EP0552234A1

EP0552234A1 - A combination for improved delivery of tobacco modifying agents.

Info

Publication number: EP0552234A1
Application number: EP91918236A
Authority: EP
Inventors: Dale Edwin Mathis; James Edward Harris
Original assignee: Eastman Kodak Co
Current assignee: Eastman Chemical Co
Priority date: 1990-10-04
Filing date: 1991-09-30
Publication date: 1993-07-28
Anticipated expiration: 2011-09-30
Also published as: WO1992005713A1; CA2092176A1; DK0552234T3; DE69121577T2; ATE141468T1; DE69121577D1; JPH06502068A; ES2093109T3; EP0552234B1; CA2092176C; GR3021634T3

Abstract

Disclosed are articles, such as smoke filters, which contain fibers that have complex geometry in combination with tobacco modifying agents such as flavorants. The fibers are preferably made of polyester such as poly(ethylene terephthalate) and preferably are capable of spontaneously transporting water or n-decane on their surfaces. The articles of the invention result in improved delivery of the tobacco modifying agent to the user.

Description

A COMBINATION FOR IMPROVED DELIVERY OF

TOBACCO MODIFYING AGENTS

Field of the Invention

This invention concerns certain fibers in

combination with tobacco modifying and/or selective removal agents.

Background of the Invention

Many types of tobacco modifying agents are known in the art to be added to smoking products to modify the tobacco smoke. For example, flavorants are added to smoking products to enhance their taste and to

compensate for variations in tobacco quality and blend. Although flavorants are traditionally applied to the tobacco portion of the smoking product, this practice results in only a small fraction of the flavorant ever reaching the smoker. Most of a flavorant added to the tobacco is lost in the sidestream smoke produced during the static burn period of the smoking article or is removed by the smoke filter. The low flavorant delivery efficiencies associated with application on tobacco necessitates the use of relatively large quantities of flavorant to achieve the desired effect. Because many of these flavorants, such as menthol, for example, are expensive, inefficient utilization can add significantly to the cost of the smoking product. In addition, flavorants applied to the tobacco are subjected to the high heat of combustion which can undesirably alter their organoleptic characteristics.

In response to these problems, there has been substantial effort to apply flavorants to the filter. It was shown many years ago that smoke aerosols could transport significant quantities of relatively non- volatile materials from a structure of moderate surface area, even though a gas at a comparable temperature is ineffective in this regard. Attempts at the practical implementation of this phenomenon using cellulose acetate filters revealed, however, that although

aerosols transported flavorant very efficiently from freshly made filters, this advantage was lost as the flavorant diffused away from the surface and into the bulk of the filter fibers.

Efforts to solve this problem by using polymers impermeable to the flavorants, such as polypropylene, eliminated the time dependence of flavorant delivery observed with cellulose acetate filters, but did not permit the development of a functional flavorant

delivery system. The causes of this failure were, first, the flavorant delivery efficiencies for these nonpermeable polymer systems were too low to be useful, and second, impermeable filter media had no affinity for the flavorant which consequently diffused to the tobacco where it endured the same fate as flavorants applied directly to the tobacco.

In spite of years of concerted effort, neither the cigarette nor the filter material industry has developed an efficient general flavorant delivery system that does not absorb or loose the flavorant over time.

Prior art of this area reflects a strong interest in technology for the efficient and consistent delivery of tobacco modifying agents, especially flavorants.

However, the abundant patented technologies for

flavorant delivery almost invariably employ one of the following four strategies:

1. A flavorant is contained by some physical means and is released either by mechanical destruction of the containment apparatus or by controlled leakage (see, for example, U.S. Patents 3,219,041;

3,297,038; 3,339,557; and 4,720,423). 2. A flavorant is adsorbed on a material whose surface has been customized so that the flavorant will be displaced by the moisture or heat in the smoke (see, for example, U.S. Patents 3,236,244;

3,280,823; and 4,662,384).

3. A flavorant is absorbed in a polymeric matrix and is then released by the plasticizing action of moisture or heat in the smoke (see, for example, U.S. Patents 4,662,384; 3,144,024; and 4,729,391). A portion of the prior art in this area addresses the concept of modifying the fiber shape or filter geometry of current cellulose acetate filters to achieve improved flavorant containment or delivery (see, for example, U.S. Patents 4,180,536,

4,619,279; and 4,821,750).

4. A flavorant undergoes a chemical reaction with

another compound to form a new compound that will regenerate the original flavorant upon thermal decomposition (see U.S. Patent 3,288,146).

Although there is substantial prior art, virtually every implementation of this art possesses limitations which render its commercial application impractical.

These limitations are largely defined by the flavorant delivery strategy employed and will, therefore, be so organized here.

Mechanical or physical flavorant containment devices which are incorporated into the filter and ruptured prior to smoking are very complex and expensive to produce. They introduce significant variation into the performance of the smoking article because of inconsistencies in the pattern of their breakage, and they interfere with the normal function of the filter by altering smoke flow through the filter. They also increase the effort and complexity to the consumer who uses the product. Adsorbed flavorants which are incorporated into the filter and released by the heat or moisture content of the smoke are not efficiently delivered until enough of the smoking article has been consumed to allow adequate moisture and heat to reach the filter. As a

consequence, the flavorant is not available to augment smoke taste during the first few puffs, when it is generally acknowledged as being most needed. In

addition, absorbants must be customized to achieve the desired release characteristics for each flavorant and, therefore, are not useful for delivering naturally occurring flavoring materials which consist of large numbers of independent chemical entities.

Absorbed flavorants which are dissolved in polymer matrices and released by the plasticizing action of moisture or heat in the smoke are subject to the same limitations as adsorbed flavorants. In addition, absorbed flavorants are subject to time dependent losses in delivery efficiency because of diffusion of the flavorant into the bulk of the fiber polymer. This limitation is especially evident when a conventional cellulose acetate filter is used as the flavorant absorber.

Derivatized flavorants are almost always

inappropriate for use in filter flavorant delivery systems because relatively high temperatures are

required for their release. Derivatized flavorants are, therefore, typically applied to the tobacco portion of the smoking product, where the liberated flavorant produced during combustion is subject to chemical alteration and loss during the static burn period of the smoking article. The development of derivatized

flavorants is highly specific for each flavorant and, therefore, excludes naturally occurring flavoring materials which are composed of a large number of independent chemical entities.

Although flavorants are the most commonly used tobacco modifying agents, selective removal additives can also serve as tobacco modifying agents. In contrast to flavorants , selective removal additives modify tobacco smoke by removing, rather than adding, certain compounds or classes of compounds. Selective removal additives are applied to the filter and, therefore, like flavorants, can be absorbed by the filter fibers and lose their effectiveness. Here, too, significant improvements in the performance of selective removal additives could be achieved by overcoming the

limitations imposed by the substrate to which the additives are applied.

Such fibers capable of transporting hydrophilic or hydrophobic fluids will be referred to herein as

"spontaneously transportable fibers" or, alternatively, "spontaneously wettable fibers". We have unexpectedly discovered that use of fibers of sufficiently complex geometry, especially spontaneously transportable fibers, in combination with tobacco modifying agents, such as flavorants, results in improved delivery of such agents. We have also unexpectedly discovered that use of these fibers in combination with selective removal additives results in improved selective removal of unwanted materials such as phenol.

Summary of the Invention

The present invention is directed to a combination comprising at least one fiber of sufficient geometry and at least one tobacco modifying agent.

The fiber useful in the present invention has at least one continuous groove oriented axially along the fiber wherein said fiber has a cross-section having a shape factor X that satisfies the following equation:

wherein

P is the perimeter of the fiber and r is the radius of the circumscribed circle circumscribing the fiber cross-section and D is the minor axis dimension across the fiber cross-section.

In a preferred embodiment, the fiber useful in the present invention is capable of spontaneously

transporting water on the surface thereof and has at least one continuous groove oriented axially along the fiber, and said fiber satisfies the following equation

(1-X cos θ_a) < 0,

wherein

θ _a is the advancing contact angle of water measured on a flat film made from the same material as the fiber and having the same surface treatment, if any,

X is a shape factor of the fiber cross-section that satisfies the following equation

wherein

P_w is the wetted perimeter of the fiber and r is the radius of the circumscribed circle

circumscribing the fiber cross-section and D is the minor axis dimension across the fiber

cross-section.

In another preferred embodiment, the fiber useful in the present invention is capable of spontaneously transporting n-decane on the surface thereof and has at least one continuous groove oriented axially along the fiber, and said fiber satisfies the following equation (1-X cos θ_a) < 0,

wherein

θ_a is the advancing contact angle of n-decane measured on a flat film made from the same material as the fiber and having the same surface treatment, if any,

wherein

cross-section.

For all of the fibers useful in the present

invention, it is preferred that X is greater than 1.2, more preferably greater than about 2.5, most preferably greater than about 4. Also, it is preferred that is greater than 1, more preferred is where is between

1.5 and 5.

For the fibers that spontaneously transport water, it is preferred that the fiber of the invention

satisfies the formula: γ_LA · · (1-X cos θ_a) ≤ -0.3,

wherein γ_LA is the surface tension of water in air in dynes/cm, ρ is the fiber density in grams/cc, and dpf is the denier (kg/m ) of the single fiber. The combination of the invention preferably

comprises a plurality of the fibers of the invention and at least one tobacco modifying agent wherein the combination is in the form of a tobacco smoke filter in substantially cylindrical form.

