JP2009268559A - Absorbent article - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an absorbent article having improved diffusion property and absorbability of body fluid, effectively preventing a backward flow of the liquid, and reducing the stickiness and discomfort in a surface sheet. <P>SOLUTION: This absorbent article 1 has an absorber 4 interposed between a liquid permeable surface sheet 3 and a back sheet 2. The surface sheet 3 is embossed at predetermined intervals to alternately form recessed parts 8 and projecting parts 7 adjacently to each other, wherein the recessed parts 8 have hydrophilicity, the projecting parts 7 have hydrophobicity, the recessed parts 8 are defined as a high-density area D<SB>H</SB>having a relatively high fiber density and the projecting parts 7 are defined as a low-density area D<SB>L</SB>having a relatively low fiber density. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an absorbent article having a surface sheet that enhances liquid diffusibility and absorbability, effectively prevents backflow of body fluid, and reduces stickiness and discomfort.

  Conventionally, as a surface material of absorbent articles, various purposes such as reducing the contact area to the skin to suppress the moist feeling, giving a texture and enhancing the touch, or quickly transferring body fluid to the absorbent body Depending on the situation, products with appropriate embossed patterns are provided on the market. Furthermore, as the surface material, a material coated with a hydrophilic agent such as a surfactant in order to quickly absorb the discharged body fluid into the lower-layer absorber is also provided on the market.

  For example, in Patent Document 1 below, the liquid-permeable surface sheet is formed by hot embossing pressure bonding of at least two short fiber nonwoven fabrics, and absorption using at least the uppermost layer formed of a hydrophilic nonwoven fabric. A sex product is disclosed.

Further, in Patent Document 2 below, a large number of ridges and grooves are alternately arranged so as not to have a flat portion, the ridges are curved in a convex shape, and the groove portions are curved in a concave shape, An absorbent article using a nonwoven fabric having a large number of apertures arranged at intervals as the groove is used as a top sheet is disclosed. Moreover, the nonwoven fabric whose difference (ab) of the maximum sheet thickness a of the said collar part and the sheet thickness b of the lower end peripheral part of the said opening is 200 micrometers or more is used as the said surface sheet.
Japanese Patent Laid-Open No. 2005-312601 JP-A-8-302555

  However, in the absorbent article described in Patent Document 1, the entire uppermost nonwoven fabric in contact with the skin is formed of a hydrophilic nonwoven fabric, so that the body fluid discharged on the topsheet is likely to diffuse throughout the topsheet. At the same time, the body fluid is easily held on the top sheet, causing stickiness and discomfort due to the reversal of the fluid.

  On the other hand, the absorbent article described in Patent Document 2 is provided with a difference in thickness between the upper end portion and the lower end portion of the collar portion while making the basis weight of the top sheet substantially uniform as a whole. A difference in fiber density (that is, a gradient of capillary force) is generated, and this is used as a driving force to further improve the liquid mobility in the surface sheet. However, only the gradient of the capillary force due to the difference in the fiber density in the surface sheet has a limit on the absorption rate of the body fluid, and a quicker absorption of the body fluid has been desired.

  Furthermore, since the absorbent article described in Patent Document 2 has a large number of apertures in the groove portion of the top sheet, body fluid can be absorbed quickly, but the absorbed body fluid is released from the aperture portion. There was a risk of causing stickiness and discomfort by reversing.

  Therefore, an object of the present invention is to provide an absorbent article that enhances the diffusibility and absorbability of body fluids and effectively prevents the liquid from returning, and reduces stickiness and discomfort.

In order to solve the above-mentioned problem, as the present invention according to claim 1, in an absorbent article in which an absorbent body is interposed between a liquid-permeable top sheet and a back sheet,
The surface sheet is provided with embosses in a predetermined pattern so that concave portions and convex portions are alternately formed adjacent to each other, the concave portions have hydrophilicity, the convex portions have hydrophobicity, and the concave portions are relative to each other. In particular, an absorbent article is provided in which a high-density region having a high fiber density is used and the convex portion is a low-density region having a relatively low fiber density.

  According to the first aspect of the present invention, the concave portions and the convex portions are alternately formed adjacent to each other by embossing the surface sheet in a predetermined pattern. The concave portions have hydrophilicity and the convex portions have hydrophobicity. And the said recessed part is made into the high density area | region with a relatively high fiber density, and the said convex part is an absorbent article made into the low density area | region with a relatively low fiber density. As a result, when the body fluid is discharged to the top sheet, the body fluid quickly moves from the hydrophobic convex portion to the hydrophilic concave portion, so that the diffusibility of the body fluid is improved and the surface side (convex portion) Since the body fluid is not retained in the water and moves to the absorber side (recessed portion), the stickiness and uncomfortable feeling of the surface sheet are eliminated.

