This invention provides a package for sanitary absorbent articles and a method of packaging the absorbent articles. The present invention also relates to absorbent articles that are individually packed in a rolled configuration, thereby occupying little space. The rolled absorbent articles are further contained in an outer wrap, which helps maintain the rolled shape and protect the absorbent article from contamination. Also disclosed in this invention is the process of rolling the absorbent product, wrapping the rolled absorbent product to form a final product, and placing the final product in secondary packaging for shipping.
Disposable absorbent articles, such as, pantiliners, sanitary napkins, interlabial devices, adult incontinence devices, bandages, breast pads, and diapers are well known in the art. These articles typically have a fluid permeable body-facing side and fluid impermeable garment facing side and may include an absorbent core for retaining fluids therebetween. Such absorbent structures have traditionally been made from readily available and relatively inexpensive materials, such as, cotton fibers, wood pulp fluff, cellulosic tissue, or wadding, or other absorbent materials. These materials have provided satisfactory absorbency of fluids both in terms of absorbency rate and overall absorbent capacity.
Conventionally, absorbent articles, especially sanitary napkins and pantiliners, are commercially available in two different package types.
In one type, a plurality of sanitary articles are positioned within a container such that they are stacked, usually side-by-side. In this type of package, the consumer opens the container, takes out a sanitary article and uses it. The drawbacks to this package type are twofold: the sanitary article has no other protection against contamination, for example, if the user places the article in a handbag for use later, and secondly, the container is now open and the remaining articles may be contaminated over time.
Another type of commercial package available on the market is the individual fold and wrap (IFW). In this package type, each sanitary article is enclosed within a plastic-type package. While this package type may have the convenience of being safe and discreet for use in a handbag, often the type of folding and wrapping suffers from problems. For example, the individual IFW package typically has one side that is open or incompletely sealed, which would allow contaminates such as dust and dirt to enter the interior of the package. Additionally, the sanitary article, in order to be packed, is folded once or twice, creating at least one transverse fold or a flow channel.
Examples of packaging for sanitary napkins can be found U.S. Pat. Nos. 4,505,704 (“'704”); 6,254,582 (“'582”); 4,598,528 (“'528”); and 4,564,108 (“'108”). '704 discloses a continuous strip of napkin material configured in a single roll and mounted in a dispenser. The dispenser has a cutting edge to allow for a transverse tear to separate a segment of desired length by the user. '582 discloses a supply of absorbent panty liners formed by a contiguous longitudinal array of pad segments forming a strip. Each pad segment is shorter than a standard panty liner pad so that by tearing off two, three, four or five segments in one piece, the user can create a panty liner having a length to suit her needs. '528 discloses a series of diapers connected by easily severable areas. These diapers are rolled and may be contained in a dispensing container that allows them to be withdrawn a single diaper at a time. '108 discloses a plurality of napkins having their adhering side releasably fixed to a plastic film. The film may be folded such that the napkins are placed on top of each other forming one or more piles enclosed by the film.
Other types of packaging are known in the art. For example, U.S. Pat. No. 5,964,741 (“'741”) discloses a combination of a vaginal insert and an external absorbent article and includes a pouch. As the external absorbent article is laterally or longitudinally rolled about the vaginal insert, the diameter of the rolled absorbent article must be greater than the vaginal insert. The resulting package may not be discreet enough to be carried in a small purse or pants pocket.
While all of the described patents describe ways to package sanitary articles, none disclose a form that can be easily and discreetly carried in a user's purse or pocket. What is needed therefore is a package that protects the sanitary article from contamination and contains the sanitary article discreetly. Additionally, a method of making such a sanitary article and package is also needed.
Unless specifically defined herein, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although methods and materials similar or equivalent to those described herein can be used in the practice or manufacturing of the present invention, suitable methods and materials are described below. Any publications, patent applications, patents and other documents mentioned herein are incorporated by reference in their entirety. In case of conflict between any document mentioned herein and the instant specification, including definitions, the instant specification will control. In addition, the materials, methods, and examples provided herein are illustrative only and are not intended to be limiting.
Other features and advantages of the invention, e.g., individually rolled disposable absorbent article, will be apparent from the following description and from the claims.
According to a first aspect, the invention provides an individually rolled disposable absorbent article that has a silhouette comprising two opposed end portions, a body facing surface, a garment facing surface and an adhesive. The adhesive is arranged on either one of the body facing surface or garment facing surface for securing the article in a position such as to allow to article to absorb body exudate. The disposable absorbent article is folded to form a folded structure which is wound into a rolled configuration.
According to a second aspect, the invention provides an individually rolled disposable absorbent article that has a silhouette comprising two opposed end portions, a body facing surface, a garment facing surface and an adhesive. The adhesive is arranged on either one of the body facing surface or garment facing surface for securing the article in a position such as to allow to article to absorb body exudate. The disposable absorbent article is wound to form a roll having a peripheral portion, and the first and second end portions are exposed at the peripheral portion.
