ABSORBENT ARTICLES CONTAINING ANTIBACTERIAL AGENTS IN THE SU.PERIOR SHEET FOR ODOR CONTROLTECHNICAL FIELDThe present invention relates to the incorporation of zeolite, impregnated with a heavy metal, into an upper sheet of perforated plastic film of catamenial products - "" "'to provide an improvement in odor control, ie, a decrease in odor perspiration preventing the formation of bad odor. By placing the antibacterial agent in the opening of the upper sheet, the antibacterial agent is in the closest possible proximity to the perspiration produced on the wearer's skin.
BACKGROUND OF THE INVENTIONA wide variety of fluid-absorbing structures known in the art absorb body fluids such as blood, urine, menstruation, and the like, and are hygienic and comfortable to wear. Disposable products of this type generally comprise a fluid pervious top sheet material, a fluid absorbent core, and a fluid impermeable backsheet material. Various shapes, sizes and thicknesses of such items have been examined in an attempt to make their use more comfortable and convenient. Odor control in hygienic products has beenresearch object for many years. Various body fluids have an unpleasant odor, or develop such odors when they come in contact with air and / or bacteria for extended periods of time. Multi-active articles are known in the art C '^ and are intended to provide an odor reduction. Frequently, multi-active systems do not eliminate sweaty odors. Several odor control agents have been reported in the literature. The Patent E.U.A. No. 2,690,415, Shuler, issued on September 28, 1954, shows films of odor absorbing materials uniformly bound in the interstices of an adhesive permeable web to provide an odor absorbing medium, eg, catamenial products. Note the particulate carbon, silica gel and activated alumina. The changes and displacement of the particles is assertively avoided and the blade is flexible. The ABSCENTS (Union Carbide odor control molecular stencil) for use in diapers and cataminals are specifically noted in the Union Carbide brochure. (AJ Gioffre 5 1988). The brochure indicates that the study of UC markets shows potential benefits in such products. US Patents Nos. 4,795,482 and 4,826,497 refer to ABSCENTS used as an odor control agent, generally, and in hygienic products, in particular.
Although the materials of zeolite, coal, etc. they effectively control many odors associated with body fluids, these do not provide optimal control for odor transpiration. In addition, perspiration often remains on the top of the pad. Therefore, to color the antibacterial active in the topsheet, the present invention provides an asset placement in close proximity to the same perspiration.
The perforated top sheets provide several benefits such as fast passage of the fluids discharged through the top sheet and into the absorbent core.
Also these upper sheets, which by themselves do not absorb fluids, and which are designed to prevent rewetting again as a result of the return of fluids through the upper sheet, provide a more hygienic surface and increase or improve the comfort of the consumer. Finally, the perforated top sheets provide an increased surface area available for external body fluids that come into contact. Therefore, the object of the present invention is to provide an article of manufacture, that is, a panty liner and / or a sanitary napkin, where the upper sheet provides an improved control of the perspiration odor by placing the active in the closest proximity to the user's skin and by incinerating the surface area of the upper sheet to make with the odorant materials.
SUMMARY OF THE INVENTION"~ Accordingly, the present invention provides an article of manufacture that minimizes the odor caused by body fluids, i.e. transpiration, comprising: A. a liquid-permeable top sheet B. a liquid-impermeable top sheet C. an absorbent core positioned between the top sheet and the backsheet, and D. optionally, a means for supporting the article in a suitable position to perform its function of smell and odor control, where the top sheet comprises a perforated plastic film containing an effective amount of zeolite impregnated with a heavy metal ion, preferably the perforated plastic film is selected from the group consisting of a thermoplastic film with a formed aperture, cross-linked thermoplastic film, a thermoplastic fabric, and mixtures thereof;preferably the upper sheet comprises an elastic three-dimensional screen, showing an appearance and a fiber-like tactile impression and comprises a plastic material impervious to fluids, said frame having a first and second surface, the first surface having a multiplicity of openings in it. it, each of the openings being defined by a multiplicity of intersecting fiber-like elements interconnected to each other in the plane of the first surface, each of the fiber-like elements showing a substantially uniform U-shaped cross section to along its length, the cross section comprising a base portion in the plane of the first surface and a side wall portion attached to each edge of the base portion, the side wall portions extend generally in the direction of the second surface of the weft, the portions of the intersected side walls are interconnected to each other intermediate the first and second surface of the frame, the portions of the interconnected side walls substantially substantially concurrently with one another in the plane of the second surface. Preferably the zeolite impregnated with a heavy metal ion is uniformly distributed throughout the material of the topsheet. The articles of the present invention provide an increase in the surface area of the upper sheet for contact with external body fluids such as perspiration, which places the antibacterial active in close proximity to the wearer's skin, the active reducing the bad smell of perspiration minimizing its formation.
BRIEF DESCRIPTION OF THE DRAWINGSWhile the description concurs with the claims that particularly emphasize that and distinctly claim the present invention, the following description will further illustrate the present invention. Figure 1 is a plan view of an absorbent article of the present invention in its flat condition with a perforated top sheet contacting the body containing an antibacterial agent with portions of the sanitary towel cut off. Figure 2 is a cross-sectional view of an absorbent article comprising a perforated top sheet containing an antibacterial agent. Figure 3 is an enlarged photograph of a segment of a three-dimensional top sheet of the type generally illustrated in Figures 1 and 2.
