CN111107817A

CN111107817A - Absorbent article

Info

Publication number: CN111107817A
Application number: CN201880061846.2A
Authority: CN
Inventors: 高阪翔士
Original assignee: Unicharm Corp
Current assignee: Unicharm Corp
Priority date: 2017-11-17
Filing date: 2018-10-10
Publication date: 2020-05-05
Anticipated expiration: 2038-10-10
Also published as: CN111107817B; TWI782122B; JP6509306B1; TW201922299A; JP2019092597A; WO2019097907A1

Abstract

The invention provides an absorbent article which can exert good absorption performance even under the condition that urine is repeatedly supplied from a wearer in the absorbent article taking urine as a target. The surface sheet (2) of the urine absorbent article of the present invention has a concave portionConvex structure and having a thickness of 25g/m²～50g/m²In the uneven structure, ridges (21) and grooves (22) are alternately arranged along a second direction perpendicular to a first direction, the ridges projecting toward the skin-facing surface side in the thickness direction and extending in the first direction, the grooves being recessed toward the non-skin-facing surface side in the thickness direction and extending in the first direction parallel to the ridges (21), the surface sheet (2) has high-density portions having a relatively high fiber density in the grooves (22), and protein dispersing means for dispersing Tamm-Hofarll proteins contained in urine is provided on the surface on the skin-facing surface side.

Description

Absorbent article

Technical Field

The present invention relates to an absorbent article for urine such as a (light) incontinence pad and a disposable diaper.

Background

Conventionally, in absorbent articles such as (light) incontinence pads, disposable diapers, and sanitary napkins, the ability to quickly absorb excretory fluid such as urine and menstrual blood excreted from a wearer and to keep the excretory fluid from leaking to the outside has been required.

For example, patent document 1 discloses an absorbent article such as a sanitary napkin or a panty liner containing a water-soluble compound having 3 or more nitrogen atoms and 1 to 3 carbon atoms. In the absorbent article disclosed in patent document 1, the water-soluble compound modifies proteins contained in excretory fluids such as menstrual blood and leucorrhea (hereinafter referred to as "menstrual blood and the like") to lower the viscosity of the menstrual blood and the like, thereby allowing the menstrual blood and the like to be rapidly delivered into the absorbent body.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open No. 2014-100256

Disclosure of Invention

Problems to be solved by the invention

On the other hand, in an absorbent article for urine such as a (light) incontinence pad or a disposable diaper, when a wearer of an elderly person or the like repeatedly discharges urine, the absorption rate of the absorbent article gradually decreases, and the wearer may be given a feeling of wetness or urine may leak to the outside depending on the situation. As to the cause of such a decrease in absorption rate, various assumptions have been made so far (for example, solid components contained in urine (for example, ammonium magnesium phosphate stones, calcium oxalate crystals, etc.) block the surface sheet of the absorbent article), but the present inventors have made intensive studies on the cause of such a decrease in absorption rate, and have found that the decrease in absorption rate is caused by blocking the surface sheet with a specific protein such as Tamm-Horsfall protein (THP) contained in the urine of the wearer.

In view of such findings, it is expected that the above-described decrease in absorption rate can be avoided by applying the water-soluble compound of patent document 1 to an absorbent article intended for urine, but in reality, even if the water-soluble compound of patent document 1 is applied to an absorbent article intended for urine, urine has a low viscosity unlike menstrual blood or the like and easily reaches the absorbent body, and therefore, the protein component modified by the water-soluble compound reaches the absorbent body together with urine and adheres to the surface of an absorbent material (for example, Super Absorbent Polymer (SAP) or the like) in the absorbent body, and as a result, there is a possibility that the absorption performance of the absorbent body and further the absorption performance of the absorbent article are decreased.

Therefore, an object of the present invention is to provide an absorbent article that can exhibit good absorption performance even when urine is repeatedly supplied from a wearer in an absorbent article for urine.

Means for solving the problems

An absorbent article according to one aspect of the present invention (claim 1) includes a surface sheet and an absorbent body, the surface sheet and the absorbent body being arranged to overlap each other in a thickness direction, the absorbent article being intended for urine, wherein the surface sheet has an uneven structure and has a thickness of 25g/m²～50g/m²In the uneven structure, a ridge portion protruding toward a skin-facing surface side of the absorbent article in the thickness direction and extending in a first direction and a groove portion protruding toward the skin-facing surface side of the absorbent article in the thickness direction are alternately arranged along a second direction orthogonal to the first directionThe non-skin-facing surface side of the absorbent article is concave and extends in the first direction parallel to the ridges, and the top sheet has high-density portions with a relatively high fiber density in the grooves and protein dispersing means for dispersing Tamm-Horsfall proteins contained in urine on the surface of the skin-facing surface side.

