BACKGROUND OF THE INVENTION Foods, particularly ground meats, contain a large amount of water or other aqueous liquids and grease. Persons cooking such foods attempt to remove the grease for many reasons, including improved taste and nutritional concerns. Convenient methods for removing the grease from the food include spooning the grease off. refrigerating and removing the solidified grease, draining the food through a colander, or blotting the food with a paper towel. These methods are inconvenient and/or ineffective in removing grease.

Another apparatus for removing grease from foods is a low fat electric grill, such as the grill that is currently marketed in the U. S. under the brand trade name of the GEORGE FOREMAN GRILLE. These electric grills have a sloped and slotted cooking surface that allows grease melted during cooking to drip away from the food, into the slots, and then down into the sloped surface. However, these electric grills are relatively expensive. Additionally, these grills are bulky and thus take up a lot of surface space in a kitchen. Also, the grills cannot be used with foods such as soups and stews.

Pads for absorbing grease from foods are well known in the art. For example, some pads are made with a shell of spunbond single-component fiber comprising polypropylene and a filling of melt-blown single-component fiber also comprising polypropylene. Other pads are made of hydro- entangled single-component fiber comprising polypropylene.

However, existing absorbent pads have three significant limitations. First, some existing absorbent pads absorb water and other aqueous liquids and grease from the food. This is inefficient and undesirable because part of the absorbent capacity is utilized by the aqueous liquids, thereby leaving reduced capacity to absorb a significant quantity of grease. For example, these pads would suffer from a reduced capacitv for applications such as, but not limited to, removing grease from soup. Second, such existing absorbent pads typically may only be used in foods that are cooked at relatively low temperatures (e. g. no more than about 120 degrees C) such as, but not limited to, soups and stews. At higher temperatures, these absorbent pads can melt or shrivel up to a distorted configuration and therefore no longer efficiently absorb grease. However, the temperature for cooking foods in a frying pan, such as, but not limited to, hamburger, sausage, chili, or bacon, often reaches about 175 degrees C and above, well above the web integrity temperature of some existing absorbent pads. Third, some existing pads release lint during use, which can give the food both an unsatisfactory appearance and also could potentially be ingested with the food.

SUMMARY OF THE INVENTION The present invention provides an absorbent fibrous web for use in the preparation of food containing grease and aqueous liquids, the web being oleophilic, preferably hvdrophobic, resilient at high temperatures, and has low linting. The absorbent fibrous web of entangled fibers is comprised of at least about 55% bicomponent fibers having an oleophilic sheath and a core material with sufficient heat stability to maintain web integrity at a temperature higher than the sheath alone.

BRIEF DESCRIPTION OF THE DRAWINGS While the specification concludes with claims particularly pointing out and distinctly claiming the present invention, it is believed that the present invention will be better understood from the following description in conjunction with the accompanying drawings in which like reference numerals identify identical elements and wherein: FIG. 1 is an enlarged cross-sectional view of one form of a bicomponent fiber according to the present invention ; FIG. 2 is a perspective view of an embodiment of an absorbent fibrous web ; and FIG. 3 is a perspective view of an embodiment of an absorbent fibrous web having multiple layers heat sealed together and perforated along a central heat seal.

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a fibrous web for absorbing grease comprised of bicomponent fibers that are oleophilic. hydrophobic and have sufficient heat stability to withstand the high temperatures normally encountered during food preparation (typically approximately about 120 degrees C and up to about 200 degrees C in a frying pan), are cost effective and have low linting. The term"grease"generally refers to fats and/or oils, such as, but not limited to, the organic compounds that are energy-rich and occur widely in animal tissue and in the nuts, seeds, and fruits of plants, or any of several mineral and synthetic substances. The term"oleophilic"is defined as having an affinity for grease. An oleophilic web, as used herein, refers to a web that absorbs a drop of grease, such as, but not limited to, vegetable oil, on its surface in five seconds or less. Hydrophobic, as used herein, refers to a material that preferentially absorbs oil over aqueous liquids. However, the term"hydrophobic"may also encompass some aqueous liquid absorption.

Some aqueous liquid absorption is preferential because when aqueous liquid remains in the cooking container in foods that are not aqueous based, e. g. ground beef in a frying pan, the user of the absorbent web perceives that grease was not effectively absorbed.

