Disposable diaper
Patent Information
- Application Number
- JP2023031045
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2023-03-01
- Publication Date
- 2025-12-22
Smart Images
Figure 00000000_0000_ABST
Abstract
Description
[Technical field]
[0001] The present invention relates to a disposable diaper. [Background technology]
[0002] A disposable diaper includes, for example, a top sheet, a back sheet, and an absorbent disposed between the top sheet and the back sheet. Typically, the disposable diaper is provided with three-dimensional gathers that stand up toward the wearer's skin to prevent leakage of excrement from the leg openings. However, if there is a large amount of excrement or if the wearer moves a lot, the disposable diaper may slip down, causing gaps, which may allow the excrement to leak over the three-dimensional gathers.
[0003] In contrast, the disposable diaper described in Patent Document 1 has, in addition to the first leakproof cuffs which are three-dimensional gathers, second leakproof cuffs which are formed by the backsheet extending outward in the width direction of the absorbent body and joining to the exterior body. [Prior art documents] [Patent documents]
[0004] [Patent Document 1] JP 2016-120018 A Summary of the Invention [Problem to be solved by the invention]
[0005] However, in the disposable diaper described in Patent Document 1, the outer body and the extended back sheet are joined together, which may cause the joint to become hard, resulting in a concern that the wearing comfort may be deteriorated.
[0006] The present invention relates to a disposable diaper which prevents leakage of body waste from standing gathers and provides a comfortable fit. [Means for solving the problem]
[0007] A disposable diaper according to one embodiment of the present invention has a vertical direction extending from the wearer's abdominal side through the crotch region to the dorsal side, and a horizontal direction perpendicular to the vertical direction and corresponding to the wearer's left-right direction, and is divided into a abdominal region arranged on the abdominal side, a crotch region arranged in the crotch region, and a dorsal region arranged in the dorsal region. The disposable diaper includes an absorbent body, a top sheet, a standing gather, a back sheet, and an exterior body. The top sheet is placed on the skin side of the absorbent body. The three-dimensional gathers are arranged on both sides in the vertical direction and stand up toward the skin side. The back sheet is disposed on the non-skin side of the absorbent body and has an extension portion extending outward in the lateral direction from the standing gathers. The exterior body is placed on the non-skin side of the backsheet and forms a leg opening, and has leg gathers formed by arranging a first elastic member along the circumferential direction of the leg opening. The back sheet has moisture permeability, the extension portion is not joined to the exterior body, and the extension portion is not joined to the first elastic member. Effect of the Invention
[0008] According to the disposable diaper of the present invention, leakage of excrement from the standing gathers is suppressed and a high wearing comfort is obtained. [Brief description of the drawings]
[0009] [Figure 1] FIG. 1 is a schematic perspective view showing an example of a disposable diaper according to a first embodiment of the present invention. [Diagram 2] 1 is an exploded perspective view of a disposable diaper according to a first embodiment. FIG. [Diagram 3] FIG. 2 is a plan view of a disposable diaper according to the first embodiment, showing the disposable diaper unfolded and spread out flat with the elastic members of each part stretched, as viewed from the skin side (surface material side). [Figure 4]FIG. 4 is a schematic cross-sectional view of the disposable diaper according to the first embodiment taken along line IV-IV in FIG. [Diagram 5] FIG. 1 is a plan view showing an example of an absorbent core constituting a part of a disposable diaper according to a first embodiment. [Figure 6] FIG. 1 is a schematic cross-sectional view showing an example of a disposable diaper according to a first embodiment when worn. [Figure 7] 1 is a graph showing an example of a pore size distribution of a back sheet constituting a part of a disposable diaper according to a first embodiment, in which the horizontal axis represents pore size (μm) and the vertical axis represents pore volume (ml / g). [Figure 8] FIG. 2 is a plan view showing a schematic structure of a moisture-permeable film constituting the back sheet. [Figure 9] FIG. 4 is a schematic cross-sectional view of a disposable diaper according to a second embodiment when worn. [Figure 10] FIG. 1 is a plan view of a disposable diaper according to a third embodiment, showing the disposable diaper unfolded and spread out flat with the elastic members of each part stretched, as viewed from the skin side (surface material side). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0010] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the following embodiment, an example in which a disposable diaper according to the present invention is configured as a pants-type disposable diaper will be given. In the following description of each embodiment, the same reference numerals are used for the configurations already described, and the description thereof may be omitted. In addition, in Fig. 6 and Fig. 9, the adhesive is omitted in order to make the drawings easier to see.
[0011] First Embodiment [Overall composition of disposable diapers] 1 to 4 show a pants-type disposable diaper 1 as an absorbent article according to a first embodiment of the present invention. The pants-type disposable diaper 1 will be referred to as diaper 1 hereinafter. The diaper 1 has a longitudinal direction X, a transverse direction Y, and a thickness direction Z. The longitudinal direction X extends from the wearer's abdomen through the crotch area to the back. The transverse direction Y is perpendicular to the longitudinal direction X and corresponds to the left-right direction of the wearer. The thickness direction Z is perpendicular to the longitudinal direction X and the transverse direction Y of the diaper 1. In this specification, with respect to the lateral direction Y, the side closer to the vertical center line CL that divides the diaper 1 in half in the lateral direction Y is referred to as the "inner side in the lateral direction Y," and the side away from the vertical center line CL is referred to as the "outer side in the lateral direction Y." In this specification, when each component is viewed from the thickness direction Z, it is referred to as a plan view. In this specification, the skin side of each component refers to the side that is located on the skin side of the wearer when the disposable diaper is worn. In each component, the non-skin side refers to the side that is located opposite to the skin side of the wearer when the disposable diaper is worn. In addition, with regard to the thickness direction Z, the side that is closer to the wearer's skin when worn may be referred to as the top, and the side that is closer to the clothing may be referred to as the bottom.
