Underpants type absorbent article
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2025-09-09
- Publication Date
- 2026-03-12
AI Technical Summary
Existing pants-type absorbent articles face difficulty in adequately pulling up the crotch area during donning, leading to potential leakage, especially in sleeping wearers like newborns, as the pulling force is not effectively transmitted to areas not overlapping with the belt.
Incorporating a plurality of crotch elastic members arranged in equal width regions of the absorbent core, extending in the longitudinal direction, to facilitate the transmission of pulling force to the crotch region, including the absorbent core, thereby ensuring the crotch area is pulled up as a whole during donning.
The configuration effectively prevents leakage by ensuring the crotch area is properly lifted during use, particularly in sleeping wearers, by enhancing the pulling-up performance through the use of crotch elastic members.
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Abstract
Description
[Technical Field]
[0001] One aspect of the present invention relates to a pant-type absorbent article. [Background technology]
[0002] Patent Document 1 describes a pants-type absorbent article comprising a ventral outer sheet that covers the ventral side of the wearer's waist and a back outer sheet that covers the back side, with a tubular waist portion formed by joining the joints of both widthwise edges of the ventral outer sheet and the joints of both widthwise edges of the back outer sheet, and an absorbent main body whose front end is connected to the inner surface of the widthwise center of the ventral outer sheet and whose rear end is connected to the inner surface of the widthwise center of the back outer sheet, and which covers from the back side through the crotch area to the abdominal side. [Prior art documents] [Patent documents]
[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2008-178682 Summary of the Invention [Problem to be solved by the invention]
[0004] When wearing the pants-type absorbent article described above, the tubular waistband (belt) is pulled up. However, even when the belt is pulled up, the pulling force is not easily transmitted to areas of the absorbent main body that do not overlap with the belt (below the belt), such as the crotch area, making it difficult to pull up. If the crotch area is not pulled up sufficiently, leakage may occur.
[0005] One aspect of the present invention has been made in consideration of the above-mentioned situation, and aims to provide a pants-type absorbent article that can properly pull up the crotch area when pulling up when putting on the article, thereby preventing leakage, etc. [Means for solving the problem]
[0006] A pants-type absorbent article according to one embodiment of the present invention comprises an absorbent body having a liquid-absorbent core, a belt portion having a ventral waist portion located at one end of the absorbent body in the longitudinal direction and a dorsal waist portion located at the other end of the absorbent body in the longitudinal direction, and a plurality of crotch elastic members arranged on the absorbent core and extending in the longitudinal direction, and at least one or more crotch elastic members are arranged in each of three equal width regions of the absorbent core that intersect the longitudinal direction.
[0007] In a pants-type absorbent article according to one aspect of the present invention, a plurality of crotch elastic members extending in the longitudinal direction are disposed on the absorbent core. With this configuration, when the belt portion is pulled up during the pulling-up action at the time of putting on the article, the pulling force is easily transmitted to the crotch region including the absorbent core via the crotch elastic members. In addition, in a pants-type absorbent article according to one aspect of the present invention, one or more crotch elastic members are disposed in each of three equal widthwise regions of the absorbent core (i.e., the central region and the left and right end regions), and the crotch elastic members are disposed over a wide area in the width direction, so that the crotch region including the absorbent core can be pulled up as a whole during the pulling-up action. As described above, with the pants-type absorbent article according to one aspect of the present invention, the crotch region can be pulled up as a whole during the pulling-up action at the time of putting on the article, effectively preventing leakage and the like. This effect is particularly pronounced when the wearer is sleeping, such as a newborn baby. In other words, for a sleeping wearer such as a newborn, it is difficult to pull up the crotch area to the desired position by pulling up, but by arranging crotch elastic members in each of three equal width regions of the absorbent core, the pulling up performance during the pulling up operation is improved, and even for a sleeping wearer such as a newborn, the crotch area can be pulled up as a whole, effectively preventing leakage, etc.
[0008] The plurality of crotch elastic members may be arranged so as to straddle a center line that is a folded line intersecting the longitudinal direction of the absorbent core and that becomes the lower end of the crotch section when worn. By arranging the crotch elastic members so as to straddle the center line that becomes the lower end of the crotch section in this way, the lower end of the crotch section can be pulled up via the crotch elastic members during the pulling-up action, and the crotch part can be pulled up more effectively.
[0009] The multiple crotch elastic members may be arranged biased toward the ventral waistband or the back waistband with respect to the center line. In some cases, the absorbent core is difficult to pull up on either the ventral waistband or the back waistband. In this regard, by arranging the crotch elastic members biased toward the more difficult-to-pull side of the ventral waistband or the back waistband, the more difficult-to-pull side can be pulled up preferentially via the crotch elastic members. Furthermore, by arranging the crotch elastic members biased toward the ventral waistband, the fit of the absorbent core near the crotch area can be improved. Furthermore, by arranging the crotch elastic members biased toward the back waistband, the back body can be pulled up more easily when lying down.
[0010] The plurality of crotch elastic members may be arranged biased toward the side of the ventral waistband and the back waistband with a relatively low contractile force. The side of the ventral waistband and the back waistband with a relatively low contractile force is less likely to be pulled up in conjunction with each other during the pulling-up operation when putting on the garment. In this regard, by arranging the crotch elastic members biased toward the side with a low contractile force, the side with a low contractile force can be more effectively pulled up during the pulling-up operation.
[0011] The multiple crotch elastic members may be arranged so as not to overlap either the ventral waistband or the back waistband, or so as to overlap one of the ventral waistband or the back waistband but not the other. If the crotch elastic members extend into a region overlapping with the belt, there is a risk that a force will be applied to the belt in a downward direction via the crotch elastic members after wearing. In this regard, by arranging the crotch elastic members so as not to overlap at least both the ventral waistband and the back waistband that constitute the belt, even if a force is applied to the crotch elastic members in a downward direction, the force is prevented from being strongly transmitted to the belt, thereby effectively preventing the belt from being pulled down.
