MXPA96004112A - Laminated material capi - Google Patents

Abstract

The present invention relates to a laminated material characterized by: a first sheet and a second sheet, said first sheet being permeable to fluids, said first sheet and said second sheet being further separated from each other by at least one separator to define a capillary zone between them for the capillary movement of the fluid, said separator connecting said first sheet and said second sheet together to form said laminated material, said separator keeping the first sheet and the second sheet at a sufficient dimensional separation to impart capillary force to a fluid that enters the capillary zone and moves said fluid within said capillary zone through the capillary pressure

Description

CAPILLARY LAMINATED MATERIAL TECHNICAL FIELD The present invention relates to laminated materials, and more particularly the present invention relates to laminated materials having a capillary zone or passage for acquiring, moving and / or storing fluids within the laminated material. The laminate material of the present invention is particularly suitable for use as a sheet. top, an acquisition layer and / or an absorbent core in absorbent articles such as disposable diapers, catamenial pads, sanitary napkins, absorbent bands, incontinence articles and the like.

BACKGROUND OF THE INVENTION It has been widely known in the art of disposable absorbent articles that it is extremely It is desirable to construct absorbency articles such as disposable diapers, catamenial pads, sanitary napkins, absorbent strips, incontinence articles and the like, which present a dry surface feel to the wearer to improve comfort of use and minimize the development of conditions. undesirable to the skin, due to prolonged exposure to moisture absorbed inside the article. A commercially used solution to the aforementioned problem is to use a nonwoven web as a topsheet on a disposable absorbent article. The nonwoven web top sheet provides a smooth surface in contact with users' skin. The moisture deposited on the upper nonwoven web sheet is transmitted through the openings between the fibers and towards the absorbent core. However, due to the random arrangement of the fibers within the non-woven upper sheet, part of the moisture tends to be suspended or collected within the non-woven web creating an undesirable condition, while exposing the skin to moisture inside. the non-woven plot. Another solution to the aforementioned problem is described in the commonly assigned U.S. Patent No. 4,342,314 issued to Radel et al. On August 3, 1982, and is incorporated herein by reference. Radel et al. Describe an absorbent article with a top sheet that makes contact with the user comprising a plastic, three-dimensional, macroscopically expanded, elastic web that exhibits a combination of plastic and fiber-like properties. In a preferred embodiment, the three-dimensional, macroscopically expanded plastic web top sheet, described in Radel et al., Exhibits a fine-scale three-dimensional microstructure comprising a regulated continuous capillary network, progressively decreasing in size, originating in and extending from a surface of the weft and ending in the form of openings in the opposite surface thereof to promote the rapid transport of fluids in the direction of decreasing capillary size. The fiber-like appearance of the weft is comprised of elements similar to continuous fibers, the opposite ends of each of the fiber-like elements being interconnected to at least one of the fiber-like elements. A typical capillary network in the structure of Radel and others, comprises a capillary upper opening or aperture formed by a multiplicity of interconnected fiber-like elements ". each other in the upper plane of the plot. The upper opening may, if desired, be further subdivided into smaller capillary openings by the fiber-like secondary and tertiary elements in planes located below the surface contacting the wearer of the screen. Each of the fiber-like elements exhibits a substantially uniform U-shaped cross-section along its length. In the case of a fiber-like primary member, its cross section comprises a base portion located in the plane that contacts the user and a sidewall portion attached to each edge of the base portion and extending generally in the direction of the contacting surface of the absorbent pad of the weft. The lateral wall portions that intersect each other are joined to one another intermediate the surface that makes contact with the user and the surface that makes contact with the absorbent alhomadilla of the weft, with which forming a capillary network "that interconnects the opposite surfaces of the plot. Secondary and tertiary fiber-like elements, when used, are generally similar, but originated in planes below the surface that makes contact with the wearer of the weft. One drawback associated with the use of top sheets comprised of plastic is that despite their superior fluid handling characteristics, some users are very reluctant to place the top sheet which they quickly perceive as plastic by virtue of their glossy appearance in contact with their skin. To reduce the luster on the visible surface of the weft, that is, that portion of the weft that is visible from above directly, we have learned that the inclusion of a microscopic pattern of surface aberrations that are not discernible when the perpendicular distance between the Observer's eye and a plane of the frame is approximately 12 inches, it is highly effective. The commonly assigned U.S. Patent No. 4,463,045 issued to Ahr et al., July 31, 1984, and hereby incorporated by reference, defines the relevant criteria that must be satisfied in such a manner that the three-dimensionally expanded web will exhibit a visible surface substantially not glossy. The top sheet of the type generally described in Radel et al., Which has surface aberrations according to Ahr et al., Exhibits a fiber-like appearance and impression to the touch, also as a visible non-glossy surface. In addition, it is highly effective in promoting the rapid transfer of fluid from the first or surface contacting the user to the second or surface contacting the absorbent pad of the top sheet. The upper sheets of the latter type have enjoyed wide commercial success in catamenial alhomadillas due to their clean and dry appearance. in use, when contrasted to conventional nonwoven fibrous top sheets. Although non-woven upper sheets and plastic top sheets of the type generally described in Radel et al. And Ahr et al. Have enjoyed wide commercial success, it will be readily appreciated that further improvements in clean and dry appearance in use are still desirable. products of this type.

