MXPA01000568A

MXPA01000568A - Absorbent article having a reduced viability of candida albicans

Info

Publication number: MXPA01000568A
Application number: MXPA/A/2001/000568A
Authority: MX
Inventors: Susan Carol Paul; Michael John Faulks; Frank Jerrel Akin; Pamela Jean Mayberry; Audra Stefanik Wright
Original assignee: KimberlyClark Worldwide Incorporated
Priority date: 1998-08-25
Filing date: 2001-01-16
Publication date: 2001-09-07

Abstract

An absorbent article includes a vapor permeable backsheet, a liquid permeable topsheet positioned in facing relation with the backsheet;and an absorbent body located between the backsheet and the topsheet which defines multiple zones of high air permeability. The absorbent article may also include a ventilation layer between the absorbent body and the backsheet and a surge management layer between the absorbent body and the topsheet. The article exhibits improved air exchange within the article during use. As a result, the article exhibits substantially reduced levels of hydration of the wearer's skin when in use which renders the skin less susceptible to the viability of microorganisms.

Description

ABSORBENT ARTICLE THAT HAS A REDUCED FEASIBILITY OF CANDIDA ALBICANS Background of the Invention Field of the Invention The present invention relates to an absorbent article for absorbing body fluids and exudates, such as urine. More particularly, the present invention relates to absorbent garments, such as disposable diapers and adult incontinence garments, which are configured to absorb exudates from the body while also helping to provide reduced skin hydration.

Description of Related Art Many known diaper configurations employ absorbent materials located between a liquid-permeable upper sheet and a lower sheet impervious to liquid vapor. Such lower sheets are well suited to prevent the migration of liquid waste from absorbent materials to a user's outer garments. Unfortunately, the use of liquid and vapor impermeable bottom sheets can result in a high degree of wetness inside the diaper when worn which results in relatively high skin hydration levels. Interior diapers with moisture environment and occlusives incorporating such inferior leaves can promote the viability of microorganism including Candida albicans, which can lead undesirably to the onset of diaper rash (diaper rash).

Diaper dermatitis can afflict almost every infant at some point during the years of diaper use. The most severe form of this condition is usually caused by secondary infection with the fungus Candida albicans. Even though other factors may influence the pathogenesis of these fungi, a critical factor is the relative humidity within the diaper which is directly related to the occlusion or semiocclusion of the diaper area.

In order to reduce the moisture level within the diapers, the breathable polymer films have used as outer covers for the absorbent articles, such as disposable diapers. Breathing films are typically constructed with micropores to provide desired levels of liquid impermeability and air permeability. Other disposable cloth designs have been arranged to provide regions with capacity in the form of panels capable of breathing perforated regions in otherwise vapor-impermeable lower sheets to help ventilate the garment.

Conventional absorbent articles, such as those described above, have not been completely satisfactory. For example, articles which employ perforated films or breathable panels may exhibit excessive drainage of the liquids from the article and may excessively soil the outer clothing of the user in the regions of the perforations or panels. In addition, when the absorbent material of the article is loaded with liquid, the wet absorbent can block the moisture escaping from the wearer's skin. Such absorbent press designs have not been able to maintain a high level of ability to breathe when wetted to sufficiently reduce the hydration of the wearer's skin. As a result of this, the user's skin has remained susceptible to rash, abrasion and irritation.

Synthesis of the Invention In response to the difficulties and problems discussed above, a new and disposable absorbent article has been discovered which has a higher air exchange rate when wetted, at reduced levels of skin hydration and reduced viability of microorganisms.

As used herein, the reference to "air exchange" refers to the transfer of air from the inside of a diaper, when in use on a user, to the exterior of the diaper (ambient atmosphere).

As used herein, an essential liquid impervious material is constructed to provide a head of at least about 60 cm / centimeter desirably of at least about 80 centimeters more desirably of at least about 1 centimeter. A suitable technique for determining the hydro head value is the Hydrostatic Pressure Test which is described in more detail below.

As used herein, an essentially vapor permeable material is constructed to provide a water vapor transmission rate (WVTR) of at least about 100 g / square meter / 24 hours, desirably at least about 250 g / square meter / 24 hours, and more desirably of at least about 500 g / square meter / 24 hours. A suitable technique for determining the water vapor transmission rate is the Water Vapor Transmission Rate Test which is described in detail in May below.

In one aspect, the present invention relates to an absorbent article which comprises an absorbent, a front waist section, a rear waist section, an intermediate section which interconnects the front and back waist sections. The absorbent article defines a Humidity Exchange Rate of at least about 190 cubic centimeters per minute calculated according to the Gas Tracker Test as set forth herein. In a particular embodiment, the article defines a Wet Air Exchange Rate of at least about 200 desirably of at least about 225 and more desirably of at least about 250 cubic centimeter per minute calculated in accordance to the Ga Tracker Test. The absorbent article may also define a Dry Air Exchange Rate of at least about 52 cubic centimeters per minute calculated according to the Gas Tracker Test and / or a Skin Hydration Value of less than about 18 grams per square meter per hour calculated according to the Skin Hydration Test as stated here.

In another aspect, the present invention relates to a disposable absorbent article which comprises an absorbent, a front waist section, a back waist section, and an intermediate section which interconnects the front and rear waist sections. The absorbent article defines a Skin Hydration Value of less than about 18 grams per square meter per hour calculated according to the Skin Hydration Test set forth herein. In a particular embodiment, the absorbent article may define a hydration value. of the skin of less than about 15, desirably less than about 12 and more desirably less than about 10 grams per square meter per ho calculated according to the Skin Hydration Test. The absorbent article may also define a Humidity Air Exchange Rate of at least about 190 cubic centimeter per minute and / or Dry Air Exchange Rate of at least about 525 cubic centimeters per minut calculated according to The Starter Gas Test as set forth here.

In another aspect, the present invention relates to a disposable absorbent article which defines a front waist section, a rear waist section and an intermediate section which interconnects the front and back waist sections. The absorbent article includes a) a vapor permeable lower sheet which defines a Water Vapor Transmission rate of at least about 1,000 grams per square meter per 24 hours calculated according to the Water Vapor Transmission Test. as established here; b) an upper leaf permeable to the liquid which is placed in a frontal relation with the lower leaf; and c) an absorbent body located between the upper sheet and the lower sheet wherein the cua defines multiple zones of superior air permeability for or improved air exchange. In a particular embodiment the high air permeability zones in the body absorb a defined Frazier Porosity which is at least about 10 percent greater than a Frazier Porosity absorbing body parts adjacent to the air permeability zones. The absorbent article may also include a ventilation layer located between the topsheet and the absorbent body.

In yet another embodiment, the present invention relates to a disposable absorbent article which defines a front waist section, a rear waist section, an intermediate section which interconnects the front and back waist sections. The absorbent article includes a lower sheet impervious to liquid, vapor permeable which defines a Water Vapor Transmission Rate of at least about 1,000 grams per square meter per 2 hours calculated according to the Transmission Test of Steam of Water as stated here; b) a liquid permeable upper sheet which is placed in a frontal relation with the lower leaf; c) an absorbent body located between the lower blade and the upper blade; d) a ventilation layer located between the lower sheet and the absorbent body; and e an emergence management layer located between the upper blade and the absorbent body. In a particular embodiment, the absorbent body of the absorbent article includes a plurality of zones of high air permeability for improved air exchange which define a Porosida Frazier which is at least about 10 per cent greater than a Frazier porosity of absorbent body parts adjacent to the zones.

In yet another aspect, the present invention relates to a disposable absorbent article which includes an absorbent, a front waist section, a back waist section and an intermediate section which interconnects the front and back waist sections. The absorbent article defines a viability of Candida albicans which is less than about 85 percent of the viability of Candida albicans of a control calculated according to a Viability Test of Candida albicans as set forth herein. In a particular embodiment, the viability of Candida albicans is less than about 80 percent and desirably less than about 60 percent of the viability of Candida albicans of the control calculated according to the Feasibility Test of Candida albicans. The absorbent article may also define a Wet Air Exchange Rate of at least d about 190 cubic centimeters per minute and / or a Dry Air Exchange Rate of at least about 52 cubic centimeters per minute calculated in accordance to the Gas Tracker Test as set forth herein, and / or a Skin Hydration Value of less than about 18 grams per square meter per hour calculated according to the Skin Hydration Test as set forth herein.

The present invention advantageously provides improved absorbent articles which exhibit substantially reduced levels of skin hydration of the wearer when in use compared to conventional absorbent articles. The reduced level of Foot Hydration promotes a more comfortable and drier skin and makes the skin less susceptible to the viability of microorganisms. Therefore, the user of the absorbent articles made according to the present invention has a reduced Skin Hydration which can lead to a reduction in the incidence of irritation and skin rash.

Brief Description of the Drawings The invention will be more fully understood and the additional advantages will become apparent when reference is made to the following detailed description of the invention and to the accompanying drawings, in which: Figure 1 representatively shows a top plan partially cut away from an absorbent article according to an embodiment of the invention.

Fig. 2 representatively shows a section view of the absorbent article of Fig. 1 taken along line 2-2.

Fig. 3 representatively shows a top plan view partly in section of an absorbent body for an absorbent article according to another embodiment of the invention; Figure 4 representatively shows a section view of the absorbent body of Figure 3 taken along line 4-4.

Figure 5 representatively shows a top plan view partially in section of an absorbent body for an absorbent article according to another embodiment of the invention; Y Figure 6 representatively shows a sectional view of the absorbent body of Figure 5 taken along line 6-6.

Detailed description of the invention The following detailed description will be in the context of a disposable diaper article which is adapted for use by infants around the lower torso. It is readily apparent, however, that the absorbent article of the present invention will also be suitable for use with other types of absorbent article, such as pads for women's care, garments for incontinence, underpants, and the like.

The absorbent articles of the present invention advantageously exhibit an essentially reduced level of hydration of the user's skin in use when compared to conventional absorbent articles. Therefore, the user of the absorbent articles of the different aspects of the present invention has a reduced foot hydration which makes the skin less susceptible to the viability of microorganisms which can lead to a reduction in the incidence of hydration and skin rash It has been found that the ability of the absorbent articles of the present invention to exhibit a low level of hydration on the user's skin during use depends, at least in part, on the ability of the absorbent article to achieve a high exchange rate. of air inside the article. In addition, it has been discovered that the achievement of such low levels of skin hydration also depends on the ability of the absorbent article to maintain the high rate of air exchange even when wet.

The capacity of an absorbent article to achieve superior air exchange rate both when it is wet and when it is wet, has been qualified, for the purpose of this application, as the Dry Air Exchange Rate, l Air Exchange Rate Wet and the Rate Ratio Wet Air Exchange / Dry Air Exchange Rate was determined according to the Gas Tracker Test as set forth below. Briefly, the Gas Tracked Test involves injecting a tracking gas at a constant rate into the absorbent article near the user's skin while the article is being used. Simultaneously, the concentration of the tracer gas in the air space between the article and the user is measured by removing a sample at the same constant rate as the injection. The exchange of air is then determined based on mass balances of the tracker and the air within the space in question.

