Patent Application
20120246915
The present disclosure relates to converting systems for manufacturing absorbent articles, and more particularly, to systems including a plurality of converting lines for producing taped diapers and pant diapers.
Disposable, reusable and durable products such as diapers, adult incontinence articles, feminine hygiene tampons, sanitary napkins, underpants, shirts, shorts, swimsuits, gowns, pants, coats, gloves, scarves, surgical drapes, bibs, blankets, sheets, pillow cases, etc. may be manufactured on high speed converting lines. Such converting lines may utilize a web-based carrier to which many source materials, whether in a continuous web or discrete pieces, are processed and/or attached to the web to create a finished product.
Although a converting line may allow for high speed production of a specific type of absorbent article, some converting lines may be inflexible in that line changes that would be required to accommodate the production of different types of products would be so time consuming and/or expensive as to be economically impractical. For instance, some converting lines are custom designed and built to make specific products within a narrow range of parameters and operating conditions. For example, converting lines may be custom designed to make only taped diapers, whereas other converting lines may be custom designed to make only pant diapers. Thus, such custom converting lines may be used to produce particular types of diapers, e.g. taped or pant, in certain markets in an effort to provide a good match with business needs. However, the large number of differences between converting lines designed to produce different products can place unwanted limitations on a manufacturer's ability to provide multiple product offerings in some markets.
In markets having consumer demand for both taped diapers and pant diapers, a manufacturer may be required to have separate converting lines, each custom designed to produce one of the two products, which may require duplicate process and engineering development. However, consumer demand of one or both of the products may not be high enough to justify the manufacturer's cost of developing and maintaining separate converting lines dedicated to each of the product types. For example, if the demand for pant diapers in a particular market is not high enough to justify the cost of a converting line that produces only pant diapers, the manufacture may decide not to offer pant diapers in the market. In such markets, the flexibility to produce both products on the same converting line and therefore produce the proper mix of product to meet the market needs may provide the most efficient and cost effective approach.
In some markets, disposable taped diapers are used for infants from birth to a point when infants begin potty training. As an alternative to taped diapers, disposable pant diapers may be desirable and useful products for children in the potty training stage. In yet other instances, the use of pant diapers may start at an earlier age than ages typically associated with potty training, and therefore, pant diapers may be used more like a taped diaper than a training pant. One difference between taped diapers and pant diapers is how the two products are delivered from the manufacturer to the consumer, i.e., packaged. In particular, both taped diapers and pant diapers can generally include an absorbent chassis having a liquid impervious outer cover, a liquid pervious body-side liner, and an absorbent structure. However, a taped diaper may not have a closed initial waist opening circumference or leg openings prior to being removed from the package, whereas the absorbent chassis and/or the side panels (when present) of a pant diaper may be pre-closed to form an initial waist opening circumference and two leg openings. Since the percentage of users that prefer taped diapers versus a pant style, pull-on, diaper varies market to market it may be advantageous for a manufacturer to have the flexibility to produce both a taped diaper and a pant, pull-on, diaper on the same converting line in any desired ratio to meet the needs to the intended market.
Some attempts have been made to create converting lines that are capable of producing more than one type of diaper, such as disclosed in U.S. Patent Publication No. 2007/0213678A1. However, such converting lines represent a mere conglomeration or assembly of different converting lines designed to build specific types of diapers. These converting lines may utilize a relatively low number of the same processes and machinery when producing different types of diapers. Thus, a relatively large number of different processes and machinery in such converting lines are either turned-on or turned-off depending on what type of diaper is being produced. As such, a converting line that includes a relatively large number of processes that may not be used when producing different types of diapers may result in excessive capital costs, require large amounts of space, require duplicative development, and require additional maintenance.
Thus, there remains a need to develop a converting system including a plurality of converting lines that are designed to produce specific types of diapers (e.g. pants or taped) while at the same time utilizing a substantial number of the same processes and machinery to produce either the range of diaper types resulting in greater efficiency and lower overall cost.
Aspects of the apparatuses and methods according to the present disclosure relate to a converting system including a plurality of apparatuses for the fabrication of absorbent articles. Some of the apparatuses may be designed to operate in a first configuration to produce a plurality of taped diapers. And some of the apparatuses may be designed to operate in a second configuration to produce a plurality of pant diapers. The apparatuses, whether designed to operate in the first configuration or the second configuration, utilize a substantial number of the same processes and machinery to produce taped diapers and pant diapers.
In one form, a converting system for the fabrication of absorbent articles may include: a first converting apparatus adapted to operate in a first configuration comprising a first plurality of transformation mechanisms, wherein the first plurality of the transformation mechanisms are arranged to produce a plurality of taped diapers, and wherein the first plurality of the transformation mechanisms produce a first number of transformations; a second converting apparatus adapted to operate in a second configuration comprising a second plurality of transformation mechanisms, wherein the second plurality of the transformation mechanisms are arranged to produce a plurality of pant diapers, and wherein the second plurality of the transformation mechanisms produce a second number of transformations; and wherein greater than 70% of the second number of transformations are the same as the first number of transformations.
In another form, a converting system for the fabrication of absorbent articles may include: a first converting apparatus adapted to operate in a first configuration comprising a first plurality of transformation mechanisms, wherein the first plurality of the transformation mechanisms are arranged to produce a plurality of taped diapers, and wherein the first plurality of the transformation mechanisms produce a first number of transformations, wherein the first number of transformations are carried out in a first sequence advancing from a first transformation to a last transformation; a second converting apparatus adapted to operate in a second configuration comprising a second plurality of transformation mechanisms, wherein the second plurality of the transformation mechanisms are arranged to produce a plurality of pant diapers, and wherein the second plurality of the transformation mechanisms produce a second number of transformations, wherein the second number of transformations are carried out in a second sequence advancing from a first transformation to a last transformation; and wherein 70% of the second number of transformations are carried out in an identical order as the first number of transformations with respect to one or more of preceding transformations in the first number of transformations.
The following term explanations may be useful in understanding the present disclosure:
“Absorbent article” is used herein to refer to consumer products whose primary function is to absorb and retain soils and wastes. “Diaper” is used herein to refer to an absorbent article generally worn by infants and incontinent persons about the lower torso. The term “disposable” is used herein to describe absorbent articles which generally are not intended to be laundered or otherwise restored or reused as an absorbent article (e.g., they are intended to be discarded after a single use and may also be configured to be recycled, composted or otherwise disposed of in an environmentally compatible manner).
The term “disposed” is used herein to mean that an element(s) is formed (joined and positioned) in a particular place or position as a macro-unitary structure with other elements or as a separate element joined to another element.
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 term “substrate” is used herein to describe a material which is primarily two-dimensional (i.e. in an XY plane) and whose thickness (in a Z direction) is relatively small (i.e. 1/10 or less) in comparison to its length (in an X direction) and width (in a Y direction). Non-limiting examples of substrates include a web, layer or layers or fibrous materials, nonwovens, films and foils such as polymeric films or metallic foils. These materials may be used alone or may comprise two or more layers laminated together. As such, a web is a substrate.
