Absorbent article containing lubricant

Abstract

The present disclosure relates to an absorbent article (100) comprising a liquid-permeable topsheet (102), a backsheet (103), and an absorbent core (104) sandwiched between the topsheet (102) and the backsheet (103), wherein the absorbent article (100) extends in a longitudinal direction (L) and a transverse direction (T), and the absorbent article (100) defines, as viewed in the longitudinal direction, a front waist portion (105), a rear waist portion (106), a crotch portion (107) disposed between the rear waist portion and the front waist portion (105), and a hip portion (108) disposed between the crotch portion (107) and the rear waist portion (106). The topsheet (102) comprises a first lubricant zone (109) containing a lubricant, the first lubricant zone (109) being disposed above the hip portion (108).

Description

[Technical field]

[0001] The present disclosure relates to absorbent articles and belt-type absorbent articles with reduced friction. In particular, the present disclosure relates to absorbent articles and belt-type absorbent articles with a topsheet coated with a lubricant in a first lubricant zone. [Background technology]

[0002] The absorbent article of the kind to which this disclosure relates is applied to the skin with the top sheet facing the skin of the user. Any use of a product in direct contact with the skin can lead to undesirable side effects. These can occur as a result of mechanical factors such as blockage, moisture, and friction between the skin and the absorbent article. All these factors can interact to different degrees and amplify each other's effects, causing different forms of skin irritation to the user of said article. Although the body-facing material is made of a soft and flexible material, it can be rubbed against the skin during use, causing the skin to not be completely dry and free of body fluids. After getting wet, mechanical friction, especially the so-called wet friction between the material and the skin, can increase the risk of skin irritation.

[0003] One reason for mechanical discomfort is related to cling, i.e. the forces acting between absorbent products and human skin in the presence of small amounts of moisture such as perspiration, sweat and urine. Sticking can be described as a normal force acting between a solid material and a support surface in the presence of small amounts of moisture. Wet friction occurs between a wet or damp product and the skin. Wet friction can occur even when there is a small amount of moisture or liquid present within or at the interface of the product between a surface material and the skin. Dry friction occurs between a dry product and the skin.

[0004] The friction between the absorbent article and the user's skin and the pressure applied to the top sheet material can cause discomfort and skin irritation, especially for bedridden caregivers who use incontinence articles a lot and absorbent articles used at night. Bedridden caregivers often stay in the same position for long periods of time, which puts high pressure on certain areas of the body. In particular, the pressure on the sacrum can be high because the caregiver spends a lot of time lying on their back.

[0005] When changing absorbent articles for bedridden caregivers, especially at night, the caregiver often asks the patient to lift up their buttocks, pulls the used article out from under the caregiver, and places a new article under the buttocks that is placed under the caregiver's buttocks. Alternatively, the caregiver turns from one side so that the article is folded under the patient, and then turns to the other side so that the soiled article can be removed and a new article can be applied to the caregiver. However, in both cases, removal of the soiled article often involves the rear / buttock portion of the absorbent article being pulled out from under the patient, resulting in friction between the rear / buttock portion of the absorbent article, side panels or absorbent belts and the caregiver's skin.

[0006] Thus, both wetness and the caregiver's movement patterns can result in higher shear forces in certain areas of the absorbent article.

[0007] Creams, lotions, or ointments may be used to reduce friction and improve skin condition. However, the use of such hydrophobic compositions can adversely affect the absorbent performance of absorbent articles, and the transfer of materials and compositions to the skin of the user is not always desirable. Summary of the Invention [Problem to be solved by the invention]

[0008] It is an object of the present invention to provide a belt-type absorbent article, such as an absorbent article and / or a heavy incontinence article, that provides improved skin benefits after prolonged use and heavy wetness. [Means for solving the problem]

[0009] One or more of the above mentioned objects may be achieved by an absorbent article according to claim 1 and / or a belt-type absorbent article according to claim 28. Further advantages and advantageous features of the present invention are disclosed in the following description and the dependent claims.

[0010] In a first aspect, the disclosure relates to an absorbent article, such as a diaper or adult incontinence article, comprising a liquid permeable topsheet, a backsheet, and an absorbent core sandwiched between the topsheet and the backsheet. The absorbent article extends in a longitudinal direction and a transverse direction. In a longitudinal direction, the absorbent article defines a front waist portion, a rear waist portion, and a crotch portion disposed between the front waist portion and the rear waist portion. A hip portion is disposed between the crotch portion and the rear waist portion. The topsheet includes a first lubricant zone provided with a lubricant, the first lubricant zone being disposed over the hip portion.

[0011] The term "absorbent article" refers to a product that is placed against the skin of a wearer to absorb and contain bodily exudates such as urine and feces. This application primarily refers to disposable absorbent articles, meaning articles that are not intended to be washed or restored or reused as absorbent articles. Disposable absorbent articles include pant diapers, open diapers, belt-type absorbent articles, and the like.

[0012] The topsheet of the absorbent article is the layer that faces the wearer during use. The topsheet can be a fibrous nonwoven layer.

[0013] The hip portion is the portion of the absorbent article that faces the sacral region of the wearer during use. The hip portion may extend between the rear edge of the absorbent core and a lateral transition line located at a distance of 40% of the total length of the absorbent article from the rear waist edge of the absorbent article. The hip portion overlies the longitudinal centerline of the absorbent article.

[0014] The friction generated between a top sheet material, such as a nonwoven material or a perforated plastic film or net, and the skin of a user is different than when no liquid / moisture is present. Even very small amounts of moisture present, such as when the moisture comes from sweat or other body fluids, affect the frictional forces generated between the surface material and the skin of the user. It has therefore been found important to carefully design the absorbent properties and surface layer of an absorbent article so that the overall mechanical discomfort during use of the product is reduced.

[0015] Bedridden caregivers often remain in the same position for long periods of time without changing positions, especially lying on their backs. Thus, pressure on certain areas of the body, such as the sacral area, may be high in areas that correspond to the buttocks area of ​​the absorbent article. When removing the absorbent article, especially at night, pressure from the caregiver's body is applied to this area, creating high friction between the rear / buttocks area of ​​the absorbent article. Because bedridden caregivers are often elderly caregivers, the skin of these caregivers is often thinner and more fragile, increasing the importance of reducing friction.

