阅读说明：本技术 具有表面改性顶片的一次性吸收制品 (Disposable absorbent article with surface modified topsheet ) 是由 M.O.阿维尔斯 Y.吉扎夫 G.C.温宁 J.L.哈蒙斯 于 2018-06-28 设计创作，主要内容包括：公开了适于吸收和容纳身体流出物的一次性吸收制品。这些制品包括：开孔非织造顶片,该开孔非织造顶片具有身体表面和相背的衣服表面；底片；吸收芯；以及设置于顶片上的表面改性组合物。该组合物包含疏水性颗粒和疏水性粘结剂。(Disposable absorbent articles adapted to absorb and contain bodily exudates are disclosed. These articles include: an apertured nonwoven topsheet having a body surface and an opposing garment surface; a negative film; an absorbent core; and a surface modifying composition disposed on the topsheet. The composition comprises hydrophobic particles and a hydrophobic binder.)

1. A disposable absorbent article, comprising:

a. an apertured nonwoven topsheet having a body surface and an opposing garment surface;

b. a negative film;

c. an absorbent core disposed between the topsheet and the backsheet;

d. a surface modifying composition disposed on the body surface of the topsheet, the composition comprising hydrophobic particles and a hydrophobic binder; and

wherein the article exhibits a free fluid acquisition time of less than 30 seconds.

2. The disposable absorbent article of claim 1, wherein the article exhibits a free fluid acquisition time of less than 28 seconds, more preferably less than 20 seconds, most preferably less than 10 seconds.

3. The disposable absorbent article of claim 1 or 2, wherein the body surface has less than 3.5mm²The effective aperture area of.

4. The disposable absorbent article according to any one of the preceding claims, wherein the topsheet has a basis weight of from 10gsm to 40 gsm.

5. The disposable absorbent article according to any one of the preceding claims, wherein the topsheet exhibits a fiber roughness of from 1 μ ι η to 3.5 μ ι η.

6. The disposable absorbent article of any of the preceding claims, wherein the surface modification composition is applied to one or more of the front, middle, and back of the body surface of the topsheet in an amount from 0.1gsm to 3 gsm.

7. The disposable absorbent article according to any of the preceding claims, wherein the hydrophobic particles are selected from the group consisting of hydrophobically modified silicas, modified polyacrylates, polymethacrylates, acrylate-vinyl acetate copolymers, styrene acrylic copolymers, carboxylated styrene butadiene copolymers, and combinations thereof.

8. The disposable absorbent article of any of the preceding claims, wherein the hydrophobic binder is selected from the group consisting of hydrophobic silicones, hydrophobic aminosilicones, dimethicones, hydrophobic triglycerides, hydrogenated oil waxes, soy waxes, polyols, and combinations thereof.

9. The disposable absorbent article according to any of the preceding claims, wherein the article exhibits an average effective area% of less than or equal to 20%.

10. The disposable absorbent article of any of the preceding claims, wherein the article is selected from the group consisting of sanitary napkins, pantiliners, diapers, diaper pants, and incontinence pads.

Technical Field

The present invention relates to disposable absorbent articles adapted to absorb and contain body exudates.

Background

Disposable absorbent articles are a major commodity in households throughout the world due to their use by people of all ages. Infants and young children wear such articles to absorb urine and bowel movement. Young girls and women wear sanitary pads daily to treat vaginal secretions. These same classes of maiden and women rely on sanitary napkins every month as they go through their menstrual cycle, which requires their body to periodically discharge menses over the course of several days. Adult males and females, as they age, find themselves in need of incontinence pads or pants and are unable to control their desire to urinate. It is therefore apparent that people, regardless of age, often rely on disposable absorbent articles to assist them in managing the discharge of bodily fluids. In the case of infants and young children, discretion is not necessarily an important factor for articles that perform well during wear, as such wearers rely on adults to change them, and if the diaper of an infant or young child is found to be damaged, their image is not stained. In practice, this is desirable and even encouraged by parents and caregivers. Adult wearers, on the other hand, favor their discretion when wearing such articles, and preferably such articles are not noticed by those around them, and ideally the wearers themselves will forget that they are wearing such articles.

Despite this difference between two different wearer populations, they (and their caregivers) have a common expectation for the product to feel dry during wear and, even more importantly, during use. Drying during wear and use equates to comfort and can translate into increased confidence in the wearer that the benefit can be appreciated. Typically, the groin area that is contacted and/or covered by an absorbent article during use may experience some warmth and moisture as such articles appear thicker and sometimes less breathable. These conditions only get worse when they are subjected to bodily fluids. To overcome this eventuality of fluid management, it is preferred that the absorbent article absorbs fluid rapidly shortly after being expelled from the body. Many manufacturers of such products are working to improve the absorbent material contained therein to increase the acquisition rate of the product, which can result in the wearer not experiencing a wet feeling after insult. These improvements are directed to changes in the materials used for the topsheet, secondary topsheet, acquisition layer, or core of the product. While many such products rapidly acquire the discharged fluid, these same products have not addressed the tendency of the discharged fluid to spread readily over the body contacting surface of the product. Such diffusion also contributes to certain wet feel experiences.

In view of the recognition of this additional contribution to the undesirable wet feel wearer experience after insult, there appears to be a need for improvements in disposable absorbent articles resulting in a minimization of the spread of discharged fluids on the body contacting surface.

Disclosure of Invention

The disposable absorbent article according to the present invention is well suited for providing a minimized skin contact area for fluid discharge during wear. In one embodiment, a disposable absorbent article includes: an apertured nonwoven topsheet having a body surface and an opposing surface; a negative film; an absorbent core disposed between the topsheet and the backsheet; and a surface modifying composition disposed on the body surface of the topsheet, wherein the composition comprises hydrophobic particles and a hydrophobic binder; and wherein the article exhibits a free fluid acquisition time of less than 30 seconds.

In another embodiment, the present invention is directed to a disposable absorbent article comprising: an apertured nonwoven topsheet having a body surface and an opposing garment surface; a negative film; an absorbent core disposed between the topsheet and the backsheet; a surface modifying composition disposed on the body surface of the topsheet, the composition comprising hydrophobic particles and a hydrophobic binder; and wherein the article exhibits an average effective area% of less than 20%.

Drawings

While the specification concludes with claims particularly pointing out and distinctly claiming the subject matter which is regarded as forming the present invention, it is believed that the invention will be better understood from the following description which is taken in conjunction with the accompanying drawings in which like reference numerals identify substantially identical elements and in which:

fig. 1 shows a perspective view of a disposable absorbent article (i.e., sanitary napkin) of the present invention.

Fig. 2 shows a cross-sectional view of the sanitary napkin of fig. 1.

FIG. 3 shows a perspective view of a permeate sheet that can be used to determine the time of collection, as measured in certain embodiments of the present invention.

Fig. 4A shows a top view of the permeate sheet of fig. 3.

Fig. 4B shows the test fluid reservoir of the permeate sheet of fig. 3.

Fig. 5A shows a cross-sectional view along the longitudinal axis (a-a) of the permeate sheet of fig. 3.

Fig. 5B shows a cross-sectional view along the transverse axis (B-B) of the permeate sheet of fig. 3.

Detailed Description

As used herein, the term "absorbent core" refers to an absorbent core having one or more absorbent core layers. Each absorbent core layer is capable of acquiring and transporting or retaining fluids.

As used herein, the term "apertured" refers to a nonwoven that has been subjected to mechanical means that results in weakened patterned sites on the nonwoven surface. The weakened portions may be partially or fully opened.

As used herein, the term "bicomponent fiber" refers to a fiber formed from at least two different polymers extruded from separate extruders but spun together to form one fiber. Bicomponent fibers are also sometimes referred to as conjugate fibers or multicomponent fibers.

As used herein, the term "biconstituent fibers" refers to fibers which have been formed from at least two polymers extruded from the same extruder as a blend. Biconstituent fibers do not have the various polymer components arranged in relatively constantly positioned distinct zones across the cross-sectional area of the f-fiber and the various polymers are usually not continuous along the entire length of the fiber, but instead usually form fibrils which start and end at random. Biconstituent fibers are sometimes also referred to as multiconstituent fibers.

As used herein, the term "disposable" describes articles that are not intended to be laundered or otherwise restored or reused as an article (i.e., they are intended to be discarded after a single use and, possibly, to be recycled, composted or otherwise disposed of in an environmentally compatible manner). The absorbent article according to the invention may be, for example, a sanitary napkin or a panty liner or an adult incontinence article or a baby diaper or a wound dressing. The invention will be described herein in the context of a typical absorbent article, such as a sanitary napkin. Typically, such articles may comprise a liquid permeable topsheet, a backsheet, and an absorbent core intermediate the topsheet and the backsheet.

