Embossed wiper and process for making same

Abstract

Wipers are disclosed formed from two, three, or more fibrous sheets. The fibrous sheets or plies are attached together by embossing a pattern into opposite sides of the product such that at least some of the embossments on one side align with at least some of the embossments on the opposite side. The resulting wiper includes outer layers primarily made from polymer synthetic fibers and a middle layer comprised primarily of cellulose fibers, such as cellulose pulp fibers. The wipers can be formed without any thermal bonding or ultrasonic bonding and can be formed without containing any polyester fibers. The wipers have demonstrated excellent oil absorbency.

Description

[0001] EMBOSSED WIPERAND PROCESS FOR MAKING SAME

[0002] CROSS REFERENCE TO RELATED APPLICATIONS

[0003] This application claims priority to the benefit of U.S. Provisional Application No. 63 / 739,726, filed December 30, 2024, which is expressly incorporated herein by reference in its entirety.

[0004] BACKGROUND

[0005] Domestic and industrial wipers are often used to pick up and absorb both polar liquids and non-polar liquids. The wipers should be constructed to have a sufficient absorption capacity to hold a liquid within the wiper structure In addition, the wipers should also possess good physical strength and abrasion resistance to withstand the tearing, stretching and abrading forces often applied during use.

[0006] Conventional wiping products have been made from woven and knitted fabrics. Such wipers have been used in all different types of industries, such as for industrial applications, food service applications, health and medical applications, and for general consumer use.

[0007] In the past, nonwoven wipers have been constructed made from pulp fibers alone or in combination with synthetic fibers. For example, in the past, spunbond webs made from continuous filaments have been hydroentangled with pulp fibers in order to produce a resilient wiping product. In many instances, these webs are for single use applications and then disposed. Although these wipers possess good levels of strength and absorbency, the wipers typically do not possess the same cleaning characteristics as woven and knitted fabrics, particularly when wiping up oil and grease.

[0008] In view of the above, a need currently exists for a disposable nonwoven wiper that has improved oil and grease cleaning efficacy. A need also exists for a disposable nonwoven wiper that is well suited to cleaning oil and grease spills at a relatively low basis weight, especially in comparison to woven and knitted cleaning cloths.

[0009] SUMMARY

[0010] In general, the present disclosure is directed to a cleaning product made from multiple plies of material that is particularly well suited for not only wiping up oils and greases but for absorbing and holding the oils and greases into the interior of the product. In accordance with the present disclosure, two or more sheets of material are brought together such that the resulting wiper includes outer layers made from polymer fibers and a middle layer made from cellulose fibers, such as wood pulp fibers. The different plies or sheets are attached together by embossing patterns into opposite sides of the sheet. The embossing patterns are applied to the multiple sheets such that embossments on one side of the sheet are in alignment with embossments on the opposite side of the sheet. The embossments, for instance, can penetrate into the middle layer containing the cellulose fibers. The embossmentscause the sheets to bond together through fiber entanglement which produces a structure that is particularly well suited for absorbing oils, water, and other liquids.

[0011] In one embodiment, for instance, the present disclosure is directed to a wiper comprising at least a first sheet attached to a second sheet by embossments. The wiper includes a first outer surface opposite a second outer surface. The wiper is comprised of at least three layers. The three layers include a first outer nonwoven layer comprised of polymer synthetic fibers, a second outer nonwoven layer comprised of polymer synthetic fibers, and a middle layer positioned between the first nonwoven outer layer and the second nonwoven outer layer. The middle layer comprises cellulose fibers and, in one aspect, is free of polymer synthetic fibers. The cellulose fibers, for instance, can comprise pulp fibers such as wood pulp fibers, non-wood pulp fibers, or mixtures thereof.

[0012] The embossments that are used to attach the sheets together include a first pattern of embossments extending into the first outer surface and a second pattern of embossments extending into the second outer surface. At least a portion of the embossments of the first pattern align with at least a portion of the embossments of the second pattern. For instance, the embossments can be in alignment in the Z-direction of the wiper. The embossments can extend into the middle layer of the wiper and cause the sheets to attach together with sufficient strength to prevent delamination when in use. The embossments extending into the first outer surface and the embossments extending into the second outer surface can comprise discrete shapes. In one embodiment, the embossments are formed by feeding the multiple sheets through a nip formed between a first embossing roller and a second embossing roller. Each of the embossing rollers can include a pattern of embossing elements that are in alignment with each other as the wiper is embossed.

[0013] In one embodiment, the wiper is a two-ply product made from the first sheet and the second sheet. In one aspect, the first sheet can comprise a spunbond web and the second sheet can comprise a hydroentangled web. The hydroentangled web can comprise a nonwoven web comprised of polymer synthetic fibers hydroentangled with cellulose fibers. The first sheet and the second sheet are brought together such that the cellulose fibers form the middle layer within the wiper.

[0014] Alternatively, the first sheet can comprise a hydroentangled web as described above and the second sheet can also comprise a hydroentangled sheet as described above. The two hydroentangled webs can be brought together such that cellulose fibers from the first hydroentangled web combine and mix with cellulose fibers from the second hydroentangled web for forming the middle layer.

[0015] In an alternative embodiment, the wiper can be formed from a first sheet, a second sheet, and a third sheet. The first sheet and the second sheet can comprise spunbond webs. The third sheet can comprise a tissue web that is positioned between the first sheet and the second sheet. The tissueweb, for instance, can comprise an uncreped through-air dried web or a creped web.

[0016] In the different embodiments described above, the first outer layer can comprise a spunbond web and the second outer layer can comprise a spunbond web. The spunbond webs can be made from polypropylene fibers. In one aspect, for instance, the wiper is free of polyester fibers. The outer spunbond webs, in one aspect, can have a basis weight of from about 6 gsm to about 28 gsm, such as from about 8 gsm to about 21 gsm. The cellulose fibers contained in the middle layer can have a basis weight of from about 12 gsm to about 120 gsm, such as from about 25 gsm to about 90 gsm.

[0017] The wiper of the present disclosure can generally have a basis weight of from about 35 gsm to about 200 gsm, such as from about 40 gsm to about 130 gsm. The wiper can have a caliper of greater than about 0.4 mm, such as greater than about 0.5 mm, such as greater than about 0.6 mm, such as greater than about 0.7 mm, and less than about 2 mm. The wiper can display a void volume when tested at 0.3 psi of greater than about 60%, such as greater than about 70%, such as greater than about 75%.

[0018] The wiper can display an oil absorbency of greater than about 4.5 grams of oil per gram of wiper, such as greater than about 5 grams of oil per gram of wiper, such as greater than about 5.5 grams of oil per gram of wiper, such as greater than about 6 grams of oil per gram of wiper, and less than about 20 grams of oil per gram of wiper. The wiper can display a water absorbency of greater than about 3.5 grams of water per gram of wiper, such as greater than about 4 grams of water per gram of wiper, such as greater than about 4.2 grams of water per gram of wiper.

