Top sheet containing natural fibers

Abstract

To provide a topsheet comprising natural fibers for use in an absorbent article that has improved dryness characteristics while absorbing body fluids with no or little run-off.SOLUTION: A topsheet (24) for use in an absorbent article has at least a first layer (1). The first layer (1) comprises natural fibers of at least 15 wt.% based on the total weight of the first layer (1). The first layer (1) has a plurality of apertures (5). The first layer (1) comprises land areas (8) between most of the apertures (5). The contact angle on the land areas (8) of the first layer (1) between most of the apertures (5) is more than 70°, according to the Contact Angle Test Method. The topsheet (24) has a run-off of less than 40%, according to the Run-off Test Method.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention provides a topsheet having an outflow amount of less than 40% according to the outflow test method described herein. The topsheet can be used for personal hygiene articles such as disposable diapers for infants, training pants, sanitary napkins for women's hygiene, or adult incontinence products.

Background Art

[0002] Personal hygiene absorbent articles such as disposable diapers for infants, training pants for toddlers, adult incontinence underwear, and / or sanitary napkins are designed to absorb and contain excrement, particularly large amounts of urine, soft liquid feces (BM), and / or menstrual blood. These absorbent articles can include several layers that provide different functions, and, if desired, among the layers (e.g., capture layer, distribution layer, etc.), particularly, for example, a topsheet, a backsheet, and an absorbent core disposed between the topsheet and the backsheet.

[0003] The topsheet is generally liquid-permeable and is configured to receive fluids excreted from the body and help direct the fluids towards a capture system, a distribution system, and / or an absorbent core. One important characteristic of the topsheet is the ability to reduce the pooling of fluids on the topsheet before the absorbent article can absorb the fluids.

Summary of the Invention

Problems to be Solved by the Invention

[0004] There is still a need to provide a topsheet containing natural fibers for use in absorbent articles that have improved drying characteristics and absorb body fluids without allowing any or very little fluid to flow out.

Means for Solving the Problems

[0005] A top sheet for use in absorbent articles is disclosed, the top sheet having at least a first layer having a first surface and an opposing second surface. The first layer contains at least 15% by weight, or at least 30% by weight, or at least 50% by weight, or at least 60% by weight, or at least 75% by weight, or at least 95% by weight of natural fibers, relative to the total weight of the first layer. The first layer has a plurality of pores. The first layer includes land areas between most of the pores. The first surface land area contact angle on the land areas of the first surface of the first layer between most of the pores is greater than 70° according to a contact angle test method. The top sheet has a runoff of less than 40% according to a runoff test method. The top sheet may have a runoff of less than 20% according to a runoff test method.

[0006] Top sheets containing natural fibers tend to rapidly absorb bodily fluids and transport them through absorbent materials due to the hydrophilic properties of the natural fibers. However, bodily fluids tend to be retained within the top sheet by the natural fibers, resulting in the damp top sheet coming into contact with the wearer's skin. Therefore, the inventors have found that a balance between the hydrophobicity of the first layer and the hydrophilicity of the natural fibers due to the presence of pores within the first layer provides a top sheet that dries sufficiently and absorbs bodily fluids with little or no leakage. The above top sheet has low leakage and consequently reduces the risk of bodily fluid leakage.

[0007] Furthermore, the top sheet of the present invention, having a first layer with a claimed first surface land region contact angle on the land region between multiple pores on the first surface of the first layer, enables better absorption of bodily fluids. The top sheet can reduce contact of liquid excretions with the wearer's skin. Thus, the top sheet is sufficiently dry when in contact with the wearer's skin.

[0008] The natural fiber may be selected from the group consisting of cotton fiber, bamboo fiber, or mixtures thereof. Preferably, the natural fiber is cotton fiber.

[0009] Multiple pores can be uniformly distributed within the first layer.

[0010] In another respect, the contact angle over most of the pores may be 70° or less according to the contact angle test method. The top sheet may have a discharge and ingestion of less than 2 g / g at 30 cm water column according to the capillary discharge test method.

[0011] The width of most holes may be less than 1.5 mm, less than 1.2 mm, less than 1 mm, or less than 0.8 mm, according to the hole size test methods described below in this specification. The width of most holes may be 0.5 mm or less, according to the hole size test methods described below in this specification. Holes wider than 1.5 mm may result in increased red marking on the wearer's skin, increased re-wetting due to fluids returning into the top sheet from components beneath the top sheet (such as the absorbent core and / or fluid capture and distribution system), and bodily fluids passing through the top sheet. Larger holes may also cause discomfort to the consumer.

[0012] By treating the pores with a hydrophilic treatment, bodily fluids not absorbed by the hydrophobic first layer are rapidly transported through the pores towards the inner region of the absorbent material. If pores with a preferred width of less than 1.5 mm, less than 1.2 mm, less than 1 mm, or less than 0.8 mm are hydrophobic, this may adversely affect (rapid) liquid absorption within and through the pores. The liquid tension of generally hydrophilic bodily fluids such as urine can hinder proper absorption.

[0013] At least 20% of the pores of the first layer may be hydrophilic, preferably at least 30% of the pores of the first layer may be hydrophilic, and more preferably at least 50%, or at least 75%, or at least 90% of the pores of the first layer may be hydrophilic. Even more preferably, 100% of the pores may be hydrophilic.

[0014] The above top sheet provides improved fluid handling characteristics, such as reduced re-wetting of the absorbent material onto the surface facing the wearer, and better liquid capture.

[0015] The first layer may include a plurality of protrusions. The plurality of protrusions give the first layer a three-dimensional shape. Holes may be located between most of the protrusions, or between all of the protrusions.

[0016] Providing a three-dimensional first layer of the top sheet reduces skin / body fluid contact and / or skin / body fluid contact time during urination. Skin discomfort of the wearer of the absorbent article is reduced.

[0017] The top sheet may further have a second layer facing the first layer. The first and second layers may be in contact with each other between most of the protrusions, or between all of the protrusions. The second layer may have a number of holes that are at least partially or completely aligned with the holes of the first layer. The first layer may at least partially penetrate the second layer through the holes. The second layer may include land areas between most of the holes, or between all of the holes. The second layer may include synthetic fibers (e.g., thermoplastic fibers), natural fibers, and / or combinations thereof. The synthetic fibers may be single-component fibers, multi-component fibers, and combinations thereof. Alternatively, the second layer may not have holes.

[0018] The second layer does not have to have protrusions, and the contact angle of the second surface land region on the land region of the second layer between most or all of the holes may be 70° or less according to the contact angle test method.

[0019] Alternatively, though less desirable, the second layer may include a plurality of protrusions. The plurality of protrusions may impart a three-dimensional shape to the second layer. The plurality of holes in the first layer may be at least partially aligned with the plurality of holes in the second layer, or may be fully aligned. In this configuration, the contact angle between most or all of the holes and the land area of ​​the second surface of the second layer may be 70° or less, or greater than 70°, according to a contact angle test method.

[0020] In these configurations, the top sheet forms a three-dimensional laminate of two layers facing each other.

[0021] When the second layer is hydrophilic (i.e., the contact angle of the second surface land region is 70° or less), it improves the dewatering of the hydrophobic first layer that may come into contact with liquid excrement. Therefore, when a top sheet containing the two layers is incorporated into an absorbent article, this top sheet can reduce contact between the wearer's skin and liquid excrement.

[0022] Furthermore, when the second layer is hydrophobic (i.e., the contact angle of the second surface land region is greater than 70°), it reduces re-wetting of the absorbent article onto the surface facing the wearer.

[0023] Furthermore, the first surface land region post-conditioning contact angle on the land region of the first surface of the first layer after the conditioning process may be greater than 50° according to the post-conditioning contact angle test method described below herein. The conditioning process simulates usage conditions in which the top sheet and the absorbent article as a whole can be subjected to relatively high levels of liquid filling in a very short time during urination. Therefore, having a first surface land region post-conditioning contact angle greater than 50° on the land region of the first surface of the first layer after the conditioning process reflects the fact that improved top sheet drying performance can be achieved even under usage conditions involving high levels of bodily fluid filling in a short time within the frame.

[0024] The present invention also relates to an absorbent article comprising a longitudinal centerline, a transverse centerline perpendicular to the longitudinal centerline, a top sheet as described herein, an absorbent core, and a back sheet. The absorbent core is at least partially located between the top sheet and the back sheet.

[0025] The present invention also relates to a top sheet for use in absorbent articles, having at least a first layer. The first layer contains at least 80% by weight of natural fibers relative to the total weight of the first layer. The first layer comprises 5% to 40% by weight of hydrophilic fibers selected from the group consisting of synthetic fibers, natural fibers, and / or combinations thereof, and 60% to 95% by weight of hydrophobic natural fibers relative to the total weight of the first layer. The top sheet has a runoff of less than 40% according to a runoff test method. [Brief explanation of the drawing]

[0026] The above and other features and advantages of this disclosure, as well as the ways in which they are realized, will become clearer and the disclosure itself will be better understood by referring to the following descriptions of embodiments of this disclosure in conjunction with the accompanying drawings. [Figure 1a] This is a schematic diagram of a top sheet having a flat first layer according to the present invention. [Figure 1b] This is another schematic diagram of a top sheet having a flat first layer according to the present invention. [Figure 2] This is a schematic diagram of a top sheet having a three-dimensional first layer according to the present invention. [Figure 3] This is another schematic diagram of a top sheet having a three-dimensional first layer according to the present invention. [Figure 4a] This is a schematic diagram of a top sheet having a first layer and a second layer according to the present invention. [Figure 4b] This is a schematic diagram of a top sheet having a first layer and a second layer according to the present invention. [Figure 5] This is a schematic diagram of a top sheet having a three-dimensional first layer and a flat second layer according to the present invention. [Figure 6] This is a schematic diagram of a three-dimensional top sheet having a first layer and a flat second layer according to the present invention. [Figure 7] This is a schematic example of a first exemplary process for forming the top sheet of the present disclosure. [Figure 8]This diagram shows the interlocking engagement of a portion of the first roll and the second roll according to the present disclosure. [Figure 9] This is a diagram of a portion of the first roll as disclosed herein. [Figure 10] This is a diagram of a portion of the second roll as disclosed in this disclosure. [Figure 11] This is a schematic example of a second exemplary process for forming the top sheet of the present disclosure. [Figure 12] This is a top view of an exemplary absorbent article in the form of a diaper, which may include a top sheet of the present invention, with several layers partially removed. [Figure 13] Figure 12 is a cross-sectional view of a diaper. [Figure 14] This is a top view of an exemplary absorbent article in the form of a diaper, which may include a top sheet of the present invention having a region substantially free of absorbent material. [Figure 15] Figure 14 is a cross-sectional view of the item. [Figure 16] This is a cross-sectional view of an article cut at the same point as in Figure 15, where a channel is formed in the core as a result of the diaper being filled with fluid. [Figure 17] This is a micrograph illustrating an exemplary water droplet on a fiber for the contact angle testing method disclosed herein. [Modes for carrying out the invention]

[0027] Definition of Terms As used in the present invention, the term “absorbent article” refers to a disposable product, such as a diaper, pants, or sanitary napkin, that is positioned in direct contact with or in close proximity to the wearer’s body to absorb and contain various liquid excrements excreted from the body. Typically, these absorbent articles include a top sheet, a back sheet, and an absorbent core, and optionally a trapping layer and / or a distribution layer and other components, the absorbent core usually positioned between the back sheet and the trapping system or top sheet. The absorbent article of the present invention may be a diaper or pants.

[0028] As used herein, the term “diaper” refers to an absorbent article intended to be worn by a wearer around the lower torso to absorb and contain liquid excretion from the body. Diapers may be worn by children (e.g., infants or toddlers) or adults. Diapers may be provided with fastening members.

[0029] As used herein, the term “pants” refers to an absorbent article having fixed edges, a waist opening, and leg openings, designed for a child or adult wearer. The pants are positioned appropriately on the wearer by inserting the wearer’s legs into a pair of leg openings and sliding the pants-type absorbent article around the lower part of the wearer’s torso. The pants may be pre-formed by any preferred method, including, but not limited to, reattachable and / or non-reattachable fasteners (e.g., sutures, welds, adhesives, tacks, etc.) to join parts of the absorbent article together. The pants may be pre-formed at any position along the outer circumference of the article (e.g., side fastening, front waist fastening).

[0030] The degree of hydrophilicity or hydrophobicity can be measured in each case by determining the contact angle of water with the specific material.

[0031] The term "hydrophilic" refers to a material having a contact angle of 70° or less (i.e., the first surface land area contact angle, the second surface land area contact angle, the pore contact angle, the first surface land area after conditioning contact angle, or the second surface land area after conditioning contact angle) according to the contact angle test methods described herein.

[0032] The term "hydrophobic" refers to a material having a contact angle greater than 70° (i.e., the first surface land region contact angle, the second surface land region contact angle, the pore contact angle, the first surface land region after conditioning, or the second surface land region after conditioning) according to the contact angle test methods described herein.

[0033] As used herein, the term “mostly pores” means more than 50%, or more than 60%, or more than 70%, or more than 80%, or more than 90% up to 100% of the pores in the top sheet.

[0034] As used herein, the term “most of the protrusions” means more than 50%, or more than 60%, or more than 70%, or more than 80%, or more than 90% up to 100% of the protrusions within the top sheet.

[0035] The term "bonding region" means a region in which the first and second layers of the top sheet of the present invention are joined together or attached to each other by some method of bonding for forming the top sheet.

[0036] As used herein, the term “nonwoven web” refers to a material manufactured by bonding webs, sheets, or butts of aligned or randomly oriented fibers by friction and / or adhesive and / or bonding, and does not include paper, or manufactured products such as woven fabrics, knitted fabrics, tufts, stitch bonds, or wet-fulling felts, with or without further needlework, containing tangled or filament yarns. The fibers may be of natural or artificial origin. The fibers may be staples or continuous filaments, or formed in situ. The porous fiber structure of the nonwoven may be configured to be permeable or impermeable to liquids, as desired.

[0037] The term “spunlace nonwoven fabric” refers to a nonwoven fabric in which the binding and entanglement of fibers are not by mechanical means, but by multiple water jets under pressure passing through a moving fleece or fabric, such as needles, causing the fibers to interweave with each other. These spunlace nonwoven fabrics are defined in essence by the fact that their compaction results from hydrostatic confluence. As used herein, “spunlace nonwoven fabric” also refers to a nonwoven fabric formed from two webs, which are combined with each other by hydrostatic confluence. The two webs may undergo a bonding process, such as thermal and / or pressure bonding, by imparting a bonding pattern using, for example, patterned calender rolls and anvil rolls, before being combined into a single nonwoven fabric by hydrostatic confluence. However, the two webs are combined with each other solely by hydrostatic confluence.

[0038] Typically, as used herein, the term “cellulose fiber” refers to natural fibers that are wood pulp fibers. Applicable wood pulps include chemical pulps such as kraft pulp, sulfite pulp, and sulfate pulp, as well as mechanical pulps such as wood pulp, thermomechanical pulp, and chemically modified thermomechanical pulp. Pulps derived from both deciduous trees (hereinafter also referred to as “hardwood”) and coniferous trees (hereinafter also referred to as “softwood”) can be used. Hardwood fibers and softwood fibers can be compounded or deposited in layers to provide a layered web.

[0039] The terms “comprise,” “comprising,” and “comprises” are non-exclusive terms that, each, identify the presence of a feature (e.g., a component) described thereafter, but do not exclude the presence of other features (e.g., elements, processes, or components known in the art or disclosed herein). These terms based on the verb “comprise” should be interpreted as encompassing the narrower terms “consisting essential of” and “consisting of,” which exclude unspecified elements, processes, or components that substantially affect the manner in which the feature functions. None of the preferred or exemplary embodiments described below limit the scope of the claims unless specifically indicated. Similarly, terms such as “typically,” “usually,” and “favorably” modify features that are not intended to limit the scope of the claims unless specifically indicated.

[0040] Top sheet containing natural fibers: The top sheet is generally permeable to liquids and is configured to receive fluids excreted from the body and to help direct the fluid towards the capture system, distribution system, and / or absorbent core. One of the key properties of the top sheet is its ability to reduce the accumulation of fluid on the top sheet before it can be absorbed by the absorbent material.