The surface sheet of the absorbent article of this embodiment is formed of the specific nonwoven fabric having the above-described uneven structure, basis weight, and thickness, and urine supplied to the surface sheet can be made to permeate in the thickness direction of the surface sheet while diffusing along the groove portions. In this case, in the absorbent article of the present embodiment, the protein dispersing means for dispersing the Tamm-Horsfall protein (THP) contained in urine is provided on the surface of the skin-facing surface side of the topsheet, so that while THP, which is a cause of clogging of the topsheet (i.e., a cause of a decrease in absorption rate), is dispersed on the topsheet, THP, which is a cause of a decrease in absorption rate, can permeate in the thickness direction of the topsheet with the flow of urine, and the dispersed THP component can be dispersed in the thickness direction and in the in-plane direction of the topsheet, and can be retained at least in the high-density portion and can be easily retained in the topsheet.

Thus, the absorbent article of this aspect can hardly cause clogging due to THP in the topsheet (that is, hardly causes a decrease in the absorption rate of the topsheet), and can hardly cause such a case that the dispersed THP (dispersed component of THP) reaches the absorbent body disposed on the non-skin-facing surface side of the topsheet and adheres to the absorbent material in the absorbent body (that is, can hardly cause a decrease in the absorption performance of the absorbent body), so that it can exhibit good absorption performance as an absorbent article even when urine is repeatedly supplied from the wearer.

In another aspect (aspect 2) of the present invention, in the absorbent article according to aspect 1, the protein-dispersed unit is at least one member selected from the group consisting of a protein modifier, an anionic surfactant, a salt concentration adjuster, a protease, and a weakly basic agent.

The protein-dispersed unit of the absorbent article of the present embodiment is at least one component selected from the group consisting of a protein modifier, an anionic surfactant, a protease, and a weakly basic agent, and is a component capable of modifying or decomposing THP to reduce the THP into small pieces or to solubilize THP in water (i.e., soluble in urine) and is a component capable of being easily applied to a surface sheet, and therefore, THP contained in the urine of a wearer can be dispersed more efficiently and effectively.

In still another aspect (aspect 3) of the present invention, in the absorbent article according to aspect 2, the protein dispersing unit is the protein modifying agent, and the protein modifying agent is a chaotropic salt.

In the absorbent article of the present embodiment, the protein-dispersed units are chaotropic salts which have a strong effect of modifying THP and can modify THP so as to improve solubility in water without causing salting-out, and therefore, the above-described clogging of the surface sheet by THP can be more reliably and effectively prevented from occurring.

In still another aspect (aspect 4) of the present invention, in the absorbent article according to aspect 2, the protein dispersing unit is the anionic surfactant, and the anionic surfactant is sodium lauryl sulfate.

The protein dispersion unit of the absorbent article in this embodiment is Sodium Dodecyl Sulfate (SDS), which has a strong protein-modifying effect, can be solubilized even with a protein having strong hydrophobicity, which is insoluble in other methods, and can inactivate the function of the protein, so that the above-described clogging due to THP can be made more difficult to occur.

In still another aspect (aspect 5) of the present invention, in the absorbent article according to any one of aspects 1 to 4, the thickness of the ridge portions of the top sheet is 0.3mm to 1.5mm greater than the thickness of the groove portions, the ridge portions have a width of 2.0mm to 4.0mm, and the groove portions have a width of 0.5mm to 2.0 mm.

Since the ridges and grooves of the top sheet of the absorbent article of this embodiment have the above-described specific structure, the dispersed THP component in the ridges can be easily dropped into the grooves, and the ridges can be made less likely to collapse even if the top sheet is wetted with urine.

In this way, the absorbent article of this aspect can easily ensure a flow path for urine in the ridges of the top sheet even when urine is repeatedly supplied from the wearer, and therefore can exhibit more excellent absorption performance.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the absorbent article for urine of the present invention, even when urine is repeatedly supplied from a wearer, excellent absorption performance can be exhibited.

Drawings

Fig. 1 is a top view of a light incontinence pad 1 according to an embodiment of the present invention.

Fig. 2 is an end view of the light incontinence pad 1 in a section along the line II-II' in fig. 1.

Fig. 3 is an enlarged end view of a main part of the topsheet 2 of the mild incontinence pad 1.

Detailed Description

Hereinafter, preferred embodiments of the absorbent article of the present invention will be described in detail with reference to the accompanying drawings. In the present specification, unless otherwise specified, "an object placed on a horizontal plane in a state of being laid out in a thickness direction of an object (for example, an absorbent article, a topsheet, an absorbent body, or the like)" from an upper side in a vertical direction (a topsheet side in the case where the object is an absorbent article) "is simply referred to as" a top view ".

The various directions and the like used in the present specification are as follows unless otherwise specified.

In the present specification, "longitudinal direction" refers to a direction in which the length of an object (for example, an absorbent article, a topsheet, an absorbent body, or the like) that is longitudinally long in a plan view is long, "width direction" refers to a direction in which the length of an object that is longitudinally long in a plan view is short (short-side direction), "and" thickness direction "refers to a direction perpendicular to an object placed on a horizontal plane in an unfolded state, and these longitudinal direction, width direction, and thickness direction are orthogonal to each other. In the present specification, the "plane direction" refers to a direction in which a plane of a substantially sheet-like object (for example, an absorbent article, a topsheet (nonwoven fabric), or the like) extends (i.e., a horizontal plane direction) in a plan view, and the plane direction and the thickness direction are orthogonal to each other.

