MXPA01009160A - Sanitary pad for variable flow management - Google Patents

Abstract

There is provided a feminine hygiene pad comprising a cover adjacent a capillarity fabric having regions of high and low capillarity, which is adjacent a retention layer. In a preferred embodiment, a creped spunbond layer is used as the cover material and a co-apertured intake/distribution layer and transfer delay layer are the capillarity fabric. Combining these improvements into an integrated absorbent system allows the successful achievement of variable flow management and a successful balance between intake and cover desorption properties. The result is improved multiple intake performance and a clean and dry cover surface during use.

Description

SANITARY PILLOW FOR A VARIABLE FLOW HANDLING This application claims priority of the provisional patent application of the United States of America number 60 / 127,685 filed on April 3, 1999.

FIELD OF THE INVENTION The present invention relates to an absorbent article for personal care, particularly to products for the hygiene of women, which can accept liquids, distribute them and retain them.

BACKGROUND OF THE INVENTION Personal care items include such items as diapers, training underpants, women's hygiene products such as sanitary napkins, pant liners and plugs, garments and incontinence devices, bandages and the like. The most basic design of such articles typically includes a side-to-body liner, an outer cover (also referred to as a spacer) and an absorbent core positioned between the body-side liner and the outer cover.

Personal care products must accept fluids quickly and retain them to reduce the possibility of runoff from the product. The product should be flexible and should have a pleasant sensation on the skin, even after the discharge of liquid, and should not be made tight or signal to the user. Unfortunately, even though previous products have satisfied many of these criteria to varying degrees, a large number have not.

In particular, products for women's hygiene for long-term use (eg night) are subjected to flow rates and fluid loads higher and more variable than those intended for regular or shorter-term use. The products for night use, therefore, must have the capacity to absorb and contain a continuous and light flow as well as a sudden heavy flow and bubbles during the life of the product. It has been found that the continuous flow discharges in women's hygiene products average one ml / hour, but they may be higher and are not literally continuous or constant but rather variable in the rate and may still have a pause "during a cycle. The "extreme flow" is defined as a sudden heavy flow condition that occurs at flow rates of up to 1 ml / second. During a gurgling, 1 milliliter to 5 milliliters of fluid are released from the body to the product. The term "continuous flow" is used to define any flow which falls outside the definition of extreme flow.

Combining the conditions of extreme flow and continuous i results in a variable flow. Essentially, a "variable flow" is defined as a continuous flow with occurrences of intermittent extreme flow. Figure 1 is a graph which illustrates the differences between variable flow (diamonds) and continuous flow (tables) over the life of a single product where the volume of flow rate is on the y-axis in g / hours and the time is on the x axis in hours. This problem of managing extreme and continuous flows is called variable flow management and is defined as the ability to absorb and contain a light and continuous flow (1-2 ml / hour) as well as multiple sudden or extreme heavy flow discharges. (1 ml / second with a total volume of 1 milliliter-5 milliliters) over the life of the product. It is obvious that the challenge of variable flow management is more difficult when the time of use of the product is extended, such as the conditions of night use.

Many cover materials for women's care have a z-direction conduction, a low surface energy, a low hollow volume, and provide a small separation between the absorbent core and the user due to their two-dimensional structure. Consequently, these covers result in a slow and incomplete absorption, in a superior re-wetting, and in large surface spots.

In addition, the typical absorption or acquisition layers are low density, high void volume structures which are ideal for rapid fluid absorption, but because these structures typically have low capillary action, the fluid is not properly desorbed from the surface. roofing material, resulting in mud and surface moisture.

The materials which increase the roof desorption are typically high density and high capillary materials, but because these materials have a low hollow volume and a low permeability in the z-direction, they inherently retard the absorption of the material. fluid.

There is still a need to refer to the management of variable flow from the point of view of the global product form, developing a system in which the components are optimized to work together. In such a system, the liner is designed to promote rapid absorption and remain clean and dry, there is an absorption / distribution material which has the necessary hollow volume for rapid absorption and the high wicking desired for a sufficient roof desorption while an appropriate capillary structure is maintained for fluid distribution / intake and the absorbent (retention) layer accepts the fluids at the appropriate speed.

An objective of this invention is therefore to provide a comprehensive design for a product for women's hygiene, particularly for night use, to handle a wide variety of flow conditions including sudden heavy flow discharges, or gushes.

SYNTHESIS OF THE INVENTION The objects of the invention are achieved by a non-woven fabric bonded with yarn and crepe to be used as the liner or outer cover, an improved absorbent core employing an air-laid and co-punched fabric layer and a transfer delay layer of non-woven fabric bonded with yarn, on a lint retention layer. Combining these improvements in an integrated absorbent system allows the successful achievement of variable flow management and a successful balance between the properties of absorption and desorption of the roof. The result is an improved multiple absorption operation and a dry and clean cover surface during use. Material technology developments in relation to variable flow management are focused on achieving the proper material structure and the appropriate balance needed to achieve rapid absorption and improve roof desorption, roof staining and rewet characteristics. These functional properties are provided through improved material technologies and product construction.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a graph of a variable flow (diamonds) and continuous flow (tables) over the life of a single product where the volume of flow rate is about the y-axis in g / hour and the time is over the x-axis in hours.

Figure 2 illustrates the trimodal pore structure of the coperforated material.

Figures 3, 4 and 5 show the SEM images of the openings. Figure 3 shows an opening on the side placed by air of the compound. Figure 4 shows an approach of an opening on the air-laid side of the compound and Figure 5 shows an apparatus from the spin-linked side (transfer delay) of the compound.

Figure 6 compares the pore size distribution of a material placed by air and perforated with a material placed by non-perforated air.

Figure 7 illustrates the detail of a single opening i and flow through the material. Figure 8 is a graph of the pore size distribution for creped and non-creped yarn bonded cover materials.

Figure 9 shows the three-dimensional structure of the fabric cover bonded with yarn creped in an SEM image.

Figure 10 shows an example of a product form for a feminine hygiene product for night use.

Figure 11 illustrates the theoretical fluid loading profile for the women's hygiene product of Figure 10.

Figure 1? shows a bolt drilling pattern at 7.4 bolts / square centimeter using 2.06 mm diameter bolts.

Figure 13 shows a bolt hole pattern at 2.5 bolts / square centimeter with the same bolt diameter as in Figure 12.

Figure 14 is a graph of the measured capacity for fabrics placed by air and without openings where the capacity i is on the Y axis and the fabric density (cc / g) on the X-axis.

Figure 15 is a graph of the horizontal transmission distance (y-axis) in millimeters versus time in minutes for two perforated and two unperforated air-laid fabrics.

Figure 16 is a saturation graph in g / g (Y-axis) against the horizontal transmission distance in inches. i Figure 17 is a saturation graph in g / g (Y-axis) against the pad section as it is divided according to the flat system fluid distribution test.

Figure 18 is a saturation graph in g / g (Y-axis) against the pad section as divided according to the flat system fluid distribution test.

Figures 19, 20 and 21 are bar charts of triple extreme discharge results on various parts of a pad. DEFINITIONS "Disposable" includes being discarded after use and not intended to be washed or reused.

"Layer" when used in the singular may have the dual meaning of a single element or a plurality of elements.

"Liquid" means a substance not in particles and / or a material that flows and that can assume the interior shape of a container into which it is poured or placed.

"Liquid communication" means that the liquid is capable of moving from one layer to another layer, or from one place to another within a layer.

"Longitudinal" means having the longitudinal axis in the plane of the article and is generally parallel to a vertical plane that divides a user standing in the left and right body halves when the item is used. The "transverse" axis lies in the plane of the article generally perpendicular to the longitudinal axis, for example, so that a vertical plane divides a user standing in the front and back body halves when the article is used.

The phrase "conjugated fibers" refers to fibers that have been formed from at least two extruded polymers from separate extruders but which have been spun together to form a fiber. Conjugated fibers are sometimes referred to as multicomponent or bicomponent fibers. The polymers are usually different from one another even though the conjugated fibers can be monocomponent fibers. The polymers are arranged in different zones placed essentially constant across the cross section of the conjugated fibers and extend continuously along the length of the conjugated fibers. The configuration of such a conjugate fiber can be, for example, a sheath / core arrangement in i where one polymer is surrounded by another or it can be a side-by-side arrangement, a cake arrangement or an arrangement of "islands in the sea". " The conjugated fibers are shown in the patents of the United States of America numbers 5,108,820 granted to Kaneko and others, 5,336,552 granted to Strack and others, and 5,382,400 granted to Pike and others. For the two component fibers, the polymers may be present in proportions of 75/25, 50/50, 25/75 or any other desired proportions. The fibers may also have shapes such as those described in U.S. Patent Nos. 5,277,976 to Hogle et al .; and 5,069,970 and 5,057,368 granted to Largman et al., Incorporated herein by reference in their entirety, which describe fibers with non-conventional shapes.

"Biconstituent fibers" refer to fibers that have been formed from at least two polymers extruded from the same extruder as a mixture. The biconstituent fibers do not have the various polymer components arranged in relatively constant zones across the cross-sectional area of the fiber and the various polymers are usually non-continuous throughout the entire length of the fiber., instead of this usually forming fibrils or protofibrils which start and end at random. The biconstituent fibers are sometimes also referred to as multi-constituent fibers. Fibers of this general type are discussed in, for example, U.S. Patent No. 5,108,827 issued to Gessner. Bicomponent and biconstituent fibers are also discussed in the textbook Mixtures and Polymer Compounds by John A.