[0012] As shown in Figs. 1 to 3, the diaper 1 has a waist opening 1W and a pair of leg openings IL, and is placed around the waist and crotch area of a wearer when worn. The diaper 1 is divided into a ventral region A, which is arranged on the ventral side of the wearer when worn, a dorsal region B, which is arranged on the dorsal side of the wearer when worn, and a crotch region C, which is located between the ventral region A and the dorsal region B and is arranged in the crotch area of the wearer when worn. The ventral region A, the crotch region C, and the dorsal region B are arranged along the longitudinal direction X. The ventral region A and the dorsal region B are joined at their side edges A1, B1 in the lateral direction Y to form a waist opening 1W. Leg openings are formed in the crotch region C, which form leg openings 1L. 3 shows the diaper 1 unfolded and laid out flat to the designed dimensions with the elastic members of each portion stretched and all effects of the elastic members completely eliminated. Unfolding the diaper 1 means unfolding the side edge portion A1 of the abdominal region A and the side edge portion B1 of the dorsal region B separately.
[0013] As shown in Fig. 4, the diaper 1 comprises a top sheet 2, an absorbent body 4, a side sheet 5, a back sheet 3, and an exterior body 6. The diaper 1 has a configuration in which the exterior body 6, the back sheet 3, the absorbent body 4, and the top sheet 2 are laminated in the thickness direction Z. These components are joined together by a known joining means such as a hot melt adhesive.
[0014] As shown in Figs. 1 to 3, the absorbent body 4 is disposed across the abdominal region A, crotch region C, and back region B. The absorbent body 4 is disposed between the top sheet 2 and the back sheet 3. The absorbent body 4 absorbs liquid excrement such as urine of the wearer (hereinafter referred to as "excrement") from the surface on the top sheet 2 side, and diffuses the excrement inside to retain the excrement. The absorbent body 4 has an absorbent core 40 and a core wrap sheet 41 . The absorbent core 40 is mainly composed of an absorbent material capable of retaining excreted liquid. Specifically, the absorbent core 40 has a structure in which a hydrophilic fiber stack is supported with a water-absorbent polymer, or a structure made of only a water-absorbent polymer, or the like. The core wrap sheet 41 covers the absorbent core 40 and has a function of, for example, maintaining the shape of the absorbent core 40. The core wrap sheet 41 is formed of, for example, a thin, soft paper such as tissue paper or a liquid-permeable nonwoven fabric. The absorbent body 4 will be described in detail later.
[0015] The top sheet 2 is disposed so as to contact the wearer's skin when the diaper 1 is worn. The top sheet 2 is disposed at least on the skin side (upper side in the thickness direction Z) of the absorbent body 4. In the example shown in Fig. 4, the top sheet 2 is disposed so as to extend from the skin side of the absorbent body 4 to the side edge portions 4s in the lateral direction Y, and further wrap around to the non-skin side of the absorbent body 4. The top sheet 2 is configured as a liquid-permeable sheet material and is formed of a nonwoven fabric containing synthetic or natural fibers. Materials commonly used in the technical field of absorbent articles can be used as the material for the top sheet 2. Various nonwoven fabrics can be used as the sheet material, such as nonwoven fabrics produced by the carding method, spunbond nonwoven fabrics, meltblown nonwoven fabrics, spunlace nonwoven fabrics and needlepunched nonwoven fabrics, and meltblown nonwoven fabrics, spunlace nonwoven fabrics and needlepunched nonwoven fabrics.
[0016] The exterior body 6 is disposed on the non-skin side (lower in the thickness direction Z) of the absorbent body 4, more specifically on the non-skin side of the backsheet 3, and forms, for example, the outer surface of the non-skin side of the diaper 1. From the viewpoint of realizing a good feel against the skin, the exterior body 6 is preferably made of a nonwoven fabric, and further, from the viewpoint of imparting leakproofness, it is preferable that the exterior body 6 has functions such as low liquid permeability, water vapor permeability, and water repellency. In the example shown in FIG. 4, the exterior body 6 includes a skin side sheet 61 and a non-skin side sheet 62. As shown in Figs. 1 to 3, the exterior body 6 forms a waist opening 1W and leg openings 1L. The exterior body 6 further includes a waist elastic member 63 arranged along the waist opening 1W, and a leg elastic member 64 as a first elastic member arranged along the leg opening 1L. The exterior body 6 has leg gathers G1 formed by arranging the leg elastic members 64. The exterior body 6 is preferably composed of a plurality of sheet materials, and the waist elastic member 63 and the leg elastic member 64 are arranged, for example, between a skin side sheet 61 and a non-skin side sheet 62. The exterior body 6 is folded back at the waist opening 1W, and the vicinity of the waist opening edge may be composed of three or more layers of sheets.
[0017] A pair of side sheets 5 are disposed on the skin side of the lateral direction Y side of the top sheet 2, forming a three-dimensional gather G3. Specifically, the non-skin side end of the side sheet 5 is joined to a non-skin side member (the back sheet 3 in the example of FIG. 4) by adhesive, heat sealing, or the like. On the other hand, the skin side end of the side sheet 5 is configured as a free end that is not joined to other members, and a thread-like or band-like tip-proximal elastic member 51 is disposed. The tip-proximal elastic member 51 is disposed near the tip 53 of the three-dimensional gather G3. In the example shown in the figure, one tip-proximal elastic member 51 is disposed, but multiple pieces may be disposed. The tip-proximal elastic member 51 extends in the vertical direction X and is attached to the side sheet 5 in a stretched state. As a result, when worn, the skin side end of the side sheet 5 stands up against the skin side due to contraction of the tip-proximal elastic member 51, forming a three-dimensional gather 50. The side sheet 5 is made of a sheet material having functions such as poor liquid permeability and water repellency, and is made of a nonwoven fabric as an example.