[0019] In one embodiment, the embossments formed into the outer layers of the wiper are used to attach the different plies together without using an adhesive. In one aspect, the plies or sheets can be held together without forming any thermal bonds or ultrasonic bonds within the wiper. As described above, embossments formed into one side of the wiper align with embossments on the opposite side of the wiper. For example, greater than 50% of the embossments, such as greater than about 80% of the embossments, such as greater than about 90% of the embossments of the first pattern formed into the first outer layer can align with embossments formed into the opposite second outer layer. In general, any suitable pattern of embossments can be formed into the wiper. The first pattern of embossments and / or the second pattern of embossments, for instance, can occupy greater than about 3% of the surface area of the outer surface of the wiper, such as greater than about 5% of the surface area, such as greater than about 8% of the surface area, such as greater than about 10% of the surface area, such as greater than about 15% of the surface area, such as greater than about 20% of the surface area, such as greater than about 25% of the surface area, such as greater than about 30% of the surface area, such as greater than about 35% of the surface area, such as greater than about 40% of the surface area of the wiper. The embossing patterns can occupy generally less than about80% of the surface area of the outer surface, such as less than about 70% of the surface area of the outer surface, such as less than about 50% of the surface area of the outer surface. In one embodiment, the first pattern of embossments is identical to the second pattern of embossments and both embossing patterns are in alignment in the Z-direction of the wiper.

[0020] Other features and aspects of the present disclosure are discussed in greater detail below.

[0021] BRIEF DESCRIPTION OF THE DRAWINGS

[0022] A full and enabling disclosure of the present disclosure is set forth more particularly in the remainder of the specification, including reference to the accompanying figures, in which:

[0023] Figure 1 is a cross-sectional view of one embodiment of a wiper made in accordance with the present disclosure;

[0024] Figure 2 is a cross-sectional view of one embodiment of a two-ply substrate that can be used to produce the wiper illustrated in Figure 1;

[0025] Figure 3 is a cross-sectional view of another embodiment of a two-ply substrate that can be used to produce the wiper illustrated in Figure 1 ;

[0026] Figure 4 is a cross-sectional view of another embodiment of a three-ply substrate that can be used to produce the wiper illustrated in Figure 1 ;

[0027] Figure 5 is a side view of one embodiment of an embossing process that can be used in accordance with the present disclosure;

[0028] Figure 6 is a side view of another embodiment of an embossing process that may be used in accordance with the present disclosure;

[0029] Figure 7 is a graphical representation of some of the results obtained in the example below; and

[0030] Figure 8 is a graphical representation of some of the results obtained in the example below. Repeat use of reference characters in the present specification and drawings is intended to represent the same or analogous features or elements of the present invention.

[0031] DEFINITIONS

[0032] As used herein the term "nonwoven web” generally refers to a web having a structure of individual fibers or threads which are interlaid, but not in an identifiable manner as in a knitted fabric. Examples of suitable nonwoven fabrics or webs include, but are not limited to, meltblown webs, spunbond webs, bonded carded webs, airlaid webs, coform webs, hydraulically entangled webs, and so forth.

[0033] As used herein, the term “meltblown web” generally refers to a nonwoven web that is formed by a process in which a molten thermoplastic material is extruded through a plurality of fine, usually circular, die capillaries as molten fibers into converging high velocity gas (e.g. air) streams thatattenuate the fibers of molten thermoplastic material to reduce their diameter, which may be to microfiber diameter. Thereafter, the meltblown fibers are carried by the high velocity gas stream and are deposited on a collecting surface to form a web of randomly dispersed meltblown fibers. Such a process is disclosed, for example, in U.S. Pat. No. 3,849,241 to Butin, et al., which is incorporated herein in its entirety by reference thereto for all purposes. Generally speaking, meltblown fibers may be microfibers that are substantially continuous or discontinuous, generally smaller than 10 microns in diameter, and generally tacky when deposited onto a collecting surface.

[0034] As used herein, the term “spunbond web” generally refers to a web containing small diameter substantially continuous fibers. The fibers are formed by extruding a molten thermoplastic material from a plurality of fine, usually circular, capillaries of a spinnerette with the diameter of the extruded fibers then being rapidly reduced as by, for example, eductive drawing and / or other well-known spunbonding mechanisms. The production of spunbond webs is described and illustrated, for example, in U.S. Patent Nos. 4,340,563 to Appel, et al„ 3,692,618 to Dorschner, et al., 3,802,817 to Matsuki, et al., 3,338,992 to Kinney, 3,341,394 to Kinney, 3,502,763 to Hartman, 3,502,538 to Levy, 3,542,615 to Dobo, et al., and 5,382,400 to Pike, et al., which are incorporated herein in their entirety by reference thereto for all purposes. Spunbond fibers are generally not tacky when they are deposited onto a collecting surface. Spunbond fibers may sometimes have diameters less than about 40 microns, and are often between about 5 to about 20 microns.

[0035] As used herein, the term "coform" means a non-woven composite material of air-formed matrix material comprising thermoplastic polymeric meltblown fibers such as, for example, microfibers having an average fiber diameter of less than about 10 microns, and a multiplicity of individualized absorbent fibers such as, for example, wood pulp fibers disposed throughout the matrix of polymer microfibers and engaging at least some of the microfibers to space the microfibers apart from each other. The absorbent fibers are interconnected by and held captive within the matrix of microfibers by mechanical entanglement of the microfibers with the absorbent fibers, the mechanical entanglement and interconnection of the microfibers and absorbent fibers alone forming a coherent integrated fibrous structure. These materials are prepared according to the descriptions in U.S. Pat. No. 4,100,324 to Anderson et al. U.S. Pat. No. 5,508,102 to Georger et al. and U.S. Pat. No. 5,385,775 to Wright.

[0036] As used herein, the terms “machine direction” or “MD” generally refers to the direction in which a material is produced. The term “cross-machine direction” or “CD” refers to the direction perpendicular to the machine direction.

[0037] As used herein "dry" means that the substrate contains less than about 10 percent water as tested under ASTM D1744-92 entitled "Standard Test Method for Determination of Water in Liquid Petroleum Products by Karl Fischer Reagent" modified as follows: A 500 milligram + 100 milligramsample is cut from the substrate and weighed on an analytical balance to the nearest 0.1 milligram. Adjust the size of the sample as needed to obtain the specified sample weight. Introduce the sample to the titration vessel and stir approximately 5 minutes to extract the water from the sample. After stirring the sample, titrate as described in the above test procedure and calculate the percent water as described in the above test procedure.

[0038] As used herein, oil absorbent capacity is measured for each wipe using the Absorbent Capacity testing protocol from IPS Testing. A container is filled with at least 50 mm of motor oil in order to submerge a 4"x4” piece of a sample wiper. The 4”x4” piece is weighed, and the value is recorded as dry weight of the piece Each wiper piece is submerged in motor oil for 3 minutes, removed from the testing fluid using prongs, and hung in a diamond-shape such that one corner of the piece is lower than the other corners of the piece. The piece is allowed to dry for 5 minutes. The weight of each wet piece is recorded as the wet weight. Each sample wiper is tested 3 separate times. Absorbent capacity (g / 4”x4") is calculated by subtracting the wet weight from the dry weight. Specific capacity (g / g) is calculated by dividing absorbent capacity by the dry weight of the material. Percent absorption is calculated by multiplying the specific capacity by 100%.

[0039] As used herein, water absorbent capacity is measured according to the same test as oil absorbent capacity only using deionized water instead of motor oil.

