KR101138114B1 - Topsheet for absorbent article - Google Patents

Abstract

The surface sheet 1 has an upper nonwoven fabric 2 and a lower nonwoven fabric 3. The surface sheet 1 is formed with a plurality of liquid through holes 4 penetrating the surface sheet 1. The upper and lower layer nonwoven fabrics are bonded to each other around the liquid passage hole 4. Both the upper and lower nonwoven fabrics are raised toward the skin side between the liquid through holes 4, and spaces 5a and 5b are formed respectively below the lower nonwoven fabric and between the upper nonwoven fabric and the lower nonwoven fabric. In addition, a plurality of raised portions 6 which are raised toward the skin side are formed. In the lower layered nonwoven fabric 3, many small convex parts 7 are formed in the part which raised in arch shape. Alternatively, the arcuate portion of the upper nonwoven fabric 2 is a small convex portion 7 which is smaller than the arcuate portion of the lower layer nonwoven fabric 3.

Absorbent article, surface sheet, sanitary napkin, liquid through hole

Description

Surface sheet of absorbent article {TOPSHEET FOR ABSORBENT ARTICLE}

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic diagram which shows the state which looked obliquely at 1st Embodiment of the surface sheet of the absorbent article of this invention.

It is a schematic diagram of the cross section of the II-II line | wire of FIG.

Figure 3 is a schematic diagram showing the state of the lower layer nonwoven fabric in the process of producing the surface sheet of the present invention.

Figure 4 is a perspective view showing a sanitary napkin using the surface sheet of the present invention.

It is a schematic diagram (FIG. 1 correspondence figure) which shows the state which looked at the 2nd Embodiment of the surface sheet of the absorbent article of this invention at an angle.

It is a schematic diagram (FIG. 1 correspondence figure) which shows the state which looked at the 3rd Embodiment of the surface sheet of the absorbent article of this invention at an angle.

FIG. 7 is a schematic view of the X-ray cross section of FIG. 6. FIG.

It is a schematic diagram (FIG. 1 correspondence figure) which shows the state which looked at the 4th Embodiment of the surface sheet of the absorbent article of this invention at an angle.

The present invention relates to a surface sheet for use in absorbent articles such as sanitary napkins, panty liners, secretion sheets, incontinence pads, disposable diapers, and the like. The present invention also relates to an absorbent article having the surface sheet.

As a surface sheet of an absorbent article, it is known that two sheets of sheet material are overlapped to form openings therebetween and convex portions are formed between the openings. For example, the present applicant has previously proposed a surface sheet of an absorbent article composed of at least two layers of nonwoven fabrics, having a plurality of openings, and wherein each nonwoven fabric is bonded to each other at the periphery of the openings. 10-80445). In this surface sheet, a plurality of ridge portions and groove portions are alternately arranged so as not to have a flat portion, and the openings are arranged at intervals in the groove portion. According to this surface sheet, the softness and the soft feeling are improved, and the concealability of the absorbed liquid is improved.

In addition, the present applicant has proposed a two-layered surface sheet having a plurality of convex portions and concave portions (see JP-A-2002-238947). The surface sheet has a skin-facing surface made of a nonwoven fabric, and openings are formed in the top portion of the convex portion, in the vicinity of the convex portion, or in the bottom portion of the concave portion. A space | gap is formed between two layers. This surface sheet is hard to remain liquid and does not feel sticky.

In addition, the fluid layer located on the skin side has a liquid permeable surface sheet and a liquid permeable support sheet superimposed on the back side thereof, and liquid through holes penetrating both sheets are formed. A surface sheet of an absorbent article provided with a hole array region lined along a line has been proposed (see Japanese Patent Laid-Open No. 2002-253610). In this surface sheet, the surface sheet and the support sheet are not substantially bonded to each other in regions separated from each other by the hole array region. This surface sheet is soft and has cushioning so that it is soft to the skin.

Furthermore, the surface sheet of the absorbent article in which the polyethylene film was doubled, the seal part was provided in the middle, the convex part was formed, the air or the foamed elastic body was sealed in the convex part, and the through-hole was formed in the adjacent position between the convex parts. A Japanese Utility Model Model No. Hei 2-17126 is also proposed. According to this surface sheet, the pressure applied to the absorber decreases, so that wet back of the liquid is prevented.

The present invention provides a surface sheet of an absorbent article composed of a laminated nonwoven fabric having an upper nonwoven fabric disposed on the skin side and a lower nonwoven fabric disposed on the absorbent side. The laminated nonwoven fabric is formed with a plurality of liquid through holes penetrating it, and the upper nonwoven fabric and the lower nonwoven fabric are joined to each other around the liquid through hole. The upper nonwoven fabric and the lower nonwoven fabric are both arcuately raised toward the skin side between the liquid through holes, and a space is formed between the lower nonwoven fabric and the upper nonwoven fabric and the lower nonwoven fabric, respectively. The ridge is formed in the surface sheet.

