CN114305878A - Absorbent article - Google Patents

Abstract

The invention provides an absorptive article which can easily discharge the moisture absorbed by an absorptive core to the outside. An absorbent article (1) having an absorbent body (10), the absorbent body (10) having a liquid-absorbent core (11) and an air-permeable film (13a) provided at a position on the non-skin side of the absorbent core (11), wherein the absorbent article has hydrophilic nonwoven fabrics (32, 42) at a position on the non-skin side of the air-permeable film (13a), and the absorbent core (11), the air-permeable film (13a), and the hydrophilic nonwoven fabrics (32, 42) at least partially overlap when viewed from the thickness direction of the absorbent body (10).

Description

Absorbent article

Technical Field

The present invention relates to an absorbent article.

Background

Conventionally, absorbent articles such as disposable diapers having liquid-absorbent cores have been widely used. As an example of such an absorbent article, a technique is known in which a breathable film is provided on the non-skin side of an absorbent core so that moisture such as urine absorbed by the absorbent core does not leak as liquid, but passes through the breathable film as vapor and transpires to the outside (non-skin side) of the diaper. For example, patent document 1 discloses a pants-type disposable diaper having an absorbent core 56 (absorbent element 50), a liquid impermeable sheet 70 having liquid impermeability and moisture permeability disposed on the non-skin side of the absorbent core 56, and a crotch outer sheet 12 disposed on the non-skin side of the liquid impermeable sheet 70 and exposed to the outer surface of the product.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open No. 2008-253285

Disclosure of Invention

Problems to be solved by the invention

In a conventional absorbent article, as disclosed in patent document 1, an outer sheet member (crotch outer sheet 12) constituting an outer package of the product is generally provided on the non-skin side of an air-permeable film (liquid-impermeable sheet 70). The exterior sheet member is generally formed of a hydrophobic nonwoven fabric such as a meltblown nonwoven fabric, a point-bonded nonwoven fabric, or a through-air nonwoven fabric.

However, if a hydrophobic outer sheet member is provided on the non-skin side of the breathable film, it may be difficult to effectively transpire moisture such as urine absorbed by the absorbent core to the outside of the absorbent article. For example, there is a case where water vapor that has passed through the air-permeable film from the absorbent core and moved from the skin side to the non-skin side is blocked from further movement to the non-skin side by the hydrophobic outer covering sheet member, and water is likely to be accumulated between the outer covering sheet member and the air-permeable film. In this case, since moisture remains inside the absorbent article without being discharged to the outside, there is a possibility that the moisture may cause stuffiness and skin troubles, and may cause a wearer to feel uncomfortable.

The present invention has been made in view of the above-described conventional problems, and an object thereof is to provide an absorbent article that can easily discharge moisture absorbed by an absorbent core to the outside.

Means for solving the problems

The main invention for achieving the above object is an absorbent article having an absorbent body having a liquid-absorbent core and an air-permeable film provided at a position on the non-skin side of the absorbent core, characterized in that the absorbent article has a hydrophilic nonwoven fabric at a position on the non-skin side of the air-permeable film, and the absorbent core, the air-permeable film and the hydrophilic nonwoven fabric at least partially overlap when viewed in the thickness direction of the absorbent body.

Other features of the present invention will be apparent from the description of the present specification and the accompanying drawings.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, an absorbent article can be provided that can easily discharge the moisture absorbed by the absorbent core to the outside.

Drawings

Fig. 1 is a schematic perspective view of a diaper 1.

Fig. 2 is a plan view of the diaper 1 in an unfolded and extended state.

Fig. 3 is a schematic sectional view taken along line a-a of fig. 2.

Fig. 4A is a plan view of the absorbent main body 10, and fig. 4B is a schematic sectional view of the absorbent main body 10.

Fig. 5A, 5B, and 5C are diagrams illustrating a mechanism of discharging water from the absorbent body 10 in the region B of fig. 3.

Fig. 6A is a schematic plan view showing a state in which the pants-type diaper 1 is in an extended state and viewed from the front side in the front-rear direction. Fig. 6B is a schematic plan view showing a state in which the pants-type diaper 1 is in an extended state and viewed from the rear side in the front-rear direction.

Fig. 7 is a schematic sectional view taken along line C-C of fig. 6A.

Fig. 8A and 8B are views for explaining a method of attaching the waist elastic member 35 to the front waist portion 30 using the welded portion 60.

Fig. 9A is a plan view of the diaper 2 in an unfolded and extended state. Fig. 9B is a schematic sectional view taken along line D-D of fig. 9A.

Fig. 10A is a plan view of the diaper 3 in an unfolded and extended state. Fig. 10B is a schematic sectional view taken along line E-E of fig. 10A.

Fig. 11A is a plan view of the diaper 4 in an unfolded and extended state. Fig. 11B is a schematic sectional view taken along line F-F of fig. 11A.

Description of the reference numerals

1. Diapers (absorbent articles, pants-type diapers) (embodiment 1); 2. diapers (absorbent articles, pants-type diapers) (embodiment 2); 3. diapers (absorbent articles, pants-type diapers) (embodiment 3); 4. diapers (absorbent articles, tape-type diapers) (embodiment 4); 10. an absorbent main body; 11. an absorbent core; 11b, a core cladding sheet; 11c, a narrowing; 11s, slit portions; 12. a top sheet; 13. a bottom sheet; 13a, a liquid impermeable sheet; 13b, an exterior sheet; 15. a leakage preventing wall portion; 16. a leakage preventing wall elastic member; 17. a leg elastic member; 18. a side panel; 20. a waist member; 21. a skin side sheet (hydrophobic nonwoven fabric); 22. a non-skin side sheet (hydrophilic nonwoven fabric); 25. an exterior sheet (hydrophilic nonwoven fabric); 26. a hook and loop fastener; 26f, surface fastener; 27. a target sheet; 30. a front waist portion; 30sw, side; 31. a skin side sheet (hydrophobic nonwoven fabric); 32. a non-skin side sheet (hydrophilic nonwoven fabric); 32f, a folded-back portion; 32h, an opening part; 35. a waist elastic member; 36. a skin patch; 40. a rear waist portion; 40b, a hip cover; 40sw, lateral; 41. a skin side sheet (hydrophobic nonwoven fabric); 42. a non-skin side sheet (hydrophilic nonwoven fabric); 42f, a folded-back portion; 42h, a hole opening part; 45. a waist elastic member; 46. a skin patch; 47. a bending elastic member; 50. a side engaging portion; 60. a fusion part; 60s, welding part pair; BH. Opening the waist; LH, opening of leg girth; CL, center position (longitudinal ).

Detailed Description

At least the following matters will be made clear from the description of the present specification and the drawings.

An absorbent article having an absorbent body having a liquid-absorbent core and an air-permeable film provided at a position on the non-skin side of the absorbent core, characterized in that the absorbent article has a hydrophilic nonwoven fabric at a position on the non-skin side of the air-permeable film, and the absorbent core, the air-permeable film and the hydrophilic nonwoven fabric at least partially overlap when viewed in the thickness direction of the absorbent body.

In such an absorbent article, in the region where the absorbent core, the breathable film, and the hydrophilic nonwoven fabric overlap in the thickness direction, the hydrophilic nonwoven fabric having high hydrophilicity facilitates the transfer of water to the non-skin side in the thickness direction. That is, the transfer of water to the non-skin side can be promoted, and water can be easily discharged from the inside to the outside of the diaper.

In the absorbent article, it is preferable that the absorbent article includes an absorbent main body including the absorbent core, the absorbent article includes an exterior member including a front waist portion joined to one side in a longitudinal direction of the absorbent main body and a rear waist portion joined to the other side in the longitudinal direction of the absorbent main body, the absorbent article includes a pair of side joining portions that join both left and right side portions of the front waist portion and the rear waist portion to each other in a state where the absorbent main body is folded in two at a predetermined position in the longitudinal direction, and a hydrophilic nonwoven fabric is provided at least partially in the exterior member.

According to such an absorbent article, in a so-called 3-piece pants-type absorbent article including an absorbent main body and a front waist portion and a rear waist portion (outer covering member) disposed on the non-skin side of the absorbent main body, it is possible to promote the transfer of moisture from the skin side to the non-skin side and easily discharge moisture from the inside to the outside of the absorbent article at a portion where the absorbent core, the air-permeable film, and the hydrophilic nonwoven fabric are overlapped in the thickness direction.

In the absorbent article, it is preferable that the absorbent article includes an absorbent main body including the absorbent core, the absorbent article includes an outer covering member provided on a non-skin side of the absorbent main body and integrally formed continuously from one side to the other side in a longitudinal direction of the absorbent main body, the absorbent article includes a pair of side joining portions connecting both side portions in a left-right direction of the one side in the longitudinal direction of the outer covering member and both side portions in a left-right direction of the other side in the longitudinal direction of the outer covering member to each other in a state where the absorbent main body is folded in two at a predetermined position in the longitudinal direction, and a hydrophilic nonwoven fabric is provided at least partially on the outer covering member.

According to such an absorbent article, in a so-called two-piece pants-type absorbent article including an absorbent main body and an integral exterior member disposed on the non-skin side of the absorbent main body, in a portion where the absorbent core, the breathable film, and the hydrophilic nonwoven fabric are overlapped in the thickness direction, it is possible to promote the transfer of moisture from the skin side to the non-skin side, and it is possible to easily discharge moisture from the inside to the outside of the absorbent article.

