WO2003105738A1

WO2003105738A1 - Absorptive article

Info

Publication number: WO2003105738A1
Application number: PCT/JP2003/007345
Authority: WO
Inventors: 工藤　淳; 木下　正隆; 黒田　賢一郎
Original assignee: ユニ・チャーム株式会社
Priority date: 2002-06-14
Filing date: 2003-06-10
Publication date: 2003-12-24
Also published as: TWI263489B; KR20050012274A; CN1662202A; JP4495405B2; JP2004141619A; MY163482A; CN100482192C; TW200401628A; AU2003242200A1; KR100996476B1

Abstract

In a position spaced a predetermined distance on the right and left sides from a centerline (Oy-Oy) extending longitudinally of an absorptive article, a crimping section (9) where absorption layers (3, 4) together with a surface sheet (6) are compressed into a recess is formed to extend longitudinally continuously to define a central absorption region (11) between such crimping sections and an auxiliary absorption region (12) on the outer side of the crimping section, wherein in the central absorption region, a liquid guide layer (5) made of fibers joined together to leave voids in the interior and lower in density than the absorption layer is installed between the absorption layer and the surface sheet so as not to overlap the crimping section; thus, in the auxiliary absorption region, the absorption layer is covered with the surface sheet.

Description

Description Absorbent article Indication of related application

This application is based on Japanese Patent Application No. 2002-175127 filed on June 14, 2002, Japanese Patent Application No. 2002--253837 filed on August 30, 2002, March 2003. The application was filed claiming priority based on Japanese Patent Application No. 2003-95032 filed on March 31. The disclosure content of the above-mentioned Japanese patent application is incorporated as a part of the disclosure of this specification. Technical field

The present invention relates to an absorbent article suitable for absorbing menstrual blood and vaginal discharge excreted from female genital organs, and in particular, a liquid having a relatively high viscosity given to a surface sheet can be rapidly drawn into an absorbent layer. In addition, the present invention relates to an absorbent article capable of narrowing a diffusion range of a liquid. Background art

The general structure of an absorbent article that absorbs menstrual blood excreted from female genitals is that the surface of the absorbent layer is covered with a liquid-permeable top sheet. The surface sheet is formed of a non-woven fabric made of hydrophilic chemical fibers that have been subjected to hydrophilic treatment, or a hydrophilic fiber such as rayon. Nonwoven fabric is used.

In this absorbent article, a relatively high-density absorbent layer formed of hydrophilic fibers is located immediately below the topsheet. So give it to the surface of the surface sheet The obtained liquid is attracted by the hydrophilicity and the capillary action of the absorbing layer, and quickly penetrates the topsheet and is absorbed and held by the absorbing layer.

However, menstrual blood during menstruation has a relatively high viscosity and is continuously excreted, so that the liquid tends to saturate in the topsheet when the absorbent layer holds a certain amount of liquid. In other words, menstrual blood passes through the topsheet quickly due to its own weight, but the liquid permeation rate due to the capillary action of the absorbent layer is slightly slower than the liquid permeation rate through this topsheet. If a large amount of liquid is given in time, this large amount of liquid cannot be absorbed by the absorption layer, and the liquid tends to remain in the surface sheet. Since this liquid diffuses around the inside of the topsheet, a wide area of the topsheet is wetted by menstrual blood, which tends to give the wearer's skin a wet feeling. In addition, the spread of menstrual blood on the surface may increase the visual aversion to the wearer.

On the other hand, Japanese Patent Application Laid-Open No. 11-192592 describes that an absorbent layer formed of a mixture of flocculent pulp and a superabsorbent polymer is provided between a liquid-permeable surface sheet and a liquid-permeable surface sheet. An intervening second sheet with a lower density than the surface sheet has been disclosed. This second sheet is formed by bonding conjugate fibers subjected to hydrophilic treatment.

According to the invention described in this publication, the liquid applied to the topsheet is spot-absorbed by the second sheet and reaches the absorption layer, so that the bodily fluid does not easily stay on the topsheet and the second sheet. It is intended to be.

However, the liquid that has passed through the top sheet and reached the second sheet cannot be prevented from diffusing to the surroundings along the second sheet. In the absorbent article described in the above publication, since the area of the second sheet is not particularly limited, when the liquid is diffused along the second sheet, the liquid is easily diffused also in the topsheet.

In addition, those described in the above-mentioned publications are flat as a whole. -The liquid that has passed through the sheet and absorbed by the absorption layer will diffuse widely in the high-density absorption layer, and there will be a large amount of liquid in the absorption layer even in the outer peripheral region outside the second site. It is easy to be in a state. In this outer peripheral region, the surface sheet is in direct contact with the surface of the absorbing layer, and therefore, in the outer peripheral region, the surface sheet is easily saturated with the liquid at an early stage after the start of use. Therefore, the topsheet becomes wet in a wide range, so that the wearer's body is likely to be stuffy, and the liquid transmitted on the surface of the topsheet is likely to leak laterally.

Furthermore, in the process of manufacturing an absorbent article, a nonwoven fabric wound in the form of a raw material is generally used for forming a second sheet, and the nonwoven fabric is cut into a predetermined shape after being pulled out from the raw material. You.

However, in the case of a raw fabric, the bulk pressure (thickness) of the nonwoven fabric is crushed by the winding pressure, and the nonwoven fabric is stored in that state until use. Therefore, the bulk of the nonwoven fabric remains in a crushed state even after being pulled out from the web. In the second sheet manufactured from this non-woven cloth, the internal voids are crushed and the state becomes relatively high.

Therefore, the speed at which the liquid permeating the topsheet is drawn into the second sheet is reduced, and the liquid tends to stay on the topsheet. Furthermore, the liquid drawn into the second sheet travels through the relatively dense second sheet and diffuses to the surroundings before being absorbed by the absorbent layer, so that the liquid stays in the second sheet over a wide area. As a result, the liquid easily returns to the topsheet.

In addition, the bulky second sheet also has a problem with the soft feeling when worn. The present invention has been made in view of the above-mentioned conventional problems, and suppresses the diffusion range of a liquid on a surface sheet by rapidly absorbing a liquid repeatedly supplied within a limited area, and Liquid that reaches the outer region is always quick The aim is to provide an absorbent article that prevents side leakage by being absorbed into the product. Disclosure of the invention

The present invention provides a back sheet,

A liquid permeable surface sheet;

An absorbent layer having a hydrophilic material, provided between the back sheet and the liquid-permeable surface sheet; and providing an absorbent article comprising:

At a position separated by a predetermined distance on both the left and right sides from the longitudinally extending center line of the absorbent article, the absorbent layer is compressed together with the topsheet, and the crimped portion formed into a concave shape is formed so as to extend continuously in the longitudinal direction, A central absorption region between the crimping portions, an auxiliary absorption region outside the crimping portion,

In the central absorbent region, a liquid guide layer made of fibers joined so as to leave voids therein between the absorbent layer and the topsheet and having a lower density than the absorbent layer overlaps with the pressure-bonded portion. Therefore, in the auxiliary absorption region, the absorption layer is covered with the topsheet.

In the absorbent article of the present invention, the liquid given to the topsheet in the central absorbent region enters the space of the liquid guide layer having a low density by its own weight, and is absorbed by the liquid guide layer, and further absorbed in the liquid guide layer. The liquid is attracted to the hydrophilic action and the capillary action of the underlying absorbent layer, and is absorbed and held in the absorbent layer. Therefore, even when the liquid is repeatedly supplied to the central absorption region, the liquid is prevented from staying on the surface sheet due to the transfer of the liquid to the liquid guide layer, and the surface sheet is always in a state where the liquid easily permeates. Can be maintained. Further, since the liquid guide layer is provided only in a limited area in the central absorption area, the liquid repeatedly supplied mainly covers the limited area in the central absorption area. This allows the liquid to permeate, suppresses the diffusion of liquid on the topsheet, and enables spot absorption of liquid. In addition, the liquid that is absorbed by the absorption layer and attempts to diffuse to the side is blocked by the pressure-bonding portion, so that the liquid hardly reaches the auxiliary absorption region. Therefore, in the auxiliary absorption region, the surface sheet is less likely to be in a liquid-saturated state, and the liquid attached to the auxiliary absorption region is always drawn into the absorption layer located immediately below. As a result, the diffusion of the liquid on the topsheet can be kept within the central absorption region, making it difficult for the wearer's skin to feel moist, and maintaining the state where the auxiliary absorption region can always rapidly absorb the liquid. As a result, it is easy to prevent lateral leakage of liquid.

Preferably, the crimping portion further extends and is continuous with each other, surrounds a predetermined range as the central absorption region, the liquid guide layer has an area smaller than the central absorption region, and does not overlap with the crimping portion. It is.

When the central absorption region is completely surrounded by the crimping portion, the diffusion region of the liquid which is repeatedly supplied can be limited to the central absorption region.

Preferably, the absorption layer includes a lower absorber and an upper absorber overlaid on the lower absorber, wherein the upper absorber has a smaller area than the lower absorber and the central absorption region. The lower absorbent body and the upper absorbent body are compressed together with the top sheet in a concave shape,

The auxiliary absorption region has a thick portion adjacent to the pressure-bonded portion, where both the lower-layer absorber and the upper-layer absorber are present, and has a thin portion outside the thick portion. Here, the lower absorber is present but the upper absorber is not present.

In this structure, not only the central absorbent region but also the region just outside the crimping portion is bulky, so that the absorbent article comes into soft contact with the wearer's crotch. Also, if a large amount of liquid reaches the auxiliary absorption area beyond the crimping part Even so, this liquid can be quickly absorbed by the thick portion just outside the crimping section.

In the central absorption region, it is preferable that a plurality of liquid permeable holes penetrating the topsheet and extending to the liquid guide layer are formed. Further, it is preferable that the chemical fibers forming the topsheet and the chemical fibers forming the liquid guide layer are heat-sealed around the liquid passage holes.

If the liquid permeable holes are formed so as to penetrate the topsheet and extend to the liquid guide layer, the liquid given to the topsheet in the central absorption region easily permeates in the region where the liquid inner layer is provided.

To make matters to order such that the liquid applied repeatedly to quickly through the face sheet one preparative, fiber density of the dry the liquid guide layer is 0. 02 gZcm ³ or less 0. 005 gZcm ³ or more Is preferred.

The liquid guide layer, the fiber density of 0. 005 g / cm ³ ~ 0 when the given pressure in the wet state 9 80 P a (1 0 g / cm 2). 04 in within range of g / cm ³ Preferably, there is.

By heating after drawing the liquid guide layer out of the raw material, the bulk can be recovered and the density can be kept within the above range. When the density is within the above range, the porosity can be increased even when the inner layer of the liquid is subjected to a pressing force from the wearer's body, and the volume of the liquid guiding layer is restored when the pressing force is released. It's easy to do. The liquid that is repeatedly absorbed from the surface sheet can pass through the liquid guide layer by its own weight, and is held in the gap until it is absorbed by the absorption layer. Therefore, it is easy to prevent the liquid from diffusing in a wide range in the topsheet. Further, since the liquid guide layer functions as a cushion layer for relieving the contact pressure to the wearer's skin together with the surface sheet, the absorbent article has a soft feeling and can be worn comfortably.

The liquid guide layer does not include air through or air raid made of chemical fiber. Can be woven.

The liquid guide layer can be formed by folding the nonwoven fabric such that a plurality of the nonwoven fabrics are stacked.

When the liquid guide layer is formed by folding the nonwoven fabric in this way, the central absorbent region can be made bulky, and the central absorbent region can be softer and in contact with the excretory organ of the wearer.