Manson and Leslie H. Sperling, copyright by Plenum Press, a division of Plenum Publishing Corporation of New York, IBSN 0-306-30831-2, pages 273 to 277. i As used herein, the term "machine direction" or MD means the length of a fabric in the direction in which it is produced. The term "cross machine direction" or CD means the width of the fabric, for example an address generally perpendicular to the machine direction.

As used herein the term "spunbond fibers" refers to small diameter fibers which are formed by extruding the molten thermoplastic material as filaments from a plurality of usually circular fine capillary vessels, of a spinner organ with the diameter of the fibers. extruded filaments then being rapidly reduced as indicated, for example, in U.S. Patent Nos. 4,340,563 issued to Appel et al., and 3,692,618 issued to Dorschner et al., 3,802,817 granted to Matsuki et al., 3,338,992 and 3,341,394 granted. to Kinney, 3,502,763 granted to Hartman, and 3,542,615 granted to Dobo and others. Spunbonded fibers are not generally sticky when they are deposited on a collecting surface. Spunbonded fibers are generally continuous and have average diameters (from a sample of at least 10) larger than 7 microns, more particularly, between 10 microns and 35 microns. The fibers may also have shapes such as those described in U.S. Patent Nos. 5,277,976 to Hogle et al., 5,466,410 issued to Hills and 5,069,970 and 5,057,368 to Largman et al., Which describe fibers with unconventional shapes.

As used herein, the term "meltblown fibers" means fibers formed by extruding a molten thermoplastic material through a plurality of thin, usually circular, capillary matrix vessels, such as melted filaments or filaments into gas streams. (for example air), usually hot and at high speed and converging which attenuate the filaments of the molten thermoplastic material to reduce its diameter, which may be a microfiber diameter. Then, the melt blown fibers are carried by the high velocity gas stream and are deposited on a recollecting surface to form a meltblown and randomly dispersed fiber fabric. Such a process is described, for example, in US Pat. No. 3,849,241 issued to Butin et al. Melt-blown fibers are microfibers that can be continuous or discontinuous, are generally smaller than 10 microns in average diameter, and are generally sticky when deposited on the collector surface.

"Air placement" is a well-known process by which a fibrous non-woven layer can be formed. In the process of placing by air, bunches of small fibers having typical lengths ranging from about 3 to about 52 millimeters are separated and carried in an air supply and then deposited on a forming grid, usually With the help of a vacuum supply, the randomly deposited fibers are then bonded to each other using, for example, hot air or sprayed adhesive.Examples of air-laying technology can be found in the patents of the United States. United of America numbers 4,494,278, 5,527,171, 3,375,448 and 4,640,810.

As used herein, the term "coform" means a process in which at least one meltblown die head is arranged near a conduit through which other materials are added to the fabric while it is being formed. Such other materials can be pulp, superabsorbent or other particles, fibers of natural polymers (for example rayon or cotton fibers) and / or of synthetic polymers (for example of polypropylene or polyester), for example, wherein the fibers can be of basic length. The coform processes are shown in the patents of the United States of America numbers 4,818,464 granted to Lau and 4,100,324 granted to Anderson and others and assigned in common form. The tissues produced by the coform process are generally mentioned as coform materials.

The phrase "carded and bound fabric" refers to fabrics that are made of basic fibers and are sent through a combing or carding unit, which opens and aligns the basic fibers in the machine direction to form a fibrous nonwoven fabric generally oriented in the machine direction. The tissue is joined by one or more of several known joining methods.

The bonding of the non-woven fabrics can be achieved by a number of methods; bonding with powder, wherein a powder adhesive is distributed through the fabric and then activated, usually by heating the fabric and the adhesive with hot air; pattern bonding, where heated calendering rolls or ultrasonic bonding equipment are used to join the fibers together, usually in a localized bonding pattern, even when the fabric can be bonded across its entire surface if it is desired; the union through air, where the air which; is hot enough to soften at least one component of the tissue is directed through the tissue; chemical bonding using, for example, latex adhesives that are deposited on the fabric by means of for example spraying; and consolidation by mechanical means such as drilling and hydroentanglement.

An absorption / distribution layer is a material which can transmit menstrual fluid from a distance of 1.2 centimeters to around 15.25 centimeters (0.5 inches to 6 inches) in an hour when one end of the material is placed in a reservoir, infinite menstrual fluid simulator.

"Coverage" refers to a material that has been drilled, as well as a drilling process, where two or more materials are drilled together. The openings extend from the upper part to the lower part of the material and are essentially aligned with each other. The coperforation can unite the materials, either temporarily or permanently, through the entanglement, the physical union or the chemical union. It is preferred that the coperforation be carried out at room temperature and not at elevated temperatures.

A "personal care product" means diapers, underpants, absorbent undergarments, adult incontinence products, swimwear, bandages and other bandages for wounds, and products for women's hygiene.

"Products for women's hygiene" means t sanitary pads and pads.

The "target area" refers to the area or position on a personal care product where a discharge is normally delivered by a user.

TEST METHODS Material Caliber (Thickness): The caliber of a material is a measure of thickness and is measured at 0.05 pounds per square inch (3.5 grams / square centimeter) with a Starret type volume tester, in units of millimeters.

Density! The density of the materials was calculated by dividing the weight per unit area of a sample in grams per square meter (gsm) by the material gauge in millimeters (mm) to 0.05 pounds per square inch (3.5 grams / square centimeter) and multiplying the result by 0.001 to convert the value to grams per cubic centimeter (g / cc). A total of three samples will be evaluated and averaged for the density values.

Triple Test Procedure: The objective of this test is to determine the differences between the materials and / or materials, compounds or systems of material compounds in the absorption rate when three insults of fluid are applied, with a time allowed for the fluid to be distributed in the material or materials between downloads.

Required equipment: 2 acrylic rate blocks.

Pipette P-5000 with RC-5000 tips and a foam pipette insert.

Small weighted glass.

Menstrual fluid simulator (done according to the instructions given below), warmed in a bath for 30 minutes or more. i Small spatula (shaker) F Banking lining 2 Chronometers 1-2 watches Gaza squares to clean simulator.

Procedure: Place the sample compounds according to the material testing plan.

The components are as follows: Superior: Cover.

Medium: Capillarity fabric.

Bottom: Retention layer: Weigh each dry layer, record the weight. Put the materials back into the three-layer composite. Weigh a dry secant, record the weight and also mark the weight on the secant. Place block of acrylic rate in the middle part of the sample compound.

Calibrate the pipette: Weigh a small empty beaker on the scale. i Put the pipette at 2 mis.

Pull the simulator inside the pipette.

Deliver the simulator from the pipette to the picudo glass.

If the balance indicates that 2 grams of simulator were delivered, the placement is correct.

If they were delivered more or less than 2 grams, decrease or increase the placement and repeat by adjusting the pipette and weighing the amount of simulator delivered until 2 grams are delivered.

Simulator management: Remove the refrigerator simulator 30 minutes to 1 hour before use and warm a water bath. Before cutting the bag nozzle, massage the bag between your hands for a few minutes to mix the simulator, which will be separated in the bag. Cut the bag tube and pour the necessary simulator into the small beaker. Shake slowly with a small spatula to mix thoroughly. Return the refrigerator bag if you do not anticipate using everything. Return the bag to the water bath if it will be used more during the day.

Proof : Step 1: Center the acrylic rate block with funnel on the sample. Insult the sample compound with 2 simulators, using the timer to measure the time from the beginning of the insult until the fluid is absorbed under the cover material. Leave the rate block in place for 9 minutes (use the clock). For the first sample, after 9 minutes remove the rate block and weigh each layer of the sample. Record the weight (after 3 minutes measure the time of the first sample, start testing a second sample that goes through the same steps).

Step 2: For the first sample, repeat step 1 a second time.

Step 3: For the first sample, repeat step 1 a third time.

Analysis: The fluid loading in each component was calculated as weight after the insult subtracted from the weight before the insult. Insult time is a direct measurement of the time for absorption. The small values of absorption time refer to more sample of absorbent with the larger values of absorption time referring to a less absorbent sample.

Capacity The capacity was measured using the soak and drip capacity test method. Menstrual fluid simulators were used as the test fluid. The size of the sample was modified to a circle of 5.7 centimeters in diameter (2.25 inches). The weight of each sample was recorded. The sample was immersed in a simulator bath until equilibrium, in this case 9 minutes. The sample was removed from the bath and hung vertically to a height of 10.5 centimeters (12 inches) using a small bra for 10 minutes. The sample was weighed and the weight was recorded. The capacity was determined by subtracting the previous weight from the subsequent weight. The capacity in grams / gram was determined by dividing the capacity in grams of the dry weight of the sample. í Horizontal Capillary Transmission Test Procedure; The objective of this test is to determine the horizontal transmission capacity of a material by pulling the fluid from an infinite reservoir.

Required equipment: Horizontal transmission support, menstrual fluid simulator prepared as described below, ruler, watch.

Process : Cut the materials to 1 inch (2.54 centimeters) of a width and to the desired length.

Fill the reservoir in the horizontal transmission device with a menstrual fluid simulator.

Place one end of the material in the simulator and place the rest of the material on the transmitting device.

Start timing Measure the distance transmitted in a given time, or the time to transmit a given distance.

Flat System Test Procedure The purpose of this procedure is to determine the fluid handling characteristics of the various absorbent systems through the analysis of the stain length, saturation capacity and fluid load of the system components. The required equipment includes hourglass-shaped acrylic plates (with a 0.25-inch hole in the center) weighing approximately 330 grams, syringes, an eighth-inch tube I.D. Tygon, a pipette pump, menstrual fluid simulator and a laboratory balance (exact to 0.00 g).

