US20040107481A1 - Process to make boxer shorts having a contracted crotch region - Google Patents

Abstract

A method of making a boxer-style pant having side seams, a contracted crotch region and hanging legs. A flat web is provided. Portions are removed from the flat web to define leg openings. The flat web is then contracted either elastically or inelastically in selected areas along the flat web between the leg openings. The flat web is cut into separate pieces, folded and side seams are formed. The pant may include an absorbent.

Description

BACKGROUND OF INVENTION
• The present invention pertains to methods of making pants having side seams and a contracted crotch region. More particularly, the present invention pertains to methods of making boxer shorts having side seams and a contracted crotch region. The boxer shorts may be absorbent or non-absorbent.[0001]
• Pant-like garments have numerous applications including disposable clothing, training pants, feminine care products, adult incontinence products, disposable swimwear, or the like. Pant-like disposable garments are typically three-dimensional products with closed sides so that the product has a unitary waist opening and two leg openings. The wearer raises and lowers the garment to apply the product. Three-dimensional, boxer shorts-like products are particularly appealing because the boxer shorts look more like conventional articles of clothes.[0002]
• Many disposable pants are formed as composite structures in which several components are combined to form a product specifically suited to its intended purpose. For example, disposable pants often include one or more absorbent materials intended to absorb various bodily exudates such as urine, menstrual fluid, and/or sweat. Such products may include a liquid permeable bodyside liner and a liquid impermeable outer cover, and can include other materials and features such as elastic materials and containment structures.[0003]
• However, many disposable pants are aesthetically unappealing. Existing disposable absorbent pants can be overly bulky and often resemble disposable baby diapers. Various attempts have been made to provide disposable pants having an improved, more clothing-like appearance. However, disposable pants, particularly disposable absorbent boxer shorts, present many manufacturing challenges. In part, this is due to the high speed that is necessary to economically produce relatively low-cost disposable absorbent products. Product design is often compromised by cost and manufacturing constraints, resulting in disposable pants that lack aesthetic appeal and product function. In addition, crotch depth is required for a good fit, but difficult to achieve in a garment like boxer-shorts with hanging legs when using conventional manufacturing processes.[0004]
• Thus, what is lacking and needed in the art are garment-like, aesthetically appealing boxer shorts, as well as methods of efficiently manufacturing such boxer shorts.[0005]
SUMMARY OF THE INVENTION
• In response to the above-referenced unfulfilled need in the art, new pants, and methods for manufacturing such pants, have been invented. The material for the garment shell of the pant is handled as a flat web throughout assembly until seaming in order to streamline the assembly. The pants can include an absorbent assembly and can be made in either the machine direction or the cross-machine direction.[0006]
• One aspect of the invention pertains to a method of making a pant having side seams and hanging legs. One embodiment of the method comprises: providing a flat web; removing at least one portion of the flat web to define at least one leg opening; contracting the flat web in selected areas, and attaching a first region and a second region together to form the side seams.[0007]
• Another aspect of the invention pertains to a method of making an absorbent pant having side seams and hanging legs. One embodiment of the method comprises: providing a flat web; removing at least one portion of the flat web to define at least one leg opening; contracting the flat web in selected areas, attaching an absorbent structure to the flat web, and attaching a first region and a second region together to form the side seams.[0008]
• Another aspect of the present invention pertains to a pant made from a single flat web. One embodiment of the pant comprises: a garment shell, the garment shell including a front region, a back region and a contracted crotch region, side seams connecting the front region to the back region, and hanging legs. The pant may also include an absorbent structure. At least a portion of each of the front region, the back region, the contracted crotch region and the hanging legs include portions of the single flat web.[0009]
• The present invention relates to a wide variety of absorbent and non-absorbent pants, including training pants, swim pants, diaper pants, incontinence garments, feminine care products, health care garments, apparel for institutional, industrial and consumer use, or other garments. Disposable absorbent pants are adapted to be worn adjacent the body of a wearer to absorb and contain various exudates discharged from the body.[0010]
BRIEF DESCRIPTION OF THE DRAWINGS
• FIG. 1 is a front view of one embodiment of a pant according to the present invention;[0011]
• FIGS. 1A and 1B illustrate dimensions described with respect to Tables 1 and 2.[0012]
• FIG. 2A is a perspective cut-away view of one embodiment of a pant according to the present invention;[0013]
• FIG. 2B is a perspective cut-away view of one embodiment of a pant according to the present invention;[0014]
• FIG. 3A is a plan view of the garment shown in FIG. 2A, showing the side facing the wearer;[0015]
• FIG. 3B is a plan view of the garment shown in FIG. 2B, showing the side facing the wearer;[0016]
• FIG. 3C is a plan view of the garment shown in FIG. 2A, showing the side facing the wearer without an absorbent structure;[0017]
• FIG. 4 is a top view of a flat web;[0018]
• FIG. 5 is a top view of the flat web of FIG. 4 including leg openings and strips applied to the flat web for assembling pants according to one embodiment of the invention in the machine direction;[0019]
• FIGS. 5A and 5B illustrate dimensions described with respect to Tables 1 and 2;[0020]
• FIG. 6 is a top view of the flat web of FIG. 5 after contraction of the flat web;[0021]
• FIG. 7 is a side view of a looper drum for applying an elastic strip to the flat web;[0022]
• FIG. 8 is a side view of a process for applying a strip to the flat web;[0023]
• FIG. 9 is a side view of a corrugating drum for corrugating the flat web of FIG. 5;[0024]
• FIG. 10 is a top view of the flat web of FIG. 4 including leg openings and strips applied to the flat web for assembling pants according to one embodiment of the invention in the cross-machine direction;[0025]
• FIG. 11 is a top view of the flat web of FIG. 10 after contraction of the flat web;[0026]
• FIG. 12 is a side view of the flat web of FIG. 10 passing through corrugating rollers for corrugating the flat web of FIG. 10.[0027]
DEFINITIONS
• Within the context of this specification, each term or phrase below will include the following meaning or meanings.[0028]
• “Attached” refers to the joining, adhering, connecting, bonding, or the like, of two elements. Two elements will be considered to be attached together when they are attached directly to one another or indirectly to one another, such as when each is directly attached to intermediate elements.[0029]
