JP4204518B2 - Absorbent article surface sheet - Google Patents

Description

  The present invention relates to a surface sheet used for absorbent articles such as sanitary napkins, panty liners, cage sheets, incontinence pads, disposable diapers and the like. Moreover, this invention relates to the absorbent article provided with this surface sheet.

  2. Description of the Related Art As a surface sheet of an absorbent article, there is known a sheet in which two sheet materials are overlapped to provide an opening penetrating them and a convex portion is formed between the openings. For example, the present applicant has previously proposed a surface sheet of an absorbent article that is made of at least two layers of nonwoven fabric, has a large number of apertures, and each nonwoven fabric is bonded to each other at the periphery of the apertures (Patent Document 1). reference). In this surface sheet, a large number of flange portions and groove portions are alternately arranged so as not to have a flat surface portion, and the openings are arranged at intervals in the groove portions. According to this surface sheet, a dry feeling and a soft feeling are improved, and the concealability of the absorbed liquid is improved.

  Further, the present applicant has proposed a two-layer surface sheet having two layers and having a large number of convex portions and concave portions (see Patent Document 2). This surface sheet has a skin-facing surface made of non-woven fabric, and an opening is formed at the top of the convex portion or in the vicinity thereof, or at the bottom of the concave portion. A gap is formed between the two layers. This surface sheet is hard to remain liquid and does not feel sticky.

  Furthermore, a polyethylene film is doubled, a sealing part is provided in the middle to form a convex part, air or foamed elastic body is sealed in the convex part, and a through hole is formed at an adjacent position between the convex parts. A surface sheet of a functional article has also been proposed (see Patent Document 3). According to this surface sheet, the pressure applied to the absorber is reduced, so that the liquid is prevented from returning.

Japanese Patent Laid-Open No. 10-80445 JP 2002-238947 A Japanese Utility Model Publication No. 2-17126

  An object of the present invention is to provide a surface sheet of an absorbent article that has a cushioning feeling and a soft feeling that are improved compared to the above-described conventional surface sheet, and that liquid does not easily reverse.

In the surface sheet of an absorbent article comprising a laminated nonwoven fabric having an upper layer nonwoven fabric disposed on the skin side and a lower layer nonwoven fabric disposed on the absorber side,
In the laminated nonwoven fabric, a large number of liquid passage holes penetrating the laminated nonwoven fabric are formed, and the upper layer nonwoven fabric and the lower layer nonwoven fabric are joined to each other around the liquid passage hole,
The upper layer nonwoven fabric and the lower layer nonwoven fabric are both arched toward the skin side between the liquid passage holes, and a space is formed between the lower layer nonwoven fabric and the upper layer nonwoven fabric and the lower layer nonwoven fabric, respectively. A large number of raised portions that are raised toward the
The above-mentioned object is achieved by providing the surface sheet of the absorbent article in which the arched portion of the upper nonwoven fabric is a small convex portion smaller than the arched portion of the lower nonwoven fabric.

Moreover, the present invention provides an absorbent article in which a surface sheet is disposed on the skin side of the absorber,
The central region in the width direction of the top sheet is composed of the top sheet,
In each side region with respect to the central region in the surface sheet, the second bulge portion having a height lower than that of the bulge portion formed in the central region is higher than the density of the bulge portions formed in the central region. An absorbent article formed of is provided.

  The surface sheet of the present invention has an upper layer nonwoven fabric and a lower layer nonwoven fabric each formed in an arch shape, and a first space formed between them and a second space formed under the lower layer nonwoven fabric, The soft feeling is very high. This cushion feeling and soft feeling become more prominent due to the upper nonwoven fabric having small convex portions. Further, due to the presence of each of the spaces, the surface sheet is unlikely to return to the liquid. Furthermore, since the arch shape of the upper layer nonwoven fabric is smaller than the arch shape of the lower layer nonwoven fabric, the contact area between the surface sheet and the skin is reduced, and the feeling of slipping and slipping is excellent.