SUMMARY OF THE INVENTION The present invention relates, in a preferred embodiment, to a capillary laminate comprised of at least two layers or sheets having a capillary zone between the sheets. The capillary zone between the sheets is established and maintained by at least one separating element which simultaneously retains the two separate layers and keeps them apart further. In a preferred embodiment the capillary laminate includes a plurality of spacer elements. At least one of the leaves is permeable to fluids to allow the fluid to enter the capillary zone. Another preferred embodiment of the present invention relates to a capillary laminate formed by at least two fluid-permeable sheets having a capillary zone between the sheets that are held apart by the separating elements. The capillary laminate may be formed of more than two sheets such that multiple capillary zones are formed. The upper or uppermost sheet and all the intermediate sheets are permeable to fluids to allow the flow of fluid between the adjacent capillary zones. The lower or lower sheet may be either peelable or impermeable to fluids depending on the intended use and / or result. The separating elements within the capillary laminate can be formed or arranged to divide the capillary zone into capillary channels that direct fluid flow within the capillary zone. The sheets of the capillary laminate material can exist in many forms and can be made from a number of suitable materials. The sheets may be non-woven wefts, films, microporous sheets, porous sheets, etc. The sheets can be made from a number of suitable materials including but not limited to polyolefins, polyester, nylon, elastomers, etc. The sheets of the capillary laminate can be made permeable to fluids by various mechanisms. These include, but are not limited to, openings, pore media, micropore media, slots, etc. When openings are used to make the sheet, or sheets, permeable to fluids, these can be provided in numerous configurations and patterns to obtain various results. The openings in a sheet may all be of the same size or may vary. For example, the sheet may have large openings near the point of maximum fluid supply and smaller openings away from the point of maximum fluid supply. The frequency of the openings can also be varied across the surface of the sheet, with a much higher frequency in one location than in another. The frequency of opening and / or size can also be varied between the adjacent sheets within the capillary laminate to achieve certain desired flow properties. For example, the successively smaller openings in the adjacent sheets can be used to create a capillary driving force through the capillary laminate in the direction of the smaller openings. The separator elements used to separate and secure the sheets of the capillary laminate together may be a single separator or a plurality of separators "having various geometric shapes. The height of the spacers will determine the clear between the leaves or the capillary zone. The capillary zone can be designed to optimally handle different fluids. For example, it has been determined that for blood or menstruation, the capillary zone should be approximately 0.00762 cm. Water or urine is an improvement transferred by a smaller capillary area. The capillary zone can be varied throughout the length of the capillary laminate. The variability of the capillary zone can be used to promote fluid flow in the direction of the decreasing capillary zone. The separators used to form the capillary laminate can be formed of a material that is added to the sheets or one of the sheets themselves. Examples of materials that may be added include, but are not limited to hot melt adhesives, pressure sensitive adhesives, thermoplastics with a low melting point temperature of one or more sheets, etc. These additional materials can be applied by screen printing, gravure printing or any number of processes that are known to those skilled in the art. Alternatively, the spacers can be formed from one or more of the sheets themselves. This can be achieved by embossing, either hot or cold, molding or other process known to those skilled in the art. The separators can also be used to divide the capillary zones into capillary channels. The capillary channels can be used to direct the flow within the capillary zone. The capillary channels can be linear, curvilinear or a combination of both. The capillary channels may be uniform in cross sectional area or may vary along their length. For example, a decreasing cross-sectional area of a capillary channel can promote fluid flow in the direction of the decreasing cross-sectional area.

"Brief Description of the Dibules Although the description concludes with claims that particularly point out and distinctly claim the present invention, it is believed that the invention will be better understood from the following description, taken in conjunction with the accompanying drawings, where the same reference number is given to similar parts, and where: Figure 1 is a top plan view of a sanitary napkin with portions of the sanitary napkin trimmed to show more clearly the construction of the sanitary napkin; Figure 2 is a cross-sectional view of the sanitary napkin of Figure 1, taken along section line 2-2; Figure 3 is a sectional view of a preferred embodiment of a capillary laminated film of the present invention; and Figure 4 is a cross-sectional view of the capillary laminated film of Figure 3; Figure 5 is a perspective illustration, partially segmented, amplified, of a preferred embodiment of a capillary laminated film of Figure 3, having been formed into a perforated, macroscopically expanded, three-dimensional frame, of the type generally described in the Patent of the United States No. 4,342,314; Figure 6 is a sectional view of another preferred embodiment of a capillary laminated film of the present invention; Figure 7 is a cross-sectional view of the capillary laminated film of Figure 6; and Figure 8 is a cross-sectional view of another preferred embodiment of a capillary laminated film of the present invention.

