Bulky nonwoven fabric

Abstract

A nonwoven fabric comprises a first plurality of randomly oriented single fibers and a second plurality of randomly oriented single fibers, which together form a nonwoven web. The first plurality of randomly oriented single fibers is present within the nonwoven web with not less than seventy percent by weight, and the second plurality of randomly oriented single fibers is present within the nonwoven web with not less than two percent and not more than twenty percent by weight. A section of the nonwoven web is embossed.

Description

BACKGROUND

[0001] Nonwoven fabrics are often embossed to add surface features such as patterns or textures. In recent years, the speed at which nonwoven fabrics can be embossed has increased significantly. However, embossing the nonwoven fabric to achieve high bulk or strength at these increased speeds has been challenging. Furthermore, high-speed embossing can limit the nonwoven fabric's bulk to an undesirably low level.

[0002] A nonwoven fabric with properties that facilitate the formation of bulky embossing on the nonwoven fabric would be useful. Furthermore, a nonwoven fabric with properties that facilitate the formation of bulky embossing at high speeds would be useful. OVERVIEW

[0003] In general, the present disclosure relates to a nonwoven fabric having features that facilitate the formation of bulky embossments. The nonwoven fabric may include a nonwoven fibrous web formed jointly by a first plurality of randomly oriented individual fibers and a second plurality of randomly oriented individual fibers. The second plurality of randomly oriented individual fibers may be smaller than the first plurality of randomly oriented individual fibers. For example, the second plurality of randomly oriented individual fibers may be meltblown fibers and the first plurality of randomly oriented individual fibers may be spunbonded fibers. For example, the second plurality of randomly oriented individual fibers may be in a microfiber size range. The second plurality of randomly oriented individual fibers may be present in the nonwoven fibrous web at a weight percentage of not less than two weight percent (2 wt.-%) and no more than twenty weight percent (20 wt.%) of the nonwoven web. The second plurality of randomly oriented individual fibers can help maintain the nonwoven web in a desired bulk, such as a 3D shape, when the nonwoven web is embossed at high speeds, e.g., between two hundred meters per second (200 m / s) and one thousand meters per second (1000 m / s). Thus, the nonwoven web can be embossed or thermally bonded while advantageously maintaining the desired bulk. The "bulky" embossed fabric can be incorporated into absorbent articles such as sanitary pads, diapers, disposable underwear, etc.

[0004] In an exemplary embodiment, a nonwoven fabric includes a first plurality of randomly oriented individual fibers and a second plurality of randomly oriented individual fibers that together form a nonwoven fibrous web. A ratio of an average diameter of the first plurality of randomly oriented individual fibers to an average diameter of the second plurality of randomly oriented individual fibers is between 50:1 and 3:1. The first plurality of randomly oriented individual fibers are present within the nonwoven fibrous web at no less than seventy percent by weight of the nonwoven fibrous web, and the second plurality of randomly oriented individual fibers are present within the nonwoven fibrous web at no less than two percent by weight of the nonwoven fibrous web and no more than twenty percent by weight of the nonwoven fibrous web. A portion of the nonwoven web is embossed.

[0005] In a first exemplary aspect, the first plurality of randomly oriented individual fibers may be made of polypropylene fibers and the second plurality of randomly oriented individual fibers may be made of polypropylene fibers.

[0006] In a second exemplary aspect, the first plurality of randomly oriented individual fibers may be comprised of spunbonded polypropylene fibers and the second plurality of randomly oriented individual fibers may be comprised of meltblown polypropylene fibers.

[0007] In a third exemplary aspect, the average diameter of the first plurality of randomly oriented individual fibers may be no less than ten micrometers and no more than twenty-two micrometers, and the average diameter of the second plurality of randomly oriented individual fibers may be no less than half a micrometer and no more than three micrometers.

[0008] In a fourth exemplary aspect, the average diameter of the first plurality of randomly oriented individual fibers is not less than twelve micrometers and not more than eighteen micrometers, and the average diameter of the second plurality of randomly oriented individual fibers is not less than seven-tenths of a micrometer and not more than two micrometers.

[0009] In a fifth exemplary aspect, the average thickness of the nonwoven web in an unembossed portion of the nonwoven web may be no less than three times greater than the average thickness of the nonwoven web in the embossed portion of the nonwoven web.

[0010] In a sixth exemplary aspect, the average thickness of the nonwoven web in the unembossed portion of the nonwoven web may be no less than five times greater than the average thickness of the nonwoven web in the embossed portion of the nonwoven web.

[0011] In a seventh exemplary aspect, the average thickness of the nonwoven fibrous web in the unembossed portion of the nonwoven fibrous web may be not less than one hundred micrometers and not more than about three hundred micrometers, and the average thickness of the nonwoven fibrous web in the embossed portion of the nonwoven fibrous web may be not less than five hundred micrometers and not more than three thousand micrometers.

[0012] In an eighth exemplary aspect, the nonwoven web may define a plurality of apertures extending through a thickness of the nonwoven web.

[0013] In a ninth exemplary aspect, a product may include the embossed nonwoven fabric. The product may be a diaper, a disposable undergarment, an incontinence pad, or a sanitary napkin.

[0014] Each of the above example aspects may, in certain embodiments, be combined with one or more of the other above example aspects. For example, in some embodiments, all of the above nine example aspects may be combined with each other. As another example, in other embodiments, any combination of two, three, four, five, or more of the above nine example aspects may be combined. Therefore, in some example embodiments, the above example aspects may be used in combination with each other. Alternatively, in other example embodiments, the above example aspects may be implemented individually. Accordingly, it should be understood that various example embodiments may be implemented using the above example aspects.

