JP6207475B2 - Absorbent articles - Google Patents

Description

  This invention is absorbent articles, such as a sanitary napkin, a urine absorption pad, and a panty liner.

  Conventionally, an absorptive article provided with a liquid absorption layer which has extensibility is publicly known. For example, Patent Document 1 discloses a liquid-permeable surface layer located on the skin facing surface side, a back surface layer located on the non-skin facing surface side, and a liquid absorbing layer having extensibility interposed between both sheets. An absorbent article is disclosed.

JP 2009-153736 A

  According to the absorbent article disclosed in Patent Document 1, the surface layer and the back surface layer are composed of a stretchable sheet member and an elastic member fixed in a contracted state, and a plurality of layers formed in the liquid absorbing layer. The slits of the liquid-absorbing layer extend obliquely from both side edges of the liquid-absorbing layer and are spaced apart from each other in the length direction, or extend straight from the both-side edges of the liquid-absorbing layer in the width direction, and alternate between left and right in the vertical direction. Therefore, the slit is opened by extending it in the length direction, and the liquid absorbing layer is extended at least in the vertical direction. Therefore, the whole absorbent article including the liquid absorbing layer can be extended in the longitudinal direction so as to follow the wearer's body during the wearing operation and during wearing.

  However, when the slit has the former form, the central portion of the liquid absorption layer between the slits is not elongated in the vertical direction, and the entire liquid absorption layer is sufficiently extended so as to be in close contact with the wearer's body. I can't. On the other hand, when the slit has the latter form, the body fluid excreted in the central portion of the liquid absorption layer may move toward both side edges along the slit and easily leak to the outside. In addition, since the front and back layers are formed of an elastic sheet and an elastic member fixed in a contracted state, the entire absorbent article is curved even in a natural state, and is stretched in a flat state. I can't do it.

  An object of the present invention is to improve the conventional absorbent article, and it is excellent in fit by extending and shrinking along the wearer's body, and the body fluid excreted in the central part is difficult to leak, and the required absorption performance It is providing the absorbent article provided with the liquid absorption layer which has.

  In order to solve the above problems, the present invention is directed to a vertical axis and a horizontal axis, a skin facing surface and a non-skin facing surface on the opposite side, a surface layer located on the skin facing surface side, It is an absorptive article containing the back layer located in the non-skin opposing surface side, and the liquid absorption layer interposed between the front and back layers.

In the absorbent article according to the present invention, the front surface layer and the back surface layer are composed of one or a plurality of sheet members and have extensibility at least in the direction of the vertical axis. At least one of the constituting sheet members has elasticity in the direction of the vertical axis, and the liquid-absorbing layer has a given dimension in the direction of the vertical axis at the center in the direction of the horizontal axis. A plurality of central elongating means spaced apart, and a plurality of side elongating means located on both sides and arranged alternately with the central elongating means in the direction of the longitudinal axis , is formed from only the first slit Paragraph intersecting the longitudinal axis, the side extension means extends toward the longitudinal axis from each of opposite side edges of said liquid-absorbent layer, and the horizontal in the longitudinal axis near a pair of spaced apart in the direction of the axis to each other the Is formed from the slit only, the inner end of the previous SL second slits is positioned on the vertical axis side than the outer end of the first slit, wherein the liquid absorbing layer is, extensible in the direction of at least said longitudinal axis is there.

  The disposable absorbent article according to the present invention has a central extension means composed of a plurality of first slits arranged in the direction of the vertical axis in the central portion of the liquid absorption layer, and extends from both side edges of the liquid absorption layer toward the vertical axis, and The liquid absorbing layer can extend at least in the direction of the vertical axis by having side extension means in which a pair of second slits facing each other in the direction of the horizontal axis are arranged in the direction of the vertical axis. Therefore, in a state where the absorbent article is attached to clothes such as underwear, the absorbent article is stretched together with other sheet members, and the absorbent article can be deformed into a curved shape along the body shape of the wearer. Further, since the first slits and the second slits are alternately arranged in the direction of the vertical axis, the bodily fluid excreted between the first slits in the central part moves to both sides and is difficult to leak to the outside. Moreover, since a part of 1st slit and 2nd slit cross | intersect in the direction of a vertical axis | shaft, even if the opening by each slit is comparatively small, it can expand | extend to the direction of a vertical axis | shaft more. Furthermore, at least one of the sheets constituting the front and back layers has stretchability, and the stretchable sheet does not shrink excessively in the natural state, so the absorbent article is relatively flat. It becomes easy to become a shape.

The partially broken top view which looked at the sanitary napkin shown as an example of the absorbent article of this invention from the surface side. The top view which looked at the sanitary napkin from the back side. FIG. 3 is a schematic cross-sectional view taken along line III-III in FIG. 1. The top view of a liquid absorption layer. The top view in the state which extended the liquid absorption layer to the vertical direction. The figure which shows the wearing condition which showed the sanitary napkin with the virtual line, and showed only the liquid absorption layer with the continuous line. The top view similar to FIG. 5 which shows the example of a change of a liquid absorption layer. The top view in the state where the liquid absorption layer in modification example 1 was extended. The partially broken top view similar to FIG. FIG. 10 is a schematic sectional view taken along line XX in FIG. 9.

