Disposable clothing

Abstract

To provide a disposable wearing article excellent in rash-proofing effect.SOLUTION: A disposable wearing article has a top sheet 30 that includes a skin contact area 30E for coming into contact with a wearer's skin. The top sheet 30 is made of a nonwoven fabric having a fineness of 1-3 dtex and a total weight of 10-30 g / m2. The skin contact area 30E has a glycerol-containing area 32 containing glycerol of 0.7-2.7 g / m2.SELECTED DRAWING: Figure 10

Description

[Technical Field]

[0001] This invention relates to disposable wearable items such as disposable diapers or sanitary napkins. [Background technology]

[0002] Disposable clothing, especially disposable diapers, often causes skin irritation, particularly rashes, in the wearer. Factors contributing to this include physical irritation to the wearer's skin (friction and stiffness) and a decrease in the skin's barrier function due to dryness.

[0003] It has been proposed to incorporate a waxy substance that exhibits a softening point higher than human body temperature into a top sheet made of nonwoven fabric, thereby reducing friction between the wearer's skin and the top sheet (see Patent Document 1).

[0004] Furthermore, it is known that a hydrophilic lotion may be applied to a top sheet made of nonwoven fabric to reduce friction, etc. (see Patent Document 2). Hydrophilic lotions are preferable because they can prevent the hardness of the waxy substance and the decrease in liquid permeability. In particular, hydrophilic lotions containing water are preferable to prevent skin dryness.

[0005] However, there is still room for improvement in terms of preventing diaper rash. For example, infants' skin is sensitive, so diapers worn by infants are prone to causing diaper rash. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 8-52175 [Patent Document 2] Special Publication No. 2010-526630 [Patent Document 3] Japanese Patent Publication No. 2002-509457 [Patent Document 4] Japanese Patent Publication No. 2019-170534

Summary of the Invention

Problems to be Solved by the Invention

[0007] Therefore, the main problems of the present invention are to provide a disposable wearable article having an excellent effect of preventing swelling, etc.

Means for Solving the Problems

[0008] The disposable wearable article that solves the above problems is as follows.

[0009] An absorbent material is built into the area including the groin, The absorbent material has a top sheet positioned on its outer surface, which includes a skin contact area that comes into contact with the wearer's skin, The aforementioned top sheet has a fineness of 1-2.5 dtex and a basis weight of 10-30 g / m². 2 It is a short-fiber nonwoven fabric with a thickness of 0.5 to 1.4 mm. The aforementioned short-fiber nonwoven fabric is a hydrophilic fiber nonwoven fabric in which a hydrophilic agent is coated onto hydrophobic resin fibers. The skin contact area has a glycerin-containing area that contains a hydrophilic lotion comprising 70-90% by weight of glycerin and 10-30% by weight of water. The viscosity of the hydrophilic lotion at a temperature of 20°C is 150-400 mPa·s. The glycerin-containing region is defined as having a glycerin content of 0.7 to 2.7 g / m². 2 The portion includes a portion having dimensions of 5 mm or more in the MD direction and 5 mm or more in the CD direction, The glycerin content in the skin contact area is 0.7 to 2.7 g / m². 2 The area ratio of that portion is 3% or more. The glycerin content in the glycerin-containing region is 0.7 to 2.7 g / m². 2 The average friction coefficient MIU for that section is 0.2 to 0.4. The glycerin content in the glycerin-containing region is 0.7 to 2.7 g / m². 2 The surface moisture content of that part is 4-10%. A disposable wearable article characterized by the above.

[0010] (Function and Effect) This disposable wearable item is characterized by its combination of glycerin and a nonwoven fabric top sheet, specifically by the combination of the glycerin content per unit area and the use of a nonwoven fabric with fine fibers in the top sheet. The fineness of the fibers in such a top sheet contributes to reducing surface friction, and combined with the friction-reducing effect of glycerin, the overall friction reduction effect is improved. Furthermore, the fineness of the fibers improves the retention of glycerin, which also enhances the friction reduction effect. In addition, the glycerin contained in the top sheet transfers to the wearer's skin, moisturizing (preventing dryness) the wearer's skin (especially by penetrating the stratum corneum). In particular, a surface moisture content of 4-8% allows the garment to adequately moisturize the wearer's skin and prevent dryness. Therefore, this disposable wearable item achieves a high degree of balance between reducing physical irritation to the wearer's skin and moisturizing the wearer's skin, and is particularly effective in preventing skin irritation. Furthermore, by ensuring that the dimensions and area ratio of the glycerin-containing region are within the above range, the product exhibits particularly excellent physical irritation reduction and skin moisturizing effects on the wearer. Furthermore, while nonwoven fabrics made of hydrophobic resin fibers are preferable for the top sheet due to their low cost, they have poor glycerin retention properties in that form. Therefore, in this case, it is preferable to use a nonwoven fabric made of hydrophilic fibers with a hydrophilizing agent to improve the glycerin retention properties of the nonwoven fabric. The term "skin contact area" refers to the area exposed to the surface of an item when it is unfolded.

[0011] <Second aspect> The top sheet is a perforated nonwoven fabric having a pore arrangement region in which holes penetrating from the front to the back are arranged in a predetermined pattern. The skin contact area comprises the glycerin-containing area, the pore arrangement area, and the overlapping area where the glycerin-containing area and the pore arrangement area overlap. The top sheet is bonded to a backing member located on the back side of the top sheet via a hydrophobic hot-melt adhesive, at least over the entire pore arrangement region. A disposable wearable article of the first type.

[0012]

[0013] <Third aspect> The glycerin-containing region is continuous in the front-to-back direction throughout the entire length of the product, with multiple portions having different glycerin content connected in the front-to-back direction. The total glycerin content of the aforementioned glycerin-containing region is 0.7 g / m². 2 less Disposable wearable articles in the first or second form.

[0014]

[0015] <Fourth aspect> The amount of IL-1α secreted, measured by contacting the glycerin-containing region of the top sheet with a three-dimensional cultured skin model, is less than or equal to half the amount of IL-1α secreted when the top sheet differs only in that it does not contain glycerin. The amount of filaggrin measured by contacting the glycerin-containing region of the top sheet with a three-dimensional cultured skin model is greater than the amount of filaggrin measured in the case of a top sheet that differs only in that it does not contain glycerin. A disposable wearable article in any one of the three forms described above.

[0016] (Effects and Benefits) IL-1α (interleukin-1α) is an inflammatory cytokine produced in the skin when exposed to irritants that cause skin irritation (redness). In other words, a low level of IL-1α secretion, as measured by contact with a three-dimensional cultured skin model, as described in this embodiment, results in superior ability to prevent skin irritation. The method for measuring IL-1α secretion is described below. Also, Filaggrin is one of the main components of each layer of the skin and greatly affects the strength and flexibility of the stratum corneum. It is known that when filaggrin levels are low, keratinocytes become more prone to peeling, and transepidermal water loss (TEWL) also increases. Furthermore, filaggrin is broken down into natural moisturizing factors (NMF), which play a role in moisturizing the stratum corneum and maintaining its pH. In other words, a high amount of filaggrin, as measured by contact with a three-dimensional cultured skin model, as described in this embodiment, results in superior ability to prevent rashes. The method for measuring filaggrin levels is described below.