The term “nonwoven” refers herein to a material made from continuous (long) filaments (fibers) and/or discontinuous (short) filaments (fibers) by processes such as spunbonding, meltblowing, carding, and the like. Nonwovens do not have a woven or knitted filament pattern.
The term “machine direction” (MD) is used herein to refer to the primary direction of material flow through a process. In various manufacturing and converting processes, such as a bi-fold process, it may be possible to have more than one machine direction when an article is undergoing simultaneous processes. In other words, a manufacturing line may have an overall machine direction, but an article may travel in directions other than the overall machine direction as it passes through various processes along the manufacturing line. For example, an article having a trailing end portion and a leading end portion, each portion being attached to the surface of a different roll and/or conveyor, may travel in two different directions simultaneously. In this example, both directions of travel may be considered the machine direction. The term “cross direction” (CD) is used herein to refer to a direction that is generally perpendicular to the machine direction.
The term “transformation” refers herein to a change or activity resulting in a change in a web, layer, article, plurality of articles, material or portions thereof with regard to the thickness, length, width, shape, relative position, texture, color, tackiness, etc. Transformations are: fiberization, core component mixing, core formation/deposition, slitting, cutting, notching, shaping, perforation, die cutting, trimming, thermal bonding, ultrasonic bonding, pressure bonding, radio frequency bonding, seaming, adhesive application, cohesive application, lotion application, folding, bi-folding, tucking, spacing, MD positioning, CD positioning, registration, activation, compression, nipping, calendaring, substrate combining, component combining, web combining, elastic tensioning, fastening element pre-fastening, product stacking, and packaging.
The term “transformation mechanism” refers herein to an apparatus adapted to produce a transformation.
The term “taped diaper” (also referred to as “open diaper”) refers to disposable absorbent articles having an initial front waist region and an initial back waist region that are not fastened, pre-fastened, or connected to each other as packaged, prior to being applied to the wearer. A taped diaper may be folded about the lateral centerline with the interior of one waist region in surface to surface contact with the interior of the opposing waist region without fastening or joining the waist regions together. Example taped diapers are disclosed in various suitable configurations are disclosed in U.S. Pat. Nos. 5,167,897, 5,360,420, 5,599,335, 5,643,588, 5,674,216, 5,702,551, 5,968,025, 6,107,537, 6,118,041, 6,153,209, 6,410,129, 6,426,444, 6,586,652, 6,627,787, 6,617,016, 6,825,393, and 6,861,571.
The term “pant” (also referred to as “training pant”, “pre-closed diaper”, “diaper-pant”, and “pull-on diaper”) refers herein to disposable absorbent articles having a continuous perimeter waist opening and continuous perimeter leg openings designed for infant or adult wearers. A pant can be configured with a continuous or closed waist opening and at least one continuous, closed, leg opening prior to the article being applied to the wearer. A pant can be preformed by various techniques including, but not limited to, joining together portions of the article using any refastenable and/or permanent closure member (e.g., seams, heat bonds, pressure welds, adhesives, cohesive bonds, mechanical fasteners, etc.). A pant can be preformed anywhere along the circumference of the article in the waist region (e.g., side fastened or seamed, front waist fastened or seamed, rear waist fastened or seamed). Example diaper pants in various configurations are disclosed in U.S. Pat. Nos. 5,246,433; 5,569,234; 6,120,487; 6,120,489; 4,940,464; 5,092,861; 5,897,545; 5,957,908; and U.S. Patent Publication No. 2003/0233082.
The term “initial waist opening circumference” refers herein to the circumference of the waist opening at the time the pant is placed in the package and subsequently when it is removed from the package by the consumer.
The present disclosure relates to a converting system including a plurality of converting lines for manufacturing absorbent articles, and in particular, converting lines that are configured to produce taped diapers or pant diapers. As discussed in more detail below, an absorbent article converting line may include a combination of converting mechanisms that advance substrates and component materials through a manufacturing process. While advancing in the machine direction MD through the converting line, substrates may be modified and/or combined with the other substrates and/or discrete components to create a continuous length of absorbent articles. Various substrates can be used to construct various components of the absorbent articles, such as backsheets, topsheets, and absorbent cores. Exemplary descriptions of absorbent article components with respect to both taped diapers and pant diapers are provided below. At a downstream portion of the converting process, the continuous length of absorbent articles may be subjected to a final knife and cut to create separate and discrete absorbent articles. In addition, defective articles may be removed from the process by a rejection system. Articles that are not deemed to be defective may be subject to further processing steps, such as folding and packaging.
Aspects of the converting systems according to the present disclosure include a plurality of converting apparatuses and relate to converting apparatuses for the fabrication of absorbent articles and designed to operate in a first configuration or a second configuration. As discussed in more detail below, the converting apparatuses include transformation mechanisms adapted to produce a series of transformations. In the first configuration, a first plurality of the transformation mechanisms are arranged to produce a plurality of taped diapers, wherein the first plurality of the transformation mechanisms produce a first number of transformations. In the second configuration, a second plurality of the transformation mechanisms are arranged to produce a plurality of pant diapers, wherein the second plurality of the transformation mechanisms produce a second number of transformations. The converting apparatuses of the converting system, whether designed to operate in the first or second configurations, are designed such that greater than 70% of the second number of transformations are the same as the first number of transformations, resulting in greater efficiency and equipment utilization.
In another form, the first configuration may include a first plurality of transformation mechanisms adapted to produce a first number of transformations, wherein the first number of transformations may be carried out in a first sequence advancing from a first transformation to a last transformation. In addition, the second configuration may include a second plurality of the transformation mechanisms adapted to produce a second number of transformations. The second number of transformations may be carried out in a second sequence advancing from a first transformation to a last transformation. Again, the converting apparatuses are configured with a relatively large number of similarities between the first and second configurations, because 70% of the second number of transformations is carried out in an identical order as the first number of transformations with respect to one or more of preceding transformations in the first number of transformations.
The following provides a general description of various types of taped diapers and pant diapers that may be produced with the methods and apparatuses disclosed herein to help provide additional context to the subsequent discussion of the reconfigurable converting lines. For example,
Although pant and taped diapers may have distinct different features and components, it is to be appreciated that taped and pant diapers may include many features and components that are substantially the same or similar with regard to disposition, structure, dimension, physical appearance, etc. For the purposes of a specific illustration, various common components of taped and pant diapers shown in
As shown in
As shown in
With continued reference to
It is to also be appreciated that a portion or the whole of the diapers 100T and 100P may also be made laterally extensible. The additional extensibility may help allow the diapers 100T and 100P to conform to the body of a wearer during movement by the wearer. The additional extensibility may also help, for example, allow the user of the diaper 100T and 100P including a chassis 102 having a particular size before extension to extend the front waist region 116, the back waist region 118, or both waist regions of the diaper 100T and 100P and/or chassis 102 to provide additional body coverage for wearers of differing size, i.e., to tailor the diaper to an individual wearer. Such extension of the waist region or regions may give the absorbent article 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.