[0041] Generally, the top sheet can be made hydrophilic by a surfactant treatment, and body fluids are attracted to the top sheet before flowing into the underlying capture system, distribution system, and / or absorbent core.

[0042] The top sheet of the present invention contains natural fibers such as cotton or bamboo fibers, which are natural cellulose fibers known to be flexible, biodegradable, and less likely to cause allergies, irritation, or rashes. Natural fibers are highly hydrophilic. Therefore, top sheets containing natural fibers are typically highly hydrophilic. However, in this case, bodily fluids remain on and within the top sheet for extended periods, resulting in a damp feeling and skin discomfort for the user.

[0043] To address issues such as a damp feel during urination due to prolonged fluid retention on the top sheet, top sheets containing natural fibers may be treated with a hydrophobic coating. In such cases, perforated top sheets have been used to allow for faster penetration of bodily fluids. While perforated top sheets generally reduce fluid sagging on the top sheet, perforated top sheets can still have relatively high runoff, for example, due to relatively small pores through which liquid penetrates slowly or not at all.

[0044] Hydrophobic coatings must be resistant to washing through multiple leaks to ensure a dry feel throughout the entire wear cycle. Washing of the hydrophobic coating material into the absorbent article components beneath the top sheet can also adversely affect the fluid handling and storage properties of the article.

[0045] Because relatively large holes increase red marking on the wearer's skin and increase re-wetting due to bodily fluids returning from components beneath the top sheet into the top sheet and passing through the top sheet, the size of individual holes should preferably be relatively small without increasing the outflow caused by smaller holes.

[0046] Furthermore, the three-dimensional shape of the top sheet can further help reduce the amount of top sheet leakage, improving comfort and aesthetics.

[0047] The top sheet of the present invention is part of an absorbent article that comes into contact with the wearer's skin during use. As is known to those skilled in the art, the top sheet can be bonded to a portion of the back sheet, an absorbent core, a barrier leg cuff of the absorbent article, and / or any other layer. Furthermore, at least a portion or all of the top sheet can be made liquid permeable, thereby allowing liquid bodily waste to easily penetrate through its thickness.

[0048] The top sheet of the present invention contains natural fibers and may further contain synthetic fibers.

[0049] Synthetic fibers may be selected from the group consisting of polyester, polypropylene, polyethylene, polyether, polyamide, polyhydroxyalkanoate, polysaccharide, and combinations thereof. More specifically, synthetic fibers may be selected from the group consisting of polyethylene terephthalate, polybutylene terephthalate, poly(1,4-cyclohexylenedimethylene terephthalate), isophthalic acid copolymer (e.g., terephthalate-cyclohexylene-dimethylene isophthalate copolymer), ethylene glycol copolymer (e.g., ethylene terephthalate-cyclohexylene-dimethylene copolymer), polycaprolactone, polyhydroxyl ether ester, polyhydroxyl etheramide, polyesteramide, polylactic acid, polyhydroxybutyrate, and combinations thereof. In addition, other synthetic fibers such as rayon, polyethylene, and polypropylene fibers may be used within the scope of this disclosure.

[0050] Preferably, the synthetic fiber is selected from the group consisting of polypropylene, polyethylene, polyester, polyethylene terephthalate, polybutylene terephthalate, polyamide, polylactic acid, and combinations thereof.

[0051] Furthermore, synthetic fibers may be single-component fibers (i.e., a single synthetic material or mixture constitutes the entire fiber), multi-component fibers such as two-component fibers (i.e., the fiber is divided into regions, and each region contains two or more different synthetic materials or mixtures thereof), or combinations thereof.

[0052] A non-limiting example of a suitable two-component fiber is a fiber made from a copolymer of polyester (polyethylene terephthalate / isophthalate / polyester (polyethylene terephthalate)), which is known as the "CoPET / PET" fiber commercially available from Fiber Innovation Technology, Inc. (Johnson City, TN).

[0053] The top sheet may also contain semi-synthetic fibers made from polymers, specifically hydroxyl polymers. Suitable hydroxyl polymers, non-limiting examples, include polyvinyl alcohol, starch, starch derivatives, chitosan, chitosan derivatives, cellulose derivatives such as viscose, rubber, arabinan, galactan, lyocell (Tencel®), and combinations thereof.

[0054] Natural fibers may be selected from the group consisting of wheat straw fibers, rice straw fibers, flax fibers, bamboo fibers, cotton fibers, jute fibers, hemp fibers, sisal fibers, bagasse fibers, hesper aloe fibers, reeds, seawater or freshwater algae / seaweed, and combinations thereof.

[0055] Preferably, the natural fiber is selected from the group consisting of cotton fiber, bamboo fiber, or a mixture thereof. Preferably, the natural fiber is cotton fiber.

[0056] Some examples of nonwoven materials suitable for use as a top sheet include, but are not limited to, spunbonded nonwovens, carded nonwovens, carded air-through nonwovens, spunlace nonwovens, needle-punched nonwovens, and nonwovens having relatively special properties that allow them to be easily deformed.

[0057] The nonwoven web can be formed by many processes such as, for example, the airlaid process, the wet process, the meltblown process, the spunbond process, the needle punch process, and the carding process. The fibers in the nonwoven web can then be bonded via the spunlace process, hydroentanglement, calendar bonding, through-air bonding, and resin bonding.

[0058] One suitable nonwoven material as the topsheet can be a stretch polypropylene / polyethylene spunbond nonwoven. One suitable nonwoven material as the topsheet can be a spunbond nonwoven containing polypropylene and polyethylene. The fibers may include a blend of polypropylene and polyethylene. Alternatively, the fibers may include composite fibers such as core-sheath fibers where the sheath of the fiber is polyethylene and the core of the fiber is polypropylene.

[0059] The topsheet may be a spunlace nonwoven.

[0060] The topsheet is about 8 to about 60 g / m 2 Preferably about 10 to about 50 g / m 2 More preferably about 12 to about 40 g / m 2 and may have a basis weight.

[0061] The first layer is 8 g / m 2 to 60 g / m 2 or 12 g / m 2 to 5 o g / m 2 or 15 g / m 2 to 40 g / m 2 and may have a basis weight. The optional second layer is 5 g / m 2 to 50 g / m 2 or 7 g / m 2 to 40 g / m 2 or 8 g / m 2 to 35 g / m 2 and may have a basis weight.

[0062] The topsheet of the present invention has at least a first layer. Preferably, the first layer of the topsheet is in direct contact with the skin of the wearer.

[0063] The top sheet may be formed of a single layer, two layers, or, less preferably, more than two layers.

[0064] Layer 1: The first layer may contain natural fibers and may be a woven or nonwoven web. The first layer may further contain synthetic fibers.

[0065] The lists of synthetic and natural fibers correspond to the lists disclosed above for the top sheet.

[0066] Nonwoven webs can be formed by many processes, such as air-laying, wet processes, melt-blown processes, spunbonding processes, needle-punching processes, and carding processes. The fibers in the nonwoven web can then be bonded through spunlacing, water-flow entanglement, calendering, through-air bonding, and resin bonding.

[0067] Preferably, the first layer of the top sheet is a spunlace nonwoven fabric.

[0068] Preferably, the synthetic fiber is selected from the group consisting of polypropylene, polyethylene, polyester, polyethylene terephthalate, polybutylene terephthalate, polyamide, polylactic acid, and combinations thereof.

[0069] Synthetic fibers can be single-component fibers, multi-component fibers such as two-component fibers, or combinations thereof.

[0070] Preferably, the natural fiber is selected from the group consisting of cotton fiber, bamboo fiber, or a mixture thereof. Preferably, the natural fiber is cotton fiber.

[0071] Cotton fibers are natural cellulose fibers that possess good liquid capture, good breathability, and good flexibility. Therefore, having a top sheet containing a first layer of cotton fibers improves the flexibility of the top sheet while improving its fluid handling properties.

[0072] The fibers may have any suitable denier or denier range, and / or fiber length or fiber length range.

[0073] The first layer contains natural fibers such as cotton fibers in an amount of at least 15% by weight, or at least 30% by weight, or at least 50% by weight, or at least 60% by weight, or at least 75% by weight, or at least 95% by weight, relative to the total weight of the first layer. The first layer may also be made of natural fibers such as cotton fibers in an amount of 99% to 100% by weight, relative to the total weight of the first layer.

[0074] Since the first layer of the top sheet may come into direct contact with the wearer's skin during use of the absorbent article, having a high content of natural fibers such as cotton fibers in the first layer of the top sheet allows for a soft feel against the wearer's skin and increases the amount of biodegradable material in contact with the wearer's skin, thereby reducing the risk of allergies, irritation, or rashes on the wearer's skin.

[0075] The first layer has multiple holes. The first layer includes land regions between most of the holes.

[0076] The contact angle between the land regions of the first surface of the first layer, between most of the pores, is greater than 70° according to the contact angle test method. The first layer is hydrophobic.

[0077] Preferably, the first surface land region contact angle on the land region of the first surface of the first layer between most of the holes is greater than 80° according to the contact angle test method. More preferably, the first surface land region contact angle on the land region of the first surface of the first layer between most of the holes is greater than 90° according to the contact angle test method. Even more preferably, the first surface land region contact angle on the land region of the first surface of the first layer between most of the holes is greater than 95° and up to 130° according to the contact angle test method.

[0078] A hydrophobic treatment may be applied to the first layer. The hydrophobic treatment may be petrochemical or, at least to some extent, derived from natural resources. The hydrophobic treatment may be a petroleum wax or wax emulsion. The hydrophobic treatment may be naturally derived. The hydrophobic treatment may be selected from the group consisting of natural oils, butters or waxes, and combinations thereof. Some examples, but not limited to, are cottonseed oil, coconut oil, avocado oil, jojoba oil, castor oil, soybean oil, almond oil, lanolin oil, olive oil, sunflower seed oil, eucalyptus oil, shea butter, cocoa butter, murumuru butter, almond butter, aloe butter, mango butter, beeswax, soybean wax, candelilla wax, rice bran wax, and coconut wax.

[0079] The amount of hydrophobic treatment used may increase as the proportion of cotton fibers present in the first layer increases. The range of hydrophobic treatment is 0.1 g / m 2 ~Up to 10g / m 2 Preferably 0.5 g / m 2 ~4g / m 2 It could be that basis weight.

[0080] The hydrophobic treatment may be performed using a hydrophobic surfactant such as a silicone polymer or polyether.

[0081] Preferably, the first layer includes a hydrophobic treatment.

[0082] At least 60% of the total volume of the first layer of the top sheet may include a hydrophobic treatment. Preferably, at least 70% of the total volume of the first layer of the top sheet includes a hydrophobic treatment.

[0083] The first surface land region post-conditioning contact angle on the land region of the first surface of the first layer after the conditioning process may be greater than 50° according to the post-conditioning contact angle test method. Preferably, the first surface land region post-conditioning contact angle on the land region of the first surface of the first layer after the conditioning process may be greater than 60° according to the post-conditioning contact angle test method described below herein.

[0084] Hydrophobic treatment can be applied via kissroll coating, spraying, gravure printing, slot coating, dipping, or other application processes known in the art.

[0085] The hydrophobic treatment may be applied in this manner, or it may be first dissolved in a solvent and then removed after application, or it may be first mixed with water to form an emulsion and then removed after application. When the hydrophobic treatment is first mixed with water to form an emulsion, an emulsifier may be required.

[0086] Alternatively, the first layer may contain a mixture of hydrophobic natural fibers and hydrophilic natural fibers. The hydrophobic natural fibers may be hydrophilic natural fibers that have been treated with a hydrophobic treatment before forming the first layer.

[0087] The amount of hydrophobic natural fibers may be greater than the amount of hydrophilic natural fibers.

[0088] For example, the first layer may contain a mixture of hydrophilic natural fibers in an amount of 5% to 40% by weight and hydrophobic natural fibers in an amount of 60% to 95% by weight, relative to the total weight of the first layer.

[0089] Alternatively, the first layer may include a mixture of hydrophilic fibers selected from the group consisting of synthetic fibers, natural fibers, and / or combinations thereof, and hydrophobic natural fibers. The hydrophobic natural fibers may be hydrophilic natural fibers that have been treated with a hydrophobic treatment before forming the first layer.

[0090] The amount of hydrophobic natural fibers may be greater than the amount of hydrophilic fibers.

[0091] For example, the first layer may contain a mixture of hydrophilic fibers in an amount of 5% to 40% by weight and hydrophobic natural fibers in an amount of 60% to 95% by weight, relative to the total weight of the first layer.

[0092] Alternatively, natural hydrophobic fibers such as cotton fibers that are not treated by washing and / or decolorization with hydrophobic treatment may be used. Alternatively, hydrophobic viscose fibers may be used as is known in the art.

[0093] Alternatively, the first layer may be a spunlace nonwoven fabric layer comprising a carrier web and a web containing natural fibers, the latter of which contains natural fibers in part that enter the carrier web. The carrier web may be a nonwoven fabric web.

[0094] A web containing natural fibers may be formed on one side of the carrier web. The natural fibers of the natural fiber web may enter the fiber network of the carrier web and become entangled with the fiber network. Naturally, the natural fibers may become entangled with each other. The carrier web may also become entangled with the web containing natural fibers.

[0095] The carrier web may be made from different types of synthetic fibers. The carrier web may also be made from cellulose fibers.

[0096] Synthetic fibers may be selected from the group consisting of polyester, polypropylene, polyethylene, polyether, polyamide, polyhydroxyalkanoate, polysaccharide, and combinations thereof. More specifically, synthetic fibers may be selected from the group consisting of polyethylene terephthalate, polybutylene terephthalate, poly(1,4-cyclohexylenedimethylene terephthalate), isophthalic acid copolymer (e.g., terephthalate-cyclohexylene-dimethylene isophthalate copolymer), ethylene glycol copolymer (e.g., ethylene terephthalate-cyclohexylene-dimethylene copolymer), polycaprolactone, polyhydroxyl ether ester, polyhydroxyl etheramide, polyesteramide, polylactic acid, polyhydroxybutyrate, and combinations thereof. In addition, other synthetic fibers such as rayon, polyethylene, and polypropylene fibers may be used within the scope of this disclosure.

[0097] Preferably, the synthetic fiber is selected from the group consisting of polypropylene, polyethylene, polyester, polyethylene terephthalate, polybutylene terephthalate, polyamide, polylactic acid, and combinations thereof.

[0098] The carrier web may contain spunbond fibers or carded fibers. The carrier web may be a carded web or a spunbond web.

[0099] A web containing natural fibers may include natural fibers selected from the group consisting of cotton fibers, bamboo fibers, and mixtures thereof. Preferably, a web containing natural fibers includes cotton fibers.

[0100] A web containing natural fibers may also contain staple fibers. Natural fibers may also contain staple fibers.

[0101] A web containing natural fibers may contain at least 70% by weight, or at least 80% by weight, of cotton fibers, based on the total weight of the web, and may contain 0% to 20% by weight, or 1% to 10% by weight, or 1% to 5% by weight, of other fibers such as rayon fibers, pulp fibers, synthetic fibers (such as heat-meltable fibers), or combinations thereof, based on the total weight of the web.

[0102] The capillary force can gradually increase from the sides of the first layer when the web containing natural fibers is formed in the center of the first layer in the thickness direction. Thus, the first layer of the top sheet exhibits improved liquid handling properties from the web containing natural fibers towards the inside of the first layer, thereby providing a dry feel on the sides where the web containing natural fibers is formed.

[0103] Furthermore, because a portion of the web containing natural fibers enters the carrier web, the web containing natural fibers has enhanced mechanical strength, such as tensile strength, and therefore improves the mechanical strength of the top sheet.

[0104] The first layer may be a nonwoven fabric layer comprising at least 20% by weight of natural fibers relative to the total weight of the first layer, and 80% by weight or less of synthetic fibers such as thermoplastic fibers relative to the total weight of the first layer. Preferably, the first layer comprises at least 30% by weight of natural fibers relative to the total weight of the first layer, and 70% by weight or less of synthetic fibers such as thermoplastic fibers relative to the total weight of the first layer.