[0017]

[0018] [Effects of the Invention]

[0019] According to the present invention, advantages such as superior effectiveness in preventing skin irritation are obtained. [Brief explanation of the drawing]

[0020] [Figure 1] This is a plan view showing the inner surface of a tape-type disposable diaper in its unfolded state. [Figure 2] This is a plan view showing the outer surface of a tape-type disposable diaper in its unfolded state. [Figure 3] This is a cross-sectional view of section 6-6 in Figure 1. [Figure 4] This is a cross-sectional view of section 7-7 in Figure 1. [Figure 5] (a) Section 8-8 of Figure 1, (b) Section 9-9 of Figure 1, and (c) Section 10-10 of Figure 1. [Figure 6] This is a plan view showing various examples of hole arrangement patterns in perforated nonwoven fabrics. [Figure 7] This is a plan view showing an example of a perforated nonwoven fabric pore arrangement pattern (Moroccan pattern). [Figure 8]This is a plan view showing an example of a pore arrangement pattern (chain pattern) in a perforated nonwoven fabric. [Figure 9] This is a cross-sectional view of the perforated portion of a perforated nonwoven fabric. [Figure 10] This is a plan view showing the inner surface of a tape-type disposable diaper in its unfolded state. [Figure 11] This is a plan view showing the inner surface of a tape-type disposable diaper in its unfolded state. [Figure 12] This is a plan view illustrating the test specimen. [Figure 13] This graph shows the measurement results of the stratum corneum moisture content. [Figure 14] This graph shows the results of transepidermal water loss (TEWL) measurements. [Figure 15] This graph shows the results of measuring IL-1α secretion levels. [Figure 16] This is a photograph showing the results of observations on filaggrin levels. [Modes for carrying out the invention]

[0021] Figures 1 to 5 show a tape-type disposable diaper as an example of a disposable wearable item. In the figures, the symbol X indicates the total width of the diaper excluding the connecting tape 13, and the symbol L indicates the total length of the diaper. The dotted pattern in the cross-sectional view indicates the adhesive used as a joining means for joining the various components. The hot melt adhesive can be applied by known methods such as slot coating, continuous linear or dotted bead coating, spiral, Z-shaped, or wavy spray coating, or pattern coating (transfer of hot melt adhesive using a relief printing method). Alternatively, or in conjunction with these methods, the hot melt adhesive can be applied to the outer surface of the elastic member to fix it to the adjacent member. Examples of hot melt adhesives include EVA-based, adhesive rubber-based (elastomer-based), olefin-based, and polyester / polyamide-based adhesives, but they can be used without particular limitation. As a joining means for joining the various components, methods of material welding such as heat sealing or ultrasonic sealing can also be used.

[0022] Furthermore, in the following description, known nonwoven fabrics can be used as appropriate depending on the part and purpose. The constituent fibers of the nonwoven fabric can be selected without particular limitation, including synthetic fibers such as polyethylene or polypropylene (olefin-based), polyester-based, and polyamide-based (including single-component fibers as well as composite fibers such as core-sheaths), as well as regenerated fibers such as rayon and cupro, and natural fibers such as cotton, and these can also be used in mixtures. To increase the flexibility of the nonwoven fabric, it is preferable to use crimped fibers as constituent fibers. In addition, the constituent fibers of the nonwoven fabric may be hydrophilic fibers (including those made hydrophilic by a hydrophilizing agent), hydrophobic fibers, or water-repellent fibers (including those made water-repellent by a water-repellent agent). Furthermore, nonwoven fabrics are generally classified according to fiber length, sheet formation method, fiber bonding method, and lamination structure into short fiber nonwoven fabrics, long fiber nonwoven fabrics, spunbond nonwoven fabrics, meltblown nonwoven fabrics, spunlace nonwoven fabrics, thermal bond (air-through) nonwoven fabrics, needle punch nonwoven fabrics, point bond nonwoven fabrics, and laminated nonwoven fabrics (including SSS nonwoven fabrics, which consist of laminated identical or similar nonwoven fabric layers, as well as SMS nonwoven fabrics and SMMS nonwoven fabrics, which consist of laminated different nonwoven fabric layers with meltblown layers sandwiched between spunbond layers). Any of these nonwoven fabrics can be used. Laminated nonwoven fabrics refer to those manufactured as a single, integrated nonwoven fabric including all layers, with fiber bonding applied to all layers, and do not include those made by bonding multiple separately manufactured nonwoven fabrics together using bonding means such as hot melt adhesive.

[0023] This tape-type disposable diaper has a ventral portion F extending forward from the center of the front-to-back LD and a dorsal portion B extending backward from the center of the front-to-back LD. The shape of this tape-type disposable diaper has a crotch portion M extending from the front of the center of the product in the front-to-back direction to the rear of the center of the product in the front-to-back direction, front wings 80 protruding on both sides at a position away from the front of the center of the product in the front-to-back direction, and rear wings 81 protruding on both sides at a position away from the rear of the center of the product in the front-to-back direction. Furthermore, this tape-type disposable diaper has an absorbent material 56 built into the area including the crotch, a liquid-permeable top sheet 30 covering the front side of the absorbent material 56, a liquid-impermeable sheet 11 covering the back side of the absorbent material 56, and an outer nonwoven fabric 12 covering the back side of the liquid-impermeable sheet 11 and forming the outer surface of the product.

[0024] The following describes the materials and distinctive features of each part in order. (Absorbent) The absorbent body 56 is the part that absorbs and retains excretory fluid and can be formed from a fiber aggregate. This fiber aggregate can be made by stacking short fibers such as cotton pulp or synthetic fibers, or by opening filament aggregates obtained by unfolding tows (fiber bundles) of synthetic fibers such as cellulose acetate as needed. For fiber basis weight, when stacking cotton pulp or short fibers, for example, 100-300 g / m² is used. 2 It can be set to a certain extent, and in the case of filament aggregates, for example, 30-120 g / m². 2 The fineness can be set to a certain degree. In the case of synthetic fibers, the fineness is, for example, 1 to 16 dtex, preferably 1 to 10 dtex, and more preferably 1 to 5 dtex.

[0025] The planar shape of the absorber 56 can be determined as appropriate; it can be rectangular, or it can be a shape that is constricted so that the middle of the front-to-back LD follows the shape of the legs.

[0026] (Highly absorbent polymer particles) The absorbent material 56 may contain superabsorbent polymer particles in part or in whole. Superabsorbent polymer particles include not only "particles" but also "powder." Superabsorbent polymer particles used in this type of absorbent article can be used as they are. The particle size of the superabsorbent polymer particles is not particularly limited, but it is desirable that, for example, when sieving is performed using a 500 μm standard sieve (JIS Z8801-1:2006) (shaking for 5 minutes), and the particles that fall below the sieve are then sieved using a 180 μm standard sieve (JIS Z8801-1:2006) (shaking for 5 minutes), the proportion of particles remaining on the 500 μm standard sieve is 30% by weight or less, and the proportion of particles remaining on the 180 μm standard sieve is 60% by weight or more.

[0027] While there are no particular limitations on the material used for the superabsorbent polymer particles, those with a water absorption capacity of 40 g / g or more are preferred. Examples of superabsorbent polymer particles include starch-based, cellulose-based, and synthetic polymer-based materials. Starch-acrylic acid (salt) graft copolymers, saponified starch-acrylonitrile copolymers, crosslinked sodium carboxymethylcellulose, and acrylic acid (salt) polymers can be used. While the commonly used granular form is preferred for the superabsorbent polymer particles, other forms can also be used.

[0028] As superabsorbent polymer particles, those with a water absorption rate of 70 seconds or less, and particularly 40 seconds or less, are preferably used. If the water absorption rate is too slow, the liquid supplied into the absorbent material 56 is likely to flow back out of the absorbent material 56, a phenomenon known as backflow.

[0029] Furthermore, as the superabsorbent polymer particles, those with a gel strength of 1000 Pa or more are preferably used. This effectively suppresses the sticky feeling after liquid absorption, even when a bulky absorbent material 56 is used.

[0030] The basis weight of the superabsorbent polymer particles can be appropriately determined according to the absorption amount required for the use of the absorber 56. Therefore, although it cannot be generally stated, in a normal case, it can be set to 50 to 350 g / m 2 can be used.

[0031] (Packaging sheet) In order to prevent the superabsorbent polymer particles from escaping or to enhance the shape retention of the absorber 56, the absorber 56 can be incorporated as an absorption element 50 wrapped with a packaging sheet 58. As the packaging sheet 58, tissue paper, particularly crepe paper, non-woven fabric, poly-laminated non-woven fabric, a sheet with small holes, etc. can be used. However, a sheet that does not allow the superabsorbent polymer particles to escape is desirable. When using a non-woven fabric instead of crepe paper, a hydrophilic SMMS (spunbond / meltblown / meltblown / spunbond) non-woven fabric is particularly suitable, and its material can use polypropylene, polyethylene / polypropylene, etc. The fiber basis weight is 5 to 40 g / m 2 , particularly 10 to 30 g / m 2 is desirable.

[0032] As shown in FIG. 3, this packaging sheet 58 may be structured to wrap the entire absorber 56 with a single sheet, or may wrap the entire absorber 56 with a plurality of sheets such as two upper and lower sheets. The packaging sheet 58 can also be omitted.

[0033] (Top sheet) The top sheet 30 extends from the front end to the rear end of the product in the front-rear direction and extends laterally beyond the absorber 56 in the width direction WD. However, for example, when the starting point of the rising gathers 60 described later is located closer to the center in the width direction WD than the side edge of the absorber 56, etc., appropriate deformations such as shortening the width of the top sheet 30 to be shorter than the full width of the absorber 56 can be made as needed.