DETAILED DESCRIPTION OF THE INVENTIONThe present invention relates to an article of manufacture that minimizes odor caused by bodily fluids, i.e. transpiration, comprising: A. a liquid-permeable top sheet B. a liquid-impermeable top sheet C. an absorbent core placed between the top sheet and the back sheet; and D. Optionally, a means for supporting the article in a suitable position to carry out its function of odor control and odor control; wherein the top sheet comprises a perforated plastic film containing an effective amount preferably of from about 0.05% to about 4%, more preferably from about 0.5% to about 2% of zeolite impregnated with a heavy metal ion; preferably the perforated plastic film is selected from the group consisting of a thermoplastic film with formed aperture, hydroformed thermoplastic film with apertures, crosslinked thermoplastic film, a thermoplastic fabric, and mixtures thereof; more preferably the upper sheet comprises an elastic three-dimensional screen, showing a fiber-like appearance and a tactile impression and comprised of a plastic material impermeable to fluids, said frame having first and second surface, the first surface having a multiplicity of openings in it, each of the openings being defined by a multiplicity of intersecting fiber-like elements, interconnected to each other in the plane of the first surface, each of the fiber-like elements furthermore showing a substantially uniform U-shaped cross section along its length, the cross section comprising a base portion in the plane of the first surface and a side wall portion attached to each edge of the base portion, the side wall portions extend generally in the direction of the second surface of the frame, the portions of the side walls intersected the intermediate portions of the interconnected side walls being substantially interconnected with one another in the plane of the second surface being interconnected one to the other intermediate of the first and second surface of the frame. Preferably the metal ion is selected from the group consisting of silver, zinc, copper, and mixtures thereof. The zeolites of the upper sheet are selected from the group consisting of zeolite type A (Si02 / A1203 = 1.4 to 2.4), zeolite type X (Si02 / A1203 = 2 to 3), zeolite type Y (Si02 / A1103 = 3 to 6) ), and mixtures thereof. The preferred zeolites are synthetic type A zeolites, type X zeolites and mixtures thereof.
The zeolite carrier in the top sheet of the articles of the present invention comprises an aluminate / silicate system, with associated actions M, which provide total electrical neutrality. Empirically, the zeolite system can be represented as XA102 and Si02 and the electrically neutral zeolite as x / riM. XA102. and Si02.zH20 where: x and y are each integer, M is an ion exchangeable metal ion, which is usually the ion of a monovalent or divalent metal and n is the valence of the metal. As noted by the empirical formula, the zeolites may also comprise water of hydration (zH20). The zeolites of the upper sheet are selected from the group consisting of a zeolite type A (Si02 / A1203 = l .4 a2. 4), type X zeolite (Si02 / A1203 = 2 to 3), Y type zeolite(Si02 / Al203 = 3 to 6), and mixtures thereof. Preferred zeolites are synthetic type A zeolites, type X zeolites and mixtures thereof. In addition to the above sources of prior zeolites, the polyethylene (low density) film containing about 2% of a silver / zinc mixture is available from Kanebo USA under the tradename "film"LDPE Bactikiller AZ. Optionally, the absent core of the articles of the present invention comprises an effective amount of an auxiliary odor control agent, preferably from about 0.01 g to about 15 g per article, more preferably from about 0.1 g to about of 10.0 g per aticle, the auxiliary odor control agent selected from the group consisting of: a. zeolite; b. activated carbon; c. Silica gel; d. encapsulated perfume that is activated with moisture; and. cyclodextrin; F. activated alumina; and g. mixtures of them. The articles of the present invention can be made by components that are well known in the art.
Also, methods and apparatus for assembling catamenial products are also known in the art. With the intention of not limiting, the following exemplifies the articles of the present invention. As used herein, the term "absorbent article" refers to devices that absorb and contain body exudates, and, more specifically, refers to devices that are placed against or in proximity to the user's body to absorb and contain various exudates discharged from the body. A "unitary" absorbent article refers to absorbent articles that are formed of separate parts joined together to form a coordinated entity such that separate manipulation parts such as a separate fastener and pad are not required. A preferred embodiment of a disposable unitary absorbent article of the present invention is the catamenial pad, sanitary napkin 20, which is shown in Figure 1. As used herein the term "sanitary napkin" refers to an absorbent article that is used or placed by women adjacent to the pudenda region, usually external to the genital uro region, and which is intended to absorb and contain menstrual fluids and other vaginal discharges from the user's body (ie, blood, menstruation, and urine) . Interlabial devices that reside partially within and partially external to the user's lobby are also within the scope of this invention. As used herein, the term "pudendal" refers to the externally visible female genital region. It should be understood, however, that the present invention also applies to other feminine and catamenial pads such as underpants, or other absorbent articles such as incontinence pads, and the like. Figure 1 is a plan view of a sanitary napkin 20 of the present invention in its planar state with portions of the structure being cut away to more clearly show the construction of the sanitary napkin 20 and with the portion of the sanitary napkin 20 that on face or makes contact with the user, oriented towards the observer. As shown in Figure 1, the sanitary napkin 20 preferably comprises a liquid permeable upper sheet 22, a liquid impermeable backsheet 23, bonded with the upper sheet 22, an absorbent core 24 and a secondary upper sheet 27 placed between the upper sheet 22 and the back sheet 23. The sanitary napkin 20 has two surfaces, a surface that makes contact with the body or "body surface" 20a and a garment surface 20b. The sanitary napkin 20 is shown in Figure 1 as seen from its body surface 20a. The body surface 20a is intended to be worn adjacent to the wearer's body while the garment surface 20b is on the opposite