The present invention is particularly suitable for a sanitary napkin of the type that is in close contact with the wearer's local area. In recent years, sanitary napkins that have a central part that is raised to adhere to the local area of women have increased. However, menstrual blood may spread on the surface even if the surface is brought into close contact with the vaginal opening for blood absorption. In this case, the part of the wearer's body other than the vaginal opening may be contaminated with menstrual blood, which may cause discomfort and trouble wiping menstrual blood. In the present invention, since the diffusion of the liquid on the napkin surface and the layer near the surface is very small, the wearer's body is hardly menstrual except for local areas. Accordingly, the present invention is excellent as a sanitary napkin of a local contact type having a raised center.

In other words, since menstrual blood can penetrate and be absorbed without diffusing from the vaginal opening, the wearer's body is hardly stained with menstrual blood except for local areas. This makes it harder to make the wearer uncomfortable, and makes it harder for the wearer to take the time to wipe out menstrual blood. In addition, because the diffusion area of menstrual blood on the surface is small, the wearer who wants to change the napkin may be concerned that menstrual blood may contaminate the body or that menstrual blood may leak out of the napkin. Hard to remember. BRIEF DESCRIPTION OF THE FIGURES

The present invention will be understood in more detail from the following detailed description and the accompanying drawings of preferred embodiments of the present invention, but they do not limit the present invention, but merely explain and explain the present invention. It is for. In the drawing,

FIG. 1 is a perspective view showing a sanitary napkin as an absorbent article according to a first embodiment of the present invention,

FIG. 2 is a plan view of the sanitary napkin shown in FIG. 1,

Fig. 3 is a cross-sectional view of the sanitary napkin shown in Figs. 1 and 2 taken along the lateral center line, Fig. 4A is an enlarged cross-sectional view of the central absorption region, Fig. 4B is an enlarged cross-sectional view of the auxiliary absorption region,

FIG. 5 is a cross-sectional view showing how the sanitary napkin is deformed during wearing, FIG. 6 is an enlarged plan view showing a pattern of liquid permeable holes,

FIG. 6 is a plan view showing a sanitary napkin according to a second embodiment of the present invention, FIG. 8 is a plan view showing a sanitary napkin according to a third embodiment of the present invention, and FIG. A plan view showing a sanitary napkin having a wing portion according to the embodiment,

FIG. 10 is a plan view showing a sanitary napkin according to a fifth embodiment of the present invention. FIG. 11 is a plan view showing a sanitary napkin according to a sixth embodiment of the present invention. 2B is a half cross-sectional view of a sanitary napkin provided with a leak-proof wall, FIG. 13 is an explanatory diagram of a method of manufacturing a sanitary napkin of the present invention,

FIG. 14 is an explanatory diagram showing another heating unit.

FIG. 15 is an explanatory diagram showing another heating unit.

FIG. 16 is an explanatory view showing another heating unit. BEST MODE FOR CARRYING OUT THE INVENTION

The present invention will be described in detail below with reference to the accompanying drawings. In the following description, numerous specific details are given for a thorough understanding of the present invention, but it will be obvious to one skilled in the art that the present invention may be practiced without these specific details. There will be. In other instances, well-known structures have not been shown in detail in order not to obscure the present invention unnecessarily.

FIG. 1 is a perspective view showing a sanitary napkin 1 as an absorbent article according to a first embodiment of the present invention with a surface in contact with a wearer's skin facing up, and FIG. 2 is a plan view of the sanitary napkin 1. Fig. 3 is a cross-sectional view of the sanitary napkin 1 shown in Fig. 1 taken along the center line Ox-Ox in the lateral direction, as viewed from the direction of arrows III-III. Figs. 4A and 4B are cross-sections of Fig. 3. FIG. 5 is an enlarged view of a different part of the figure, FIG. 5 is a cross-sectional view showing how the sanitary napkin 1 is deformed during wearing, and FIG. 6 is a view showing an arrangement pattern of liquid permeable holes formed in the topsheet. It is an enlarged plan view shown.

As shown in the plan view of Fig. 1, the sanitary napkin 1 is vertically long and has a right-hand side edge 1a and a left-hand side edge 1b that extend in a vertical direction, and an arc-shaped front edge 1c and a rear edge. The part has 1 d. As shown in FIG. 2, the sanitary napkin 1 has a left-right symmetric shape through a longitudinal centerline Oy—Oy, and a front-back symmetric shape through a horizontal centerline 0X—Ox.

As shown in the cross-sectional view of FIG. 3, the sanitary napkin 1 has a liquid-impermeable back sheet 2, an absorbent layer composed of a lower absorbent body 3 and an upper absorbent body 4, a liquid guide layer 5, and a liquid permeate. It has a structure in which a surface sheet 6 having a property is laminated.

The sanitary napkin 1 has a crimping portion 9 surrounding a predetermined area. As shown in FIG. 2, this crimping portion 9 has a constant width dimension Wa and extends continuously in a thin and long band shape. The crimping portion 9 includes a right crimping portion 9a and a left crimping portion 9b which extend in a vertical direction at a predetermined left and right distance from the vertical centerline Oy—0y, and a horizontal centerline 0X-Ox. It has a front crimping portion 9c and a rear crimping portion 9d that extend laterally at a position that is separated by a predetermined distance before and after. The right crimping section 9a and the left crimping section 9b and the front crimping section 9c and the rear crimping section 9d are continuous with each other, and the right crimping section 9a and the left The side crimps 9 b are curved towards the longitudinal center line O y— O y, and the front crimps 9 c and the rear crimps 9 d are away from the lateral center line O x— O x Carp.

In this embodiment, the crimping portion 9 has a symmetrical shape with respect to the longitudinal center line O y-0 y and a symmetrical shape with respect to the front and back via the lateral center line O x- O x. .

As shown in FIG. 2, the lower absorbent body 3 has a right edge 3a and a left edge 3b curved toward a longitudinal center line Oy—Oy, and a lateral center line Ox—Ox. It has a leading edge 3c and a trailing edge 3d that curve away from it. The upper absorber 4 includes a right edge 4a and a left edge 4b curved in the same manner as the right edge 3a and the left edge 3b, and a front edge 3c and a rear edge 3d. It has a front edge 4c and a rear edge 4d which are curved in the same manner as in FIG. When viewed from above, the upper absorbent core 4 has substantially the same peripheral edge as the outline 9 B of the outer periphery of the crimping portion 9.

The upper absorber 4 has an area larger than an area surrounded by a contour line 9B of the outer periphery of the crimping portion 9 and has an area smaller than that of the lower absorber 3. In this embodiment, both the lower absorber 3 and the upper absorber 4 are bilaterally symmetrical with respect to the longitudinal center line 0 y—0 y, and also with the lateral center line O x—O x. It has a symmetrical shape back and forth.

The lower absorber 3 and the upper absorber (ie, along the right crimp 9a, the left crimp 9b, the front crimp 9c and the rear crimp 9d) along the crimp 9 respectively. 4 and the topsheet 6 are pressed in a concave shape and are joined to each other at that portion.

The liquid guide layer 5 has a structure in which chemical fibers are bonded to each other to form a three-dimensionally extending skeleton such as an air-through nonwoven fabric as described later, and fine voids are formed between the fibers. Formed of low density nonwoven This nonwoven fabric is formed by folding two or more layers. In this embodiment, the nonwoven fabric is folded at two fold lines to form a three-ply structure.

When viewed from above, the liquid guide layer 5 made by folding the nonwoven fabric into three layers is rectangular, and has a width W1 between the side edge 5a and the side edge 5b extending in the vertical direction. The length between the laterally extending edge 5c and the edge 5d is designated by L1. As shown in FIG. 2, the area of the liquid guide layer 5 is sufficiently smaller than the area surrounded by the contour 9A inside the crimping portion 9, and the edges 5a, 5b, 5c Both 5d and 5d are located further inward than the crimping section 9 and do not engage the crimping section 9.

In this sanitary napkin 1, a region surrounded by a contour line 9A inside the crimping portion 9 is a central absorption region 11. In the central absorption region 11, the lower absorber 3 and the upper absorber 4 are stacked on the back sheet 2, and the liquid guide layer 5 that does not hang on the crimping section 9 is stacked, and the surface is Covered with sheet 6.

As shown in FIG. 1 and FIG. 4A, in the central absorption region 11, a large number of liquid permeable holes 15 are regularly arranged on the surface sheet 6. As shown in FIG. 4A, the liquid permeable holes 15 are formed so as to extend through the topsheet 6 and extend to the liquid guide layer 5. The surface sheet 6 and the liquid guide layer 5 both contain thermoplastic fibers, and the liquid permeable holes 15 are formed by inserting a heated pin. At this time, the thermoplastic fibers are fused, and the surface sheet 6 and the liquid guide layer 5 are bonded to each other at the liquid permeation hole 15. Therefore, it is not necessary to apply an adhesive to the boundary surface between the topsheet 6 and the liquid guide layer 5, otherwise, the permeation that allows the liquid to be introduced from the topsheet 6 to the liquid guide layer 5 is possible. O will reduce the area At the interface between the upper absorber 4 and the liquid guide layer 5, the upper absorber 4 and the liquid guide layer 5 are bonded by a hot-melt adhesive applied in a mesh, comb or spiral shape. . The upper and lower surfaces of the superposed upper absorber 4 and lower absorber 3 are covered with a hydrophilic tissue (not shown), and the interface between the upper absorber 4 and the lower absorber is No adhesive is present. The lower absorbent body 3 and the back sheet 2 are bonded with a hot melt adhesive applied to the boundary surface.

A region outside at least one of the lower absorber 3 and the upper absorber 4 outside the contour 9B outside the crimping portion 9 is an auxiliary absorption region 12. The auxiliary absorption region 12 has a thick portion 12a on the outer side of the contour 9B, in which an upper absorber 4 overlaid on a lower absorber 3 is covered with a surface sheet 6. Outside the thick portion 12a, the lower absorbent body 3 has a thin portion 12b covered with a surface sheet 6. Outside the auxiliary absorption region 12, the back sheet 2 and the front sheet 6 are bonded by a hot melt adhesive without interposing the lower absorber 3 and the upper absorber 4. .

As shown in FIGS. 1 and 2, the thick portion 12 a of the auxiliary absorption region 12 is formed so as to surround the crimp portion 9, and the thin portion 12 b is formed of the thick portion 1. It is formed to surround 2a.

Next, preferred materials for each component will be described.

As the surface sheet 6, an air-through nonwoven fabric in which chemical fibers are heat-sealed by hot air is preferably used. As the synthetic fiber, a core-sheath type composite synthetic fiber whose core is polyethylene terephthalate (PET) containing about 1.1% by mass of titanium oxide and whose sheath is polyethylene (PE) can be used. The core-sheath type composite synthetic fiber in which titanium oxide is added to the core has a good surface slipperiness and a good texture of the surface sheet 6. Surface sheet 6 The use of an air-through nonwoven fabric which is bulky and has voids between fibers provides good liquid permeability.

The core-sheath type composite synthetic fiber forming the surface sheet 6 is subjected to a hydrophilic treatment by adding a hydrophilic oil agent such as a surfactant before spinning or coating the hydrophilic oil agent after spinning. After spinning, it is preferable to mix with a water-repellent fiber made by coating a water-repellent oil agent. Mixing these water-repellent fibers has the effect of preventing liquid diffusion on the topsheet 6. When water-repellent fibers are mixed, it is preferable to form a large number of liquid permeable holes 15 in the surface sheet 6 as shown in FIG. 4A so that the liquid can easily pass through the surface sheet 6. . It is preferable that the water-repellent fiber is contained in an amount of 5 to 30% by mass relative to the surface sheet 6. When it exceeds 30%, the liquid is easily repelled excessively on the surface of the surface sheet 6, and the liquid permeability of the surface sheet 6 is reduced. If it is less than 5%, the effect of preventing liquid diffusion is reduced.