[0034] The top sheet 30 has a skin contact area 30E that comes into contact with the wearer's skin, and is preferably made of a nonwoven fabric from the viewpoint of liquid permeability and skin feel. Various nonwoven fabrics can be used for the top sheet 30, but considering cushioning, flexibility, and permeability of loose stools (watery or muddy stools), a short-fiber nonwoven fabric such as an air-through nonwoven fabric is preferred over a long-fiber (continuous-fiber) nonwoven fabric, and is usually a fineness of 1 to 10 dtex and a basis weight of 10 to 30 g / m². 2 A short-fiber nonwoven fabric with a thickness of approximately 0.4 to 1.4 mm is preferred. The fiber length of the short-fiber nonwoven fabric is not particularly limited, but it is preferably approximately 0.5 to 1.0 mm.

[0035] The top sheet 30 is particularly preferably a perforated nonwoven fabric having a hole arrangement region in which holes 14 penetrating from front to back are arranged in a predetermined pattern. The shape, dimensions, arrangement pattern, etc. of the holes 14 can be determined as appropriate. Note that in Figure 1, for the sake of clarity, the holes 14 are shown only in a part D of the top sheet 30, but this does not represent the hole arrangement region.

[0036] The pore arrangement region can be limited to only the intermediate region in the front-to-back direction LD of the top sheet 30, or only the intermediate region in the width direction WD of the top sheet 30 (it may also have a portion without pores 14). Alternatively, the pore arrangement region can encompass the entire top sheet 30. In other words, as long as the pore arrangement region is provided in the skin contact region 30E, it may extend to other regions (for example, the region where the gather sheet 62 is bonded on both sides of the width direction WD).

[0037] The planar shape (opening shape) of each hole 14 can be determined as appropriate. In addition to the elongated hole shape shown in Figures 6(a) and (b), the holes 14 can be any shape, such as a perfect circle as shown in Figures 6(c), (e), and (f), Figures 7 and 8, an ellipse as shown in Figure 6(d), a triangle, a rectangle, a rhombus or other polygon, a star shape, a cloud shape, etc. Although not shown, holes 14 of different shapes may be mixed together. The dimensions of each hole 14 are not particularly limited, but the front-to-back dimension (dimension of the longest part) 14L is preferably 0.5 to 2.0 mm, particularly 0.5 to 2.0 mm, and the width dimension (dimension of the longest part) 14W is preferably 0.5 to 2.0 mm, particularly 0.5 to 1.0 mm. When the shape of the hole 14 is elongated in the front-to-back direction, such as a long hole, ellipse, rectangle, or rhombus (a shape in which the total length in one direction is longer than the total length in the direction perpendicular to it), it is preferable that the dimension in the front-to-back direction is 1.2 to 2.5 times the dimension in the width direction perpendicular to it. Also, when the shape of the hole 14 is elongated in one direction, it is preferable that the longitudinal direction of the hole 14 is the MD direction of the nonwoven fabric, but it may also be the CD direction or an oblique direction inclined to these. Note that the MD direction of the perforated nonwoven fabric forming the top sheet 30 is often equal to the front-to-back direction LD.

[0038] The area and area ratio of the holes 14 in the hole arrangement region can be determined as appropriate, but the area should be between 0.25 and 4.00 mm². 2 It is preferable that the area ratio be around 0.1 to 10%.

[0039] The arrangement pattern of the holes 14 can be determined as appropriate. For example, as shown in Figures 6(a), (c), and (d), it is preferable that the arrangement pattern of the holes 14 is a matrix in which rows of holes 14 arranged linearly at predetermined intervals in the front-to-back direction LD are repeated with predetermined intervals in the width direction WD. In this case, as shown in Figures 6(a) and (d), the arrangement can be such that the interval 14y of the holes 14 in the front-to-back direction LD is shorter than the interval 14x of the holes 14 in the width direction WD, as shown in Figure 6(c), or the arrangement can be such that the interval 14y of the holes 14 in the front-to-back direction LD is approximately equal to the interval 14x of the holes 14 in the width direction WD, as shown in Figures 6(b) and (e). Furthermore, as shown in Figures 6(b) and (e) and Figure 7, the rows 95 of holes arranged linearly at predetermined intervals in the front-to-back direction LD can be arranged with a gap 14d in the width direction WD and with the positions in the front-to-back direction LD shifted. The example shown in Figures 6(a) and 6(b) is a so-called staggered (hexagonal lattice) arrangement in which the holes 14 are arranged alternately in adjacent rows 95 of holes.

[0040] The spacing 14y in the front-to-back direction and the spacing 14x in the width direction of the holes 14 may be constant or vary. These can be determined as appropriate, but for example, the spacing 14y in the front-to-back direction of the holes 14 can be 0.9 to 8.0 mm, particularly 1.0 to 3.0 mm, and the spacing 14x in the width direction of the holes 14 can be 2.0 to 10 mm, particularly 3.0 to 5.0 mm.

[0041] Furthermore, as shown in 6(f) and Figure 7, the arrangement pattern of the holes 14 can be such that groups 90 of holes 14 are arranged in a single wave pattern 91,92 following the front-to-back direction LD, spaced apart in the width direction WD, and arranged in the same or different phases. In the example pattern shown in Figure 7, the wave patterns of adjacent groups 90 of holes 14 in the width direction WD are in opposite phases, and the imaginary lines connecting the holes 14 form a Moroccan pattern (vertical wave pattern). In Figure 7, reference numeral 94 indicates a unit arrangement portion, and reference numeral 94W ​​indicates its width direction WD dimension. Also, as shown in Figure 8, groups 90 of holes 14 are arranged at intervals to form a chain-like pattern following the front-to-back direction LD, and are spaced apart in the width direction WD. Here, "groups 90 of holes 14 are spaced apart in the width direction WD" means that between adjacent groups 90 of holes 14 in the width direction WD, there is a continuous, straight, non-perforated portion 93 along the front-to-back direction LD.

[0042] The cross-sectional shape of the hole 14 is not particularly limited. For example, the hole 14 may be a punched-type hole whose periphery is formed by the cut ends of fibers, or it may be a non-punched-type hole (with a high fiber density at the edge) in which there are almost no cut ends of fibers at the periphery of the hole 14, and it is formed by inserting a pin between the fibers and pushing it open. The punched-type hole may have a diameter that decreases towards the middle of the thickness direction, as shown in Figure 9(d), or it may decrease towards one side of the thickness direction, although this is not shown.

[0043] Non-punched holes 14 are characterized by a decrease in diameter as the pin insertion side is moved away from the pin insertion side. This includes holes where the diameter of the hole 14 continues to decrease throughout the thickness direction of the nonwoven fabric layer, as well as holes where the decrease in diameter of the hole 14 almost disappears in the middle of the thickness direction. Such non-punched holes include those in which, as shown in Figures 9(a) and (c), protrusions (burrs) 14e are formed on the edge of the hole 14 on the side opposite to the pin insertion side, with fibers pushed out to the opposite side, and no protrusions 14e are formed on the pin insertion side, as shown in Figure 9(b). Furthermore, the former type of hole 14 includes those in which the protrusion height 14h of the protrusion 14e is substantially uniform, as shown in Figure 9(a), and those in which the protrusion 14e has an opposing portion with the highest protrusion height 14i and an opposing portion in a direction perpendicular to it, where the lowest protrusion height 14j is the opposing portion, as shown in Figure 9(c). It is desirable that the protrusion 14e is cylindrical and continuous in the circumferential direction of the hole 14, but the protrusion 14e of some or all of the holes 14 may be formed only in a part of the circumferential direction of the hole 14. The protrusion heights 14h, 14i, and 14j (apparent heights in an unpressurized state measured using an optical microscope) are preferably about 0.2 to 1.2 mm. Also, it is preferable that the highest protrusion height 14i of the protrusion 14e is about 1.1 to 1.4 times the lowest protrusion height 14j. The protrusion height of the protrusion 14e may vary in the circumferential direction of the hole 14.

[0044] For example, when a hole 14 with a shape elongated in one direction, as shown in Figures 6(a), (b), and (d), is formed by inserting a pin, the fibers at the edge of the hole 14 are pushed outward or vertically, forming a protruding portion (burr) 14e where the protruding height 14i of the opposing portion in the longitudinal direction of the hole 14 is higher than the protruding height 14j of the opposing portion in the direction perpendicular to the longitudinal direction. The fiber density of the protruding portion 14e of the hole 14 may be lower than that of the surrounding portion, but it is preferable that it is about the same or higher.