  1 to 3, a sanitary napkin 10 shown as an example of the absorbent article of the present invention has a longitudinal axis P that bisects the dimension in the width direction and a side that divides the dimension in the length dimension into two. And has an axis Q, and is curved at the skin facing surface side and the non-skin facing surface side opposite thereto, convex curved first and second end edges 10a and 10b, and a central portion where the horizontal axis Q is located. Both side edges 10c and 10d, a liquid-permeable surface sheet 11 located on the skin facing surface side, a stretchable and liquid-impermeable back sheet 12 located on the non-skin facing surface side, 12 includes a liquid-absorbing liquid-absorbing layer 13 located between 12 and a leak-proof sheet 14 covering the bottom surface of the liquid-absorbing layer 13. In order to improve the flexibility of the sanitary napkin 10, an intermediate sheet made of a relatively bulky fiber nonwoven fabric may be disposed between the top sheet 11 and the liquid absorbing layer 13.

  In the present invention, in the region where the liquid absorption layer 13 exists, the layer composed of one or more sheet members positioned on the skin facing surface side is positioned on the surface layer 8 and the non-skin facing surface side of the liquid absorbing structure 13. A layer composed of one or a plurality of sheet members is referred to as a back layer 9. Therefore, the liquid absorption layer 13 is disposed between the front surface layer 8 and the back surface layer 9. In the present embodiment, the surface layer 8 is composed of a surface sheet 11 and an intermediate sheet (not shown), and the back surface layer 9 is composed of a back surface sheet 12 and a leak-proof sheet 14. In the present embodiment, a pair of side sheets 20 described later is formed of a sheet member separate from the back sheet 12, but the side sheet 20 is not disposed, and the back sheet 12 is the entire sanitary napkin 10. It may be formed from a sheet material having a size, and the wing portion may be formed from the back sheet 12. In this specification, the elongation rate of 100% means that the length is 2 times the length of the natural state before the stretching force is applied, and the elongation rate of 50% is that the stretching force is applied. This means that the length is 1.5 times longer than the length of the natural state. Further, pulling the sanitary napkin 10 in the direction of the vertical axis P means that the sanitary napkin 10 is gripped by one end and the other end in the reverse direction so that they are separated from each other in the direction of the vertical axis P. It means that one end is fixed and the other end is pulled outward in the direction of the vertical axis P so as to be separated from the one end.

  The liquid absorption layer 13 has extending means that can be extended at least in the direction of the longitudinal axis P, which is disposed over the entire area. The extension means extends in the direction of the horizontal axis Q, and a central extension means 16 composed of a plurality of first slits 15 extending in the direction of the horizontal axis Q arranged side by side in the direction of the vertical axis P. Side extension means 18 composed of a plurality of second slits 17 arranged side by side in a state of being spaced apart by a given dimension in the direction of the longitudinal axis P on both sides. The first and second slits 15 and 17 of the liquid absorbing layer 13 in the present embodiment are those in which a part of the liquid absorbing layer 13 remains on the front surface side or the back surface side in addition to penetrating the liquid absorbing layer 13. In addition, a groove that allows the liquid absorbing layer 13 to extend at least in the direction of the longitudinal axis P is included.

  The top sheet 11 is joined to a surface of the leak-proof sheet 14 facing the back sheet 12 by bending both side portions (folded portions) 19 inward. The back sheet 12 extends further outward in the direction of the horizontal axis Q than the top sheet 11, and a pair of side sheets 20 are fixed on the front surface side. An end flap 22 located outside the liquid absorbing layer 13 in the direction of the vertical axis P is formed by a part of the top sheet 11, the back sheet 12 and the side sheet 20, and the liquid absorbing layer 13 is formed by the back sheet 12 and the side sheet 20. A side flap 24 having a pair of wing portions 23 that are located on the outer side in the direction of the horizontal axis Q and bend outward in the vicinity of the horizontal axis Q is formed. By disposing the leak-proof sheet 14 on the bottom surface of the liquid-absorbing layer 13, leakage of body fluid can be prevented.

  The front surface layer 8 and the back surface layer 9 are composed of one or a plurality of sheet members (the front surface layer 8 is a front surface sheet 11 and an intermediate sheet, and the back surface layer 9 is a back surface sheet 12 and a leak-proof sheet 14). It has extensibility in the direction of the axis P. That is, all the sheets constituting the front and back layers 8 and 9 have elastic or inelastic stretchability. As an inelastic and stretchable sheet, for example, spunbond fiber nonwoven fabric, various known fiber nonwoven fabrics such as SMS (spunbond / meltblown / spunbond) and fiber nonwoven fabric, and plastic film can be subjected to gear stretching and slit processing. By applying, what gave the predetermined extensibility to the direction of the vertical axis | shaft P can be used.