In the lower layer nonwoven fabric, many small convex portions are formed in an arcuate portion. Alternatively, the arcuate portions of the upper nonwoven fabric are smaller convex portions than the arcuate portions of the lower nonwoven fabric.

The present invention also provides an absorbent article in which the surface sheet is disposed on the skin side of the absorbent body, wherein the central region in the width direction of the surface sheet is constituted by the surface sheet. In each side region of the surface sheet with respect to the center region, the second ridge portion having a height lower than that of the ridge portion formed in the center region is formed at a density higher than the density of existence of the ridge portion formed in the center region.

The present invention provides a surface sheet of an absorbent article in which cushioning and softness are improved and liquid backflow is less likely to occur than the surface sheet of the prior art.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated, referring drawings based on the preferable embodiment. The schematic diagram of the state which looked at the surface sheet of the absorbent article of this invention at an angle is shown in FIG. 1, and the schematic diagram of the II-II cross section of FIG. 1 is shown in FIG. The surface sheet 1 of this embodiment is used as a surface sheet of a sanitary napkin which is an example of an absorbent article. The surface sheet 1 consists of a laminated nonwoven fabric having an upper layer nonwoven fabric 2 disposed on the skin side of the wearer and a lower layer nonwoven fabric 3 disposed on the absorber side of the napkin when the surface sheet 1 is embedded in the napkin. . The surface sheet 1 is formed with a plurality of liquid through holes 4 penetrating both the upper nonwoven fabric 2 and the lower nonwoven fabric 3. The liquid through hole 4 is formed surrounded by a laminated nonwoven fabric extending from the skin side (upper surface side) of the surface sheet 1 toward the absorber side (lower surface side). The open end 4a of the liquid passage hole 4 protrudes in the direction of an absorber not shown. The inner wall of the liquid passage hole 4 is composed of a continuous surface on the surface on the skin side (upper surface side) of the surface sheet 1.

The upper nonwoven fabric 2 and the lower nonwoven fabric 3 are joined at least in the periphery of the liquid through-hole 4, ie, the open end 4a of the liquid through-hole 4, and its vicinity. In portions other than the periphery of the liquid passage hole 4, the upper nonwoven fabric 2 and the lower nonwoven fabric 3 may not be substantially bonded or may be joined. Bonding means that the fibers constituting the upper and lower layer nonwoven fabrics 2 and 3 are mechanically entangled, thermally softened / 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 completely separated from each other, and 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 where it is easily separated by a force applied to (1).

Between the liquid through holes 4 and 4, both the upper nonwoven fabric 2 and the lower nonwoven fabric 3 are raised in an arc shape toward the skin side. And the 1st space 5a is formed between the upper layer nonwoven fabric 2 and the lower layer nonwoven fabric 3, and the 2nd space 5b is formed below the lower layer nonwoven fabric 3, respectively. Furthermore, when looking at the whole surface sheet 1, many ridges 6 which protruded toward the skin side are formed in the said surface sheet 1. As shown in FIG. The ridge part 6 is comprised from the upper layer nonwoven fabric 2 and the lower layer nonwoven fabric 3 which respectively protruded arcuate toward the skin side.

Furthermore, as shown in FIG. 2, the lower layered nonwoven fabric 3 is provided with the many small convex part 7 in the part which raised in arch shape. The small convex part 7 is formed so that the lower layer nonwoven fabric 3 may deform | transform like a small wave. The convex tip of the small convex portion 7 is in contact with or separated from the lower surface side of the upper nonwoven fabric 2. In particular, when the tip of the convex portion of the small convex portion 7 is in contact with the lower surface side of the upper nonwoven fabric 2, there is an advantage that the transferability of the liquid from the upper nonwoven fabric 2 to the lower nonwoven fabric 3 becomes good. In addition, there is an advantage that the arcuate shape of the upper nonwoven fabric 2 is supported by the small convex portion 7 and is not easily deformed.

Thus, the ridge 6 has a two-layer structure of the upper nonwoven fabric 2 and the lower nonwoven fabric 3, and since the first space 5a is formed between both nonwoven fabrics, the body pressure of the wearer is increased from the surface sheet 1 ), The arch shape by the upper layer nonwoven fabric 2 is deformed first, and then the arch shape by the lower layer nonwoven fabric 3 is deformed. Therefore, the surface sheet 1 of this embodiment is excellent in a cushion feeling and a soft feeling. Furthermore, it is difficult for the liquid once absorbed by the absorber (not shown) to flow back to the surface sheet 1 side. That is, so-called wetback is difficult to occur.