Further, the topsheet 6 may be a point-bonded nonwoven fabric or a spun-bonded nonwoven fabric made of chemical fibers, or a spun-lace nonwoven fabric containing hydrophilic fibers such as rayon and the water-repellent fibers. Alternatively, a resin film having a large number of liquid permeable holes, or a laminate of a resin film and a nonwoven fabric having a large number of liquid permeable holes may be formed.

In any case, the basis weight of the topsheet 6 is preferably in the range of 15 to 60 gZm ² . If it is less than the above, sufficient surface strength cannot be obtained, and there is a possibility that tearing may occur in a wet state. If it exceeds the above range, the topsheet 6 may be stiff and uncomfortable when worn. In order to promote the penetration of menstrual blood having a relatively high viscosity during menstruation, the density of the surface sheet 6 is preferably 0.12 g / cm ³ or less.

As shown in FIG. 4A and FIG. The hole dimensions Hd on the surface of the surface are 0.5 to 2.0 mm, the vertical arrangement pitch Hy is 2 to 5 mm, and the horizontal arrangement pitch Hx is 1 to 4 mm, and are arranged in a staggered manner. , Hy is longer than Hx.

The liquid guide layer 5 is made of a chemical fiber joined to a three-dimensional skeleton having a hydrophilic treatment by adding a surfactant before spinning or coating a surfactant after spinning, etc. Become. Since the liquid guide layer 5 is provided with a void, the liquid that has passed through the surface sheet 6 can easily enter the void by its own weight and be absorbed by the absorbent layer located thereunder. During this time, liquid can be retained in the void.

Examples of the liquid guide layer 5 having the above-mentioned structure include an air-through nonwoven fabric having a liquid-permeating function and an air-laid nonwoven fabric having a liquid-retaining function as well as a liquid-permeating function formed of hydrophilically treated chemical fibers. it can.

The air-through non-woven fabric has an eccentric core-sheath composite synthetic fiber (e.g., having a fineness of 4.4 dt ex and a fiber length of 5) having a core of polypropylene (PP) and a sheath of polyethylene (PE). Omm) can be used. Here, the sheath portions of the core-in-sheath type composite synthetic fibers are heat-sealed with hot air.

Alternatively, the air-through nonwoven fabric has a core-in-sheath composite fiber made of polyethylene terephthalate (PET) containing about 1.1% by mass of titanium oxide and a sheath of polyethylene (PE). A fiber layer having a fineness of, for example, 2.2 dt ex and a fiber length of 44 mm can be used. Here, the sheath portions of the core-sheath type composite synthetic fiber are heat-sealed with hot air.

Density of air-through nonwoven fabric which can be used as the liquid guide layer 5 is in the range of 0. 1 g / cm ³ at 0.0 05/0111 ³ or more, by heat-treating the air-through nonwoven fabric fed from raw, It is preferable to use the liquid guide layer 5 after recovering its bulk. For example, a heat treatment at 115 ° C to 300 ° C, preferably 130 ° C to 200 ° C (for example, for 1 minute with hot air at 135 ° C) to reduce the thickness of the non-woven fabric to 1 It can be increased 2 to 4 times.

It is preferable to cool the air-through non-woven fabric whose bulk has been recovered by heat treatment. This rapid cooling allows the bulk recovered by the heat treatment to be maintained as it is, and a low-density, cushioning air-through nonwoven fabric can be obtained.

The density of the air-through nonwoven fabric after bulk recovery is lower than that of the upper absorbent body 4 and the topsheet 6, and is preferably in the range of 0.005 gZcm ^{3 to} 0.02 cm ^{3 in} a dry state. If the density is less than the above range, the gap between the fibers becomes too small, so that the liquid permeates the topsheet 6 and hardly enters the gap by its own weight, and the liquid from the surface sheet 6 to the upper absorber 4 Probable function of menstrual blood worsens. On the other hand, if it exceeds the above range, the voids become too large, the strength of the skeleton extending in the three-dimensional direction of the fiber decreases, and the bulk tends to be collapsed by the contact pressure with the wearer's body.

Also, the air one-through nonwoven fabric after bulk recovery, density when given pressure in the wet state 980 P a (10 g / cm 2) ^{is, 0. 005 g / cm 3 ~0} . 04 g / cm 3 Is preferably within the range.

The thickness per one piece of the air-through-non-woven fabric after the bulk is recovered is 1.5 mn in the dry state and the wet state. ~ 3mm, preferably 2mn! ~ 3 mm. When a pressure of 980 Pa (10 g cm ² ) is applied in a wet state, the thickness is 0.5 mm to 2 mm, and preferably 0.5 mm to 1.5 mm. The thickness after the pressure is removed preferably recovers to 1.5 times or more the pressure, and more preferably 1.8 times or more. It is preferable to form the liquid guide layer 5 by laminating a plurality of the air-through nonwoven fabrics.

The thickness and density in the dry state and the wet state, and the wet state The measurement of the thickness and density when the pressure is applied is based on the measurement method described in (11) of the following (Example B).

In such a liquid guide layer, the gap can be maintained even if pressure from the wearer's body acts while the liquid is repeatedly supplied, and the liquid is guided and held in the liquid guide layer 5. The liquid can be prevented from returning to the topsheet 6. In addition, when the pressure from the wearer's body is reduced, the bulk can be immediately restored, and the function of permeating the liquid repeatedly supplied can be maintained for a long time.

Basis weight of the liquid guide layer 5 is preferably 1 5~3 0 O g / range der of m ² is, more preferably ^{2 0~1 0 0 g / m 2} . Within the above range, the liquid in the liquid guiding layer 5 can be transferred to the absorbing layer, and the liquid can be held in the voids in the liquid guiding layer 5 while the liquid is absorbed by the absorbing layer. . The air-laid nonwoven fabric used as the liquid guide layer 5 is formed by floating a mixture of hydrophilic fibers, such as natural fibers and regenerated cellulose fibers, and thermoplastic fibers, which are chemical fibers, in the air. After being collected and laminated, a heat treatment is performed to melt the surface of the thermoplastic resin fiber, and the thermoplastic resin fiber and the hydrophilic fiber are thermally welded. For example, as the hydrophilic fiber, wood pulp, rayon, acetate tray, natural cellulose fiber other than pulp, macerulized pulp, crosslink pulp and the like are used. As the chemical fiber, a core-sheath fiber (for example, having a fineness of 1.7 dtex and a fiber length of 13 mm) having a core portion of polypropylene (PP) and a sheath portion of polyethylene (PE) is used.

Further, the fibers may be bonded with a resin binder of emulsion emulsion.

This air-laid nonwoven fabric also has a three-dimensional skeletal structure in which chemical fibers are bonded to each other, or the hydrophilic fiber and the chemical fiber are joined to form voids between the fibers. Has formed. When this air-laid nonwoven fabric is used as the liquid guide layer 5, it has a liquid permeation function by allowing the liquid to enter the voids by its own weight, like the air-through nonwoven fabric. In addition, since the air-laid nonwoven fabric contains hydrophilic fibers such as natural fibers and regenerated cellulose fibers, the liquid that is to be retained in the surface sheet 6 can be drawn into the liquid guide layer 5 by the hydrophilic action. .

Even with this air-laid nonwoven fabric, after being pulled out from the raw material, the bulk is recovered by heat treatment at 100 to 300 ° C., preferably 130 to 200 ° C. for about 1 minute. Is preferred. When air-laid nonwoven fabric is used, the density when dry, the density when wet and pressurized, the thickness of one nonwoven fabric, the thickness when wet and pressurized, and the thickness when removed by pressure Preferred ranges such as a recovery rate and a basis weight are the same as those of the air-through-silver nonwoven fabric.

For the liquid guide layer 5, a nonwoven fabric obtained by treating a web by a production method such as a needle punch method or a high-mouth method, and then heat-treating the processed web to recover the bulk can be used. The liquid guide layer 5 is not limited to a nonwoven fabric, but may be a material having a three-dimensional skeleton and recovering its bulk by applying heat, such as urethane.

The sheet material such as the air-through nonwoven fabric and the air-laid nonwoven fabric for the liquid guide layer 5 may be heat-treated in its entirety to recover the bulk. The liquid guide layer 5 may leave a portion that does not restore the bulk. For example, when using the liquid guide layer 5 which is long in the longitudinal direction of the sanitary napkin 1, only the front part facing the vaginal opening is heat-treated to have a low density, and it is opposed to the groove in the rear anus and buttocks. The part may be in a higher density than the front part without restoring bulk. As a result, in the anterior portion facing the vaginal opening, menstrual blood given in a short time can be quickly transferred to the absorbent layer. On the other hand, in the high-density rear part, The obtained relatively small amount of liquid can be quickly drawn in. Or, conversely, only the rear part may be heat-treated to lower density without heat-treating the front part.o

The fineness of the fibers constituting the liquid guide layer 5 may be 1.8 to 33 dtex, but the bulk recovery is good when the pressure from the wearer's body is released, and the liquid returns. The fineness is preferably 2.4 to 11 dtex in order to make the phenomenon (ゥ et back phenomenon) less likely to occur.

In this embodiment, the liquid guide layer 5 is formed by folding the nonwoven fabric into three layers. Here, in the nonwoven fabric manufactured so as to have the same basis weight as the liquid guide layer 5 without being folded, as the fiber density increases, the thickness also decreases, and the voids inside the nonwoven fabric decrease. Therefore, in such a nonwoven fabric, the function of guiding the liquid as described above into the gap by its own weight is reduced. Further, as shown in FIG. 3, in this embodiment, two fold lines where the three nonwoven fabrics are folded are directed in the longitudinal direction of the sanitary napkin 1, and the side edges 5a and the side of the liquid guide layer 5 are formed. Positioned to match edge 5b. When folded in this way, the liquid guide layer 5 is easily deformed so that the central absorption region 11 having the liquid guide layer 5 is kept in close contact with the vaginal opening.

The number of layers obtained by folding the nonwoven fabric in the liquid guide layer 5 is not necessarily limited to three layers, but may be two layers, four layers or more. Since the liquid enters the gaps between the layers of the folded nonwoven fabric, the larger the number of layers, the more the liquid can be guided to the liquid guide layer 5. However, when the number of times of folding is too large, the process of forming the liquid guide layer 5 becomes complicated, and the productivity is reduced. If too many gaps are created due to an excessive number of layers, the liquid may stagnate in that portion.

Therefore, the number of nonwoven fabrics to be stacked is preferably about two to five, in view of the liquid guiding function and the production efficiency. Suitable for liquid guide layer 5 The most preferred stack is three stacks to provide deformability and an appropriate number of voids.

The liquid guide layer 5 may be formed by cutting out strips having a size of Wl × L1 from the nonwoven fabric and, for example, stacking three strips. The thus laminated one can function similarly to the above-mentioned folded non-woven fabric in terms of deformability. However, in order to prevent the liquid guide layer 5 from overlapping the crimping portion 9, the width W1 of each strip must be very small. Such a thin strip is difficult to handle in the manufacturing process of the sanitary napkin 1. Therefore, it is desirable that the nonwoven fabric is folded to have a size of W1 × L1, and the liquid guide layer 5 is formed.