The sheet having elasticity and extensibility constituting the front and back surface layers 8 and 9 (i.e., stretchable sheet) As a mass 10 to 40 g / ^{m 2,} more preferably, the elastic fibers of the mass 15 to 30 g / ^{m 2} A stretchable fiber nonwoven fabric manufactured by various known production methods such as a spunbond nonwoven fabric, an air-through nonwoven fabric, and a needle punched nonwoven fabric composed of (elastic filament) can be used. Elastic fibers are made from thermoplastic elastomer, rubber, etc., and especially when thermoplastic elastomer is used as a raw material, melt spinning using an extruder is possible in the same way as ordinary thermoplastic resins. The fibers thus obtained are easy to heat-seal and are suitable as stretchable fiber nonwoven fabrics. Examples of the thermoplastic elastomer include SBS (styrene-butadiene-styrene), SIS (styrene-isoprene-styrene), SEBS (styrene-ethylene-butadiene-styrene), and SEPS (styrene-ethylene-propylene-styrene). And olefin elastomers, polyester elastomers, and polyurethane elastomers. These can be used individually by 1 type or in combination of 2 or more types. Further, core-sheath type or side-by-side type composite fibers made of these resins can also be used.

  Here, in the present invention, the “extensible sheet” means that the target sheet is stretched from the natural state in the direction of the vertical axis P with a force of 30 mN / 25 mm in the direction of the vertical axis P in the natural state. It is possible to elongate by 3% or more from the dimension, that is, it becomes possible to increase the length by 1.03 times or more from the length before the extension force is applied.

<Measurement of elongation ratio of stretchable sheet>
An Instron type universal tensile testing machine (manufactured by Shimadzu Corporation, Autograph AG-1) was used for measuring the elongation rate of the sheet having extensibility. As a specific measurement method, a sample having a size of 50 mm × 25 mm in the direction of the vertical axis P and the direction of the horizontal axis Q is cut out from a stretchable sheet, and both ends of the sample are gripped by chucks. When the length 30 mm in the direction of the vertical axis P is pulled at a speed of 100 mm / min, an extension force of 30 mN is applied in the direction of the vertical axis Q per 25 mm width in the horizontal axis Q direction. The elongation (%) was measured.

  Further, at least one of the sheet members constituting the front and back layers 8 and 9 has elasticity in the direction of the vertical axis P. In addition to the elastic stretchable nonwoven fabric described above, the sheet having stretchability is a spunbond nonwoven fabric composed only of elastic fibers, SMS (spunbond / meltblown / spunbond) or SM (spunbond / meltblown). A plurality of layers or the like can be used, and the stretchable nonwoven fabric can be formed from a stretchable composite sheet formed by joining the stretchable nonwoven fabric with a nonstretchable nonwoven fabric composed of nonstretchable fibers. The stretchable composite sheet can also be formed from a plurality of layers in which stretchable fiber nonwoven fabrics are arranged between two non-stretchable fiber nonwoven fabrics. The non-stretchable fiber nonwoven fabric is formed from various known fiber nonwoven fabrics such as an air-through fiber nonwoven fabric and a heat roll fiber nonwoven fabric in addition to the spunbond fiber nonwoven fabric. Examples of the constituent fibers of the nonwoven fabric used as the inelastic sheet include fibers made of polyethylene (PE), polypropylene (PP), polyester (PET), and the like.

  In the case of using a stretchable composite sheet of a stretchable fiber nonwoven fabric and a non-stretchable fiber nonwoven fabric as each of the sheets 11, 12, and 14, a stretchable stretched non-stretchable fiber nonwoven fabric at a predetermined magnification is used. Joining to the nonwoven fabric through a known joining means such as embossing or hot melt adhesive, or joining the two nonwoven fabrics and then cutting at least the non-stretchable nonwoven fabric into the entire composite sheet Elasticity may be imparted. Such partial cutting does not extend continuously in the entire width direction of the stretchable composite sheet, but is discretely arranged in the form of dots or slits, and mainly the non-stretchable fiber nonwoven fabric is cut and stretched. The non-woven fiber nonwoven fabric is preferably not cut so that its stretchability does not deteriorate.

  Here, the sheet having stretchability in the present invention is stretched to 60% or less, preferably 40% or less from the dimension of the vertical axis P in the natural state (stretched 1.4 to 1.6 times). In the state), it is fixed to another sheet member. Thus, the stretchable sheet is fixed at a relatively low elongation rate, and the liquid absorbing layer 13 of the sanitary napkin 10 has the required rigidity, so that the stretchable sheet shrinks. Without maintaining the stretched state. Accordingly, the sanitary napkin 10 has a flat shape in a natural state, and is further extended from the extended state when a pulling force is applied in the direction of the longitudinal axis P to the sanitary napkin. A flat form can be maintained. Therefore, even when it is stretched together with it being fastened to the clothes, it can exhibit a curved shape that conforms to the shape of the body.