Detailed Description of the Present Invention As used herein, the term "absorbent article" refers to devices that absorb and continue body exudates, and more specifically refers to devices that are placed against or in proximity of the user's body to absorb and contain the various exudates discharged from the body. The term "absorbent article" is intended to include diapers, catamenial pads, sanitary napkins, panty liners, incontinent pads, and the like. The term "disposable" is used herein to describe "absorbent articles" that are not intended to be washed or otherwise restored or reused as an absorbent article (ie, they are intended to be discarded after a single use, and preferably to be recycled, composted or otherwise disposed of in an environmentally compatible manner). A "unitary" absorbent article refers to absorbent articles that are formed of separate parts joined together to form a co-ordinate entity so as not to require separate manipulated parts such as in a separate holder and pad. A preferred embodiment of a disposable absorbent article of the present invention is the catamenial pad, the sanitary napkin 20 shown in Figure 1. As used herein, the term "sanitary napkin" refers to an absorbent article that is used by women adjacent to the pudendal region, generally external to the urogenital region, and intended to absorb and contain menstrual fluids and other vaginal discharges from the wearer's body (eg, blood, menstruation, and urine). Interlabial devices that reside partially within and partially outside the wearer's vestibule are also within the scope of this invention. As used herein, the term "pudendal" refers to the externally visible female genitalia. It should be understood, however, "that the present invention is also applicable to other catamenial pads or for feminine hygiene such as panty liners, or other absorbent articles such as incontinence pads and the like. The sanitary napkin 20 has two surfaces, a contact surface with the body or "surface of body 20a and a garment surface 20b The sanitary napkin 20 is shown in Figure 1 as viewed from its body surface 20a The body surface 20a is intended to be worn adjacent to the wearer's body. of garments 20b of sanitary napkin 20 (shown in Figure 2) is on the opposite side and is intended to be placed adjacent to the wearer's undergarments when sanitary napkin 20 is used. Sanitary napkin 20 has two central lines, a longitudinal center line "1" and a transverse center line "t". The term "longitudinal", as used herein, refers to a line, an axis or an address in the plane of the sanitary napkin 20 that is generally aligned with (i.e., is approximately parallel to) a vertical plane that bisects a user standing on left and right halves of the body when the sanitary napkin 20 is used. The terms "transverse" or "lateral", as used herein, are interchangeable, and refer to a line, an axis or a direction lying within the plane of the sanitary napkin 20"which is generally perpendicular to the longitudinal direction. Figure 1 is a top plan view of the sanitary napkin 20 of the present invention in its flat state with parts of the sanitary napkin being trimmed to more clearly show the construction of the sanitary napkin 20 and with the part of the sanitary napkin 20 sanitary towel 20 facing or contacting the user 20a oriented towards the observer. As shown in Figure 1, the sanitary napkin 20 preferably comprises a liquid-permeable top sheet 22, a liquid-impermeable back or back sheet 23 bonded to the topsheet 22, and an absorbent core 24 positioned between upper sheet 22 and the back sheet 23, and an acquisition layer 25 placed between the upper sheet 22 and the absorbent core 24. Figure 1 also shows that the sanitary napkin 20 has a periphery 30 which is defined by the outer edges of the sanitary napkin 20, in which the two longitudinal edges (or "side edges") are designated as 31 and the end edges or "ends") are designated 32. The sanitary napkin 20 preferably includes optional side flaps or "wings" "34 that are folded around the crotch portion of the wearer's panties. The side flaps 34 can serve a number of purposes, including, but not limited to, protecting the wearer's panties from staining and keeping the sanitary pad secured to the wearer's panties. Figure 2 is a cross-sectional view of the sanitary napkin 20, taken along the line of section 2-2 of Figure 1. As can be seen in Figure 2, the sanitary napkin 20 preferably includes a means adhesive fastener 36 for attaching the sanitary napkin 20 to a user's undergarments. Removable, removable liners 37 cover the adhesive fastening means 36 to prevent the adhesive from sticking to a surface other than the crotch portion of the underwear prior to use. In addition to having a longitudinal direction and a transverse direction, the sanitary napkin 20 has a "Z" direction, which is the downstream direction through the topsheet 22 and toward any of the fluid storage cores 24. that can be provided. The aim is to provide a continuous path between the topsheet 22 and the underlying layer or layers of the absorbent articles of the present, such that the fluid is eventually directed in the "Z" direction and away from the top sheet of the article and towards its last layer of storage. Referring now to Figures 3 and 4, there is shown a capillary laminate 40 of the present invention. The capillary laminate 40 is particularly well suited for use as a topsheet 22 or acquisition layer 25 in a sanitary napkin 20 of the type / 'generally illustrated in Figures 1 and 2. The capillary laminate material 40 shown in Figures 3 and 4 comprises a first fluid-permeable sheet or layer 42 and a second fluid-permeable sheet or sheet 46. The permeable nature of The fluids of the first sheet 42 and the second sheet 46 are provided by openings 43 and 47, respectively. Although the fluid-permeable nature of the first and second sheets 42 and 46 is provided by the openings 43 and 47, it would be obvious to one of ordinary skill in the art that there are other