[0012] The longitudinal central portion of the absorbent core may be formed into a constricted shape that is concave inward in the width direction, and the effective length of the crotch elastic member in the longitudinal direction may be shorter than the longitudinal length of the constricted portion when the absorber is unfolded. By making the effective length of the crotch elastic member shorter than the constricted shape of the longitudinal central portion in this way, the vicinity of the constricted shape of the longitudinal central portion can be easily contracted, effectively lifting the crotch portion and appropriately preventing the crotch elastic member from reaching both longitudinal end sides and pulling down the belt portion.
[0013] At a center line of the absorbent core that intersects the longitudinal direction and forms the lower end of the crotch section when worn, the distance from the outermost crotch elastic member in the width direction included in the plurality of crotch elastic members to the width direction end of the absorbent core may be shorter than the separation distance between two adjacent crotch elastic members included in the plurality of crotch elastic members. With this configuration, the crotch elastic member is located close to the width direction end of the absorbent core, so that the crotch section including the absorbent core can be pulled up as a whole surface during the pulling-up operation.
[0014] The absorbent main body has longitudinally stretchable leg-hole elastic members at both widthwise ends thereof, and the crotch elastic members may have a higher elastic modulus than the leg-hole elastic members. By using such crotch elastic members, the contractile force of the crotch region is increased, enabling the crotch region to be pulled up effectively.
[0015] A lifting design indicating the lifting point when worn may be formed in at least one of the area where the absorbent main body and the ventral waistline portion overlap and the area where the absorbent main body and the dorsal waistline portion overlap. With this configuration, the lifting design is formed in the area where the waistline portion and the absorbent main body overlap, i.e., in the area where the lifting force is easily transmitted to the absorbent main body (absorbent core) when pulling up the belt portion, so that the user can be encouraged to properly pull up the crotch part including the absorbent core.
[0016] The lifting design may be formed on a line in the longitudinal direction of the widest part of the absorbent core in the width direction. With this configuration, the lifting design is formed in an area where the crotch part including the absorbent core can be pulled up as a whole in the pulling action, thereby encouraging the user to properly pull up the crotch part including the absorbent core.
[0017] The lifting design may be formed on the longitudinal end of the absorbent core. With this configuration, the lifting design is formed in an area where the absorbent core itself can be directly pulled up, thereby encouraging the user to properly pull up the crotch region including the absorbent core.
[0018] The lifting design may be formed continuously along the longitudinal direction from the area where the absorbent main body and the ventral waistband overlap to the area where the absorbent main body and the dorsal waistband overlap. With this configuration, the lifting design is formed continuously, including in the crotch area, making it easier for the user to visualize the correct lifting direction.
[0019] The lifting design may be formed in multiple locations spaced apart in the width direction. With this configuration, the lifting design can be formed at the gripping position of both hands during the actual lifting motion, thereby encouraging the user to perform the appropriate lifting motion.
[0020] A pair of lifting designs may be arranged on the outer sides of the crotch elastic members so as to sandwich the crotch elastic members in the width direction. With this configuration, the lifting designs are formed in an area where force can be appropriately transmitted to all of the crotch elastic members, i.e., an area where the crotch portion including the absorbent core can be pulled up as a whole, thereby encouraging the user to appropriately pull up the crotch portion including the absorbent core.
[0021] The distance between the pair of lifting designs may be no more than twice the distance between the widthwise outermost crotch elastic members included in the plurality of crotch elastic members. With this configuration, the distance between the crotch elastic member and the lifting design can be reduced in the widthwise direction, so that when a lifting operation is performed according to the lifting design, a lifting force can be appropriately transmitted to the crotch elastic member, and the crotch region can be effectively pulled up via the crotch elastic member.
[0022] A plurality of crotch elastic members may be arranged in each of the two equal width regions of the absorbent core. By arranging a plurality of crotch elastic members in each of the two equal width regions, a sufficient pulling force can be ensured in each region, and the crotch region including the absorbent core can be pulled up as a whole.
[0023] A pants-type absorbent article according to one aspect of the present invention comprises an absorbent main body having a liquid-absorbent core, a belt portion having a ventral waistband portion located at one longitudinal end of the absorbent main body and a dorsal waistband portion located at the other longitudinal end of the absorbent main body, and a plurality of crotch elastic members arranged on the absorbent core and stretchable in the longitudinal direction, the pants-type absorbent article being of a first size and having the same absorbent main body dimensions when stretched as other pants-type absorbent articles of a second size, and the same stretched dimensions of the belt portion as other pants-type absorbent articles, and having at least one of the number, contractile force, and arrangement area of the crotch elastic members greater than those of the other pants-type absorbent articles. In the pants-type absorbent article according to one aspect of the present invention, the stretched dimensions of the absorbent main body and the stretched dimensions of the belt portion are the same as those of the other pants-type absorbent article of the second size, and at least one of the number, contractile force, and arrangement area of the crotch elastic members is greater than those of the other pants-type absorbent articles. According to this configuration, it is possible to provide a pant-type absorbent article of a first size that is smaller than the second size by increasing at least one of the number, contraction force, and arrangement area of the crotch elastic members while using the same paper pattern dimensions as other pant-type absorbent articles of a second size. In this way, by adjusting the size of the pant-type absorbent article using the crotch elastic members, it is possible to provide a pant-type absorbent article of a shape that fits the size of the wearer while improving the ability to pull up the crotch area using the crotch elastic members. [Effects of the Invention]
[0024] According to one aspect of the present invention, the crotch area can be appropriately pulled up during the pulling-up action when putting on the underwear, thereby preventing leakage and the like. [Brief explanation of the drawings]
[0025] [Figure 1] 1 is a perspective view of a pants-type absorbent article according to an embodiment. [Figure 2] 1 is a plan view of a pants-type absorbent article according to an embodiment, unfolded and stretched, as viewed from the non-skin-facing side. [Figure 3]1 is a plan view of a pants-type absorbent article according to an embodiment, unfolded and stretched, as viewed from the skin-facing side. [Figure 4] FIG. 10 is a plan view of a pants-type absorbent article according to a modified example, unfolded and stretched, as viewed from the non-skin-facing side. [Figure 5] FIG. 10 is a plan view of a pants-type absorbent article according to a modified example, unfolded and stretched, as viewed from the non-skin-facing side. DETAILED DESCRIPTION OF THE INVENTION
[0026] Hereinafter, pants-type absorbent articles according to embodiments of the present invention will be described in detail with reference to the drawings. In each drawing, the same or corresponding parts are designated by the same reference numerals, and duplicated explanations will be omitted. Note that the drawings are schematic, and the ratios of dimensions may differ from those of the actual product.