[0040] The term "cellulose fibers" as used herein refers to fibers from natural sources such as woody and non-woody plants. Woody plants include, for example, deciduous and coniferous trees. Non-woody plants include, for example, cotton, flax, esparto grass, milkweed, straw, jute, hemp, and bagasse. "Pulp fibers’’ refers to delignified cellulose fibers and can include hardwood fibers, softwood fibers, and mixtures thereof.

[0041] As used herein the term “caliper” is the representative thickness of a single sheet (caliper of tissue products comprising two or more plies is the thickness of a single sheet of tissue product comprising all plies) measured in accordance with TAPPI test method T402 using an EMVECO 200-A Microgage automated micrometer (EMVECO, Inc., Newberg, Oreg.). The micrometer has an anvil diameter of 2.22 inches (56.4 mm) and an anvil pressure of 132 grams per square inch (per 6.45 square centimeters) (2.0 kPa).

[0042] As used herein the term “sheet bulk” refers to the quotient of the caliper (generally having units of pm) divided by the bone dry basis weight (generally having units of gsm).

[0043] As used herein, “void volume” is the amount of space inside the nonwoven material not taken up by solid material, such as fibers. In one aspect, void volume per surface area can be determined. Void volume can be determined at an applied pressure, such as at a pressure of 0.05 psi or 0.3 psi.

[0044] As used herein the term “pattern” generally refers to the arrangement of one or more designelements. Within a given pattern the design elements may be the same or may be different, further the design elements may be the same relative size or may be different sizes. For example, in one embodiment, a single design element may be repeated in a pattern, but the size of the design element may be different from one design element to the next within the pattern.

[0045] As used herein the term “dot embossment" or “dot emboss element” means an embossment or an embossing element that exhibits an aspect ratio of about 1 :1.25 or less, such as an aspect ratio from about 1.0 to about 1.25. Non-limiting examples of dot embossments are embossments having a circular, oval, square, or triangular cross-sectional shape.

[0046] As used herein, “tensile testing” was done in accordance with TAPPI test method T-576 “Tensile properties of towel and tissue products (using constant rate of elongation)” wherein the testing is conducted on a tensile testing machine maintaining a constant rate of elongation and the width of each specimen tested is 3 inches. More specifically, samples for dry tensile strength testing were prepared by cutting a 3 ± 0.05 inch (76.2 ± 1.3 mm) wide strip in either the machine direction (MD) or cross-machine direction (CD) orientation using a JDC Precision Sample Cutter (Thwing-Albert Instrument Company, Philadelphia, PA, Model No. JDC 3-10, Serial No. 37333) or equivalent. The instrument used for measuring tensile strengths was an MTS Systems Sintech 11 S, Serial No. 6233. The data acquisition software was an MTS TestWorks® for Windows Ver. 3.10 (MTS Systems Corp., Research Triangle Park, NC). The load cell was selected from either a 50 Newton or 100 Newton maximum, depending on the strength of the sample being tested, such that the majority of peak load values fall between 10 to 90 percent of the load cell's full scale value. The gauge length between jaws was 4 ± 0.04 inches (101.6 ± 1 mm) for facial tissue and towels and 2 ± 0.02 inches (50.8 ± 0.5 mm) for bath tissue. The crosshead speed was 10 ± 0.4 inches / min (254 ± 1 mm / min), and the break sensitivity was set at 65 percent. The sample was placed in the jaws of the instrument, centered both vertically and horizontally. The test was then started and ended when the specimen broke. The peak load was recorded as either the "MD tensile strength" or the "CD tensile strength" of the specimen depending on direction of the sample being tested. Ten representative specimens were tested for each product or sheet and the arithmetic average of all individual specimen tests was recorded as the appropriate MD or CD tensile strength of the productor sheet in units of grams of feree per 3 inches of sample. The geometric mean tensile (GMT) strength was calculated and is expressed as grams-force per 3 inches of sample width. Tensile energy absorbed (TEA) and slope are also calculated by the tensile tester. TEA is reported in units of gn cm / cm2. Slope is recorded in units of kg. Both TEA and Slope are directionally dependent and thus MD and CD directions are measured independently. Geometric mean TEA and geometric mean slope are defined as the square root of the product of the representative MD and CD values for the given property.DETAILED DESCRIPTION

[0047] It is to be understood by one of ordinary skill in the art that the present discussion is a description of exemplary embodiments only and is not intended as limiting the broader aspects of the present disclosure.

[0048] In general, the present disclosure is directed to a wiping product well suited to wiping away and absorbing all different types of liquids. The wiping product is particularly well suited for quickly absorbing oils and retaining the oils within the interior of the product. The oils can include, for instance, petroleum oils, petroleum-based greases, silicone oils, other greases, vegetable-based oils and fats, animal-based oils and fats, and human skin oils such as face oils. The wiping product is also well suited for absorbing water or aqueous compositions and organic solvents.

[0049] In accordance with the present disclosure, the wiping product comprises at least two sheets or plies that are attached together through an embossing process. The resulting wiper includes distinct fibrous layers. For instance, the wiper can include outer layers made from synthetic fibers, such as polymer synthetic fibers. The outer layers, for instance, can be somewhat oleophilic for quickly absorbing oils. The wiper further includes at least one middle layer comprised primarily or exclusively of cellulose fibers. The cellulose fibers, for instance, can comprise cellulose pulp fibers. The middle cellulose layer is well suited for absorbing and retaining liquids and can have a different pore structure than the outer layers.

[0050] As described above, the wiper is produced by combining different sheets or plies together using a pattern of embossments. More particularly, the two or more sheets or plies are brought together and embossed on opposite surfaces by embossing elements to form embossments within each surface. In accordance with the present disclosure, the embossments are in alignment in the Z-direction (perpendicular to the surface) which cause fiber entanglement and the sheets or plies to attach together. In one aspect, the wiper is embossed without causing thermal bonding. Thermal bonding, for instance, can adversely affect the porosity of the wiper and inhibit flow of liquids into the interior of the product. Consequently, in one embodiment, the sheets or plies are attached together without causing thermal bonding, ultrasonic bonding, or the like, for producing a product with significant void volume and sufficient strength for use in wiping processes.

[0051] In addition to having excellent oil and water absorption properties, wipers made according to the present disclosure can offer various other advantages and benefits. For instance, once constructed, the wipers have a cloth-like feel. Thus, the wipers have characteristics and qualities that are consumer-preferred when using the wipers for cleaning. In addition, due to the multi-layer construction of the wiper, the wiper produces little to no lint. For instance, the cellulose fibers are maintained in a middle layer between synthetic polymer fiber layers that prevent the cellulose fibersfrom being emitted from the product.

[0052] Referring to FIG. 1, one embodiment of a wiper 12 made in accordance with the present disclosure is shown. As described above, the wiper 12 is constructed by attaching two or more plies or fibrous sheets together through an embossing process to form a multi-layer structure. As shown in FIG. 1, the wiper 12 includes a first outer nonwoven layer 14 that defines a first outer surface 18 and a second outer nonwoven layer 16 that defines a second outer surface 20. The wiper 12 further includes a middle layer 26 positioned between the first outer nonwoven layer 14 and the second outer nonwoven layer 16. During formation of the wiper 12, a first pattern of embossments 22 is formed into the first outer surface 18 and a second pattern of embossments 24 is formed into the second outer surface 20. As illustrated in FIG. 1, at least a portion or substantially all of the embossments 22 are in alignment with the embossments 24 in the Z-direction (perpendicular to the outer surfaces). The embossments 22 and 24, as shown in FIG. 1, can extend into the middle layer 26 and can compress and densify the wiper 12 at discrete locations. The embossments 22 and 24, for instance, can cause fiber entanglement and can cause the multiple plies to attach together and form a consolidated wiper product.