To achieve the desired low levels of hydration of the skin, the absorbent articles of the different aspects of the present invention can be constructed to define a wet air exchange rate of at least about 190 cubic centimeters per minute, generally from at least about 200 cubic centimeters per minute, desirably from at least about 225 cubic centimeters per minute, more desirably from at least about 250 cubic centimeters per minute and even more desirably from at least about 300 cubic centimeters per minute. 300 cubic centimeters per minute. For example, absorbent articles can define a Wet Air Interchange Rate of from about 175 to about 150 cubic centimeters per minute and desirably from about 225 to about 1500 cubic centimeters per minute. Absorbent articles which exhibit lower rates of wet air exchange than those mentioned above allow a sufficient amount of air exchange undesirably result in increased levels of skin hydration. Such increased levels of hydration of the foot can make the skin more susceptible to the viability of microorganisms which can undesirably lead to an increase in the incidence of skin irritation and rash.

The absorbent articles of the different aspects of the present invention may also be constructed to define a Dry Air Exchange Rate of at least about 525 cubic centimeters per minute, generally at least about 575 cubic centimeters per minute. , desirably of at least about 62 cubic centimeters per minute, more desirably of at least about 675 cubic centimeters per minute, and even more desirably of at least about 750 cubic centimeters per minute for improved performance . For example, absorbent articles can define a Dry Air Exchange Rate of from about 525 to about 250 cubic centimeters per minute, and desirably from about 575 to about 2500 cubic centimeters per minute. Absorbent articles which exhibit Dry Air Exchange Rates lower than those mentioned above do not allow a sufficient amount of air exchange and undesirably result in increased levels of skin hydration. Such increased levels of hydration of the foot can make the skin more susceptible to the growth of microorganisms which undesirably leads to an increase in the incidence of skin irritation and rash.

The absorbent articles of the different aspects of the present invention can further be constructed to define a ratio of Wet Air Exchange Rate / Dry Air Exchange Rate of at least about 0.20, generally at least about 0.23, desirably of at least about 0.27, and more desirably of at least about 0.30 for improved performance. For example, the absorbent articles may define a ratio of Wet Air Exchange Rate / Dry Air Exchange Rate of from about 0.20 to about 1 and desirably from about 0.23 to about 1 for a improved performance.

The ability of the absorbent articles of the present invention to exhibit higher levels of air exchange rate both when they are dry and when wet to reduced levels of skin hydration The ability of an absorbent article to achieve a low level of Hydration of the skin, has been qualified for the purpose of this application as the Skin Hydration Value. Com used here, "Skin Hydration Value" refers to the value determined according to the Skin Hydration Test as set forth below. In general, the Hydration Value of the Skin is determined by measuring the loss of evaporative water on the skin of the test subjects after use of the wet absorbent article for a set period of time. In particular embodiments the absorbent articles of the various aspects of the present invention can be constructed to define a Skin Hydration Value of less than about 18 grams per square meter per hour, generally less than about 1 grams per square meter per hour, generally less than about 15 grams per square meter per hour, desirably less than about 12 grams per square meter per hour more desirably less than about 10 grams per square meter per hour, even more desirably less about 8 grams per square meter per hour, and even more desirably less than about 5 grams per square meter per hour for improved performance. For example, the absorbent articles of the present invention can define a skin hydration value of from about 0.1 to about 18 grams per square meter for now, and desirably from about 0.1 to about 12. grams per square meter per hour. In the absorbent articles which exhibit the Skin Hydration Values greater than that mentioned above can make the skin more susceptible to the growth of microorganisms which can undesirably lead to an increase in the incidence of skin rash irritation.

The absorbent articles of the present invention can also exhibit reduced viability rates of microorganisms which can lead to a reduction in skin irritation. It has been hypothesized that the reduced viability of the microorganisms is a direct result of the increased ability to breathe and exchange air within the articles of the present invention. The capacity of an absorbent article to achieve a low rate of viability of microorganisms, has been qualified for the purposes of this application, such as the viability value of Candida albicans, since the hypothesis has been made that the presence of Candida albicans is relate directly to the incidence of irritation and, in particular, to the rash. As used herein, the term "viability of Candida albicans" refers to the value determined according to the Candida albicans Viability Test set forth below. The Candida albicans Viability Test, in general, is a comparison of the viability of Candida albicans under a parch of the test absorbent article to the Candid albicans viability under a control patch from a conventional absorbent article having an outer cover without capacity to breathe, for example, an outer cover having a Water Steam Transmission Rate less than 100 grams per square meter per 24 hours.

In particular embodiments, the absorbent articles of the various aspects of the present invention can be constructed to define a viability of Candid albicans of less than about 85 percent, generally d less than about 80 percent, desirably less than about of 60 percent, more desirably less than about 40 percent, and even more desirably less than about 20 percent of the viability of Candida albicans from control for improved performance. For example, the absorbent articles of the present invention can define a viability of Candida albicans of less than about 2.5, desirably less than about 2.0, and more desirably less than about 1.75 log units. Colony formers of Candida albicans when inoculated with a suspension of about 5-7 log colony forming units of Candida albicans according to the Feasibility Test of Candida albicans. Absorbent articles which exhibit higher viability values of Candida albicans than those mentioned above may undesirably lead to an increase in the incidence of skin irritation and skin rash. Desirably, the viability values of Candida albicans are obtained in the incorporation of antimicrobial agents. of absorbent articles which can be perceived by consumers in a negative way.

It has been found that the improved and acceptable performance of the absorbent articles can be achieved by selecting the constructions having a combination of one or more of the properties described above. For example, a given level of acceptable improved performance can be achieved by employing an absorbent article which exhibits a dry air exchange rate of at least about 525 cubic centimeters per minute and a Wet Air Exchange Rate of about 525 cubic centimeters per minute. at least about 175 cubic centimeters per minute, and desirably a Dry Air Exchange Rate of at least about 675 cubic centimeters per minute and a Humid Air Exchange Rate of at least about 200 centimeters cubic per minute. Alternatively, improved performance can be achieved by employing an absorbent article which exhibits a Wet Air Exchange Rate of at least about 175 cubic centimeters per minute and a Skin Hydration Value of less than about 18 grams. per square meter per hour, and desirably a Wet Air Exchange Rate of at least about 200 cubic centimeter per minute and a Skin Weight Hydrating Value of about 12 grams per square meter per hour.

Furthermore, it has been found that improved performance can be achieved by employing article absorbers having a Dry Air Exchange Rate of at least about 525 cubic centimeters per minute and a Wet Air Exchange Rate ratio. Exchange of Dry Air of at least about 0.20 d and desirably a Dry Air Exchange Rate of at least about 625 cubic centimeters per minute, a Wet Air Exchange Rate / Swap Rate ratio of dry air of at least about 0.23.

Examples of suitable constructions of absorbent articles for use in the present invention are described below and are representatively illustrated in Figures 1-16. Fig. 1 is a representative plan view of an integral absorbent garment article, such as a disposable wipe 10 of the present invention in its n constrained and flat state (e.g., with all the elastic contraction induced shrinkage removed). Parts of the structure are partially cut to more clearly show the interior construction of the diaper 10, and the diaper surface which contacts the wearer is facing what it observes. Fig. 2 representatively shows a section view of the absorbent article of Fig. 1 taken along line 2-2. With reference to Figures 1 and 2, the disposable diaper 10 generally defines a front belt section 12, a rear waist section 14, and an intermediate section 16 which interconnects the front and back belt sections. The posterior front waist sections include the general parts of the article which are constructed to extend essentially over the front and back abdominal regions of the user respectively, during use. The middle section of article includes the general part of the article which is constructed to extend through the crotch region of the wearer between the legs.

The absorbent article includes a vapor permeable lower sheet 20, a liquid-permeable upper sheet 2 positioned in a front relation with the lower sheet 20, and an absorbent body 24, such as an absorbent pad, which is located between the lower sheet 20 and the upper sheet 22. The lower sheet 20 defines a length and a width which, in the illustrated embodiment, coincide with the length and width of the diaper 10. The absorbent body 20 generally defines a length and a width which are less than the length and width of the lower sheet 20, respectively. Thus, the marginal portions of the diaper 10, such as the marginal sections of the lower sheet 20, may extend beyond the end edges of the absorbent body 34. In the illustrated embodiments, the lower sheet 20 extends outwardly beyond the ends. terminal marginal edges of the absorbent body 24 to form the side margins and end margins of the diaper 10. The topsheet 22 is generally coextensive with the bottom sheet 20 but may optionally cover an area which is larger or smaller than the area of l lower sheet 20 as desired. The lower sheet 20 and the upper sheet 22 are intended to face the garment and the wearer's body, respectively, while in use.

The permeability of the lower sheet is configured to increase the breathability of the absorbent article to reduce the hydration of the user's skin during use without allowing excessive condensation of vapor, such as from urine, on the surface facing the garment. of the lower sheet 20 which can undesirably wet the wearer's or user's clothes.

To provide an improved notch and to help reduce runoff of body exudates from diaper 10, the diaper side margins and end margins can be stretched with suitable elastic members, such as single or multiple strands of elastic. The elastic threads may be composed of synthetic natural rubber and may optionally be shrinkable with heat-elasticized heat. For example, as representatively illustrated in Figures 1 and 2, the diaper 10 may include the leg elastics 26 which are constructed to operably collect and purse the diaper side margins 10 to provide the elasticized leg bands which may be notched. closely around the user's legs to reduce runoff and provide improved comfort and appearance. Similarly, the waist elastics 28 can be used to elasticize the end margins of the diaper 10 to provide the elastic waistbands. The waist elastics are configured to gather the waist sections operably to provide a comfortably close and elastic fit around the waist. waist of the user. In the illustrated embodiments, the elastic members are illustrated in their stretched and n contracted condition for the purposes of clarity.

The attachment means, such as the hook and loop fasteners 30, are employed to secure the diaper to a wearer. Alternatively, other fastening means, such as buttons, pins, snaps, adhesive tape fasteners, cohesives, mushroom and curl fasteners, or the like, may be employed.

The diaper 10 can further include other layers of the absorbent body 24 and the topsheet 22 or the bottom sheet • 20. For example, as representatively illustrated in Figures 1 and 2, the diaper 10 may include a vent layer 32 located between the absorbent body 24 and the lower sheet 2 to isolate the lower sheet 20 from the absorbent body 24 to improve circulation of air and effectively reduce the wetting of the face facing the garment of the lower sheet 20. The ventilation layer 32 can also help to distribute the fluid exudates to parts of the absorbent body 24 which do not directly receive the discharge. The diaper 10 may further include an emergence management layer 34 located between the topsheet 22 and the absorbent body 24 to prevent fluid stagnation and stagnation and to improve air exchange and distribution of fluid exudates within the fluid. diaper 10 The diaper 10 may be of various suitable shapes. For example, the diaper 10 may have a global rectangular shape, a T shape or a watch shape of approximately. In the embodiment shown, the diaper 10 has a generally I-shape. The diaper 10 further defines a longitudinal direction 36 and a lateral direction 38. Other suitable diaper components which can be incorporated on the absorbent articles of the present invention include the containment fins, the waist flaps, the elastomeric side panels and the like. which are generally known to those skilled in the art.