means of imparting a fluid-permeable nature to a sheet, such as microporous materials, porous material, grooves, etc. The first and second sheets are separated apart by a separator. The separator shown in Figures 3 and 4 comprises a plurality of cylindrical separators 48. The separators 48 also serve to connect or secure the first sheet 42 to the second sheet 46. The separators 48 separate the first sheet 42 from the second sheet 46, such "that a" capillary zone "50 is created between the first sheet 42 and the second sheet 46. As used herein, the term" capillary zone "refers to the space between the two adjacent sheets that is not occupied by a separator. The material selected for the first sheet 42 and the second sheet 46 is preferably mountable and capable of being formed into a sheet. Since the capillary-layered material 40 will be used in consumer products that make contact with the human body, the capillary laminate 40 is preferably soft and secure for the epidermis or other human contact. Preferred materials for the first layer 42 and the second layer 46 are polymeric materials including, but not limited to polyolefins, particularly polyethylenes, polypropylenes and copolymers having at least one olefinic constituent. Other polymeric materials such as nylon, polyester, copolymers thereof and combinations of any of the foregoing may also be suitable. Although the first sheet 42 and the second sheet 46 are shown as a film, the sheets may, if desired, be in the form of a nonwoven web, microporous membrane, foam, etc. If desired, conventional amounts of agents can also be added to the polymer matrix of the first sheet 42 and the second sheet 46. It is often desired to add agents to increase the opacity of the sheets. Bleaching agents, such as titanium dioxide and calcium carbonate, can be used to dull the first and second sheets, 42 and 46, respectively. It may also be desirable to add other agents such as surfactants to impart a hydrophilic nature to either the first sheet 42 or the second sheet 46. Degrees and amounts to which the agents including bleaches and surfactants are added to the first sheet 42 and the second sheet 46 may be different from each other to provide varied effects such as hydrophilicity gradients and the ability to mask fluids within the absorbent article. The first sheet 42 and the second sheet 46 may themselves be multi-layered polymeric films such as those described in commonly assigned United States Patent No. 5,006,394 issued to Baird on April 9, 1991, and the Patent of the United States No. 5,261,899 issued to Visscher et al. On November 16, 1993, said patents being incorporated herein by reference. The separators 48 can be made of any suitable material to secure the first sheet 42 to the second sheet 46. For example, the separators 48 can be made of a heat-sealable hot-melt adhesive manufactured by Eastman Chemical under the designation Eastobond. A3, or a pressure sensitive adhesive such as HL-1258 manufactured by Fuller Adhesive. The spacers 48 can also be made from a polymer material having a lower melting point temperature than the polymeric material used for either the first sheet 42 or the second sheet 46. The spacers 48 are preferably applied to one of the leaves using a known technique, such as stencil printing, gravure printing, or printing transfer. When a pressure-sensitive adhesive is used, sufficient pressure must be applied to achieve bonding or securing between the separators and the respective sheets. When a heat-meltable adhesive or a polymeric material having a lower melting temperature than the materials used for either the first sheet or the second sheet is used, sufficient heat must be applied to heat the spacers to achieve bonding between the sheets respective. In another preferred embodiment, the spacers 48 can be formed from one or more sheets. The formation can be through embossing, either hot or cold, or molding or other known techniques. The other sheet is then combined with the sheet molded or embossed to form the laminate of the present invention. When used as a topsheet in an absorbent article, such as the topsheet 22 in the sanitary napkin shown in Figures 1 and 2, the first sheet 42 becomes the sheet surface or makes contact with the wearer of the sheet upper, the second sheet 46 becomes the surface that contacts the pad or faces the garment. Accordingly, as the fluid collides with the capillary laminate material 40, it first makes contact with the surface contacting the user 42a of the first sheet 42. The fluid then proceeds through the openings 43 and into the capillary zone. 50. Upon reaching the capillary zone 50, the fluid then moves within the capillary zone 50 under capillary pressure. The fluid moves throughout the capillary zone 50 in both lateral and longitudinal directions. Simultaneously, the fluid passes through the openings 47 in the second sheet 42 and into the acquisition layer 25 • of the sanitary napkin 20, as shown in Figures 1 and 2. The dimensions of the openings 43 and 47 in the first sheet 42 and in the second sheet 46, respectively, they can be substantially identical to each other or can be of - ,. different dimensions. When used as a top sheet or as an acquisition layer, it may be desirable to have openings 43 slightly larger than the openings 47 to provide a capillary gradient within the capillary laminate 40. It may also be desirable to vary the dimensions of the openings 43 and 47 within their respective sheets. For example, when used as a topsheet, it may be desirable to have the openings 43 in the first sheet 42 that are positioned in the central region of the sanitary napkin, i.e. the region surrounding the intersection of the longitudinal and transverse centerlines. , larger than the adjacent openings of the periphery 30 of the sanitary napkin. The difference in dimension can easily be defined from one region to the next, or it can be indistinguishable already "that dimensions can change gradually from one region to the next region.