  The present invention will be described below based on preferred embodiments with reference to the drawings. FIG. 1 is a schematic view showing a perspective view of a top sheet of an absorbent article of the present invention, and FIG. 2 is a schematic view taken along line II-II in FIG. The surface sheet 1 of this embodiment is used as a surface sheet of a sanitary napkin that is an example of an absorbent article. The topsheet 1 is composed of a laminated nonwoven fabric having an upper layer nonwoven fabric 2 disposed on the wearer's skin side and a lower layer nonwoven fabric 3 disposed on the absorbent side of the napkin when the topsheet 1 is incorporated into the napkin. . A number of liquid passage holes 4 penetrating both the upper layer nonwoven fabric 2 and the lower layer nonwoven fabric 3 are formed in the top sheet 1. The liquid passage hole 4 is formed to be surrounded by a laminated nonwoven fabric extending from the skin side (upper surface side) of the topsheet 1 toward the absorber side (lower surface side). The opening end 4a of the liquid passage hole 4 protrudes in the direction of the absorber (not shown). The inner wall of the liquid passage hole 4 is composed of a continuous surface from the skin side (upper surface side) surface of the topsheet 1.

  The upper layer nonwoven fabric 2 and the lower layer nonwoven fabric 3 are joined at least around the liquid passage hole 4, that is, at the open end 4a of the liquid passage hole 4 and the vicinity thereof. In the portion other than the periphery of the liquid passage hole 4, the upper layer nonwoven fabric 2 and the lower layer nonwoven fabric 3 may not be substantially joined or may be joined. The term “bonded” means that the fibers constituting the upper and lower layer nonwoven fabrics 2 and 3 are mechanically entangled, thermally softened and melted, or bonded with a binder or the like. In addition, the fact that the upper layer nonwoven fabric 2 and the lower layer nonwoven fabric 3 are not completely separated from each other means that the upper layer nonwoven fabric 2 and the lower layer nonwoven fabric 3 are in contact with each other. It also includes a state in which it is easily separated by a force applied to the top sheet 1 inside.

  Between the liquid passage holes 4, 4, the upper layer nonwoven fabric 2 and the lower layer nonwoven fabric 3 are both raised in an arch shape toward the skin side. A first space 5 a is formed between the upper layer nonwoven fabric 2 and the lower layer nonwoven fabric 3, and a second space 5 b is further formed below the lower layer nonwoven fabric 3. Furthermore, when viewed from the top sheet 1 as a whole, a large number of raised portions 6 bulging toward the skin side are formed on the top sheet 1. The raised portions 6 are each composed of an upper layer nonwoven fabric 2 and a lower layer nonwoven fabric 3 that are raised in an arch shape toward the skin side.

  As shown in FIG. 2, the arched portion of the upper nonwoven fabric is a small convex portion 7 that is smaller than the arched portion of the lower nonwoven fabric. The small convex portions 7 are discretely arranged over the entire area of the upper nonwoven fabric 2 and have independent island shapes. A trough 7b (described as 7b in FIG. 2) existing between the adjacent small convex portions 7 and 7 is in contact with the upper surface side of the lower layer nonwoven fabric 3, or is separated therefrom. In particular, when the valley portion 7 b is in contact with the upper surface side of the lower layer nonwoven fabric 3, there is an advantage that the liquid transfer property from the upper layer nonwoven fabric 2 to the lower layer nonwoven fabric 3 is improved. Moreover, there exists an advantage that the shape of the small convex part 7 is supported by the shape which protruded in the arch shape of the lower layer nonwoven fabric 3, and becomes difficult to deform | transform.

  As described above, the raised portion 6 has a two-layer structure of the upper nonwoven fabric 2 and the lower nonwoven fabric 3, and the first space 5a is formed between the nonwoven fabrics. In this case, the small convex portion 7 formed on the upper nonwoven fabric 2 is deformed first, and then the arch shape of the lower nonwoven fabric 3 is deformed. Therefore, the surface sheet 1 of the present embodiment has excellent cushion feeling and soft feeling, and the liquid once absorbed by the absorber (not shown) is difficult to return to the surface sheet 1 side. That is, so-called wetback is unlikely to occur.

  In particular, since the top sheet 7 comes into contact with the skin at the tops of a large number of small convex portions 7, the above-mentioned cushion feeling and soft feeling become more remarkable due to the body pressure dispersion effect. Furthermore, since the arch shape (small convex part 7) of the upper layer nonwoven fabric 2 is smaller than the arch shape of the lower layer nonwoven fabric 3, the contact area between the surface sheet 1 and the skin is reduced, and the feeling of slipping and slipping is excellent. Become.