[0018] The back sheet 3 is disposed on the non-skin side of the absorbent body 4. In this embodiment, the back sheet 3 is made of a resin film. The back sheet 3 may have functions such as poor liquid permeability and water repellency. As described later, the back sheet 3 may also have moisture permeability. The back sheet 3 is disposed between the absorbent body 4 and the exterior body 6. The back sheet 3 is bonded to the non-skin side of the absorbent body 4 by an adhesive H1, and is bonded to the exterior body 6 by an adhesive H2. The back sheet 3 will be described in detail later.
[0019] [Absorber composition] As shown in FIG. 5, the absorbent body 4 has a pair of deformation guides 42 extending in the longitudinal direction X in the crotch region C and disposed on either side of the center in the lateral direction Y. The deformation guide portion 42 is a portion that becomes the starting point of folding of the absorbent body 4. The deformation guide portion 42 may be configured to guide the folding of the absorbent body 4, and may be configured, for example, as any of a slit, a low basis weight portion, a compressed portion, or a portion with a crease in the absorbent core 40. The slit means a through hole having an elongated shape in a plan view and penetrating the absorbent core 40 in the thickness direction Z. The low basis weight portion refers to a portion of the absorbent core 40 having a lower basis weight than the surrounding area. The compressed portion refers to a portion where the absorbent core 40 is compressed and reduced in thickness by compression processing. The creased portion is a portion in which a crease has been formed by a process such as folding and pressing the absorbent body 4 or the absorbent core 40 . Of these, from the viewpoint of reliably inducing bending, the deformation guide 42 is preferably configured with a slit or a low basis weight portion, and more preferably configured with a slit as shown in Figs.
[0020] The deformation guide portion 42 may be disposed at least in the crotch region C, and may extend to at least one of the abdominal region A and the dorsal region B. In addition, the deformation guide portion 42 is not limited to a configuration extending over the entire length of the crotch region C, and may extend in the longitudinal direction X in at least a part of the crotch region C. The phrase "the deformation inducing portion 42 extends in the longitudinal direction X" is not limited to a mode in which the deformation inducing portion 42 extends parallel to the longitudinal direction X, but may be any mode in which the deformation inducing portion 42 extends from the ventral side to the dorsal side as a whole. The shape of the deformation inducing part 42 in plan view is not particularly limited as long as it is elongated in the vertical direction X. In the example shown in Fig. 5, the deformation inducing part 42 is configured in a linear (strip) shape, and the dimension in the width direction perpendicular to the extension direction of the deformation inducing part 42 is substantially constant. Alternatively, the dimension in the width direction of the deformation inducing part 42 may change along the extension direction.
[0021] The center in the lateral direction Y of the absorbent body 4 means a region on a vertical center line CL that divides the diaper 1 into two equal parts in the lateral direction Y. That is, the pair of deformation guide parts 42 are disposed on both sides of the vertical center line CL in the lateral direction Y. The pair of deformation guide parts 42 divide the diaper 1 into a central region 43 and a side region 44.
[0022] That is, the absorbent body 4 has a central region 43 located between a pair of deformation guides 42 and side regions 44 located on the outer sides in the lateral direction Y of the central region 43 . The central region 43 is a region sandwiched between a pair of deformation inducing portions 42. That is, as shown in Fig. 5, a side edge portion 43s of the central region 43 in the horizontal direction Y is a boundary portion with the deformation inducing portion 42, and coincides with an inner edge portion on the inner side in the horizontal direction Y of the deformation inducing portion 42. An end portion of the central region 43 in the vertical direction X is a portion connecting the ends of the pair of deformation inducing portions 42 in the vertical direction X. The side regions 44 are regions located outward in the lateral direction Y from side edge portions 43s of the central region 43 (that is, inner edge portions of the deformation guide portions 42).
[0023] Here, since the width of the wearer's crotch is generally narrower than the width of the absorbent body 4 in the lateral direction Y, when the diaper is worn, the absorbent body 4 bends from the deformation guide portion 42 as a starting point. That is, as shown in Fig. 6, the absorbent body 4 deforms to fit into the wearer's crotch K, and the central region 43 and the side regions 44 rise up toward the skin side. As a result, the absorbent body 4 deforms into a concave shape with the central region 43 as the bottom and the side regions 44 as the upright portions. Based on the concave deformation of the absorbent body 4, the top sheet 2 also deforms, forming a recess R on the skin side of the diaper 1, which makes it easier for excrement such as urine and feces to temporarily accumulate and makes it easier for more excrement to be supplied to the central region 43.
[0024] 2 and 4, the base end 54 of the three-dimensional gathers G3 is the root of the three-dimensional gathers G3 and is located on the non-skin side of the absorbent body 4. Therefore, when worn, the three-dimensional gathers G3 rise from the base end 54 on the non-skin side of the absorbent body 4 to the skin side through the vicinity of both left and right side edges of the absorbent body 4, which makes it easier for the side regions 44 of the absorbent body 4 to rise up, allowing the absorbent body 4 to maintain a concave shape more stably, making it easier for excrement to accumulate in the recesses R, and making it easier for more excrement to be supplied to the central region 43.
[0025] 4 and 6, in the diaper 1, the absorbent body 4 has an absorbent body elastic member 45 as a second elastic member disposed in the side region 44 and extending in the longitudinal direction X. The diaper may not have the absorbent body elastic member 45. The absorber elastic member 45 is a strip-shaped or thread-shaped elastic member. The phrase "the absorber elastic member 45 extends in the longitudinal direction X" does not mean that the absorber elastic member 45 is parallel to the longitudinal direction X, but includes a mode in which the absorber elastic member 45 extends from the ventral side to the dorsal side as a whole. The absorber elastic members 45 are attached to the left and right side edges by adhesive or the like in a state stretched from their natural length. The absorber elastic members 45 extend at least in the crotch region C, and may extend to the ventral side and / or the dorsal side of the side regions 44 in the longitudinal direction X.
