Патент USA US3057761код для вставки
United States Patent O??ce 1 2 what higher and somewhat lower ignition temperatures 3,057,757 may be used. The ignition may be carried out in the presence of air or other oxidizing atmosphere. The No Drawing. Filed Feb. 12, 1960. Ser. No. 8,242 alumina is ground to provide a ?nely divided material, i.e., a material which is substantially all ?ner than 325 mesh. The tobacco I employ is conventional leaf tobacco of the type used in cigars, cigarettes or pipes. It is reason SMOKENG COMPQS‘ITEONS AND SMOKING UNlT CGNTAINING SAME Charles G. Albert, Basking Ridge, N.J., assignor to Min erals & Chemicals Philipp Corporation, Menlo Park, Ni, a corporation of Maryland ‘ 3,057,757 Patented Oct. 9, 1962 7 Claims. (Cl. 131-17) able to expect that reconstituted tobacco or mixtures of The present invention relates to smoking mixtures con 10 tobacco leaf and reconstituted tobacco may be used. . In putting my invention into practice, the alumina taining tobacco mixed with a ?nely divided solid material and to smoking units, especially cigarettes, containing the powder obtained by grinding decomposed aluminum nitrate is uniformly mixed with shreds of tobacco in amount of about 1 to 20 percent, and more preferably about 5 to 15 percent, based on the tobacco weight. Any 15 tobacco therein burns with an appreciably reduced tar method of uniformly dispersing the alumina on the content and the tobacco smoke is characterized by a tobacco particles may be used. The additive may be smooth, pleasant aroma and taste. applied by dusting the dry material on the tobacco, by The desirability of reducing the tar content in the spraying a dispersion of the additive in a liquid or gaseous mainstream of tobacco smoke, that the smoke passing through the mouth end of a smoking unit, is well-rec 20 carrier or by other means which will readily suggest them selves to those skilled in the art. Alumina which is very ognized. Tar from tobacco smoke is believed to be in ?ne, such as 10 microns or less, will usually adhere well jurious to health and produces discoloration of the teeth. to the tobacco without an adhesive. However, if dc‘ Most attempts in the past to reduce the tar content of sired, an adhesive, inorganic or organic. may be employed smoke have centered on the use of a porous ?ltering 25 to secure the alumina particles to the tobacco. means integral with and forming an end of the smoking Preferably, the tobacco to which the solid alumina is unit. applied is in a form suitable for direct use in the cigarette I have discovered that when a small amount of a unique or other smoking article for which it is intended, namely, amorphous form of alumina, hereafter described, is mixed tobacco which has been aged, shredded, humected and directly with smoking tobacco, the quantity of tar normally produced by the tobacco and passing into the 30 treated with ?avoring agents and such other tobacco-treat ing materials as may be desired. mainstream smoke is signi?cantly reduced. same. The invention has for its principal object the pro vision of a smoking mixture of such a character that the Brie?y stated, tobacco compositions of the present in vention comprise a uniform mixture of tobacco with a A ?lter tip integral with the column of the mixture of alumina and tobacco shreds may, if desired, form the mouth end of a cigarette of my invention. The ?lter tip small quantity of ?nely divided relatively dense alumina 35 may contain ?ne ?bers or it may contain other micro which is produced by thermal decomposition of aluminum nitrate. When such a tobacco composition is smoked, the amount of tar is reduced from that produced by the porous materials as are used in a ?lter tip for a cigarette. The ?lter tip in a cigarette of the present invention will serve a plurality of important functions. It will supple same weight of tobacco but in the absence of the alumina. The alumina is innoxious and has no harmful effects on 40 ment the tar reduction realized through the use of the alumina and it will prevent ?nely divided alumina parti the smoker even if it passes into the smoker’s mouth. It has been found that aluminas produced by thermal cles from passing into the smoker’s mouth. The following examples are given to illustrate more fully my invention. class, the ability to reduce the tar content of tobacco Tests were conducted to demonstrate that the total smoke. It has also been found that many forms of 45 quantity of tar passing into the mainstream of the smoke alumina such as, for example, bauxite (alpha-alumina decomposition of aluminum salts do not possess, as a trihydrate) and alumina thermally produced by the thermal activation of bauxite are ineffective for the pur pose, even when used in quantities in which the alumina produced from aluminum nitrate is eminently effective. The ‘reason for this phenomenon is not presently under stood, especially since the alumina from aluminum nitrate has a relatively low BET. surface area, typically about 57 from a given weight of cigarette tobacco is signi?cantly reduced by mixing the tobacco with the amorphous alumina which is produced by ignition of aluminum nitrate. Similar tests were conducted to show the be 50 havior of other aluminas with-the same tobacco. was placed in a muffle furnace held at 1400° F. for 2 square meters per gram, Whereas some forms of alumina hours and cooled. The calcined product was then ground which are ineffectual for the purpose have much higher 55 to 100 percent finer than 325 mesh. The product was a surface areas and would be expected to be superior white powder having a B.E.T. surface area of 56.88 square sorbents for tars. This indicates that factors other than meters per gram and consisting of an amorphous sub tar sorption account for the effectiveness of the alumina stantially pure form of alumina. from aluminum nitrate in reducing the tar content of A blend of Turkish and domestic cigarette tobacco tobacco smoke. 