Patent Application
20170319397
The present invention relates to disposable pull-on garments comprising elastics in the crotch region.
The present specification discloses disposable absorbent articles comprising central panels (also referred to as central chassis or center chassis or main body) comprising absorbent cores. The absorbent articles may also comprise graphics. The disclosed designs of articles herein may be worn by all ages, including infants, toddlers, children, as well as adults.
It may be desirable to run elastics continuously across the core and/or central panel to decrease the appearance of the core and central panel area, which may help the absorbent article to appear more underwear like. This may be especially important for adult wearers. Running elastics continuously across the core and/or central panel may create too much tension in force zones and/or elastic sections causing the crotch area and areas adjacent to the crotch area to pull in transversely (i.e., too narrow).
Due to this, absorbent articles are often designed with elastics that are cut so they do not run across or continuously across the core or the central panel. Elastics cut in this manner may provide more coverage over the buttocks versus a product with elastics running continuously across the core and/or central panel. Of course, adequate coverage is desired for fit. Beyond fit, for adult incontinence products, adequate coverage is desired to provide comfort and security. Too much tension of a long continuous elastic can cause the portion of the belt adjacent to the transverse axis to narrow and ride up higher on the wearer's back-side compromising fit and causing discomfort.
Instead of cutting elastics to prevent the negatives of continuous elastics across the core and/or central panel, it may be desirable to space out elastics (i.e., decrease the number of elastics per area) in the force zones and/or elastic sections adjacent to the transverse centerline of the article. Thus, the area at and just above the leg cutout can benefit from spaced out elastics to keep tension from being too concentrated, thus causing narrowing of the front and back panels adjacent to the crotch. This is especially problematic in the back panel where it compromises buttocks coverage. With spaced out elastics, the average tension of the elastic zone and/or section is decreased.
One way to decrease the number of elastics per unit area is to create larger spaces between evenly, more tightly spaced elastics. Many elastic profiles of the present disclosure decrease the number of elastics per unit area by gradually increasing the space between elastics approaching the transverse centerline.
Additionally, it may also be desirable to create a larger area void of elastics on each side of the transverse axis for a certain area, which may simplify the process of making a multi-stranded elastic absorbent article because it creates a larger area without elastics. Elastics in this area may also be seen as unnecessary as the product at the center area of the crotch region is forced inwards by the wearer's thighs. Further, elastics in this region could overly narrow the crotch region such that gasketing is compromised. This may be especially true for articles comprising leg cuffs because the cuff path may be distorted by the lateral forces over the crotch region. Thus, this disclosure suggests desirable areas above and below the transverse centerline that may be free from transversely disposed elastics.
The disclosure also recognizes that gradual spacing changes of the elastic profile may be more aesthetically appealing versus cutting the elastics or providing large gaps throughout a profile.
While the specification concludes with claims particularly pointing out and distinctly claiming the subject matter which is regarded as forming the present invention, it is believed that the invention will be better understood from the following description which is taken in conjunction with the accompanying drawings in which like designations are used to designate substantially identical elements, and in which:
As used herein, the term “pull-on garment” refers to articles of wear which have a defined waist opening and a pair of leg openings and which are pulled onto the body of the wearer by inserting the legs into the leg openings and pulling the article up over the waist. The term “disposable” is used herein to describe garments which are not intended to be laundered or otherwise restored or reused as a garment (i.e., they are intended to be discarded after a single use and, preferably, to be recycled, composted or otherwise disposed of in an environmentally compatible manner). The pull-on garment is also preferably “absorbent” to absorb and contain the various exudates discharged from the body. A preferred embodiment of the absorbent article is the disposable absorbent pull-on garment, shown in
As used herein, the term “absorbent article” refers to pull-on garments generally worn by infants and other incontinent individuals to absorb and contain urine, feces and/or menses. It should be understood, however, that the term absorbent article is also applicable to other garments such as training pants, incontinent briefs, feminine hygiene garments or panties, and the like.
As used herein, the terms “elastic,” “elastomer,” and “elastomeric” refer to a material which generally is able to extend to a strain of at least 50% without breaking or rupturing, and is able to recover substantially to its original dimensions, accounting for set, after the deforming force has been removed.
As used herein, the term “joined” encompasses configurations whereby an element is directly secured to another element by affixing the element directly to the other element, and configurations whereby an element is indirectly secured to another element by affixing the element to intermediate member(s) which in turn are affixed to the other element.
The absorbent article 20 has an outer surface 22, an inner surface 24 opposed to the outer surface 22, a front region 26, a back region 28, a crotch region 30, and seams 32 which join the front region 26 and the back region 28 to form two leg openings 34 and a waist opening 36. Also referring to
In the embodiment shown in
As shown in
The absorbent main body 38 absorbs and contains body exudates disposed on the main body 38. The absorbent main body also comprises left and right longitudinally extending side edges 48 (hereinafter may be referred to as “longitudinal side edge”) and front and back transversely extending end edges 50 (hereinafter may be referred to as “transverse end edge”).
As shown in
As shown in
The absorbent article may comprise curved leg elastics that run parallel to, and a few millimeters inboard of, at least a portion of the leg cut outs.