[0026] In the above configuration, the elastic members 45 for the absorber apply a contractile force along the longitudinal direction X to the side regions 44 of the absorber 4, forming absorber gathers G2 on both side edges of the absorber 4. This makes it easier for the side regions 44 to stand up from the deformation guides 42 when worn. Therefore, when worn, the absorber 4 can more stably maintain a concave shape, making it easier for excrement to accumulate in the recesses R, and making it easier for more excrement to be supplied to the central region 43.
[0027] The absorbent body elastic member 45 is preferably disposed at the side edge portion 4s in the lateral direction Y of the absorbent body 4. This allows the entire side region 44 to stand up stably. In this case, from the viewpoint of preventing the absorbent body elastic member 45 from falling off, the absorbent body elastic member 45 is preferably disposed on the outer surface of the side edge portion 4s (for example, on the core wrap sheet 41) and covered by the top sheet 2. As another embodiment in which the absorbent body elastic member 45 is disposed at the side edge portion 4s, it may be disposed between the side edge portion in the lateral direction Y of the absorbent core 40 and the core wrap sheet 41.
[0028] [Back sheet configuration] The back sheet 3 has moisture permeability from the viewpoint of releasing water vapor derived from excreted fluids, sweat, etc. to the outside and suppressing stuffiness. "Moisture permeability" means the property of water vapor diffusing from a high humidity side to a low humidity side according to the second law of thermodynamics without air movement. Moisture permeability can be evaluated by the value of moisture permeability measured based on, for example, JIS Z0208.
[0029] The moisture permeability can be measured in accordance with JIS Z0208. First, a cup containing calcium chloride as a moisture absorbent is prepared, and the cup is placed so that it is horizontal. The mass of calcium chloride before the test is measured in advance. A test piece is prepared by cutting the back sheet into a circle with a diameter 10 mm larger than the inner diameter of the cup, and the test piece is placed on the upper edge of the cup and adjusted so that the periphery of the test piece is located on a concentric circle of the upper edge of the cup. A ring-shaped packing is prepared along the upper edge of the cup, and the packing is pressed so that the periphery of the test piece is in close contact with the upper edge of the cup. Furthermore, a ring-shaped weight is placed on top of it, and a test specimen is prepared in which a moisture-permeable film is fixed to the upper edge of the cup. This test specimen is left for 1 hour at a temperature of 30°C ± 0.5°C and a humidity of 90 ± 2% RH, and the mass of calcium chloride after the test is measured. The value obtained by subtracting the mass of calcium chloride before the test from the mass of calcium chloride after the test is calculated, and this is used as the water vapor transmission surface of the test specimen for 100 cm. 2 The moisture permeability is calculated by converting it into a permeability value.
[0030] In order to achieve moisture permeability, the back sheet 3 is preferably composed of a moisture permeable film having a plurality of fine pores (microvoids). The moisture permeable film includes, for example, a resin film, and may have a single-layer structure or a laminated structure. The moisture permeable film can be obtained, for example, by melt-kneading a hydrophobic thermoplastic resin (such as a polyolefin resin) and inorganic fine particles (such as calcium carbonate) that are incompatible with the thermoplastic resin to form a film, and then stretching the film uniaxially or biaxially. The film can be formed, for example, by an inflation method, a T-die method, or the like.
[0031] 2 to 4 and 6, the backsheet 3 has an extension portion 31 that extends outward in the horizontal direction Y from the base end portion 54 of the three-dimensional gathers G3. The extension portion 31 extends in the vertical direction X. No adhesive is provided between the extension portion 31 and the exterior body 6, and the extension portion 31 and the exterior body 6 are not joined together. In addition, no adhesive is provided between the extension portion 31 and the three-dimensional gathers G3, and the extension portion 31 and the three-dimensional gathers G3 are not joined together. In addition, in FIG. 3 and FIG. 10 showing a diaper according to a third embodiment described later, the extensions 31 are indicated by dots.
[0032] The extension portion 31 is not joined to the leg elastic member 64 that is disposed in the leg opening 1L of the side sheet 5 and forms the leg gather G1. Here, the extension portion 31 being not joined to the leg elastic member 64 includes a form in which the extension portion 31 is not joined to the leg elastic member 64 in a state of direct contact therewith, as well as a form in which the extension portion 31 is not joined to the leg elastic member 64 in a state of indirect contact therewith via another sheet member. In this embodiment, as shown in Figs. 4 and 6, the leg elastic member 64 is disposed between the skin side sheet 61 and the non-skin side sheet 62, and the extension portion 31 is not joined to the leg elastic member 64 in a state of indirect contact therewith via the skin side sheet 61, and the leg elastic member 64 is not joined to the extension portion 31.
[0033] [Effects]
[0034] In the diaper 1 of the present invention, the back sheet 3 has moisture permeability, and the extension portion 31, which is a part of the back sheet 3, is not joined to other members such as an exterior body. This configuration provides a high wearing comfort, prevents the diaper 1 from slipping down when worn, and prevents leakage from the three-dimensional gathers. This will be described in detail below.
[0035] When the diaper 1 is worn, the moisture (excreted liquid) from the excrement absorbed by the absorbent body 4 evaporates as water vapor within the diaper. By disposing the moisture-permeable back sheet 3 on the non-skin side of the absorbent body 4, heat dissipation occurs when water vapor is released through the micropores of the moisture-permeable film that constitutes the back sheet 3.