Brief Description of the Drawings

Figure 1 - graph of percent delivery efficiency versus milligrams (mg) of triacetin per filter for a cigarette filter of the invention and for a conventional cigarette filter. The o symbols represent filters of the invention and the ● symbols represent filters made from fibers of round cross-section.

Figure 2A - illustration of the behavior of a drop of a fluid which has just contacted a fiber that is spontaneously transportable at time = 0. The arrows labelled "LFA" indicate the location of the

liquid-fiber-air interface.

Figure 2B - illustration of the behavior of a drop of a fluid on a fiber that is spontaneously

transportable at time = t₁ (t₁ >0). The arrows labelled "LFA" indicate the location of the liquid-fiber-air interface.

Figure 2C - illustration of the behavior of a drop of a fluid on a fiber that is spontaneously

transportable at time = t₂ (t₂ >t₁). The arrows labelled "LFA" indicate the location of the

liquid-fiber-air interface.

Figure 3 - schematic representation of an orifice of a spinneret useful for producing a spontaneously transportable fiber.

Figure 4 - schematic representation of an orifice of a spinneret useful for producing a spontaneously transportable fiber.

Figure 5 - schematic representation of an orifice of a spinneret useful for producing a spontaneously transportable fiber. Figure 6 - schematic representation of an orifice of a spinneret useful for producing a spontaneously transportable fiber.

Figure 6B - schematic representation of an orifice of a spinneret useful for producing a spontaneously transportable fiber.

Figure 7 - schematic representation of an orifice of a spinneret having 2 repeating units, joined end to end, of the orifice as shown in Figure 3.

Figure 8 - schematic representation of an orifice of a spinneret having 4 repeating units, joined end to end, of the orifice as shown in Figure 3.

Figure 9 - photomicrograph of a poly(ethylene terephthalate) fiber cross-section made using a

spinneret having an orifice as illustrated in Figure 3 (specific dimensions of spinneret orifice described in Example 1).

Figure 10 - photomicrograph of a polypropylene fiber cross-section made using a spinneret having an orifice as illustrated in Figure 3 (specific dimensions of spinneret orifice described in Example 2).

Figure 11 - photomicrograph of a nylon 66 fiber cross-section made using a spinneret having an orifice as illustrated in Figure 3 (specific dimensions of spinneret orifice described in Example 2).

Figure 12 - schematic representation of a

poly (ethylene terephthalate) fiber cross-section made using a spinneret having an orifice as illustrated in Figure 4 (specific dimensions of spinneret orifice described in Example 8).

Figure 13 - photomicrograph of a poly(ethylene terephthalate) fiber cross-section made using a

spinneret having an orifice as illustrated in Figure 5 (specific dimensions of spinneret orifice described in Example 9). Figure 14 - photomicrograph of a poly(ethylene terephthalate) fiber cross-section made using a

spinneret having an orifice as illustrated in Figure 7 (specific dimensions of spinneret orifice described in Example 10).

Figure 15 - photomicrograph of a poly(ethylene terephthalate) fiber cross-section made using a

spinneret having an orifice as illustrated in Figure 8 (specific dimensions of spinneret orifice described in Example 11).

Figure 16 - schematic representation of a fiber cross-section made using a spinneret having an orifice as illustrated in Figure 3 (Example 1) . Exemplified is a typical means of determining the shape factor X.

Figure 17 - photomicrograph of a poly(ethylene terephthalate) fiber cross-section made using a

spinneret having an orifice as illustrated in Figure 6 (specific dimensions of spinneret orifice described in Example 12).

Figure 17B - schematic representation of a

poly(ethylene terephthalate) fiber cross-section made using a spinneret having an orifice as illustrated in Figure 6B (specific dimensions of spinneret orifice described in Example 13).

Figures 18 and 19 - graphs showing the performance of the invention for maintaining a constant delivery efficiency for glycerol triacetate over extended periods of storage. Detailed Description of the Invention

The fibers useful in the present invention have a complex cross-section geometry that results in a surface area that allows for more efficient delivery of tobacco modifying agent to the user. These fibers also allow for more efficient selective removal when selective removal additives are applied to the fibers of the present invention. The fibers are preferably

spontaneously transportable. For hydrophilic tobacco modifying agents, the fibers are preferably the

preferred fibers that are capable of spontaneously transporting water on the surfaces thereof. Similarly, for hydrophobic tobacco modifying agents, the fibers are preferably the preferred fibers that are capable of spontaneously transporting n-decane on the surfaces thereof.

It is not desired to be bound by any particular theory or mechanism; however, it is believed that a spontaneously wettable fiber, when contacted with an appropriate fluid tobacco modifying agent, transports said agent on the fiber surface thereby substantially or completely coating the fiber with the agent. Also, it is believed that if a spontaneously wettable fiber is dipped or immersed in an appropriate fluid tobacco modifying agent and then removed from the fluid, said fiber retains a sufficient amount of said fluid which also results in a fiber substantially or completely coated with said agent. As used in this context, "an appropriate fluid tobacco modifying agent" is one which is capable of being spontaneously transported by the fiber in question. The coated fibers are optionally allowed to dry or substantially dry prior to use.

The three important variables fundamental to the liquid transport behavior are (a) surface tension of the liquid, (b) wettability or the contact angle of the solid with the liquid, and (c) the geometry of the solid surface. Typically, the wettability of a solid surface by a liquid can be characterized by the contact angle that the liquid surface (gas-liquid interface) makes with the solid surface (gas-solid surface). Typically, a drop of liquid placed on a solid surface makes a contact angle, θ , with the solid surface. If this contact angle is less than 90°, then the solid is considered to be wet by the liquid. However, if the contact angle is greater than 90°, such as with water on Teflon (trademark) surface, the solid is not wet by the liquid. Thus, it is desired to have a minimum contact angle for enhanced wetting, but definitely, it must be less than 90°. However, the contact angle also depends on surface inhomogeneities (chemical and physical, such as roughness), contamination, chemical/physical

treatment of the solid surface, as well as the nature of the liquid surface and its contamination. Surface free energy of the solid also influences the wetting

behavior. The lower the surface energy of the solid, the more difficult it is to wet the solid by liquids having high surface tension. Thus, for example. Teflon, which has low surface energy does not wet with water. (Contact angle for Teflon-water system is 112°.)

However, it is possible to treat the surface of Teflon with a monomolecular film of protein, which

significantly enhances the wetting behavior. Thus, it is possible to modify the surface energy of fiber surfaces by appropriate lubricants/finishes to enhance liquid transport. The contact angle of polyethylene terephthalate (PET), nylon 66, and polypropylene with water is 80°, 71°, and 108°, respectively. Thus, nylon 66 is more wettable with water than PET. However, for polypropylene, the contact angle is >90°, and thus is nonwettable with water.

The second property of fundamental importance to the phenomena of liquid transport is surface tension of the liquid.

The third property of fundamental importance to the phenomena of liquid transport is the geometry of the solid surface. Although it is known that grooves enhance fluid transport in general, it has been

discovered that particular geometries and arrangements of deep and narrow grooves on fibers and treatments thereof can allow for the spontaneous surface transport of fluids in single fibers. Thus, preferred fibers for use herein are those with a combination of properties wherein an individual fiber is capable of spontaneously transporting water or n-decane on its surface.

The particular geometry of the deep and narrow grooves can be important. For example, in grooves which have the feature that the width of the groove at any depth is equal to or less than the width of the groove at the mouth of the groove, "bridging" of the liquid across the restriction is possible and thereby the effective wetted perimeter (Pw) is reduced. Of course, the fluid used to wet the fiber to determine the wetted perimeter is, accordingly, water in the case of fibers which spontaneously transport water, and n-decane in the case of fibers which spontaneously transport n-decane. In any case, it is preferred that Pw is substantially equal to the geometric perimeter.

The number of continuous grooves present in the fiber useful in the present invention is not critical as long as the required geometry is present. Typically there are at least 2 grooves present, and preferably less than 10.

"Spontaneously transportable" and derivative terms thereof refer to the behavior of a fluid in general and in particular a drop of fluid, such as water or

n-decane, when it is brought into contact with a single fiber such that the drop spreads along the fiber. Such behavior is contrasted with the normal behavior of the drop which forms a static ellipsoidal shape with a unique contact angle at the intersection of the liquid and the solid fiber. It is obvious that the formation of the ellipsoidal drop takes a very short time but remains stationary thereafter. Figures 2A, 2B and 2C illustrate spontaneous fluid transport on a fiber surface. The key factor is the movement of the location of the air, liquid, solid interface with time. If such interface moves just after contact of the liquid with the fiber, then the fiber is spontaneously

transportable; if such interface is stationary, the fiber is not spontaneously transportable. The

spontaneously transportable phenomenon is easily visible to the naked eye for large filaments (>20 denier (kg/m) per filament (dpf)) but a microscope may be necessary to view the fibers if they are less than 20 dpf. Colored fluids are more easily seen but the spontaneously transportable phenomenon is not dependent on the color. It is possible to have sections of the circumference of the fiber on which the fluid moves faster than other sections. In such case the air, liquid, solid interface actually extends over a length of the fiber. Thus, such fibers are also spontaneously transportable in that the air, liquid, solid interface is moving as opposed to stationary.

Spontaneous transportability is basically a surface phenomenon; that is the movement of the fluid occurs on the surface of the fiber. However, it is possible and may in some cases be desirable to have the spontaneously transportable phenomenon occur in conjunction with absorption of the fluid into the fiber. The behavior visible to the naked eye will depend on the relative rate of absorption vs. spontaneous transportability.