The samples to be tested are cut to a desired shape (concurrently 1.5 inches by 5.5 inches for the absorption / distribution layers of fluid or capillary fabrics, 1.75 inches by 5.5 inches for the transfer delay layers, and 200 mm of hourglass shape for long retention layers). The 5.5-inch layers are made in 1.1-inch sections and the pad layer is marked in sections that correspond to the marks on the 5.5-inch layers when they are centered over the pad layer. Each component is heavy and the weight is recorded. The individual components are assembled into a desired component system by keeping the marked sections aligned and one end is labeled as the top. The syringes are filled with a menstrual fluid simulator and a Tygon tube attached to the syringes. The syringes are placed in a pipette pump which is programmed to deliver a given amount of simulator, currently a 30 cubic centimeter syringe delivers a specified amount of simulator (usually 10 ml) in one hour. With the open ends of the tubes placed in a beaker, the tube is primed by running the pump until all the air is out of the tube and the simulator is coming out of the tube at the discharge end. The component systems that are to be tested are placed near the pip ta pump and a 2-inch by 6-inch piece of 25 grams per square meter, lOd BCW is placed on top of the center of the system over which an acrylic plate is placed, also centered on the upper part of the system. The free end of a tube is inserted into the hole of the acrylic plate and the pipette pump begins to start discharges. At the end of the discharge period, the tube and acrylic plates are removed. The BCW is then carefully removed without moving the underlying layers and discarded. Each layer is then individually weighed and the weight recorded. Then, starting at the end marked as the top, each section marked is cut and weighed. The length of the stain for each layer is measured and recorded and the data is put into a spreading sheet for the formation of graphs and analysis the fluid load (g / g) is calculated by dividing the amount of fluid absorbed in a material by the dry weight of the material. Fluid saturation is calculated by dividing the fluid load by the spot length.

Demand for Absorbency Transmission Capacity; The objective of this test is to determine the fluid handling characteristics of various absorbent systems through the analysis of the stain length, the saturation capacity, and the fluid loads of the components of the system.

Required equipment: Hourglass-shaped acrylic plates (with a 0.25 inch (6.35 mm) hole in the center) weighing approximately 330 grams; syringes; tube one octa * inch (3.175 millimeters) in internal diameter (ID) (for example Tygon®); pipette pump; menstrual fluid simulator prepared as described below; laboratory balance (exact at 0.00 g).

Process : 1. Cut components to the desired shape; 1.5 inches (3.8 centimeters) by 6.0 inches (15.2 centimeters) for the absorption / distribution layers, 3.0 inches (7.6 centimeters) by 6.0 inches for the perimeter and transfer delay layers of non-woven fabric bonded with yarn. 2. Mark the 6.0-inch layers in sections of 1.2 inches (3 centimeters). If the perimeter layer is oval, mark in sections that correspond to the marks on the absorption / distribution strip when centered on the perimeter layer. 3. Weigh each component and record the weight, 4. Assemble the individual components in the desired absorbent system keeping the marked sections aligned. Mark an extrusion as the top.

. Fill the syringes with a menstrual fluid simulator and attach the tubes to the syringes. 6. Place the syringes in the syringe pump. 7. Program the size of the syringe inside the syringe pump. 8. Schedule the pump (currently using 30 centimeter syringes, cubic at a rate of 10 ml per hour. 9. With the open ends of the tube placed in a pointed glass, prepare the tube by running the pump until all the air is out of the tube and the simulator is coming out of the tube at the open end.

. Place the component systems to be tested near the syringe pump, place a piece of 2 inches (5.1 centimeter ^) by 6 inches (approximately) of 25 grams per square meter, woven and knitted fabric material of 10 denier on the upper layer of the absorbent system to avoid transmission on the acrylic plate and place an acrylic plate centered on top of the system. 11. Insert the open end of a tube into the hole in the acrylic plate. Repeat regarding the remaining systems that are going to be tested.

Proof 1. Turn on the pipette pump to start the discharge. 2. Add 3 more of menstrual fluid simulator at a rate of 10 mis per hour. 3. After 3 misses have been discharged into the product, add weights to the acrylic plate to achieve a pressure of 0.08 pounds per square inch. 4. Continue downloads for another 5 mis, so they are downloaded a TOTAL of 8 mis.

. At the end of each discharge period, remove the tube and acrylic plates. Carefully remove the carded and bound fabric without moving the underlying layers and discard it. 6. Take pictures of the component system and the layers and print them.

Weigh each layer individually and record the weight, 8. Start at the end marked as top, cut and weigh the first sections marked and the weight. Repeat for the remaining sections and layers. 9. Measure and record the spot length for each layer. i 10. Insert the data into a spreadsheet for graph formation; and analysis.

Preparation of the Menstrual Fluids Simulator; In order to prepare the fluid, blood, in this case defibrinated pig blood, was separated by centrifugation at 3000 revolutions per minute for 30 minutes, although other methods or speeds and times may be used if they are effective. The plasma was separated and stored separately, the curd layer was removed and discarded and the packed red blood cells were stored separately as well.

The eggs, in this case large chicken eggs, were separated, the yolk and the chalazas were discarded and the egg white was saved. The egg white was separated into the coarse and thin portions by filtering the clear through a nylon mesh of 1,000 microns for about 3 minutes, and the thinnest part was discarded. Note that the alternate mesh sizes may be used and the time or method may be varied as long as the viscosity is at least required. The thick part of the egg white which was retained on the mesh was collected and pulled into a syringe of 60 cubic centimeters which was then placed on a programmable syringe pump and homogenized by ejecting and refilling the contents five times. In this example, the amount of homogenization was controlled by the syringe pump rate of about 100 ml / minute, and the inner diameter of the tube of about 0.12 inches. After homogenization, the coarse egg white had a viscosity of about 20 centipoise to 150 seconds "1 and was then placed in the centrifuge and rotated to remove detritus and air bubbles at around 3,000 revolutions per minute for about 10 minutes, although any effective method can also be used to remove debris and bubbles.

After centrifugation, the thick homogenized egg white, which contains ovamucin, was added to a Fenwal® transfer pack of 300 cubic centimeters using a syringe. Then 60 cubic centimeters of pig plasma were added to the transfer package. The transfer pack was fastened, all air bubbles were removed, and placed in a laboratory mixer Stomacher where it was mixed at a normal (or average) speed by 2 minutes. The transfer pack was then removed from the mixer, 60 cubic centimeters of red blood pig cells were added, and the contents were mixed by hand by kneading for 2 minutes or until the contents appeared to be homogeneous. A hematocrit of the final mixture showed a red blood cell content of about 30 percent by weight and should generally be at least between a range of 28-32 percent by weight for artificial fluids made in accordance to this example. The amount of egg white was around 40 percent by weight.

The ingredients and equipment used in the preparation of these artificial menstrual fluids are readily available. Below is a list of the sources for the items used in the example, although of course other sources can be used provided they are approximately equivalent.

Blood (pig): Cocalico Biologicals, Inc., 449 i Stevens Road, Reamstown, PA 17567, (717) 336-1990.

Fenwal® transfer pack container, 300 ml, with coupler, sample 4R2014; of Baxter Healthcare Corporation, Fenwal Division, Deerfield, IL 60015.

Harvard programmable syringe pump model number 55-4143: Harvard apparatus, South Natick. MA 01760.

Laboratory mixer Stomacher 400 model number BA 7021, series nunjero 31968: Seward Medical, London, England, United Kingdom. 1000 micron mesh, item number CMN-1000-B: Small Parts, Inc., PO Box 4650, Miami Lakes, FL 33014-0650, 1-800-220-4242.

Hemata Stat-II device for measuring hemograms, series number 1194Z03127: Separation Technology, Inc., 1096 Rainer Drive, Altamont Springs, FL 32714.

Rate Block Absorption Test This test is used to determine the absorption time of a known amount of fluid within a material and / or a material system. The test apparatus consists of a rate block 10 as shown in Figure 1.

A piece of absorbent 4 inches by 4 inches 14 and cover 13 are cut by matrix. The specific covers are described in the specific examples. The absorbent used for these studies was normal and consisted of 250 g / square meter placed by air 'made of 90% Coosa 0054 and 10% HC binder T-255. The total density for this system was 0.10 g / cc. The cover 13 was placed on the absorbent 14 and the rate block 10 was placed on top of the two materials. 2 mL of menstrual fluid simulator was delivered to funnel 11 of the test apparatus and timing was started. The fluid moved from funnel 11 to channel 12 where it was delivered to the material or material system. The stopwatch was stopped when all the fluid was absorbed and the material or material system is observed from the chamber in the test apparatus. The absorption time for a known known fluid amount was recorded for a given material or for a material system. This value is a measure of an absorbency of a material or material systems. Typically, five to ten repetitions were carried out, and the average absorption time was determined.

Reh test? This test was used to determine the amount of fluid that will return to the surface when a load is applied. The amount of fluid that flows back through the surface is the value of "re-wetting." The more fluid comes to the surface, the greater the value of "rewetting". The lower rewet values are associated with a drier material and, therefore, a drier product. In the consideration of rewetting, three properties are important: (1) absorption, if the material / system does not have a good absorption then the fluid can be rewetted, (2) capacity of the absorbent to retain the fluid (the more the absorbent retains the fluid , the lower the availability for rewetting) and (3) the return flow, the more the cover is forbidden for the fluid to return through the cover, the lower the rewet. In our case, we evaluated the cover systems where the absorbent was kept constant and, therefore, we only worry about the properties (1) and (3), absorption and return flow respectively.