[0015] In another exemplary embodiment, a nonwoven fabric includes a plurality of randomly oriented, individual, spunbonded polypropylene fibers and a plurality of randomly oriented, individual, meltblown polypropylene fibers that together form a nonwoven web. A ratio of an average diameter of the plurality of randomly oriented individual spunbonded polypropylene fibers to an average diameter of the plurality of randomly oriented individual meltblown polypropylene fibers is between 60:1 and 2:1.The plurality of randomly oriented individual spunbonded polypropylene fibers are present within the nonwoven web at not less than seventy percent by weight of the nonwoven web, and the plurality of randomly oriented individual meltblown polypropylene fibers are present within the nonwoven web at not less than two percent by weight of the nonwoven web and not more than twenty percent by weight of the nonwoven web. A portion of the nonwoven web is embossed such that the average thickness of the nonwoven web in an unembossed portion of the nonwoven web is not less than three times greater than the average thickness of the nonwoven web in the embossed portion of the nonwoven web.

[0016] In a tenth exemplary aspect, the average diameter of the plurality of randomly oriented individual spunbond polypropylene fibers can be no less than ten micrometers and no more than twenty-two micrometers, and the average diameter of the plurality of randomly oriented individual meltblown polypropylene fibers can be no less than half a micrometer and no more than three micrometers.

[0017] In an eleventh exemplary aspect, the average diameter of the plurality of randomly oriented individual spunbond polypropylene fibers can be no less than twelve micrometers and no more than eighteen micrometers, and the average diameter of the plurality of randomly oriented individual meltblown polypropylene fibers can be no less than seven-tenths of a micrometer and no more than two micrometers.

[0018] In a twelfth exemplary aspect, the average thickness of the nonwoven web in the unembossed portion of the nonwoven web may be no less than five times greater than the average thickness of the nonwoven web in the embossed portion of the nonwoven web.

[0019] In a thirteenth exemplary aspect, the average thickness of the nonwoven fibrous web in the unembossed portion of the nonwoven fibrous web may be not less than one hundred micrometers and not more than about three hundred micrometers, and the average thickness of the nonwoven fibrous web in the embossed portion of the nonwoven fibrous web may be not less than five hundred micrometers and not more than three thousand micrometers.

[0020] In a fourteenth exemplary aspect, the nonwoven web may define a plurality of apertures extending through a thickness of the nonwoven web.

[0021] Each of the above example aspects may, in certain embodiments, be combined with one or more of the other above example aspects. For example, in some embodiments, all five of the above example aspects (i.e., example aspects ten through fourteen) may be combined with each other. As another example, in other embodiments, any combination of two, three, or four of the above five example aspects may be combined. Therefore, in some example embodiments, the above example aspects may be used in combination with each other. Alternatively, in other example embodiments, the above example aspects may be implemented individually.Accordingly, it should be understood that various exemplary embodiments may be implemented using the above exemplary aspects.

[0022] In another exemplary embodiment, a method of forming an embossed nonwoven fabric includes: bonding a blend of a plurality of randomly oriented individual spunbonded polypropylene fibers and a plurality of randomly oriented individual meltblown polypropylene fibers to form a nonwoven web, wherein the plurality of randomly oriented individual spunbonded polypropylene fibers are present within the blend at no less than seventy percent by weight of the blend, wherein the plurality of randomly oriented individual meltblown polypropylene fibers are present within the blend at a weight percentage of no less than two percent and no more than twenty percent of the blend;and embossing a portion of the nonwoven web such that an average thickness of the nonwoven web in an unembossed portion of the nonwoven web is not less than three times greater than the average thickness of the nonwoven web in the embossed portion of the nonwoven web;

[0023] In a fifteenth exemplary aspect, the speed of the nonwoven web during embossing may be no less than two hundred meters per second and no more than one thousand meters per second.

[0024] In a sixteenth exemplary aspect, the ratio of an average diameter of the plurality of randomly oriented individual spunbond polypropylene fibers to an average diameter of the plurality of randomly oriented individual meltblown polypropylene fibers may be between 50:1 and 3:1.

[0025] The fifteenth and sixteenth exemplary aspects may be combined in certain exemplary embodiments.

[0026] These and other features, aspects, and advantages of the present disclosure will become more fully understood with reference to the following description and the appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the disclosure and, together with the description, serve to explain the principles of the disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] A complete and enabling disclosure of the present disclosure, including the best mode thereof directed to one of ordinary skill in the art, is set forth in the specification with reference to the accompanying figures. Fig. 1 is a side view of a nonwoven fabric according to an exemplary embodiment of the present disclosure. Fig. 2 is a plan view of the exemplary nonwoven fabric of Fig. 1. Fig. 3 is a schematic view of an embossing apparatus for a nonwoven fabric according to an exemplary embodiment of the present disclosure. Fig. 4 is a partial sectional view of the exemplary embossing device of Fig. 3. Fig. 5 illustrates a method of forming a nonwoven fabric according to an exemplary embodiment of the present disclosure. Fig. 6 is a scan of a nonwoven fabric according to an exemplary embodiment of the present disclosure. Fig. Figure 7 is a graphical representation of a thickness of the nonwoven fabric of Fig. 6.

[0028] The repeated use of reference numerals in this specification and the drawings is intended to represent the same or analogous features or elements of the present invention. DETAILED DESCRIPTION

[0029] Those skilled in the art will understand that the present discussion is only a description of exemplary embodiments and is not intended to limit the broader aspects of the present disclosure.

[0030] As used herein, the terms "includes" and "including" are intended to be inclusive in a similar manner to the term "comprise." Likewise, the term "or" is generally intended to be inclusive (i.e., "A or B" is intended to mean "A or B or both"). The approximate language used throughout the specification and claims is used to modify any quantitative representation that could permissibly vary without causing a change in the basic function to which it relates. Accordingly, a value modified by one or more terms such as "about," "approximately," and "substantially" may not be limited to the precisely stated value. In at least some cases, the approximate language may correspond to the precision of an instrument used to measure the value. For example, the approximate language may refer to a value within a tolerance of ten percent (10%).