In addition, even if the wearer's body pressure is applied to the surface sheet 1, a large number of small convex portions 7 formed in the lower layer nonwoven fabric 3 act as a supporting portion for preventing deformation of the upper layer nonwoven fabric 2, thereby maintaining the arch shape. Easier Therefore, the ridge shape is stably maintained when viewed from the entire ridge 6. As a result, the surface sheet 1 in this embodiment can reduce the contact area between the wearer's skin and the skin-side surface of the surface sheet 1, preventing the occurrence of discomfort and providing breathability. It can be kept well.

It is preferable that the lower layer nonwoven fabric 3 is comprised with the high rigidity nonwoven fabric from a viewpoint of preventing the deformation | transformation of the upper layer nonwoven fabric 2 by the small convex part 7 formed in the lower layer nonwoven fabric 3. On the other hand, the upper layer nonwoven fabric 2 is also preferably composed of a nonwoven fabric having high rigidity, but from the viewpoint of preventing the deformation of the upper layer nonwoven fabric 2, it is easy to lower the texture of the nonwoven fabric. Therefore, in the surface sheet 1 of this embodiment, the rigidity of the lower layer nonwoven fabric 3 is made higher than that of the upper layer nonwoven fabric 2, and the arched deformation is prevented by the lower layer nonwoven fabric 3, and the upper layer nonwoven fabric 2 is favorable. The texture is expressed.

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 overall texture of the surface sheet 1 tends to be lowered. In addition, it cannot be said that it is advantageous in terms of manufacturing cost. Therefore, in this embodiment, it is preferable to use the embossed nonwoven fabric as the lower layer nonwoven fabric 3. On the other hand, as for the upper layer nonwoven fabric 2, it is preferable to use the nonwoven fabric which is not embossed from a viewpoint of making a texture good.

Specifically, as the upper nonwoven fabric 2, it is preferable to use, for example, an air-through nonwoven fabric (not embossed), which is a nonwoven fabric having a good feel. In this case, the basis weight of the breathable nonwoven fabric is preferably 10 to 40 g / m ² , particularly about 20 to 35 g / m ² , in view of the arch formability, texture, manufacturing cost, etc. of the upper nonwoven fabric 2. As the lower layer nonwoven fabric, for example, it is preferable to use an embossed breathable nonwoven fabric, a spunbonded nonwoven fabric, a spunbond / meltblown / spunbond composite nonwoven fabric, and the like. In spunbond nonwoven fabrics and spunbond / melt blown / spunbond composite nonwoven fabrics, embossing is generally carried out in the manufacturing process. The basis weight of the lower layer nonwoven fabric 3 is preferably 10 to 50 g / m ² , particularly 15 to 45 g / m ² , in view of increasing the rigidity of the lower layer nonwoven fabric 3 while maintaining the texture of the entire surface sheet 1. Moreover, since it is used as a surface sheet, it is preferable that both the upper layer nonwoven fabric 2 and the lower layer nonwoven fabric 3 were hydrophilized.

As the fibers used for the upper and lower layer nonwoven fabrics (2, 3), for example, the synthesis of polyester such as polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET) and polyamide such as nylon Regenerated cellulose fibers such as fibers, rayon and cuprammonium, and natural fibers such as cotton, but are not limited to these. In addition, composite fibers such as a core sheath fiber, a side-by-side fiber, a split fiber, and the like having a high melting point as a core and a low melting point as a sheath are also preferably used. These fibers can use 1 type (s) or 2 or more types. You may mix | blend a predetermined amount of pigments, such as a titanium oxide, with these fibers, and may improve the concealability of the surface sheet 1. As shown in FIG.

As shown in Fig. 1, the ridges 6 are discretely arranged to form independent island shapes. Each ridge 6 is arranged in rows as if lined up in the machine direction MD of the surface sheet 1. In addition, they are arranged in a row in a row in the width direction (CD) of the surface sheet (1). The distance between the adjacent ridges 6 in the machine direction MD (the interval between the vertices of the ridges 6) is 1 to 10 mm, particularly 2 to 5 mm, to stably form the ridges 6. And it is preferable at the point which expresses the cushion feeling and soft feeling by the raised part 6 effectively. The intervals (intervals between the vertices of the raised portions 6) of the adjacent raised portions 6 in the width direction CD can also be the same.

The 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, and these arrangement lines form a lattice shape. And the liquid permeation hole 4 is located in the rectangle drawn by the machine direction arrangement line L _MD and the width direction arrangement line L _MD . Therefore, since the liquid discharged from the wearer can flow along the inclined surface of the ridge 6 in any of the front, rear, and left and right directions, the liquid is quickly removed from the surface of the ridge 6. The liquid which flows out is quickly permeated to the absorber through the liquid passage hole 4 located between the ridges 6. As a result, liquid residue hardly occurs on the skin side surface of the surface sheet. From this point of view, each liquid permeation hole 4 preferably has an area in the open end 4a of 0.2 to 20 mm ² , particularly about 0.5 to 10 mm ² . In addition, the porosity of the liquid through hole 4 is preferably 5% or more, particularly 7% or more, and particularly preferably 10 to 20%. The distance between adjacent liquid permeation holes 4 in the machine direction MD is 1 to 10 mm, particularly 2 to 5 mm, for stably forming the liquid permeation holes 4 and for ensuring sufficient permeability of the liquid. Preferred at The space | interval of the adjacent liquid permeation hole 4 in the width direction CD can also be made the same.