  In addition, since the body fluid diffused so as to collect in the recess passes through the recess having high body fluid permeability and is configured to have hydrophilicity, the body fluid is promptly absorbed by the absorber. become able to.

  Furthermore, since the recess has improved water absorption by providing hydrophilicity without providing an opening or the like, even if the body fluid absorbed by the absorber is subsequently subjected to pressure, Reversal is prevented.

  Further, by providing a fiber density gradient with the concave portion as a high density region and the convex portion as a low density region, the body fluid is transferred from the convex portion to the concave portion by making the concave portion hydrophilic and the convex portion hydrophobic. Is further promoted, and the body fluid moves more quickly on the concave side, so that the diffusibility becomes better.

  The present invention according to claim 2 uses a non-woven fabric having hydrophobicity as a material fiber constituting the top sheet, and simultaneously with embossing, a hydrophilizing agent is applied to the region that becomes the recess. An absorbent article is provided.

  In the second aspect of the present invention, a non-woven fabric having hydrophobicity is used as the material fiber constituting the top sheet, and at the same time as embossing is applied, a hydrophilizing agent is applied to the region that becomes the recess. That is, since the convex part of the surface sheet is a part that is always in contact with the skin, in order to avoid the water repellent agent from always contacting the skin, a material fiber having a hydrophobic property is used as the surface sheet, It is desirable to apply a hydrophilic treatment to the recess. Further, since the hydrophilizing agent is applied to the concave portion simultaneously with embossing, the hydrophilizing agent can be spread to a certain extent by the pressure action by the embossing.

  As the present invention according to claim 3, a second sheet made of a porous plastic film having a large number of openings or a non-woven sheet having a higher hydrophilicity than the surface sheet is disposed on the lower surface side of the surface sheet. An absorbent article according to any one of claims 1 and 2 is provided.

  In the invention of claim 3, a second sheet made of a porous plastic film in which a large number of openings are formed or a non-woven sheet having a higher hydrophilicity than the surface sheet is disposed on the lower surface side of the surface sheet. After the body sheet diffuses so that the body fluid gathers in the recesses in the top sheet, many of them pass through the second sheet made of a porous plastic film or non-woven sheet with high body fluid permeability disposed on the lower layer side and reach the absorber, and then Even if pressure is applied to this, it is possible to prevent reversion.

  As this invention which concerns on Claim 4, the said surface sheet is comprised with the multilayer nonwoven fabric, and the fineness of the nonwoven fabric of each layer of an absorber side becomes small sequentially with respect to the fineness of the surface layer nonwoven fabric arrange | positioned by the use surface side. The absorbent article according to any one of claims 1 to 3 set as described above is provided.

  In the invention according to the fourth aspect, the top sheet is composed of a multilayer nonwoven fabric. And this laminated nonwoven fabric is set so that the fineness of the nonwoven fabric of each layer of an absorber side may become small sequentially with respect to the fineness of the surface layer nonwoven fabric arrange | positioned at the use surface side.

  Accordingly, since the density gradient due to the fineness is formed in the absorption direction in the surface sheet, the body fluid discharged to the use surface side and transferred to the concave portion quickly moves to each layer on the absorber side due to the density gradient due to the fineness. Then, it passes through the top sheet and the second sheet and is quickly absorbed by the absorbent body, and the smooth feeling of the surface is easily maintained.

  As this invention which concerns on Claim 5, the said surface sheet is comprised with the multilayer nonwoven fabric, and with respect to the fiber density of the surface layer nonwoven fabric arrange | positioned at the use surface side, the fiber density of the nonwoven fabric of each layer by the side of an absorber is in order. The absorbent article in any one of Claims 1-3 set so that it may become high is provided.

  In the invention according to the fifth aspect, the top sheet is composed of a multilayer nonwoven fabric. And this laminated nonwoven fabric is set so that the fiber density of the nonwoven fabric of each layer by the side of an absorber may become high sequentially with respect to the fiber density of the surface layer nonwoven fabric arrange | positioned by the compression process etc. at the use surface side.

  Therefore, since the fiber density gradient is formed in the absorption direction in the top sheet, the body fluid discharged to the use surface side and transferred to the concave portion moves quickly to each layer on the absorber side due to the fiber density gradient. Then, it passes through the top sheet and the second sheet and is quickly absorbed by the absorbent body, and the smooth feeling of the surface is easily maintained.

  The absorbent article according to any one of claims 4 and 5, wherein a cover nonwoven fabric having a fineness smaller than that of the surface nonwoven fabric is disposed on the use surface side of the topsheet as the present invention according to claim 6. Provided.

  In the invention of claim 6, in consideration of the fact that the fineness of the surface nonwoven fabric is deteriorated, the feeling of touch is deteriorated, and a thin cover nonwoven fabric smaller than the fineness of the surface nonwoven fabric is disposed on the use surface side of the surface sheet. It is what I did.