  It was confirmed by the following method that the stretchable sheet was fixed at a predetermined elongation rate. First, in the case where the core wrap sheet 29 or the side sheet 20 to which the back sheet (plastic film) 12 is bonded is formed from an inelastic and extensible sheet, and the back sheet 12 is formed from a stretchable sheet. A part of the part where both sheets were joined via a hot melt adhesive was cut out from the sanitary napkin 10 to prepare a sample. Next, a cold spray was sprayed on the bonding interface of the sample to separate the sheet piece of the inelastic and stretchable sheet and the sheet piece of the stretchable sheet into a natural state. Measure the length dimension of both sheet pieces in the natural state and calculate the length dimension (mm) of the inelastic and extensible sheet piece ÷ the length (mm) of the sheet piece of the stretchable sheet. The calculated value was 1.6 or less. Therefore, it was confirmed that the back sheet 12 which is a stretchable sheet was fixed in a state where the elongation rate was 60% or less.

  The top sheet 11 has liquid permeability so as to permeate body fluid and be absorbed and retained in the liquid absorption layer 13, and is obtained by hydrophilizing the above-described constituent fibers or fiber nonwoven fabric, or hydrophilic as constituent fibers. A fiber nonwoven fabric using a conductive fiber can be used. Moreover, you may have required liquid permeability by using a porous fiber nonwoven fabric, without performing a hydrophilic process. The leak-proof sheet 14 has hydrophobicity and is formed from an (elastic) thermoplastic film mainly composed of a thermoplastic polyurethane polymer or the like. The leak-proof sheet 14 can also be formed from a composite sheet of such a thermoplastic film and a stretchable fiber nonwoven fabric.

  The liquid-absorbing layer 13 is a panel shape shaped to a predetermined shape and size, and has a liquid-absorbing core 28 having a semi-rigidity and elasticity that is higher than that of a sheet member, and an option, A liquid-permeable and extensible core wrap sheet 29 is provided to enclose the liquid-absorbent core 28 in order to improve shape retention and liquid diffusibility. As with other stretchable sheets, the core wrap sheet 29 includes a known fiber nonwoven fabric that has been subjected to gear stretching or slit processing, an elastic fiber nonwoven fabric, or an elastic fiber nonwoven fabric that is subjected to gear stretching. The elastic elastic sheet which was made is used suitably. The liquid absorbent core 28 is formed from a mixture of airlaid fiber nonwoven fabric, fluffed wood pulp, and superabsorbent polymer particles (SAP). For example, chemical pulp, cellulose fiber, rayon, and acetate can be used as the fluff wood pulp. As the airlaid nonwoven fabric, for example, a material obtained by thermally fusing pulp and synthetic fiber or bonding them with a binder can be used. The superabsorbent polymer particles have a three-dimensional network structure in which a water-soluble polymer is appropriately cross-linked, and absorb water 30 to 60 times its own weight but are essentially water-insoluble. , Acrylic acid-based, and amino acid-based particulate or fibrous polymers can be used.

  As the liquid absorption layer 13 according to the present embodiment, it is preferable to use a layer formed by laminating an airlaid fiber nonwoven fabric in a single layer or a plurality of layers, which does not contain superabsorbent polymer particles. By not including the superabsorbent polymer particles, it is easy to form the first and second slits 15 and 17 in the manufacturing process, and the fine particulate superabsorbent polymer particles leak out from the slits 15 and 17. Because there is no. In addition, since the first and second slits 15 and 17 are formed, it is difficult for the body fluid to diffuse in the direction of the vertical axis P. The superabsorbent polymer particles are compared with absorbent materials such as fluff wood pulp. Since the absorption rate is slow, it is possible to prevent further reduction in diffusion and absorption rate in the direction of the vertical axis P due to the absence of superabsorbent polymer particles.

  Referring to FIG. 2, a central portion formed of a pressure-sensitive adhesive for attaching the sanitary napkin 10 to clothes such as underwear on the back side of the sanitary napkin 10, that is, the outer surface of the back sheet 12. , A plurality of first fastening portions 31 that extend in a line shape in the direction of the horizontal axis Q and are arranged in the direction of the vertical axis P with a predetermined distance are arranged. In addition, a second fastening part 32 made of a pressure sensitive adhesive is also arranged on the outer surface of the wing part 23. The first and second fastening portions 31 and 32 are covered with a separator 33 made of a plastic film or a fiber nonwoven fabric. It is preferable that the 1st and 2nd fastening parts 31 and 32 have the fastening intensity | strength with respect to a wearer's clothing sufficient in a practical level, Specifically, it is about 2.0-4.0N fastening. Has strength. The first and second fastening portions 31 and 32 do not overlap each other in the plan view of the first and second slits 15 and 17 and the diaper 10, and at least the existence region of the liquid absorbing layer 13 is in the direction of the vertical axis P. It is preferable that the region on the first end edge 10a side and the region on the second end edge 10b side do not overlap each other in plan view. As described above, since the first and second fastening portions 31 and 32 do not overlap with the first and second slits 15 and 17 in plan view, the openings of the slits 15 and 17 at the time of extension are not suppressed. The liquid absorbing layer 13 can exhibit the required extensibility. When the first and second fastening portions 31 and 32 have such an arrangement mode, the required extensibility can be ensured on both end sides of the sanitary napkin 10, and compared with the case where the extensibility is suppressed. And a feeling of wear becomes good.