As used herein, the term "nonwoven web" refers to a web having a sandwiched structure of individual fibers or threads, but not in a repeating pattern as in a woven or knitted fabric, which generally does not have randomly oriented fibers. Nonwoven webs or fabrics have been formed from many processes such as, for example, meltblowing processes, spunbonding processes, spunlacing processes, hydroentangling processes, air-laying processes, and bonded carded web processes, including carded thermal bonding processes. The basis weight of nonwoven fabrics is typically expressed in grams per square meter (gsm). The basis weight of the laminate web is the combined basis weight of the component layers and any other added components. Fiber diameter is typically expressed in microns; fiber size, which may also be expressed in denier, is the unit of weight per fiber length. Depending on the end use of the web, the basis weight of laminate webs suitable for use in the articles of the present invention may range from 10gsm to 100 gsm.

While particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention.

The disposable absorbent article of the present invention, particularly a sanitary napkin, a sanitary pant, a diaper, or a training pant, provides for a reduced flow of fluid on the body-facing surface of the article during use, once body fluids are discharged onto the surface. In particular, it is envisaged that the articles of the invention exhibit increased dryness after insult, largely due to the confinement of fluid within a defined area of the product. For the purposes of this disclosure, reference will be made to a sanitary napkin, a diaper, a disposable absorbent article, or an absorbent article. However, the present invention can be used in the form of a variety of disposable absorbent articles including, but not limited to, sanitary napkins, pantiliners, catamenial pads, training pants, and the like.

In designing disposable absorbent articles, such as sanitary napkins or diapers, one aspect of the product that is of interest to designers is ensuring that sufficient absorbency is present. It goes without saying that for the article to be perceived as functional, it must be able to withstand the insults of bodily exudates it is subjected to. Closely related to this major capacity is the following product capacity, which is often of little concern: diffusion of body exudates is minimized after insult of the body facing surface of the article. It is therefore desirable to somehow reduce the intermolecular forces between the fluid and the body contacting surface of the article (commonly referred to as the topsheet). This can be achieved in various ways. For example, the surface energy of the topsheet material may be reduced only by the type of topsheet material used (e.g., hydrophobic, hydrophilic, or fully hydrophobic), or via application of a hydrophobic or hydrophilic coating onto such a topsheet. Alternatively, the surface topography of the topsheet material of such articles may be mechanically altered. This may be achieved by grinding, embossing or perforating the material.

In contrast to these past approaches, the inventors of the present invention sought to modify the surface properties of the topsheet material to minimize the diffusion or flow of any contacting fluid to significantly smaller areas than would normally be encountered in a common drainage event. This minimization of spreading or spreading is facilitated by the superior absorption of any contact fluids by the underlying layers, which ultimately provides a drier feel to the wearer after insult. The present inventors have found that certain features of disposable absorbent articles can provide these benefits which have not actually been delivered to the consumer in the same manner by existing products.

Fig. 1 shows a disposable absorbent article of the present invention, which in this example is a sanitary napkin 10. The sanitary napkin 10 comprises a generally elongated shape. The shape may take the form of a rectangle, oval, hourglass, offset hourglass (one end wider than the opposite end and a middle portion between the ends narrower), etc. An important attribute of the shape of the sanitary napkin 10 is that it provides sufficient coverage and protection to the user. However, any suitable shape may be utilized. The sanitary napkin 10 can be symmetric about the longitudinal axis 50 or asymmetric about the longitudinal axis 50. Similarly, the sanitary napkin 10 may be symmetric about the transverse axis 60 or asymmetric about the transverse axis 60. The sanitary napkin 10 comprises an apertured nonwoven topsheet 20 which further comprises a front portion 26, a back portion 28, and a central portion 27 disposed therebetween. Each of these portions may be equal in length along the topsheet and thus along the entire length of the sanitary napkin. Alternatively, the front and rear portions may be longer than the middle portion, or the middle portion may be longer than each of the front and rear portions.

Fig. 2 shows a cross-section of the sanitary napkin 10 of fig. 1. The sanitary napkin 10 includes an apertured nonwoven topsheet 20. The topsheet 20 has a body surface 22 which contacts the body of the user during wear. The topsheet 20 also has an opposing garment surface 24 which faces away from the user's body during wear. The absorbent core 30 is disposed below the topsheet 20. The backsheet 40 is disposed below the absorbent core 30 such that the core 30 is disposed between the topsheet 20 and the backsheet 40. The backsheet 40 is typically the outermost layer of the article, which is often the layer that is attached or joined to the undergarment. The attachment or engagement may be achieved by applying an adhesive, hook and loop fasteners, crimping, ultrasonic bonding, or heat sealing. It should be noted that additional layers may be included in the sanitary napkin, in particular between the topsheet 20 and the backsheet 40, but it should be noted that these layers are separate and apart from the absorbent core 30. Suitable additional layers may include secondary topsheets, acquisition layers, additional distribution layers above the above discussed layers, as will be discussed below, and other useful layers. In this embodiment, the secondary topsheet 25 is disposed beneath the topsheet 20 and above the body surface 31 of the core 30. In certain embodiments, the secondary topsheet (also referred to as "STS") has a greater length and width than the absorbent core 30.

Applicants will now provide a more detailed description of the various components of the disposable absorbent articles contemplated herein.

Topsheet

The apertured nonwoven topsheet 20 of the sanitary napkin 10 is positioned adjacent the body surface 31 of the absorbent core 30 and may be joined thereto and to the backsheet 40 by attachment methods such as those known in the art. Suitable attachment methods will be described with reference to joining the backsheet 40 to the absorbent core 30. The topsheet 20 and the backsheet 40 may be joined directly to each other along the periphery of the sanitary napkin and may be joined together indirectly by joining them directly to the absorbent core 30 or may be joined together indirectly by additional optional layers within the product, such as a secondary topsheet spanning the entire area or a partial area of the article. Such indirect or direct engagement may be accomplished by these same attachment methods known in the art.

The topsheet should be compliant, soft feeling, and non-irritating to the wearer's skin. Suitable topsheet materials include liquid pervious materials that are oriented toward and contact the body of the wearer, allowing bodily discharges to pass rapidly therethrough without allowing fluid to pass back through the topsheet to the skin of the wearer. Suitable topsheets can be made from a variety of nonwoven materials. Non-limiting examples of woven and nonwoven materials suitable for use as the topsheet include fibrous materials made from natural fibers, modified natural fibers, synthetic fibers, or combinations thereof. These fibrous materials may be hydrophilic or hydrophobic, but preferably the topsheet is hydrophobic or treated to be hydrophobic. As an option, one or more portions of the topsheet can be treated to be hydrophilic by using any known method for making topsheets comprising hydrophilic components. These portions may be located in one or more of the front, center, or back regions of the topsheet. Methods describing processes for treating topsheets with surfactants are disclosed in U.S. Pat. Nos. 4,988,344 and 4,988,345, both issued to Reising et al, 1/29 1991. The topsheet can have hydrophilic fibers, hydrophobic fibers, or a combination thereof.

The topsheet may comprise one or more layers. In certain embodiments, the topsheet may be a single layer, a bi-layer, a tri-layer, or even more layers. Where there is more than one topsheet layer, any additional layers are referred to herein in turn, assuming that the monolayer is the first topsheet layer. In other words, the subsequent layer is referred to as a second, third, or similar topsheet layer. In the case of multiple topsheet layers, the layers can be joined in a variety of ways, including melt bonding, gluing, ring rolling, and the like. In its laminate form, subsequent layers of the topsheet may also be apertured through the first topsheet layer.

A particularly suitable topsheet comprises staple length polypropylene fibers having a denier of about 1.5, such as the Hercules type 151 polypropylene sold by Hercules, inc. (Wilmington, Del). As used herein, the term "staple length fibers" refers to those fibers having a length of at least about 15.9mm (0.62 inches). Another suitable web for use as a topsheet is a nonwoven, i.e., a 25gsm 70%/30% polyethylene/polypropylene bicomponent (commercially available from Pegas Nonwovens or Fibertex Nonwovens). Such webs may be over-bonded with a pattern formed as a result of the mating rolls providing selective weakening of the web, as described in U.S. patent No. 5,916,661 to Benson et al, 6-29 1999. The patterning mechanism may also be relied upon to form apertures in the topsheet. In such cases of the present invention, the mating rolls may be set to a depth of engagement (DOE) that is appropriately correlated with the desired hole size. In some cases, the DOE may target 0.045 inches to 0.085 inches, and a desired average DOE is about 0.065 inches. In these cases, there are bond sizes (0.1 inch by 0.010 inch) and spacing (e.g., rows with 0.12 inch horizontal spacing between bonds, and 0.060 inch offset with no vertical spacing between rows). These bonds are referred to as melt stabilization zones and form the pores of the open-celled nonwoven when activated by the ring rolling process.