In the present specification, the term "in the longitudinal direction of a vertically long object" is used to refer to a longitudinal central axis C which is located at the center of the object in the longitudinal direction and extends in the width direction_WThe relatively close proximal side is referred to as "inner side in the longitudinal direction", and "in the longitudinal direction of the longitudinally long object, with respect to the longitudinal central axis C_WThe distal side that is relatively distant is referred to as "the longitudinal outer side". Similarly, the term "in the width direction of a vertically long object" is defined as a line that is parallel to a width direction central axis C that is located at the center of the object in the width direction and extends in the longitudinal direction_LThe relatively close proximal side is referred to as "inner side in the width direction", and "is relative to the width direction central axis C in the width direction of the longitudinally long object_LThe distal side that is relatively distant is referred to as "the widthwise outer side".

In the present specification, unless otherwise specified, in the thickness direction of the absorbent article, "the proximal side relatively close to the skin surface of the wearer when the absorbent article is worn" is referred to as "skin-facing surface side", and "the distal side relatively distant from the skin surface of the wearer when the absorbent article is worn" is referred to as "non-skin-facing surface side". Here, "wearing time" refers to a period (wearing period) during which the absorbent article is maintained from a time when the wearer wears the absorbent article (i.e., a time when the usable state is established).

In the present specification, the "surface on the skin-facing surface side" and the "surface on the non-skin-facing surface side" of the absorbent article and various members (e.g., the front sheet, the absorbent body, the back sheet, etc.) constituting the absorbent article may be simply referred to as "skin-facing surface" and "non-skin-facing surface", respectively.

Fig. 1 is a plan view of a light incontinence pad 1 according to an embodiment of the invention, and fig. 2 is an end view of the light incontinence pad 1 in a section along the line II-II' in fig. 1. In addition, fig. 3 is an enlarged end view of a main part of the topsheet 2 of the light incontinence pad 1.

As shown in fig. 1, the light incontinence pad 1 (an example of the "absorbent article" in the present invention) has a longitudinal direction L and a width direction W in a plan view, and has an oval outer shape in which both end portions in the longitudinal direction L protrude so as to draw a circular arc toward the outer side in the longitudinal direction L. In the present invention, the outer shape of the absorbent article is not limited to this form, and any longitudinally long shape (for example, a rectangle, an ellipse, an hourglass shape, or the like) according to various applications may be employed as long as the length in the longitudinal direction L is longer than the length in the width direction W.

As shown in fig. 1 to 3, the light incontinence pad 1 includes, in the thickness direction T: on the side T of the skin facing surface₁A liquid-permeable surface sheet 2 made of a nonwoven fabric having a specific uneven structure including ridges 21 and grooves 22, which will be described later; on the non-skin-facing side T₂The liquid-impermeable back sheet 3; and a non-skin-facing side T between the two sheets (i.e., in the thickness direction T)₂Superposed with the topsheet 2) liquid-absorbent and liquid-retentive absorbent body 4 serves as a main structural member.

As shown in fig. 1 and 2, the light incontinence pad 1 further includes: on the skin-facing surface side T of the front sheet 2₁A pair of liquid-

impermeable side sheets

5, 5 positioned at both ends in the width direction W and capable of functioning as a leakage-preventing wall portion; arranged on the non-skin-facing surface side T of the back sheet 3₂A garment-fixing adhesive part (not shown) for fixing the light incontinence pad 1 to a garment worn by a wearer, such as underwear; and a non-skin-facing surface side T arranged on the garment-fastening adhesive section₂A release sheet (not shown) for protecting the garment-fastening adhesive part before use is used as a structural member.

The light incontinence pad 1 is worn by peeling the release sheet, and the light incontinence pad 1 is disposed on the non-skin-facing surface side T₂The garment-fixing adhesive part of the surface of (2) is fixed to the inner surface of a garment worn by a wearer such as underwear, and is worn so that the surface sheet 2 faces the skin of the wearer. When urine is discharged from the wearer, the urine is supplied to the skin-facing surface side T of the topsheet 2 of the light incontinence pad 1₁The surface of (2) is spread in the planar direction and is directed to the non-skin-facing surface side T in the thickness direction T₂The liquid permeates through the absorbent body 4 and is absorbed and retained therein.

In the light incontinence pad 1 of the present embodiment, as shown in fig. 1 to 3, the top sheet 2 has an uneven structure and 25g/m²～50g/m²And a thickness of 0.7mm to 2.0mm, wherein the uneven structure is formed on the skin-facing surface side T in the thickness direction T₁A ridge portion 21 projecting and extending in the longitudinal direction L (an example of the "first direction" in the present invention), and a non-skin-facing surface side T in the thickness direction T₂The groove portions 22 that are recessed and extend in the longitudinal direction L in parallel with the raised portions 21 are alternately arranged in the width direction W (an example of the "second direction" in the present invention). The top sheet 2 has a high-density portion with a relatively high fiber density in the groove portion 22, and is on the skin-facing surface side T₁Has a protein dispersion unit for dispersing Tamm-Horsfall protein (THP) contained in the urine of the wearer.