side and is intended to be placed adjacent to the wearer's undergarment when the sanitary napkin 20 is use The sanitary napkin 20 has two center lines, a longitudinal center line L and a transverse center line T. The term "longitudinal", as used herein, refers to the line, axis or direction in the plane of the sanitary napkin 20 that is generally aligned with (eg, approximately parallel to a vertical plane that bisects a user. standing on the right and left halves of the body when the sanitary napkin 20 is used The terms "transverse" or "lateral" as used herein are interchangeable and refer to the line, axis or direction falling within the plane of the sanitary napkin 20, which is usually perpendicular to the longitudinal direction, 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 longitudinal edges they are designated 31 and the end edges are designated 32. Although the top sheet, the back sheet, and the absorbent core can be assembled in a variety of well-known configurations (i Including the so-called "tube" products or side flap products), preferred sanitary napkin configurations are generally described in US Pat. 4,950,264. "Thin, Flexible Sanitary Napkin" Osborn, issued on August 21, 1990; EU.A. Patent 4,425,130, "Compound Sanitary Napkin", DesMarais, issued January 10, 1984; Patent E.U.A. 4,321,924, "Boardered Disposable Absorbent Article" Ahr, issued March 30, 1982: Patent E.U.A. 4,589,876"Shaped Sanitary Napkin With Flaps", Van Tilburg, issued August 16, 1987. Each of these patents is incorporated herein by reference. Figure 1 shows a preferred embodiment of the sanitary napkin 20 in which the topsheet 22 and the backsheet 23 have length and width dimensions generally larger than those of the absorbent core 24. The topsheet 22 and the backsheet 23 are They extend beyond the edges of the absorbent core 24 to thereby form not only the periphery portions but also lateral fins or wings 34. Figure 2 is a cross-sectional view of the sanitary napkin 20 taken along the length of the line section 2-2 of figure 1. Figure 2 shows the upper secondary sheet 27, just below the upper sheet 22. The wing 34 is an extension of the upper sheet 22. The fastening means 36 together with the layer of release 37 hold the absorbent article in place in such a way that it can be carried out the function that is proposed. Figure 3 is an enlarged plan view photograph approximately 27 times its current size of a preferred embodiment of the three dimensional, fiber-like, liquid-permeable topsheet of the present invention. As can be seen in the amplified photo of figure 3, the fiber-like appearance of the weft is comprised of fiber-like continuous elements, each- * - end of the fiber-like elements are interconnected at least one of each of said fiber-like elements. The upper sheet 22 of fiber-like plastic is particularly suitable for use as a top sheet in the sanitary napkin of the type generally illustrated in Figure 1. Figure 3 is an illustration of the body surface 20a of the top sheet 22. The sheet upper 22, which shows a fiber-like appearance, modulates a three-dimensional microstructure comprising a regulated, continuous, diminishing size capillary network that extends from the highest position or body surface 20a to the lower part or surface of the garment 20b of the same to promote the rapid transport of liquids from the body surface 20a to the garment surface 20b surface of the upper sheet without lateral transmission of said liquid between the adjacent capillary networks. A typical capillary network of the type generally shown in Figure 3 comprises upper capillary openings 38 formed by a multiplicity of primary fiber-like elements, i.e. elements. The topsheet 22 is docile, soft in feel, and non-irritating to the wearer's skin. In addition, the topsheet 22 is permeable to liquids allowing liquids (eg, menstruation and / or urine) to easily penetrate through its thickness. A suitable top sheet 22 is made of materials such as perforated formed thermoplastic films, perforated plastic films, perforated hydroformed thermoplastic films; crosslinked thermoplastic films; and thermoplastic fabrics. The top sheets of the present invention are described in detail in the US Pat. 4,342,314 entitled "Resilient Plástic Web Exhibiting Fiber-Like Properties", Radel et al., Issued August 3, 1982, which is incorporated herein by reference, especially column 4, line 41 to column 6, line 44. Preferred methods for making the upper sheets of the present invention are disclosed in EUAP 4,637,819, Quellette et al., issued January 20, 1987 and EUAP 4,839,216, Curro and others issued June 13, 1989, which are incorporated herein by reference. by reference. The perforated upper sheets of the present invention are permeable to body exudates and more non-absorbent and have a reduced tendency to allow liquids to return through and rewet the user's skin. In this way, the surface of the perforated upper sheet which is in contact with the body remains dry, thereby reducing the body soiling and creating a more comfortable feeling for the user. Other films formed are described in the patent E.U.A. 3,929,135, entitled "Absorptive Structures Having Tapered Capillaries" Thompson, which were issued on December 30, 1975; Patent E.U.A. 4,324,246 titled "Disposable Absorbent Article Having A Stain Resistant Topsheet", Mullane et al., Issued April 13, 1982; Patent E.U.A. 4,463,045 entitled "Macroscopically Expanded Three-Dimensional Plástic Web Exhibiting Non-Glossy Visible Surface and Cloth-Like Tactile Impression," Ahr et al., Issued July 31, 1984; and E.U.A. 5,006,394"Miltilayer Polymeric Film", Baird, issued April 9, 1991. Each of these patents is incorporated herein by reference. Other preferred top sheets for the present invention are described of film described in one or more of the above patents and sold in sanitary napkins by The Procter & Gamble Company of Cincinnati. Ohio as "DRI-WEAVE". In a preferred embodiment of the present invention, the body surface of the topsheet is hydrophilic to assist the liquid to transfer it through the topsheet faster than if the body surface were not hydrophilic. This will decrease the likelihood that menstrual fluid and perspiration will flow out of the upper sheet rather than flowing into and being absorbed by the absorbent core. In a preferred embodiment, the surfactant is incorporated into the polymeric materials of the formed film topsheet as described in the U.S. Patent Application. Serial No. 07 / 794,745, "Absorbent Article Having A Nonwoven and Apertured Film Coversheet," Aziz, et al., Filed November 19, 1991, which is incorporated herein by reference herein.