[0053] Various different fibrous sheets or substrates can be brought together and embossed for forming the wiper 12 as shown in FIG. 1. For instance, various different configurations are illustrated in FIGS. 2-4 in which the wiper 12 is formed. As shown in FIGS. 2-4, for instance, the wiper 12 can be made from two fibrous sheets or three fibrous sheets that are superimposed and embossed together.

[0054] In each embodiment, a multi-layer structure as shown in FIG. 1 is formed. For example, the wiper 12 includes a middle fibrous layer 26 that is positioned between two outer nonwoven layers 14 and 16.

[0055] In accordance with the present disclosure, the outer layers 14 and 16 contain synthetic fibers, such as polymer synthetic fibers. For example, the first outer nonwoven layer 14 and the second outer nonwoven layer 16 can contain synthetic polymer fibers in an amount greater than about 60% by weight, such as in an amount greater than about 80% by weight, such as in an amount greater than about 90% by weight, and, in one embodiment, are made exclusively from synthetic polymer fibers. The synthetic polymer fibers can comprise microfibers, staple fibers, or continuous filament fibers. The outer nonwoven layers 14 and 16, for instance, can comprise spunbond webs, meltblown webs, bonded carded webs, airlaid webs, coform webs, hydroentangled webs, and combinations thereof.

[0056] In one embodiment, at least one of the outer layers comprises a spunbond web. It has been discovered that spunbond webs can be produced that have a pore size capable of efficiently wiping up or adsorbing oily substances into the interior of the wiper. Thus, in one embodiment, at least one of the outer layers comprises a spunbond web. In one embodiment, the spunbond web that forms theouter layer can comprise a spunbond web that is part of a hydroentangled web in which a spunbond web has been hydroentangled with cellulose fibers

[0057] The outer layers can be made from various different polymers. Exemplary polymers for use in forming nonwoven web materials may include, for instance, polyolefins, e.g., polyethylene, polypropylene, polybutylene, etc.; polytetrafluoroethylene; polyesters, e.g., polyethylene terephthalate and so forth; polyvinyl acetate; polyvinyl chloride acetate; polyvinyl butyral; acrylic resins, e.g., polyacrylate, polymethylacrylate, polymethylmethacrylate, and so forth; polyamides, e.g., nylon; polyvinyl chloride; polyvinylidene chloride; polystyrene; polyvinyl alcohol; polyurethanes; polylactic acid; copolymers thereof; and so forth. Synthetic cellulosic polymers may also be used, including but not limited to, cellulosic esters; cellulosic ethers; cellulosic nitrates; cellulosic acetates; cellulosic acetate butyrates; ethyl cellulose; regenerated celluloses, such as viscose, rayon, and so forth. It should be noted that the polymer(s) may also contain other additives, such as processing aids or treatment compositions to impart desired properties to the fibers, residual amounts of solvents, pigments or colorants, and so forth. In one aspect, the outer layers comprise polypropylene fibers and the product can be constructed without containing more expensive polyester fibers.

[0058] Monocomponent and / or multicomponent fibers may be used to form the outer layers.

[0059] Monocomponent fibers are generally formed from a polymer or blend of polymers extruded from a single extruder. Multicomponent fibers are generally formed from two or more polymers (e.g., bicomponent fibers) extruded from separate extruders. The polymers may be arranged in substantially constantly positioned distinct zones across the cross-section of the fibers. The components may be arranged in any desired configuration, such as sheath-core, side-by-side, pie, island-in-the-sea, three island, bull's eye, or various other arrangements known in the art and so forth.

[0060] Although any combination of polymers may be used, the polymers of the multicomponent fibers are typically made from thermoplastic materials with different glass transition or melting temperatures where a first component (e.g., sheath) melts at a temperature lower than a second component (e.g., core). Softening or melting of the first polymer component of the multicomponent fiber allows the multicomponent fibers to form a tacky skeletal structure, which upon cooling, stabilizes the fibrous structure. For example, the multicomponent fibers may have from about 20% to about 80%, and in some embodiments, from about 40% to about 60% by weight of the low melting polymer. Further, the multicomponent fibers may have from about 80% to about 20%, and in some embodiments, from about 60% to about 40%, by weight of the high melting polymer.

[0061] A nonwoven web material may also contain an additional fibrous component such that it is considered a composite. For example, a nonwoven web may be entangled with another fibrous component using any of a variety of entanglement techniques known in the art (e.g., hydraulic, air,mechanical, etc.). In one embodiment, as described above, the nonwoven web is entangled with cellulosic fibers using hydraulic entanglement. A typical hydraulic entangling process utilizes high pressure jet streams of water to entangle fibers to form a highly entangled consolidated fibrous structure, e.g., a nonwoven web. The hydroentangled web may contain pulp fibers in an amount less than about 90% by weight, such as less than about 85% by weight, such as in an amount less than about 80% by weight, such as in an amount less than about 70% by weight, such as less than about 60% by weight, such as less than about 50% by weight, such as less than about 40% by weight. The pulp fibers are generally present in the hydroentangled web in an amount greater than about 30% by weight, such as greater than about 40% by weight, such as greater than about 50% by weight, such as greater than about 60% by weight, such as greater than about 70% by weight.

[0062] The basis weight of the nonwoven web material may generally vary, such as from about 5 grams per square meter (“gsm”) to 45 gsm, in some embodiments from about 7 gsm to about 25 gsm, and in some embodiments, from about 8 gsm to about 15 gsm. When multiple nonwoven web materials, such materials may have the same or different basis weights.

[0063] The size of the fibers used to construct the outer layers can vary depending upon various factors. When the outer layer is used to wipe up oily spills or adsorb oily substances, in one embodiment, fibers can be used that have a relatively large size. Alternately, fibers can be used that have a relatively small to medium size. For instance, the fibers can have a denier of greater than about 0.1, such as greater than about 0.25, such as greater than about 0.5, such as greater than about 0.75, such as greater than about 1.0, such as greater than about 1.25, such as greater than about 1.5, such as greater than about 2.0, such as greater than about 2.2, such as greater than about 2.5, such as greater than about 2.7, such as greater than about 3. The denier of the fibers is generally less than about 8, such as less than about 6.