In the absorbent article, it is preferable that an area of a portion where the absorbent core, the air-permeable film, and the hydrophilic nonwoven fabric overlap in a region below the lower end of the side joint section is larger than an area of a portion where the absorbent core, the air-permeable film, and the hydrophilic nonwoven fabric overlap in a region above the lower end of the side joint section when viewed in the thickness direction.

According to such an absorbent article, the area of the region where the absorbent core and the hydrophilic nonwoven fabric overlap can be increased in the region located in the crotch of the wearer (crotch region). Therefore, moisture such as urine absorbed by the absorbent core (skin side) can be easily transferred to the hydrophilic nonwoven fabric side (non-skin side) over a wide range of the crotch region. This makes it possible to prevent the wearer from feeling uncomfortable in the crotch portion.

In the absorbent article, the whole of the breathable film is preferably overlapped with the hydrophilic nonwoven fabric when viewed from the thickness direction.

In such an absorbent article, moisture in urine or the like absorbed by the absorbent core, which has passed through the breathable film from the skin side to the non-skin side as water vapor, is likely to migrate to the hydrophilic nonwoven fabric provided on the non-skin side over the entire region of the breathable film. This makes it easier to promote the movement of moisture from the skin side to the non-skin side in the thickness direction, and makes it possible to prevent moisture from remaining inside the absorbent article.

In the absorbent article, it is preferable that the outer covering member has an elastic member that stretches and contracts in the left-right direction, and a stress of a central portion of the elastic member in the left-right direction of the absorbent core is smaller than a stress of both side portions of the elastic member in the left-right direction of the absorbent core.

In such an absorbent article, the contraction force generated by the elastic member is less likely to act on the center portion of the absorbent core in the lateral direction, and the absorbent main body and the exterior member are more likely to maintain a planar shape. Therefore, the laminated structure of the sheet members in the thickness direction is easily maintained in the central portion, and the movement of moisture in the thickness direction is not easily inhibited. Thus, the moisture such as urine absorbed by the absorbent core on the skin side is transferred to the hydrophilic nonwoven fabric on the non-skin side, and the moisture can be easily discharged to the outside of the absorbent core.

In the absorbent article, it is preferable that the absorbent article includes an absorbent main body including the absorbent core, the absorbent article includes an exterior member provided on a non-skin side of the absorbent main body and integrally and continuously formed from one side to the other side in a longitudinal direction of the absorbent main body, a pair of fastening tapes is provided at one end portion of the exterior member in the longitudinal direction, and a hydrophilic nonwoven fabric is provided at least partially on the exterior member.

According to such an absorbent article, in a so-called belt-type absorbent article which has an absorbent main body and an exterior member disposed on the non-skin side of the absorbent main body and which is configured to wear the absorbent article on the body of a wearer using a pair of fastening tapes provided on the exterior member, it is possible to promote the transfer of moisture from the skin side to the non-skin side in a portion where the absorbent core, the air-permeable film, and the hydrophilic nonwoven fabric are overlapped in the thickness direction, and it is possible to easily discharge moisture from the inside to the outside of the absorbent article.

In the absorbent article, the outer covering member preferably has a hydrophobic nonwoven fabric having a lower hydrophilicity than the hydrophilic nonwoven fabric at a position closer to the skin than the hydrophilic nonwoven fabric.

According to such an absorbent article, in the exterior member, the moisture is easily transferred from the hydrophobic nonwoven fabric side to the hydrophilic nonwoven fabric side by the hydrophilic gradient generated between the hydrophobic nonwoven fabric and the hydrophilic nonwoven fabric. That is, it becomes easy to smoothly transfer moisture from the skin side to the non-skin side. Therefore, moisture such as urine can be easily discharged to the outside of the absorbent article.

In the absorbent article, the hydrophilic nonwoven fabric is preferably provided on the outermost skin side of the exterior member.

According to such an absorbent article, the hydrophilic nonwoven fabric disposed on the most non-skin side of the outer covering member serves as an interface with the atmosphere, and therefore, the moisture transferred from the absorbent core and contained in the hydrophilic nonwoven fabric can be easily evaporated into the atmosphere. This makes it easier to discharge water to the outside of the absorbent article, and makes it possible to reduce the wearer's discomfort.

In the absorbent article, it is preferable that the absorbent article has a left-right direction, a width of the hydrophilic nonwoven fabric in the left-right direction is larger than a width of the air-permeable film in the left-right direction, and the width of the air-permeable film in the left-right direction is equal to or larger than the width of the absorbent core in the left-right direction.

According to such an absorbent article, moisture (water vapor) can be moved from the entire absorbent core in the left-right direction to the non-skin side through the breathable film. In addition, moisture permeates the breathable film and is easily absorbed by the hydrophilic nonwoven fabric on the non-skin side. Therefore, moisture can be more effectively discharged from the inner side (skin side) to the outer side (non-skin side) of the absorbent article.

In the absorbent article, it is preferable that the absorbent article has a portion where the absorbent core and the hydrophilic nonwoven fabric overlap and a portion where the absorbent core and the hydrophilic nonwoven fabric do not overlap when viewed in the thickness direction.

According to such an absorbent article, it is possible to efficiently discharge moisture such as urine to the outside of the absorbent article at a portion where the absorbent core and the hydrophilic nonwoven fabric overlap. On the other hand, in the portion where the absorbent core and the hydrophilic nonwoven fabric do not overlap, moisture such as sweat of the wearer can be transferred to the hydrophilic nonwoven fabric side and discharged to the outside of the absorbent article. Therefore, the problem of stuffiness and the like when the absorbent article is worn can be further reduced.

In the absorbent article, it is preferable that the absorbent article has a slit portion penetrating the absorbent core in the thickness direction, and the absorbent article has a portion where the slit portion, the breathable film, and the hydrophilic nonwoven fabric overlap when viewed in the thickness direction.

According to such an absorbent article, since the air-permeable film and the hydrophilic nonwoven fabric are provided on the non-skin side of the slit portion of the absorbent core in which moisture such as urine is likely to accumulate, the moisture accumulated in the slit portion can be transferred from the skin side to the non-skin side, and can be made to transpire easily to the outside. Therefore, by providing the slit portion, the absorbent core can be easily deformed along the body shape of the wearer, and the discomfort of the wearer can be suppressed from being generated by the stuffiness.

In the absorbent article, the breathable film preferably has a moisture permeability of 1000g/m²24h or more and 3500g/m²24h or less.

According to such an absorbent article, the moisture permeability is 1000g/m²When the time is 24 hours or more, water vapor can easily permeate through the breathable film, and moisture can easily transpire from the inner side (skin side) to the outer side (non-skin side) of the absorbent article. On the other hand, if the moisture permeability is 3500g/m²When the time is 24 hours or less, excessive permeation of water vapor through the breathable film can be suppressed, and excessive absorption of water by the hydrophilic nonwoven fabric provided on the outer side (non-skin side) can be suppressed. Therefore, when the absorbent article is worn, a proper amount of water can be discharged, and the hydrophilic nonwoven fabric on the outer side can be inhibited from being wet, so that the wearer can be less likely to feel uncomfortable.

In the embodiment 1, the following embodiments are not to be considered in all respects

The absorbent article of the present invention is exemplified by a disposable diaper (hereinafter also referred to as "diaper 1"). However, the absorbent article of the present invention also includes sanitary napkins, pantiliners, and other absorbent articles.

< Structure of diaper 1 >

Fig. 1 is a schematic perspective view of a diaper 1. Fig. 2 is a plan view of the diaper 1 in an unfolded and extended state. Fig. 3 is a schematic sectional view taken along line a-a of fig. 2. The "stretched state" of the diaper 1 means a state in which the entire diaper 1 (the entire product) is stretched without wrinkles, specifically, a state in which the dimensions of the respective members constituting the diaper 1 (for example, the absorbent main body 10, the waist member 20, and the like described later) are equal to or close to the dimensions of the members alone.

The diaper 1 is a disposable diaper having a pants-type shape in a natural state, and in the pants-type state of fig. 1, the diaper 1 has a vertical direction, a horizontal direction, and a front-rear direction which intersect each other, and has a waist opening BH and a pair of leg openings LH and LH. The upper side in the up-down direction corresponds to the waist opening BH side, and the lower side corresponds to the crotch side. The front side in the front-rear direction corresponds to the abdominal side of the wearer, and the rear side corresponds to the back side of the wearer. In addition, in the developed state of fig. 2, the diaper 1 has a longitudinal direction and a lateral direction intersecting each other. The longitudinal direction is a direction along the up-down direction in fig. 1, and corresponds to the longitudinal direction of the absorbent main body 10. The lateral direction is a direction along the left-right direction in fig. 1. As shown in fig. 3, the direction in which the materials constituting the diaper 1 are stacked is defined as the thickness direction. The side in contact with the skin of the wearer in the thickness direction is referred to as the skin side, and the opposite side is referred to as the non-skin side.