[0105] A preferred process for generating the first layer as described above is then described, corresponding to a water flow entanglement process. The carrier web may be formed by a through-air bonding process, an air-laying process, a carding process, or other known processes in the art for forming a nonwoven web. For example, by using a through-air bonding process, a mixture of synthetic fibers may be formed within the carrier web using a carding machine, and hot air at a predetermined temperature may be blown through the carrier web to fuse the fiber entanglements. The carrier web may be conveyed on a wire mesh endless belt.

[0106] Separately, webs containing natural fibers can be obtained, for example, by a card processing machine.

[0107] The resulting web containing natural fibers may be superimposed on a moving carrier web, and a water jet from a jet nozzle may be directed onto the web containing natural fibers. When the water jet hits the web, entanglement may occur within the web containing natural fibers between the natural fibers and the constituent fibers of the carrier web, thus forming a spunlace nonwoven fabric. The water jet may also be directed onto the carrier web, or onto both webs.

[0108] The top sheet of the present invention has at least a first layer. The first layer may contain natural fibers at least 80% by weight of the total weight of the first layer, or at least 85% by weight of natural fibers, or at least 90% by weight of natural fibers, or further, at least 95% by weight of natural fibers up to 100% by weight of natural fibers.

[0109] Preferably, the natural fiber is selected from the group consisting of cotton fibers and bamboo fibers. Preferably, the natural fiber is cotton fiber.

[0110] The first layer comprises 5% to 40% by weight of hydrophilic fibers selected from the group consisting of synthetic fibers, natural fibers, and / or combinations thereof, and 60% to 95% by weight of hydrophobic natural fibers relative to the total weight of the first layer.

[0111] Hydrophobic natural fibers may also be hydrophilic natural fibers that have been treated with a hydrophobic process.

[0112] The top sheet described above has a leakage rate of less than 40% according to the leakage test method. This top sheet, when fully dried, absorbs bodily fluids with little to no leakage. The top sheet has a low leakage rate, which consequently reduces the risk of bodily fluid leakage.

[0113] Structure of the first layer: Referring to Figure 1a, the top sheet 24 includes at least the first layer 1.

[0114] The first layer 1 may have a first surface 3 and a second surface 4. When the top sheet described herein is incorporated into an absorbent article, the first surface 3 of the first layer 1 faces the wearer's body during use of the article, and the second surface 4 of the first layer 1 faces the back sheet.

[0115] The first layer 1 has multiple pores 5. The pores in the first layer of the top sheet play a crucial role in enabling initial and rapid fluid flow, despite the hydrophobic nature of the first layer. Thus, the hydrophobic first layer of the top sheet works in conjunction with the pores to reduce wetting on the surface of the top sheet facing the wearer.

[0116] Multiple pores 5 can be uniformly distributed within the first layer 1. To ensure material stability, regardless of their specific shape and width, the minimum distance between most of the pores is preferably at least 0.5 mm, more preferably at least 1.5 mm. This distance is measured on the first surface 3 of the first layer 1 of the top sheet.

[0117] The first layer includes land regions 8 between most of the holes 5. The land regions 8 may be substantially flat regions. Preferably, the land regions 8 are flat regions.

[0118] The land region 8 may completely enclose the hole 5. The land region may together form a substantially continuous grid across the entire plane of the first layer, while the hole 5 may be a separate element dispersed within and surrounded by the continuous grid.

[0119] The shape of the holes may vary. For example, the shape of the holes as viewed from the first surface of the first layer may be circular, elliptical, rectangular, or polygonal. Preferably, the holes have a circular, elliptical, or polygonal shape.

[0120] The three-dimensional shape of the hole may be cylindrical (for example, having a circular or elliptical base), prism (for example, having a polygonal base), or truncated cone or pyramid.

[0121] The hole 5 may be a simple opening without side walls, as shown in Figure 1b.

[0122] Alternatively, the majority of the holes 5 of the present invention may include side walls that extend outward away from the land region 8 of the second surface of the first layer, as shown in Figure 1a.

[0123] When the top sheet described herein is incorporated into an absorbent article, the orientation of the side walls of the holes may be toward the absorbent core of the absorbent article, or, less preferably, toward the wearer's skin during use of the article.

[0124] The extent of the sidewalls of the holes should be at least 0.1 mm beyond the first surface of the first layer, preferably at least 0.2 mm beyond the first surface of the first layer. The sidewalls of the holes may form a funnel or a channel.

[0125] The multiple holes 5 may include side walls having a top portion 6 proximal to the first surface 3 of the first layer and a bottom portion 7 proximal to the second surface 4 of the first layer.

[0126] Alternatively, as shown in Figure 1b, the multiple holes 5 may have a top portion 6 proximal to the first surface 3 of the first layer and a bottom portion 7 proximal to the second surface 4 of the first layer.

[0127] The term "pore apex" refers to the portion of a pore that is proximal to the first surface of the first layer.

[0128] The term "bottom of the pore" refers to a portion of the pore that is proximal to the second surface of the first layer, or proximal to the bottom edge of the pore.

[0129] The hole may be tapered, or it may be conical in shape such that the diameter of the hole is greater at the top of the hole and proximal to the second surface than at the diameter of the opening at the bottom edge of the hole.

[0130] Such a tapered structure helps reduce the risk of rewetting, i.e., the risk of body fluids returning to the top sheet (such as the absorbent core) from the components below the top sheet and passing through the top sheet. In the case of a perforated hydrophobic top sheet, rewetting occurs mainly through the pores. The tapered shape of the pores can help reduce rewetting because the diameter of the pores toward the absorbent core is smaller than the diameter of the pores in the first layer.

[0131] The width of the multiple holes may also vary.

[0132] On one side, the contact angle between the first surface land region on the first surface of the first layer between most of the holes is greater than 70° according to the contact angle test method.

[0133] The contact angle of the second surface land region on the second surface of the first layer between most of the holes can be greater than 70° according to the contact angle test method.

[0134] The total opening area of ​​most of the holes may be within the range of 5% to 50% of the surface area of ​​the first layer.

[0135] These wide pores are provided to facilitate the transport of bodily fluids of varying viscosities, particularly fecal matter, from the surface facing the wearer towards the absorbent structure. These wide pores compensate for the hydrophobic properties of the first layer of the top sheet, which has low absorbency.

[0136] The contact angle of the first surface land region on the first surface of the first layer between most of the holes may be greater than 70° according to the contact angle test method. The contact angle of the second surface land region on the second surface of the first layer between most of the holes may be greater than 70° according to the contact angle test method.

[0137] The hole contact angle over most of the hole may be 70° or less according to the contact angle test method. Specifically, the hole contact angle over most of the top and bottom of the hole may be 70° or less according to the contact angle test method.

[0138] The contact angle of the first surface land region on the first surface of the first layer between most of the holes may differ from the hole contact angle on most of the holes in the first layer by at least 10°, or at least 15°.

[0139] Hydrophilic treatment can be applied to most of the pores. The hydrophilic treatment may be a hydrophilic polymer. The hydrophilic treatment may be a hydrophilic surfactant such as BASF's Pluronic® surfactant, BASF's Tetronic® surfactant, or a combination thereof.

[0140] Most of the pores may contain hydrophilic surfactants.

[0141] Hydrophilic treatment can be applied to most of the holes via a perforating pin process, a printing process, or via a hydrophilic hot-melt adhesive between at least two layers of the top sheet.

[0142] For example, the perforation pin process may correspond to a process having three rolls, where the first roll extracts a hydrophilic surfactant from the bath and transfers it to an intermediate roll that wets the needles of the perforation roll. Such perforation roll needles can create holes in the nonwoven fabric layer while wetting the side walls of the holes. Excess hydrophilic surfactant can be removed with a vacuum roller.

[0143] The pores in the first layer of the top sheet may have a hydrophilic opening area of ​​at least 4%, preferably at least 6%, and more preferably at least 8%.

[0144] At least 20% of the pores in the first layer may be hydrophilic, preferably at least 30% of the pores in the first layer may be hydrophilic, and more preferably at least 50%, or at least 75%, or at least 90% of the pores in the first layer may be hydrophilic. Even more preferably, 100% of the pores may be hydrophilic. The amount of hydrophilic polymer applied to the pores is 0.01 to 10 g / m², based on the first total surface area of ​​the first layer (projected area, i.e., area considering the three-dimensional surface configuration). 2 It could be within the range.

[0145] When the majority of the pores are hydrophilic, the width of the majority of the pores may be less than 1.5 mm, less than 1.2 mm, less than 1 mm, or less than 0.8 mm, according to the pore size test method. The width of the majority of the pores may be 0.5 mm or less, according to the pore size test method described below in this specification.

[0146] By treating the pores with a hydrophilic coating, bodily fluids are rapidly transported through the pores towards the inner region of the absorbent material. Furthermore, having relatively narrow pores acts as a barrier against backflow of bodily fluids already absorbed by the top sheet towards the skin. In addition, narrow pores reduce the risk of pressure marks on the wearer's skin.

[0147] Therefore, the above-mentioned top sheet provides improved fluid handling characteristics, such as reduced re-wetting of the absorbent article onto the surface facing the wearer, and better liquid capture.

[0148] When the majority of the pores are hydrophilic, the top sheet may have a discharge and uptake of less than 2 g / g at a 30 cm water column, according to the capillary discharge test method described below in this specification.

[0149] Preferably, the top sheet has an evacuation uptake of less than 1.5 g / g at a 30 cm water column, according to the capillary evacuation test method. More preferably, the top sheet may have an evacuation uptake of less than 1 g / g at a cm water column, according to the capillary evacuation test method.

[0150] The hydrophobic first layer and the hydrophilic pore-containing top sheet allow for the rapid passage of bodily fluids through their thickness into the inner region of the absorbent article.

[0151] Top sheet parameters: The top sheet of the present invention has a runoff volume of less than 40% according to the runoff test method. Preferably, the top sheet has a runoff volume of less than 20% according to the runoff test method. More preferably, the top sheet has a runoff volume of less than 15% according to the runoff test method.

[0152] The leakage test method replicates the usage conditions when a wearer of an absorbent item urinates bodily fluids such as urine onto the top sheet of the absorbent item. A large amount of leakage indicates that the urinated bodily fluid is not absorbed by the top sheet, resulting in leakage, for example, on the posterior lumbar region or the anterior lumbar region of the absorbent item.

[0153] When using the top sheet of the present invention, the amount of bodily fluid leakage is relatively small. Therefore, when the top sheet of the present invention is used in absorbent articles, the risk of leakage on the posterior or anterior lumbar region of the absorbent article is reduced.

[0154] The first layer in three dimensions According to Figure 2, the first layer 1 may include a plurality of protrusions 9. The first layer 1 includes a plurality of holes 5. The first layer 1 includes land regions 8 between most of the holes 5. The land regions may be substantially flat regions. Preferably, the land regions 8 are flat regions.

[0155] Most of the projection 9 may project from the land region 8 of the first layer 1 of the top sheet 24, forming a base 16 and an opposing distal portion 17 from the land region 8. The opposing distal portion 17 of the projection 9 may extend to a distal end that forms a apical peak spaced apart from the base of the projection 9. The base 16 of most of the projection 9 may be defined such that the outer circumference for a circular projection is circular, and each projection begins to project outward from the land region 8 of the first layer 1.

[0156] Most of the protruding portion 9 may have a first height in the Z direction.

[0157] The first layer 1 may have a first surface 3 and a second surface 4. Most of the projection 9 may be located on the first surface 3 of the first layer 1. Most of the projection 9 may extend outward from the first surface 3 of the first layer 1.

[0158] Multiple protrusions 9 can be uniformly distributed on the first surface 3 of the first layer 1. Most of the protrusions 9 may be provided over the entire surface of the first layer 1, or they may be provided on only a portion of the first layer 1.

[0159] Most of the protruding portion 9 may be surrounded by a plurality of land regions 8 and / or a plurality of holes 5.

[0160] Most of the protruding portion 9 and the land area 8 do not need to be oriented in a direction parallel to the MD (machine direction).

[0161] Multiple protrusions 9 can impart a three-dimensional shape to the first layer 1. Multiple land regions 8, multiple holes 5, and multiple protrusions 9 can form a three-dimensional surface on the first surface 3 of the first layer 1 of the top sheet 24.

[0162] Alternatively, though less desirable, the protrusions 9 may extend outward from the second surface 4 of the first layer 1. In this case, the protrusions 9 may be named “recesses,” as described below. The multiple land regions 8, the multiple holes 5, and the multiple protrusions 9 may form a three-dimensional surface on the second surface 4 of the first layer 1 of the top sheet 24.

[0163] Most of the protruding portion 9 may be hollow.

[0164] When viewed from the first surface 3 of the first layer 1, most of the protrusions 9 may protrude in the same direction from the land region 8 of the first layer 1.

[0165] When the top sheet described herein is incorporated into an absorbent article, the multiple protrusions may protrude toward the wearer's skin and detach from the absorbent core of the absorbent article during use.

[0166] Alternatively, though less preferable, when the top sheet described herein is incorporated into an absorbent article, the multiple protrusions may project toward the absorbent core of the absorbent article.

[0167] From the cross-sectional view, that is, when viewed from the Z direction, most of the protruding portion 9 can have any suitable shape, including but not limited to cylindrical, bulbous, conical, and mushroom shapes.

[0168] When viewed from above, the majority of the projection 9 may have any suitable shape, including, but not limited to, circular, diamond-shaped, rounded diamond-shaped, American football-shaped, egg-shaped, clover-shaped, triangular, teardrop-shaped, and elliptical projections. Preferably, the majority of the projection 9 has a dome shape.

[0169] Most of the protruding portion 9 may form one or more graphics as a single unit. Having graphics makes it easier to give caregivers the understanding that the absorbent material can absorb a large amount of liquid excrement.

[0170] Furthermore, the majority of the protruding portion 9 may form one or more graphics, such as a logo, for example, the Pampers Heart logo.

[0171] Two or more adjacent protrusions 9 may be separated by one or more land regions 8 and / or one or more holes 5 in a direction substantially perpendicular to the longitudinal axis of the first layer 1, or in a direction substantially parallel to the longitudinal axis of the first layer 1.

[0172] The majority of the protrusions 9 extending outward from the first surface 3 of the first layer 1 may represent at least 20%, at least 30%, at least 40%, at least 50%, at least 70%, at least 80%, but not exceeding 95%, of the total area of ​​the first layer 1 of the top sheet 24.

[0173] Most of the protruding portion 9 may have a height in the Z direction within the range of approximately 300 μm to approximately 6000 μm, preferably approximately 500 μm to approximately 5000 μm, and more preferably approximately 750 μm to approximately 3000 μm.

[0174] Most of the protrusion 9 may include an inner void volume 14, which is a portion of the protrusion that contains little to no fibers. The void volume 14 may improve the breathability of the top sheet. Most of the protrusion 9 may provide a void volume for receiving bodily fluids.

[0175] When the top sheet 24 described herein is incorporated into an absorbent article, the top sheet may be in close contact with a lower layer, such as a distribution layer. The lower layer may be made of dry fibers of an uncompacted dry fiber structure or a wet fiber structure. The void volume 14 of the protrusion 9 may allow feces to be absorbed and trapped within it.

[0176] The majority of the projection 9 can be defined by the projection base width WB1 of the base 16, which forms an opening measured from the two side walls of the inner portion of the base 16. The majority of the projection 9 can be defined by the width WD2 of the inner void volume 14, which is the maximum inner width measured between the two side walls of the inner projection, or the maximum diameter of the side walls of the inner projection, when the distal portion 17 is substantially circular in shape. The maximum inner width WD2 of the void volume 14 on the opposite distal portion 17 may be greater than the projection base width WB1 of the base 16 of the projection 9. The projection base width WB1 of the base 16 for the majority of the projection 9 can be in the range of 0.5 mm to 15 mm, or 0.5 mm to 10 mm, or 0.5 mm to 5 mm, or 0.5 mm to 3 mm. The dimensions of the projection base width WB1 of the base 16 and the width WD2 of the distal portion 17 can be measured on a micrograph.

[0177] This three-dimensional first layer of the top sheet provides the top sheet with greater flexibility. Furthermore, the protrusions inherently create space between the wearer's skin and bodily fluids, thus helping to keep the wearer's skin separate from bodily fluids within the land area.

[0178] The same properties as described above regarding the hydrophobicity, pore width, and hydrophilicity of the pores of the first layer are applied to the three-dimensional first layer of the top sheet.

