KR20070017579A - Tobacco smoke filter - Google Patents

Abstract

The present invention relates to copper containing porphyrins or C.I. A tobacco smoke filter comprising an iron analog of the reactive blue 21 dye. In addition, the present invention provides a method for producing a polymer comprising: providing one or more materials; Producing a mixture of cellulose fiber, sodium sulfate, chlorine water and the substance; Heating the mixture for a sufficient time at one or more temperatures sufficient to covalently bond material to the cellulose fibers; And forming the covalently bonded cellulose fiber into the first tobacco smoke filter segment. The material may be copper containing porphyrin or C.I. Iron analog of the reactive blue 21 dye.

Description

Tobacco Smoke Filter {TOBACCO SMOKE FILTER}

Tobacco smoke is well known to contain mutagenic and carcinogenic compounds which cause significant morbidity and mortality in smokers. Examples of such materials are polycyclic aromatic hydrocarbons (PAH) and nitrosamines.

Polycyclic aromatic hydrocarbons are believed to be toxic by intercalation within the DNA molecule. Nitrosamines are electrophilic alkylating agents and are potent carcinogens. Nitrosamines are not present in live tobacco and do not form during combustion. Instead, these substances are formed by reactions involving free nitrates during processing and storage of tobacco, or by metabolic activation after inhalation of secondary amines present in tobacco smoke.

Attempts to reduce the amount of toxic and mutagenic compounds reaching the smoker include placing a cigarette smoke filter between the burnt cigarette and the smoker. Conventional filters consist only of cellulose acetate or of cellulose acetate and activated carbon. However, such conventional filters are only partially effective in reducing the amount of toxic and mutagenic compounds reaching the smoker. In addition, conventional filters disadvantageously reduce the acceptance rate by smokers by removing flavor compounds.

Therefore, there is a need for an improved smoking device filter that substantially removes toxic and mutagenic compounds from tobacco smoke. In addition, there is a need for improved filters that substantially pass away toxic and mutagenic compounds from tobacco smoke while passing the flavor compounds. It would be desirable for such an improved filter to be made simple and inexpensive and convenient to use.

The present invention relates to a tobacco smoke filter that meets the above requirements. In one embodiment, a method of making a first tobacco smoke filter segment is provided. The method first includes providing at least one copper containing porphyrin. Thereafter, a mixture of cellulose fibers and copper containing porphyrin is produced. This mixture is then heated for a sufficient time at one or more temperatures sufficient to covalently bond the copper-containing porphyrin to the cellulose fibers. Thereafter, the cellulose fiber covalently bonded with the copper-containing porphyrin is formed into a first tobacco smoke filter segment.

In one embodiment, the copper containing porphyrin provided is copper phthalocyanine. In one preferred embodiment, provided copper-containing porphyrins are selected from C.I. Reactive Blue 21 dye. In yet another embodiment, the resulting mixture of cellulose fibers and copper containing porphyrin comprises a copper to porphyrin to cellulose fiber in a weight ratio of about 1.2: 10. In one preferred embodiment, the mixture of cellulose fiber and copper containing porphyrin further comprises sodium sulfate and chlorine free water.

In one embodiment, the method further comprises washing the mixture covalently bonded to the copper-containing porphyrin and cellulose fibers after heating the mixture. In yet another embodiment, the method further comprises adding one or more additional materials to the cellulose fibers covalently bonded with the copper containing porphyrin. In one embodiment, the one or more additional substances are selected from the group consisting of activated carbon, chitin and lignin. In another embodiment, the one or more additional materials are selected from the group consisting of antioxidants, dry water, wetting agents, microcapsules, radical scavengers, surfactants, and combinations thereof.

According to one embodiment, a method of manufacturing a smoking device is provided. The method includes first providing a first tobacco smoke filter segment made in accordance with the present invention and then attaching the first tobacco smoke filter segment to the body of divided tobacco. The method may further comprise attaching a second tobacco smoke filter segment substantially free of copper containing porphyrin to the body of divided tobacco. In one preferred embodiment, the second tobacco smoke filter segment attached to the body of divided tobacco comprises cellulose acetate fibers treated with triacetin.

According to one embodiment of the present invention, there is provided a tobacco smoke filter comprising a first tobacco smoke filter segment made in accordance with the present invention. Such tobacco smoke filter may also include a second tobacco smoke filter segment that is substantially free of copper containing porphyrin. According to yet another embodiment, there is provided a smoking device comprising a tobacco smoke filter according to the invention attached to a body of divided tobacco.

According to one embodiment of the present invention, a method of filtering tobacco smoke is provided. The method comprises the steps of providing a smoking device according to the invention, igniting the body of divided tobacco such that the smoke passes through the body of divided tobacco and into the filter, and passing the smoke through the filter to filter the smoke It includes.

The present invention is directed to C.I. Further comprising an iron analog of the reactive blue 21 dye, C.I. Further provided are the method, tobacco smoke filter and smoking device of the present invention wherein an iron analog of the reactive blue 21 dye is used in place of the copper containing porphyrin.