When the topsheet comprises a nonwoven web, the nonwoven may be produced by any known process for making nonwoven webs, non-limiting examples of such processes include spunbonding, carding, wet-laying, air-laying, meltblowing, needle punching, mechanical winding, thermo-mechanical winding, and hydroentangling. The nonwoven material may be resistant to compression, as described in U.S. patent 7,785,690, published on 31/8/2010. The nonwoven web may have loops as described in U.S. patent 7,838,099, published on 11/23/2010.

Other suitable nonwoven materials include low basis weight nonwovens, i.e., having about 10g/m²To about 40g/m²A nonwoven of basis weight. An example of such a nonwoven material is commercially available under the trade name P-8 from Veratec, Inc, a division of the International Paper Company, located in Walpole, Mass. Other useful nonwoven materials are described in U.S. patents 5,792,404 and 5,665,452.

The topsheet can include tufts, such as U.S. patent 8,728,049 issued on 5/20/2014; U.S. Pat. No. 7,553,532, published on 30/6/2009; us patent 7,172,801, published on 6.2.2007; or U.S. patent 8,440,286, published 5/14/2013. The topsheet may have a reverse textured web as described in U.S. patent 7,648,752, published on 1/19/2010. Clusters are also described in U.S. patent 7,410,683 published at 8/12/2008.

The topsheet may have a pattern of discrete hair-like fibrils, as described in U.S. patent 7,655,176, published at 2.2010, or U.S. patent 7,402,723, published at 22.7.2008.

The topsheet may include one or more structurally modified zones, as described in U.S. patent 8,614,365, published 24.12.2013. These zones may coincide with one or more of the anterior, medial and posterior portions. The topsheet may have one or more out-of-plane deformations as described in U.S. patent 8,704,036 issued on 4-22/2014. The primary topsheet may have a masking composition, as described in U.S. patent 6,025,535 issued on 2/15/2000.

Another suitable topsheet or topsheet combined with a secondary topsheet may be formed from a three-dimensional substrate such as U.S. patent application serial No. 15/453,997 filed 3/9 of 2017 in the name of Jill m. The three-dimensional substrate has a first surface, a second surface, a land area, and further includes a three-dimensional protrusion extending outwardly from the second surface of the three-dimensional substrate, wherein the three-dimensional protrusion is surrounded by the land area. The substrate is a laminate comprising at least two layers in a face-to-face relationship, the second layer is a tissue layer facing outwardly from the second surface of the three-dimensional substrate, and the tissue layer comprises at least 80% pulp fibers by weight of the tissue layer.

The topsheet may comprise one or more layers, such as a spunbond-meltblown-spunbond (SMS) material. The apertured topsheet may have any suitable three-dimensional feature and/or may have a plurality of embossments (e.g., bond patterns). The apertures of the topsheet can be formed by overbonding the material and then rupturing the overbonds by ring rolling, as disclosed in U.S. patent 5,628,097 to Benson et al, 5-13, 1997. Additional lateral extensibility in either of the topsheet and/or backsheet and the intermediate layer (the combination of which may be referred to as the "chassis" of the product) can be provided in a variety of ways. For example, either the topsheet or the backsheet may be pleated by any of a number of known methods. Alternatively, all or a portion of the chassis (including the topsheet and backsheet) may be made from a formed web of material or a formed laminate of webs of material, such as those described in U.S. patent 5,518,801 to Chappell et al, 5/21, 1996. Such formed webs of material include distinct laterally extending regions in which the original material has been altered by embossing or another method of deformation to form a pattern of generally longitudinally oriented alternating ridges and valleys. The formed web material also includes laterally extending unaltered regions located between the laterally extending altered regions

The apertures of the topsheet may be modified by modifying the formation of the patterned areas of weakness imparted thereinThe device is realized. Such forming devices for deforming a generally planar web into a three-dimensional structure are known for use in the present invention to modify an absorbent material as manufactured into an absorbent material having a relatively high permeability without a significant corresponding capillary pressure drop. The forming device may comprise a pair of intermeshing rolls, typically steel rolls having intermeshing ridges or teeth and grooves. However, it is contemplated that other means for achieving shaping may be utilized, such as the deforming roll and cord (cord) arrangement disclosed in U.S. patent publication 2005/0140057, published 6/30 2005. Accordingly, all disclosure herein of a pair of rolls is considered equivalent to a roll and a cord, and the claimed arrangement detailing two intermeshing rolls is considered equivalent to an intermeshing roll and a cord, wherein the cord serves as a ridge of a mating intermeshing roll. In one embodiment, the pair of intermeshing rolls of the invention can be considered equivalent to a roll and intermeshing elements, where the intermeshing elements can be another roll, a cord, a plurality of cords, a belt, a flexible web, or a belt. Likewise, other known forming techniques, such as creping, necking/consolidation, corrugating, embossing, snap-off (button break), hot-pin stamping, etc., are believed to produce absorbent materials having a degree of relatively high permeability without a corresponding reduction in capillary pressure. Forming methods using rolls include "ring rolling", "SELF", or "SELF' ing" processes, where SELF represents a structured elastic-like film (R) ((R))StructuralElasticLikeFilm), such as "microstructured elastic-like film" and "rotary blade aperturing" (RKA), which are described in us patent 7,935,207 to Zhao et al, 5/3/2011.

Suitable hole patterns and mechanisms for accomplishing the same are also detailed in U.S. patent publications 2016/0129661 and 2016/0129662, published in 2016, 5, 12. The apertures of the nonwoven topsheet can be of a variety of shapes including, but not limited to, rectangular, circular, oblong, triangular, slit-like, and the like. An important aspect of the topsheet is the effective aperture area of its body surface. Without being limited by theory, the inventors surmise that the size of the aperture may be in the topsheetVariation on body surface, but topsheet exhibiting less than 3.5mm²Is critical. In particular, the effective aperture area is greater than 1.8mm²、1.9mm²、2mm²、or 2.1mm²and less than 3.5mm²、3.4mm²、3.2mm²、3mm²、2.8mm²、2.6mm²Or 2.4mm². This is true because if the collection of apertures in one or more portions of the topsheet is too narrow or small, they will not allow the article to properly and usefully acquire insult fluid when brought together. Such a construction would likely result in the accumulation of insult fluid on the body surface of the topsheet, which is absolutely undesirable. On the other hand, if the collection of apertures is too large or quite large, the topsheet becomes ineffective in acting as a barrier to the wearer from fluids that have been absorbed by any underlying layers. This effect may eventually lead to a wet feel for the wearer after an insult. In addition, in combination with the desired effective aperture area, it is desirable that the topsheet also exhibit an average effective area% of less than or equal to 20%, 18%, 16%, 14%, 12%, or 11%. This ensures that the area open to the underlying layer (e.g., the secondary topsheet or acquisition layer) is not so large in one or more of the front, middle, or back of the topsheet that the concentration of apertures allows for maintenance of a barrier between the wearer and absorbed fluids in the article after insult.

The overall construction of the topsheet (including the application of the surface modifying composition and the apertures described below) results in a topsheet that is: such fluids are more capable of transferring into the underlying layers of a disposable absorbent article or product upon contact with a fluid, such as Artificial Menses (AMF). This ability to receive and subsequently transfer fluid via absorption by the underlying layer is demonstrated in a number of ways. For example, the disposable absorbent articles of the present invention exhibit a reduced interfacial fluid area of the topsheet and underlying layers (typically the STS or acquisition layer). The area of the interface fluid is less than 300mm²、280mm²、260mm²Or 240mm². The measurement of interfacial fluid area is described in the test methods section below. The articles of the present invention also exhibit a free fluid acquisition time of less than 30 seconds. Free fluid acquisition timeIndicating the overall ability of the article to draw fluid away from the skin surface of the wearer of the article. The faster the free fluid acquisition time, the better the performance or perceived dryness of the article by the wearer. For example, the free-fluid acquisition time of the article may be less than 28s, 26s, 24s, 22s, 20s, 18s, 16s, 14s, 12s, 10s, 8s, or even 6 s. However, this metric must be balanced against other metrics. For example, the topsheet of the article of the present invention also exhibits a reduced or minimal topsheet stain area upon removal of the topsheet from the article, after insult to the body surface. The removed topsheet stain area is intended to be smaller than that present on an untreated topsheet or a topsheet treated with a composition different from those discussed and claimed herein. The stained area of the top sheet is less than 30mm²、25mm²、20mm²、15mm²、13mm²、12mm²Or 10mm². The method for measuring the resulting topsheet stain area on the removed topsheet is detailed in the test methods section below. Fiber roughness values are also another measure useful herein to quantify the change in topographical features of the nonwoven fiber surface area that is increased by the application of the surface modifying composition. Ideally, the fiber roughness value is increased relative to an untreated nonwoven. It is contemplated that the fiber roughness values of the present invention range from 1 μm to about 3.5 μm, 3 μm, 2.5 μm, or even 2 μm. This method is detailed in the test methods section below. The inventors have determined that the ultimate measure that can be used to distinguish the articles of the present invention from other disposable absorbent articles is the stain chroma value. The measurement is indicative of the intensity of the insult stain observed by the wearer or user. The method used to determine this value is also detailed in the test methods section below.