As previously mentioned, the taped and pant diapers 100T and 100P may include a backsheet 136. The backsheet 136 may also define the outer surface 134 of the chassis 102. The backsheet 136 may be impervious to fluids (e.g., menses, urine, and/or runny feces) and may be manufactured from a thin plastic film, although other flexible liquid impervious materials may also be used. The backsheet 136 may prevent the exudates absorbed and contained in the absorbent core from wetting articles which contact the diaper 100T and 100P, such as bedsheets, pajamas and undergarments. The backsheet 136 may also comprise a woven or nonwoven material, polymeric films such as thermoplastic films of polyethylene or polypropylene, and/or a multi-layer or composite materials comprising a film and a nonwoven material (e.g., having an inner film layer and an outer nonwoven layer). The backsheet may also comprise an elastomeric film. An example backsheet 140 may be a polyethylene film having a thickness of from about 0.012 mm (0.5 mils) to about 0.051 mm (2.0 mils). Exemplary polyethylene films are manufactured by Clopay Corporation of Cincinnati, Ohio, under the designation BR-120 and BR-121 and by Tredegar Film Products of Terre Haute, Ind., under the designation XP-39385. The backsheet 136 may also be embossed and/or matte-finished to provide a more clothlike appearance. Further, the backsheet 136 may permit vapors to escape from the absorbent core (i.e., the backsheet is breathable) while still preventing exudates from passing through the backsheet 136. The size of the backsheet 136 may be dictated by the size of the absorbent core 142 and/or particular configuration or size of the diaper 100T and 100P.
Also described above, the taped and pant diapers 100T and 100P may include a topsheet 138. The topsheet 138 may also define all or part of the inner surface 132 of the chassis 102. The topsheet 138 may be compliant, soft feeling, and non-irritating to the wearer's skin. It may be elastically stretchable in one or two directions. Further, the topsheet 138 may be liquid pervious, permitting liquids (e.g., menses, urine, and/or runny feces) to penetrate through its thickness. A suitable topsheet 138 may be manufactured from a wide range of materials such as woven and nonwoven materials; apertured or hydroformed thermoplastic films; apertured nonwovens, porous foams; reticulated foams; reticulated thermoplastic films; and thermoplastic scrims. Suitable woven and nonwoven materials may comprise natural fibers such as wood or cotton fibers; synthetic fibers such as polyester, polypropylene, or polyethylene fibers; or combinations thereof. If the topsheet 138 includes fibers, the fibers may be spunbond, carded, wet-laid, meltblown, hydroentangled, or otherwise processed as is known in the art.
Topsheets 138 may be selected from high loft nonwoven topsheets, apertured film topsheets and apertured nonwoven topsheets. Apertured film topsheets may be pervious to bodily exudates, yet non-absorbent, and have a reduced tendency to allow fluids to pass back through and rewet the wearer's skin. Example apertured films may include those described in U.S. Pat. Nos. 5,628,097; 5,916,661; 6,545,197; and 6,107,539.
As mentioned above, the taped and pant diapers 100P and 100T may also include an absorbent assembly 140 that is joined to the chassis 102. As shown in
Some absorbent core embodiments may comprise fluid storage cores that contain reduced amounts of cellulosic airfelt material. For instance, such cores may comprise less than about 40%, 30%, 20%, 10%, 5%, or even 1% of cellulosic airfelt material. Such a core may comprises primarily absorbent gelling material (AGM) in amounts of at least about 60%, 70%, 80%, 85%, 90%, 95%, or even about 100%, where the remainder of the core comprises a microfiber glue (if applicable). Such cores, microfiber glues, and absorbent gelling materials are described in U.S. Pat. Nos. 5,599,335; 5,562,646; 5,669,894; and 6,790,798 as well as U.S. Patent Publication Nos. 2004/0158212 and 2004/0097895.
As previously mentioned, the taped diapers 100T and pant diapers 100P may also include elasticized leg cuffs 156 and an elasticized waistband 158. It is to be appreciated that the leg cuffs 156 can be and are sometimes also referred to as leg bands, side flaps, barrier cuffs, elastic cuffs or gasketing cuffs. The elasticized leg cuffs 156 may be configured in various ways to help reduce the leakage of body exudates in the leg regions. Example leg cuffs 156 may include those described in U.S. Pat. Nos. 3,860,003; 4,909,803; 4,695,278; 4,795,454; 4,704,115; 4,909,803; and U.S. Patent Publication No. 2009/0312730A1.
The elasticized waistband 158 may provide improved fit and containment and may be that portion or zone of the diaper 100T and 100P that may elastically expand and contract to dynamically fit a wearer's waist. The elasticized waistband 158 may extend longitudinally inwardly from the waist edges 120, 122 of the diaper toward the lateral edges 148, 150 of the absorbent core 142. The diaper 100T and 100P may also include two elasticized waistbands 158, one positioned in the back waist region 118 and one positioned in the front wait region 116, although other embodiments may be constructed with a single elasticized waistband 158. The elasticized waistband 158 may be constructed in a number of different configurations including those described in U.S. Pat. Nos. 4,515,595 and 5,151,092.
The elasticized waistbands 158 may include materials that have been “prestrained” or “mechanically prestrained” (i.e., subjected to some degree of localized pattern mechanical stretching to permanently elongate the material). The materials may be prestrained using deep embossing techniques as are known in the art. In some embodiments, the materials may be prestrained by directing the material through an incremental mechanical stretching system as described in U.S. Pat. No. 5,330,458. The materials are then allowed to return to their substantially untensioned condition, thus forming a zero strain stretch material that is extensible, at least up to the point of initial stretching. Examples of zero strain materials are disclosed in U.S. Pat. Nos. 2,075,189; 3,025,199; 4,107,364; 4,209,563; 4,834,741; and 5,151,092.
As shown in
As previously mentioned, pant and taped diapers may have distinct different features and/or components. And the following provides a general discussion of some such features and components with reference to accompanying figures showing embodiments of taped and pant diapers.
Taped diapers may be manufactured and provided to consumers in a configuration wherein the front waist region and the back waist region are not fastened, pre-fastened, or connected to each other as packaged, prior to being applied to the wearer. As shown in
The taped diaper 100T may include various configurations of fastening elements to enable fastening of the front waist region 116 and the back waist region 118 together to form a closed waist circumference and leg openings once the diaper is positioned on a wearer. For example, as shown in
The first fastening component 162 and/or the second fastening component 164 may include various types of releasably engageable fasteners. The first and second fastening components 162 and/or 164 may also include various types of refastenable fastening structures. For example, the first and second fastening components 162 and 164 may include mechanical fasteners, 166, in the form of hook and loop fasteners, hook and hook fasteners, macrofasteners, buttons, snaps, tab and slot fasteners, tape fasteners, adhesive fasteners, cohesive fasteners, magnetic fasteners, hermaphrodidic fasteners, and the like. Some examples of fastening systems and/or fastening components 162, 164 are discussed in U.S. Pat. Nos. 3,848,594; 4,662,875; 4,846,815; 4,894,060; 4,946,527; 5,151,092; 5,221,274; 6,251,097; 6,669,618; 6,432,098; and U.S. Patent Publication Nos. 2007/0078427 and 2007/0093769.