Terms relating to fibers and web structures as used herein are defined consistently with descriptions contained in The Nonwoven Handbook (1998, by INDA), which is herein incorporated by reference. The term"bicomponent"as used herein refers to the presence of any two discrete structural portions of a fiber. The two discrete structural portions will generally be made of different chemical compositions. While other forms of bicomponent fibers are possible. the instant invention is concerned with"sheath-core"bicomponent fibers wherein a sheath substantially (i. e. at least 90%) covers a core, either concentrically or biased.

Generally, materials having greater oleophilic and hydrophobic properties lack sufficient heat stability to maintain web integrity at high temperatures, while more heat resistant materials typically lack such hydrophobic properties. Surprisingly. a"sheath-core"bicomponent form functions to provide a fiber that is both oleophilic and hydrophobic (the sheath) and also maintains structural integrity at high temperatures (the core). The oleophilic sheath has an affinity for grease, which allows the grease to coat the individual fibers, and also for the fibrous web to hold the grease in the interstitial voids between the fibers. The sheath's hydrophobicity ensures that the sheath's capacity to absorb a significant quantity of grease is not diminished because aqueous liquids are utilizing a significant portion of the absorbent capacity of the fibrous web. The core material should have sufficient heat stability to maintain web integrity up to at least about 175 degrees C, and more preferably at least about 200 degrees C. The phrase"sheath alone"refers to a fiber that is the same size and shape of a bicomponent fiber, but 100% of the fiber is comprised of the sheath material. The term"web integrity"refers to the ability for the web to remain suitable for use in food products at elevated temperatures and the absorption properties of the web described herein are retained.

The sheath material is capable of being formed into a fiber and is preferably oleophilic and hydrophobic. The material may include, but is not limited to, polyolefins such as polypropylene (PP), polyethylene (PE), poly 4-methylpentene (PMP), or blends thereof. Preferably, the sheath material is polypropylene (PP). Alternatively, the sheath material is a blend of polypropylene (PP) and poly 4-methylpentene (PMP).

The core material is capable of being formed into a fiber and have sufficient heat stability to maintain web integrity up to at least about 120 degrees C, more preferably 175 degrees C, and even more preferably at least up to about 200 degrees C. This material may include, but not limited to ; polyester, nylon, polyethylene terephthalate (PET), rayon, regenerated cellulose, or combinations and/or blends thereof. Preferably, the core material is polyethylene terephthalate (PET).

In one embodiment, the sheath is comprised of polypropylene (PP) and the core is composed of polyethylene terephthalate (PET), and the weight ratio of sheath to core is about 1 to 1. The fibrous web has a basis weight of 25 to 400 grams per square meter (gsm), more preferably about 60 to 250 gsm.

In another embodiment, the sheath is at least about 25% to 75%. more preferably at least about 40% to about 50%, polypropylene (PP), and the core is at least about 25% to 75%. more preferably at least about 40% to about 50% polyethylene terephthalate (PET).

In an alternative embodiment of the present invention, the sheath comprises about 10% to about30%, more preferably about 15% to about 20%, of the fiber weight. The sheath is a blend of at least about 25% to 75%, more preferably at least about 40% to about 50%, polypropylene (PP), and at least about 25% to 75%, more preferably at least about 40% to about 50%, poly 4- methylpentene (PMP). The core comprises about 70% to about 90%, more preferably about 80 to about 85%. of the fiber weight.

Preferably, the fiber has a size of about. 05 to 10 denier, more preferably about 1 to about 8 denier, even more preferably about 3 to about 5 denier. The cross-sectional shape of the bicomponent fiber used to construct a fibrous web may be round or any number of shapes that would increase the surface area, and thus enhance the oleophilic properties of the web. This would include, but not be limited to: round, trilobal, dog bone, rectangular, square, hexagonal, star shaped, or combinations thereof. In addition to the base shape of the cross section, there may be secondary appendages evident in the cross section of the fiber that serve to increase the surface area of the fiber.

Preferably, the fibrous web is nonwoven, although the web may be woven. The nonwoven bicomponent fibers may be assembled into the desired web structure by any of a number of techniques common in the art including, but not limited to ; carding, spunbond, air laying, wet laying, and composites or laminates thereof. Preferably, the web structure is assembled by carding.