[0016] The Rewet Under Pressure value is based on the measurement of the absorbent article's ability to retain 0.9% saline solution in the pressure areas of the absorbent article under simulated in-use pressure conditions when the user of the absorbent article is lying down. A method for measuring the Rewet Under Pressure value is disclosed herein below. Low rewet in the pressure areas, i.e. dry zones in the sacral and perineal regions, leads to reduced wet friction in areas where shear forces can be high, especially for bedridden caregivers. The Rewet Under Pressure method is disclosed herein below and involves the addition of five 100 ml doses of 0.9NaCl solution. With the absorbent article under compression for 6 hours, the Rewet 3 value is measured after the third application, the Rewet 4 value is measured after the fourth application, the Rewet 5 value is measured after the fifth application, and the Rewet 6 value is measured 6 hours after the fifth application.

[0017] The article may have a Rewet 6 value of 20 gsm or less, or 15 gsm or less, or 13 gsm or less, or 11 gsm or less, as measured by the Rewet Under Pressure method disclosed herein.

[0018] The inventors have discovered that when a lubricant is provided to the posterior region of a topsheet of an absorbent article having a Rewet 6 value according to the present disclosure, a surprising and significant reduction in mechanical discomfort can be obtained and the skin health of the user of the absorbent article can be significantly improved after prolonged use and / or significant wetting.

[0019] The absorbent article may have a Rewet 5 value of 30 gsm or less, or 23 gsm or less, when measured by the Rewet Under Pressure method after the fifth application as disclosed herein, such as in the range of 5 gsm to 23 gsm.

[0020] The absorbent article may have a Rewet 4 value of 20 gsm or less, or 12 gsm or less, when measured by the Rewet Under Pressure method after the fourth application as disclosed herein, such as in the range of 2 gsm to 12 gsm.

[0021] The absorbent article may have a Rewet 3 value of 10 gsm or less, or 5.5 gsm or less, when measured by the Rewet Under Pressure method after the third application as disclosed herein, such as in the range of 1 gsm to 5.5 gsm.

[0022] The first lubricant zone may be located in the buttocks portion and the rear waist portion. The rear waist portion may be a central rear waist portion. The rear waist portion may include a central rear waist portion and first and second lateral rear waist portions located on either side of the central rear waist portion in a transverse direction.

[0023] The rear waist portion extends from the rear waist edge toward the buttocks portion of the absorbent article. The rear waist portion may extend between the rear end edge of the absorbent core and the rear waist edge.

[0024] The first lubricant zone is intended to be placed in contact with the caregiver's sacral region, an area that is often exposed to high pressure levels during use of the absorbent article, especially when lying down.

[0025] The first lubricant zone is 25 cm 2 Above, optional 25cm2 From 600cm 2 The surface area may be in the range of 0.1 to 100 mm.

[0026] The first lubricant zone can have a surface area of ​​from 1 to 30% of the total surface area of ​​the topsheet, or from 2 to 25%, or from 5 to 20% of the total surface area of ​​the topsheet.

[0027] The amount of lubricant in the first lubricant zone (109) can be from 10 ppm to 10 wt.% based on the total weight of the topsheet in the first lubricant zone (109), or from 0.05 wt.% to 2 wt.%, or from 0.1 wt.% to 2 wt.% based on the total weight of the topsheet in the first lubricant zone (109).

[0028] Optionally, the topsheet may contain from 0.3 to 4.0 gsm of lubricant, or from 0.3 to 2.0 gsm of lubricant, measured across the first lubricant zone, such levels have been found to provide improved wet friction.

[0029] The lubricant may be applied by any suitable method or combination of methods, such as, for example, spraying, kiss rolling, or dipping. For application methods that require the lubricant to be mixed with water prior to application, the lubricant may have an HLB in the range of 8 to 18 to mix well with water.

[0030] "HLB" in this specification means hydrophilic-lipophilic balance. As known to those skilled in the art, the HLB of a compound is a measure of the degree of lipophilicity or hydrophilicity. The HLB value can be determined by calculating the values ​​of different regions of a compound. One method for determining the HLB value is the Griffin method described in Journal of the Society of Cosmetic Chemists, 5 (4): 249-56, 1954.

[0031] The lubricant may have a molecular weight of 500 g / mol or more, or, for example, 1000 g / mol or more. A lubricant with a molecular weight of 500 g / mol or more or 1000 g / mol or more is less prone to migrate downward from the fibrous nonwoven to the skin of the user and / or into the absorbent article, such as the underlying absorbent core. This therefore extends the effect of the lubricant on the wearer-facing side of the absorbent article. Furthermore, the lubricant may have a molecular weight of 500 g / mol or more or 1000 g / mol or more, so that if some of the lubricant migrates from the fibrous nonwoven to the skin of the user, it does not pass through the skin barrier.

[0032] The lubricant is applied to the coating, and the coating containing the lubricant can be 5.0% by weight or less, or 1.0% by weight or less. Thus, the coating can be a lubricant with a moisture content of 5.0% by weight or less, or 1.0% by weight or less. The coating provided on the topsheet is intended to remain on the topsheet throughout the use of the absorbent article, and a relatively dry coating remains on the topsheet more than a liquid or semi-liquid composition that is prone to transfer from the topsheet. The fact that the coating can be a relatively dry coating has been found to enhance the wet friction reduction effect over time. It is also beneficial that the lubricant can have a moisture content of 5.0% by weight or less, or 1.0% by weight or less, because the lubricant can remain more in the buttocks area.

[0033] The topsheet may include at least one surface zone that is a lubricant-free zone. There may also be a lubricant-free zone in the crotch region. The lubricant-free zone in the crotch region may extend beyond 50 cm 2 Above, 50cm optional 2 From 600cm 2 The front waist portion may also have a lubricant-free zone.

[0034] For bedridden caregivers, both the front waist and crotch areas are in contact with the skin during use, however, even though these areas are in contact with the skin during use, the areas do not exert pressure against the skin and the shear forces between the skin and the topsheet in these areas are not significant.

[0035] The topsheet may include a second lubricant zone, and the amount of lubricant in the second lubricant zone may be less than the first lubricant zone.

[0036] The amount of lubricant in the first lubricant zone may be at least 25% greater than the second lubricant zone.