For example, if the relative rate of absorption is large such that most of the fluid is absorbed into the fiber, the liquid drop will disappear with very little movement of the air, liquid, solid interface along the fiber surface whereas if the rate of absorption is small compared to the rate of spontaneous transportability the observed behavior will be that of wicking or transport, as exemplified in Figures 2A through 2C. In Figure 2A, a drop of aqueous fluid is just placed on the fiber (time = 0). In Figure 2B, a time interval has elapsed (time = t₁) and the fluid starts to be spontaneously transported. In Figure 2C, a second time interval has passed (time = t₂) and the fluid has been spontaneously transported along the fiber surface further than at time = t₁.

A preferred fiber useful in the present invention is capable of spontaneously transporting water on the surface thereof. Distilled water can be employed to test the spontaneous transportability phenomenon;

however, it is often desirable to incorporate a minor amount of a colorant into the water to better visualize the spontaneous transport of the water, so long as the water with colorant behaves substantially the same as pure water under test conditions. We have found aqueous Syltint Poly Red (trademark) from Milliken Chemicals to be a useful solution to test the spontaneous

transportability phenomenon. The Syltint Poly Red solution can be used undiluted or diluted significantly, e.g., up to about 50x with water. In addition to being capable of transporting water, such a fiber useful in the present invention is also capable of spontaneously transporting a multitude of other hydrophilic fluids such as aqueous fluids. Aqueous fluids are those fluids comprising about 50% or more water by weight, preferred is about 75% or more water by weight, most preferred is about 90% or more water by weight. In addition to being able to transport aqueous fluids, such a fiber useful in the present invention is also capable of transporting an alcoholic fluid on its surface. Alcoholic fluids are those fluids comprising greater than about 50% by weight of an alcoholic compound of the formula

R-OH

wherein R is an aliphatic or aromatic group containing up to 12 carbon atoms. It is preferred that R is an alkyl group of 1 to 6 carbon atoms, more preferred is 1 to 4 carbon atoms. Examples of alcohols include

methanol, ethanol, n-propanol and iso-propanol.

Preferred alcoholic fluids comprise about 70% or more by weight of a suitable alcohol. Of course, it is also preferred that such a fiber is capable of spontaneously transporting hydrophilic tobacco modifying agents.

Another class of preferred fibers useful in the present invention is capable of spontaneously

transporting n-decane on the surface thereof. As in the case of water as described hereinbefore, the n-decane can be colorized for better visualization. In addition to being capable of spontaneously transporting n-decane, such a fiber is also typically capable of spontaneously transporting other hydrophobic fluids such as cycle- hexane, xylene or α-pinene. Of course, it is also preferred that such a fiber is capable of spontaneously transporting hydrophobic tobacco modifying agents.

The fibers useful in the invention can be comprised of any material known in the art capable of having a cross-section of the desired geometry. Preferred materials for use in the present invention are

polyesters.

The preferred polyester materials useful in the present invention are polyesters or copolyesterε that are well known in the art and can be prepared using standard techniques, such as, by polymerizing

dicarboxylic acids or esters thereof and glycols. The dicarboxylic acid compounds used in the production of polyesters and copolyesters are well known to those skilled in the art and illustratively include

terephthalic acid, isophthalic acid, p,p'-diphenyl- dicarboxylic acid, p,p'-dicarboxydiphenyl ethane, p,p'-dicarboxydiphenyl hexane, p,p'-dicarboxydiphenyl ether, p,p'-dicarboxyphenoxy ethane, and the like, and the dialkylesters thereof that contain from 1 to about 5 carbon atoms in the alkyl groups thereof.

Suitable aliphatic glycols for the production of polyesters and copolyesters are the acyclic and

alicyclic aliphatic glycols having from 2 to 10 carbon atoms, especially those represented by the general formula HO(CH₂)_pOH, wherein p is an integer having a value of from 2 to about 10, such as ethylene glycol, trimethylene glycol, tetramethylene glycol, and

pentamethylene glycol, decamethylene glycol, and the like.

Other known suitable aliphatic glycols include 1,4-cyclohexanedimethanol, 3-ethyl-1,5-pentanediol, 1,4-xylylene, glycol, 2,2,4,4-tetramethyl-1,3-cyclo- butanediol, and the like. One can also have present a hydroxylcarboxyl compound such as 4,-hydroxybenzoic acid, 4-hydroxyethoxybenzoic acid, or any of the other hydroxylcarboxyl compounds known as useful to those skilled in the art.

It is also known that mixtures of the above

dicarboxylic acid compounds or mixtures of the aliphatic glycols can be used and that a minor amount of the dicarboxylic acid component, generally up to about

10 mole percent, can be replaced by other acids or modifiers such as adipic acid, sebacic acid, or the esters thereof, or with modifiers that impart improved dyeability to the polymers.

The most preferred polyester for use in preparing the fiber useful in the invention is poly (ethylene terephthalate) (PET). Other materials that can be used to make the base fibers include polyamides such as a nylon, e.g.,

nylon 66 or nylon 6; polypropylene; polyethylene; and cellulose esters such as cellulose triacetate or

cellulose diacetate.

A single fiber useful in the present invention preferably has a denier (kg/m) of between about 1 and about 1,000, more preferred is between about 5 and about 70.

The fibers useful in the invention preferably have a surface treatment applied thereto. Such surface treatment may or may not be critical to obtain the desired spontaneous transportability property. The nature and criticality of such surface treatment for any given fiber can be determined by a skilled artisan through routine experimentation using techniques known in the art and/or disclosed herein. A preferred surface treatment, when a hydrophilic tobacco modifying agent is contemplated, is a coating of a hydrophilic lubricant on the surface of the fiber. A preferred surface

treatment, when a hydrophobic tobacco modifying agent is contemplated, is a coating of a hydrophobic lubricant on the surface of the fiber. Such coatings are typically uniformly applied at about a level of at least 0.05 weight percent, with about 0.1 to about 2 weight percent being preferred, based on the weight of the fiber.

Preferred hydrophilic lubricants include a potassium lauryl phosphate based lubricant comprising about 70 weight percent poly(ethylene glycol) 600 monolaurate. A preferred hydrophobic lubricant is mineral oil. Another surface treatment is to subject the fibers to oxygen plasma treatment, as taught in, for example, Plastics Finishing and Decoration. Chapter 4, Ed. Don Satas, Van Nostrand Reinhold Company (1986). Figures 3 through 8 illustrate spinneret orifices which will prepare fibers of a geometry suitable for use in the present invention.

In Figure 3, W is between 0.064 millimeters (mm) and 0.12 mm. X ₂ is 4W X

₄ is 2W ± 0.5W; X₆ is 6W X

₈ is 6W X

₁₀ is 7W X

₁₂ is 9W

X₁₄ is 10W X₁₆ is 11W X₁₈ is 6W W θ₂ is

30° ± 30°; θ₄ is 45° ± 45°; θ₆ is 30° ± 30°; and θ₈ is

45° ± 45°.

In Figure 4, W is between 0.064 mm and 0.12 mm; X₂₀ is 17W X₂₂ is 3W ± W; X₂₄ is 4W ± 2W; X₂₆ is 60W X₂₈ is 17W X₃₀ is 2W ± 0.5W; X₃₂ is

72W and θ₁₀ is 45° ± 15°. In addition, each

Leg B can vary in length from 0 to and each

Leg A can vary in length from 0 to tan (90-θ₁₀)

In Figure 5, W is between 0.064 mm and 0.12 mm;

X₃₄ is 2W ± 0.5W; X₃₆ is 58W X ₃₈ is 24W

θ₁₂ is 20° θ₁₄ is and n =

number of legs per 180° = 2 to 6.

In Figure 6, W is between 0.064 mm and 0.12 mm;

X₄₂ is 6W X₄₄ is 11W ± 5W; X₄₆ is 11W ± 5W; X₄₈ is 24W ± 10W; X₅₀ is 38W ± 13W; X₅₂ is 3W X₅₄ is

6W X

₅₆ is 11W ± 5W; X₅₈ is 7W ± 5W; X₆₀ is 17W ± 7W; X₆₂ is 28W ± 11W; X₆₄ is 24W ± 10W; X₆₆ is 17W ± 7W; X₆₈ is 2W ± 0.5W; θ₁₆ is 45° θ₁₈

is 45° ± 15°; and θ₂₀ is 45° ± 15°.

In Figure 6B W is between 0.064 mm and 0.12 mm,

X₇₂ is 8W X₇₄ is 8W X₇₆ is 12W ± 4W, X₇₈ is 8W ± 4W, X₈₀ is 24W ± 12W, X₈₂ is 18W ± 6W, X₈₄ is

8W X₈₆ is 16W ± 6W, X₈₈ is 24W ± 12W, X₉₀ is

18W ± 6W, X₉₂ is 2W ± 0.5W, θ₂₂ is 135° ± 30°, θ₂₄ is 90º ± 30°' θ26 is 45° ± 15º θ₂₈ is 45° ± 15º , 30 is

45° ± 15°, θ₃₂ is 45° ± 15°, θ₃₄ is 45° ± 15°, θ₃₆ is 45° ± 15°, and θ₃₈ is 45° ± 15°.

In Figure 7, the depicted spinneret orifice

contains two repeat units of the spinneret orifice depicted in Figure 3, therefore, the same dimensions for Figure 3 apply to Figure 7. Likewise, in Figure 8, the depicted spinneret orifice contains four repeat units of the spinneret orifice depicted in Figure 3, therefore, the same dimension for Figure 3 applies to Figure 8.