• “Bonded” refers to the joining, adhering, connecting, attaching, or the like, of two elements. Two elements will be considered to be bonded together when they are bonded directly to one another or indirectly to one another, such as when each is directly bonded to intermediate elements.[0030]
• “Boxer shorts” refers to a garment having hanging legs.[0031]
• “Comprising” is inclusive or open-ended and does not exclude additional, unrecited elements or method steps.[0032]
• “Connected” refers to the joining, adhering, bonding, attaching, or the like, of two elements. Two elements will be considered to be connected together when they are connected directly to one another or indirectly to one another, such as when each is directly connected to intermediate elements.[0033]
• “Corrugated” refers to the condition of a material which has been gathered into pleats or regular rugosites or folds, the material being shortened thereby.[0034]
• “Disposable” refers to articles which are designed to be discarded after a limited use rather than being laundered or otherwise restored for reuse.[0035]
• “Elastic,” “elasticized” and “elasticity” mean that property of a material or composite by virtue of which it tends to recover its original size and shape after removal of a force causing a deformation.[0036]
• “Elastomeric” refers to a material or composite which can be elongated by at least 25 percent of its relaxed length and which will recover, upon release of the applied force, at least 10 percent of its elongation. It is generally preferred that the elastomeric material or composite be capable of being elongated by at least 100 percent, more preferably by at least 300 percent, of its relaxed length and recover, upon release of an applied force, at least 50 percent of its elongation.[0037]
• “Fabrics” is used to refer to all woven, knitted and nonwoven fibrous webs.[0038]
• “Flat web” comprises any material used for making garments that can be provided and processed in a substantially open, unfolded state; while the web can possess ripples or areas that do not lie exactly within an overall plane of the web, all points of the web should be reasonably identifiable as constituents in either an upper or a lower surface of the web. No portions of a flat web are enclosed or fixed into a loop or tunnel-like, or three-dimensional configuration.[0039]
• “Garment shell” refers to an outer cover or outer layer of a garment. In a single-ply garment, the single layer of the garment is the garment shell.[0040]
• “Garment insert” refers to an inner layer of a garment. The garment insert provides a close-to-the-body fit about a wearer's lower torso, thereby serving as a form of built-in underwear within the garment.[0041]
• “Hanging legs” refers to the portions of a garment which extend from the crotch region downward to the leg openings. “Downward” refers to a direction toward the ground when the garment is positioned on a standing wearer.[0042]
• “Hydrophilic” describes fibers or the surfaces of fibers which are wetted by the aqueous liquids in contact with the fibers. The degree of wetting of the materials can, in turn, be described in terms of the contact angles and the surface tensions of the liquids and materials involved. Equipment and techniques suitable for measuring the wettability of particular fiber materials or blends of fiber materials can be provided by a Cahn SFA-222 Surface Force Analyzer System, or a substantially equivalent system. When measured with this system, fibers having contact angles less than 90 are designated “wettable” or hydrophilic, while fibers having contact angles greater than 90 are designated “nonwettable” or hydrophobic.[0043]
• “Integral” is used to refer to various portions of a single unitary element rather than separate structures bonded to or placed with or placed near one another.[0044]
• “Layer” when used in the singular can have the dual meaning of a single element or a plurality of elements.[0045]
• “Liquid impermeable”, when used in describing a layer or multi-layer laminate, means that a liquid, such as urine, will not pass through the layer or laminate, under ordinary use conditions, in a direction generally perpendicular to the plane of the layer or laminate at the point of liquid contact. Liquid, or urine, may spread or be transported parallel to the plane of the liquid impermeable layer or laminate, but this is not considered to be within the meaning of “liquid impermeable” when used herein.[0046]
• “Machine direction” refers to the length of a fabric in the direction in which it is produced, as opposed to “cross-machine direction” which refers to the width of a fabric in a direction generally perpendicular to the machine direction.[0047]
• The term “machine direction assembly” refers to a manufacturing process in which disposable products travel in an end-to-end or waist-to-waist orientation, in the longitudinal direction shown by[0048]arrow48 in FIG. 5. A process utilizing a machine direction assembly entails products traveling through a converting machine parallel to the direction ofarrow102, as opposed to “cross-machine direction assembly” in which the products travel in a side-by-side orientation such as that shown byarrow49 in FIG. 10.
• “Member” when used in the singular can have the dual meaning of a single element or a plurality of elements.[0049]
• “Nonwoven” and “nonwoven web” and “web” refer to materials and webs of material which are formed without the aid of a textile weaving or knitting process.[0050]
• “Operatively joined,” with reference to the attachment of an elastic member to another element, means that the elastic member when attached to or connected to the element, or treated with heat or chemicals, by stretching, or the like, gives the element elastic properties; and with reference to the attachment of a non-elastic member to another element, means that the member and element can be attached in any suitable manner that permits or allows them to perform the intended or described function of the joinder. The joining, attaching, connecting or the like can be either directly, such as joining either member directly to an element, or can be indirectly by means of another member disposed between the first member and the first element.[0051]
• The term “spunbonded fibers” refers to small diameter fibers which are formed by extruding molten thermoplastic material as filaments from a plurality of fine capillaries of a spinnerette having a circular or other configuration, with the diameter of the extruded filaments then being rapidly reduced as by, for example, in U.S. Pat. No. 4,340,563 to Appel et al., U.S. Pat. No. 3,692,618 to Dorschner et al., U.S. Pat. No. 3,802,817 to Matsuki et al., U.S. Pat. Nos. 3,338,992 and 3,341,394 to Kinney, U.S. Pat. No. 3,502,763 to Hartman, U.S. Pat. No. 3,502,538 to Petersen, and U.S. Pat. No. 3,542,615 to Dobo et al. Spunbond fibers are quenched and generally not tacky on the surface when they enter the draw unit, or when they are deposited onto a collecting surface. Spunbond fibers are generally continuous and may have average diameters larger than 7 microns, often between about 10 and 30 microns.[0052]
• “Stretchable” means that a material can be stretched, without breaking, by at least 50% (to 150% of its initial (unstretched) length) in at least one direction, suitably by at least 100% (to 200% of its initial length), desirably by at least 150% (to at least 250% of its initial length).[0053]
• “Surface” includes any layer, film, woven, nonwoven, laminate, composite, or the like, whether pervious or impervious to air, gas, and/or liquids.[0054]