[0031] As used herein, the term "fiber" refers to any type of man-made fiber, filament, or fibril, whether continuous or discontinuous, produced by a spinning process, a meltblowing process, a melt fibrillation or film fibrillation process, an electrospinning production process, or any other suitable process. As used herein, the term "nonwoven" means a porous, fibrous material made from continuous (long) filaments (fibers) and / or discontinuous (short) filaments (fibers) by processes such as spunbonding, meltblowing, carding, and the like. "Nonwoven" does not include film, woven fabric, or knitted fabric.

[0032] With reference to Fig. 1 and Fig. 2, a nonwoven fabric 100 is illustrated according to an exemplary embodiment of the present disclosure. Nonwoven fabric 100 may include a fibrous nonwoven web 110 formed from a first plurality of randomly oriented single fibers and a second plurality of randomly oriented single fibers that are bonded together. The first and second plurality of randomly oriented single fibers may have different sizes. Additionally, the first plurality of randomly oriented single fibers may be larger than the second plurality of randomly oriented single fibers. For example, an average diameter of the first plurality of randomly oriented single fibers may be larger than an average diameter of the second plurality of randomly oriented single fibers.As described in more detail below, the size difference between the first and second plurality of randomly oriented individual fibers may advantageously help the nonwoven web 110 maintain a desired bulk during bonding and / or embossing of the nonwoven web 110.

[0033] As in Fig. 1 and Fig. 2, the nonwoven web 110 may be embossed to provide a desired pattern and / or texture on the nonwoven web 110.

[0034] Furthermore, the nonwoven web 110 may define a first surface 102 and a second surface 104, for example, being arranged opposite one another on the nonwoven web 110. The nonwoven web 110 may be embossed to form embossed portions 112 and puffed portions 116 on the nonwoven web 110. For example, the embossed portions 112 may be formed into troughs or valleys 118 (represented by the "X" in Fig. 2) on the first surface 102 of the nonwoven web 110, and the bulged portions 116 may correspond to protrusions or tips 116 (represented by the “O”s in Fig. 2) on the first surface 102 of the nonwoven web 110. As in Fig. 2, the embossed portions 112 and the puffed portions 116 may be distributed in a plurality of rows 120, 122, 124 and / or a plurality of columns 130, 132, 134 on the first surface 102 of the nonwoven web 110. The nonwoven web 110 may extend between a first end portion 105 and a second end portion 106, e.g., along a longitudinal direction L. The nonwoven web 110 may also extend between a first side portion 107 and a second side portion 108, e.g., along a transverse direction T that is perpendicular to the lateral direction L. The rows 120, 122, 124 may be spaced along the transverse direction T between first and second side portions 107, 108 of the nonwoven web 110, and columns 130, 132, 134 may be spaced along the lateral direction L between first and second end portions 105, 106 of the nonwoven web 110.It should be understood that such an exemplary pattern is provided only as an example and is not intended to limit the present disclosure to any particular arrangement of embossed portions 112 and lofted portions 116. Rather, the nonwoven web 110 may be embossed to provide any suitable pattern and / or texture of embossed portions 112 and lofted portions 116 on the nonwoven web 110.

[0035] A bulk or strength of a nonwoven web 110 may be different at the embossed portions 112 and the bulked portions 116. In particular, the caliper of the nonwoven web 110 at bulked portions 116 may be greater than the caliper of the nonwoven web 110 at embossed portions 112. Moreover, an average caliper TU of a nonwoven web 110 at bulked portions 116 of the nonwoven web 110 may be no less than three times (3X) greater than an average caliper TE of a nonwoven web 110 at embossed portions 112 of the nonwoven web 110. As another example, the average caliper TU of the nonwoven web 110 at bulked portions 116 may be no less than four times (4X) greater, five times (5X) greater, six times (6X) greater, ten times (10X) greater, twenty times (20X) greater, thirty times (6X) greater, or more than the average caliper TE of the nonwoven web 110 at the embossed portions 112.In certain exemplary embodiments, the average caliper TU of the nonwoven web 110 at bulked portions 116 may be no less than one hundred micrometers (100 µm) and no more than about three hundred micrometers (300 µm), and the average caliper TE of the nonwoven web 110 at the embossed portions 112 may be no less than five hundred micrometers (500 µm) and no more than three thousand micrometers (3000 µm). As can be seen from the foregoing, the nonwoven web 110 may advantageously have a significant difference in caliper between the embossed portions 112 and the bulked portions 116 of the nonwoven web 110. For example, nonwoven fabric 100 may be "bulky" and / or include a "3D" textured surface.

[0036] As illustrated, the average caliper TU of the nonwoven web 110 at lofted portions 116 of the nonwoven web 110 may correspond to the caliper of the nonwoven web 110 between the first surface 102 and the second surface 104 at lofted portions 116. Furthermore, the relevant caliper may be the maximum caliper of the nonwoven web 110 between the first surface 102 and the second surface 104 at each lofted portion 116. Conversely, the average caliper TE of the nonwoven web 110 at embossed portions 112 of the nonwoven web 110 may correspond to the caliper of the nonwoven web 110 between the first surface 102 and the second surface 104 at embossed portions 112. Furthermore, the relevant thickness may be the minimum thickness of the nonwoven web 110 between the first surface 102 and the second surface 104 at each embossed portion 112.

[0037] The first and second pluralities of randomly oriented individual fibers may be formed from a suitable plastic material. For example, the first plurality of randomly oriented individual fibers may be made from extruded polypropylene fibers, extruded polyethylene fibers, bonded carded web (BCW), etc. In certain exemplary embodiments, the first plurality of randomly oriented individual fibers may be made from spunbonded polypropylene fibers. The second plurality of randomly oriented individual fibers may also be made from extruded polypropylene fibers, extruded polyethylene fibers, bonded carded web (BCW), etc. In certain exemplary embodiments, the second plurality of randomly oriented individual fibers may be made from meltblown polypropylene fibers.