The upper absorbent body 4 is formed of a pulp laminate such as pulverized pulp, mercerized pulp, or cross-linked pulp, and has a basis weight of, for example, 230 g / m ² . As the lower absorbent body 3, a laminate of the pulp containing 1.5 to 2.0% by mass of a high absorbent polymer can be used. The basis weight and thickness of the lower absorber 3 are not more than 80% of the upper absorber 4. For example, the basis weight of the lower absorber 3 is 160 g / m ² . The upper absorber 4 and the lower absorber 3 are overlapped, and the upper and lower surfaces thereof are covered with a tissue (not shown). The lower absorber 3 is embossed in a lattice pattern as shown in FIG.

The density of the upper absorber 4 and the lower absorber 3 is preferably in the range of 0.1 to 0.6 / cm ³ . If it is less than the above range, the rigidity of the sanitary napkin 1 becomes too low, and wrinkles and breaks may occur during mounting. In addition, when it exceeds the above range, the rigidity of the sanitary napkin 1 becomes too high, and it is easy to give a discomfort to the wearer's body. However, the lower layer absorber 3 has a higher density than the upper layer absorber 4 in the above range of the density due to the formation of the lattice pattern embossment in the lower layer absorber 3 as described above. Further, in order to make it easier for the liquid guided to the liquid guide layer 5 to be sucked into the upper absorber 4, the density of the upper absorber 4 should be at least twice the density of the liquid guide layer 5. Preferably, it is more preferably 5 times or more.

The back sheet 2 is a liquid-impermeable and air-permeable sheet, such as a polyethylene (PE) film or a polypropylene (PP) film having fine air holes formed therein. For example, by stretching by mixing _{C a C 0 3, B a} S 0 inorganic filler one such ₄ to the resin, fine vents off Irumu is formed properly dispersed, the breathability improves. The film has a thickness of about 15 to 50 m. Alternatively, a material obtained by laminating a thermoplastic resin on a nonwoven fabric may be used.

As shown in FIG. 3, a pressure-sensitive adhesive layer Ί is applied on the outer surface of the back sheet 2 in a strip shape so as to extend continuously in the longitudinal direction of the sanitary napkin 1 with a predetermined width. ing. Before use, the pressure-sensitive adhesive layer 7 is covered and protected by a release sheet (not shown).

The crimping section 9 is formed by embossing using a heating roller. More specifically, a flat roll is applied to the lower surface of the lower absorbent body 3 in a state where the lower absorbent body 3, the upper absorbent body 4, and the surface sheet 6 are stacked, and the upper surface of the surface sheet 6 is A heating roll having a convex portion of the emboss pattern is applied, and the lower absorbent member 3, the upper absorbent member 4, and the surface sheet 6 are pressed against the convex portion and heated. As a result, the fused portion 9D of the thermoplastic resin contained in the surface sheet 6 that has melted and solidified into a film shape is not fused between adjacent fused portions 9D as shown in Fig. 2. The crimping section 9 is provided intermittently so as to leave the section 9E. In the non-fused portion 9E as well as the fused portion 9D, the absorbent layer is strongly compressed, and has a higher density than the region other than the crimped portion 9.

After the crimping section 9 is formed in this manner, the lower side of the lower absorbent body 3 The back sheet 2 is attached to.

In this embodiment, the fusion portion 9D is formed in a linear shape inclined in both the longitudinal direction and the lateral direction of the sanitary napkin 1. The width dimension of the fusion portion 9D is, for example, 0.2 to 1.5 mm, and the pitch P of the fusion portion 9D is, for example, 1 to 5 mm. The width W a of the crimping portion 9 is about 2 to 4 mm.

As described above, in order to properly form the fused portion 9D and the non-fused portion 9E, the temperature of the heating roll is set to 120 ° C or more, and the pressure between the rolls is set to 980 to 2 It is preferable to set within the range of 45 OP a. When the crimping portion is formed at the above-mentioned temperature and pressure, the right crimping portion of the crimping portion 9 is attached to the wearer's body together with the underwear and receives pressure from the thighs from both sides as shown in FIG. The sanitary napkin 1 can be easily bent at the portion 9a and the left crimp portion 9b. In addition, problems such as breakage at the fused portion 9D due to excessively high embossing pressure do not occur.

Further, as described above, in the central absorption region 11, each edge of the liquid guide layer 5 is located inside the press-fit portion 9, so that the liquid guide layer 5 does not hang on the crimp portion 9. If the liquid guide layer 5 hangs on the crimping portion 9, the nonwoven fabric forming the liquid guide layer 5 is bulky and has a three-dimensional skeleton formed by fibers, so that the adhesive strength between the layers in the crimping portion 9 Will decrease. In this case, the surface sheet 6 and the upper absorbent body 4 are not fixed or weakly fixed in the crimping section 9, and are given to the central absorbent area 11, and are applied to the surface sheet 6 or the upper absorbent body 4. Diffusing menstrual blood cannot be effectively prevented by the crimping section 9.

In addition, if the bonding strength at the crimping portion 9 is weak, the central absorbent region 11 is deformed and it is difficult to protrude toward the wearer's crotch portion. Misalignment and break into topsheet 6 and liquid guide layer 5 Is more likely to occur. As a result, it becomes difficult to make the central absorption region 11 adhere to the vaginal opening, and it is impossible to achieve one of the initial objectives of spot absorption of liquid in the central absorption region 11.

On the other hand, if the crimping portion 9 is formed so as not to be hung on the liquid guide layer 5, the central absorption region 11 can be easily deformed and protrude toward the crotch of the wearer, and the central absorption region 11 can be placed at the vaginal opening. It becomes possible to adhere to the software. Further, the crimping portion 9 can effectively prevent the diffusion of the liquid.

Hereinafter, preferred dimensions of each component will be described. The treatment napkin 1 according to the first embodiment has a normal size used in the daytime or the like, and has a width dimension of 80 mm at the horizontal center line O x—O x and a vertical center line 0 y—0. The length dimension in y is about 210 mm.

The central absorbent area 11 surrounded by the crimping section 9 needs to have a sufficient area to be in close contact with the female vaginal opening, and the width dimension W2 is in the range of 25 mm to 50 mm. The longitudinal dimension L2 is in the range of 50 to 110 mm. Further, in the long evening eve suitable for wearing at night shown in FIG. 8, it is preferable that the central absorption region 11 extends rearward and extends beyond the anus of the wearer. The upper limit of the vertical dimension of the region 11 is about 280 mm.

The width dimension W 1 and the vertical dimension L 1 of the liquid guide layer 5 are set according to the area of the central absorption region 11, but the edge portion of the liquid guide layer 5 and the inside of the crimping portion 9 are set. It is necessary to leave a certain distance between the contour and 9A. For example, the distance between the edge of the liquid guide layer 5 and the contour 9A, that is, (W 2 −W 1) No 2 and (L 2 −L 1) Z 2 is 1 to 10 mm. The range is preferably, and more preferably, 2 to 6 mm. Within the above range, there is no risk of the liquid guide layer 5 being caught when the crimping portion 9 is formed. The width of the upper absorber 4 in the above embodiment at the horizontal center line O x — 0 X is about 55 mm, and the length at the vertical center line 0 y — 0 y is 120 mm. It is about. The lower absorber 3 has a width of about 75 mm at the horizontal center line O x — 0 X and a length of about 180 mm at the vertical center line 0 y — 0 y. The width Wb of the thick portion 12a in the auxiliary absorption region shown in FIG. 3 is preferably about 3 to 1 Omm.

When using the sanitary napkin 1, first, the release sheet protecting the pressure-sensitive adhesive layer 7 is peeled off, and the inside of the undergarment mouthpiece 20 is passed through the pressure-sensitive adhesive layer 7. Glue the sanitary napkin 1 to the.

In a state where the sanitary napkin 1 is attached to the wearer's body together with the underwear, the crotch portion 20 and the sanitary napkin 1 receive the tightening force of the thigh from both sides. In the sanitary napkin 1, the right crimping portion 9a and the left crimping portion 9b extending in the vertical direction are formed symmetrically in the horizontal direction with respect to the vertical center line 0y-0y. When a force is applied, the portion of the right crimping portion 9a and the portion of the left crimping portion 9b of the sanitary napkin 1 function as a hinge, and the sanitary napkin 1 uses the hinge portion as shown in FIG. Bendable.

In particular, the liquid guide layer 5 provided in the central absorption area 11 does not extend over the crimping section 9, and the crimping section 9 places a lower absorbent body between the back sheet 2 and the front sheet 6. Only 3 and the upper absorber 4 are present. Therefore, the rigidity difference and the thickness difference between the crimp portion 9 and the other region can be considerably increased, and the sanitary napkin 1 is folded at the positions of the right crimp portion 9a and the left crimp portion 9b. It becomes easy to bend.

At this time, the tightening force acting on the right crimping portion 9a and the left crimping portion 9b from the thigh affects the central absorbing region 11. Due to this tightening force, the upper surface of the central absorbent area 11 protrudes toward the wearer's crotch, and In the collecting area 11, the topsheet 6 easily adheres to the vaginal opening. At this time, the central absorption region 11 is bulky, having not only the lower absorber 3 and the upper absorber 4 but also the liquid guide layer 5, and the liquid guide layer 5 is a low-density material. It can adhere to the vaginal opening softly.

Relatively viscous liquid such as menstrual blood excreted from the vaginal opening is mainly given to the topsheet 6 in the central absorption area 11, and this liquid passes through the topsheet 6 to the liquid guide layer 5. Given. That is, the liquid guide layer 5 has a structure in which chemical fibers are bonded and has a skeleton extending in a three-dimensional direction and a void is formed, so that the liquid that has passed through the surface sheet 6 by its own weight is provided. Is guided into the space of the liquid guide layer 5. Further, the liquid absorbed in the liquid guide layer 5 in this way is sucked by the hydrophilic action and the capillary action of the high-density upper absorbent body 4 located thereunder, and is absorbed by the upper absorbent body 4. Will be retained. Further, the liquid absorbed by the upper absorber 4 is absorbed and held by the lower absorber 3 thereunder.

The liquid guide layer 5 has a high ability to transfer the liquid downward, and the liquid is held in the liquid guide layer 5 until it is sucked by the upper absorber 4, so that the top sheet 6 is saturated with the liquid. Hard to do. Therefore, the topsheet 6 is unlikely to give a wet feeling during wearing.

When the pressing force due to the weight of the wearer acts on the sanitary napkin 1 in a sitting posture or the like, the pressing force is received by the topsheet 6 and the liquid guide layer 5. The liquid guide layer 5 made of a low-density sheet whose bulk has been recovered by heat treatment can also function as a cushion layer. In addition, since the porosity can be maintained high even when the liquid guide layer 5 is compressed by a pressing force applied from the wearer's body, the liquid provided from the surface sheet 6 is temporarily held. Thus, the function of sucking into the upper absorber 4 can be maintained for a long time. When the pressing force from the wearer's body is released, the liquid guide Layer 5 can recover the bulk effectively.

The water-repellent fibers contained in the topsheet 6 function to prevent liquid from diffusing. However, since the surface sheet 6 can surely maintain its bulk and leave voids formed inside, the liquid permeation function of the surface sheet 6 is hardly impaired even if the water-repellent fibers are included. .

In this embodiment, as shown in FIG. 4A, a large number of liquid permeable holes 15 are formed so as to penetrate the top sheet 6 and extend to the liquid guide layer 5, so that the surface of the top sheet 6 is provided. The liquid thus permeated passes through the liquid permeation hole 15 and is provided to the liquid guide layer 5. Therefore, the liquid applied to the topsheet 6 easily falls under its own weight to the liquid guide layer 5, whereby the remaining of the liquid and the diffusion of the liquid on the topsheet 6 are further easily prevented.