Surface modification composition

The surface modifying composition 35 is disposed on the body surface 22 of the topsheet 20. The composition is intended to impart specific characteristics to the topsheet, including minimizing the spreadability and adherence of fluid thereon. The inventors have found that applying the composition to the topsheet drives liquids introduced into the respective article or product to a smaller area, where such fluids are then subsequently absorbed by the underlying layer. The surface modification composition can be disposed on the body surface of the topsheet in a variety of ways including, but not limited to, slot coating, spraying, wetting, dipping, printing, or any other application method suitable and known in the art. The composition may be applied to one or more of the front, middle and/or back regions. For example, in certain embodiments and product types, if the sanitary napkin is intended to be worn by an adult consumer during the day, for example, it may be desirable to treat only the central portion of the product. In contrast, in the case where the product may be a training pant, baby diaper, or adult overnight sanitary napkin, it is advantageous to optimize the performance of the topsheet by applying the surface modifying composition along the entire length of the product so that the front, middle, and back portions of the topsheet are treated.

The surface modification composition comprises hydrophobic particles and a hydrophobic binder. The particles and binder are present in the composition in a ratio of 4:1 to 1:4, 2:1 to 1:2, or even 1: 1. The compositions are applied to the topsheet in an amount of 0.1gsm, 0.15gsm, or 0.2gsm to 0.5gsm, 0.75gsm, 1gsm, 1.5gsm, 2gsm, 2.5gsm, or even 3gsm on one or more of the front, middle, and back of the body surface of the topsheet. The compositions provided in these ratios of binder to particle provide optimal conditions for the body surface 22 of the topsheet 20 to exhibit minimal spreading and adherence of fluid thereon.

The inventors have found that applying the composition to the topsheet drives liquids introduced into the respective article or product to a smaller area, where such fluids are then subsequently absorbed by the underlying layer. In particular, the surface modification composition results in a reduced spreading area on the topsheet and increased absorption by the underlying layers such that the area of stain observed on the topsheet after removal is measured to be less than 30mm². In other embodiments, the observed topsheet stain area is less than 25mm²、20mm²、15mm²、10mm²Or less than 8mm². In contrast, when the binder to particle ratio is outside the ratio of 4:1 to 1:4, the same observed stain area is significantly increased. The result is highly undesirable to the consumer or wearer。

The surface modifying composition can be disposed on the body surface of the topsheet in a variety of ways including, but not limited to, slot coating, spraying, wetting, dipping, printing, or any other application method suitable and known in the art. The composition may be applied to one or more of the front, middle and/or back regions. For example, in certain embodiments and product types, if the sanitary napkin is intended to be worn by an adult consumer during the day, it may be desirable to treat only the central portion of the product. In contrast, in the case where the product may be a training pant, baby diaper, or adult overnight sanitary napkin, it is advantageous to optimize the performance of the topsheet by applying the surface modifying composition along the entire length of the product so that the front, middle, and back portions of the topsheet are treated.

Suitable hydrophobic particles are selected from the group consisting of hydrophobically modified silicas, modified polyacrylates, polymethacrylates, acrylate-vinyl acetate copolymers, styrene acrylic copolymers, carboxylated styrene-butadiene copolymers, and combinations thereof. Exemplary particles useful in the present invention are listed in table 1 below. These particles may be used alone or in combination with each other, or with other particulate materials of similar properties, which in combination provide the desired surface properties to the nonwoven.

Table 1: particle list

With respect to hydrophobic binders, such materials can be selected from the group consisting of polydimethylsiloxanes, amino-functional siloxanes, dimethylsiloxanes, polyisobutylenes, hydrogenated triglycerides, hydrogenated oil waxes (including soy wax), and other polyols, and combinations thereof.

In one embodiment of the invention, the hydrophobic binder is an organopolysiloxane having the formula:

M_wD_xT_yQ_z

wherein:

m is selected from [ SiR₁R₂R₃O_1/2]、[SiR₁R₂G₁O_1/2]、[SiR₁G₁G₂O_1/2]、[SiG₁G₂G₃O_1/2]And combinations thereof;

d is selected from [ SiR₁R₂O_2/2]、[SiR₁G₁O_2/2]、[SiG₁G₂O_2/2]And combinations thereof;

t is selected from [ SiR₁O_3/2]、[SiG₁O_3/2]And combinations thereof;

Q＝[SiO_4/2]；

w is an integer from 1 to about (2+ y +2 z);

x is an integer from about 5 to about 15000;

y is an integer from 0 to about 98;

z is an integer from 0 to about 98;

R₁、R₂and R₃Each independently selected from H, OH, C₁-C₃₂Alkyl radical, C₁-C₃₂Substituted alkyl, C₅-C₃₂Or C₆-C₃₂Aryl radical, C₅-C₃₂Or C₆-C₃₂Substituted aryl, C₆-C₃₂Alkylaryl group, C₆-C₃₂Substituted alkylaryl, C₁-C₃₂Alkoxy radical, C₁-C₃₂Substituted alkoxy, C₁-C₃₂Alkylamino and C₁-C₃₂Substituted alkylamino;

and wherein at least one of M, D and T incorporates at least one portion G₁、G₂Or G₃And is and

G₁、G₂and G₃Are identical or different moieties, each having the formula:

wherein:

x comprises a divalent group selected from: c₁-C₃₂Alkylene radical, C₁-C₃₂Substituted alkylene (optionally interrupted by a heteroatom selected from P, N and O), C₅-C₃₂Or C₆-C₃₂Arylene radical, C₅-C₃₂Or C₆-C₃₂Substituted arylene, C₆-C₃₂Arylalkylene radical, C₆-C₃₂Substituted arylalkylene radical, C₁-C₃₂Alkylene amino group, C₁-C₃₂Substituted alkyleneamino, ring-opened epoxide and ring-opened glycidol;

n is a nitrogen atom;

each R₄And each is independently selected from H,

C₁-C₃₂Alkyl radical, C₁-C₃₂Substituted alkyl, C₅-C₃₂Or C₆-C₃₂Aryl radical, C₅-C₃₂Or C₆-C₃₂Substituted aryl, C₆-C₃₂Alkylaryl and C₆-C₃₂A substituted alkylaryl group;

wherein

E comprises the same or different divalent groups selected from: c₁-C₃₂Alkylene radical, C₁-C₃₂Substituted alkylene, alkylene optionally doped with a heteroatom selected from P, N and O, C₅-C₃₂Or C₆-C₃₂Arylene radical, C₅-C₃₂Or C₆-C₃₂Substituted arylene, C₆-C₃₂Arylalkylene radical, C₆-C₃₂Substituted arylalkylene radical, C₁-C₃₂Alkoxy radical, C₁-C₃₂Substituted alkoxy, C₁-C₃₂Alkylene amino group, C₁-C₃₂Substituted alkyleneamino, heterocyclic ring systemsCyclic epoxides and ring-opened glycidyl groups;

R₅independently selected from H, C₁-C₃₂Alkyl radical, C₁-C₃₂Substituted alkyl, C₅-C₃₂Or C₆-C₃₂Aryl radical, C₅-C₃₂Or C₆-C₃₂Substituted aryl, C₆-C₃₂Alkylaryl and C₆-C₃₂A substituted alkylaryl group; or R₅Comprising one or more M_wD_xT_yQ_zA moiety;

and wherein at least one R5 comprises at least one M_wD_xT_yQ_zA moiety;

and wherein

m is an integer independently selected from 2 to 100,

n is an integer independently selected from 1 or 2,

and when there is an organopolysiloxane moiety G₁、G₂、G₃When part is positively charged, A^-tIs one or more suitable charge-balancing anions such that all of the one or more charge-balancing anions A present^-tAnd kA^-tG of the total charge and organopolysiloxane moiety₁、G₂Or G₃The net charge of the segments is equal and opposite.

Those of ordinary skill in the art will understand that:

a is the anionic counterion of the positively charged organopolysiloxane,

t is the charge of any individual counterion, and

k is the coefficient of any such counterion

Such that the sum of the counterions is neutral to the net charge of the positively charged organopolysiloxane.