A 4-inch by 4-inch piece of absorbent and cover was cut with matrix. The absorbent used for these studies was normal and consisted of an air-laid material of 250 g / square meter made of 90% Coosa 0054 and 10% binder -IC T-255. The total density for this system was 0.10 g / cubic centimeter. The cover was placed on the absorbent and the rate block was placed on top of two materials. In this test, 2 mL of menstrual fluid simulator are insulted in the rate block apparatus and allowed to be absorbed into a 4 inch by 4 inch sample of the cover material which was placed on top of an absorbent piece. 4 inches by 4 inches. The fluid was allowed to interact with the system for one minute and the block rate rests on top of the materials. The absorbent and the cover of the material system are placed on a bag filled with fluid. A piece of blotting paper is heavy and placed on top of the material system. The bag is traversed vertically until it is brought into contact with an acrylic plate above it, thus pressing the entire material system against the first side of the plate blotting paper. The system is pressed against the acrylic plate until a total pressure of 1 pound per square inch has been applied. The pressure is kept fixed for 3 minutes, after which the pressure is removed and the blotting paper is heavy. The blotter retains any fluid that has been transferred to it from the cover / absorbent system. The difference in weight between the original secant and the secant after the experiment is known as the "rewet" value. Typically, five to ten repetitions were carried out, and the average rewet was determined.

Stain / Absorption Test A spotting / absorption test was developed which allows to observe the spot size, the intensity and the fluid retention in the components with the pressure and fluid flow rate. The menstrual fluid simulator was used as the test fluid. A piece of absorbent 4 inches by 4 inches and the cover were cut. The absorbent used for these tests was normal and consisted of an air-laid material of 250 g / square meter made of 90% Coosa 0054 and 10% HC T-255 binder. The total density of this system was 0.10 g / cubic centimeter. A system of material, casing and core measuring 4 inches by 4 inches was placed under an acrylic plate with an ø-one-inch diameter hole punched in the center. A piece of one-eighth-inch tube was connected to the hole with an accessory. The menstrual fluid simulator was delivered to the sample using a syringe pump at a rate specified by a specified value. The pump was programmed to deliver a total volume of 1 mL to the samples, where the samples were under pressures of 0 pounds per square inch, 0.0078 pounds per square inch, and 0.078 pounds per square inch. These pressures were applied using a weight which was placed on top of the acrylic plates and distributed evenly. The flow rate of the pump was programmed to deliver the fluid at a rate of 1 mL / second. The spot size for the cover materials was measured manually, and the amount of fluid in each component of the system was measured by weighing before and after the absorption of the fluid. The intensity of the stain was evaluated qualitatively by comparing the samples. The spotting information was recorded using a digital camera and can also be analyzed with an image analysis.

Permeability The permeability is obtained from a measurement of the resistance of the material to the flow of the liquid. A liquid of a known viscosity is forced through the material of a given thickness at a constant flow rate and the resistance to flow, measured as a pressure drop is monitored. Darcy's law is used to determine permeability as follows: Permeability = [Flow rate x thickness x viscosity / pressure drop] Equation (1) i where the units are: permeability: cm2 or darcy 1 darcy = 9.87 x 10"9 cm2 flow rate: cm / second viscosity: pascal / second pressure drop: pascals The apparatus consists of an arrangement in which a piston with a cylinder pushes a liquid through the sample to be measured. The sample is gripped between two aluminum cylinders with the cylinders oriented vertically. Both cylinders have an outer diameter of 3.5 inches, an inner diameter of 2.5 inches and a length of about 6 inches. The tissue sample 3 inches in diameter is held in place by its outer edges and therefore is completely contained within the apparatus. The lower cylinder has a piston that is capable of moving vertically inside the cylinder at a constant speed and is connected to a pressure transducer which is capable of monitoring the pressure found by a column of liquid supported by the piston. The transducer is positioned to move with the piston so that there is no additional pressure measured until the column of liquid makes contact with the sample and is pushed through it. At this point, the additional pressure measured is due to the resistance of the material to the flow of the liquid through it.

The piston is moved by a sled assembly that is driven by a stepped motor. The test starts by moving the piston at a constant speed until the liquid is pushed through the sample. The piston is then stopped and the pressure of the baseline is noted. This corrects the effects of floating the sample. The movement is then summed up for a suitable time to measure the new pressure. The difference between the two pressures is the pressure due to the resistance of the material to the flow of the liquid and is the pressure drop used in equation (1). The piston speed is the flow rate. Any liquid whose viscosity is known can be used, even when a liquid that moistens the material is preferred since this ensures that the saturated flow is achieved. The measurements described here were carried out using a piston speed of 20 cm / minute, a mineral oil (Peneteck Technical Mineral Oil manufactured by Penreco of Los Angeles, California) of a viscosity of 6 centipoise.

Alternatively, the permeability can be calculated from the following equation: permeability = 0.051 * R * (I-Porosity) * (Porosity / (I-Porosity)) 2-75, • Equation (2) where R = fiber radius and Porosity = 1 - (fiber density / density of the fabric) Equation (3) The reference for equation (2) can be found in the article "Quantification of the Permeability of Unidirectional Fiber Bed "by J. Westhuizen and JP Du Plessis i in the Journal of Compound Materials 28 (7), 1994. Note that the equations show that the permeability can be determined if the fiber radius, the density of the fabric and The density of fiber are known.

The conduction is calculated as permeability per unit thickness and gives the measurement of the opening of a particular structure and, therefore, an indication of the relative ease at which the liquid will pass through the material. The units are darcies / thousandth of an inch.

DETAILED DESCRIPTION OF THE INVENTION In its broadest embodiment, the invention is a pad for the hygiene of women that comprises a cover of rapid absorption adjacent to a capillary fabric having regions of variable capillarity which allows the passage of fluids in particular areas, and which it is on one side of a retaining layer of the absorbent core. The fabrics used in the practice of this invention can be made through a variety of processes including air laying, spinning, meltblowing, carding, coforming, and foaming processes. when air placement for the absorption / distribution layer and spinning for the transfer delay layer are preferred. The various layers can be made of synthetic polymers and natural fibers. Polyolefins such as polyethylene and polypropylene are particularly preferred due to cost.

It is important that the cover pull the discharges quickly into the product. A number of materials provide such absorption properties. These include bolt-punched films, vacuum perforated films, perforated non-wovens and co-perforated film / non-woven laminates, fabrics bonded with conjugated fiber yarn, fabrics linked with creped yarn, fabrics placed by air , carded and knitted fabrics, fabrics tied with yarn, etc. A number of types of fabrics may be acceptable which may be initially unsuitable through the use of topical chemical treatments and mechanical processing. Any material which, when combined with an absorbent core, allows rapid absorption, low staining, low rewet and low fluid retention, under all flow conditions may also be suitable.

The wicking fabric is an absorption / distribution layer which can be made of a variety of fibers and blends of fibers including synthetic fibers, including natural fibers, mechanically and chemically smoothed pulp, basic fibers, chips, fibers blown with fusion and linked with spinning, superabsorbents and the like. The fibers in such a fabric can be made of fibers of the same diameter or of a variable diameter and can be of different shapes such as 5 lobes, 3 lobes, elliptical, round, etc. The absorption / distribution layer can be made by a number of methods, including air placement, hydroentanglement, bonding and carding, and coforming, even when air placement is preferred.

The transfer delay layer can also be made from a variety of fibers in a variety of shapes and sizes. The transfer delay layer can be made according to a number of processes such as spun bonding, carding, meltblowing and film forming, even when spinning is preferred.

The retention layer materials may be made of materials or substances known in the art to absorb the liquid as well as any others that may be developed for this purpose.

Examples include fast and slow superabsorbents, pulps, and mixtures thereof. Mixtures of superabsorbents and pulp used as retention materials can be used in proportions of between about 100/0 and 0/100 by weight, more particularly between about 80/20 and 20/80.

Synthetic fibers include those made of polyamides, polyesters, rayon, polyolefins, acrylics, superabsorbents, Lyocel regenerated cellulose and any other suitable synthetic fibers known to those skilled in the art. The synthetic fibers can also include cosmotropes for the degradation of the product.

Many polyolefins are available for fiber production, for example, polyethylenes such as ASPUN® 6811A linear low density polyethylene from Dow Chemical, linear low density polyethylene 2553 and high density polyethylene 25355 and 12350 are such suitable polymers. The polyethylenes have melt flow rates, respectively, of about 26, 40, 25 and 12. The polypropylenes that form the fiber include Escorene® PD 3445 polypropylene from Exxon Chemical Company and PF-304 from Montell Chemical Company. Many other polyolefins are commercially available. i Natural fibers include wool, cotton, linen, hemp and wood pulp. The pulps include the standard soft wood fluff class such as Coosa Mills CR-1654 from Coosa, Alabama, the high volume formaldehyde additive free pulp (HBAFF) available from Weyerhaeuser Croporation of Tacoma, WA, and which is a Southern softwood pulp fiber cross-linked with an increased moisture modulus and a chemically crosslinked pulped fiber such as Weyerhaeuser NHB-416. The free pulp of high volume formaldehyde additive has a chemical treatment that settles in a curling and twisting, besides imparting a wet and dry stiffness and an elasticity to the fiber. Another suitable pulp is the Buckeye HP2 pulp and yet another one is IP Supersoft from International Paper Corporation. Suitable rayon fibers are Merge 18453 1.5 denier fibers from Courtaulds Fibers Incorporated of Axis, Alabama.

Several superabsorbents in a number of ways are available. Commercially available examples include the FAVOR® 870 superabsorbent spheres from the Stockhausen Company of Greensboro, North Carolina 27406, which is a highly cross-linked surface superabsorbent, XL AFA 94-21-5 'and XL AFA-126- 15, which are suspensions of 850 to 1400 microns of polymerized polyacrylate particles from Dow Chemical Company of Midland, Michigan and SANWET® IM 1500 superabsorbent granules supplied by KoSA, Inc. (formerly, Trevira, Inc., and formerly-Hoechst Celanese) PO Box 4, Salisbury, North Carolina 28145-0004.