In this way, the surface sheet 2 of the light incontinence pad 1 of the present embodiment is formed of the specific nonwoven fabric having the above-described uneven structure, basis weight, and thickness, and urine supplied to the surface sheet 2 can be spread in the longitudinal direction L along the groove portions 22 and can be directed to the non-skin-facing surface side T in the thickness direction T of the surface sheet 2₂And (4) infiltration. In this case, the light incontinence pad 1 is disposed on the skin-facing surface side T of the topsheet 2₁Has a protein dispersion means for dispersing THP contained in the urine of the wearer, and can cause the clogging of the topsheet 2The THP (i.e., a cause of the decrease in the absorption rate) is dispersed in the surface sheet 2, and while permeating in the thickness direction T of the surface sheet 2 with the flow of urine, the dispersed components of the THP can be dispersed in the thickness direction T and the plane direction in the surface sheet 2, and at least remain in the high-density portion, and thus easily remain in the surface sheet 2.

Thus, the light incontinence pad 1 of the present embodiment can prevent the surface sheet 2 from being clogged with THP (i.e., can prevent the absorption rate of the surface sheet 2 from being reduced), and can allow dispersed THP (dispersed components of THP) to reach the non-skin-facing surface side T disposed on the surface sheet 2₂The absorbent body 4 of (a) is less likely to be attached to the absorbent material in the absorbent body 4 (that is, the absorption performance of the absorbent body 4 can be less likely to be lowered), and therefore, even in the case of repeatedly supplying urine from the wearer, good absorption performance can be exhibited.

Hereinafter, various members constituting the absorbent article of the present invention will be described in more detail using the light incontinence pad 1 of the above embodiment.

[ surface sheet ]

In the light incontinence pad 1 of the above embodiment, as shown in fig. 1 and 2, the top sheet 2 is disposed at a position that can be brought into direct contact with the skin of the wearer (i.e., the skin-facing surface side T of the light incontinence pad 1), except for the portion overlapping the pair of

side sheets

5, 5 in the thickness direction T₁The position (b) of the absorbent article, and is composed of a liquid-permeable nonwoven fabric through which urine discharged from a wearer can pass.

As shown in fig. 1 and 2, the top sheet 2 is arranged on the non-skin-facing surface side T of the top sheet 2 in plan view₂The skin-facing surface side T of the absorbent body 4₁Extends in the longitudinal direction L and the width direction W so as to cover the entire surface, and has an oval outer shape in which both end portions in the longitudinal direction L protrude so as to draw a circular arc toward the outer side in the longitudinal direction L, similarly to the outer shape of the light incontinence pad 1. In the absorbent article of the present invention, the outer shape of the top sheet is not limited to this form, provided that the surface of the skin-facing side of the absorbent body is at least on the side facing the wearerThe area corresponding to the crotch portion is not exposed, and any shape and size according to various applications and the like can be adopted.

In the present invention, the nonwoven fabric usable as the top sheet is not particularly limited as long as it has various properties (for example, liquid permeability, skin touch, flexibility, strength, and the like) usable as the top sheet of the absorbent article, and for example, any nonwoven fabric such as a hot air nonwoven fabric, a spunbond nonwoven fabric, a point-bond nonwoven fabric, and the like can be used. The nonwoven fabric may be subjected to hydrophilization treatment.

The fibers constituting the nonwoven fabric are not particularly limited, and for example, resin fibers made of an olefin resin such as polyethylene or polypropylene, or a thermoplastic resin such as a polyester resin such as polyethylene terephthalate or polylactic acid may be used, and these resins may be used alone or in combination of two or more kinds.

Further, in the present invention, the nonwoven fabric usable as the surface sheet has a thickness of 25g/m²～50g/m²The weight per unit area and the thickness of 0.7mm to 2.0 mm. When the surface sheet is formed of a nonwoven fabric having such a weight per unit area and a thickness, the dispersed components of THP dispersed by the protein dispersing units can easily permeate in the thickness direction T of the surface sheet (nonwoven fabric) together with urine, and can be easily held between the structural fibers in the nonwoven fabric (in other words, the dispersed components of THP can be easily filtered out of urine).

In the present invention, the weight per unit area of the nonwoven fabric is preferably 28g/m²～48g/m²More preferably 30g/m²～45g/m²Within the range of (1). The thickness of the nonwoven fabric is preferably in the range of 0.7mm to 1.8mm, and more preferably in the range of 0.8mm to 1.6 mm. In the present specification, as shown in fig. 3, the thickness of the nonwoven fabric means that the nonwoven fabric (surface sheet) is placed so that the surface of the nonwoven fabric on the non-skin-facing surface side is the lower sideThe distance in the thickness direction between the top of the ridge portion having the highest height from the horizontal plane and the horizontal plane, i.e., the thickness d of the entire nonwoven fabric, when viewed in the horizontal plane.