The diaper 1 includes a liquid-absorbent main body 10 that absorbs excrement, and a waist member 20 disposed on the non-skin side of the absorbent main body 10. The waist member 20 is an exterior member constituting an exterior package of the diaper 1, and has a front waist portion 30 corresponding to a front portion of the diaper 1 and a rear waist portion 40 corresponding to a rear portion of the diaper 1. That is, the diaper 1 of embodiment 1 is a so-called 3-piece pants-type diaper having as a 1 st member an absorbent main body 10 which is brought into close contact with the crotch of a wearer and absorbs excrement such as urine, a 2 nd member a front waist portion 30 which covers the abdominal portion of the wearer, and a 3 rd member a rear waist portion 40 which covers the back portion of the wearer.

In the developed state of fig. 2, the absorbent main body 10 is laid between the front waist portion 30 and the rear waist portion 40 in a state where they are arranged in parallel with each other with a space in the longitudinal direction, and the respective end portions 10ea and 10eb in the longitudinal direction (longitudinal direction) of the absorbent main body 10 are joined and fixed to the skin side of the respective closest waist portions 30 and 40, respectively, and the outer shape of the diaper 1 is substantially H-shaped in plan view. From this state, the absorbent body 10 is folded in two with the longitudinal center position CL as the folded position. The front waist portion 30 and the rear waist portion 40 facing each other in the folded state are joined and coupled to each other at the side portions 30sw and 40sw on both sides in the left-right direction, thereby forming a pair of joined portions 50, 50. That is, the front waist portion 30 and the rear waist portion 40 are annularly formed by the pair of side joint portions 50, 50. The side joint portion 50 is formed by a known joining method such as welding or bonding. As a result, the diaper 1 is formed in a pants-type state with the waist opening BH and the pair of leg openings LH and LH shown in fig. 1.

(absorbent body 10)

Fig. 4A is a plan view of the absorbent main body 10, and fig. 4B is a schematic sectional view of the absorbent main body 10. The absorbent main body 10 has an absorbent core 11 for absorbing excretory fluid, a top sheet 12 disposed on the skin side of the absorbent core 11 in the thickness direction, and a bottom sheet 13 disposed on the non-skin side of the absorbent core 11. However, the absorbent main body 10 may have a sheet member other than the above-described sheet member. For example, a second sheet (not shown) may be provided between the top sheet 12 and the absorbent core 11 in the thickness direction.

The absorbent core 11 is a member that absorbs and retains excretory fluid such as urine, and is formed of liquid absorbent fibers such as pulp fibers mixed with a Super Absorbent Polymer (SAP), for example. The outer peripheral surface of the absorbent core 11 may be covered with a liquid-permeable sheet member (core wrap sheet 11b) such as tissue paper or nonwoven fabric. The absorbent core 11 of the present embodiment has a narrowed portion 11c having a narrowed width in the left-right direction between the front side end and the rear side end in the longitudinal direction, and has a substantially hourglass shape in plan view as shown in fig. 4A. The narrowed portion 11c is a portion which is sandwiched between the legs of the wearer when the diaper 1 is worn, and the length of this portion in the right-left direction becomes shorter (the width becomes narrower), whereby the absorbent core 11 becomes easy to fit the crotch of the wearer.

Further, the absorbent core 11 is provided with a slit portion 11s penetrating the absorbent core 11 in the thickness direction. The slit portion 11s is formed in a substantially rectangular shape extending in the longitudinal direction (longitudinal direction), and is provided at 1 in the central portion in the lateral direction (left-right direction) of the absorbent core 11. However, the shape and the number of the slit portions 11s are not limited to those shown in fig. 4A and 4B. The slit portion 11s may not be provided in the absorbent core 11.

The top sheet 12 is a liquid-permeable sheet, and for example, a hydrophilic air-through nonwoven fabric, a spunbond nonwoven fabric, or the like is used. In the present embodiment, as shown in fig. 4B, both side portions in the left-right direction of the top sheet 12 are folded back to the non-skin side to roll in the absorbent core 11.

The bottom sheet 13 has a two-layer structure, and includes a liquid-impermeable sheet 13a and an exterior sheet 13b disposed on the non-skin side of the liquid-impermeable sheet 13 a. As the liquid impermeable sheet 13a, a sheet member having liquid impermeability and moisture permeability is used. For example, a microporous breathable resin film having a plurality of fine pores in a sheet mainly composed of a resin such as polyethylene or polypropylene can be used. In the present specification, the liquid-impermeable sheet 13a is also referred to as a "breathable film". That is, the breathable film is a sheet member that is permeable to water vapor and air, but not to liquid. On the other hand, a hydrophobic nonwoven fabric having flexibility is used as the outer sheet 13 b. For example, a through-air nonwoven fabric, a spunbond nonwoven fabric, or the like can be used.

A pair of leakage preventing wall portions 15 are provided on both side portions in the left-right direction of the absorbent main body 10 along the longitudinal direction (the longitudinal direction of the absorbent main body 10). In the present embodiment, the leakage preventing wall 15 is formed of the outer sheet 13b described above. Specifically, a pair of leakage preventing wall portions 15 are formed by extending a part of the outer covering sheet 13B outward from both ends of the absorbent core 11 in the left-right direction (lateral direction) and bending the same toward the skin side at a plurality of locations as shown in fig. 4B. The leakage preventing wall elastic member 16 such as an elastic thread is attached to the skin-side end portion (distal end portion) of the leakage preventing wall portion 15 in a state of being extended in the longitudinal direction (the longitudinal direction of the absorbent main body 10). When the diaper 1 is worn, the leakage preventing wall 15 is raised toward the skin of the wearer due to the stretchability exhibited by the leakage preventing wall elastic member 16, and is fitted to the crotch of the wearer.

The leg hole elastic members 17 such as elastic threads are attached to both side portions in the left-right direction of the absorbent main body 10 in a state of being extended in the longitudinal direction (the longitudinal direction of the absorbent main body 10). When the diaper 1 is worn, the side portions of the absorbent main body 10 contract due to the stretchability exhibited by the leg hole elastic members 17, and the absorbent main body is easily attached along the leg holes of the wearer.

(front side waist body 30)

As shown in fig. 3, the front waistline portion 30 includes a skin side sheet 31 disposed closest to the skin side in the thickness direction, a non-skin side sheet 32 laminated on the non-skin side of the skin side sheet 31 adjacent to the skin side sheet 31, and a waistline elastic member 35 provided between the skin side sheet 31 and the non-skin side sheet 32 in the thickness direction. The front waist portion 30 as an exterior member of the diaper 1 basically has a double-layer structure including the skin-side sheet 31 and the non-skin-side sheet 32, but the front waist portion 30 may have a structure including 3 or more layers in part of the skin-side sheet 36 described later, for example.

The skin-side sheet 31 and the non-skin-side sheet 32 are sheet members having a rectangular shape in plan view as shown in fig. 2, and are formed of, for example, SMS nonwoven fabric or the like. In the diaper 1, the sheet member (nonwoven fabric) constituting the non-skin side sheet 32 has higher hydrophilicity than the sheet member (nonwoven fabric) constituting the skin side sheet 31. That is, the skin side sheet 31 is formed of a nonwoven fabric having low hydrophilicity, and the non-skin side sheet 32 is formed of a nonwoven fabric having higher hydrophilicity than the skin side sheet 31. Hereinafter, the nonwoven fabric forming the skin side sheet 31 is also referred to as "hydrophobic nonwoven fabric", and the nonwoven fabric forming the non-skin side sheet 32 is also referred to as "hydrophilic nonwoven fabric". The "hydrophilicity" of the nonwoven fabric will be described later.

Further, a plurality of opening portions 32h are provided on the surface of the non-skin side sheet 32 as shown in the partially enlarged view of fig. 2. The opening portion 32h is a through hole that penetrates the non-skin side sheet 32 in the thickness direction, and the air permeability of the front waist portion 30 can be improved by providing this opening portion 32 h. Further, the opening hole portion 32h is disposed so as to be visually recognizable from the non-skin surface side of the front waist portion 30, and thus the user can easily think that the front waist portion 30 has good air permeability. Each opening portion 32h may have a circular shape with a diameter of about 1mm, for example, but the shape and arrangement (number and pattern) of the opening portions 32h can be changed as appropriate. In the diaper 1, the skin-side sheet 31 is not provided with through-holes corresponding to the hole portions 32 h.

The front waist portion 30 of the present embodiment has a folded-back portion 32f, and the folded-back portion 32f is formed by folding back an upper end portion (a front end portion in the longitudinal direction) of the non-skin side sheet 32 from the non-skin side to the skin side and from the front side in the longitudinal direction to the rear side. By covering a part (upper end portion) of the skin side sheet 31 with the folded-back portion 32f, the upper end edge of the skin side sheet 31 can be prevented from sinking into the skin of the wearer. However, the folded-back portion 32f may not necessarily be provided.

A plurality of the waistline elastic members 35 are arranged in a vertical direction between the skin side sheet 31 and the non-skin side sheet 32, and the waistline elastic members 35 are attached between the skin side sheet 31 and the non-skin side sheet 32 in a state of being extended in the horizontal direction. The front waistline portion 30 is attached to the abdomen-side waistline of the wearer by the stretchability exhibited by the waistline elastic member 35.