According to one embodiment of the invention, a filter for tobacco smoke is provided. Such a filter may be provided in combination with a cigarette or cigar or other smoking device containing split tobacco. Preferably, the filter is secured to one end of the smoking device in a form that is arranged to be delivered into the filter before the smoke generated from the cigarette enters the smoker. The filter may also be provided by itself in a form suitable for attachment to a cigarette, cigar, pipe or other smoking device.

The filter according to the invention advantageously removes significant amounts of mutagens and carcinogens from cigarette smoke. The filter of the present invention further possesses satisfactory or improved smoke flavor, nicotine content and draw characteristics. The filter of the present invention is designed to be acceptable to the user, so it is not cumbersome or unattractive as a commercial filter designed to be added to the end of a pre-made cigarette. In addition, the filters according to the invention can be made with inexpensive, safe and effective components and can be made with only minor modifications to standard cigarette making machinery.

According to one embodiment of the invention, the filter comprises a porous substrate. The porous substrate can be any non-toxic material suitable for use in filters for smoking devices that are also suitable for combining with other materials according to embodiments of the present invention. Such porous substrates include cellulose fibers such as cellulose acetate, cotton, wood pulp and paper; And polyesters, polyolefins, ion exchange materials, and other materials that are understood by one of ordinary skill in the art by reference to this specification.

Filter containing wetting agent

According to one embodiment of the invention, the filter comprises one or more wetting agents alone or in combination with other materials described herein. Wetting agents can wet filter the tobacco smoke passing through the filter by absorbing moisture from the tobacco smoke and releasing it into the porous substrate. Among other advantages, the wet filtration system according to the present invention assists in removing particulate matter from tobacco smoke and can be manufactured integrally with tobacco containing products.

Wetting agents may be any suitable wetting agents. For example, wetting agents include glycerol, sorbitol, propylene glycol, sodium lactate, calcium chloride, potassium phosphate, sodium pyrophosphate or sodium polyphosphate, calcium citrate, calcium gluconate, potassium citrate, potassium gluconate, sodium tartrate , Sodium calcium tartrate and sodium glutamate.

In one preferred embodiment, the humectant incorporated into the filter is sodium pyroglutamate (also known as sodium 2-pyrrolidone-5-carboxylate or NaPCA). Advantageously, sodium pyroglutamate is non-toxic, effective in removing charged particles from tobacco smoke, and functions as a humectant in the temperature range of tobacco smoke. In addition, it is non-hazardous, stable, simple to manufacture and convenient to use. Sodium pyroglutamate has the following structural formula:

The filter according to the invention is produced simply and inexpensively. In one method of preparation, a solution containing a humectant, such as sodium pyroglutamate, is prepared. Thereafter, the porous substrate is wetted with the solution. The wet substrate is dried to disperse the residual wetting agent on or in the porous substrate. In one preferred embodiment, the humectant is present in an amount from about 5% to about 60% based on the dry weight of the filter.

The effectiveness of the tobacco smoke filter containing sodium pyroglutamate according to the present invention was tested as follows.

Three types of filters were tested for their relative effectiveness in removing tar from cigarette smoke:

1) conventional cellulose acetate filter ("Cell-Ac");

2) a wet filtration tobacco smoke filter according to the invention containing cellulose acetate and sodium pyroglutamate ("SoPyro"); And

3) Commercial wet filtration tobacco smoke filter (Aquafilter®, Aquafilter Corp.)

A cellulose acetate filter containing sodium pyroglutamate was prepared by first separating the cellulose filter from commercial cigarettes. The weight of the fiber was about 0.21 g. Then, about 0.5 ml of sodium pyroglutamate 10% by weight solution was applied to each filter, and the filter was dried at 60 ° C. overnight.

Conventional cellulose acetate filters and cellulose acetate filters containing sodium pyroglutamate were weighed and inserted into 40 mm segments of polycarbonate tubing with an inner diameter equal to the outer diameter of a standard cigarette. A filterless cigarette with 0.85 g of tobacco was inserted into one end of the polycarbonate tubing at a location proximate to one end of the filter. The remaining end of the polycarbonate tubing was attached to the tubing connected to the suction pump. Each filter type was tested in duplicate. Each aqua filter used in the experiment was also attached to a filter-free cigarette with 0.85 g of tobacco and then to a tubing connected to a suction pump.

The filtered cigarette was lit and an intermittent suction was applied to simulate the inhalation of the cigarette smoke until the cigarette burned into 12.5 mm of the unburned end. The filter was separated from a polycarbonate tube or aqua filter, weighed, and placed in 10 ml of methanol to elute tar and fumes remaining from the filter. The absorbance (350 nm wavelength) of the ethanol-based filter eluent was used as an indicator of the amount of smoke component remaining in the filter. The weight of the filter stretched during the passage of the smoke was also recorded. The test results are shown in Table 1.

Table 1

exam filter Absorbance at 350nm Weight gain One Cell-ac 0.470 A.U. 35mg 2 Cell-ac 0.381 A.U. 30mg 3 SoPyro 0.731 A.U. 71mg 4 SoPyro 0.625 A.U. 60mg 5 Aqua Filter 0.540 A.U. * 6 Aqua Filter 0.560 A.U. *

The weight gain due to the absorption of the smoke component onto the aqua filter could not be measured because the aqua filter actually lost weight during the passage of the smoke, possibly due to the evaporation of moisture.