According to a third aspect the invention provides an individually rolled disposable absorbent article that has a silhouette comprising two opposed end portions, a body facing surface, a garment facing surface and an adhesive. The adhesive is arranged on either one of the body facing surface or garment facing surface for securing the article in a position such as to allow to article to absorb body exudate. The disposable absorbent article is wound to form a roll having a core, wherein the portion of the disposable absorbent article at the core is bent to form an S-shape.
According to a fourth aspect, the invention provides a method for applying a disposable absorbent article to the body of a user, wherein the disposable absorbent article is wound to form a roll having a peripheral portion and first and second end portions of the disposable absorbent article are exposed at the peripheral portion. The method includes pulling on the first and second end portions to unroll the disposable absorbent article and placing the disposable absorbent article in a position with relation to the body of the user such that it can absorb body exudate.
According to a fifth aspect, the invention provides a method for applying a disposable absorbent article to the body, wherein the disposable absorbent article is folded along a fold line to form a folded structure and the folded structure is rolled. The method includes unrolling the disposable absorbent article to at least a partially unrolled configuration, in the at least partially unrolled configuration the disposable absorbent article maintaining a memory of the fold line. The method further includes placing the disposable absorbent article in a position such that it can absorb body exudate by holding it by a portion thereof adjacent the fold line.
According to a sixth aspect, the invention provides a method for making an individually rolled disposable absorbent article. The method includes providing an disposable absorbent article in a substantially unrolled condition, folding the disposable absorbent article to form a folded structure and winding the folded structure into a rolled configuration.
Although various embodiments have been illustrated, this was for the purpose of describing, but not limiting, the invention. Various modifications will become apparent to those skilled in the art and are within the scope of this invention, which is defined more particularly by the attached claims.
A detailed description of examples of implementation of the present invention is provided hereinbelow with reference to the following drawings, in which:
a is a perspective view of the disposable absorbent article of
b is a perspective view of the disposable absorbent article in
c is a perspective view of the disposable absorbent article in
d is a perspective view of the disposable absorbent article in
e is perspective view of the disposable absorbent article in
a is an exploded perspective view of the rolled disposable absorbent article in
b is a detailed perspective view of a portion of the article shown in
In the drawings, embodiments of the invention are illustrated by way of example. It is to be expressly understood that the description and drawings are only for purposes of illustration and as an aid to understanding, and are not intended to be a definition of the limits of the invention.
As used herein, absorbent articles, shall mean disposable absorbent articles such as, pantiliners, sanitary napkins, interlabial devices, adult incontinent devices, breast pads, shoe insoles, bandages, and diapers. These articles are well known in the art. These articles typically have a fluid permeable body-facing side and fluid impermeable garment facing side. Additionally, such articles may include an absorbent core for retaining fluids therebetween.
As seen in
In one embodiment of this invention, the absorbent article 10 is folded transversally to create the fold line 49, as shown in
In still another embodiment of the rolled disposable absorbent article 30 (not shown), the fold line 49 is formed longitudinally and extends between the first longitudinal side 32 and the second longitudinal side 34. As in the previous paragraph, the exterior surface 48 may be formed by the backsheet 40 or the cover 20.
Other rolling directions such as diagonally may also be used, once the disposable absorbent article 10 is folded to form the rolled disposable absorbent article 30.
In the embodiments shown in
For clarity, embodiments of
Once the folded absorbent article 10 has been rolled into a rolled disposable absorbent article 30, it may be covered with an over-wrap 60 to form absorbent device 70 (shown in
Additionally, rolled absorbent articles 30 may be packaged in a small purse-type container, typically made from plastic and which holds a few of the compact articles 30.
The embodiments shown in FIGS. 5 to 10 can also apply to the variant shown in
In a specific and non-limiting example of implementation, the absorbent article of the present invention retains at least some memory after being folded. That is, after being allowed to unroll, the fold line 49 will not entirely vanish. In such case, the portion of the disposable absorbent article 10 defined between the fold line 49 and the transverse end portion 24 will curve away from the remainder of the disposable absorbent article 10. This is best shown in
Area 52 retains some degree of curving due to the memory of the disposable absorbent article 10. The fold line 49 and the adjacent portion 53 smoothes out the main curve. Past the fold line 49 the disposable absorbent article 10 bends downwardly instead of curving up. Consequently, the overall structure is flatter than it would be if the fold line 49 was not present and the main curve was allowed to continue uninterrupted up to the transverse end portion 24. As a result, the disposable absorbent article 10 easier to put in place prior to use. Additionally, the smaller area 53 creates a convenient tab 55 for handling the disposable absorbent article 10. For instance, the user may chose to put the disposable absorbent article 10 in place prior to use by holding it by the tab 55.