A portion or the whole of the main body 38 may be made extensible to a degree greater than the inherent extensibility of the material or materials from which the main body 38 is made, e.g., the backsheet 60. The additional extensibility may be desirable in order to allow the main body 38 to conform to the body of a wearer during movement by the wearer and or to provide adequate body coverage. The additional extensibility may also be desirable, for example, in order to allow the user of an absorbent article including a main body 38 having a particular size before extension to extend the front waist region 26, the back waist region 28, or both waist regions of the main body 38 to provide additional body coverage for wearers of differing size, i.e., to tailor the article to the individual wearer. Such extension of the waist region or regions may give the main body 38 a generally hourglass shape, so long as the crotch region is extended to a relatively lesser degree than the waist region or regions, and may impart a tailored appearance to the article when it is worn. In addition, the additional extensibility may be desirable in order to minimize the cost of the article 10. For example, an amount of material that would otherwise be sufficient only to make a relatively smaller article lacking this extensibility can be used to make an article capable of being extended to adequately cover a wearer that is larger than the unextended smaller absorbent article would fit.
A portion of the main body 38, for example, a portion of the chassis in one or both of the waist regions 26, 28 may be made laterally extensible to a maximum extensibility greater than a maximum extensibility of another portion of the main body 38 in the crotch region such that a lateral extension of each of the portions to its maximum extensibility imparts an hourglass shape to the main body 38. In one embodiment, the portion of the main body 38 underlying and/or immediately adjacent one or both of the front and back extensible belts may be made laterally extensible to a maximum extensibility greater than a maximum extensibility of another portion of the main body 38, for example the crotch region, such that a lateral extension of each of the portions to its maximum extensibility facilitates application of the absorbent article onto the body of a wearer by enabling the waist regions to be extended to fit over the wearer's hips and in addition, opening and orienting the leg openings enabling the wearer to place the legs through the openings more effectively.
Additional lateral extensibility in the main body 38 may be provided in a variety of ways. For example, a material or materials from which the main body 38 is made may be pleated by any of many known methods. Alternatively, all or a portion of the main body 38 may be made of a formed web material or a formed laminate of web materials like those described in U.S. Pat. No. 5,518,801 (herein “Chappell et al.,” issued on May 21, 1996). This formed web material includes distinct laterally extending regions in which the original material has been altered by embossing or another method of deformation to create a pattern of generally longitudinally oriented alternating ridges and valleys and also includes laterally extending unaltered regions between the laterally extending altered regions. The formed web material can be extended in a direction perpendicular to the ridges up to the point where the ridges and valleys flatten with substantially less force than is required to extend beyond that point. In addition to lateral extensibility, the creation of a formed laminate web as described above provides a main body 38 backsheet with improved texture and cloth-like appearance and feel. The deformation creates a cloth-like pattern in the film and increases the loft of the nonwoven in multi-layer film and nonwoven laminate backsheets.
Alternatively, a portion of the absorbent article can be ring-rolled and thus rendered highly extensible as described in U.S. Pat. No. 5,366,782 (herein “Curro et al.,” issued on Nov. 22, 1994). Specifically, a ring-rolling apparatus includes opposing rolls having intermeshing teeth that incrementally stretch and thereby plastically deform the material forming the absorbent article (or a portion thereof) thereby rendering the article extensible in the ring-rolled regions. In one embodiment, the absorbent article can be ring-rolled in a portion of at least one of the front or back waist regions, for example the portion of the main body 38 underlying and/or immediately adjacent one or both of the front and back belts 84, 86, while other regions may comprise a structured elastic-like formed web material. The article may be ring-rolled across the entire width in one or both of the waist regions or alternatively may be ring-rolled over only a portion of the main body 38 width or over only a portion of one or both of the belts.
The front laterally central portion and the back laterally central portion of the main body 38 may have a different range of extensibility from other portions of the main body 38. Additionally or alternatively, the laterally central portions may be extensible to a greater or lesser degree when subjected to a given level of opposing tensile forces, i.e., may be more easily or less easily extensible, than other portions of the main body 38.
The main body 38 may comprise a liquid pervious topsheet 58, a liquid impervious backsheet 60 and an absorbent core 62 disposed therebetween. The main body 38 may additionally comprise a barrier leg cuff 64 disposed along the longitudinal side edge 48. The barrier leg cuff 64 provides improved containment of liquids and other body exudates in the crotch region 30. The barrier leg cuff 64 shown in
As shown in
As shown in
The liquid pervious topsheet 58 may be positioned adjacent the body-facing surface of the absorbent core 62 and may be joined thereto and/or to the backsheet 60 by any attachment means known in the art. The liquid impervious backsheet 60 is generally that portion of the absorbent article 20 positioned adjacent the garment-facing surface of the absorbent core 62 and prevents the exudates absorbed and contained therein from soiling articles that may contact the absorbent article 20. The absorbent core is positioned between the topsheet 58 and the backsheet 60 and absorbs and retains liquids such as urine and other certain body exudates.
The topsheet 58, the backsheet 60 and the absorbent core may be manufactured known materials. Suitable topsheet materials may include porous foams; reticulated foams; apertured plastic films; or woven or nonwoven webs of natural fibers (e.g., wood or cotton fibers), synthetic fibers (e.g., polyester or polypropylene fibers), or a combination of natural and synthetic fibers. Suitable backsheet materials may include breathable materials that permit vapors to escape from the diaper while still preventing exudates from passing through the backsheet.