[0027] [Overall schematic configuration of pants-type absorbent article] FIG. 1 is a perspective view of a pants-type absorbent article 1 according to this embodiment. FIG. 2 is a plan view of the pants-type absorbent article 1 according to this embodiment, unfolded and stretched, as viewed from the non-skin-facing side. FIG. 3 is a plan view of the pants-type absorbent article 1 according to this embodiment, unfolded and stretched, as viewed from the skin-facing side. The "unfolded" state (unfolded state) is a state in which the side portions 30a of the ventral waistband 30 (see FIG. 1) and the side portions 40a of the back waistband 40 (see FIG. 1) are separated from each other, and the entire pants-type absorbent article 1 is unfolded in a plane. The "stretched" state (stretched state) is a state in which the pants-type absorbent article 1 is stretched to a state in which no wrinkles are formed. More specifically, the stretched state is a state in which the dimensions of each component (e.g., the ventral waistband 30, etc.) constituting the pants-type absorbent article 1 are stretched until the dimensions of the component alone match or are close to those of the component. In the following description, the "skin-facing side" refers to the side that faces the wearer's skin when the pant-type absorbent article 1 is in use (worn), and the "non-skin-facing side" refers to the side that faces away from the wearer's skin when the pant-type absorbent article 1 is in use (worn). Also, the "wearer" refers to a person who wears the pant-type absorbent article 1, and the "wearer" refers to a person who puts the pant-type absorbent article 1 on the wearer.
[0028] In the following, the up-down direction of the pant-type absorbent article 1 when worn (see Figure 1) may be referred to as the "up-down direction," the longitudinal direction of the pant-type absorbent article 1 when stretched (see Figures 2 and 3) may be referred to as the "longitudinal direction," and the width direction of the pant-type absorbent article 1 when stretched (see Figures 2 and 3) may be referred to as the "width direction." The "longitudinal direction" is the direction extending from the front to the rear of the wearer's body when the pant-type absorbent article 1 is worn. One side of the longitudinal direction may be referred to as the "ventral side," and the other side as the "dorsal side." The "width direction" is the direction that corresponds to the left-right direction of the wearer when the pant-type absorbent article 1 is worn.
[0029] The pants-type absorbent article 1 is, for example, a pants-type disposable diaper. The pants-type absorbent article 1 may be a pants-type disposable diaper for children or a pants-type disposable diaper for adults. In this embodiment, an example will be described in which the pants-type absorbent article 1 is a pants-type disposable diaper for children, particularly for newborns.
[0030] The pants-type absorbent article 1 has a so-called three-piece configuration and includes an absorbent main body 10, a ventral waist portion 30, and a rear waist portion 40. The pants-type absorbent article 1 also includes a plurality of crotch elastic members 50 that are disposed on the absorbent core 13a of the absorbent main body 10 and extend in the longitudinal direction. The crotch elastic members 50 will be described in detail below. The ventral waist portion 30 and the rear waist portion 40 are generally rectangular in plan view, and extend in the width direction. The ventral waist portion 30 covers the wearer's ventral side, and the rear waist portion 40 covers the wearer's rear side. The absorbent main body 10 is generally rectangular in plan view, and extends in the longitudinal direction of the pants-type absorbent article 1.
[0031] In the pants-type absorbent article 1, the ventral waist portion 30 is located at the ventral end portion 10a (see FIG. 3), which is one end side of the absorbent main body 10 in the longitudinal direction, and the back waist portion 40 is located at the back end portion 10b (see FIG. 3), which is the other end side of the absorbent main body 10 in the longitudinal direction. The non-skin-facing side of the ventral end portion 10a is joined to the ventral waist portion 30 with an adhesive or the like (not shown), and the non-skin-facing side of the back end portion 10b is joined to the back waist portion 40 with an adhesive or the like (not shown). In this state, as shown in FIG. 1, the absorbent main body 10 is folded in half so that the ventral waist portion 30 and the back waist portion 40 face each other, and the widthwise side portion 30a of the ventral waist portion 30 and the widthwise side portion 40a of the back waist portion 40 are welded and joined, thereby forming the pants-type absorbent article 1 into a pants shape. The ventral waist portion 30 and the rear waist portion 40 form a belt portion 5. As shown in Fig. 1, the pants-type absorbent article 1 is formed with a waist opening BH and a pair of leg openings LH.
[0032] As shown in FIGS. 2 and 3 , the ventral waistline portion 30 includes a skin-facing sheet 31, a non-skin-facing sheet 32, and a plurality of thread-like elastic members 33. The non-skin-facing sheet 32 is disposed on the non-skin-facing side of the skin-facing sheet 31. The skin-facing sheet 31 and the non-skin-facing sheet 32 are disposed on the non-skin-facing side of the absorbent body 10. Examples of non-stretchable sheets that can be used for the skin-facing sheet 31 and the non-skin-facing sheet 32 include SMS nonwoven fabrics (spunbond, meltblown, and spunbond nonwoven fabrics), spunbond nonwoven fabrics, air-through nonwoven fabrics, plastic sheets, perforated plastic sheets, and laminates thereof. The skin-facing sheet 31 and the non-skin-facing sheet 32 are bonded together with an adhesive such as a hot melt adhesive. The plurality of thread-like elastic members 33 are disposed vertically between the skin-facing sheet 31 and the non-skin-facing sheet 32 and are fixed in a stretched state in the width direction. This allows the ventral waistline portion 30 to stretch in the width direction and fit the waist of the wearer. The thread-like elastic members 33 are made of elastic materials such as rubber or spandex. As shown in FIG. 2, the thread-like elastic members 33 may be arranged in the ventral waistline portion 30 so that they are not provided in part of the region overlapping the absorbent core 13a (details of which will be described later) of the absorbent main body 10. That is, the thread-like elastic members 33 may be cut midway in the width direction. This makes it possible to prevent the stretching of the thread-like elastic members 33 in the width direction, which is required to fit the ventral waistline portion 30 to the waist, from affecting the positioning of the absorbent core 13a, etc.