In particular, in the embodiments of this invention illustrated in
It has been found that some absorbent articles such as those disclosed in U.S. Ser. No. 10/025299, Drapeable Absorbent Article, hereby incorporated in entirety, are particularly well suited for rolling into the configuration as shown in
The variants of the disposable absorbent article 10 described earlier may include adhesive thereby allowing the disposable absorbent article 10 to be secured in place. The adhesive may be applied on a body facing surface of the disposable absorbent article 10 for attachment to the body of the user, or on the garment facing surface of the disposable absorbent article 10 for attachment to the undergarment of the user. Non-limiting examples of construction of the disposable absorbent article 10 will be described below.
A first body attachable embodiment of the rolled disposable absorbent article according to the present invention is shown in
As depicted in
In the embodiment of the invention shown in
The adhesive 33 used in the article according to the present invention is preferably an adhesive based upon block copolymers, preferably, those which may include linear or radial co-polymer structures having the formula (A-B)x wherein block A is a polyvinylarene block, block B is a poly(monoalkenyl) block, x denotes the number of polymeric arms, and wherein x is an integer greater than or equal to one. Suitable block A polyvinylarenes include, but are not limited to Polystyrene, Polyalpha-methylstyrene, Polyvinyltoluene, and combinations thereof. Suitable Block B poly(monoalkenyl) blocks include, but are not limited to conjugated diene elastomers such as for example polybutadiene or polyisoprene or most preferably hydrogenated elastomers such as ethylene-butylene or ethylene-propylene or polyisobutylene, or combinations thereof, specifically, adhesives consisting of styrene-ethylene-butylenestyrene (SEBS) block copolymer and mineral oils, paraffinic or napthenic process oils, and optionally a suitable tackifying resins include natural and modified resins; glycerol and pentaerythritol esters of natural and modified resins; polyterpene resins; copolymers and terpolymers of natural terpenes; phenolic modified terpene resins and the hydrogenated derivatives thereof; aliphatic petroleum resins and the hydrogenated derivatives thereof; aromatic petroleum resin and the hydrogenated derivatives thereof; and aliphatic/aromatic petroleum resins and the hydrogenated derivatives thereof, and combinations thereof
Specifically, the adhesive 33 may be of the type described in U.S. Pat. No. 6,191,189 to Cinelli et al. In particular, the adhesive may comprise:
The adhesive may also be of the type described in U.S. Pat. No. 6,213,993 to Zacharias et al. In particular the adhesive may comprise a rubber-based adhesive such as styrenebutadiene, polyisobutylene, polybutadiene and polyisoprene; a water soluble adhesive such as polyvinyl alcohol, polyvinyl acetate, and methyl cellulose; a hot melt adhesive such as block copolymers of styrene-butadiene-styrene, styrene-isoprene-styrene, styrene-ethylenepropylene-styrene, styrene-ethylenebutylene-styrene and tetrablock copolymers such as styrene-ethylenepropylene-styrene-ethylenepropylene. Incorporated with the adhesives can be suitable tackifying resins and, if appropriate, oils.
Other adhesive types here include anhydrous gels consisting of 2-hydroxyethyl methacrylate polymer, polyethylene glycol and optionally water as taught in U.S. Pat. No. 4,303,066 and polyurethane gels, as disclosed in U.S. Pat. No. 4,661,099, or silicone gels including commercial products such as Silgel 612 from Wacker Silicones (Adrian, Mich.) or SSA-9700 Soft Skin Adhesives Dow-Corning (Midland, Mich.).
The adhesive 33 may optionally be covered prior to use by a removable release member 47. The release member 47 may comprise a single layer structure or may comprise a laminate structure. For example, the release member may consist of a POLY SLIK® brand paper, available from Loparex Inc., Willowbrook, Ill. As best seen in
As shown in
In a first rolled configuration shown in
The method of applying the disposable absorbent article 400 shown in
Thereafter, the user arranges the disposable absorbent article 400 against the body such that the body facing surface 22 of the cover 20 is in a face to face abutment with the body surface. This can be conveniently accomplished by holding the disposable absorbent article 400 by the tab 55 (
In a second rolled configuration shown in
The user may apply the disposable absorbent article 400 from the rolled to the configuration shown in
Then the user removes the release member 47 from the article 400. Thereafter, the user arranges the disposable absorbent article 400 against the body such that the body facing surface 22 of the cover 20 is in a face to face abutment with the body surface. This can be conveniently accomplished by holding the disposable absorbent article 400 by the tab 55 (
In a third rolled configuration shown in
In the rolled configuration shown in
In a fourth rolled configuration shown in
The different configurations of the rolled absorbent article 400 shown in
Each of the rolled configurations of the disposable absorbent article 400 described above with reference to
A second body attachable embodiment of the rolled disposable absorbent article according to the present invention is shown in
In the disposable absorbent article 500, the backsheet 40 is dimensioned so a portion 61 thereof extends outward relative to a terminal edge 63 of the cover 20. The adhesive 33 for attaching the disposable absorbent article 500 to the body is applied to a body facing surface 65 of the backsheet portion 61. The disposable absorbent article 500 is provided with a removable release member 47 to cover the adhesive 33 prior to use. As shown in
The body attachable rolled disposable absorbent article 500 shown in
In a possible variant, the adhesive and associated release member 47 may be mounted on the backsheet portion 61, rather than the cover 20, for allowing securing the disposable absorbent article 500 to the undergarment of the user.