[0037] A second lubricant zone may be provided in the rear waist portion of the user-facing side of the article. The second lubricant zones may be disposed on each lateral side of the first lubricant zone.

[0038] The lubricant may be any one or combination of a wax, a lubricant containing an alkoxylated diester selected from the group consisting of fatty acid ester lubricants, or a lubricant containing a silicone oil. The alkoxylated diester may be an alkoxylated diester of myristyl alcohol and adipic acid. The silicone oil may be polydimethylsiloxane.

[0039] The thickness of the absorbent article in the hip area may be 4mm or more at 0.5kPa when measured according to WSP120.6.R4 (12). Optionally, the thickness of the absorbent article in the hip area may be 5mm or more at 0.5kPa, or 6mm or more at 0.5kPa, for example up to 30mm.

[0040] The backsheet may be a moisture permeable backsheet that provides a Water Vapor Transmission Rate (WVTR) of at least 3500 grms per square meter per 24 hours.

[0041] The breathable backsheet reduces surface layer moisture, which in combination with the lubricant and low Rewet Under Pressure values ​​promotes skin health and reduces friction between the absorbent article and the wearer's skin.

[0042] The topsheet may be a fibrous nonwoven layer, optionally consisting essentially of thermoplastic fibers, such as polyolefin fibers.

[0043] The absorbent core includes a first absorbent layer and a second absorbent layer, the first absorbent layer having a first absorbent layer front edge and a first absorbent layer rear edge, and the second absorbent layer having a second absorbent layer front edge and a second absorbent layer rear edge, each having a size and shape in the plane of the absorbent article. The size and shape of the second absorbent layer can define the size and shape of the absorbent core in the plane of the absorbent article, and the first absorbent layer can be shorter than the second absorbent layer as viewed in the longitudinal direction of the absorbent article.

[0044] Each of the first and second absorbent layers may include a superabsorbent polymer.

[0045] The first absorbent layer is an upper absorbent layer and the second absorbent layer is a lower absorbent layer, and the amount of superabsorbent polymer in the upper absorbent layer is 1.6 times greater than in the lower absorbent layer, optionally 1.7 times greater than in the lower absorbent layer, and optionally the amount in the upper absorbent layer can be up to 4 times greater than in the lower absorbent layer.

[0046] The first absorbent layer front edge is positioned a front edge distance d1 from the second absorbent layer front edge, and the first absorbent layer rear edge is positioned a rear edge distance d2 from the second absorbent layer rear edge, and the ratio of the front edge spacing d1 to the rear edge spacing d2 may be 1.5 or greater.

[0047] The absorbent article includes a transfer layer disposed between the topsheet and the absorbent core, the transfer layer may have a transfer layer front edge and a transfer layer rear edge, the transfer layer front edge is disposed a second front edge distance d3 from the second absorbent layer front edge, the transfer layer rear edge is disposed a second rear edge distance d4 from the second absorbent layer rear edge, and a ratio of the second front edge distance d3 to the second rear edge distance d4 may be equal to or greater than 1.

[0048] The rear waist portion of the absorbent article may be free of elastic yarns.

[0049] The article may be constituted by a diaper or an incontinence article, such as an absorbent article of the open diaper type, a pant diaper or a belt type.

[0050] The absorbent article may be an adult incontinence absorbent article.

[0051] The absorbent article may be an overnight absorbent article.

[0052] According to a second aspect, the present disclosure relates to a belt-type absorbent article. The absorbent article is a belted absorbent article comprising an absorbent pad and a separate belt to which the pad is removably attached, the belt being placed around the wearer's waist to hold the pad when the article is worn. The absorbent pad comprises a liquid-permeable topsheet, a backsheet, and an absorbent core sandwiched between the topsheet and the backsheet. The absorbent pad extends in the longitudinal and transverse directions. The absorbent pad defines, in the longitudinal direction, a front waist portion, a rear waist portion, and a crotch portion disposed between the rear waist portion and the front waist portion. A hip portion is disposed between the crotch portion and the rear waist portion. A first lubricant zone is disposed on the topsheet of the hip portion of the absorbent article. The separate belt is provided with a lubricant in the belt lubricant zone.

[0053] The amount of lubricant in the belt lubrication zone is cm 2The amount of lubricant in the belt lubricant zone may be less than the amount of lubricant in the first lubricant zone, as measured in grams of lubricant per square meter (gsm), i.e., grams per square meter (gsm). The amount of lubricant in the belt lubricant zone may be at least 10% less than the first lubricant zone. The amount of lubricant in the belt lubricant zone may be at least 20% or 30% less than the first lubricant zone. The amount of lubricant in the belt lubricant zone may be 20% to 80% less than the first lubricant zone.

[0054] The first lubricant zone may be located in both the hip portion and the rear waist portion. The rear waist portion may be a central rear waist portion. The rear waist portion may include a central rear waist portion and first and second lateral rear waist portions disposed on respective lateral sides of the central rear waist portion in the transverse direction. The hip portion may overlap the aftmost portion of the absorbent core.

[0055] The belt-type absorbent article may be an overnight absorbent article.

[0056] The belt-type absorbent article according to the second embodiment of the present disclosure has a front and a rear waist region and covers a relatively large area of ​​the lower torso, which may cause blockages in certain parts of the skin, thereby causing overhydration of the skin. Also, the belt fits tightly around the waist of the user, which may cause friction when the user moves around while wearing the belt-type absorbent article. The friction generated between a topsheet material, such as a nonwoven material, and the skin of the user is different in the absence of liquid / moisture than in the presence of liquid / moisture. Even a very small amount of moisture from sweat or other body fluids affects the frictional force generated between the topsheet material and the skin of the user.

[0057] It has been found that one of the main causes of mechanical discomfort is related to "cling", i.e. the forces acting between absorbent products and human skin in the presence of moisture (perspiration, sweat, urine). Absorbent products reduce friction between the user's skin and the product not only when the area is substantially dry, but also when the area is moistened by the presence of sweat or other body fluids.

[0058] Bedridden caregivers often spend long periods of time lying down, especially on their backs, without changing positions. Thus, pressure on certain areas of the body, such as the sacral area, may be high in the area of ​​the absorbent article that corresponds to the buttocks area. When removing a belt-type absorbent article, pressure from the caregiver's body is applied to this area, creating high friction between the rear / buttocks portion of the absorbent article. When pulling the absorbent article downwards, the belt may also come into contact with the caregiver's buttocks area, resulting in high shear forces. This is often the case with older caregivers, whose skin is often thinner and more vulnerable, increasing the importance of reducing friction.