[0179] According to Figure 3, the first layer 1 may include a plurality of protrusions 9 projecting outward from the first surface 3 of the first layer 1, or a plurality of recesses 13 projecting outward from the second surface 4 of the first layer 1.

[0180] Alternatively, the first layer 1 may include a plurality of protrusions 9 projecting outward from the first surface 3 of the first layer 1, and a plurality of recesses 13 projecting outward from the second surface 4 of the first layer 1.

[0181] The term "recessed portion" refers to the protruding portion of the top sheet that separates from the wearer's skin when the top sheet is incorporated into an absorbent material.

[0182] The first layer 1 may include a plurality of protrusions 9, a plurality of holes 5, a plurality of recesses 13, and a plurality of land regions 8.

[0183] Multiple land regions 8, multiple depressions 13, multiple holes 5, and multiple protrusions 9 can together form a three-dimensional surface on the first side portion 3 of the first layer 1.

[0184] Alternatively, the first layer may include a plurality of depressions 13, a plurality of holes 5, and a plurality of land regions 8. The plurality of land regions 8, the plurality of depressions 13, and the plurality of holes 5 may together form a three-dimensional surface on the second side portion 4 of the first layer 1.

[0185] Multiple recessed portions 13 can be separated by one or more land areas 8, one or more holes, and / or one or more protrusions 9.

[0186] The holes 5 in the first layer may be located between most of the recessed portions 13 of the first layer 1 and / or within most of the recessed portions 13 of the first layer 1. Alternatively, some of the recessed portions 13 may not have holes 5 within them.

[0187] In most of the recessed area 13, a hole 5 can be defined at the most distal location from the land area 8.

[0188] The land area 8 may be located midway between adjacent protrusions 9, adjacent recesses 13, and / or adjacent holes 5.

[0189] The land region 8 may form a substantially continuous grid through the first layer 1 of the top sheet 24, while the protrusions 9, holes 5 and / or recesses 13 may be separate elements distributed within the grid throughout the first layer 1 of the top sheet 24.

[0190] The majority of the recessed portion may have a height in the Z direction within the range of approximately 200 μm to approximately 3000 μm, preferably approximately 300 μm to approximately 2000 μm, more preferably approximately 500 μm to approximately 1500 μm, and even more preferably approximately 700 μm to approximately 1000 μm.

[0191] The height of the protruding portion 9 in the Z direction may be equal to or greater than the height of the recessed portion 13 in the Z direction.

[0192] The first layer and the second layer: The top sheet may have a second layer that is in a relationship with the first layer. The first layer corresponds to the first layer as described above, and all the embodiments described above for the first layer are equally applicable to the first layer in a top sheet that includes the first and second layers.

[0193] The second layer may be a woven or nonwoven web of natural fibers, synthetic fibers, or a combination of natural and synthetic fibers. Preferably, the second layer is a nonwoven web of natural fibers, synthetic fibers, or a combination of natural and synthetic fibers.

[0194] The lists of synthetic and natural fibers correspond to the lists disclosed above for the top sheet.

[0195] Preferably, the synthetic fiber is selected from the group consisting of polypropylene, polyethylene, polyester, polyethylene terephthalate, polybutylene terephthalate, polyamide, polylactic acid, and combinations thereof.

[0196] Synthetic fibers can be single-component fibers, multi-component fibers such as two-component fibers, or combinations thereof.

[0197] Preferably, the natural fiber is selected from the group consisting of cotton fiber, bamboo fiber, or a mixture thereof. Preferably, the natural fiber is cotton fiber.

[0198] The fibers may have any suitable denier or denier range, and / or fiber length or fiber length range.

[0199] The second layer may have multiple holes. The first layer may have multiple holes. The second layer may have multiple holes that are at least partially aligned with the holes of the first layer. The holes of the first layer may correspond to the holes of the second layer. All the holes of the second layer can be aligned with the holes of the first layer. This can be achieved by simultaneously forming the holes of the first and second layers after the first and second layers have been placed facing each other.

[0200] Multiple pores in the second layer can be uniformly distributed within the second layer.

[0201] The first layer may at least partially penetrate the second layer of the top sheet at the pore. Alternatively, the first layer may penetrate the second layer of the top sheet at the pore. This property can be facilitated by following the process described below.

[0202] Alternatively, the first layer does not have to penetrate the second layer of the top sheet in the hole. This property can be formed by an alternative process, such as the process described in U.S. Patent No. 5,628,097, or by using a hole puncher.

[0203] The multiple holes in the first and second layers may be simple openings without side walls.

[0204] Alternatively, the plurality of holes of the present invention may include side walls that extend outward from and beyond the second surface of the first layer, and that extend outward from and beyond the second surface of the second layer.

[0205] When the top sheets described herein are incorporated into an absorbent article, the orientation of these sidewalls may be toward the absorbent core of the absorbent article, or, less preferably, toward the wearer's skin during use of the article.

[0206] The extent to which the side walls of the holes in the first and second layers extend should be at least 0.1 mm beyond the first surface of the first layer, preferably at least 0.2 mm beyond the first surface of the first layer. The side walls of the holes in the first and second layers may form a funnel or channel.

[0207] Referring to Figure 4a, the top sheet 24 may include a first layer 1 and a second layer 2. The first layer may include a first surface 3 and a second surface 4. The second layer may include a first surface 10 and a second surface 11.

[0208] The first surface 10 of the second layer 2 may come into contact with the second surface 4 of the first layer 1.

[0209] When the top sheet described herein is incorporated into an absorbent article, the first surface 10 of the second layer 2 faces the wearer's body, and the second surface 11 of the second layer 2 faces the back sheet.

[0210] When the top sheet described herein is incorporated into an absorbent article, the first layer 1 faces the wearer's body during use of the article, and the second layer 2 faces the back sheet.

[0211] The second layer 2 may have a plurality of holes 5. The first layer 1 has a plurality of holes 5. The holes 5 in the first and second layers may have a top and a bottom.

[0212] The second layer 2 may have a plurality of holes 5 that are at least partially aligned with or fully aligned with the holes 5 of the first layer 1. The holes 5 of the first layer 1 and the second layer 2 may be the same. The plurality of holes 5 of the second layer 2 may have the same width and / or length as the holes 5 of the first layer 1.

[0213] The side walls of the holes in the first layer 1 may be shorter than the side walls of the holes in the second layer 2 within the multiple holes 5, as shown in Figure 4b. Therefore, at the bottom of the side walls of the holes 5, the holes 5 can be formed only by the second layer 2.

[0214] The first layer 1 includes land regions 8 between most of the holes 5. The second layer 2 may include land regions 12 between most of the holes 5. The land regions 8 of the first layer 1 may be aligned with the land regions 12 of the second layer 2.

[0215] The land region 8 of the first layer 1 and the land region 12 of the second layer 2 can completely surround the holes 5 of the first layer 1 and the second layer 2.

[0216] The land region 8 of the first layer 1 and the land region 12 of the second layer 2 may be substantially flat regions. Preferably, the land region 8 of the first layer 1 and the land region 12 of the second layer 2 are flat regions.

[0217] The land regions (8, 12) may together form a substantially continuous grid through the first layer 1 and the second layer 2, while the holes 5 may be separate elements distributed throughout the entire first layer 1 and the second layer 2.

[0218] The first layer 1 does not have to have any protrusions. This means that the first layer does not have to include any raised regions away from the pores that may extend outward beyond the surface of the first layer. However, it is preferable that the first layer has a plurality of protrusions.

[0219] The second layer 2 does not have to have any protrusions. This means that the second layer does not have to include any raised regions away from the hole that may extend outward beyond the surface of the second layer. It is preferable that the second layer has no protrusions and that the region of the second layer 2 that coincides with the protrusions of the first layer is flat. Thus, a hollow space may be formed between the protrusions of the first layer and the second layer.

[0220] The first and second layers may be in contact with each other and may be joined to each other in the land regions (8, 12) and / or holes 5.

[0221] The first and second layers may be joined together or attached to each other by mechanical bonding, adhesive bonding, pressure bonding, thermal bonding, passing a heated gas through both layers, or other methods of joining to form a top sheet known in the art.

[0222] Preferably, the first layer is attached to the second layer within the bonding area by a hot-melt adhesive.

[0223] The bonding region may be located in the land region (8, 12) and / or in hole 5.

[0224] The first and second layers can be bonded together with a hot melt adhesive applied in the form of a helical, slot coating, or spray. The basis weight of the hot melt adhesive is at least 1 g / m². 2 Preferably at least 5 g / m 2 , more preferably at least 7 g / m 2 This is possible. The basis weight of the hot melt adhesive is 20 g / m². 2 The following are possible:

[0225] Hot melt adhesives can be hydrophilic. Hydrophilic hot melt adhesives may be selected from the group consisting of styrene-butadiene-styrene (SBS), styrene-isoprene-styrene (SIS), styrene-ethylene-butadiene-styrene (SEBS), styrene-ethylene-propylene-styrene (SEPS), and combinations thereof, or other hot melt adhesives known in the art.

[0226] Having a hydrophilic hot-melt adhesive to attach the first and second layers can help to have a low amount of liquid leakage. Therefore, when the top sheet of the present invention is used in absorbent articles, the risk of leakage over the posterior or anterior lumbar region of the absorbent article is reduced.

[0227] When the hot melt adhesive is applied to the land areas of the first and / or second layers, the hot melt adhesive may also reach the tops and / or side walls of the holes.

[0228] On one side, the first surface land region contact angle on the land region of the first surface of the first layer between most of the holes is greater than 70° according to the contact angle test method. The second surface land region contact angle on the land region of the second surface of the second layer between most of the holes may be 70° or less according to the contact angle test method.

[0229] The width of most of the holes 5 in the first layer 1 and the second layer 2 may be less than 1.5 mm, less than 1.2 mm, less than 1 mm, or less than 0.8 mm, according to the hole size test method. The width of most of the holes may be 0.5 mm or less, according to the hole size test method described below in this specification. When such holes are present, most of the holes 5 in the first layer 1 and the second layer 2 may be hydrophilic.

[0230] A hydrophilic treatment can be applied to most of the pores 5. The hydrophilic treatment may be a hydrophilic polymer. The hydrophilic treatment may be a hydrophilic surfactant such as BASF's Pluronic® surfactant, BASF's Tetronic® surfactant, or a combination thereof.

[0231] Most of the pores 5 in the first layer 1 and the second layer 2 may contain a hydrophilic surfactant.

[0232] Hydrophilic treatment can be applied to most of the holes via the perforation pin process as described above, via the printing process, or via a hydrophilic hot-melt adhesive between the two layers of the top sheet.

[0233] At least 20% of the pores in the first and second layers may be hydrophilic, preferably at least 30% of the pores in the first and second layers may be hydrophilic, and more preferably at least 50%, or at least 75%, or at least 95% of the pores in the first and second layers may be hydrophilic. Even more preferably, 100% of the pores in the first and second layers are hydrophilic.

[0234] The hole contact angle over most of the hole may be 70° or less according to the contact angle test method. Specifically, the hole contact angle over most of the top and bottom of the hole may be 70° or less according to the contact angle test method.

[0235] Three-dimensional first and second layers Referring to Figure 5, the top sheet may include a three-dimensional first layer 1 and a flat second layer 2. The first layer may include a first surface 3 and a second surface 4. The second layer may include a first surface 10 and a second surface 11.

[0236] The first surface 10 of the second layer 2 can be joined to the second surface 4 of the first layer 1 by contact.

[0237] When the top sheet described herein is incorporated into an absorbent article, the first surface 10 of the second layer 2 faces the wearer's body during use of the article, and the second surface 11 of the second layer 2 faces the back sheet.

[0238] When the top sheet described herein is incorporated into an absorbent article, the first layer 1 faces the wearer's body during use of the article, and the second layer 2 faces the back sheet.

[0239] The second layer 2 may have a plurality of holes 5. The first layer 1 has a plurality of holes 5. The holes 5 of the first layer and the optional holes of the second layer may have a top and a bottom.

[0240] The second layer 2 may have a plurality of holes 5 that are at least partially aligned with, or fully aligned with, the holes 5 of the first layer 1. The holes 5 of the first layer 1 and the second layer 2 may be the same. The plurality of holes 5 of the second layer 2 may have at least partially, or all, the same width and / or length as the holes 5 of the first layer 1.

[0241] The side walls of the holes in the first layer 1 may be shorter than the side walls of the holes in the second layer 2. Therefore, at the bottom of hole 5, hole 5 can be formed solely by the second layer 2.

[0242] The first layer 1 may have a plurality of protrusions 9. The first layer 1 includes a land region 8 which may be a substantially flat region. Preferably, the land region 8 is a flat region.

[0243] Most of the protruding portion 9 and the land area 8 do not need to be oriented in a direction parallel to the MD (machine direction).

[0244] Most of the projection 9 may protrude from the land region 8 of the first layer 1 of the top sheet 24, forming a base and an opposing distal portion from the land region 8. The opposing distal portion of the projection 9 may extend to a distal end that forms a apical peak spaced apart from the base of the projection 9.

[0245] Most of the protrusion 9 may be located on the first surface 3 of the first layer 1. Most of the protrusion 9 may be surrounded by a plurality of land regions 8 and / or a plurality of holes 5. The plurality of land regions 8, the plurality of holes and the plurality of protrusions may impart a three-dimensional shape to the first layer 1 of the top sheet 24.

[0246] Multiple protrusions 9 can be uniformly distributed on the first surface 3 of the first layer 1.

[0247] Most of the protrusion 9 may be hollow. When viewed from the first surface 3 of the first layer 1, most of the protrusion 9 may protrude in the same direction from the land region 8 of the first layer 1.

[0248] When the top sheet described herein is incorporated into an absorbent article, the multiple protrusions may protrude away from the absorbent core of the absorbent article.

[0249] Alternatively, though less preferable, when the top sheet described herein is incorporated into an absorbent article, the multiple protrusions may project toward the absorbent core of the absorbent article.

[0250] From the cross-sectional view, that is, when viewed from the Z direction, most of the protruding portion 9 can have any suitable shape, including but not limited to cylindrical, bulbous, conical, and mushroom shapes.

[0251] When viewed from above, most of the projections 9 include, but are not limited to, circular, diamond-shaped, rounded diamond-shaped, American football-shaped, egg-shaped, clover-shaped, triangular, teardrop-shaped, and elliptical projections, and may have any other suitable shape.

[0252] Most of the protruding portion 9 may form one or more graphics as a single unit. Having graphics makes it easier to give caregivers the understanding that the absorbent material can absorb a large amount of liquid excrement.

[0253] Furthermore, most of the protrusions 9 may together form one or more graphics, such as a logo, for example, the Pampers Heart logo.

[0254] The second layer 2 may include a land area 12 between most of the holes 5. The land area 8 of the first layer 1 may be aligned with the land area 12 of the second layer 2.

[0255] The land area 8 of the first layer 1 and the land area 12 of the second layer 2 may completely surround the holes 5 of the first layer 1 and the second layer 2.

[0256] The land area 8 of the first layer 1 and the land area 12 of the second layer 2 may be substantially flat areas. Preferably, the land area 8 of the first layer 1 and the land area 12 of the second layer 2 are flat areas.

[0257] The second layer 2 may not have protrusions, and the area of the second layer that coincides with the protrusions of the first layer may be flat.

[0258] The first layer 1 and the second layer 2 may contact each other between at least most of the protrusions 9 of the first layer 1. The first layer and the second layer may contact each other at the land areas (8, 12) and / or the holes 5.

[0259] If the second layer does not have protrusions, the first layer and the second layer may not contact each other within the protrusion area.

[0260] Most of the protrusions 9 may include an inner void volume 14 that is a part of the protrusion that contains little or no fiber. The void volume 14 may improve the breathability of the topsheet. Most of the protrusions 9 may provide a void volume for receiving body fluids.

[0261] The first and second layers may be joined together or attached to each other by mechanical bonding, adhesive bonding, pressure bonding, thermal bonding, passing a heated gas through both layers, or other methods known in the art to bond and form a top sheet.

[0262] Preferably, the first layer is attached to the second layer within the bonding area by a hot-melt adhesive.

[0263] The bonding region may be located in the land region (8, 12) and / or in hole 5.