As described above, in the sanitary napkin 1, the liquid repeatedly and intensively applied to the central portion of the central absorption region 11 is transmitted to the liquid guide layer 5 through the topsheet 6, and is applied to the topsheet 6. The liquid is difficult to diffuse. Further, since the liquid guide layer 5 has a low density, the diffusion of the liquid in the liquid guide layer 5 to the surroundings is suppressed, which also suppresses the liquid diffusion in the topsheet 6. it can.

The liquid that has passed through the surface sheet 6 and the liquid guide layer 5 is absorbed and diffused by the upper absorber 4, and further absorbed and diffused by the lower absorber 3. However, since the distance between the upper absorbent body 4 and the topsheet 6 is large in the central absorbent area 11, the color of menstrual blood diffused in the upper absorbent body 4 It is difficult to see from the side. As described above, since the diffusion of the liquid on the topsheet 6 is limited, and the liquid diffused by the upper absorbent body 4 is not visible from the side of the topsheet 6, the wearer who looks at the surface of the sanitary napkin 1 in use is used. However, it is difficult to remember discomfort.

The liquid given to the central absorption region 1 1 is composed of the upper absorber 4 and the lower absorber 3 When diffused into the surroundings, the crimping portion 9 functions to prevent diffusion of the liquid. That is, the liquid that has spread through the upper absorbent core 4 and the lower absorbent core 3 and spreads in the lateral direction of the sanitary napkin 1 and reaches the right crimping portion 9a and the left crimping portion 9b concentrates on the non-fusion portion 9E. Then, it is transmitted to the adjacent non-fusion part 9E, and moves in the longitudinal direction of the sanitary napkin 1 along the right crimping part 9a and the left crimping part 9b. Therefore, the liquid supplied to the central absorption region 11 becomes difficult to be transmitted to the auxiliary absorption region 12 around the pressure bonding portion 9. In the auxiliary absorption region 12 outside the central absorption region 11, as shown in FIG. 4B, a thick portion 12a is provided immediately outside the crimping portion 9 and outside. In the deformed state as shown in FIG. 5, the thick portion 12a fits and fits to the outer crotch portion of the labia majora. Further, as shown in FIG. 5, the crimping portions 9 are both buried between the bulky central absorption region 11 and the thick portion 12a, so that the crimping portion 9 having high density and high rigidity is No direct contact with body. Therefore, the crimping portion 9 does not give a rigid feeling to the wearer's body.

When menstrual blood transmitted through the crotch adheres to the auxiliary absorption area 12, or when menstrual blood transmitted along the surface of the central absorption area 11 reaches the auxiliary absorption area 12 beyond the crimping section 9, the liquid is the absorption of liquid by capillary action of the upper layer absorbent body 4 located just below the surface one DOO 6, quickly becomes transmitted through the surface sheet one bets 6 to be absorbed in the upper layer absorbent body 4 _O As described above, the liquid absorbed by the upper absorbent body 4 and the lower absorbent body 3 in the central absorbent area 11 1 is hardly transmitted to the auxiliary absorbent area 12 beyond the pressure bonding portion 9, so that the auxiliary absorbent area In 12, the upper absorber 4 and the lower absorber 3 are less likely to be saturated with a large amount of liquid. In addition, the absorption power of the lower absorber 3 and the upper absorber 4 is not so small even in the auxiliary absorption region 12. As a result, the liquid adhering to the topsheet 6 in the auxiliary absorption area 12 is immediately absorbed by the absorption layer therebelow, preventing side leakage of the liquid. Cheap.

In the auxiliary absorption region 12, the high-density upper absorbent body 4 is located immediately below the topsheet 6, and the liquid adhering to the surface sheet 6 by the hydrophilicity of the upper absorbent body 4 and the capillary action is quickly discharged. In the auxiliary absorption region 12, it is not necessary to provide a liquid permeable hole in the topsheet. However, a liquid permeable hole may be formed in the surface sheet 6 in the auxiliary absorption region 12.

The lower absorbent body 3 is provided in a wide range from the central absorbent area 11 to the auxiliary absorbent area 12. Although the lower absorbent body 3 has a small basis weight and thickness, it has a high absorbent polymer inside. Therefore, the lower absorbent body 3 has a large liquid holding capacity. Therefore, in the central absorption region 11 and the auxiliary absorption region 12, a large amount of liquid can be held in the lower absorbent body 3, and the sanitary napkin 1 as a whole has a large liquid absorption capacity. As described above, in the sanitary napkin 1, the central absorption region 11, which is defined by the crimping portion 9 and mainly receives the liquid, is tightly adhered to the vaginal opening. In the central absorption region 11, the topsheet 6 is unlikely to be saturated with the repeated supply of the liquid, and the liquid is not easily diffused. Even if the liquid supplied to the central absorption area 11 reaches the auxiliary absorption area 12 beyond the crimping section 9, the liquid can be immediately absorbed in the auxiliary absorption area 12.

7 to 11 show another embodiment of the present invention. In these embodiments, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

FIG. 5 is a plan view showing a sanitary napkin 1A as an absorbent article according to a second embodiment of the present invention.

This sanitary napkin 1A has the shape of the crimping portion 9 and the length of the liquid guide layer 5. Only the configuration is different, and all other configurations and dimensions are the same as those of the treatment napkin 1 shown in FIGS.

In the sanitary napkin 1A shown in FIG. 7, the crimping portion is formed only of the right crimping portion 9a and the left crimping portion 9b, and the front crimping portion 9c and the rear crimping portion of the sanitary napkin 1 shown in FIG. Part 9d is not formed. The right crimping portion 9a and the left crimping portion 9b are formed similarly to the sanitary napkin 1 shown in FIGS.

This sanitary napkin 1A also has a right crimping section 9a and a left crimping section 9b that extend vertically on the left and right sides, so the deformation state when worn on the crotch of the wearer is shown in FIG. It will be the same. In this sanitary napkin 1A, a central absorbent area 11A is provided between the right-side crimping section 9a and the left-side crimping section 9b, and auxiliary absorption is provided on the right and left outer sides of the right-side crimping section 9a and the left-side crimping section 9b. An area 12 A is provided. The liquid guiding function and the absorbing function in the central absorption region 11 A and the auxiliary absorption region 12 A are the same as the central absorption region 11 and the auxiliary absorption region 12 of the sanitary napkin 1.

The sanitary napkin 1A also has a symmetrical shape via the longitudinal centerline Oy-Oy, and has a symmetrical shape back and forth via the transverse centerline Ox-Ox. The length Lb from the lateral center line O x—O x to the front ends of the right crimping portion 9 a and the left crimping portion 9 b is defined as the front edge of the liquid guide layer 5 from the lateral center line. The length up to the part 5c is longer than the length La. Similarly, the length from the horizontal center line O x — O x to the rear end of the right crimping portion 9 a and the rear end of the left crimping portion 9 b is the rear end of the liquid guide layer 5 from the horizontal center line. It is longer than the length dimension up to 5 d.

And it is preferable that Lb-La is 3 mm or more, more preferably 5 mm or more.

In the sanitary napkin 1 A thus configured, the central absorption region 11 A When menstrual blood given to the central part and absorbed from the top sheet 6 via the liquid guide layer 5 into the upper absorber 4 and the lower absorber 3 diffuses the absorbers 3 and 4 to both sides, The diffusion can be prevented by the right crimping portion 9a and the left crimping portion 9b, and the absorbers 3, 4 located in the auxiliary absorption region 12A are less likely to be saturated with the liquid.

FIG. 8 is a plan view showing sanitary napkin 1B as an absorbent article according to the third embodiment of the present invention.

The sanitary napkin 1B has the same basic structure as the sanitary napkins 1 and 1A, but differs only in the overall size and the shape of the crimping portion.

The length of the sanitary napkin 1B in the longitudinal direction is larger than each of the sanitary napkins 1 and 1A. The sanitary napkin 1B has a wide rear portion, which adheres to the wearer's buttocks during wear, and is generally referred to as a "hib guard portion".

The sanitary napkin 1B has a back sheet, a lower absorbent body 3A, an upper absorbent body 4A, a liquid guide layer 5A, and a top sheet 6A. And greater than 1A. The sanitary napkin 1B has a crimp portion 90 that is stretched in the longitudinal direction. The crimping portion 90 includes a right-side crimping portion 90a, a left-side crimping portion 90b, a front crimping portion 90c, and a rear crimping portion 90d which are continuously formed so as to surround the central absorption region 11B. have. The crimping section 90 further includes a pair of crimping sections 90 e and 90 f extending forward from the front crimping section 90 c, and a pair of crimping sections 90 a, 90 a, and a left side crimping section 90 b inward. 90 g and 90 h. The front extension crimping portions 90e and 90f are inclined so that the distance between them increases toward the front end. The front ends of the forward extension crimps 90e, 90f are located away from the edge of the sanitary napkin. As shown in FIG. 8, each part of the crimp portion 90 has a predetermined width. However, in this crimped portion 90, similarly to the embodiment shown in FIG. 2, film-shaped fused portions 9D and non-fused portions 9E are formed alternately along the extending direction of the crimped portion.

Further, the liquid guide layer 5A is provided so as not to be applied to the pressed portion 90 in the central absorption region 11B. An auxiliary absorption region 12B is formed outside the crimp portion 90.

In this sanitary napkin 1B, the central absorbent region 11B is considerably long in the vertical direction, so that the central absorbent region 11B can fit the wearer's body from the vaginal opening to the buttocks. . Here, since the sanitary napkin is easily bent at the portions of the front extension crimping portions 90 ° and 90f, the sanitary napkin fits near the muzzle in front of the vaginal opening.

In addition, since the central absorbent area 11B is easily bent starting from the inner crimped portions 90h and 90g, the front area of the central absorbent area 11B fits into the vaginal opening, and the rear area is the buttocks. Fits in the groove.

Then, the menstrual blood given to the surface sheet 6A can be guided to the upper absorber 4A and the lower absorber 3A by the liquid guide layer 5A located in the central absorption region 11B. Menstrual blood given to the absorption region 11B is unlikely to be brought to the auxiliary absorption region 12B beyond the crimping portion 90 due to diffusion along the surface sheet 6A. Therefore, even if the length of the back portion of the sanitary napkin 1B, that is, the length of the hip guide portion in the vertical direction or the width in the horizontal direction is relatively small or thin, leakage of menstrual blood in the buttocks direction is prevented. It becomes easier to prevent.

Although the liquid guide layer 5A is quite vertically long, the right crimp section 90a, the left crimp section 90b, the front crimp section 90c and the rear crimp section 90d, and the front extension crimp section 90e, 90 f, more preferably 90 g, 9 Oh It is provided so as not to be hung on. Therefore, each of the crimping portions can be formed in a substantially uniform compressed state, and the entire sanitary napkin 1B is easily deformed so as to fit the wearer's body. In particular, when the liquid guide layer 5A is arranged so as not to be hung on the inner press-fitted portions 90g and 90h, the inner press-fitted portions 90g and 90h can be formed in a substantially uniform compressed state, and the central absorbent region 11B It becomes easy to bend from the inside crimped portions 90 g and 90 h as starting points.

Conversely, the liquid guide layer 5A may hang over the inner press-bonded portions 90 g and 90 h. For example, when the thickness of the liquid guide layer 5A is large or made of a material having high bending rigidity, the liquid guide layer 5A is compressed by the inner crimping portion 90 g, 9 Oh to form the liquid guide layer 5A. The central absorbent region 11B having A can be easily bent as described above, starting from the inner crimped portion 90 g, 9 Oh.