It is preferable that a capillary force gradient exists between the upper nonwoven fabric 2 and the lower nonwoven fabric 3 from the viewpoint of further improving the liquid permeability and further preventing liquid residue on the skin-side surface of the surface sheet. Do. 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, more preferably 2 to 3 dtex in terms of improving liquid permeability, preventing liquid residue and preventing liquid backflow. . In this case, it is preferable that the fibers of the upper layer nonwoven fabric 2 have a fineness of 0.8 to 5 dtex, particularly 1.5 to 3.3 dtex, and the fibers of the lower layer nonwoven fabric 3 have a fineness of 0.1 to 3.5 dtex, especially 0.5 to 2.5 dtex. Do.

When using fibers of the same fiber diameter as 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 have a maternal force gradient between the upper layer nonwoven fabric 2 and the lower layer nonwoven fabric 3. It is preferable to make it high. In this case, the fibers of the upper and lower layers are preferably 0.8 to 5 dtex, particularly 1.5 to 3.3 dtex. In addition, even if a hydrophilic gradient exists between the upper nonwoven fabric 2 and the lower nonwoven fabric 3, the liquid permeability is increased, and liquid residue on the skin side surface of the surface 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.

It is preferable that the surface sheet 1 of this embodiment is 0.6-2 mm in thickness under 0.5 g / cm <^2> load, especially 0.6-1.5 mm in the point which is bulky and the surface sheet 1 which improved the soft feeling is obtained. . The thickness under a load of 0.5 g / cm ² is almost equivalent to the thickness of the surface sheet when lightly touching the surface sheet. In addition, the basis weight of the topsheet (1) processability and texture is that the point 25 ~ 100g / m ² are preferred, and more preferably from 35 ~ 90g / m ² in such.

The surface sheet 1 of this embodiment is suitably manufactured by the method demonstrated below, for example. A fiber web is inserted between a heated metal pin roll and a flat roll to nonwoven fabric the fiber web to obtain a lower layer nonwoven fabric (3) and at the same time a plurality of lower layer nonwoven fabrics (3). Small convex portions are formed. Instead of this method, the breathable nonwoven fabric may be inserted between a heated metal convex roll and a back-up roll such as a cotton roll or a rubber roll to obtain a lower layer nonwoven fabric 3 provided with an uneven shape. Alternatively, the breathable nonwoven fabric may be inserted between a set of rolls made of metal that are engaged with each other while a large number of irregularities are formed, and then subjected to steel matching embossing to obtain the lower layer nonwoven fabric 3 provided with the irregularities. Examples of the lower layer nonwoven fabric 3 obtained by these methods are shown in Figs. 3A and 3B, respectively. The lower layer nonwoven fabric shown in these figures is only an example of what can be used for the surface sheet of this invention, and using a lower layer nonwoven fabric other than what is illustrated here is not restrict | limited at all.

The lower layer nonwoven fabric 3 shown in FIG. 3 (a) has a wavelike shape, and a large number of small convex portions 7 formed of raised portions are formed to face one direction. On the other hand, in the lower layer nonwoven fabric 3 shown in FIG.3 (b), many independent small convex parts 7 each are formed so that it may distribute in island shape. In any case of FIGS. 3 (a) and 3 (b), when the fiber density between the small convex portion 7 and its peripheral region is compared, the small convex portion 7 is formed depending on how the small convex portion 7 is formed. In the case of the portion 7, the fiber density increases, and in contrast, the peripheral region may increase. It is preferable that the fiber density of the small convex part 7 is lower than the fiber density of the peripheral area from the viewpoint of improving the cushioning property by the small convex part 7.

The hot-melt adhesive is coated on the upper surface side of the lower nonwoven fabric 3 thus obtained. Coating methods include, for example, spiral coating, curtain coating, multi-row bead coating, and the like. Next, the lower layer nonwoven fabric 3 is bonded to the upper layer nonwoven fabric 2 to obtain a laminated nonwoven fabric.

Next, a laminated nonwoven fabric is inserted between a roll having a plurality of perforating pins and a roll with a socket fitted with the perforating pin to form a liquid through hole, and at the same time, the upper and lower layer nonwoven fabrics are raised to raise the ridges. (6) is formed. The upper nonwoven fabric 2 and the lower 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 foregoing step, the upper and lower layer nonwoven fabrics are also joined in portions other than the periphery of the liquid passage hole 4. The apparatus provided with the said roll is described, for example in Unexamined-Japanese-Patent No. 62-125061.