A suitable absorbent core for use in the absorbent article 20 may comprise any absorbent material which is generally compressible, conformable, non-irritating to the wearer's skin, and capable of absorbing and retaining liquids such as urine and other certain body exudates. In addition, the configuration and construction of the absorbent core may also be varied (e.g., the absorbent core(s) or other absorbent structure(s) may have varying caliper zones, hydrophilic gradient(s), a superabsorbent gradient(s), or lower average density and lower average basis weight acquisition zones; or may comprise one or more layers or structures). In some embodiments, the absorbent core may comprise a fluid acquisition component, a fluid distribution component, and a fluid storage component. An example of a suitable absorbent core having a fluid acquisition component, a fluid distribution component, and a fluid storage component is described in U.S. Pat. No. 6,590,136 (herein “Young et al.,” granted on Jul. 8, 2003).
Suitable absorbent cores of the present disclosure may comprise cellulosic airfelt material. For instance, such absorbent cores may comprise less than about 40%, 30%, 20%, 10%, 5%, or even 1% of the cellulosic airfelt material as determined by weight. Additionally, such an absorbent core may be primarily comprised of an absorbent gelling material in amounts of at least about 60%, 70%, 80%, 85%, 90%, 95%, or even about 100% as determined by weight. Furthermore, a portion of the absorbent core may comprise a microfiber glue (if applicable). Such absorbent cores, microfiber glues, and absorbent gelling materials are described in U.S. Pat. No. 5,599,335 (herein “Goldman et al.,” granted Feb. 4, 1997); U.S. Pat. No. 5,562,646 (herein “Goldman et al.,” granted Oct. 8, 1996); U.S. Pat. No. 5,669,894 (herein “Goldman et al.,” granted Sep. 23, 1997); U.S. Pat. No. 6,790,798 (herein “Suzuki et al.,” granted Sep. 14, 2004); U.S. Pat. No. 521,587 (herein “Busam et al.,” granted Apr. 21, 2009); and in U.S. Patent Pub. No. 2004/0158212 (herein “Ponomarenko et al.,” published Aug. 12, 2004).
The absorbent core, including multiple layers making up the core system, may be printed and embossed as described in U.S. Pat. No. 8,536,401 (herein “Ecker et al.,” granted on Sep. 17, 2013).
The absorbent core may be separable from the chassis as disclosed in U.S. Pat. No. 6,989,006 (herein “LaVon et al.,” granted on Jan. 24, 2006; U.S. Pat. No. 7,381,202 (herein “LaVon et al.,” granted on Jun. 3, 2008; U.S. Pat. No. 7,175,613 (herein “Sugiyama et al.,” granted on Feb. 13, 2007; U.S. Pat. No. 7,824,386 (herein “LaVon et al.,” granted on Nov. 2, 2010; U.S. Pat. No. 7,766,887 (herein “Burns et al.,” granted on Aug. 3, 2010; and U.S. Pat. No. 6,989,005 (herein “LaVon et al.,” granted on Jan. 24, 2006. In such embodiments, the measurements described in this disclosure may be made to the chassis alone or may be made to the chassis in combination with the separable core/absorbent assembly.
The absorbent article of the present disclosure, and particularly, a portion where the absorbent core is disposed, may have a body fluid absorption rate greater than 3 g/sec according to U.S. Pat. No. 6,649,810 (herein “Minato et al.,” granted on Nov. 18, 2003). According to U.S. Pat. No. 6,649,810 (herein “Minato et al.,” granted on Nov. 18, 2003), the expression “the portion (of the absorbent article) where the absorbent member is disposed” is intended to mean the portion occupied by the absorbent member when the absorbent article is flatly unfolded and seen in its plan view.
The absorbent core may have an intake factor greater than 3 according to U.S. Pat. No. 7,073,373 (herein “La Fortune,” granted Jul. 11, 2006), wherein the intake factor is defined as the absorbent core permeability divided by the normalized retention capacity (which is defined by the Retention Capacity Test—also according to U.S. Pat. No. 7,073,373 (herein “La Fortune,” granted Jul. 11, 2006)).
The absorbent core may have a body fluid absorption greater than 75 g/100 cm2, according to U.S. Pat. No. 6,649,810 (herein “Minato et al.,” granted on Nov. 18, 2003).
A target location of the absorbent article may have a wicking value greater than 36%, according to U.S. Pat. No. 6,383,960 (herein “Everett et al.,” granted on May 7, 2002).
The absorbent article may have a bending stiffness between 0.05-1.0 gf, according to U.S. Pat. No. 5,810,796 (herein “Kimura et al.,” granted on Sep. 22, 1998).
The absorbent article may have a crotch fluid absorption rate greater than 3 g/sec according to U.S. Pat. No. 6,649,810 (herein “Minato et al.,” granted on Nov. 18, 2003). In one embodiment, a freeze-dried composite of the absorbent composite may have an intake rate of at least about 1.9 cubic centimeters (cc) of liquid/second at 80% composite saturation according to U.S. Pat. No. 6,689,934 (herein “Dodge et al.,” granted on Feb. 10, 2004).