The bicomponent fibers may then be formed into a web by any number of techniques common in the art including, but not limited to : entangling, felting, or other non-melt bonding techniques, or combinations thereof. Preferably, the bicomponent fibers are entangled, such that entangling is the predominant if not in fact the only web-forming method emploved. Such entangling may be achieved by either hydroentangling (spunlacing) or needling (felting). Melt- bonding or thermal bonding may be used, but if so. the degree of melt bonding should be limited so that the absorption properties of the web described herein are retained. Typically, in melt-bonded webs, the melted material of the fibers flows together into the interstitial void spaces to form bond sites, thereby reducing both the number and size of the interstitial void spaces between the fibers and the available free surface area on the fiber surfaces for attracting and holding grease. The size of the interstitial void spaces may be further reduced by fabric compaction in and adjacent to bond sites during calendar roll thermal bonding. This reduction of interstitial void spaces is magnified by increased fabric weight.

Typically, if a fibrous web, constructed of thermally (or melt) bonded bicomponent fibers, is subjected to temperatures higher than the melt temperature of the lowest melting component, the fibrous web would disintegrate because the bonds would release. High temperatures are most destructive for a fibrous web formed with sheath-core bicomponent fibers where the high melting component provides little or no bonding properties. Surprisingly, a fibrous web comprised of sheath-core bicomponent fibers and entangled according to the instant invention may withstand temperatures higher than the melting point of the lower melt temperature sheath because: 1) the integrity of the fibrous web is provided predominately by the entanglement of the fibers ; and 2) the high melt temperature core of the fiber helps to maintain web integrity.

Entangling, such as by hydroentangling or needling, joins the fibers into a coherent structure which has structural integrity yet maintains sufficient interstitial void space and free fiber surface area. The fibers are preferably entangled in the direction that is normal to the plane of the web to maximize void space. Preferably, the absorbent capacity is at least about 0.15 grams of grease per square cm of web at 120 degrees C, as measured by the absorbency test described below. Entangling allows the absorbent capacity of the fibrous web to be greater than the weight of the dry web, and more preferably at least two (2) times its weight, and even more preferably at least five (5) times its weight at 175 degrees C. The more preferred basis weight will be a function of end use requirement and entanglement process but will generally be about 20 to 600 grams per square meter (gsm). Typically, lighter weight matrices, about 20 grams per square meter to about 200 grams per square meter, are formed by hydroentangling or spunlacing. Typically, needling is used to form heavier basis weight fabrics, such as, but not limited to, fabrics with about 80 grams per square meter to about 600 grams per square meter. Needling can also be used to consolidate multiple layers have a combined basis weight of about 80 grams per square meter to about 600 grams per square meter. Layers could be similar or different in composition from each other, depending on end use.

The fibrous web may be a single layer of material or may be constructed of multiple layers superposed upon one another. If the fibrous web is composed of multiple layers, the layers may be bonded together by heat sealing, needling, or any number of means known in the art. Preferably, multiple layers of the fibrous web are bonded together by heat sealing. The heat sealing of multiple layers of the fibrous web can be in any number of patterns and continuous or discontinuous. The heat sealing process must involve sufficient heat and pressure to at least partially melt the high temperature fiber component to ensure a heat resistant bond. Additionally, the bonding area should be the minimum necessary to achieve bonding and/or sealing of the multiple layers together so as to maintain maximum void space. The fibrous web may also include a line of weakness. including, but not limited to, a line of perforations, laser scores, or tear-initiating notches, which would facilitate the use of a portion or part of the fibrous web. Preferably, the line of weakness is located along a heat seal of the fibrous web to facilitate separation along the line of weakness.

The fibrous web of the instant invention can be of various sizes and shapes. For example, the size of the fibrous web may be designed to absorb a specific amount of grease. Preferably, the web has a sheet with planar dimensions such that the surface area of one side of the sheet is about 200 to about 600 square cm, more preferably about 300 to 500 square cm, even more preferably 340 to 380 square cm. Additionally, the shape of the fibrous web may resemble a food product, such as, but not limited to, a bay leaf or a clove of garlic, or the size and shape may approximate that of the intending cooking container.

