2. Description of Related Art Various cigarette filters for reducing tar and nicotine intake are conventionally known. More specifically, U. S. Patent No. 5,404,890 to Gentry et al. discloses a cigarette filter that has carbon containing paper or molecular sieves. The paper

circumscribes filter material such as cellulose acetate tow, and serves as a plug wrap for a filter material.

U. S. Patent No. 5,671,757 to Woodings discloses a cigarette filter in which the body of the filter comprises paper containing or consisting of lyocell fibers. The filter may be a mono, dual or triple filter with the dual and triple filters comprising an acetate tow filter toward the exterior of the cigarette and a lyocell paper filter toward the interior of the cigarette. These lyocell fibers give the filter greatly improved tar retention properties at a wide range of pressure drops.

U. S. Patent No. 5,409,021 to Savaev et al. discloses a cigarette filter that includes at least two parts that are located in the direction of the tobacco smoke flow and joined by a wrapping means. One part of the filter is made from cellulose or acetatecellulose filter, while the other part is positioned on the side of the tobacco and is filled with an adsorbing substance such as lignin.

Even with such conventional filters, there is a need for an improved cigarette filter for further reduction of harmful substances while maintaining a sufficient level of taste and draw resistance.

SUMMARY OF THE INVENTION The present invention provides an improved filter for a cigarette that reduces tar and nicotine intake significantly (by approximately 35-70%) by incorporating SAP particles while avoiding significant

changes in the original smoking characteristics, such as taste and draw resistance.

The surface activated particulate (SAP) particles according to the present invention, when made with a porous-fibrilled surface morphology and in the order of 0.2-100 microns in diameter, and preferably 0.5-50 microns in diameter, absorb significant amounts of tar and nicotine. These SAP particles are used in combination with connected cigarette filters such as cellulose acetate and polyolefin fiber filters. A similar type of SAP particles has previously been found to be particularly useful in making a liquid toner for electrophotographic imaging by the inventor of the present invention, as shown in U. S. Patent No.

5,358,822 which in incorporated herein by reference.

These SAP particles work especially well removing tar, nicotine, and other harmful substances from smoke because of their unique surface morphology and their surface chemistry. The surface morphology of these particles can be one of a smooth surface with small pores or a porous fibrilled surface that gives each particulate a large surface area. Such porous or porous fibrilled surface morphology provides significant physical adsorption and mechanical filtering effects to stop harmful substances from both the particulate phase and the gas phase of cigarette smoke going through the SAP particle layer in a cigarette filter.

In addition, the surface chemistry of each of the particles is particularly adapted to picking up tar,

nicotine and other harmful substances in smoke. For example, the particles could be made from linear branched polymers that have the following functional groups: amides, amines, acrylates, carboxylic acids, carboxyls, esters, ethers, acetates, hydroxyls, sulfonates, sulfones, sulfides, cellulose, nitros, nitrates, nitrile, diols, alcohols, ketones, and acetals. Some of these functional groups may form an acid (or electron acceptor)-base (or electron donor) interaction with the tar, nicotine, and other harmful substances in cigarette smoke. For example, a polymer with a carboxylic acid active group may interact with basic elements such as nicotine from a particulate phase of cigarette smoke and pyridine from a gas phase of cigarette smoke, and therefore, absorb and remove them from the smoke. In this way, these harmful substances will latch with the particles in the filter and thereby be filtered out of the smoke.

The present invention has been found to reduce tar and nicotine intake by 35-70%. In a first embodiment of the present invention, the SAP particles are in the form of a powder membrane of between 10 to 500 microns in thickness, and preferably 20 to 200 microns in thickness, disposed within a conventional filter. This membrane or screen is enclosed between a first and second segment in a filter.

In another embodiment of the present invention, the filter is a series of SAP particles that are dispersed throughout the filter. In both of these

embodiments, the SAP particles are contained within the filter.

In another embodiment of the present invention, a filter for a cigarette comprises a plurality of surface activated particulate particles positioned within the cigarette filter, wherein the surface activated particulate particles are for removing harmful substances from cigarette smoke.