[0036] Here, when the diaper 1 is worn, the wearer's excretory part is generally located opposite the lateral Y central region of the skin side of the absorbent 4 in the crotch region C, so that excrement is easily supplied to the lateral Y central region, and while the lateral Y side regions are easily wetted and tend to be relatively dry. Urine and other excrement is warm for about 30 minutes immediately after excretion, and a temperature difference occurs between the lateral Y central region (wet region) wetted by the excrement and the lateral Y side regions (dry regions) which are dry. For this reason, the above-mentioned heat dissipation phenomenon is particularly likely to increase near the boundary between the wet region and the dry region, and the water vapor that has evaporated inside the diaper is liquefied and easily adheres to the skin. This allows the contact points between the extension portion 31 and the skin to be in a moderately wet state, and the extension portion 31 can be brought into close contact with the skin with improved friction between the extension portion 31 and the skin.
[0037] Furthermore, because the extension portions 31 are not joined to other members such as the exterior body 6 and the leg elastic members 64, the leg gathers G1 are soft, and when worn, the extension portions 31 are easily brought into contact with the wearer's skin, so that the extension portions 31 are soft and adhere to the skin. This provides a soft, comfortable fit, and the extension portions 31 adhere to the skin to follow the movements of the body, and the contact is more easily maintained when the friction between the extension portions 31 and the skin is increased due to the wet state.
[0038] In this way, when worn, the friction between the extension portion 31 and the skin is increased due to the wet state, and the extension portion 31 comes into contact with the skin, and this friction makes it difficult for the diaper 1 to slip down due to the weight of the body waste, bodily movements, etc., and prevents the diaper 1 from slipping down, creating gaps that allow the body waste to leak over the three-dimensional gathers G3. Even if the body waste does leak over the three-dimensional gathers G3, the extension portion 31 located outside the three-dimensional gathers G3 in the lateral direction Y prevents the body waste from leaking out of the diaper 1.
[0039] As described above, the diaper 1 prevents leakage of body waste from the standing gathers and is highly comfortable to wear.
[0040] Furthermore, in the diaper 1 of this embodiment, in order to enhance the effect of the extension portions 31 in preventing the diaper 1 from slipping down, the absorbent body 4 is provided with a pair of deformation guide portions 42 formed by slits. As described above, by providing the deformation guide 42, when worn, the absorbent 4 deforms into a concave shape with the central region 43 as the bottom and the side regions 44 as the upright portions, making it easier for more excreted liquid to be supplied to the central region 43. Furthermore, due to the presence of the deformation guide 42 by the slits, excreted liquid absorbed in the central region 43 is less likely to transfer to the side regions 33. This makes it possible to more reliably form the boundary between the wet region and the dry region within the absorbent body 4, and the above-mentioned heat dissipation phenomenon is more likely to occur. This makes it easier to moisten the skin, and makes it easier to bring the extension portions 31 into closer contact with the skin under conditions of increased friction between the extension portions 31 and the skin, thereby preventing the diaper 1 from slipping down when worn and preventing leakage of excrement from the three-dimensional gathers. Furthermore, when worn, the deformation guide portion 42 causes the absorbent body 4 to deform into a concave shape with the central region 43 as the bottom and the side regions 44 as the upright portions, making it easier to maintain the concave shape of the recess R even when the absorbent body 4 expands in the lateral direction Y due to the absorption of excretory liquid, preventing the extension portion 31 from separating from the skin and making it easier to maintain contact between the extension portion 31 and the skin.
[0041] The same effect can be obtained even when the deformation guide portion 42 is formed of a low basis weight portion. The same effect can also be obtained when the deformation guide section 42 is configured as a compressed section. The compressed section has a higher constituent fiber density than other non-compressed areas, so excreted liquid absorbed in the central area 43 is less likely to diffuse beyond the compressed section into the side areas 44. This ensures that the boundary between the wet area and the dry area can be reliably formed, and the same effect can be obtained in the compressed section as in the case of a slit.
[0042] The absorbent body does not have to have a deformation guide portion. Even in a diaper in which the absorbent body does not have a deformation guide portion, since generally, more excrement is likely to be supplied to the transverse Y central region in the crotch region, a boundary may be formed between the transverse Y central region (wet region) that is wet by the liquid excretion portion and the transverse Y side regions (dry regions) that are dry. However, from the viewpoint of increasing the above-mentioned heat radiation phenomenon at the boundary between the wet region and the dry region in the absorbent body, it is more preferable to provide a deformation guide portion, which can further prevent the diaper from slipping down.
[0043] In the diaper 1 of this embodiment, in order to enhance the effect of the extension parts 31 in preventing the diaper 1 from slipping down, the absorbent body 4 is provided with elastic members 45 for the absorbent body that are disposed in the side regions 44 and extend in the longitudinal direction. With this configuration, the elastic member 45 for the absorber applies a contraction force along the longitudinal direction X to the side regions 44 of the absorber 4B. As a result, when worn, the side regions 44 are more likely to stand up from the deformation guides 42, and the absorber 4 can stably maintain a concave shape when worn, making it easier for excrement to accumulate in the concave portions R. In other words, excrement is more likely to be supplied to the central region 43, making the central region 43 more likely to become wet than the side regions 44. As a result, a boundary between the wet region and the dry region is more likely to be formed, making it easier to cause the above-mentioned heat dissipation phenomenon, and the extension portions 31 can be brought into close contact with the skin in a state where the skin is moistened and the friction between the extension portions 31 and the skin is improved, thereby preventing the diaper from slipping down.
[0044] [supplementary explanation] 4, in order to allow the extension portion 31 to adhere more closely to the skin and prevent the diaper from slipping down, the dimension a of the extension portion 31 in the lateral direction Y (hereinafter sometimes referred to as "width") is preferably 2 mm or more, and more preferably 7 mm or more. Although the extension portion 31 is shown in Fig. 4 as having a curved shape, the width a of the extension portion 31 is the dimension when the extension portion 31 is stretched out straight. The width a of the extension 31 is preferably shorter than the height of the standing gather G3. This configuration can prevent the extension 31 from being rolled into the standing gather G3, and as shown in FIG. 6, when worn, the extension 31 can be reliably positioned outside the standing gather G3 in the lateral direction Y and can be closely attached to the skin. Furthermore, when putting the diaper 1 on a wearer, the extension 31 can be prevented from getting caught on the wearer's legs, and the diaper can be put on smoothly. The height of the standing gather G3 corresponds to the length from the base end 54 to the tip end 53 (see FIG. 2). The height of the standing gather G3 is typically about 15 mm to 50 mm.