In use, the fibrous web of the instant invention is used to remove grease during and after the preparation of food. Foods, particularly ground meats, contain large amounts of aqueous liquids and grease. An absorbent fibrous web of the instant invention is placed adjacent to food during the cooking of the food, such as, but not limited to, in a frying pan or on top of soups and chilies. During cooking, the absorbent fibrous web preferentially absorbs the grease. After the food is cooked, the absorbent fibrous web is removed and discarded. Also, an absorbent fibrous web of the instant invention may be used to blot excess grease off of foods such as, but not limited to, pizza, bacon or hamburgers.

As previouslv discussed, the present invention provides a fibrous web for absorbing grease that is highly absorbent, maintains web integrity upon both exposure to high temperatures and saturation, and has little or no linting, sticking, pilling or shredding from contacting food. Also, the fibrous web may keep foods warm longer due to the insulation effects of the web. Accordingly, the present invention provides improved methods for removing grease prior to, during and subsequent to cooking or preparing food. In general, the method comprises placing the web in oil communication with food. Preparation of food includes, but is not limited to, manipulating, mixing, cooking, heating, or otherwise treating or modifying or handling food. By"oil communication", what is meant is the article is positioned to absorb grease from food before, during or subsequent to preparation. Oil communication can be provided but is not necessarily limited to the following categories: 1) the web is placed in admixture with or in food ; 2) the web is placed in direct contact with the surface of food or a part thereof ; 3) the web is positioned to come into contact with grease during preparation of food, but is not necessarily in direct contact with the food.

First, the fibrous web according to the present invention may be admixed with food. For example, the fibrous web may be stirred or swirled around or through the food or the food may be stirred around the web. This method ensures that the web contacts the surface area of the food for maximum absorption. This method is especially useful to absorb grease during cooking of foods such as, but not limited to, ground beef.

Second, the fibrous web may be used in contact with food. Because of the web integrity of the fibrous web of the instant invention. the fibrous web has little or no linting, sticking, pilling or shredding. For example, one method is to contact foods with the web. The foods may be either solids (such as, but not limited to, pizza) or liquids (such as, but not limited to, soups and stews).

"Contacting"may include, but is not limited to, padding, blotting, dragging over, or wrapping, etc.

Another method is to wrap the food in the fibrous web and squeeze the food slightly to contact even more surface. Another method is to use the fibrous web as a hot pad to transport foods. Because the fibrous web of the instant invention preferably consists of a relatively thick material, the fibrous web may act as a hot pad and at the same time absorbing the grease from the food's surface. For example, the fibrous web can be used to move foods such as, but not limited to, meats or roasts from a baking pan to serving platter. Another method of using the fibrous web includes covering food with the web to keep foods warm longer due the insulation effects of the web while removing surface grease at the same time. Another use for the fibrous web includes wrapping food, such as, but not limited to, leftovers, with the fibrous web to remove grease during storage. Another use includes placing food on top of the fibrous web and allowing the grease to absorb into the web while allowing fluids such as, but not limited to. water or other aqueous liquids to pass through the interstitial voids of the web, similar to a draining device having a surface with apertures or other means for allowing fluids to drain, such as, but not limited to, a colander. Additionally, the fibrous web may be placed adjacent to such a draining device, such as, but not limited to a colander, and then food may be placed on top of the web, thereby allowing fluids such as, but not limited to, water or other aqueous liquids to pass through the web and the draining device. Furthermore, the fluids that pass through the web in this manner, with or without the use of a draining device, may be collected and used for foods, such as, but not limited to, making flavorful low fat gravies and sauces.

Third, the fibrous web may be used in a manner such that it is in oil communication with the grease of the food but not in contact with the food. For example, the cooking container may be tipped to one side so that the grease collects on that one side. Then, the fibrous web may be placed on that side of the pan for absorption. It is also beneficial, but not required, to use a utensil to keep the food in a position other than the one side of the pan that is collecting the grease during tipping of the pan. Another example includes using the fibrous web of the instant invention as a"spatter shield"to prevent splattering from the cooking pan onto a stovetop, microwave, or other surrounding areas. While other absorbent articles in the prior art may melt from contact with a cooking pan at high temperatures, the fibrous web of the instant invention may be placed above the food being prepared and even in contact with the cooking container during cooking. When used in this manner, the fibrous web may wholly or partially cover the cooking container to stop the grease from splattering outside the container. This eliminates the messy cleanup of the surrounding area.