Examples of suitable cloth configurations for use in connection with the present application which may include other diaper components suitable for use on diapers are described in US Pat. Nos. 4,798,603 issued on October 17, ener of 1989 to Meyer and others; 5,176,668 issued on January 5, 199 to Bernardin; 5,176,672 issued on January 5, 1993 to Bruemme et al .; 5,192,606 granted on March 9, 1993 to Proxmire others, and 5,509,915 granted on April 23, 1996 to Hanson others, whose descriptions are incorporated herein by reference.

The various components of diaper 10 are integrally assembled together using various types of suitable attachment means, such as adhesive, sonic bonds, thermal bonds or combinations thereof. In the embodiment shown, for example, the topsheet 22 and the bottom sheet 20 are assembled together and to the absorbent body 24 with lines of adhesive, such as hot-melt pressure-sensitive adhesive. Similarly, other diaper components, such as the elastic members 26 and 18, the fastening members 30, and the ventilation and emergence layers 32 and 34 can be assembled into the diaper article by employing the above-identified bonding mechanisms. .

The lower sheet 20 of the diaper 10 is representatively illustrated in Figures 1 and 2, and is composed of a material essentially permeable to vapor. The lower sheet 2 is generally constructed to be permeable to at least water vapor and has a water vapor transmission rate of at least about 1,000 g / square meter / 24 hours., Desirably of at least from about 1,500 g / square meter / 24 hours, more desirably from at least about 2,000 g / square meter / 24 hours, and even more desirably from at least about 3,000 g / square meter / 24 hours. For example, the lower sheet 20 can define a rate of water vapor transmission of from about 1,000 around 6,000 g / square meter / 24 hours. The materials which have a water vapor transmission rate lower than those mentioned above do not allow a sufficient amount of air exchange and undesirably increase levels of skin hydration.

The lower sheet 20 is also in desirable form essentially impermeable to liquid. For example, the bottom sheet can be constructed to provide a head water value of at least about 60 centimeters, desirably of at least about 80 centimeters, and more desirably of at least about 100 centimeters when undergoes the hydrostatic pressure test. Materials which have lower hydro head values than those mentioned above undesirably result in the transfer of liquids, such as from urine, during use. Such transfer of fluid may undesirably result in a sticky, wet feeling on the lower sheet 20 during e use.

The lower sheet 20 can be composed of any suitable materials which already directly provide the above desired levels of liquid impermeability and air permeability or, alternatively, the materials which can be modified or treated in some way to provide such levels. In one embodiment, the bottom sheet 20 can be a woven fibrous web constructed to provide the required level of liquid impermeability. For example, a non-woven fabric composed of polymer fibers joined with co-melt spinning or blowing can be selectively treated with a water-repellent coating or laminated with a vapor-permeable and liquid-impermeable polymer film to provide the bottom sheet 20. In a particular embodiment of the invention, the bottom sheet 20 may comprise a woven fabric composed of a plurality of randomly deposited hydrophobic thermoplastic meltblown fibers which are sufficiently bonded or otherwise connected to each other to essentially provide a fabric. liquid impermeable and essentially vapor permeable. The lower sheet 20 may also comprise a vapor permeable nonwoven layer which has been partially coated or otherwise configured to provide liquid impermeability in selected areas.

Examples of materials suitable for the lower sheet 20 are also disclosed in United States of America Patent No. 5,482,765 issued January 9, 1996 in the name of Bradley et al. Entitled "LAMINATE OF TEL NO WOVEN" WITH INCREASED BARRIER PROPERTIES "; patent application of the United States of America series No. 08 / 622.90 filed on March 29, 1996 in the name of Odorzynski et al. and entitled "ABSORBENT ARTICLE WHICH HAS A GRADIENT D CAPACITY TO BREATHE"; Patent application of the United States of America series No. 08 / 668,418 filed on June 21, 1996, in the name of Good and others and entitled "ABSORBENT ARTICLE WHICH HAS A BOTTOM LEAF WITH A CAPACITY TO BREATH COMPOUND", and U.S. Patent Application No. 08 / 882,712, filed Jun. 25, 1997, in the name of McCormack et al., entitled "LOW CALIBER FILM AND FILM LAMINATES-NOT WOVEN", whose descriptions are Incorporate here by reference.

In a particular embodiment, the lower sheet 20 is provided by a microporous film / non-woven laminate material comprising a non-woven material bonded with laminate to a microporous film. Co-bound nonwoven comprises filaments of about 1.8 denier extruded from an ethylene copolymer with about 3.5 per cent by weight of propylene and which defines a basis weight of from about 17 to about 25 grams per square meter. The film comprises a coextruded and melted film having calcium carbonate particles there and which defines a basic weight of about 58 grams per square meter before stretching. The film is preheated, stretched and tempered to form micropores and then laminated to a nonwoven joined with yarn. The base material of the resulting microporous film / nonwoven laminate has a basis weight d from about 30 to about 60 grams per square meter and a water vapor transmission rate of from about 3,000 to about 6,000 g / square meter / 24 hours. Examples of such film / non-woven laminate materials are described in greater detail in U.S. Patent Application No. 08 / 882,712 filed June 25, 1997 in the name of McCormack et al., and entitled "LOW CALIBER FILMS AND FILM / NON-WOVEN LAMINATES", the description of which has been incorporated herein by reference.

The upper sheet 22, as shown representatively in FIGS. 1 and 2, suitably presents a face surface to the body which is docile, of soft feel and non-irritating to the wearer's skin. In addition, the upper blade 22 may be less hydrophilic than the absorber body 24, to present a relatively dry surface to the user and may be sufficiently porous to be permeable to the liquid allowing the liquid to easily penetrate through the thickness. A suitable top sheet 22 can be manufactured from a wide selection of fabric materials, such as porous foam, cross-linked foams, perforated plastic films, natural fibers (e.g. cotton or wood fibers), synthetic fibers (e.g. of polyester od polypropylene), or a combination of synthetic natural fibers. The topsheet 22 is suitably used to help isolate the wearer's skin from liquids maintained in the absorbent body 24.

Various woven and knitted fabrics may be used for the topsheet 22. For example, the topsheet 22 may be composed of a meltblown or spunbond fabric of polyolefin fibers. The top sheet may also be a carded fabric composed of natural and / or synthetic fibers. The top sheet may be composed of essentially hydrophobic material, and the hydrophobic material may, optionally, be treated with a surfactant or otherwise processed to impart a desired level of wettability and hydrophilicity. In the particular embodiment of the present invention, the topsheet 22 comprises a polypropylene fabric bonded with non-woven yarn composed of fibers of about 2.8-3.2 denier formed into a fabric having a basis weight of about 22. grams per square meter and a density of about 0.06 grams per cubic centimeter. The top sheet 22 can be treated on the surface with an effective amount of a surfactant, such as about 0, percent by weight of a surfactant commercially available from Hodgson Textile Chemicals Co. under the trade designation AHCOVEL BASE N-62 .

The absorbent body 24 of the diaper 10 as representatively illustrated in Figures 1 and 2 may suitably comprise a matrix of hydrophilic fibers, such as cellulose fluff, mixed with particles of high absorbency material commonly known as a superabsorbent material. In a particular embodiment, the absorbent body 24 may comprise a cellulosic fluff matrix such as wood pulp fluff, and superabsorbent hydrogel-forming particles. The wood pulp fluff can be interchanged with synthetic, polymeric and co-melt blown fibers or with a combination of melt blown fibers and natural fibers. The superabsorbent particles can be essentially mixed homogeneously with the hydrophilic fibers or they can be mixed non-uniformly. Alternatively, the absorbent body 24 may comprise laminate of fibrous fabrics and superabsorbent material or other suitable means for maintaining the superabsorbent material in a localized area.

The absorbent body 24 can have any of a number of shapes, for example, the absorbent body can be rectangular, I-shaped or T-shaped. It is generally preferred that the absorbent body 24 be narrower in the middle section than in the back front waist sections of the diaper 10. The absorbent body 24 may be provided by a single layer or, alternatively may be provided by multiple layers, all of which does not require extending to the full length and width of the absorbent body 24. In A particular aspect of the invention, the absorbent body 24 may be generally T-shaped with the cross bar of the "T" extending laterally corresponding generally to the front waist section 1 of the absorbent article for improved performance especially for male infants. In the illustrated embodiments, for example, the absorbent body 24 through the front waist section 12 of the article has a n width in the transverse direction of about 18 centimeters, the narrowest part of the intermediate section 16 has a width d about 7.5 centimeters and a section of waist posterior 14 has a width of about 11.4 centimeters.

The size and absorbent capacity of the absorbent core 24 must be compatible with the size of the intended user and the liquid load imparted by the intended use of the absorbent article. In addition, the size and absorbent capacity of the absorbent body 24 can be varied to accommodate users ranging from infants to adults. Furthermore, it was found that with the present invention, the densities and / or l base weights of the absorbent body 24 can be varied. In a particular aspect of the invention, the absorbent body 24 has an absorbent capacity of at least about 3 grams of synthetic urine.

In embodiments where the absorbent body 24 includes the combination of hydrophilic fibers, high-absorbency particles, hydrophilic fibers, high-absorbency particles, hydrophilic fibers and high-absorbency particles can form an average weight for the absorbent body 24 which is Within range of about 400-900 grams per square meter. In certain aspects of the invention, the average composite weight of such an absorbent body 24 is within a range of about 500-800 grams per square meter, preferably they are within the range of about 550-7 grams per square meter to provide the desired operation.

To provide the thinness dimension to the various configurations of the inventive absorbent article, the absorbent body 24 can be configured with a volume thickness which is not more than about 0 centimeters. Preferably, the volume thickness is not about 0.53 centimeters, and more preferably is not more than about 0.5 centimeters to provide improved benefits. The volume thickness was determined at a restriction pressure of 0.2 pounds per square inch (1.38 kPa).

The high-absorbency material can be selected from natural, synthetic, modified natural materials and polymers. The high-absorbency materials can be inorganic materials such as silica gels, organic compounds, such as crosslinked polymers. The term "cross-linked" refers to any means for effectively making the materials normally soluble in water essentially insoluble or water-swellable. Such means may include, for example, physical entanglement, crystalline domains, covalent bonds, complexes and ionic associations, hydrophilic associations such as hydrogen bonding and hydrophobic associations or Van der Waals forces.

Examples of polymeric, high-absorbency synthetic materials include the alkali metal and ammonium salts of poly (acrylic acid) and poly (methacrylic acid), poly (acrylamide), poly (vinyl ethers) copolymers of maleic anhydride with ethers of vinyl and alf olefins, poly (vinyl pyrrolidone), poly (vinyl morpholinone poly (vinyl alcohol) and mixtures and copolymers thereof Additional polymers suitable for use in the absorbent include natural and modified natural polymers such as the grafted starch of hydrolyzed acrylonitrile, grafted starch of acrylic acid, methyl cellulose, carboxymethyl cellulose, hydroxypropyl cellulose, natural gums, such as alginates, xanthan gum, locust bean gum and the like, mixtures of fully or partially synthetic absorbent polymers they can also be used in the present invention.