[0059] The rear waist portion extends from the rear waist edge of the absorbent pad toward the buttocks portion. The rear waist portion may extend between the rear end edge of the absorbent core and the rear waist edge.

[0060] The buttock portion is the portion of the absorbent pad that faces the wearer's sacral region during use. The buttock portion may extend between the rear edge of the absorbent core and a transverse transition line located at a distance of 40% of the total length of the absorbent article from the rear waist edge of the absorbent article. The buttock portion overlies the longitudinal centerline of the absorbent pad.

[0061] The length of the crotch portion may be 20% to 25% of the length of the absorbent pad and may be positioned equidistant to the front and rear waist edges of the absorbent pad.

[0062] The length of the hip section may be 25% to 35% of the length of the absorbent pad.

[0063] The first lubricant zone is positioned to contact the caregiver's sacral region, an area that is often exposed to high pressure levels during use of the absorbent article, especially when lying down.

[0064] The lubricant may be applied by several different methods, such as spraying, kiss rolling, or dipping. For application methods that require the lubricant to be mixed with water prior to application, the lubricant may have an HLB in the range of 8 to 18 in order to mix well with water.

[0065] The absorbent pad may have a Rewet 6 value of 20 gsm or less, or 13 gsm or less, as measured by the Rewet Under Pressure method disclosed herein. The inventors have discovered that providing a lubricant to the buttocks area of ​​a topsheet of an absorbent article having a Rewet 6 value according to the present disclosure can achieve a surprisingly large reduction in mechanical discomfort and improve the skin health of a user of the belt-type absorbent article during prolonged use of the belt-type absorbent article and / or after significant wetting.

[0066] The Rewet Under Pressure value is based on a measurement of the absorbent article's ability to retain 0.9% saline under simulated in-use pressures and pressure areas in a lying position. Methods for measuring the Rewet Under Pressure value are disclosed herein below.

[0067] "HLB" in this specification means hydrophilic-lipophilic balance. As known to those skilled in the art, the HLB of a compound is a measure of the degree of lipophilicity or hydrophilicity. The HLB value can be determined by calculating the values ​​of different regions of a compound. One method for determining the HLB value is the Griffin method described in Journal of the Society of Cosmetic Chemists, 5 (4): 249-56, 1954.

[0068] The lubricant may have a molecular weight of 500 g / mol or more, or, for example, 1000 g / mol or more. A lubricant with a molecular weight of 500 g / mol or more or 1000 g / mol or more is less prone to migrate downward from the fibrous nonwoven to the skin of the user and / or into the absorbent article, such as the underlying absorbent core. This therefore extends the effect of the lubricant on the wearer-facing side of the absorbent article. Furthermore, the lubricant may have a molecular weight of 500 g / mol or more or 1000 g / mol or more, so that if some of the lubricant migrates from the fibrous nonwoven to the skin of the user, it does not pass through the skin barrier.

[0069] The lubricant is applied to the coating, and the coating containing the lubricant can have a moisture content of less than 5.0 weight percent or less than 1.0 weight percent. The coating provided on the topsheet is intended to remain on the topsheet throughout the use of the absorbent article, and the coating with a moisture content of less than 5.0 weight percent or less than 1.0 weight percent remains on the topsheet more than a liquid or semi-liquid composition that may be prone to transfer from the topsheet and from the buttocks area. It has also been found that the coating has a moisture content of less than 5.0 weight percent or less than 1.0 weight percent, which enhances the wet friction reduction effect over time.

[0070] The topsheet may include at least one surface zone that is a lubricant-free zone. There may also be a lubricant-free zone in the crotch region. The lubricant-free zone in the crotch region may extend beyond 50 cm 2 Above, 50cm optional 2 From 600cm 2 The front waist portion may also have a lubricant-free zone.

[0071] For bedridden caregivers, both the front waist and crotch areas are in contact with the skin during use, however, even though these areas are in contact with the skin during use, the areas do not exert pressure against the skin and the shear forces between the skin and the topsheet in these areas are not significant.

[0072] The topsheet may include a second lubricant zone, and the amount of lubricant in the second lubricant zone may be less than the first lubricant zone.

[0073] The amount of lubricant in the first lubricant zone may be at least 25% greater than the second lubricant zone.

[0074] A second lubricant zone may be provided in the rear waist portion of the user-facing side of the article. The second lubricant zones may be disposed on each lateral side of the first lubricant zone.

[0075] The lubricant may be any one or combination of a wax, a lubricant containing a silicone oil, or a lubricant containing an alkoxylated diester selected from the group consisting of fatty acid ester lubricants. The alkoxylated diester may be an alkoxylated diester of myristyl alcohol and adipic acid. The silicone oil may be polydimethylsiloxane.

[0076] The thickness of the absorbent article in the hip area may be 4mm or more at 0.5kPa when measured according to WSP120.6.R4 (12). Optionally, the thickness of the absorbent article in the hip area may be 5mm or more at 0.5kPa, or 6mm or more at 0.5kPa, for example up to 30mm.

[0077] The backsheet may be a moisture permeable backsheet that provides a Water Vapor Transmission Rate (WVTR) of at least 3500 grms per square meter per 24 hours.

[0078] The breathable backsheet reduces surface layer moisture, which in combination with the lubricity and low Rewet Under Pressure values ​​promotes skin health and reduces friction between the absorbent article and the wearer's skin.

[0079] The topsheet may be a fibrous nonwoven layer, optionally consisting essentially of thermoplastic fibers, such as polyolefin fibers.

[0080] The absorbent core includes a first absorbent layer and a second absorbent layer, the first absorbent layer having a first absorbent layer front edge and a first absorbent layer rear edge, and the second absorbent layer having a second absorbent layer front edge and a second absorbent layer rear edge, each having a size and shape in the plane of the absorbent article. The size and shape of the second absorbent layer can define the size and shape of the absorbent core in the plane of the absorbent article, and the first absorbent layer can be shorter than the second absorbent layer as viewed in the longitudinal direction of the absorbent article.

[0081] Each of the first and second absorbent layers may include a superabsorbent polymer.