Figure 16 illustrates the method for determining the shape factor, X, of the fiber cross-section. In Figure 16, r = 37.5 mm, P_w = 355.1 mm, D = 49.6 mm;

thus, for the fiber cross-section of Figure 16:

The tobacco modifying agent useful in the present invention can be any such agent used in tobacco products and/or tobacco substitute products where delivery of such agent to the user is desirable. Such agents typically modify the taste and/or aroma of smoking products. Thus, the tobacco modifying agent can be a flavorant or other aromatic material including both naturally occurring and synthetic materials regardless of their hydrophobic or hydrophilic nature. Examples of such tobacco modifying agents include flavorants, synergistic flavor enhancers, physiological coolants and other mouth or throat stimulants, with flavorants being preferred.

Examples of flavorants include tobacco note

flavorants comprising naturally occurring materials such as aqueous (hydrophilic) tobacco extracts (as disclosed in U.S. Patent 3,316,919 incorporated herein by

reference in its entirety) and aromatics (as disclosed in U.S. Patent 3,424,171 incorporated herein by

reference in its entirety), and synthetic materials which augment the minty, camphoraceous, spicy, peppery, fruity, flowery, woody, green, or other tobacco flavor and aroma notes. Other flavorants contemplated for use in the invention include naturally occurring or

synthetic flavorants which introduce flavor notes that are not normally indigenous to tobacco such as the following which have been demonstrated to be useful on filters by U.S. Patent 3,144,024 (incorporated herein by reference in its entirety), wine, rum, coumarin, honey, vanilla, juniper, molasses, maple syrup, chocolate, menthol, and sugars. In addition, vanillin, licorice, anethole, anise, cocoa, cocoa and chocolate by products, sugars, humectants, eugenol, clove oil, triacetin, and other generally accepted cellulose acetate flavorant filter additives.

Examples of synergistic flavor enhancers include smoothers such as glutamates and nucleotides as

disclosed in U.S. Patent 3,397,700 (incorporated

herein by reference in its entirety) and 2

cyclohexylcyclohexanone as disclosed in U.S. Patent 3,342,186 (incorporated herein by reference in its entirety).

Examples of naturally occurring physiological coolants include mint oils, menthol, camphor and

camphoraceous compounds.

Examples of synthetic physiological coolants include synthetic menthol and menthol derivatives (the latter exemplified by menthol monoester disclosed in U.S. Patent 3,111,127 (incorporated herein by reference in its entirety), menthol acetals disclosed in U.S.

Patent 3,126,012 (incorporated herein by reference in its entirety), menthol ethers disclosed in U.S. Patent 3,128,772 (incorporated herein by reference in its entirety), menthol esters disclosed in U.S. Patent

3,136,319 (incorporated herein by reference in its entirety), synthetic camphor and camphoraceous compounds such as cyclohexenones and cyclohexanones disclosed in U.S. Patent 3,380,456 (incorporated herein by reference in its entirety), and synthetic coolants as disclosed in U.K. Patents 1,351,761 and 1,351,762 and U.S. Patents 4,296,255 and 4,230,688.

Examples of other mouth or throat stimulating compounds include either natural or synthetic compounds such as nicotine, and its derivatives, including, for example, nicotine complexes and salts disclosed in U.S. Patent 3,109,436 (incorporated herein by reference in its entirety).

A feature of the invention is the spontaneously wettable character of the preferred fibers used for the tobacco modifying agent delivery substrate and/or the selective removal additive substrate. Although not desired to be bound by any particular theory or

mechanism, it is believed that the ability of

spontaneously wettable fibers to transport and spread fluids on fibers having high surface areas which are not necessarily penetrated by the modifying agent is responsible for the high delivery efficiencies and high percentage of selective removal of unwanted substrates achieved by the combination of the invention. The invention is, therefore, not limited to a specific polymer or fiber treatment, such as fiber finish, or to a particular form of final fiber assemblage. Tobacco modifying agent delivery articles and/or selective removal additive delivery articles might, therefore, be made from fibers in any suitable form, including but not limited to, webs, continuous tows, and cut staple.

Also, webs can be powder, calendar or binder fiber bonded, and staple can be loose or as a sliver.

Although the preferred implementation of the invention is a filter-like article employed either alone or in a multi-component configuration such as in a combination with a conventional cellulose acetate filter plug in a dual filter arrangement, the physical form of the tobacco delivery article and/or selective removal delivery article is not thus limited. In addition, the invention is not limited in its uses to cigarettes and is likewise applicable to all smoking products including pipes, and even novel and as yet unconceived of aerosol sources. Thus, the combination of the present invention is preferably in the form of a tobacco smoke filter or material useful for the preparation thereof. Cigarette filters are especially preferred. Accordingly, the present invention is also directed to a tobacco smoke filter comprising the combination of the invention wherein said filter is in substantially cylindrical form having a length of about 5 to about 40 millimeters (mm), preferably about 10 to about 30 mm, and a diameter of about 15 to about 30 mm, preferably about 22 to about 25 mm. In a preferred, dual filter arrangement, the portion of the dual filter comprising the combination of the invention is preferably about 6 to about 15 mm.

The combination of the invention is useful for the efficient and uniform delivery of tobacco modifying agents. The combination of the invention is also useful for efficient and uniform selective removal of unwanted substances such as phenol or nicotine. The direct economic value of the invention results from cost savings achieved through reductions in the quantity of expensive agents, especially flavorants and selective removal additives, that are needed to achieve a desired organoleptic effect. Other benefits of the invention include increased shelf life, improved consistency of product taste which results from more constant delivery of the tobacco modifying agent over time, and improved efficiency of selective removal of unwanted substances.

To prepare the combination of the invention, the tobacco modifying agent (s) and/or selective removal additive of choice is applied, typically as a fluid, to an assemblage of fibers contemplated herein, especially spontaneously wettable fibers. Such assemblage can be, for example, a nonwoven web or continuous tow, which is then preferably made into a rod-like or cylindrical article using filter making technology that is well known to one skilled in the art. After application of the tobacco modifying agent(s) and/or selective removal additive to the fibers, the combination is optionally dried by conventional procedures, for example, air drying or oven drying, especially to remove excess solvent, if present. The rod-like article can be subdivided into segments of an appropriate length which are attached to an aerosol source such as the tobacco column of a conventional cigarette either alone or in conjunction with a conventional filter element, e.g., cellulose acetate filter, on the mouth and so as to give the appearance of a conventional cigarette filter. The resulting improvement in flavorant delivery performance achieved by the invention is exemplified in Figures 1, 17 and 18 for the implementations described in

Examples 14 and 15 hereof. The resulting improvement in selective delivery performance is described in

Example 16 hereof.

Figure 1 contrasts the delivery of the commonly used smoking article flavorant triacetin (glycerol triacetate) from identical fiber assemblages consisting of spontaneously wettable and non-spontaneously wettable (round) fibers of comparable filament denier. The figure clearly demonstrates the substantial flavorant delivery advantage achieved by the spontaneously

wettable fiber assemblage.

Figure 18 contrasts the delivery of the commonly used smoking article flavorant triacetin (glycerol triacetate) from equal pressure drop fiber assemblages consisting of spontaneously wettable and conventional cellulose acetate fibers. This figure shows that the flavorant delivery advantage achieved by the

spontaneously wettable fiber assemblage is even greater when compared to the performance of conventional

cellulose acetate fibers. Furthermore, Figure 19 shows that the delivery efficiency of the spontaneously wettable polyester fiber web filter segments for

glycerol triacetate is relatively constant over extended periods of storage, whereas the delivery efficiency of the conventional cellulose acetate filter decreases significantly.

For certain tobacco modifying agents, such as volatile flavorants, it may be desirable to apply such agents in a solution of a nonvolatile solvent in which the agent is highly soluble. An example of this

implementation is to prepare a solution of menthol in a sufficiently nonvolatile solvent such as triacetin, polyethylene glycol, or mineral oil. The flavorant, applied as a solution to the fiber assemblage, will remain on the assemblage dissolved in the solvent but will still be spread uniformly over the fibers in a way that results in its high delivery efficiency.

The amount of tobacco modifying agent in the combination of the invention (as well as assemblages made therefrom such as cigarette filters) will vary depending on, among other things, the nature of the particular fibers, the chemical nature and potency of the particular tobacco modifying agent, and the desired type of delivery of the agent. However, a typical amount of tobacco modifying agent is about 0.001 to about 100 percent, based on the weight of the fibers. If the tobacco modifying agent is present as a solid free of solvent, a preferred amount of agent is about 0.1 to about 50%, based on the weight of the fibers. If the tobacco modifying agent is present as a liquid, a preferred amount of agent is about 0.1 to about 10%, based on the weight of the fiber.

Regarding total delivery of tobacco modifying agent, the combination of the invention in a single component cigarette filter form preferably results in at least a 10% improvement, more preferably at least a 30% improvement, in delivery of such agent to the user as compared to a control filter using fibers of round cross-section.

The selective removal additives useful in the present invention are specific chemical compounds or mixtures of compounds that are applied to filter fibers to enhance the removal of certain compounds or classes of compounds from cigarette smoke. Selective removal additives may be fluids or solids. If solids are used, they are frequently applied to the filter medium as a solution in an appropriate solvent or as a suspension in an appropriate fluid medium.