In the embodiment of FIG. 8, the front extension crimping portions 90 e and 90 f and the inner crimping portions 90 g and 90 h may not be particularly provided.

Each of the sanitary napkins 1, 1 A, and 1 B has a shape without wings on both side edges, but has wing portions projecting laterally from both side edges in the sanitary napkin. It may be something.

FIG. 9 shows a fourth embodiment in which the wing portion is formed based on the structure of the sanitary napkin 1 shown in FIGS. 1 and 2 as an example. FIG. 9 shows a sanitary napkin 1C provided with a pair of wing portions 21 and 21 extending along the lateral center line Ox-Ox. In this treatment napkin 1C, the back sheet 2 has two projections corresponding to the wings 21 and 21, but the topsheet 6 does not have such projections. The right edge 6a and the left edge 6b extend along the bases of the wings 21 and 21. On both left and right sides, liquid-impermeable sheets 22, 22 formed of a hydrophobic nonwoven fabric or a water-repellent nonwoven fabric are displayed on the top. Appearing on the surface. The inner edges 22 a, 22 a of the sheets 22, 22 are located at a fixed distance from the longitudinal center line 0 y—O y and the outer contour 9 of the crimping section 9. Surface sheet 6 is exposed in the area outside of B and sandwiched between edges 22a and 22a.

The sheets 22 and 22 are adhered to the top sheet 6 inside the edges 6a and 6b, and are adhered to the back sheet 2 at the wings 21 and 21. That is, the wing portions 21 and 21 are formed by bonding the back sheet 2 and the sheet 22 to each other, so that liquid cannot penetrate into this portion.

In the sanitary napkin 1C, the liquid-impermeable sheets 22 and 22 are provided on both outer sides of the auxiliary absorption region 12 so that lateral leakage such as menstrual blood can be further prevented. Become. Further, by attaching the wings 21 and 21 to the outer surface of the crotch portion of the underwear via the pressure-sensitive adhesive layer, the sanitary napkin 1C can be firmly fixed at the crotch portion.

Further, since menstrual blood is unlikely to diffuse from the central absorption region 11 having the liquid guide layer 5 to the periphery beyond the crimping portion 9, the sheets 22 and 22 do not need to have high water repellency. Therefore, high water repellency is not required for the wing portions 21 and 21. Sheets 22 and 22 do not require a large basis weight. Even if the wings 21 and 21 have a small basis weight, the fear of side leakage does not increase. FIG. 10 is a plan view showing a sanitary napkin 1D which is an absorbent article according to a fifth embodiment of the present invention.

This sanitary napkin 1D has a crimping portion 190, and this shape is different from the above-described embodiments, but the other basic structure of the sanitary napkin is shown in FIG. This is substantially the same as the first embodiment shown.

The crimping section 190 has a central absorption area 1 similar to the crimping section 9 shown in FIG. In addition to the right crimp section 9a, left crimp section 9b, front crimp section 9c, and rear crimp section 9d that surround 1, the front extension crimp sections 9e, 9f and the rear extension crimp section 9g , 9 h. The liquid guide layer 5 is provided in the central absorption region 11.

The front extension crimping portion 9e extends further forward from the boundary between the right crimping portion 9a and the front crimping portion 9c, and the front extension crimping portion 9f includes the left crimping portion 9b and the front crimping portion 9c. It extends further forward from the boundary with c. Here, the front extension crimping portion 9e can be regarded as an extension of the right crimping portion 9a, and the front extension crimping portion 9f can also be regarded as an extension of the left crimping portion 9b. The forward extension crimp 9e and the front extension crimp 9: f are inclined away from the vertical centerline 0y—0y toward the front edge 1c of the sanitary napkin. The front ends of the extension crimping portion 9e and the front extension crimping portion 9f are located away from the front edge 1c, the right edge 1a, and the left edge 1b.

The rear extension crimping section 9 g extends further rearward from the boundary between the right side crimping section 9 a and the rear crimping section 9 d, and the rear extension crimping section 9 h includes the left side crimping section 9 b and the rear crimping section 9. It extends further back from the boundary with d. Here, the rear extension crimping portion 9g can be regarded as an extension of the right crimping portion 9a, and the rear extension crimping portion 9h can also be regarded as an extension of the left crimping portion 9b. The rear extension crimping section 9 g and the rear extension crimping section 9 h are inclined away from the longitudinal center line O y— O y toward the rear end 1 d of the sanitary napkin. The rear ends of the extension crimping portion 9 g and the rear extension crimping portion 9 h are located away from the rear edge 1 d, the right edge 1 a and the left edge 1 b.

FIG. 11 is a plan view showing a sanitary napkin 1E according to a sixth embodiment of the present invention. The sanitary napkin 1E is the sanitary napkin 1C shown in FIG. It has almost the same basic structure. More specifically, the sanitary napkin 1E has wing portions 21 and 21 and sheets 22 and 22 on both left and right sides.

A crimping portion 190 is formed in a region sandwiched between the edges 22a and 22a of both sheets 22 and 22 in the same manner as the sanitary napkin 1D shown in FIG. .

In the sanitary napkins 1D and 1E, the central absorbent region 11 surrounded by the right crimp portion 9a, the left crimp portion 9b, the front crimp portion 9c, and the rear crimp portion 9d, that is, the liquid guide layer 5 The provided area is deformed convexly toward the wearer as shown in FIG. 5, and the central absorption area 11 is easily brought into close contact with the excretory organ of the wearer.

In a region ahead of the front crimping portion 9c, the front extension crimping portion 9e 'and the front extension crimping portion 9f are formed so as to move away from each other toward the front edge 1c. Therefore, the region sandwiched between the front extension crimping portion 9 e and the right side edge 1 a and the region sandwiched between the front extension crimping portion 9 f and the left side edge 1 b correspond to the front extension crimping portion 9 e. It becomes easy to deform in the direction toward the wearer's body with the front extension crimped part 9 f as the starting point of bending. Therefore, the sanitary napkin is fitted to the front of the wearer's crotch.

Similarly, also in the rear region, the region sandwiched between the rear extension crimping portion 9 g and the right edge 1 a and the region sandwiched between the rear extension crimping portion 9 h and the left edge lb are the rear extension crimping portion. It becomes easy to deform in the direction toward the wearer's body with 9 g and the rear extension crimping section 9 h as the starting point of bending. Therefore, the sanitary napkin is deformed so as to follow the shape of the buttocks of the wearer, and the body becomes fit to the wearer.

In addition, since the liquid guide layer 5 does not extend over the pressure-bonding portion 190, it is easy to form the pressure-bonding portion 190 in a uniform compressed state. In the embodiments shown in FIG. 1, FIG. 2, FIG. 7, FIG. 8, and FIG. 10, diffusion of menstrual blood outside the central absorption region 11 is provided by providing the liquid guide layer 5. Since it is unlikely to occur, almost the entire surface of the skin side is formed with a liquid-permeable surface sheet, and the liquid-impermeable sheets 22 and 22 and the wing portion as shown in Fig. 9 and Fig. 11 are formed. Even without the provision of 21 and 21, it is easy to prevent lateral leakage of menstrual blood. In addition, as in the embodiments shown in FIGS. 1, 2, 7, 9, 10, and 11, especially, a long and wide hub guard portion is provided in the rear portion as shown in FIG. Even if it is not provided, it is easy to prevent menses from leaking in the direction of the buttocks.

Further, the sanitary napkin according to the embodiment of the present invention has, as shown in FIGS. 12A and 12B, leak-proof walls 50 and 50 A extending vertically on both left and right sides of the skin side surface. It may be.

The leak-proof walls 50 and 5OA are formed by folding two sheets 22 together and sandwiching an elastic member 51 extending in the longitudinal direction inside thereof. FIG. 12A and FIG. 12B are cross-sectional views of the sanitary napkin cut along the horizontal center line Ox—Ox. It is further folded near both end edges in the direction, and the whole is adhered and fixed to the surface sheet 6. The elastic member 51 is fixed to the sheet 22 in a state where the elastic member 51 is stretched at a predetermined elongation in the longitudinal direction.

Due to the contraction force of the elastic member 51, the sanitary napkin has a curved shape. As a result, the sheet 22 rises in a predetermined range before and after the lateral center line Ox—Ox, and the leak-proof wall is formed. 50, 5 OA is formed.

By providing the leak-proof walls 50, 50A, the lateral leakage of the liquid can be further prevented, and the sanitary napkin is curved as described above, so that it fits and fits the wearer's crotch.

The sheets 22 forming the leak-proof walls 50 and 50 A are shown in FIG. 12A. It may be simply provided as shown in FIG. 12B, or may be attached so as to be caught between the lower absorber 3 and the back sheet 2 together with the top sheet 6 as shown in FIG. 12B. .

Next, an example of a method for manufacturing the sanitary napkin 1 will be described with reference to FIGS.

The nonwoven fabric 101 such as an air-through nonwoven fabric for forming the liquid guide layer 5 is wound in the form of a raw fabric 100. The nonwoven fabric 101 passes through a first drive roll 102 and is supplied to a heating unit 103. The heating unit 103 is provided with a hot air device 104, and hot air 105 is applied to the nonwoven fabric 101 from a hot air port (not shown) of the hot air device 104. Sprayed.

The blowing of the hot air 105 restores the bulk of the nonwoven fabric 101. The bulk 1. 5 allowed to recover in the range 3 times the density at this time becomes 0. ◦ 0 5 g Z cm 3 ~0. 0 2 range of g Z cm ^3. The temperature of the hot air blown from the hot air device 104 is preferably equal to or higher than the softening temperature of the material having the lowest softening temperature among the materials constituting the air-through-nonwoven fabric, and It is more preferable to heat the material to a temperature equal to or higher than the softening temperature of the material having high hardness. Specifically, the heating temperature is in the range of 130 ° C. to 300 ° C.

The nonwoven fabric 101 whose thickness has been recovered is supplied to the cooling device 107 before, after, or at the same timing as passing through the second drive roll 106. The nonwoven fabric 101 is rapidly cooled by the air blown from the nozzle 107a of the cooling device 107. The cooling device 107 may be provided as a pair so as to face both the front and back surfaces of the nonwoven fabric 101.

When the non-woven fabric 101 whose bulk has been recovered by heating is cooled, Since the fibers forming the non-woven fabric 101 are fixed in a short time, the non-woven fabric 101 can immediately maintain the state where the bulk is recovered. Therefore, even if tension is applied to the nonwoven fabric 101 immediately after transport, the bulk of the nonwoven fabric 101 does not collapse, and the bulk can be recovered immediately when the tension is released.

In particular, when the nonwoven fabric 101 is an air-through nonwoven fabric made of thermoplastic fibers, the temperature of the material constituting the nonwoven fabric becomes lower than the softening temperature by cooling. Therefore, even if the tension is applied, it is possible to prevent the nonwoven fabric 101 from stretching and reducing its bulk.

In the case of the transfer device shown in FIG. 13, the rotating speed of the first drive roll 102 provided before the heating unit 103 is provided after the heating unit 103. It is preferable that the rotation speed is equal to or higher than the rotation speed of the second drive roll 106. When heat-treated by the heating unit 103, the nonwoven fabric 101 increases in bulk and contracts in the transport direction. Therefore, the rotation speed of the second drive roll 106 located downstream of the heating unit 103 is made faster than the rotation speed of the first drive roll 102 located upstream of the heating unit 103. Then, even if the bulk is recovered by the heating unit 103 once, the nonwoven fabric 101 is stretched again in the transport direction under the tension from the second drive roll 106, and the bulk is recovered. Tends to decrease. By making the rotation speed of the second drive roll 106 equal to or slower than that of the first drive roll 102, the non-woven cloth 101 becomes Tension can be prevented from being applied in the transport direction, and a bulky state can be maintained.