[0045] In particular, the perforated nonwoven fabric has a fineness of 0.1 to 5.0 dtex (more preferably 1.0 to 3.0 dtex) and a basis weight of 15 to 20 g / m². 2 (more preferably 15-18 g / m²) 2 ), in the case of a long-fiber nonwoven fabric with a thickness of 0.3 to 0.8 mm (more preferably 0.3 to 0.6 mm), when a hole 14 is formed by inserting a pin, the protrusion 14e formed at the edge of the hole 14 becomes lower. More specifically, in the case of a long-fiber nonwoven fabric within the above-mentioned specific range, when a pin insertion hole is formed, the fibers are not easily pushed out in the thickness direction. This is because the fibers to which force is applied by inserting the pin are intertwined and continuous throughout the entire nonwoven fabric (continuous fibers), and the movement of fibers in the part to which force is applied by inserting the pin is suppressed by the part connected to the outside. Furthermore, since the long-fiber nonwoven fabric within the above-mentioned specific range basically has a moderately low fiber density, the movement of fibers in the direction perpendicular to the thickness direction is relatively easy. As a result, when a pin is inserted into the long-fiber nonwoven fabric within the specified range described above to form a hole 14 of the specified dimensions, the fibers near the pin are pushed out radially from the direction of pin insertion and move toward the pin exit side. Therefore, although a protrusion 14e is formed, its height is reduced. Furthermore, a high-density area is formed at the edge of the hole 14, where the fiber density is higher than the surrounding area. This high-density area has the advantage of making the shadow between the hole 14 and its surroundings stronger, thus improving the visibility of the hole 14.

[0046] (Intermediate sheet) To quickly transfer the liquid that has permeated through the top sheet 30 to the absorbent material 56, an intermediate sheet (also called a "second sheet") 40 can be provided, which has a faster liquid permeation rate than the top sheet 30. This intermediate sheet 40 is intended to quickly transfer the liquid to the absorbent material 56, enhance the absorption performance of the absorbent material 56, and prevent the "backflow" phenomenon of the absorbed liquid from the absorbent material 56. The intermediate sheet 40 can also be omitted.

[0047] As the intermediate sheet 40, a liquid-permeable sheet such as a nonwoven fabric can be used. Air-through nonwoven fabric is particularly preferred as the intermediate sheet 40 because of its bulkiness. For the air-through nonwoven fabric, a core-sheath composite fiber structure is preferred. In this case, the resin used for the core may be polypropylene (PP), but highly rigid polyester (PET) is preferred. The basis weight is 17-80 g / m². 2 Preferably, 18-60 g / m 2 This is more preferable. The thickness of the raw fibers for the nonwoven fabric is preferably 2.0 to 10 dtex. In order to make the nonwoven fabric bulky, it is also preferable to use off-center fibers without a core in the center, hollow fibers, or off-center and hollow fibers as all or part of the mixed fibers of the raw fibers.

[0048] In the illustrated example, the intermediate sheet 40 is shorter than the width of the absorbent material 56 and positioned in the center, but it may also be provided across the entire width. Furthermore, the intermediate sheet 40 may be provided across the entire length of the diaper, or it may be provided only in the intermediate portion of the anterior-posterior direction LD including the excretion area, as shown in the illustrated example.

[0049] (Liquid-impermeable sheet) The liquid-impermeable sheet 11 is not particularly limited, but it is preferable that it has moisture permeability. As the liquid-impermeable sheet 11, for example, a microporous sheet obtained by kneading an inorganic filler into an olefin resin such as polyethylene or polypropylene, forming a sheet, and then stretching it in a uniaxial or biaxial direction can be suitably used. In addition, as the liquid-impermeable sheet 11, a nonwoven fabric with enhanced waterproofing properties can also be used.

[0050] It is desirable that the liquid-impermeable sheet 11 extends over the same or a wider area in the front-to-back direction LD and the width direction WD as the absorber 56, but if necessary, such as when other water-blocking means exist, the sheet may be constructed so as not to cover the edges of the absorber 56 in the front-to-back direction LD and the width direction WD.

[0051] (Outer nonwoven fabric) The outer nonwoven fabric 12 covers the entire back side of the liquid-impermeable sheet 11, giving the product's outer surface a cloth-like appearance. The fiber weight of the outer nonwoven fabric 12 is 10-50 g / m². 2 Especially 15-30g / m 2 While this is preferable, it is not limited to this. The outer nonwoven fabric 12 can be omitted, in which case the liquid-impermeable sheet 11 can be extended to the side edge of the product.

[0052] (Rising Gather) To prevent excrement from moving laterally along the top sheet 30 and thus prevent so-called lateral leakage, it is preferable that upward-rising gathers 60 that rise towards the wearer's skin are provided on both sides of the width direction WD of the surface. Of course, the upward-rising gathers 60 can be omitted.

[0053] When adopting the rise-up gather 60, its structure is not particularly limited, and any known structure can be adopted. The rise-up gather 60 in the illustrated example consists of a gather sheet 62 that is substantially continuous in the width direction WD, and an elongated gather elastic member 63 that is fixed to the gather sheet 62 in an extended state along the front-rear direction LD. A water-repellent nonwoven fabric can be used for the gather sheet 62, and elastic thread or the like can be used for the gather elastic member 63. Multiple gather elastic members 63 can be provided as shown in Figures 1 and 2, or one can be provided for each.

[0054] The inner surface of the gathered sheet 62 has a joining start end in the width direction WD on the side of the top sheet 30, and the portion 65 extending outward in the width direction from this joining start end is joined to the inner surface of each side flap SF, that is, in the illustrated example, to the side of the liquid-impermeable sheet 11 and the side of the outer nonwoven fabric 12 located outside it in the width direction, using a hot melt adhesive or the like.

[0055] In the leg area, the portion 66 in the width direction from the starting end of the rise-up gather 60 towards the center is fixed on the top sheet 30 at both ends 67 in the front-to-back direction of the product, but the portion in between is an unfixed free portion 68, and this free portion 68 rises up due to the contraction force of the gather elastic member 63 and comes into close contact with the body surface.

[0056] (End flaps, side flaps) The illustrated tape-type disposable diaper has a pair of end flaps EF that do not have an absorbent material 56 and extend to the front and rear sides of the absorbent material 56, respectively, and a pair of side flaps SF that do not have an absorbent material 56 and extend laterally from both side edges of the absorbent material 56. The side flaps SF may be made of a main sheet (such as an outer nonwoven fabric 12) that is continuous with the portion having the absorbent material 56, as shown in the illustrated example, or they may be formed by attaching other materials.

[0057] (Flat gathering) Each side flap SF has a side elastic member 64, made of an elongated elastic material such as elastic thread, fixed to it in an extended state along the front-to-back direction LD, thereby forming a flat gather around the leg portion of each side flap SF. As shown in the illustrated example, the side elastic member 64 can be provided between the gather sheet 62 and the liquid-impermeable sheet 11 on the outside in the width direction near the starting end of the joint portion of the gather sheet 62, or it can be provided between the liquid-impermeable sheet 11 and the outer nonwoven fabric 12 in the side flap SF. As shown in the illustrated example, multiple side elastic members 64 can be provided on each side, or only one can be provided on each side. Of course, the side elastic member 64 (flat gather) can also be omitted.

[0058] The flat gather is the part where the contraction force of the side elastic member 64 acts (in the figure, the part where the side elastic member 64 is shown). Therefore, in addition to the form in which the side elastic member 64 exists only in the flat gather area, there is also a structure in which the side elastic member 64 exists in front of the flat gather, behind it, or on both sides thereof, but the side elastic member 64 is cut into many small pieces in places other than the flat gather area, or is not fixed to the sheet sandwiching the side elastic member 64, or both, so that the contraction force does not act on the parts other than the flat gather (essentially equivalent to not having the side elastic member 64), and the contraction force of the side elastic member 64 acts only on the flat gather area.

[0059] (Front wing) This tape-type disposable diaper has front wings 80 that protrude on both the left and right sides, positioned slightly forward of the center of the product in the front-to-back direction. The front wings 80 can be omitted (i.e., the width of the product does not change from the narrowest part to the front edge).

[0060] The widthwise WD dimension of the front wing 80 can be determined as appropriate, but for example, it can be 5-20% (especially 7-15%) of the total length Y of the article. The widthwise WD dimension of the front wing 80 can be approximately the same as the widthwise WD dimension of the rear wing 81, which will be described later.