Based on the absorbance data, filters according to embodiments of the invention (tests 3 and 4) are much more effective than conventional cellulose acetate filters (tests 1 and 2) without wetting agents, and aqua filters (tests 5 and 6). More effective than

Filter containing dry water

According to another embodiment of the present invention, a filter is provided for wet filtering tobacco smoke, including "dry water", with or without other substances described herein. Dry water is a combination of methylated silica and water. In one embodiment, the methylated silica is present in an amount of about 5% to 40% by weight and water is present in an amount of about 60% to 95% by weight. In one preferred embodiment, methylated silica is present in an amount of about 10% by weight and water is present in an amount of about 90% by weight. Advantageously, dry water has good stability when used in filters according to the invention. In addition, it is inexpensive, nontoxic and not harmful to the environment.

In one preferred embodiment, the dry water is present in an amount from about 1% to about 20% by weight based on the filter. In one particularly preferred embodiment, dry water is present in an amount from about 5% to about 10% by weight based on the filter.

Dry water used in the present invention can be prepared, for example, by shaking excess water and methylated silica in a closed vessel until an equilibrium emulsion is obtained. The excess water is drained off and a desiccant, such as underivatized silica, is added in an amount corresponding to 10% of the amount of methylated silica in the emulsion. The emulsion is further shaken to disperse the desiccant.

One problem associated with the use of dry water in cigarette smoke filters is that when dry water is present as a continuous layer between cigarettes and smokers, it prevents air gaps in the filter, increasing resistance to airflow and reducing the pleasure of smoking. There is a tendency. In order to solve this problem, an embodiment of the present invention having dry water mixed with loose fibrous material is provided. This additional fibrous material provides scaffolding, which reduces the firmness of the silica particles into the filter material when smokers inhale. Examples of such materials are cellulose or cellulose acetate with a fiber length short enough for dry water to behave as a flowable powder. In one preferred embodiment, the fiber length is less than about 1 mm. In one preferred embodiment, the tobacco smoke filter according to the invention comprises both porphyrin as well as dry water as discussed herein. For example, a tobacco smoke filter according to the present invention comprises a section of about 3 mm to 6 mm filled with dry water, chlorophyllin and cellulose in the filter or at the distal end of the filter between conventional filter material and tobacco. Tobacco smoke in these filters passes through dry water and porphyrin which retain carcinogenic smoke components in the dry water and chlorophyllin layers.

Tobacco smoke filters according to this aspect of the invention can be prepared by adding a dry water and porphyrin mixture during the manufacture of the filter, or by injecting the mixture into the filter or at the interface between the tobacco and the conventional filter. The dry water and porphyrin mixture may be injected into the axial end of the filter, or through the side of the smoking device, for example, via a cannula attached to the injection device. Preferably, the infusion device measures the amount of substance administered per each infusion.

Alternatively, the dry water and porphyrin mixture may be included in the filter extension for attachment by a smoker to a conventional smoking device such as a standard cigarette or a cigarette filter. The filter extension comprises a layer of dry water and porphyrin and preferably comprises a fibrous material as matrix. The filter extension further includes a sleeve extending axially forward to fit with the proximal end of the smoking device. The sleeve is in contact with the porous retaining element to keep dry water and porphyrin in the filter extension. Preferably, the sleeve further comprises a length of conventional filter material such that when connected to the smoking device the filter extension and the smoking device are considered substantially conventional smoking devices.

Filter containing copper-containing porphyrin

According to another embodiment of the present invention, there is provided a cigarette filter comprising one or more porphyrins, such as chlorophyll, in the presence or absence of other materials described herein. Preferably, porphyrins are copper containing porphyrins such as chlorophyllin and copper phthalocyanine trisulfonate (copper phthalocyanine, copper phthalocyanate).

Porphyrins are two-dimensional compounds that inactivate many classes of mutagenic and carcinogenic substances. Porphyrins inactivate two-dimensional mutagenesis and carcinogens by binding carcinogens to two-dimensional porphyrin structures, primarily through hydrophobic interactions. Thus, porphyrins ideally need to be maintained in an aqueous environment to optimally adsorb such tobacco smoke carcinogens. Porphyrins deactivate carcinogens by binding to polycyclic aromatic hydrocarbons (PAH) via π-π (pi-py) bonds. Copper-containing porphyrins also inactivate many types of non-dimensional mutagenic and carcinogenic substances, including some nitrosamines, through reaction with copper ions. Although it is known to inactivate a variety of carcinogenic substances, there is no known method for effectively using porphyrin in cigarette smoke filters.