The absorbent core 200 may comprise channels as described in U.S. Pat. No. 8,568,566 (herein Jackels et al.,” granted on Oct. 29, 2013; U.S. Pub. No. 2012/316046 (herein “Jackels et al.,” published on Dec. 13, 2012; U.S. Pub. No. 2014/027066; U.S. Pat. No. 8,979,815 (herein “Roe et al.,” granted on Mar. 17, 2015); U.S. Pat. No. 9,216,118 (herein “Roe et al.,” granted on Dec. 22, 2015); U.S. Pat. No. 9,216,116 (herein “Roe et al.,” granted on Dec. 22, 2015); U.S. Pub. No. 2012/316526 (herein “Rosati et al.,” published on Dec. 13, 2012); U.S. Pub. No. 2012/316527 (herein “Rosati et al.,” published on Dec. 13, 2012); U.S. Pub. No. 2012/316528 (herein “Kreuzer et al.,” published on Dec. 13, 2012); U.S. Pub. No. 2012/316529 (herein “Kreuzer et al.,” published on Dec. 13, 2012); U.S. Pub. No. 2012/316523 (herein “Hippe et al.,” published on Jun. 30, 2015); U.S. Pub. No. 2014/163501 (herein “Ehrnsperger et al.,” published on Jun. 12, 2014); U.S. Pub. No. 2014/163502 (herein “Arizti et al.,” published on Jun. 12, 2014); U.S. Pub. No. 2014/163503 (herein “Arizti et al.,” published on Jun. 12, 2014); and European Pub. Nos. 2532328, 2532329, 2717823, 2717820, 2717821, 2717822, 2532332, 2740449, and 2740452.
The outer cover layer 42 may be disposed on the outer surface 22 of the absorbent article 20 and may cover the crotch panel 56 of the absorbent main body 38. The outer cover layer 42 may extend into and cover the front waist panel 52 and the back waist panel 54 of the main body 38. The outer cover layer may form a portion of the backsheet and/or the main body. The outer cover layer 42 may be directly joined to and cover a portion or all of the liquid impervious backsheet 60 of the main body 38. The central panel 80 of the front and back belt 84, 86 may be joined to the front waist panel 52 and the back waist panel 54 of the main body 38 through the outer cover layer 42. Thus, the outer cover layer 42 may be disposed between the front and back belt 84, 86 and the liquid impervious backsheet 60 of the main body 38. In one embodiment, the outer cover layer 42 may be coextensive with the liquid impervious backsheet 60. The leg elastic material 140 is disposed so as to extend generally longitudinally along the longitudinal side edge 48 of the main body 38. The leg elastic material 140 may be disposed at least in the crotch region 30 of the absorbent article 20 or may be disposed along the entirety of the longitudinal side edge 48.
The outer cover layer 42 may comprise a material separate from the material of the inner layer 83 and the outer layer 82 constituting the belt 40. The outer cover layer 42 may comprise two or more layers of materials. The outer cover layer 42 may comprise any known materials and may comprise materials used for the front and back belt 84, 86 as explained above. The outer cover layer 42 may comprise a single layer of nonwoven web of synthetic fibers. The outer cover layer 42 may comprise a single layer of hydrophobic, non-stretchable nonwoven material. The outer cover layer may comprise a film, a foam, a nonwoven, a woven material or the like and/or combinations thereof such as a laminate of a film and a nonwoven.
The belt 40 may comprise a front belt 84 and a back belt 86 (hereinafter may be referred to as “front and back belt 84, 86”) and has a ring-like configuration by permanently or refastenably connecting the front belt 84 and the back belt 86 at the seams 32 or by permanently or refastenably connecting the front and/or back belt to the main body 38. The back belt may have a greater longitudinal extent than the front belt in the seam region such that the back belt has an appendix region 500 (see
The belt 40 may be ring-like and elastic. The ring-like elastic belt 40 extends transversely about the waist opening 36 of the absorbent article 20 and acts to dynamically create fitment forces and to distribute the forces dynamically generated during wear. Applicants have found that improved fit can be created by controlling the distance between, linear density, and the pre-strain of the elastomeric material in relation to each other and to the openings for the body. This may occur by choosing different materials throughout the belt 40 that exhibit desired properties. The different materials are combined at specific distances, linear densities, and prestrains to create a belt 40 that acts to dynamically create fitment forces. This improved fit translates into reduced sagging and or gapping problems around the waist opening. The examples below illustrate various properties of the different portions of the belt embodiments that are suitable:
The data in the example tables below is hypothetical and based on the Test Methods Section described in this application for i) Average Elastic Spacing, S, ii) Average Dtex, Dt, iii) Average pre-strain, PS, and iv) Average Force at 50% strain, F50. Each of Examples 1-3 illustrate inventive pant-type disposable absorbent articles:
Each of the elastics in the front and back belts, as well as the crotch region, may have the same dtex, Dt, (e.g., Boo) and the same pre-strain, PS, (e.g., 120%). Another suitable embodiment may have each of the elastics of the front and back belts at 470 dtex at about 120 to 150% strain, with lower dtex (smaller diameter of strands) and/or lower pre-strain (less pre-strain) in the front and/or back regions of the crotch region. The front and back belt 84, 86 may comprise any known materials. Suitable material for the front and back belt 84, 86 can be manufactured from a wide range of materials such as plastic films; apertured plastic films; woven or nonwoven webs of natural materials (e.g., wood or cotton fibers); synthetic fibers (e.g., polyolefins, polyamides, polyester, polyethylene, or polypropylene fibers), or a combination of natural and/or synthetic fibers; or coated woven or nonwoven webs. The belt may comprise a nonwoven web of synthetic fibers. The belt may comprise a stretchable nonwoven. The belt may comprise an inner hydrophobic, non-stretchable nonwoven material and an outer hydrophobic, non-stretchable nonwoven material.