In addition to varying the size of the openings 43 and 47, it is also possible to vary the frequency of the openings 43 and 47. For example, when used as a top sheet it may be desirable to have a relatively high frequency of openings near the central region as compared to the regions near the periphery of the absorbent article. In general, the minority of the openings and the smallest openings that the largest of the capillary zone defined by the leaves and separators. The dimension of the capillary zone 50 can also be varied for particular uses. For example, if used as a top sheet in an absorbent article, the dimension of the capillary zone 50 may be smaller than if it is used as a top sheet in a sanitary napkin, because the differences in viscosity and density of the urine and menstruation and / or blood. Therefore, the capillary zone for a diaper topsheet will probably be smaller than the capillary zone of a topsheet of sanitary napkins. The frequency, the cross-sectional area, and the height of the separators 48 determine to a substantial degree the dimension of the capillary zone SO. The spacers 48 have a height dimension indicated by the letter "H" in Figure 4. The cross-sectional area of the spacers 48 is determined by taking the cross-sectional area of the spacers in a plane substantially parallel to the first and second sheets 42 and 46, respectively, as indicated by the section lines AA in Figure 3. The dividers 48 are shown as having a circular cross-sectional shape, however, other cross-sectional shapes such as square, rectangular, oval , triangular, bow, dog bone, etc. they can also be used for spacers 48. The side walls 49 of the spacers 48 are shown as being substantially straight along their length in Figures 3 and 4. However, the side walls 4 can be concave or convex or of any shape. other shape such as inclined, curvilinear, etc., as one might wish. Within capillary zone 50 there is at least one or preferably more than a multiplicity of capillary channels, generally designated as 60. Referring now to Figure 3, as the fluid moves between adjacent separators 48, the shape of the capillary channel 60 between the spacers 48 continuously changes. Accordingly, the capillary channels 60 have a non-uniform shape along their length. Referring now to Figure 5, there is shown another embodiment of a capillary laminate 140 of the present invention. The capillary laminate 140 comprises a first fluid-permeable sheet 142 having a plurality of openings 143 therein and a second liquid-permeable sheet 146 having a plurality of openings 147 therein. The first and second sheets are spaced apart from each other by a plurality of spacers 148. Spacers 148 have a substantially rectangular cross section when taken along sectional line AA .. Side walls 149 of spacers 148 are substantially straight . The spacers 148 also serve to connect the first sheet 142 to the second sheet 146. The separators 148 separate the first sheet 142 from the second sheet 146, such that a capillary area 150 is created between the first and second sheets. The capillary zone 150 is divided into a plurality of capillary channels 160. Since the separators 160 are aligned substantially parallel to one another, the capillary channels 160 are substantially straight along their total length. The capillary channels within the capillary zone can acquire any shape as desired. For example, capillary channels can be straight along their total length, straight along only a portion of their length, continuous along their total length, discontinuous along its total length, curvilinear, extending in an arrangement similar to a fan, oval, hourglass, dog bone, asymmetric, etc. In Figure 6 another embodiment of a capillary laminate 170 of the present invention is shown. The capillary laminate 170 is particularly well suited for use as a top sheet in an absorbent article, such as the sanitary napkin 20 of Figure 1. The capillary laminate 170 comprises a first sheet 172 having a plurality of openings 173 there and a second sheet 176 having a plurality of openings 177 therein. The first sheet 172 and the second sheet 176 are spaced apart from one another by a plurality of spacers 178, to define a capillary region 180 between the first and second sheets. Within the capillary zone 180 there is a plurality of capillary channels 190. The dimensions of the capillary zone 180 are substantially non-uniform throughout the length of the capillary laminate as compared to the capillary laminate 140 of FIG. 5, which is according to a substantially uniform capillary region 150. Figure 7 is a perspective illustration, partially segmented, amplified, of another preferred embodiment of the capillary laminated film of Figure 3, which has been formed into a perforated, fiber-like, three-dimensional pattern , macroscopically expanded, 200. The macroscopically expanded web 200 is generally in accordance with the teachings of commonly assigned United States Patent No. 4,342,314, issued to Radel et al., on August 3, 1982, and hereby incorporated by reference. The weft 200 has been found suitable for use as a topsheet 22 in the sanitary napkin 20. The term "macroscopically expanded", when used to describe three-dimensional wefts of the present invention, refers to wefts, strips and films that have been induced to conform to the surface of a three-dimensional forming structure so that both surfaces thereof exhibit a three-dimensional pattern of surface aberrations corresponding to the macroscopic cross-section of said forming structure. Superficial aberrations include such a pattern "that is individually discernible to the naked eye, that is, a simple normal view that has 20/20 vision without the aid of any instrument that changes the appearance of the size or distance of an object or anything else that alter the visual power of the eye, when the perpendicular distance between the eye of the observer and the plane of the frame is approximately 12 inches. The term "fiber-like" as used herein to describe the appearance of the screens of the present invention, generally refers to any fine-scale pattern of openings, random or non-random, cross-linked or non-crosslinked, which connote a appearance and total impression of a woven or non-woven fibrous tissue, when viewed by the human eye. As can be seen in Figure 7, the fiber-like appearance of the wefts is comprised of a continuum of fiber-like elements, the opposite ends of each of the fiber-like elements are interconnected at least one of the other of the other. fiber-like elements. In the embodiment described in Figure 7, the interconnected fiber-like elements form a pattern network of pentagonally formed capillaries 40. The weft 200, which exhibits a fiber-like appearance, modalizes a three-dimensional microstructure extending from the upper surface or surface that contact with the user 205 of the web in the plane 206 to its bottom surface or contact surface of the pad 208 in the plane 209, to promote rapid transport of fluid from the top surface 205 to the bottom surface 208 of the web , without lateral transmission of fluids between capillariesAdjacent 215. As used herein, the term "microstructure" refers to a structure of such fine scale in which its precise detail is easily perceived by the human eye only when amplification occurs through a microscope. another means well known in art. The openings 215 are formed by a multiplicity of "intersecting" fiber-like elements, for example elements 216, 217, 218, 219 and 220, interconnected with each other on the first surface of the weft. Each fiber-like element comprises a base portion, for example the base portion 222, located in the plane 206. Each base portion has a side wall portion, for example the side wall portions 223 attached to each of its base portions. edges. The side wall portions 223 extend generally in the direction of the second surface 208 of the frame. The intersecting sidewall portions of the fiber-like elements are interconnected to one another intermediate the first and second surfaces of the weft, and terminate substantially concurrently with each other in the plane 209 of the second surface. In an especially preferred embodiment, the interconnected side portions terminate substantially concurrent with each other in the plane of the second surface to form openings 225 in the second surface 208 of the frame. The network of capillaries 202 formed by the interconnected side wall portions allows free transfer of fluids from the first surface of the screen directly to the second surface of the screen without lateral fluid transmission between the adjacent capillaries. In addition, small amounts of the fluid are capable of penetrating the openings 243 in the first layer 242 of the capillary laminate 240. The first layer 242 is separated from and secured to the second layer 246 by means of spacers 248 to provide a capillary zone 250 between the first and second leaves. After penetrating the openings 243, the fluid will then move through the capillary zone 250 to the second surface of the weft. Upon reaching the second surface of the weft, the fluid will be withdrawn from the capillary zone 250 and transmitted to the underlying layer. Fluid may also enter openings 247 in second layer 246. Absorbent core 24 may be any absorbent medium that is capable of absorbing or retaining liquids (e.g., menstruation and / or urine). As shown in Figures 1 and 2, the absorbent core 24 has a body surface, a garment surface, side edges and end edges. The absorbent core 24 can be manufactured in a wide variety of sizes and shapes (e.g., rectangular, oval, hourglass, dog bone, asymmetric, etc.) and a wide variety of lipid absorbing materials commonly used in sanitary napkins and other liquid absorbent articles such as shredded wood pulp, which is generally referred to as air felt. Examples of other suitable absorbent materials include folded cellulose wadding; chemically stiffened, modified or crosslinked cellulosic fibers; capillary channel fibers; synthetic fibers such as polyester fibers; peat moss; paper, including paper wrappers and paper laminates; absorbent foams; absorbent sponges; superabsorbent polymers; absorbent gelation materials; or any «equivalent material or combinations of materials, or their mixtures. The configuration and construction of the absorbent core 24 may also be varied (for example, the absorbent core may have zones of variable gauge (eg, profiled, so as to be thicker in the center), hydrophilic gradients, superabsorbent gradients, or areas of acquisition of lower average base weight and lower density, or may comprise one or more layers or structures). The total absorbent capacity of the absorbent core 24, however, must be compatible with the design load and intended use of the sanitary napkin 20. In addition, the size and absorbent capacity of the absorbent core 24 can be varied to accommodate different uses , such as incontinent pads, linings for panties, regular sanitary napkins or sanitary napkins. Exemplary absorbent structures for use as the absorbent core 24 of the present invention are described in U.S. Patent Nos. 4,950,264, issued to Osborn on August 21, 1990; 4,610,678, issued to Weisman et al. On September 9, 1986; 4,834,735, issued to Alemany et al. On May 30, 1989; U.S. Patent No. 5,009,653 issued to Osborne on April 23, 1991; and European Patent Application No. 0 198 683, from The Procter & Gamble Company, published on October 22, 1986 in the name of Duenk and others. Each of these patents is incorporated herein by reference. Alternatively, the absorbent core 24 may comprise a laminated structure comprised of a superabsorbent polymer layer and one or more sheets or fabrics of crosslinked fibers. Crosslinked cellulosic fibers suitable for the absorbent core 24 are described in U.S. Patent No. 4,888,093 issued to Cook et al. On December 19, 1989; U.S. Patent No. 4,822,543 issued to Dean et al. on April 18, 1989; U.S. Patent No. 4,889,595 issued to Schoggen et al. on December 26, 1989; and U.S. Patent No. 4,898,642 issued to Moore et al. on February 6, 1990; U.S. Patent 4,935,022 issued June 19, 1990 to Lash et al .; European Patent Application Publications Nos. 0 427 316 A2 and 0427 317 A2, published in the name of Herrón et al. on May 15, 1991; and European Patent Application Publication No. 0 429 112 A2 published in the name of Herron et al. on May 29, 1991 incorporated herein by reference. The laminate of a sheet of crosslinked cellulose fibers wrapping the layers of particles of absorbent gelation material can be formed. The sheet is wrapped to "appear as having a" C "configuration when viewed from the end. The wrapped sheet forms an upper layer and a lower layer. In alternate embodiments, the laminate can be formed in many other ways, such as by providing separate wefts of cross-linked cellulosic material (or other absorbent material) for the different layers of the laminated absorbent core different from a single sheet, or by providing it with layers additional In this type of core, the cellulose fibers are cross-linked and preferably < rigidly stiffened, twisted, curled, to provide fibers that can be used in sheet form as the absorbent core. The preperation of appropriate, chemically stiffened, twisted cellulosic fibers, from which chemically stiffened, twisted, refined cellulosic fibers can be prepared, used in detail in U.S. Patent Nos. 4,888,903; 4,822,543; 4,889,595; 4,889,597; 4,889,596; and 4,898,642. The use of such fibers in combination with absorbent gelation materials, and means for making such combinations, are described in U.S. Patent No. 4,935,022. Such preparations typically involve the use of aldehydes, such as glutaraldehyde, as the linking agent. In addition, the carboxylic acids can be used as linking agents. It will be appreciated that other means for preparing other linked cellulosic fibers are also known, and such fibers can also be used herein, although the properties of fluid absorbency may be suboptimal when compared to the aforementioned fibers. Reference may be made to various mentions in U.S. Patent No. 4,898,642 and PCT / US89 / 01581 for other types of fibers. Once in hand, the crimped cellulosic fibers are refined to provide the fibers used to prepare the preferred absorbent cores used in the practice of the present invention.