[0033] As shown in FIGS. 2 and 3 , the back-side waistband portion 40 includes a skin-facing sheet 41, a non-skin-facing sheet 42, and a plurality of thread-like elastic members 43. The non-skin-facing sheet 42 is disposed on the non-skin-facing side of the skin-facing sheet 41. The skin-facing sheet 41 and the non-skin-facing sheet 42 are disposed on the non-skin-facing side of the absorbent body 10. Examples of non-stretchable sheets that can be used for the skin-facing sheet 41 and the non-skin-facing sheet 42 include SMS nonwoven fabrics (spunbond, meltblown, and spunbond nonwoven fabrics), spunbond nonwoven fabrics, air-through nonwoven fabrics, plastic sheets, perforated plastic sheets, and laminates thereof. The skin-facing sheet 41 and the non-skin-facing sheet 42 are bonded together with an adhesive such as a hot melt adhesive. The plurality of thread-like elastic members 43 are arranged vertically between the skin-facing sheet 41 and the non-skin-facing sheet 42 and are fixed in a stretched state in the width direction. This allows the back waist portion 40 to stretch in the width direction and fit the waist of the wearer. The thread-like elastic members 43 are made of, for example, rubber, spandex, or other elastic materials. As shown in FIG. 2, the thread-like elastic members 43 may be arranged in the back waist portion 40 so that they are not provided in part of the region overlapping the absorbent core 13a (details of which will be described later) of the absorbent main body 10. That is, the thread-like elastic members 43 may be cut midway in the width direction. This makes it possible to prevent the stretching of the thread-like elastic members 43 in the width direction, which is required to fit the back waist portion 40 to the waist, from affecting the positioning of the absorbent core 13a, etc.
[0034] As shown in FIGS. 2 and 3, the absorbent body 10 is configured to include a skin-facing sheet 11, a non-skin-facing sheet 12, and an absorbent body 13.
[0035] The absorbent body 13 includes a liquid-absorbing absorbent core 13a and a core wrap 13b. The absorbent core 13a is configured to capture bodily waste and is a laminate of absorbent materials, such as pulverized pulp, superabsorbent polymer (SAP), or a mixture of these. The absorbent core 13a has a maximum width at both longitudinal ends and is formed into a constricted shape that is recessed inward in the width direction toward the longitudinal center. The core wrap 13b is arranged to cover the skin-facing and non-skin-facing sides of the absorbent core 13a and is, for example, a tissue or nonwoven fabric sheet. The absorbent body 13 is provided in the widthwise center of the absorbent main body 10, spanning substantially the entire longitudinal area except for both longitudinal ends.
[0036] As shown in FIG. 3, the skin-facing sheet 11 includes a top sheet 11a and a side sheet 11b. The top sheet 11a is a liquid-permeable sheet arranged on the skin-facing side so as to cover the absorbent body 13, allowing excrement to pass through toward the absorbent body 13. The top sheet 11a is made of, for example, a liquid-permeable nonwoven fabric. The side sheet 11b is a liquid-impermeable sheet arranged over the entire longitudinal direction, outside the central portion of the absorbent body 13 in the width direction, so as to cover both sides of the top sheet 11a in the width direction. Both longitudinal ends of the side sheet 11b are fixed to the top sheet 11a by bonding with an adhesive or the like. Note that the method of fixing the side sheet 11b to the top sheet 11a is not limited to bonding, and ultrasonic bonding or heat fusion bonding using an embossing roll may also be used. The side sheet 11b is made of, for example, a hydrophobic nonwoven fabric.
[0037] As shown in FIG. 3, a plurality of (e.g., three) thread-like elastic members 116a are provided along the longitudinal direction at the inner end portion of the side sheet 11b in the width direction. Elastic members such as rubber or spandex are used as the thread-like elastic members 116a. The front ends of the thread-like elastic members 116a reach the area of the ventral waistline portion 30, and their rear ends reach the area of the back waistline portion 40. One or more thread-like elastic members 115a are provided along the longitudinal direction at the outer end portion of the side sheet 11b in the width direction. The thread-like elastic members 115a are leg-around elastic members that are stretchable in the longitudinal direction at both ends in the width direction. Elastic members such as rubber or spandex are used as the thread-like elastic members 115a. The front ends of the thread-like elastic members 115a reach the vicinity of the ventral waistline portion 30, and their rear ends reach the vicinity of the back waistline portion 40.
[0038] As shown in Figure 2, the non-skin-facing sheet 12 includes a back sheet 12a and an outer nonwoven fabric 12b. The back sheet 12a is a liquid-impermeable sheet arranged on the non-skin-facing side so as to cover the absorbent body 13, and is configured to prevent excrement from leaking to the outside. The back sheet 12a is made of, for example, a film. The outer nonwoven fabric 12b is a liquid-impermeable sheet arranged on the non-skin-facing side of the back sheet 12a. The outer nonwoven fabric 12b is made of, for example, a hydrophobic nonwoven fabric.
[0039] As shown in FIG. 3, the absorbent body 10 has at least leg stretchable sections 115 and leg side gathers 116 as its functional components.
[0040] The leg stretchable sections 115 have thread-like elastic members 115a, which are stretchable sections that are stretchable in the longitudinal direction, on both sides (both widthwise ends) of the absorbent main body 10. In the leg stretchable sections 115, the thread-like elastic members 115a contract to form leg gathers that improve the fit around the legs of the wearer in the crotch region when in use.