The waist elastic member 35 can be attached using an adhesive such as a hot melt adhesive. For example, the waistline elastic member 35 can be attached by applying a hot-melt adhesive to the waistline elastic member 35, stretching the same at a predetermined stretching ratio, and sandwiching the same between the skin side sheet 31 and the non-skin side sheet 32. That is, the skin side sheet 31 and the non-skin side sheet 32 are joined by an adhesive via the waist elastic member 35. The waist elastic member 35 may be attached by applying an adhesive to the skin side sheet 31 and the non-skin side sheet 32, or the waist elastic member 35 may be attached by a welding method using a welding portion 60 described later.

The front waist portion 30 may have a skin surface sheet 36. As shown in fig. 3, the skin-facing sheet 36 is a sheet member disposed so as to cover the upper end (the front end in the longitudinal direction) of the absorbent main body 10 from the skin side, and functions as a covering sheet. This can prevent the upper end edge of the absorbent main body 10 from falling into the skin of the wearer when the diaper 1 is worn. The skin sheet 36 is formed of, for example, SMS nonwoven fabric. The skin sheet 36 may not necessarily be provided.

In the front waistline portion 30 of the present embodiment, in the case where a sheet member is provided at a position closer to the skin side than the skin side sheet 31 or at a position closer to the non-skin side than the non-skin side sheet 32, each sheet is disposed so as to cover only a part of the skin side sheet 31 and the non-skin side sheet 32. For example, the skin sheet 36 in fig. 3 is provided to cover only a part of the skin side sheet 31 on the skin side, and at least a part of the skin side sheet 31 is exposed to the skin side of the wearer.

(rear waist body 40)

The rear waist portion 40 has substantially the same structure as the front waist portion 30. That is, the rear waistline portion 40 includes a skin side sheet 41 disposed on the skin side most in the thickness direction, a non-skin side sheet 42 laminated on the non-skin side of the skin side sheet 41 adjacent to the skin side sheet 41, and a waistline elastic member 45 provided between the skin side sheet 41 and the non-skin side sheet 42 in the thickness direction. Similarly to the front waist portion 30, the rear waist portion 40 may have an opening portion 42h, a folded portion 42f, a skin surface sheet 46, and the like (see fig. 2 and 3). The structures of the respective members are substantially the same as those of the front waist portion 30, and therefore, the description thereof is omitted.

On the other hand, the external shape of the rear waist portion 40 is different from the external shape of the front waist portion 30. Specifically, as shown in fig. 2, the rear waist portion 40 includes a hip cover 40b having a substantially trapezoidal shape at a position below the side joining portion 50 (side portion 40sw) in the vertical direction. The hip cover 40b is a portion whose width in the left-right direction is narrowed from the upper side toward the lower side in the up-down direction, and whose outer edge is curved. By providing the hip cover 40b, the rear waist portion 40 can widely cover the hip of the wearer when the diaper 1 is worn.

The hip cover 40b is provided with a curved elastic member 47 such as an elastic string as shown in fig. 2. The curved elastic member 47 is attached between the skin side sheet 41 and the non-skin side sheet 42 in a state of being stretched along the end edge portion of the hip cover 40b, and the hip cover 40b of the rear waist portion 40 is easily attached to the hip of the wearer and the hip cover 40b is not easily rolled up from the hip by the stretchability exhibited by the curved elastic member 47 when the diaper 1 is worn.

< hydrophilicity with respect to sheet Member >

Here, the hydrophilicity of the sheet member will be explained. In the diaper 1, hydrophobic nonwoven fabrics are used as the skin side sheets 31 and 41 constituting the waist member 20 (the front waist portion 30 and the rear waist portion 40) as the exterior member and the exterior sheet 13b of the absorbent main body 10. On the other hand, hydrophilic nonwoven fabrics having higher hydrophilicity than hydrophobic nonwoven fabrics are used as the non-skin side sheets 32 and 42 constituting the waist member 20.

The hydrophilic nonwoven fabric of the present embodiment is a nonwoven fabric having improved hydrophilicity by performing a treatment (hydrophilic treatment) of adhering a predetermined oil agent to a hydrophobic nonwoven fabric. As the oil agent used for the hydrophilic treatment, for example, a commercially available oil agent effective as an antistatic agent for fibers, such as an anionic oil agent, a nonionic oil agent, and a mixture thereof, can be used. By feeding these oil agents into the oil tank and supplying the oil using an oil supply roller or the like, the hydrophilicity of the hydrophobic nonwoven fabric can be improved, and a hydrophilic nonwoven fabric can be obtained. However, the hydrophilic nonwoven fabric may be formed by other methods. For example, a hydrophilic nonwoven fabric may be obtained by producing a nonwoven fabric using fibers having high hydrophilicity.

In the present embodiment, the whole nonwoven fabric constituting the non-skin side sheets 32 and 42 is subjected to hydrophilic treatment, and the hydrophilicity of the whole sheet members is improved. However, the hydrophilicity of only a part of the region of each sheet member may be increased. For example, a sheet member having a portion with high hydrophilicity and a portion with low hydrophilicity in part may be formed by performing hydrophilic treatment or the like only on a part of the non-skin side sheet 32.

The hydrophilicity of the sheet member can be evaluated by measuring the contact angle when the ion-exchanged water is brought into contact with the surface of the sheet member. Specifically, when the contact angle between the hydrophilic nonwoven fabric and ion-exchanged water is smaller than the contact angle between the hydrophobic nonwoven fabric and ion-exchanged water, the hydrophilicity of the hydrophilic nonwoven fabric is higher than the hydrophilicity of the hydrophobic nonwoven fabric. The hydrophilic nonwoven fabric (e.g., the non-skin side sheet 32) used in the present embodiment preferably has a contact angle with ion-exchanged water of less than 90 °, more preferably 50 ° or less. On the other hand, the hydrophobic nonwoven fabric (skin-side sheet 31) preferably has a contact angle with ion-exchanged water of 90 ° or more, and more preferably 120 ° or more.

For example, the contact angle can be measured by the following method using a contact angle meter MCA-J manufactured by synechia interface science co. First, ion-exchanged water (about 20 picoliters) was dropped onto the surface of the fiber constituting the sheet member (measurement target sheet) to be measured, and immediately thereafter, the contact angle was measured using the contact angle meter. The measurement is performed at a plurality of sites (for example, 5 sites or more) on the surface of the measurement sheet, and the average value of these sites is defined as the contact angle. The measurement environment temperature was set to 22 ℃.

The contact angle may be measured by imaging the measurement sheet on which the ion-exchanged water has been dropped from the cross-sectional direction of the measurement sheet, analyzing the imaged image, and measuring the angle formed between the droplet of the ion-exchanged water and the measurement sheet.

< absorption and discharge of moisture with respect to the absorbent body 10 >

In the diaper 1, the absorbent body 10 (absorbent core 11) absorbs excretory fluid (moisture) such as urine, and the absorbed moisture is appropriately discharged to the outside of the diaper 1, thereby suppressing the water retention capacity (amount of moisture that can be absorbed) of the absorbent core 11 from reaching a limit, and making it easy to maintain the water absorption function and the interior of the absorbent body 10 less prone to becoming stuffy.

Fig. 5A to 5C are diagrams illustrating a mechanism of discharging water from the absorbent body 10 in the region B of fig. 3. Fig. 5A to 5C show a state in which the absorbent core 11, the liquid-impermeable sheet 13a (air-permeable film), the outer sheet 13b (hydrophobic nonwoven fabric), the skin side sheet 31 (hydrophobic nonwoven fabric), and the non-skin side sheet 32 (hydrophilic nonwoven fabric) are laminated in this order from the skin side toward the non-skin side in the thickness direction.

When urine or the like is excreted when the diaper 1 is worn, the water such as the urine is absorbed by the absorbent core 11. Then, as shown in fig. 5A, a part of the absorbed moisture permeates the liquid-impermeable sheet 13a (breathable film) from the skin side to the non-skin side in the thickness direction as water vapor, and moves to the exterior sheet 13b and the skin side sheet 31 side. Although the exterior sheet 13b and the skin side sheet 31 are hydrophobic nonwoven fabrics, since voids are formed by a plurality of fibers constituting the nonwoven fabrics, a part of moisture (water vapor) is drawn into the exterior sheet 13b and the skin side sheet 31 by a capillary phenomenon generated in the voids.

As shown in fig. 5B, moisture introduced into the exterior sheet 13B and the skin side sheet 31 is then transferred to the non-skin side sheet 32 adjacent to the skin side in the thickness direction. Since the non-skin side sheet 32 is a hydrophilic nonwoven fabric having higher hydrophilicity than those of the exterior sheet 13b and the skin side sheet 31, the moisture contained in the exterior sheet 13b and the skin side sheet 31 is easily transferred to the hydrophilic nonwoven fabric side (the non-skin side sheet 32 side) due to the gradient of hydrophilicity formed between the hydrophilic nonwoven fabric and the hydrophobic nonwoven fabric.