As previously mentioned, the fastening components 162 and 164 may be adapted to releasably and/or refastenably engage or connect with another portion of the diaper 100T. For example, as shown in
The taped diaper 100T may further include a non-engagement zone disposed on the same surface and in the same waist region as the fastening components 166. The non-engagement zone may be configured to help prevent the fastening component 166 from becoming engaged with other elements of the absorbent article. The non-engagement zone may comprise a film, coating or other material that does not attach to or engage with the fastening component 166. In certain embodiments the non-engagement zone is in surface to surface contact with the fastening surface of the fastening component when the taped diaper 100T is packaged.
In contrast to taped diapers, pant diapers may be manufactured and provided to consumers in a configuration wherein the front waist region and the back waist region are fastened, pre-fastened, or connected to each other as packaged, prior to being applied to the wearer. As such pant diapers may have a continuous perimeter waist opening and continuous perimeter leg openings designed for infant or adult wearers. As discussed in more detail below, a diaper pant can be preformed by various techniques including, but not limited to, joining together portions of the diaper using refastenable and/or permanent closure members (e.g., seams, heat bonds, pressure welds, adhesives, cohesive bonds, mechanical fasteners, etc.). In addition, pant diapers can be preformed anywhere along the circumference of the waist region (e.g., side fastened or connected, front waist fastened or connected, rear waist fastened or connected).
In some embodiments, pant diapers may be configured with side panels connected with the chassis in one or both of the waist regions. For example,
As previously mentioned and with reference to
It is to be appreciated that the either or both the distal and proximal regions of one or both the side panels 114 and 116 may be connected with the chassis in various ways. For example, in some configurations, the side panels are permanently connected with opposing waist regions and cannot be refastened once broken forming the leg and waist openings. Such permanent seams are pre-closed to provide a product that looks like underwear and can be applied like underwear, i.e. pulled-on. Disposable pant diapers with permanent seams may require a separate element for disposal such as a disposal tape disposed on the outer surface of the article. Other disposable pant diapers may have non-permanent seams and may be refastenable allowing the caregiver to open the initial waist opening circumference and leg openings and reclose them to facilitate application similar to a traditional tape style diaper. As such, the proximal regions and/or distal regions of the side panels may be permanently bonded, releasably connected, and/or refastenably connected with the chassis 102, with for example, adhesives, cohesives, thermal bonding, ultrasonic bonding, mechanical bonding and mechanical fastening e.g. hook and loop type fasteners. For example, one or more fastener elements may be located on or form a portion of the side panels and may be adapted to refastenably connect with one or more corresponding fastening elements located in the first or second waist regions or alternatively the fastener elements may be adapted to refastenably connect with one or more components of the absorbent article including the side panels. The diaper pant 100P can also include other features such as elastically extensible side panels that may each include one or more pieces of material. It should be appreciated that the side panels may also be formed as continuous extensions of the first and second waist regions of the chassis.
The ability to refasten an initially pre-fastened pant diaper may offer convenience to the caregiver. In some instances, it may be more convenient to apply the absorbent article like a traditional tape style diaper when away from home or when it is inconvenient to remove the clothing and/or shoes. Because it is difficult to predict when a change will be necessary and therefore when a particular mode of application will be needed, it is beneficial to have a disposable pant diaper that is adaptable to being applied either as a traditional tape style diaper or as a disposable pant diaper, pull-on. In addition, an absorbent article that can be applied like a traditional tape style diaper or a disposable pant diaper also permits inspection of the interior of the product without having to pull the product down. These refastenable structures may also provide dual functionality enabling the wrapping and disposal of the used product.
As previously mentioned, the side panels on pant diapers can be configured in different ways. Although the side panels 112 and 114 shown in
It is to be appreciated that the proximal regions of the ear panels of
It should also be appreciated that the side panels in one waist region may have the same lateral extent from the side edge of the chassis to the distal edge of the side panel as the longitudinally opposed side panels in the opposite waist region or alternatively the side panels disposed in a first waist region may have different lateral extent as measured from the side edge of the chassis to the distal edge of the side panel than the side panels disposed in a second waist region.
As such, for a pant diaper including side seams, a first portion of the pant diaper 100P adjacent the first side edge 128 in the front waist region 116 and a second portion of the pant diaper adjacent the first side edge 128 in the back waist region 118 may be connected to form a first permanent side edge seam 178. And a third portion of the pant diaper 100P adjacent the second side edge 130 in the front waist region 116 and a fourth portion of the pant diaper adjacent the second side edge 130 in the back waist region 118 may be connected to form a second permanent side edge seam 180. The connection of the side edge seams 178 and 180 define the initial waist opening 170 circumference and a pair of leg openings 172. In another configuration, a pant diaper 100P may include a first mating fastening component having a fastening surface and an opposing attachment surface wherein the attachment surface is joined directly to one of the interior or exterior surface of the pant diaper in a first waist region. The pant diaper may further comprise a second mating fastening component having a fastening surface and an opposing attachment surface wherein the attachment surface may be joined directly to the same surface of the pant diaper as the first fastening component. The second mating fastening component may be joined to or may form a portion of the surface to which the attachment surface of the first mating fastening component is joined.
In yet another configuration, the pant diaper may include a frangible separation zone that may be disposed laterally inward of the side edge seams 178 and 180 that allows the initial waist opening circumference 170 and leg openings 172 of the pant 100P to be opened for removal or to enable application as a traditional tape style diaper. As discussed above, the pant diaper may further include a first fastening component and a second fastening component disposed in one of the front or back waist regions 116 and 118. And each of the fastening components may be disposed on the same surface of the pant diaper 100P, e.g., the exterior surface 134. The fastening components may be capable of being fastened in a traditional tape style diaper fashion or fastened to reform a secondary waist opening circumference and leg openings after the initial waist opening circumference and leg openings have been broken. In addition, the fastening components can be used to aid disposal of a soiled pant.
As previously mentioned, the bonds of the side edge seams 178 and 180 may be permanent and can be formed in various ways appropriate for the specific materials employed. Thus, example bond types may include discrete bonds such as sonic sealed bonds, heat sealed bonds, high pressure bonds, radio frequency bonds, adhesive or cohesive bonds, sewed bonds, autogeneous bonds, and combinations thereof. In accordance with one aspect of the disclosure, the permanent side edge seams 178 and 180 may be joined by a predetermined pattern of heat/pressure or ultrasonic welds which withstands the forces and stresses exacted onto the side edge seam 51 during application and wear of the pant 20. The permanent side edge seams 178, 180 may be formed as disclosed in U.S. Pat. Nos. 5,779,831; 5,772,825; 5,607,537; 5,622,589; 5,662,638; 6,042,673; and 6,726,792.
Because the pant diaper 100P may be configured with permanent side edge seams 178 and 180, both permanent side edge seams may be pre-closed, meaning that the side edge seams are closed prior to removal of the diaper pant from its package, and therefore prior to being donned on the wearer. The pre-closed permanent side edge seams 178 and 180 may form an initial waist opening circumference and leg circumferences. The initial waist opening circumference and leg circumferences may be opened at predetermined frangible separation zones. The permanent side edge seams cannot be reclosed to form the secondary waist opening circumference and leg openings.