Examples of fluid selective removal additives which are useful for removal of phenols include polyols and their esters such as diethyl citrate, glycerol

triacetate, triethylene glycol diacetate, poly (ethylene glycol) 400 or 600, and triethylene glycol.

Examples of fluid selective removal additives which are useful for removal of nicotine are glycerin and distilled monoglycerides derived from edible fats and glycerine, such as Myverol (trademark) and Myvatem

(trademark) sold by Eastman Chemical Company, a division of Eastman Kodak Company, Kingsport, TN.

Examples of solid selective removal additives that can be applied as solutions or suspensions in the appropriate fluid include salcomine, which is useful for selectively removing nitrogen oxides, zinc oxide, which is useful for selectively removing hydrogen cyanide, polyethyleneimine, which is useful for selectively removing aldehydes. Other generally useful additives include activated carbon, ion exchange resins, zeolites, waxes or starches.

The following examples are to illustrate the invention but should not be interpreted as a limitation thereon.

EXAMPLES

EXAMPLE 1 (Fiber Preparation)

Poly(ethylene terephthalate) (PET) polymer of 0.6

I.V. was used in this example. I.V. is the inherent viscosity as measured at 25°C at a polymer concentration of 0.50 g/100 milliliters (mL) in a suitable solvent such as a mixture of 60% phenol and 40% tetra-chloro- ethane by weight. The polymer was dried to a moisture level of ≤0.003 weight percent in a Patterson Conaform dryer at 120°C for a period of 8 hours. The polymer was extruded at 283°C through an Egan extruder, 1.5-inch (38.1 mm) diameter, with a length to diameter ratio of 28:1. The fiber was extruded through an eight orifice spinneret wherein each orifice is as shown in Figure 3 wherein W is 0.084 mm, X₂ is 4W, X₄ is 2W, X₆ is 6W, X₈ is 6W, X₁₀ is 7W, X₁₂ is 9W, X₁₄ is 10W, X₁₆ is 11W, X₁₈ is 6W, θ₂ is 0°, θ₄ is 45°, θ₆ is 30°, and θ₈ is 45°. The polymer throughput was about 7 pounds (lb)/hour

(3.18 kg/hour). The air quench system has a cross-flow configuration. The quench air velocity at the top of the screen was an average of 294 feet (ft)/minute (89.61 m/minute). At a distance of about 7 inches (177.8 mm) from the top of the screen the average velocity of the quench air was about 285 ft/minute (86.87 m/minute), and at a distance of about 14 inches (355.60 mm) from the top of the screen the average quench air velocity was about 279 ft/minute (85.04 m/minute). At about 21 inches (533.40 mm) from the top of the air screen the average air velocity was about 340 ft/minute (103.63 m/minute). The rest of the screen was blocked.

Spinning lubricant was applied via ceramic kiss rolls. The lubricant has a general composition as follows: it is a potassium lauryl phosphate (PLP) based lubricant having poly(ethylene glycol) 600 monolaurate (70% by weight) and polyoxyethylene (5) potassium lauryl

phosphate (30% by weight). An emulsion of the above lubricant with water (90%) was used as the spinning lubricant. The lubricant level on the fiber samples was about 1.5%. Fibers of 20 dpf (denier per filament in kg/m) were wound at 3,000 meters per minute (MPM) on a Barmag SW4SL winder. A photomicrograph of a

cross-section of this fiber is shown in Figure 9 (150x magnification). The single fiber was tested for spontaneous surface transportation of an aqueous

solution which was aqueous Syltint Poly Red (obtained from Milliken Chemicals) which is 80 weight % water and 20 weight % red colorant. The single fiber of 20 dpf (kg/m per filament) spontaneously surface transported the above aqueous solution. The following denier (kg/m) per filament PET fibers were also made at different speeds as shown in Table 1 below:

All the single fibers of above PET fiber with the denier (kgxiti) per filament of 20, 40, 60, 120, 240, and 400 spontaneously surface transported the aqueous solution of Syltint Poly Red liquid. The value of the "X" parameter (as defined hereinbefore) for these fibers was about 1.7. PET film of 0.02 inch (0.51 mm) thickness was compression molded from the same polymer as that used for making the above fiber. Contact angle of distilled water on the above film was measured in air with a contact angle goniometer. The contact angle was 71.7°. Another sample of the same film as above was sprayed with the same lubricant as used for making the fiber in this example at about 1.5% level. The contact angle of distilled water on the PET film sprayed with the lubricant was about 7°. Thus, the factor (1-X cos θ) in this case is (1-1.7 (cos 7°)) = -0.69, which is less than zero.

EXAMPLE 2 (Fiber Preparation)

Polyhexamethylene adipamide (nylon 66) was obtained from Du Pont [Zytel (trademark) 42]. The polymer was extruded at 279°C. A spinneret as shown in Figure 3 was used to form 46 denier (kg/rn) per filament fiber at 255 meters/minute speed. The specific dimensions of the spinneret orifices were the same as described in

Example 1 except that θ₂ was 30° instead of 0°. The quenching conditions were the same as those for

obtaining PET fiber as in Example 1. A photomicrograph of the fiber cross-section is shown in Figure 11 (150x magnification). The lubricant level on the fiber was about 1.8% by weight. The same lubricant as used in the PET fiber was used (Example 1). This nylon 66 fiber spontaneously transported the aqueous Syltint Poly Red solution on the fiber surface. The value of the "X" parameter for this fiber was about 1.9. Nylon 66 film of 0.02 inch (0.51 mm) thickness was compression molded from the same polymer as that used for making the fiber of Example 2. Contact angle of distilled water on the above film was measured in air with a contact angle goniometer. The contact angle was 64°. Another sample of the same film as above was sprayed with the same lubricant as used for making the fiber in this example at about the 1.8% level. The contact angle of distilled water on the nylon 66 film sprayed with the lubricant was about 2°. Thus, the factor (1-X cos 0) in this case is (1-1.9 (cos 2°)) = -0.9, which is less than zero. EXAMPLE 3 (Fiber Preparation)

Polypropylene polymer was obtained from Shell Company (Grade 5C14). It was extruded at 279°C. A spinneret as shown in Figure 3 was used to form

51 denier (kg/m) per filament fiber at 2,000 MPM speed. The specific dimensions of the spinneret orifices were the same as in Example 2. The quenching conditions were the same as those for obtaining PET fiber. A

photomicrograph of the fiber cross-section is shown in Figure 10 (375x magnification). The lubricant level on the fiber was 2.6%. The same lubricant as used in PET fiber was used (Example 1). The polypropylene fiber spontaneously transported the aqueous Syltint Poly Red solution on the fiber surface. This spontaneously transportable phenomenon along the fiber surface was also observed for a 10 denier (kg/m) per filament, single polypropylene fiber. The value of the "X" parameter for this fiber was about 2.2. Polypropylene film of 0.02 inch (0.51 mm) thickness was compression molded from the same polymer as that used for making the above fiber of Example 3. Contact angle of distilled water on the above film was measured in air with a contact angle goniometer. The contact angle was about 110°. Another sample of the same film as above was sprayed with the same lubricant as used for making the fiber in this example at about the 2.6% level. The contact angle of distilled water on the polypropylene film sprayed with the lubricant was 12°. Thus, the factor (1-X cos θ) in this case is -1.1, which is less than zero.

EXAMPLE 4 (Fiber Preparation)

Cellulose acetate (Eastman Grade CA 398-30,

Class I) was blended with PEG 400 polymer and small quantities of antioxidant and thermal stabilizer. The blend was melt extruded at 270°C. A spinneret as shown in Figure 3 was used to form 115 denier (kg/m) per filament fiber at 540 meters/minute speed. The specific dimensions of the spinneret orifices were the same as in Example 2. No forced quench air was used. The

lubricant level on the fiber was 1.6%. The same

lubricant as used in the PET fibers (Example 1) was used. The cellulose acetate fiber spontaneously

transported the aqueous Syltint Poly Red solution on the fiber surface. The value of the "X" parameter for this fiber was about 1.8.

EXAMPLE 5 (Comparative)

PET fiber of Example 1 was made without any

spinning lubricant at 20 denier (kg/m) per filament. A single fiber did not spontaneously transport the aqueous Syltint Poly Red solution along the fiber surface.

EXAMPLE 6 (Comparative)

PET fiber of circular cross-section was made. The denier (kg/m) per filament of the fiber was 20. It had about 1.5% of the lubricant used in Example 1. A single fiber did not spontaneously transport the aqueous

Syltint Poly Red solution along the fiber surface.

EXAMPLE 7 (Fiber Preparation)

Poly (ethylene terephthalate) (PET) fiber of

Example 5 (without any spinning lubricant) was treated with oxygen plasma for 30 seconds. Model "Plasmod" oxygen plasma equipment was used. Exciter power is provided by the RF generator operating at 13.56 MHz frequency. The plasma treatment was conducted at a constant level of 50 watts power. The oxygen plasma treated fiber spontaneously transported the aqueous Syltint Poly Red solution along the fiber. This fiber was tested again after washing five times and after 3 days and the spontaneously transportable behavior with the above aqueous solution was still observed. In order to determine the reduction in contact angle after the plasma treatment, a PET film of the same material as that of the fiber was subjected to the oxygen plasma treatment under the same conditions as those used for the fiber sample. The average contact angle of the oxygen plasma treated film with distilled water in air was observed to be 26° as measured by a contact angle goniometer. The corresponding contact angle for the control PET film (not exposed to the oxygen plasma) was 70°. The significant reduction in contact angle upon subjecting the untreated PET fiber to the oxygen plasma treatment renders it to be spontaneously surface

transportable for aqueous solutions.