The high-absorbency material can be any of a wide variety of geometric shapes. With a general rule, it is preferred that the material of the absorbency be in the form of discrete particles. However, the high-absorbency material may also be in the form of fibers, flakes, rods, spheres, similar needles. In general, the high-absorbency material is present in the absorbent body in an amount of about 5 to about 90 percent by weight, desirably in an amount of at least about one percent by weight., and still more desirably in an amount of at least about 50 percent by weight based on the total weight of the absorbent body 24. For example, in a particular embodiment, the absorbent body 24 can comprise a laminate which includes at least less about 50 percent by weight and desirably at least about 70 percent by weight of high absorbent material overwrapped by a fibrous web or other suitable means to maintain the high absorbency material in a localized area.

An example of a high absorbency material suitable for use in the present invention is the SANWET IM 3900 polymer available from Hoechst Celanese, a business having offices in Portsmouth, Virginia. Suitable OTR superabsorbents may include W45926 or FAV SXM 880 polymer obtained from Stockhausen, a business having offices in Greensboro, North Carolina.

Optionally, an essentially hydrophilic tissue wrapping sheet (not shown) can be employed to help maintain the integrity of the structure of the absorbent body 24. The tissue wrapping sheet is typically positioned around the absorbent body on at least two surfaces It is composed of an absorbent cellulosic material, such as a creped wadding or a tissue with high resistance to humidity. In an aspect of the invention, the tissue wrapping can be configured to provide a transmission layer which helps to rapidly distribute the liquid over the absorbent fiber mass comprising the absorbent body.

The absorbent body 24 of the different aspects of the present invention further includes a plurality of high air permeability zones which allow air to vapor easily pass through the absorbent body 24 through the lower vapor permeable sheet 20 outside. of diaper 10 inside the ambient air. For example, as representatively illustrated in Figures 1 and 2, the absorbent body 2 may include a plurality of air passages 40 which provide the absorbent body 24 with the high air permeability zones or regions 42. In the illustrated embodiment the parts of the absorbent body 24 adjacent to the air ducts 40 provide high absorption areas or regions 44. The high air permeability zones 42 are designed to provide maximum air exchange from the absorbent body 24 while the areas of High absorption 44 is designed to receive and retain most body exudates. The absorbent body 24 can define any number of upper air permeability zones 42 which provide the improved air exchange. Desirably, the absorbent body 24 defines at least three and more desirably at least 5 different zones of high air permeability 4 for improved operation.

The high air permeability zones 42, as well as the air passages 44 as representatively illustrated in Figures 1 and 2, are configured to increase the breathability of the article to reduce the hydration of the user's skin during use without it allowed excessive condensation of steam, such as urine, on the surface facing the garment of the lower sheet 20. The condensation of steam on the outer surface of the diaper 1 can undesirably dampen the wearer's or user's clothes. The high air permeability zones 42 are generally located in the area of the diaper over which air and vapor can be transferred from the topsheet 22, through the absorbent body 24 and any other layers of interlayer material layers, and outside. of the lower vapor permeable sheet 20. For example, the air permeability zones 42 can be located through the entire absorbent body 24 or can be located selectively in those regions of the absorbent body 24 which provide the maximum air exchange, such as the intermediate section 16 of diaper 20. In a particular embodiment, the high air permeability zones 42 are located in the front and intermediate sections 12 and 16, respectively, of the diaper 10 for improved air exchange.

The high absorption zones 44, on the other hand, are designed to transfer a high level of air and vap from the interior of the diaper. Therefore, the exchange of ai from the upper sheet 22 of the diaper 10 to the lower sheet 20 of diaper and inside the ambient atmosphere (outside of the diaper occurs generally through the absorbent body 24 in the high air permeability zones 42. Some exchange of air through the absorbent body 24 can also occur in the high absorption zones 44 to a limited degree.

Areas of high air permeability can have any desired configuration including rectangular, circular, hourglass, oval, and similar, and may also include selected lateral longitudinal strips or multiple regions which may be located intermittently. For example, in FIGS. 1 and 2, the high air permeability zones 42 are provided by a plurality of air passages 40 openings through the absorbent body 24 which have a generally circular configuration. In such a configuration, the high absorption zones 44 comprise the non-perforated portions of the absorbent body 24 between the air conduits 40.

The high air permeability zones 42 can have any desired dimensions which effectively provides improved air exchange while s prevents excessive condensation of the vapor from the absorbent body 24 through and on the face surface of the sheet. Desirably, the air permeability zones 42 can define a total area of from about 5 to about 75 percent, more desirably at least about 10 percent, even more desirably from about 10 to about 70 percent, and still more desirably from about 10 to about 60 percent of the total surface area of the absorbent body 24 of diaper 10. For example, in a diaper intended for use in an infant size medium, the high air permeability zones 42 can define a total area from about 6 about 90 square centimeters.

When the total area of the air permeability zones 42 is greater than the above-mentioned amounts, the diaper 10 may exhibit an undesirable amount of vapor condensation on the exposed face of the lower sheet 20 undesirably resulting in a sticky feeling on the outer surface of the diaper. Whereas, when the total area of the air permeability zones 42 is less than the above-mentioned amounts, the diaper 10 may exhibit a low level of air exchange resulting in higher levels of skin hydration which may lead to undesirably to skin irritation and rash.

The high air permeability zones 42 of absorbent body 24 of diaper 10 as representatively illustrated in Figures 1 and 2, are constructed to be essentially impermeable to at least air preferably permeable to water vapor. For example, the high air permeability zones 42 of the absorbent body 2 define a Frazier Porosity value which is at least about 10 percent, more desirably at least about 20 percent, and yet more desirably of at least about 50 percent greater than the value d Frazier porosity of the high absorption zones 44 of the absorbent body 24. As used herein, the term "Frazier porosity refers to the value determined according to the Test Frazier porosity established below When the air permeability zones exhibit Frazier Porosity values which are greater than those indicated above, the diaper 1 may exhibit a low level of air exchange resulting in higher levels of hydration of the skin which can undesirably lead to irritation and skin rash Areas of high air permeability can be provided in various ways. The high air permeabilized zones 42 can be integral parts of the absorbent body 2 of the absorbent article or can be provided by openings, holes or open spaces in the absorbent body 24. For example, the parts of the absorbent body 24 can be discontinued or removed To provide the zones 42 Alternatively the high air permeability zones 4 can be provided by parts of the absorbent body 24 which are constructed to absorb less fluid exudates thereby resulting in improved air flow through such parts in use. For example, parts of the absorbent body 24 may be devoid of or contain essentially less high-absorbency material than other parts of the absorbent body 24 to provide such improved air flow. The parts of the absorbent body 24 can otherwise be treated with a solution which makes them hydrophobic to provide the high air permeability zones 42 in selected areas. In other alternate configurations, the high air permeability zones 42 can provide by creating gaps or holes in the absorbent body 2 and placing other materials having an air permeability higher than that of the absorbent body 24, such as those materials described below. as being suitable for the emergence management layer 34, in the holes or holes.

Examples of various configurations of the absorbent body 24 according to the different aspects of the present invention are representatively illustrated in Figures 1 6. For example, in Figures 1 and 2, the air permeability zones 42 in the absorbent body 24 s provide through a plurality of air ducts 40 perforations through the absorbent body 24. In illustrated embodiment, the air ducts 40 are intermittently positioned along the full length of the width of the absorbent body 24. The ducts of air illustrated 40 are circular and define a diameter of about 1.27 centimeters and a total open area of about percent of the total surface area of the absorbent body 2 In Figures 3 and 4, the absorbent body 24 is in the form of discrete segments 46 which are spaced apart along the longitudinal direction 36 of the cloth 10. In such a configuration, the high air permeability zones 42 are provided. by the spaces between the discrete segments 46 of the absorbent body 24. The absorbent body 2 may include any number of segments 46 having a variety of shapes and sizes. In the illustrated embodiment, absorbent body 24 includes four different segments 4 spaced apart in the longitudinal direction 36 of the cloth 10. The segments illustrated 46 are generally rectangular in shape and define a width which is less than an absorbent body width 24 dual, in the illustrated embodiment, is defined by the width of the emergence management layer 34 and d the ventilation layer 32 as described below. Alternatively, the segments 46 may define a width e which is essentially equal to the width of the absorbent body 24 To help maintain the segments 46 in the spaced apart relationship, the segments 46 may be contained between the two sheets of material such as the wrapping sheet (not shown) or the emergence management layer 34 and the ventilation layer 32. In the illustrated embodiment the segments 46 include laminate of high absorbency material between two sheets or layer of material and the high permeability zones d to the air 4 provided by the spaces between the segments 46 define open area of about 40 percent of a total surface area of the absorbent body 24.

In Figures 5 and 6, the air permeability zones 42 in the absorbent body 24 s provide by a plurality of air passages 40 openings through the absorbent body 24 similar to the embodiment illustrated in Figures 1 and 2. However , in the embodiment illustrated in Figures 5 and 6, air ducts 40 are located in the absorbent body 24 in the front waist section 12 and in the intermediate section 16 of diaper 10 and not in the rear waist section 14. Further, in the embodiment illustrated in Figures 5 and 6, the absorbent body 24 includes an upper layer 48 and a lower layer 5 with the upper layer 48 extending only along a portion of the length of the absorbent body 24. In In the configuration, the majority of the absorbent body 24 can be located in the front and intermediate waist sections 1 and 16 of the diaper 10 for improved absorption and reduced cost. The. illustrated air ducts 40 are circular define a diameter of about 1.27 centimeters and a total open area of about 12 percent of the total surface area of the absorbent body 24.

Due to the thinness of the absorbent body 24 and high absorbency material within the absorbent body 24, the liquid intake rates of the absorbent body 24, by itself may be very low, or may not be adequately supported on multiple discharges of liquid to the liquid. absorbent body 24 To improve the intake of the general liquid and air exchange, the diaper of the various aspects of the present invention may further include a porous liquid permeable layer of emergence handling material 34 as representatively illustrated in FIGS. and 2The emergence management layer 34 is typically less hydrophilic than the absorbent body 24, and has an operable level of density and a basis for collecting and temporarily retaining liquid emergencies rapidly, to transport the liquid from its entry point. Initially and to essentially completely release the liquid to other parts of the absorbent body 24. This configuration can help to prevent liquid from pooling on the part of the absorbent garment placed against the skin of the user thereby reducing the It felt wet from the user. The structure of the emergence management layer 34 also generally improves air exchange within the diaper 10.

Various woven and non-woven fabrics can be used to construct the emergence management layer 34. For example, the emergence layer 34 can be a composite layer of a meltblown or synthetic fiber spunbond fabric, such as fiber of polyolefin. The emergence handling layer 34 can also be a carded and bonded fabric or air-laid fabric composed of natural synthetic fibers. The carded and bonded fabric may, for example, be a thermally bonded fabric which is bonded using the low melt binder fibers, the powders or the adhesive. The fabrics can optionally include a mixture of different fibers. The emergence management layer 34 may be composed of an essentially hydrophobic material, and the hydrophobic material may optionally be treated with a surfactant processed in another manner to impart a desired level of wettability and hydrophilicity. In a particular embodiment the emergence management layer 34 includes a non-woven hydrophobic material having a basis weight of from about 30 about 120 grams per square meter.

For example, in a particular embodiment, the emergence management layer 34 may comprise a bonded and knitted fabric, a non-woven fabric which includes bicomponent fibers and which defines a global basis weight of about 38 grams per square meter. The emergement management layer 34 in such a configuration can be a homogeneous composite mixture of about 60 percent by weight bicomponent polyethylene / polyester (PE / PET) sheath-core fibers, which have a fiber denier. about 3 d and about 4 percent by weight of single component polyester fibers which have a fiber denier of about 6 d and which have fiber lengths from about 3.8 about 5.08 centimeters.