The belt 40 may comprise a first elastic section 102 (e.g., a first plurality of elastics) and a second elastic section 104 (e.g., a second plurality of elastics) located in the front belt 84. These two sections may be equally divided by longitudinal distance along the seam or equally divided from the waist end edge to the leg opening. The belt 40 may comprise a third elastic section 106 (e.g., a third plurality of elastics) and a fourth elastic section 108 (e.g., a fourth plurality of elastics) located in the back belt 86. These two sections may be equally divided by longitudinal distance along the seam or from the waist end edge to the leg opening. Fifth and sixth elastic sections 100 and 101 (having a fifth and a sixth plurality of elastics) may be disposed distal (i.e., toward the transverse axis T1) of each front and back waist regions 26 and 28. The fifth and sixth elastic sections 100 and 101 may be equally divided by longitudinal distance along the crotch region or longitudinally from the leg opening in the front to the leg opening in the back. Fifth elastic section 100 may be further equally divided by longitudinal distance to form subsections 100A and 100B. Also, sixth elastic section 101 may be further equally divided by longitudinal distance to form subsections 101A and 101B. The first elastic section 102 and the fourth elastic section 108 are adjacent to the waist opening 36. The second elastic section 104 and the third elastic section 106 are adjacent to the leg openings 34.
According to the method of defining elastic sections according to the Test Methods Section described in this application, the first elastic section 102 may comprise 20 percent to 80 percent, 25 percent, 40 percent, 50 percent, 60 percent, 70 percent of the longitudinal direction length of the front belt 84. The second elastic section 104 may comprise of 20 percent to 80 percent, 25 percent, 40 percent, 50 percent, 60 percent, 70 percent of the longitudinal direction length of the front belt 84. The third elastic section 106 may comprise 20 percent to 80 percent, 25 percent, 40 percent, 50 percent, 60 percent, 70 percent of the longitudinal direction length of the back belt 86. The fourth elastic section 108 may comprise 20 percent to 80 percent, 25 percent, 40 percent, 50 percent, 60 percent, 70 percent of the longitudinal direction length of the back belt 86.
The belt 40 may comprise a front border between the first elastic section 102 and a second elastic section 104, and the front border may be located within 5 mm, 10 mm, 20 mm, 30 mm 40 mm, 50 mm from the front edge of the absorbent core. The belt 40 may comprise a back border between the third elastic section 106 and a fourth elastic section 108, and the back border may be located within 5 mm, 10 mm, 20 mm, 30 mm 40 mm, 50 mm from the back edge of the absorbent core.
The belt 40 may comprise a first force zone 110, a second force zone 112, a third force zone 114, a fourth force zone 116, a fifth force zone 118, and a sixth force zone 120 located in the front belt 84. The first force zone 110, second force zone 112, and third force zone 114 may be located in the first elastic section 102. The fourth force zone 116, fifth force zone 118, and sixth force zone 120 may be located in the second elastic section 104.
The belt 40 may comprise a seventh force zone 122, an eight force zone 124, a ninth force zone 126, a tenth force zone 128, a eleventh force zone 130, and a twelfth force zone 132 located in the back belt 86. The seventh force zone 122, eight force zone 124, and ninth force zone 126 may be located in the third elastic section 106. The tenth force zone 128, eleventh force zone 130, and twelfth force zone 132 may be located in the fourth elastic section 108.
The thirteenth force zone 334, fourteenth force zone 336, fifteenth force zone 338, and sixteenth force zone 340 may be located in the fifth elastic section 100 in the front region of the crotch region. The seventeenth force zone 342, eighteenth force zone 344, nineteenth force zone 346, and twentieth force zone 348 may be located in the sixth elastic section 101 in the back region of the crotch region.
Force zones may be equally distanced throughout the belt along the longitudinal axis in the front and back belts 84, 86 and may each comprise a transverse force of 1 to 10 N/zone measured at a strain of 50%. Force zones may also be unequally distanced throughout the belt along the longitudinal axis in the front and back belts 84, 86. Force zones may have varying width and length. Force zones may be continuous or discontinuous, as for example, when disrupted by the main body 38 and/or absorbent core.
According to the method of defining elastic sections according to the Test Methods Section described in this application, the front belt 84 may comprise 5 to 70 or 10 to 60 elastic strands. The back belt 86 may comprise 5 to 70 or 10 to 60 elastic strands. The front crotch region may comprise 1 to 10 or 2 to 6 elastic strands. The back crotch may comprise 3 to 30 or 5 to 20 elastic strands. The elastic strands may be distributed amongst the different force zones. Elastic strands may be distributed evenly amongst the force zones. Elastic strands may also be distributed unevenly amongst the different force zones.
The elastic strands 300 may have a linear density between 200 to 2500. Linear density is the density of the elastic fibers in the elastic strand. The most commonly used unit for the linear density is the decitex, abbreviated dtex, which is the mass in grams per 10,000 meters (Dt). The linear density may be used to change the force profile. For example, one could reach a desired force profile by selecting the linear density of a single elastic strand, combining multiple elastic strands with a smaller linear density in close proximity to each other, and/or combining with other elastomeric materials.
The elastic strands may have an elastic pre-strain. The elastic pre-strain is the percent of length increase in an elastic strand or plurality of elastic strands at the point of combining the elastic(s) with the first and/or second belt layers. For example a strand with a free length of 15 centimeters (cm) may have a load applied such that the 15 cm elastic strand is now 18 cm long. This length increase of 3 cm is 20% of 15 cm (3/15), or a 20% strain. The elastic pre-strain may be used to change the force profile of a single elastic strand or a plurality of elastic strands. Force profiles may also be changed by changing the linear density in conjunction with the elastic pre-strain of one or more elastic strands.