As shown in fig. 5C, the moisture (water vapor) transferred to the non-skin side sheet 32 transpires to the outside (the atmospheric side in fig. 5C) from the non-skin side surface of the non-skin side sheet 32. In the diaper 1, the non-skin side sheet 32 is disposed on the outermost surface (non-skin side) of the absorbent main body 10. That is, the non-skin side surface of the non-skin side sheet 32 serves as an interface with the atmosphere. Therefore, the moisture contained in the non-skin side sheet 32 can be effectively transpired from the non-skin side surface to the outside of the diaper 1 over a wide range. However, it is not necessary to dispose the hydrophilic nonwoven fabric on the entire surface of the exterior member on the non-skin side. For example, another member (e.g., a belt member) may be provided in a part of the non-skin side surface of the exterior member.

In general, in an absorbent article such as a conventional disposable diaper, a sheet member having high hydrophilicity (the non-skin side sheet 32 in the diaper 1) is not provided on the non-skin side of the absorbent core and the air-permeable film (the liquid-impermeable sheet 13a in the diaper 1). Therefore, the water vapor that has permeated the breathable film is likely to accumulate in the portion of the sheet member (hydrophobic nonwoven fabric) having low hydrophilicity provided on the non-skin side. That is, the structure in which moisture is easily retained between the breathable film (corresponding to the liquid-impermeable sheet 13a) and the hydrophobic nonwoven fabric (the exterior sheet 13b and the skin side sheet 31) may cause stuffiness of the diaper and the like.

In contrast, in the diaper 1 of the present embodiment, a hydrophilic nonwoven fabric (non-skin side sheet 32) having high hydrophilicity is provided on the non-skin side of the breathable film (liquid-impermeable sheet 13a) and the hydrophobic nonwoven fabric (outer covering sheet 13b and skin side sheet 31). Therefore, moisture is attracted to the hydrophilic nonwoven fabric side (non-skin side) having higher hydrophilicity, and moisture is less likely to accumulate between the breathable film (corresponding to the liquid-impermeable sheet 13a) and the hydrophobic nonwoven fabric (the outer sheet 13b, the skin side sheet 31). That is, the moisture absorbed by the absorbent core 11 is easily transferred from the skin side to the non-skin side in the thickness direction.

In the diaper 1, the hydrophobic nonwoven fabrics (the outer sheet 13b and the skin side sheet 31) are provided between the liquid-impermeable sheet 13a (breathable film) and the non-skin side sheet 32 (hydrophilic nonwoven fabric) in the thickness direction, but even if the hydrophobic nonwoven fabrics are not provided, the above-described moisture discharge can be performed. At least, the air-permeable film may be disposed at a position on the non-skin side of the absorbent core, and the sheet member (hydrophilic nonwoven fabric) having high hydrophilicity may be disposed at a position on the non-skin side of the air-permeable film. With such a configuration, the movement of the moisture in the thickness direction as described above can be promoted, and the moisture such as urine absorbed by the absorbent core can be effectively discharged to the outside.

In this way, in the diaper 1, the absorbent core, the air-permeable film, and the hydrophilic nonwoven fabric are arranged to overlap in the thickness direction, and thereby, the movement of moisture in the thickness direction is easily promoted in the region where the 3 members overlap. That is, moisture is easily discharged from the inside (absorbent body) of the diaper 1 to the outside. Therefore, moisture is less likely to remain inside the diaper 1, and the moisture absorption capacity of the absorbent core 11 is less likely to reach the limit, thereby facilitating maintenance of the water absorption function. Further, discomfort such as stuffiness can be reduced when the diaper 1 is worn by the wearer.

Fig. 6A is a schematic plan view showing a state in which the pants-type diaper 1 is in an extended state and viewed from the front side in the front-rear direction. Fig. 6B is a schematic plan view showing a state in which the pants-type diaper 1 is in an extended state and viewed from the rear side in the front-rear direction. As shown in fig. 6A and 6B, in the diaper 1, the length (width) W13 in the left-right direction of the liquid-impermeable sheet 13a (breathable film) is greater than the length (width) W11 in the left-right direction of the absorbent core 11 (W11 < W13). In fig. 6A, the length (width) W32 in the left-right direction of the non-skin side sheet 32 (hydrophilic nonwoven fabric) is greater than the length (width) W13 in the left-right direction of the liquid-impermeable sheet 13a (breathable film) (W13 < W32). In fig. 6B, the length (width) W42 in the left-right direction of the non-skin side sheet 42 (hydrophilic nonwoven fabric) is greater than the length (width) W13 in the left-right direction of the liquid-impermeable sheet 13a (breathable film) (W13 < W42).

As shown in fig. 6A and 6B, the entire absorbent core 11 in the left-right direction is overlapped with the liquid impermeable sheet 13a (air-permeable film), so that moisture (water vapor) can be moved from the entire absorbent core 11 in the left-right direction to the non-skin side through the air-permeable film. Further, the entire liquid-impermeable sheet 13a (breathable film) in the left-right direction overlaps the non-skin side sheets 32 and 42 (hydrophilic nonwoven fabric), and thus moisture that has passed through the breathable film is easily absorbed by the hydrophilic nonwoven fabric on the non-skin side. This facilitates the transfer of water from the entire region of the absorbent core 11 in the lateral direction to the hydrophilic nonwoven fabric, and allows the water to be effectively discharged from the inside (skin side) to the outside (non-skin side) of the diaper 1.

In addition, according to the above-described relationship, the diaper 1 has a portion where the non-skin side sheets 32 and 42 (hydrophilic nonwoven fabric) and the absorbent core 11 overlap and a portion where they do not overlap when viewed from the thickness direction. In the portion where the absorbent core 11 and the hydrophilic nonwoven fabric are superposed (the region indicated by W11 in fig. 6A and 6B), as described above, the moisture such as urine absorbed by the absorbent core 11 can be efficiently discharged to the outside of the diaper 1.

On the other hand, in the region where the absorbent core 11 and the hydrophilic nonwoven fabric do not overlap, moisture such as sweat generated from the body of the wearer can be transferred to the hydrophilic nonwoven fabric side. Fig. 7 is a schematic sectional view taken along line C-C of fig. 6A. Fig. 7 is a view corresponding to fig. 3, and shows a cross section of a portion where the absorbent core 11 and the hydrophilic nonwoven fabric do not overlap. In fig. 7, when the wearer sweats, the sweat having transmitted through the top sheet 12 of the absorbent main body 10 passes through the liquid-impermeable sheet 13a (breathable film) as water vapor, and is transferred to the non-skin side sheet 32 (hydrophilic nonwoven fabric) through the outer sheet 13b and the skin side sheet 31, and finally transpires to the outside of the diaper 1. That is, moisture can be transferred from the skin side to the non-skin side of the diaper 1, and moisture can be discharged from the surface of the hydrophilic nonwoven fabric to the non-skin side. Therefore, in the diaper 1, moisture such as sweat attached to the skin of the wearer can be discharged to the outside in addition to moisture such as urine absorbed by the absorbent core 11. This makes it possible to further reduce the occurrence of stuffiness when the diaper 1 is worn.

Further, a hydrophobic nonwoven fabric is disposed between the hydrophilic nonwoven fabric and the air-permeable film in the thickness direction at least in a part of a region where the hydrophilic nonwoven fabric does not overlap with the absorbent core 11. For example, in the case of fig. 7, an exterior sheet 13b and a skin side sheet 31 (both of hydrophobic nonwoven fabrics) are provided between a non-skin side sheet 32 (hydrophilic nonwoven fabric) and a liquid-impermeable sheet 13a (breathable film). In this case, as described above, the hydrophilic gradient between the hydrophilic nonwoven fabric and the hydrophobic nonwoven fabric makes it easy for water to migrate from the hydrophobic nonwoven fabric side to the hydrophilic nonwoven fabric side. That is, moisture is easily transferred from the skin side to the non-skin side. Therefore, moisture such as sweat can be more easily discharged to the outside of the diaper 1.

The waist member 20 of the diaper 1 is provided with the waist elastic members 35, 45 and the curved elastic member 47 which expand and contract in the left-right direction, but these elastic members do not locally exhibit stretchability in the region overlapping the absorbent main body 10. For example, in fig. 6A and 6B, the waist elastic members 35 and 45 and the curved elastic member 47 are partially cut at the center portion in the left-right direction of the absorbent main body 10, and thereby the waist elastic members contract from the cut portions to both sides in the left-right direction (hereinafter, the regions across both ends of the absorbent main body 10 in the left-right direction are also referred to as "both side portions"). Therefore, the contraction force acting on the center portion in the left-right direction of the absorbent main body 10 by the elastic members 35, 45, 47 is weaker than the contraction force acting on both side portions in the left-right direction by the elastic members 35, 45, 47. In other words, the elastic members 35, 45, 47 have smaller stresses in the center portion in the left-right direction of the absorbent main body 10 than the elastic members 35, 45, 47 have in the both side portions in the left-right direction of the absorbent main body 10. The elastic members 35, 45, and 47 may not necessarily be cut at the center portion in the left-right direction of the absorbent main body 10, and may be formed so that the stress at the center portion in the left-right direction is weaker than that at both side portions in the left-right direction.

With such a configuration, the contraction force of the elastic members 35, 45, and 47 is less likely to act on the center portion in the left-right direction of the absorbent main body 10 (absorbent core 11), and wrinkles or the like are less likely to form on the surfaces of the absorbent main body 10 and the waistline member 20, and the planar shape is more likely to be maintained. Therefore, the stacked structure of the sheet members in the thickness direction as described in fig. 5A to 5C is easily maintained, and the movement of moisture in the thickness direction is not easily hindered. This makes it possible to transfer moisture such as urine absorbed by the absorbent core 11 on the skin side to the hydrophilic nonwoven fabric on the non-skin side, and to transpire the moisture at a position closer to the non-skin side than the hydrophilic nonwoven fabric.