In the illustrated embodiments, the emergence management layer 34 is arranged in a direct contact liquid communication with the absorbent body 24. The emergence management layer 34 can be operably connected to the topsheet 22 with a conventional adhesive pattern. such as a swirl adhesive pattern. In addition, the emergence management layer 34 can be operably connected to the absorbent body 24 with a conventional pattern of adhesive. The amount of adhesive added should be sufficient to provide the desired levels of bonding, but should be sufficiently low to avoid excessively restricting the movement of the liquid from the topsheet 22 through the emergence management layer 34 and into the absorbent body. 24 The absorbent body 24 is placed in a liquid communication with the emergence management layer 3 to receive the liquids released from the emergence management layer and to retain and store the liquid. In the illustrated embodiments, the emergence management layer 3 comprises a separate layer which is placed on another separate cap comprising the absorbent body 24, thereby forming a dual layer array. The surge management layer 34 serves to quickly collect and temporarily retain the discharged liquids, to transport such liquids from the initial point of contact and to spread the liquid to other parts of the emergence management layer 34 and then to essentially release the form. complete such liquids inside the layer layers comprising the absorbent body 24.

The emergence management layer 34 can be any desired shape. Suitable shapes include, for example, the circular, the rectangular, the triangular, the trapezoidal, the oblong, the dog bone, the hourglass shape, or the oval. In certain embodiments, for example, the emergence management layer may be generally rectangular in shape. In the illustrated embodiments, the emergence management layer 34 is coextensive with the absorber body 24. Alternatively, the emergence management layer 34 may extend over only a part of the absorbent body 24. E where the emergence management layer 34 extends over only partially the length of the absorbent body 24, the emergence management layer 34 may be selectively placed. any part along the absorbent body 24. For example, the emergence management layer 34 can operate efficiently when it is off-center towards the front waist section 12 of the garment. The emergence management layer 34 can also be centered approximately around the longitudinal center line of the absorbent body 24.

Additional materials suitable for emergence management cap 34 are set forth in United States of America Patent No. 5,486,166 issued January 23, 1996 in the name of C. Ellis et al. And entitled "CAPA D SURGERY. OF FIBROUS NON-WOVEN FABRIC FOR ABSORBENT ARTICLES FOR PERSONAL CARE AND SIMILAR "; U.S. Patent No. 5,490,846 issued February 13, 199 in the name of Ellis et al. and entitled "FABRICS OF IMPROVED EMERGENCY RISK MANAGEMENT FOR ABSORBENT ARTICLES FOR PERSONAL CARE AND THE LIKE" and U.S. Patent No. 5,364,382 issued November 15, 1994 in the name of Latimer et al. entitled "ABSORBENT STRUCTURE HAVING MANAGEMENT OF EMERGENCY OF IMPROVED FLUID PRODUCTS INCORPORATING THEMSELVES", the description of which is Incorporated here by reference.

As representatively illustrated in FIGS. 1 and 2, the diaper 10 may also include a ventilation layer 32 located between the lower sheet 20 and the absorbent body 24. The ventilation layer 32 serves to facilitate the movement of the air within and through the diaper 10 and preventing the lower flap 20 from being used in surface-to-surface contact with at least a part of the absorbent body 24 Specifically, the ventilation layer 32 serves as a conduct through which air and water vapor they can move from the absorbent body 24 through the vapor permeable lower sheet 20.

The ventilation layer 32 can be formed from the materials described above as being suitable for the emergence management layer 34 such as non-woven fabrics (eg, spunbonded, meltblown or carded) woven or fibrous webs composed of natural fibers. and / or synthetic polymer fibers. Suitable fibers include, for example, acrylic fibers, polyolefin fibers, polyester fibers or mixtures thereof. The ventilation layer 32 can also be formed of a porous foam material such as open cell polyolefin foam, a polyurethane foam and the like. The ventilation layer 32 may include a single layer of material or a composite of two more layers of material. In a particular embodiment, the ventilation layer 32 includes a hydrophobic nonwoven material having a thickness of at least about 0.10 centimeter finished under a restriction pressure of 0.05 pounds per square inch (0.34). kPa) and a basis weight of from around d 20 to about 120 grams per square meter. For example, the ventilation layer 32 may comprise a bonded carded fabric, a non-woven fabric which includes component fibers which defines an overall basis weight of about 83 grams per square meter. The ventilation layer 32 in such a configuration can be a homogeneous mixture composed of about 60 percent by weight of polyethylene / polyester (PE / PET) sheath-core bicomponent fibers which have a fiber denier of about 3. and about 40 percent by weight of single component polyester fibers which have a fiber denier of about 6 d and which has fiber lengths of from about 3.8 to about 5.0 centimeters.

The ventilation layer 32 may be of any desired shape. Suitable shapes include, for example, circular, rectangular, triangular, trapezoidal, oblong, dog bone, hourglass or oval shape. The ventilation layer 32 can extend further, completely over or partially over the absorbent body 24. For example, the ventilation layer 32 can suitably be located on the intermediate section 16 of the diaper 10 and be essentially centered side by side with respect to the longitudinal centerline 36 of the diaper 10. It is generally desired that the entire absorbent body 24 be covered with the ventilation layer 32 to avoid essentially any surface to surface contact between the bottom sheet 20 and the absorbent body 24. In the illustrated embodiments, the The ventilation layer 32 is coextensive with the absorbent body 24. It allows a maximum degree of air exchange with minimal wetting on the surface facing the garment the lower sheet 20.

In the illustrated embodiments, the ventilation layer 32 is arranged in a liquid communication with direct contact with the absorbent body 24. The ventilation layer 32 can be operatively connected to the lower flap 20 with a conventional pattern of adhesive, such as adhesive pattern. swirl. In addition, the ventilation layer 32 can be operably connected to the absorbent body 2 with a conventional adhesive pattern. The amount of adhesive added should be sufficient to provide the desired level of bonding, but should be sufficiently low to avoid excessively restricting movement of air and vap from the absorbent body 24 and through the lower sheet 20 The ventilation layer 32 can furthermore serve to quickly collect and temporarily retain the discharged liquids, which pass through the absorbent body 24 and in particular, through the high air permeability zones 42 within the absorbent body 24. The layer The ventilator 32 can then transport such liquids from the initial point of contact and spread the liquid to other parts of the vent cap 32, and then essentially completely release such liquids to the layer or layers comprising the absorbent body 24.

The various embodiments of the present invention, as representatively illustrated in FIGS. 6, advantageously provide improved absorbent articles which exhibit essentially reduced levels of hydration of the wearer's skin when used in comparison to conventional absorbent articles. The reduced levels of hydration of the skin promote a drier and more comfortable skin and make the skin less susceptible to the viability of microorganisms. Therefore, user-absorbent articles made in accordance with the present invention have reduced skin hydration and can lead to a reduction in the incidence of skin irritation and skin rash.

PROOF PROCEDURES Hydrostatic Pressure Test The Hydrostatic Pressure Test is a measure of the liquid barrier properties of a material. In general, the Hydrostatic Pressure Test determines the height of water (in centimeters) in a column which will support the material before a predetermined amount of water passes through. A material with a higher hydro head value indicates that it is a greater barrier to the penetration of the liquid than a material having a lower hydro head value. The Hydrostatic Pressure Test was carried out according to Method 5514 - of the Standard Federal Test Methods No. 191A Porosity test Frazier The Frazier Porosity values referenced in the present disclosure can be determined using a Frazier Air Permeability Tester (from Frazier Precision Instrumen Co., of Gaithersburg, Maryland) and Method 5450, Standard Federal Test Methods No. 191A. For the purposes of the present invention, the test was carried out with a sample 1 which measures 8 inches X 8 inches.

Water Vapor Transmission Test A suitable technique to determine the WVT value (rate of water vapor transmission) of a material is com. For the purposes of the present invention, circular samples of 3 inches diameter (76 millimeters) of test material and from a control of Celguard® 250 material (Hoechst Celanese Corporation) were cut. Two or three samples were prepared for each material. The test cups used for the test are hardened aluminum, flanged, two inch deep and come with a mechanical seal and neoprene gasket. The cups are distributed by Thwing-Alber Instrument Company, of Philadelphia, Pennsylvania under the designation Vapometer Cup # 681. One hundred milliliters of distilled water are poured onto each cup of Vapometer and each of the individual samples of test materials and control material are placed through the open top area of an individual cup. The bolted flanges are tightened to form a seal along the edges of the cups leaving the associated test material or control material exposed to the ambient atmosphere over a circular area of 62 millimeters in diameter (an exposed and open area). around 30 cm2). The cups are then heavy, placed on a tray, and placed in a forced air oven at 100 ° F (38 ° C). The oven is a constant temperature oven with an external air circulating through it to prevent the accumulation of water vapor inside. A suitable forced air oven is, for example, a Blue M Power-O-Matic 6 furnace distributed by Blue M Electric Company, of Blue Island, Illinois. After 24 hours, the cups are removed from the horn and weighed. The water vapor transmission rate value of the preliminary test is calculated as follows: Test WVTR = [(weight loss grams over 24 hours) x 7571] (g / ra2 / 24 hours) 24 The relative humidity inside the oven is not specifically controlled. Under predetermined set conditions of 100 ° F and ambient relative humidity, the water vapor transmission rates for the Celguard 2500 have been determined to be 5,000 g / m2 / 24 hours. Therefore, the Celguard 2500 runs as a control sample with proof. The Celguard 2500 is a 0.0025 cm thick film composed of a microporous polypropylene.

Skin Hydration Test The hydration values of the skin are determined by measuring a total evaporative water loss (EWL) and can be determined by using the following test procedure.

The test was carried out on an infant partially trained for the toilet who does not have lotions or ointments on the skin and who have not bathed within 2 hours prior to the test. Each infant tests a diaper during each test session. The test diapers include a test code and a control code. The test diapers (test code and control code) are random.

Each test diaper is weighed before and after use to verify the volume of liquid added in the diaper. A felt tip pen was used to mark "X" in the target area within the diaper, with the "X" positioned 6.5 inches below the upper front edge of the diaper centered side by side. EWL measurements are taken with an evaporimeter, such as the Evaporimeter E instrument distributed by Servomed AB of Stockholm, Sweden. Each test measurement is taken over a period of two minutes with the EWL values taken once per second (a total of 120 EWL values). The digital output of the Evaporimeter EP1 instrument gives the rate of evaporative water loss (EWL) in g / m / hour. The skin hydration values (SHV) are in units total amount of water loss per unit area measured during a sampling period of two minutes and calculated as follows. 120 SHV (g / m2 / hour) = L (EWL) n n = l 120 A measure of hydration value of preliminary pi was taken after a "drying" period of minutes when the infant wears only a long shirt or dress and is in a supine position. The measurement was taken on the lower abdomen of the infant, in a region corresponding to the target area of the diaper, using the evaporimeter for the purpose of establishing the hydration value of the initial pi of the infant's skin in the target area of the diaper. If the hydration value of the preliminary skin is less than 10 g / m2 / hour, then a diaper is placed over the infant. the hydration value of the skin is preliminarily greater than g / m2 / hour, the "drying" period is extended until it obtains a reading below 10 g / m2 / hour. Before securing the diaper over the infant, a tube is placed to direct a flow of liquid to stick in the pre-marked target area. Once the diaper is secured, add 210 milliliters of 0.9-percent aqueous water by weight in three discharges of 70 milliliters each at a rate of 15 milliliters / second with a delay of 45 seconds between insults.