The binders can also be included in the air bonded or air laid layers in order to provide mechanical integrity to the fabric. Binders i include fiber, liquid and other binding media which can be thermally activated. Preferred fibers for inclusion are those having a relatively low melting point such as polyolefin fibers. The lower melt polymers provide the ability to bond the fabric together at fiber crossing points with the application of heat. In addition, fibers having at least one component of a lower melt polymer, such as conjugated and biconstituent fibers, are suitable for the practice of this invention. Fibers having a lower melt polymer are generally referred to as "meltable fibers". By "lower melting polymers" is meant those which have a glass transition temperature of less than 175 ° C. Exemplary binder fibers include conjugated fibers of polyolefins and / or polyamides and liquid adhesives. Two such suitable binders with the conjugate sheath and core fibers available from KoSA, Inc., under the designation T-255 and T-256, even though many suitable binder fibers are known to those skilled in the art and are made by many. manufacturers such as Chisso and Fibervisions LLC of Wilmingjton, Delaware. A suitable liquid binder is the Kymene® 557LX binder, available from Fibervisions LLC.

Once produced, the tissue must be properly stabilized and consolidated in order to retain its shape. The inclusion of a sufficient quantity of meltable fibers and subsequent thermal bonding is the preferred method for obtaining adequate stabilization. It is believed that this method allows for proper bonding at the center of a coarse material as well as on the surface.

An example of a product form for a product for the hygiene of women for night use is shown in Figure 10; it has an absorbent system composed of a fabric cover bonded with creped yarn 10, a distribution / absorption layer placed by coperforated air 11 and a transfer delay layer of fabric bound with yarn 12, a lint retaining layer 13 and a formed perimeter layer formed 14.

A specific example will be a spun bonded cover of 13.6 grams per square meter (0.4 ounces per square yard) creped at 30 percent to a base weight of 20.3 grams per square meter (0.6 ounces per square yard) and treated with 0. 3 percent by weight of surfactant AHCOVEL® Base N-62 and a capillarity fabric made of a fabric placed by coperforated air of 175 grams per square meter, 90 percent by weight of Weyerhauser NF-405 and 10 percent by weight from KoSA T-255 at 0.12 g / cc and a transfer lag layer linked with yarn of 27 grams per square meter (0.8 ounces per square yard) made of polypropylene. A retention layer made of 500 grams per square meter, 0.06 g / cc to 0.09 g / cc, Weyerhauser NF-405 is included. A second retention layer made of 600 grams per square meter of 0.06 g / cc to 0.09 g / cc of Weyerhauser NF-405 is also included.

Under continuous flow conons, the fluid is rapidly absorbed into the absorption / distribution layer placed by air through the bonded cover with highly permeable and wettable creped yarn. The yarn-bound fabric transfer delay layer, which is co-perforated to the absorption / distribution layer placed by air, prevents the transfer of premature fluid to the underlying retention layer and forces the fluid to be distributed longitudinally in the product.

It is believed by the inventors that initial discharges are absorbed and remain in the absorption / distribution layer placed by air until saturation levels of 30 percent to 40 percent are achieved. (approximately 3-4 grams of fluid). At this saturation point in the absorption / distribution layer placed by air, the fluid begins to be transferred from the absorption / distribution layer, a. through the transfer delay layer to the underlying erasure hold layer. The lint retainer layer centered below the transfer delay layer absorbs the fluid that passes through the transfer delay layer when the product is insulted. The transfer delay layer controls the amount of fluid that is passed to the absorber below and facilitates absorption / distribution. As the amount of fluid in the absorption / distribution layer placed by air increases, the amount of fluid transferred through the transfer delay layer to the underlying flux increases. By transferring the fluid based on the level of fluid saturation, the transfer delay prevents high fluid saturation levels (> 80%) from occurring in the absorption / distribution layer placed by air. This function allows the absorption / distribution layer placed by air to keep the volume hollow for adonal discharges. The absorption / distribution layer placed by air returns to an equilibrium level of 30-40% fluid saturation during use between insults. i Even though the shape of the various layers is not considered critical to the success of the invention, it should be noted that the air retaining / absorption / distribution retaining layers can also incorporate a rectangular strip geometry of reduced dimension which prevents fluid from being transferred to the pad edges. The combination of transfer delay and absorption / distribution technology, aided in some degree by the specific material geometry, forces the fluid to remain at the center of the product in the X, Y and Z directions. The asymmetric perimeter layer (for example, in the form of an hourglass) it is also available to retain low fluid in medium at high product fluid loads (greater than 5 g), but primarily serves as a component of product formation. It should be noted that the shape of the retaining layer may be the same as or different from that of the perimeter layer and that any may have a rectangular, hourglass, racetrack or other shape. In adon, the engraving can be added to the retaining and / or perimeter layer to improve the integrity of the layer.

The theoretical fluid loading profile for this feminine hygiene product is illustrated in Figure 11. Figure 11 is a graph of the liquid content of the component (or charge) in grams on the Y axis and the total product charge. in grams on the X axis. The absorption / distribution of the material placed by air is shown by diamond on the graph, the retention layer by squares, and the perimeter layer as triangles. At low loads (0-3 ml), the fluid is mainly absorbed in the absorption / distribution layer placed by air. By increasing the fluid load (3-5 ml), fluid begins to transfer through the transfer delay layer into the retaining layer and slightly into the perimeter layer. At this time, very little fluid from the adonal discharges is maintained in the absorption / distribution layer placed by air. The absorption / distribution layer placed by air continuously regenerates its hollow volume by transferring the fluid to the retaining layer so that subsequent discharges can be accommodated. At higher loads (>5 ml), the retaining layer retains most of the fluid due to its high void volume. The. Perimeter layer has the ability to retain any residual fluid which is passed through the retaining layer due to localized saturation. The perimeter layer also provides additional coverage for downloads outside the target area. Under gushing situations (> lml / second and 5ml / discharge), the women's hygiene product functions similarly to the theoretical filling profile described above but also demonstrates several additional functional characteristics. When an outbreak occurs, it is absorbed in the hollow volume of the highly permeable creped cover and within the absorption / distribution layer placed by air. Under bubbling conditions, the openings in the absorption / distribution layer placed by air provide an internal hollow volume and increased permeability which helps to absorb and store the fluid. The openings help to store the fluid by providing an immediate internal reservoir for the fluid until it is absorbed into the structure by surrounding air. This function is critical since a gush discharge occurs so fast that momentary localized saturation occurs in the non-perforated part of the fabric placed by air. During spurt discharges, the openings also provide a direct path to the underlying liner retention layer so that the fluid can be immediately transferred to the lint layer and the hollow volume can be rapidly regenerated in the layer placed by air. . By regenerating the hollow volume, the layer placed by air is available for future discharges.

Immediately after the outbreak is absorbed, the absorption / distribution and transfer characteristics of the transfer / distribution delay system coperforated absorption takes over. The fluid is distributed in the absorption / distribution layer placed by air and is transferred through the transfer delay layer until the saturation equilibrium level of 30 percent to 40 percent fluid is achieved in the layer of distribution / absorption placed by air. This equilibrium process again helps the regeneration of the hollow volume in the absorption / distribution layer so that it is available to take additional discharges. A suitable absorption / distribution layer horizontally transmits menstrual fluids at a distance of from about 1.2 centimeters to about 15.25 centimeters.

Material Properties of 'Cover: It is important that the cover pull the discharges quickly into the product. A number of materials provide such absorption properties. These include bolt-punched films, vacuum perforated films, perforated non-wovens and co-perforated film / non-woven laminates, fabrics bonded with conjugated fiber yarn, fabrics bonded with creped yarn, fabrics placed by air, carded and knitted fabrics, fabrics linked with yarn, etc. A number of fabric types which may be initially unsuitable can be made acceptable through the use of topical chemical treatments and mechanical processing. Any material which, when combined with an absorbent core, allows for rapid absorption, low staining, low rewet and low fluid retention under all flow conditions may be suitable.

The non-woven fabric bonded with spinning and creping is preferred as the cover material for the personal care product as it creates benefits that can be raised in the design of an absorbent bubble-handling core. These benefits are a result of the fundamental property changes that occur during the creping process. In order to characterize the structural differences that exist between the cloth bound with standard yarn and the cloth bound with creped yarn and to identify the impact of the creping of the yarn bound fabric with the handling of the vials, two samples have been compared. One sample was a material bonded with polypropylene yarn of 3.5 denier per fiber, 20.3 grams per square meter (0.6 ounces per square yard), and the other was a material bonded with polypropylene yarn of 3.5 denier per fiber, 13.6 grams per square meter (0.4 ounces per square yard) creped 30% to an effective basis weight of 20.3 grams per square meter. Both materials were treated with 0.30% by weight of AHCOVEL surfactant. The structural differences can be better characterized by comparing the pore size distributions of the base material with the creped material. Figure 8 is a graph of the pore size distribution for these two samples. In Figure 8, the Y axis is the pore volume in cubic centimeters / g and the X axis is a pore radius in microns. The fabric linked with spinning and creping is denoted by the line that makes the first peak to the left.

The peak pore size for the tea bonded with standard yarn is 80 microns while the peak pore size of the cloth linked with creped yarn is 170 microns. The peak pore size increases with creping because it is believed that the primary bonds are deformed and the pores in the Z direction are formed, thereby creating a three-dimensional pore structure. The overall increase in caliber results in an increase in the total pore volume and a change corresponding to a larger pore size. By comparison, the pore structure of the fabric bonded with standard yarn is two dimensional due to its relatively flat surface structure. The larger pore size and the increased permeability of the fabric bonded with spinning and creping allows the fluid to enter the product more easily. In addition, larger pores are better suited to handle the variety of menstrual fluid types that are associated with heavy flow and / or spurting.