  Although not shown, at the outer peripheral edge of the sanitary napkin 10 defined by the first and second end edges 10a, 10b and both side edges 10c, 10d, each sheet member is a known joining means, for example, a heat A seal portion (round seal) joined by various heat welding means such as embossing and sonic processing is formed. In addition, the sheet members that overlap each other except for the outer peripheral edge joined by the seal portion can use a hot melt adhesive known in this type of field, but the stretchability of the sanitary napkin 10 as a whole can be increased. In order not to inhibit, it is preferable to use a hot melt adhesive made of a known rubber adhesive or the like and a mixture thereof.

  As a method of forming the first and second slits 15 and 17 in the liquid absorbing layer 13, a known cutting means can be adopted. However, when the liquid absorbing layer 13 includes superabsorbent polymer particles, thermoplasticity is adopted. When a heat-sealing material such as fiber is mixed and only the liquid-absorbent core 28 is encased in the core wrap sheet 29 or is partially cut by the cutting means, heat is applied simultaneously with or before and after the cutting. A fusible material (when the core wrap sheet 29 is formed of thermoplastic fibers, the core wrap sheet 29 is also fused at the same time) is fused, and the heat fusible material is highly absorbent from the cut surface. It is possible to prevent the polymer particles from leaking out.

  4 and 5, the liquid absorption layer 13 has front and rear end edges 13a and 13b facing each other in the direction of the vertical axis P, and both side edges 13c and 13d facing each other in the direction of the horizontal axis Q. The central extending means 16 is composed of a plurality of first slits 15 that intersect with the vertical axis P in the central portion of the liquid absorption layer 13 and are spaced apart by a given dimension in the direction of the vertical axis P. On the other hand, the side extending means 18 extends between the first slits 15 from both side edges 10c and 10d toward the vertical axis P, and is separated from each other in the direction of the horizontal axis Q in the vicinity of the vertical axis P. It is composed of a pair of second slits 17. A part of the first slit 15 and the second slit 17 intersect each other in the direction of the vertical axis P. Here, “crossing each other” means that the inner ends of the second slits 17 extending from the side edges 13c and 13d toward the vertical axis P are located closer to the vertical axis P than the outer ends of the first slits 15, Are partially located opposite to each other in the direction of the vertical axis P. The liquid absorbing layer 13 includes the central extending means 16 and the side extending means 18 so that when the entire sanitary napkin 10 is extended in the direction of the vertical axis P together with other sheet members, the liquid absorbing layer 13 absorbs liquid by the first slit 15. A plurality of circular openings are formed in the central portion of the layer 13, and the portion between the openings is also extended in the direction of the vertical axis P by the second slits 17 extending inwardly from the side edges 13c and 13d. Is expanded in the direction of the vertical axis P.

  Since at least one sheet member of the sheet members constituting the front and back layers 8 and 9 has stretchability, the sanitary napkin 10 has a performance of contracting after being stretched. Specifically, for example, if at least one sheet member of the back sheet 12, the leak-proof sheet 14, and the side sheet 20 constituting the back layer 9 is stretchable, the sanitary napkin 10 as a whole is vertical. When extended in the direction of the axis P, it can expand and contract. In order to achieve the technical effect of the present embodiment, when the sanitary napkin 10 itself is pulled from the natural state with a force of about 700 mN / 25 mm in the direction of the vertical axis, at least 3% in the direction of the vertical axis. It is preferable that the length can be extended, that is, the length is 1.03 times or more from the length before the extension force is applied. In such a case, when the sanitary napkin 10 is stretched in the direction of the vertical axis P, the liquid absorbing layer 13 is stretched together with the front and back layers 8 and 9 by the stretching means 16 and 18, and the sanitary napkin 10 is Along with the clothing, it can be shaped along the body shape. Moreover, since the sheet | seat which has a stretching property shrink | contracts according to the predetermined | prescribed elongation rate to which the sanitary napkin 10 was fixed, it can adapt also to the movement of the body during wear.

<Measurement method of elongation rate of sanitary napkin>
Both ends of the sanitary napkin 10 are gripped with a width of 10 to 20 mm by a chuck of a tensile tester (for example, an Instron type tensile tester) and pulled at a speed of 100 mm / min for a width of 25 mm. The elongation rate (%) was measured when an extension force of 700 mN was applied in the direction of the vertical axis P without damaging the use napkin. Although not shown, when the sanitary napkin 10 includes a three-dimensional cuff having an upright property, the measurement is performed with the three-dimensional cuff removed.