[0064] The middle layer 26 of the wiper 12 contains cellulose fibers. The cellulose fibers can be contained in the middle layer 26 in an amount greater than about 50% by weight, such as in an amount greater than about 60% by weight, such as in an amount greater than about 70% by weight, such as in an amount greater than about 80% by weight, such as in an amount greater than about 90% by weight. In one embodiment, the middle layer 12 can be comprised entirely of cellulose fibers (except where the cellulose fibers are entangled with the polymer synthetic fibers of the outer layers). For instance, in one embodiment, the middle layer 26 does not include any polymer synthetic fibers that extend through the layer or are homogenously mixed with the cellulose fibers. It was discovered, for instance, that the wiper 12 can have better liquid retention properties when the middle layer does not contain polymer synthetic fibers. The embossments 22 and 24 can also create a consolidated wiper without having to form thermal or ultrasonic bonds within the middle layer 26. Consequently, there arevarious advantages and benefits to creating a middle layer 26 that only contains cellulose fibers. Cellulosic fibers that may be incorporated into the material include but not limited to nonwoody fibers (including bast fibers), such as cotton, abaca, kenaf, sabai grass, flax, esparto grass, straw, jute hemp, bagasse, milkweed floss fibers, and pineapple leaf fibers; and woody or pulp fibers such as those obtained from deciduous and coniferous trees, including softwood fibers, such as northern and southern softwood kraft fibers; hardwood fibers, such as eucalyptus, maple, birch, and aspen. Pulp fibers can be prepared in high-yield or low-yield forms and can be pulped in any known method, including kraft, sulfite, high-yield pulping methods and other known pulping methods. In one aspect, crosslinked cellulose or pulp fibers can be used. Fibers prepared from organosolv pulping methods can also be used. The cellulosic pulp fibers described above, for instance, can have an average fiber length of less than about 8 mm, such as less than about 6 mm, such as less than about 4 mm. The average fiber length of the cellulosic pulp fibers is generally greater than about 1 mm, such as greater than about 2 mm, such as greater than about 3 mm.

[0065] Other cellulosic fibers that can be incorporated into the material include any suitable regenerated cellulose fibers including rayon fibers, viscose fibers, model fibers, lyocell fibers, and the like. The regenerated cellulose fibers, cotton fibers, and various other bast fibers can generally have longer fiber lengths than pulp fibers. For instance, the fibers can comprise staple fibers and can have a fiber length of from about 8 mm to about 70 mm. The fiber length, for instance, can be greater than about 10 mm, such as greater than about 12 mm, such as greater than about 14 mm, and generally less than about 60 mm, such as less than about 50 mm, such as less than about 40 mm, such as less than about 30 mm.

[0066] Referring to FIGS. 2-4, three different embodiments are shown of substrates or fibrous sheets that can be embossed together in accordance with the present disclosure for forming the wiper 12 as shown in FIG. 1. In FIGS. 2 and 3, for instance, the wiper 12 is made from two fibrous sheets or plies. In FIG. 4, however, the wiper 12 is made from three fibrous sheets or plies.

[0067] Referring to FIG. 2, for instance, the substrate used for producing the wiper 12 as shown in FIG. 1 includes a first fibrous sheet 28 and a second fibrous sheet 30. The first fibrous sheet 28, for instance, can comprise a spunbond web as described above. The spunbond web 28, for instance, can be comprised of polymer synthetic fibers, such as polypropylene fibers, and can have a basis weight of greater than about 6 gsm, such as greater than about 8 gsm, and less than about 35 gsm, such as less than about 28 gsm, such as less than about 21 gsm.

[0068] The second sheet 30, on the other hand, can comprise a hydroentangled web. In one aspect, for instance, the hydroentangled web can include an outer spunbond web 32 hydroentangled with cellulose fibers to form a cellulose fiber web 34. The spunbond web 32 used to form thehydroentangled web 30, for instance, can have a basis weight of from about 6 gsm to about 35 gsm, such as from about 7 gsm to about 28 gsm, such as from about 8 gsm to about 21 gsm. The spunbond web 32 is hydroentangled with cellulose fibers such that there is fiber entanglement between the two layers to form a single web. The cellulose fibers, however, can be hydroentangled with the spunbond web 32 in a manner such that a distinct cellulose fiber layer 34 is formed. The cellulose fiber layer can be comprised, for instance, of pulp fibers, such as wood pulp fibers, non-wood pulp fibers, or mixtures thereof. In one aspect, the hydroentangled web 30 is formed by hydroentangling the spunbond web 32 with a cellulose fiber web 34.

[0069] The cellulose fiber web, for instance, can comprise a tissue web made from pulp fibers. The tissue web, for instance, can comprise an airlaid web or a wetlaid web including foam formed webs. In general, any suitable tissue web can be used to form the cellulose fiber layer 34 or the hydroentangled web 30. The tissue web can be formed through creping, wet creping, double creping, embossing, wet pressing, air pressing, through-air drying, creped through-air drying, uncreped through-air drying, airlaying, as well as any other processes known in the art.

[0070] In one aspect, the tissue web contains cellulose fibers in an amount greater than about 70% by weight, such as in an amount greater than about 80% by weight, such as in an amount greater than about 90% by weight, such as in an amount of 100% by weight.

[0071] In one aspect, the tissue web can be formed without a substantial amount of inner fiber-to-fiber bond strength. In this regard, the fiber furnish used to form the base web can be treated with a chemical debonding agent. The debonding agent can be added to the fiber slurry during the pulping process or can be added directly to the headbox. Suitable debonding agents that may be used in the present disclosure include cationic debonding agents such as fatty dialkyl quaternary amine salts, mono fatty alkyl tertiary amine salts, primary amine salts, imidazoline quaternary salts, silicone quaternary salt and unsaturated fatty alkyl amine salts. Other suitable debonding agents are disclosed in U.S. Pat. No. 5,529,665 to Kaun which is incorporated herein by reference. In particular, Kaun discloses the use of cationic silicone compositions as debonding agents.

[0072] In one embodiment, the debonding agent used in the process of the present disclosure is an organic quaternary ammonium chloride and, particularly, a silicone-based amine salt of a quaternary ammonium chloride. For example, the debonding agent can be PROSOFT® TQ1003, marketed by the Hercules Corporation. The debonding agent can be added to the fiber slurry in an amount of from about 1 kg per metric tonne to about 10 kg per metric tonne of fibers present within the slurry.

[0073] In an alternative embodiment, the debonding agent can be an imidazoline-based agent. The imidazoline-based debonding agent can be obtained, for instance, from the Witco Corporation. The imidazoline-based debonding agent can be added in an amount of between 2.0 to about 15 kg permetric tonne.

[0074] In one embodiment, the debonding agent can be added to the fiber furnish according to a process as disclosed in PCT Application having an International Publication No. WO 99 / 34057 filed on Dec. 17, 1998 or in PCT Published Application having an International Publication No. WO 00 / 66835 filed on Apr. 28, 2000, which are both incorporated herein by reference. In the above publications, a process is disclosed in which a chemical additive, such as a debonding agent, is adsorbed onto cellulosic papermaking fibers at high levels. The process includes the steps of treating a fiber slurry with an excess of the chemical additive, allowing sufficient residence time for adsorption to occur, filtering the slurry to remove unadsorbed chemical additives, and redispersing the filtered pulp with fresh water prior to forming a nonwoven web.

[0075] The basis weight of the tissue web 34 that is hydroentangled to the spunbond web 32 can be from about 12 gsm to about 120 gsm. For instance, the basis weight can be greater than about 20 gsm, such as greater than about 30 gsm, such as greater than about 35 gsm, such as greater than about 40 gsm, such as greater than about 45 gsm, such as greater than about 50 gsm, such as greater than about 55 gsm, such as greater than about 60 gsm, and less than about 90 gsm, such as less than about 85 gsm, such as less than about 80 gsm, such as less than about 75 gsm, such as less than about 70 gsm.