• “Three-dimensional garment” refers to a garment that cannot be laid flat with all of its seams in one plane.[0055]
• These terms may be defined with additional language in the remaining portions of the specification.[0056]
DESCRIPTION OF PREFERRED EMBODIMENTS
• As representatively illustrated in FIGS. 1, 2A and[0057]2B, an embodiment of apant10 of the present invention includes agarment shell64. Thegarment shell64 can include afront region22, aback region24, a contractedcrotch region26, aninner surface28 which is configured to contact the wearer, and anouter surface30 opposite theinner surface28 which is configured to contact the wearer's clothing. Thepant10 also defines a pair of longitudinally opposed waist edges, which are designatedfront waist edge38 and backwaist edge39. Thefront region22 is contiguous with thefront waist edge38, and theback region24 is contiguous with theback waist edge39. Thefront region22 includes the portion of thepant10 which, when worn, is positioned on the front of the wearer while theback region24 includes the portion of thepant10 which, when worn, is positioned on the back of the wearer. The contractedcrotch region26 of thepant10 includes the portion of the pant which, when worn, is positioned between the legs of the wearer and covers the lower torso of the wearer. As illustrated in FIGS. 1, 2A and2B the front andback regions22 and24 are joined together at side seams54 to define a three-dimensional pant configuration having awaist opening50 and a pair ofleg openings52. In particular embodiments, thepant10 can include anabsorbent structure60. Various embodiments of these and other features will now be described.
• The[0058]garment shell64 includes a contractedcrotch region26. As described more fully below, the contraction of the contractedcrotch region26 can be accomplished either elastically or inelastically. The contractedcrotch region26 provides crotch depth that provides a good fit through the contractedcrotch region26. Thegarment shell64 can also include hanginglegs23 which extend from the contractedcrotch region26 downward to the leg openings52 (FIGS. 1, 2A and2B).
• The[0059]pant10 also includes side seams54 which connect thefront region22 to theback region24 to create thepant10. The side seams54 can take any number of forms, including both refastenable and non-refastenable seams as is known in the art. The provision of the side seams54 can be accomplished in the manner described in U.S. Pat. No. 5,046,272, issued Sep. 10, 1991 to Vogt et al., which is incorporated herein by reference, or in the manner described in PCT Publications WO 01/87562 by Tomsovic, et al., WO 01/87217 by Durrance, et al., WO 01/87753 by Hietpas, and or WO 01/87218 by Vogt, et al., all of which which are incorporated herein by reference. As is known in the art, the side seams54 can be inward or outward fin seams or lap seams (not shown).
• The[0060]pant10 can also have a waistelastic member58 extending along at least a portion of thefront waist edge38 and/or theback waist edge39. The waistelastic member58 can be formed of any suitable elastic material. As is well known to those skilled in the art, suitable elastic materials include sheets, strands or ribbons of natural rubber, synthetic rubber, or thermoplastic elastomeric polymers. The elastic materials can be stretched and adhered to a substrate, adhered to a gathered substrate, or adhered to a substrate and then elasticized or shrunk, for example with the application of heat, such that elastic constrictive forces are imparted to the substrate. In one particular embodiment, for example, the waistelastic member58 includes a plurality of dry-spun coalesced multifilament spandex elastomeric threads sold under the trade name LYCRA® and available from E.I. du Pont de Nemours and Company, Wilmington, Del., U.S.A. Alternatively, multiple strands of 310 decitex LYCRA® (may be also laminated at 250% elongation between spunbond facings in addition to an adhesive.
• As another alternative, the waist[0061]elastic member58 can be a material exhibiting delayed retraction, or can in fact be non-elastic. Delayed retraction materials may include those designed to retract relatively slowly following compression, such as “temporarily inhibited” elastic materials. “Temporarily inhibited” materials are described, for example, in U.S. Pat. No. 5,545,158 issued Aug. 13, 1996, to Jessup, U.S. Pat. No. 5,669,996 issued Sep. 23, 1997, to Jessup, and U.S. Pat. No. 5,500,063 issued Mar. 19, 1996, to Jessup, all of which are herein incorporated by reference, and references cited therein. Alternatively, a delayed retraction material may be designed to resist retraction until an activation process occurs, such as so-called “latent elastic” materials. Suitable retractive materials for use as a delayed retraction material can alternatively comprise any material adapted to retract upon activation, whether immediately upon activation or subsequently thereto. The retractive material can comprise elastomeric or nonelastomeric materials. Suitable nonelastomeric retractive materials can comprise without limitation polyether block amides (PEBAX®) or the like, and laminates thereof. Suitable elastromeric retractive materials can comprise without limitation LYCRA® materials, elastomeric materials including latex or rubber or synthetic urethanes, or the like, and laminates thereof. In particular embodiments, the retractive material can comprise an elastomeric material having an unstable state relative to some other stable and elastic state. In such embodiments, the retractive material can, but need not, have elastomeric properties in the unstable state. Other examples include heat-shrinkable elastic materials such as described in U.S. Pat. No. 4,816,094 issued Mar. 28, 1989 to Pomplun et al., U.S. Pat. No. 4,665,306 issued May 12, 1987 to Roland et al., and U.S. Pat. No. 4,663,106 issued May 5, 1987 to Pomplun et al., all of which are herein incorporated by reference.
• A pant of this type can be designed to fit wearers in a wide range of sizes, by adjusting the pant dimensions based on the anthropometric features of an intended wearer. Ratios of wearer dimensions to pant dimensions for a suitable boxer-style pant have been determined and are shown in Table 1. In addition, stylistic variations such as hip-hugging (low rise), relatively more closely or loosely fitted shorts, and other styles, may be provided by varying the ratios listed in Table 1 within (or even beyond) the ranges shown. Moreover, the use of elastomeric or extensible material to form the garment shell may provide additional adaptability to fit a wider range of wearer sizes.[0062]
• Since the pant dimensions are determined by the dimensions of the intended wearer, the ratios shown are based upon five measurements of an intended wearer, abbreviated as follows:[0063]
• A: waist circumference (FIG. 1A)[0064]
• B: hip circumference (FIG. 1A)[0065]
• C: thigh circumference (measured in crotch region, horizontally; see FIG. 1A)[0066]
• D: crotch depth (measured in crotch region, viewed 18 inches from the wearer's side; see FIG. 1B)[0067]
• E: center front waist to center back waist through crotch; see FIG. 1B[0068]
• Table 2 shows how garment shell dimensions shown in FIGS. 5A and 5B are determined using body measurements A-E and ratios in Table 1. Table 2 also shows how the ratios in Table 1 have been applied to create shorts for two different size wearers, one a mannequin of a child (Wearer #1) weighing approximately 32 to 40 pounds (15-18 Kg), the other an adult female (Wearer #2) weighing approximately 125 pounds (57 Kg).[0069]