Alternatively, the body surface of the topsheet can be made hydrophilic by treating it with a surfactant such as described in the above reference E.U.A. 4,950,254, incorporated herein by reference. The absorbent core 24 can be any absorbent medium that is capable of absorbing or retaining liquids (e.g., menstruation and / or urine). The absorbent core 24 can be manufactured in a wide variety of sizes and shapes (eg, rectangular, oval, hourglass, dog bone, asymmetrical, etc.) and a wide variety of absorbent liquid materials commonly used in sanitary napkins and other absorbent articles such as pulped wood pulp fibers which is generally referred to as an air filter. Examples of other suitable absorbent materials include folded cellulose wadding; melted and blown polymers including coform; crosslinked or modified cellulose fibers, chemically hardened; synthetic fibers such as crimped polyester fibers; mold peat; gauze gauze wraps and gauze laminates; absorbent foams; absorbent sponges, superabsorbent polymers; absorbent gelation materials; or any equivalent material or combinations of materials, or mixtures thereof. The configuration and construction of the absorbent core can also be varied (for example, the absorbent core can have varied zones of calibrators (for example, profiled in such a way that they are thicker in the center), hydrophilic gradients, superabsorbent gradients, or zones of acquisition of lower average and lower average weight, or may comprise one or more layers or structures). The total absorbent capacity of the absorbent core must, however, be compatible with the design load and the intended use of the sanitary napkin. In addition, the size and absorbent capacity of the absorbent core can be varied to accommodate different uses such as incontinence pads, pantiliners, regular sanitary napkins, or nighttime sanitary napkins. Exemplary absorbent structures for use as the absorbent core of the present invention are described in US Pat. 4,950,264 titled "Thin, Flexible Sanitary Napkin" issued to Osborn on August 21, 1990 which is incorporated herein by reference. A preferred embodiment of the absorbent core of the present invention optionally comprises an effective amount of an adjunct auxiliary odor control agent, preferably from about 0.01 g to about 15 g per article, more preferably from about 0.1 g to about 10.0 g per article, the auxiliary odor control agent is selected from a group consisting of: a. zeolite; b. activated carbon; c. Silica gel; d. encapsulated perfume activated by moisture; and. cyclodextrin; F. activated alumina; and g. mixtures thereof. The backsheet 23 and the topsheet 22 are positioned adjacent the garment surface 20b and the body surface 20a, respectively, of the absorbent core 24 and are preferably attached thereto and to each other by attachment means (not shown) such as those well known in the art. For example, the backsheet 23 and / or the topsheet 22 can be secured to the absorbent core 24 or to each other by a uniform continuous layer of adhesive, an adhesive layer pattern, or an array of separate, spiral, or dotted lines. of adhesives. The adhesives that have been found satisfactory are manufactured by H.B. Fuller Company of St. Paul, Minnesota under the designation HL-1258 or H-2031. Preferably, the joining means will comprise an open network pattern or adhesive filaments as disclosed in US Pat. 4,573,986 entitled "Disposable Waste-Containment Garment", issued to Minetola, and others on March 4, 1986, and which is incorporated herein by reference. An exemplary joining means of an open network pattern of filaments comprises several lines of adhesive filaments twisted in a spiral pattern such as that illustrated by the apparatus and method shown in US Pat. 3,911,173 issued for Sprague, Jr. on October 7, 1975; Patent E.U.A. 4,785,996 issued to Zieker, and others on November 22, 1978; and Patent E.U.A. 4,842,666 issued to Werenicz on June 27, 1989. Each of these patents is incorporated herein by reference. Alternatively, the joining means may comprise heat bonds, pressure joints, ultrasonic joints, mechanical dynamic joints; or any other suitable joining means or combinations of these joining means as are known in the art. The backsheet 23 is permeable to liquids (eg, menstruation and / or urine) and is preferably made of thin plastic film, although other flexible liquid permeable materials may also be used. As used herein, the term "flexible" refers to materials that are docile and comfortable to the general shape and contour of the human body. The backsheet 23 prevents the exudates absorbed and contained in the absorbent core 24 from wetting articles that contact the sanitary towel 20 such as pants, pajamas and underwear. The backsheet 23 may therefore comprise a woven or non-woven material, polymeric films such as polyethylene or polypropylene thermoplastic films, or composite materials such as a film covered with nonwoven material. Preferably, the backsheet is a polyethylene film with a thickness of about 0.012 mm (0.5mil) to about 0.051 mm (2.0 mils). Exemplary polyethylene films are manufactured by Clopay Corporation of Cincinnati, Ohio, under the designation P18-0401 and by Ethyl Corporation, Visqueen Division, of Terre Haute, Indiana, under the designation XP-39385. The back sheet is engraved and / or with matte finish to provide a more dress appearance. In addition, the backsheet 23 can allow vapors to escape from the absorbent core 24 (i.e., breathable) while still preventing passage of the exudates through the backsheet 23. In use, the sanitary napkin 20 can remain in place by any support means, fastening means, or joining means 3b well known for such purposes. Preferably, the sanitary napkin is placed in the wearer's underwear or panties and secured thereto by a fastener such as the adhesive. The adhesive provides a means for securing the sanitary napkin in the central portion of the panty. Accordingly, a portion of all the external surfaces of the backsheet 23 is covered with adhesive. Any adhesive or glue used in the art for such purposes can be used by the adhesive herein, preferably with pressure sensitive adhesives. Suitable adhesives are Century A-305-IV manufactured by Century Adhesives Corporation of Columbus, Ohio; and Instant Lock 34-2823 manufactured by the National Starch and Chemicals Company of Bridgewater, NJ. Suitable adhesive fasteners are also described in the U.S. Patent. 