Additionally, various diaper pant configurations are disclosed in U.S. Pat. Nos. 5,246,433; 5,569,234; 6,120,487; 6,120,489; 4,940,464; 5,092,861; 5,897,545; 5,957,908; and U.S. Patent Publication Nos. 2003/0233082; 2005/0234419; 2003/0088220; 2005/0130821; 2003/0233082; 2005/0215971; 2005/0215970; 2007/0078427; 2007/0093769; 2007/0074381; 2007/0078426; and 2008/0107861.
As previously discussed, the converting system of the present disclosure may include a plurality of converting apparatuses and methods for manufacturing taped and pant diapers. And the converting apparatuses according to the present disclosure are configured to operate a first configuration or a second configuration. The converting apparatuses include transformation mechanisms adapted to produce a series of transformations. In a first configuration, a first plurality of the transformation mechanisms are arranged to produce a plurality of taped diapers, wherein the first plurality of the transformation mechanisms produce a first number of transformations. In a second configuration, a second plurality of the transformation mechanisms are arranged to produce a plurality of pant diapers, wherein the second plurality of the transformation mechanisms produce a second number of transformations. As discussed in more detail below with reference to
It is to be appreciated that one or more transformations may occur during each process step shown in
In other examples, such as shown in
Referring back to
As previously mentioned, the core assembly process 1002 may include a number of different transformations. It is to be appreciated that these transformations may be dependent on the actual composition of the absorbent materials forming the absorbent core. For example, heterogeneous absorbent cores comprising a blend a fibrous material and a particulate material may be formed by a blending transformation that blends, mixes or combines the fibrous component and a particulate component to form a heterogeneous absorbent structure. Examples of such heterogeneous structures may include blends of cellulosic fibers and absorbent gelling material wherein the cellulosic material may be present in a percentage from about 5% to about 95% and the absorbent gelling material present a percentage from about 95% to about 5% respectively. In some embodiments, the heterogeneous structure may comprise a blend of adhesive fibers and absorbent gelling material wherein the adhesive fibers are present in a percentage from about 2% to about 70% and the absorbent gelling material is present in a percentage from about 98% to about 30% respectively. In such embodiments, the cellulosic fibrous material may be supplied to the production line in bale form and/or in drylap form. Both of these forms may require a fiberization step to separate the fibers into individual fibers or small groupings of fibers to facilitate blending/mixing of the fibers with other materials. The absorbent gelling material may be supplied to the production line in particulate form and no further manipulation is required prior to formation of the heterogeneous structure. The individual fibers or small groupings of fibers may be mixed with the absorbent gelling material to form a heterogeneous mixture. The mixture may also be deposited onto a vacuum conveyance such as a vacuum belt or a vacuum drum to form either a continuous web of absorbent material or alternatively a plurality of discrete absorbent cores. The formation of the heterogeneous fiber AGM absorbent core material therefore may include at least three distinct transformations as detailed herein above; fiberization, mixing and deposition.
It is to be appreciated that formation of an absorbent core from a material that is supplied to the production line in roll form is also possible. Examples of such web form absorbent materials include tissue laminates (laminates of tissue and absorbent gelling material), nonwoven laminates (laminates of nonwoven and absorbent gelling material), absorbent foams, high basis weight absorbent tissues, absorbent wadding, thermally bonded cellulosic fiber and absorbent gelling material composites, chemically bonded cellulosic fiber and absorbent gelling material composites and the like. The material may simply be unwound and subsequently severed in the cross machine direction at the desired machine direction length. The material may also be severed in the machine direction, either linearly or in a shaped pattern such as a repeating nested pattern. The cross machine direction cutting and/or the machine direction cutting and/or shaping may also form specific transformation steps as described herein.
The following provides additional explanation of “unwinding,” which may be a part of various process assemblies used in the converting line 300T shown in
With further regard to unwinding, some materials may be supplied to the production line in the form of composite web, i.e. a web comprising two or more distinct layers or structures, disposed in roll form. Examples of such web materials include composites of films and nonwovens, including polymeric films, elastomeric films, microporous films, monolithic films and the like combined with woven and/or nonwoven materials, such as carded and/or spunbond materials comprising polymeric fibers such as polyethylene, polypropylene and the like. This type of unwind may also comprise a splicing feature. The material splicing feature forms transformations, i.e., splicing (e.g., bonding). If the splicing step includes a cutting step, the cutting step may form a separate transformation.
In addition, materials such as elastics may be supplied to a production line in the form of a film or a continuous strand disposed on a roll or spool. Examples of such strand materials include: lycra elastics, natural rubber elastics, threads, strings and the like. The materials may be delivered to the production line by means of a material unwind. The material unwind may comprise guides to properly space the strands and provide proper orientation of the strand relative to the absorbent article. The unwind may also comprise a tensioning device, metering control, which adds tension to the film or strand which in the case of an elastic extends the elastic thereby controlling the elastic contraction force once applied to the article. In some instances, the production line is stopped to splice in new rolls of strand materials. These materials, in particular, strand materials may have an extremely long run time and therefore the stoppage required for changeover may have a minimal impact on the efficiency of the converting process. A material unwind comprising a tensioning device may form a transformation.
The following provides additional explanation of the transformations referred to as “spacing,” which may be a part of various process assemblies used in the converting line 300T shown in
The following provides additional explanation of the transformations referred to as “adhesive application,” and “bonding,” which may be a part of various process assemblies used in the converting line 300T shown in
It is to be appreciated that many forms of bonding may be used to create a bond within a specific element for example bonding two layers of a folded element together or alternatively to attach two or more elements of an absorbent article together. For example, thermal bonding may be used to create such bonds. There are several specific types of thermal bonds including thermal bonds resulting from direct application of heat, thermal bonds generated by sonic waves for example, ultrasonic bonds and pressure bonds which generate heat by means of pressure. A thermal bond may be present in one position on the absorbent article or may be present in laterally or longitudinally opposing pairs. In embodiments wherein laterally or longitudinally opposing pairs of thermal bonds are present the pairs of bonds and the equipment used to create the pairs of bonds may form a transformation. In embodiments comprising multiple thermal bonds for example a continuous pattern of thermal bonds extending the length and/or the width of the absorbent article the equipment used to create such a continuous pattern of thermal bonds may form a transformation.
Although not specifically recited in the process steps shown in
The activation approaches described herein may be achieved by using a set, two or more, intermeshing opposing rolls comprising a staggered orientation of teeth such that when a material such a single web or composite web of material passes through the intermeshing rolls, at least a portion of the material is partially deformed to create the desired activation pattern in the web. The teeth of one or more of the rolls may be continuous around the circumference of the roll while the teeth on one or more of the intermeshing opposing rolls may be discontinuous forming intermittent activation (e.g., a structured elastic-like formed web) or a pitched continuous activation (e.g., continuously activated in the opposing waist regions and not the crotch region). One such process for activating materials to provide extensibility is described in U.S. Pat. No. 5,518,801 issued on 21 May 1996 in the name of Chappell et al. The depth to which the teeth intermesh, i.e., depth of engagement, will determine to what degree the web is incrementally stretched and/or plastically deformed and therefore the degree of extensibility imparted to the web. In some embodiments, the absorbent article can be activated in a portion of the backsheet, the waist region, the waistband, the side panels and or the leg cuffs for example, to provide additional extensibility.