  TABLE 1
  PANT DIMENSIONS	DETAILS and RATIOS	EXEMPLARY RANGES
  Garment inseam I	Selected based on garment	1-5 inches, or more
  (FIG. 5A, dimension “I”)	style. There is not a seam at
  	this location; this is simply
  	the location where an
  	“inseam” measurement is
  	generally taken. After
  	contraction, this dimension
  	“I” provides the “hanging
  	legs” feature of the pant.
  Width of garment shell	Ratio of 2x Width (i.e.,	From about 1.2:1 to about
  (FIG. 5A, dimension “w”)	garment circumference) to	2:1, such as about 1.7, e.g.
  	the larger of wearer's Hip or	2w = 1.2A or 1.2B
  	Waist circumference
  	2w:[B or A]
  Length of base of arc (FIG.	Ratio of Arc base length to	From about 1:1 to about
  5A, dimension “b”)	Wearer crotch depth	1.5:1, such as about 1.25:1
  	b:D
  Circumference of leg	Ratio of Leg opening to	From about 1.1:1 to about
  opening (FIG. 5A,	Wearer thigh circumference	1.5:1, such as about 1.25:1
  dimension “c”)	c:C
  Takeup (shortening) of	Ratio of Takeup to 2x	From about 1:1 to about
  garment shell on gathering	Garment inseam length I	1.6:1, such as about 1.3:1
  of crotch (FIG. 5B,	s:2I
  dimension “s”)
  Length of garment shell	Ratio of Length after	This can vary widely
  after gathering (FIG. 5B,	gathering to Wearer F to B	depending on the desired
  dimension “l”)	waist thru crotch	short style, but for a
  	1:E	standard fit, from about 1.1:1
  		to about 1.4:1, such as
  		about 1.25:1, e.g. 1 = 1.4E
  Length of garment shell	Sum of Takeup and Length
  before gathering (FIG. 5A,	of shell after gathering
  dimension “L”)	s + 1
  Arc height (FIG. 5A,	(Width of garment shell − 2x
  dimension“a”)	Garment inseam I)/2
  	(w − 2I)/2