The infant wears the diaper for 60 minutes after which the diaper is removed and a test measurement of skin hydration is taken on the lower abdomen corresponding to the target zone mark of the diaper. The measurement is over a period of two minutes. The used diaper is then heavy. Measurements of relative humidity and temperature within the diaper can be taken before the hydration measurement of the skin is taken. The test procedure then repeated the next day for each infant using diaper type (test or control) which the infant did not use. The control diaper provides a standardized basis for comparing the performance of the diaper configuration that is being tested and evaluated. The control diapers used were the tests carried out in connection with the commercially available HUGGIES® Supreme diaper examples sold by Kimberly-Clark Corporation.

The data is discarded for any infants which have been added to the load of salt water solution. The value reported for the average net skin hydration value (grams / m2 in one hour) is the arithmetic means for all infants of the skin hydration value after use, taken in the lower abdomen (target zone mark) minus the hydration value of the skin measured in the lower abdomen before placing the diaper on the infant (after the "drying" period). A separate average net skin hydration value was determined for the test-code diapers and for the control-code diapers.

The net skin hydration value was determined as follows: Net SHV, = Y-Z Where : Y = hydration value of the skin measured with the target zone mark of an individual infant.

Z = skin hydration value of ba line measured on the lower abdomen after the "dried" period before placing the diaper on the infant.

SHVi = hydration value of the skin for an individual infant.

So, N Main SHV Net = i SRVi Net i = l N Where: N = number of infants under study.

The percent reduction in hydration of the skin was determined as follows: N \% Reduction = / [((C-D) / C) xl00] i = l N Where: C = SHV ^ Net for control diaper code D = SHV;, Net for test diaper code.

N = number of infants in the study.

Gas Tracker Test The tracer gas test is a measure of the rate of air exchange in the garments such as absorbent articles and is a stable flow test / steady state generally described in the TAPPI DIARY, Volume 80, No. 9, September. 1997. In general, the exchange rate values are calculated from the mass exchange measured within the garment. The test involves injecting a gas tracked at a constant rate into the article near the outer surface of a manikin's torso while the article is secured around the manikin. Simultaneously, the concentration of tracer gas in the air space between the article and the manikin is measured by removing a sample at the same constant rate as that of the injection. The rate of air exchange is then determined based on the mass balances of the tracer gas and the air within the space in question. The Gas Tracker Test is completed as follows: Equipment 1. Manikin - The test was carried out with the size diapers Step 3 or Step 4 designated for infant weighing from about 16 to about 28 pounds, and d from around 22 to about 37 pounds, respectively the diapers were placed over the mannequins which has the following dimensions: Step 3 height (waist to knee) 26 cm circumference at the waist 42 cm circumference at the hips 44 cm circumference thigh 22 cm Step 4 height (waist to knee) 28 cm circumference at the waist 48 cm circumference at the hips 51 cm circumference thigh 27 centimeter 2. A test area which is environmentally controlled at 20 ° C and at 50% relative humidity. 3. Analyzer C02 - An infrared C02 analyzer such as a Model 17515A commercially available from Vacu-Me Vacumetrics, 4483 McGrath Street # 102, Ventura, California. 4. Rotameters - Rotameters to maintain gas flow rates such as Matheson Rotameter Model TS-3 commercially available from Specialty Gases Southeast Inc., 349 Peachtree Parkway, Suwanee, Georgia.

. Gas Cylinders - Two cylinders ga ga medical class calibrated at a pressure of 4 kPa Specialt Gases Southeast Inc., 3496 Peachtree Parkway, Suwanee Georgia. The tracer gas included 5% C02 and air and the calibration gas is 100% air.

Process 1. Turn on the C02 analyzer. After it has been on for 30 minutes, calibrate the analyzer with the calibration gas and adjust the flow control to achieve a flow rate of 150 cubic centimeters per minute through the analyzer. 2. Place the diaper that is going to be tested on the mannequin 3. Turn on the flow of tracer gas C02. The flow rate of the tracer gas injected into the space between the diaper and the manikin must be equal to the sample flow rate through the CO analyzer (150 cubic centimeter / minute). 4. Measure and record the concentration (C) of the tracker (C02) in the air space between the diaper and the manikin every 10 seconds for 20 minutes. Data on the last 10 minutes are averaged and used to calculate the air exchange rates as follows: Air Exchange Rate = 150 cc / min * [(Ct-C) / (C-C0)] where, Ct = concentration of the tracer gas (5%) C = concentration of the tracer gas in the space being measured.

C0 = concentration of the tracer gas in the chamber environment (, 04%).

The Dry Air Exchange Rate is the air exchange rate as determined according to the aforementioned procedure before the diaper had been subjected to any insults. The Humid Air Exchange Rate e the air exchange rate determined according to the procedure mentioned above except that once the diaper is secured in the manikin, 180 milliliters were added.

(Step 3) or 210 milliliters (Step 4) of a salad water solution of 0.9 percent by weight in three discharges of 60 or 7 milliliters each at a rate of 15 milliliters / second with a 45-second delay between the insults. The ratio of the Wet Air Exchange Rate / Dry Air Exchange Rate was determined by dividing the Wet Air Exchange Rate by the Air Seco Exchange Rate for the same sample.

Feasibility Test Candida albicans The Candida albicans Viability Test is a measure of the effect of absorbent garments, such as disposable diapers, on the viability of pathogenic microorganisms and in particular of Candida albicans. In general, the Feasibility Test of Candida albicans involves the inoculated sites of each palmar forearm of the test subjects with a suspension of albican Candida cells covering the sites with a full thickness patch from the absorbent garment, and determining the level of viability after a period of 24 hours.

A sample patch of thickness test complet having a length of 5 centimeters and a width of around 5 centimeters was cut off from the target area of each product that is to be tested. The target area is generally that part of the product intended to receive urine discharge from the user and typically includes portions of the intermediate and front waist sections of the product somewhat forward of the lateral centerline of the product. In a typical diaper configuration, the full thickness test sample diaper includes the top sheet, the absorbent body, the bottom sheet and any intervening layers. Approximately 15 milliliters of a salt water solution of 0.9 percent by weight were added. to the sample patch d test and allowed to soak in two minutes before the samples were placed on the forearms of the test subjects A 6.15 square centimeter test site area was marked on each of the palmar forearms of the test subjects. the subjects d test. About 0.01 milliliters of a 0.9 percent by weight salt water solution containing a suspension of Candida albicans cells was delivered to the test site with micropipettes and the suspension was then spread evenly through the test site. After air drying, the test site was covered with the test sample patch which was secured in position using the adhesive tape completely surrounding the sample.

After 24 hours, the test sample patches are removed and a quantitative culture is obtained from the test site using the detergent scouring method set forth in "A New Method for the Quantitative Investigation of Cutaneous Bacteria", by P. Williamson and A. M Klingman, Journal of Investigative Dermatology, 45: 498-503, 1965, the description of which is incorporated herein by reference. Briefly, a sterile glass cylinder spanning an area of 6, square centimeters was centered over the test site and was firmly held to the skin. One milliliter of 0.1 percent po weight of Triton-x-100 in a phosphate buffer of 0.075 having a pH of 7.9 was pipetted into a glass cylinder and the area was scrubbed for one minute using a rod of sterile Teflon. The fluid was aspirated with a sterile pipet and a second milliliter of 0.1 percent by weight d Triton-x-100 in phosphate buffer of 0.075 M having a p of 7.9 was added to the glass cylinder. The step d was repeated and the two washes stagnated. Each stagnant sample was diluted in ten-fold steps with 0.05 percent by weight of Triton-x-100 in a phosphate buffer of 0.037 having a pH of 7.9. An aliquot of 0.01 milliliter each dilution was inoculated onto Sabourands agar containing antibiotics. Duplicate cultures were prepared and incubated at room temperature for 48 hours.

After incubation, the number of colony forming units was counted using standard microbiological methods. The viability of Candida albicans under a patch d test specimen can then be compared to the viability of Candida albicans under a control patch from a conventional absorbent article having an outer covering if capable of breathing, eg, an outer covering having a rate of transmission of water vapor of less than 10 grams per square meter per 24 hours, such as the cloth described below in relation to Comparative Example 4.

The following examples are presented to provide a more detailed understanding of the invention. The specific materials and parameters are exemplary and are not intended to specifically limit the scope of the invention Examples Example 1 Disposable diapers having the same general construction as the HUGGIES® Supre Step 3 diapers described in relation to Comparative Example 2 given below were hand-made and tested. The diapers were essentially the same as the Supreme diapers except that the lower sheet, the absorbent core, the emergence layer and the elasticized diaper bands of the diapers were replaced or modified and a ventilation layer was added between the lower sheet and the core. absorbent In the tested diapers, the bottom sheet includes a nonwoven laminate / micropore film comprising a nonwoven material bonded with laminated yarn with a microporous film. The hilad bonded nonwoven comprised filaments of about 1.8 denier extruded from an ethylene copolymer with about 3.5 percent by weight of propylene and defined a basis weight of from about 2 grams per square meter. The film comprised a co-extruded film set having calcium carbonate particles there and defined a basis weight of about 58 grams per square meter before stretching. The film was preheated, stretched and tempered to form the micropores and then laminated to the spunbonded nonwoven material. The resulting microporous film / nonwoven laminate base material had a basis weight of 45 grams per square meter and a water vapor transmission rate of about 4,000 grams per square meter per 24 hours. Examples of film / non-woven laminate materials are described in greater detail in U.S. Patent Application No. 08 / 882,712 filed on June 25, 1997 under the name of McCormack et al. Entitled "SIZE FILMS". UNDER FILM / NON-WOVEN LAMINATES, whose description is incorporated herein by reference.

The absorbent core in the diapers tested f a dual layer absorbent having the generic configuration set forth in Figures 5 and 6 except that there were no orifices or openings through any layer of the absorbent. The absorbent core included a top layer and a bottom layer with the top layer extending from the front edge of the absorbent core to a location about two thirds of the total length of the absorbent core. The absorbent core included from about 10 to about 11 grams of wood pulp fibers and from about 10 to about 11 grams of superabsorbent material and, therefore, included about 50 weight percent pulp fibers. of mader and about 50 percent by weight of superabsorbent material. The bottom layer had a basis weight of about 230 grams per square meter and the top layer had a base pe at around 560 grams per square meter to provide a total basis weight of about 790 grams per square meter in the front section of the core and a basis weight around 230 grams per square meter in the lower section of the core. The absorbent core further defined a width in the crotch section of about 6.35 centimeters.