[0082] The first absorbent layer is an upper absorbent layer and the second absorbent layer is a lower absorbent layer, and the amount of superabsorbent polymer in the upper absorbent layer is 1.6 times greater than in the lower absorbent layer, optionally 1.7 times greater than in the lower absorbent layer, and optionally the amount in the upper absorbent layer can be up to 4 times greater than in the lower absorbent layer.

[0083] The first absorbent layer front edge is positioned a front edge distance d1 from the second absorbent layer front edge, and the first absorbent layer rear edge is positioned a rear edge distance d2 from the second absorbent layer rear edge, and the ratio of the front edge spacing d1 to the rear edge spacing d2 may be 1.5 or greater.

[0084] The absorbent article includes a transfer layer disposed between the topsheet and the absorbent core, the transfer layer may have a transfer layer front edge and a transfer layer rear edge, the transfer layer front edge is disposed a second front edge distance d3 from the second absorbent layer front edge, the transfer layer rear edge is disposed a second rear edge distance d4 from the second absorbent layer rear edge, and a ratio of the second front edge distance d3 to the second rear edge distance d4 may be equal to or greater than 1. [Brief description of the drawings]

[0085] The invention is further described below, by way of non-limiting examples, with reference to the accompanying drawings, in which:

[0086] [Figure 1] 1 shows an absorbent article according to the present disclosure. [Diagram 2] 1 shows a belt-type absorbent article according to the present disclosure. [Diagram 3] 1 shows a fixture for use in the Rewet Under Pressure method disclosed herein. [Figure 4a] 1 shows one of two leg blocks for use in the rewetting under pressure method disclosed herein. [Figure 4b] 1 shows one of two leg blocks for use in the rewetting under pressure method disclosed herein. [Figure 4c]1 shows one of two leg blocks for use in the rewetting under pressure method disclosed herein. [Figure 5a] 1 shows a hip template for use in the rewetting under pressure method disclosed herein. [Figure 5b] 1 shows a hip template for use in the rewetting under pressure method disclosed herein. [Figure 6] 1 shows a stretched absorbent article that has been cut and marked along a side seam prior to testing with the Rewet Under Pressure method disclosed herein. [Figure 7a] 1 shows an absorbent article tested with the Rewet Under Pressure method disclosed herein. [Figure 7b] 1 shows an absorbent article tested with the Rewet Under Pressure method disclosed herein. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0087] The present invention will now be described in more detail with reference to exemplary embodiments, however the invention may be embodied in many different forms and should not be construed as limited to the embodiments shown in the drawings and its description.

[0088] FIG. 1 illustrates a schematic of an absorbent article 100 according to the present disclosure. The absorbent article 100 is a pant-type absorbent article. The absorbent article includes a liquid permeable topsheet 102, a backsheet 103, and an absorbent core 104 sandwiched between the topsheet 102 and the backsheet 103. The absorbent article 100 extends in a longitudinal direction L and a transverse direction T. As seen in the longitudinal direction L, the absorbent article 100 defines a front waist portion 105, a rear waist portion 106, and a crotch portion 107 disposed between the front waist portion 105 and the rear waist portion 106.

[0089] The topsheet 102 includes a first lubricant zone 109 provided with a lubricant, the first lubricant zone 109 being disposed over the buttocks portion 108 and the central portion 106a of the rear waist portion 106, and aligned with the longitudinal centerline C of the absorbent article 100. L The amount of lubricant in the first lubricant zone 109 is at least 0.1% by weight of the topsheet, measured over the entire coated area. Optionally, the topsheet may contain 0.3% or 0.5% by weight of lubricant, measured over the entire coated area. Such levels have been found to provide improved wet friction.

[0090] The topsheet may comprise or consist of fibrous nonwoven layers, such as spunbonded, meltblown, carded, hydroentangled, wetlaid, etc. Suitable nonwoven materials may consist of natural fibers, such as wood pulp or cotton fibers, synthetic thermoplastic fibers, such as polyolefins, polyesters, polyamides, and blends and combinations thereof, or mixtures of natural and synthetic fibers. Suitable topsheet materials are soft, non-irritating to the skin, and permeable to bodily fluids, such as urine. The topsheet material may consist essentially of synthetic thermoplastic fibers, such as polyolefins, polyesters, polyamides, and blends and combinations thereof. The synthetic fibers may be monocomponent fibers, bicomponent fibers, or multicomponent fibers, including polyesters, polyamides, and / or polyolefins, such as polypropylene and polyethylene. The topsheet and fibrous nonwoven layers may "consist essentially of" thermoplastic synthetic fibers, meaning that at least 95% of the fibers are thermoplastic synthetic fibers, e.g., at least 99%, at least 100% of the fibers in the nonwoven material are non-absorbent fibers. However, the topsheet and fibrous materials may contain additional substances present in small amounts, such as, for example, binders and pigments, as known to those skilled in the art.

[0091] The backsheet may be constructed from thin plastic films, such as polyethylene or polypropylene films, nonwoven materials coated with liquid impermeable materials, hydrophobic nonwoven materials that resist liquid penetration. Laminates of plastic films and nonwoven materials may also be used. The backsheet material may be breathable, allowing vapors to escape from the absorbent structure while preventing liquids from passing through the backsheet material. Alternatively, the backsheet material may be non-breathable.

[0092] The front waist portion 105 and the rear waist portion 106 are intended to be joined together along two opposing longitudinal lateral edges 116, 117, 118, 119 to define a waist opening and a pair of leg openings. The absorbent article 100 shown in Figure 1 includes front elastics 120 in the front waist portion 105 and rear elastics 121 in the rear waist portion 6 and partial buttock portion 108. Each of the front elastics 120 and rear elastics 121 extends in the transverse direction T of the absorbent article 100 between the opposing longitudinal lateral edges 116, 117, 118, 119, respectively. The front waist portion 105 has a front waist edge 105a and the rear waist portion 106 has a rear waist edge 106a.