4,917,697 incorporated herein by reference. Before the sanitary napkin is placed for use, the pressure sensitive adhesive is typically covered with a removable release liner 37 to prevent the adhesive from drying or adhering to the surface in a portion other than the central portion of the panty Before its use. Suitable release liners are also described in the aforementioned US Patent E.U.A. 4,917,697. Any commercially available release liner commonly used for such purposes may be used herein. Non-limiting examples of suitable release liners are BL30MG-A, Silox E1 / 0IBL30MG-A, Silox 4P / 0, both being manufactured by Akrosil Corporation of Menasha, Wl. The sanitary napkin 20 of the present invention is used by removing the release liner and subsequently placing the sanitary napkin on a panty so that the adhesive makes contact with the panty. The adhesive holds the sanitary napkin in position during the use of the panty. In a preferred embodiment of the present invention, the sanitary napkin has two fins 34, each of which is adjacent to and extending laterally from the lateral edge to the absorbent core. The fins are configured to overlap the reverse of the edges of the wearer's panties in the central region such that the fins are positioned between the edges of the wearer's panties and the thighs. The fins serve three purposes. First, the fins serve as an aid in preventing staining of the user's body and underpants by the menstrual fluid, preferably by forming a double-walled barrier along the edges of the panty. Second, the fins are preferably provided with attachment means on their garment surface so that the fins can unfold backwards under the panty and join the side facing the garment of the panty. In this way, the fins serve to keep the sanitary napkin properly positioned in the pantyhose. Finally, the finned articles have increased their surface area of the top sheet in such a way that potentially a greater amount of zeolite impregnated with a heavy metal ion will come into contact with the odoriferous materials, i.e. the sweat. ÍC "The fins can be constructed of various materials including materials similar to the upper sheet, rear sheet, toilet paper, or combinations of these materials, however it is preferably constructed from the materials of the upper sheet.constructed from a perforated film top sheet of the present invention, then the zeolite impregnated with heavy metal ions, can be incorporated into the top layer of the fins. In addition, the fins can be a separate element attached to the main body of the towel or canunderstand extensions of the upper sheet and back sheet (that is, 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 4,687,478, entitled "Shaped Sanitary.
Napkin With Flaps ", which was issued to Van Tilburg on August 18, 1987, United States Patent 4,589,876 entitled" Sanitary Napkin "which was issued to Van Tilburg on May 20, 1986, and the Patent of the United States. U.S. 4,608,047 entitled "Sanitary Napkin Attachment Means", which was issued to Mattingly on August 26, 1986, all being incorporated herein by reference In a preferred embodiment of the present invention, an acquisition layer (s) 27 may be placed between The upper sheet and the absorbent core The acquisition layer 27 can serve several functions including improving the twisting of exudates on and towards the absorbent core There are several reasons why improved twist of exudates is important, including providing a distribution more uniformly of the exudates throughout the entire absorbent core and allowing the sanitary napkin 20 to be made relatively thin. (The twisted here refers to which can encompass transportation 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 cotton or cellulose; mixtures of such fibers; or any equivalent material or combinations of materials. Examples of sanitary napkins having an acquisition layer and an upper sheet are more fully described in U.S. Patent 4,950,264 issued to Osborn and U.S. Patent Application Serial Number 07 / 810,774"Absorbent ArticlesHaving Fused Layers ", filed on December 17, 1991, in the name of Cree et al. All of the above references are incorporated herein by reference.In a preferred embodiment, the acquisition layer may be attached to the top sheet by any conventional means for joining frames together, most preferably by fusion joints as described more in detail in the above-mentioned Cree application Although particular embodiments of the present invention have been illustrated and described, several other changes and modifications can be made Without departing from the spirit and scope of the invention, therefore, the appended claims cover all such changes and modifications that are within the scope of the present invention.
AUXILIARY ODOR CONTROL AGENTS OPTIONALThe articles of the present invention may optionally contain an effective amount, i.e. odor control, of an auxiliary odor control agent, preferably of about 0.01 gr. to approximately 15 gr. per article, more preferably approximately 0.1 gr. to approximately 10.0 gr. per item, the odor control agent selected from the group consisting of: a. zeolite; b. activated carbon; c. Silica gel; d. encapsulated perfume, activated with moisture; and. cyclodextrin; F. activated alumina; and g. mixtures thereof.
ZEOLITES In general terms, traditional zeolites comprise an aluminate / silicate system, with associated actiones, M, which provide a total electrical neutrality.