The surface sheet 1 of this embodiment can arrange | position this to the skin side whole surface of the absorber in a napkin. Or you may arrange | position only to a part in the skin side of an absorber. For example, like the napkin 10 shown in FIG. 4, only the center area | region 11 of the width direction in a surface sheet can be comprised by the surface sheet 1 of this embodiment. In this case, it is preferable that each side region 12 with respect to the center region 11 is 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, a difference in cushioning and softness occurs in the central region 11 and the side region 12, and the cushioning and softness in the central region 11 become more remarkable. In particular, when the second ridge formed in the side region 12 is formed at a density higher than the density of the ridge 6 formed in the central region 11, the cushioning and softness become more remarkable. desirable.

The side region 12 may be comprised by the extension part which the surface sheet 1 of this embodiment which forms the center area | region 11 extended to the side, or the surface of this embodiment which forms the center area | region 11 It may be comprised from the sheet | seat of material separate from the sheet | seat 1. The side region 12 is preferably composed of an extension of the surface sheet 1 of the present embodiment forming the central region 11 in that there is no seam due to ease of manufacture or bonding. In this case, the side area | region 12 may be comprised by both the upper layer nonwoven fabric 2 and the lower layer nonwoven fabric 3, or may be comprised by either one of the upper and lower layer nonwoven fabrics. From the viewpoint of improving the feel in the side region 12, the side region 12 is configured such that only the upper nonwoven fabric 2 in the surface sheet 1 constituting the center region 11 extends laterally. desirable.

Only the upper nonwoven fabric 2 in the surface sheet 1 constituting the center region 11 extends laterally to form the side region 12. In the various manufacturing methods of the surface sheet 1 described later, the upper layer The width of the nonwoven fabric 2 is made larger than the width of the lower layer nonwoven fabric 3, the surface sheet 1 is formed in the portion where both nonwoven fabrics overlap, and the extended portion of the upper nonwoven fabric 2 is formed in the lateral region 12. It may be used as.

As can be seen from the above description, the second ridge formed in the side region 12 may be composed of two nonwoven fabrics overlapped with each other, or may be composed of one nonwoven fabric. When the 2nd ridge part is comprised from the nonwoven fabric which overlapped with 2 sheets, the said 2nd ridge part may be the same structure as the ridge part 6 in the surface sheet 1, or may differ from it.

In the side region 12, it is preferable that a second liquid passage hole is formed between the second ridges in addition to the formation of the second ridges in order to further enhance the liquid permeability. From this point of view, it is preferable that the second liquid through hole is formed at a density higher than the density of existence of the liquid through hole 4 formed in the central region 11.

The second liquid permeation hole is formed by the nonwoven fabric constituting the lateral region 12 extending from the skin side (upper surface side) toward the absorber side (lower surface side). The open end protrudes in the direction of the absorbent body. The inner wall of the second liquid permeation hole is composed of a continuous surface on the skin side (upper surface side) surface of the nonwoven fabric constituting the lateral region 12. This structure is the same as the liquid through hole 4 formed in the central region 11.

The arrangement of the second raised portion and the second liquid penetrating hole in the lateral area 12 is different from the arrangement of the raised portion 6 and the liquid penetrating hole 4 in the surface sheet 1 of the present embodiment. The same can be done. In addition, the method of forming the second raised portion and the second liquid penetrating hole can be the same as that of the raised portion 6 and the liquid penetrating hole 4 in the surface sheet 1 of the present embodiment.

Next, 2nd-4th embodiment of this invention is described, referring FIGS. 5-8. The description mentioned above regarding 1st Embodiment applies suitably about the point which does not describe in particular about these embodiment. 5-8, the same code | symbol is attached | subjected to the same member as FIG.

As for the surface sheet 1 of 2nd Embodiment shown in FIG. 5, arrangement | positioning of the ridge | bulb part 6 and the liquid permeation hole 4 differ from 1st Embodiment. In the surface sheet 1 of the present embodiment, a plurality of raised portions 8 and grooves 9 are alternately arranged so as not to have a flat portion. The raised portion 8 is curved in a convex shape, and the groove 9 is curved in a concave shape. In other words, in the surface sheet 1 of the present embodiment, the vertices of the plurality of ridges 6 are almost linear and continuously connected to form the raised portions 8. The grooves 9 are formed between the adjacent raised portions 8, 8. By forming the raised portion 8 and the groove portion 9, the bending characteristics (for example, bulk softness, etc.) in the direction parallel to the raised portion 8 and the groove portion 9 and in a direction perpendicular to them. It is possible to impart anisotropy and to improve the fit and texture of the surface sheet 1 to the body.

The raised portion 8 and the groove portion 9 are alternately arranged, and the groove portion 9 is formed as a continuous surface in the raised portion 8. The spacing between neighboring raised portions 8 is preferably 1 to 8 mm, in particular 2 to 5 mm. Furthermore, it is preferable that the space | interval between neighboring groove parts 9 is also 1-8 mm, especially 2-5 mm.