[0093] The absorbent core 104 includes a first absorbent layer 114 and a second absorbent layer 115. The first absorbent layer 114 is an upper absorbent layer disposed between the topsheet 102 and the second absorbent layer 115. The first absorbent layer 114 has a first absorbent layer front edge 114a and a first absorbent layer rear edge 114b. The second absorbent layer 115 has a second absorbent layer front edge 115a and a second absorbent layer rear edge 115b. The absorbent layers 114, 115 each have a size and shape in the plane of the absorbent article 100, and the size and shape of the second absorbent layer 115 define the size and shape of the absorbent core 104 in the plane of the absorbent article 100. The first absorbent layer 114 is shorter than the second absorbent layer 115 as viewed in the longitudinal direction L of the absorbent article 100. The first absorbent layer front edge 114a is disposed a front edge distance d1 from the second absorbent layer front edge 115a, and the first absorbent layer rear edge 114b is disposed a rear edge distance d2 from the second absorbent layer rear edge 115b, the ratio of the front edge distance d1 to the rear edge distance d2 being equal to or greater than 1.5. Thus, the first absorbent layer 114 is disposed further rearward than the second absorbent layer 115.

[0094] The hip portion 108 is disposed between the crotch portion 107 and the rear waist portion 106. In this view, the transition between the crotch portion 107 and the hip portion 108 is disposed 40% of the total length of the absorbent article 100 from the rear waist edge 106b, where the length of the hip portion 108 is 25% to 35% of the total length of the absorbent core 104. In this view, the transition between the rear waist portion 106 and the hip portion 108 coincides with the first absorbent layer rear edge 114b.

[0095] The absorbent core can be of any conventional type. Examples of commonly occurring absorbent materials are cellulosic fluff pulp, tissue layers, highly absorbent polymers (so-called superabsorbents), absorbent foam materials, absorbent nonwoven materials, etc. It is common to combine cellulosic fluff pulp with superabsorbents into an absorbent structure. It is also common to have absorbent structures that include layers of different materials with different properties in terms of liquid acquisition capacity, liquid distribution capacity, and storage capacity. For example, each of the first and second absorbent layers 14, 15 can include a superabsorbent polymer. The first absorbent layer 14 can have a greater amount of superabsorbent article than the second absorbent layer 15.

[0096] FIG. 2 shows a belt-type absorbent article 200. The belt-type absorbent article 200 includes an absorbent pad 216 and a separate belt 217 to which the pad is removably attached and which is placed around the wearer's waist to hold the pad when worn. The absorbent pad 217 includes a liquid-permeable topsheet 202, a backsheet 203, and an absorbent core 204 sandwiched between the topsheet 202 and the backsheet 203. The absorbent pad extends in a longitudinal direction L and a transverse direction T. As viewed in the longitudinal direction L, the absorbent pad defines a front waist portion 205, a rear waist portion 206, a crotch portion 207 disposed between the rear waist portion 206 and the front waist portion 205, and a hip portion 208 disposed between the crotch portion 207 and the rear waist portion 206. The absorbent article 200 includes a first lubricant zone 209 disposed on the topsheet 202 in the hip portion 208. A first lubrication zone 209 is lubricated. A separate belt is lubricated in a belt lubrication zone 210.

[0097] The absorbent pad 216 or the separate belt 217 may be provided with attachment elements, such as pieces of hook-adhesive material, disposed on a surface intended to face the separate belt 217 or the absorbent pad 216, respectively. One of the absorbent pads 216 or the separate belts 217 may be provided with a corresponding attachment element or may have a surface to which the hook or adhesive material may adhere. When the attachment element is a hook material, such material may be a non-woven material.

[0098] The hip section 208 is disposed over the absorbent core 204 and is positioned in the area that contacts the wearer's sacral region.

[0099] The amount of lubricant in the belt lubrication zone is cm 2 3. The amount of lubricant in the first lubricant zone 9 is less than the amount of lubricant in the first lubricant zone 9, as measured in grams of lubricant per unit area.

[0100] Test Method - Rewet Under Pressure The Rewet Under Pressure method measures the rewet under pressure after repeated wetting of a product, simulating the conditions of use of heavy incontinence articles after repeated wetting.

[0101] "Device" 1. Fixture 1 made of polished aluminium (see Figure 3). The fixture 1 comprises a first plate 2 with dimensions 200x420 mm and a second plate 3 with dimensions 200x300 mm. The second plate 3 is arranged at an angle α of 60° to the first plate 2.

[0102] 2. The two leg blocks 4, 5 are made of a hard plastic material (see Figure 3 and Figures 4a-4c). Each leg block 4, 5 has a height h of 35 mm measured at its highest height and a length l of 120 mm measured at the longest length of each leg block 4, 5. The width of each leg block 4, 5 along the centre line C is 45 mm. Each leg block 4, 5 has a corresponding inner vertical rectangular side 4a, 5a measuring 35×55 mm and arranged to press against a longitudinal side of the diaper placed in the fastener 1. On each side of the inner rectangular side 4a, 5a, each leg block 4, 5 has a corresponding first block side wall 4b, 5b and a second block side wall 4c, 5c. The block side walls 4b, 5b, 4c, 5c are angled upwards and inwards and are disposed between the respective inner rectangular side walls 4a, 5a and the respective first and second rectangular side walls 4d, 4e, 5d, 5e, each having dimensions of 20x20mm. The second rectangular side walls 4e, 5e of the side blocks 4, 5 are vertically aligned with the junction between the first plate 2 and the second plate 3. The leg blocks 4, 5 are movable transversely of the fixture 1 and may be locked in place, for example via screws or magnets.

[0103] 3. Distance template (not shown). A rectangular steel block with dimensions of 40x80mm, approximately 20mm in height.

[0104] 4. A hip template 6 made of PMMA (poly(methyl methacrylate)) or similar, having a base plate 7 with a length l7 of 175 mm, a width w7 of 150 mm and a thickness t7 of 6 mm (shown in Figure 3 and Figures 5a, 5b). The hip template 6 has a template wall 8 with a height h8 of 45mm. The template wall 8 has three wall portions 8a, 8b, 8c with a first side wall portion 8a, an anterior wall portion 8b and a second side wall portion 8c. The anterior wall portion 8b is 50mm wide and 45mm high. The longitudinal sides 7a, 7b of the base plate 7 each have a length of 115mm measured from the rear edge of the base plate 7 to the respective side wall portion 108a, 108c.

[0105] 5. Metal weight is 9, 10kg.

[0106] 6. A liquid pump 11 (shown in FIG. 7b) capable of a delivery rate of 10 ml / sec. The pump 11 is connected to a tube 12 with an internal diameter of 3 mm.

