Tobacco Documents Online

~:,;y ~~ ~ ~ ~ Several'-- . I.."' .'r_ - . ••;~. tifie ex~er~im~ _:. entra inment~ °-fra~m~, f or the 'maJ9nnI~ suffic~ient tiecogy -i of- n n-v`v l8`flav~i best new. ~nO~tel,~a Date: November 26, 19,95 nventional cigarette has been mainly limited and those volatile compounds formed' by e. There are many non-vollatile flavoricom- our s.moking products, but no mechanism is fective concentrations of these materials to are scattered reports of very small trace nds like sugar, cellulose, rutin, piF(nents, reporting the appearance of traces of inor- e explained this phenomenon as due to the 11 pieces of ashi. Ash particles`larger than acco rod. Therefore, the inorganics in smoke to the organic/water particulate phase. by Dr. Osdene to design a speci'fic scien- unequivocally differentiate mechanical zation-cond'ensation phenomenoniresponsible rmationi. At that time I coul'd not findi finitive experiment which has never The deliiberate mechanical entrainment linstream smoke still offers one of the to designing truly new cigarette products. a L_ .Wovntj 1 -*2 1985 meeting of the American Association For Ae~~~ informationiwas gathered giving rise to this - - f ._. ~.... , propoaa 1jormu 4at~d ,two pronged research attack that may bring delib- erat8 ~p~han3cal~'ent into real'ity. This attack is divided into two simultan~ous`-researGh' ., pt*~Ums, both of which are necessary and are both now rrithin;;;scientific~f As i1A; " ::~ rtF v'~~:; • ~ ~~~ ~~^4<,+: 1 Or the deve ~o)b4~e#iti'Sf this program of deliberate mechanical entrain- ~ mient,'`."I have arbitrau°i1'ivided the research efforts into two main areas: a.) Neutron Acti1vation.'An,a sis and Radiographic Research and b. ) ~-tulti- A r, P MOiR I S U. S. A. I CE CORRESPONDENCE I CMIMION D, Y I Ri(i I N I A Component Erlcapsulatiori.:. The appropriate research scenarios are as follows: "i M IkI% My previous theories.about how cigarette ashiiis mechanically entrainedi can be summarized in the ~llowing: As the organic miaitter in tob3cco is consumed during combustion, ai frail inorganiic skeleton is left which has ~ little mechanical strength'and small pieces are broken off by the adr drawn CA throughi the rod during the puff. Also as the organic matt(-r is consumed in the approaching thermal gradient, isol3tedismall pieces of tobacco, semi- a.) Neutron ActivatjkqI)~Analysis and Radiographic Research 04

cambusted matter, clusters of structural materials, and perhaps clusters of large molecul!es are ejecte:r' from the leaf'into~the moving air stream (puff) where so-ne of the large pieces~ are removedl by rod' filtration. I'.f these pieces of entrained rr.atter are small enough, (l!ess tha^ 1um), thenit!iey exit the cigarette inithe smoke stream. Our development of a neutron radicgr- aphic facility at U.VA. now can be used to ilnvestigate this entraiinc!ent process. Dr. D. M. Smith of the University of ^few, '-Iexico at the AAAR meet- ing described tii~s techniques for preparing,monod!ispersed silica microspheres in the size rang,e of 0.01 to 1lum. He also: statedlto: me that in collabor3- tion with researchers at the Lovelace Research Foundlati~on, they have produced these same spheres coated with gadolinium (G'di) and with Gd centers. These spheres are relatively chemically inert. l•!e have pioneered the use of gadolinium as a contrast agent for neutron rad'iogrophic studies. Now, with these new discoveries by Dr. Smith, we should be able to prepare th~ese silica oarticles coated~ with Gd or have Gd included'withi!n spheres of' the right aerod'ynamic size to exit the cigarette. These spheres are of a nar- ro•.w, but controll~able size range just right for our studies. These small (ideally 0.1 to ©.4'um) spheres can then be encapsulated into a larger microcapsule whichl will rupture at a designed temperature and thus eject the Gd labelled microspheres into the mainstreaic:. Th~is will be covered in. dletail later. The addition of these multicomponent encapsulated materials to, tobacco and their locations can! be verifiled by neutron radio;raphy and neutron activation using our capabilities at U.VA. Simultaneously, the insoluble Gd spheres wi'11' be fed' to hydroponic tobacco plants as a function of sphere size to investigate potential plamt uptake andlthe subsequent mechanical entrainment or lack of into mainstream smoke. T'his will helo answer whether we can obtain entrainment for materials internal to the leaf as.well as externally applied. This provides us with the neededlanallytical. capability of evaluating progress of deliberate entrainment ar.dlto, monitor necessary parameter changes to improve the rate of entrainment. The detailed research parameters are to be reg,ulated by the observa- tions obtained by neutron radiography and on neutron activation analysis showing the exact location of these Gd spheres during smoking and/or filtration. b.) Multi-Component EncapsuIation The other phase of research necessary and to be conducted simul- taneouslly by us is that of fabrication of the multicomponent mierocapsules. At a recent presentation by the Southwest Research, Institute wo:^king, under contract from Pt1 in the New Products areas, they dlescribed how they are ready to producz working quantities of rrilcroencapsulated materials of a: of chemical compositions. My impressions are that PM (Development) has been to; this point interested in microcencapsulating,primarily volatile flavors, i.e., menthol, water, etc. Southwest described two types of microencaosulated technioues.