[0038] As noted above, the first plurality of randomly aligned single fibers may be relatively large compared to the second plurality of randomly aligned single fibers. For example, a ratio of an average diameter of the first plurality of randomly aligned single fibers to an average diameter of the second plurality of randomly aligned single fibers may be between 50:1 and 3:1, for example, between 26:1 and 6:1. In certain exemplary embodiments, the average diameter of the first plurality of randomly aligned single fibers may be larger than the average diameter of the second plurality of randomly aligned single fibers. As a specific example, the average diameter of the first plurality of randomly aligned single fibers may be no less than ten micrometers (10 µm) and no more than twenty-two micrometers (22 µm).In particular, the average diameter of the first plurality of randomly oriented individual fibers may be no less than twelve micrometers (12 µm) and no more than eighteen micrometers (18 µm). In certain exemplary embodiments, the average diameter of the second plurality of randomly oriented individual fibers may be no less than half a micrometer (0.5 µm) and no more than three micrometers (3 µm). In particular, the average diameter of the second plurality of randomly oriented individual fibers may be no less than seven-tenths (0.7 µm) of a micrometer and no more than two micrometers (2 µm). Such different sizing of the first and second pluralities of randomly oriented individual fibers may advantageously enable the formation of a nonwoven web 110 having the significant difference in thickness between the embossed portions 112 and the bulked portions 114 of the nonwoven web 110.

[0039] The first and second pluralities of randomly oriented individual fibers may be mixed and bonded to form a nonwoven fibrous web 110. The relative amounts of the first and second pluralities of randomly oriented individual fibers within the nonwoven fibrous web 110 may be selected to assist in forming the nonwoven fibrous web 110 with the significant difference in strength between the embossed portions 112 and the bulked portions 114 of the nonwoven fibrous web 110. The first plurality of randomly oriented individual fibers may be present within the nonwoven fibrous web 110 at a weight percentage of not less than seventy percent (70%), not less than eighty percent (80%), not less than ninety percent (90%), not less than ninety-five percent (95%), or more of the nonwoven fibrous web 110.In certain exemplary embodiments, the first plurality of randomly oriented individual fibers may be present within the nonwoven web 110 at a weight percentage of no less than seventy percent (70%) and no more than ninety-seven percent (97%) of the nonwoven web 110. The second plurality of randomly oriented individual fibers may be present within the nonwoven web 110 at a weight percentage of no less than two percent (2%), no less than three percent (3%), no less than five percent (5%), no less than eight percent (8%), no less than ten percent (10%), or no less than twelve percent (12%) of the nonwoven web 110.The second plurality of randomly oriented individual fibers may be present within the nonwoven web 110 at a weight of no more than five percent (5%), no more than eight percent (8%), no more than ten percent (10%), no more than twelve percent (12%), no more than fifteen percent (15%), no more than eighteen percent (18%), or no more than twenty percent (20%) of the nonwoven web 110. In certain exemplary embodiments, the second plurality of randomly oriented individual fibers may be present within the nonwoven web 110 at a weight fraction of no less than two percent (2%) and no more than twenty percent (20%) of the nonwoven web 110, for example, at a weight fraction of no less than three percent (3%) and no more than fifteen percent (15%) of the nonwoven web 110.Such concentration of the second plurality of randomly oriented individual fibers within the nonwoven web 110 may advantageously contribute to enabling the formation of a nonwoven web 110 having the significant difference in thickness between the embossed portions 112 and the bulked portions 114 of the nonwoven web 110.

[0040] As in Fig. 3, the nonwoven web 110 may also define a plurality of apertures 140. The apertures 140 may extend through a nonwoven web 110, e.g., between the first and second surfaces 102, 104 of the nonwoven web 110. The apertures may allow the passage of liquids through the nonwoven web 110, e.g., from the first surface 102 to the second surface 104 or vice versa.

[0041] The nonwoven web 110 can be used to at least partially form a product such as a diaper, disposable undergarment, incontinence pad, sanitary napkin, etc. For example, the nonwoven web 110 can be used in a diaper as an inner liner that comes into contact with the wearer's skin. The significant difference in thickness between the embossed portions 112 and the puffed portions 114 of the nonwoven web 110 can increase wearer comfort compared to known liners. For example, the distal ends of the puffed portions 114 can contact the wearer, and air can fill the gaps formed between the embossed portions 112. Additionally, liquids and other substances can flow away from the wearer through the gaps formed in the embossed portions 112 and / or openings 140.The space provided by the gaps formed at the embossed portions 112 can advantageously limit discomfort by allowing liquids and other substances to migrate away from the wearer, and / or the air in the gaps formed at the embossed portions 112 can facilitate drying of the wearer's skin. The "lofty" properties of the nonwoven web 110 can thus advantageously increase the wearer's comfort.

[0042] With reference now to Fig. 3 and Fig. Figure 4 illustrates a schematic view of an embossing apparatus 200 for a nonwoven fabric according to an exemplary embodiment of the present disclosure. Embossing apparatus 200 may be used to emboss fibrous nonwoven web 110, e.g., to form embossed portions 112 and lofted portions 114 on fibrous nonwoven web 110. However, it should be understood that in alternative exemplary embodiments, embossing apparatus 200 may be used to emboss other suitable nonwoven fabrics.