[0041] The leg side gathers 116 are located widthwise inward of the leg stretchable portions 115, have both longitudinal ends fixed, and are configured to stand up by contracting in the longitudinal direction. The leg side gathers 116 include the above-mentioned side sheets 11b. In the leg side gathers 116, both ends of the side sheets 11b are fixed to the top sheet 11a, and the thread-like elastic members 116a contract, forming a pair of leakage-proof cuffs in the crotch region when in use that stand up toward the wearer's skin and prevent body waste from leaking along the surface of the top sheet 11a.
[0042] [Details of the crotch elastic material] As shown in FIG. 2, the pants-type absorbent article 1 includes a plurality of (e.g., four) crotch elastic members 50. The plurality of crotch elastic members 50 are disposed on the absorbent core 13a and extend in the longitudinal direction. Here, "disposed on the absorbent core 13a" means that the crotch elastic members 50 are disposed so as to overlap the absorbent core 13a at least in the thickness direction of the absorbent main body 10. In this embodiment, each crotch elastic member 50 is disposed on the non-skin-facing side of the backsheet 12a of the non-skin-facing sheet 12 and on the skin-facing side of the outer nonwoven fabric 12b, in an area overlapping the absorbent core 13a in the thickness direction. Elastic members such as rubber and spandex are used as the crotch elastic members 50. Alternatively, stretch films or the like may be used as the crotch elastic members 50. The crotch elastic members 50 have a higher elastic modulus than the above-described thread-like elastic members 115a that function as leg-hole elastic members. The crotch elastic member 50 may have a higher elastic modulus than the thread-like elastic members 116a. The elastic modulus is determined by, for example, the thickness of the elastic member multiplied by the magnification.
[0043] The "elastic modulus" referred to here is an elastic coefficient or elastic constant that focuses mainly on the stretching of the pants-type absorbent article 1 in the longitudinal direction, and corresponds to Young's modulus E shown below. E=σ / ε σ: Stress due to stretching of elastic material ε: Strain due to stretching of elastic material
[0044] As shown in FIG. 2, when the absorbent body 10 is unfolded, the effective length in the longitudinal direction of the crotch elastic member 50 is shorter than the length L1 in the longitudinal direction of the portion of the absorbent core 13a that is formed into a constricted shape.
[0045] The multiple crotch elastic members 50 extend in the longitudinal direction so as to straddle a center line BB, which is a folding line of the absorbent core 13a that intersects the longitudinal direction and serves as the lower end of the crotch section when worn. As shown in Fig. 2, the multiple crotch elastic members 50 are arranged biased toward the ventral waistline 30 with respect to the center line BB. That is, when the center line BB is used as the reference, the effective length of the multiple crotch elastic members 50 extending toward the ventral waistline 30 is longer than the effective length of the portion extending toward the back waistline 40. The multiple crotch elastic members 50 may be arranged biased toward either the ventral waistline 30 or the back waistline 40, whichever has a relatively lower contractile force.
[0046] The multiple crotch elastic members 50 are arranged so as not to overlap either the ventral waistline portion 30 or the back waistline portion 40. That is, as shown in Fig. 2, the front end (ventral end) of each crotch elastic member 50 in the longitudinal direction does not reach the area where it overlaps with the ventral waistline portion 30, and the rear end (back end) in the longitudinal direction does not reach the area where it overlaps with the back waistline portion 40. Note that in this embodiment, each crotch elastic member 50 is described as being arranged so as not to overlap either the ventral waistline portion 30 or the back waistline portion 40, but each crotch elastic member 50 may be arranged so as to overlap one of the ventral waistline portion 30 and the back waistline portion 40 but not the other.
[0047] At least one or more crotch elastic members 50 are disposed in each of three equal width regions of the absorbent core 13a. As shown in Fig. 2, the three equal width regions are, for example, regions defined by trisecting lines C1-C1 and C2-C2 that divide the maximum width W10, which is the length between both ends 13x, 13x at the widest portion of the absorbent core 13a in the width direction, into three equal parts. In the example shown in Fig. 2, one crotch elastic member 50 is disposed in the region to the left of the trisecting line C1-C1, two crotch elastic members 50 are disposed in the region between the trisecting line C1-C1 and the trisecting line C2-C2, and one crotch elastic member 50 is disposed in the region to the right of the trisecting line C2-C2. In this embodiment, the region divided into three equal parts in the width direction is described as a region obtained by dividing the maximum width length W10 into three equal parts, as described above, but the region divided into three equal parts in the width direction may also be a region obtained by dividing an area other than the maximum width portion of the absorbent core 13a into three equal parts in the width direction.
[0048] Furthermore, multiple crotch elastic members 50 may be arranged in each of two equal width regions of the absorbent core 13a. As shown in FIG. 2, the two equal width regions are, for example, regions defined by a bisector AA that bisects the maximum width W10, which is the distance between both ends 13x, 13x at the widest portion of the absorbent core 13a in the width direction. In the example shown in FIG. 2, two crotch elastic members 50 are arranged in the region to the left of the bisector AA, and two crotch elastic members 50 are arranged in the region to the right of the bisector AA. Note that multiple crotch elastic members 50 may be arranged evenly (at equal intervals) in the width direction of the absorbent core 13a. By arranging multiple crotch elastic members 50 at equal intervals in this manner, the absorbent core 13a can be pulled up in a plane.
[0049] As described above, the multiple crotch elastic members 50 are arranged in each of three equal widthwise regions, and therefore are also arranged at both widthwise ends. Specifically, at the center line BB, which is the lower end of the crotch section, the outermost widthwise crotch elastic member 50 is arranged toward the widthwise end so that the distance W1 from the outermost widthwise crotch elastic member 50 to the widthwise end of the absorbent core 13a is shorter than the crotch elastic member pitch P1, which is the separation distance between two adjacent crotch elastic members 50, 50 included in the multiple crotch elastic members. Note that the distance W1 refers to the distance from the leftmost crotch elastic member 50 shown in FIG. 2 to the left end of the absorbent core 13a and the distance from the rightmost crotch elastic member 50 shown in FIG. 2 to the right end of the absorbent core 13a. If these distances are different from each other, the distance W1 may be any one of the two values, or the shorter or longer value, or the average of the two values. Furthermore, with regard to the crotch elastic member pitch P1, three patterns are possible in the example shown in FIG. 2, but if these are different values, it may be any one of the values, the value at the shortest pitch, the value at the longest distance, or the average value of the pitches.