In another embodiment of the present invention, a filter for a cigarette comprises a plurality of surface activated particulate particles positioned within the cigarette filter, wherein the surface activated particulate particles are for removing harmful substances from cigarette smoke, wherein each one of the plurality of surface activated particulate particles has a fibril surface morphology.

Alternatively, each one of the plurality of surface activated particulate particles may have a porous or porous-fibrilled surface morphology. Also, each one of the plurality of surface activated particulate particles may have a smooth surface. Also, each one of the plurality of surface activated particulate particles may have a variety of shapes, including preferably a spherical shape.

In another embodiment of the present invention, a filter for a cigarette comprises a plurality of surface activated particulate particles positioned within the cigarette filter, wherein the surface activated particulate particles are for removing harmful substances from cigarette smoke, wherein each one of

the plurality of surface activated particulate particles has a diameter that is less than 100 microns.

Also, each one of the plurality of surface activated particulate particles may have a diameter that is greater than 0.2 microns. Furthermore, each one of the plurality of surface activated particulate particles may have a diameter that is between 0.2 to 100 microns.

Moreover, each one of the plurality of surface activated particulate particles may have a diameter that is less than 50 microns, or a diameter that is greater than 0.5 microns, or a diameter that is between 0.5 to 50 microns.

In another embodiment of the present invention, a filter for a cigarette comprises a plurality of surface activated particulate particles positioned within the cigarette filter, wherein the surface activated particulate particles are for removing harmful substances from cigarette smoke, wherein the plurality of surface activated particulate particles may be made from an organic material, or an inorganic material, or a polymeric material, or a starch or cellulose derivative, or any combination thereof.

In another embodiment of the present invention, a filter for a cigarette comprises a plurality of surface activated particulate particles positioned within the cigarette filter, wherein the surface activated particulate particles are for removing harmful substances from cigarette smoke, wherein the plurality of surface activated particulate particles are made

dispersed throughout the filter, alternatively, are dispersed throughout a section of the filter.

In another embodiment of the present invention, a filter for a cigarette comprises a plurality of surface activated particulate particles positioned within the cigarette filter, wherein the surface activated particulate particles are for removing harmful substances from cigarette smoke, wherein the plurality of surface activated particulate particles form a powder membrane that is less than 500 microns thick.

The thickness may also be greater than or equal to 10 microns thick or between 10 to 500 microns thick.

Furthermore, the thickness may be at least 20 microns thick, or less than 200 microns thick, or between 20 to 200 microns thick.

In another embodiment of the present invention, a filter for a cigarette comprises a plurality of surface activated particulate particles positioned within the cigarette filter, wherein the surface activated particulate particles are for removing harmful substances from cigarette smoke, wherein the plurality of surface activated particulate particles are formed from a polymer solution. Also, the particles may be formed from a polyamide/formic acid solution.

In another embodiment of the present invention, a filter for a cigarette comprises a plurality of surface activated particulate particles positioned within the cigarette filter, wherein the surface activated particulate particles are for removing harmful substances from cigarette smoke, wherein the plurality

of surface activated particulate particles are formed from a polymer with one of the following functional groups including amide, amine, acrylate, carboxylic acid, carboxyl, ester, ether, acetate, hydroxyl, sulfonate, sulfone, sulfide, cellulose, nitro, nitrate, nitrile, diol, alcohol, ketone, and acetal with an average molecular weight of between 1000 to 100,000.

In another embodiment of the present invention, a filter for a cigarette comprises a plurality of surface activated particulate particles positioned within the cigarette filter, wherein the surface activated particulate particles are for removing harmful substances from cigarette smoke, wherein the plurality of surface activated particulate particles interact with a plurality of chemical components from the cigarette smoke by chemical adsorption so that the tar, nicotine, and other harmful substances from cigarette smoke are removed.

In another embodiment of the present invention, a filter for a cigarette comprises a plurality of surface activated particulate particles positioned within the cigarette filter, wherein the surface activated particulate particles are for removing harmful substances from cigarette smoke, wherein the plurality of surface activated particulate particles interact with a plurality of chemical components from the cigarette smoke by acid (electron acceptor)-base (electron donor) interaction so that the tar, nicotine, and other harmful substances from cigarette smoke are removed.