The stress of the elastic member can be measured as follows using, for example, an Autograph type tensile tester (e.g., AG-1KN1) manufactured by shimadzu corporation. First, in a state where the waist member 20(30, 40) of the diaper 1 is extended to such an extent that the surface thereof is not wrinkled, the dimension in the left-right direction of the region to be measured (the central portion and both side portions in the left-right direction of the absorbent main body 10) in the region where the elastic members 35, 45, 47 are arranged is measured, and then the region to be measured is cut at the dimension by a cutter to obtain a sample. Next, one end of the sample was clamped to a fixed chuck and the other end was clamped to a movable chuck, and the sample was stretched to a size of about 90% of the initial dimension at a speed of 300mm/min, and then, the sample was contracted to a size of about 75% of the initial dimension in reverse, and the tensile load (N) of each sample at that time was obtained and converted into stress (N/mm) per unit length (mm) as stress.

The absorbent body 10 of the diaper 1 has a slit portion 11s penetrating the absorbent core 11 in the thickness direction. The slit portion 11s and the hydrophilic nonwoven fabric have a portion overlapping each other when viewed in the thickness direction. For example, in the diaper 1, in the region indicated by the hatched region in fig. 6B, the slit portion 11s overlaps the hydrophilic nonwoven fabric (the non-skin side sheet 42 of the rear waist portion 40).

Since the rigidity at the slit portion 11s in the absorbent core 11 is low, the absorbent core 11 can be easily deformed along the body shape of the wearer. On the other hand, since the slit portion 11s is formed in a groove shape, moisture such as excrement is likely to accumulate or move, and a wearer may feel uncomfortable. On the other hand, in the diaper 1, since the hydrophilic nonwoven fabric is provided on the non-skin side of the slit portion 11s, the structure in which moisture is easily transferred from the skin side to the non-skin side and the moisture is easily transpired at a position closer to the non-skin side (outer side of the diaper 1) than the hydrophilic nonwoven fabric is as described above. Therefore, while maintaining good fit of the absorbent core 11 to the body, moisture can be easily discharged to the outside, and discomfort to the wearer can be suppressed.

In the diaper 1, the liquid-impermeable sheet 13a (breathable film) preferably has a moisture permeability of 1000g/m2 · 24h or more and 3500g/m2 · 24h or less. If the moisture permeability is 1000g/m2 · 24h or more, water vapor can easily permeate the liquid-impermeable sheet 13a, and moisture can easily transpire from the inner side (skin side) to the outer side (non-skin side) of the diaper 1. On the other hand, if the moisture permeability is 3500g/m2 · 24h or less, excessive permeation of water vapor through the liquid-impermeable sheet 13a can be suppressed, and excessive absorption of water by the hydrophilic nonwoven fabric provided on the outer side (non-skin side) can be suppressed. Therefore, when the diaper 1 is worn, a proper amount of moisture can be discharged and the hydrophilic nonwoven fabric on the outside can be inhibited from being wet, so that the wearer can be less likely to feel uncomfortable.

The moisture permeability can be measured in accordance with JIS Z0208 (method for measuring moisture permeability of a moisture-proof packaging material by the method for measuring moisture permeability of a moisture-proof packaging material test (moisture permeability test method)). First, a plurality of samples (3 or more circular samples having a diameter about 10mm larger than the inner diameter of the moisture permeable cup used for measurement) were prepared from the liquid impermeable sheet 13 a. Next, a moisture absorbent JIS K8123 [ calcium chloride (anhydrous)]Put into a moisture permeable area of 25cm²The sample is mounted in the moisture permeable cup, sealed with a wax sealing agent, left standing in a constant temperature and humidity chamber for 16 hours or more, taken out, the temperature is allowed to be balanced with the room temperature, and the mass is measured by an electronic scale or the like. Thereafter, the specimen is again allowed to stand in the constant temperature and humidity chamber at constant intervals (for example, every 24 hours)Time) was repeated to determine the mass increase by repeating the weighing operation of the electronic balance, and the test was continued until the mass increase became constant within 5%. Then, the moisture permeability is calculated for each sample by the following equation (1), and a value obtained by rounding to two significant figures by JIS Z8401 (numerical pill め square (numerical rounding)) is taken as the moisture permeability of the liquid-impermeable sheet 13 a.

Moisture permeability of 240 m/(t.s) · (1)

s: moisture permeable area (cm)²)

t: the sum of the time (h) of the last two weighing intervals of the test

m: the sum of the added masses (mg) of the last two weighing intervals of the test run

< modification of method for attaching waist elastic members 35, 45 >

In the above embodiment, the waistline elastic members 35, 45 are attached to the waistline member 20 by an attachment method using a hot melt adhesive or the like, but the method of attaching the waistline elastic members 35, 45 is not limited thereto. For example, the waistline elastic members 35, 45 may be attached to the waistline member 20 by a welding method such as ultrasonic welding. Since ultrasonic welding is a known technique, the description of ultrasonic welding will be omitted in this specification.

Fig. 8A and 8B are views for explaining a method of attaching the waist elastic member 35 to the front waist portion 30 using the welded portion 60. In the present modification, the waistline elastic member 35 is attached to the front waistline portion 30 by a plurality of welded portions 60, 60 … … disposed in a dispersed manner in the left-right direction and the up-down direction. Each of the welded portions 60 is formed into a substantially rectangular shape by ultrasonic welding, and they join the skin side sheet 31 and the non-skin side sheet 32 of the front waist portion 30 in the thickness direction. The waistline elastic member 35 is attached to the front waistline portion 30 by sandwiching the waistline elastic member 35 from both sides in the vertical direction by 1 pair of fusion-bonded portions 60s composed of two fusion-bonded portions 60, 60 adjacent in the vertical direction.

As shown in fig. 8A, the pair of fusion-bonded portions 60 and 60 constituting the fusion-bonded portion pair 60s are arranged with an interval GH60 in the vertical direction. The distance GH60 is set to be the same as the diameter d35t of the waist elastic member 35 in the state of being stretched to a predetermined stretch ratio or slightly larger than the diameter d35t (GH 60. gtoreq.d 35 t). That is, the waistline elastic member 35 in the stretched state is disposed between the pair of welded portions 60s in the up-down direction.

Next, as shown in fig. 8B, when the waistline elastic member 35 is relaxed from the stretched state, the waistline elastic member 35 contracts in the left-right direction and expands in the up-down direction, and the diameter d35 in its natural state becomes larger than the interval GH60 in the up-down direction of the pair of welded portions 60s (d35 > GH 60). Thereby, the waistline elastic member 35 is pressed in the vertical direction by the welding portions 60, 60. As a result, the waist elastic member 35 is attached to the front waist portion 30.

In the pants-type diaper 1 of fig. 1, the waist elastic members 35(45) are in a natural state relaxed from the extended state. In the pants-type diaper 1, the waist elastic member 35(45) is joined to the front waist portion 30 (the rear waist portion 40) by the side joining portions 50, 50 at both side portions in the right and left direction. Therefore, even if the front waist portion 30 (the rear waist portion 40) is stretched in the left-right direction when the diaper 1 is worn, the waist elastic members 35(45) do not fall off from the waist member 20.

In the 2 nd embodiment, the following embodiments are also provided

In embodiment 2, a pants-type diaper 2 (hereinafter also referred to as "diaper 2") having a structure partially different from that of embodiment 1 will be described. Fig. 9A is a plan view of the diaper 2 in an unfolded and extended state. Fig. 9B is a schematic sectional view taken along line D-D of fig. 9A. Note that each direction (for example, a longitudinal direction, a lateral direction, and the like) in fig. 9A and 9B is the same as each direction defined in embodiment 1.

The diaper 2 of embodiment 2 includes a liquid-absorbent main body 10 and a waist member 20 as an exterior member joined to the non-skin side of the absorbent main body 10. As shown in fig. 9A and 9B, the waist member 20 of the diaper 2 is continuously and integrally formed in the longitudinal direction (the longitudinal direction of the absorbent main body 10). That is, the diaper 2 is a so-called two-piece disposable diaper including two components, i.e., an absorbent body 10 and an outer cover member (a waistline member 20). Hereinafter, a portion of the outer covering member (waist member 20) of the diaper 2 on the front side in the longitudinal direction with respect to the center position CL will be described as a front waist portion 30, and a portion on the rear side with respect to the center position CL will be described as a rear waist portion 40 (see fig. 9A).

When the diaper 2 in the developed state of fig. 9A is formed into a pants type, the absorbent body 10 and the waist member 20 are folded in two with the longitudinal center position CL as a folded position. The front waist portion 30 and the rear waist portion 40 facing each other in the folded state are joined and connected to each other via the side portions 30sw and 40sw on both sides in the left-right direction, thereby forming a pair of joined portions 50, 50. As a result, similarly to the diaper 1 of fig. 1, the diaper 2 is in a pants-type state having a waist opening BH and a pair of leg openings LH and LH.