The basis weight of the nonwoven fabric can be measured in accordance with JIS L1906, 5.2, and the thickness of the nonwoven fabric can be measured in a non-contact manner using a laser displacement meter (for example, a high-precision two-dimensional laser displacement meter LJ-G series (model: LJ-G030), manufactured by Keyence). The thickness of the nonwoven fabric was measured at 5 different portions of the measurement target (i.e., at the top of the raised strip), and the average value was used.

In the above embodiment, as shown in fig. 1 to 3, the top sheet 2 has a skin-facing surface side T in the thickness direction T₁Protrudes and is in a first direction D₁(in the present embodiment, the direction corresponding to the longitudinal direction L of the light incontinence pad 1) and the ridges 21 extending in the thickness direction T toward the non-skin-facing surface side T₂Recessed and parallel to the raised strips 21 in the first direction D₁The extending groove portion 22 extends along the first direction D₁Orthogonal second direction D₂(in the present embodiment, the direction corresponding to the width direction W of the light incontinence pad 1) alternately. When the surface sheet has such an uneven structure including the ridges and grooves, urine supplied to the surface sheet can gradually permeate toward the non-skin-facing surface in the thickness direction of the surface sheet while being diffused in the longitudinal direction along the grooves. In this case, since the surface of the skin-facing surface of the topsheet has a protein-dispersing unit for dispersing THP contained in urine, while THP causing clogging of the topsheet (i.e., causing a decrease in absorption rate) is dispersed in the topsheet in the in-plane direction, THP gradually permeates in the thickness direction of the topsheet with the flow of urine, and the dispersed THP component can be dispersed in the thickness direction and in the in-plane direction of the topsheet. This makes it possible to ensure a urine flow path more easily and to prevent clogging due to THP.

In the present invention, the direction in which the ridges and grooves of the top sheet extend (i.e., the first direction D)₁) The present invention is not limited to the above-described embodiments (i.e., the direction corresponding to the longitudinal direction of the absorbent article), and any direction such as a direction corresponding to the width direction of the absorbent article may be employed as long as the direction can diffuse urine supplied to the surface of the skin-facing surface side of the top sheet in the planar direction. In the above-described embodiment, as shown in fig. 1 and 2, the ridges and grooves of the top sheet are disposed on the entire top sheet (that is, the ridges and grooves extend from one end portion to the other end portion in the longitudinal direction and are alternately disposed from one end portion to the other end portion in the width direction). In this case, from the viewpoint of more favorably exhibiting the effects of the present invention, the ridges and grooves are preferably arranged at least in a region overlapping in the thickness direction with the absorbent body positioned on the non-skin-facing surface side of the top sheet (i.e., at least in a region covering the entire skin-facing surface of the absorbent body).

In the present specification, the ridges and grooves of the surface sheet may be divided as follows. That is, as shown in FIG. 3, the front sheet 2 is arranged on the non-skin-facing surface side T₂When the front surface of (2) is placed on a horizontal surface so as to be a lower side, a portion having the highest height from the horizontal surface is defined as a "top portion 21T" of the convex portion 21, a portion having the lowest height from the horizontal surface is defined as a "bottom portion 22B" of the groove portion 22, and a portion protruding upward is defined as the "convex portion 21" and a portion recessed downward is defined as the "groove portion 22" as compared with a virtual reference horizontal surface P extending at a position bisecting the thickness d of the entire front surface sheet (nonwoven fabric) (i.e., at positions separated by distances of d/2 from the top portion 21T and the bottom portion 22B in the thickness direction T).

The ridges and grooves may be formed on the surface sheet along the second direction D by a magnifying observation means such as a scanning electron microscope₂The cross section of (a) is observed under magnification and discriminated from the photograph or image thereof.

In the above embodiment, as shown in fig. 2 and 3, the top sheet 2 has the non-skin-facing surface side T₂Has a surface T facing the skin₁The convex portions 21 and the groove portions 22 have concave-convex structures corresponding to the concave portions and the convex portions, and the internal structure of the convex portions 21 is hollow. In the absorbent article of the present invention, the surface structure of the surface sheet on the non-skin-facing surface side is not limited to such a structure as long as the effects of the present invention are not impaired, and for example, any arbitrary structure such as a flat structure (that is, a structure in which the internal structure of the ridge portions is solid) without the above-described concave portions and convex portions may be provided, but from the viewpoints of liquid permeability (particularly, permeability of repeatedly supplied urine), cushioning properties, skin touch, and the like, the surface structure of the surface sheet on the non-skin-facing surface side is preferably provided with a concave-convex structure (that is, a structure in which the internal structure of the ridge portions is hollow) having concave portions and convex portions corresponding to the convex portions and groove portions on the skin-facing surface side as in the above-described embodiment.