It is noted that after the articles 400/500 have been used by the user, i.e. after the articles 400/500 have been soiled, the article may be removed by the user and rolled so that the garment facing surface 42 of the backsheet 50 forms the external surface 48 of the rolled article 400/500. In this manner, the user may roll the article 400 or 500 prior to disposal of the article. The adhesive 33 may be selected so that it functions to maintain the soiled article in the rolled state. Alternatively, an adhesive tab or the like may be provided on a terminal end of the article to maintain the soiled article in the rolled configuration.
Cover
The disposable absorbent article of the present invention includes a cover layer 20 overlaying the absorbent material. The exterior of the cover forms the body-facing surface 22 of the disposable absorbent article. As known by those skilled in the art, the cover layer 20 may be formed from any fluid pervious material that is generally compliant, soft feeling, and non-irritating to the user's skin and permits fluid to penetrate to the absorbent core, which retains the fluid. The cover layer 20 generally functions to transport fluid away from the wearer into the absorbent article. In this manner, fluid and moisture are removed from contacting the wearer, thus making the wearer feel dry and comfortable. In addition to transporting fluid, the cover layer 20 may also absorb and/or retain fluid as well.
The cover 20 can be made from any of the materials conventional for this type of use. Non-limiting examples of suitable materials that can be used as the cover layer 20 are woven and nonwoven fabrics formed from fibers or filaments of cellulose, polyester, polypropylene, nylon, rayon fibers and mixtures thereof or the cover layer may be an apertured thermo-plastic film and formed films. Other materials used in making covers layer 20 include gauze or any known porous material with a suitable body contacting surface, including, but not limited to nonwoven webs, plastic nets, and the like. The cover layer 20 could also be made from a fibrous nonwoven composite of bicomponent fibers and pulp fluff.
Apertured films are typically made from a starting film that is a thin, continuous, uninterrupted film of thermoplastic polymeric material. This film may be vapor permeable or vapor impermeable; it may be embossed or unembossed; it may be corona-discharge treated on one or both of its major surfaces or it may be free of such corona-discharge treatment; it may be treated with a surface active agent after the film is formed by coating, spraying, or printing the surface active agent onto the film, or the surface active agent may be incorporated as a blend into the thermoplastic polymeric material before the film is formed. The film may comprise any thermoplastic polymeric material including, but not limited to, polyolefins, such as, high density polyethylene, linear low density polyethylene, low density polyethylene, polypropylene; copolymers of olefins and vinyl monomers, such as, copolymers of ethylene and vinyl acetate or vinyl chloride; polyamides; polyesters; polyvinyl alcohol and copolymers of olefins and acrylate monomers, such as, copolymers of ethylene and ethyl acrylate and ethylenemethacrylate. Films having mixtures of two or more of such polymeric materials may also be used. The machine direction (MD) and cross direction (CD) elongation of the starting film to be apertured should be at least 100% as determined according to ASTM Test No. D-882 as performed on an Instron test apparatus with a jaw speed of 50 inches/minute (127 cm/minute). The thickness of the starting film is preferably uniform and may range from about 0.5 to about 5 mils or about 0.0005 inch (0.0013 cm) to about 0.005 inch (0.076 cm). Coextruded films can be used, as can films that have been modified, e.g., by treatment with a surface-active agent. The starting film can be made by any known technique, such as casting, extrusion, or blowing.
Aperturing methods are known in the art. Typically, a starting film is placed onto the surface of a patterned support member. The film is subjected to a high fluid pressure differential while on the support member. The pressure differential of the fluid, which may be liquid or gaseous, causes the film to assume the surface pattern of the patterned support member. Portions of the film overlying apertures in the support member are ruptured by the fluid pressure differential to create an apertured film. A method of forming an apertured fibrous film is described in detail in commonly owned U.S. Pat. No. 5,827,597, which is incorporated herein by reference.
Apertured film can also be made by any other suitable process or method known to those skilled in the art.