Alternatively, the absorbent core may comprise a capillary laminate. When used as an absorbent core, the dimension and frequency of the openings in the first and second leaves, and the dimensions, height and frequency of the separators may be somewhat different than those of a capillary sheet material "that is used as a sheet higher. For example, the capillary zones may be somewhat larger to enable the capillary laminate to retain larger amounts of fluid. The absorbent gelation materials can be extended around the lateral and transverse edges of the capillary laminate to retain the fluid within the capillary laminate. Alternatively, the capillary laminate can be used as a portion of an absorbent core, where the capillary laminate is placed on a bed or layer of absorbent or superabsorbent gelation materials. In Figures 8 and 9 another preferred embodiment of a capillary laminate 340 of the present invention is shown. The capillary laminate comprises a first sheet 342 and a second sheet 346 secured together and separated apart by a plurality of spacers 348. The first sheet 342 includes a plurality of openings 343. The second sheet 346 is substantially non-perforated, therefore preventing the fluids are transmitted through it. The capillary laminate 340 may be particularly useful as a macroscopically expanded top sheet, such as that shown in Figure 7, where the second sheet 346 is not desired or required to be fluid. Alternately, the capillary laminate 340 can also be used as an absorbent core where the second sheet 346 is impervious to liquids and can therefore assist the backsheet in protecting against soiling of undergarments or clothing. In Figure 10 another perferred embodiment of a capillary laminate 370 of the present invention is shown. The capillary laminate 370 includes a first sheet 372 secured to a second sheet 376 by a plurality of separators 375. The sheet 372 has a plurality of openings 373 therein. The second blade 376 has a plurality of openings 377. A capillary region 374 is provided between the first blade 372 and the second blade 376. The capillary laminate 370 also includes a third blade 380 secured to the second blade 376 by spacers 379. capillary zone 378 is provided between second sheet 376 and third sheet 380.

The third leaf 380 preferably has no openings therein. The capillary laminate 370 can be formed into a weft macroscopically similar to that shown in Figure 7. Preferably, the capillary laminate 370 will be used as an absorbent core in an absorbent article. By increasing the layers of the capillary laminated film, the capillary laminated film is able to retain and store more fluids. The particular number of layers is more limited and can be designed to handle the projected volumes of fluid. The backsheet 23 is impermeable to liquids (eg, menstruation and / or urine) and is preferably manufactured from a thin plastic film, although other flexible, liquid impervious materials may also be used. As used herein, the term "flexible" refers to materials that are deformable and will readily conform to the general shape and contour of the human body. The backsheet 23 can thus comprise a woven or non-woven material, polymeric films such as polyethylene or polypropylene thermoplastic films, or combined materials such as a film-coated nonwoven material. Preferably, the backsheet 23 is a polyethylene film having a thickness of about 0. 012 mm (0.5 mil) to about 0.051 mm (2.0 thousandths of an inch). Exemplary polyethylene films are manufactured by Clopay Corporation of Cincinnati, Ohio, United States, under the designation P18-0401 and by Ethyl Corporation, Vis "queen division, of Terre Haute, Indiana, United States, under the designation XP-39385. The backsheet 23 is preferably highlighted and / or matte finished to provide a more cloth-like appearance. Further, the backsheet 23 can allow "vapors to escape from the absorbent core 24 (ie, it is able to breathe) but at the same time prevents the exudates from passing through the backsheet 23. In use, the sanitary napkin 20 can be maintained in place by any means of support or well-known joining means for such purposes. Preferably, the sanitary napkin is placed in the wearer's undergarments or panties and secured thereto by a fastener such as an adhesive 36. The adhesive 36 provides means for securing the sanitary napkin 20 in the crotch portion of the panties. Accordingly, a part or all of the outer surface of the backsheet 23 is coated with adhesive. Any adhesive or glue used in the art for this purpose can be used as the adhesive herein, with pressure sensitive adhesives being preferred. Suitable adhesives are Century A-305-IV, manufactured by Century Adhesives Corporation of Columbus, Ohio, and Instant Lock 34-2823, manufactured by National Starch and Chemical Company, of Bridgewater, New Jersey, United States. Suitable adhesive fasteners are also disclosed in U.S. Patent No. 4,917,697. Before the sanitary napkin is put into use, the pressure sensitive adhesive 36 is typically covered with a removable liner 37, removable, so as to prevent the adhesive 36 from drying or adhering to a surface other than the crotch portion of the adhesive. the panties before use. Suitable release liners 37 are also described in the above-referenced U.S. Patent No. 4,917,697. Any commercially available peel-off liners, commonly used for such purposes, may be used herein. Non-limiting examples of suitable release liners are BL30MG-A Silox El / p and BL30MG-A Silox 4P / 0, both manufactured by Akrosil Corporation, of Menasha, Wisconsin, United States. The sanitary napkin 20 of the present invention is used by removing the release liner 37 and subsequently placing the sanitary towel 20 on a panty so that the adhesive 36 contacts the panty. The adhesive 36 holds the sanitary napkin in its position within the pant during use. The sanitary napkin 20 may also be provided with two fins 34, each of which are adjacent to and extending laterally from the side edges of the absorbent core. The fins 34 are configured to dress over the edges of the wearer's panties in the crotch region so that the fins 34 are disposed between the edges of the wearer's panties and the thighs. The fins 34 serve at least two purposes.