In the above embodiment, the top sheet 2 has a high-density portion (not shown) having a relatively high fiber density in the groove portion 22. If the top sheet has such high-density portions in the groove portions, the dispersed THP components that have permeated in the thickness direction T in the top sheet (nonwoven fabric) together with urine pass through the structural fibers of the nonwoven fabric and are retained in the high-density portions of the groove portions, and therefore, the dispersed THP components can be easily retained in the top sheet. This makes it possible to prevent the dispersed THP component from reaching the absorbent body located on the non-skin-facing surface side of the topsheet and adhering to the absorbent material in the absorbent body (i.e., to prevent the absorption performance of the absorbent body from being reduced). Further, since such high-density portions are present in the groove portions, it is easy to ensure a flow path for urine in the ridge portions, and therefore, even in a case where urine is repeatedly supplied from a wearer, the liquid permeability of the top sheet can be favorably maintained.

Here, the judgment of the density (fiber density) of each part (ridge part, groove part, etc.) of the surface sheet (nonwoven fabric) can be made by visually observing each of the target parts (for example, 1mm × 1mm size) to which the density is compared, at a magnification of about 20 to 100 times by using a magnification observation means such as a scanning electron microscope, based on the number of fibers per unit area.

In the present invention, specific configurations of the ridges and grooves are not particularly limited as long as the effects of the present invention are not impaired, and for example, the height of the ridge (i.e., the distance in the thickness direction from the virtual reference horizontal plane P to the top) is in the range of 0.1mm to 3.0mm, the depth of the groove (i.e., the distance in the thickness direction from the virtual reference horizontal plane P to the bottom) is in the range of 0.1mm to 3.0mm, and the pitch of the plurality of ridges (i.e., the interval between the centers of the tops of two ridges adjacent in the second direction) is in the range of 1.0mm to 10.0 mm.

Further, the width of the ridge (i.e., the skin-facing surface side T of the ridge 21 as shown in FIG. 3)₁In a second direction D₂Upper longest length portion 21W in the second direction D₂Upper length) is, for example, in the range of 0.5mm to 5.0mm, and the width of the groove portion (that is, as shown in FIG. 3, the skin-facing surface side T of the groove portion 22₁In a second direction D₂Has the longest length of the portion 22W in the second direction D₂Upper length) is in the range of 0.5mm to 5.0mm, for example. The widths of the ridges and the grooves may be the same or different.

As described above, in the present invention, the structure of the ridges and grooves of the surface sheet is not particularly limited as long as the effect of the present invention is not hindered, and the thickness of the ridges (that is, the thickness T of the tops 21T of the ridges 21 in fig. 3) is preferably the same as the thickness of the surface sheet 2 shown in fig. 3₁) Is smaller than the thickness of the groove portion (i.e., the thickness t of the bottom portion 22B of the groove portion 22 in FIG. 3)₂) 0.3mm to 1.5mm larger, and the raised strip portions have a width of 2.0mm to 4.0mm, and the groove portions have a width of 0.5mm to 2.0 mm. When the surface sheet has such a specific structure, the dispersed THP component can be easily dropped into the groove portions in the ridges, and the ridges can be made less likely to collapse even if the surface sheet is wetted with urine. Thereby, even when urine is discharged from the wearerEven in such a case of repeated supply, the flow path of urine can be easily secured in the ridges of the top sheet (that is, the liquid permeability of the top sheet can be easily maintained), and therefore, more excellent absorption performance can be exhibited as an absorbent article.

The pitch and width of the ridges and grooves may be measured from a plane image or a cross-sectional image of the nonwoven fabric under a non-pressurized state by observing the nonwoven fabric under magnification using a magnification unit such as a scanning electron microscope. The heights, depths, thicknesses, and the like of the ridges and grooves may be measured by observing the pitches and widths under magnification using a magnifying observation means such as a scanning electron microscope, or may be measured in a non-contact manner using a laser displacement meter.

The method for forming the above-described uneven structure on the surface sheet (nonwoven fabric) is not particularly limited, and any shaping method such as a method of continuously blowing a gas (e.g., air) onto one surface of the web before the nonwoven fabric is formed (hereinafter, sometimes referred to as "gas blowing method"), a method of gear machining (hereinafter, sometimes referred to as "gear machining method"), and a method of vacuum forming or compression forming may be employed. Among them, from the viewpoint of shaping the above-mentioned uneven structure and easily forming a high-density portion having a high fiber density in the groove portion, a gas blowing method and a gear processing method are preferable.

The top sheet may be joined to the non-skin-facing surface of the pair of side sheets, may be joined to the skin-facing surface or the non-skin-facing surface of the absorbent body, may be joined to the skin-facing surface of the back sheet, or may be joined to both of them. The joining method is not particularly limited, and any joining method such as a hot-melt adhesive or thermal welding may be used.

[ protein Dispersion Unit ]

Next, a protein dispersing unit that can be used in the absorbent article of the present invention will be described.

In the present invention, the protein dispersing means is applied to the surface of the skin-facing surface side of the surface sheet, and has an action of dispersing a specific protein such as Tamm-Horsfall protein (THP) contained in urine of a wearer by contacting the urine with the urine supplied to the surface of the skin-facing surface side of the surface sheet. In the present specification, "dispersing a protein" means that the protein is broken into small pieces or is dispersed by dissolving in water (i.e., soluble in urine).