Another example includes using the fibrous web of the instant invention to absorb the residual grease left in a cooking container after cooking by wiping or cleaning the pan with the fibrous web.

This is especially effective when the cooking pan is still hot and the grease has not solidified.

As mentioned above, the fibrous web may also be used in a microwave. One method is to use the product as a cover or splatter shield (as described above) in the microwave. Another method includes wrapping the food in the fibrous web during cooking in the microwave. This allows steam to safely escape while capturing the spattering grease. The foods are then able to crisp in the microwave because the removal of the grease from the food by the fibrous web helps to prevent the food from becoming soggy.

Additionally, the present invention includes a system comprising the fibrous web and information that will inform the consumer, by written or spoken words and/or by pictures, that use of the fibrous web will absorb grease. Accordingly. the use of packages in association with information that will inform the consumer, by words and/or by pictures, that use of the fibrous web will provide benefits such as, but not limited to, improved absorption of grease is important. The information can include, e. g., advertising in all of the usual media, as well as statements and icons on the pacage, or on the fibrous web itself, to inform the consumer of the unique grease removal capabilities. The information may be communicated only bv verbal means, only by written means, only by pictorial means, or any combination thereof. Information can be provided in a form of written instructions placed on or in packaging for the fibrous web, on the fibrous web itself, or on a separate article (such as, but not limited to, a piece of paper) packaged with the fibrous web.

Obviously, the information need not be included directly with the product to constitute a svstem within this aspect of the invention. That is, for example, if a fibrous web is sold and advertisements are communicated generally about the fibrous web, this would constitute a system of this invention.

Generally, fibrous structures by their very nature lint. Moreover, fibrous structures that have a high absorbency usually have a high void volume. The high void volume typically exists because the individual fibers are not tightly bonded together. Consequently, fibrous structures with high absorbency may have an even greater loss of fibers or linting. Linting is undesirable, especially when the fibrous structures are used for food applications. The lint may remain in contact with the food, which gives the food an unsatisfactory appearance and also could potentially be ingested with the food.

Preferably, a fibrous web has both low linting and high absorbency. The fibrous web of the present invention preferably has a cumulative lint test value of less than 30 and absorbs at least about 8 times its weight in grease at 120 degrees C, according to the test described below.

Preferably, the web is sized such that 8 times its weight at 120 degrees C is about 40 to about 100 grams of grease, more preferably at least about 55 grams to 75 grams of grease.

The cumulative lint test value is determined by the sum of the quantity of linting of the fibrous web using three separate tests. The first test comprises using a 1-inch segment of a cut edge of the fibrous web. The quantity of free fiber ends that protrude more than 250 microns from the edge of the web is counted. The edge from which the fiber protrusion is measured is located where the web's density changes such that the individual fibers begin to become identifiable. A jeweler's loop or other suitable low magnification implement may be used. The second test comprises folding the fibrous web and marking off a 1-inch segment along the fold. Again, the quantity of free fiber ends that protrude more than 250 microns from the folded edge of the web is counted. The third test comprises using a 1 inch long piece of adhesive tape. The adhesive tape is SCOTCH MAGIC TAPE (t, manufactured by the Minnesota Manufacturing and Mining Company, located in St. Paul, Minnesota. The steps include weighing the tape, pressing the tape firmly onto the surface of the web, peeling it off the web, and weighing the tape with adhesively attached fibers. The difference between the weight of the tape and fibers and the tape alone is recorded. The cumulative lint test value is the algebraic sum of the fiber count from the first two tests added to the results of the third test, which are in units of milligrams per square inch.

Preferably, the cumulative lint test value is less than 30. more preferably less than 25, and even more preferably less than 22.

The first two tests primarily address the issue of perceived linting. If too many fibers are protruding from the surface of the web, the user perceives that the web may lint fibers into the food. The third test is an approximate measure of how many fibers are removed by simulating forces that may be exerted on the web when it is used. Preferably, the amount of actual linting is less than about 10 milligrams per square inch of web, more preferably less than 7 milligrams per square inch of web, and even more preferably less than 5 milligrams per square inch of web.

The absorbency value of the fibrous web was calculated by the absorption test as follows.