[0043] As in the Fig. 3 and Fig. 4, the embossing apparatus 200 includes a first roller 210 and a second roller 220. A nonwoven web 230 may be passed between the first and second rollers 210, 220 during operation of the embossing apparatus 200 to emboss the nonwoven web 230. The nonwoven web 230 is not embossed before the first and second rollers 210, 220 (indicated by arrow 232) and is embossed after the first and second rollers 210, 220 (indicated by arrow 234). The first and second rollers 210, 220 may rotate to move the nonwoven web 230 through the embossing apparatus 200.

[0044] As in Fig. 4, the first roller 210 may include a plurality of protrusions 212, and the second roller 220 may define a plurality of cavities 222. Each protrusion 212 of the first roller 210 may be received within a corresponding recess 222 of the second roller 220 during rotation of the first and second rollers 210, 220. The shape and arrangement of the protrusions 212 and / or recesses 222 may correspond to the shape and arrangement of embossments on the nonwoven web 230, such as embossed portions 112 and puffed portions 114 on the nonwoven web 110. The first roller 210 and / or the second roller 220 may be heated during operation of the embossing apparatus 200 to assist in forming embossments on the nonwoven web 230.

[0045] Fig. 5 illustrates a method 500 for forming a nonwoven fabric according to an exemplary embodiment of the present disclosure. As one example, the method 500 may be used to form a nonwoven fabric 100 having the properties described above for nonwoven fabric 100. Therefore, the method 500 will be described in more detail below in connection with nonwoven fabric 100. However, it should be understood that the method 500 may be used to form other nonwoven fabrics in alternative exemplary embodiments. As explained in more detail below, the use of the method 500 may advantageously provide a "lofty" nonwoven fabric.

[0046] At 510, the first plurality of randomly oriented single fibers may be mixed with the second plurality of randomly oriented single fibers. For example, with respect to the first plurality of randomly oriented single fibers, pellets of plastic (e.g., polypropylene) may be extruded through a large number of orifices in a spinneret or nozzle to form fine filaments that are quickly drawn and collected on a belt to form the first plurality of randomly oriented single fibers. Thus, the first plurality of randomly oriented single fibers may be a spunbonded fabric. As another example, with respect to the second plurality of randomly oriented single fibers, pellets of plastic (e.g.,Polypropylene) are extruded through small dies surrounded by a high-velocity blowing gas to form fine filaments that are blown onto a belt to form the second plurality of randomly oriented individual fibers. Thus, the first plurality of randomly oriented individual fibers may be meltblown. The first plurality of randomly oriented individual fibers may be intermixed with the second plurality of randomly oriented individual fibers by "dusting" the first plurality of randomly oriented individual fibers with the second plurality of randomly oriented individual fibers that are relatively smaller.

[0047] At 520, the mixture of the first and second pluralities of randomly oriented individual fibers may be bonded to form the nonwoven web 110. For example, the mixture of the first and second pluralities of randomly oriented individual fibers may be passed through a thermal bonder to form the nonwoven web 110 from the mixture of the first and second pluralities of randomly oriented individual fibers.

[0048] At 530, a portion of the nonwoven web 110 formed at 520 may be embossed. Thus, after 530, the nonwoven web 110 may include embossed portions 112 and bulked portions 114. Due to the concentration of the second plurality of randomly oriented individual fibers within the nonwoven web 110, the average gauge TU of the nonwoven web 110 at bulked portions 114 of the nonwoven web 110 may be no less than three times (3X) greater than the average gauge TE of the nonwoven web 110 at embossed portions 112 of the nonwoven web 110 after 530. It should be understood that the bonding at 520 and the embossing at 530 may be combined in a single step in certain exemplary embodiments. At 530, the speed of the nonwoven web 110 may be increased by an embossing device, e.g., a rotary embosser. B. by embossing device 200, not less than two hundred meters per second (200 m / s) and not more than one thousand meters per second (1000 m / s).Accordingly, the method 500 can advantageously form bulky embossments on the nonwoven web 110 despite a high processing speed when embossing the nonwoven web 110.

[0049] Fig. For the purpose of illustration and explanation, Figure 5 shows steps performed in a particular order. Those of ordinary skill in the art, using the disclosures provided herein, will understand that the steps of any of the methods explained herein may be variously adapted, rearranged, expanded, omitted, or modified without departing from the scope of the present disclosure.

[0050] Fig. 6 is a scan 600 of a nonwoven fabric according to an exemplary embodiment of the present disclosure. Furthermore, Fig. 6 is an image of a nonwoven fabric under a scanning electron microscope according to an exemplary embodiment of the present disclosure. The exemplary nonwoven fabric shown in scan 600 was formed according to method 500. As in Fig. As shown in Figure 6, the nonwoven fabric contains various embossings, which are the darker circles within the nonwoven fabric. Measurements of the thickness of the nonwoven fabric were taken along line 610 in Fig. 6. Fig. Figure 7 is a graphical representation of the thickness of the nonwoven fabric along line 610. As shown, the thickness of the nonwoven fabric increases and decreases between adjacent embossings. Furthermore, a maximum measured thickness of the nonwoven fabric was approximately two thousand micrometers (2000 µm) and a minimum measured thickness of the nonwoven fabric was approximately one hundred and eleven micrometers (111 µm). Thus, the exemplary nonwoven fabric advantageously exhibits "loft" properties despite the embossing at high speeds.