  The elongation rate in the direction of the vertical axis P of the liquid absorption layer 13 depends on the shape, size, separation dimension, and the like of the first and second slits 15, 17. In order to have an expansion ratio of 150 to 200%, when the dimension W1 in the horizontal axis Q direction of the liquid absorption layer 13 is about 50 to 120 mm and the dimension L1 in the direction of the vertical axis P is about 150 to 470 mm, The length dimension (dimension in the direction of the horizontal axis Q) W2 of the first and second slits 15 and 17 is preferably about 30 to 70 mm, more preferably about 40 to 60 mm, and the first slits 15 adjacent in the direction of the vertical axis P. The distance R1 between the second slit 17 and the second slit 17 in the direction of the vertical axis P is preferably about 5 to 30 mm, more preferably about 8 to 15 mm. Dimension R2 is Preferably about 5 to 30 mm, more preferably about 10 to 20 mm.

  When the length dimension W2 of the 1st and 2nd slits 15 and 17 is about 30 mm or less, the liquid absorption layer 13 is not fully extended in the direction of the vertical axis P, and the extensibility of the sanitary napkin 10 as a whole is reduced. There is a risk. On the other hand, when the dimension W2 is about 70 mm or more, the tensile strength of the liquid-absorbing layer 13 is lowered, and the shape may collapse during the wearing operation or during wearing. When the separation dimensions R1 and R2 are about 5 mm or less, the extensibility of the liquid absorbing layer 13 is improved, while the separation dimension R1 between the first slit 15 and the second slit 17 and the distance between the second slits 17 are increased. The separation dimension R2 is reduced, the tensile strength of the liquid absorbing layer 13 is decreased, and there is a possibility that a part of the liquid absorption layer 13 is broken during wearing or wearing operation. On the other hand, when the separation dimensions R1 and R2 are each about 30 mm or more, the liquid absorption layer 13 has the required tensile strength, but the extensibility is lowered, and the sanitary napkin 10 as a whole is fully stretched when attached to the clothes. You may not be able to do it.

  Referring to FIG. 6, when the sanitary napkin 10 is worn, the sanitary napkin 10 is attached to the inner surface of the garment, and each sheet member constituting the sanitary napkin 10 and the liquid absorption layer 13 together with the garment are worn by the wearer's body. 39, the adhesion to the body 39 of the clothes and the wearer is improved, and it is easy to adapt to the movement of the wearer's body 39, and is excellent in leakage prevention and wearability. The first and second slits 15 and 17 constituting the central extending means 16 and the side extending means 18 are provided at regular positions in the entire liquid absorbing layer 13, so that the first and first slits are extended when they are extended. Since the openings formed by the two slits 15 and 17 are formed in a regular shape and size, the liquid absorption layer 13 is expanded from the case where the slits are formed in an irregular size and position. It easily shrinks and returns to its original state, and it has excellent recoverability. Further, since the second slit 17 extends inward from the side edges 10c and 10d, the liquid absorbing layer 13 is compared with a case where the second slit 17 extends inward from a position inside the side edges 10c and 10d. The whole is easily extended in the direction of the vertical axis P.

  Further, for example, when the extending means of the liquid absorption layer 15 is formed of only slits extending inward from the side edges 10c and 10d, the body fluid excreted in the liquid absorption layer 15 is laterally moved along the slits. In the present embodiment, there is a possibility that the liquid may move in the direction of the axis Q and leak to the outside of the liquid absorbing layer 15. Since the second slit 17 extending inwardly from both side edges 10c, 10d is located between the one slit 15, the body fluid 40 excreted between the first slits 15 in the central portion is located outside in the direction of the horizontal axis Q from the central portion. It will be difficult to leak outside. In addition, when a part of the first and second slits 15 and 17 intersects in the direction of the vertical axis P, it is easy to extend further in the direction of the vertical axis P, and one opening is relatively small. Can also exhibit the required elongation. That is, according to the arrangement pattern of the first and second slits 15 and 17 of the present embodiment, both required extensibility and body fluid absorption retention can be achieved. Further, in at least one of the front and back layers 8 and 9, at least one of the constituting sheet members has elasticity, so that the sanitary napkin 10 as a whole can be slightly contracted, and the body movement during wearing can be reduced. Can adapt.