[0045] From the viewpoints of providing a diaper 1 that is highly moisture permeable and comfortable with little stuffiness, while also ensuring leakproofness and maintaining an appropriate moist state at the contact points between the extensions 31 and the skin to improve frictional force and prevent the diaper 1 from slipping down, the moisture permeability value of the backsheet 3 measured in accordance with the above-mentioned JIS Z0208 is preferably 1.5 g / 100 cm 2 h or more, preferably 1.7 g / 100 cm 2 h or more, preferably 3.6 g / 100 cm 2 h or less, preferably 3.4 g / 100 cm 2 ·h or less. In order to achieve such moisture permeability, the back sheet 3 is preferably a moisture permeable film 30 containing a plurality of fine pores.
[0046] In the back sheet 3, it is preferable that the pore volume per unit mass of the micropores having an opening diameter in the range of 0.06 μm to 0.16 μm is larger than the pore volume per unit mass of the micropores having an opening diameter in the range of 2.5 μm to 3.5 μm. This allows a large number of micropores having an opening diameter in the range of 0.06 μm to 0.16 μm to be formed, thereby increasing the permeability of water vapor (moisture). On the other hand, the number of micropores having an opening diameter in the range of 2.5 μm to 3.5 μm can be regulated, thereby more reliably preventing moisture leakage. Therefore, a back sheet 3 that is both moisture permeable and leakproof can be obtained.
[0047] (Method of measuring pore volume) The pore volume can be measured by the following method in accordance with the mercury intrusion method specified in JIS R 1655. First, a measurement sample of a predetermined size (for example, 10 mm x 10 mm) is cut out from the moisture-permeable film 30 to be measured. This measurement sample is set in a mercury porosimeter (for example, "Autopore IV9520" manufactured by Shimadzu Corporation), and the pore size distribution in the pore diameter range of 0.06 μm to 3.5 μm is measured. Based on the obtained pore size distribution (see FIG. 7), the cumulative pore volume in the pore diameter range of 0.06 μm to 0.16 μm and the cumulative pore volume in the pore diameter range of 2.5 μm to 3.5 μm are measured. If the cumulative pore volume in the pore diameter range of 0.06 μm or more and 0.16 μm or less is greater than the cumulative pore volume in the pore diameter range of 2.5 μm or more and 3.5 μm or less, it is determined that "the pore volume per unit mass of micropores having pore diameters in the range of 0.06 μm or more and 0.16 μm or less is greater than the pore volume per unit mass of micropores having pore diameters in the range of 2.5 μm or more and 3.5 μm or less."
[0048] As such, a method for forming a large number of small micropores 37 includes, for example, a method of uniformly stretching the moisture-permeable film 30. As shown in FIG. 8(A), when the moisture-permeable film 30 is stretched non-uniformly, a region that is not sufficiently stretched is generated in a part of the moisture-permeable film 30, and a portion where the small inorganic fine particles 36 cannot be sufficiently opened (unopened portion 38 shown by a thick line) may be formed. Furthermore, in the region where the stretching force is large within the surface of the moisture-permeable film 30, the inorganic fine particles 36 are dragged to a large extent, so that large micropores 37 are formed, and in the region where the stretching force is small, the inorganic fine particles 36 are not dragged so much, so that small micropores 37 are easily formed. For this reason, the size of the micropores 37 may not be correlated with the size of the inorganic fine particles 36.
[0049] In contrast, as shown in Fig. 8(B), when the moisture-permeable film 30 is stretched uniformly, a sufficient stretching force is applied to the small inorganic fine particles 36 as well. As a result, the portion that was an unopened portion 38 in the example of Fig. 8(A) becomes a sufficiently opened micropore 37 (portion shown by a thick line) in Fig. 8(B), and the number of small micropores 37 can be increased. Furthermore, when the moisture-permeable film 30 is stretched uniformly within its plane, micropores 37 corresponding to the size of the inorganic fine particles 36 are easily formed, and therefore there is a tendency for the size of the micropores 37 and the size of the inorganic fine particles 36 to be positively correlated.
[0050] As an index of whether the moisture-permeable film 30 is uniformly stretched, the moisture-permeable film 30 has a thickness of 0.01 μm or less in a plan view seen from the thickness direction Z. 2 More than 0.5μm 2 The pore diameter of the micropores adjacent to the inorganic fine particles having a size of 1.0 μm or less 2 More than 1.5μm 2 It is preferable that the diameter of the micropores is smaller than the diameter of the micropores adjacent to the inorganic fine particles having the following size: In the above configuration, since the moisture-permeable film 30 is uniformly stretched, the number of small micropores 37 adjacent to the small inorganic fine particles 36 can be increased, and the moisture-permeable film 30 having high moisture permeability and leak prevention can be obtained.
[0051] (Method of measuring size of inorganic fine particles and pore diameter of fine pores) An evaluation sample of a predetermined size (for example, 10 mm x 10 mm) is cut out from the moisture-permeable film 30. The cut-out evaluation sample is fixed in place in a standard manner and imaged at 1000 times magnification using a scanning electron microscope (SEM). From one image, image analysis techniques are used to extract the outlines of the portions corresponding to the inorganic microparticles and the adjacent micropores. The size of the area corresponding to the extracted inorganic microparticles and the size of the area corresponding to the adjacent micropores are measured. The pore diameter of the micropores is obtained by calculating the circle equivalent diameter from the size (area) of the area corresponding to the extracted micropores. Images of 100 locations are captured from one sheet of moisture-permeable film 30, and the images are analyzed to obtain an average diameter of 0.01 μm. 2 More than 0.5μm 2The average pore size of the micropores adjacent to inorganic fine particles having a size of 1.0 μm or less and 2 More than 1.5μm 2 The average pore diameter of the micropores disposed adjacent to the inorganic fine particles having the following sizes is calculated.