The groove portion 9 has a plurality of liquid permeation holes 4 arranged at intervals. The gap between the liquid penetrating holes 4 and 4 along the groove 9 is 0.4 to 40 mm, in particular 1.5 to 8 mm, to ensure the liquid penetrating hole 4 can be stably formed and to ensure sufficient liquid permeability. It is preferable at the point. In the surface sheet 1 of this embodiment, when the said surface sheet 1 is planarly viewed, the liquid permeation hole 4 is arrange | positioned in the shape of a hound's tooth check.

In the surface sheet 1 of the present embodiment, the direction in which the raised portions 8 and the grooves 9 extend preferably coincides with the longitudinal direction of the absorbent article in which the surface sheet 1 of the present embodiment is used. But it is not limited to this. The embossed portion 8 and the groove portion 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, which are fabrics.

The surface sheet 1 of this embodiment is suitably manufactured by the method demonstrated below, for example. The manufacturing and processing method of the lower layer nonwoven fabric 3 is the same as that of 1st Embodiment, for example, forms a nonwoven fabric as shown to FIG. 3 (a) and (b) mentioned above. Next, the lower layer nonwoven fabric 3 obtained in this way and the upper layer nonwoven fabric 2 manufactured separately from this are piled up, and two overlapping nonwoven fabrics are interposed between a 1st embossing frame and a 2nd embossing frame. The first embossing mold is composed of pin rolls having a plurality of convex pins in the shape of pyramids or cones in a row shape along the conveying direction of the nonwoven fabric, and the rows are formed side by side in several rows. The second embossing mold is composed of a projection roll having a projection portion sandwiched between a plurality of rows of convex pins in the first embossing mold. The embossing mold having such a configuration is described in Japanese Patent Laid-Open No. 6-330443 according to the present applicant.

In the present production method, the pin rolls are formed by convex fins arranged along the conveying direction of the upper and lower layer nonwoven fabrics, and the rows are formed side by side in several rows. On the other hand, the protrusion roll is sandwiched between the rows of the protrusions of each convex pin of the pin roll. As a result, the raised part 8 in which the ridge | bulb 6 lined up is formed easily by the protrusion part of a protrusion roll, and the needle penetrates into the upper and lower layer nonwoven fabric of the convex pin in a pin roll, and the liquid passage hole 4 is carried out. Is formed. In this case, the pin roll is heated to 60-260 degreeC, the softening or partial melting of the periphery of the liquid through-hole 4 is carried out, and the upper and lower layer nonwoven fabric is joined together in the said 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 blown into the overlapped upper and lower layer nonwoven fabrics, for example, before the stacked upper and lower layer nonwoven fabrics are introduced between the rolls. It is also preferable to perform a preheating treatment known to those skilled in the art, such as winding the superimposed upper and lower layer nonwoven fabrics on a preheat roll (for example, 60 to 260 ° C).

In this manufacturing method, before superimposing two nonwoven fabrics between a 1st embossing frame and a 2nd embossing frame, you may emboss and join both nonwoven fabrics intermittently (discontinuously) beforehand. The embossing apparatus which consists of a heated pin roll and a flat roll is used for the embossing process. In this case, the space | interval of the pin of the width direction in a pin roll is made larger than the space | interval of the width direction of the convex pin in the above-mentioned 1st embossing frame, and the space | interval of the width direction of the protrusion part in a 2nd embossing frame. Do it. After both nonwoven fabrics are embossed and joined, the above-described processing is performed between the first embossing mold and the second embossing mold. As a result, the upper and lower nonwoven fabrics are raised in an arc shape to form the first and second spaces, and the liquid passage holes 4 are formed. In the surface sheet 1 thus formed, not only the periphery of the liquid passage hole 4 but also the upper and lower layer nonwoven fabrics are bonded to other portions. Further, the tip of the convex portion of the small convex portion 7 formed in the arcuate portion of the lower nonwoven fabric 3 is in contact with the lower surface side of the upper nonwoven fabric 2.

The surface sheet 1 of 3rd Embodiment shown to FIG. 6 and FIG. 7 has an arcuate part in the upper layer nonwoven fabric 2 smaller than the arcuate part in the lower layer nonwoven fabric 3. A small convex portion 7 is formed. The small convex portions 7 are discretely arranged over the entire upper layer nonwoven fabric 2 to form independent island shapes. The surface sheet 1 of this embodiment which has such a structure is similar to the structure of the surface sheet of 1st embodiment. However, the surface sheet 1 of this embodiment is a form which made the upper layer nonwoven fabric and the lower layer nonwoven fabric of the surface sheet of 1st embodiment upside down. The description concerning 1st Embodiment applies suitably about the point which does not describe in particular about this embodiment.