Empirically, the zeolite system can be represented as xA102. and Si02 and the electrically neutral zeolite as x / n M. x A102. ySi02. zH20 where: x and y are each integer, M is a cation and n is the charge on the cation. As denoted by the empirical formula, the zeolites may also comprise waters of hydration (zH20),M can be a wide variety of cations, for example Na +,K +, NH 4 +, alkylammonium, and the like. A preferred class of zeolites useful as the auxiliary odor control agent are characterized as "intermediate" aluminate / silicate zeolites. The "intermediate" zeolites are characterized by molar ratios of SiO2 / A102 of less than about 10. Typically, the molar ratio of SiO2 / A102 will vary from about 2 to about 10. The intermediate zeolites are described in U.S. Patents Numbers 4,795,482 and 4,826,497, which are incorporated herein by reference. The intermediate zeolites have a large surface area (approximately 700-800 m / g) against high zeolites (approximately 400 m2 / g). Therefore, lower intermediate zeolites may be necessary to absorb a given amount of odor, etc., in a weight-based weight. Also, intermediate zeolites are more tolerant to moisture and retain greater absorption capacity in the presence of water. A wide variety of intermediate zeolites suitable for use herein are commercially available as series VALFOR CP301-68, VALFOR 300-63, VALFOR CP300-35,VALFOR CP300-56, and CBV 400 to CBV 760, all from PQ Corporation. The zeolites used herein are not of the fibrous type, for example, several Mordenites, and some types of Y zeolites, since these may be subject to safety judgments. Accordingly, the term "zeolite" as used herein is intended to encompass only non-fibrous zeolites, although some naturally occurring zeolites satisfy the objectives of the present invention, synthetic zeolites including zeolite type A (SiO2 / Al203 = 1.4 to 2.4), the zeolite of type X (Si02 / Al203 = 2 to 3), and the zeolite of type Y (Si02 / Al203 = 3 to 6). The preferred zeolites are synthetic Y-type zeolites. Although intermediate zeolites are preferred, higher zeolites may be employed as odor control auxiliaries in the practice of the present invention, alone or in combination with intermediate-ratio zeolites. The higher zeolites include, for example, the well-known "molecular sieve" zeolites of the ZSM, the zeolite beta, etc., type (generally in the scale of particle size from 1 to 10 microns) and the zeolite materials sold under the ABSCENTS trademarks by Union Carbide Corporation and UOP. ABSCENTS are typically available as a white powder on the 3 to 5 micron particle size scale (See: ABSCENTS, A New Approach for Odor Control by A. J. Gioffre, Copyright 1988 by the Union Carbide Corporation). Various other modified zeolite-type materials that can be used in the present invention, such as the silicone aluminum phosphorus-manganese oxide molecular sieves and other zeolite-based odor control compositions are described in US Pat. 4,793,833, Lok et al .; 4,604,110; 4,437,429; and 4,648,977, which are incorporated herein by reference.
CARBON AGENTS THAT CONTROL THE SMELL The carbon material used in the present invention is the material well known in commercial practice as an adsorber for organic molecules and / or for air purification purposes. Suitable carbon to be used here is available from a variety of commercial sources under the trade names such as CALGON type "CPG", type "PCB", type "SGL", type "CAL", and type "OL". Frequently, said carbon material is referred to simply as "activated" carbon or "activated" vegetable or animal charcoal. It should be understood that any of the "air-purifying" or "activated" carbons of the trade can be used in the practice of the present invention. If the zeolites here are optionally used in conjunction with the activated carbon, it is preferred (for aesthetic reasons) to coat the carbon with the zeolite using a binder.
PERFUME ENCAPSULATED. ACTIVATED WITH HUMIDITY The compositions and articles of this invention optionally contain an effective amount of various encapsulated perfume particles, activated by moisture. Such materials include, for example, complexes including cyclodextrin / perfume, perfume microcapsules of cellular matrix of polysaccharides, and the like. Perfume encapsulation minimizes the interaction with, and / or depletion by, odor absorbing materials before using the product.
The perfume is released when the materials are moistened, to provide a pleasant odor signal when used. In particular, cyclodextrin inclusion complexes of volatile perfumes, with particle sizes of less than about 12 microns, are preferred, U.S. Patent Application Serial No. 07 / 707,266, Trinh et al., Filed on 6 March 1990, from page 13, line 16, to page 14, line 33, which is incorporated herein by reference, describes the cyclodextrin / perfume inclusion complex information. A description of the appropriate particle size of the cyclodextrin / perfume complex is also disclosed in U.S. Patent Application Serial No. 07 / 707,266, page 14, line 34, to page 16, line 12, which is also incorporated in the present by reference. It is essential that at least one effective amount of the cyclodextrin / perfume complex be applied to the article.
Effective amounts are typically on the scale of about 0.005 gr. to approximately 10 gr. , preferably of approximately 0.01 gr. to about 3 g., more preferably about 0.02 g. to approximately 1 gr. by article.
PERFUME The perfumes that may optionally be incorporated into the articles of the present invention are the conventional perfumes known in the art. The selection of any perfume component, or amount of perfume, is based on functional and aesthetic considerations. The preferred perfume components useful in the present invention are highly volatile and moderately volatile perfume ingredients, most preferably the highly volatile, low boiling perfumes. The highly volatile, low boiling perfume ingredients typically have boiling points of about 250 ° C or lower. These highly volatile perfumes are fleeting and are quickly lost as they are released. Many of the most moderately volatile perfume ingredients are also quickly lost. Moderately volatile perfume ingredients are those having their boiling points of from about 250 ° C to about 300 ° C. Many of the perfume ingredients along with their odor character, and their physical and chemical properties, such as boiling point and molecular weight, are given in "Perfume and Flavor Chemicals (Aroma Chemicals)," Steffen Arctander, published by the author , 1969, incorporated herein by reference. Examples of moderately volatile perfume ingredients and highly volatile, low boiling perfume ingredients are disclosed in U.S. Patent Application Serial No. 07 / 707,266, Trinh et al., Filed March 6, 1990. , page 8, line 13, to page 9, line 4, which is incorporated herein by reference.
MATRIX PERFUME MICROCAPSULES The water-soluble cell matrix perfume microcapsules are solid particles that contain perfume stably maintained in the cells. The water-soluble matrix material comprises mainly polysaccharide and polyhydroxy compounds. The polysaccharides are preferably higher polysaccharides of the non-swelling types, soluble in colides, such as natural gums, for example, gum arabic, starch derivatives, hydrolyzed and dextrinized starches, and the like. The polyhydro compounds are preferably alcohols, vegetable-type sugars, lactones, monoethers and acetals. Cellular matrix microcapsules useful in the present invention are prepared by, for example, (1) forming an aqueous phase of the polysaccharide or polyhydroxy compound in appropriate proportions, with the addition of emulsifier if necessary or desirable; (2) emulsifying the perfumes in the aqueous phase; and (3) removing moisture while the mass is plastic or flowable, for example, by drying the droplets of the emulsion by spray. The matrix materials and process details are described in, for example, U.S. Patent No. 3,971,852, Brenner et al., Issued July 27, 1976, which is incorporated herein by reference. The present invention preferably has minimal non-encapsulated super-solid perfume, preferably less than about 1%. Perfume microcapsules, activated by moisture, can be obtained commercially, for example, as IN-CAPR from Polak's Fruit Works, Inc., Middletown, New York; and as Optilok System® encapsulated perfumes from Encapsulated Technology, Inc., Nyack, New York. The water-soluble matrix perfume microcapsules preferably have a size of from about 0.5 microns to about 300 microns, more preferably from about 1 micron to about 200 microns, most preferably from about 2 microns to about 100 microns. It is essential that at least one effective amount of the water-soluble matrix perfume microcapsules be applied to the article. Effective amounts are typically in the range of from about 0.001 gr. to about 5 g., preferably about 0.005 g. to approximately 1 gr. , more preferably of about 0.01 gr. to approximately 0.5 gr., per article.