[0052] As described above, when the micropores 37 are formed according to the size of the inorganic fine particles 36, the pore diameter of the micropores 37 can be controlled by controlling the size distribution of the inorganic fine particles 36. From this viewpoint, in the moisture-permeable film 30, the pore diameter of the micropores 37 can be controlled within a range of 0.01 μm in plan view as seen from the thickness direction Z. 2 More than 0.5μm 2 The number of particles per unit area of inorganic fine particles 36 with a size of 0.5 μm or less is 2 2.0μm or more 2 The number of particles per unit area of inorganic fine particles 36 having a size of less than 2.0 μm 2 The number of particles per unit area of the above inorganic fine particles 36 is 0.5 μm 2 2.0μm or more 2 It is preferable that the number of particles per unit area is smaller than the number of inorganic fine particles 36 having a size of less than 1 mm. With the above-mentioned configuration, a large number of minute pores 37 can be formed, and a moisture-permeable film 30 that satisfies both moisture permeability and leak prevention properties can be obtained.
[0053] The basis weight of the back sheet 3 is preferably 20 g / m2 so as to easily follow the movement of the wearer. 2 Less than 18g / m 2 From the viewpoint of water resistance, it is preferably 11 g / m 2 More preferably, 13 g / m 2 From the viewpoint of achieving both the ability to follow the wearer's movements and water resistance, it is preferable that the thickness be 11 g / m 2 More than 20g / m2 and less than 13g / m2 2 More than 18g / m 2 The following is the result.
[0054] <Second embodiment> A diaper 1A according to a second embodiment will be described with reference to Fig. 9. The following description will focus on configurations that differ from the first embodiment.
[0055] As in the diaper 1A of the second embodiment, the diaper 1A may include a proximal elastic member 52 as a third elastic member disposed near the proximal end 54 of the standing gathers G3A and extending in the vertical direction. The proximal elastic member 52 is disposed near the proximal end 54, specifically at a site approximately 3 mm to 12 mm away from the proximal end 54. Although the diaper 1A of the second embodiment is configured without an elastic member for the absorber, it may be provided with an elastic member 45 for the absorber as in the diaper 1 of the first embodiment.
[0056] As with the diaper 1 of the first embodiment, the diaper 1A also has an extension portion 31 that is not joined to other components, and the back sheet 3 including the extension portion 31 has moisture permeability, which allows for a high wearing comfort, prevents the diaper 1 from slipping down when worn, and prevents leakage of excrement from the three-dimensional gathers.
[0057] Furthermore, in the diaper 1A, by providing the proximal elastic member 52 near the proximal end 54 of the standing gathers G3A to form the gathers, the concave shape of the recess R is easily maintained and the extensions 31 are more likely to fit closely to the shape of the wearer's crotch. This makes it possible to further prevent the diaper 1 from slipping down when worn and to prevent leakage of excrement from the standing gathers G3A.
[0058] <Third embodiment> A diaper 1B according to a third embodiment will be described with reference to Fig. 10. The following will focus on the configuration different from the first embodiment.
[0059] The arrangement of leg elastic members 64 forming leg gathers G1 of a diaper 1B according to the third embodiment will be described below. As shown in Fig. 10, the outer cover 6 has leg gathers G1 formed by arranging leg elastic members 64B as first elastic members in the circumferential direction of the leg opening 1L. The leg elastic members 64B have a ventral leg elastic member 65 and a dorsal leg elastic member 66.
[0060] The abdominal leg elastic member 65 has an outer end 65a in the abdominal region A and an inner end 65b in the crotch region C. The abdominal leg elastic member 65 is arranged along the circumferential direction of the leg opening 1L from the outer end 65a to the inner end 65b, and then curves gradually to become approximately parallel to the horizontal direction Y near the center in the vertical direction X of the crotch region C and extends in the horizontal direction Y toward the inside in the horizontal direction Y.
[0061] The back leg elastic member 66 has an outer end 66a in the back region B and an inner end 66b in the crotch region C. The back leg elastic member 66 is arranged along the circumferential direction of the leg opening 1L from the outer end 66a to the inner end 66b, and then curves gradually to become approximately parallel to the horizontal direction Y near the center in the vertical direction X of the crotch region C and extends in the horizontal direction Y toward the inside in the horizontal direction Y.
[0062] 10, the abdominal leg elastic member 65 and the dorsal leg elastic member 66 gradually curve to become substantially parallel to the horizontal direction Y near the center in the vertical direction X of the crotch region C, extend inward in the horizontal direction Y, intersect with the extension portion 31 extending in the vertical direction X in a plan view, and further extend inward in the horizontal direction Y beyond the extension portion 31. The leg elastic member 64B has a portion 67 extending in the horizontal direction Y in the crotch region C. The portion 67 refers to a portion of the leg elastic member 64B that gradually curves to become substantially parallel to the horizontal direction Y and extends inward in the horizontal direction Y. The leg elastic member 64 has an overlapping portion 640 where an inner end 65b of the abdominal leg elastic member 65 and an inner end 66b of the dorsal leg elastic member 66 overlap. The overlapping portion 640 is located in a region where the absorber 4 and the back sheet 3 overlap when viewed in plan from the skin side (the side where the top sheet is located) of the diaper 1 in an unfolded state with each elastic member stretched. In this embodiment, the overlapping portion 640 is formed by overlapping a part of a portion of the abdominal leg elastic member 65 extending in the lateral direction Y in the crotch region C with a part of a portion of the abdominal leg elastic member 65 extending in the lateral direction Y in the crotch region C. In addition, in Figure 10, the inner ends 65b and 66b are illustrated to explain the positional relationship between the inner ends 65b and 66b and the back sheet 3. However, in reality, when the diaper 1 is viewed from the top sheet 2 side, the inner ends 65b and 66b are hidden by the absorbent body 4, etc.