• [0070]

  	TABLE 2
  		Wearer #1	Short #1	Wearer #2	Short #2
  	A	50 cm		78cm
  	B
  	54 cm		96 cm
  	C	29 cm		55cm
  	D
  	10 cm		16.5 cm
  	E	41 cm		61 cm
  	I		6 cm		8 cm
  	w		45 cm		67 cm
  	b		12.5 cm		20.5 cm
  	c		36 cm		68 cm
  	s		15.5 cm		21 cm
  	l		50.5 cm		75 cm
  	L		66 cm		96 cm
  	a		15 cm		25 cm

• The[0071]pant10 can also include anabsorbent structure60. Theabsorbent structure60 can be attached to thegarment shell64 at thefront waist edge38 and backwaist edge39, or at some point below thefront waist edge38 and backwaist edge39 on thefront region22 and backregion24. (FIGS. 2A and 2B). Alternatively, theabsorbent structure60 can be attached to thegarment shell64 in the contractedcrotch region26.
• The[0072]absorbent structure60 can be any structure which is generally compressible, conformable, non-irritating to the skin, and capable of absorbing and retaining liquids and certain body wastes. Theabsorbent structure60 can be manufactured in a wide variety of sizes and shapes, from a wide variety of liquid absorbent materials commonly used in the art, and may be stretchable, non-stretchable, or elastic. For example, theabsorbent structure60 can suitably include a matrix of hydrophilic fibers, such as a web of cellulosic fluff, mixed with particles of a high-absorbency material commonly known as superabsorbent material. In a particular embodiment, theabsorbent structure60 includes a matrix of cellulosic fluff, such as wood pulp fluff, and superabsorbent hydrogel-forming particles. The wood pulp fluff can be exchanged with synthetic, polymeric, meltblown fibers or short cut homofil bicomponent synthetic fibers and natural fibers. The superabsorbent particles can be substantially homogeneously mixed with the hydrophilic fibers or can be nonuniformly mixed. The fluff and superabsorbent particles can also be selectively placed into desired zones of theabsorbent structure60 to better contain and absorb body exudates. The concentration of the superabsorbent particles can also vary through the thickness of theabsorbent structure60. Alternatively, theabsorbent structure60 can include a laminate of fibrous webs and superabsorbent material or other suitable means of maintaining a superabsorbent material in a localized area.
• Suitable superabsorbent materials can be selected from natural, synthetic, and modified natural polymers and materials. The superabsorbent materials can be inorganic materials, such as silica gels, or organic compounds, such as crosslinked polymers, for example, sodium neutralized polyacrylic acid. Suitable superabsorbent materials are available from various commercial vendors, such as Dow Chemical Company located in Midland, Mich. U.S.A., and Stockhausen GmbH & Co. KG, D-47805 Krefeld, Federal Republic of Germany. Typically, a superabsorbent material is capable of absorbing at least about 15 times its weight in water, and desirably is capable of absorbing more than about 25 times its weight in water.[0073]
• In one embodiment, the[0074]absorbent structure60 includes a blend of wood pulp fluff and superabsorbent material. One preferred type of pulp is identified with the trade designation CR1654, available from U.S. Alliance, Childersburg, Ala. U.S.A., and is a bleached, highly absorbent sulfate wood pulp containing primarily soft wood fibers and about 16 percent hardwood fibers. As a general rule, the superabsorbent material is present in theabsorbent structure60 in an amount of from 0 to about 90 weight percent based on total weight of the absorbent assembly. Theabsorbent structure60 suitably has a density within the range of about 0.10 to about 0.35 grams per cubic centimeter. Theabsorbent structure60 may or may not be wrapped or encompassed by a suitable tissue wrap that may help maintain the integrity and/or shape of the absorbent assembly.
• The[0075]absorbent structure60 can also incorporate other materials that are designed primarily to receive, temporarily store, and/or transport liquid along the mutually facing surface withabsorbent structure60, thereby maximizing the absorbent capacity of the absorbent assembly. One suitable material is referred to as a surge layer (not shown) and includes a material having a basis weight of about 50 to about 120 grams per square meter, and including a through-air-bonded-carded web of a homogenous blend of 60 percent 3 denier type T-256 bicomponent fiber including a polyester core/polyethylene sheath and 40 percent 6 denier type T-295 polyester fiber, both commercially available from Kosa Corporation of Salisbury, N.C. U.S.A.
• In particular embodiments, the[0076]absorbent structure60 is thin to provide a slim, comfortable,non-bulky pant10. Any suitable thin absorbent structure may be used, such as for example, the thin absorbent described in WO 02/49565, published Jun. 27, 2002, by Sawyer et al., which is incorporated herein by reference.
• The[0077]absorbent structure60 can include a pair of containment flaps62 (FIG. 3A) which are configured to provide a barrier to the transverse flow of body exudates. A flap elastic member (not shown) can be operatively joined with eachcontainment flap62 in any suitable manner as is well known in the art. The elasticized containment flaps62 define an unattached edge which assumes an upright, generally perpendicular configuration to form a seal against the wearer's body. Suitable constructions and arrangements for the containment flaps62 are generally well known to those skilled in the art and are described in U.S. Pat. No. 4,704,116 issued Nov. 3, 1987 to Enloe, which is incorporated herein by reference.
• In the alternative, a pant-like garment insert could be used for the[0078]absorbent structure60. For example, the pant-like garment insert suitably includes a body side liner, an outer cover, and an absorbent assembly between the body side liner and the outer cover, and side panels. Examples of suitable pant-like garment inserts include a training pant, such as HUGGIES® PULL-UPS® Disposable Training Pants, or a disposable underpant, such as GOODNIGHTS® Disposable Underpants, both manufactured by Kimberly-Clark Corporation, Neenah, Wis., U.S.A. A training pant as the pant-like garment insert for theabsorbent structure60 can includefront side panels34 and back side panels134 (FIGS. 2B and 3B). The manufacture of training pants having side panels can be accomplished in the manner described in U.S. patent application Ser. No. 09/855,484, filed 15 May 2001 (U.S. Publication US 2002/0000291, Jan. 3, 2002) by Joseph D. Coenen et al., which is incorporated herein by reference.
• As another alternative, a pad-type absorbent could be used for the absorbent structure. The pad-type absorbent can be attached in the crotch-[0079]region26 of thepant10. An example of a suitable pad-type absorbent is a feminine care pad such as KOTEX® Feminine Napkins, KOTEX® LIGHTDAYS® disposable panty liners, or an incontinence absorbent pad such as POISE® Feminine Guards and Pads or DEPEND® Guards for MEN, all manufactured by Kimberly-Clark Corporation, Neenah, Wis., U.S.A.
• For reference,[0080]arrows48 and49 depicting the orientation of the longitudinal axis and the transverse axis, respectively, of thegarment shell64 are illustrated in FIGS. 3A and 3C.
• The[0081]garment shell64 is desirably constructed of materials which are comfortable against the skin and non-irritating. It is contemplated that thegarment shell64 can be either disposable or durable, in the embodiments without an absorbent structure, and disposable in the embodiments with an absorbent structure. Both nonwoven and woven materials are contemplated for thegarment shell64. For example, thegarment shell64 forpant10 can be selected from a wide variety of materials, including elastic, stretchable, or nonstretchable materials. Thegarment shell64 can be a single layer of material or a multi-layered laminate structure. One example of a suitable material is a spunbond polypropylene nonwoven web. Thegarment shell64 may also be made of those materials of which theabsorbent structure60 is made. It is desired that thegarment shell64 provides a relatively cloth-like texture to the wearer.
• The present invention also includes various methods for making pants having side seams from a flat web, as shall now be explained and illustrated. Referring to FIG. 4, a single[0082]flat web100 is provided moving in the direction represented byarrow102. In the alternative, two webs that are joined at their edges to form a double-width piece (not shown) can be used for theflat web100. Theflat web100 can be composed of any material previously described for thegarment shell64.
• The method of the present invention can be carried out using machine direction assembly so that[0083]arrow102 can correspond to the longitudinal direction as shown by arrow48 (FIG. 5) with the products connected end to end or waist to waist, or the method of the present invention can be carried out using cross-machine direction assembly so thatarrow102 can correspond to the transverse direction as shown by arrow49 (FIG. 10) with the products connected side-to-side.