In another embodiment of the present invention, a filter for a cigarette comprises a plurality of surface activated particulate particles positioned within the cigarette filter, wherein the surface activated particulate particles are for removing harmful substances from cigarette smoke, wherein the plurality of surface activated particulate particles are for absorbing tar and nicotine from cigarette smoke.

In another embodiment of the present invention, a filter for a cigarette comprises a plurality of surface activated particulate particles positioned within the cigarette filter, wherein the surface activated particulate particles are for removing harmful substances from cigarette smoke, wherein the plurality of surface activated particulate particles are for absorbing harmful substances from a particulate phase of the cigarette smoke.

In another embodiment of the present invention, a filter for a cigarette comprises a plurality of surface activated particulate particles positioned within the cigarette filter, wherein the surface activated particulate particles are for removing harmful substances from cigarette smoke, wherein the plurality of surface activated particulate particles are for absorbing harmful substances from a gas phase of the cigarette smoke.

In another embodiment of the present invention, a filter for a cigarette comprises a plurality of surface activated particulate particles positioned within the cigarette filter, wherein the surface activated

particulate particles are for removing harmful substances from cigarette smoke, wherein the plurality of surface activated particulate particles with a porous or fibril or porous-fibril surface morphology interact with a plurality of chemical components from the cigarette smoke by physical adsorption so that the harmful substances in a gas phase are removed from the cigarette smoke.

In another embodiment of the present invention, a filter for a cigarette comprises a plurality of surface activated particulate particles positioned within the cigarette filter, wherein the surface activated particulate particles are for removing harmful substances from cigarette smoke, wherein the plurality of surface activated particulate particles with a porous or fibril or porous-fibril surface morphology provide a mechanical filtration effect to filter our the harmful substances from cigarette smoke.

In another embodiment of the present invention, a filter for a cigarette comprises a plurality of surface activated particulate particles positioned within the cigarette filter, wherein the surface activated particulate particles are for removing harmful substances from cigarette smoke, wherein the plurality of surface activated particulate particles interact with a plurality of chemical components of cigarette smoke by a combination of chemical adsorption, physical adsorption, and mechanical filtration effects so that tar, nicotine, and other harmful substances from cigarette smoke are removed.

In another embodiment of the present invention, a filter for a cigarette comprises a first filter end connected to the cigarette; a second filter end opposite the first filter; and a membrane placed between the first filter end and the second filter end; wherein the membrane comprises a plurality of surface activated particulate particles, wherein the plurality of surface activated particulate particles are stacked together, and wherein the membrane is at least 20 microns thick.

In another embodiment of the present invention, a filter for a cigarette comprises a first filter end connected to the cigarette; a second filter end opposite the first filter end; and a middle filter section positioned between the first filter end and the second filter end; wherein the middle filter section has a plurality of surface activated particulate particles dispersed throughout the middle filter section.

One object of the present invention is to provide a filter that reduces tar, nicotine and other harmful substances.

Another object of the present invention is to create a closed filter for housing SAP particles.

Another object of the present invention is to provide a filter that reduces tar and nicotine intake by 35-70%.

Another object of the present invention is to create a highly effective filter that does not

significantly change the original smoking characteristics such as taste and draw resistance.

BRIEF DESCRIPTION OF THE DRAWINGS Other objects, features, and benefits of the present invention will become apparent from the following detailed description of preferred embodiments thereof taken in conjunction with the accompanying figures, wherein similar reference characters denote similar elements throughout the several views: FIG. 1A shows a perspective view of a filter according to a first embodiment of the present invention wherein the filter is broken open to expose the powder membrane; FIG. 1B is a cross sectional view of a powder membrane housed within a filter according to the first embodiment of the present invention as shown in FIG.