  Moreover, when the rigidity of the lower layer nonwoven fabric 3 is higher than that of the upper layer nonwoven fabric 2, the arch shape of the lower layer nonwoven fabric 3 prevents deformation of the raised portion 6 even when the body pressure of the wearer is applied to the top sheet 1. Since it acts as a support part, when it sees as the whole protruding part 6, the protruding shape is maintained stably. As a result, the surface sheet 1 in the present embodiment can reduce the contact area between the skin of the wearer and the skin side surface of the surface sheet 1, prevent the occurrence of discomfort, and improve the air permeability. Can keep. In addition, from a viewpoint of keeping an arch shape stably, it is preferable that the upper-layer nonwoven fabric 2 is also comprised from the highly rigid nonwoven fabric. However, when the rigidity of the upper layer nonwoven fabric 2 is increased, the texture of the nonwoven fabric tends to be lowered. Therefore, in the topsheet 1 of the present embodiment, the lower layer nonwoven fabric 3 is made more rigid than the upper layer nonwoven fabric 2 to prevent deformation of the arch shape by the lower layer nonwoven fabric 3 and a good texture is expressed by the upper layer nonwoven fabric 2. Yes.

  In order to increase the rigidity of the lower layer nonwoven fabric 3, for example, it is effective to increase the basis weight, but in that case, the texture of the surface sheet 1 as a whole tends to be lowered, and it is advantageous from the viewpoint of manufacturing costs. I can't say that. Therefore, in the present embodiment, it is preferable to use an embossed nonwoven fabric as the lower layer nonwoven fabric 3. On the other hand, with respect to the upper layer nonwoven fabric 2, it is preferable to use a non-embossed nonwoven fabric from the viewpoint of improving the texture. The term “not embossed” as used herein means that the sheet before the small convex portions 7 are formed on the upper nonwoven fabric 2 is not embossed, and is performed when the small convex portions 7 are formed. Embossing is not included.

As the upper layer nonwoven fabric 2, it is preferable to use, for example, an air-through nonwoven fabric (non-embossed before the formation of the small convex portions 7) which is a nonwoven fabric having a good texture. In this case, the basis weight of the air-through nonwoven fabric is about 10 to 40 g / m ² , particularly about ²⁰ to 35 g / m ² . It is preferable from the point. On the other hand, as the lower layer nonwoven fabric 3, it is preferable to use, for example, an embossed air-through nonwoven fabric, a spunbond nonwoven fabric, a spunbond / meltblown / spunbond composite nonwoven fabric, or the like. In spunbond nonwoven fabric and spunbond / meltblown / spunbond composite nonwoven fabric, embossing is generally performed in the production process. The basis weight of the lower layer nonwoven fabric 3 is preferably about 10 to 50 g / m ² , particularly about 15 to 45 g / m ² from the viewpoint of increasing the rigidity of the lower layer nonwoven fabric 3 while maintaining the texture of the top sheet 1 as a whole. Moreover, since it is used as a surface sheet, the upper layer nonwoven fabric 2 and the lower layer nonwoven fabric 3 are preferably both hydrophilically treated.

  Examples of fibers used for the upper and lower layer nonwoven fabrics 2 and 3 include synthetic fibers such as polyesters such as polyethylene (PE), polypropylene (PP), and polyethylene terephthalate (PET), and polyamides such as nylon, rayon, and cupra. The regenerated cellulose fibers and natural fibers such as cotton are not limited thereto. In addition, a core-sheath fiber using a fiber having a high melting point as a core and a fiber having a low melting point as a sheath, or a composite fiber such as a side-by-side fiber, a split fiber, or the like is also preferably used. These fibers can use 1 type (s) or 2 or more types. These fibers may be blended with a predetermined amount of a pigment such as titanium oxide as necessary to improve the concealability of the topsheet 1.