The first, the fins 34 help to prevent swelling of the user's body and the panties by the menstrual fluid, preferably by forming a double wall barrier along the edges of the panty. Second, the fins 34 are preferably provided with attachment means on their garment surface so that the fins 34 can be folded back under the panties and attached to the side facing the garment of the panty. In this way, the fins 34 serve to maintain the sanitary towel 20 properly placed on the pantyhose. The fins 34 may be constructed of various materials, including materials similar to the topsheet, backsheet, paper or combinations of these materials. In addition, the fins 34 can be a separate element attached to the main body portion of the towel or can comprise extensions of the upper sheet 22 and the back sheet 23 (ie, unitary). A number of sanitary napkins having suitable or adaptable fins for use with the sanitary napkins of the present invention are described in U.S. Patent No. 4,687,478 entitled "Shaped Sanitary Napkin With Flaps", issued to Van Tilburg on August 18. of 1987; U.S. Patent 4,589,876 entitled "Sanitary Napkin" issued to Van Tilburg on May 20, 1986; and U.S. Patent 4,608,047 entitled "Sanitary Napkin Attachment Means" issued to Medingly on August 26, 1986. In a preferred embodiment of the present invention, an adhesion layer or layers can be placed between the top sheet and the absorbent core. The acquisition layer can serve several functions, including improving the passage of exudates on and towards the absorbent core. There are several reasons why it is important to improve the passage of exudates, including providing a more even distribution of the exudates throughout the absorbent core, and allowing the sanitary napkin 20 to be made relatively thin. (The fluid passage referred to herein, may include the transport of liquids in one, two or all directions (ie, in the x-y plane and / or in the z-direction)). The acquisition layer may be comprised of several different materials including woven or non-woven webs of synthetic fibers, including polyester, polypropylene, or polyethylene, natural fibers including cotton or cellulose; mixtures of such fibers, or any material and quivalent or combinations of materials. Examples of sanitary napkins "having an acquisition layer and a topsheet are fully described in U.S. Patent 4,950,264, issued to Osborn, and U.S. Patent Application Serial No. 07 / 810,774," Absorbent Article Having Fused Layers ", presented on December 17, 1991, in the name of Cree and others. Each of these references are incorporated herein by reference. In a preferred embodiment, the acquisition layer may be joined to the topsheet by any of the conventional means for joining together webs, most preferably via fusion links as described more fully in the above-referenced Cree application. Alternatively, the adsorption layer may comprise a capillary laminate. When used as a core acquisition layer, the size and frequency of the openings in the first and second leaves, and the dimension, height and frequency of the spacers may be somewhat different than those of a capillary laminate material that is used as a top sheet or an absorbent core. Although particular embodiments of the present invention have been illustrated and described, it will be obvious to those skilled in the art that various other changes and modifications may be made without departing from the spirit and scope of the invention. It is therefore intended to cover in the appended claims all those changes and modifications that are within the scope of this invention.

Claims (13)

1. NOVELTY OF THE INVENTION CLAIMS 1. A laminated material characterized by: a first sheet and a second sheet, said first sheet being permeable to fluids, said pir was sheet and said second sheet being separated apart from each other by at least one separator to define a capillary zone for the capillary movement of the fluid therough, said separator connecting said first sheet and said second sheet together to form said laminate material.
2. 2. The laminated material according to claim 1, further characterized by "that said first sheet includes a plurality of openings.
3. 3. The laminated material according to claim 1 or 2, further characterized in that said second sheet is permeable to fluids.
4. 4. The laminated material according to claim 3, further characterized by "that said second sheet includes a plurality of openings.
5. The laminated material according to claim 4, further characterized in that said openings in said first sheet are larger than said openings in the second sheet.
6. 6. The laminated material according to claim 1, further characterized in that said second sheet is impermeable to fluids.
7. 7. The laminated material according to any one of the preceding claims, further characterized in that said first sheet and said second sheet are comprised of a polymeric material.
8. The laminated material according to any of the preceding claims, further characterized in that said laminate includes a plurality of separators.
9. 9. The laminated material according to any one of the preceding claims, further characterized in that said capillary zone includes a plurality of channels.
10. 10. The laminated material according to claim 9, further characterized by "that said channels are substantially non-uniform along their length.
11. 11. The laminated material according to claim 9, further characterized by "that said channels are substantially uniform along their length.
12. The laminated material according to any of the preceding claims, further characterized in that said capillary zone is substantially uniform throughout the length of said laminated material.
13. 13. The laminated material according to any one of the preceding claims, further characterized by "that said capillary zone is substantially non-uniform throughout the length of said laminate. EXTRACT OF THE DISCLOSURE The present invention relates to a laminated material. The laminated material includes a first sheet and a second sheet separated apart from one another by means of spacers to define a capillary zone for capillary movement of the fluid between the first and second sheets. The spacers are connected to the first sheet and the second sheet together to form the laminate.