EXAMPLE 8 (Fiber Preparation)

Poly(ethylene terephthalate) (PET) polymer of 0.6 IV was used in this example. It was extruded through a spinneret having eight orifices as shown in Figure 4 wherein W is 0.084 mm, X₂₀ is 17W, X₂₂ is 3W, X₂₄ is 4W, X₂₆ is 60W, X₂₈ is 17W, X₃₀ is 2W, X₃₂ is 72W, θ₁₀ is 45°, Leg B is 30W, and Leg A is 26W. The rest of the processing conditions were the same as those described in Example 1. A 100 denier (kg/m) per filament fiber was spun at 600 MPM. A sketch of the cross-section of the fiber is shown in Figure 12. The lubricant level on the fiber was about 1%. The same lubricant as used in Example 1 was used. The above fiber spontaneously transported the aqueous Syltint Poly Red solution along the fiber surface. The value of the "X" parameter for this fiber was 1.5. EXAMPLE 9 (Fiber Preparation)

Poly(ethylene terephthalate) polymer of 0.6 IV was used in this example. It was extruded through a

spinneret having eight orifices as shown in Figure 5 wherein W is 0.10 mm, X₃₄ is 2W, X₃₆ is 58W, X₃₈ is 24W, θ₁₂ is 20°, θ₁₄ is 28°, and n is 6. The rest of the extruding and spinning conditions were the same as those described in Example 1. A photomicrograph of the fiber cross-section is shown in Figure 13 (585x magnification). A 20 denier (kg/m) per filament fiber was spun at 3000 MPM. The lubricant level on the fiber was about 1.7%. The same lubricant as used in Example 1 was used. The above fiber spontaneously transported the aqueous Syltint Poly Red solution along the fiber surface. The value of the "X" parameter for this fiber was about 2.4.

EXAMPLE 10 (Fiber Preparation)

Poly(ethylene terephthalate) (PET) polymer of about 0.6 IV was used in this example. The polymer was extruded through a spinneret having four orifices as shown in Figure 7 wherein the dimensions of the orifices are repeats of the dimensions described in Example 2. The rest of the processing conditions were the same as those described in Example 1 unless otherwise stated. A 200 denier (kg-/m) per filament fiber was spun at

600 MPM. The polymer throughput was about 7 lbs/hr (3.18 kg/hr) . An optical photomicrograph of the fiber is shown in Figure 14 (150x magnification). The

lubricant level on the fiber was 2.0%. The same

lubricant as used in Example 1 was used. The above fiber spontaneously transported the aqueous Syltint Poly Red solution along the fiber surface. The value of the "X" parameter for this fiber was about 2.2. EXAMPLE 11 (Fiber Preparation)

Poly(ethylene terephthalate) (PET) polymer of 0.6 IV was used in this example. The polymer was extruded through a spinneret having two orifices as shown in Figure 8 wherein the dimensions of the orifices are repeats of the dimensions described in Example 2. The rest of the processing conditions were the same as those described in Example 1. A 364 denier (kg/m) per

filament fiber was spun at 600 MPM. The cross-section of the fiber is shown in Figure 15 (150x magnification) . The lubricant level on the fiber was about 2.7%. The same lubricant as used in Example 1 was used. The above fiber spontaneously transported the aqueous Syltint Poly Red solution along the fiber surface. The value of the "X" parameter for this fiber was 2.1.

EXAMPLE 12 (Fiber Preparation)

Poly(ethylene terephthalate) (PET) polymer of 0.6 IV was used in this example. It was extruded through a spinneret having eight orifices as shown in Figure 6 wherein W is 0.10 mm, X₄₂ is 6W, X₄₄ is 11W, X₄₆ is 11W, X₄₈ is 24W, X₅₀ is 38W, X₅₂ is 3W, X₅₄ is 6W, X₅₆ is 11W, X₅₈ is 7W, X₆₀ is 17W, X₆₂ is 28W, X₆₄ is 24W, X₆₆ is 17W, X₆₈ is 2W, θ₁₆ is 45°, θ₁₈ is 45°, and θ₂₀ is 45°. The rest of the processing conditions were the same as those described in Example 1. A 100 denier (kg/m) per filament fiber was spun at 600 MPM. The cross-section of the fiber is shown in Figure 17. The lubricant level on the fiber was about 1%. The same lubricant as used in Example 1 was used. The above fiber spontaneously transported the aqueous Syltint Poly Red solution along the fiber surface. The value of the "X" parameter for this fiber was 1.3. EXAMPLE 13 (Fiber Preparation)

PET polymer of 0.6 I.V. is used in this example. It is extruded through a spinneret having 8 orifices as shown in Figure 6B wherein W is 0.10 mm, X₇₂ is 8W, X₇₄ is 8W, X₇₆ is 12W, X₇₈ is 8W, X₈₀ is 24W, X₈₂ is 18W, X₈₄ is 8W, X₈₆ is 16W, X₈₈ is 24W, X₉₀ is 18W, X₉₂ is 2W, θ₂₂ is 135°, θ₂₄ is 90°, θ₂₆ is 45°, θ₂₈ is 45°, θ₃₀ is 45°, θ₃₂ is 45°, θ₃₄ is 45°, θ₃₆ is 45° and θ₃₈ is 45°. A 20 denier (kg/m) per filament fiber is spun at 3,000 m/ min. The rest of the processing conditions are the same as those used in Example 1. The lubricant level on the fiber is about 1%. The cross-section of the fiber is shown in Figure 17B. This fiber

spontaneously transports the aqueous Syltint Poly Red solution along the fiber surface. The "X" value for this fiber is about 2.1.

EXAMPLE 14 (Example of the Invention)

Spontaneously wettable polyester fibers were melt spun from polyethylene terephthalate polymer according to the methods described in Example 1. The value of the X parameter (as defined hereinbefore) for these fibers was about 1.8. A yarn of these fibers was then drafted to 5.5 denier (kg/m) per filament, heat set at about 180°C, crimped to about 7 or 8 crimps per inch (25.4 mm), and cut into 2-inch (50.8 mm) long staple fibers. The resulting staple fibers were carded and bonded with about 15 weight % Eastobond (trademark) FA-252 polyester adhesive in powder form into a nonwoven web with a density of about 19 grams per square yard (22.71

grams/square meter). Round cross section fiber webs to be used as controls were made by an identical process except that the fibers were melt spun through spinnerets with round holes. The resulting round and spontaneously wettable polyester fiber webs were slit lengthwise into pieces approximately 12 inches (304.80 mm) wide which were then cut into 24-inch (609.60 mm) long sections. The

resulting 12-inch (304.80 mm) wide by 24-inch (609.60 mm) long web sections weighed approximately 4 grams each. Glycerol triacetate, also referred to as

triacetin flavorant, either in its pure form or as a 10, 20, or 50 weight % solution in ethanol, was applied in roughly equal quantities to both round and spontaneously wettable fiber web sections using an aerosol sprayer. The web sections were air dried overnight to remove the residual ethanol.

The dried web sections were pulled lengthwise into drinking straws which were about 23 mm in circumference and each straw was cut into 21-mm long segments. The 21-mm long round fiber web filled straw segments

contained about 150 mg of web and had an average

pressure drop of about 28 mm of water when measured at a flow rate of 17.5 cc/sec. of air. The 21-mm long spontaneously wettable fiber web filled straw segments also contained about 150 mg of web but had an average pressure drop of about 55 mm of water when measured at a flow rate of 17.5 cc/sec. of air. Each 21-mm segment contained between 2 and 18 mgs of glycerol triacetate depending upon the application rate.

The 21-mm long web filled straw segments were then attached to 63-mm long blended tobacco columns that had been cut off a popular king-sized domestic cigarette brand, and the resulting cigarettes were smoked

according to CORESTA Standard Method No. 10 entitled "Machine Smoking of Cigarettes and Determination of Crude and Dry Smoke Condensate". Experimental

cigarettes were smoked in groups such that one glass fiber filter pad was used to collect the smoke condensate from five cigarettes. Each glass fiber filter pad was then extracted with 15 ml of isopropanol containing 0.4 mg/ml hexadecane as an internal standard. The glycerol triacetate present in the isopropanol extract of the condensate from each glass fiber pad was then quantitatively determined by capillary gas

chromatography.

The performance of the invention for delivering glycerol triacetate is reported in Figure 1. The reported delivery efficiency is defined as the

percentage of the flavorant present on the fiber web filled straw segment before smoking that was delivered to the glass fiber filter pad by smoking the

experimental cigarettes. The term "4SW" represents fibers capable of spontaneously transporting water on the surfaces thereof.

EXAMPLE 15 (Example of the Invention)

Spontaneously wettable polyester fibers were melt spun from polyethylene terephthalate polymer according to the methods described in Example 1. The value of the X parameter (as defined hereinbefore) for these fibers was about 1.7. A yarn of these fibers was then drafted to 10.3 denier (kg/m) per filament, heat set at about 180 degrees centigrade, crimped to about 7 or 8 crimps per inch (25.4 mm), lubricated with poly(ethylene) 600 monolaurate lubricant, and cut into 2 inch (50.8 mm) long staple fibers. The spontaneously wettable staple fibers were blended with about 20 weight % Kodel

(trademark) 410 amorphous polyester binder fiber, carded and thermally bonded into a nonwoven web with a density of about 35 grams per square yard (41.53 grams/square meter). The resulting web was then slit into sections 9.4 inches (238.76 mm) wide and wound onto rolls about 1000 linear yards (914.40 meters) long. Rolls of spontaneously wettable polyester fiber web were processed into filter rods in the following manner. An Eastman Miniature filter tow processing unit was used to unwind the web from the roll, to quantitatively apply glycerol triacetate to the web at each of the two target application rates, and to control the rate of delivery of the web to the next step of the process. A Molins PM-2 filter rod making machine was then used to fold the web into rod shaped cylinders which were wrapped with Ecusta 646 plugwrap. The resulting filter rods were cut into 21 mm long segments which were 24.5 mm in

circumference, contained about 178 mg of nonwoven web, and had an average pressure drop of about 27 mm of water when measured at a flow rate of 17.5 cc/sec of air.