The valley portion 7b (described as 7b in FIG. 7) existing between the adjacent small convex portions 7 and 7 is in contact with or separated from the upper surface side of the lower layer nonwoven fabric 3. In particular, when the valley portion 7b is in contact with the upper surface side of the lower layer nonwoven fabric 3, there is an advantage that the liquid transferability from the upper layer nonwoven fabric 2 to the lower layer nonwoven fabric 3 becomes good. In addition, there is an advantage that the shape of the small convex portion 7 is supported by the arched shape of the lower layer nonwoven fabric 3 and is difficult to be deformed.

Since the surface sheet 1 comes into contact with the skin at the tops of the plurality of small convex portions 7, the above-mentioned cushioning feeling and soft feeling are further remarkable by the body pressure dispersion effect. Furthermore, since the arch shape (small convex portion 7) of the upper layer nonwoven fabric 2 is smaller than that of the lower layer nonwoven fabric 3, the contact area between the surface sheet 1 and the skin becomes smaller, resulting in excellent freshness and smoothness.

In addition, when the rigidity of the lower nonwoven fabric 3 is higher than the rigidity of the upper nonwoven fabric 2, even if the wearer's body pressure is applied to the surface sheet 1, the arch shape of the lower nonwoven fabric 3 prevents deformation of the ridge 6. Since it acts as a supporting part, the shape of the ridge is stably maintained when viewed as the entire ridge 6. As a result, the surface sheet 1 in this embodiment can reduce the contact area between the wearer's skin and the skin-side surface of the surface sheet 1, preventing the occurrence of discomfort and providing breathability. It can be kept well. In addition, it is preferable that the upper layer nonwoven fabric 2 also consists of a high rigid nonwoven fabric from a viewpoint of keeping arch shape stable. However, when the rigidity of the upper nonwoven fabric 2 is made high, the texture of a nonwoven fabric will fall easily. Therefore, in the surface sheet 1 of this embodiment, the rigidity of the lower layer nonwoven fabric 3 is raised more than the upper layer nonwoven fabric 2, and the arched deformation is prevented by the lower layer nonwoven fabric 3, and the upper layer nonwoven fabric 2 is favorable. The texture is expressed.

In order to increase the rigidity of the lower layer nonwoven fabric 3, it is preferable to use the embossed nonwoven fabric as the lower layer nonwoven fabric 3. On the other hand, as for the upper layer nonwoven fabric 2, it is preferable to use the nonwoven fabric which is not embossed from a viewpoint of making a texture good. In addition, not being embossed here means that the sheet | seat before the small convex part 7 is formed in the upper layer nonwoven fabric 2 is not embossed, and the embossing performed at the time of forming the small convex part 7 is carried out. Is not included.

The surface sheet 1 of this embodiment is suitably manufactured according to the method demonstrated below, for example. First, the upper layer nonwoven fabric 2 of the form shown to FIG. 3 (a) and (b), respectively is obtained by the method similar to the manufacturing method of the lower layer nonwoven fabric of 1st Embodiment mentioned above. In addition, the upper nonwoven fabric shown in these figures is only an example of what can be used for the surface sheet of this invention, It is not restrict | limited at all to use upper nonwoven fabrics other than what is illustrated here.

The hot melt adhesive is coated on 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, the upper nonwoven fabric 2 is bonded to the lower nonwoven fabric 3 to obtain a laminated nonwoven fabric. In addition, the joining means of the upper layer nonwoven fabric 2 and the lower layer nonwoven fabric 3 is not limited to a hot melt adhesive, but also includes mechanical entanglement, thermal softening and melting means.

Next, a laminated nonwoven fabric is inserted between a roll having a plurality of punched pins and a roll with a socket fitted with the punched pin to form a liquid through hole, and a raised portion 6 is formed by raising the upper and lower layered nonwoven fabrics. do. In addition, the upper nonwoven fabric 2 and the lower nonwoven fabric 3 are bonded 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 foregoing step, the upper and lower layer nonwoven fabrics are also joined in portions other than the periphery of the liquid passage hole 4. Such a process is the same as what was already demonstrated about the manufacturing method of the surface sheet of 1st embodiment mentioned above.

As for the surface sheet 1 of 4th Embodiment shown in FIG. 8, arrangement | positioning of the ridge | bulb part 6 and the liquid permeation hole 4 differ from 3rd Embodiment. In the surface sheet 1 of the present embodiment, a plurality of raised portions 8 and grooves 9 are alternately arranged so as not to have a flat portion. The raised portion 8 is curved in a convex shape, and the groove 9 is curved in a concave shape. In other words, in the surface sheet 1 of the present embodiment, the vertices of the plurality of ridges 6 are substantially straight and continuously arranged to form the raised portions 8. The surface sheet 1 of this embodiment which has such a structure is similar to the structure of the surface sheet of 2nd embodiment. However, the surface sheet 1 of this embodiment is a form which made the upper layer nonwoven fabric and the lower layer nonwoven fabric of the surface sheet of 2nd embodiment upside down. The description concerning 2nd Embodiment applies suitably about the point which does not describe in particular about this embodiment.