[0061] (Rear wing) This tape-type disposable diaper has rear wings 81 that protrude on both the left and right sides, located at a position away from the center of the product in the front-to-back direction.

[0062] The widthwise dimension (WD) of the rear wing 81 can be determined as appropriate, and can be the same as the widthwise dimension of the front wing 80, or it can be smaller or larger than the widthwise dimension of the front wing 80.

[0063] (middle part) Both side edges 15 of the product between the front wing 80 and the rear wing 81 may have substantially straight portions passing through a width range of ±5 mm in a direction perpendicular to a direction where the acute-side intersection angle with respect to the longitudinal direction LD is less than ±2 degrees. Both side edges 15 of the product between the front wing 80 and the rear wing 81 may be wavy or arc-shaped (not shown), or they may be straight as in the illustrated example.

[0064] (Wing formation) As shown in the illustrated example, by cutting a concave shape into the side of the side flap SF, the entire concave edge can be formed from the lower edge of the front wing 80, through both side edges 15 of the product between the front wing 80 and the rear wing 81, to the lower edge of the rear wing 81. In this case, the laminated structure of the front wing 80 and the rear wing 81 is determined by the laminated structure of the side flap SF, and in the illustrated example, the front wing 80 and the rear wing 81 are formed by the gathered sheet 62 and the outer nonwoven fabric 12. Although not shown, a front extension sheet may be provided that protrudes laterally from the side flap SF, and the entire front wing 80 or a part of the tip side may be formed by the front extension sheet. Similarly, a rear extension sheet may be provided that protrudes laterally from the side flap SF, and the entire rear wing 81 or a part of the tip side may be formed by the rear extension sheet. Various nonwoven fabrics can be used as the front extension sheet and the rear extension sheet.

[0065] (Connection part) The rear wing 81 is provided with a connecting portion 13A that is detachably connected to the ventral portion F when worn. That is, when wearing, both sides of the rear wing 81 are brought to the wearer's ventral side, and the connecting portion 13A of the rear wing 81 is connected to the outer surface of the ventral portion F. The connecting portion 13A may be provided with a hook material (male part) of a mechanical fastener (hook-and-loop fastener), or it may be provided with an adhesive layer. The hook material has a number of engaging protrusions on its connecting surface, and any known shape of engaging protrusions can be adopted, such as L-shape, J-shape, mushroom shape, T-shape, double J-shape (a shape in which J-shapes are joined back to back).

[0066] The connecting portion 13A can be directly attached to the rear wing 81, or, as shown in the illustrated example, a connecting tape 13 having the connecting portion 13A can be attached to the rear wing 81. The structure of the connecting tape 13 is not particularly limited, but in the illustrated example, it has a tape attachment portion 13C fixed to the side flap SF, a tape body portion 13B protruding from the tape attachment portion 13C, and a connecting portion 13A provided in the middle of the width direction WD of the tape body portion 13B, with the tip side of the connecting portion 13A being a gripping portion. Nonwoven fabric, plastic film, poly-laminated nonwoven fabric, paper, or composite materials thereof can be used as the sheet material forming from the tape attachment portion 13C to the tape body portion 13B.

[0067] The connection points of the connecting portion 13A on the outer surface of the ventral portion F can be determined as appropriate. The connection points may be limited to the main body portion located between the left and right front wings 80, or they may extend from the side of the main body portion to the base end of the front wings 80. It is preferable that these connection points facilitate the connection of the connecting portion 13A. For example, if the connecting portion 13A is the hook (male) of a mechanical fastener (hook-and-loop fastener), the connection points on the outer surface of the ventral portion F may be formed from the loop (female) 24 of the mechanical fastener or a nonwoven fabric. As the loop 24, a plastic film with loop threads sewn onto it is known, but a long-fiber nonwoven fabric with a fiber continuity direction in the width direction WD (fineness 2.0-4.0 dtex, basis weight 20-50 g / m²) is also preferred. 2 From the viewpoint of breathability and flexibility, a spunbond nonwoven fabric (such as one with a thickness of approximately 0.3 to 0.5 mm) is provided with welded sections in which fibers are intermittently welded to each other at least in the width direction WD. As shown in the illustrated example, if the area on the outer surface of the ventral portion F including the connection point is formed of the outer nonwoven fabric 12, the hook material can be connected to the outer nonwoven fabric 12 without adding anything. If necessary, the loop material 24 may be attached only to the connection point on the outer surface of the ventral portion F. Also, if the connection part 13A is an adhesive layer, a plastic film with a smooth surface that is highly adhesive can be attached to the connection point on the outer surface of the ventral portion F.

[0068] (Securing the top sheet) Preferably, the top sheet 30 is bonded to the backing member located on the back of the top sheet 30 via a hydrophobic hot-melt adhesive 31. Alternatively, or in conjunction with this, the top sheet 30 may be joined to the backing member located on the back of the top sheet 30 by welding at least one of the top sheet 30 and the backing member located on the back of the top sheet 30. The fixing area of ​​the top sheet 30 may extend to other areas (e.g., the entire top sheet 30) or only to the hole arrangement area, as long as it covers at least the entire hole arrangement area. In the illustrated example, the backing member is an intermediate sheet 40, a packaging sheet 58, and a liquid-impermeable sheet 11, but is not limited to these.

[0069] As the hydrophobic hot melt adhesive 31, EVA-based, olefin-based, polyester / polyamide-based adhesives can be used, and adhesive rubber-based (elastomer-based) adhesives can be particularly preferred.

[0070] The amount of hydrophobic hot melt adhesive 31 applied can be determined as appropriate, but typically it is 0.1 to 10 g / m². 2 It can be set to a certain extent. In particular, the application amount of the hydrophobic hot melt adhesive 31 is 0.5 to 5 g / m². 2 While this is preferable because it suppresses the overflow of the hot melt adhesive 31 from the holes 14, it is desirable to combine it with measures such as improving the glycerin application pattern, as this makes adhesion inhibition by glycerin, as described later, more likely to occur. The application pattern of the hydrophobic hot melt adhesive 31 can be determined as appropriate, and a dense pattern with scattered minute uncoated areas (spiral, Z-shaped, wavy spray application, etc.) is preferred, but a continuous surface application pattern such as slot application may also be used.

[0071] (Glycerin-containing area) The skin contact area 30E of the top sheet 30 contains glycerin at a concentration of 0.7-2.7 g / m², as shown in Figures 7, 10, and 11. 2It has a glycerin-containing region 32. The glycerin-containing region 32 may be provided in one place with a reasonably large area, or it may be provided in multiple places. The glycerin-containing region 32 may be provided in other areas or not, as long as it is provided in the skin contact area 30E of the top sheet 30.

[0072] The dimensions and arrangement of the glycerin-containing regions 32 can be determined as appropriate. However, it is undesirable for the dimensions of the glycerin-containing regions 32 to be too small. Preferably, one glycerin-containing region 32 has a dimension 32L in the MD direction (front-to-back direction LD in the illustrated example) of 5 mm or more, and a dimension 32W in the CD direction (width direction WD in the illustrated example) of 5 mm or more. The dimension 32L in the MD direction of the glycerin-containing region 32 is more preferably 30 mm or more, even more preferably 50 mm or more, and particularly preferably 100 mm or more. The upper limit of the dimension 32L in the MD direction of the glycerin-containing region 32 is the total product length Y, but it may be shorter. The dimension 32W in the CD direction of the glycerin-containing region 32 is more preferably 10 mm or more. The upper limit of the dimension 32W in the CD direction of the glycerin-containing region 32 is the width direction WD of the top sheet 30, but it may be shorter.

[0073] Furthermore, if the area of ​​the glycerin-containing area 32 within the skin contact area 30E is too small, the moisturizing effect on skin adhesion and friction reduction will be poor. Therefore, it is preferable that the area ratio of the glycerin-containing area 32 within the skin contact area 30E (total area of ​​the glycerin-containing area 32 / area of ​​the skin contact area 30E × 100) be 3% or more, and particularly 5% or more. Note that, as mentioned above, the skin contact area 30E refers to the area exposed on the surface of the article when it is unfolded. Therefore, if a part of the top sheet 30 is hidden by other components when it is unfolded (in the illustrated example, both sides of the top sheet 30 are hidden by the lifting gathers 60), it refers to the area excluding the hidden part. If the entire surface of the top sheet 30 is exposed on the surface of the product, it refers to the entire surface itself.