Depending on the rate of application, each filter segment contained either 2.4 mg or 5.6 mg of glycerol triacetate which, when expressed as a percentage of the total filter weight, corresponded to levels of 1.3 and 2.8 weight percent respectively.

As a comparison, flavored control filters were made in the conventional manner from 3.3 denier (kg/m) per filament, 39,000 total denier (kg/m), Y cross section, Estron (trademark) solution spun cellulose acetate filter tow. The 21 mm long filter segments were 24.5 mm in circumference, contained 120 mg of filter tow, and had an average pressure drop of about 65 mm of water when measured at a flow rate of 17.5 cc/sec of air.

Each filter segment contained 10.3 mg of glycerol triacetate which, when expressed as percentage of the total filter weight, corresponded to a level of 7.0 weight percent.

The spontaneously wettable polyester fiber web filter segments were then placed in sealed glass jars and stored for intervals consisting of 10, 18, 28, 39, 52, 66, and 82 days. At the end of each storage interval, the filters were attached to 63 mm long blended tobacco columns that had been cut off of a popular King sized domestic cigarette brand and the resulting cigarettes were smoked acccording to CORESTA Standard Method No. 10 entitled "Machine Smoking of Cigarettes and Determination of Crude and Dry Smoke Condensate". The cellulose acetate control filters were stored for intervals of 3, 7, 14, 21, 28, 42, 56, and 84 days prior to smoking.

Both experimental and control cigarettes were smoked in groups such that one glass fiber filter pad was used to collect the smoke condensate from 4

cigarettes. Each glass fiber filter pad was then extracted with 15 ml of isopropanol containing 0.4 mg/ml hexadecane as an internal standard. The glycerol triacetate present in the extract of the condensate from each glass fiber pad was then quantitatively determined by capillary gas chromatography.

Figure 18 reports the performance of the invention for achieving consistantly higher delivery efficiencies of glycerol triacetate than the control cellulose acetate filters. The delivery efficiency reported in Figure 18 is defined as the percentage of the glycerol triacetate present on the filter segment before smoking that was delivered to the glass fiber pad by smoking the experimental and control cigarettes. Figure 2 shows that the delivery efficiency of the spontaneously wettable polyester fiber web filter segments for glycerol triacetate was 2 to 3 times greater than the delivery efficiency of the conventional cellulose acetate filter segments initially and 3 to 4 times greater by the end of the experiment. These higher delivery efficiencies permit significant reductions in the amount of flavorant that must be used to achieve a desired delivery. Figure 19 reports the performance of the invention for maintaining a constant delivery efficiency of glycerol triacetate over extended periods of storage. The delivery efficiency change reported in Figure 3 is defined as the percentage change in delivery efficiency relative to the delivery efficiency anticipated from a freshly made filter. Figure 19 shows that the delivery efficiencies of the two spontaneously wettable polyester fiber web filter segments for glycerol triacetate are virtually independent of storage time and, therefore, show little change, whereas the conventional cellulose acetate filter segments loose almost half of their already lower delivery efficiency during the time spanned by this experiment.

EXAMPLE 16 (Example of the Invention)

Spontaneously wettable polyester fibers were melt spun from polyethylene terephthalate polymer according to the methods described in Example 1. The value of the X parameter (as defined hereinbefore) for these fibers was about 1.8. A yarn of these fibers was then drafted to 5.5 denier (kg/m) per filament, heat set at about 180 degrees centigrade, crimped to about 7 or 8 crimps per inch (25.4 mm), and cut into 2 inch (50.8 mm) long staple fibers. The resulting staple fibers were carded and bonded with about 15 weight % Eastobond FA-252 polyester adhesive powder into a nonwoven web with a density of about 19 grams per square yard (22.71

grams/square meter). Round cross section fiber webs to be used as controls were made by an identical process except that the fibers were melt spun through spinnerets with round holes.

The resulting round and spontaneously wettable polyester fiber webs were slit lengthwise to widths of 15 and 12 inches (381.00 and 304.80 mm), respectively. The round webs were slit to a wider width in order to better match the pressure drops of the resulting

filters. Selective removal additives consisting of either glycerol triacetate or poly(ethylene glycol) 600 were applied to each web at a level of 7 weight percent using an aerosol sprayer. Glycerol triacetate was applied to the webs in pure form but, because of its higher viscosity, poly(ethylene glycol) 600 was applied as a 10% aqueous solution. The poly(ethylene glycol) 600 treated webs were dried in an oven at 60 degrees centigrade for 1 hour after spraying to remove excess water. All of the treated webs were allowed to air dry overnight to remove residual volatiles.

The dried web sections were pulled lengthwise into drinking straws which were about 23 mm in circumference and each straw was cut into several 21 mm long segments. Filters were made in this manner to achieve a target pressure drop of about 70 mm of water when measured at a flow rate of 17.5 cc/sec of air. Because of differences in the relative abilities of the round and 4SW fiber webs to generate pressure drop, filters made from these two types of web contained different quantities of coated substrate. To achieve the target pressure drop, 21 mm long filters required about 210 mg of coated round fiber PET web and about 160 mg of coated 4SW fiber web.

As an additional comparison, straw filters were also made from a 3.3 denier (kg/m) per filament, 39,000 total denier, Y cross section, Estron solution spun cellulose acetate filter tow that had been treated with either glycerol triacetate or poly(ethylene glycol) 600. The resulting 21 mm long filter tips were 23 mm in circumference, contained about 130 mg of treated

cellulose acetate filter tow, and had an average

pressure drop of about 75 mm of water when measured at a flow rate of 17.5 cc/sec of air. Each filter segment contained between 8 and 9 mg of either glycerol

triacetate or poly (ethylene glycol) 600 which,

expressed as percentage, corresponds to an application level of 7.0 weight percent.

The 21 mm long treated straw filters were attached to 63 mm long blended tobacco columns that had been cut off of a popular King sized domestic cigarette brand and the resulting cigarettes were smoked acccording to CORESTA Standard Method No. 10 entitled "Machine Smoking of Cigarettes and Determination of Crude and Dry Smoke Condensate". Experimental cigarettes of a given type were smoked in groups such that one glass fiber filter pad was used to collect the smoke condensate from 5 cigarettes. The selective removal efficiency of the filters was then determined by measuring the amount of phenol present in the glass fiber filter pads and the freshly smoked cigarette filters.

In order to measure the phenol present, the glass fiber filter pads and cigarette filters were both separately extracted with diethyl ether and the

resulting extracts were concentrated, purified, and quantitately measured using gas chromatography. The percentage of selective phenol removal reported herein is defined as 100 times the amount of phenol on the cigarette filters divided by the sum of the amount of phenol on the cigarette filters and the amount of phenol on the glass fiber filter pad.

The performance of the invention for the selective removal of phenol from cigarette smoke is reported in Table 1. In all cases, the application of selective removal additives such as glycerol triacetate and poly (ethylene glycol) 600 to 4SW PET fiber web produced filters with higher selective removal efficiencies for phenol than were obtained when round PET fiber web or Estron filter tow were used as filter substrates. This superior phenol removal efficiency was obtained even though the 4SW PET fiber web filters had consistantly lower pressure drops than the filters made from either round PET fiber web or Estron filter tow and lower weights than filters made from round PET fiber web.

The invention has been described in detail with particular reference to the preferrred embodiments thereof, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention. All of the U.S. patents cited herein are hereby incorporated herein by reference in their entirety.

Claims

We Claim: 1. A combination comprising:

(A) at least one fiber having at least one

continuous groove wherein said fiber has a cross-section having a shape factor X that satisfies the following equation

wherein

P is the perimeter of the fiber and r is the radius of the circumscribed circle circumscribing the fiber cross-section and D is the minor axis dimension across the fiber cross-section, and

(B) at least one tobacco modifying agent.

The combination of Claim 1 wherein for the fiber of component (A), is greater than 1.

3. The combination of Claim 1 wherein for the fiber of component (A) is between 1.5 and 5.

4. The combination of Claim 1 wherein for the fiber of component (A) X is greater than 1.2.

5. The combination of Claim 1 wherein for the fiber of component (A) X is greater than 2.5. 6. The combination of Claim 1 wherein for the fiber of component (A) X is greater than 4.

7. The combination of Claim 1 wherein the fiber of component (A) has a single fiber denier (kg/m) of between 1 and 1,000. 8. The combination of Claim 1 wherein the fiber of

component (A) has a single fiber denier (kg/m) of between 5 and 70.

9. The combination of Claim 3 wherein the fiber of

component (A) has a single fiber denier (kg/m) of between 5 and 70.

10. The combination of Claim 1 wherein the fiber of

component (A) is comprised of a material selected from the group consisting of a polyester,

polypropylene, polyethylene, a cellulose ester, and a nylon.