• In the machine direction process (FIGS.[0084]5-9), portions of theflat web100 are removed to define leg openings104 (FIG. 5) by die cutting, or by any other suitable method known in the art. Theleg openings104, as more fully described below, become theleg openings52 of thepant10.
• Strips[0085]106 are applied to the selected areas located between theleg openings104.Strips106 can include elastic or non-elastic material. Examples of suitable non-elastic material include heat contractible materials, such as heat shrinkable films, for example, films formed of polyether block amides (PEBAX®, available from the Atofina Company of France) or the like. If thestrips106 are elastic, the elastic can be formed of any suitable material previously described for the waistelastic member58. As an alternative, strips106 can include any of the previously described delayed retraction materials.
• Referring to FIG. 7, if the[0086]strips106 are elastic, thestrips106 can be applied to theflat web100 using alooper drum108. Looper drums likelooper drum108 are known and are described, for example, in U.S. Pat. No. 5,171,388 issued Dec. 15, 1992 to Hoffman et al., herein incorporated by reference.Drum108 includessurface grooves110.Drum108, as illustrated in FIG. 7, includes foursurface grooves110, but any number ofsurface grooves110 may be included. Thesurface grooves110 are spaced around thedrum108 So that eachgarment shell64 eventually includes onestrip106. Theflat web100 travels around thedrum108 in the direction ofarrow102. Theflat web100 runs down into thesurface grooves110 by virtue of the fact that thedrum108 includes apertures across its surface and is under vacuum. Adhesive (shown for purposes of illustration as dots betweenstrip106 and theflat web100 over the surface groove110) is applied to thestrip106. In the alternative, the adhesive can be applied to theflat web100 in the selected areas betweenleg openings104. Suitable adhesives, which can be applied continuously or intermittently as beads, a spray, parallel swirls, or the like, can be obtained from Findley Adhesives, Inc., of Wauwatosa, Wis. U.S.A., or from National Starch and Chemical Company, Bridgewater, N.J. U.S.A
• The[0087]flat web100 passes by theelastic application module112 and thestrip106 of elastic is applied in a substantially unstretched condition to theflat web100 over thesurface groove110. Theflat web100 with thestrip106 of elastic continues moving in the direction ofarrow102 out ofsurface groove110 and off thedrum108. Theflat web100 withstrip106 of elastic passes through nip114 to press and secure thestrip106 of elastic to theflat web100. Thenip114 is defined byrolls116 turning in the direction ofarrows118. In the alternative, any other suitable method for pressing and securing thestrip106 of elastic to theflat web100 can be used. As theflat web100 exits thenip114, theflat web100 can be drawn at a slower rate by the downstream process than the surface speed ofrolls116, allowing thestrip106 of elastic to contract and reduce the length ofweb100.
• FIG. 6 shows the[0088]flat web100 after the contraction of thestrips106. The contraction of theflat web100 defines contractedareas120 in the selected areas betweenleg openings104. The contractedarea120, as described more fully below, becomes the contractedcrotch region26 of thepant10.
• In the alternative, the[0089]strip106 can be applied to theflat web100 by any other method known in the art such as, for example, a corrugating drum such as that described in U.S. Pat. No. 4,397,704 issued Aug. 9, 1983 to Frick, an elastic application system in which the material is gathered into folds running in the cross-machine direction and a continuous elastic is applied in the machine direction and severed at the location of the folds in the base material such as described in U.S. Pat. No. 4,417,938 issued Nov. 29, 1983 to Sigl, an intermittent adhesive application that allows the elastic to snap back from non-adhesive zones, a high efficiency interface roll such as that described in U.S. Pat. No. 6,022,443 issued Feb. 8, 2000 to Rajala et al., U.S. Pat. No. 5,556,504 issued Sep. 17, 1996 to Rajala et al., and U.S. Pat. No. 6,319,347 issued Nov. 20, 2001 to Rajala et al., all of which are here incorporated by reference, or by any other any means known in the art.
• FIGS. 6 and 11 also show waist elastics[0090]58 applied to theflat web100. The waist elastics58 can be applied by any method known in the art at any stage in the manufacturing of thepant10.
• In the alternative, the tension on the[0091]flat web100 can be reduced by cutting theflat web100 into separate pieces approximately midway betweensuccessive strips106 to define a garment shell64 (FIG. 3C). It is also contemplated, however, that the step of cutting theflat web100 can be carried out after contraction of theflat web100.
• Referring to FIG. 8, in the alternative, the[0092]strips106, whether elastic or nonelastic, can be applied to the selected areas of theflat web100 between theleg openings104 by a cut and place module as is commonly known in the art.
• Next, the[0093]flat web100 can be contracted elastically or inelastically by any suitable means. For example, if thestrip106 is an elastic capable of delayed retraction, theflat web100 can be contracted by activating thestrip106 to restore the elasticity by time, temperature, radiation or other appropriate energy. In the alternative, if thestrip106 is a heat shrinkable material, theflat web100 can be contracted inelastically by activating the heat shrinkable material by applying heat or other appropriate energy.
• In particular embodiments, the[0094]strips106 are applied to theflat web100 after contraction or pregathering of theflat web100. In the machine direction, theflat web100 can be pregathered by corrugating in the selected areas between theleg openings104 by using a corrugating drum150 (FIG. 9) in preparation for attachment ofstrip106. Corrugating drums like corrugatingdrum150 are known and are described, for example, in previously mentioned U.S. Pat. No. 4,397,704 issued Aug. 9, 1983 to Frick. Alternatively, a drum with discontinuous grooves that correlate with the location ofstrips106 can be used. Theflat web100 travels around thedrum150 in the direction ofarrow158. Pressingroll154 hasteeth156. Theflat web100 is pushed down into thegrooves152 by theteeth156, thereby corrugating theflat web100.Drum150 andpressing roller154 move in the direction ofarrows158 and160, respectively.
• Next, the[0095]strips106 can be applied to the corrugatedflat web100 by a conventional cut and place applicator.Strips106 can be attached to theweb100 using adhesive, thermal or ultrasonic bonding, or other means known in the art. Use of a corrugating drum or other device to pregather theflat web100 permits the use of an unstretched elastic or of a non-elastic, non-retractive material such as a film or nonwoven material with properties similar toflat web100. Alternatively, thestrip106 may include any of the previously described materials. Thestrips106 maintain the corrugation in the contracted area120 (FIG. 6).
• In the cross-machine direction process (FIGS.[0096]10-12), portions of theflat web100 are removed to defineleg openings104 by die cutting, or by any other suitable method known in the art. Theleg openings104, as more fully described below, become theleg openings52 of thepant10.
• As with the machine direction assembly process, strips[0097]106 are applied to the selected areas located between theleg openings104. In the cross-machine direction assembly process, strips are applied on theflat web100 in an orientation perpendicular toarrow102, as shown in FIG. 10.
• The application of[0098]strip106 of elastic material can be accomplished by a variety of methods, such as by moving the distal edges of theflat web100 closer together and allowing the center portion of the web to become looped using the same principles of the previously described looper drum, but with thestrip106 being applied in an orientation perpendicular toarrow102, or by other methods as are known in the art. As with the previously described looper drum, theflat web100 can be fully extended again after application of thestrip106 in order to fully adhere thestrip106 to theweb100. In alternative embodiments, thestrips106 can be applied to theflat web100 by a process in which an elastic or inelastic piece of material is cut, rotated and placed onto theflat web100, for example, as described in U.S. Pat. No. 5,716,478 issued Feb. 10, 1998 to Boothe et al., U.S. Pat. No. 5,759,340 issued Jun. 2, 1998 to Boothe et al. and U.S. Pat. No. 4,608,115 issued Aug. 26, 1986 to Schroth et al., all of which are herein incorporated by reference, or by any other means known in the art. Where thestrip106 is a heat contractible material or a material capable of delayed retraction, the strip can be applied toweb100 as the web travels in the direction of arrow102 (FIG. 10) in a flat and unlooped state.
• Next the[0099]flat web100 can be contracted elastically or inelastically by any of the previously described methods. FIG. 11 shows theflat web100 after the contraction of thestrips100. The contraction of theflat web100 defines contractedarea120 in the selected areas between theleg openings104. The contractedarea120, as described more fully below, becomes the contractedcrotch region26 of thepant10.