[0050] [Pull-up design details] As shown in FIG. 2, a lifting design De is formed in the overlapping region of the absorbent main body 10 and the ventral waistline portion 30, and in the overlapping region of the absorbent main body 10 and the dorsal waistline portion 40, to indicate the pull-up point of the wearer when worn. The lifting design De is, for example, drawn on the back sheet 12a of the absorbent main body 10, and is formed so as to be visible to the wearer when worn. The lifting design De may be any design as long as it can indicate the pull-up point to the wearer (distinguish it from other regions), and may be shown in a color different from other regions, may be shown as a shape such as a square, or may be shown as a simple linear pattern. Furthermore, if the lifting design De includes a linear pattern, the line may be a horizontal line, a vertical line, or a diagonal line.
[0051] Two (a pair) of lifting designs De are formed spaced apart from each other in the width direction, with one lifting design De formed at one end (left end) of the backsheet 12a in the width direction and the other lifting design De formed at the other end (right end) of the backsheet 12a in the width direction. Each lifting design De is formed continuously (in a straight line) along the longitudinal direction from the area where the absorbent main body 10 and the ventral waistline portion 30 overlap to the area where the absorbent main body 10 and the back waistline portion 40 overlap. In other words, the lifting designs De are formed not only in the area where the absorbent main body 10 and the ventral waistline portion 30 (and the back waistline portion 40) overlap, but also over almost the entire longitudinal area of the absorbent main body 10, including the crotch portion and the like.
[0052] In Figure 2, the hatching in the area of the pull-up design De where the absorbent main body 10 and the ventral waistline portion 30 (and the back waistline portion 40) overlap is shown relatively light, and the hatching in areas such as the crotch area is shown relatively dark.This is to express that in the area where the absorbent main body 10 and the ventral waistline portion 30 (and the back waistline portion 40) overlap, the pull-up design De is visible through the ventral waistline portion 30 (or the back waistline portion 40), and therefore the pull-up design De is visible relatively lightly to the wearer.
[0053] The pair of lifting designs De, De, which are spaced apart from each other in the width direction, are arranged on the outside of the plurality of crotch elastic members 50 in the width direction so as to sandwich the plurality of crotch elastic members 50. The separation distance W2 between the pair of lifting designs De, De is set to be no more than twice the separation distance W3 between the outermost crotch elastic members 50 in the width direction included in the plurality of crotch elastic members 50. By making the difference between the separation distance W2 and the separation distance W3 small, at approximately no more than twice, the separation distance between the crotch elastic members 50 and the lifting designs De can be made closer.
[0054] The lifting designs De, De are formed on a longitudinal line of the widest part (the part indicated by the maximum width length W10) of the absorbent core 13a in the width direction. This configuration forms the lifting designs De, De in an area where the absorbent core 13a can be pulled up as a whole surface.
[0055] The lifting designs De, De are formed on the longitudinal end portions 13y of the absorbent core 13a. In this configuration, the lifting designs De, De are formed in areas where the absorbent core 13a itself can be directly pulled up.
[0056] [Pattern dimensions for pants-type absorbent products] The pants-type absorbent article 1 according to this embodiment is, for example, a pants-type disposable diaper for newborns. The pants-type absorbent article 1 is a size (first size) for newborns, and the dimensions of the absorbent main body 10 when stretched are the same as those of other pants-type absorbent articles, for example, of a so-called S size (second size), and the dimensions of the ventral waistband 30 and the dorsal waistband 40 constituting the belt portion 5 when stretched are the same as those of other pants-type absorbent articles. Here, the "other pants-type absorbent article" refers to, for example, a pants-type absorbent article of the same brand name and sub-brand name as the pants-type absorbent article 1, and of another size (for example, S size (second size)) used for infants older than newborns. The "other pants-type absorbent article" here has the same basic configuration as the pants-type absorbent article 1, and may also have an elastic member equivalent to the crotch elastic member 50. Note that the "other pants-type absorbent article" does not necessarily have an elastic member equivalent to the crotch elastic member 50. The pant-type absorbent article 1 is larger than, for example, the "other pant-type absorbent article" of size S in at least one of the number, contraction force, and arrangement area of the crotch elastic members 50. In this way, the pant-type absorbent article 1 has at least one of the number, contraction force, and arrangement area of the crotch elastic members 50 increased, so that the pant-type absorbent article 1 can be used as a pant-type disposable diaper for newborns that is smaller than size S by adjusting the size using the crotch elastic members 50 while using the same paper pattern dimensions as the "other pant-type absorbent article." Note that the "other pant-type absorbent article" may have a different brand name (or sub-brand name) from the pant-type absorbent article 1.
[0057] [Action and effect] Next, the effects of the pants-type absorbent article 1 according to this embodiment will be described.
[0058] The pants-type absorbent article 1 of this embodiment comprises an absorbent main body 10 having a liquid-absorbent absorbent core 13a, a belt portion 5 having a ventral waist portion 30 located at one longitudinal end of the absorbent main body 10 and a dorsal waist portion 40 located at the other longitudinal end of the absorbent main body 10, and a plurality of crotch elastic members 50 arranged on the absorbent core 13a and extending in the longitudinal direction, and at least one or more crotch elastic members 50 are arranged in each of three equal width regions of the absorbent core 13a that intersect the longitudinal direction.
[0059] In the pants-type absorbent article 1 according to the present embodiment, a plurality of crotch elastic members 50 extending in the longitudinal direction are disposed on the absorbent core 13a. With this configuration, when the belt portion 5 is pulled up during the pulling-up action at the time of putting on the garment, the pulling force is easily transmitted to the crotch region including the absorbent core 13a via the crotch elastic members 50. In the pants-type absorbent article 1 according to the present embodiment, one or more crotch elastic members 50 are disposed in each of three equal widthwise regions of the absorbent core 13a (i.e., the central region and the left and right end regions), and the crotch elastic members 50 are disposed over a wide area in the width direction, so that during the pulling-up action, the crotch region including the absorbent core 13a can be pulled up as a whole. As described above, with the pants-type absorbent article 1 according to the present embodiment, the crotch region can be pulled up as a whole during the pulling-up action at the time of putting on the garment, and the occurrence of leakage, etc. can be effectively suppressed.