-3- 1. One where a shell of primary capsulie wall materia'_ surrounds the de5ired flavor li'ke the leather on a baseball around the core. This shell is ruptured by mechanical, thermal or other means releasing the flavor. 2l: The other also has a shell, but also contai'ns microspheres of the desired flavor material mixed in the matrix of ae'di'tiionall shell compound. This i's similar to the suspension of an insoluble material in, a gel or in principle designed like a"Contac° cold capsule, but with the shell material also throughout the microspherPs. This phase of'research would necessitate the enlargement of our present contract with Sbuthwest Research in order to, prepare microencapsulated material.s as already described for neutron rad'iog- raphy and a multicomponent capsule containing,a shell material and support medium that undergoes low temperature rupture (about 150°C) and is insoluble in water. The internal microspheres (flavor components) would be composedd of selecte.diwater soluble, non-volatile desirable smoke flavors which have ther:^al stabilities in excess of about 22'5°C. The overall size of the comoletedlparticle cani be 50 to 2OO~,n_ These particles can be added to: tobacco filler by spraying, but a preferred method was one I described in an earlier new idea disclosure, that of direct air injection through thee cigarette paper. This is the same technique normally used for mass popula- tion inoculations by firing a small vaccine aerosoli directly through the. skin. This would alloa the encmpsulated material desposition to be regu- latred just under, the cigarette paper, on the tobacco perpheriphy which we have shown to contribute heavily to the mainstream particulate phase. (Also. allowing one tobdcco filler to be used on a maker allowing one to change too the desired' flavor after the rod' is formed and before the ci,(7arette is cut . to length). The desired multicomponent microparticles would be attached too the tobacco and during,smoking as the rapidly moving thermal gradient ap- proached, the "lowtemperature" shell material would rupture ejecting thee hiigher temperature secondary non-volatile flavor (less than 0.4pm) spheress irrto,the moving smoke stream of a:puff. They should move toward the butt, and (if composed of the proper size range) be delivered out of the cigarette rod at a sufficiently high transfer rate. These flavor particles being, water soluble would be: immediately aivaillaMle for sensory effects to the smoker. They may also grow due to the normal condensation processes, butt based on our neutron, r3diograDhy results, the proper initial size range can be chosen to allow, sufficient partici~es to exit in the smoke. Because of the non-polar shell, these multicomponent micro:cap:s:ules would have th!e advantage of having,a long te,rm storage capability in the ci;arette without degradation by cigarette moisture or exhibit any unfavorable migration. The two experimental approaches are merged at this point as follows: a.) Southwest is requested to mi'lcroencapsulate the insolubie Gadoliniuc: coated silica.particles with the same shell material as usedli,n the emperi- ca1 multicomponent system. Using,neutron radiography and neutron activation the fate of the secondary micronpheres can be :nonitored and proper scien- tific explanations and r.:odifications to our transfer system"mad'e.