The breathing of the pore size distribution also increases with creping. The area under each of the curves in Figure 8 represents a measure of the pore volume for the material. As illustrated by the curves, the pore volume is much higher for the fabric bonded with yarn and crepe compared to the fabric bound with standard yarn. The increase in total pore volume facilitates the absorption of fluid and allows the product to accommodate a variety of flow types without failure. Figure 9 shows the three-dimensional structure of the cloth cover bonded with yarn and creped in a SEM-image at an amplification of one inch equal to 2 millimeters.

The additional structural differences between the spunbond, standard and creped fabrics are delineated in Table 1. As can be seen from Table 1, the thickness of the cloth bonded with spinning and creping is about 2.5 times that of a bonded fabric. not creped. The thickness creates a barrier between the product and the woman's body and promotes dryness of the skin by reducing the wetting typically caused by rewetting. Secondly, the permeability of the fabric bonded with spinning and creping is significantly greater than that of the yarn bound and standard cloth. This increase in permeability is believed to be due to two factors. The decrease in the density of the fabric bonded with spinning produced by creping and the partial orientation of the fibers out of the plane of the fabric. Both of these factors decrease the amount of fiber surface that is in contact with the test media and thus provide a lower resistance to flow, which facilitates rapid absorption.

Table 1: Comparison of Structural Properties for Spunbonded Fabric and Linked Fabric with Spun Yarn The differences in the structural properties of the fabrics have a profound effect on the functional properties exhibited by these fabrics, as described above. Table 2 shows how various functional properties are dramatically improved for the bonded and creped bonded cover fabric compared to a fabric bonded with standard non-creped yarn. The results are indicative of the contributions of the creped cover alone when tested on an absorbent core placed by standard air.

Table 2: Comparison of Functional Properties for Spunbonded and Spunbond Woven and Creped The absorption time is cut in half due to the increase in permeability and the hollow volume that is introduced by the creping *. The cloth cover linked with spinning and creping results in. the rewet which is 16% of the rewet that occurs with the fabric cover bonded with standard yarn. This reduction occurs due to the increase in permeability, pore size and thickness of the cloth cover bonded with spinning and creping. The increase in permeability promotes the transport of fluid to the absorbent number and the large average pore size ensures that the fluid is not held tightly within the interfiber space of the cover, thereby being easily desorbed by the absorbent core. This reduces the fluid retention in the cover which reduces rewetting and staining by reducing the amount of fluid that is in contact with or in close proximity to the top surface of the cover. The increased fluffiness of the structure provides separation of the absorbent core and thus provides a barrier to the return flow of the fluid. There is also some reduction in the intensity of the stain due to the masking that occurs as a result of the thickness of the material.

The functional improvements of faster absorption and reduced rewetting, retention and spot size make the cover bonded with creped yarn an ideal candidate for incorporation into an absorbent bubble management system. The cover bonded with spinning and creping should be lightweight, preferably within about 10 and 30 grams per square meter, more particularly within about 15 and 25 grams per square meter, with between about 20 and 50 percent of creped, more particularly between about 25 and 40 percent.

Absorption Layer / Coperforated Distribution / Transfer Delay The absorption / distribution layer and the transfer delay layer with co-perforations using the mechanical bolt perforation, even though the holes can also be provided by the die cutting or the formation of materials in such a way that they are produced with holes in them. the place. The objective is the production of a material which has regions of high and low capillarity to produce a "capillary cloth" which preferably allows fluid movement in some areas but restricts or prohibits it in others. The fluid transfer delay layer for the personal care absorbent products according to this invention is designed to increase the distribution in the XY plane by delaying the transfer of fluid from the absorption / distribution layer to the retaining layer . The preferred form of the capillary fabric is produced by the co-perforation of a fabric placed by air and a fabric bonded with yarn, even though a perforated non-woven fabric or a recorded non-woven fabric may also work. The coperforation of the transfer delay and absorption / distribution layers provides unique characteristics for the management of bubble discharges. A unique material is created with a trimodal pore structure consisting of 1) pores in the volume placed by air which are characteristic of the original structure in the case of materials placed by air, 2) large hollow spaces defined by the bolts of the drilling process and 3) small interfacial pores that surround the perimeter of the perforations. The openings are typically characterized by an open structure which tapers within a rounded cone-like structure as seen from the side placed by compound air. The interfacial pores are smaller than the surrounding pores due to the densification and relocation of the fiber that results from the drilling process.

The transfer delay layer provides a permeability and wetting gradient between the absorption / distribution layer and the underlying retaining layer by avoiding intimate contact between the two layers. The transfer delay layer must have a relatively low permeability and wetness so that it promotes the distribution of lateral fluid in the absorption / distribution layer under continuous flow conditions and to control the movement of the fluid in the Z direction. The transfer delay layer can be modified by topical chemical treatments known to those skilled in the art because they affect the hydrophobicity of a material. Some chemicals suitable for modifying wettability are marketed under the trade names AHCOVEL®, Glucopon®, Pluronics®, Triton® and Masil SF-19®. The transfer delay promotes the lateral distribution (XY) and the absorption / distribution layer resulting in the accumulation of fluid in the absorption / distribution layer, and then allows the transfer of fluid to the retention layer when high saturation levels occur or of high pressures.

It is believed by the inventors that the fluid does not move i preferably within the openings under conditions of continuous flow. This controlled transfer mechanism results in an elongated spot pattern in the retention layer and prevents oversaturation in the discharge area and provides a visual signal to the user indicating the remaining life of the product.

Under gushing conditions, the openings in the transfer delay layer allow the fluid to pass immediately through the underlying retention layer.

Figure 2 illustrates the trimodal pore structure of the co-perforated material. .In Figure 2 three kinds of pores are illustrated. The large pores 1 are located at the point where the fabric was perforated. The smallest pores 2 exist in the fabric placed by original air 4. Yet another class of pores 3 can be found in the area surrounding the point where the fabric was perforated due to the densification of the tea and the relocation of the fiber during the drilling process.

Figures 3, 4 and 5 show SEM images of the openings. Figure 3 exhibits an opening on the air-placed side of the composite at an amplification of one inch (2.54 centimeters) 'equal to one millimeter. Figure 4 shows an approach of an opening on the air-placed side of the compound at an amplification of one inch equal to 200 microns and Figure 5 exhibits an opening on the side linked with spinning of the compound at an amplification of one inch equal to 2. millimeters Figure 6 compares the pore size distribution of a material placed by air and perforated with a material placed by non-perforated air. In Figure 6, the material placed by non-perforated air is identified by the large dark squares and the material placed by perforated air (at a bolt density of about 2.5 bolts / cm2) by the lighter colored diamonds. The pore volume (cc / g) is on the Y axis and the pore radius (micras) on the X axis. This graph indicates that there is a slight change towards the smaller pores with the perforated material. This is due to a slight densification of the material around the openings. The large pores which are created by the openings are not represented in the graph due to their larger size. These provide, however, an additional hollow volume for the material. Figure 7 illustrates the detail of a single opening in relation to the functional of the absorbent compound. In Figure 7 a discharge (notice by the arrows) is delivered to the cover 1. The discharge flows through the cover 1 to the coperforated laminate of the invention where it passes through the absorption / distribution layer 2 either in opening 3 or through layer 2 itself. The discharge can also be distributed laterally along its length to other areas within the absorption / distribution layer 2. Much of the discharge eventually passes through the absorption / distribution layer 2 and the transfer delay layer 6 to the absorbent retention core 4.

The functional of the coperforated system can be broken into five areas: roof desorption; Increased surface area, opening hollow volume, access to the eraser, and transmission capacity. Each of these functionality benefits are discussed individually below. i 1. Decubitus Deck The non-perforated areas of the absorption / distribution layer material maintain a high degree of capillarity after discharge and are very suitable for desorbing the lining. Small pores of preferred air-laid material provide the capillarity necessary to desorb large pores from the cover, thereby removing a majority of the fluid from the surface of the product. The improved desorption of the roof results in low levels of mud and cover staining. 2. Increased Surface Area the perforated areas of the absorption / distribution layer material provide an increased surface area for fluid absorption. During gusts, the fluid that contacts the opening can be absorbed in the X, Y, and Z directions through the wall of the opening, rather than strictly in the Z direction through the upper surface. Therefore, the increased surface area provided by the walls of the perforations increases the absorption characteristics of the absorbent layer placed by air. Additionally, the perforations increase the overall permeability of the absorption / distribution layer. 3. Hollow Opening Volume The open areas and the hollow volume created by the openings allow the fluid to be internally accumulated in the product prior to absorption within the absorption / distribution layer material itself. This prevents stagnation on the surface of the pad and facilitates absorption when the localized saturation of the absorption / distribution layer prohibits immediate fluid absorption. 4. Access to the Retention Layer The openings in the absorption / distribution layer material provide a direct fluid path to the fluff in the perforated areas. Under flowing conditions, the fluid passes directly through the opening and into the retaining layer. By providing immediate access to the holding capacity under these conditions, the hollow volume of the absorption / distribution layer is maintained and the absorption times for multiple discharges are reduced.