[0076] As shown in FIG. 2, the first sheet 28 is combined with the second sheet 30 such that the cellulose fiber layer 34 forms a middle layer in the wiper product.

[0077] Referring to FIG. 3, another embodiment of a substrate containing two fibrous sheets that can be used to produce the wiper 12 in accordance with the present disclosure is shown. In this embodiment, the substrate includes a first sheet 36 and a second sheet 38. The first sheet 36 and the second sheet 38 can comprise hydroentangled webs that can be similar in construction to the hydroentangled web 30 as shown in FIG. 2.

[0078] The first hydroentangled web 36 can include a spunbond layer 40 and a cellulose fiber layer 42. The second hydroentangled web 38 can also include a spunbond layer 44 and a cellulose fiber layer 46. The first hydroentangled web 36 can be combined with the second hydroentangled web 38 such that the two cellulose layers 42 and 46 form a middle layer 26 of the wiping product 12 as shown in FIG. 1.

[0079] In the embodiment illustrated in FIG. 3, two hydroentangled webs can be brought together which may be used to increase the basis weight of the middle cellulose fiber layer in the final wiping product. Using two hydroentangled webs also produces a wiper 12 having similar properties on each side of the product. Using two hydroentangled webs may also increase softness and provide a more cloth-like feel.Referring to FIG. 4, still another embodiment of a substrate that can be used to produce the wiping product 12 shown in FIG. 1 is illustrated. In FIG. 4, the substrate includes a first sheet 48, a second sheet 50, and a third sheet 52 that is positioned between the first sheet 48 and the second sheet 50. In this embodiment, the first and second sheets 48 and 50 can comprise nonwoven webs containing primarily or exclusively polymer synthetic fibers. The third sheet 52, on the other hand, can comprise a nonwoven web containing primarily or exclusively cellulose fibers, such as a tissue web as described above.

[0080] For instance, in one aspect, the first sheet 48 and the second sheet 50 can comprise spunbond webs. The spunbond webs can have a basis weight of greater than about 6 gsm, such as greater than about 8 gsm, and less than about 35 gsm, such as less than about 30 gsm, such as less than about 28 gsm, such as less than about 26 gsm, such as less than about 24 gsm, such as less than about 21 gsm. The middle sheet 52, on the other hand, can comprise a tissue web containing a homogeneous mixture of cellulose fibers such as wood pulp fibers, non-wood pulp fibers, or mixtures thereof. The middle layer 52 or tissue web can have a basis weight of from about 12 gsm to about 120 gsm. For instance, the tissue web 52 can have a basis weight of greater than about 24 gsm, such as greater than about 28 gsm, and less than about 100 gsm, such as less than about 90 gsm, such as less than about 85 gsm.

[0081] In order to form the wiper 12 as shown in FIG. 1 , the substrates illustrated, for instance, in FIGS. 2-4, can be fed through an embossing process, such as the embossing process as illustrated in FIG. 5 (two-sheet embodiment) and FIG. 6 (three-sheet embodiment).

[0082] For example, referring to FIG. 5, an embossing process is shown for converting the substrate illustrated in FIG. 2 into the wiper 12 as shown in FIG. 1. As shown, the first sheet or spunbond web 28 is fed into the process 60 in conjunction with the second sheet or hydroentangled web 30. For example, the spunbond web 28 can be fed around guide rolls 62 and 68 and fed into an embossing nip 72. The embossing nip 72 is formed between a first embossing roll 66 and a second embossing roll 78.

[0083] As shown, the first embossing roll 66 includes a pattern of male embossing elements 70 that emboss a pattern into the spunbond web when fed into the embossing nip 72. Similarly, hydroentangled web 30 is fed around guide rolls 74 and 76 and placed in contact with a second embossing roll 78. The second embossing roll 78 includes a pattern of male embossing elements 80.

[0084] As shown, the spunbond web 28 is placed in contact with the hydroentangled web 30 and fed into the embossing nip 72 for forming embossments in both sides of the substrates or sheets. The embossments attach the two sheets 28 and 30 together and form the wiper 12.

[0085] In accordance with the present disclosure, at least a portion of the male embossing elements70 on the first embossing roll 66 align with at least some of the male embossing elements 80 on the second embossing roll 78. For example, greater than about 70%, such as greater than about 80%, such as greater than about 90% of the male embossing elements 70 can align with the male embossing elements 80. In one aspect, the first pattern of male embossing elements 70 exactly matches the pattern of male embossing elements 80 on the second embossing roll 78. Thus, the process 60 shown in FIG. 5 can be considered a pin-to-pin embossing process that produces embossments 22 and 24 as shown in FIG. 1 that align in the Z-direction. Having the embossments align allows for greater penetration into the wiper 12 along the vertical axis of the embossments. It was discovered that this embossing technique allows for the different fibrous sheets to be attached together without having to use thermal bonding or ultrasonic bonding.

[0086] As shown in FIG. 5, the spunbond web 28 is guided onto the embossing roll 66 such that the spunbond web is wrapped around the embossing roll greater than about 90°, such as greater than about 180°, such as greater than about 200°. The hydroentangled web 30, on the other hand, is wrapped around the second embossing roll 78 in an amount of from about 20° to about 100°. It should be understood that the amount the webs are wrapped around the embossing rolls can vary depending upon the particular application and desired result. In an alternative embodiment, the webs can be fed directly into the embossing nip 72 without being wrapped around the corresponding embossing rolls.

[0087] Within the embossing nip 72, the spunbond web 28 and the hydroentangled web 30 are embossed and attached together to produce the wiper 12. Within the embossing nip 72, the two webs are subjected to sufficient pressure for the male embossing elements to form the embossments 22 and 24 as shown in FIG. 1. The pressure, temperature, and time within the nip can be controlled for controlling the amount of penetration and embossment. In one aspect, the embossing rolls 66 and 78 can be heated for facilitating the process. The embossing rolls 66 and 78 can be heated sufficient for thermal bonds to form. In alternative embodiments, however, the embossing rolls 66 and 78 are maintained below the softening point of the polymers contained in the fibrous sheets so that embossing takes place without forming thermal bonds.

[0088] The male embossing elements 70 and 80 can have any suitable shape. In one aspect, the embossing elements comprise discrete shapes. For instance, the top surface of each male embossing element can be circular, oval, triangular, rectangular, or can have an irregular shape. The male embossing elements can be positioned on the surface of each embossing roll in a random pattern or in a more discernible repeating pattern. In one aspect, for instance, the male embossing elements are positioned on each embossing roll so as to form rows and / or columns. The male embossing elements, for instance, can be equally spaced within each row, equally spaced within each column, or can beuniformly populated over the surface of the embossing roll.

[0089] In one aspect, the embossing patterns can include male embossing elements that form discontinuous line structures on the embossing roll. For instance, in one embodiment, the male embossing elements can form wave-like discontinuous line structures over the surface of the embossing roll. Each wave-like line structure can be spaced from an adjacent wave-like line structure.