In one embodiment, the block cationic organopolysiloxane has the formula:

or

Or

Wherein

D is [ SiR₁R₂O_2/2]，

x is an integer independently selected from about 40 to about 1000,

R₁、R₂and independently selected from H, OH, C₁-C₃₂Alkyl radical, C₁-C₃₂Substituted alkyl, C₅-C₃₂Or C₆-C₃₂Aryl radical, C₅-C₃₂Or C₆-C₃₂Substituted aryl, C₆-C₃₂Alkylaryl group, C₆-C₃₂Substituted alkylaryl, C₁-C₃₂Alkoxy radical, C₁-C₃₂A substituted alkoxy group, which is a substituted alkoxy group,

wherein

X comprises a divalent group selected from: c₁-C₃₂Alkylene radical, C₁-C₃₂Substituted alkylene (optionally interrupted by a heteroatom selected from P, N and O), C₅-C₃₂Or C₆-C₃₂Arylene radical, C₅-C₃₂Or C₆-C₃₂Substituted arylene, C₆-C₃₂Arylalkylene radical, C₆-C₃₂Substituted arylalkylene radical, C₁-C₃₂Alkylene amino group, C₁-C₃₂Substituted alkyleneamino, ring-opened epoxide and ring-opened glycidol;

R₄independently selected from H,

C₁-C₃₂Alkyl radical, C₁-C₃₂Substituted alkyl, C₅-C₃₂Or C₆-C₃₂Aryl radical, C₅-C₃₂Or C₆-C₃₂Substituted aryl, C₆-C₃₂Alkylaryl and C₆-C₃₂A substituted alkylaryl group;

n is a nitrogen atom;

R₅independently selected from H, C₁-C₃₂Alkyl radical, C₁-C₃₂Substituted alkyl, C₅-C₃₂Or C₆-C₃₂Aryl radical, C₅-C₃₂Or C₆-C₃₂Substituted aryl, C₆-C₃₂Alkylaryl and C optionally interrupted by a heteroatom selected from P, N and O₆-C₃₂Substituted alkylaryl, C₁-C₃₂Alkoxy radical, C₁-C₃₂Substituted alkoxy, C₁-C₃₂Alkylamino, or C₁-C₃₂Substituted alkylamino;

e comprises the same or different divalent groups selected from: c₁-C₃₂Alkylene radical, C₁-C₃₂Substituted alkylene, alkylene optionally doped with a heteroatom selected from P, N and O, C₅-C₃₂Or C₆-C₃₂Arylene radical, C₅-C₃₂Or C₆-C₃₂Substituted arylene, C₆-C₃₂Arylalkylene radical, C₆-C₃₂Substituted arylalkylene radical, C₁-C₃₂Alkoxy radical, C₁-C₃₂Substituted alkoxy, C₁-C₃₂Alkylene amino group, C₁-C₃₂Substituted alkyleneamino, ring-opened epoxide and ring-opened glycidyl;

m is an integer independently selected from 2 to 100,

n is an integer independently selected from 1 or 2,

f is an integer of 2 to about 50, and

A^-tis one or more suitable charge-balancing anions such that all of the one or more charge-balancing anions A present^-tAnd kA^-tIs equal toNet charge on the block cationic organopolysiloxane and vice versa.

In one embodiment, A^-tSelected from the group consisting of Cl-, Br-, I-, methosulfate, tosylate, carboxylate, phosphate, hydroxide, acetate, formate, carbonate, nitrate, and combinations thereof.

In one embodiment, the block cationic organopolysiloxane has the following structure:

or

Or

Wherein

D is [ SiR₁R₂O_2/2]，

x is an integer independently selected from about 40 to about 1000,

R₁、R₂and independently selected from H, OH, C₁-C₃₂Alkyl radical, C₁-C₃₂Substituted alkyl, C₅-C₃₂Or C₆-C₃₂Aryl radical, C₅-C₃₂Or C₆-C₃₂Substituted aryl, C₆-C₃₂Alkylaryl group, C₆-C₃₂Substituted alkylaryl, C₁-C₃₂Alkoxy radical, C₁-C₃₂A substituted alkoxy group, which is a substituted alkoxy group,

wherein

X comprises a divalent group selected from: c₁-C₃₂Alkylene radical, C₁-C₃₂Substituted alkylene (optionally interrupted by a heteroatom selected from P, N and O), C₅-C₃₂Or C₆-C₃₂Arylene radical, C₅-C₃₂Or C₆-C₃₂Substituted arylene, C₆-C₃₂Arylalkylene radical, C₆-C₃₂Substituted arylalkylene radical, C₁-C₃₂Alkylene amino group, C₁-C₃₂A substituted alkyleneamino group;

R₄independently selected from H,

C₁-C₃₂Alkyl radical, C₁-C₃₂Substituted alkyl, C₅-C₃₂Or C₆-C₃₂Aryl radical, C₅-C₃₂Or C₆-C₃₂Substituted aryl, C₆-C₃₂Alkylaryl and C₆-C₃₂A substituted alkylaryl group;

n is a nitrogen atom;

R₅independently selected from H, C₁-C₃₂Alkyl radical, C₁-C₃₂Substituted alkyl, C₅-C₃₂Or C₆-C₃₂Aryl radical, C₅-C₃₂Or C₆-C₃₂Substituted aryl, C₆-C₃₂Alkylaryl and C optionally interrupted by a heteroatom selected from P, N and O₆-C₃₂Substituted alkylaryl, C₁-C₃₂Alkoxy radical, C₁-C₃₂Substituted alkoxy, C₁-C₃₂Alkylamino radical, C₁-C₃₂Substituted alkylamino;

e comprises the same or different divalent groups selected from: c₁-C₃₂Alkylene radical, C₁-C₃₂Substituted alkylene, alkylene optionally doped with a heteroatom selected from P, N and O, C₅-C₃₂Or C₆-C₃₂Arylene radical, C₅-C₃₂Or C₆-C₃₂Substituted arylene, C₆-C₃₂Arylalkylene radical, C₆-C₃₂Substituted arylalkylene radical, C₁-C₃₂Alkoxy radical, C₁-C₃₂Substituted alkanesOxy radical, C₁-C₃₂Alkylene amino group, C₁-C₃₂Substituted alkyleneamino, ring-opened epoxide and ring-opened glycidyl;

m is an integer independently selected from 2 to 100,

n is an integer independently selected from 1 or 2,

f is an integer of 2 to about 50, and

A^-tis one or more suitable charge-balancing anions such that all of the one or more charge-balancing anions A present^-tAnd kA^-tIs equal to and opposite to the net charge on the block cationic organopolysiloxane.

For suitable polyols that can be used as hydrophobic binders, metathesized unsaturated polyol esters may be desired, including eleven Smooth CS-110, available from eleven Renewable Sciences, Inc (Woodridge, il. usa), or under the trade name DOW

Hy-3050 soy wax was purchased from Dow Corning (Midland Michigan USA). Additional exemplary metathesized unsaturated polyol esters and starting materials therefor are listed in U.S. patent applications 2009/0220443a1, 2013/0344012a1, and 2014/0357714a 1. Metathesized unsaturated polyol ester refers to the product obtained when one or more unsaturated polyol ester components are subjected to a metathesis reaction. Metathesis is a catalytic reaction involving the interchange of alkylene units between compounds containing one or more double bonds (i.e., olefinic compounds) via the formation and cleavage of carbon-carbon double bonds. Metathesis can occur between two identical molecules (often referred to as self-metathesis), and/or it can occur between two different molecules (often referred to as cross-metathesis).

Additional exemplary hydrophobic binders useful in the present invention are listed in table 2 below.

Table 2: list of hydrophobic binders

Tables 1 and 2 are not exhaustive, but show hydrophobic particles and hydrophobic binders that have been found to be useful in the present invention.

The surface modification composition may also include a solvent to aid in suspending the hydrophobic particles and the hydrophobic binder. Suitable solvents include, but are not limited to, water, ethanol, isopropanol, propylene glycol n-butyl ether, or any other volatile solvent. The resulting composition, once applied to the topsheet via spraying, dipping, wetting, printing, imparts a rougher topography to the topsheet. This altered topography of the topsheet results in a topsheet exhibiting a fiber roughness of about 1 μm to about 3.5 μm. In other embodiments, the fiber roughness is from 1 μm to 3 μm, from 1 μm to 2.5 μm, or from 1 to 2 μm.

Negative film

The backsheet 40 of the chassis may be positioned adjacent the garment-facing surface of the absorbent core 30 and may be joined thereto by attachment methods (not shown), such as those known in the art. For example, the backsheet 40 may be secured to the absorbent core 30 by a uniform continuous layer of adhesive, a patterned layer of adhesive, or a series of individual lines, spirals, or spots of adhesive. Alternatively, the attachment method may include the use of thermal bonding, pressure bonding, ultrasonic bonding, dynamic mechanical bonding, or any other suitable attachment method or combination of these attachment methods as known in the art. Forms of the present disclosure are also contemplated in which the absorbent core 30 is not joined to the backsheet 40, the topsheet 20, or both.