. Transmission Capacity When the absorption / distribution layer material is the preferred air laid fabric, its stability and high degree of wet integrity do not allow the pores to bend to an appreciable degree when the product is discharged. The stable pore structure allows capillary transmission to laterally transport fluid out of the discharge area and to other regions of the product. The non-perforated areas of the material placed by air maintain this function and capillary transmission prevents high saturation from occurring in the discharge area. The capillary transmission in combination with the stability of the materials allows the hollow volume to be regenerated after a discharge so that additional discharges can be accepted.

The experiments were carried out to examine the preferred forms of the invention. Three different base weights of the fabrics placed by air were evaluated: 100, 175 and 250 grams per square meter. Comparisons were made between the three fabric samples placed by air and a perforated control sample. The drilling pattern in Figure 12 was initially used and had 48 bolts / square inch (7.4 bolts / cm2) using bolts with a diameter of 0.081 inches (2.06 millimeters).

These materials were tested on the absorbent waste core using the flat system distribution test. Key measurements included the size of the stain, the determination of whether the saturation profile was even or skewed, and the amount of fluid retention and transfer in the layer placed by air. These results are summarized in Table 3.

Table 3; Flat System Fluid Distribution Test / Coperforated Material Matrix * The densities reflected / above are pre-perforated densities, the densities of the perforated materials are superior.

This test showed a decrease in the length of the stain as well as a retention of fluid in the perforated samples compared to the control, indicating that the perforation of the fabric placed by air increases the density of the fabric placed by air dramatically because the density of bolts from the initial drilling pattern (Figure 12) was so high. This is most noticeable on the samples of an original high density and a high basis weight. As the density increases, the pore size and the void volume of the fibrous regions of the materials placed by air decrease.

As a result of this sample test, it was determined that the drilling had the potential to impact the performance of the product. An additional test was carried out at a bolt density of 16 bolts / square inch (2.5 bolts / cm2) (shown in Figure 13) for the minimum increases in material density after drilling. The bolt diameter remained at 0.081 inches. The range of fabric density studied was narrowed to 175 to 200 grams per square meter and the fabric placed by air was co-perforated to a transfer delay layer of yarn bonded fabric to maintain the absorption / distribution functionality.

Tables 5 and 4 show the matrices of additional material that were evaluated. The transfer delay layers were polypropylene fabrics bonded with yarn except where the film is indicated. The transfer delay layers linked with spinning have a density and a basis weight as indicated. Spunbonded fabrics were not treated with surfactants so that they remained naturally non-wettable. The film was a polyethylene film of 1 thousandth of an inch thick.

Table 4: Coperforated Air Placement Material / Transfer Delay Layer Table 5; Co-punched Air Placement Material / Transfer Delay Layer The materials described in Tables 4 and 5 represent the materials which are believed to have a better potential for performance characteristics due to lower perforation pin density and lower base and / or start weight densities. These materials were tested for capacity, horizontal transmission capacity, saturation capacity, fluid division characteristics, and triple bubble capacity. Each of these areas is discussed individually below. As a result of this test, it is believed that the bolt density d be between about 10 and 40 bolts / square inch (1.6 and 6.2 bolts cm2) for proper operation.

Capacity Figure 14 shows the measured capacity for fabrics placed by air with and without perforations. In Figure 14, the upper line represents non-perforated air-laid fabrics of 175 grams per square meter and 200 grams per square meter, the middle line represents a fabric placed by co-perforated air of 200 grams per square meter and the lower line represents a coperforated fabric of 175 grams per square meter. The capacity decreases with increasing density as expected. The capacity is also slightly reduced for perforated samples. These data reveal a cloth placed by perforated air at 200 grams per square meter and 0.14 grams / cubic centimeter that have a capacity equivalent to a non-perforated cloth of 175 grams per square meter, 0.14 grams / cubic centimeter. í Transmission of Capillarity -Horizontal - Infinity Deposit The horizontal capillary transmission test was completed to evaluate the effect of the drilling process on the horizontal transmission distance. The horizontal transmission distance is important to maintain a visual signal which alerts the user that the product is approaching its capacity and must be replaced. Without an appropriate transmission functionality, the visual signal does not appear in the desired degree.

The results of the horizontal capillary transmission of the samples placed by low density air of 175 grams per square meter of Table 4 indicate that perforation of the material placed by air reduces the distance of capillary transmission. It is believed that the drilling process creates openings which interrupt the fluid path for transmission and create density gradients around each opening. The perforated materials transmitted between 17 and 30 millimeters less than the non-perforated samples, depending on an original density. A larger difference exists for materials which have a higher start density. These results are shown in Table 15 where the transmission distance in millimeters is shown on the Y axis and the time in minutes on the X axis. In Figure 15, the non-perforated fabric of 33.9 grams per square meter is the line higher, immediately below is the line for the non-perforated fabric of 27 grams per square meter, followed by the perforated fabric of 27 grams per square meter and the perforated fabric of 33. 9 grams per square meter. i Figure 15"also indicates that the interruption of the transmission path associated with the perforation has more impact on the horizontal transmission operation than the effect of increasing the increased density by air." This indicates that the preparation effect is not an effect of simple densification The horizontal transmission results indicate that there was a capillary discontinuity in the perforated samples which results in an interruption of the significant transmission trajectory.

In an effort to improve the transmission distance, the sample of fabric placed by air of higher density was punched and its capillary transmission operation was evaluated. Again, the results indicate that perforated samples of higher density do not transmit as much as the non-perforated control material. This further showed that the capillary break is a result of the drilling process and indicates that the capillary transmission distance can not be controlled by the density in the perforated materials.

Transmission Saturation Capacity To assess the level of saturation that results after the capillary transmission process, the saturated materials were selected and weighed. The level of gram saturation per gram was then calculated to determine how the drilling process affects the level of gram capacity per global gram of materials. Note that these saturation levels are based on capillary transmission and not on a soak and drip protocol.

Figure 16 shows the effect of the perforation on a saturation level for the samples placed by low density air of 175 grams per square meter of Table 4. The results indicate that not only decreases the horizontal transmission distance as a result of the drilling process, it also decreases the transmission saturation capacity. Perforated samples are much less saturated than non-perforated samples regardless of start density even when no significant differences were noted between samples that had different starting densities. The effect of the perforation seemed to be more dominant than the effect of the initial density. In Figure 16, the saturation in g / g is indicated on the y axis and the transmission distance in inches on the x axis. The uppermost line represents the sample of 0.1 g / cc non-perforated, the lower line represents the non-perforated sample of 0.08 g / cc, the next line below represents the coperforated sample of 0.08 g / cc and the lower line the co-perforated sample of 0.1 g / cc. All samples are 175 grams per square meter. The effect of perforation on the saturation of capillary transmission of materials placed by air of higher density was also evaluated. The perforated samples had gram saturation levels per gram lower than that of a non-perforated control.

It appears that the basis weight had a minimal effect on the horizontal transmission distance or the saturation level of the coperforated samples. Samples of 175 and 200 grams per square meter work similarly only if they noted slight differences between densities. The overall transmission distance was the same for the samples of 0.12 g / cc and i of 0.14 g / cc, but the saturation level of the samples of 0.12 g / cc was higher, believing that this is attributable to the higher hollow volume of the samples 0.12 g / cc.

Hair Transmission - Absorbance Defendant The objective of drilling and / or coperforation is to increase the flow management of gushing streams while maintaining proper absorption / distribution and fluid transmission characteristics. The infinite deposit horizontal transmission tests discussed above have shown that 'capillary transmission capacity and saturation capacity. are affected by the drilling process. Since the products undergo a variety of pressures and flow conditions, the transmission potential under the demanded absorbency was also studied. The test of horizontal transmission of demanded absorbency, the measurement measure of fluid distribution of flat system is used and the fluid is introduced to the product at a rate of 10 ml / hour.

The results showed that the materials are saturated evenly throughout their length, indicating that the transmission is not diminished by the perforation in a transmission location of demanded absorbency. It is believed that the stable structure of the fabric placed by air allows the fabric placed by air and perforated to be fully utilized even when it does not have the continuous capillary fluid paths that are found in a fabric placed by non-perforated air.

Characteristics of Fluid Division Under Conditions of Absorbance Defendant Figures 17 and 18 show the results of a test of the fluid separation characteristics of the material. In figures 17 and 18, the cover layer is indicated by a light vertical bar, the absorption / distribution layer by a dark bar and the perimeter layer by a white bar. In these figures the y-axis is the saturation in g / g and the x-axis is the distance of the pad section from the front edge. The test was carried out by delivering 5 ml at a rate of 10 ml / hour and under a pressure of 0.25 pounds per square inch. The division of the fluid is important to evaluate how the coperforation of the layers placed by air delay and transfer changes the characteristics of fluid transfer of the product. Ideally, the fluid should be distributed through the entire length of the layer placed by air and transferred through the transfer delay layer simultaneously.

Figure 17 shows that the control system (layer placed by non-perforated air of 175 grams per square meter, 0.14 g / cc using a transfer lag layer linked with yarn of 27 grams per square meter) does not allow any transfer of fluid to the perimeter layer of the product. Figure 18 shows that the co-perforated sample, (air-laid layer, 175 grams per square meter, 0.14 g / cc co-perforated using a transfer delay layer bonded with yarn of 0.8 ounces per square yard) allows transfer to the layer of perimeter erasure.

Triple Absorption Times The triple absorption test was completed on a number of materials placed by air to evaluate the effects of the coperforation on the absorption cups of the materials with different starting densities and different layers with transfer delay, the test was completed using discharges of 3.2 ml, separated by 9 minutes. In all bar graphs of the triple absorption test, the first discharge is indicated by a light bar, the second is indicated by a dark bar and the third is indicated by a white bar. The fabric placed by air, used in the samples for figures 19 and 20, was 90% by weight of pulp NB416 and 10% by weight of binder fiber Hoescht-Celanese T-245. In figures 19, 20 and 21, the y-axis is the absorption time in seconds.