[0264] The first and second layers can be bonded together with a hot melt adhesive applied in the form of a helical, slot coating, or spray. The basis weight of the hot melt adhesive is at least 1 g / m². 2 Preferably at least 5 g / m 2 , more preferably at least 7 g / m 2 It is possible.

[0265] Hot melt adhesives can be hydrophilic. Hydrophilic hot melt adhesives can be selected from the group consisting of styrene-butadiene-styrene (SBS), styrene-isoprene-styrene (SIS), styrene-ethylene-butadiene-styrene (SEBS), styrene-ethylene-propylene-styrene (SEPS), and combinations thereof, or other hot melt adhesives known in the art.

[0266] Having a hydrophilic hot-melt adhesive to attach the first and second layers can help to have a low amount of liquid leakage. Therefore, when the top sheet of the present invention is used in absorbent articles, the risk of leakage over the posterior or anterior lumbar region of the absorbent article is reduced.

[0267] When the hot melt adhesive is applied to the land areas of the first and / or second layers, the hot melt adhesive may also reach the tops and / or side walls of the holes.

[0268] On one side, the first surface land region contact angle on the land region of the first surface of the first layer between most of the holes is greater than 70° according to the contact angle test method. The second surface land region contact angle on the land region of the second surface of the second layer between most of the holes may be 70° or less according to the contact angle test method.

[0269] The width of most of the holes 5 in the first layer 1 and the second layer 2 may be less than 1.5 mm, less than 1.2 mm, less than 1 mm, or less than 0.8 mm, according to the hole size test method. The width of most of the holes may be 0.5 mm or less, according to the hole size test method described below in this specification. With such holes, most of the holes 5 in the first layer 1 and the second layer 2 may be hydrophilic.

[0270] A hydrophilic treatment can be applied to most of the pores 5. The hydrophilic treatment may be a hydrophilic polymer. The hydrophilic treatment may be a hydrophilic surfactant such as BASF's Pluronic® surfactant, BASF's Tetronic® surfactant, or a combination thereof.

[0271] Most of the pores 5 in the first layer 1 and the second layer 2 may contain a hydrophilic surfactant.

[0272] Hydrophilic treatment can be applied to most of the holes via the perforation pin process, via the printing process, or via a hydrophilic hot-melt adhesive between the two layers of the top sheet.

[0273] At least 20% of the pores in the first and second layers may be hydrophilic, preferably at least 30% of the pores in the first and second layers may be hydrophilic, and more preferably at least 50%, or at least 75%, or at least 95% of the pores in the first and second layers may be hydrophilic. Even more preferably, 100% of the pores in the first and second layers are hydrophilic.

[0274] The pore contact angle on most of the pores can be 70° or less according to the contact angle test method. Specifically, the pore contact angle on the top and bottom of most of the pores can be 70° or less according to the contact angle test method.

[0275] The width of most of the pores 5 in the first layer 1 and the second layer 2 can be less than 1.5 mm, or less than 1.2 mm, or less than 1 mm, or less than 0.8 mm according to the pore size test method. The width of most of the pores can be 0.5 mm or less according to the pore size test method described below in this specification. With such pores, most of the pores can be hydrophilic as described above.

[0276] Three-dimensional topsheet Referring to FIG. 6, the topsheet 24 can be a laminate including the first layer 1 as described above and the second layer 2 as described above in a facing relationship. In other words, the first layer 1 and the second layer 2 are joined to form a laminate.

[0277] The first layer 1 can have a first surface 3 and a second surface 4. The second layer 2 can have a first surface 10 and a second surface 11.

[0278] The first layer 1 and the second layer 2 can be aligned in a facing relationship such that the second surface 4 of the first layer 1 contacts the first surface 10 of the second layer 2.

[0279] When the topsheet described in this specification is incorporated into an absorbent article, the first layer 1 faces the wearer's body, and the second layer 2 faces the backsheet.

[0280] The first layer 1 and the second layer can be mechanically deformed simultaneously and combined to provide a topsheet having protrusions. This means that both the first layer 1 and the second layer 2 can be mechanically deformed and combined simultaneously.

[0281] The first layer 1 can include a plurality of protrusions 9. The second layer can include a plurality of protrusions 9.

[0282] Multiple protrusions 9 of the first layer can be at least partially aligned with, or fully aligned with, multiple holes 9 of the second layer 2. The protrusions 9 of the first layer 1 and the second layer 2 may be the same.

[0283] The protrusion 9 is formed from the fibers of the first layer 1 and may also be formed at least partially from the fibers of the second layer 2 of the top sheet 24.

[0284] If the second layer similarly includes protrusions, the multiple protrusions 9 can impart a three-dimensional shape to the second layer 2. Simultaneously, the multiple protrusions 9 can impart a three-dimensional shape to the first layer 1. The top sheet 24 may be a three-dimensional top sheet.

[0285] As shown in Figure 6, the majority of the projection 9 may include a base 16 having a projection base width and forming an opening, a distal portion 17 on the opposite side, and one or more side walls 15 between the base 16 and the distal portion 17 of the majority of the projection 9. The base 16, the distal portion 17, and the one or more side walls 15 may be formed of fibers such that the majority of the projection 9 has only an opening in the base 16.

[0286] The majority of the protrusions 9 extending outward from the first surface 3 of the first layer 1 may represent at least 20%, at least 30%, at least 40%, at least 50%, at least 70%, at least 80%, but not exceeding 95%, of the total area of ​​the first layer 1 of the top sheet 24.

[0287] The second layer 2 may have a plurality of holes 5. The first layer 1 has a plurality of holes 5. The holes 5 may have a top and a bottom.

[0288] The second layer 2 may have a plurality of holes 5 that are at least partially aligned with the holes 5 of the first layer 1. The holes 5 of the first layer 1 and the second layer 2 may be the same. The plurality of holes 5 of the second layer 2 may have the same width and / or length as the holes 5 of the first layer 1.

[0289] The first layer 1 may be shorter than the second layer 2 within the multiple holes 5. Therefore, at the bottom of the hole 5, the hole 5 may be formed solely by the second layer 2.

[0290] The first layer 1 may include a land region 8 which may be a substantially flat region. The second layer 2 may include a land region 12 which may be a substantially flat region. The land region 8 of the first layer 1 may be aligned with the land region 12 of the second layer 2. Preferably, the land region 8 of the first layer 1 and the land region 12 of the second layer 2 are flat regions. The second layer may also have flat regions within these regions where the second layer coincides with the projection of the first layer.

[0291] Most of the protruding portion 9 may protrude from the land region 8 of the first layer 1 and from the land region 12 of the second layer 2.

[0292] Most of the protruding portion 9 and the land area 8 do not need to be oriented in a direction parallel to the MD (machine direction).

[0293] Most of the protruding portion 9 may be surrounded by a plurality of land regions (8, 12) and / or a plurality of holes 5.

[0294] Multiple protrusions 9 can be uniformly distributed along the first surface 3 of the first layer 1.

[0295] Most of the protrusion 9 may be hollow. When viewed from the first surface 3 of the first layer 1, most of the protrusion 9 may protrude in the same direction from the land region 8 of the first layer 1.

[0296] When the top sheet described herein is incorporated into an absorbent article, the multiple protrusions may protrude away from the absorbent core of the absorbent article.

[0297] Alternatively, when the top sheet described herein is incorporated into an absorbent article, the multiple protrusions may project toward the absorbent core of the absorbent article.

[0298] From the cross-sectional view, that is, when viewed from the Z direction, most of the protruding portion 9 can have any suitable shape, including but not limited to cylindrical, bulbous, conical, and mushroom shapes.

[0299] When viewed from above, the majority of the projection 9 may have any suitable shape, including, but not limited to, circular, diamond-shaped, rounded diamond-shaped, American football-shaped, egg-shaped, clover-shaped, triangular, teardrop-shaped, and elliptical projections. Preferably, the majority of the projection 9 has a dome shape.

[0300] Most of the protruding portion 9 may form one or more graphics as a single unit. Having graphics makes it easier to give caregivers the understanding that the absorbent material can absorb a large amount of liquid excrement.

[0301] Furthermore, the majority of the protruding portion 9 may form one or more graphics, such as a logo, for example, the Pampers Heart logo.

[0302] Most of the protrusion 9 can be made by engaging the first layer 1 with the second layer 2, such as by having the first layer 1 and the second layer 2 fit together in a coordinated manner.

[0303] The first and second layers may be joined together or attached to each other by mechanical bonding, adhesive bonding, pressure bonding, thermal bonding, passing a heated gas through both layers, or other methods of joining to form a top sheet known in the art.

[0304] Preferably, the first layer is attached to the second layer within the bonding area by a hot-melt adhesive.

[0305] The bonding regions may be located in the land regions (8, 12), the projection 9, and / or the hole 5.

[0306] The first and second layers can be bonded together with a hot melt adhesive applied in the form of a helical, slot coating, or spray. The basis weight of the hot melt adhesive is at least 1 g / m². 2 Preferably at least 5 g / m 2 , more preferably at least 7 g / m 2 It is possible.

[0307] Hot melt adhesives can be hydrophilic. Hydrophilic hot melt adhesives may be selected from the group consisting of styrene-butadiene-styrene (SBS), styrene-isoprene-styrene (SIS), styrene-ethylene-butadiene-styrene (SEBS), styrene-ethylene-propylene-styrene (SEPS), and combinations thereof, or other hot melt adhesives known in the art.

[0308] When the hot melt adhesive is applied to the land areas of the first and / or second layers, the hot melt adhesive may also reach the tops and / or side walls of the holes.

[0309] Most of the protrusion 9 may include an inner void volume 14, which is a portion of the protrusion that contains little to no fibers. The void volume 14 may improve the breathability of the top sheet. Most of the protrusion 9 may provide a void volume for receiving bodily fluids.

[0310] When the top sheet 24 described herein is incorporated into an absorbent article, the top sheet may be in close contact with a lower layer, such as a distribution layer. The lower layer may be made of dry fibers of an uncompacted dry fiber structure or a wet fiber structure. The void volume 14 of the protrusion 9 may allow feces to be absorbed and trapped within it.

[0311] The majority of the projection 9 can be defined by the projection base width WB1 of the base 16, which forms an opening measured from the two side walls of the inner portion of the base 16. The majority of the projection 9 can be defined by the width WD2 of the inner void volume 14, which is the maximum inner width measured between the two side walls of the inner projection, or the maximum diameter of the side walls of the inner projection, when the distal portion 17 is substantially circular in shape. The maximum inner width WD2 of the void volume 14 on the opposite distal portion 17 may be greater than the projection base width WB1 of the base 16 of the projection 9. The projection base width WB1 of the base 16 for the majority of the projection 9 can be in the range of 0.5 mm to 15 mm, or 0.5 mm to 10 mm, or 0.5 mm to 5 mm, or 0.5 mm to 3 mm. The dimensions of the projection base width WB1 of the base 16 and the width WD2 of the distal portion 17 can be measured on a micrograph.

[0312] The first layer 1 and the second layer 2 may include a plurality of protrusions 9 projecting outward from the first surface 3 of the first layer 1, or a plurality of recesses 13 projecting outward from the second surface 11 of the second layer 2.

[0313] Alternatively, the first layer 1 and the second layer 2 may include a plurality of protrusions 9 projecting outward from the first surface 3 of the first layer 1, and a plurality of recesses 13 projecting outward from the second surface 11 of the second layer 2.

[0314] The term "recessed portion" refers to the protruding portion of the top sheet that separates from the wearer's skin when the top sheet is incorporated into an absorbent material.

[0315] The first layer 1 and the second layer 2 may include a plurality of recesses, a plurality of holes 5, a plurality of protrusions 9, and a plurality of land regions (8, 12).

[0316] Alternatively, the first layer 1 and the second layer 2 may include a plurality of depressions, a plurality of holes 5, and a plurality of land regions (8, 12).

[0317] The holes 5 may be located between and / or within most of the depressions. Some depressions may not have holes 5 within them.

[0318] In most of the depressed area, a hole 5 can be defined at the most distal location from the land area 12.

[0319] The land area 12 may be located between adjacent protrusions 9, adjacent recesses, and / or adjacent holes 5.

[0320] Multiple depressions may be separated by one or more land areas 12, one or more holes, and / or one or more protrusions 9.

[0321] Multiple depressions in the first layer can be aligned with multiple depressions in the second layer. Multiple depressions in the first and second layers may be the same.

[0322] The first layer and the second layer may come into contact with each other in the depression.

[0323] The majority of the recessed portion may have a height in the Z direction within the range of approximately 200 μm to approximately 3000 μm, preferably approximately 300 μm to approximately 2000 μm, more preferably approximately 500 μm to approximately 1500 μm, and even more preferably approximately 700 μm to approximately 1000 μm.

[0324] The height of the protruding portion 9 in the Z-direction may be greater than or equal to the height of the recessed portion in the Z-direction.

[0325] The contact angle of the first surface land region on the first surface of the first layer between most of the holes can be greater than 70° according to the contact angle test method.

[0326] The contact angle of the second surface land region on the second surface of the second layer between most of the holes may be 70° or less according to the contact angle test method.

[0327] The width of most of the holes 5 in the first layer 1 and the second layer 2 may be less than 1.5 mm, less than 1.2 mm, less than 1 mm, or less than 0.8 mm, according to the hole size test method. The width of most of the holes may be 0.5 mm or less, according to the hole size test method described below in this specification. With such holes, most of the holes 5 in the first layer 1 and the second layer 2 may be hydrophilic.

[0328] A hydrophilic treatment can be applied to most of the pores 5. The hydrophilic treatment may be a hydrophilic polymer. The hydrophilic treatment may be a hydrophilic surfactant such as BASF's Pluronic® surfactant, BASF's Tetronic® surfactant, or a combination thereof.

[0329] Most of the pores 5 in the first layer 1 and the second layer 2 may contain a hydrophilic surfactant.

[0330] Hydrophilic treatment can be applied to most of the holes via the perforation pin process as described above, via the printing process, or via a hydrophilic hot-melt adhesive between the two layers of the top sheet.

[0331] At least 40% of the total pores in the first and second layers may be hydrophilic, preferably at least 50% of the total pores in the first and second layers may be hydrophilic, and more preferably at least 60% of the total pores in the first and second layers may be hydrophilic. Even more preferably, 100% of the total pores in the first and second layers may be hydrophilic.

[0332] The hole contact angle over most of the hole may be 70° or less according to the contact angle test method. Specifically, the hole contact angle over most of the top and bottom of the hole may be 70° or less according to the contact angle test method.

[0333] Mechanical deformation, resulting in protrusions and holes Using several different methods known in the art, the perforated nonwoven fabrics of this disclosure, i.e., perforated top sheets, and three-dimensional nonwoven materials having holes can be created. These methods are described in International Application No. 2017 / 156200, filed by Procter and Gamble Company and published on 14 September 2017, which is incorporated herein by reference.

[0334] A three-dimensional perforated first layer of the top sheet of the present disclosure, or a laminate of the first and second layers of the top sheet of the present disclosure, can also be produced rapidly and industrially as described below.

[0335] Figure 7 is a schematic diagram of an example of a process for forming the substrate of the present disclosure. Figure 8 is a diagram of the interlocking engagement of a portion of the first and second rolls. Figure 9 is a diagram of a portion of the first roll. Figure 10 is a diagram of a portion of the second roll.

[0336] Referring to Figures 7 to 10, the first layer of the top sheet of the present disclosure may be formed by passing one or more layer substrates 399 (non-three-dimensional) through a nip 502 formed by two interlocking rolls 504 and 506 to form a three-dimensional substrate 400. The rolls 504 and 506 may be heated. The first roll 504 (in combination with the second roll) may create a hole in the substrate 400, and the second roll 506 (in combination with the first roll) may create a projection in the substrate 400. The first roll 504 may include a plurality of projections 508 extending radially outward from the first roll 504. The first roll 504 may also include a plurality of recesses 510 formed on the radially outer surface of the first roll 504. The second roll 506 may include a plurality of projections 512 extending radially outward from the second roll 506. The second roll 506 may also include a plurality of recesses 514 formed on its radially outer surface. The protrusions 508 on the first roll 504 may have different sizes, shapes, heights, areas, widths, and / or dimensions from the protrusions 512 on the second roll 506. The recesses 510 formed on the first roll 504 may have different sizes, shapes, heights, areas, widths, and / or dimensions from the recesses 514 formed on the second roll 506. The recesses 510 on the first roll 504 may be configured to at least partially receive the protrusions 512, thereby creating protrusions in the substrate 400. Specifically, when the protrusions 512 engage within the recesses 510, a sufficient depth of space remains between the radial surfaces, so the thickness of the substrate at the protrusion is greater than the thickness of the recesses. This feature provides a softer feel and a higher protrusion compared to compressing the portion of the substrate forming the protrusion. The recessed portion 514 of the second roll 506 may be configured to at least partially receive the protrusion 508, thereby creating a hole in the first layer of the top sheet.