Chlorophyllin is a natural copper-containing porphyrin and is a stable form of chlorophyll in which magnesium in chlorophyll is substituted with copper. Chlorophyllin has the formula:

However, chlorophyllin is difficult to chemically bond to tobacco smoke filter components. Thus, in one preferred embodiment, the copper containing porphyrin incorporated into the tobacco smoke filter is copper phthalocyanine. Copper phthalocyanine is a nontoxic synthetic chlorophyllin analog that can be bound more easily to tobacco smoke filter components than chlorophyllin. Copper phthalocyanine has the formula:

In one embodiment, copper containing porphyrins, such as copper phthalocyanine, are incorporated into the tobacco smoke filter by adding copper containing porphyrin directly to the tobacco smoke filter. In one preferred embodiment, the copper phthalocyanine is a ligand covalently bonded to a cotton such as a fabric dye "blue cotton" or a ligand covalently bonded to a rayon such as "blue rayon", Or can be incorporated into tobacco smoke filters as ligands covalently bonded to other suitable materials to those skilled in the art with reference to the specification. In another preferred embodiment, copper phthalocyanine can be incorporated into tobacco smoke filters in a form combined with other tobacco smoke filter embodiments of the present invention.

The copper-containing porphyrin is preferably a vinyl of copper phthalocyanine trisulfonate, as described in Hayatsu, Journal of Chromatography, 597: 37-56 (1992), which is hereby incorporated by reference in its entirety. CI as a sulfone derivative Attached to cellulose fibers in the form of active reagents, called reactive blue 21 dyes, which, under mild conditions (unlike chlorophyllin), form stable ether bonds with free hydroxyl groups on cellulose fibers to form "blue cellulose" or Form out material.

Cellulose is the base material used to make tobacco smoke filters. The standard form of cellulose used to make tobacco smoke filters is cellulose acetate fibers produced by treating cellulose with acetic anhydride. This reaction replaces the free hydroxyl groups present on the natural cellulose with more hydrophobic acetate groups. The cellulose acetate is then treated with triacetin (glycerol triacetate), a solvent that binds together a portion of the cellulose acetate fiber, because unlike cellulose, cellulose acetate is partially soluble in triacetin. Disadvantageously, however, substitution of hydroxyl groups with acetate groups and treatment of cellulose with triacetin significantly reduces the number of potential attachment sites to copper-containing porphyrin molecules and triacetin-treated as a base material for tobacco smoke filters. Make cellulose acetate less desirable than untreated cellulose.

Thus, according to one embodiment of the invention, there is provided a tobacco smoke filter comprising at least one segment, ie at least a first segment. The first segment comprises copper containing porphyrin and cellulose that has not been treated with acetic anhydride or triacetin. Preferably the tobacco smoke filter further comprises a second segment comprising cellulose acetate treated with triacetin but substantially free of copper containing porphyrin.

In a preferred embodiment, the copper containing porphyrin in the first segment is present in an amount from about 0.1% to about 5% based on the dry weight of the covalently bonded filter. In a particularly preferred embodiment, the copper containing porphyrin in the first segment is present in an amount from about 1% to about 3% based on the dry weight of the filter.

In one embodiment of the invention, there is provided a smoking device comprising a body of divided tobacco attached to a tobacco smoke filter comprising a first segment. Preferably, the smoking device comprises a first segment adjacent the body of divided tobacco and an adjacent second segment at the proximal end of the smoking device. This configuration allows the user of the smoking device to draw smoke directly through the second segment of the cigarette smoke filter so as to obtain a normal sense while using the smoking device.

In another embodiment of the present invention, a method of making a tobacco smoke filter disclosed herein is provided. The method produces a tobacco smoke filter comprising copper containing porphyrin, for example copper phthalocyanine, which tends to stay uniformly dispersed in the filter as the moisture accumulates in the filter during the manufacturing process and during the combustion of the cigarette, There is a tendency to not leak out of the filter during use.

The method includes preparing a filter material from cellulose or other materials, wherein one or more copper containing porphyrins are covalently bonded to the material. The filter material is then made of a tobacco smoke filter comprising a covalently bonded copper containing porphyrin and one or more segments of such material. In addition, the tobacco smoke filter may comprise one or more segments of a material substantially free of copper containing porphyrin. The use of filter material comprising covalently bonded copper containing porphyrins allows for the rapid production of large quantities of smoking devices, such as cigarettes, comprising a filter according to the invention using existing devices.

The method first comprises providing at least one copper containing porphyrin, for example copper phthalocyanine. In a preferred embodiment, the copper-containing porphyrin is a vinyl sulfone derivative of copper phthalocyanine sulfonate tree, such as CI Reactive Blue 21 dye (ORCO ^® REACTIVE Turquoise RP, Organic Dyestuffs Corporation, East Providence, available from RI US).

The amount of material given in the steps below is relative and is merely exemplary. The amount will be adjusted up for commercial production as will be apparent to those skilled in the art with reference to the present application. After providing copper containing porphyrin, about 10 g of cellulose of a grade suitable for use as, for example, about 1.2 g of copper containing porphyrin and paper pulp comprising a copper containing porphyrin to cellulose fiber in a weight ratio of about 1.2: 10. Create a mixture comprising the fibers. The mixture further comprises about 10 g sodium sulfate in about 200 mL of chlorine free water. The mixture was then heated to about 30 ° C. for about 35 minutes, after which the temperature was raised to about 70 ° C. for about 60 minutes to complete the covalent bonding of copper containing porphyrin to cellulose fibers. The mixture is then recovered on the mesh and washed thoroughly with running tap water to produce cellulose fibers with covalently bonded copper containing porphyrins. The cellulose fibers with covalently bonded copper containing porphyrins are then shaped into segments of tobacco smoke filters using commercially available equipment. The filter is then attached to the body of divided tobacco to produce a smoking device according to the invention. The present invention also includes paper impregnated with copper containing porphyrin prepared as above, which has a tobacco smoke filter or other use.