In addition, when the cooling device 107 is provided in a stage preceding the second drive roll 106, the nonwoven fabric 101 can be more effectively kept in a state where the bulk has been recovered. The non-woven fabric 101 whose bulk has been recovered is, for example, a three-ply fabric as shown in FIG. After that, the liquid is supplied between the rolls 108 and 109 and trimmed into a predetermined shape to form the liquid guide layer 5. The liquid guide layer 5 is sent to the rolls 113, 114 by being sucked by a conveyor or the like.

The nonwoven fabric 1 1 1 such as an air-through nonwoven fabric for forming the topsheet 6 is wound in the form of a raw material 110. After the nonwoven fabric 1 1 1 has passed through the roll 1 12, the nonwoven fabric 1 1 1 and the liquid guide layer 5 are stacked on each other with the rolls 1 13 and 1 14 interposed therebetween, and a liquid permeation hole forming roll 1 15 , Supplied between 1 and 16.

A plurality of heated pins are provided on the surface of the roll 115 facing the nonwoven fabric 111 forming the surface sheet 6 among the liquid permeable hole forming rolls. The surface of the roll 116 opposite to 5 is a flat surface.

When the stacked nonwoven fabric 1 1 1 and the liquid guide layer 5 are supplied between the liquid permeation forming rolls 1 15 and 1 16, the heated pin is stabbed into the nonwoven fabric 1 1 1 and the nonwoven fabric 1 1 A large number of liquid permeation holes 15 are formed from 1 to the liquid guide layer 5. Since the nonwoven fabric 111 and the liquid guide layer 5 contain thermoplastic fibers, the thermoplastic fibers are fused by inserting a heated pin, and the nonwoven fabric 111 is formed at the liquid permeable holes 15. 1 and liquid guide layer 5 are adhered to each other. Therefore, it is not necessary to apply an adhesive to the interface between the nonwoven fabric 111 and the liquid guide layer 5, but the nonwoven fabric 111 and the liquid guide layer 5 are bonded to the liquid permeable hole forming rolls 115, 116. An adhesive may be applied to the interface between the nonwoven fabric 11 and the liquid guide layer 5 before passing through.

On the surface of the pulp stacking drum 120, pulp forming the upper absorber 4 and the lower absorber 3 is stacked and held in a predetermined shape. The pulp laminate 121 supplied from the pulp stack drum 120 is placed on a tissue 125 fed out from a raw fabric 123, and It is sandwiched between 1 2 5 and tissue 1 2 4 drawn out from the web 1 2 2.

Nozzle 126 applies a hot-melt adhesive to corrugated pattern or spiral pattern on pulp laminate 121 sandwiched between tissues 124 and 125. This hot melt adhesive is applied to the outer surface of the tissue 125 that covers the pulp constituting the upper absorbent core 4.

The pulp laminate 121, the nonwoven fabric 111, and the liquid guide layer 5 are supplied while being overlapped between rolls 127, 128, and are supplied by the hot melt type adhesive. 5 and the tissue 1 2 5 covering the surface of the pulp laminate 1 2 1 are adhered.

Further, a laminate composed of the nonwoven fabric 111, the liquid guide layer 5, and the pulp laminate 121 wrapped with the tissues 124 and 125 is embossed with the embossed holes 1229 and 130. The crimping section 9 shown in FIG. 1 is formed.

The crimping section 9 is made by applying a flat roll 12 9 to the outer surface of a tissue 12 4 covering the pulp laminate 12 1, and heating the roll 1 having an embossed pattern projection on the outer surface of the nonwoven fabric 1 11. The pulp laminate 121 and the nonwoven fabric 111 are locally pressed and heated. Further, a hot melt type adhesive is applied to the outer surface of the tissue 124 by the nozzle 13.

A non-moisture permeable film 133 forming the back sheet 2 is drawn from the raw material 132. The film 133 and the laminate are pressed and bonded between the rolls 134, 135 to form a laminate in which the films 133 are stacked.

Then, the laminate is supplied between the force rolls 1336 and 1337, and the sanitary napkin 1 having the shape shown in FIG. 1 is cut out. FIGS. 14 to 16 show other examples of the heating unit 103. In FIG. 14, the nonwoven fabric 101 is fed into the heating device 140. Hot air 1401 is blown into the heating device 140, and the heating device 140 is in a state of being uniformly heated. For this reason, both the front and back surfaces of the nonwoven fabric 101 are heated in the heating device 140, and the bulk of the nonwoven fabric 101 can be more effectively recovered.

The heating unit 103 in FIG. 15 includes heating rolls 142 and 144. The nonwoven fabric 101 is heated by being wound around the heating rolls 142 and 144.

The heating rolls 142 and 144 are separated from each other and have a smooth surface. The nonwoven fabric 101 is wound and transported around the heating ports 144 and 144 without being pressed between the heating rolls 142 and 144. At this time, one surface of the non-woven fabric 101 is brought into contact with the surface of the heating roll 142 to be heated, and the other surface of the non-woven fabric 101 is brought into contact with the surface of the heating roll 144. Therefore, the nonwoven fabric 101 is heated from both front and back surfaces by the two heating rolls 142, 144. In FIG. 16, a rotating drum 144 is provided between the first drive port 102 and the second drive roll 106. At a predetermined distance from the outer peripheral surface of the rotary drum 144, there is provided a hot air device 144 having a surface having a hot air blowing port curved along the outer peripheral surface of the rotary drum 144. A predetermined space is provided between the hot air device 144 and the rotating drum 144, and the nonwoven fabric 101 comes into contact with the hot air device 144 when passing over the rotating drum 144. Not to be.

When the nonwoven fabric 101 passes over the rotating drum 144, hot air is blown to the nonwoven fabric 101 from a hot air blowing port (not shown) provided in a hot air device 144. 47 is sprayed, and the bulk of the nonwoven fabric 101 is recovered. Will be restored. It is preferable that the rotating drum 145 itself be heated, since both the front and back surfaces of the nonwoven fabric 101 can be heated and the bulk can be effectively recovered.

The relationship between the rotation speed of the first drive roll 102 and the second drive roll 106 and the description of the cooling device 107 are the same as those described with reference to FIG. Here, it is omitted.

Note that the heating unit 103 and the cooling device 107 described above are also provided in the conveyance path of the nonwoven fabric 111 forming the surface sheet 6, and the nonwoven fabric 111 is bulked together with the nonwoven fabric 101. You may recover.

After the nonwoven fabric 11 and the liquid guide layer 5 are overlapped, the nonwoven fabric 11 and the liquid guide layer 5 may be heated and cooled together. Example

(Example A)

Hereinafter, the performance of Examples of the absorbent article of the present invention will be described in comparison with Comparative Examples. In the following Examples and Comparative Examples, sanitary napkins having the structures shown in FIGS. 1 to 4 were prototyped.

(Size)

The length of the napkin at the longitudinal centerline is 210 mm, the width at the transverse centerline is 80 mm, the longitudinal dimension L2 at the longitudinal centerline of the central absorbent area is 94 mm, and the width The lateral dimension W2 at the center line in the direction was set to 29 mm.

(Crimp condition)

The width Wa = 3 mm, the width dimension of the fusion portion 9D. = 0.7 mm, and the pitch P = 2.7 mm. This pressure-bonded portion was formed at a temperature of the embossing roll of 120 ° C. and a pressure of 1.76 kPa.

(1) Example As the surface sheet 6, the core is made of polyethylene terephthalate (PET) containing about 1.0% by mass of titanium oxide, and the sheath is a core-sheath composite synthetic fiber of polyethylene (PE) with a fineness of 2.2 dt. ex, an air-through nonwoven fabric with a fiber length of 44 mm. Of the synthetic fibers, 80% by mass was coated with a hydrophilic oil agent, and 2% by mass was coated with a water-repellent oil agent. The density was 0.083 g / cm ³ and the basis weight was 25 g / m ² .

The liquid guide layer 5 is an eccentric core-in-sheath type composite synthetic fiber having a core of polypropylene (PP) and a sheath of polyethylene (PE) having a fineness of 4.4 dt ex and a fiber length of 50 mm. An air-through nonwoven fabric was used. The one having a density of 0.042 gZcm ³ and a basis weight of 20 gZm ² was used. This non-woven cloth was folded so as to be three layers.

The surface sheet 6 and the liquid guide layer 5 are sandwiched between dies with pins of 110 ° C and holes of 120 ° C, and a liquid permeable hole with an opening diameter lmm, pitch Hy = 3.75mm, and Hx = 2.0mm. Formed.

As the upper absorber 4, a chemical pulp laminate having a basis weight of 230 g / m ² , a vertical dimension of 120 mm, and a maximum horizontal dimension of 55 mm was used. As the lower absorber 3, a mixture of 160 gZm ^{2 of} chemical pulp and 8 g / m ^{2 of} superabsorbent polymer with a vertical dimension of 180 mm and a maximum horizontal dimension of 75 mm was used. In a state where the upper absorber 4 and the lower absorber 3 were overlapped, the surface of the upper absorber 4 and the lower surface of the lower absorber 3 were covered with a tissue having a basis weight of 15 gZm ² as an absorption layer. .

As the liquid-impermeable and air-permeable back sheet 2, a polyethylene (PE) film having fine air holes was used.

At the interface between the liquid guide layer 5 and the upper absorber 4, a width of hot-melt adhesive is applied. Spiral of 18 mm, 3 g / m ^{2 was} applied and adhered.

(2) Comparative example 1

Comparative Example 1 in which the liquid guide layer 5 has a width of 55 mm and a vertical dimension of 120 mm as the liquid guide layer 5 and has the liquid guide layer 5 interposed between the crimping portions 9 is used. .

(3) Comparative example 2

A prototype of Comparative Example 2 in which the liquid guide layer 5 of the above-described example was omitted was produced. As the surface sheet 6, an air-through nonwoven fabric containing no water-repellent fiber, having the same basis weight and the same density as in the example was used. Only the surface sheet 6 was provided with the same liquid permeation hole as that of the example.

(4) Measurement of liquid diffusion characteristics

As artificial menstrual blood, 4.0 g of ion-exchanged water, 300 g of glycerin, 30 g of carboxymethylcellulose sodium, and 40 g of sodium chloride were added, which was colored red and red. . An acryl plate (self-weight: 115 g) having a long hole with a vertical opening of 40 mm and a width of 10 mm in the width direction was installed in both the example and the comparative example. The artificial menstrual blood was supplied to the central part of the area. At an injection rate of 95 ml / min, 3 ml was supplied the first time, and after the liquid ran out from the surface, 4 ml was supplied the second time, and 3 ml was supplied the third time when the liquid ran out from the surface.

Then, the diffusion size of the liquid in the lateral direction on the surface sheet was measured.

(5) Measurement results

In the example, the dimension was 21 mm, in Comparative Example 1, the dimension was 29 mm, and in Comparative Example 2, the dimension was 34 mm.

(Example B)

Next, the performance of the liquid guide layer used for the absorbent article was compared with the examples and comparative examples. This will be described in comparison with the above.

In the following Examples 1-6 to Comparative Examples 1-4, the following air-through nonwoven fabric was prototyped as a liquid guide layer.