-u- This overall proposal is blessed with; a very important desibni criteria. Regardless of the results obtained using,our multicomponlent microcapsul-cs contaiininJ the non-volatile flavor„ definite quantitative measurement's of the locsti'on and concentration of the identical'. sized spheres containing the. Gadolini~um-silicate mixture can be monitored'.. This would enable us to change experirental parameters and monitor their effects on th secondary flavor oarticle smoke transference. Without the neutron analytical tech- nie,,ues, this experir~ental approach would be ini the dark andi proceed only by long trial and error as have many of our earlier stu~dies at PM; on flavor transfer. The second new product idea evolves ?round the saime multicomponent pairti'cle conceot in a"'smokPless" cit-arzttp. In a recent staff ineeting,you rrqwested su;;gestions as how to design, a better product than the product "Favor" . Using our multi-component microcapsules„ one could place these on, an, inert substrate within a cylinder like a ciigarette. Using current tech- nology, the normal moisture in air or that released by crushing a designated end'containing water capsules with fingers, water varnor co:uld.be drawn through the rod'by puffing. There is tec:hnology present to take this water vapor, react it t•nith, materials known to be exothermic wiith water, rel'easinig low temperature heat which would then rupture the shell material of the miicrocapsules thereby releasing the secondary flavor sph!eres of'the size to be drawn out of the,device as in the case described already for cigarettes. These secondary spheres could contain desired cigarette f'lavors/compounds,, being delivered to the consumer Ini an aerosol not in a vapor state as is done by "Favor". This would! more closely mimic actual cigarettA smoke. This subject can be pursued further if you wish and I think with the proper smoke components, this product wouldlcontain many desirable charac- teristics for a smokeless product. In both the deliberate entrainment in ciga~ette smoke and the smokeless device, there woul'd be expected to also bee some non-volatiilie flavor transfer to the sidestream, perhaps also improving flavor characterilstics. To implement this program would require a minimum disruption to our curremt studies. The folllowing,comes to immediate attention: t.) The same personnel and equi'pment presently used' at ?NI: and at the Nuclear Eng. Dept. of U':.Va. can be usedl to support all N'AA and' radiographic measurements with li,ttle, if' any increases in moniles and no increase in personnel., 2.) All PM personnel necessary to form the research team are presently worki;ng together in the Chemical Research Division (D. McRae, R. Newman, R. B'ass, G. Newell, ii. Grubbs and R. Jenkins,). These personnel could conduct all experimental'work necessary to the new, fflavor transfer technique. N 0 I would'be glad to serve as scientific coordinataor for the feasibility studlies and make all necessary ou~tside support and/or consultant w arrangements. ~ ~ 3.) The existing contract with Southwest Research could be utillized ~ with modest increases in cost to prepare the experimental samoles. Opp 0

-5- 4. ) Consulting arrangements„ if nece.ssa.rv„ may be needed with Dr. Smith or an appropriate expert. The potential for PM having , sucha a truly distinctive an:d novel flavor transport system is immense. This wouild'not be a.slight enhancement to conventional cigarettes as conductedlin all past flavor enrichment programs, but a totally new product that shouldlproduce unknown distinctive subjectiive, results. The smokeless cigarette approach would surely be a definite im- provement over the current market product and go a long way in meeting the needs of this group of'consumers. All of this can be gained while making it extremely difficult for other companies to duplicate. Thils being because we are the.only research group that has a real-time neutron radiographic facility and just purely chemical analyses on our newly desiFned cigarettes would show the non-volatile flavors, but w,oul'd not answer how they are transferred. I welcome the opportunity to discuss thiS plan or to begin immediate scientifiic investi;at.ions. I estimate the feasibility studies to be com- pleted within about 2 years if we can aet Southwest or similar companies to prepare our test microcaosules in a proper timc frame. /ds cc: f,. Ferguson Pf . K. C. Hausermann HOuohton Lillly