1A; FIG. 2A is a perspective view of a filter according to a second embodiment of the present invention; FIG. 2B is a cross sectional view of the second embodiment shown in FIG 2A showing particles dispersed throughout the filter; FIG. 3A shows an electro-micrograph of a first embodiment of the particulate forming the present invention; FIG. 3B shows an electro-micrograph of a second embodiment of the particulate forming the present invention; and

FIG. 3C shows an electro-micrograph of a third embodiment of the particulate forming the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The surface activated particulate (SAP) particles can be created by one of four processes. These processes contain the following basic steps: 1) dissolve the polymer in a good solvent; 2) heat the solution; 3) titrate the solution with a non solvent; 4) heat the solution to form a clear appearance; 5) cool rapidly; 6) decant to top layer; 7) wash the polymer particles in a non solvent; and 8) collect the polymer and dry.

Each one of the four processes is explained by the example set forth below: Example 1 In step 1, twenty grams of a polyamide with an average molecular weight of between 1,000 to 100,000, and preferably between 5,000 and 20,000 were dissolved in 1,000 grams of a solvent such as formic acid at room temperature to form 2 wt% of clear solution. In step 2, the polyamide/formic acid clear solution is heated up to a higher temperature between room temperature and 100 °C and preferably between 30 °C and 60 °C. Next in step 3, the solution is titrated slowly with a non solvent such as water until the mixture reaches a cloudy appearance. In step 4, the mixture is heated up to a temperature where the solution is no longer cloudy

but instead has a clear appearance. Step 5 involves cooling the clear solution rapidly by immersing it in an ice bath for at least 30 minutes to precipitate the polyamide out of the solution. During the cooling process, the particles settle on the bottom of the jar.

In step 6, the precipitated polymer particles are collected and washed with water. The particles and water are shaken together and then the solution left to sit to separate the particles out from the mixture.

Finally, in step 7, the polymer particles are collected and dried to remove any excess solvent. These steps result in a fine powder of polymer particles with a narrow size distribution that is formed after drying.

The above dry powder is incorporated into a cigarette filter. When these particles are introduced into the cigarette filter, the original cigarette's tar and nicotine deliveries are significantly reduced by an amount of between 35% to 70%. The effectiveness of these reductions is based upon the functional groups of the polymer, particle size, surface morphology, and the means for incorporating the SAP particles into cigarette filter.

Example II In step 1, a polyamide with an average molecular weight of between 1,000 to 100,000 and preferably between 5,000 and 20,000 is dissolved in a solvent such as formic acid, acetic acid, and chloro-acetic acid at room temperature to form a polymer solution from 0.5 wt% to 10 wt% and preferably from 1 wt% to 5 wt%. In

step 2, the polyamide clear solution is heated up to a higher temperature between room temperature to 100 OC and preferably between 30 OC and 80 °C. Next in step 3, the solution is titrated slowly with a non solvent such as hydrocarbons, aliphatic alcohols, chloroform, ethers, esters, aliphatic ketones until the mixture reaches a cloudy appearance. In step 4, the mixture is heated up to a temperature where the solution is no longer cloudy but instead has a clear appearance. Step 5 involves cooling the clear solution rapidly by immersing it in an ice bath for at least from 10 to 60 minutes and preferably from 20 to 40 minutes to precipitate the polyamide out of the solution. During the cooling process, the particles settle on the bottom of the jar. In step 6, the solution is decanted so that the top layer of solution is removed. Next, in step 7, the precipitated polymer particles are collected and washed with a non solvent. The particles and non solvent are shaken together and then the solution is left to sit to separate the particles out from the mixture. Finally, in step 8, the polymer particles are collected and dried to remove any excess solvent. The results of these steps are that a fine powder of polymer particles with a narrow size distribution is formed after drying.

Example III In step 1, linear polymers with functional groups such as amides, amines, acrylates, carboxylic acids, carboxyls, esters, ethers, acetates, hydroxyl,

sulfonates, sulfones, sulfides, cellulose, nitros, nitrates, nitrile, diols, alcohols, ketones, and acetals with an average molecular weight of between 1,000 to 100,000, and preferably between 5,000 and 20,000 is dissolved in a solvent to form a polymer solution from 0.5 wt% to 10 wt% and preferably from 1 wt% to 5 wt%. In step 2, the polymer solution is heated up to a higher temperature between room temperature and the boiling point of the solvent.