[0060] The multiple crotch elastic members 50 may be arranged so as to straddle a center line BB, which is a folded line that intersects the longitudinal direction of the absorbent core 13a and becomes the lower end of the crotch when worn. In this way, by arranging the crotch elastic members 50 so as to straddle the center line BB, which becomes the lower end of the crotch, the lower end of the crotch can be pulled up via the crotch elastic members 50 during the pulling-up operation, and the crotch part can be pulled up more effectively.
[0061] The plurality of crotch elastic members 50 may be arranged biased toward the ventral waistline 30 side with respect to the center line BB. With respect to the absorbent core 13a, there are cases where one of the ventral waistline 30 side and the back waistline 40 side is difficult to pull up. In this regard, by arranging the crotch elastic members 50 biased toward the side that is difficult to pull up, of the ventral waistline 30 side and the back waistline 40 side, the side that is difficult to pull up can be pulled up intensively via the crotch elastic members 50. Furthermore, by arranging the crotch elastic members 50 biased toward the ventral waistline 30 side, the fit of the absorbent core 13a near the crotch region can be improved.
[0062] The plurality of crotch elastic members 50 may be arranged biased toward the side of the ventral waistline portion 30 and the back waistline portion 40 that has a relatively low contractile force. The side of the ventral waistline portion 30 and the back waistline portion 40 that has a relatively low contractile force is less likely to be pulled up in conjunction with each other during the pulling-up operation when putting on the garment. In this regard, by arranging the crotch elastic members 50 biased toward the side with a low contractile force, for example, the side with a low contractile force can be more effectively pulled up during the pulling-up operation by focusing on increasing the linkage with the pulling-up operation on the side with a low contractile force.
[0063] The multiple crotch elastic members 50 may be arranged so as not to overlap either the ventral waistline portion 30 or the back waistline portion 40, or may be arranged so as to overlap one of the ventral waistline portion 30 and the back waistline portion 40 but not the other. If the crotch elastic members 50 extend to a region overlapping with the belt portion 5, there is a risk that a force will be applied to the belt portion 5 in a downward direction via the crotch elastic members 50 after wearing. In this regard, by arranging the crotch elastic members 50 so as not to overlap at least both the ventral waistline portion 30 and the back waistline portion 40 that constitute the belt portion 5, even if a force in a downward direction is applied to the crotch elastic members 50, the force in the downward direction is prevented from being strongly transmitted to the belt portion 5, and therefore the belt portion 5 can be effectively prevented from being pulled down.
[0064] The longitudinal center portion of the absorbent core 13a is formed in a constricted shape that is recessed inward in the width direction, and the effective length of the crotch elastic member 50 in the longitudinal direction may be shorter than the length L1 of the constricted portion in the longitudinal direction when the absorber main body 10 is unfolded. By making the effective length of the crotch elastic member shorter than the constricted shape of the longitudinal center portion in this way, the vicinity of the constricted shape of the longitudinal center portion is easily contracted, effectively pulling up the crotch portion, and also, it is possible to appropriately prevent the crotch elastic member 50 from reaching both longitudinal end sides and pulling down the belt portion 5.
[0065] At a center line BB, which is a folding line intersecting the longitudinal direction of the absorbent core 13a and which becomes the lower end of the crotch region when worn, the distance W1 from the outermost crotch elastic member 50 in the width direction included in the plurality of crotch elastic members 50 to the width direction end of the absorbent core 13a may be shorter than the crotch elastic member pitch P1, which is the separation distance between two adjacent crotch elastic members 50, 50 included in the plurality of crotch elastic members 50. With this configuration, the crotch elastic member 50 is located close to the width direction end of the absorbent core 13a, so that the crotch region including the absorbent core 13a can be pulled up as a whole surface during the pulling-up operation.
[0066] The absorbent body 10 has thread-like elastic members 115a at both widthwise ends thereof that function as leg-hole elastic members that are stretchable in the longitudinal direction, and the crotch elastic members 50 may have a higher elastic modulus than the thread-like elastic members 115a. Use of such crotch elastic members 50 increases the contractile force of the crotch area, enabling the crotch area to be pulled up effectively.
[0067] A lifting design De indicating a lifting point when worn may be formed in at least one of the area where the absorbent main body 10 and the ventral waistline portion 30 overlap and the area where the absorbent main body 10 and the back waistline portion 40 overlap. With this configuration, the lifting design is formed in the area where the ventral waistline portion 30 and the absorbent main body 10 overlap, i.e., in the area where a lifting force can be easily transmitted to the absorbent main body 10 (absorbent core 13a) when pulling up the belt portion 5, thereby encouraging the user to properly pull up the crotch part including the absorbent core 13a.
[0068] The lifting design De may be formed on a longitudinal line of the widest part in the width direction of the absorbent core 13a (the part indicated by the maximum width length W10). With this configuration, the lifting design De is formed in an area where the crotch part including the absorbent core 13a can be pulled up as a whole in a pulling action, thereby encouraging the user to properly pull up the crotch part including the absorbent core 13a.
[0069] The lifting design De may be formed on the longitudinal end 13y of the absorbent core 13a. With this configuration, the lifting design De is formed in an area where the absorbent core 13a itself can be directly pulled up, thereby encouraging the user to properly pull up the crotch portion including the absorbent core 13a.
[0070] The lifting design De may be formed continuously along the longitudinal direction from the region where the absorbent main body 10 and the ventral waistline portion 30 overlap to the region where the absorbent main body 10 and the dorsal waistline portion 40 overlap. According to this configuration, the lifting design De is formed continuously, including in the crotch area, which makes it easier for the user to visualize the correct lifting direction.