• In particular embodiments, the[0100]strips106 are applied to theflat web100 after contraction or pregathering of theflat web100. In the cross-machine direction, theflat web100 can be pregathered by corrugating in the selected areas between theleg openings104 by using intermeshinggrooved rollers170 and172 (FIG. 12) in preparation for attachment ofstrip106. Intermeshing grooved rollers like170 and172 are known in the art and are described, for example, in U.S. Pat. No. 5,755,902 issued May 26, 1998 to Reynolds, herein incorporated by reference.Roller170 includesgrooves174 only in the middle portion of the roll to correspond to the desired location of the contractedarea120 on the flat web. Theflat web100 travels through nip176 formed byrolls170 and172 in the direction ofarrow102.Roller172 has complementary grooves (not shown) designed to intermesh withgrooves174 ofroller170. Theflat web100 is pushed into thegrooves174 by the complementary grooves onroll172 to provide the corrugation in the contractedarea120.Rolls170 and172 move in the direction ofarrows178 and180, respectively. The corrugations are held in place by attachingstrips106 on top of the corrugations.
• The[0101]strip106 can be applied to the corrugatedflat web100 by a cut and place module as is commonly known in the art and can be attached to the web using thermal, ultrasonic or adhesive bonding, or any other means known in the art. Thestrip106 may include an inextensible material such as a film or nonwoven material with properties similar toweb100, or may include any of the previously described materials.
• In either the machine direction process or the cross-machine direction process, the[0102]flat web100 can now be cut into individual pieces, each of which will form agarment shell64. The cutting can be accomplished by, for example, pinch cutting, shear cutting or any other means known in the art. As another alternative, theflat web100 can be provided as separate pre-cut pieces each of which pre-cut separate pieces will eventually become asingle garment shell64, so that this cutting step could be skipped and the process could start with a pre-cut piece as theflat web100. FIG. 3C shows thegarment shell64 prior to folding and formation of the side seams54. As shown and as previously mentioned with respect to FIGS. 1, 2A, and2B thegarment shell64 can include afront region22, aback region24, a contractedcrotch region26, aninner surface28, and an outer surface30 (not shown),front waist edge38, backwaist edge39, and waistelastic member58. Thegarment shell64 can also includestrip106. It is also contemplated that thegarment shell64 can be made upside-down, i.e., with theinner surface28 facing downwardly (not shown). Thegarment shell64 can then be folded and the side seams54 formed by any conventional method known in the art to form the pant10 (without an absorbent structure). It is contemplated that the step of contracting theflat web100 can occur either before or after the step of cutting intoindividual garment shells64, and also before or after the formation of the side seams54.
• In either the machine direction process or the cross-machine direction process, in alternative embodiments, the[0103]strip106 need not be a single strip of material. In particular embodiments, elastic strands or ribbons as are known in the art can be used instead of a single strip of material forstrip106. The elastic strands or ribbons can be straight or curved. In addition, in the embodiments in which the flat web is corrugated, it is contemplated that instead of attaching astrip106, the corrugation in the contractedarea120 can be maintained by fusing or bonding the corrugations together in the selected areas between theleg openings104. The corrugations can be bonded to themselves to hold them in place by adhesive, thermal or pressure bonding, or by any other means known in the art.
• In the machine direction process, the[0104]strip106 need not be a separate piece of material applied to theflat web100. Instead, theflat web100 may include an integral elastic zone aligned along the machine direction center line, instead ofstrip106, with the elastic zone active in only the crotch region. Elastization of only the crotch region of the pant may be achieved by, for example, an elastic laminate structure in which the elastic is attached to the laminate using an intermittent adhesive. Intermittent adhesive application would allow the elastic to snap back from non-adhesive zones, which would be uncontracted as a result; contracted, adhesive-bearing zones can be located only in the crotch region of the garment. As an alternative, the elastic nature of certain regions may be inactivated by chopping or overbonding the elastic or other methods known in the art, for example, as described in U.S. Pat. No. 6,248,097 issued Jun. 19, 2001 to Beitz, herein incorporated by reference.
• Referring to FIGS. 2A, 2B,[0105]3A and3B in particular embodiments, anabsorbent structure60 is included in thepant10. Theabsorbent structure60 can be introduced into thepant10 in any suitable manner known in the art. In particular embodiments, theabsorbent structure60 can be placed on top of the contractedcrotch region26 on theinner surface28 of thegarment shell64, either prior to formation of side seams54 or after side seams54 are made. It is also contemplated, however, that theabsorbent structure60 can be attached prior to contracting and/or cutting theflat web100. Where theabsorbent structure60 is added to thepant10 prior to formation of side seams54, cut and place methods such as are known in the art may be used. Alternatively, for a closed pant (i.e., side seams already formed), theabsorbent structure60 may be inserted into the pant such as by the method described in the PCT Publication WO 02/52967 by Rabe, et al., or by other means as may be known in the art. Theabsorbent structure60 can be attached to thegarment shell64 at thefront waist edge38 and backwaist edge39, or at some point below thefront waist edge38 and backwaist edge39 on thefront region22 and backregion24. Additionally or alternatively, theabsorbent structure60 can be attached in the contractedcrotch region26. The attachment can be accomplished by ultrasonic or adhesive bonding, or any other suitable method known in the art. As shown in FIGS. 2A and 2B, attachment to the front andback regions22 and24 provides for a loose fit in the contractedcrotch region26.
• In particular embodiments, the[0106]absorbent structure60 is stretchable or elasticizable in order to provide the desired close to the body fit for theabsorbent structure60 while thegarment shell64 hangs loosely. Alternatively, a suspension system for the absorbent structure may be required to provide a loose fit for thegarment shell64, such as described in U.S. Pat. No. 6,168,585 issued Jan. 2, 2001 to Cesco-Cancian, herein incorporated by reference.
• The[0107]garment shell64 with theabsorbent structure60 can then be folded and the side seams54 formed by any conventional method known in the art to form thepant10, as shown in FIGS. 2A and 2B. After folding thegarment shell64 and forming the side seams54 (with or without an absorbent structure60), if a temporarily inhibited elastic or latent elastic is used as the waist elastic58, it may need to be activated to restore the elasticity.
• The various components of the pant can be connected together by any means known to those skilled in the art such as, for example, adhesive, thermal and/or ultrasonic bonds, pressure bonds and also sewing and other methods used in durable garment manufacturing. Desirably, most of the components are connected using ultrasonic bonding for improved manufacturing efficiency and reduced raw material costs. For example, in particular embodiments, the side seams[0108]54 are made using ultrasonic bonding. Certain garment manufacturing equipment which is readily known and understood in the art, including frames and mounting structures, ultrasonic and adhesive bonding devices, transport conveyors, transfer rolls, guide rolls, tension rolls, and the like, have not been shown in the Figures.
• It will be appreciated that details of the foregoing embodiments, given for purposes of illustration, are not to be construed as limiting the scope of this invention. Although only a few exemplary embodiments of this invention have been described in detail above, those skilled in the art will readily appreciate that many modifications are possible in the exemplary embodiments without materially departing from the novel teachings and advantages of this invention. For example, features described in relation to one embodiment may be incorporated into any other embodiment of the invention. Accordingly, all such modifications are intended to be included within the scope of this invention, which is defined in the following claims and all equivalents thereto. Further, it is recognized that many embodiments may be conceived that do not achieve all of the advantages of some embodiments, particularly of the preferred embodiments, yet the absence of a particular advantage shall not be construed to necessarily mean that such an embodiment is outside the scope of the present invention.[0109]