[0107] 7. Collagen film available from Viscofan, Spain. This film is designated Coffi (transparent, product number 706). The film is wrapped in plastic and stored in the refrigerator. For the rewet measurement, 8 sheets are stacked and cut or punched to dimensions of 70x80mm. The pads (8 sheets) are appropriately fastened with small staples. The pads are then placed in a sealable polyethylene bag before testing. The collagen film needs to be handled with tweezers.

[0108] 8. The test solution is a 0.9% NaCl solution.

[0109] "procedure" The evaluation is carried out in a stable laboratory environment set at 23°C and 50% humidity. The absorbent articles are conditioned in this same environment for 24 hours before testing. At least six identical absorbent articles are tested. The procedure is described for one of these absorbent articles.

[0110] The absorbent article 100 to be tested is stretched flat on a laboratory bench and cut along the side seams to remove the elastic, as shown in FIG. 6. The front waist portion 105 and the rear waist portion 106 of the absorbent article 100 are marked (the front portion faces the abdomen of the user). The front edge of the absorbent core 104 is identified, here corresponding to the second absorbent layer front edge 115a. Based on the total length (100%) of the absorbent core 104, a transverse reference line r is drawn on the top sheet 102 of the absorbent article 100 at a distance of 40% of the total length of the absorbent core 104 from the second absorbent layer front edge 115a. A first entry point P1 for liquid addition is marked 70 mm forward from the reference line r (centered in the transverse direction T of the absorbent article 1). A second point P2 is marked 65 mm back from the reference line r (centered in the transverse direction T) as a guide for the placement of the collagen pad for rewet measurement.

[0111] A 40x80 mm distance template is placed at the center of the reference line r of the absorbent core 104 (the length direction of the template is aligned with the longitudinal direction L of the absorbent article). The outer longitudinal leakage barrier of the distance template is lifted and the longitudinal side of the absorbent core 104 is folded up slightly (if there is no leakage barrier, the longitudinal edge of the absorbent member is lifted up along the side of the distance template). The leg blocks 4, 5 placed on the first plate 2 are pushed outwards to create a space, and the absorbent article 100 is placed in the fixture 1 with the front part 105 of the absorbent article 100 placed on the second plate 3 and the buttock template 6 removed from the fixture 1, as shown in Figure 7a. The reference line r is aligned with the center line C of each leg block 4, 5. The leg blocks 4, 5 are then pressed against the distance template to lock the blocks 4, 5 in this position. Carefully stretch the front 105 and rear 106 portions of the absorbent article 100 to remove folds and irregularities (wrinkles) (ensuring that the alignment between the leg blocks is not affected). Fix the absorbent article 100 with clamps 10 against the first and second plates 2, 3 as shown in Figures 7a, 7b. Place the buttock template 6 on the rear portion of the absorbent core 104 and push it forward to align it with the leg blocks 4, 5. The vertical wall portions 8a, 8c are angled inwards towards the intermediate wall portion 8b and are designed to fit tightly against the first block side walls 4b, 5b of the leg blocks 4, 5, respectively. Remove the distance template. Place a 10 kg metal weight 9 in the center of the buttock template 6 as shown in Figure 7b. Position the fluid outlet tube 12 connected to the fluid pump 11 above the fluid inlet point, i.e. at a 90° angle with respect to the plane of the absorbent article 100. The fluid outlet tube 12 is located 10 mm above the liquid inlet point P1.

[0112] A total of five 100 ml doses are then added to the absorbent article 100. A stopwatch is started as each dose is absorbed (i.e., no pooled liquid remains on the diaper surface) and after a 15 minute wait period the next dose is introduced.

[0113] Rewet is measured 10 minutes after the third, fourth and fifth administration. For this purpose, the 10 kg weight 9 and the buttock template 6 are removed. The bottom side of the buttock template 6 intended to face the absorbent article 100 is wiped dry and damp. The collagen pads (8 pieces) are weighed and placed on the absorbent article 100 with the length of the pad aligned with the longitudinal direction L of the absorbent article 100. The collagen pads are positioned by aligning the front edge of the collagen pad with a second point P2 (shown in FIG. 6) located 65 mm behind the reference line r. The length of the collagen pad is positioned away from the reference line r towards the rear part of the diaper 106. The buttock template 6 is then placed back on the collagen film and the 10 kg weight 9 is carefully lowered onto the center of the buttock template 6. After 30 seconds, the weight and buttock template 6 are removed and the collagen pad is weighed to measure liquid absorption (wet collagen weight minus dry collagen weight). The buttock template 6 and 10 kg weight 9 are then replaced and the dosing schedule continues. The Rewet 3 value is measured after the third dose, the Rewet 4 value is measured after the fourth dose and the Rewet 5 value is measured after the fifth dose. After the fifth dose, the absorbent article 1 is left in the fixture 101 under the pressure of the 10 kg weight for 6 hours and the Rewet 6 value is measured after 6 hours. The results are recalculated from grams to grams per square meter (gsm) for the area of ​​the collagen pad.

[0114] The entire procedure takes approximately 7.5 hours, equivalent to a full night's sleep.

[0115] "Test Results" Tests were conducted between the absorbent article of Example 1 and the absorbent article of Example 2 to measure the dryness of the topsheet under pressure, i.e., Rewet under pressure, as measured by the Rewet Under Pressure method disclosed herein.

[0116] Table 1 below shows the amount of absorbent material in the first and second absorbent layers of the Example 1 article and the Example 2 article.

[0117] The article of Example 2 is currently sold by Essity Hygiene and Health AB under the name Tena Pant Super. The absorbent article of Example 1 and the absorbent article of Example 2 have the same Rothwell, total capacity, value of 2010 ml. Both articles include an absorbent member having a first absorbent layer, a second absorbent layer, and a transfer layer disposed between the first upper absorbent layer and the topsheet. The dimensions of each layer are substantially the same between the article of Example 1 and the article of Example 2. In the absorbent article of Example 1, the transfer layer is disposed 60 mm toward the rear edge of the absorbent member compared to the article of Example 2. In the absorbent article of Example 1, the first absorbent layer is disposed 25 mm more toward the ear edge of the absorbent member compared to the article of Example 2.