The method of making a tobacco smoke filter may further comprise adding one or more additional substances other than copper containing porphyrin to the tobacco smoke filter of the present invention. In a preferred embodiment, the at least one further substance is chitin, a polysaccharide derived from the shell of the arthropod, wherein the chitin particles are C.I. This is because it contains a high density of free hydroxyl groups that can be covalently bonded to a metal-porphyrin compound such as a reactive blue 21 dye. Based on dry weight, chitin is about four times more C.I. Covalently to the reactive blue 21 dye. In a preferred embodiment, chitin granules (available from Sigma Chemical Company, St. Louis, MO US) can be covalently bound to copper containing porphyrins in a manner equivalent to the reaction described above where cellulose is replaced with chitin. The amount of material given in the steps below is relative and is merely exemplary. The amount will be adjusted up for commercial production as will be apparent to those skilled in the art with reference to the present application. This is for example 0.8 g of C.I. Reactive Blue 21 dye and 6.8 g of sodium sulfate can be achieved by dissolving in 133 mL of distilled water. Thereafter, 2.0 g of chitin is added and the mixture is gently stirred at 30 ° C. for 20 minutes. Next, 2.7 g of sodium carbonate is added and the mixture is left at 30 ° C. for 15 minutes, and then heated from 30 ° C. to 70 ° C. over 20 minutes. The mixture is then stirred for 60 minutes while maintaining the temperature of 70 ° C. to complete the binding reaction. The resulting copper phthalocyanine-derivatized chitin is collected in a sintered glass filter and washed thoroughly with distilled water to remove unreacted dyes and salts.

Copper-containing porphyrin covalently bonded to chitin may be incorporated into paper by mixing the chitin-containing porphyrin to cellulose with cellulose pulp in a ratio of about 1:20 to about 1: 1 by dry weight. Can be. The cellulose may also comprise covalently bonded copper-containing porphyrins according to the present invention. Incorporation involves mixing the chitin with the cellulose pulp during the early stages of the papermaking process, while the cellulose is softening in water (prior to placing the pulp on a mesh and drying by compression). Chitin-impregnated cellulose can then be used for the production of tobacco smoke filters according to the invention.

In a preferred embodiment, the at least one additional component is activated carbon or lignin (a component of wood produced as a by-product of the preparation of cellulose paper pulp from wood). Either or both of these components can be added to the cellulose covalently bonded to the copper-containing porphyrin according to the invention, in particular for the production of papers incorporating activated carbon or lignin. Activated carbon or lignin, when present, is added to cellulose in the same manner and ratio as the chitin described above.

Also in a preferred embodiment, the filter produced as described above is attached to a tobacco smoke filter made of standard cellulose acetate fibers treated with triacetin to produce a filter comprising two or more segments. Preferably, the segment comprising cellulose acetate fibers treated with triacetin is adjacent to the segment comprising copper-containing porphyrin impregnated cellulose fibers, ie away from the lit end of the smoking device, and containing copper-containing. The segment comprising porphyrin impregnated cellulose fibers is between the segment comprising cellulose acetate fibers treated with triacetin and the body of divided tobacco.

The effectiveness of the two-segment filter prepared according to the invention was tested as follows. Tobacco smoke filters comprising two segments were prepared. Each proximal segment included cellulose acetate fibers treated with triacetin. The distal segment of one filter included the copper phthalocyanine impregnated cellulose fibers described above, while the distal segment of the remaining filters included cellulose fibers that were not treated with triacetin and not impregnated with copper-containing porphyrin. Next, the two-segment filter is placed in a plastic tubing leaving about a 0.5 cm tube without filter, and a 3 cm long tobacco rod of Marlboro ^® cigarette is inserted into a 0.5 cm empty end of the tubing facing the filter. To create a smoking device. The cigarette was set on fire and the smoking device was puffed 10 times with a suction pump until the cigarette burned and reached the end of the plastic tube. The filter was separated from the tube and placed in 10 ml of methanol containing ammonia at a dilution of 50: 1 to elute the retained polycyclic aromatic hydrocarbons from the filter. The 10 ml extract was evaporated to 1 ml and thin layer chromatography was performed on aluminum oxide using 5 ml hexane. The total polycyclic aromatic hydrocarbon content was evaluated by fluorescence photometer. As a result, the two-segment filter comprising copper phthalocyanine according to the present invention has 80ng of polycyclic aromatic hydrocarbons, while the two-segment filter containing no copper phthalocyanine has 6ng of polycyclic aromatic hydrocarbons. And it was found. This 13-fold increase is particularly important in that the total polycyclic aromatic hydrocarbons produced during the combustion of tobacco rods are estimated to be between 100 ng and 200 ng. Thus, the two-segment filter according to the present invention removed about 40% to 80% of the total amount of polycyclic aromatic hydrocarbons from tobacco smoke.