In the diaper 2, the basic structure and function of the absorbent main body 10 are substantially the same as those of the diaper 1 of embodiment 1, and therefore, the description thereof is omitted. However, the backsheet 13 of the diaper 2 may have only the liquid-impermeable sheet 13a (breathable film) and no outer sheet 13 b. This is because the diaper 2 is provided with the waistline member 20 over the entire non-skin side surface of the absorbent main body 10, and the waistline member 20 functions as an exterior sheet of the absorbent main body 10. Therefore, the bottom sheet 13 of the absorbent body 10 of the diaper 2 does not need to be provided with a sheet member corresponding to the outer sheet 13B of the diaper 1 (see fig. 9B).

The waistline member 20 includes a skin side sheet 21, a non-skin side sheet 22 laminated adjacent to the skin side sheet 21 on the non-skin side of the skin side sheet 21, and waistline elastic members 35, 45 (see fig. 9B) arranged between the skin side sheet 21 and the non-skin side sheet 22 in the thickness direction. The skin side sheet 21 is a hydrophobic nonwoven fabric similar to the skin side sheets 31 and 41 of the diaper 1. The non-skin side sheet 22 is a hydrophilic nonwoven fabric similar to the non-skin side sheets 32 and 42 of the diaper 1. That is, in the diaper 2, the non-skin side sheet 22 is a nonwoven fabric having higher hydrophilicity than the skin side sheet 21. Similarly to the diaper 1, the waist elastic members 35 and 45 are formed of elastic threads or the like, and are attached between the skin-side sheet 21 and the non-skin-side sheet 22 in a state of being stretched in the left-right direction.

The diaper 2 according to embodiment 2 can also provide the same effects as those of the diaper 1. For example, the diaper 2 has a portion where the absorbent core 11, the air-permeable film (liquid-impermeable sheet 13a), and the hydrophilic nonwoven fabric (non-skin side sheet 22) overlap when viewed in the thickness direction. In the portion where the absorbent core 11, the breathable film, and the hydrophilic nonwoven fabric are superposed, as described in fig. 5A to 5C, the movement of moisture from the skin side to the non-skin side in the thickness direction is facilitated, and the moisture can be easily discharged from the inside (the absorbent core 11) to the outside of the diaper 2. In addition, the diaper 2 has basically the same features as the diaper 1 described in embodiment 1.

In the diaper 2, the area of the region where the absorbent core 11 and the hydrophilic nonwoven fabric (non-skin side sheet 22) overlap in the region below the lower end 50eb of the side joining section 50 in the vertical direction is larger than the area of the region where the absorbent core 11 and the hydrophilic nonwoven fabric (non-skin side sheet 22) overlap in the region above the lower end 50eb of the side joining section 50 in the vertical direction (see fig. 9A). That is, when the diaper 2 is worn, the area of the region where the absorbent core 11 and the hydrophilic nonwoven fabric (non-skin side sheet 22) overlap is large in the region (crotch region) located in the crotch of the wearer below the lower end 50eb of the side joining section 50.

Therefore, in the diaper 2, the moisture such as urine absorbed by the absorbent core 11 can be easily discharged to a position on the non-skin side (outside the diaper 2) of the hydrophilic nonwoven fabric over a wide range of the crotch region. This makes the crotch less likely to become stuffy and uncomfortable for the wearer.

In the case of fig. 9A, the whole air-permeable film (liquid-impermeable sheet 13a) is overlapped with the hydrophilic nonwoven fabric (non-skin side sheet 22) when viewed from the thickness direction. Therefore, moisture in urine or the like absorbed by the absorbent core 11, which has passed through the air-permeable film from the skin side to the non-skin side as water vapor, is likely to migrate to the hydrophilic nonwoven fabric provided on the non-skin side over the entire area of the air-permeable film. This facilitates the transfer of moisture from the skin side to the non-skin side in the thickness direction, and makes it possible to prevent moisture from remaining inside the diaper 2. However, as described above, the effect of discharging moisture to the outside of the diaper 2 can be obtained if the absorbent core 11, the air-permeable film (liquid-impermeable sheet 13a), and the hydrophilic nonwoven fabric (non-skin side sheet 22) are at least partially overlapped, and it is not necessarily the case that the entire air-permeable film (liquid-impermeable sheet 13a) is overlapped with the hydrophilic nonwoven fabric (non-skin side sheet 22).

In the 3 rd embodiment, the term "first" means that the first component is not moved to the second component

In embodiment 3, a pants-type diaper 3 (hereinafter also referred to as "diaper 3") having a structure partially different from that of the above-described embodiment will be described. Fig. 10A is a plan view of the diaper 3 in an unfolded and extended state. Fig. 10B is a schematic sectional view taken along line E-E of fig. 10A. Note that each direction (for example, a longitudinal direction, a lateral direction, and the like) in fig. 10A and 10B is the same as each direction defined in embodiment 1.

The diaper 3 of embodiment 3 includes a liquid-absorbent main body 10 and a waistline member 20 as an exterior member joined to the non-skin side of the absorbent main body 10. As shown in fig. 10A and 10B, the waist member 20 of the diaper 3 is continuously and integrally formed in the longitudinal direction (the longitudinal direction of the absorbent main body 10). That is, the skin-side sheet 21 is an integral sheet member continuous from one end portion to the other end portion in the longitudinal direction. On the other hand, the non-skin side sheet 32 (front non-skin side sheet) disposed on the front side in the longitudinal direction and the non-skin side sheet 42 (rear non-skin side sheet) disposed on the rear side in the longitudinal direction are constituted as different sheet members that are discontinuous in the longitudinal direction. A diaper having such a structure is also referred to as a simple 3-piece type disposable diaper. In the following, a portion of the outer covering member (waist member 20) of the diaper 3 on the front side of the center position CL in the longitudinal direction is described as the front waist portion 30, and a portion on the rear side of the center position CL is described as the rear waist portion 40 (see fig. 10A).

When the diaper 3 in the developed state of fig. 10A is formed into a pants type, the absorbent body 10 and the waist member 20 are folded in two with the longitudinal center position CL as a folded position. The front waist portion 30 and the rear waist portion 40 facing each other in the folded state are joined and connected to each other via the side portions 30sw and 40sw on both sides in the left-right direction, thereby forming a pair of joined portions 50, 50. As a result, similarly to the diaper 1 of fig. 1, the diaper 3 is in a pants-type state having a waist opening BH and a pair of leg openings LH and LH.

In the diaper 3, the basic structure and function of the absorbent main body 10 are substantially the same as those of the absorbent main body 10 of the diaper 2 according to embodiment 2, and therefore, the description thereof is omitted.

The front waist portion 30 of the outer covering member (waist member 20) of the diaper 3 has: a skin side sheet 21 extending from one end side (ventral side) to the other end side (dorsal side) in the longitudinal direction on the skin side in the thickness direction; a non-skin side sheet 32 that is laminated on the non-skin side of the skin side sheet 21 adjacent to the skin side sheet 21 on the front side (ventral side) in the longitudinal direction; and a waistline elastic member 35 disposed between the skin side sheet 21 and the non-skin side sheet 32 in the thickness direction. The rear waist portion 40 includes a skin side sheet 21 common to the front waist portion 30, a non-skin side sheet 42 laminated on the non-skin side of the skin side sheet 21 adjacent to the skin side sheet 21 on the rear side (back side) in the longitudinal direction, and a waist elastic member 45 disposed between the skin side sheet 21 and the non-skin side sheet 42 in the thickness direction.

The skin side sheet 21 is a hydrophobic nonwoven fabric similar to the skin side sheets 31 and 41 of the diaper 1. The non-skin side sheets 32 and 42 are hydrophilic nonwoven fabrics similar to the non-skin side sheets 32 and 42 of the diaper 1. That is, in the diaper 3, the non-skin side sheets 32 and 42 are nonwoven fabrics having higher hydrophilicity than the skin side sheet 21. Similarly to the diaper 1, the waist elastic members 35 and 45 are formed of elastic threads or the like, and are attached between the skin side sheet 21 and the non-skin side sheets 32 and 42 in a state of being stretched in the left-right direction

The diaper 3 of embodiment 3 can also provide the same effects as those of the diaper 1 and the diaper 2. For example, in the diaper 3, the absorbent core 11, the air-permeable film (liquid-impermeable sheet 13a), and the hydrophilic nonwoven fabric (non-skin side sheets 32, 42) are superposed in the region surrounded by the dashed line portion in fig. 10B when viewed from the thickness direction. In the portion where the absorbent core 11, the breathable film, and the hydrophilic nonwoven fabric are superposed, as described in fig. 5A to 5C, the movement of moisture in the thickness direction from the skin side to the non-skin side is facilitated, and the moisture can be easily discharged from the inside (the absorbent core 11) to the outside of the diaper 3. In addition, the diaper 3 basically has substantially the same features as the diaper 2 described in embodiment 2.

Embodiment 4 ═ th ═ embodiment ═ 4 ═ embodiment ═ 4 ═ embodiment ═ embodiment ═ may be used

In embodiment 4, a "belt-type diaper" (hereinafter, also referred to as "diaper 4") different from the "pants-type diaper" described in embodiments 1 to 3 will be described as an example of an absorbent article. Fig. 11A is a plan view of the diaper 4 in an unfolded and extended state. Fig. 11B is a schematic sectional view taken along line F-F of fig. 11A. Note that each direction (for example, the longitudinal direction, the lateral direction, and the like) in fig. 11A and 11B is the same as each direction defined in embodiment 1.