Next, in step 3, the solution is titrated slowly with a poor solvent or a non solvent for the polymers until the mixture reaches a cloudy appearance In step 4, the mixture is heated up to a temperature where the solution is no longer cloudy but instead has a clear appearance. Step 5 involves cooling the clear solution rapidly by immersing it in a cold environment such as an ice bath for at least from 5 to 120 minutes and preferably from 20 to 60 minutes to precipitate the polymer out of the solution. During the cooling process, the particles settle on the bottom of the jar.

In step 6, the solution is decanted so that the top layer of solution is removed. Next, in step 7, the precipitated polymer particles are collected and washed with a poor or non solvent. The particles and non solvent are shaken together and then the solution is left to sit to separate the particles out from the mixture. Finally, in step 8, the polymer particles are collected and dried to remove any excess solvent. The results of these steps are that a fine powder of

polymer particles with a narrow size distribution is formed after drying.

Example IV In step 1, linear polymers with functional groups such as amides, amines, acrylates, carboxylic acids carboxyls, esters, ethers, acetates, hydroxyls, sulfonates, sulfones, sulfides, cellulose, nitros, nitrates, nitrile, diols, alcohols, ketones, and acetals with an average molecular weight of between 1,000 to 100,000 and preferably between 5,000 and 20,000 is dissolved in a theta solvent of the selected polymer to form a polymer solution from 0.5 wt% to 10 wt% and preferably from 1 wt% to 5 wt%. In step 2, the polymer solution is heated up to a higher temperature above the theta temperature of the solvent. Step 3 involves cooling the clear solution below the theta temperature rapidly for at least from 5 to 120 minutes and preferably from 20 to 60 minutes to precipitate the polymer out of the solution. During the cooling process, the particles settle on the bottom of the jar.

In step 4, the solution is decanted so that the top layer of solution is removed. Next in step 5, the precipitate polymer particles are collected and washed with a poor solvent or a non solvent. The particles and non solvent are shaken together and the solution is left to sit to separate the particles out from the mixtures. Finally, in step 6, the polymer particles are collected and dried to remove any excess solvent.

The results of these steps are that a fine powder of

polymer particles is formed with a narrow size distribution after drying.

Once the polymer is formed, it is applied to a conventional cigarette filter with or without air ventilation construction. The original cigarette tar and nicotine deliveries were significantly reduced by 35-70% from the SAP particles incorporated in the cigarette filter. These rates for reducing tar and nicotine depend upon the molecular structure and functional groups of the polymer, particle size, surface morphologies, and the means for incorporating the SAP particles in the cigarette filter as well as the construction of the cigarette filter.

The above dry polymer powders as described in the above examples were applied to commercial cigarette filters. In this case, the tar and nicotine deliveries were significantly reduced with the SAP particles incorporated in the cigarettes by about 35-70%.

Referring to FIG. 1A, there is shown a perspective view of a first embodiment of cigarette filter 15 attached to cigarette 10. Filter 15 contains a series of surface activated particulate (SAP) particles 20 that is positioned between first filter end 30a and second filter end 30b. FIG. 1B shows that particles 20 can be placed in the filter as a powder membrane in the range of 10 to 500 microns thick, or preferably in the range of 20 to 200 microns thick. Particles 20 are designed to catch nicotine and tar, and other harmful chemicals as they pass through the cigarette and into a smoker's lungs.

FIG. 2A shows a second embodiment of the SAP particle filter shown as filter 25. Filter 25 comprises a first filter end 30a connected to cigarette 10, and extended middle filter 35, and an end filter 30b enclosing middle filter 35. Middle filter 35 contains a plurality of SAP particles 20 dispersed throughout the length of the filter. This filter acts as a screen to cut down on the tar and nicotine generated by cigarette 10. In this design, tar, nicotine and other harmful chemicals are filtered out of the smoke throughout the length of the filter into particles 20.

FIG. 2B shows a cross sectional view of filter 25 showing particles 20 as they fit between ends 30a and 30b. This view shows that particles 20 fit inside cigarette filter 25.

FIG. 3A shows a first embodiment of particles 20 wherein individual balls 50 are about identical in diameter. Balls 50 have a fine porous smooth surface and are formed by using acetone as a non solvent solution to precipitate the particles out.