Bicomponent fibers are known in the art and are composed of two polymers with different melting points. At least a portion of the outer surface of each bicomponent fiber has the lower melting polymer. The two polymers may be arranged such that a cross-section of the fiber shows the two polymers in a side-by-side array. Alternatively, the polymers may be positioned in a so-called sheath/core arrangement, in which a core of higher melting polymer is surrounded by a sheath of lower melting polymer. A useful bicomponent fiber is a 3.0 denier, 1.5″ long staple fiber made of a polyester core and a high density polyethylene sheath. Similar fibers (polyethylene sheath and polypropylene core) are available as Danaklon ES-C or ES Bico (Danaklon A/S, Varde Denmark). Pulp fibers may be obtained as IP “‘SUPERSOFT” ELM supplied by the International Paper Company (Memphis, Tenn.), “‘RAYFLOC” XJ-HM E-Type Cellulosic Fluff Pulp, (ITT Rayonier), or Korsnas Vigorfluf-EN White (KorsncAs, Gavle, Finland).
The cover layer 20 may optionally be treated with surfactant to manipulate the hydrophobicity/hydrophilicty thereof to facilitate optimal fluid transport properties. The fibers or other materials that make up the cover layer 20 should not collapse or lose their resiliency when subjected to body fluid. The fibers may be oriented by a carding process and thermally bonded via embossing. The fiber or filament can be single denier or multidenier.
The cover may be a single layer or be made from multiple layers. The thickness of the cover may vary from about 0.001 inch (0.025 mm) to about 0.200 inch (5.000 mm), depending on the material chosen. The weight of the body facing layer material preferably is between about 5 and about 150 gsm.
For example, any material with cloth-like features may be used for the body facing layer. Such material includes nonwoven, such as spunlace, woven, and knitted materials. In particular, spunlace material may be made from about 0 to about 100% rayon and from about 0 to about 100% polyester. The spunlace material may also be made from about 10 to about 65% rayon and from about 35 to about 90% polyester may be used. Optionally, the material used for the body-facing layer may include binders, such as thermoplastic binder fibers and latex binders.
In one embodiment, the cover is a single sheet of material having a width sufficient to form the body-facing surface of the absorbent article. In another embodiment, the cover has at least two layers.
The cover, whether a single layer or multiple layers, may also have absorbent capabilities, i.e., retains fluid. If a separate absorbent layer is used, the body facing layer may be longer and wider than the absorbent core or be of similar size as the absorbent core.
Generally, the cover layer 20 is a single sheet of material having a width sufficient to form the body-facing surface 22 of the disposable absorbent article. The cover layer 20 may be longer and wider than the optional absorbent core.
The cover layer 20 may be embossed with shapes within a given area. For example, a series or a number of features, e.g., circles, triangles, squares, lines, honeycomb, diamond, floral, etc. are embossed over the entire length and width of the outer surface of web. Each embossed feature has a major and minor axis extending therethrough, the major axis length being greater or equal to the minor axis length. The embossed features may be in a repetitive pattern.
Transfer Layer
Optionally, the disposable absorbent article of the present invention may include a transfer or distribution layer. The transfer layer or distribution layer, if present, is generally positioned beneath the cover 20 and the transfer layer usually directly contacts the absorbent core. If included, the transfer layer may be made of any known material that will take up fluid and then distribute and release it to an adjacent absorbent layer for storage. Transfer layers have a relatively open structure that allows for movement of fluid within the layer. Suitable materials for such transfer layers include fibrous webs, resilient foams, and the like.
The transfer layer provides a means of receiving body fluid from the fluid-pervious cover layer 20 and holding it until the absorbent core has an opportunity to absorb it. The transfer layer is, preferably, more dense than the cover layer 20 and has a larger proportion of smaller pores than does the cover layer 20. These attributes allow the transfer layer to contain body fluid and hold it away from the outer side of the cover layer 20, thereby preventing the fluid from re-wetting the cover layer 20 and its outer surface. However, the transfer layer is preferably not so dense as to prevent the passage of the fluid through the transfer layer and into the underlying absorbent core.
In one non-limiting example of implementation a cover/transfer layer laminate may be used. Such composite layer may include an embossed pattern on the outer surface. For example, flowers and rails depicted in U.S. Des. Pat. No. 439,057 are embossed after the composite is formed, which results in an embossed pattern having flowers, rails, and squares.
In one embodiment of the present invention, the cover and transfer layers are joined to form a laminate. This two layer structure is particularly useful in personal care products such as feminine sanitary protection products having body-contacting, facing or cover layers, such as, transfer or fluid handling layers, or as other components of personal care products. The laminates of the invention have been found to exhibit improved fluid-handling properties when used in disposable absorbent articles, such as, for instance, feminine sanitary protection products.