As shown in fig. 11A and 11B, the diaper 4 includes an absorbent core 11 that absorbs excrement, a liquid-permeable top sheet 12 positioned on the skin side of the absorbent core 11, a liquid-impermeable sheet 13a positioned on the non-skin side of the absorbent core 11, an outer-covering sheet 25 positioned on the non-skin side of the liquid-impermeable sheet 13a, and a pair of side sheets 18 joined to the skin side of the top sheet 12 at both side portions in the left-right direction of the top sheet 12. Leg elastic members 17 (e.g., elastic threads) that stretch and contract in the longitudinal direction are disposed on both side portions of the diaper 4 in the lateral direction.

The absorbent core 11, the top sheet 12, and the liquid-impermeable sheet 13a of the diaper 4 are parts corresponding to the absorbent main body 10 in the diaper 1, and they have the same functions as the absorbent core 11, the top sheet 12, and the liquid-impermeable sheet 13a constituting the absorbent main body 10 of the diaper 1, respectively. For example, the liquid-impermeable sheet 13a is a breathable film that can transmit moisture such as urine absorbed by the absorbent core 11 as water vapor.

The outer sheet 25 of the diaper 4 is an outer member corresponding to the waist member 20 of the diaper 1, and the outer sheet 25 is formed of a hydrophilic nonwoven fabric similarly to the non-skin side sheets 33, 43 constituting the waist member 20 of the diaper 1. The outer covering member of the diaper 4 may have the same structure as the waist member 20 of the diaper 1. For example, a hydrophobic nonwoven fabric (not shown in fig. 11B) may be provided on the skin side of the exterior sheet 25 made of a hydrophilic nonwoven fabric, and the exterior member of the diaper 4 may be constituted by two sheet members.

For convenience of description, a portion of the diaper 4 located forward of the center position CL in the longitudinal direction is referred to as a front waist portion 30, and a portion located rearward of the center position CL is referred to as a rear waist portion 40 (see fig. 11A).

The pair of side sheets 18 are made of a liquid-permeable nonwoven fabric similar to the top sheet 12, and a leakage preventing wall elastic member 16 such as an elastic string which can expand and contract in the longitudinal direction is provided at the inner end in the lateral direction of the side sheet 18. When the diaper 4 is worn, the laterally inner end portions of the side sheets 18 are raised toward the skin of the wearer by the contraction force exerted by the leakage preventing wall elastic members 16, and the leakage preventing wall portions 15 are formed in the same manner as in the diaper 1.

A pair of fastening tapes 26 extending to both outer sides in the left-right direction are provided on the back side (rear waist portion 40) in the longitudinal direction of the diaper 4. Further, a target sheet 27 for engaging the hook and loop fastener 26 when the diaper 4 is worn is provided on the non-skin side surface of the abdomen side (front waist portion 30) in the longitudinal direction of the diaper 4. A surface fastener 26f having a plurality of hook members (not shown) is provided on the skin-side surface of the free end side (outer side in the left-right direction) of the fastening tape 26. The target sheet 27 is a member capable of engaging with the surface fastener 26f (hook member) of the surface fastener 26, and is formed of, for example, nonwoven fabric.

When the diaper 4 is worn, for example, the diaper 4 in the developed state shown in fig. 11A is disposed in the crotch portion of the wearer, the front waist portion 30 is attached to the abdomen side portion of the wearer, and the rear waist portion 40 is attached to the back side portion (hip portion) of the wearer. Then, the pair of surface fasteners 26, 26 are wound from the back side to the abdomen side along the waist of the wearer, and the surface fastener 26f is engaged with the target sheet 27 on the abdomen side of the wearer. This enables the waist opening BH and the pair of leg openings LH and LH to be formed substantially in the same manner as the diaper 1, and enables the position of the diaper 4 to be fixed with respect to the body (crotch portion) of the wearer.

The diaper 4 may not necessarily be provided with the target sheet 27. For example, instead of disposing the target sheet 27 on the non-skin side surface of the exterior sheet 25, the diaper 4 may be worn by directly engaging the surface fastener 26f with the nonwoven fabric constituting the exterior sheet 25.

The diaper 4 of embodiment 4 can also provide the same effects as those of the diaper 1. For example, in the diaper 4, the entire region of the absorbent core 11 overlaps with the breathable film (the liquid-impermeable sheet 13a) and the hydrophilic nonwoven fabric (the outer sheet 25) when viewed in the thickness direction. In the portion where the absorbent core 11, the breathable film, and the hydrophilic nonwoven fabric are superposed, moisture is likely to move from the skin side to the non-skin side in the thickness direction, and moisture can be easily discharged from the inside (the absorbent core 11) of the diaper 4 to the outside. Otherwise, the diaper 4 has basically the same features as the diaper 1 described in embodiment 1.

Other embodiments are also possible

Although the embodiments of the present invention have been described above, the above embodiments are intended to facilitate understanding of the present invention, and are not intended to limit and explain the present invention. It is to be understood that the present invention can be modified and improved without departing from the gist thereof, and the present invention includes equivalents thereof.

Claims (13)

1. An absorbent article having an absorbent body having a liquid-absorbent core and an air-permeable film provided at a position on the non-skin side of the absorbent core, the absorbent article being characterized in that,

the absorbent article has a hydrophilic nonwoven fabric at a position on the non-skin side of the breathable film,

the absorbent core, the breathable film, and the hydrophilic nonwoven fabric at least partially overlap when viewed from the thickness direction of the absorbent main body.

2. The absorbent article according to claim 1,

the absorbent article has an absorbent main body provided with the absorbent core,

the absorbent article has an exterior member provided with a front waist portion joined to one side in a longitudinal direction of the absorbent main body and a rear waist portion joined to the other side in the longitudinal direction of the absorbent main body,

the absorbent article has a pair of side joining portions that join the left and right side portions of the front waistline portion and the rear waistline portion to each other in a state where the absorbent body is folded in two at a predetermined position in the longitudinal direction,

a hydrophilic nonwoven fabric is provided at least partially on the exterior member.

3. The absorbent article according to claim 1,

the absorbent article has an absorbent main body provided with the absorbent core,

the absorbent article includes an exterior member provided on a non-skin side of the absorbent body and integrally formed continuously from one side to the other side in a longitudinal direction of the absorbent body,

the absorbent article has a pair of side joining portions that join both side portions in the left-right direction on the one side in the longitudinal direction of the exterior member and both side portions in the left-right direction on the other side in the longitudinal direction of the exterior member to each other in a state where the absorbent body is folded in two at a predetermined position in the longitudinal direction,

a hydrophilic nonwoven fabric is provided at least partially on the exterior member.

4. The absorbent article according to claim 3,

when viewed in the thickness direction, the area of the portion where the absorbent core, the air-permeable film, and the hydrophilic nonwoven fabric overlap in the region below the lower end of the side joint is larger than the area of the portion where the absorbent core, the air-permeable film, and the hydrophilic nonwoven fabric overlap in the region above the lower end of the side joint.

5. The absorbent article according to claim 3 or 4,

the whole of the breathable film is overlapped with the hydrophilic nonwoven fabric when viewed from the thickness direction.

6. The absorbent article according to any one of claims 2 to 4,

the exterior member has an elastic member that expands and contracts in the left-right direction,

stress of a central portion of the elastic member in the left-right direction of the absorbent core is smaller than stress of both side portions of the elastic member in the left-right direction of the absorbent core.

7. The absorbent article according to claim 1,

the absorbent article has an absorbent main body provided with the absorbent core,

the absorbent article includes an exterior member provided on a non-skin side of the absorbent body and integrally formed continuously from one side to the other side in a longitudinal direction of the absorbent body,

a pair of hook and loop fasteners are provided at one end of the exterior member in the longitudinal direction,

a hydrophilic nonwoven fabric is provided at least partially on the exterior member.

8. The absorbent article according to any one of claims 2 to 4,

the exterior member has a hydrophobic nonwoven fabric having a hydrophilicity lower than that of the hydrophilic nonwoven fabric at a position closer to the skin than the hydrophilic nonwoven fabric.

9. The absorbent article according to any one of claims 2 to 4,

the hydrophilic nonwoven fabric is provided on the outermost non-skin side of the exterior member.

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

the absorbent article has a right-left direction,

the width of the hydrophilic nonwoven fabric in the left-right direction is larger than the width of the air-permeable film in the left-right direction,

the width of the air-permeable film in the left-right direction is greater than or equal to the width of the absorbent core in the left-right direction.

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

when viewed from the thickness direction, the absorbent core has a portion where the absorbent core overlaps the hydrophilic nonwoven fabric and a portion where the absorbent core does not overlap the hydrophilic nonwoven fabric.

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

the absorbent article has a slit portion penetrating the absorbent core in the thickness direction,

the absorbent article has a portion where the slit portion, the breathable film, and the hydrophilic nonwoven fabric overlap when viewed in the thickness direction.

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

the moisture permeability of the breathable film is 1000g/m²24h or more and 3500g/m²24h or less.

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