11. The combination of Claim 1 having a plurality of the fiber of component (A) in the form of webs, continuous tows, and cut staple.

12. The combination of Claim 1 wherein said tobacco

modifying agent is a hydrophobic or hydrophilic material.

13. The combination of Claim 1 wherein said tobacco modifying agent is a flavorant, a synergistic flavor enhancer, a physiological coolant or another mouth or throat stimulant.

14. The combination of Claim 1 wherein said tobacco modifying agent is a flavorant.

15. The combination of Claim 1 wherein said tobacco modifying agent is an aqueous tobacco extract, aromatic tobacco extract, rum, coumarin, honey, vanilla, wine, juniper, molasses, maple syrup, chocolate, menthol, sugars, vanillin, licorice, anethole, anise, cocoa, cocoa and chocolate by products, sugars, humectants, eugenol, clove oil, triacetin, glutamates, nucleotides, 2-cyclohexyl- cyclohexanone, mint oil, menthol, camphor, camphoraceous compounds, menthol derivatives, or nicotine or its derivatives.

16. The combination of Claim 1 wherein the amount of component (B) is 0.001 to 100 percent based on the weight of component (A).

17. The combination of Claim 1 further comprising (C), a selective removal additive. 18. The combination of Claim 17 wherein said selective removal additive is a liquid.

19. The combination of Claim 18 wherein said liquid comprises polyols, ester of polyols, or

combinations thereof.

20. The combination of Claim 19 wherein polyols and esters of polyols comprise diethyl citrate, glycerol triacetate, triethylene glycol diacetate, poly(ethylene glycol) 400 or 600, triethylene glycol, glycerin, distilled monoglycerides derived from edible fats and glycerin.

21. The combination of Claim 17 wherein said selective removal additive is a solid.

22. The combination of Claim 21 wherein said solid comprises salcomine, zinc oxide, polyethyleneimine, activated carbon, ion exchange resins, zeolites, waxes or starches.

23. A combination comprising:

(A) at least one fiber having at least one

continuous groove which is capable of spontaneously transporting water on the surface thereof wherein said fiber satisfies the equation

(1-X cos θ_a) < 0,

wherein

θ_a is the advancing contact angle of water measured on a flat film made from the same material as the fiber and having the same surface treatment, if any,

X is a shape factor of the fiber

cross-section that satisfies the following equation

wherein

P_w is the wetted perimeter of the fiber and r is the radius of the circumscribed circle circumscribing the fiber cross-section and D is the minor axis dimension across the fiber cross-section, and

(B) at least one tobacco modifying agent.

24. The combination of Claim 23 wherein for the fiber of component (A), is greater than 1.

25. The combination of Claim 23 wherein for the fiber of component (A) is between 1.5 and 5.

26. The combination of Claim 23 wherein the fiber of component (A) satisfies the equation (1-X cos θ_a) ≤ -0.3,

wherein γ_LA is the surface tension of water in air in dynes/cm, ρ is the fiber density in grams/cc, and dpf is the denier in kg/m of the single fiber.

27. The combination of Claim 23 wherein for the fiber of component (A) X is greater than 1.2.

28. The combination of Claim 23 wherein for the fiber of component (A) X is greater than 2.5.

29. The combination of Claim 23 wherein for the fiber of component (A) X is greater than 4. 30. The combination of Claim 23 wherein the fiber of component (A) has a single fiber denier (kg/m) of between 1 and 1,000.

31. The combination of Claim 23 wherein the fiber of component (A) has a single fiber denier (kg/m) of between 5 and 70.

32. The combination of Claim 23 wherein the fiber of component (A) has a single fiber denier (kg/m) of between 5 and 70.

33. The combination of Claim 23 wherein the fiber of component (A) is comprised of a material selected from the group consisting of a polyester, polypropylene, polyethylene, a cellulose ester, and a nylon.

34. The combination of Claim 23 wherein said fiber of component (A) is comprised of a polyester having coated thereon a layer of a hydrophilic lubricant.

35. The combination of Claim 34 wherein said polyester is poly(ethylene terephthalate) and said

hydrophilic lubricant is a potassium lauryl phosphate based lubricant comprising 70 weight percent poly(ethylene glycol) 600 monolaurate which is uniformly applied at a level of at least 0.05% by weight of the total fiber.

36. The combination of Claim 23 wherein for said fiber of component (A) the width of each groove in the fiber cross-section at any depth in the groove is equal to or less than the width of the groove at its mouth.

37. The combination of Claim 23 having a plurality of the fiber of component (A) in the form of webs, continuous tows, and cut staple.

38. The combination of Claim 23 wherein said tobacco modifying agent is a hydrophilic material.

39. The combination of Claim 38 wherein said tobacco modifying agent is a flavorant.

40. The combination of Claim 23 wherein the amount of component (B) is 0.001 to 100 percent based on the weight of component (A).

41. A combination comprising:

(A) at least one fiber having at least one

continuous groove which is capable of spontaneously transporting n-decane on the surface thereof wherein said fiber satisfies the equation

(1-X cos θ_a) < 0,

wherein

X is a shape factor of the fiber

cross-section that satisfies the following equation

wherein

(B) at least one tobacco modifying agent.

42. The combination of Claim 41 wherein for the fiber ooff component (A), is greater than 1,

43. The combination of Claim 41 wherein for the fiber of component (A) is between 1.5 and 5.

44. The combination of Claim 41 wherein for the fiber of component (A) X is greater than 1.2.

45. The combination of Claim 41 wherein for the fiber of component (A) X is greater than 2.5.

46. The combination of Claim 41 wherein for the fiber of component (A) X is greater than 4.

47. The combination of Claim 41 wherein the fiber of component (A) has a single fiber denier (kg/m) of between 1 and 1,000.

48. The combination of Claim 41 wherein the fiber of component (A) has a single fiber denier (kg/m) of between 5 and 70. 49. The combination of Claim 43 wherein the fiber of component (A) has a single fiber denier (kg/m) of between 5 and 70.

50. The combination of Claim 41 wherein the fiber of component (A) is comprised of a material selected from the group consisting of a polyester,

polypropylene, polyethylene, a cellulose ester, and a nylon. 51. The combination of Claim 41 wherein said fiber of component (A) is comprised of a polyester having coated thereon a layer of a hydrophobic lubricant.

52. The combination of Claim 51 wherein said polyester is poly(ethylene terephthalate) and said

hydrophobic lubricant is mineral oil which is uniformly applied at a level of at least 0.05% by weight of the total fiber.

53. The combination of Claim 41 having a plurality of the fiber of component (A) in the form of webs, continuous tows, and cut staple.

54. The combination of Claim 41 wherein said tobacco modifying agent is a hydrophobic material.

55. The combination of Claim 54 wherein said tobacco modifying agent is a flavorant.

56. The combination of Claim 41 wherein the amount of component (B) is 0.001 to 100 percent based on the weight of component (A). 57. A tobacco smoke filter comprising a combination comprising:

(A) a plurality of fibers wherein each fiber of said plurality has at least one continuous groove wherein said fiber has a cross-section having a shape factor X that satisfies the following equation

wherein

(B) at least one tobacco modifying agent.

58. The tobacco smoke filter of Claim 57 in

substantially cylindrical form having a length of 5 to 40 mm and a diameter of 15 to 30 mm.

59. The tobacco smoke filter of Claim 57 in

substantially cylindrical form having a length of 10 to 30 mm and a diameter of 22 to 25 mm.

60. The tobacco smoke filter of Claim 57 which is a

cigarette filter.

61. The tobacco smoke filter of Claim 57 which is a

multicomponent configuration.

62. The tobacco smoke filter of Claim 57 which is in a dual configuration with a conventional cellulose acetate filter component. 63. A cigarette comprising the tobacco smoke filter of Claim 57.

64. A tobacco smoke filter comprising a combination

comprising:

(A) a plurality of fibers wherein each fiber of said plurality has at least one continuous groove which is capable of spontaneously transporting water on the surface thereof wherein said fiber satisfies the equation

(1-X cos θ_a < 0,

wherein

X is a shape factor of the fiber

cross-section that satisfies the following equation wherein

(B) at least one tobacco modifying agent.

65. The tobacco smoke filter of Claim 64 in

66. The tobacco smoke filter of Claim 64 in

67. The tobacco smoke filter of Claim 64 which is a

cigarette filter. 68. The tobacco smoke filter of Claim 64 which is a

multicomponent configuration.

69. The tobacco smoke filter of Claim 64 which is in a dual configuration with a conventional cellulose acetate filter component.

70. A cigarette comprising the tobacco smoke filter of Claim 64. 71. A tobacco smoke filter comprising a combination

comprising:

(A) a plurality of fibers wherein each fiber of said plurality has at least one continuous groove which is capable of spontaneously transporting n-decane on the surface thereof wherein said fiber satisfies the equation

(1-X cos θ_a) < 0,

wherein

X is a shape factor of the fiber

cross-section that satisfies the following equation

wherein

(B) at least one tobacco modifying agent.

72. The tobacco smoke filter of Claim 71 in

73. The tobacco smoke filter of Claim 71 in

74. The tobacco smoke filter of Claim 71 which is a cigarette filter. 75. The tobacco smoke filter of Claim 71 which is a multicomponent configuration.

76. The tobacco smoke filter of Claim 71 which is in a dual configuration with a conventional cellulose acetate filter component.

77. A cigarette comprising the tobacco smoke filter of Claim 71.