  As shown in FIG. 1, the raised portions 6 are discretely arranged and have independent island shapes. The raised portions 6 are arranged in multiple rows so as to form rows in the machine direction MD of the topsheet 1. Moreover, it arrange | positions at multiple rows so that the width direction CD of the surface sheet 1 may also form a row. The distance between the adjacent ridges 6 in the machine direction MD (the distance between the vertices of the ridges 6) is 1 to 10 mm, particularly 2 to 5 mm, so that the ridges 6 are stably formed and the ridges 6. This is preferable from the viewpoint of effectively expressing a cushion feeling and soft feeling. The interval between adjacent raised portions 6 in the width direction CD (the interval between the vertices of the raised portions 6) can be the same.

Machine direction arrangement line L _MD and the width direction arrangement line L _CD passing through the center of each ridge 6 are orthogonal to each other, these sequences lines form a grid pattern. The liquid passage holes 4 in the rectangle defined by the machine direction arrangement line L _MD and the width direction arrangement line L _CD is located. Therefore, the liquid excreted from the wearer can flow down the slope of the raised portion 6 in any of the front and rear and left and right directions, so that the liquid is quickly removed from the surface of the raised portion 6. The liquid that has flowed down quickly permeates to the absorber through the liquid passage hole 4 located between the raised portions 6. As a result, liquid residue on the skin side surface of the topsheet 1 is unlikely to occur. From this point of view, each of the liquid permeable holes 4 preferably has an area at the opening end 4a of 0.2 to ²⁰ mm ² , particularly about 0.5 to 10 mm ² . Further, the opening ratio of the liquid permeable holes 4 is preferably 5% or more, particularly preferably 7% or more, and more preferably 10 to 20%. The interval between the adjacent liquid permeation holes 4 in the machine direction MD is 1 to 10 mm, particularly 2 to 5 mm, from the viewpoint of stably forming the liquid permeation holes 4 and ensuring sufficient liquid permeability. preferable. The interval between the adjacent liquid permeable holes 4 in the width direction CD can be the same.

  From the viewpoint of further enhancing the liquid permeability and further reducing the liquid residue on the skin side surface of the topsheet 1, it is preferable that a capillary force gradient exists between the upper layer nonwoven fabric 2 and the lower layer nonwoven fabric 3. Specifically, it is preferable that the lower layer nonwoven fabric 3 has a smaller fiber diameter (fineness) than the upper layer nonwoven fabric 2. The difference in fiber diameter (fineness) between the upper and lower layer nonwoven fabrics is preferably 1 to 4 dtex, and preferably 2 to 3 dtex from the viewpoint of improving the permeability of the liquid and preventing the remaining of the liquid and preventing the liquid from returning. Further preferred. In this case, the fibers of the upper non-woven fabric 2 preferably have a fineness of 0.8 to 5 dtex, particularly 1.5 to 3.3 dtex, and the fibers of the lower non-woven fabric 3 have a fineness of 0.1 to 3.5 dtex, particularly preferably 0.00. A fineness of 5 to 2.5 dtex is preferred.

  When fibers having the same fiber diameter are used in the upper and lower layer nonwoven fabrics, the fiber density of the lower layer nonwoven fabric 3 is higher than the fiber density of the upper layer nonwoven fabric 2 in order to cause a capillary force gradient between the upper layer nonwoven fabric 2 and the lower layer nonwoven fabric 3. Is preferably increased. In this case, it is preferable that the upper and lower layer nonwoven fibers have a fineness of 0.8 to 5 dtex, particularly 1.5 to 3.3 dtex. Further, even if a hydrophilic gradient exists between the upper layer nonwoven fabric 2 and the lower layer nonwoven fabric 3, the liquid permeability is increased and the liquid residue on the skin side surface of the top sheet 1 is less likely to occur. Specifically, it is preferable that the lower layer nonwoven fabric 3 has higher hydrophilicity than the upper layer nonwoven fabric 2.

The surface sheet 1 of the present embodiment is bulky and has a soft feeling that the thickness under a load of 0.5 g / cm ² is 0.6 to ² mm, particularly 0.6 to 1.5 mm. 1 is preferable from the viewpoint of obtaining 1. The thickness under a load of 0.5 g / cm ² substantially corresponds to the thickness of the surface sheet when the surface sheet is lightly touched. Further, the basis weight of the top sheet 1 is preferably 25 to 100 g / m ² , more preferably 35 to 90 g / m ² from the viewpoints of workability and texture.