The emergence layer was localized between the absorbent core and the top sheet and it was from the same material as the emergence layer in the Supreme diapers described in Comparative Example 2 except that it was modified to be coextensive with the absorbent core. The diapers also included a ventilation layer between the absorbent core and the lower diaper sheet. The ventilation layer was made of the same material as the emergence layer and was also coextensive with the absorbent core. The diapers also included a elasticated leg band assembly along about two-thirds the length of each longitudinal side edge of the diaper. The assembly had six (6) threads of elastomeric material laminated to a non-woven fabric layer with the ability to breathe. The elastic yarns were composed of LYCRA® elastomer aligned along the longitudinal extension of the diaper to stretch and fold the leg bands of the diaper.

Four diaper samples were subjected to the Gas Tracker Test set above. The results are set forth in Table 1 given below.

Example 2 They were made by hand and disposable diapers were tested having the same general construction as that of the diapers described in relation to Example 1. The diapers were essentially the same as the diapers of Example 1, except that the absorbent body was modified to include a plurality of diapers. of s through it in the region where the top layer covered the bottom layer as illustrated in Figures 5 and 6. The s had a diameter of 1.2 centimeters to provide an open area of about 1 percent based over the total surface area of the absorbent body. Four samples of the diapers were subjected to the Gas Tracker Test set above. The results are set forth in Table 1 given below.

Example 3 Disposable diapers having the same general construction as the diapers described in relation to Example 2 were made by hand and tested. The diapers were essentially the same as the diapers of Example 2, except that the ventilation layer was removed between the absorbent body and the lower sheet. Four diaper samples were subjected to the tracer gas test established above. The results are set forth in Table 1 given below.

Example 4 Disposable diapers having the same general construction as the diapers described in relation to Example 2 were made by hand and tested. The diapers were essentially the same as the diapers of Example 2 except that the s in the absorbent body had a diameter of 2.54 centimeters which also defined an open area of about 12 percent of the total surface area of the absorbent body. Four samples of diapers were subjected to the Gas Tracker Test established above. The results are set forth in Table 1 given below.

Example 5 Disposable diapers having the same general construction as the diapers described in relation to Example 2 were made by hand and tested. The diapers were essentially the same as the diapers of Example 2 except that the absorbent body was replaced in layers with an absorbent body without layers which included about 62 percent by weight of wood pulp fibers and about 3 percent by weight. of superabsorbent and defined a basis weight e the frontal section of about 750 to 850 grams per square meter and a base weight in the posterior section of around d 375 to about 425 grams per square meter. Four samples of the diapers were submitted to the Gas Tracking Test stated above. The results are established in the Table given below.

Example 6 Disposable diapers having the same general construction as the diapers described in relation to Example 2 were made by hand and tested. The diapers were essentially the same as the diapers of Example 2 except that the dual layer absorbent core was replaced with a laminate which included about 80 percent by weight of commercially available superabsorbent material from Stockhausen under the trade designation FAVOR SXM 88 overwrapped by a tissue layer of cellulosic fibers having a basis weight of about 26 grams per square meter. The absorbent body also included openings therethrough having a diameter of 1.27 centimeters to provide an open area of about 12 percent of the total surface area of the absorbent body. Four diaper samples were submitted to the Gas Tracker Test set above. The results are set forth in Table 1 given below.

Example 7 Disposable diapers having the same general construction as the diapers described in relation to Example 2 were made by hand and tested. The diapers were essentially the same as the diapers of Example 2 except that the absorbent body was replaced with a laminate which included 80 percent by weight of superabsorbent material commercially available from Stockhausen under the trade designation FAVOR SXM 880 overwrapped by a tissue cap of cellulosic fibers which have a base weight d around 26 grams per square meter. The laminate was provided in four segments as shown representatively in Figures 3 and 4 which resulted in an opening for the absorbent body of about 40 percent of a total surface area of the absorbent body. S submitted four samples of the diapers to the Gauge Tracker Test established above. The results are set forth in Table 1 given below.

Example 8 Disposable diapers having the general construction of the diapers described in relation to Example 2 were made by hand and tested. The diapers were essentially the same as the diapers of Example 2 except that the bottom sheet was modified to define a water vapor transmission rates of about 1870 grams per square meter per 24 hours. Four diaper samples were submitted to the Gas Tracker Test set forth above. The results are set forth in Table 1 given below.

Comparative Example 1 Disposable diapers having the same general construction as that of the Supreme Step 3 diapers as described in connection with Example 2 were made by hand and tested. The diapers were essentially the same as the diapers of Example 2, except that the bottom sheet was replaced with a thousandth of an inch thick polyethylene film material having a water vapor transmission rate of less than 100 grams per square meter. by hour Four samples of the diapers were submitted to the Gas Tracker Test established above. The results are set forth in Table 1 given below.

Comparative Example 2 Disposable diapers having the same general construction as that of commercially available diapers from Kimberly-Clark Corporation under the trade designation HUGGIES® Supreme Step 3 were tested.

In essence, the Supreme diapers composed of an absorbent core consisting of a mixture of wood pulp fibers and superabsorbent material surrounded by a two-piece cellulose wrap d having a basis weight d around 16-21 grams per square meter. The absorbent core included from about 12.5 to about 13 grams of wood pulp fibers placed by air and from about 7.0 to about 8.5 grams of superabsorbent material. The superabsorbent material was purchased from Stockhausen under the trade designation FAVOR SXM 880. The superabsorbent material was homogenously mixed with the pupal fibers to form a unitary layer having a density within the range of 0.25 to 0.35 grams per cubic centimeter. . The homogenous mixture of the superabsorbent material and the wood pulp fibers was zoned along the machine direction to provide a basis weight of from about 600 to about 700 grams per square meter in the front section of the absorbent core. and a base weight of from about 300 to about 350 grams per square meter the back section of the absorbent core.

The Supreme diapers also included a composite lower ho comprising a permeable vapor barrier layer adhesively laminated to a spunbonded / meltblown / spunbonded (hereinafter "SMS") laminate. The spunbonded / meltblown / spunbonded bonded laminate had a basis weight of about grams per square meter. The vap-permeable barrier layer consisted of a polyolefin film which had a thickness of 0.7 mils and a basis weight of about 19 grams per square meter. The polyolefin film material was commercially available from Exxon Chemic Patents Incorporated under the trademark EXXAIRE. The vapor-permeable barre layer was adhered to the SMS laminate and placed between the absorbent core and the SMS laminate of the lower blade. The lower sheet had a water vap transmission rate of around 1,500 grams per square meter per hour. The absorbent core was placed in the form of a sandwich between the lower sheet and the upper sheet composed of a woven fabric bonded with polypropylene fiber yarn having a basis weight of about 17 grams per square meter. An emergence management layer composed of a bonded and carded fabric is located between the topsheet and the absorbent core. The emergence layer included bicomponent fibers and defined a global bas weight of around 83 grams per square meter. The emerg layer was a homogeneous mixture composed of about 6 percent by weight of bicomponent sheath-core d polyethylene / polyester (PE / PET) fibers which had a denier d fiber of about 3 d and about 40 db. percent per pes of single-component polyester fibers which had a fiber denier of about 6 d and which had fiber lengths of from about 3, 8 to around 5.0 centimeters. The emergence layer also defined a width d around 10.2 and a length of about 16, centimeters. The front edge of the emergence layer was located 5.1 centimeters from the front edge of the absorbent core The Supreme diapers also included a single-component elasticated waistband and waistband conjunct at each longitudinal end of the diaper. The assembly had multiple yarn of elastomeric material placed in sandwich form and laminated between a layer of polymer film and a layer of non-woven fabric. The polymer film had a 0.00075 inch thick film composed of a mixture of linear low density polyethylene and ultra low density polyethylene. The non-woven fabric layer consisted of a fabric of 20 grams per square meter of bonded polypropylene yarn. The elastic threads were composed of 8-16 LYCRA® elastomer yarns aligned along the transverse direction of the diaper to stretch and fold the waistband of the diaper and the inner waist flaps. The Supreme diapers also included the containment flaps in the diaper. longitudinal sense which extend the full length of the diaper and elasticized leg bands along the longitudinal side edge of the diaper. The elastic threads in the leg band and the containment fins were composed of the LYCRA® elastomer aligned along the longitudinal length of the diaper to stretch and collect the diaper leg bands and the containment fins.

Four samples of the diapers were submitted to the Gas Tracker Test as stated above. The results are set forth in Table 1 given below.

Table 1 Exchange Rate Dry Air Exchange Rate Humid Air Medium Ratio (cmVmin) Medium (cm3 / min) Wet / Dry Example 1 822 224 0.27 Example 2 794 310 0.39 Example 3 679 220 0.32 Example 4 1050 360 0.34 Example 5 758 190 0.25 Example 6 724 240 0.33 Example 7 677 153 0.23 Example 8 495 316 0.63 Ex. Comparative 1 51 110 2.16 Ex. Comparative 2 513 171 0.33 The test results of Examples 1-8 and Comparative Examples 1-2 indicate that the diapers made in accordance with the present invention generally have improved levels of air exchange both when they are dry and as a result thereof. when they are wet compared to conventional diapers Example 9 Four diaper samples having the same general construction as that of the diapers described in relation to Example 2 were made by hand and tested according to Skin Hydration Test established above. The pampers were essentially the same as the diapers of the Example except that the diapers were similar in size to the commercially available size Step 4 diapers, the absorbent body was a single layer having the same thickness, and the openings had a diameter of 2. 54 centimeters The diapers "They defined an average Skin Hydration Value of 8.1 grams per square meter per hour." The results are also set forth in Table 2 given below.

Example 10 Four diaper samples having the same general construction as the diapers described in relation to Example 6 were made by hand and tested according to Skin Hydration Test established above. The diapers were essentially the same as the diapers of the Example except that the diapers were similar in size to the commercially available size diapers of Step 4, the absorbent body defined a basis weight of about 560 grams per square meter and the openings had a diameter 2.5 centimeters. The diapers defined an average skin moisture value of 2.8 grams per square meter per hour. The results are also established in Table 2 given below.

Example 11 Four diaper samples having the same general construction as that of the diapers described in relation to Example 7 were made by hand and tested according to the Skin Hydration Test set above. The diapers were essentially the same as the diapers of Example 7 except that the diapers were similar in size to the commercially available Step 4 diapers. The diapers defined a Skin Hydration Value of 1.6 grams per square meter per hour. The results are also set forth in Table 2 given below.

Comparative Example 3 Disposable diapers were tested having the same general construction as those commercially available diapers from Kimberly-Clark Corporation under the HUGGIES® Supreme brand. Step 4. In essence, Supreme Pas-sized diapers were similar to Supreme Step size diapers described above in relation to Comparative Example 2 except that the size of the materials was greater.

Four samples of the diapers were submitted to the Skin Hydration Test set forth above. The diapers defined an average Skin Hydration Value of 19.3 grams per square meter per hour. The results are set forth in Table 2 given below.

Table 2 Skin Hydration Value (g / m2 / hour) Example 9 8.1 Example 10 2 .8 Example 11 1.6 Comparative Example 3 19.3 The test results of Examples 9-11 and Comparative Example 3 indicate that diapers made according to the teachings of the present invention exhibit significantly improved Skin Hydration Values when compared to conventional diapers. Specifically, diapers made in accordance with the present invention exhibited a 58 to 92 percent reduction in Skin Hydration Value. Even though some reduction in the Skin Hydration Value was anticipated due to the increased amount of air exchange within the diapers, the magnitude of the reduction was unexpected.