[0337] Alternatively, a three-dimensional perforated first layer of the top sheet of the present disclosure, or a laminate of the first and second layers of the top sheet of the present disclosure, can be formed by other means.

[0338] Referring to Figure 11, the first substrate 200 may pass through a pair of rolls named A and B to form the first layer 1 of the present invention. The speed of rolls A and B may be 5 to 600 meters / minute. The temperature range of roll A may be 40 to 200°C. The temperature range of roll B may be 30 to 200°C. Roll A may include a plurality of projections 201 extending radially outward from roll A. Roll A may also include a plurality of recesses 202 formed on the radially outer surface of roll A. The depth of the recesses 202 of roll A may be 0.5 to 10 mm, and the depth of the projections 201 of roll A may be 0.5 to 9 mm. Roll B may include a plurality of projections 203 extending radially outward from roll B. Roll B may also include a plurality of recesses 204 formed on the radially outer surface of roll B. The distal ends of the multiple protrusions 203 of roll B may have the shape of pins 205.

[0339] The protrusion 201 on roll A may have a different size, shape, height, area, width, and / or dimensions from the protrusion 203 on roll B. The recess 202 formed on roll A may have a different size, shape, height, area, width, and / or dimensions from the recess 204 formed on roll B. The recess 202 on roll A may be configured to at least partially receive the protrusion 203 on roll B, thereby creating a protrusion within the first substrate 200. Roll A may include a plurality of holes within the recess area to receive the shape of the pin 205 of the protrusion 203 on roll B. Thus, a plurality of holes 5 are formed in the first substrate 200 between each protrusion of the first substrate 200. After passing through rolls A and B, the first substrate 200 may include a plurality of protrusions 9 and a plurality of holes 5 between each protrusion.

[0340] The second substrate 206 may be provided by a concave roller C. A hot-melt adhesive may be added by the apparatus D to the first surface of the second substrate 206 before it comes into contact with the first substrate 200. Roll C may include a plurality of holes to accommodate the shape of the pins 205 of the projection 203 of roll B.

[0341] The second substrate 206 may pass through rolls C and B and may come into contact with the first substrate 200 at the projection 203 of roll B. Since the projection 203 of roll B may have a pin shape, multiple holes may also be created on the second substrate 206. Multiple holes 5 in the second substrate 206 may be at least partially aligned with the holes 5 in the first substrate 200.

[0342] At the end of the process, a three-dimensional perforated first layer 1 can be obtained, which can contact the second layer 2 between most of the protrusions 9 of the first layer.

[0343] The first base material 200 may also be a first layer 1 and a second layer 2 engaged together between rolls A and B, which are simultaneously mechanically deformed and combined to form the three-dimensional top sheet 24 of the present invention.

[0344] To form a first layer of a top sheet having multiple protrusions, the first layer 1 may also be engaged between first and second forming members and mechanically deformed to form a first layer having a three-dimensional shape. This method is described in International Application No. 2017 / 156203 filed by Procter and Gamble Company, published on 14 September 2017, which is incorporated herein by reference. The first layer may therefore include deformation to form protrusions 9.

[0345] Alternatively, to form a three-dimensional top sheet 24 having a first layer 1 and a second layer 2, the first layer 1 and the second layer 2 may be engaged together between the first and second forming members, simultaneously mechanically deformed and combined to form the top sheet 24. This method is described in International Application No. 2017 / 156203, filed by Procter and Gamble Company and published on 14 September 2017, which is incorporated herein by reference.

[0346] Absorbent articles A typical disposable absorbent article in which the top sheet of the present invention may be used is shown in the form of a diaper 20, which is placed in contact with or near the wearer's body to absorb and contain various excrements discharged from the body, as shown in Figures 12 to 16.

[0347] More specifically, Figure 12 is a plan view of an exemplary diaper 20 in an unfolded state, with a portion of the diaper cut out to more clearly show the structure of the diaper 20. Since the structure of the present invention may be contained within a wide variety of diapers or other absorbent articles, this diaper 20 is shown for illustrative purposes only.

[0348] As shown in Figures 12 and 13, an absorbent article, in this case a diaper, may include a liquid-permeable top sheet 24, a liquid-impermeable back sheet 26, and an absorbent core 28 positioned between the top sheet 24 and the back sheet 26. The absorbent core 28 can absorb and contain the liquid received by the absorbent article and may include absorbent material 60, such as superabsorbent polymer particles 66 and / or cellulose fibers, as well as other absorbent and nonabsorbent materials commonly used in absorbent articles (e.g., thermoplastic adhesives for immobilizing the superabsorbent polymer particles). The absorbent and nonabsorbent materials may be encased within a substrate (e.g., one or more nonwoven fabrics, tissues, etc.) by an upper core cover layer 56 facing the top sheet and a lower cover layer 58 facing the back sheet, etc. Such upper and lower core cover layers may be made of nonwoven fabrics, tissues, etc., and may be attached to each other, for example, continuously or discontinuously along their outer periphery.

[0349] The absorbent core may comprise one or more substrate layers (nonwoven web or tissue paper), superabsorbent polymer particles disposed on one or more substrate layers, and a thermoplastic composition typically disposed on the superabsorbent polymer particles. Typically, the thermoplastic composition is a thermoplastic adhesive material. In one embodiment, the thermoplastic adhesive material forms a fibrous layer that is at least partially in contact with one or more substrate layers, and at least partially in contact with the superabsorbent polymer particles on one or more substrate layers. To enhance the adhesion of the superabsorbent polymer particles and / or the thermoplastic adhesive material to each substrate layer, an auxiliary adhesive may be applied to one or more substrate layers before the superabsorbent polymer particles are applied. The absorbent core may also comprise one or more cover layers such that the superabsorbent polymer particles are contained between one or more substrate layers and one or more cover layers. The one or more substrate layers and cover layers may comprise or consist of a nonwoven web. The absorbent core may further comprise an odor control compound.

[0350] The absorbent core may essentially consist of one or more substrate layers, superabsorbent polymer particles, a thermoplastic composition, an auxiliary adhesive if necessary, a cover layer if necessary, and an odor control compound if necessary.

[0351] The absorbent core may also comprise a mixture of superabsorbent polymer particles and air felt, which can be encapsulated within one or more substrate layers, such as a nonwoven web or tissue paper. Such an absorbent core may comprise 30% to 95% by weight of the absorbent material, or 50% to 95% by weight of superabsorbent polymer particles, and 5% to 70% by weight of the absorbent material, or 5% to 50% by weight of air felt (with respect to these proportions, any surrounding substrate layer is not considered absorbent material). The absorbent core may also not comprise air felt, and may comprise 100% by weight of superabsorbent polymer particles.

[0352] The absorbent articles of the present invention, in particular diapers and pants, may include a trapping layer 52, a distributing layer 54, or a combination thereof (collectively referred to herein as the trapping and distributing system "ADS" 50).

[0353] A hydrophilic hot-melt adhesive may be used to bond the top sheet to the trapping layer and / or the distribution layer and / or the absorbent core. This may help reduce runoff.

[0354] The function of ADS50 is typically to rapidly capture liquid in an efficient manner and distribute it to an absorbent core. ADS may contain one, two, or more layers.

[0355] ADS does not necessarily have to contain superabsorbent polymers. Prior art discloses many types of capture-distribution systems; see, for example, International Publication No. 2000 / 59430, International Publication No. 95 / 10996, U.S. Patent No. 5700254, and International Publication No. 02 / 067809. However, superabsorbent polymer particles may also be included in the ADS.

[0356] The function of the distribution layer 54 is to spread the excreted fluid over a larger surface area within the article so that the absorption performance of the absorbent core can be utilized more efficiently. The distribution layer can be made of a relatively low-density nonwoven material, either synthetic or cellulose fiber-based. The distribution layer has a density of 30-400 g / m². 2 In particular, 80-300g / m 2 It may have an average basis weight.

[0357] The distribution layer 54 may contain, for example, at least 50% by weight, or 60% by weight, or 70% by weight, or 80% by weight, or 90% by weight of cross-linked cellulose fibers. The cross-linked cellulose fibers may be crimped, twisted, or curled, or a combination thereof including crimping, twisting, and curling. The cross-linked cellulose fibers impart high resilience and therefore high resistance to compression within the product packaging or under usage conditions, for example, less than the weight of an infant, to the first absorbent layer. This provides the core with relatively high void volume, permeability, and liquid absorption, thus reducing leakage and improving drying.

[0358] The distribution layer 54 containing cross-linked cellulose fibers may also contain other fibers, but this layer may contain at least 50% by weight, or 60% by weight, or 70% by weight, or 80% by weight, or 90% by weight, or even up to 100% by weight of cross-linked cellulose fibers, relative to the weight of the layer. An example of such a mixed layer of cross-linked cellulose fibers may contain 70% by weight of chemically cross-linked cellulose fibers, 10% by weight of polyester (PET) fibers, and 20% by weight of untreated pulp fibers. In another example, the cross-linked cellulose fiber layer may contain 70% by weight of chemically cross-linked cellulose fibers, 20% by weight of lyocell fibers, and 10% by weight of PET fibers. In yet another example, the layer may contain 68% by weight of chemically cross-linked cellulose fibers, 16% by weight of untreated pulp fibers, and 16% by weight of PET fibers.

[0359] The absorbent article 20 may further include a trapping layer 52 whose function is to quickly trap fluid away from the top sheet and provide the wearer with excellent drying properties. The trapping layer 52 is typically located directly below the top sheet and below the distribution layer. The trapping layer is typically a spunbond, meltblown, and further spunbonded layer, or alternatively, a nonwoven material, such as SMS or SMMS material, including a carded chemically bonded nonwoven fabric. The nonwoven material may specifically be latex-bonded. An exemplary top trapping layer 52 is disclosed in U.S. Patent No. 7,786,341. Carded resin-bonded nonwoven fabrics may be used, in particular when the fibers used are solid and round or round and hollow PET staple fibers (a 50 / 50 or 40 / 60 mixture of 6-denier and 9-denier fibers). An exemplary binder is butadiene / styrene latex.

[0360] The trapping layer 52 can be stabilized by a latex binder, such as a styrene-butadiene latex binder (SB latex). Methods for obtaining such a lattice structure are known, for example, in European Patent No. 149880 (Kwok) and U.S. Patent Application Publication No. 2003 / 0105190 (Diehl et al.). The binder may be present in the trapping layer 52 in amounts exceeding 12%, 14%, or 16% by weight, but may be present in amounts of 30% or less by weight, or 25% or less by weight, of the trapping layer. SB latex is available under the trade name GENFLO® 3160 (OMNOVA Solutions Inc.; (Akron, Ohio)).

[0361] In addition to the first trapping layer described above, further trapping layers may be used. For example, a tissue layer may be placed between the first trapping layer and the distribution layer. This tissue may have improved capillary distribution properties compared to the trapping layer described above. The tissue layer and the first trapping layer may be the same size or of different sizes; for example, the tissue layer may extend further behind the absorbent article than the first trapping layer. An example of a hydrophilic tissue is 13-15 g / m² of cellulose fiber from supplier Havix. 2 It has high wet strength.

[0362] The diaper may also include elastic leg cuffs 32 and / or barrier leg cuffs 34, in particular, within the leg opening area, which provides improved containment of liquid and other bodily waste. Typically, each leg cuff 32 and barrier cuff 34 will include one or more elastic straps 33 and 35, as exaggeratedly represented in Figures 12 and 13. Furthermore, the diaper 20 may include other structures such as rear ear sections 40, front ear sections 46 and / or barrier cuffs 34, which are attached to form a composite diaper structure. The diaper may further include a fastening system, such as an adhesive fastening system or a mechanical fastening system (e.g., a hook-and-loop fastener system), which may include a tape tab 42, such as an adhesive tape tab or a tape tab with a hook element, which works in cooperation with the landing area 44 (e.g., a nonwoven web providing a loop in a hook-and-loop fastener system). Furthermore, the diaper may include other elements such as a posterior elastic waist structure, an anterior elastic waist structure, side panels, or lotion application.

[0363] As shown in Figures 12 and 13, the diaper 20 can be conceptually divided into a first lumbar region 36, a second lumbar region 38 opposite the first lumbar region 36, and a crotch region 37 located between the first lumbar region 36 and the second lumbar region 38. The longitudinal centerline 80 is an imaginary line that bisects the diaper along its length. The transverse centerline 90 is an imaginary line perpendicular to the longitudinal line 80 in the plane of a completely flattened diaper and passing through the center of the diaper's length. The periphery of the diaper 20 is defined by its outer edge. The longitudinal edge of the diaper may extend approximately parallel to the longitudinal centerline 80 of the diaper 20, and the end edge extends approximately parallel to the transverse centerline 90 of the diaper 20 between the longitudinal edges.

[0364] Test method Contact angle test method: A rectangular test specimen measuring 1 cm x 2 cm is cut from the top sheet of a disposable absorbent product, taking care not to touch the surface of the specimen or disturb the structure of the material. The specimen has a length (2 cm) aligned with the longitudinal centerline of the article. The specimen is gently handled from the edge using forceps and mounted flat on the SEM specimen holder with the skin-facing side facing up using double-sided tape. Fine mist droplets of water, generated using a small household airbrush device, are sprayed onto the specimen. The water used to generate the droplets is distilled deionized water with a resistivity of at least 18 MΩ-cm. The airbrush is adjusted so that each droplet has a volume of approximately 2 pL. Approximately 0.5 mg of water droplets are evenly and gently applied to the specimen. Immediately after application of the water droplets, the mounted specimen is immersed in liquid nitrogen to freeze it. After freezing, the sample is transferred to a Cryo-SEM prep chamber at -150°C, coated with Au / Pd, and then transferred to a Cryo-SEM chamber at -150°C. High-resolution images of droplets on the fibers are obtained using a Hitachi S-4700 Cry-SEM or equivalent instrument. Droplets are selected randomly, but are suitable for imaging only if they are oriented in the microscope so that the projection of the droplet extending from the fiber surface is nearly maximized. The contact angle between the droplet and the fiber is directly determined from the acquired image, as shown by line 3700 in Figure 17.

[0365] Such a method is performed on a land region of a first surface of a first layer (or on the first surface of an optional second layer) to measure the contact angle of the first surface land region. Similarly, the method may be performed on a land region of a second surface of a first layer to measure the contact angle of the second surface land region. Ten separate droplets located on an intermediate land region between two adjacent holes are imaged, and 20 contact angle measurements are performed from them (one for each side of each imaged droplet). The arithmetic mean of these 20 contact angle measurements is calculated and reported as the first surface land region contact angle or the second surface land region contact angle, respectively.

[0366] This method is also performed on holes to measure the hole contact angle. Ten separate droplets located near the top of three separate holes and ten separate droplets located near the bottom of the same three separate holes are imaged, and 40 contact angle measurements are taken from them (one for each side of each imaged droplet). The arithmetic mean of these 40 contact angle measurements is calculated and reported as the hole contact angle.

[0367] Test methods for measuring percentage effective area, hole dimensions, and inter-hole distance: Effective hole dimensions, percentage effective area, and inter-hole distance measurements are obtained from hole specimen images acquired using a flatbed scanner. The scanner is capable of scanning in reflective mode with a resolution of 6400 dpi and 8-bit grayscale (a suitable scanner is the Epson Perfection V750 Pro from Epson America Inc. (Long Beach, CA) or its equivalent). The scanner is paired with a computer running an image analysis program (a suitable program is ImageJ v.1.47 from the National Institute of Health (USA) or its equivalent). The specimen images are distance-calibrated against acquired NIST-certified ruler images. The hole specimens are backed with black glass tiles (P / N 11-0050-30, or equivalent, available from HunterLab, Reston, VA) before image acquisition. The resulting grayscale images are then converted to binary images via threshold values, allowing separation of the hole regions from the specimen material regions, and these regions are analyzed using the image analysis program. All tests are conducted in a humidity-controlled room maintained at approximately 23±2°C and 50±2% relative humidity.