In another embodiment, the tobacco smoke filter of the present invention comprises an iron analog of copper-containing porphyrin but not copper-containing porphyrin. In one preferred embodiment, analogs are described in C.I. C.I. produced by acidifying the reactive blue 21 dye, adding iron sulfate and then adding a suitable base. Is an iron analog of the reactive blue 21 dye. Alternatively, iron salts such as anhydrous iron chloride can be used in C.I. During the initial synthesis of the reactive blue 21 dye, it can be used in place of the copper salts to produce iron analogs. In addition, C.I. The iron analogs of the reactive blue 21 dyes correspond to the copper containing porphyrin impregnated papers described above for use in preparing tobacco smoke filters or for other uses. It can be used to make paper impregnated with iron analogs of the reactive blue 21 dye.

Filter containing microcapsules

According to another embodiment of the present invention, there is provided a filter for tobacco smoke comprising a porous substrate having microcapsules dispersed therein with or without other materials described herein. The microcapsules preferentially comprise an inner core with an outer shell.

The core of the microcapsules contains one or more vegetable oils. Suitable vegetable oils include one or more oils selected from the group consisting of castor oil, cottonseed oil, corn oil, sunflower oil, sesame oil, soybean oil and seed oil. In a preferred embodiment, the vegetable oil is safflower oil. Other oils that are understood by those skilled in the art with reference to the present specification are also suitable. In a preferred embodiment, the vegetable oil is present in an amount of about 20 to about 80%, more preferably about 30 to about 70%, based on the dry weight of the microcapsules.

In a preferred embodiment, the microcapsule core also contains porphyrins such as chlorophyllin, or another porphyrin such as copper phthalocyanine. If present, chlorophyllin is preferably present in an amount of about 1 to about 10%, more preferably about 2 to about 5%, based on the dry weight of the microcapsules.

In a preferred embodiment, the microcapsule shell comprises a humectant. In a preferred embodiment, the wetting agent is sodium pyroglutamate, but other wetting agents that can be understood by those skilled in the art by reference to the specification can also be used. In a preferred embodiment, the wetting agent, such as sodium pyroglutamate, is present in an amount of about 10 to about 90%, more preferably about 20 to about 70%, based on the dry weight of the microcapsules.

In another preferred embodiment, the microcapsule shell also comprises methylcellulose. In a preferred embodiment, methylcellulose is present in an amount of about 5 to about 30%, more preferably about 10 to about 25%, based on the dry weight of the microcapsules.

In another preferred embodiment, the microcapsule shell comprises a polymer preparation such as polyvinyl alcohol or polyvinyl pyrrolidone, or comprises both polyvinyl alcohol and polyvinyl pyrrolidone in addition to or instead of methylcellulose. can do. In a preferred embodiment, the polymer formulation is present in an amount of about 2 to about 30%, more preferably about 5 to about 20%, based on the dry weight of the microcapsules.

The compounds used in the formulation of the microcapsules according to the invention can be obtained from several sources known to those skilled in the art, such as Sigma Chemical Co., St. Louis, MO US.

Microcapsules suitable for use in the present invention can be prepared according to various methods known to those skilled in the art. For example, the microcapsules according to the invention mix 200 g of vegetable oil with 500 g of an aqueous suspension comprising 25 g of low viscosity methylcellulose, 5 g of chlorophyllin, 50 g of sodium pyroglutamate and 150 g of corn starch. Can be prepared. This mixture is emulsified and spray dried to form microcapsules.

The microcapsules according to the invention can be formed by a spray drying method in the field of a tobacco production machine by spraying onto a sheet of tow before the cellulose acetate filter tow is formed into a cylindrical filter. Alternatively, suitable microcapsules may be prepared in advance and added to the sheet by dropping the microcapsules onto the cellulose acetate filter earth by means of a vibrating pan, or by other techniques which will be understood by those skilled in the art by reference to this specification. Can be. In addition, the microcapsules can be incorporated into a prefabricated filter by spraying the microcapsules onto the toe before the filter toe is rolled and formed into a rod of filter material.

As will be appreciated by those skilled in the art, the production of filters containing microcapsules according to the invention will require only minor modifications to conventional filter-tobacco manufacturing facilities. In addition, the production of filters containing microcapsules according to the invention is only slightly more expensive than conventional filters.

In use, the humectant portion of the microcapsules captures moisture from the tobacco smoke passing through the filter. Sodium pyroglutamate is particularly preferred because it can be incorporated into the filter in dry form.

When present, the oil portion of the microcapsules traps certain harmful volatile compounds, such as pyridine, without disturbing the flow of compounds that cause flavor and aroma. When present, chlorophyllin is a potent inert of carcinogenic components of tobacco smoke.

The methylcellulose portion of the microcapsules imparts structural stability to the microcapsules but disperses when exposed to water or warmed. Unlike the most commonly used viscosity imparting materials, methylcellulose precipitates out of warm solutions. It is also soluble at lower temperatures than the most commonly used viscosity imparting materials.