The backsheet 40 may be impervious or substantially impervious to liquids (e.g., urine) and may be manufactured from a thin plastic film, although other liquid impervious flexible materials may also be used. As used herein, the term "flexible" refers to materials that are compliant and readily conform to the general shape and contours of the human body. The backsheet 40 may prevent, or at least inhibit, exudates absorbed and contained by the absorbent core 30 from wetting articles of clothing, such as undergarments, that come into contact with the sanitary napkin 10. In some cases, the backsheet 40 may allow vapors to escape from the absorbent core 30 (i.e., breathable), while in other cases, the backsheet 40 may not allow vapors to escape (i.e., non-breathable). Accordingly, the backsheet 40 may comprise a polymeric film, such as a thermoplastic polyethylene film or a polypropylene film. A suitable material for the backsheet 40 is a thermoplastic film having a thickness of, for example, about 0.012mm (0.5 mil) to about 0.051mm (2.0 mils). Any suitable backsheet known in the art may be used in the present invention.

The backsheet 40 acts as a barrier to any absorbent bodily fluids that may pass through the absorbent core 30 to its garment surface, resulting in a reduced risk of soiling undergarments or other garments. Furthermore, if the wearer so desires, the barrier properties of the backsheet allow for manual removal of the interlabial absorbent article with a reduced risk of soiling of the hands. Preferred materials are soft, smooth, pliable liquid and vapor permeable materials that provide comfortable softness and conformability, and that produce low noise so that no objectionable noise is caused while exercising.

The backsheet 40 may comprise a wet laid fibrous assembly having a temporary wet strength resin incorporated therein as described in U.S. patent 5,885,265 issued to Osborn on 23.3.1999. The backsheet 40 may also be coated with a waterproof resinous material which renders the backsheet impervious to bodily fluids without hindering the diffusion of the adhesive material thereon.

Another suitable backsheet material is a polyethylene film having a thickness of about 0.012mm (0.5 mil) to about 0.051mm (2.0 mils). The backsheet may be embossed and/or matte finished to provide a more cloth-like appearance. In addition, the backsheet allows water vapor to escape from the absorbent core while still preventing body fluids from passing through the backsheet (i.e., the backsheet is breathable). A suitable material for the backsheet is a microporous polyethylene film available as number XBF-112W from Tredegar Corporation, Virginia, USA.

For stretchable but inelastic backsheets, one material that can be used is a hydrophobic, stretchable hydroentangled nonwoven material that is breathable (i.e., permeable to water vapor and other gases) and has a caliper of about 30g/m²To 40g/m²Formed from polyethylene terephthalate or polypropylene fibers.

For the elastic backsheet, an elastic film sold under the trademark EXX500 by Exxon Corporation may be used. Such an impermeable film is formed from an elastic base composition consisting of a styrene block copolymer. Another material that may be used for the elastic backsheet is a plastic film that has been subjected to a process that provides it with elastic-like properties without the need to attach elastic strands to the film, and may, for example, comprise a formed film as detailed in U.S. patent nos. 4,342,314 to Radel et al and 4,463,045 to Ahr et al, respectively.

Suitable breathable backsheets for use herein include all breathable backsheets known in the art. There are two types of breathable backsheets. A single layer breathable backsheet that is breathable and liquid impervious, and a backsheet having at least two layers that combine to provide breathability and liquid impermeability. Suitable single layer breathable backsheets for use herein include, for example, those described in U.S. patents 4,695,422, 4,839,216, 4,591,523, 3989867, 3,156,242 and WO 97/24097.

The backsheet may have two layers: a first layer comprising a breathable shaped film and a second layer comprising a breathable microporous film layer, as described in us patent 6,462,251. Suitable bi-or multi-layer breathable backsheets for use herein include those exemplified in U.S. patents 3,881,489, 4,341,216, 4,713,068, 4,818,600 and european patent publications 203821, 710471, 710472 and 793952.

The backsheet may be a relatively hydrophobic 18 grams per square meter (gsm) spunbond nonwoven web of 2 denier polypropylene fibers. The backsheet may also be a laminate.

The backsheet may be vapor permeable as described in U.S. patent 6,623,464 issued to Bewick-Sonntag at 23/9/2003 or U.S. patent 6,664439 issued to Arndt at 16/12/2003. The backsheet may be made of any material known in the art that is vapor permeable. The backsheet may be a microporous film, an apertured formed film or other polymeric film that is permeable to vapor or imparts vapor permeability properties thereto.

In other embodiments, the backsheet may be a nonwoven web having a basis weight of between 20gsm and 50 gsm. In one embodiment, the backsheet is a 23gsm spunbond nonwoven web of relatively hydrophobic 4 denier polypropylene fibers available from Fiberweb Neuberger under the trade designation F102301001. The backsheet may be coated with an insoluble liquid swellable material as described in U.S. patent No. 6,436,508 to ciammachella, 8/20/2002.

The backsheet 40 has a garment surface 42 and an opposing body surface 41. The garment surface of the backsheet comprises a non-tacky area and an adhesive area. The adhesive region may be provided by any conventional method. Pressure sensitive adhesives have generally been found to be very suitable for this purpose.

Absorbent core

The absorbent core 30 of the present invention may comprise any suitable shape including, but not limited to, oval, circular, rectangular, asymmetric, and hourglass shapes. For example, in some forms of the invention, the absorbent core 30 may have a contoured shape, e.g., narrower in the middle region than in the end regions. As another example, the absorbent core may have a tapered shape with a wider portion at one end region of the pad and tapering to a narrower end region at the other end region of the pad. The absorbent core 30 may have varying stiffness in the MD and CD.

The absorbent core 30 may include one or more absorbent layers. In certain embodiments, there are two absorbent layers, where there is a first absorbent layer and a second absorbent layer adjacent to the first absorbent layer. These materials are generally compressible, conformable, non-irritating to the wearer's skin, and capable of absorbing and retaining liquids such as urine and other certain body exudates, including menses. The first absorbent layer may comprise a first layer of absorbent material, which may be 100% or less superabsorbent polymer (SAP), such as 85% to 100% SAP, 90% to 100% SAP, or even 95% to 100% SAP, specifically including all 0.5% increments within the specified ranges and all ranges formed therein or thereby. The second absorbent layer may comprise a second layer of absorbent material, which may also be 100% or less SAP (including the ranges specified above). Alternatively, the first and/or second absorbent layers can each comprise cellulose, comminuted wood pulp, or the like in combination with an SAP. In addition, the absorbent core may also comprise only cellulosic material (also referred to as "air-laid" or "airfelt") as absorbent material. The absorbent core 30 may also include a carrier layer for either or both of the first and second absorbent layers. The support layer may also be a nonwoven web, which may or may not be apertured. The absorbent core 30 may also comprise a fibrous thermoplastic adhesive material that at least partially bonds each absorbent material layer to its respective material. These SAPs are also known as absorbent gelling materials or AGMs.

The absorbent core 30 may include one or more depressions. The one or more pits may be provided in addition to or instead of the one or more channels. The depressions may be areas of the absorbent core that are free or substantially free of absorbent material, such as SAP (including the ranges specified above). Other forms and more details regarding channels and pockets of no or substantially no absorbent material, such as SAP, within the absorbent core are discussed in greater detail in U.S. patent application publications 2014/0163500, 2014/0163506, and 2014/0163511, each published on 6/12 of 2014.

The configuration and construction of the absorbent core 30 may vary (e.g., the absorbent core 30 may have varying caliper zones, a hydrophilic gradient, a superabsorbent gradient, or lower average density and lower average basis weight acquisition zones). In addition, the size and absorbent capacity of the absorbent core 30 can also be varied to accommodate a wide variety of wearers. However, the total absorbent capacity of the absorbent core 30 should be compatible with the design loading and intended use of the sanitary napkin or any other disposable absorbent article.

In some forms of the invention, the absorbent core 30 may include a plurality of multi-functional layers in addition to the first and second absorbent layers. For example, the absorbent core 30 may include a core wrap (not shown) that may be used to enclose the first and second absorbent layers and other optional layers. The core wrap may be formed from two nonwoven materials, substrates, laminates, films, or other materials. The core wrap may comprise only a single material, substrate, laminate, or other material that is wrapped at least partially around itself.

The absorbent core 30 may comprise one or more adhesives, for example, to help immobilize any superabsorbent gelling material or other absorbent material that may be present in the core.