First, approximately 48 ounces of CRISCOG vegetable oil, UPC 37000-00482, manufactured by the Procter & Gamble Company of Cincinnati. Ohio. is placed into a PRYEX@ flat bottom glass bowl having dimensions of 190 inches by 100 inches, Part No. 3140, manufactured by CORNING.

INC@, which is located in Coming NY. A spin bar is placed in the bowl containing vegetable oil.

The bowl is then placed on a stirrer/hot plate. The stirrer/hot plate is Model PC 620, with 1113 watts of power, and is manufactured by CORNING, INCAS), which is located in Corning, NY. The bowl is heated so that the oil is 120 degrees C. The temperature 120 degrees C is utilized because this is the typical temperature utilized to cook foods in a frying pan. A six-inch by six-inch square of the fibrous web is weighed such that the accuracy is plus or minus 0.01 gram. Then, the fibrous web is placed in the oil for 30 seconds. Afterwards, the fibrous web is removed from the bowl and placed flat onto a metal drain screen having grid spacing of one half to three quarters an inch. The web is allowed to drain horizontally on the screen for 15 seconds. The fibrous web with oil is then reweighed. The difference between the weight of the dry fibrous web and the fibrous web with the oils is then calculated to be the amount of grease absorption. The absorbency value is determined as the grease absorption per amount of fibrous web bv weight. Preferably, the absorbency value at 120 degrees C is at least about 8 times the weight of the dry fibrous web.

Typically, the more absorbent a fibrous web is, the more likely it lints. Thus, it is desirable to have a fibrous matrix that has a high absorbency and low linting. The ratio of the cumulative lint test value to the absorbency value at 120 degrees C may also be determined. Preferably, the ratio of the cumulative lint test value to absorbency value at 120 degrees C is less than 3, more preferably, the ratio is less than 2.5, and most preferably the ratio is less than 2.

Generally, fibrous structures known in the art, such as, but not limited to, paper towels, absorb both grease and aqueous based liquids. However, most of the flavor and taste of the foods is contained in the aqueous based liquids. Thus, it is desirable to have a fibrous web that preferentially absorbs grease over aqueous based liquids so that it removes the grease and leaves the taste. This is especially important in cooking situations such as, but not limited to, frying, baking and sauteing.

Many foods that are aqueous liquid based, such as, but not limited to, soups, stews, or chili, etc., are cooked at a temperature of about 65 degrees C. It is desired that the fibrous web absorb very little aqueous liquid when used to remove grease from aqueous based foods. Thus, 65 degrees C was chosen to be the temperature at which the aqueous liquid capacity would be measured. The water absorbency value of the fibrous web at these temperatures was calculated by the absorption test described above, except water was used instead of oil and the water was at 65 degrees C.

Moreover, it is desirable that the same fibrous web that can preferentially absorb grease over aqueous liquids from aqueous based foods at 65 degrees C also be able to absorb grease from food at the high temperatures encountered in a frying pan without any discernable distortion due to heat. At temperatures over 200 degrees C, grease begins to smoke. Thus, 200 degrees C was chosen to be the temperature at which the oil absorbency would be measured. The oil absorbency value of the fibrous web at these temperatures was calculated by the absorption test described above, except the oil was at 200 degrees C.

Preferably, the ratio of the oil absorbency value (weight of oil to weight of web) at about 200 degrees C to water absorbency value (weight of water to weight of web) at about 65 degrees C is at least about 2, more preferably the ratio is at least about 3, even more preferably the ratio is at least about 4, and most preferably the ratio is at least about 4.5.

FIG. 1 illustrates a cross-sectional view of an embodiment of a"sheath-core"bicomponent fiber and is designated generally as 10. The bicomponent fiber 10 is comprised of a sheath material 11 and a core material 12.

FIG. 2 shows an embodiment of a fibrous web 20.

FIG. 3 shows an embodiment where the fibrous web comprises multiple layers superposed upon one another. The multiple layers are heat sealed 31 together around the periphery and via one centrally located seal, and the fibrous web comprises perforations 32.

Although particular versions and embodiments of the present invention have been shown and described, various modifications can be made to this absorbent fibrous web without departing from the teachings of the present invention. The terms used in describing the invention are used in their descriptive sense and not as terms of limitation, it being intended that all equivalents thereof be included within the scope of the claims.