In the present invention, the protein-dispersed unit is not particularly limited as long as it can disperse THP contained in the urine of the wearer and can be applied to the top sheet of the absorbent article, and examples thereof include components such as a protein modifier, an anionic surfactant, a salt concentration adjuster, a protease, and a weakly alkalinizing agent. These components are components capable of modifying or decomposing THP to make THP into small pieces or to dissolve THP into water (i.e., soluble in urine), and are also components that can be easily applied to a surface sheet, and therefore, are preferable in that THP contained in the urine of a wearer can be more efficiently and more effectively dispersed. These components may be used alone or in combination of two or more.

In the present invention, the protein modifier that can be used as the protein dispersing unit is not particularly limited as long as it can modify and disperse THP, and a chaotropic salt can be appropriately used. Specific examples of the chaotropic salt include those having a strong protein-modifying effect in Hofmeister series (Hofmeister series) and containing I^-、ClO^4-、SCN^-、Li⁺、Mg²⁺、Ca² ⁺、Ba²⁺、Gu⁺(guanidine salt ion) and urea, among them, guanidine compounds having a guanidine group (for example, guanidine, 1-methylguanidine, arginine, etc.), hydrochloride salts thereof, and urea can be particularly preferably used.

Such a chaotropic salt has a strong modifying effect on THP, and can modify THP so as to improve solubility in water without causing a salting-out effect, and therefore, the blocking of the surface sheet by THP described above can be more reliably and effectively made difficult to occur.

The anionic surfactant that can be used as the protein dispersing unit is not particularly limited as long as it can disperse THP, and Sodium Dodecyl Sulfate (SDS) can be suitably used. The SDS has a strong protein-modifying effect, and even a protein having high hydrophobicity, which is insoluble in other methods, can be solubilized, and the function of the protein can be inactivated, so that the above-mentioned clogging due to THP can be made more difficult to occur. When an anionic surfactant is used as the protein dispersing unit, it is necessary to use the anionic surfactant in an amount of not less than the critical micelle concentration value.

The salt concentration adjusting agent usable as the protein-dispersed portion is not particularly limited as long as the salt concentration in urine can be adjusted to a concentration at which the solubility of THP is increased (i.e., the salt is dissolved), and for example, any salt such as a sodium salt or a potassium salt at a predetermined concentration can be used.

The protease that can be used as the protein dispersing unit is not particularly limited as long as it can decompose THP, and any protease such as serine protease, thiol protease, acid protease, and metalloprotease can be used.

The weak alkalifying agent used as the protein dispersion unit is not particularly limited as long as it can change the urine supplied onto the surface sheet to a weak alkalinity (i.e., a pH in the range of 8.0 to 11.0), and any alkali component can be used.

The position of the surface sheet (nonwoven fabric) to which the protein-dispersing means is applied is not particularly limited as long as the effect of the present invention is not impaired, and for example, the surface sheet may be applied to only either the ridges or the grooves of the surface sheet, or may be applied to both the ridges and the grooves (that is, the entire surface of the skin-facing surface of the surface sheet).

The means for applying the protein-dispersed units to the surface sheet (nonwoven fabric) is not particularly limited as long as the effects of the present invention are not impaired, and for example, an extrusion device provided with a discharge nozzle; non-contact coating machines such as spiral coating machines, curtain coating machines, spray coating machines, dip coating machines, and the like; a contact coater, and the like. In addition, in the case of applying the protein dispersion unit to the whole surface sheetNext, a method of immersing the nonwoven fabric constituting the surface sheet in a solution containing the protein-dispersed units, a method of covering the structural fibers of the nonwoven fabric with the protein-dispersed units in advance, or the like may be used. The amount of the protein-dispersed units applied (applied amount) to the surface sheet (nonwoven fabric) varies depending on the type of the protein-dispersed units, and may be, for example, 1g/m²～300g/m²An amount within the range of (1).

[ Back sheet ]

Next, a back sheet that can be used in the absorbent article of the present invention will be described.

In the light incontinence pad 1 of the above embodiment, as shown in fig. 2, the back sheet 3 is disposed on the non-skin-facing surface side T in the thickness direction T of the light incontinence pad 1₂The position (b) is formed by a liquid-impermeable sheet that functions to prevent the permeation of urine discharged from the wearer and to prevent the urine from leaking out to the underwear of the wearer. The liquid-impermeable sheet usable as the back sheet is preferably impermeable to liquid such as urine and has predetermined air permeability. When the back sheet has such air permeability, moisture released from the absorbent body (specifically, moisture from urine or the like absorbed and held by the absorbent body) is easily released to the outside of the absorbent article through the back sheet, and therefore, it is possible to make it difficult for moisture to accumulate inside the absorbent article or between the absorbent article and the skin surface of the wearer.