Absorbent cores containing relatively high levels of SAP with various core designs are disclosed in U.S. patent No. 5,599,335 to Goldman et al, EP 1,447,066 to Busam et al, WO 95/11652 to Tanzer et al, U.S. patent publication No. 2008/0312622a1 to huntorf et al, and WO 2012/052172 to Van Malderen. These designs can be used to construct the first and second superabsorbent layers. Alternative core embodiments are also described in U.S. Pat. Nos. 4,610,678 to Weisman et al, 9/1986; U.S. Pat. No.4,673,402 to Weisman et al, 6/16 1987; U.S. patent No.4,888,231 to Angstadt, 12/19/1989; and U.S. Pat. No.4,834,735 to Alemany et al, 5, 30, 1989. The absorbent core may further comprise additional layers which mimic a dual core system comprising an acquisition/distribution core of chemically rigid fibers positioned above the absorbent storage core, as described in U.S. patent No. 5,234,423 to alemny et al, 8/10, 1993; and U.S. Pat. No. 5,147,345.

The SAP of the present invention may have various compositions. A highly preferred type of hydrogel-forming absorbent gelling material is based on hydrolyzed polyacids, in particular neutralized polyacrylic acid. Hydrogel-forming polymeric materials of this type are those which, upon contact with fluids (i.e., liquids), such as water or body fluids, absorb such fluids and thereby form hydrogels. In this way, fluid discharged into the fluid absorbent structure herein may be collected and retained. These preferred superabsorbent polymers will generally comprise substantially water-insoluble, slightly crosslinked, partially neutralized, hydrogel-forming polymeric materials prepared from polymerizable, unsaturated, acid-containing monomers. In these materials, the polymer component formed from the unsaturated, acid-containing monomer may include the entire gelling agent, or may be grafted to other types of polymer moieties, such as starch or cellulose. Hydrolyzed polyacrylic acid grafted starch materials are the latter type. Thus, preferred superabsorbent polymers include hydrolyzed polyacrylonitrile-grafted starch, hydrolyzed polyacrylate-grafted starch, polyacrylates, maleic anhydride-isobutylene copolymers, and combinations thereof. Particularly preferred superabsorbent polymers are hydrolyzed polyacrylates and hydrolyzed polyacrylate grafted starch.

Regardless of the nature of the polymer component of the preferred superabsorbent polymers, such materials are generally lightly crosslinked. Crosslinking serves to render these preferred hydrogel-forming absorbent materials substantially water-insoluble, and crosslinking also determines, in part, the gel volume and extractable polymer characteristics of the hydrogels formed thereby. Suitable crosslinking agents are well known in the art and include, for example: (1) a compound having at least two polymerizable double bonds; (2) a compound having at least one polymerizable double bond and at least one functional group reactive with an acid-containing monomer material; (3) a compound having at least two functional groups reactive with the acid-containing monomeric material; and (4) polyvalent metal compounds capable of forming ionic crosslinks. Preferred crosslinkers are diesters or polyesters of unsaturated mono-or polycarboxylic acids with polyols, bisacrylamides and diallyl or triallylamines. Particularly preferred crosslinking agents are N, N' -methylenebisacrylamide, trimethylolpropane triacrylate and triallylamine. The crosslinking agent will generally comprise about 0.001 to 5 mole percent of the preferred species. More preferably, the cross-linking agent will comprise 0.01 to 3 mole percent of the absorbent gelling material used herein.

The superabsorbent polymers described above are typically used in the form of discrete particles. Such superabsorbent polymers can be of any desired shape, for example spherical or hemispherical, cubic, rod-like polyhedral, and the like. Shapes having a large ratio of largest dimension to smallest dimension, such as needles and flakes, are also contemplated for use herein. Agglomerates of fluid absorbent gelling material particles may also be used.

The size of the fluid-absorbent gelling material particles can vary within a wide range. For industrial hygiene reasons, an average particle size of less than about 30 microns is less desirable. Particles having a minimum dimension greater than about 2mm can also create a gritty feel in the absorbent article that is undesirable from a consumer aesthetic standpoint. In addition, the fluid absorption rate may be affected by particle size. Larger particles have a very reduced absorption rate. The fluid absorbent gelling material particles preferably have a particle size (substantially all particles) of about 30 microns to about 2 mm. As used herein, "particle size" refers to the weighted average of the smallest dimension of individual particles.

These layers are preferably substantially free of airfelt and therefore differ from the blend layer which may include airfelt. As used herein, "substantially free of airfelt" means less than 5%, 3%, 1%, or even 0.5% airfelt. In preferred cases, no measurable airfelt will be present in the superabsorbent layer of the absorbent core. As far as the first superabsorbent layer is concerned, it is preferably discontinuously disposed on the first distribution layer. As used herein, "discontinuous" or "in a discontinuous pattern" means that the superabsorbent polymer is applied to the first distribution layer in a pattern that separates the shaped regions. These regions of superabsorbent polymer or regions free of superabsorbent polymer can include, but are not limited to, linear stripes, non-linear stripes, circles, rectangles, triangles, waves, meshes, and combinations thereof. However, like the second superabsorbent layer, the first superabsorbent layer may be disposed in a continuous pattern on its respective distribution layer. As used herein, "continuous pattern" or "continuously" means that the material is deposited and/or secured to the superabsorbent carrier material and/or adjacent distribution layer in an uninterrupted manner such that the distribution layer is more fully covered by superabsorbent polymer.

The absorbent core may be a heterogeneous mass comprising the enrobeable elements and one or more portions of the foam pieces. The discrete portions of the foam bun are open-cell foam. The enrobeable elements may be webs such as nonwovens, fibrous structures, air-laid webs, wet-laid webs, high loft nonwovens, needle-punched webs, hydroentangled webs, tows, woven webs, knitted webs, flocked webs, spunbond webs, layered spunbond/meltblown webs, carded webs, coform webs of cellulosic fibers and meltblown fibers, coform webs of staple fibers and meltblown fibers, and layered webs that are layered combinations thereof. The foam may be a High Internal Phase Emulsion (HIPE) foam. Exemplary enrobeable elements and foams are described in detail below.

The open cell foam block may comprise between 1% to 99% by volume of a heterogeneous mass, such as, for example, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90% or 95% by volume of a heterogeneous mass.

The heterogeneous masses may have interstitial spaces that exist between the enrobeable elements, between the enrobeable elements and the enrobed elements, and between the enrobed elements. The void space may contain a gas, such as air. The void space may represent between 1% and 95% of the total volume of the fixed volume amount of heterogeneous mass, such as, for example, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90% of the total volume of the fixed volume amount of heterogeneous mass.

Forming devices for deforming a generally planar web into a three-dimensional structure are known for use in the present invention to modify an absorbent material as it is produced into an absorbent material having a relatively high permeability without a significant corresponding capillary pressure drop. The forming device may comprise a pair of intermeshing rolls, typically steel rolls having intermeshing ridges or teeth and grooves. However, it is contemplated that other means for achieving shaping may be utilized, such as the deforming roll and cord (cord) arrangement disclosed in US 2005/0140057 published on 30.6.2005. Accordingly, all disclosure herein of a pair of rolls is considered equivalent to a roll and a cord, and the claimed arrangement detailing two intermeshing rolls is considered equivalent to an intermeshing roll and a cord, wherein the cord serves as a ridge of a mating intermeshing roll. In one embodiment, the pair of intermeshing rolls of the invention can be considered equivalent to a roll and intermeshing elements, where the intermeshing elements can be another roll, a cord, a plurality of cords, a belt, a flexible web, or a belt. Likewise, other known forming techniques, such as creping, necking/consolidation, corrugating, embossing, snap-off (button break), hot-pin stamping, etc., are believed to produce absorbent materials having a degree of relatively high permeability without a corresponding reduction in capillary pressure. Forming methods using rolls include "ring rolling", "SELF", or "SELF' ing" processes, where SELF represents a structured elastic-like film (R) ((R))StructuralElasticLikeFilm), such as "microstructuresChemical-like elastic film "and" hob-holing "(RKA); as described in U.S. patent No. 7,935,207 to Zhao et al, 5/3/2011.

The distribution can be optimized according to the intended use of the heterogeneous mass. For example, a different distribution may be selected for absorption of aqueous fluids such as urine (for diapers) or water (for paper towels) than for absorption of proteinaceous fluids such as menses. Furthermore, the distribution can be optimized for the use, such as dosing the active substance or using the foam as a reinforcing element.

The absorbent core may also include similar optional layers. It may be a fibrous web, such as a layered web selected from the group consisting of fibrous structures, air-laid webs, wet-laid webs, high loft nonwovens, needle punched webs, hydroentangled webs, fiber tows, woven webs, knitted webs, flocked webs, spunbond webs, layered spunbond/meltblown webs, carded webs, coform webs of cellulosic fibers and meltblown fibers, coform webs of staple fibers and meltblown fibers, and layered webs that are layered combinations thereof.