Example 12 Diaper samples were made and tested which have the same general construction as the diapers described in relation to Comparative Example 2. The diapers were essentially the same as the diapers of Comparative Example 2 except that the lower sheet was modified to define a of water vapor transmission of around 3,000 grams per square meter per 24 hours. The diapers were submitted to the Candida albicans Viability Test established above. The samples of Example 13 and Comparative Example 4 (control) were tested on the palmar forearms of each of seven test subjects. Approximately 0.01 milliliters of a 0.9 percent by weight salt solution containing a suspension of 5.71 log colony forming units of Candida albicans was delivered to the test site with micropipettes and the suspension was then evenly spread. through the test site. The sample diapers according to this example defined a viability of Candida albicans of 1.96 log of colony forming units of Candida albicans. Therefore, in comparison to the viability of Candida albicans control medium (Comparative Example 4), the diapers according to this example defined a reduction in the viability value of Candida albicans of 26 percent.

Example 13 Samples of diapers were made having the same general construction as the diapers described in relation to Example 2, except that the bottom sheet defines a water vapor transmission rate of about 5,000 grams per square meter per 24 hours. The diapers were subjected to the Candida albicans Viability Test established above. The samples of Example 13 and Comparative Example 4 (control) were tested on the palmar forearms of each of seven test subjects. Approximately 0.01 milliliters of a 0.9 percent by weight salt solution containing a suspension of 5.71 log colony forming units of Candida albicans was delivered to the test site with micropipette and the suspension was then uniformly spread. through test site. It was anticipated that the sample diapers according to this example would define a viability of Candid albicans half of feasibly less than 1.75 and feasibly less than 1.50 log colony forming units of Candid albicans. Therefore, in comparison to the viability of Candid albicans control medium (Comparative Example 4), it is anticipated that the diapers according to this example will define a reduction in the viability value of Candida albicans of more than about 34% and feasibly d about 43 percent.

Comparative Example 4 The diaper samples having the same general construction as the diapers described in relation to Comparative Example 2 were made and tested. The diapers were essentially the same as those of Comparative Example 2, except that the bottom sheet was replaced with a 1.0 mil polyethylene film material having a water vapor transmission rate of less than 100 grams. per square meter per 24 hours. The diapers were subjected to the Candida albicans Viability Test established above on the palmar forearms of each of the seven test subjects. Approximately 0.01 milliliters of a 0.9 percent by weight salt solution containing a 5.71 log suspension of colony forming units of Candida albicans was delivered to the test site with micropipettes and the suspension was then uniformly spread. through the test site. The sample diapers according to this example defined a viability of Candida albicans of 2.65 log of colony forming units of Candi da albi cans.

Example 14 The diaper samples having the same general construction as the diapers described in connection with Example 13 were machine-made and tested. In particular, the lower sheet of the diapers defined a water vapor transmission rate of around 5,000 grams per square meter per 24 hours. The diapers were subjected to the Candida albicans Viability Test established above. The samples of Example 14 and Comparative Example 5 (control) were tested on the palmar forearms of each of the twenty test subjects. Approximately 0.01 millimeters of a saline solution of 0.9 percent by weight containing a 4.92 log suspension of colony forming units of Candida albicans was delivered to the test site with micropipettes and the suspension was then uniformly spread to through the test site. The sample diapers according to this example defined a viability of Candida albicans of 1.26 log d colony forming units of Candida albicans. Therefore in comparison to the viability of Candida albicans control medium (Comparative Example 5), the diapers according to this example defined a reduction in the viability value of Candida albicans of 61 percent.

Comparative Example 5 Samples of the diapers having the same general construction as that of the diapers described in Comparative Example 4 were machine-made and tested. In particular, the bottom sheet of the diapers included a polyethylene film material of 1.0. thousandths of an inch thick having a water vapor transmission rate of less than 100 grams per square meter per 24 hours. The diapers were subjected to the albican Candida Viability Test established above on the palmar forearms of each of the twenty test subjects. Approximately 0.01 milliliters of a 0.9 percent salt water solution per pound containing a 4.92 log suspension of colony forming units of Candida albicans was delivered to the test site with micropipettes and the suspension was then uniformly spread. through the test site. The samples of diapers according to this example defined a viability of Candida albican average of 3.26 log colony forming units of Candid albicans.

The test results of Examples 12 and 14 the expected results of Example 13 show that diapers made according to the present invention exhibit reduced viability and an incidence of microbial infection when compared to conventional absorbent diapers and test results. of Comparative Examples 4 and 5. It is clear that such reduced microbial viability was achieved by reducing the occlusion of the skin by increasing the capacity to breathe of the diaper both when it is dry and when it is wet.

Having thus described the invention in considerable detail, it will be readily apparent to a person of ordinary skill that various modifications may be made without departing from the spirit of the invention. All such changes and modifications are contemplated as being within the scope of the present invention as defined by the attached clauses.

Claims

E V I N D I C A C O N E S

1. A disposable absorbent article q comprises an absorbent, a front waist section, or a posterior waist section and an intermediate section the interconnecting said front and back waist sections where said absorbent article defines a viability of Candi albicans which is less than about of 85 percent of the viability of Candida albicans from a control calculated according to the Feasibility Test of Candida albicans as established here.

2. The absorbent article as claimed in clause 1, characterized in that the viability of Candida albicans is less than about 80 percent of the viability of Candida albicans from the control calculated according to said Viability Test of Candida albicans.

3 . The absorbent article as claimed in clause 1, characterized in that the viability of Candida albicans is less than about 60 percent of the viability of Candida albicans from the control calculated according to said Viability Test of Candida albicans.

. The absorbent article as claimed in clause 1, characterized in that said absorbent article defines a Wet Air Exchange Rate of at least about 190 cubic centimeters per minut calculated according to the Gas Tracker Test as It's established here.

5. The absorbent article as claimed in clause 1, characterized in that said absorbent article defines a Dry Air Exchange Rate of at least about 525 cubic centimeters per minut calculated according to the Gas Tracker Test as It's established here.

6. The absorbent article as claimed in clause 1, characterized in that said absorbent article defines a Skin Hydration Value of less than about 18 grams per square meter per hour calculated according to the Skin Hydration Test as It's established here.

7. A disposable absorbent article which comprises: a) a lower vapor permeable sheet defines a Water Vapor Transmission Rate of at least about 1,000 grams per square meter per 24 hour calculated according to the Ag Steam Transmission Test as set forth herein; b) a liquid-permeable upper sheet which is placed in a frontal relationship with said lower sheet; c) an absorbent body located between said lower sheet and said upper sheet wherein said absorbent article defines a viability of Candida albicans which is less than about 85 percent of the viability of Candid albicans of a control calculated according to the Test d Viability of Candida albicans as established here.

8. The absorbent article as claimed in clause 7, characterized in that the viability of Candida albicans is less than about 80 percent of the viability of Candida albicans of the control calculated according to said Viability Test of Candida albicans.

9. The absorbent article as claimed in clause 7, characterized in that the viability of Candida albicans is less than about 60 percent of the viability of Candida albicans of the control calculated according to said Viability Test of Candida albicans.

10. The absorbent article as claimed in clause 7, characterized in that said absorbent article further defines a Humid Air Exchange Rate of at least about 190 cubic centimeters per minute calculated according to the Gas Tracker Test as It is established here.

11. The absorbent article as claimed in clause 7, characterized in that said absorbent article defines a Dry Air Exchange Rate of at least about 525 cubic centimeters per minut calculated according to the Gas Tracker Test as It's established here.

12. The absorbent article as claimed in clause 7, characterized in that said absorbent article defines a Skin Hydration Value of less than about 18 grams per square meter per hour calculated according to the Skin Hydration Test set forth herein.

13. The absorbent article as claimed in clause 7, characterized in that said lower vapor-permeable leaf is essentially impermeable to liquid.

14. The absorbent article as claimed in clause 7, characterized in that said lower vapor-permeable leaf defines a Hydro head value of at least about 60 centimeters calculated according to a Hydrostatic Pressure Test as set forth herein.

15. The absorbent article as claimed in clause 15, characterized in that said Water Vapor Transmission Rate of said lower vapor permeable sheet is of at least 1,500 grams per square meter per 24 hours calculated according to the Test of Water Vapor Transmission.

16. A disposable absorbent article defines a front waist section, a back waist section, and an intermediate section which interconnects said front and back waist sections, said absorbent article comprising: a) a lower vapor permeable sheet which defines a Water Vapor Transmission Rate of at least about 1,000 grams per square meter per 24 hours calculated according to the Water Vapor Transmission Test as set forth herein; b) a liquid-permeable upper sheet which is placed in a frontal relationship with said lower sheet; c) an absorbent body located between said lower sheet and said upper sheet which defines zones of high air permeability for improved air exchange; Y d) a layer of ventilation located between said lower sheet and said absorbent body wherein said absorbent article defines a viability of Candida albicans which is less than about 85 percent of the viability of Candid albicans of a control calculated according to the Test d Viability of Candida albicans as established here.

17. The absorbent article as claimed in clause 16, characterized in that said lower leaf permeable to water vapor is essentially liquid impervious.

18. The absorbent article as claimed in clause 16, characterized in that said Water Vapor Transmission Rate of said lower vapor permeable sheet is at least about 1,500 grams per square meter per 24 hours calculated according to the Water Vapor Transmission Test.

19. The absorbent article as claimed in clause 16, characterized in that said high air permeability zone in said absorbent body defines a Frazier Porosity which is at least about 10 percent greater than a Frazier Porosity of parts of said absorbent body adjacent to said air passages.

20. The absorbent article as claimed in clause 16, characterized in that said high air permeability zone comprises from about to about 75 percent of a total surface area d said absorbent body.

21. The absorbent article as claimed in clause 16, characterized in that the viability of Candida albicans is less than about 80 percent of the viability of Candida albicans from the control calculated according to said Viability Test of Candida albicans.

22. The absorbent article as claimed in clause 16, characterized in that said absorbent article further defines a Wet Air Exchange Rate of at least about 190 cubic centimeters per minute calculated according to a Gas Tracker Test such and as stated here.

23. The absorbent article as claimed in clause 16, characterized in that said absorbent article defines a Skin Hydration Value of less than about 18 grams per square meter per hour calculated according to the Skin Hydration Test set forth herein.

24. The absorbent article as claimed in clause 16, characterized in that said ventilation layer comprises a hydrophobic nonwoven material having a thickness of at least about 0.10 centimeters and a basis weight of from about 20 to about of 120 grams per square meter.

25. The absorbent article as claimed in clause 16, characterized in that it further comprises an emergence management layer which is located between said top sheet and said absorbent wherein said emergence handling cap comprises a non-woven material having a base weight from about 30 to about 12 grams per square meter. SUMMARY An absorbent article includes a vapor permeable lower sheet, a liquid permeable upper sheet placed in a front relation with the lower sheet; and an absorbent body located between the lower sheet and the upper sheet which define multiple zones of high air permeability. The absorbent article may also include a ventilation cap between the absorbent body and the lower sheet an emergence management layer between the absorbent body and the top sheet. The article exhibits improved air exchange within the article during use. As a result, the article essentially exhibits reduced levels of hydration of the user's skin when in use which makes the skin less susceptible to the viability of microorganisms.