60 supplied under the trade name “Bugler” was used in all The starting material I employ in the preparation of of the smoking experiments. the alumina is aluminum nitrate or any of its hydrates. Experimental cigarettes were prepared by uniformly The aluminum nitrate is heated at a temperature and dry mixing 100 parts by weight of the tobacco shreds with for a time su?icient to eliminate completely the nitrate, 10 parts by weight of the alumina powder prepared from leaving a white, rather dense mass, the particles of which 65 aluminum nitrate and packing about 0.99 gram of this are amorphous when investigated by conventional X-ray mixture containing about 0.90 gram of tobacco into a diffraction procedure. Heating the nitrate at tempera tures of the order of about 1400° F. for about 1 to 2 hours will su?ice to decompose the nitrate, although some cigarette paper wrapper. The weight of the cigarette wrapper was approximately 60 milligrams. Control 3,057,757 3 4 cigarettes containing about 090 gram of the Bugler tobacco per cigarette were prepared. The smoking tests were repeated using tobacco mixed with various quantities of other ?nely divided aluminas. It was found that the tar yield of cigarettes containing alpha-alumina trihydrate in the amount of 10 percent of Also made up were cigarettes containing a mixture of 100 parts of Bugler tobacco and 10 parts by weight of alumina produced by calcining aluminum tartrate at 1400“ F. for 2 hours. All 5 the tobacco weight was a 2 percent increase over the tar cigarettes were conditioned at 24° C. and 58 percent R.H. yield of control cigarettes. The mixture of alpha before smoking. alumina trihydrate with tobacco in the amount of 5 per All cigarettes were mechanically smoked by the method cent of the tobacco weight increased the tar yield by 11 described in detail in Industrial and Engineering Chem percent. Five percent of activated bauxite, based on the istry, vol. 28, No. 7, in an article entitled “Nature of 10 tobacco weight, decreased the tar yield by only 2 percent. Cigarette Smoke-Technique of Experimental Smoking,” I claim: J. A. Bradford et al., pp. 836-839 (1936). 1. A smoking mixture comprising tobacco having Cigarettes were smoked individually employing a con mixed therewith a small amount of alumina which is pro stant puff of about 2 seconds’ duration once each minute duced by thermal decomposition of aluminum nitrate. and with sut?cient puffs to leave abutt of about 22 mm. 15 2. A smoking mixture comprising tobacco shreds hav The smoke from 5 cigarettes of a given composition was ing uniformly mixed therewith a small amount of ?nely collected in a glass-wool trap packed to give 40 cm. water divided alumina which is produced by thermal decomposi pressure drop at the ?ow rate of 1050 cc. of air per tion of aluminum nitrate. minute. The trap was shown to collect at least 95 per 3. A smoking mixture comprising tobacco shreds hav cent of the nonvolatile components of the smoke. The 20 ing uniformly mixed therewith from 1 to 20 percent by trap was evacuated for 20 minutes and weighed. The weight of alumina which is produced by thermal decom weight increase divided by 5 was reported as the milli position of aluminum nitrate. grams of tar per cigarette. 4. A cigarette comprising shreds of tobacco in columnar The results reported in the table represent the average arrangement enclosed in a paper wrapper, said shreds of three determinations, each determination representing ‘25 being uniformly mixed with a small amount of ?nely the result of smoking 5 cigarettes of the reported com divided alumina which is produced by thermal decomposi position. tion of aluminum nitrate. These results show that the alumina produced from 5. The cigarette of claim 4 including a ?lter tip in aluminum nitrate was highly effective in reducing the tar tegral with the shreds of tobacco and forming one end content of the cigarette smoke and that the alumina made 30 thereof. from aluminum tartrate was only about one-third as effec 6. A cigarette comprising shreds of tobacco in columnar tive as the alumina from aluminum nitrate. Also shown arrangement enclosed in a paper wrapper, said shreds is that the alumina from aluminum nitrate had little ob being uniformly mixed with from 1 to 20 percent by servable effect on the burning rate of the tobacco since weight of ?nely divided alumina which is produced by about the same number of puffs left about the same 35‘ _ thermal decomposition of aluminum nitrate. length of butt in the control cigarette and the cigarette 7. The cigarette of claim 6 including a ?lter tip inte gral with the shreds of tobacco and forming one end thereof. prepared with alumina produced by ignition of aluminum nitrate. The Effect of Mixing Finely Divided Aluminas Produced by Ignition of Aluminum Salts With Cigarette Tobacco on the Total Tar Content of Cigarette SmOke Average Composition of Cigarette Average Pressure Average Average Average Wt. of Drop No. of Butt During Putts Length, Tars Per Cig., Percent Cig., gm. Smoking mm. mg. tion Tar Reduc' cm. H2O Control Cig. (no alumina)- 0.9464 4.5 9.4 21.9 34.9 ........ ._ Aluminum Nitrate 1---. 1.0238 5.7 9.6 21.5 28.9. 17.1 Aluminum Tartrate 2--. 1.0237 5.3 9.6’ 20. 9 32. 7 6.3 Cig. Containing 10% 1 Alumina from Ignited Cig. Containing 10% 1 Alumina from Ignited 1 Based on weight of tobacco. 3 Ignited at 14000 F./2 hr. References Cited in the ?le of this patent UNITED STATES PATENTS 1,652,119 2,007,407 2,839,065 2,933,420 2,938,818 2,941,906 Halvorsen et a1. _______ __ Dec. 6, Sadtler _______________ __ July 9, Milton _______________ __ June 17, Haden _______________ __ Apr. 19, Specht _______________ __ May 31, Hadin _______________ __ June 21, 1927 1935 1958 1960 1960 1960 OTHER REFERENCES Aluminum and its Production (text) by Edwards, Frary and Jetfreis, vol. I (1930), published by the McGraw Hill Book Co. Inc., N.Y., 358 pp. Pages 124-280, inclu sive, especially cited. Copy in Division 3.