In figure 19, the samples, moving from the left to the right are cloth placed by perforated air of 175 grams per square meter, 0.10 g / cc on eraser, cloth placed by non-perforated air of 175 grams per square meter, 0.10 g / cc with a layer of transfer lag linked with yarn of 27 grams per square meter on lint, a cloth placed by coperforated air of 175 grams per square meter, 0.08 g / cc with a layer of transfer lag linked with yarn of 27 grams per square meter on eraser, a fabric placed by coperforated air of 175 grams per square meter 0.08 g / cc with a layer of transfer delay linked with yarn of 33, 9 grams per square meter, a fabric placed by coperforated air of 175 grams per square meter 0.10 g / cc with a layer of transfer delay linked with yarn of 27 grams per square meter on eraser, a fabric placed by coperforated air of 175 grams per square meter 0.10 g / cc with an ac Transfer delay lane linked with yarn of 33.9 grams per square meter on the waste, In figure 20, the samples, moving from left to right are a cloth placed by perforated air of 200 grams per square meter, 0.14 g / cc on erase, a cloth placed by non-perforated air of 200 grams per square meter, 0.14 g / cc with a layer of transfer delay linked with yarn of 27 grams per square meter on eraser, a fabric placed by coperforated air of 200 grams per meter 0.14 g / cc square with a transfer delay layer linked with yarn of 33.9 grams per square meter, a fabric placed by coperforated air of 200 grams per square meter 0.14 g / cc with a layer of transfer delay linked with yarn of 27 grams per square meter on waste, a fabric placed by air, coperforada of 200 grams per square meter 0.14 g / cc with a layer of delay of a film of a thousandth of an inch on a fabric erased coloc by coperforated air of 200 grams per square meter 0.12 g / cc with one coat of film transfer delay of one thousandth of an inch over eraser, one fabric placed by coperforated air of 200 grams per square meter 0.12 g / cc with one layer of transfer delay linked with yarn of 27 grams per square meter on lint and a cloth placed by coperforated air of 200 grams per square meter of 0.14 g / cc with a transfer laminating layer linked with yarn of 33.9 grams per square meter erase Figures 19 and 20 below show that the triple absorption times are similar for all coperforated materials tested regardless of which layer of transfer delay was used and of what density the fabric was placed by air. The triple absorption times are superior to those of a standard air / waste system and are lower than the same system with a transfer delay layer but without perforation. These results indicate that immediate access to the underlying fluff layer has been greatly improved by co-perforation.

The triple absorption test on a complete bubble management absorbent system with a creped cover and coperforated absorbent system indicates the individual effects of each component.

Figure 21 shows the results of triple spurt absorption. In Figure 21, the samples, moving from left to right are a cloth cover bonded with yarn creped with a fabric placed by coperforated air of 175 grams per square meter 0.12 g / cc with a transfer delay layer bonded with yarn from 27 grams per square meter on lint, a cloth cover bonded with non-creped yarn with fabric laid by coperforated air of 175 grams per square meter, 0.12 g / cc with a layer of transfer lag linked with yarn of 27 grams per square meter over eras, a cloth cover linked with yarn and creped with a cloth placed by non-perforated air of 175 grams per square meter 0. 12 g / cc with a transfer lag layer bonded to yarn of 27 grams per square meter on lint, and a cloth cover bonded with non-creped yarn with a cloth placed by non-perforated air of 175 grams per square meter 0. 12 g / cc with a layer of transfer delay linked with yarn of 27 grams per square meter on the waste. i The results indicate that combining the bound cover with spinning and creping with a coperforated transfer / distribution / absorption delay layer decreases absorption times and facilitates faster absorption than all other samples.

It can be seen from these data that the samples with the cover bonded with yarn work better than with the samples with the cover linked with regular yarn. The coperforation made a smaller contribution than the choice of cover, but additional improvements were seen when the creped deck and the coperforated system were combined. The faster absorption times are believed to be a result of the increased fluid transfer to the fluff layer and the void volume that is generated in the absorption / distribution layer as a result of this.

The results reveals that the absorption / distribution layer should be a fabric placed by air of between about 150 per square meter and 300 grams per square meter, more particularly between about 175 grams per square meter and 225 grams per square meter. square meter, with a density between 0.05 g / cc and 0.18 g / cc, more particularly between about 0.08 g / cc and 0.14 g / cc. The transfer delay must be a film, a fabric linked with yarn or a melt blown fabric, more particularly a yarn bound fabric with a basis weight of between about 15 grams per square meter and 50 grams per square meter, even more particularly between about 25 grams per square meter and 35 grams per square meter.

Even when only a few example embodiments of this invention; have been written in detail above, those skilled in the art will readily appreciate that many modifications are possible in the example embodiments without departing materially from the teachings and novel advantages of this invention. Therefore, all such modifications are intended to be included within the scope of this invention as defined in the following claims. In the claims, the claims of means plus function is intended to cover the structures described here as carrying out the recited function and not only the structural equivalents but also the equivalent structures. Thus, even though a screw and a nail may not be structural equivalents in the sense that a nail employs a cylindrical surface to secure together the wooden parts, while a screw employs a helical surface, in the environment of the fastener of wooden parts, a screw and a nail can be equivalent structures.

It should also be noted that any patents, applications or publications mentioned herein are incorporated by this reference in their entirety.

Claims (21)

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

1. A pad for the hygiene of the woman that comprises a cover of fast absorption adjacent to a fabric of capillarity that has regions of variable capillarity which allows the passage of the fluids in particular areas, which is adjacent to a layer of retention of the nucleus absorbent.

2. The pad as claimed in claim 1, characterized in that said cover is made of a process selected from the group consisting of spinning, melt blowing, spinning, creping, film punching, foaming, air laying , conformation, joining and carding and combinations thereof.

3. The pad as claimed in claim 2, characterized in that said cover is made by a process of linking with spinning and has a basis weight of between about 10 and 30 grams per square meter and is creped by an amount between 20 and 50 percent.

4. The pad as claimed in claim 1, characterized in that said wicking fabric is a perforated nonwoven fabric.

5. The pad as claimed in claim 1, characterized in that said capillarity fabric is a recorded nonwoven fabric.

6. The pad as claimed in claim 1, characterized in that said wicking fabric comprises an absorption / distribution layer and a transfer delay layer.

7. The layer 'as claimed in claim 1, characterized in that the absorption / distribution layer horizontally transmits the menstrual fluids at a distance of from about 1.2 centimeters around 15.25 centimeters.

8. The pad as claimed in claim 6, characterized in that said transfer delay layer is adjacent to the absorbent core.

9. The pad as claimed in claim 8, characterized in that said transfer delay layer is a material selected from the group consisting of yarn bonded fabric, melt blown fabric, carded fabric and films.

10. The pad as claimed in claim 6, characterized in that said transfer delay layer is a yarn bonded fabric with a basis weight of between about 15 and 50 grams per square meter.

11. The pad as claimed in claim 6, characterized in that the absorption / distribution layer is a material selected from the group consisting of air-laid fabric, carded and bonded fabrics, conform materials, hydroentangled pulp fabrics. and blown fabrics with fusion.

12. The pad as claimed in claim 11, characterized in that the absorption / distribution layer is a fabric placed by air having a basis weight of between about 100 grams per square meter and 300 grams per square meter and a density of between about 0.05 g / cc and 0.18 g / cc.

13. The pad as claimed in claim 6, characterized in that the absorption / distribution and transfer delay layers are co-perforated with bolts at a density between about 1.6 and 6.2 bolts / square centimeter.

14. The pad as claimed in claim 6, characterized in that said absorption / distribution and transfer delay layers are co-perforated with bolts at a density of about 2.5 bolts / square centimeter.

15. The layer as claimed in claim 1, characterized in that the absorbent core comprises pulp and superabsorbent.

16. The pad as claimed in claim 4, characterized in that said superabsorbent is in a form selected from the group consisting of flakes, particles, spheres, foams and fibers.

17. A woman's hygiene pad comprising an outer cover of non-woven fabric bonded with spinning and creping adjacent to an air-laid fabric absorption / distribution layer of polyolefin fiber having a basis weight of between about 175 grams per square meter and 225 grams per square meter and a density of between »of 0.08 g / cc and 0.14 g / cc, co-perforated to a bolt density of between about 1.6 bolts / square centimeter and 6.2 bolts / square centimeter to a non-woven fabric transfer delay layer bonded with polyolefin yarn having a basis weight of between about 25 grams per square meter and 35 grams per square meter, adjacent to a retention layer comprising pulp and superabsorbent material.

18. The pad as claimed in claim 17, characterized in that said cover is creped by an amount of between about 25 percent and 40 percent and has a basis weight of between about 15 grams per square meter and 25 grams per meter square.

19. The pad as claimed in claim 17, characterized in that said fabric placed by air is made of pulp and thermoplastic fibers.

20. The pad as claimed in claim 17, characterized in that said fabric bonded with yarn is made of polypropylene fiber.

21. The pad as claimed in claim 17, characterized in that said creped cover is made of polypropylene fibers. SUMMARY A pad for female hygiene is provided comprising a cover adjacent to a capillary fabric having regions of an upper and lower capillarity, which is adjacent to a retaining layer. In a preferred embodiment, a spin-bonded and creped layer is used as the cover material and a co-perforated absorption / distribution layer and a transfer delay layer are the wicking fabric. Combining these improvements in an integrated absorbent system allows the successful management of variable flow management and the successful balance between the properties of absorption and desorption of the roof. The result is an improved multiple absorption performance and a clean and dry cover during use.