  The top sheet 1 of this embodiment is suitably manufactured by, for example, the method described below. A fiber web is inserted between the heated metal pin roll and the flat roll, and the fiber web is made into a nonwoven fabric to obtain an upper nonwoven fabric 2 and a number of small convex portions 7 are formed on the upper nonwoven fabric 2. Instead of this method, the air-through nonwoven fabric may be inserted between a heated metal convex roll and a receiving roll such as a cotton roll or a rubber roll to obtain the upper nonwoven fabric 2 having an uneven shape. Alternatively, an air-through nonwoven fabric is inserted between a pair of metal rolls that have a large number of irregularities and mesh with each other, and is subjected to steel match embossing to provide an irregular layer. The nonwoven fabric 2 may be obtained. Examples of the upper layer nonwoven fabric 2 obtained by these methods are shown in FIGS. 3 (a) and 3 (b), respectively. The upper layer nonwoven fabric shown in these drawings is merely an example of what can be used for the surface sheet of the present invention, and it is not impeded to use an upper layer nonwoven fabric other than those exemplified here.

  The upper non-woven fabric 2 shown in FIG. 3 (a) has a wavy shape, and is formed so that a large number of small convex portions 7 made of ridges face in one direction. On the other hand, in the upper layer nonwoven fabric 2 shown in FIG. 3B, a large number of individual small convex portions 7 are formed so as to be distributed in an island shape. In either case of FIG. 3 (a) and FIG. 3 (b), when comparing the fiber density between the small convex portion 7 and its peripheral region, the small convex portion 7 depends on how the small convex portion 7 is formed. There is a case where the fiber density of the convex portion 7 is higher and a case where the peripheral region is higher. From the viewpoint of enhancing the cushioning property by the small convex portions 7, it is preferable that the fiber density of the small convex portions 7 is lower than the fiber density of the peripheral region.

  A hot melt pressure-sensitive adhesive is applied to the lower surface side of the upper nonwoven fabric 2 thus obtained. Examples of the coating method include spiral coating, curtain coating, and multi-row bead coating. Next, this upper layer nonwoven fabric 2 is bonded to the lower layer nonwoven fabric 3 to obtain a laminated nonwoven fabric. The means for bonding the upper layer nonwoven fabric 2 and the lower layer nonwoven fabric 3 is not limited to the hot melt adhesive, but includes mechanical entanglement, thermal softening / melting means, and the like.

  Next, a laminated nonwoven fabric is inserted between a roll in which a large number of perforated pins are planted and a roll to which a socket that fits the perforated pins is attached to form a liquid passage hole, and the upper and lower layer nonwoven fabrics are raised. A raised portion 6 is formed. The upper layer nonwoven fabric 2 and the lower layer nonwoven fabric 3 are joined to each other around the liquid passage hole 4. In addition, since the upper and lower layer nonwoven fabrics are bonded together by the hot melt adhesive in the previous step, the upper and lower layer nonwoven fabrics are also bonded at portions other than the periphery of the liquid passage hole 4. An apparatus provided with the roll is described in, for example, Japanese Patent Application Laid-Open No. Sho 62-125061.

  The surface sheet 1 of the present embodiment can be disposed on the entire skin side of the absorbent body in the napkin. Or you may distribute only to the part in the skin side of an absorber. For example, like the napkin 10 shown in FIG. 4, only the central region 11 in the width direction of the topsheet can be configured from the topsheet 1 of the present embodiment. In this case, each side region 12 with respect to the central region 11 is preferably formed with a second raised portion having a height lower than that of the raised portion 6 formed in the central region 11. As a result, there is a difference in cushion feeling and soft feeling between the central area 11 and the side area 12, and the cushion feeling and soft feeling in the central area 11 become more prominent. In particular, when the second bulge portion formed in the side region 12 is formed at a density higher than the density of the bulge portions 6 formed in the central region 11, the cushion feeling and the soft feeling are further increased. It is preferable because it becomes remarkable.