[0074] The glycerin-containing regions 32 are preferably arranged in a vertical stripe pattern as shown in the illustrated example, but they may also be arranged in a horizontal stripe pattern, a dot pattern, or a grid pattern. In these cases, the spacing 32X between adjacent glycerin-containing regions 32 can be determined as appropriate, but it is preferably about 1.5 to 10 mm.

[0075] The nonwoven fabric for Topsheet 30 has a fineness of 1-3 dtex (more preferably 1.5-2.5 dtex) and a basis weight of 10-30 g / m². 2 (more preferably 15-25 g / m 2 It is preferable to use a nonwoven fabric with a thickness of 0.4 to 1.4 mm (more preferably 0.5 to 1.0 mm). In other words, the fineness of the fibers in such a nonwoven fabric contributes to reducing surface friction, and combined with the friction-reducing effect of glycerin, the overall friction-reducing effect is improved. In addition, the fineness of the fibers improves the retention of glycerin, which also improves the friction-reducing effect. Furthermore, the glycerin contained in the top sheet 30 is transferred to the wearer's skin, which can moisturize (prevent dryness) the wearer's skin (especially by penetrating the stratum corneum). In short, the effect of reducing physical irritation to the wearer's skin and the effect of moisturizing the wearer's skin are highly compatible, and it is particularly excellent in preventing rashes. In particular, it is preferable that the average friction coefficient MIU of the glycerin-containing region 32 in the top sheet 30 is 0.2 to 0.4 due to the combination of the above nonwoven fabric and glycerin. Also, from these viewpoints, it is particularly preferable that the nonwoven fabric of the top sheet 30 is a short-fiber nonwoven fabric.

[0076] The surface moisture content of the glycerin-containing region 32 is not particularly limited, but a value of 3-10%, and especially 4-8%, is preferable because it can adequately moisturize the wearer's skin and prevent dryness.

[0077] To form the glycerin-containing region 32, a hydrophilic lotion containing glycerin can be applied to the top sheet 30 in a desired pattern. Particularly preferred hydrophilic lotions contain 70-90% by weight of glycerin and 10-30% by weight of water. Such a hydrophilic lotion, mainly composed of glycerin and containing an appropriate amount of water, is not only preferable as a moisturizer when applied to the skin, but also because the water is retained as bound water in the glycerin (glycerin has extremely high water-retaining properties), making it resistant to spoilage. 。

[0078] Hydrophilic lotions may contain one or more additives selected from the group consisting of emulsifiers, phosphate esters, paraffins, and surfactants. Preferred surfactants include ether-type nonionic surfactants and EO / PO-type nonionic surfactants. While hydrophilic lotions may contain preservatives to improve their shelf life, it is preferable that they do not contain preservatives, as they are transferred to the skin to moisturize it.

[0079] The glycerin content in glycerin-containing region 32 is 0.7 to 2.7 g / m². 2 It can be determined appropriately within the range of 1.0 to 2.2 g / m 2 It is more preferable that this is the case. For example, when a glycerin-containing region 32 is formed by applying a hydrophilic lotion containing 70-90% by weight of glycerin and 10-30% by weight of water to the top sheet 30, the amount of hydrophilic lotion applied to the glycerin-containing region 32 is 5-15 g / m². 2 The range can be set to a certain extent. As shown in the example in Figure 11, if there are multiple regions 32a, 32b with different hydrophilic lotion contents, or if the amount of hydrophilic lotion applied changes continuously, the glycerin-containing region 32 as a whole may be less or more than the above range, as long as it contains a portion within the above range.

[0080] The glycerin content will be measured using the following glycerin content measurement method. (Method for measuring glycerin content) Four identical products are prepared, and the dimensions of the glycerin-containing region 32 of any one of them are measured using the method described later, and the area of ​​the glycerin-containing region 32 (or the total area if there are multiple glycerin-containing regions 32) is determined. - Cut out all the glycerin-containing areas 32 from four top sheets 30 of the same product (it is not necessary to cut precisely along the edges; as long as the entire glycerin-containing area 32 is included, it is acceptable to include some of the surrounding area) and use all of these as test specimens, or remove four top sheets 30 of the same product and use them as test specimens. • Place the test specimen in a 300 ml beaker containing water at 25 degrees Celsius. Irregularly poke and stir the water with a glass rod for at least one minute, then leave it immersed in the water for 60 minutes. During this period, fold the test specimen and place a weight on it, or fix it in a folded state beforehand by gluing or sewing, so that the height of the test specimen in the beaker is as low as possible. The amount of water should be the minimum amount that allows the entire test specimen to be immersed (e.g., 10 ml). After this period, irregularly poke and stir the water with a glass rod for at least one minute, then lift the test specimen and squeeze it thoroughly. Measure the glycerin concentration of the glycerin-containing water remaining in the beaker using a glycerin concentration meter. Also, measure the weight of the glycerin-containing water remaining in the beaker. Based on these measurement results, determine the weight of glycerin contained in the glycerin-containing water. By dividing the glycerin weight of the glycerin-containing water by four times the area of ​​the glycerin-containing region 32 (for four product sheets), the glycerin content of the glycerin-containing region 32 (g / m²) can be calculated. 2 Calculate ).

[0081] While a nonwoven fabric made of hydrophobic resin fibers is preferable for the top sheet 30 due to its low cost, it would have poor glycerin retention when used with a hydrophilic lotion containing water. Therefore, the hydrophilic lotion is preferably 150-400 mPa·s in viscosity at 20°C. This is preferable to improve the glycerin retention in the nonwoven fabric.

[0082] For similar reasons, it is preferable to use a hydrophilic fiber nonwoven fabric, in which a hydrophilic agent is applied to hydrophobic resin fibers, for the top sheet 30. This is preferable because it enhances the glycerin retention in the nonwoven fabric.

[0083] As a hydrophilizing agent, considering safety to the human body and safety in the process, nonionic surfactants to which ethylene oxide has been added, such as higher alcohols, higher fatty acids, and alkylphenols, and anionic surfactants such as alkyl phosphate salts (octyl, dodecyl type) and alkyl sulfates are preferably used individually or in mixtures. The amount added varies depending on the required performance, but is usually about 0.1 to 2.0% by weight, and particularly about 0.2 to 1.0% by weight, relative to the dry weight of the target sheet.

[0084] <Sensory effect confirmation test> For the various top sheet samples shown in Tables 1-3, the average coefficient of friction MIU and surface moisture content were measured. rate etc. Various properties were measured. The glycerin content was measured using the measurement method described above. Samples 1-10 were nonwoven fabrics before assembly into a product, with or without hydrophilic lotion applied, while samples 11-15 were top sheets removed from commercially available products. In addition, the surface of each top sheet was stroked back and forth by hand to evaluate its smoothness and moistness in three stages (◎...very good, △...better than sample 5, ×...same) compared to sample 5.

[0085] [Table 1]

[0086] [Table 2]

[0087] [Table 3]

[0088] As shown in Tables 1-3, samples 1-4 and 6-9, and especially samples 1-4, 8, and 9, were found to have a very smooth and moist feel on the top sheet surface. In comparison, samples 10-15 were inferior in smoothness and moistness. Sample 9 was moist, but had a sticky texture.

[0089] <Measurement of transepidermal water loss (TEWL) and stratum corneum moisture content> The transepidermal water loss (TEWL) and stratum corneum water content were measured after the top sheet was in contact with the skin of subjects (two men and one woman in their thirties) for one hour using the following procedure. A portable water evaporation meter SWL-5001 from Delfin Technologies was used to measure TEWL. A skin surface stratum corneum water content measuring device SKICON-200EX-USB from Yayoi Co., Ltd. was used to measure the water content of each layer. (1) The top sheets of Sample 1 in Table 1, Sample 11 in Table 3, Sample 14 in Table 3, and Sample 15 in Table 3 were prepared and cut into 2 cm squares to make test specimens. For the Sample 1 test specimen, the specimen was cut so that the glycerin-containing area passed through the center. (2) Measurement points were marked on both of the subjects' arms at positions 8 cm, 11 cm, 14 cm, and 17 cm from the wrist (a total of 8 measurement points per person, 24 points in total for all subjects). (3) Approximately 0.1 g of fluff pulp was placed at each measurement point, 1 ml of alkaline aqueous solution (0.1 M NaCO3 aq.) was dropped onto the fluff pulp, and food wrap was wrapped around it to secure it. The area was left in this state for 1 hour. (4) After standing for 1 hour, the food wrap film and fluff pulp were removed, and the measurement points were lightly wiped with a test paper cloth. (5) After drying the measurement point for 15 minutes, the test specimen was placed on the measurement point and secured with cellophane adhesive tape, and left in that state for 1 hour. (6) After leaving for 1 hour, the sample was removed, and TEWL was measured three times at each measurement point. The average value of all the measured values for all the subjects was taken as the measurement result of TEWL. After measuring TEWL, the stratum corneum moisture content was measured three times at each measurement point, and the average value of all the measured values for all the subjects was taken as the measurement result of the stratum corneum moisture content.