These optional layers of core and chassis may include materials such as creped cellulose wadding, fluffed cellulose fibers, air-laid (airfelt), and woven fibers. The material of the optional layers may also be fibers, such as, for example, synthetic fibers, thermoplastic particles or fibers, tricomponent fibers, and bicomponent fibers, such as, for example, sheath/core fibers having the following polymer combinations: polyethylene/polypropylene, polyethylvinyl acetate/polypropylene, polyethylene/polyester, polypropylene/polyester, copolyester/polyester, and the like. An optional layer can be any combination of the above-listed materials and/or a plurality of the above-listed materials, alone or in combination.

The materials of the optional layers may be hydrophobic or hydrophilic depending on their location within the chassis.

The material of the optional layer may include constituent fibers comprising polymers such as polyethylene, polypropylene, polyester, and blends thereof. The fibers may be spunbond fibers. The fibers may be meltblown fibers. The fibers may comprise cellulose, rayon, cotton, or other natural materials or blends of polymers and natural materials. The fibers may also include superabsorbent materials such as polyacrylates or any combination of suitable materials. The fibers may be monocomponent, bicomponent and/or biconstituent, non-round (e.g., capillary channel fibers), and may have a major cross-sectional dimension (e.g., diameter of round fibers) in the range of 0.1 to 500 microns. The constituent fibers of the nonwoven precursor web can also be a mixture of different fiber types that differ in characteristics such as chemistry (e.g., polyethylene and polypropylene), composition (mono-and bi-), denier (micro-and >20 denier), shape (i.e., capillary and circular), and the like. The constituent fibers may range from about 0.1 denier to about 100 denier.

Optional layers may include thermoplastic particles or fibers. The material, particularly the thermoplastic fibers, can be made from a variety of thermoplastic polymers including polyolefins such as polyethylene (e.g., PULPEX)^TM) Polypropylene, polyester, copolyester, and copolymers of any of the foregoing.

Depending on the desired characteristics, suitable thermoplastic materials include hydrophobic fibers made hydrophilic, such as surfactant-treated or silica-treated thermoplastic fibers derived from, for example, polyolefins such as polyethylene or polypropylene, polyacrylates, polyamides, polystyrenes, and the like. The surface of the hydrophobic thermoplastic fibers can be treated with a surfactant, such as a nonionic or anionic surfactant, to become hydrophilic, for example, spraying the fibers with a surfactant, dipping the fibers into a surfactant, or including a surfactant as part of the polymer melt in the production of the thermoplastic fibers. Upon melting and resolidification, the surfactant will tend to remain at the surface of the thermoplastic fibers. Suitable surfactants include nonionic surfactants such as Brij 76 manufactured by ICI America, Inc. (Wilmington, Del.) and Pegosperse under the trademark^TMVarious surfactants are sold by Glyco Chemical, Inc. In addition to nonionic surfactants, anionic surfactants may also be used. These surfactants may be, for example, from about 0.2 to about 1g/cm²The amount of thermoplastic fiber is applied to the thermoplastic fiber。

Suitable thermoplastic fibers can be made from a single polymer (monocomponent fibers) or can be made from more than one polymer (e.g., bicomponent fibers). The polymer comprising the sheath often melts at a different (usually lower) temperature than the polymer comprising the core. Thus, these bicomponent fibers provide thermal bonding due to the melting of the sheath polymer while maintaining the desired strength characteristics of the core polymer.

Suitable bicomponent fibers for use in the present invention may include sheath/core fibers having the following polymer combinations: polyethylene/polypropylene, polyethylvinyl acetate/polypropylene, polyethylene/polyester, polypropylene/polyester, copolyester/polyester, and the like. Particularly suitable bicomponent thermoplastic fibers for use herein are those having a polypropylene or polyester core and a copolyester, polyethylvinyl acetate or polyethylene sheath having a lower melting temperature (e.g., DANAKLON)^TM、CELBOND^TMOr CHISSO^TMBicomponent fibers). These bicomponent fibers may be concentric or eccentric. As used herein, the terms "concentric" and "eccentric" refer to whether the sheath has a uniform or non-uniform thickness across the cross-sectional area of the bicomponent fiber. Eccentric bicomponent fibers are desirable when providing greater compressive strength at lower fiber thickness. Suitable bicomponent fibers for use herein can be uncrimped (i.e., unbent) or crimped (i.e., curved). Bicomponent fibers can be crimped by typical textile methods such as the stuffer box method or the gear crimping method to obtain a predominantly two-dimensional or "flat" crimp.

The optional layer may also include synthetic fibers that are not normally used as binder fibers but which modify the mechanical properties of the web. Synthetic fibers include cellulose acetate, polyvinyl fluoride, polyvinylidene 1, 1-dichloride, acrylics (such as orlon), polyvinyl acetate, insoluble polyvinyl alcohol, polyethylene, polypropylene, polyamides (such as nylon), polyesters, bicomponent fibers, tricomponent fibers, mixtures thereof, and the like. These may include, for example, polyester fibers such as polyethylene terephthalate (e.g., DACRON)^TMAnd KODEL^TM) High-melting-point crimped polyester fiber(e.g., KODEL manufactured by Eastman Chemical Co., Ltd.)^TM431) Hydrophilic nylon (HYDROFLIL)^TM) And so on. Suitable fibers may also hydrophilize hydrophobic fibers, such as surfactant-treated or silica-treated thermoplastic fibers derived from, for example, polyolefins such as polyethylene or polypropylene, polyacrylics, polyamides, polystyrenes, polyurethanes, and the like. In the case of non-binding thermoplastic fibers, their length may vary depending on the particular properties desired for the fibers. Typically, they are about 0.3cm to 7.5cm in length, such as about 0.9cm to about 1.5 cm. Suitable non-binding thermoplastic fibers can have a dtex in the range of from about 1.5 to about 35, such as from about 14 to about 20 dtex.

Optional Components

In various embodiments of the present invention, the disposable absorbent article of the present invention may comprise a pair of barrier cuffs extending along opposite edges of the body surface of the article topsheet. The cuffs extend along the longitudinal axis of the chassis in a parallel configuration to each other. The pair of barrier cuffs may also be attached to the backsheet rather than the topsheet, depending on the configuration of the product. Some examples of other suitable barrier cuffs are described in U.S. Pat. nos. 4,695,278; 4,704,115, respectively; 4,795,454; 4,909,803; U.S. patent application publication 2009/0312730.

In some forms, the first barrier cuff comprises a first cover and a first elastic member. The second barrier cuff includes a second cover and a second elastic member. The first cover may completely enclose the first elastic member. Similarly, the second cover may completely enclose the second elastic member.

In some forms of the invention where the product form is an incontinence pad or sanitary napkin, such product forms may include wings. The wings can provide additional leakage protection to the disposable absorbent article and can help secure its pad to the user's undergarment. Any suitable flap configuration known in the art may be used.

Adhesives may be used to bond all of the components together, including hot melt adhesives known in the art. The adhesive may be Findlay H2128 UN or Savare PM 17 and may be applied using the Dynafiber HTW system.

In the case of sanitary napkins or incontinence pads, such products can be held in place during use by any support or attachment suitable for such purpose. In some forms of the invention, the pad is placed over the user's undergarment or panty and secured thereto by a fastening adhesive. The fastening adhesive secures the pad in the crotch portion of the user's undergarment. A portion or the whole of the garment surface of the backsheet is coated with a fastening adhesive. Any adhesive or glue suitable for such purposes may be used as the fastening adhesive herein, for example using a pressure sensitive adhesive. Suitable binders include, for example, Century a-305-IV manufactured by Century adhesives corporation (columbu, Ohio); and Instant Lock 34-2823 manufactured by National Starch and chemical Company (Bridgewater, N.J.). Suitable adhesive fasteners are also described in U.S. Pat. No.4,917,697. Prior to use of the absorbent article, the pressure sensitive adhesive is typically covered by a removable release liner to prevent the adhesive from drying out or adhering to surfaces other than the crotch portion of the undergarment prior to use. Suitable release liners are also described in U.S. Pat. Nos. 4,917,697 and 4,556,146. Any commercially available release liner commonly used for such purposes may be utilized herein. Non-limiting examples of suitable release liners are BL30MG-A Silox E1/0 and BL30MG-A Silox 4P/O, both manufactured by Akrosil Corporation (Menasha, Wis.). The using method of the protective pad comprises the following steps: the release liner is removed and the absorbent article is then placed on the undergarment such that the adhesive contacts the undergarment. During use, the adhesive secures the absorbent article in place within the undergarment. The release liner may also be a wrap that is capable of individually wrapping the pad.

Furthermore, while much of the discussion herein is directed to sanitary napkins, it is contemplated that the present invention can also be used with taped diapers, pull-on training pants, adult incontinence diapers and pants, and replaceable pads for incontinence and menstrual fluid collection that can be inserted into and removed after use in disposable or durable panties or underwear.