According to the method of defining elastic sections according to the Test Methods Section described in this application, the elastic pre-strain of the first elastic section may be higher than the elastic pre-strain of the second elastic section. Similarly, the elastic pre-strain of the fourth elastic section may be higher than the elastic pre-strain of the third elastic section. This is accomplished by using higher pre-strain in elastics that are close to the first waist edge (also called the front waist edge) and the second waist edge (also called the back waist edge). This makes the circumference of the absorbent article smaller at the waist edge compared to the rest of the belt region, giving the absorbent article a more underwear like look.
According to the method of defining elastic sections according to the Test Methods Section described in this application, the elastic pre-strain of the eighth force zone 124 found in the third elastic section 106 of the back belt 86 may be greater than, equal to, or less than the elastic pre-strain of both the seventh force zone 122 and the ninth force zone 126. The elastic pre-strain of the eleventh force zone 130 found in the fourth elastic section 108 of the back belt 86 may be greater than, equal to, or less than the elastic pre-strain of both the tenth force zone 128 and the twelfth force zone 132.
According to the method of defining elastic sections according to the Test Methods Section described in this application, the linear density of the elastic in the first elastic section may be greater than the linear density in the second elastic section. Similarly, the linear density of the elastic in the fourth elastic section may be greater than the linear density in the third elastic section. This delivers a higher force at the waist edge compared to the rest of the belt, which is desired to deliver underwearlike fit. The force of the first elastic section 102 may not be equal to the second elastic section 104. The force of the third elastic section 106 may not be equal to the fourth elastic section 108. Elastics located in the fourth elastic section 108 transversely cover substantially the whole section continuously. Elastics located in the third elastic section 106 may be laterally interrupted by the main body 38 and/or absorbent core.
The number of elastic strands in each zone may be changed according to the placement of the absorbent core. Applicants have found that the use of thinner absorbent cores may lead to a need in increased elastic force to compensate for the change in article thickness. The force profile must be adjusted depending on the location and thickness of the absorbent core. This particularly affects the second, third, fifth and sixth elastic sections.
The elastic strands disposed in the belt may be aligned in a curved fashion so that a tangent of the curve of the elastic strands may form an acute angle with the centerline or may form an arcuate shape. This may allow for targeting the force profile and/or coordinating print and elastication/rugosities/elastics in the stretch sections.
The gaps between the elastic strands 300 may be 2 mm, 3 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 11 mm, 12 mm, 13 mm, 14 mm, 15 mm, 16 mm, 17 mm, 18 mm, 19 mm, 20 mm, 21 mm, or 22 mm, or 25 mm.
As shown in
The embodiment of
It should be understood that in alternative embodiments, spacers may be disposed in Section 104 in the front belt. In alternative embodiments, spacer 136c may be from 5-7 mm, spacer 136b may be from 6-8 mm, and spacer 136a may be from 7-9 mm. Further referring to
The embodiment of
As shown in
The absorbent articles of the present disclosure may be placed into packages. The packages may comprise polymeric films and/or other materials. Graphics and/or indicia relating to properties of the absorbent articles may be formed on, printed on, positioned on, and/or placed on outer portions of the packages. Each package may comprise a plurality of absorbent articles. The absorbent articles may be packed under compression so as to reduce the size of the packages, while still providing an adequate amount of absorbent articles per package. By packaging the absorbent articles under compression, caregivers can easily handle and store the packages, while also providing distribution savings to manufacturers owing to the size of the packages.
Accordingly, packages of the absorbent articles of the present disclosure may have an In-Bag Stack Height of less than about 100 mm, less than about 95 mm, less than about 90 mm, less than about 85 mm, less than about 85 mm, but greater than about 75 mm, less than about 80 mm, less than about 78 mm, less than about 76 mm, or less than about 74 mm, specifically reciting all 0.1 mm increments within the specified ranges and all ranges formed therein or thereby, according to the In-Bag Stack Height Test described herein. Alternatively, packages of the absorbent articles of the present disclosure may have an In-Bag Stack Height of from about 70 mm to about 100 mm, from about 70 mm to about 95 mm, from about 72 mm to about 85 mm, from about 72 mm to about 80 mm, or from about 74 mm to about 78 mm, specifically reciting all 0.1 mm increments within the specified ranges and all ranges formed therein or thereby, according to the In-Back Stack Height Test described herein.
Test Methods Section
These tests can be used for stretch laminates that comprise elastic strands, e.g. Spandex strands. Typically, the elastic strands are stretched and laminated between two nonwovens to make the stretch laminate. The intent of these tests is to characterize these stretch laminates in terms of i) the strand spacing, i.e. the distance from one strand to the next and ii) their dtex (or decitex). Since these tests will be done for each elastic section, it represents an average value for all the elastics in that section. These tests are suitable for pant type absorbent articles, comprising parallel strand elastics that run predominantly in the transverse direction of the product.
Sample Prep
The purpose of this step is to separate the belt 40, which comprises the elastic material 300, from the main body 38, which comprises the absorbent core 62. Place the absorbent article 20, also referred to as “product,” on the tabletop with the front side facing up. The product is laid flat on the table with the side seams intact. The product is spread out as much as possible, while still being in a relaxed state. With a marker, mark the location of the lower ends of the side seams, on the outer side of the front and the back belts; i.e. make a total of 4 marks (dots). Draw the longitudinal centerline, L1, from the first waist edge 134 (also referred to as “front waist edge”) to the second waist edge 138 (also referred to as “back waist edge”). Draw the transverse centerline, T1. Next, draw a straight line, T3, connecting the lower ends of the side seam in the front, from the left side seam to the right side seam. Turn the product over so the back side of the product is facing up. Draw a straight line, T6, connecting the lower ends of the side seam in the back, from the left side seam to the right side seam. The front waist edge, the back waist edge and lines T3, T1 and T6 divide the absorbent article in 4 parts.