[0368] Sample preparation: To obtain test specimens, the absorbent article is taped to a rigid, flat surface of the planar configuration. Any elasticity of the legs present may be cut to facilitate the flat placement of the article. The outer boundary of the area located above the absorbent core of the article is identified and marked on the perforated layer. The perforated layer specimen is removed from the underlying layer of the article by cutting around the outer periphery of the article using a razor blade. The perforated layer specimen is carefully removed so as to maintain longitudinal and transverse elongation to avoid distortion of the holes. If necessary, the specimen may be removed from the underlying layer using a low-temperature spray (Cyto-Freeze (Control Company (Houston TX), or equivalent, etc.)). Five duplicate test specimens obtained from five substantially similar articles are prepared for analysis. The raw materials of the perforated substrate are prepared for testing by stretching or activating them under the same processing conditions and to the same degree as when used on the absorbent article. The samples are conditioned for 2 hours at approximately 23°C ± 2°C and approximately 50% ± 2% relative humidity before testing.

[0369] Image acquisition: The ruler is placed on the scanner bed so as to be oriented parallel to the side of the scanner glass. The image of the ruler (calibration image) is acquired in reflective mode at a resolution of 6400 dpi (approximately 252 pixels / mm) and 8-bit grayscale. The calibration image is saved as an uncompressed TIFF format file. After acquiring the calibration image, the ruler is removed from the scanner glass and all test specimens are scanned under the same scanning conditions. The perforated test specimen is placed flat in the center of the scanner bed with the outward-facing surface of the specimen facing the scanner glass surface. The corners and edges of the test specimen are fixed so as to restore their original longitudinal and transverse stretches to those of the article before removal. The test specimen is oriented so that the mechanical direction (MD) and transverse direction (CD) of the perforated test specimen layer are parallel and perpendicular to the side of the scanner glass surface, and the resulting test specimen image has an MD that runs vertically from top to bottom. A black glass tile is placed on top of the specimen, the scanner cover is closed, and a scan image of the entire specimen is acquired. The image is saved as an uncompressed TIFF file. The remaining four duplicate specimens are scanned and saved in the same format. Before analysis, all specimen images are cropped to the largest rectangular field of view contained within the perforated area located above the absorbent core of the article.

[0370] Percentage effective pore area calculation: The calibration image file is opened within the image analysis program, and linear distance calibration is performed using the captured ruler. This distance calibration scale is applied to all subsequent specimen images before analysis. The specimen images are located within the image analysis program, and the distance scale is set using the distance calibration. Next, the 8-bit grayscale image is converted to a binary image (using "zero" or "black" corresponding to the hole area) by the following means: a histogram of gradation (GL) values ​​(ranging from 0 to 255, with each bin representing the trend P for each gradation i). i If (including) has exactly two local maximums, the threshold grayscale value t is P t-1 >P t and P t ≤P t+1It is defined as the value that is P. If the histogram has more than two local maxima, the histogram is iteratively smoothed using a windowed arithmetic mean of size 3, and this smoothing is iteratively performed until there are exactly two local maxima. The threshold value t is P t-1 >P t and P t ≤P t+1 This is defined as a value that is . This procedure identifies the minimum population tonal (GL) value located between the dark pixel peak of the aperture hole and the brighter image peak of the specimen material. If the histogram contains either zero or one local maximum, the method cannot proceed further and the output parameter is undefined.

[0371] Each separate pore region is analyzed using an image analysis program. All individual pore areas, including partial pores along the edges of the image, are 0.01 mm². 2 Measured and recorded down to the unit. 0.3mm 2 Holes with an area less than 100% are defined as "invalid" and discarded. The area of ​​the remaining holes, including complete and partial holes, the so-called "effective" holes, is summed up. This sum is then divided by the total area included in the image. This value is multiplied by 100% and reported as the effective area to the nearest 0.01%.

[0372] The remaining four specimen images are analyzed in the same manner. For the five replicated specimens, the average percentage effective area value is calculated and reported to the nearest 0.01%.

[0373] Effective hole dimension measurement: The calibration image file (including the ruler) is opened within the image analysis program. The resolution of the original image is resized to 6400 dpi to 640 dpi (approximately 25.2 pixels / mm) using bicubic interpolation. Linear distance calibration is performed using the captured ruler. This distance calibration scale is applied to all subsequent specimen images before analysis. One specimen image is selected and opened within the image analysis program. The resolution of the original image is resized to 6400 dpi to 640 dpi (approximately 25.2 pixels / mm) using bicubic interpolation, and the distance scale is set according to the linear distance calibration established using the calibration image. Next, the 8-bit grayscale image is converted to a binary image (using "zero" or "black" corresponding to the hole area) by the following means: a histogram of gradation (GL) values ​​(ranging from 0 to 255, with one bin representing the trend P for each gradation i) is created. i If (including) has exactly two local maximums, the threshold grayscale value t is P t-1 >P t and P t ≤P t+1 It is defined as the value that is P. If the histogram has more than two local maxima, the histogram is iteratively smoothed using a windowed arithmetic mean of size 3, and this smoothing is iteratively performed until there are exactly two local maxima. The threshold value t is P t-1 >P t and P t ≤P t+1This is defined as a value that is . This procedure identifies the minimum population tonal (GL) value located between the dark pixel peak of the opening hole and the brighter pixel peak of the specimen material. If the histogram contains either zero or one local maximum, the method cannot proceed further and the output parameter is undefined. Next, two morphological operations are performed on the binary image. First, closing (an expansion process that converts any white background pixels in contact with black hole region pixels into black hole region pixels, thereby adding a layer of pixels around the outer edge of the hole region, followed by a contraction process that removes any black hole region pixels in contact with white background pixels, thereby removing a layer of pixels around the outer edge of the hole region, repeats = 1, number of pixels = 1) is performed to remove scattered fibers within the opening hole. Next, opening (a contraction process, followed by an expansion process, repeats = 1, number of pixels = 1) is performed to remove isolated black pixels. The edges of the image are padded during the contraction process to ensure that the black boundary pixels are maintained during processing. Finally, all remaining voids enclosed within the black hole region are filled.

[0374] Each separate pore region is analyzed using image analysis software. Any partial pores along the edges of the image are excluded so that only complete pores are analyzed. The individual pore area, perimeter, ferret diameter (pore length), and minimum ferret diameter (pore width) are all measured and recorded, along with their corresponding orientation angles from 0 to 180 degrees. 2 The outer circumference of the hole and the diameter (length and width) are recorded to the nearest 0.01 mm, and the angle is recorded to the nearest 0.01 degree. 0.3 mm 2 Holes with an area less than 1 cm² are all discarded as "invalid". The number of remaining "valid" holes is recorded and divided by the area of ​​the image. This quotient is the pore density value, calculated per 1 cm². 2The data is recorded down to the unit of 0.1 holes per specimen. The orientation angle of holes aligned with the MD (perpendicular in the image) is defined as 90 degrees. Holes with a positive slope increasing from left to right have angles between 0 and 90 degrees. Holes with a negative slope decreasing from left to right have angles between 90 and 180 degrees. The angle of each hole is used to calculate the absolute hole angle by subtracting 90 degrees from the original orientation angle and taking its absolute value. In addition to these measurements, the aspect ratio, defined for each hole as the quotient obtained by dividing its length by its width, is recorded. This analysis is repeated for each of the remaining images of the four replicated specimens. The statistical mean and standard deviation for each of the effective hole dimensions (area, perimeter, length, width, and angle), absolute hole angle, and aspect ratio measurements are calculated and reported using all the hole values ​​recorded from all specimens. The percentage relative standard deviation (RSD) for each of the effective hole dimensions, absolute hole angles, and aspect ratio measurements is calculated and reported by dividing the standard deviation by the mean and multiplying by 100%.

[0375] Measurement of the distance between holes The mean, standard deviation, median, and maximum inter-hole distances are measured by further analyzing the binary images of each specimen analyzed for hole dimension measurement. For each image, a Voronoi operation is performed on the resized and spatially calibrated binary image (as described above). The Voronoi operation generates an image bounded by lines of pixels where a region or "cell" is at a distance equal to the boundary lines of the two nearest pattern holes, with the pixel values ​​of these boundaries output from the Euclidean distance map (EDM) of the binary image, where all other pixel values ​​are zero. (The EDM is a transformed image in which each inter-hole pixel in the binary image is replaced with a value equal to the distance of the pixel from the nearest pattern hole.) A statistical analysis is performed on the non-zero distance values ​​(i.e., Euclidean distance values ​​along the boundaries) present in the Voronoi-transformed image. The resulting mean, standard deviation, median, and maximum inter-hole distances are calculated for the image and then multiplied by a multiple of 2 to reflect the perfect distance between hole features. These statistical indicators are reported to the nearest 0.01 mm. This procedure is repeated for all specimen images. The percentage relative standard deviation (RSD) of the hole distance is calculated by dividing the standard deviation by the mean and multiplying by 100%.

[0376] Conditioning-based contact angle test method: The top sheet specimen is removed from the absorbent article, centered on the intersection of the longitudinal and transverse centerlines of the absorbent article. To remove the top sheet from the absorbent article, a razor blade is used to cut the top sheet from the lower layer of the absorbent article around the outer perimeter of a 10±1cm × 10±1cm area. If the top sheet is not large enough to allow a 10±1cm × 10±1cm area to be cut from the intersection of the longitudinal and transverse centerlines, the largest square of the top sheet that can be extracted is cut and used thereafter as the top sheet specimen. The specimen is carefully removed so as to maintain its longitudinal and transverse elongation. If necessary, a low-temperature spray (such as Cyto-Freeze (Control Company, Houston TX)) can be used to remove the top sheet specimen from the lower layer.

[0377] The solution ("conditioning solution") is prepared using 0.9 wt% NaCl and 0.3 wt% sodium cholate by using distilled water, NaCl of over 99% purity, and sodium cholate of over 96% purity. The conditioning solution is heated to 40 ± 2°C and maintained at this temperature throughout the entire sample preparation. 100 (+ / - 10) mL of the temperature-maintained conditioning solution is filled into a glass container with a diameter of 150-180 mm. The test specimen is placed in the glass container containing the conditioning solution by keeping the test specimen submerged below the surface of the solution, and the glass container is placed in an artificial climate chamber at 40 (+ / - 2)°C for 30 ± 2 minutes.

[0378] The specimen is then removed from the solution using clean metal tweezers and placed on blotting paper (larger than the specimen). When the blotting paper becomes partially wet, new blotting paper is used. This is repeated until no further moisture is transferred to the blotting paper. The specimen is then transferred to a dry, clean glass container with a diameter of 150-180 mm, which is placed in an artificial climate chamber at 40°C for 30°C. The specimen is then cooled to room temperature. Rectangular specimens are cut from the conditioned specimen according to the contact angle method, measuring 1 cm × 2 cm. The first surface land area contact angle of the conditioned specimen, measured according to the contact angle test method described above, is reported as the first surface land area post-conditioning contact angle. Similarly, the second surface land area contact angle of the conditioned specimen, measured according to the contact angle test method described above, is reported as the second surface land area post-conditioning contact angle.

[0379] Leakage test method: The discharge volume is measured according to the basic method for testing hydrophilic nonwoven fabrics, WSP80.9(05), the standard test method for nonwoven fabric discharge volume. The inclination angle is set to 25°+ / -1°. A total mass of 25±0.5g of test solution is used.

[0380] The top sheet sample is removed from the absorbent material around the intersection of its longitudinal and transverse centerlines. To remove the top sheet from the absorbent material, a razor blade is used to cut the top sheet from the underlying layer of the absorbent material around the outer periphery of a 100 mm × 280 mm area. The specimen is carefully removed so as to maintain its longitudinal and transverse elongation. If necessary, a low-temperature spray (such as Cyto-Freeze (Control Company, Houston TX)) can be used to remove the top sheet specimen from the underlying layer. The 100 mm wide top sheet layer is centered on top of two 140 mm wide reference filter paper layers.

[0381] If the dimensions of the absorbent material do not allow for the removal of a 100mm x 280mm area, the largest possible rectangular top sheet area will be removed from the absorbent material using the procedure described above. Multiple test specimens will be taken from multiple absorbent materials and connected to each other by a 5mm wide overlap on each adjacent side between two separate test specimens. Double-sided tape adhesive will be placed within the 5mm wide overlapping area between the two layers that are stitched together. This procedure will allow for the creation of a 100mm x 280mm area to be used according to the basic method for testing hydrophilic nonwoven fabrics in the WSP80.9 procedure. For the test, the tube supplying the test fluid will be placed between any overlapping areas in the mechanical or transverse direction.

[0382] Capillary discharge test method The capillary discharge test method is used to determine the average amount of fluid (g / g) held by three test specimens at a differential pressure of 300 mmH2O. This method involves the use of a steppedly controlled differential pressure and the measurement of the associated fluid movement in and out of the porous test specimen. The amount of fluid (g / g) held by each test specimen is measured during the first discharge cycle at a differential pressure of 300 mmH2O, and the average value obtained from three similar test specimens is reported as the parameter CDP300.

[0383] Principles of the method For a uniform cylindrical pore, the pore radius is related to the differential pressure required to fill or empty the pore, according to the equation: differential pressure = (2γcosΘ) / r. In the formula, γ = liquid surface tension, Θ = contact angle, and r = pore radius.

[0384] Pores contained in natural and manufactured porous materials are often considered in terms of voids, holes, or conduits, and these pores are generally not perfectly cylindrical or uniform. Nevertheless, the distribution of effective pore radius in porous materials can be characterized by relating the differential pressure to the effective pore radius and monitoring the movement of liquid in and out of the material as a function of the differential pressure using the equations described above. (This general methodology may not produce results that precisely match those obtained by measuring void dimensions using other methods such as microscopy, because non-uniform pores are approximated uniformly by the use of the effective pore radius.)

[0385] The capillary discharge test method is implemented using the apparatus and techniques described in "Liquid Porosimetry: New Methodology and Applications" by B. Miller and I. Tyomkin, published in The Journal of Colloid and Interface Science (1994), volume 162, pages 163-170, which is incorporated herein by reference and uses the principle described above. This method relies on measuring the increment of liquid volume entering and leaving the porous material as the air pressure difference between the ambient ("lab") air pressure and the slightly elevated air pressure (positive differential pressure) surrounding the specimen in the sample chamber changes. The specimen is introduced into the sample chamber for drying, and the sample chamber is controlled with a sufficient positive differential pressure (relative to the laboratory) to prevent fluid from being taken into the specimen after the fluid bridge is opened. After the fluid bridge is opened, the air pressure difference is gradually reduced to 0, in which subgroups of pores capture the liquid according to their effective pore radius. After reaching the minimum differential pressure where the mass of fluid in the specimen is maximum, the differential pressure is again gradually increased toward the starting pressure, and the liquid is discharged from the specimen. During this latter discharge sequence (from the minimum differential pressure, or the maximum corresponding effective pore radius, to the maximum differential pressure, or the minimum corresponding effective pore radius), this method determines the fluid retention rate (g / g) by the specimen at each differential pressure. After correcting for any fluid movement for each specific pressure step measured on the chamber during the empty state, the fluid retention rate (g / g) by the specimen at each pressure step is determined by dividing the equilibrium amount (g) of retained liquid associated with this particular step by the dry weight (g) of the specimen.

[0386] Sample conditioning and specimen preparation The top sheet specimen is removed from the absorbent article, centered on the intersection of the longitudinal and transverse centerlines of the absorbent article. To remove the top sheet from the absorbent article, a razor blade is used to cut the top sheet from the lower layer of the absorbent article around the outer periphery of an area of ​​7±1cm × 7±1cm. (If the top sheet is not large enough to allow a 7±1cm × 7±1cm area to be cut from the intersection of the longitudinal and transverse centerlines, the largest square of the top sheet that can be extracted is cut and used thereafter as the top sheet specimen). The specimen is carefully removed so as to maintain its longitudinal and transverse elongation. If the top sheet is made of two layers, the first layer, containing at least 15% by weight of natural fibers relative to the total weight of the first layer, is separated and used for measurement in the capillary discharge test method. If necessary, a low-temperature spray (such as Cyto-Freeze (Control Company, Houston TX)) can be used to remove the top sheet specimen from the lower layer. A circular sample with a diameter of 50 mm is obtained from a top sheet test piece taken from an absorbent article.