Moreover, as another Example, all the sheet members which comprise the front and back surface layers 8 and 9, ie, the surface sheet 11, the back surface sheet 12, the leak-proof sheet 14, and the side sheet 20, for example, an elastic stretch fiber nonwoven fabric etc. It can also form from the sheet | seat which has the elasticity of these. In such a case, for example, the density of the liquid absorbing layer 13 is preferably about 0.06 to 0.1 g / cm ³ , and the liquid absorbing layer 13 preferably has an elongation rate of about 100 to 200%. Usually, clothing such as cloth underwear is at least about 50% in the longitudinal direction so as to exhibit a curved shape along the perineum of the wearer at the crotch portion in order to exhibit fitability to the wearer's body. It is designed and manufactured to stretch (from the dimension before the stretching force is applied). In order to attach the sanitary napkin 10 to the clothes and elongate it by about 50%, each sheet member constituting the sanitary napkin 10 and the liquid-absorbing layer 13 are sealed at the outer peripheral edge, hot melt adhesive, etc. Of the members constituting the sanitary napkin 10 with respect to the expansion ratio of about 50% of the clothes, considering that the elongation rate of the sheet material and the material of the liquid-absorbing layer 13 itself is reduced. It can be said that the shape of the liquid-absorbing layer 13 that is most difficult to maintain the shape after expansion / contraction can be easily maintained even when the expansion / contraction is repeated by allowing the liquid-absorbing layer 13 to extend to 100% or more.

<Measurement method of elongation rate of liquid absorption layer>
As a method for measuring the elongation rate of the liquid absorbing layer 13, first, a cold spray is sprayed on the bonding interface of the liquid absorbing layer 13, and the liquid absorbing layer 13 is taken out from the sanitary napkin 10 to obtain a sample. One end of the sample is clamped with a tensile tester (for example, an Instron type tensile tester) on one chuck, the other end is clamped on the other chuck, and the liquid absorption layer 13 is absorbed at a pulling speed of 50 mm / min. Pull until the core 28 is visually ruptured. The length dimension in the direction of the vertical axis P of the liquid absorbent layer 13 at the time of breaking of the liquid absorbent core 28 ÷ the length dimension in the direction of the vertical axis P when taken out from the sanitary napkin 10 (initial), for example, If the calculated value is 2.5, the expansion rate is 150%.

  Thus, when the surface sheet 11 is formed from the stretchable fiber nonwoven fabric which has liquid permeability, the touch is favorable and all the sheet members which touch a wearer's skin, ie, the surface layer 8, are attached. The surface sheet 11, the back sheet 12, and the side sheet 20 that are formed are all formed of a stretchable nonwoven fabric, so that the sanitary napkin as a whole has a touch and flexibility like underwear, and the wearing feeling is improved. . Moreover, since the side flap 24 is formed by the front and back sheets 11 and 12 having elasticity and the side sheet 20 having elasticity, the side flap 24 is formed only from the front and back sheets 11 and 12. In comparison, the strength of the side flaps 24 is improved and the stretchability is improved. When fixed, it is stably fixed.

<Modification 1>
Referring to FIGS. 7 and 8, in one modified example of the liquid absorbing layer 13, the first and second slits 15 and 17 are wavy, and the liquid absorbing layer 13 extends in the direction of the vertical axis P together with the clothes. In this state, the opening formed by the first and second slits 15 and 17 has a wavy shape. If the first and second slits are straight, they will bend and fit to the body, so the part deformed from straight to bend will be slightly deformed or hardened. When there is a possibility of giving the person a sense of discomfort, as in the present modification example, when it is wavy and so to speak, it is curved along the shape of the slit, so that it can be suppressed. .

<Modification 2>
Referring to FIGS. 9 and 10, in this modified example, between the top sheet 11 and the side sheet 20, between the first and second end edges 10 a and 10 b, from the outer edge of the bent portion 19. A pair of elastic auxiliary sheets 26 extending to the inner edge of the portion 23 are arranged. The elastic auxiliary sheet 26 is positioned outside both sides of the liquid absorbing layer 13 and imparts stretchability to the arrangement region thereof, so that the semi-rigid liquid absorbing layer 13 having a rigidity higher than that of the sheet member is applied to clothing such as underwear. At the same time, it helps to be extended in a curved shape. Thus, the sanitary napkin 10 is more worn during wear by the elastic auxiliary sheet 26 extending and contracting together with the elastic sheet that is one of the sheet members constituting the front and back layers 8 and 9. It can be said that it becomes easy to adapt to the movement of the.

  In addition to the materials described in the present specification, the components constituting the sanitary napkin 10 are not limited to the materials described in the present specification. The material can be used without limitation. Further, the terms “first” and “second” used in the present specification and claims are merely used to distinguish similar elements, positions, and the like. Moreover, in order to improve the diffusibility of a bodily fluid from the surface side to the back surface side of the sanitary napkin 10, the compression groove | channel of a predetermined pattern may be formed.

  The disclosure relating to the present invention described above can be summarized at least as follows.