INCORPORATION OF ENCAPSULATED PERFUME IN ABSORBING ITEMSCyclodextrin / perfume complexes of small particle sizes can be applied to the fluid absorbent articles by uniformly spraying, mixing or distributing the cyclodextrin / perfume complex powder over the fluid absorbing materials. Although, it is commonly known that when in use, the body fluid is not normally distributed to the entire fluid absorbent article, for example, sanitary napkin, but is usually located in a portion of the article. Similarly, it is not necessary to apply the cyclodextrin / perfume complex powder to the entire fluid absorbent article. Preferably, the powder of the cyclodextrin / perfume complex is applied to areas very likely to be wetted by body fluids to avoid waste in areas where bodily fluids are not normally received. In addition, when distributed as a dry powder, the cyclodextrin / perfume complex particles can deviate away from the preferred locations, and move toward areas where they have less opportunity to be solubilized by body fluids, and become less effective. The deviation happens either during the manufacturing process, for example, bending and packing the items, and as during subsequent steps, for example, transportation, and unfolding and redoubling of the absorbent articles of fluids in use. Therefore, it is preferred to provide a means to immobilize the cyclodextrin / perfume complex powder over the preferred locations in the fluid absorbent articles. The immobilization can be effected by a variety of methods, i.e. hot melt adhesives, thermoplastic binder fibers, thermoplastic binder particles, or other methods known to those skilled in the art. A preferred method is to use a water soluble binder to bind the powder of the cyclodextrin / perfume complex to the fluid absorbent core and / or the top sheets. The water-soluble binders are preferably polymeric. These may be low melting point polymers such as polyethylene glycols (PEG), poly (ethylene glycol) methyl ethers, or mixtures thereof. Preferred water-soluble, low-melting PEG materials have the general formula RO- (CH2-CH20) nR, wherein each R is a hydrogen radical, an alkyl radical of C, -C4, or mixtures of said radicals, and has an average molecular weight(MW) of from about 600 to about 20,000 (n is from about 13 to about 450). More preferred PEG materials are polyethylene glycols, poly (ethylene glycol) methyl ethers, or mixtures thereof, with MW of from about 1,000 to about 9,000 (n of about 20 to about 200), more preferably of about 1,400 to about 4,500 (n of about 30 to about 100). The weight ratio of the cyclodextrin / perfume complex to the PEG material is from about 3: 1 to about 1: 5, preferably from about 2: 1 to about 1: 3. A preferred process for binding the cyclodextrin / perfume complex powder involves mixing the powder of the cyclodextrin / perfume complex, of small particle size, with a hydrophilic, melted PEG material. The molten mixture can be sprayed directly to the dry, fluid absorbent materials, or to the top sheets, then allowing the droplets to solidify on said nonwoven top sheets or materials. Another preferred method is to spray the solidified binder / cyclodextrin-perfume complex into first small particles. Said particles can then be bound and immobilized on the surface of the absorbent materials or on the non-woven upper sheets, distributing the particles on said surface, melting said particles by, for example, a heat source, and then resolidifying to agglutinate said particles to said surface. In the weight ratio of the cyclodextrin / pefume complex to the PEG material of from about 3: 1 to about 1: 3, the molten mixture can be solidified at room temperature, then sprayed at room temperature or cryogenically. In the weight ratio of the cyclodextrin / pefume complex to the PEG material of from about 1: 2 to about 1: 5, the molten mixture can be dried by, for example spray drying, maruating, etc., into solid prills. The particles of the solid mixture of the PEG / cyclodextrin / perfume complex material preferably have sizes of from about 10 microns to about 1,000 microns, more preferably from about 20 to about 600 microns. Another preferred method is to apply the suspension of the cyclodextrin / perfume complex to the fluid absorbent material and / or to the nonwoven topsheet. Upon drying, the small particles of the cyclodextrin complex adhere to the absorbent material and are immobilized on said material. This can be done, for example, by spraying the suspension of the cyclodextrin / perfume complex onto the absorbent fiber web, dried, and already formed, It is also preferred to incorporate a water soluble polymer, such as PEG, polyvinyl alcohols, acids polyacrylics, and polyvinylpyrrolidone in the aqueous suspension of the cyclodextrin / perfume complex, after it has been formed.The aqueous mixture is distributed, for example, by spraying to the fluid absorbent materials or to the non-woven upper sheets, then the resulting combination is dried , and therefore the cyclodextrin is bound to said fluid absorbent materials or to higher sheets, the MW of said polymers being from about 1,000 to about 200,000.; more preferred is from about 2,000 to about 100,000.