When a tobacco smoke filter containing a microcapsule comprising a shell of sodium pyroglutamate and methyl cellulose and a core of vegetable oil and chlorophyllin according to the present invention filters the tobacco smoke, the microcapsule captures heat and moisture from the tobacco smoke. . Methylcellulose precipitates into a fibrous material that increases the effective surface area available for wet filtration of tobacco smoke. This allows the moisture retained by sodium pyroglutamate to disperse quickly into the filter material. Chlorophyllin is distributed almost uniformly between aqueous and oil environments, increasing the inactivation of both particulate and vapor phase toxicity and mutagenic compounds of tobacco smoke than if chlorophylline is available in only one phase.

Filter containing surfactant

In another preferred embodiment, the filter of the present invention further comprises one or more surfactants to improve the effectiveness of the tobacco smoke filter, with or without the other materials disclosed in the present invention. In a particularly preferred embodiment, the surfactant is present in an amount from about 0.1% to about 10%, more preferably from about 0.1% to about 2% by weight of the filter.

Surfactants are preferably nontoxic and may include one or more of the following classes of compounds, although other suitable surfactants will be understood by those of ordinary skill in the art with reference to those disclosed herein: (1) Poly of sorbitan fatty acid esters Oxyalkylene derivatives (ie, polyoxyalkylene sorbitan esters), (2) fatty acid monoesters of polyhydroxy-alcohols, or (3) fatty acid diesters of polyhydroxyalcohols. Examples of suitable surfactants include ethoxylates, carboxylic acid esters, glycerol esters, polyoxyethylene esters, anhydrosorbitol esters, ethoxylated anhydrosorbitol esters, ethoxylated natural fats, oils and waxes, glycols of fatty acids Esters, polyoxyethylene fatty acid amides, polyalkylene oxide block copolymers and poly (oxyethylene-oxypropylene). Other suitable surfactants may also be used by those skilled in the art with reference to what is disclosed herein.

Filter containing additional substances

The filter may further comprise one or more other substances that filter or inactivate the toxic or mutagenic components of tobacco smoke. Examples of such materials include antioxidants and radical scavengers such as glutathione, cysteine, N-acetylcysteine, mesna, ascorbate and N, N'-diphenyl-p-phenyldiamine; Aldehyde inactivating agents such as en-diol compounds, amines and aminothiols; Ion exchange resins, nitrosamine scavengers such as chlorophyll and carcinogen deactivators; And nicotine collecting agents such as tannic acid and other organic acids. In one preferred embodiment, the filter comprises colloidal silica, which is a compound capable of scavenging secondary amines from tobacco smoke to inhibit the conversion of secondary amines to nitrosamines in the body. Other suitable materials may also be used as would be understood by one of ordinary skill in the art with reference to what is disclosed herein. In a preferred embodiment, the other materials are present in an amount from about 0.1 to about 10%, more preferably from about 0.1 to about 2% by weight of the filter.

Filters with Certain Combinations of Materials Disclosed herein

According to another embodiment of the present invention, there is provided a tobacco smoke filter comprising a combination of materials disclosed herein. In a preferred embodiment, the filter comprises a humectant, such as sodium pyroglutamate, in combination with dry water. This combination works synergistically to improve the wet filtration of tobacco smoke. In one embodiment, the filter comprises sodium pyroglutamate in an amount of about 1-20% based on the weight of the aqueous portion of dry water. In a preferred embodiment, the filter comprises sodium pyroglutamate in an amount of about 5% to 10% by weight of the aqueous portion of dry water.

In another preferred embodiment, the filter comprises a copper-containing porphyrin such as copper phthalocyanine with a humectant such as sodium pyroglutamate, dry water or both. Such a combination is particularly preferred because copper-containing porphyrins provide better cleaning of carcinogens in aqueous environments. In one embodiment, the copper-containing porphyrin comprises about 0.5% to about 5% by weight of dry water.

In another preferred embodiment, the filter comprises chlorophylline with humectant, dry water or both. In one embodiment, chlorophyllin comprises about 0.5% to about 5% dry water and the humectant comprises about 1% to 20% dry water.

A particular example of such a combination would be blue rayon (rayon impregnated with copper phthalocyanine) in combination with dry water. When present in an amount of about 10 mg to 100 mg at the 3 mm tobacco end of a standard cellulose acetate tobacco smoke filter, the combination does not impair aspiration, but mutagenicity of tobacco smoke is determined by the Ames test. It has been found to reduce by 75 to 80%. In addition, these components are inexpensive, safe and harmless to the environment.

The combination of dry water and porphyrin is produced, for example, by adding anhydrous porphyrin in an amount up to the amount of methylated silica relative to the dry water produced according to the present disclosure. Porphyrin should be added after dry water is stably emulsified. Dissolution of porphyrin in water prior to emulsification on methylated silica produces labile porphyrin / dry water compounds. In a preferred embodiment, porphyrin is added in an amount of about 0.1 to 0.5 grams per gram of methylated silica. In a similar manner a combination of dry water and porphyrin-derivatized fibers such as blue cotton or blue rayon is produced. After the combination of the two materials, the combination is shaken or stirred to be homogeneous.