[0051] Here, the diameter of the fibers in a sample of a nonwoven web can be determined using a scanning electron microscope (SEM) and image analysis software. A magnification of five hundred (500) to ten thousand (10,000) can be selected so that the fibers are suitably magnified for measurement. The samples can be sputtered with gold or a palladium compound to prevent electrical charging and vibration of the fibers in the electron beam. A manual method can be used to determine fiber diameters. Using a mouse and a cursor tool, the edge of a randomly selected fiber can be located and then measured across the width of the fiber (i.e., perpendicular to the fiber direction at that point) to the other edge of the fiber. A scaled and calibrated image analysis tool can provide the scaling to obtain actual measurements in micrometers (µm).Therefore, using the SEM, multiple fibers can be randomly selected across the nonwoven web sample. In this way, at least two samples from the nonwoven web (or the nonwoven web within a product) can be cut and tested. A total of at least one hundred (100) such measurements can be taken, and then all data can be recorded for statistical analysis. The recorded data can be used to calculate the mean fiber diameter, the standard deviation of the fiber diameter, and the mean fiber diameter. Another useful statistic is the calculation of the amount of the fiber population that is below a certain upper limit.To determine this statistic, the software is programmed to count how many fiber diameter results are below an upper limit, and this count (divided by the total number of data and multiplied by 100%) is expressed as a percentage below the upper limit, for example, as a percentage below one micron diameter or in % submicron.

[0052] The strength of a sample of a nonwoven web can be determined using a scanning electron microscope (SEM) and image analysis software, as described above in the Fig. 6 and Fig.7. A magnification of five hundred (500) to ten thousand (10,000) can be selected so that the nonwoven web is suitably magnified for measurement. The sample can be sputtered with gold or a palladium compound to prevent electrical charging and vibration of the nonwoven web fibers in the electron beam. A manual method can be used to determine the web thickness. Using a mouse and cursor tool, a line can be searched for across a randomly selected section of the web, and then the web thickness can be measured along the line, e.g., from a base on which the web is placed to a nearest surface of the web. A scaled and calibrated image analysis tool can provide the scaling to obtain actual measurements in micrometers (µm).Thus, using the SEM, multiple sections of the web can be randomly selected throughout the sample web. In this way, at least two samples can be cut and tested from the nonwoven web (or the nonwoven web within a product). A total of at least one hundred (100) such measurements can be taken, and then all data can be recorded for statistical analysis. The recorded data can be used to calculate the mean web thickness, the standard deviation of the web thickness, and the mean web thickness. Another useful statistic is the calculation of the proportion of measured web thicknesses in the sample web that are below a certain upper limit.

[0053] To determine this statistic, the software is programmed to count how many gauge results are below an upper limit, and this count (divided by the total number of data and multiplied by 100%) is expressed as a percentage below the upper limit, for example, as a percentage below one micron diameter or in % submicron.

[0054] The repeated use of reference numerals in this specification and the drawings is intended to represent the same or analogous features or elements of the present invention.

[0055] These and other modifications and variations of the present invention may be made by one skilled in the art without departing from the spirit and scope of the present invention, as particularly pointed out in the appended claims. Furthermore, it is to be understood that aspects of the various embodiments are interchangeable, in whole or in part. Furthermore, those skilled in the art will understand that the foregoing description is merely exemplary and is not intended to limit the invention, as particularly described in the appended claims. REFERENCE SYMBOL 100 nonwoven fabric 102 First area 104 Second area 105 First final section 106 Second final section 107 First page section 108 Second page section 110 nonwoven web 112 embossed sections 114 Bulged Sections 116 peaks 118 floors 120 First Row 122 Second Row 124 Third Row 130 First column 132 Second column 134 Third column 140 openings 200 embossing device 210 First roller 212 projections 220 Second roller 222 cavities 500 procedures 510 steps 520 steps 530 steps 600 scans 700 Graphic representation EXEMPLARY EMBODIMENTS

[0056] First exemplary embodiment: A nonwoven fabric comprising a first plurality of randomly oriented individual fibers and a second plurality of randomly oriented individual fibers that together form a nonwoven fibrous web. A ratio of an average diameter of the first plurality of randomly oriented individual fibers to an average diameter of the second plurality of randomly oriented individual fibers is between 50:1 and 3:1. The first plurality of randomly oriented individual fibers are present within the nonwoven fibrous web in an amount of no less than 70% by weight of the nonwoven fibrous web. The second plurality of randomly oriented individual fibers are present within the nonwoven fibrous web in an amount of no less than 2% by weight of the nonwoven fibrous web and no more than 20% by weight of the nonwoven fibrous web. A portion of the nonwoven fibrous web is embossed.

[0057] Second exemplary embodiment: The embossed nonwoven fabric of the first exemplary embodiment, wherein the first plurality of randomly oriented single fibers are polypropylene fibers and the second plurality of randomly oriented single fibers are polypropylene fibers.

[0058] Third exemplary embodiment: An embossed nonwoven fabric of either the first exemplary embodiment or the second exemplary embodiment, wherein the first plurality of randomly oriented individual fibers are spunbonded polypropylene fibers and the second plurality of randomly oriented individual fibers are meltblown polypropylene fibers.

[0059] Fourth exemplary embodiment: The embossed nonwoven fabric of any of the first to third exemplary embodiments, wherein: the average diameter of the first plurality of randomly oriented single fibers is not less than ten micrometers and not more than twenty-two micrometers; and the average diameter of the second plurality of randomly oriented single fibers is not less than half a micrometer and not more than three micrometers.

[0060] Fifth exemplary embodiment: The embossed nonwoven fabric of any of the first to fourth exemplary embodiments, wherein: the average diameter of the first plurality of randomly oriented individual fibers is not less than twelve micrometers and not more than eighteen micrometers; and the average diameter of the second plurality of randomly oriented individual fibers is not less than seven-tenths of a micrometer and not more than two micrometers.

[0061] Sixth exemplary embodiment: The embossed nonwoven fabric of any of the first to fifth exemplary embodiments, wherein an average thickness of the nonwoven fibrous web in an unembossed portion of the nonwoven fibrous web is not less than three times greater than an average thickness of the nonwoven fibrous web in the embossed portion of the nonwoven fibrous web.