[0387] The capillary discharge test method is performed on samples conditioned in a room at a temperature of 23°C ± 2.0°C and a relative humidity of 50% ± 5%, and all tests are performed under the same environmental conditions and in such a conditioned room. Damaged products or samples with defects such as wrinkles, tears, or holes are not tested. Samples prepared as described herein are considered dry samples for the purposes of this invention. Three test pieces are measured on any given material under test, and the results of these three duplicates are averaged to obtain the final reported value. Each of the three duplicate test pieces has a diameter of 50 mm.

[0388] Device Appropriate apparatus for this method is described in "Liquid Porosimetry: New Methodology and Applications" by B. Miller and I. Tyomkin, published in The Journal of Colloid and Interface Science (1994), volume 162, pages 163-170. Furthermore, any pressure control scheme capable of controlling the sample chamber pressure differential of 0 mmH2O to 1200 mmH2O may be used instead of the pressure control subsystem described in this reference. An example of a suitable overall instrumentation and software is the TRI / Autoporosimeter (Textile Research Institute (TRI) / Princeton Inc. of Princeton, NJ, USA). The TRI / Autoporosimeter is an automated computer-controlled instrument for measuring the pore volume distribution of porous materials (e.g., pore volumes of different sizes within the effective pore radius range of 1 to 1000 μm). Computer programs such as Automated Instrument Software Releases 2000.1 or 2003.1 / 2005.1 or 2006.2, or Data Treatment Software Release 2000.1 (available from TRI Princeton Inc.), and spreadsheet programs may be used to capture and analyze the measured data.

[0389] Method and Procedure The wetting liquid used is a degassed 0.9% NaCl solution. The liquid density is 1.01 g / cm³. 3The surface tension γ is set to 72.3 ± 1 mN / m, and the contact angle cosΘ = 0.37. A 90 mm diameter mixed cellulose-ester filter membrane with a characteristic pore size of 1.2 μm (e.g., Millipore Corporation of Bedford, MA, Catalogue #RAWP09025) is attached to the porous frit of the sample chamber (a 90 mm diameter, 6.4 mm thick Monel plate or equivalent made by Mott Corp., Farmington, CT).

[0390] Those skilled in the art will know that degassing of the test fluid and the frit / membrane / tube system is important to ensure that the system does not contain air bubbles.

[0391] A metal weight of 414g is placed on top of the sample, applying a constant restraining pressure of 2.068kPa during the measurement.

[0392] The differential pressure sequence performed during the test is 800, 400, 380, 360, 340, 320, 300, 280, 265, 250, 235, 220, 205, 190, 175, 160, 145, 130, 115, 100, 90, 80, 70, 60, 55, 50, 45, 40, 35, 30, 25 mmH2O. The values ​​are 20, 15, 10, 5, 0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 70, 80, 90, 100, 115, 130, 145, 160, 175, 190, 205, 220, 235, 250, 265, 280, 300, 320, 340, 360, 380, 400, and 800.

[0393] The criterion for moving from one pressure stage to the next is when the fluid intake / exhaustion from the test specimen is measured to be less than 10 mg / min for 15 seconds.

[0394] A separate “blank” measurement is performed in accordance with this method procedure on an empty sample chamber in which no specimen or weight is present on the membrane / frit assembly. Any fluid movement observed is recorded at each pressure stage (g). The fluid retention rate data of the specimen is corrected for any fluid movement associated with the empty sample chamber by subtracting the fluid retention value of this “blank” measurement from the corresponding value of the specimen measurement.

[0395] Determination of capillary discharge parameters As described above, for each of the three specimens, the capillary fluid (g) held by each specimen during its first discharge cycle at a differential pressure of 300 mmH2O is corrected for any effects of an empty chamber, and then divided by the dry mass of the specimen to obtain the discharged capillary fluid normalized by the dry sample mass in units of g / g. The arithmetic mean of the three normalized capillary fluid values ​​discharged from the three samples is reported as the g / g parameter CDP300 (discharge intake at 30 cm water column). [Examples]

[0396] The following are non-limiting examples of the top sheet of the present invention and comparative examples. These examples are provided for illustrative purposes only and should not be construed as limiting the present invention. Many modifications are possible without departing from the spirit and scope of the invention, and this will be understood by those skilled in the art.

[0397] Sample preparation: All of the following examples are top sheets comprising two layers, a first layer and a second layer, bonded together using a hydrophobic hot-melt adhesive applied to the second layer. The first layer is a three-dimensional layer, while the second layer is flat. The pores of the first layer are aligned with the pores of the second layer. The top sheets of each example are formed according to the process described above (see Figures 7-11). The hydrophobic surfactant is the same in all examples using a hydrophobic surfactant.

[0398] Example 1 is a top sheet comprising a first layer which is 100% cotton spunlace nonwoven fabric and a second layer which is SMS nonwoven fabric (spunbond-meltblown-spunbond). The first layer is treated with a hydrophobic surfactant via an immersion process. The second layer is hydrophilic. The basis weight of the first layer is 30 g / m². 2 The basis weight of the second layer is 8 g / m². 2 The basis weight of the hot melt adhesive applied to the second layer is 1 g / m². 2 That is the case.

[0399] Example 2 is a top sheet comprising a first layer which is 100% cotton spunlace nonwoven fabric and a second layer which is SMS nonwoven fabric (spunbond-meltblown-spunbond). The first layer is treated with a hydrophobic surfactant via an immersion process. The second layer is hydrophilic. The basis weight of the first layer is 30 g / m². 2 The basis weight of the second layer is 8 g / m². 2 The basis weight of the hot melt adhesive applied to the second layer is 2.5 g / m². 2 The second layer is applied by spraying at a rate of 2.7 g / m². 2 The first layer is treated with a hydrophilic surfactant, and then the second layer is dried. This makes the pores more hydrophilic.

[0400] Example 3 is a top sheet comprising a first layer which is a 100% cotton spunlace nonwoven fabric and a second layer which is a resin-bonded carded nonwoven fabric having 6 and 9 denier PET fibers. The first layer is treated with a hydrophobic surfactant via an immersion process. The second layer is hydrophilic. The basis weight of the first layer is 30 g / m². 2 The basis weight of the second layer is 33 g / m². 2 The basis weight of the hot melt adhesive applied to the second layer is 2.5 g / m². 2 The second layer is applied by spraying at 5.4 g / m². 2 The first layer is treated with a hydrophilic surfactant, and then the second layer is dried. This makes the pores more hydrophilic.

[0401] Example 4 is a top sheet comprising a first layer which is 100% cotton spunlace nonwoven fabric and a second layer which is SMS nonwoven fabric (spunbond-meltblown-spunbond). The basis weight of the first layer is 30 g / m². 2 The basis weight of the second layer is 8 g / m². 2 The basis weight of the hot melt adhesive applied to the second layer is 1 g / m². 2 The first layer is hydrophilic. The second layer is hydrophilic.

[0402] Example 5 is a top sheet comprising a first layer which is a 100% cotton spunlace nonwoven fabric and a second layer which is a carded air-through nonwoven fabric having 2 denier PE / PET two-component fibers. The first layer is treated with a hydrophobic surfactant via an immersion process. The second layer is hydrophilic. The basis weight of the first layer is 30 g / m². 2 The basis weight of the second layer is 50 g / m². 2 The basis weight of the hot melt adhesive applied to the second layer is 2 g / m². 2 The hydrophilic surfactant is attached to the pores via a pin process.

[0403] Example 6 is a top sheet comprising a first layer which is a 100% cotton spunlace nonwoven fabric and a second layer which is a card air-through nonwoven fabric made of CoPET fibers. The first layer is treated with a hydrophobic surfactant via an immersion process. The second layer is hydrophilic. The basis weight of the first layer is 35 g / m². 2 The basis weight of the second layer is 40 g / m². 2 The basis weight of the hot melt adhesive applied to the second layer is 2 g / m². 2 The hydrophilic surfactant is attached to the pores via a pin process.

[0404] Examples 1 and 4 are comparative examples. Examples 2, 3, 5, and 6 are top sheets according to the present invention.

[0405] result: The first surface land area contact angle on the land area, the hole contact angle on the hole, the outflow rate, CDP300, the width, length, perimeter, and area of ​​the hole are measured according to the corresponding test methods disclosed herein.

[0406] [Table 1] * Regarding this value, we deviated from the above test method and measured only 7 droplets. ** Regarding this value, we deviated from the above test method and measured only 5 droplets, of which 3 were measured at the top of the pore and 2 at the bottom. *** Regarding this value, we deviated from the above test method and measured only 5 droplets.

[0407] The contact angle between the first surface land region on the first surface land region of the first layer of the top sheet in Examples 1, 2, and 3, between most of the pores, is greater than 70° according to the contact angle test method. Therefore, the first layer of Examples 1, 2, and 3 is hydrophobic.

[0408] The pore contact angle over most of the pores in the top sheet of Example 1 is greater than 70° according to the contact angle test method. Most of the pores in the top sheet of Example 1 are hydrophobic.

[0409] The pore contact angles on most of the pores in the top sheets of Examples 2, 3, and 6 are less than 70° according to the contact angle test method. Most of the pores in the top sheets of Examples 2, 3, and 6 are hydrophilic.

[0410] Comparative Example 1 exhibits a higher leakage rate compared to Example 3 of the present invention. Therefore, when the top sheet of Example 1 is used in absorbent articles, there is a high risk of leakage.

[0411] The top sheet of Example 3 of the present invention has a leakage rate of less than 40% according to the leakage test method. Therefore, the top sheet of Example 3 of the present invention dries sufficiently and absorbs bodily fluids with almost no leakage. Consequently, when the top sheet is used in absorbent articles, the risk of bodily fluid leakage is reduced.

[0412] The top sheet of Example 3 of the present invention allows for better absorption of bodily fluids. The top sheet of Example 3 of the present invention reduces contact of liquid excretions with the wearer's skin. Therefore, the top sheet of Example 3 of the present invention is sufficiently dry when in contact with the wearer's skin.

[0413] Furthermore, the top sheets of Examples 3 and 2 of the present invention have a first surface land region post-conditioning contact angle of more than 50° on the land region of the first layer of the top sheet according to the post-conditioning contact angle test method. This makes it possible to have a top sheet that does not have wetting / re-wetting problems after a long period of wear.

[0414] Comparative Example 4 has a low outflow rate, but according to the capillary discharge test method, it has an outflow / uptake rate of more than 2 g / g in a 30 cm water column. Therefore, when the top sheet of Example 4 is used in an absorbent article, it does not allow the rapid passage of bodily fluids through its thickness toward the inner region of the absorbent article, resulting in a damp top sheet and a damper feel.

[0415] The top sheet of Example 5 of the present invention has a discharge rate of less than 40% according to the discharge test method and a discharge and uptake rate of less than 2 g / g in a 30 cm water column according to the capillary discharge test method. Therefore, the top sheet of Example 5 of the present invention dries sufficiently and absorbs bodily fluids with almost no discharge.

[0416] The top sheet of Example 6 of the present invention has a discharge rate of less than 40% according to the discharge test method and a discharge and uptake rate of less than 2 g / g in a 30 cm water column according to the capillary discharge test method. Therefore, the top sheet of Example 6 of the present invention dries sufficiently and absorbs bodily fluids with almost no discharge.

[0417] The dimensions and values ​​disclosed herein should not be understood as being strictly limited to the exact numerical values ​​listed. Instead, unless otherwise indicated, such dimensions are intended to mean both the listed value and the functionally equivalent range encompassing that value. For example, a dimension disclosed as "40 mm" is intended to mean "approximately 40 mm."

[0418] All documents referenced in this Application, including all cross-referenced or related patents or patent applications, and any patent applications or patents on which this Application claims priority or benefit thereof, are incorporated herein by reference in their entirety unless explicitly stated to exclude or limit them. No document reference shall be deemed prior art to any invention disclosed or claimed herein, nor shall it be deemed to teach, suggest or disclose all such inventions, either alone or in combination with any other reference(s). Furthermore, if any meaning or definition of a term in this Document conflicts with the meaning or definition of the same term in any document incorporated by reference, the meaning or definition given to that term in this Document shall apply.

[0419] While specific embodiments of the present invention have been illustrated and described, it will be apparent 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. Therefore, it is intended that all such changes and modifications within the scope of the invention be covered in the appended claims.

Claims

1. A top sheet (24) for use in an absorbent article, having at least a first layer (1) and a second layer (2), wherein the first layer has a first surface and an opposing second surface, and contains at least 15% by weight of natural fibers relative to the total weight of the first layer. The first layer (1) has a plurality of holes (5), and the first layer (1) includes land regions (8) between most of the holes (5), The first surface land region contact angle on the land region (8) of the first surface of the first layer (1) between the majority of the holes (5) is greater than 70° according to the contact angle test method. At least 50% of all pores in the first layer (1) are hydrophilic, The top sheet has an outflow of less than 40% according to the outflow test method. The second layer (2) has a first surface and an opposing second surface, and the second layer (2) includes a plurality of holes (5) and a land region (8) between the majority of the holes (5), and the first surface of the second layer (2) is in a relationship with the second surface of the first layer (1), so that the holes (5) of the second layer (2) are aligned with the holes (5) of the first layer (1), and the first layer (1) and the second layer (2) are in contact with and joined to each other within the land region (8) of the first and second layers (1, 2). The holes (5) in the first layer (1) penetrate at least partially through the holes (5) in the second layer (2), A top sheet (24) in which the contact angle of the second surface land region of the second layer (2) between the majority of the holes (5) is 70° or less according to the contact angle test method.

2. The top sheet (24) according to claim 1, wherein the plurality of pores are uniformly distributed within the first layer.

3. The top sheet (24) according to claim 1 or 2, wherein the contact angle of most of the holes is 70° or less according to the contact angle test method, and the contact angle of the first surface land area is at least 10° higher than the contact angle of the holes.

4. The top sheet (24) according to any one of claims 1 to 3, wherein the top sheet has an discharge / intake of less than 2 g / g at a 30 cm water column according to a capillary discharge test method.

5. The top sheet (24) according to any one of claims 1 to 4, wherein at least 75% of the pores of the first layer (1) are hydrophilic.

6. The top sheet (24) according to any one of claims 1 to 5, wherein the second layer (2) comprises synthetic fibers, natural fibers, and / or a combination thereof, and the synthetic fibers are single-component fibers, multi-component fibers, and a combination thereof.

7. The top sheet (24) according to any one of claims 1 to 6, wherein the second layer (2) has no protrusions, and the region of the second layer (2) that coincides with the protrusions (9) of the first layer is flat.

8. The top sheet (24) according to any one of claims 1 to 7, wherein the first layer (1) is attached to the second layer (2) within a bonding region by a hot melt adhesive, and the hot melt adhesive is hydrophilic.

9. The top sheet (24) according to any one of claims 1 to 8, wherein the first layer (1) includes a spunlace nonwoven fabric layer, and the spunlace nonwoven fabric layer contains natural fibers in an amount of at least 50% by weight relative to the total weight of the first layer (1).

10. The top sheet (24) according to any one of claims 1 to 9, wherein the natural fiber is a cotton fiber.

11. An absorbent article (20) having a longitudinal center line (80) and a transverse center line (90) perpendicular to the longitudinal center line, A top sheet (24) according to any one of claims 1 to 10, Back seat and, It includes an absorbent core positioned at least partially between the back sheet and the top sheet, An absorbent article (20) in which the first surface of the first layer (1) of the top sheet faces the wearer's skin during use of the article, and the second surface of the first layer (1) faces the absorbent core.

12. A top sheet (24) according to any one of claims 1 to 10, The first layer (1) contains at least 80% by weight of natural fibers relative to the total weight of the first layer, The first layer (1) comprises 5% to 40% by weight of hydrophilic fibers selected from the group consisting of synthetic fibers, natural fibers and / or combinations thereof, and 60% to 95% by weight of hydrophobic natural fibers relative to the total weight of the first layer (1). The top sheet (24) has an outflow rate of less than 40% according to the outflow test method.

Images