Absorbent Structure
The absorbent core 50 of the present invention may contain any known absorbent materials including, but not limited to, absorbent fibers, such as, cellulose fibers, including, but not limited to wood pulp, regenerated cellulose fibers, e.g., rayon and cotton fibers, rayon fibers and the like; superabsorbent powders (SAP) like Sumitomo SA-70 or fibers (SAF), other naturally occurring absorbent materials, such as, sphagnum or peat moss; and other synthetic absorbent materials, such as, foams and the like. The absorbent core 50 may also be made from multiple components and contain a structure such as that disclosed in U.S. Ser. No. 10/652,171, entitled DISPOSABLE ABSORBENT ARTICLES, filed Aug. 29, 2003, which is herein incorporated by reference in its entirety. Additionally, the absorbent core 50 may include one or more of the following: binders, such as, thermoplastic and latex, odor-controlling compounds, e.g., perfumes, EDTA (ethylenediaminetetraacetic acid), anti-microbial agents, wetting agents, wetness indicator material, materials for administering or delivering medicaments, such as encapsulated medicaments, and materials for maintaining skin moisture, such as encapsulated moisturizers.
For example, the absorbent core 50 may be made from material such as a fluffy batt cut from a relatively loose web of non-woven fibers having a relatively high absorptive capacity. While the absorbent core can have any shape or silhouette, it usually has an asymmetric configuration. The absorbent core 50 may also be made from material such as a fibrous batt having an integral densified layer. In such a case, if a backsheet is desired, the absorbent core is positioned on the backsheet of the absorbent article so that the densified layer adjoins the backsheet. The densified layer has relatively higher wettability and liquid retentivity than the rest of the aforesaid batt and usually is formed by slightly moistening one surface of the batt and thereafter compressing the moistened surface. The absorbent core 50 may also be formed from multiple layers, each having a different density such that the uppermost layer (closest to the body) is less dense than the outer (closest to the garment).
Additionally, the absorbent core 50 may be formed of absorbent material made from an offline-formed, homogeneously mixed, air-laid layer, roll good laminate or any other offline-formed absorbent composite.
The absorbent core may include only materials, such as, a hot melt adhesive containing fluid absorbing polymers. One example of such a material is disclosed in EP 1 013 291 A1, the disclosure of which is herein incorporated in entirety by reference.
Additionally, additives may be incorporated into the absorbent core, such as, surfactants, SAP, and SAF. These additives may provide additional benefits such as enhanced fluid penetration and increased fluid absorption. For example, in one embodiment, the absorbent layer is made of absorbent material that is made from a layer of pulp. In another embodiment, SAP is mixed with the pulp to form an absorbent composite. This composite may be condensed to form a dense, thin layer. One example of such a material is Novathin® available from Rayonier, Jesup, Ga.
SAP are particles that are capable of absorbing many times, at least 10, more preferably 15, and still more preferably over 15, their weight in exudate, under a pressure of 0.5 psi. It should be noted that, in the context of the present invention, there is no restriction that the superabsorbent particles actually be particulate. This expression is intended to cover superabsorbent fibers, and other superabsorbent materials, whatever their form and shape. These superabsorbent particles generally fall into three classes, namely starch graft copolymers, cross-linked carboxymethylcellulose derivates and modified hydrophilic polyacrylates. Examples of such absorbent polymers are hydrolyzed starch-acrylonitrile copolymer graft copolymer, a neutralized starch-acrylic acid graft copolymer, a saponified acrylic acid ester-vinyl acetate copolymer, a hydrolyzed acrylonitrile copolymer or acrylamide copolymer, a modified cross-linked polyvinyl alcohol, a neutralized self-cross-linking polyacrylic acid, a cross-linked polyacrylate salt, carboxylated cellulose, and a neutralized cross-linked isobutylene-malasic anhydride copolymer. In one embodiment of the invention, the superabsorbent particle is a cross-linked polyacrylate salt.
Barrier Layer
The barrier layer, also called backsheet 40, may be located adjacent to the cover as shown in
Optionally, the backsheet 40 may be breathable, i.e., permits vapor to transpire. Known materials for this purpose include nonwoven materials, monolithic and microporous films in which microporosity is created by, inter alia, stretching an oriented film. Single or multiple layers of permeable films, fabrics, melt-blown materials, and combinations thereof that provide a tortuous path, and/or whose surface characteristics provide a liquid surface repellent to the penetration of liquids may also be used to provide a breathable backsheet.
Bonding Methods
The layers of the absorbent article may be, but not necessarily, bonded, e.g., glued or adhered, to the adjacent layer. For example, the underside of the cover 20 may be adhered to the topside of the absorbent core 50. The underside of the absorbent core 50 may be adhered to the topside of the barrier layer 40. Any methods known in the art, such as, fusion bonding, adhesive attachment, or by any other securement means can be used to secure the individual layers together to form the final absorbent article. Included within such methods are co embossing, thermobonding, mechanical bonding, and the like. Fusion bonding includes heat bonding, ultrasonic bonding, and the like.