[0071] A plurality of (a pair of) pull-up designs De may be formed spaced apart in the width direction. With this configuration, it becomes possible to form the pull-up designs De, De at the gripping positions of both hands during the actual pull-up motion, thereby encouraging the user to perform an appropriate pull-up motion.
[0072] The pair of lifting designs De, De may be arranged on the outer sides of the plurality of crotch elastic members 50 in the width direction so as to sandwich the plurality of crotch elastic members 50. With this configuration, the lifting designs De are formed in an area where force can be appropriately transmitted to all of the plurality of crotch elastic members 50, that is, an area where the crotch region including the absorbent core 13a can be pulled up as a whole, thereby encouraging the user to appropriately pull up the crotch region including the absorbent core 13a.
[0073] The separation distance W2 between the pair of lifting designs De, De may be no more than twice the separation distance W3 between the widthwise outermost crotch elastic members 50, 50 included in the plurality of crotch elastic members 50. With this configuration, the separation distance between the crotch elastic member 50 and the lifting design De can be reduced in the width direction, so that when a lifting operation is performed in accordance with the lifting design De, a lifting force can be appropriately transmitted to the crotch elastic member 50, and the crotch region can be effectively pulled up via the crotch elastic member 50.
[0074] Each of the two equal width regions of the absorbent core 13a may be provided with a plurality of crotch elastic members 50. By providing a plurality of crotch elastic members 50 in each of the two equal width regions, a sufficient pulling force can be ensured in each region, and the crotch region including the absorbent core 13a can be pulled up as a whole.
[0075] The pant-type absorbent article 1 is of a first size (e.g., a size for newborns) and has the same dimensions of the absorber main body 10 when stretched as other pant-type absorbent articles of a second size (e.g., a size S), and the same dimensions of the ventral waistline portion 30 and the back waistline portion 40 constituting the belt portion 5 when stretched as other pant-type absorbent articles, and may have at least one of the number, contractile force, and arrangement area of the crotch elastic members 50 greater than those of the other pant-type absorbent articles. With this configuration, the absorber main body 10 and the belt portion 5 use the same paper pattern dimensions as other pant-type absorbent articles of a second size, but by increasing at least one of the number, contractile force, and arrangement area of the crotch elastic members 50, it is possible to provide a pant-type absorbent article of a first size smaller than the second size. In this way, the size of the pant-type absorbent article is adjusted by the crotch elastic members 50, and it is possible to provide a pant-type absorbent article of a shape that fits the size of the wearer while improving the ability to pull up the crotch area with the crotch elastic members 50. The pants-type absorbent article 1 may use the same paper pattern dimensions as other pants-type absorbent articles of a second size (e.g., size S), but, for example, when bonding together materials constituting the absorbent main body 10 and the belt portion 5, the materials may be bonded together so that the dimensions of the finished product (after bonding together materials) when stretched are smaller than the dimensions of the finished product of the second size when stretched. In other words, the bonding positions of the materials may be adjusted so that the dimensions of the finished product (after bonding together materials) when stretched are smaller than the dimensions of the finished product of the second size when stretched.
[0076] [Variations] Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments. For example, although the multiple crotch elastic members 50 have been described as being arranged so as to be biased toward the ventral waistline 30 with respect to the center line BB, the present invention is not limited to this. For example, in cases where the contractile force of the back waistline 40 is relatively low, the crotch elastic members 50A may be arranged so as to be biased toward the back waistline 40 with respect to the center line BB, as in the pants-type absorbent article 1A shown in Fig. 4. By arranging the crotch elastic members 50A so as to be biased toward the back waistline 40, it is possible to improve the ease of pulling up the back body when in a lying position.
[0077] Furthermore, in the above embodiment, the pulling-up design De is described as being continuously formed along the longitudinal direction from the region where the absorbent main body 10 and the ventral waistline portion 30 overlap to the region where the absorbent main body 10 and the back waistline portion 40 overlap, but this is not limited thereto. For example, as in the pants-type absorbent article 1B shown in Fig. 5, the pulling-up designs DeB, DeB, DeB, DeB may be formed only at the four corners of the absorbent main body 10. Note that even in a configuration in which the pulling-up designs DeB are formed only at the four corners, by forming the pulling-up designs DeB on the longitudinal line of the widest part in the width direction of the absorbent core, the crotch portion including the absorbent core can be pulled up over its entire surface during the pulling-up action, and the pulling-up design DeB is formed in a region, which encourages the user to properly pull up the crotch portion including the absorbent core. Furthermore, even in a configuration in which the lifting design DeB is formed only at the four corners, by forming the lifting design DeB at the longitudinal end of the absorbent core, the lifting design DeB is formed in an area where the absorbent core itself can be directly pulled up, thereby encouraging the user to properly pull up the crotch area including the absorbent core. Also, in the above embodiment, it has been explained that the lifting design De may be formed at the longitudinal end 13y of the absorbent core 13a, but in such a configuration, the lifting design De may also be formed continuously in the width direction. With such a configuration, the visibility of the lifting design De can be further improved. [Explanation of symbols]
[0078] 1, 1A, 1B...pants-type absorbent article, 5...belt portion, 10...absorbent main body, 13a...absorbent core, 30...ventral waist portion, 40...dorsal waist portion, 50, 50A...crotch elastic member, 115a...thread-like elastic member (leg elastic member).
Claims
1. an absorbent body having a liquid-absorbing absorbent core; a belt portion having a ventral waist portion located at one end side of the absorbent main body in the longitudinal direction and a dorsal waist portion located at the other end side of the absorbent main body in the longitudinal direction; a plurality of crotch elastic members disposed on the absorbent core and stretchable in the longitudinal direction; a first size, the absorbent main body has the same dimension when stretched as another pants-type absorbent article of a second size larger than the first size, and the belt portion has the same dimension when stretched as another pants-type absorbent article of a second size larger than the first size, A pants-type absorbent article in which at least one of the number of the crotch elastic members, the contractile force, and the layout area is greater than that of the other pants-type absorbent articles.
2. The first size is a size for a newborn, 2. The pant-type absorbent article of claim 1, wherein the second size is a size used for infants older than newborns.