Claims (35)

What is claimed is:

1. A method of making a pant having side seams and hanging legs, comprising:

providing a flat web;

removing at least one portion of the flat web to define two leg openings;

contracting the flat web in at least one selected area to define at least one contracted area, a first region and a second region; and

attaching the first region and the second region together to form the side seams.

2. The method ofclaim 1, further including applying a strip in the at least one selected area.

3. The method ofclaim 2, wherein contracting the flat web in the at least one selected area comprises contracting the strip.

4. The method ofclaim 2, wherein the strip comprises a delayed retraction material.

5. The method ofclaim 1, wherein contracting the flat web in the at least one selected area comprises corrugating the flat web.

6. The method ofclaim 5, wherein corrugations are bonded together.

7. The method ofclaim 1, further comprising attaching at least one waist elastic to the flat web.

8. The method ofclaim 1, further comprising folding the flat web.

9. The method ofclaim 1, wherein the pant is made using a machine direction assembly.

10. The method ofclaim 1, wherein the pant is made using a cross-machine direction assembly.

11. The method ofclaim 1, further comprising cutting the flat web into separate pieces.

12. The method ofclaim 11, wherein the contracting occurs before the cutting.

13. The method ofclaim 11, wherein the contracting occurs after the cutting.

14. The method ofclaim 1, wherein the flat web comprises an integral elastic zone.

15. A method of making an absorbent pant having side seams and hanging legs, comprising:

providing a flat web;

removing at least one portion of the flat web to define two leg openings;

contracting the flat web in at least one selected area to define at least one contracted area, a first region and a second region;

attaching an absorbent structure to the flat web; and

attaching the first region and the second region together to form the side seams.

16. The method ofclaim 15, further including applying a strip in the at least one selected area.

17. The method ofclaim 15, wherein contracting the flat web in the at least one selected area comprises contracting the strip.

18. The method ofclaim 15, wherein the strip comprises a delayed retraction material.

19. The method ofclaim 15, wherein contracting the flat web in the at least one selected area comprises corrugating the flat web.

20. The method ofclaim 19, wherein corrugations are bonded together.

21. The method ofclaim 15, further comprising attaching at least one waist elastic to the flat web.

22. The method ofclaim 15, further comprising folding the flat web.

23. The method ofclaim 15, wherein the pant is made using a machine direction assembly.

24. The method ofclaim 15, wherein the pant is made using a cross-machine direction assembly.

25. The method ofclaim 15, further comprising cutting the flat web into separate pieces

26. The method ofclaim 25, wherein the contracting occurs before the cutting.

27. The method ofclaim 25, wherein the contracting occurs after the cutting.

28. The method ofclaim 15, wherein the flat web comprises an integral elastic zone.

29. A pant made from a single flat web, the pant comprising:

a garment shell, the garment shell including a front region, a back region, a contracted crotch region, side seams connecting the front region to the back region, and hanging legs, at least a portion of each of the front region, the back region, the contracted crotch region and the hanging legs comprising portions of the single flat web.

30. The pant ofclaim 29, further comprising a waist elastic extending along at least a portion of at least one of a front waist edge of the front region and a back waist edge of the back region.

31. The pant ofclaim 29, further comprising an absorbent structure attached to the garment shell in at least one of the front region, the back region and the crotch region.

32. The pant ofclaim 31 wherein the absorbent structure is attached to the garment shell by one of ultrasonic bonding and adhesive bonding.

33. The pant ofclaim 31, wherein the absorbent structure comprises a stretchable material.

34. The pant ofclaim 29, wherein a ratio of a take up to twice an inseam length is in a range from about 1:1 to about 1.5:1.

35. A method of making a pant having side seams and hanging legs, comprising:

providing a flat web;

removing at least one portion of the flat web to define two openings;

applying at least one strip to the flat web;

contracting the strip to provide at least one contracted area, a first region and a second region;

attaching the first region to the second region.

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