Adhesive is typically used to attach the layers into a single absorbent article. For example, in one embodiment, the body facing cover 20 is attached to the barrier layer 40 with adhesive HL 1491 available from H.B Fuller and Company (St. Paul, Minn.). The adhesive may be applied in any method.
Adhesive may include pressure sensitive adhesive that is applied as strips, swirls, or waves, and the like. As used herein, the term pressure-sensitive adhesive refers to any releasable adhesive or releasable tenacious means. Suitable adhesive compositions include, for example, water-based pressure-sensitive adhesives such as acrylate adhesives. Alternatively, the adhesive composition may include adhesives based on the following: emulsion or solvent-borne adhesives of natural or synthetic polyisoprene, styrene-butadiene, or polyacrylate, vinyl acetate copolymer or combinations thereof, hot melt adhesives based on suitable block copolymers—suitable block copolymers for use in the invention include linear or radial co-polymer structures having the formula (A-B)x wherein block A is a polyvinylarene block, block B is a poly(monoalkenyl) block, x denotes the number of polymeric arms, and wherein x is an integer greater than or equal to one. Suitable block A polyvinylarenes include, but are not limited to Polystyrene, Polyalpha-methylstyrene, Polyvinyltoluene, and combinations thereof. Suitable Block B poly(monoalkenyl) blocks include, but are not limited to conjugated diene elastomers such as for example polybutadiene or polyisoprene or hydrogenated elastomers such as ethylene butylene or ethylene propylene or polyisobutylene, or combinations thereof. Commercial examples of these types of block copolymers include Kraton™ elastomers from Shell Chemical Company, Vector™ elastomers from Dexco, Solprene™ from Enichem Elastomers and Stereon™ from Firestone Tire & Rubber Co.; hot melt adhesive based on olefin polymers and copolymers where in the olefin polymer is a terpolymer of ethylene and a comonomers, such as vinyl acetate, acrylic acid, methacrylic acid, ethyl acrylate, methyl acrylate, n-butyl acrylate vinyl silane or maleic anhydride. Commercial examples of these types of polymers include Ateva (polymers from AT plastics), Nucrel (polymers from DuPont) and Escor (from Exxon Chemical).
In one embodiment, the cover and core are co-embossed into an absorbent structure. Depressions formed from the co-embossing allow the absorbent article to be rolled into a compact structure without the cover surface wrinkling.
The absorbent article of the present invention may be applied to the crotch of a garment by placing the garment-facing surface against the inside surface of the crotch of the garment. Various methods of attaching absorbent articles may be used. For example, chemical means, e.g., adhesive, and mechanical attachment means, e.g., clips, laces, ties, and interlocking devices, e.g., snaps, buttons, VELCRO (Velcro USA, Inc., Manchester, N.H.), zipper, and the like are examples of the various options available to the artisan.
Adhesive may be applied to the garment-facing side of the absorbent article. The positioning adhesive may be any adhesive known in the art. As a non-limiting example, pressure sensitive adhesive strips, swirls, or waves may be applied to help maintain the absorbent article in place. As used herein, the term pressure-sensitive adhesive refers to any releasable adhesive or releasable tenacious means. Suitable adhesive compositions include, for example, water-based pressure-sensitive adhesives, such as acrylate adhesives. Alternatively, the adhesive composition may include rapid setting thermoplastic “hot melt,” rubber adhesives, two-sided adhesive tape, and the like.
Where positioning adhesive is used on the garment-facing side of the barrier layer 40, a release strip may be applied to protect the adhesive on the absorbent article prior to attaching the absorbent article to the crotch. The release strip can be formed from any suitable sheet-like material that adheres with sufficient tenacity to the adhesive to remain in place prior to use but which can be readily removed when the absorbent article is to be used. Optionally, a coating may be applied to release strip to improve the ease of removabilty of the release strip from the adhesive. Any coating capable of achieving this result may be used, e.g., silicone. Because typical release strips have memory properties, it is contemplated that while a release strip can be used with the rolled disposable article of the present invention, the memory properties of the disposable absorbent article of the present invention are separate and distinct from any memory properties of the release paper.
Wings
Wings, also called, among other things, flaps or tabs, may also be part of the absorbent article of the present invention. Wings and their use in sanitary protection articles are described in U.S. Pat. No. 4,687,478 to Van Tilburg; U.S. Pat. No. 4,589,876 also to Van Tilburg, U.S. Pat. No. 4,900,320 to McCoy, and U.S. Pat. No. 4,608,047 to Mattingly. The disclosures of these patents are incorporated herein by reference in their entirety.
As disclosed in the above documents, wings are, generally speaking, flexible and configured to be folded over the edges of the underwear so that the wings are disposed between the edges of the underwear.
In addition, there may be one or a plurality of wings incorporated into the present invention. Where opposed wings are present along the longitudinal edges of the absorbent article of the present invention, such wings may be directly opposed or may be offset from the wings located along the opposite longitudinal edge of the absorbent article.