Vertical axis and horizontal axis, skin facing surface and non-skin facing surface on the opposite side, surface layer located on the skin facing surface side, back layer located on the non-skin facing surface side, and front and back layers In the absorbent article including the liquid-absorbing layer interposed in the surface layer, the front surface layer and the back surface layer are composed of one or a plurality of sheet members and have extensibility in at least the direction of the vertical axis. In addition, at least one of the sheet members constituting the front and back surface layers has elasticity in the direction of the vertical axis, and the liquid absorption layer is formed in the central portion in the direction of the horizontal axis. A plurality of central extension means disposed at a given distance apart in the direction of, and a plurality of side extension means located on both sides and arranged alternately with the central extension means in the direction of the longitudinal axis , It said central elongated section, the first slit Paragraph intersecting the longitudinal axis Is formed from the side extension means extending from said respective side edges of the liquid-absorbent layer toward said longitudinal axis, and only a pair of second slits spaced apart from each other in the longitudinal axis near the direction of the transverse axis is formed from the outer end of the inner end of the previous SL second slit first slit located in the vertical-axis side, the liquid absorbing layer is extendable in the direction of at least said longitudinal axis.

The present invention disclosed in the above paragraph can include at least the following embodiments.
(1) when pulled by the force of Oite 700 mN / 25 mm from the natural state in the direction of the longitudinal axis, it is stretchable at least 3% or more in the direction of the longitudinal axis.
(2) The surface layer has a liquid-permeable surface sheet, the back surface layer has a liquid-impermeable back sheet, and at least one of the front and back sheets is made of a stretchable fiber nonwoven fabric. It is formed.
(3) The separation dimension of the first slit and the second slit in the direction of the vertical axis is 5.0 to 30.0 mm, and the separation dimension of the pair of second slits facing each other in the direction of the horizontal axis is 5.0 is a ~30.0mm.
(4) The back surface layer has a liquid-impervious and stretchable leak-proof sheet disposed on the bottom surface of the liquid absorbing layer.
(5) A side sheet having elasticity that extends outward from the both side edges of the liquid absorption layer in the direction of the horizontal axis is disposed.
(6) the topsheet on the outside of said opposite side edges of said liquid-absorbent layer, the backsheet and the side flaps are formed from the side sheet, a pair of resilient auxiliary sheet extending in the direction of the longitudinal axis is arranged .

10 Sanitary napkins (absorbent articles)
8 Surface layer 9 Back surface layer 11 Surface sheet 12 Back surface sheet 13 Absorbent layers 13c, 13d Side edges 14 of the absorbent layer Leak-proof sheet 15 First slit 16 Central extension means 17 Second slit 18 Side extension means 19 Both sides of the surface sheet Part (folded part)
20 Side seat 24 Side flap 26 Elastic auxiliary seat P Vertical axis Q Horizontal axis R1 Separation dimension R2 in the direction of the vertical axis of the first slit and the second slit R2 Separation dimension of the second slits facing each other in the direction of the horizontal axis

Claims (7)

Vertical axis and horizontal axis, skin facing surface and non-skin facing surface on the opposite side, surface layer located on the skin facing surface side, back layer located on the non-skin facing surface side, and front and back layers In an absorbent article including a liquid absorbing layer interposed in,
The front surface layer and the back surface layer are composed of one or a plurality of sheet members, and have at least extensibility in the direction of the vertical axis,
At least one of the sheet members constituting the front and back layers has elasticity in the direction of the vertical axis,
The liquid-absorbing layer is located at both sides of a plurality of central extension means arranged at a given distance in the vertical axis direction at the central portion in the horizontal axis direction, and in the vertical axis direction. A plurality of side extension means arranged alternately with the central extension means ,
It said central elongated section is formed from only the first slit Paragraph intersecting the longitudinal axis,
The side extension means is formed of only a pair of second slits extending from each of both side edges of the liquid absorption layer toward the vertical axis and spaced apart from each other in the horizontal axis direction in the vicinity of the vertical axis. And
Absorbable inner end of the previous SL second slits is positioned on the vertical axis side than the outer end of the first slit, wherein the liquid absorbing layer, characterized in that it is extensible in the direction of at least said longitudinal axis Goods.   The absorbent article according to claim 1, wherein the absorbent article can be stretched by at least 3% in the direction of the vertical axis when pulled with a force of 700 mN / 25 mm in the direction of the vertical axis from a natural state.   The surface layer has a liquid-permeable surface sheet, the back surface layer has a liquid-impermeable back sheet, and at least one of the front and back surfaces is formed from a stretchable fiber nonwoven fabric. The absorbent article according to claim 1 or 2.   The distance between the first slit and the second slit in the direction of the vertical axis is 5.0 to 30.0 mm, and the distance between the pair of second slits facing each other in the direction of the horizontal axis is 5.0. The absorptive article according to any one of claims 1 to 3 which is-30.0 mm.   The absorptive article according to any one of claims 1 to 4 in which said back layer has a liquid-impervious and elastic leakproof sheet arranged at the bottom of said liquid absorption layer.   The absorbent article in any one of Claims 1-5 by which the side sheet | seat which has the elasticity extended from the said both-sides edge of the said liquid absorption layer to the outer side of the direction of the said horizontal axis is arrange | positioned. The topsheet on the outside of said opposite side edges of said liquid-absorbent layer, the backsheet and the side flaps are formed from the side sheet, according to claim 3 in which a pair of resilient auxiliary sheet extending in the direction of the longitudinal axis is arranged Absorbent article as described in 1.