  The side region 12 may be composed of an extended portion in which the topsheet 1 of the present embodiment that forms the central region 11 extends sideways, or the topsheet of the present embodiment that forms the central region 11. 1 may be composed of a sheet of a different material. From the viewpoint of ease of manufacture and the absence of joints due to bonding, the side region 12 is preferably composed of an extending portion of the topsheet 1 of the present embodiment that forms the central region 11. In this case, the side region 12 may be composed of both the upper layer nonwoven fabric 2 and the lower layer nonwoven fabric 3, or may be composed of either one of the upper and lower layer nonwoven fabrics. From the viewpoint of improving the texture in the side region 12, it is preferable that the side region 12 is configured such that only the upper nonwoven fabric 2 in the surface sheet 1 constituting the central region 11 extends sideways.

  In order to form the side region 12 by extending only the upper layer nonwoven fabric 2 in the surface sheet 1 constituting the central region 11 to the side, the width of the upper layer nonwoven fabric 2 is set to the lower layer nonwoven fabric 3 in various manufacturing methods of the surface sheet 1. The surface sheet 1 may be formed with respect to the overlapping portion of the two nonwoven fabrics, and the extended portion of the upper nonwoven fabric 2 may be used as the side region 12.

  As is apparent from the above description, the second raised portion formed in the side region 12 may be composed of a two-layered nonwoven fabric or may be composed of a single nonwoven fabric. When the 2nd protruding part is comprised from the non-woven fabric of 2 sheets, this 2nd protruding part may become the structure similar to the protruding part 6 in the surface sheet 1, or may differ from it. Good.

  In the side region 12, in addition to the formation of the second raised portion, the second liquid passage hole is formed between the second raised portions, so that the liquid permeability is further increased. It is preferable from the point of increasing. From this viewpoint, it is preferable that the second liquid permeation holes are formed at a density higher than the density of the liquid passage holes 4 formed in the central region 11.

  The 2nd liquid penetration hole is formed because the nonwoven fabric which comprises the side area | region 12 extends toward the absorber side (lower surface side) side from the skin side (upper surface side). The open end protrudes in the direction of the absorber. The inner wall of the second liquid permeable hole is constituted by a continuous surface from the skin side (upper surface side) surface of the nonwoven fabric constituting the side region 12. Such a structure is similar to the liquid passage hole 4 formed in the central region 11.

  The arrangement of the second raised portions and the second liquid permeable holes in the side region 12 can be the same as the arrangement of the raised portions 6 and the liquid permeable holes 4 in the topsheet 1 of the present embodiment. Moreover, the formation method of a 2nd protruding part and a 2nd liquid permeable hole can also be made to be the same as that of the protruding part 6 and the liquid permeable hole 4 in the surface sheet 1 of this embodiment.

  Next, a second embodiment of the present invention will be described with reference to FIG. For points not specifically described with respect to this embodiment, the description detailed with respect to the first embodiment is applied as appropriate. In FIG. 5, the same members as those in FIGS. 1 to 4 are denoted by the same reference numerals.

  The top sheet 1 ′ of the second embodiment shown in FIG. 5 is different from the first embodiment in the arrangement of the raised portions 6 and the liquid permeable holes 4. In the surface sheet 1 ′ of the present embodiment, a large number of flange portions 8 and groove portions 9 are alternately arranged so as not to have a flat portion. The flange portion 8 is curved in a convex shape, and the groove portion 9 is curved in a concave shape. That is, in the topsheet 1 ′ of the present embodiment, the vertices of the many ridges 6 are connected substantially linearly and continuously to form the flange 8. A groove portion 9 is formed between the adjacent flange portions 8 and 8. By forming the flange portion 8 and the groove portion 9, anisotropy can be imparted to bending characteristics (for example, bulk softness) in a direction parallel to the flange portion 8 and the groove portion 9 and a direction perpendicular thereto. It is possible to improve the fit and texture of the top sheet 1 'to the body.

  The flange portions 8 and the groove portions 9 are alternately arranged, and the groove portions 9 are formed by a continuous surface from the flange portion 8. It is preferable that the space | interval between the adjacent collar parts 8 is 1-8 mm, especially 2-5 mm. Similarly, the interval between adjacent groove portions 9 is preferably 1 to 8 mm, and particularly preferably 2 to 5 mm.