When present, the wings may be folded inwardly or outwardly prior to rolling the disposable absorbent article.
Overwrap
The rolled absorbent article can be maintained in a rolled configuration using a wrapper, a ring, a hook and loop system, adhesives and mixtures thereof. For example, a wrapper made of standard cellophane or polypropylene films and including any heat sealable material may be used.
The overwrap can also be embossed (including microembossing), electronically altered (including corona discharge treatments), coated (including vapor deposition, and sputtering) and the like.
In addition, slip agents such as fluid lubricants or solid layers with a reduced coefficient of friction may be applied to the overwrap package at any appropriate portion of the manufacturing process.
Additionally, the wrapper may have a tear strip located near the middle of the product, and one or more portions of the package are then slid off the ends.
Miscellaneous
Any or all of the cover, absorbent layer, transfer layer, backsheet layer, and adhesive layers may be colored and/or transparent. Such coloring includes, but is not limited to, white, black, red, yellow, blue, orange, green, violet, and mixtures thereof. Color may be imparted according the present invention through dying, pigmentation, and printing. Colorants used according the present invention include dyes and inorganic and organic pigments. The dyes include, but are not limited to, anthraquinone dyes (Solvent Red 111, Disperse Violet 1, Solvent Blue 56, and Solvent Green 3), Xanthene dyes (Solvent Green 4, Acid Red 52, Basic Red 1, and Solvent Orange 63), azine dyes (Jet black), and the like.
Inorganic pigments include, but are not limited to, titanium dioxide (white), carbon black (black), iron oxides (red, yellow, and brown), chromium oxide (green), ferric ammonium ferrocyanide (blue), and the like.
Organic pigments include, but are not limited to diarylide yellow AAOA (Pigment Yellow 12), diarylide yellow AAOT (Pigment Yellow 14), phthalocyanine blue (Pigment Blue 15), lithol red (Pigment Red 49:1), Red Lake C (Pigment Red), and the like.
Also contemplated herein are asymmetrical and symmetrical articles having parallel longitudinal edges, dog bone- or peanut-shaped, circular, oval and the like. The silhouette of the disposable absorbent article of the present invention may be configured to be used with conventional underwear or may be configured to conform to thong garments. As used herein, the term thong includes, but is not limited to, thong underwear, thong swimming suit bottom, G-strings, Rio cut underwear, Rio cut swimming suit bottom, Brazilian cut underwear, Brazilian cut swimming suit bottom, and any other garment that exposes the buttocks, having a narrow strip of fabric or a cord that passes between the thighs supported by a waistband, a waist cord, belt or the garment itself. The absorbent article may include other known materials, layers, and additives, such as, foam, net-like material, perfumes, medicaments or pharmaceutical agents, moisturizers, odor control agents, and the like. The absorbent article can optionally be embossed with decorative designs.
The absorbent article 10 may be made from any of the processes known to one of ordinary skill in the art. For example, a continuous length of cover material may be laminated to a continuous length of absorbent material. This laminate may then be laminated to a backsheet to form an absorbent article. The absorbent article can then be rolled up and over-wrapped to form a single unitary or individual absorbent article. In another embodiment, the cover is laminated to the backsheet and then rolled up and over-wrapped.
A flowchart of the process for manufacturing an absorbent article according to the invention is shown at
The absorbent articles are then transported on a conveyor belt to a formation station where the individual absorbent articles are rolled (step D). In the embodiment (step E) that produces the disposable absorbent article 30 shown at
In the embodiment shown at
At the wrapping station (step F), cellophane is processed such that a hollow tube with at least one open end is formed. The cellophane tube is slightly larger than the rolled absorbent article. The rolled absorbent article is inserted into the hollow cellophane tube and the end(s) of the cellophane tube are sealed. The cellophane tube may include a tear strip such as those disclosed in U.S. Pat. No 4,170,305 to Hull.
The wrapped absorbent article is then placed into secondary package, e.g., box, pouch, container, and the like (step G).
The entire contents of all patents and patent applications listed or described above are incorporated herein by reference.
From the foregoing description, one skilled in the art can ascertain the essential characteristics of this invention, and without departing from the spirit and scope thereof, can make various changes and modifications. Embodiments set forth by way of illustration are not intended as limitations on the variations possible in practicing the present invention.
Although the invention is illustrated and described above with reference to specific embodiments, the invention is not intended to be limited to the details shown. Rather, various modifications may be made in the details within the scope and range of equivalents of the claims and without departing from the invention. It is expressly intended, for example, that all ranges broadly recited in this document include within their scope all narrower ranges that fall within the broader ranges.
This application claims priority to application Ser. No. 60/725,433 filed on Oct. 11, 2005 the entire contents of which are incorporated by reference herein.
Number | Date | Country | |
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60725433 | Oct 2005 | US |