Turn the product over so the front of the product is facing up. Draw line T2, parallel to line T3 and halfway between the front waist edge and T3, to form the First Elastic Section (102 in the spec) and the Second Elastic Section (104 in the spec) as shown in
Repeat these steps on the back. Draw a line T5, parallel to T1 and half way between T1 and T6, to form the Sixth Elastic Section—A (iota in the spec) and Sixth Elastic Section—B (101b in the spec) as shown in
Mark each of the eight Elastic Sections appropriately. Open up the product by cutting the sides open (at the side seams). Remove the main body from the belt. In most cases, it is a glued bond, which can be opened up using FreezeIt. Cut along the transverse lines T2, T3, T4, T1, T5, T6 and T7 to obtain the 8 Elastic Sections. If any transverse line falls exactly on an elastic, make the cut about a millimeter past that elastic, moving closer towards the transverse center line T1.
If the belt 40 has at least one nonwoven that extends the full length and width of the product, there will be all 8 Elastic Sections. If, on the other hand, the belt 40 does not have a nonwoven that extends the full length and width of the product, it is possible that there may be less than 8 Elastic Sections, depending on the width of the belt. If any of the Sections has no elastic, no measurements need to be made on it. If the belt has some curved leg elastics, do not use those elastics.
In each of the 8 Elastic Sections, measure the following. For each variable, make 5 replicate measurements (n=5).
A) Average Elastics Spacing, S
Start with the First Elastic Section. Identify the area of this Elastic Section that has elastics. If there is a gap of over 30 mm (in the longitudinal direction, parallel to L1) between adjacent elastics, then these elastics should be considered to be in two different areas within that section. If the elastic spacing is 30 mm or less, it should be counted as being in the same area. Count the number of elastics in an area. Measure the distance from the first elastic to the last elastic in an area (x1). Count the number of elastics in that area (n1). Repeat for all the areas with elastics within each Elastic Section (2, 3,). Calculate the Average Elastic Spacing for the First Elastic Section, S-first, as follows:
S-first=(x1+x2+x3+ . . . )/[(n1−1)+(n2−1)+(n3−1)+ . . . ]
where subscript 1 is for the first area, subscript 2 is for the second area, etc. within this First Elastic Section. Subscript-first is for the First Elastic Section.
Repeat this for all the 8 Elastic Sections (S-second, S-third, . . . , S-sixthB).
B) Average Elastics Dtex, Dt
The elastics may either be glued to the nonwoven or not. If the elastics are not glued to the nonwovens and are placed in the laminate as drawstring elastics, remove all the elastics from each Elastic Section of the laminate and place them separately making sure that they are labelled appropriately. No further treatment is needed on these elastics. If, on the other hand, the elastics are glued to the nonwovens, remove all the elastics by using Freezeit. Once again, ensure that the elastics from each Elastic Section are labelled appropriately and placed separately. Since these elastics have glue on them, use an appropriate solvent to dissolve the glue without affecting the elastics. For example, if the elastics are made of polyurethane (Spandex solvent may be used). Evaporate the solvent.
With the elastics removed and also freed of the glue, measure the total relaxed length of all the elastics in the First Elastic Section (L1, L2, . . . ) in mm. Next, weigh all the elastics together in the First Elastic Section (W-first) in grams.
Calculate the Average Elastics Dtex in the First Elastic Section, Dt-first, as follows:
Dt-first=(W-first)/(L1+L2+L3+ . . . )*10,000,000.
Repeat this measurement for the remaining 7 Elastic Sections (Dt-second, . . . , Dt-sixthA, Dt-sixthB).
C) Average % Pre-Strain, PS
Starting with a new product sample, i) mark the 8 Elastic Sections, ii) separate the belt 40 from the main body, and iii) cut off the 8 Elastic Sections as per the Sample Prep description in the previous test for the Average Elastics Spacing and the Average Elastics Dtex.
Take the First Elastic Section and stretch it out fully on the tabletop using masking tape to hold the sides. In this test, the stretch direction is referred to as the length direction and the direction perpendicular to the stretch direction is referred to as the width direction of the Elastic Section. It should be noted that, for this test, and also for the tensile test later on, the length direction is perpendicular to the longitudinal center line, L1, of the absorbent article, and the width direction is parallel to the longitudinal center line L1. Draw 2 vertical lines that are parallel to the longitudinal center line L1 and are at a distance of 100 mm on either side of the longitudinal center line L1. These two lines should extend the full width of the Elastic Section. This defines the fully stretched length, Lmax-first, which is 200 mm for this First Elastic Section. If the Elastic Section is not long enough to get the 200 mm long stretched sample, a shorter length may be used. This shorter length should be ˜40 mm less than the minimum length of the fully stretched Elastic Section in order to leave some room to attach the masking tape at the two sides. This shorter length is the fully stretched length, Lmax-first, for the narrower Elastic Section.
With an Exacto knife, cut off all the elastics and the nonwovens along these two lines. Keep the center portion of this Elastic section for further analysis.
Separate the elastics from the nonwovens using Freezeit. Count the number of elastics, n-first, in this First Elastic Section. If the elastics have glue on them, dissolve the glue in an appropriate solvent that does not significantly affect the elastics (e.g. Tetra hydro furan, THF, for polyurethane strands). Allow the elastics to dry out.