[0090] The comparison graph of the measurement results of TEWL is shown in Fig. 13. Also, the comparison graph of the measurement results of the stratum corneum moisture content is shown in Fig. 14. From these measurement results, it was found that when using the top sheet (glycerin-containing) of Sample 1 having a glycerin-containing region, the moisture of the skin is less likely to escape to the outside and the moisture content of the skin is in a higher state than when using other top sheets that do not contain glycerin.

[0091] <Skin observation test by doctor> Samples of diapers having substantially the same structure as the tape-type disposable diapers shown in Figs. 1 to 5 and Fig. 10 and provided with the top sheet (glycerin-containing) of Sample 1 in Table 1 were prepared and used continuously by the subjects for one week. Before and immediately after use, a doctor observed the skin condition. The subjects were 33 healthy infants from 6 months to 1 year old who were using tape-type disposable diapers (those provided with a top sheet that does not contain glycerin).

[0092] As a result of observing the doctor's findings, no skin symptoms that became a problem were found after the test, and it was confirmed that 6 out of 7 subjects in whom erythema was confirmed in the observation before the test showed an improvement tendency.

[0093] <Measurement of IL-1α secretion amount> Using a three-dimensional culture skin model (immature model), the influence of the top sheet on IL-1α production was evaluated as follows.

[0094] As the three-dimensional culture skin model, SkinEthic RHE-D7 (EPISKIN, hereinafter referred to as RHE) was used and acclimation culture was performed for 2 hours in a 24-well plate using Growth medium (EPISKIN).

[0095] A top sheet similar to Sample 1 in Table 1 was prepared, and a blank test specimen was made by cutting it to match the surface shape of the RHE (circular shape with a diameter of 8 mm). Then, a hydrophilic lotion with the same composition and application amount as Sample 1 in Table 1 was applied to the entire surface of the blank to prepare a glycerin-containing test specimen. The test specimen was placed directly on the surface of the cultured RHE, allowed to settle, and incubated for 72 hours. 24 hours after placing the test specimen on the RHE, it was removed, replaced with fresh Growth medium and test specimen, and culture was continued. The culture medium was collected, and the amount of IL-1α secreted on Day 1 was measured by ELISA. After another 24 hours (total 48 hours), the test specimen was removed, replaced with fresh Growth medium and test specimen, and culture was continued. The culture medium was collected. The amount of IL-1α secreted on Day 2 was measured using the same procedure as on Day 1. After another 24 hours (total 72 hours), the test specimen was removed, the culture medium was collected, and the amount of IL-1α secreted on Day 3 was measured using the same procedure as on Day 1. The RHE was also collected and used for filaggrin level measurement as described below.

[0096] Similarly, in the case where nothing was placed on the surface of the RHE (control), IL-1α secretion levels were measured and the RHE was collected.

[0097] IL-1α secretion levels were measured by quantifying IL-1α in culture medium using a sandwich ELISA method, with HumanIL-1α / IL-1 F1 Antibody (MAB200) (R&D systems, Inc.), diluted to an appropriate concentration, as the capture antibody and HumanIL-1α / IL-1 F1 Biotinylated Antibody (BAF200) (R&D systems, Inc.), a biotin-labeled anti-IL-1α antibody, as the detection antibody. The details are as follows: After incubating a plate coated with the capture antibody with recovery medium diluted to a predetermined concentration, the detection antibody was added. Steptavidin-HRP (DY998) (R&D systems, Inc.) was added and the reaction was carried out, then substrate solution (DY999) (R&D systems, Inc.) was added and the reaction was carried out, and after stopping the reaction with Stop solution (DY994) (R&D systems, Inc.), the absorbance at 450 nm was measured.

[0098] When the amount of IL-1α in the models that fell below the detection limit was considered to be 0, the sum of the IL-1α amounts from Day 1 to Day 3 was as shown in Figure 15. When using blank test specimens, the result was 10.5 ± 4.9 (pg / model), while when using glycerin-containing test specimens, it was less than half that amount, at 4.7 ± 7.5 (pg / model).

[0099] <Measurement of filaggrin levels> Using a three-dimensional cultured skin model (immature model), the effect of the top sheet on filaggrin levels was evaluated as follows.

[0100] Frozen blocks of RHE (Rich Hemoglobin) collected during IL-1α secretion measurement, embedded in OCT compound, were used to prepare 5 μm thick sections. The sections were mounted on glass slides and air-dried. They were fixed at room temperature for 15 minutes using PBS(-) containing 4% paraformaldehyde, blocked at room temperature for 1 hour using PBS(-) containing 1% bovine serum albumin (BSA), and then reacted with anti-filaggrin antibody (GeneTex) overnight at 40°C. Anti-mouse IgG AlexaFluor 488 (Cell Signaling Technologies) was reacted as a secondary antibody at room temperature for 2 hours. Cell nuclei were stained with Hoechst 33342 (Cell Signaling Technologies) as a counterstain, mounted with Marinol (Muto Chemical Co., Ltd.), and the green (filaggrin) and blue (cell nucleus) fluorescence in the tissue was observed using a fluorescence microscope.

[0101] Observations revealed that, as shown in Figure 16, filaggrin expression was observed throughout the entire stratum corneum in the control group. Furthermore, when a blank specimen was placed on the stratum corneum surface, filaggrin expression decreased compared to the control group. In contrast, when a glycerin-containing specimen was placed on the stratum corneum surface, the decrease in filaggrin expression was suppressed compared to when a blank specimen was placed.

[0102] <Explanation of terms used in the specification> The following terms in this specification shall have the meanings set forth below, unless otherwise specified in this specification.

[0103] "Front-back direction" refers to the direction indicated by the symbol LD in the diagram (vertical direction), and "width direction" refers to the direction indicated by WD in the diagram (left-right direction). The front-back direction and the width direction are orthogonal to each other.

[0104] • "MD direction" and "CD direction" refer to the flow direction (MD direction) and the transverse direction (CD direction) perpendicular to it in the manufacturing equipment. Depending on the part of the product, one of these directions may be the front-to-back direction and the other the width direction. The MD direction of nonwoven fabric is the direction of fiber orientation of the nonwoven fabric. Fiber orientation is the direction along which the fibers of the nonwoven fabric run. For example, it can be determined by a measurement method compliant with the fiber orientation test method by zero-distance tensile strength of the TAPPI standard method T481, or by a simple measurement method that determines the fiber orientation direction from the ratio of tensile strength in the front-to-back and width directions.

[0105] "Front side" refers to the side that is closer to the wearer's skin when worn, while "back side" refers to the side that is further away from the wearer's skin when worn.

[0106] "Front side" refers to the side that is closer to the wearer's skin when worn, while "back side" refers to the side that is further away from the wearer's skin when worn.

[0107] • "Area ratio" refers to the proportion of the target portion to a unit area, and is expressed as a percentage by dividing the total area of ​​the target portion (e.g., holes) in the target area (e.g., cover nonwoven fabric) by the area of ​​the target area. In configurations where many target portions are provided at intervals, it is desirable to set the target area to a size that includes 10 or more target portions and then determine the area ratio. For example, the area ratio of holes can be measured using, for example, KEYENCE's product name VHX-1000, with the measurement conditions multiplied by 20, following the procedure below. (1) Set it on a 20x lens and adjust the focus. Adjust the position of the nonwoven fabric so that 4x6 holes fit inside. (2) Specify the brightness of the area of ​​the hole and measure the area of ​​the hole. (3) Click on the color extraction for "Area Measurement" under "Measurement / Comments". Click on the hole. (4) Click "Batch Measurement," check "Show Measurement Results Window," and save the data as a CSV file.

[0108] • "Elongation rate" refers to the value relative to the natural length, which is set at 100%. For example, an elongation rate of 200% is equivalent to an elongation ratio of 2.

[0109] The "gel strength" is measured as follows: 49.0 g of artificial urine (a mixture of urea: 2 wt%, sodium chloride: 0.8 wt%, calcium chloride dihydrate: 0.03 wt%, magnesium sulfate heptahydrate: 0.08 wt%, and deionized water: 97.09 wt%) is mixed with 1.0 g of superabsorbent polymer and stirred with a stirrer. The resulting gel is left in a constant temperature and humidity chamber at 40°C × 60% RH for 3 hours, then returned to room temperature, and the gel strength is measured using a card meter (I.techno Engineering: Curdmeter-MAX ME-500).