In some embodiments, a portion of the absorbent article may be continuously activated meaning that the teeth of two or more of the rolls may be continuous around the circumference of the roll while forming continuous activation (e.g., ring-rolled and thus rendered highly extensible as described in U.S. Pat. No. 5,366,782 (issued Nov. 22, 1994 to Curro, et al.)). Specifically, a ring-rolling apparatus which comprises opposing rolls having intermeshing teeth that incrementally stretch and thereby plastically deform the chassis (or a portion thereof) thereby rendering the chassis extensible in the ring-rolled regions. In some embodiments, the side panels that form a portion of at least one of the front and/or back waist regions may be activated by ring rolling while other regions of the absorbent article remain unactivated or are activated to form a structured elastic-like formed web material.
The converting methods and apparatuses herein may include various types of mechanisms to perform the folding transformation 2010 shown in
The method of operation of the folding apparatus 302 may be described with reference to the figures herein and in the context of a method for folding articles, such as taped diapers or pant diapers. The following provides various term explanations that may be useful in understanding the present discussion of the folding apparatus 302. “Leading end portion” means that portion of an absorbent article prior to bi-folding that is disposed forward of the fold line in the machine direction. “Trailing end portion” refers to that portion of an absorbent article prior to bi-folding that is disposed after the fold line in the machine direction. “Fold line” means the portion of an article about which the article is intended to be bi-folded. The fold line typically extends from one longitudinal edge to the other longitudinal edge in the lateral direction. In certain embodiments, the fold line may correspond to the lateral centerline of the article. “Bi-fold” means the leading edge portion and the trailing edge portion of an article on a production line are brought together in a face-to-face configuration along a fold line as the article moves in the machine direction of travel. “Holding an article to the surface of a roll” means employing a holding force to one or more portions of an article in order to join the article at least temporarily to the surface of a roll such that the article is inhibited from traveling in a direction substantially orthogonal to the surface of the roll without reducing or removing the holding force and/or employing a peel-force. This definition is equally applicable to conveyors, e.g., the bi-fold conveyor assembly described herein below. “Peel force” means the force applied to an object in a direction that is substantially perpendicular to the plane of the surface in which the object lies or on which the object rests. A force applied in a direction within 45° of the perpendicular direction may be considered a peel force. “Shear force” means the force applied to an object in a direction that is substantially parallel to the plane of the surface in which the object lies or on which the object rests. A force applied in a direction within 45° of the parallel direction may be considered a shear force.
As shown in
With the leading end portion of the diaper 100T and 100P engaged with the peel roll 308, the trailing end portion 202 of the diaper 100T and 100P remains on the rotating folding drum 306. As the folding drum 306 continues to rotate, clamps from the folding drum may operate to hold diaper 100T and 100P onto the folding drum 306 and the clamped portion of the diaper 100T and 100P continues to move with the folding drum outer surface. When the clamps reach a particular position relative to the peel roll 308, the clamps may exert a force such as, for example, a shear force on the leading end portion 200. The shear force exerted on the leading end portion 200 may be in a direction that is substantially different from or even opposite the direction of travel of the outer surface of the peel roll 308. Thus, the leading end portion 200 may begin to slow down and/or even stop moving. As the leading portion 200 decelerates and/or stops moving, the leading end portion 200 of the diaper 100T and 100P is transferred from the peel roll 308 to a vacuum conveyor 310 including a movable surface. And the movable surface of the vacuum conveyor is accelerated to a surface speed equal to or substantially equal to the surface speed of the folding drum. Next, the garment facing surface 132 of the leading end portion 200 of the diaper 100T and 100P is transferred along the vacuum conveyor and the leading end portion is brought into surface to surface contact with the trailing end portion 202 of the diaper 100T and 100P on the folding drum 306.
It is to be appreciated that the folding apparatus can be configured in accordance with and may include various other features described in U.S. Patent Publication Nos. 2009/0094941A1 and 2009/0098995A1; as well as U.S. patent application Ser. No. 13/051,210, entitled “Apparatuses and Methods for Folding an Absorbent Article,” and filed on Mar. 18, 2011.
The taped converting apparatus 300T is shown in
As mentioned above with respect to
Although many of the processes and associated transformations may remain unchanged between the taped diaper configuration 300T shown in
As shown in
As shown in
As shown in
When the folded pant diapers 100P advance from the folding transformation 2010 and through the side panel connection transformation 2012, the distal end regions 176 of the laterally extending side panels 112 and 114 are connected with another portion of the pant diaper 100P. For example, the proximal end regions 174 of the side panels 112 and 114 such as shown in
It is to be appreciated that various types of transformation mechanisms may be used to carry out the side panel connection 2012. For example, a twisted conveyor arrangement, such as shown in
As shown in
As shown in
As the diaper pant 100P advances in the machine direction through the tucking zone, the opposing vacuum forces exerted by the first and second conveyors 502 and 504 may continue to hold the chassis or may be removed from the chassis. And a side panel tucker 516 pushes the side panels 112 and 114 into the chassis 102, such as shown for example in
It is to be appreciated that side panel tuckers 516 may be configured in various different ways. For example, as shown in
Once the side panels 112 and 114 are pushed into the chassis 102, the diaper pant 100P may continue to advance on the first conveyor 502 in the machine direction. The waist regions 116 and 118 of the diaper pant 100P may also be further compressed together to help hold the side panels 112 and 114 in the tucked position, such as with conveyors that converge toward each other in the machine direction.
It is to be appreciated that the pant converting apparatus 300P can be designed to operate in other configurations to manufacture diaper pants having various other features. For example,
As mentioned above with respect to
Although many of the processes and associated transformations may remain unchanged between the taped diaper configuration 300T shown in
As shown in
As discussed above with reference to
As shown in
When the folded pant diapers 100P advance from the folding transformation 2010 and through the side panel connection transformation 2012, the distal end regions 176a of the laterally extending front ear panels 112a and 114a are connected with the distal end regions 176b of the rear ear panels 112b and 114b, such as shown for example in
It is to be appreciated that the laterally opposing side seams 178, 180 may be disposed at or adjacent the side edge 128, 130 in one or both waist regions 116, 118. In embodiments wherein the lateral extent of the front waist region 116 is substantially equal to the lateral extent of the back waist region 118 during bonding of the permanent side edge seams 178, 180, the side edge seams may be disposed at or adjacent the side edges of the absorbent article in both the front and back waist regions. In the embodiment, the absorbent article is folded at a laterally extending fold line disposed in the crotch region to bring the front waist region and the back waist region into an interior surface to interior surface face to face orientation. The permanent side edge seams are formed by placing the interior surface of one waist regions in an overlapping relationship with the exterior surface of the opposing waist region adjacent the side edges and subsequently bonding the waist regions together. The first fastening component may be applied to the article prior to forming the permanent side edge seam. The second fastening component may also be applied prior to forming the permanent side edge seam or after forming the permanent side edge seam. In this embodiment, the first fastening component and the non-engagement surface are disposed at least partially within the permanent side edge seam with the fastening surface of the first fastening component in a face to face surface to surface orientation with the non-engagement surface. As removed from the package, the absorbent article is in the form of a pant. The user may apply the absorbent article to the wearer as a pant or alternatively the user may apply the absorbent article as a taped diaper by first releasing the fastening component by separating the front waist region from the back waist region by breaking the permanent side edge seam thereby opening the initial waist opening circumference, then placing the back waist region of the article under the wearer and fastening the first fastening component to the second fastening component to reclose the pant on the wearer.