(1) Example 1

An eccentric core-in-sheath composite synthetic fiber with a core of polypropylene (PP) and a sheath of polyethylene (PE), a fineness of 4.4 dt ex, a fiber length of 50 mm, and a basis weight of 20 g / m ² Was formed. The nonwoven fabric was heat-treated in an oven at 135 ° C. for 1 minute to recover the bulk, and then left for 30 minutes in an environment at room temperature of 20 ° C. and a relative humidity of 60%. (2) Example 2

The same air-through nonwoven fabric as in Example 1 was heat-treated in an oven at 145 ° C for 1 minute, and then left for 30 minutes in an environment at room temperature of 20 ° C and a relative humidity of 60%.

(3) Example 3

The same air-through nonwoven fabric as in Example 1 was heat-treated in an oven with hot air at 160 ° C. for 1 minute, and then left in an environment at room temperature of 20 ° C. and a relative humidity of 60% for 30 minutes.

(4) Example 4

An eccentric core-in-sheath composite synthetic fiber with a core of polyethylene terephthalate (PET) containing 1.1% by mass of titanium oxide and a sheath of polyethylene (PE) with a fineness of 2. An air-through nonwoven fabric having a basis weight of 25 g / m ² was formed using 2 dtex and a fiber length of 44 mm. The nonwoven fabric was heat-treated in an oven at 135 ° C for 1 minute, and then left for 30 minutes in an environment at room temperature of 20 ° C and a relative humidity of 60%.

(5) Example 5

The same air-through-non-woven fabric as in Example 4 was heated in an oven at 145 ° C with hot air. For 1 minute, and then left for 30 minutes in an environment with a room temperature of 20 ° C and a relative humidity of 60%.

(6) Example 6

The same air-through nonwoven fabric as in Example 4 was heat-treated in an oven with hot air at 160 ° C. for 1 minute, and then left for 30 minutes in an environment at a room temperature of 20 ° C. and a relative humidity of 60%.

(7) Comparative example 1

The same air-through nonwoven fabric as in Example 1 was used without heat treatment ο

(8) Comparative example 2

The same air-through nonwoven fabric as in Example 1 was heat-treated in an oven with hot air at 115 ° C. for 1 minute, and then left in an environment at room temperature of 20 ° C. and a relative humidity of 60% for 30 minutes.

(9) Comparative example 3

The same air-through nonwoven fabric as in Example 4 was used without heat treatment.

(10) Comparative example 4

The same air-through nonwoven fabric as in Example 4 was heat-treated in an oven with hot air at 115 ° C for 1 minute, and then allowed to stand for 30 minutes in an environment at room temperature of 20 ° C and a relative humidity of 60%.

(11) Thickness Measurement of Air-Through Nonwoven Fabrics of Examples and Comparative Examples Air-through nonwoven fabrics of the Examples and Comparative Examples were cut out to a size of 100 × 100 mm to obtain samples. The sample was sandwiched between two acryl plates, each 100 × 200 mm and weighing 70 g.

Each sample was sandwiched between acryl plates, and the thickness of each sample was measured using a thickness gauge (UF-6OA model) manufactured by Daiei Kagaku Seiki Seisakusho. This This was defined as the “thickness when dry”. The thickness was measured one minute after the terminal of the thickness gauge was placed on the acrylic plate, and the same applies hereinafter. Next, each sample was completely immersed in the artificial menstrual blood described in Example A and immediately pulled up. Thereafter, each sample was sandwiched between the above acryl plates, and the thickness of the sample was measured using the thickness gauge. This was defined as the “thickness when wet”.

Next, each sample was completely immersed in the artificial menstrual blood, and then immediately pulled out. With the sample sandwiched between the acryl plates, a weight of 930 g was placed on the terminal of the thickness gauge and pressure was applied to the acryl plate. 980 Pa (10 g / cm ² ) was provided. One minute after placing the terminal of the thickness gauge on the acryl plate, the thickness of the sample was measured. This was defined as the “thickness when wet and under pressure”.

Next, the weight was removed to restore the thickness of each sample, and after one minute, the thickness was measured in the same manner. This was referred to as the “recovered thickness”.

Table 1 shows the thickness of each sample when dry, the thickness when wet, the thickness when pressurized in the wet state, and the restored thickness.

dry thickness 2.46 2.88 2.21 2.28 2.2 "08 2.33 0.62 1.81 wet thickness 2.31 2.56 2.66 2.24 2.2 2.18 0.7 2.07 0.56 1.72 wet pressure thickness 0.54 0.64 0.84 0.87 0.83 0.9 0.2 0.4 0.15 0.57 restoration thickness 1.17 1.43 1.61 1.62 1.56 1.58 0.37 0.88 0.32 1.27

* Unit is mm

Table 2 shows the density when dry, the density when wet, the density when pressurized in the wet state, and the restoration density.These are the thicknesses shown in Table 1 and the air-through of each sample. It was calculated from the basis weight of the nonwoven fabric.

One six

8C.S0l / C0 OAV (12) Liquid diffusion test

From the air-through nonwoven fabric of each of Examples 1 to 6 and Comparative Examples 1 to 4, three sheets having a size of 100 × 100 mm were cut out, and a stack of the sheets was subjected to liquid guide for measurement. Layers.

An eccentric core-in-sheath composite with a core made of polyethylene terephthalate (PET) containing 1.1% by mass of the fiber mass of titanium oxide and a sheath made of polyethylene (PE). A non-woven fabric was used which had a fiber fineness of 2.2 dt ex, a fiber length of 44 mm, and a basis weight of 25 gZm ² . A surface sheet was cut from the nonwoven fabric to a width of 100 mm and a length of 200 mm.

As an absorption layer for measurement, an upper absorber with a vertical dimension of 120 mm and a width dimension of 55 mm was superimposed on a lower absorber with a vertical dimension of 180 mm and a width dimension of 75 mm. Is a chemical pulp laminated to have a basis weight of 23 O gZm ² , and the lower absorber is a mixture of chemical pulp (basis weight 160 gZm ² ) and superabsorbent polymer (8 g / m ² ) It is. Both sides of the absorbent layer are covered with tissue with a basis weight of 15 gZm ² . The absorption layer, the liquid guide layer, and the topsheet are stacked on an acryl plate having a width of 100 mm and a length of 200 mm. Place another acrylic plate with a length of 40 mm and a width of 10 mm in the center (100 mm in width, 100 mm in width, 200 mm in length in the vertical direction) on the surface sheet, The slot was set so as to be located at the center of the sample. The artificial menstrual blood was supplied from the slot. At an injection rate of 95 ml / min, 3 ml was supplied the first time, and 30 seconds after the liquid ran out of the sample surface, 4 ml was supplied a second time at the same injection rate and the liquid ran out of the surface. Thirty seconds later, a third injection of 3 ml was made at the same injection rate.

After the third injection, make sure that no liquid has run out of the sample surface. One minute after the removal, the acryl plate having a long hole was removed, and the maximum diffusion dimension of the liquid in the vertical and horizontal directions on the surface sheet was measured.

Table 3 shows the measurement results.

Table 3

First penetration 4.95 4.68 4.19 5.06 4.96 5.08 6.82 5.15 9.35 5.41

Second penetration time 7.32 6.44 6.47 8.18 6.83 7.27 13.01 7.95 22.7 9.53

3rd penetration time 7.71 7.07 6.96 8.41 8.24 8.17 16.54 9.91 30.15 11.78 Diffusion width 64 62 61 63 60 62 69 69 62 67 Diffusion width length 36 35 35 34 33 32 42 40 28 37 Penetration speed evaluation OOOO 評価 OXOXO Diffusion width evaluation OOOO 〇 OXXO

As shown in Table 1, the nonwoven fabrics of Examples 1 to 6 in the wet state have a thickness of 0.5 mm or more and 1 mm or less when pressed, and the restored thickness is 1 mm or more and 2 mm or less. Therefore, the thickness of the obtained liquid guide layer when pressurized in a wet state is 1.5 to 3 mm, and the restored thickness is 3 to 6 mm. Density of the dry nonwoven fabric of Example also, 0.005 to 0. Was 02 g / cm ^3, the density of and under pressure at the time of moisture ^{Jun, 0. 005 gZcm 3 ~0. 04} gZc m 3 It is.

While the invention has been illustrated and described with respect to embodiments thereof, it will be obvious to those skilled in the art that the foregoing and various other changes, omissions, and additions can be made without departing from the spirit and scope of the invention. Will be understood. Therefore, the invention is not to be understood as being limited to the particular embodiments described herein, but is intended to be embodied within the scope of equivalents encompassed by the features in the appended claims. Embodiments are included.

Industrial applicability

As described above, according to the present invention, the liquid repeatedly supplied in a limited area in the central absorption region of the absorbent article can be rapidly drawn in, and the diffusion of the liquid on the topsheet can be prevented. The absorbent article can also effectively prevent side leakage. In particular, since the central absorbent region of the absorbent article can securely adhere to the excretory organ of the wearer, it can be worn comfortably and can absorb liquid concentrated in the central absorbent region.

Claims

The scope of the claims

1. Back sheet (2)

A liquid-permeable topsheet (6),

An absorbent article comprising a back sheet (2) and a liquid-permeable top sheet (6), comprising a hydrophilic material, and an absorbent layer comprising:

At a position separated by a predetermined distance on both the left and right sides from the center line (Oy-Oy) extending in the longitudinal direction of the absorbent article, the absorbent layer is compressed together with the topsheet (6), and the crimped portion having a concave shape is formed in the longitudinal direction. The central absorbent region is formed so as to extend continuously, and defines a central absorbent region between the press-fit portions, and an auxiliary absorbent region outside the crimp portion. In the central absorbent region, the central absorbent region is formed between the absorbent layer and the topsheet (6). In between, a liquid guide layer (5) made of fibers joined so as to leave voids therein and having a lower density than the absorbing layer is provided so as not to overlap with the pressure-bonded portion. The absorbent layer is covered with the topsheet (6).

2. The crimping portion further extends and is continuous with each other, enclosing a predetermined range as the central absorption region, wherein the liquid guide layer (5) has an area smaller than the central absorption region, and 2. The absorbent according to claim 1, which does not overlap.

3. The absorption layer comprises a lower absorber (3) and an upper absorber (4) superimposed on the lower absorber (3), wherein the upper absorber (4) is the lower absorber. The lower absorbent body (3) and the upper absorbent body (4) are compressed together with the topsheet (6) at the pressure-bonded portion and have a concave shape. It is said that The auxiliary absorption region has a thick portion (12a) adjacent to the pressure-bonded portion, where both the lower absorber (3) and the upper absorber (4) are present, A thin part (12b) outside a thick part (12a), wherein the lower absorber (3) is present but the upper absorber (4) is not present. The absorbent article according to the above.

4. The absorbent article according to claim 1, wherein a plurality of liquid permeable holes (15) penetrating through the topsheet (6) and extending to the liquid inner layer (5) are formed in the central absorption region.

5. The chemical fibers forming the surface sheet (6) and the chemical fibers forming the liquid guide layer (5) are thermally fused around the liquid permeable hole (15). 5. The absorbent article according to claim 4, wherein:

6. The absorbent article according to claim 1, wherein the fiber density of the liquid guide layer (5) when dried is 0.00 g / cm ³ or more and 0.02 gZcm ³ or less.

7. The liquid guide layer (5), the fiber density when given a pressure of 980 P a (1 0 g / cm 2) in a wet ^{state, 0. 00 5 gZcm 3 ~0.} 04 g Zc m 3 7. The absorbent article according to claim 6, which is within the range of.

8. The absorbent article according to claim 6, wherein the liquid guide layer (5) is an air-through or air-laid nonwoven fabric made of a chemical fiber.

9. The absorbent article according to claim 8, wherein the liquid guide layer (5) is formed by folding the nonwoven fabric such that a plurality of nonwoven fabrics are stacked.