  The groove part 9 has a large number of liquid-permeable holes 4 arranged at intervals. The interval between the liquid permeable holes 4, 4 along the groove 9 is 0.4 to 40 mm, particularly 1.5 to 8 mm, which allows the liquid permeable holes 4 to be formed stably and the liquid permeability. It is preferable from the point of ensuring sufficiently. In the topsheet 1 'of the present embodiment, the liquid permeable holes 4 are arranged in a staggered pattern when the topsheet 1' is viewed in plan.

  In the surface sheet 1 ′ of the present embodiment, the extending direction of the flange portion 8 and the groove portion 9 preferably matches the longitudinal direction of the absorbent article in which the surface sheet 1 ′ of the present embodiment is used. However, it is not limited to this. The eaves part 8 and the groove part 9 may or may not coincide with the machine direction at the time of manufacturing the upper and lower layer nonwoven fabrics 2 and 3 that are raw fabrics.

  The top sheet 1 'of the present embodiment is preferably manufactured by, for example, the method described below. About the manufacturing and processing method of the upper layer nonwoven fabric 2, it is the same as that of 1st Embodiment, For example, the nonwoven fabric as shown to Fig.3 (a) and (b) demonstrated previously is formed. Next, the upper layer nonwoven fabric 2 obtained in this way and the lower layer nonwoven fabric 3 manufactured separately from this are overlapped, and the two nonwoven fabrics that are overlapped are combined with the first stamping die and the second layer. It is interposed between the pressing molds. The first pressing die is composed of a pin roll having a large number of pyramidal or conical convex pins in a row along the conveying direction of the nonwoven fabric, and the rows are arranged in multiple rows. The second pressing die is constituted by a protruding roll having a protruding portion that fits between the multi-row convex pins in the first pressing die. A stamping die having such a configuration is described in Japanese Patent Application Laid-Open No. 6-330443 relating to the earlier application of the present applicant.

  In this manufacturing method, the pin rolls are arranged in rows along the conveying direction of the upper and lower layer nonwoven fabrics, and the rows are arranged in multiple rows. On the other hand, the protruding portion of the protruding roll fits between the rows of protruding pins of the pin roll. As a result, the ridge portion 8 in which the raised portions 6 are continuous is easily formed by the ridge portion of the ridge roll, and the liquid passage hole 4 is formed by penetration into the upper and lower layer nonwoven fabric of the convex pin in the pin roll. Is done. In this case, the pin roll is heated to 60 to 260 ° C., the periphery of the liquid passage hole 4 is partially softened or partially melted, and the upper and lower layer nonwoven fabrics are joined to each other at the periphery. In addition, in order to improve the bonding property of the upper and lower layer nonwoven fabrics, hot air (for example, 60 to 260 ° C.) is sprayed on the upper and lower layer nonwoven fabrics before the overlapped upper and lower layer nonwoven fabrics are introduced between the rolls. It is also preferable to perform a preheat treatment known to those skilled in the art, such as wrapping the laminated upper and lower layer nonwoven fabrics around a preheat roll (for example, 60 to 260 ° C.).

  In this manufacturing method, prior to interposing the two non-woven fabrics overlapped between the first pressing die and the second pressing die, the two non-woven fabrics are intermittently (discontinuously) preliminarily embossed. You may join. For the embossing treatment, an embossing device composed of a heated pin roll and a flat roll is used. In this case, the interval between the pins in the width direction of the pin roll is larger than the interval in the width direction of the convex pins in the first pressing die described above or the interval in the width direction of the protrusions in the second pressing die. Keep it. After both nonwoven fabrics are embossed and joined, the above-described processing is performed with the nonwoven fabric interposed between the first and second pressing dies. As a result, the upper and lower layer nonwoven fabrics are raised in an arch shape, the first and second spaces are formed, and the liquid passage hole 4 is formed. In the surface sheet 1 ′ thus formed, the upper and lower layer nonwoven fabrics are bonded not only around the liquid passage hole 4 but also at other portions. Furthermore, the valley 7 a between the small convex portions 7, 7 formed on the upper layer nonwoven fabric 2 is in contact with the upper surface side of the lower layer nonwoven fabric 3.