It is to be appreciated that based on the foregoing discussion, converting systems of the present disclosure may include a plurality of converting apparatuses and methods for manufacturing taped and pant diapers, such as the converting mechanisms 300T, 300P discussed above with reference to
In order to make two different product types, for example pant diapers and taped diapers, on converting lines comprising similar transformations, such as taped diaper converters 300T and pant diaper converters 300P, it may be important to maintain the line speeds for each of the product types within a specified operating line speed range. The converting lines are typically comprised of multiple transformations each of which may have a centerline defining its optimum operating condition and an operating range around the centerline where the transformation can operate without significant changes or modifications. Therefore, producing both taped and pant products on lines having common transformations requires a specific operating range derived as a function of overall line speed, products per minute. The following ranges have been established for products having a pitch length, length of the product along the longitudinal centerline, of between 480 mm to 550 mm. It should be understood that for a given linear speed the line speed, products per minute, will increase for shorter products and decrease for longer products.
For processes wherein one of the taped or pant diaper products is produced at a first line speed of less than 800 products per minute, the operating line speed range for the other product is defined as the first line speed +/−50%. In other words if a taped diaper is made at 500 products per minute then the pant diaper must be produced at a speed of between 250 products per minute and 750 products per minute. Preferably if the processes wherein one of the taped or pant diaper products is produced at a first line speed of less than 800 products per minute, the operating line speed range for the other product is defined as the first line speed +/−25%. In other words if a taped diaper is made at 600 products per minute then the pant diaper must be produced at a speed of between 450 products per minute and 750 products per minute.
For processes wherein one of the taped or pant diaper products is produced at a first line speed of between 800 and 960 products per minute, the operating line speed range for the other product is defined as the first line speed +/−30%. In other words if a taped diaper is made at 900 products per minute then the pant diaper must be produced at a speed of between 630 products per minute and 1170 products per minute. Preferably if the processes wherein one of the taped or pant diaper products is produced at a first line speed of between 800 and 960 products per minute, the operating line speed range for the other product is defined as the first line speed +/−10%. In other words if a taped diaper is made at 900 products per minute then the pant diaper must be produced at a speed of between 810 products per minute and 990 products per minute.
For processes wherein one of the taped or pant diaper products is produced at a first line speed of greater than 960 products per minute, the operating line speed range for the other product is defined as the first line speed +/−20%. In other words if a taped diaper is made at 1000 products per minute then the pant diaper must be produced at a speed of between 800 products per minute and 1200 products per minute. Preferably if the processes wherein one of the taped or pant diaper products is produced at a first line speed of greater than 960 products per minute, the operating line speed range for the other product is defined as the first line speed +/−5%. In other words if a taped diaper is made at 1000 products per minute then the pant diaper must be produced at a speed of between 950 products per minute and 1050 products per minute.
Maintaining the process or processes within the desired operating line speed range may help simplify converting line development since each of the multiple transformations needs to only be developed for one type of product and subsequently can be reapplied to the second type of product.
It is to be appreciated that various types of pant and taped diapers may be constructed in accordance with the aforementioned methods and apparatuses. As such, embodiments of such apparatuses and methods may be configured to construct pant and taped diapers having some elements that are configured with specified ranges of performance parameters.
In some embodiments, pant and taped diapers having inner leg cuffs may be constructed in accordance with the above-described methods and apparatuses, wherein the inner leg cuffs are configured to have a range of force characteristics, as described below. In one form, such as shown in
As shown in
As shown in
A cross section of the sample is shown in
The inner cuff specimen is tested according to the method for Inner Cuffs in the Cuff Tensile Test described in the Test Methods section below. In one embodiment of an inner cuff specimen that may be applied to a taped or pant diaper, the force value on the 2nd unload cycle at 85% extension may be between 0.25 N and 0.45 N and/or the strain value at 0.05 N on the 2nd unload cycle may be between 50% and 75%.
In some embodiments, pant and taped diapers having outer leg cuffs may be constructed in accordance with the above-described methods and apparatuses, wherein the outer leg cuffs are configured to have a range of force characteristics, as described below. In one form, such as shown in
An adhesive 710 (Bostik H2031) is applied in a spiral pattern at a basis weight of 11 g/m2 uniformly in an area 712 defined by dimension, N, in the cross direction and by dimension, O, in the machine direction (a mask may be used to obtain the desired adhesive area), or alternatively the adhesive 712 may be applied to silicone-coated release paper and transferred to the nonwoven 700 at room temperature after cutting the appropriate sized piece. In some embodiments, dimension N may be 15 mm, and dimension O may be 276 mm. The adhesive area 712 is aligned so a first longitudinal edge 714 is located a distance, P, from the first machine direction edge 702 of the nonwoven 700 and a first lateral edge 716 is offset a distance, Q, from the first cross direction edge 706, as shown in
A suitable breathable backsheet film 800 layer with a basis weight of 16 g/m2 such as a MicroPro™ Microporous Film available through Clopay Plastic Products is cut with a CD width dimension, S, and a MD length dimension, T, shown in
The outer cuff is tested according to the method for Outer Cuffs in the Cuff Tensile Test described in the Test Methods section below. The force value on the 2nd unload cycle at 85% extension may be between 0.35 N and 1.0 N and/or the strain value at 0.05N on the 2nd unload cycle may be between 60% and 80%.
In still another form, pant diapers having waist openings may be constructed in accordance with the above-described methods and apparatuses, wherein the waist openings are configured to have a range of force characteristics that may be measured according to the Waist Stretch Test (Pants) recited below. In some embodiments, the waist hoop length at 2000 gf may be between 200 and 800 mm; may be between 500 and 700 mm; and may be from 550 to 670 mm and the unload force at a waist hoop length of 530 mm may be between 250 and 2000 gf; may be between 300 and 1500 gf; and may be between 350 and 1150 gf.
In yet another form, taped diapers having back ears may be constructed in accordance with the above-described methods and apparatuses, wherein the back ears are configured to have a range of force characteristics that may be measured according to the Waist Stress-Relaxation Test (Taped Diapers) recited below. In some embodiments, the elongation values at 4N force during the loading cycle may be between 30 mm and 110 mm; may be between 50 mm and 100 mm; and may be between 70 mm and 90 mm. The elongation values at 10N force during the loading cycle may be between 60 mm and 180 mm; may be between 100 mm and 165 mm; and may be between 135 mm and 150 mm. The force at 60 minutes, F60, after reaching the maximum elongation as described below according to Step 2 of the Waist Stress-Relaxation Test (Taped Diapers) may be greater than 45% of the maximum force, Fmax, which may be measured at the maximum elongation.