CICLODEXTRIN As used herein, the term "cyclodextrin" (non-complex) includes any type of known cyclodextrins such as unsubstituted cyclodextrins containing from six to twelve glucose units, especially, alpha-, beta-, and gamma-cyclodextrins, and / or its derivatives, and / or their mixtures. A more complete description of non-complex cyclodextrins that may optionally be used in articles of the present invention are described in U.S. Patent Application Serial Number 07 / 707,266, Trinh et al., Supra, page 4, line 12, a page 5, line 26, which is incorporated here by refererence. All percentages, relationships, and parts here, in the description, examples and claims, are by weight and approximations unless otherwise stated. The following are non-limiting examples of the present invention.
EXAMPLE 1A three-dimensional, perforated polymeric web of this invention is made using the process described in U.S. Patent No. 4,839,216, Curro et al., Issued June 13, 1989, which is incorporated herein by reference. A non-perforated poly (ethylene) film web11 (1% LDPE Bactekiller AZ®, available from Kanebo USA containing about 1% zeolite impregnated with a heavy metal ion) is fed into the forming structure at a rate of approximately 109.26 meters per minute and subjected to a high pressure water jet. The forming structure uses a surface that has a pattern of formed openings. This particular surface has a repeating geometrical pattern of non-equilateral pitting pentagon holes 97 of approximately 0.0889 cm. in size with the width of the metal between the holes of approximately 0.01778 cm. The flow of water from the spray nozzles is equally spaced at about 3,175 cm apart and centered through the film web. Spray nozzles are of the 2540 water jets type available from Spraying System Co., Wheaton, III. These provide a spray even at the angle of approximately 25 degrees. The water is supplied to the nozzles at a temperature of approximately 99 ° C and at a pressure of approximately 1150 psig. The nozzles are positioned in such a way that the spray angle is approximately 25 degrees parallel to and centered in the transverse direction of the machine. The resulting perforated top sheet is dried from the water residues by drying with an absorbent medium or by hot air drying on or through the sheet.
EXAMPLE 2A gauze placed in wet, with three folds, containing approximately 5 gr. of absorbent gelation material per square foot (which produces approximately 0.68 g of absorbent gelation material per sanitary pad pad in a folded size of 20cm x 7cm) is used as the core. An additional piece of gauze is placed on top of the core as a secondary top sheet. The prepared absorbent structure is placed on the top of a slightly large piece of the polyethylene backsheet, with the piece of gauze exposed on top. A top sheet of formed film of the type described in Example 1 is uniformly coated on its underside with approximately 0.03 g of a latex adhesive, and the excess adhesive is cleaned. The top sheet is rolled with a glass rod to ensure good contact and proper application of the adhesive. The top sheet is then placed on top of a previously prepared core assembly. To ensure a good union of the upper sheet to the core, weigh the upper sheet with a piece of Plexiglas. It is jointly sealed on the edges with a hot plate using a metal mold of the desired shape joining and heated by the plate. The total product consists of; Bactekiller® containing upper sheet / gauze / absorbent core / back sheet. Optional, adhesive can be applied on the outer side of the back sheet of the pad to fix the article to the undergarments. The top sheet of the product is sprayed with approximately 0.03 gr. of non-ionic surfactant Pegosperse 200ML (PEG 200) to hydrophilize the fluid receiving surface of the upper sheet. Although the foregoing illustrate the preparation of a sanitary napkin in the manner of the present invention, a completely similar operation can be employed to prepare a panty liner (generally of the approximate dimensions of 14cm x 5cm) with appropriate modifications of the amount of the sanitary napkins. ingredients, as noted here above.
EXAMPLE 3 A gauze placed in wet, three-fold, containing about 5 gr. of absorbent gelation material per square foot (which produces approximately 0.68 g of absorbent gelation material per sanitary pad pad in a folded size of 20cm x 7cm) is used as the core. The three-fold gauze laminate is sprayed with a fine mist of water and opened to expose the absorbent gelation material. Approximately 0.5 gr. of Valfor CP300-56 zeolite is spread on the absorbent gelation material. The two sides of the gauze are folded back to their original positions, thereby sealing the absorbent gelation material and the zeolite inside. The still wet core is resealed using a hot iron, pressing firmly. Approximately 0.2 gr. of the cyclodextrin / perfume poly (ethylene glycol) complex [PEG] is spread over the dry core, with a high concentration in the central area of the core surface. An additional piece of gas is placed on top of the core as a secondary top sheet. The hot plate is pressed on top of the gauze to melt the PEG of the cyclodextrin / perfume complex such that upon cooling the complex particles are immobilized on the surface of the core and the gauze. An absorbent core prepared in the above manner is placed on the top of a slightly large piece of the polyethylene backsheet, with the piece of gauze exposed on top. A top sheet of formed film of the type described in Example 1, is uniformly coated on its underside with approximately 0.03 g of a latex adhesive, and the excess adhesive is cleaned. The top sheet is rolled with a glass rod to ensure good contact and proper application of the adhesive. The top sheet is then placed on top of a previously prepared core assembly. To ensure a good union of the upper sheet to the core, weigh the upper sheet with a piece of Plexiglas. It is jointly sealed on the edges with a hot plate using a metal mold of the desired shape joining and heated by the plate. The total product consists of; Bactekiller® containing the top sheet / gauze / cyclodextrin complex / absorbent core with zeolite / backsheet. Optionally, adhesive may be applied to the outer side of the backsheet of the pad to secure the article to the undergarments. The top sheet of the product is sprayed with approximately 0.03 gr. of non-ionic surfactant Pegosperse 200ML (PEG 200) to hydrophilize the fluid receiving surface of the upper sheet. Although the foregoing illustrate the preparation of a sanitary napkin in the manner of the present invention, a completely similar operation can be employed to prepare a panty liner (generally of the approximate dimensions of 14cm x 5cm) with appropriate modifications of the amount of the sanitary napkins. ingredients, as noted here above.