The liquid-impermeable sheet usable as the back sheet is not particularly limited, and for example, a hydrophobic nonwoven fabric formed of an arbitrary hydrophobic thermoplastic resin fiber (for example, polyolefin fiber such as Polyethylene (PE) and polypropylene (PP), polyester fiber such as polyethylene terephthalate (PET), and various composite fibers such as a core-sheath type fiber); a porous or nonporous resin film formed of a hydrophobic thermoplastic resin such as PE or PP; a laminate obtained by bonding a nonwoven fabric to the resin film; an optional liquid-impermeable sheet such as a SMS nonwoven fabric is laminated.

The thickness, basis weight, and shape of the back sheet are not particularly limited as long as the effects of the present invention are not impaired, and any thickness, basis weight, shape, and the like can be used according to the desired leakage-proof performance, air permeability, strength, and the like.

[ absorbent body ]

Next, an absorbent body that can be used in the absorbent article of the present invention will be described.

In the light incontinence pad 1 of the above embodiment, the absorbent body 4 is disposed between the front sheet 2 and the back sheet 3, and is formed of an absorbent member having predetermined liquid absorption properties and liquid retention properties, and capable of absorbing and retaining urine that has passed through the front sheet 2. As shown in fig. 1, the absorbent body 4 has a longitudinally long outer shape extending over a wide range in the longitudinal direction L of the light incontinence pad 1 in a plan view, and a substantially central portion in the longitudinal direction L is tapered inward in the width direction W. In the absorbent article of the present invention, the outer shape of the absorbent body is not limited to this form, and any outer shape (for example, a rectangular shape, an oval shape, an hourglass shape, etc.) and dimensions according to various uses and the like can be adopted.

The absorbent member usable as the absorbent body is not particularly limited as long as it can absorb and retain at least urine, and any absorbent member known in the art may be used. Examples of the absorbent member include an absorbent member in which at least one absorbent core made of an absorbent material is covered with a core wrap sheet such as a hydrophilic tissue. Examples of the absorbent material constituting the absorbent core include hydrophilic fibers, highly absorbent polymers, and the like, and more specifically, cellulose fibers such as ground pulp, cotton, rayon, and acetate fibers; a granular material comprising a high-absorbency polymer such as a sodium acrylate copolymer; and mixtures of any combination thereof.

The thickness, basis weight, and the like of the absorbent body are not particularly limited as long as the effects of the present invention are not impaired, and any thickness, basis weight, and the like can be adopted according to desired absorption performance, flexibility, and the like. The thickness, basis weight, and the like of the absorbent body may be constant over the entire surface of the absorbent body, or may be locally different.

In the light incontinence pad 1, the absorbent body 4 is joined to the top sheet 2 on the skin-facing surface by an optional joining method such as a hot-melt adhesive, and is joined to the back sheet 3 on the non-skin-facing surface by an optional joining method such as a hot-melt adhesive.

The present invention can be applied to various absorbent articles such as a panty liner, an incontinence pad (urine pad), and a disposable diaper, which are intended to absorb urine, in addition to the light incontinence pad of the above embodiment. The absorbent article of the present invention is not limited to the above-described embodiments, and the like, and may be appropriately combined, substituted, modified, and the like without departing from the object and spirit of the present invention. In the present specification, ordinal numbers such as "first" and "second" are used to distinguish items to which the ordinal numbers are attached, and do not mean the order, priority, importance, and the like of the items.

Description of the reference numerals

1 light incontinence pad (absorbent article)

2 surface sheet

21 convex strip part

22 groove part

3 Back sheet

4 absorbent body

5 side sheet

Claims

1. An absorbent article comprising a surface sheet and an absorber arranged to overlap in a thickness direction, the absorbent article targeting urine, wherein:

The surface sheet is composed of a non-woven fabric having an uneven structure, a basis weight of 25 g/m ² to 50 g/m ² and a thickness of 0.7 mm to 2.0 mm. Alternately arranged along a second direction orthogonal to the first direction, the ridges protrude toward the skin-facing surface side of the absorbent article in the thickness direction, and extend in the first direction, the The groove portion is recessed toward the non-skin-facing surface side of the absorbent article in the thickness direction, and extends in the first direction in parallel with the ridge portion,

In addition, the surface sheet has a high-density portion having a relatively high fiber density in the groove portion, and has a protein dispersing unit for dispersing Tamm-Horsfall protein contained in urine on the surface of the skin-facing surface side.

2. The absorbent article of claim 1, wherein:

The protein dispersing unit is at least one component selected from the group consisting of a protein modifier, an anionic surfactant, a salt concentration modifier, a proteolytic enzyme, and a weakly basicizing agent.

3. The absorbent article of claim 2, wherein:

The protein dispersing unit is the protein modifier, and the protein modifier is a chaotropic salt.

4. The absorbent article of claim 2, wherein:

The protein dispersing unit is the anionic surfactant, and the anionic surfactant is sodium lauryl sulfate.

5. The absorbent article according to any one of claims 1 to 4, wherein

The thickness of the protruding strip portion of the surface sheet is larger than the thickness of the groove portion by 0.3 mm to 1.5 mm, the protruding strip portion has a width of 2.0 mm to 4.0 mm, and the groove portion has a width of 0.5 mm to 2.0 mm width.