Measure the total relaxed length, Lr-first, of all the elastics in this First Elastic Section.
Calculate Average % pre-strain, PS-first, as follows:
PS-first=(Lmax-first n-first−Lr-first)/Lr-first*100
Repeat this measure for each of the 7 remaining Elastic Sections (PS-second, . . . , PS-sixthB).
D) Elastic Force, F
Starting with a new product sample, i) mark the 8 Elastic Sections, ii) separate the belt 40 from the main body 38, and iii) cut off the 8 Elastic Sections as per the Sample Prep description in the previous test for the Average Elastics Spacing and the Average Elastics Dtex.
Take the First Elastic Section and lay it down on the table in a relaxed state. Gently spread out the sample so it lies uniformly, while still being in a relaxed state. As in the test for measuring pre-strain, the stretch direction is referred to as the length direction and the direction perpendicular to the stretch direction is referred to the width direction for this test.
Draw 2 vertical lines that are parallel to the longitudinal center line, L1, and are at a distance of 50 mm on either side of the longitudinal center line, L1. These two lines should extend the full width of the Elastic Section. If this Elastic Section is not long enough to get this 100 mm long relaxed sample, a smaller length may be used. This smaller length should be ˜20 mm less than the minimum length of this Elastic Section.
Measure the width of this First Elastic Section, Ws-first.
Measure the tensile properties of this stretch laminate in a tensile tester as described below.
The in-bag stack height of a package of absorbent articles is determined as follows:
Equipment
A thickness tester with a flat, rigid horizontal sliding plate is used. The thickness tester is configured so that the horizontal sliding plate moves freely in a vertical direction with the horizontal sliding plate always maintained in a horizontal orientation directly above a flat, rigid horizontal base plate. The thickness tester includes a suitable device for measuring the gap between the horizontal sliding plate and the horizontal base plate to within ±0.5 mm. The horizontal sliding plate and the horizontal base plate are larger than the surface of the absorbent article package that contacts each plate, i.e. each plate extends past the contact surface of the absorbent article package in all directions. The horizontal sliding plate exerts a downward force of 850±1 gram-force (8.34 N) on the absorbent article package, which may be achieved by placing a suitable weight on the center of the non-package-contacting top surface of the horizontal sliding plate so that the total mass of the sliding plate plus added weight is 850±1 grams.
Test Procedure for In-bag Stack Height
Absorbent article packages are equilibrated at 23±2° C. and 50±5% relative humidity prior to measurement.
The horizontal sliding plate is raised and an absorbent article package is placed centrally under the horizontal sliding plate in such a way that the absorbent articles within the package are in a horizontal orientation (see
A suitable tensile tester such as an MTS Alliance with MTS Testworks version 4.0 or equivalent instrument is used. The tester is equipped with flat clamps that are capable of holding at least the entire transverse length of the side seam should be used. The instrument is calibrated according to the manufacturer's specification. Testing is performed at 23° C.±2° C. and 50%±2% relative humidity.
The side seams of the product are broken to separate the front belt from the back belt. The respective force zones (as described in the Detailed Description of the Invention) are cut away from these belts. Each separated section of the front and back belt will be referred to as a “test sample” herein. All material layers, including the chassis components, should be kept with the test sample. All cut lines are straight, parallel to the transverse direction of the absorbent article. Each test sample needs to have at least one elastomeric material. The widths (a dimension in the longitudinal direction of the absorbent article) of the respective zones are measured.
The length of the test sample is determined. The length measures in the transverse direction of the absorbent article a distance from one end to the other end of a test sample in a fully stretched condition. The fully stretched condition is the condition where the test sample is stretched by the force of 0.1 N/mm multiplied by the width of the test sample. If one or both ends of a test sample are not parallel to the longitudinal direction, the shortest length within the test sample is considered as the length of the test sample.
An adjusted test sample length is defined such that the length of a test sample minus the combined length of any material in the upper and lower clamps. Thus, if a test sample is mounted in the clamp so that 10 mm at each end is held in the clamps, then the adjusted belt length is the measured belt length minus 20 mm.
The test samples are kept unstretched at least for 10 min before the test.
For each test sample, the initial gauge length of the tensile tester is set to allow the test sample to be mounted in a relaxed state. The load cell is zeroed to offset the sample weight.
The test sample is stretched in the transverse direction of the absorbent article at a rate of 254 mm/min, and a load (N) is measured within 5 sec after the test sample reaches at 65% of the adjusted test sample length. The transverse force is calculated for each of the force zones according to an equation:
A transverse force (N/mm) of a test sample=Measured value (N)/width of the force zone (mm)
The dimensions and values disclosed herein are not to be understood as being strictly limited to the exact numeral values recited. Instead, unless otherwise specified, each such dimension is intended to mean both the recited value and a functionally equivalent range surrounding that value. For example, a dimension disclosed as “40 mm” is intended to mean “about 40 mm.”
All documents cited in the Detailed Description of the Invention are, in relevant part, incorporated herein by reference; the citation of any document is not to be construed as an admission that it is prior art with respect to the present invention. To the extent that any meaning or definition of a term in this written document conflicts with any meaning or definition of the term in a document incorporated by reference, the meaning or definition assigned to the term in this written document shall govern.
While particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of this invention.
This application claims the benefit, under 35 USC 119(e), to U.S. Provisional Patent Application No. 62/332,496 filed on May 6, 2016, which is herein incorporated by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 62332496 | May 2016 | US |