FIG. 3B shows a second embodiment of particles 20 wherein individual balls 60 are shown. Balls 60 have a rough surface and are formed by using methanol as a non solvent solution to precipitate the particles out.

FIG. 3C shows a third embodiment of particles 20 wherein individual balls 70 are shown. Balls 70 have a roughened surface and are formed by using water as a non solvent solution to precipitate the particles out of the solution.

The surface activated particulate (SAP) particles according to the present invention, when made with a porous-fibrilled surface morphology and in the order of 0.2-100 microns in diameter, and preferably 0.5-50 microns in diameter, absorb significant amounts of tar and nicotine. As explained above, these SAP particles are used in combination with connected cigarette filters such as cellulose acetate and polyolefin fiber filters.

The differences between the surface morphologies of these particles are due to the solvency of the three different non solvents, the interfacial tension between the polymer and the non solvent, and the evaporation rate of the non solvents. In particular, the porous fibrilled particles have a relatively large surface area which is suited for interacting with tar, nicotine or other harmful chemicals in cigarette smoke. Such porous or porous fibrilled surface morphology provides significant physical adsorption and mechanical filtering effects to filter out harmful substances such as tar and nicotine in cigarette smoke.

In addition, the surface chemistry of these particles is particularly suited for picking up harmful chemicals in cigarette smoke. For example, these particles are formed with active groups such as amide or carboxylic acids, so they are particularly suited for acid (or electron acceptor)-base (or electron donor) interactions with tar, nicotine or other harmful chemicals in smoke.

The following table 1 shows the results of using particles 20 within filters 15 and 25. This table lists the effect of the SAP particles in cigarette filters in regards to the reduction of tar and nicotine deliveries of cigarettes. A series of ten cigarettes were tested for tar content and nicotine content both with and without the use of the filter. The test results were found using a Filtrona SM350 smoking machine and GC Varian Star 3600.

Although the example of cigarettes has been used, this invention may be applied to cigars, pipes, and other tobacco products or other products that create harmful substances such as tar and nicotine for which this invention may offer benefits.

While the present invention has been shown and described with reference to preferred embodiments presently contemplated as best modes for carrying out the invention, it is understood that various changes may be made in adapting the invention to different embodiments without departing from the broader inventive concepts disclosed herein and comprehended by the claims which follow.

TABLE 1: THE EFFECT OF THE SAP PARTICLES INCORPORATING IN CIGARETTE FILTER ON REDUCTION OF TAR AND NICOTINE DELIVERIES 0<BR> CIGARETTES. Test Cigarette Brand Tar Contenl Nicotine Content Amount of SAP Tar Content ARer Nicotine Content # Before Adding Before Adding Particles Added Adding SAP Afler Adding SAP Particles SAP Particles Into Filter Particle SAP Particles (mg) (mg) (mg) (mg) (mg) 1 555, Regular 13.8 1.12 6 7.3 (53%) 0.52 (46%) 2 555, Regular81.129.16.613. (48%) 0.47 (42%) (UK) 3 Marlboro, Regular 13.6 0.83 9.3 7.7 (56%) 0.50 (60%) (US) 4 Marlboro, Regular 13.6 0.83 9.9 (52%) 0.48(58%) - (US) 5 DunHill, International 13.9 1.36 10.1 6.2(44%) 0.67 (49%) Regular (UK) 6 DunHill, International 1.36 8.9 7.1 (51%) 80 (59%) Regular(UK) 7 Lark, Regular 17.1 1.75 7.2 11.2(66%) 1.1 (62%) (US) 8 Lark, Regular 17.1 1.75 10.6 (52%) 0.88 (50%) JTJS 9 LongLife, Regular 18.6 1.35 6.3 12.0 (64%) 0.83 (61%) (Taiwan) 10 LongLife, Regular18.61.35 8.1 9.6 (51%) 0.66 (49%) (Taiwan) The procedures of the above tests are based up ISO 3308, ISO 4387, ISO 10315 & ISO 10362-1 standards.<BR> <P>The above test results are done by using Filtrona SM350 Smoking Machine and GC Varian Star 3600.