[0063] In this manner, the leg elastic members 64B have a portion 67 extending in the lateral direction Y in the crotch region C, and the portion 67 and the backsheet 3 overlap in the crotch region C.
[0064] As with the diaper 1 of the first embodiment, the diaper 1B also has an extension portion 31 that is not joined to other components, and the back sheet 3 including the extension portion 31 has moisture permeability, which allows for a high wearing comfort, prevents the diaper 1 from slipping down when worn, and prevents leakage of excrement from the three-dimensional gathers.
[0065] Furthermore, in the diaper 1B, the leg elastic members 64B have an area 67 extending in the horizontal direction Y in a part of the crotch region C, and the area 67 overlaps with the backsheet 3, thereby suppressing elongation in the vertical direction X near the area 67 in the exterior body 6. This makes it possible to suppress sagging of the crotch region C due to the weight of excrement, makes it easier to maintain adhesion between the extensions 31 and the skin, and further prevents the diaper 1 from slipping down when worn.
[0066] <Other embodiments> Although the embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment, and it goes without saying that various modifications can be made without departing from the spirit of the present invention.
[0067] For example, in the above embodiment, the disposable diaper is configured as a pants-type disposable diaper, but the present invention is not limited to this. For example, the disposable diaper may be a tape-type disposable diaper, a pants-type sanitary product, or the like. [Explanation of symbols]
[0068] 1, 1A, 1B... Disposable diapers 1L…Leg opening 2. Top sheet 3. Back seat 31...Extending part 4…Absorbent 6…Exterior body 64... Leg elastic member (first elastic member) A...ventral region B...Dorsal region C...Inseam area G1…Leg gathers G3…3D gathers
Claims
1. A disposable diaper having a vertical direction extending from a wearer's abdomen side through a crotch region to a dorsal side, and a horizontal direction perpendicular to the vertical direction and corresponding to the left-right direction of the wearer, and being divided into a abdomen region disposed on the abdomen side, a crotch region disposed in the crotch region, and a dorsal region disposed in the dorsal region, An absorber; a top sheet disposed on the skin side of the absorbent body; Three-dimensional gathers are arranged on both sides in the vertical direction and stand up toward the skin side; a backsheet disposed on the non-skin side of the absorbent body and having an extension portion extending outward in the lateral direction from the three-dimensional gathers; an exterior body disposed on the non-skin side of the backsheet and forming leg openings, the exterior body having leg gathers formed by arranging first elastic members along the circumferential direction of the leg openings; Equipped with The back sheet is moisture permeable, the extension portion is not joined to the exterior body, and the extension portion is not joined to the first elastic member. Disposable diapers.
2. The horizontal dimension of the extension is 2 mm or more. The disposable diaper according to claim 1.
3. The absorber has a pair of deformation guide portions that extend in the longitudinal direction in the crotch region and are arranged on either side of the center in the lateral direction, The absorbent body has a central region located between the pair of deformation guides and side regions located laterally outward of the central region. The disposable diaper according to claim 1 or 2.
4. The absorbent body further includes second elastic members disposed in the side regions and extending in the longitudinal direction. The disposable diaper according to claim 3.
5. The standing gathers have a third elastic member that is disposed near a base end of the standing gathers and extends in the vertical direction. The disposable diaper according to claim 1 or 2.
6. the first elastic member has a portion extending in the lateral direction in the crotch region, In the crotch region, the laterally extending portion and the backsheet overlap. The disposable diaper according to claim 1 or 2.
7. The moisture permeability of the back sheet is 1.5 g / 100 cm ２ ・It is greater than or equal to h The disposable diaper according to claim 1 or 2.
8. The back sheet has a basis weight of 20 g / m ２ is The disposable diaper according to claim 1 or 2.
9. The back sheet is made of a moisture-permeable film having a plurality of micropores, In the back sheet, The pore volume per unit mass of micropores having an opening diameter in the range of 0.06 μm or more and 0.16 μm or less is larger than the pore volume per unit mass of micropores having an opening diameter in the range of 2.5 μm or more and 3.5 μm or less. The disposable diaper according to claim 1 or 2.
10. The back sheet is made of a moisture-permeable film having a plurality of micropores, the backsheet has fine calcium carbonate particles disposed adjacent to the micropores; In the back sheet, in a plan view seen from the thickness direction, 0.01 μm ２ More than 0.5 μm ２ The opening diameter of the micropores arranged adjacent to the calcium carbonate particles having a size of 1.0 μm or less ２ More than 1.5 μm ２ The opening diameter of the micropores arranged adjacent to the calcium carbonate particles is smaller than the opening diameter of the micropores arranged adjacent to the calcium carbonate particles having a size of The disposable diaper according to claim 1 or 2.
11. The backsheet has a plurality of micropores, the backsheet has fine calcium carbonate particles disposed adjacent to the micropores; In the back sheet, in a plan view seen from the thickness direction, 0.01 μm ２ More than 0.5 μm ２ The number of particles per unit area of the calcium carbonate particles having a size of 0.5 μm or less is ２ 2.0 μm or more ２ The number of particles per unit area of the calcium carbonate particles having the following size is less than 2 μm ２ The number of particles per unit area of the calcium carbonate particles having a size of 0.5 μm or more is ２ 2.0 μm or more ２ The number of particles per unit area of the calcium carbonate particles having the following size is less than The disposable diaper according to claim 1 or 2.