[0090] When the male embossing elements are in the form of discrete shapes, the top surface of each male embossing element can have the same size or, alternatively, can have different sizes within the pattern. In one aspect, when applying a best fit circle around the top surface of each male embossing element, each male embossing element can have a diameter of generally greater than about 0.1 mm, such as greater than about 0.2 mm, such as greater than about 0.25 mm, such as greater than about 0.3 mm, such as greater than about 0.35 mm, such as greater than about 0.4 mm, and less than about 8 mm, such as less than about 5 mm, such as less than about 3 mm, such as less than about 1.5 mm, such as less than about 1.2 mm, such as less than about 1 mm, such as less than about 0.8 mm, such as less than about 0.6 mm.

[0091] The male embossing elements on one embossing roll can be the same size or can have a different size than the male embossing elements on an opposing embossing roll. For instance, for the embossing elements in alignment on the two rolls, in one embodiment, the embossing elements on one roll can be larger or have a larger diameter than the corresponding embossing elements on the opposing roll.

[0092] The height of the male embossing elements can also vary. In one aspect, the male embossing elements have a height of greater than about 0.4 mm, such as greater than about 0.6 mm, such as greater than about 0.8 mm, such as greater than about 1 mm. The height of the male embossing elements can be less than about 10 mm, such as less than about 7 mm, such as less than about 4 mm, such as less than about 3.5 mm, such as less than about 3 mm, such as less than about 2.5 mm, such as less than about 2 mm. The height of the male embossing elements on one embossing roll can be the same or different.

[0093] Referring to FIG. 6, another embossing process 60 in accordance with the present disclosure is shown. The process illustrated in FIG. 6 is similar to the process illustrated in FIG. 5 except that an additional fibrous sheet is fed into the embossing nip. Like reference numerals have been used to indicate similar elements.

[0094] In FIG. 6, a first spunbond web 48 and a second spunbond web 50 are fed to the process in conjunction with a tissue web 52 that forms the middle layer of the wiper 12. As shown, the spunbond web 48 contacts guide rolls 62 and 68 and is fed into the embossing nip 72. The tissue web or cellulose web 52 contacts guide rolls 82 and 84 and is placed in an overlapping relationship with thespunbond web 48 and fed into the embossing nip 72. The spunbond web 50 is also fed into the embossing nip 72 via the guide rolls 74 and 76.

[0095] Embossing nip 72 is formed between the first embossing roll 66 and the second embossing roll 78. Each embossing roll 66 and 78 includes a pattern of male embossing elements 70 and 80. At least some of the male embossing elements on one embossing roll are in alignment with at least some of the embossing elements on the opposing embossing roll for forming embossments into the three-sheet structure. The embossing process not only forms embossments into the spunbond webs 40 and 50, but also attaches the three fiber sheets together.

[0096] Referring to FIG. 1, as shown, the embossments 22 and 24 formed through the embossing process can extend into the middle layer 26. For instance, the embossments can extend through at least 10% of the thickness, such as at least 20% of the thickness, such as at least 30% of the thickness, such as at least 40% of the thickness of the wiper 12. The embossments 22 and 24 generally extend less than 45% of the thickness, such as less than about 30% of the thickness of the wiper 12.

[0097] The density of the embossments on each surface of the wiper 12 can vary depending upon the particular application and the different types of webs that are attached together. The embossments 22 or 24, for instance, can occupy greater than about 5%, such as greater than about 10%, such as greater than about 15%, such as greater than about 20%, such as greater than about 25%, such as greater than about 30%, such as greater than about 35%, such as greater than about 40% of the surface area of each outer surface of the wiper 12. The embossments 22 or 24 can occupy less than about 65%, such as less than about 55%, such as less than about 45%, such as less than about 35%, such as less than about 25% of the surface area of each outer surface of the wiper 12.

[0098] After the multiple sheets are embossed together and formed into the wiper 12, the resulting composite may be wound and stored on a take-up roll. Various additional potential processing and / or finishing steps, such as slitting, treating, printing, graphics, etc., may be performed.

[0099] The wiper 12 as shown in FIG. 1 can be packaged and shipped as a roll of material or can be cut into individual sheets. For instance, the wiper can have a length and / or width between about 2” and about 40" or between about 4” and about 36". In one aspect, the wiper may have a width and height of about 4” x 4”, or about 4” by about 8”, or about 8” by about 8”, or about 12” x 12", or about 16” x 16”, or about 12” x 18”, or about 18” x 24”, or about 18” by about 36”, or about 24” by about 36”. The wiper can have a rectangular shape, square shape, or the like.

[0100] In one embodiment, the wiper can be cut into individual sheets and then stacked and packaged. Alternatively, the wipers can be packaged individually. In one embodiment, the wipers arestacked and / or packaged in a dry state.

[0101] As described above, wipers made according to the present disclosure are well suited to absorbing and retaining oils, greases, water, and other liquids. For instance, wipers made according to the present disclosure can display an oil absorption when tested against SAE 50 oil of greater than about 4.5 grams of oil per gram of wiper, such as greater than about 5 grams of oil per gram of wiper, such as greater than about 5.5 grams of oil per gram of wiper, such as greater than about 6 grams of oil per gram of wiper, such as greater than about 6.5 grams of oil per gram of wiper, such as greater than about 7 grams of oil per gram of wiper, such as greater than about 7.5 grams of oil per gram of wiper, and less than about 20 grams of oil per gram of wiper. The wipers can also display excellent water absorption properties. For instance, the wipers can display a water absorption of greater than about 3.5 grams of water per gram of wiper, such as greater than about 4 grams of water per gram of wiper, such as greater than about 4.2 grams of water per gram of wiper, such as greater than about 4.4 grams of water per gram of wiper, such as greater than about 4.6 grams of water per gram of wiper, and less than about 20 grams of water per gram of wiper.

[0102] Other parameters that can impact the cleaning properties of the wiper include the void volume of the product. This parameter determines the amount of open space within the interstices of the wiper. The void volume (can also be referred to as the intrinsic void volume) of the wiper, for instance, can generally be greater than about 20%, such as greater than about 40%, such as greater than about 60%, such as greater than about 70%, such as greater than about 75%, such as greater than about 80%, and generally less than about 96%, such as less than about 90%. The void volume of the nonwoven material can be measured under pressure, such as at a pressure of 0.3 psi.

[0103] Wipers made according to the present disclosure can generally have a density of greater than about 0.1 g / cm3when tested at a pressure of 0.05 psi. The density of the wiper, for instance, can be greater than about 0.12 g / cm3and less than about 3 g / cm3, such as less than about 1.8 g / cm3.

[0104] The caliper of the web can generally be from about 0.4 mm to about 4 mm, including all increments of 0.1 mm therebetween. For instance, the caliper of the web can be greater than about 0.5 mm, such as greater than about 0.6 mm, such as greater than about 0.7 mm. The caliper can be less than about 2.5 mm, such as less than about 2 mm, such as less than about 1.5 mm, such as less than about 1.3 mm. The caliper can be measured at an applied pressure of 0.05 psi.

[0105] The basis weight of nonwoven materials made in accordance with the present disclosure can be anywhere from about 30 gsm to about 200 gsm, including all increments of 1 gsm therebetween. For example, in one aspect, the basis weight can be less than about 130 gsm, such as less than about 120 gsm, such as less than about 110 gsm. The basis weight is generally greater than about 35 gsm, such as greater than about 40 gsm, such as greater than about 45 gsm.The present disclosure may be better understood with reference to the following example.