[0110] "Weight" is measured as follows: After pre-drying the sample or test piece, leave it in a test room or apparatus under standard conditions (temperature 23±1°C, relative humidity 50±2%) to reach a constant weight. Pre-drying means bringing the sample or test piece to a constant weight in an environment of 100°C. Note that pre-drying is not necessary for fibers with an official moisture content of 0.0%. Using a sample-taking template (100mm x 100mm), cut out a sample measuring 100mm x 100mm from the test piece that has reached a constant weight. Measure the weight of the sample, multiply it by 100 to calculate the weight per square meter, and this is the weight.

[0111] • "Thickness" was measured using an automatic thickness measuring instrument (KES-G5 handy compression measurement program) with a load of 0.098 N / cm². 2 , and pressure area: 2cm 2 The measurement is performed automatically under these conditions. The thickness of the perforated nonwoven fabric is measured in areas other than the holes and the protruding parts around them.

[0112] • Water absorption is measured according to JIS K7223-1996 "Test method for water absorption of superabsorbent polymers".

[0113] The water absorption rate shall be the "time to the endpoint" when 2 g of superabsorbent polymer and 50 g of physiological saline solution are used in the JIS K7224-1996 "Test method for water absorption rate of superabsorbent polymers".

[0114] "Unfolded state" refers to a state in which something is unfolded flat without contraction or sagging.

[0115] Unless otherwise specified, the dimensions of each part refer to the dimensions in the unfolded state, not the natural length state.

[0116] • "Melting viscosity" is measured at a specified temperature using a Brookfield Type B viscometer (spindle No. 027) in accordance with JIS Z 8803.

[0117] The "maximum dimension" of the hole refers to the longer of the two dimensions: the dimension in the MD direction and the dimension in the CD direction.

[0118] • If the "glycerin-containing region" can be identified visually, such as by coloring, its shape can be identified visually and its dimensions can be measured. On the other hand, if the glycerin-containing region 32 cannot be identified visually, it can be identified by an appropriate method. For example, by preparing the required number of test specimens (for measurement and for location identification) in which the glycerin-containing region 32 is in the same position, the glycerin-containing region 32 on the top sheet 30 of the location identification test specimen is colored with an appropriate coloring agent to a different color from the surrounding area, the colored position is identified using a ruler or an appropriate image measuring device, and then the same position as the colored position identified on the location identification test specimen is used as the glycerin-containing region 32 for measurement. As a material that can color the glycerin-containing region 32, Taseto Co., Ltd.'s water-leakage color-developing agent "Moremir W" can be suitably used. Furthermore, if the moisture content of the glycerin-containing region 32 is above a certain level, the glycerin-containing region 32 can be visualized (identified) as a darker area than the surrounding area by imaging the top sheet surface under illumination (indoor light and outdoor light from a window) using a near-infrared camera (NIRCam-640SN manufactured by Vision Sensing Co., Ltd.), and its dimensions can be measured.

[0119] • The "Average Friction Coefficient MIU" and "Average Friction Coefficient Variation Deviation MMD" refer to the values ​​measured using a friction tester KES-SE (10mm square silicone sensor, 50g load) manufactured by Kato Tech Co., Ltd., with a sensor movement distance of 20mm. The direction of sensor movement (friction direction) is the MD direction of the top sheet. When measuring a product, components other than the top sheet are removed or cut off to the extent that they do not affect the friction test of the top sheet surface (therefore, for example, components welded to the top sheet are not removed), and the test is performed in the unfolded state. Furthermore, if the CD-direction dimension of the glycerin-containing region in the top sheet is less than the sensor dimension (10 mm), as shown in Figure 12(a), the top sheet 30 is cut along the side edge of the glycerin-containing region 32 to create a test specimen 300 (narrower than the sensor 100) consisting only of the glycerin-containing region 32. Measurements are then taken on this test specimen, with the center of the sensor 100 aligned with the CD-direction center of the test specimen 300, as shown in Figure 12(b). Note that after each measurement, any glycerin or other substances adhering to the surface of the sensor 100 should be thoroughly wiped off before the next measurement. The glycerin-containing region 32 is identified using the method described above.

[0120] The "surface moisture content" is calculated as the average value obtained by measuring any three locations within the glycerin-containing region 32 using a Scalar moisture checker (MY-808S). After each measurement, any glycerin or other substances adhering to the measurement surface of the moisture checker should be thoroughly wiped off before the next measurement. The glycerin-containing region 32 is identified using the method described above.

[0121]

[0122] Viscosity is measured at a specified temperature using a Brookfield Type B viscometer (spindle No. 027) in accordance with JIS Z 8803.

[0123] Unless otherwise specified, the tests and measurements shall be conducted in a test room or apparatus under standard conditions (temperature 23±1°C, relative humidity 50±2%). [Industrial applicability]

[0124] This invention can be used for a wide range of disposable wearable items, including pant-type disposable diapers, tape-type disposable diapers, pad-type disposable diapers, disposable swimwear, diaper covers, sanitary napkins, and more. [Explanation of Symbols]

[0125] 11...Liquid-impermeable sheet, 12...Outer nonwoven fabric, 14...Pore, 14e...Protrusion, 30...Top sheet, 30E...Skin contact area, 31...Hydrophobic hot melt adhesive, 32...Glycerin-containing area, 40...Intermediate sheet, 50...Absorbent element, 56...Absorbent body, 58...Packaging sheet, 60...Rising gather, 62...Gathered sheet, 90...Group, 93...Non-porous area, 94...Unit arrangement area, LD...Front-to-back direction, WD...Width direction.

Claims

1. An absorbent material is built into the area including the groin, The absorbent material has a top sheet positioned on its outer surface, which includes a skin contact area that comes into contact with the wearer's skin, The aforementioned top sheet has a fineness of 1 to 2.5 dtex and a basis weight of 10 to 30 g / m. ２ It is a short-fiber nonwoven fabric with a thickness of 0.5 to 1.4 mm. The aforementioned short-fiber nonwoven fabric is a hydrophilic fiber nonwoven fabric in which a hydrophilic agent is coated onto hydrophobic resin fibers. The skin contact area has a glycerin-containing area that contains a hydrophilic lotion comprising 70-90% by weight of glycerin and 10-30% by weight of water. The viscosity of the hydrophilic lotion at a temperature of 20°C is 150 to 400 mPa·s. The glycerin-containing region has a glycerin content of 0.7 to 2.7 g / m². ２ The portion includes a portion having a dimension of 5 mm or more in the MD direction and a dimension of 5 mm or more in the CD direction. The glycerin content in the skin contact area is 0.7 to 2.7 g / m². ２ The area ratio of that portion is 3% or more. The glycerin content in the glycerin-containing region is 0.7 to 2.7 g / m². ２ The average friction coefficient MIU of that part is 0.2 to 0.

4. In the glycerin-containing region, the surface moisture content of the portion where the glycerin content is 0.7 to 2.7 g / m² is 4 to 10%. Disposable wearable articles characterized by the following features.

2. The top sheet is a perforated nonwoven fabric having a pore arrangement region in which holes penetrating from the front to the back are arranged in a predetermined pattern. The skin contact area comprises the glycerin-containing area, the pore arrangement area, and the overlapping area where the glycerin-containing area and the pore arrangement area overlap. The top sheet is bonded to a backing member located on the back side of the top sheet via a hydrophobic hot-melt adhesive, at least over the entire pore arrangement region. The disposable wearable article according to claim 1.

3. The glycerin-containing region is continuous in the front-to-back direction throughout the entire length of the product, with multiple portions having different glycerin content connected in the front-to-back direction. The total glycerin content of the glycerin-containing region is 0.7 g / m². ２ less A disposable wearable article according to claim 1 or 2.

4. The amount of IL-1α secreted, measured by contacting the glycerin-containing region of the top sheet with a three-dimensional cultured skin model, is less than or equal to half the amount of IL-1α secreted when the top sheet differs only in that it does not contain glycerin. The amount of filaggrin measured by contacting the glycerin-containing region of the top sheet with a three-dimensional cultured skin model is greater than the amount of filaggrin measured in the case of a top sheet that differs only in that it does not contain glycerin. A disposable wearable article according to any one of claims 1 to 3.

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