[0118] [Table 1]

[0119] Table 2, set forth below, shows the test data from the absorbent article of Example 1 compared to the absorbent article of Example 2.

[0120] [Table 2] [Explanation of symbols]

[0121] 1 Fixture 2. First Plate 3. Second Plate 4, 5 Leg Block 4a, 5a rectangular side 4b, 5b First block side wall 4c, 5c Second block side wall 4d, 5d First rectangular side wall 4e, 5e Second rectangular side wall 6 Buttocks Template 7 Bottom plate 7a, 7b Longitudinal side 8 Template Wall 8a first side wall portion 8b Front wall section 8c Second side wall section 9. Weight 11 Liquid pump 12 Fluid outlet pipe 100 Absorbent articles 102 Top sheet 103 Back Seat 104 Absorbent Core 105 Front waist area 105a Front waist edge 106 Rear waist area 106a Center section, rear waist edge 106b Rear waist edge 107 Crotch area 108 Buttocks 109 First Lubricant Zone 114 First Absorption Layer 114a first absorbent layer front edge 114b first absorbent layer rear edge 115 Second Absorption Layer 115a second absorbent layer front edge 115b second absorbent layer rear edge 116, 117, 118, 119 Longitudinal lateral edges 120 Front Elastic Body 121 Rear Elastic Body 200 Belt-type absorbent articles 202 Topsheet 203 Back Seat 204 Absorbent Core 205 Front waist area 206 Rear waist area 207 Crotch area 208 Buttocks 209 First Lubricant Zone 210 Belt Lubrication Zone 216 Absorbent Pads 217 Belt d1 Front edge distance d2 Rear edge distance L Longitudinal T transverse direction C L center line r Reference Line P1 Liquid entry point P2 Second point

Claims

1. An absorbent article (100) comprising a liquid permeable topsheet (102), a backsheet (103) and an absorbent core (104) sandwiched between said topsheet (102) and said backsheet (103), the absorbent article (100) extending in a longitudinal direction (L) and a transverse direction (T) and defining, as viewed in the longitudinal direction, a front waist portion (105), a rear waist portion (106), a crotch portion (107) disposed between said rear waist portion and said front waist portion (105), and a hip portion (108) disposed between said crotch portion (107) and said rear waist portion (6), the topsheet (102) comprises a first lubricant zone (109) containing a lubricant, the first lubricant zone (109) being disposed over the buttocks portion (108); the absorbent core (104) comprises a first absorbent layer (114) and a second absorbent layer (115), the first absorbent layer (114) having a first absorbent layer front edge (114a) and a first absorbent layer rear edge (114b), the second absorbent layer (115) having a second absorbent layer front edge (115a) and a second absorbent layer rear edge (115b), the first absorbent layer (114) and the second absorbent layer (115) each having a size and shape in the plane of the absorbent article (100), the size and shape of the second absorbent layer (115) determining the size and shape of the absorbent core (104) in the plane of the absorbent article (100), the first absorbent layer (114) being shorter than the second absorbent layer (115) as viewed in the longitudinal direction (L) of the absorbent article (100); each of said first absorbent layer (114) and said second absorbent layer (115) comprises a superabsorbent polymer; The absorbent article (100) is characterized in that the first absorbent layer (114) is an upper absorbent layer and the second absorbent layer (115) is a lower absorbent layer, and the amount of superabsorbent polymer in the upper absorbent layer is 1.6 times greater than in the lower absorbent layer.

2. 2. The absorbent article (100) of claim 1, characterized in that the absorbent article (100) has a Rewet 1-6 value of less than or equal to 60 gsm (grams per square meter) as measured by the Rewet Under Pressure method disclosed herein.

3. 3. The absorbent article (100) of claim 1 or 2, characterized in that the absorbent article (100) has a Rewet 5 value of less than or equal to 30 gsm, as measured by the Rewet Under Pressure method disclosed herein.

4. 4. The absorbent article (100) of any one of claims 1 to 3, characterized in that the absorbent article (100) has a Rewet 4 value of less than or equal to 20 gsm, as measured by the Rewet Under Pressure method disclosed herein.

5. 5. The absorbent article (100) of any one of claims 1 to 4, characterized in that the absorbent article (100) has a Rewet 3 value of less than or equal to 10 gsm, as measured by the Rewet Under Pressure method disclosed herein.

6. The absorbent article (100) according to any one of claims 1 to 5, characterized in that the amount of lubricant in the first lubricant zone (109) is between 10 ppm and 10% by weight in the first lubricant zone (109) relative to the total weight of the topsheet.

7. The first lubricant zone (109) is 25 cm ２ The absorbent article (100) according to any one of claims 1 to 6, characterized in that it has a surface area within the above range.

8. The absorbent article (100) according to any one of the preceding claims, characterized in that said first lubricant zone (109) extends across the hip portion (108) and the rear waist portion (106).

9. The absorbent article (100) of any one of claims 1 to 8, wherein the topsheet (102) comprises a second lubricant zone (112), and the amount of lubricant in the first lubricant zone (109) is at least 25% greater than the amount of lubricant in the second lubricant zone (112).

10. 10. The absorbent article (100) of claim 9, characterized in that the second lubricant zone (112) is provided in the rear waist portion (106) of the user-facing side (110) of the absorbent article (100).

11. 2. The absorbent article (100) of claim 1, wherein the first absorbent layer front edge is positioned a front edge distance (d1) from the second absorbent layer front edge, the first absorbent layer rear edge (114b) is positioned a rear edge distance (d2) from the second absorbent layer rear edge (115b), and the ratio of the front edge distance (d1) to the rear edge distance (d2) is greater than or equal to 1.

5.

12. 2. The absorbent article of claim 1, wherein the absorbent article comprises a transfer layer disposed between the topsheet and the absorbent core, the transfer layer having a transfer layer front edge and a transfer layer rear edge, the transfer layer front edge being disposed a second front edge distance d3 from the second absorbent layer front edge and the transfer layer rear edge being disposed a second rear edge distance d4 from the second absorbent layer rear edge, and wherein a ratio of the second front edge distance d3 to the second rear edge distance d4 is greater than or equal to 1.

13. The absorbent article (100) according to any one of the preceding claims, characterized in that a rear waist portion (106) of said absorbent article (100) does not contain elastic threads.

Images