Filter with circumferential barrier

The filter according to the invention is preferably provided with an external moisture-impermeable columnar barrier or casing to prevent it from getting wet by the smoker's hand. Such barriers can be prepared from polymeric materials such as ethylvinyl acetate copolymers, polypropylene or nylon, as will be appreciated by those skilled in the art.

Location of material in the filter

The materials described herein can be incorporated into the filters in various arrangements in accordance with the present invention. For example, the material (s) can be dispersed throughout the filter in a substantially constant manner. In addition, the substance (s) may be interspersed in only one segment of the filter, such as the proximal (end closest to the smoker) of the thirds, the middle of the third or the distal (ends closest to the cigarettes) of the third.

In another embodiment, one or more materials are interspersed in one segment of the filter and one or more other materials are interspersed in different segments of the filter. Two segments may have overlapping regions. For example, the filter according to the present invention may have dry water interspersed in the distal portion of the filter and copper-containing porphyrin interspersed in the distal portion of the filter. Also, for example, the filter according to the present invention has a sodium capsule dispersed in the proximal two-thirds of the filter and microcapsules scattered distal of the filter so that the two materials are not only overlapped in the overlapping region of the filter but also in the overlapping region of the filter. May have glutamate.

In another embodiment, the substance (s) can be incorporated into the filter and then attached to the end of the standard tobacco smoke filter. In a preferred embodiment, the substance (s) is incorporated into a tobacco smoke filter similar to the shortened variant of the standard tobacco smoke filter, which shortened filter is then attached to the end of the standard tobacco smoke filter. In this embodiment, the user will not be able to clearly identify the additional shortened filter due to its similarity in structure to the standard filter, unlike commercial filters added on the proximal end of the smoking device.

In addition, the material (s) according to the invention can be incorporated into the layer of the filter between the fibrous material constituting the remainder of the filter and the body of the separated tobacco.

Smoking device incorporating a filter according to the invention

According to another embodiment of the invention, there is provided a smoking device comprising a tobacco smoke filter as described herein attached to the body of divided tobacco. For example, the smoking device may be a cigarette incorporating a filter containing microcapsules with sodium pyroglutamate interspersed with a porous material.

How to filter cigarettes

According to another embodiment of the present invention, a method of filtering tobacco in a smoking device is provided. The method comprises first providing a smoking device comprising a tobacco smoke filter according to the invention attached to a body of divided tobacco. The body of divided tobacco is then ignited to allow smoke to pass through the body and into the filter. The smoke is then filtered by passing through the filter.

How to manufacture a smoking device

According to another embodiment of the present invention, a method of manufacturing a smoking device is provided. The method first comprises providing a tobacco smoke filter according to the present invention. Next, the filter is attached to the body of the divided tobacco.

Although the present invention has been discussed in detail with reference to certain preferred embodiments, other embodiments are possible. Therefore, the spirit and scope of the appended claims should not be limited to the description of the preferred embodiments contained herein.

According to the present invention, there is provided an improved smoking device filter for substantially removing toxic and mutagenic compounds from tobacco smoke and a smoking device comprising such a filter.

Claims (13)

(a) providing at least one copper containing porphyrin; (b) producing a mixture of sodium carbonate, sodium sulfate, chitin and copper containing porphyrin; (c) heating the mixture for a sufficient time at one or more temperatures sufficient to covalently bond copper containing porphyrin to chitin; And (d) shaping the covalently bonded copper containing porphyrin and chitin into the first tobacco smoke filter segment, wherein the first tobacco smoke filter segment is prepared. (a) providing a first tobacco smoke filter segment made according to claim 1; (b) attaching the first tobacco smoke filter segment to the body of divided tobacco; And (c) attaching a second tobacco smoke filter segment substantially free of copper containing porphyrin to the body of divided tobacco. The method of claim 1, further comprising washing the mixture after heating the mixture. 3. The method of claim 2, wherein the second tobacco smoke filter segment attached to the body of divided tobacco comprises cellulose acetate fibers treated with triacetin. The method according to claim 1, wherein the copper containing porphyrin provided is copper phthalocyanine. 5. The copper containing porphyrin as claimed in claim 1, wherein the provided copper containing porphyrin is C.I. A reactive blue 21 dye. 5. The method of claim 1, wherein the resulting mixture of chitin and copper containing porphyrin comprises copper containing porphyrin to chitin in a weight ratio of about 1.2: 10. 6. 5. The method of claim 1, further comprising adding one or more additional substances to the chitin. 6. The method of claim 8, wherein the one or more additional substances are selected from the group consisting of activated carbon and lignin. The method of claim 8, wherein the one or more additional materials are selected from the group consisting of antioxidants, dry water, wetting agents, microcapsules, radical scavengers, surfactants, and combinations thereof. (a) providing a first tobacco smoke filter segment made according to claim 1; And (b) attaching the first tobacco smoke filter segment to the body of divided tobacco. Smoking device manufactured according to the method of claim 11. (a) providing a smoking device made according to claim 11; (b) igniting the body of divided tobacco such that smoke passes through the body of divided tobacco and into the filter; And (c) filtering smoke by passing the smoke through a filter.