[0062] Seventh exemplary embodiment: The embossed nonwoven fabric of any of the first to sixth exemplary embodiments, wherein the average thickness of the nonwoven fibrous web in the unembossed portion of the nonwoven fibrous web is not less than five times greater than the average thickness of the nonwoven fibrous web in the embossed portion of the nonwoven fibrous web.

[0063] Eighth exemplary embodiment: The embossed nonwoven fabric of any of the first to seventh exemplary embodiments, wherein: the average thickness of the nonwoven fibrous web in the unembossed portion of the nonwoven fibrous web is not less than one hundred micrometers and not more than about three hundred micrometers; and the average thickness of the nonwoven fibrous web in the embossed portion of the nonwoven fibrous web is not less than five hundred micrometers and not more than three thousand micrometers.

[0064] Ninth exemplary embodiment: The embossed nonwoven fabric of any of the first to eighth exemplary embodiments, wherein the nonwoven fibrous web defines a plurality of apertures extending through a thickness of the nonwoven fibrous web.

[0065] Tenth exemplary embodiment: A product comprising the embossed nonwoven fabric of any one of the first to ninth exemplary embodiments, the product being a diaper, a disposable undergarment, an incontinence pad, and a sanitary napkin.

[0066] Eleventh exemplary embodiment: A nonwoven fabric comprising a plurality of randomly oriented individual spunbonded polypropylene fibers and a plurality of randomly oriented individual meltblown polypropylene fibers together forming a nonwoven web. A ratio of an average diameter of the plurality of randomly oriented individual spunbonded polypropylene fibers to an average diameter of the plurality of randomly oriented individual meltblown polypropylene fibers is between 60:1 and 2:1. The plurality of randomly oriented individual spunbonded polypropylene fibers are present within the nonwoven web at no less than 70% by weight of the nonwoven web. The plurality of randomly oriented individual meltblown polypropylene fibers within the nonwoven web are present in an amount of no less than 2% by weight of the nonwoven web and no more than 20% by weight of the nonwoven web.A portion of the nonwoven web is embossed such that the average thickness of the nonwoven web in an unembossed portion of the nonwoven web is not less than three times greater than the average thickness of the nonwoven web in the embossed portion of the nonwoven web.

[0067] Twelfth Exemplary Embodiment: The embossed nonwoven fabric of the eleventh exemplary embodiment, wherein: the average diameter of the plurality of randomly oriented individual spunbond polypropylene fibers is not less than ten micrometers and not more than twenty-two micrometers; and the average diameter of the plurality of randomly oriented individual meltblown polypropylene fibers is not less than half a micrometer and not more than three micrometers.

[0068] Thirteenth exemplary embodiment: The embossed nonwoven fabric of either the eleventh exemplary embodiment or the twelfth exemplary embodiment, wherein: the average diameter of the plurality of randomly oriented individual spunbond polypropylene fibers is not less than twelve micrometers and not more than eighteen micrometers; and the average diameter of the plurality of randomly oriented individual meltblown polypropylene fibers is not less than seven-tenths of a micrometer and not more than two micrometers.

[0069] Fourteenth exemplary embodiment: The embossed nonwoven fabric of any of the eleventh to thirteenth exemplary embodiments, wherein the average thickness of the nonwoven fibrous web in the unembossed portion of the nonwoven fibrous web is not less than five times greater than the average thickness of the nonwoven fibrous web in the embossed portion of the nonwoven fibrous web.

[0070] Fifteenth exemplary embodiment: The embossed nonwoven fabric of any of the eleventh to fourteenth exemplary embodiments, wherein: the average thickness of the nonwoven fibrous web in the unembossed portion of the nonwoven fibrous web is not less than one hundred micrometers and not more than about three hundred micrometers; and the average thickness of the nonwoven fibrous web in the embossed portion of the nonwoven fibrous web is not less than five hundred micrometers and not more than three thousand micrometers.

[0071] Sixteenth exemplary embodiment: The embossed nonwoven fabric of any of the eleventh to fifteenth exemplary embodiments, wherein the nonwoven fibrous web defines a plurality of apertures extending through a thickness of the nonwoven fibrous web.

[0072] Seventeenth exemplary embodiment: A method of forming an embossed nonwoven fabric comprising: bonding a blend of a plurality of randomly oriented individual spunbonded polypropylene fibers and a plurality of randomly oriented individual meltblown polypropylene fibers to form a fibrous nonwoven web, wherein the plurality of randomly oriented individual spunbonded polypropylene fibers are present within the blend at no less than seventy percent by weight of the blend, wherein the plurality of randomly oriented individual meltblown polypropylene fibers are present within the blend at no less than two percent by weight of the blend and no more than twenty percent by weight of the blend;and embossing a portion of the nonwoven web such that an average thickness of the nonwoven web in an unembossed portion of the nonwoven web is not less than three times greater than an average thickness of the nonwoven web in the embossed portion of the nonwoven web;

[0073] Eighteenth exemplary embodiment: The method of the seventeenth exemplary embodiment, wherein the speed of the nonwoven web during embossing is not less than two hundred meters per second and not more than one thousand meters per second.

[0074] Nineteenth exemplary embodiment: The method of either the seventeenth exemplary embodiment or the eighteenth exemplary embodiment, wherein the ratio of the average diameter of the plurality of randomly oriented individual spunbond polypropylene fibers to the average diameter of the plurality of randomly oriented individual meltblown polypropylene fibers is between 50:1 and 3:1.