The surface sheet 1 of this embodiment is appropriately manufactured by the method demonstrated below, for example. The manufacturing and processing method of the upper layer nonwoven fabric 2 is the same as the manufacturing and processing method of the lower layer nonwoven fabric of 2nd Embodiment, for example, forms a nonwoven fabric as shown to FIG. 3 (a) and (b) mentioned above. do. Next, the upper nonwoven fabric 2 obtained in this way and the lower nonwoven fabric 3 manufactured separately from this are piled up, and the two overlapping nonwoven fabrics are interposed between a 1st embossing frame and a 2nd embossing frame. As a result, the surface sheet 2 is obtained. The embossing mold used, the manufacturing conditions using the said embossing mold, etc. can be made similar to 2nd Embodiment.

As mentioned above, although this invention was demonstrated based on preferable embodiment, this invention is not limited to the said embodiment. For example, arrangement | positioning of the ridge | bulb part 6 and the liquid passage hole 4 is not limited to the pattern of the said embodiment, A various pattern can be employ | adopted. For example, in the case of the first and third embodiments, the ridges 6 and / or the liquid passage holes 4 may be arranged by a hound tooth check, respectively. It is also possible to arrange the ridge 6 and the liquid through hole 4 so that the liquid through hole 4 is necessarily located between the adjacent ridges 6. In the case of the second and fourth embodiments, the liquid through hole 4 formed in the groove portion 9 is arranged by a hound tooth check in plan view, but instead it is in the direction in which the groove portion 9 extends. The liquid passage hole 4 may be arranged at each intersection of the lattice formed by the straight line drawn and the straight line drawn in the direction perpendicular to this.

In each of the above embodiments, the upper nonwoven fabric 2 and the lower nonwoven fabric 3 can have the same dimensions, but instead of the upper layer nonwoven fabric 2, the dimensions of the lower nonwoven fabric 3 are longer than the upper nonwoven fabric 2 from an economical viewpoint. The lower layer nonwoven fabric 3 may be disposed only at the central portion in the longitudinal direction of the upper layer nonwoven fabric 2.

In addition, although the said embodiment is the example which applied the surface sheet of this invention to a sanitary napkin, this invention is equally applicable to absorbent articles other than that, for example, a panty liner, a secretion sheet, a incontinence pad, a disposable diaper, etc. .

The surface sheet of the present invention has a very high cushioning and softness by the upper nonwoven fabric and the lower nonwoven fabric formed in an arc shape, the first space formed therebetween, and the second space formed under the lower nonwoven fabric. This cushioning or soft feeling becomes more remarkable when the upper nonwoven fabric has a small convex portion. In addition, liquid backflow becomes less likely to occur due to the presence of the respective spaces. In addition, even if the arch shape of the upper layer nonwoven fabric is deformed by body pressure, the effect of the lower layer nonwoven fabric is less likely to affect the lower layer nonwoven fabric. Further, when the upper layer nonwoven fabric has a small convex portion, the arch shape of the upper layer nonwoven fabric is smaller than that of the lower layer nonwoven fabric, so that the contact area between the surface sheet and the skin becomes small, resulting in excellent freshness and smoothness.

Claims (10)

delete A surface sheet of an absorbent article composed of a laminated nonwoven fabric having an upper nonwoven fabric disposed on the skin side and a lower nonwoven fabric disposed on the absorbent side. The laminated nonwoven fabric is formed with a plurality of liquid through holes penetrating it, and the upper nonwoven fabric and the lower nonwoven fabric are joined to each other around the liquid through hole. Both the upper nonwoven fabric and the lower nonwoven fabric are raised arcuately toward the skin side between the liquid through holes, and a space is formed between the lower side of the lower nonwoven fabric and the upper nonwoven fabric and the lower nonwoven fabric, respectively. A plurality of ridges raised toward the surface sheet, The arcuate portion of the upper nonwoven fabric is a small convex portion smaller than the arcuate portion of the lower nonwoven fabric. delete 3. The surface sheet of an absorbent article as set forth in claim 2, wherein said upper nonwoven fabric is made of non-embossed nonwoven fabric, and said lower nonwoven fabric is made of embossed nonwoven fabric. 3. The surface sheet of an absorbent article as set forth in claim 2, wherein a plurality of ridges formed on the surface sheet are discretely arranged and form independent island shapes, respectively. 3. The surface sheet of an absorbent article as set forth in claim 2, wherein the plurality of raised portions formed in the surface sheet have a ridge shape in which their top portions are continuously lined up. The surface sheet of an absorbent article according to claim 2, wherein the convex tip of the small convex portion formed in the arcuate portion of the lower nonwoven fabric is in contact with the lower surface side of the upper nonwoven fabric. delete delete delete

Images