco for 1 hour at 95°C 2'.1'Og 2. Treated paper substrate. 20 exposed to donor tobacco for 2 hours at 95°C 2.65% EXAMPLE 2 The procedure of Example L was repeated except that the paper substrate was replaced by a reconstituted tobacco leaf, 25 (RL) substrate,,having a 0.6$nicotine content'by weight and the. RL was treated'..with 4% soluti'on:of diammoni~um phosphate. After drying, it was found that the RL containe&9.0% by wei'ght of deposited salt. Analysis of the nicotine content of the RL upon completion of,the process gave the following data. O' . -i~ 40

TABLE 2 Sample Description $' Ni~cotine 1. Treated'RL exposed to donor tobacco for I hour at 9'S'aC. 2.441$ 2. Treated'RL exposed to donor tobacco for 2 hours at 95°C 3.05% The data from the above Tables 1 and 2 demonstrate 10 that the nicotine content was reduced iinitobaccos deemedlun- desi~rabliy high in nicotine and transferred to bothi a porous paper and reconsti~tuted leaf. Nloreover, it can be inferred from the above data that the donor tobacco exposed to the diammonium phosphate treated RL (',receivino,substrate) under the 15 conditions of Example:2 was reduced in nicotine by approximately 501,. Moreover, the exposedi RL, previously deficient in nicotine, was significantly increasedlin nicotine content, i.e. from 0.6f to 2.,44W and 3.05%'. The following experiments were conducted to confirm 20 that substantially all of the nicotine lost by the donor tobacco migrates to the treated!receiving substrate. EXAIvIpLE 3 Reconstituted'leaf (RL), having a nicotine content of 0.6% (by weight) was contacted with a,4.8a soluti~on of diammonium 25 phosphate. After drying,it was determined that about 121 of the salt was deposited on the RL substrate:. Two batches of mixed donor tobacco andlimpregnated substrate were prepared by layering the RL substrate betweenitwice its weight of the O -9-

'' 23436 donor tobacco,_tlie nicotine content of which was 6.00' by weight. One mixture was heated for one hour at 95°C'and the other mixture was heated for two hours at 95°'C. Thereafter both mixtures were cooled and separated. 5 EXAMPLE 4 Example 3 was repeatediusing a standard grade of laboratory filter paper as the receivi~ng substrate and whereiin, the treated paper was layered with the same weight of'donor tobacco. 110 ~ EXAMPLE 5~ Example 3 was repeated using a 4.8% solution of'mono- ammonium phosphate. E Xb1AP LE 6 . Example 4 was repeated using a, 4.8% solution of 115 monoammonium phosphate. Nicotine analyses of the RL,paper and donor tobacco, used in: accordance with procedures in Examples 3-6 are presented in Table 3. TABLE 3' 20 Sample Description $ Nicotine 1. Treated! RL not exposedi to tobacco (controll), 0.6$' 2'. Treated paper not exposed O' to tobacco (controli), 0.0% 25 3. Donor tobacco (control) 6.0% rG~ Ir~ ~ N -10-