Claims

[1] Nonwoven fabric comprising: a first plurality of randomly oriented individual fibers and a second plurality of randomly oriented individual fibers mixed and bonded together to form a nonwoven web, wherein a ratio of an average diameter of the first plurality of randomly oriented individual fibers to an average diameter of the second plurality of randomly oriented individual fibers is between 50:1 and 3:1, wherein the first plurality of randomly oriented individual fibers are present within the nonwoven web in a proportion of not less than seventy percent by weight of the nonwoven web, wherein the second plurality of randomly oriented individual fibers are present in the nonwoven web in an amount of not less than two percent by weight of the nonwoven web and not more than twenty percent by weight of the nonwoven web, and wherein a section of the nonwoven web is embossed. [2] The nonwoven fabric of claim 1, wherein the first plurality of randomly oriented single fibers are polypropylene fibers and the second plurality of randomly oriented single fibers are polypropylene fibers. [3] The nonwoven fabric of claim 1, wherein the first plurality of randomly oriented individual fibers are spunbonded polypropylene fibers and the second plurality of randomly oriented individual fibers are meltblown polypropylene fibers. [4] Nonwoven fabric according to claim 1, wherein: the average diameter of the first plurality of randomly aligned individual fibers is not less than ten micrometers and not more than twenty-two micrometers; and the average diameter of the second plurality of randomly aligned individual fibers is not less than half a micrometer and not more than three micrometers. [5] Nonwoven fabric according to claim 1, wherein: the average diameter of the first plurality of randomly aligned individual fibers is not less than twelve micrometers and not more than eighteen micrometers; and the average diameter of the second plurality of randomly aligned individual fibers is not less than seven-tenths of a micrometer and not more than two micrometers. [6] The nonwoven fabric according to claim 1, wherein an average thickness of the nonwoven web in an unembossed portion of the nonwoven web is not less than three times greater than an average thickness of the nonwoven web in the embossed portion of the nonwoven web. [7] The nonwoven fabric of claim 6, wherein the average thickness of the nonwoven web in the unembossed portion of the nonwoven web is not less than five times greater than the average thickness of the nonwoven web in the embossed portion of the nonwoven web. [8] Nonwoven fabric according to claim 6, wherein: the average thickness of the nonwoven web in the unembossed portion of the nonwoven web is not less than 100 micrometers and not more than about 300 micrometers; and the average thickness of the nonwoven web in the embossed portion of the nonwoven web is not less than five hundred micrometers and not more than three thousand micrometers. [9] The nonwoven fabric of claim 1, wherein the nonwoven fibrous web defines a plurality of apertures extending through a thickness of the nonwoven fibrous web. [10] A product comprising the embossed nonwoven fabric according to claim 1, wherein the product is a diaper, a disposable undergarment, an incontinence pad or a sanitary napkin. [11] Nonwoven fabric comprising: a plurality of randomly oriented individual spunbonded polypropylene fibers and a plurality of randomly oriented individual meltblown polypropylene fibers blended and bonded together to form a nonwoven web, wherein a ratio of an average diameter of the plurality of randomly oriented individual spunbonded polypropylene fibers to an average diameter of the plurality of randomly oriented individual meltblown polypropylene fibers is between 60:1 and 2:1, wherein the plurality of randomly oriented, individual spunbond polypropylene fibers within the nonwoven web are present in not less than seventy percent by weight of the nonwoven web, wherein the plurality of randomly oriented individual meltblown polypropylene fibers are present in the nonwoven web in an amount of not less than two percent by weight of the nonwoven web and not more than twenty percent by weight of the nonwoven web, and wherein a portion of the nonwoven web is embossed such that the average thickness of the nonwoven web in an unembossed portion of the nonwoven web is not less than three times greater than the average thickness of the nonwoven web in the embossed portion of the nonwoven web. [12] Nonwoven fabric according to claim 11, wherein: the average diameter of the plurality of randomly oriented individual spunbonded polypropylene fibers is not less than ten micrometers and not more than twenty-two micrometers; and the average diameter of the plurality of randomly oriented individual meltblown polypropylene fibers is not less than half a micrometer and not more than three micrometers. [13] Nonwoven fabric according to claim 11, wherein: the average diameter of the plurality of randomly oriented individual spunbond polypropylene fibers is not less than twelve micrometers and not more than eighteen micrometers; and the average diameter of the plurality of randomly oriented individual meltblown polypropylene fibers is not less than seven-tenths of a micrometer and not more than two micrometers. [14] The nonwoven fabric of claim 11, wherein the average thickness of the nonwoven web in the unembossed portion of the nonwoven web is not less than five times greater than the average thickness of the nonwoven web in the embossed portion of the nonwoven web. [15] Nonwoven fabric according to claim 11, wherein: the average thickness of the nonwoven web in the unembossed portion of the nonwoven web is not less than 100 micrometers and not more than about 300 micrometers; and the average thickness of the nonwoven web in the embossed portion of the nonwoven web is not less than five hundred micrometers and not more than three thousand micrometers. [16] The nonwoven fabric of claim 11, wherein the nonwoven fibrous web defines a plurality of apertures extending through a thickness of the nonwoven fibrous web. [17] A method of forming an embossed nonwoven fabric comprising: Bonding a blend of a plurality of randomly oriented individual spunbonded polypropylene fibers and a plurality of randomly oriented individual meltblown polypropylene fibers to form a nonwoven web, wherein the plurality of randomly oriented individual spunbonded polypropylene fibers are present within the blend at not less than seventy percent by weight of the blend, wherein the plurality of randomly oriented individual meltblown polypropylene fibers are present within the blend at not less than two percent by weight of the blend and not more than twenty percent by weight of the blend; and Embossing a portion of the nonwoven web such that an average thickness of the nonwoven web in an unembossed portion of the nonwoven web is not less than three times greater than an average thickness of the nonwoven web in the embossed portion of the nonwoven web. [18] The method of claim 17, wherein the speed of the nonwoven web during embossing is not less than two hundred meters per second and not more than one thousand meters per second. [19] The method of claim 17, wherein a ratio of the average diameter of the plurality of randomly oriented individual spunbond polypropylene fibers to the average diameter of the plurality of randomly oriented individual meltblown polypropylene fibers is between 50:1 and 3:1.

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