  As mentioned above, although this invention was demonstrated based on the preferable embodiment, this invention is not restrict | limited to the said embodiment. For example, the arrangement of the raised portions 6 and the liquid passage holes 4 is not limited to the pattern of the above embodiment, and various patterns can be adopted. For example, in the case of the first embodiment, the raised portions 6 and / or the liquid passage holes 4 can be arranged in a staggered manner. Further, the raised portions 6 and the liquid passage holes 4 can be arranged so that the liquid passage holes 4 are always located between the adjacent raised portions 6. In the case of the second embodiment, the liquid passage holes 4 formed in the groove 9 are arranged in a staggered manner in plan view, but instead, a straight line drawn in the extending direction of the groove 9 and You may make it arrange | position the liquid passage hole 4 at each intersection of the grating | lattice formed with the straight line pulled in the orthogonal direction.

  Moreover, in each said embodiment, although the upper layer nonwoven fabric 2 and the lower layer nonwoven fabric 3 can be made into the same dimension, it replaces with this, and the dimension of the upper layer nonwoven fabric 2 is smaller about the longitudinal direction than the lower layer nonwoven fabric 3 from an economical viewpoint. And you may distribute the upper layer nonwoven fabric 2 only in the center part of the longitudinal direction of the lower layer nonwoven fabric 3. FIG.

  Moreover, although the said embodiment is an example which applied the surface sheet of this invention to the sanitary napkin, this invention is applied also to other absorptive articles, for example, a panty liner, a cage sheet, an incontinence pad, a disposable diaper etc. The same applies.

It is a schematic diagram which shows the state which looked at the surface sheet of the absorbent article of this invention. It is a schematic diagram of the II-II line cross section in FIG. It is a schematic diagram which shows the state of the upper layer nonwoven fabric in the process of manufacturing the surface sheet of this invention. It is a perspective view which shows the sanitary napkin using the surface sheet of this invention. It is a schematic diagram (figure 1 equivalent view) which shows the state which looked at 2nd Embodiment of the surface sheet of the absorbent article of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,1 'Surface sheet 2 Upper layer nonwoven fabric 3 Lower layer nonwoven fabric 4 Liquid passage hole 5a 1st space 5b 2nd space 6 Raised part 7 Small convex part 8 Gutter part 9 Groove part

Claims (7)

In the surface sheet of an absorbent article comprising a laminated nonwoven fabric having an upper layer nonwoven fabric disposed on the skin side and a lower layer nonwoven fabric disposed on the absorber side,
In the laminated nonwoven fabric, a large number of liquid passage holes penetrating the laminated nonwoven fabric are formed, and the upper layer nonwoven fabric and the lower layer nonwoven fabric are joined to each other around the liquid passage hole,
The upper layer nonwoven fabric and the lower layer nonwoven fabric are both arched toward the skin side between the liquid passage holes, and a space is formed between the lower layer nonwoven fabric and the upper layer nonwoven fabric and the lower layer nonwoven fabric, respectively. A large number of raised portions that are raised toward the
The top sheet of the absorbent article in which the arched portion of the upper non-woven fabric is a smaller convex portion than the arched portion of the lower non-woven fabric.   The top sheet of an absorbent article according to claim 1, wherein the rigidity of the lower layer nonwoven fabric is higher than that of the upper layer nonwoven fabric.   The top sheet of an absorbent article according to claim 1 or 2, wherein the plurality of raised portions formed on the top sheet are discretely arranged and have independent island shapes.   The top sheet of the absorbent article according to any one of claims 1 to 3, wherein a plurality of raised portions formed on the top sheet are continuously connected at the tops thereof to form a bowl shape. In the absorbent article in which the surface sheet is arranged on the skin side of the absorber,
The central region in the width direction of the top sheet is composed of the top sheet according to claim 1,
In each side region with respect to the central region in the surface sheet, the second bulge portion having a height lower than that of the bulge portion formed in the central region is higher than the density of the bulge portions formed in the central region. Absorbent article formed of.   The absorbent article according to claim 5, wherein the second liquid passage holes are formed in each side region with respect to the central region of the surface sheet at a density higher than the density of the liquid passage holes formed in the central region. The absorbent article according to claim 5 or 6, wherein each side region in the surface sheet is formed by extending an upper layer nonwoven fabric or a lower layer nonwoven fabric in the surface sheet according to claim 1 constituting the center region.

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