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 grips that are at least as wide as the width of specimens to be tested, lined with one rubber-coated face and one contact line face for both upper and lower grips. A load cell is used so that the maximum load measured is within 10-90% of the maximum capacity of the load cell. The instrument is calibrated according to the manufacturer's specification.
Pitch Length
A disposable product is held in a flat horizontal configuration by tapes or other suitable means. Two cuts are made along the entire length of the product 12.5 mm on either side of the longitudinal centerline. Each straight cut is made vertically through the entire product along its length from the front edge to the rear edge. The central 25 mm wide strip is removed and the topsheet is cut along the transverse centerline. The length of the specimen along the longitudinal centerline is determined to within ±1 mm under minimal tension. This is the measured pitch length of the product. The adjusted pitch length is the measured pitch length minus the combined length of any material held above or below the upper and lower grip lines in the tensile tester, respectively. Thus, if a specimen is mounted in the tensile tester so that 10 mm at each end of the specimen protrudes past the contact line in the clamps, then the adjusted pitch length is the measured pitch length minus 20 mm.
Outer Cuffs:
A disposable product is held in a flat horizontal configuration by tapes or other suitable means. Outer cuff specimens are cut from the product using a sharp blade. The cuts are made parallel to the longitudinal centerline of the product between the inner and outer cuffs so that the specimens contain all of the outer cuff elastics, but none of the inner cuff material. Each straight cut is made vertically through the entire product along its entire length from the front edge to the rear edge, and all material in the specimen in addition to the cuff (including any nonwoven, topsheet, glue, core, backsheet, etc) is retained in the specimen.
Inner Cuffs:
A disposable product is held in a flat horizontal configuration by tapes or other suitable means. Inner cuff specimens are cut from the product using a sharp blade. The entire inner cuffs are cut along the length of the product immediately above the bond joining the cuff to the topsheet, backsheet or other diaper component.
Testing is performed at 23° C.±2° C. and 50%±2% relative humidity.
Test Procedure:
The gauge length is set to enable the specimen to be mounted with minimal slack so that approximately 10 mm at each end of the specimen protrudes past the contact line in the clamp. The load cell must read between 0 and 0.04 N of force after mounting the sample. If the value exceeds 0.04 N, then the gauge length is reduced in 1 mm increments until the force is between 0 and 0.04 N. A 5.0 gram-force pre-load is applied to the specimen using a crosshead speed of 0.5 inches/minute. The adjusted gauge length of the specimen is the distance between the grip lines when the five gram pre-load is reached. The sample is then extended to 95% of the adjusted pitch length at 254 mm/min (1st load cycle), and held at that elongation for 5 seconds. The crosshead is then returned to the adjusted gauge length at 254 mm/min (1st unload cycle) and held for 5 seconds. The sample is again extended to 95% of the adjusted pitch length at 254 mm/min (2nd load cycle), and held at that elongation for 5 seconds. The crosshead is then returned to the adjusted gauge length at 254 mm/min (2nd unload cycle).
Waist Stretch Test (Pants)
A suitable tensile tester such as an MTS Alliance with MTS Testworks version 4.0 or equivalent is used. The tester is equipped with hook-shaped fixtures 900A, 900B according to the dimensions specified in
Test Procedure:
Step 1:
A sample product is removed from its package and carefully opened to avoid stretching any portion of the product. The crosshead of the tensile tester is raised to a point where the product can be mounted on the upper fixture arm by inserting the free end of the arm through the waist opening of the product, and then through a first leg opening, so that the product hangs freely from the upper arm. The product is positioned on the arm so that the side-panel is centered with respect to the vertical axis of the load cell.
The load cell of the instrument is tared with the product hanging freely from the upper arm. The crosshead is then lowered to a point where the lower fixture arm can be inserted through the waist opening of the product and then through the second leg opening without stretching any portion of the product. The product is positioned so that both side panels are centered with respect to the vertical axis of the load cell, and there is no tension in the waist of the product (i.e. there is slack in the waist). The crosshead is then moved up at a speed of 254 mm/min until a load of 2000 gf is obtained (1st cycle load), and the position of the crosshead is recorded. The crosshead is stopped and held for 30 seconds, then returned to its original position at a speed of 254 mm/min (1st cycle unload).
Waist Stress-Relaxation Test (Taped Diapers)
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 grips that are at least as wide as the width of specimens to be tested, lined with one rubber-coated face and one contact line face for both upper and lower grips. A load cell is used so that the maximum load measured is within 10-90% of the maximum capacity of the load cell. The instrument is calibrated according to the manufacturer's specification.
Testing is performed at 23° C.±2° C. and 50%±2% relative humidity.
Test Procedure:
Step 1:
A sample product is removed from its package and carefully opened to avoid stretching any of the waist or side-panel materials. The gauge length of the tensile tester is set to 30 mm less than the width of the product at a line bisecting the tape tabs when the product is laid flat without stretching any of the waist or side-panel materials. This is the base gauge length. The tape tabs are opened and each tape is mounted in a separate grip on the tensile tester with the grip line immediately adjacent the bond attaching the tape to the rest of the product.
A 5.0 gram-force pre-load is applied to the sample using a crosshead speed of 0.5 inches/minute. When the five gram pre-load is reached this is the adjusted gauge length.
The sample is then immediately extended at a crosshead speed of 508 mm/min [20 in/min] (load cycle) until a force of 15 N is observed. The crosshead is then stopped and returned to the base gauge length at a speed of 508 mm/min (unload cycle), and the sample is removed from the grips. The elongation values at 4 N and 10 N during the load cycle, based on the adjusted gauge length, are recorded.
ΔL4N=(gauge length at 4 N during load cycle)−(adjusted gauge length)
ΔL10N=(gauge length at 10 N during load cycle)−(adjusted gauge length)
Step 2:
A second identical product is removed from its package and carefully opened to avoid stretching any of the waist or side-panel materials. The tape tabs are opened and each tape is mounted in a separate grip on the tensile tester at the base gauge length as described in Step 1 above. The sample is then extended at a crosshead speed of 508 mm/min (load cycle) until the same % elongation is achieved as in Step 1, based on the adjusted gauge length in Step 1. The crosshead is then stopped and held in this position for 60 minutes. The maximum force observed during the Step 2 load cycle (Fmax), and the force at 60 minutes after reaching the maximum % elongation in Step 2 (F60) are recorded.
The dimensions and values disclosed herein are not to be understood as being strictly limited to the exact numerical 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.”
Every document cited herein, including any cross referenced or related patent or application, is hereby incorporated herein by reference in its entirety unless expressly excluded or otherwise limited. The citation of any document is not an admission that it is prior art with respect to any invention disclosed or claimed herein or that it alone, or in any combination with any other reference or references, teaches, suggests or discloses any such invention. Further, to the extent that any meaning or definition of a term in this document conflicts with any meaning or definition of the same term in a document incorporated by reference, the meaning or definition assigned to that term in this 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.