[0106] Example

[0107] Various wipers were produced in accordance with the present disclosure and tested for oil absorbency and water absorbency.

[0108] The samples made according to the present disclosure were formed from a spunbond web attached to a hydroentangled web using an embossing process similar to the one illustrated in FIG. 5.

[0109] The hydroentangled web was formed from a spunbond web hydroentangled with a wood pulp base sheet. The hydroentangled web was combined with the spunbond web in order to form a middle layer comprised of wood pulp fibers.

[0110] The following samples were produced:

[0111]

[0112] The above wipers were tested for oil absorbency and water absorbency. For purposes of comparison, two commercially available wipers were also tested. In a first set of experiments, Sample Nos. 1-3 were compared with WYPALL X80 wiper and in a second set of experiments, Sample Nos. 2, 4, and 5 were tested in comparison to WYPALL X70 wiper.

[0113] The results are graphically illustrated in FIGS. 7 and 8. As shown, the oil absorbency of wipers made according to the present disclosure was dramatically and unexpectedly better than the commercial samples.

[0114] These and other modifications and variations to the present invention may be practiced by those of ordinary skill in the art, without departing from the spirit and scope of the present invention, which is more particularly set forth in the appended claims. In addition, it should be understood that aspects of the various embodiments may be interchanged both in whole or in part. Furthermore, those of ordinary skill in the art will appreciate that the foregoing description is by way of example only and is not intended to limit the invention so further described in such appended claims.

Claims

What Is Claimed:

1. A wiper comprising:at least a first sheet attached to a second sheet by embossments, the wiper including a first outer surface opposite a second outer surface, the wiper including at least three layers, the three layers including a first outer nonwoven layer comprised of polymer synthetic fibers, a second outer nonwoven layer comprised of polymer synthetic fibers, and a middle layer positioned between the first nonwoven outer layer and the second nonwoven outer layer, the middle layer comprising cellulose fibers and being free of polymer synthetic fibers, and wherein the embossments include a first pattern of embossments extending into the first outer surface and a second pattern of embossments extending into the second outer surface, and wherein at least a portion of the embossments of the first pattern align with at least a portion of the embossments of the second pattern.

2. A wiper as defined in claim 1 , wherein the first pattern of embossments and the second pattern of embossments extend into the middle layer.

3. A wiper as defined in claim 1 or 2, wherein the wiper is constructed only from the first sheet and the second sheet.

4. A wiper as defined in any of the preceding claims, wherein the first sheet comprises a spunbond web and the second sheet comprises a hydroentangled web comprising a nonwoven web comprised of polymer synthetic fibers hydroentangled with cellulose fibers, the cellulose fibers forming the middle layer of the wiper.

5. A wiper as defined in any of claims 1-3, wherein the first sheet comprises a hydroentangled web comprising a nonwoven web comprised of polymer synthetic fibers hydroentangled with cellulose fibers and the second sheet comprises a hydroentangled web comprising a nonwoven web comprised of polymer synthetic fibers hydroentangled with cellulose fibers, and wherein the cellulose fibers from the first sheet and the cellulose fibers of the second sheet form the middle layer of the wiper.

6. A wiper as defined in claim 1 or 2, wherein the wiper is comprised of the first sheet, the second sheet, and a third sheet that are attached together by the embossments.

7. A wiper as defined in claim 6, wherein the first sheet comprises a spunbond web and the second sheet comprises a spunbond web, and wherein the third sheet comprises a tissue web comprised of the cellulose fibers, the third sheet being positioned between the first sheet and the second sheet.

8. A wiper as defined in any of the preceding claims, wherein the first layer comprises a spunbond web and the second layer comprises a spunbond web.

9. A wiper as defined in any of the preceding claims, wherein the cellulose fiberscontained in the middle layer comprise pulp fibers, the pulp fibers comprising wood pulp fibers, nonwood pulp fibers, or mixtures thereof.

10. A wiper as defined in any of the preceding claims, wherein the wiper displays an oil absorbency of greater than about 4.5 grams of oil per gram of wiper, such as greater than about 5 grams of oil per gram of wiper, such as greater than about 5.5 grams of oil per gram of wiper, such as greater than about 6 grams of oil per gram of wiper, and less than about 20 grams of oil per gram of wiper, and displays a water absorbency of greater than about 3.5 grams of water per gram of wiper, such as greater than about 4 grams of water per gram of wiper, such as greater than about 4.2 grams of water per gram of wiper, and less than about 20 grams of water per gram of wiper.

11. A wiper as defined in any of the preceding claims, wherein the embossments in the first pattern comprise discrete shapes and the embossments in the second pattern comprise discrete shapes.

12. A wiper as defined in any of the preceding claims, wherein the first pattern of embossments on the first outer surface occupy greater than about 5% of the surface area of the first outer surface, such as greater than about 15% of the surface area of the first outer surface, such as greater than about 25% of the surface area of the first outer surface, such as greater than about 30% of the surface area of the first outer surface, such as greater than about 35% of the surface area of the first outer surface, such as greater than about 40% of the surface area of the first outer surface, and less than about 70% of the surface area of the first outer surface, and wherein the second pattern of embossments on the second outer surface occupies greater than about 15% of the surface area of the second outer surface, such as greater than about 20% of the surface area of the second outer surface, such as greater than about 25% of the surface area of the second outer surface, such as greater than about 30% of the surface area of the second outer surface, such as greater than about 35% of the surface area of the second outer surface, such as greater than about 40% of the surface area of the second outer surface, and less than about 70% of the surface area of the second outer surface.

13. A wiper as defined in any of the preceding claims, wherein greater than about 50% of the embossments of the first pattern, such as greater than about 80% of the embossments of the first pattern, such as greater than about 90% of the embossments of the first pattern align with the embossments of the second pattern.

14. A wiper as defined in any of the preceding claims, wherein the wiper has a caliper of greater than about 0.4 mm, such as greater than about 0.5 mm, such as greater than about 0.6 mm, such as greater than about 0.7 mm, and less than about 2 mm.

15. A wiper as defined in any of the preceding claims, wherein the wiper has a basis weight of from about 35 gsm to about 200 gsm, such as from about 40 gsm to about 130 gsm.

16. A wiper as defined in any of the preceding claims, wherein the first sheet and the second sheet are attached together without forming any thermal bonds or ultrasonic bonds.

17. A wiper as defined in any of the preceding claims, wherein the wiper displays a void volume of greater than about 60%, such as greater than about 70%, such as greater than about 75% when tested at 0.3 psi.

18. A wiper as defined in claim 8, wherein each of the spunbond webs independently have a basis weight of from about 6 gsm to about 28 gsm, such as from about 8 gsm to about 21 gsm.

19. A wiper as defined in any of the preceding claims, wherein the cellulose fibers in the middle layer have a basis weight of from about 12 gsm to about 120 gsm, such as from about 25 gsm to about 90 gsm.

20. A wiper as defined in claim 7, wherein the tissue web comprises an uncreped through-air dried web or a creped web.

21. A wiper as defined in any of the preceding claims, wherein the polymeric synthetic fibers contained in the wiper comprise a polypropylene polymer, and wherein the wiper is free of polyester fibers.

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