  As described above, according to the present invention, it is possible to obtain an absorbent article that enhances the diffusibility and absorbability of the liquid, effectively prevents the body fluid from returning, and reduces stickiness and discomfort.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a partially broken perspective view of a sanitary napkin 1 according to the present invention.

[Structure of absorbent article 1]
The sanitary napkin 1 is mainly used for applications such as panty liners, sanitary napkins, cage sheets, and incontinence pads. For example, as shown in FIG. Between the liquid-permeable surface sheet 3 (hereinafter, simply referred to as a surface sheet), as shown in the figure, the absorber 4 or the absorber 4 preferably surrounded by the crepe paper 5 is interposed, Between the surface sheet 3 and the absorbent body 4, a second sheet 6 made of a porous plastic film or a nonwoven fabric sheet having a large number of openings formed on the lower surface side of the surface sheet 3 is arranged. In addition, in the circumference | surroundings of the said absorber 4, the said liquid-impermeable back sheet 2 and the surface sheet 3 are joined by adhesion | attachment means, such as a hot-melt-adhesive.

  The liquid-impervious back sheet 2 is made of a sheet material having at least water-impervious properties such as polyethylene and polypropylene, but in addition to this, a non-woven sheet after securing a substantially liquid-impervious property through a waterproof film. (In this case, a liquid-impervious back sheet is composed of the waterproof film and the nonwoven fabric). In recent years, those having moisture permeability tend to be suitably used from the viewpoint of preventing stuffiness. The water- and moisture-permeable sheet material is a microporous material obtained by melting and kneading an inorganic filler in an olefin-based resin such as polyethylene or polypropylene to form a sheet, and then stretching in a uniaxial or biaxial direction. A sheet is preferably used.

  The surface sheet 3 is made of a non-woven fabric of heat-fusible fibers, and is provided with recesses 8, 7... And protrusions 7, 7. , 8... Are hydrophilic and the convex portions 7, 7... Are hydrophobic. The surface sheet 3 will be described in more detail later.

  The absorbent body 4 interposed between the liquid-impermeable back sheet 2 and the top sheet 3 is, for example, a mixture of a superabsorbent resin in pulp, or a mixture of chemical fibers in the pulp, What mixed the superabsorbent resin is used. As shown in the figure, it is desirable that the absorbent body 4 is surrounded by crepe paper 5 in order to maintain its shape and quickly diffuse menstrual blood and prevent reverse return of menstrual blood once absorbed. Examples of the pulp include chemical fibers obtained from wood, cellulose fibers such as molten pulp, and those made of artificial cellulose fibers such as rayon and acetate. It is preferably used in terms of price.

  Examples of the superabsorbent resin include cross-linked polyacrylate, self-crosslinked polyacrylate, saponified acrylate-vinyl acetate copolymer cross-linked, isobutylene / maleic anhydride copolymer cross-linked, Examples include cross-linked polysulfonates, and partially cross-linked water-swellable polymers such as polyethylene oxide and polyacrylamide. Of these, those based on acrylic acid or acrylate that are excellent in water absorption and water absorption speed are preferred. In the production process of the highly water-absorbent resin having the water absorption performance, the water absorption force and the water absorption speed can be adjusted by adjusting the crosslinking density and the crosslinking density gradient. The content of the superabsorbent resin is preferably 10 to 60%. When the content of the superabsorbent resin is less than 10%, sufficient absorbability cannot be provided, and when it exceeds 60%, the entanglement between the pulp fibers disappears, the sheet strength decreases, and tears, cracks, etc. Is likely to occur.

  As shown in FIG. 5, it is desirable that the superabsorbent resin 9 is unevenly distributed and mixed so that the content on the second sheet 6 side is larger than that on the back sheet 2 side. Thereby, the body fluid that has reached the second sheet 6 can be effectively drawn into the absorber 4.

  The second sheet 6 disposed between the liquid-permeable surface sheet 3 and the absorbent body 4 is a film sheet having a higher hydrophilicity than the surface sheet 3 and having a large number of apertures 6a, 6a. is there. As the material of the film, for example, an olefin-based thermoplastic resin film such as polyethylene or polypropylene is preferably used, but a polyamide-based resin such as polyester or nylon, EVA, or the like can also be used.

The diameter of the opening 6a is 0.05 to 2.0 mm, preferably 0.1 to 1.0 mm, and the number of openings is preferably about 200 to 600 holes / cm ² . In order to form the opening 6a, the synthetic resin sheet is softened near the softening temperature and is positioned on the upper surface of the support having a large number of openings, and is sucked from below the support. It is opened by pressing the air pressure from the top surface of the sheet, by engraving a lot of slits in the synthetic resin sheet material and then stretching and opening the sheet material, and by piercing many needles (heating needles). There are various methods, such as a method of forming a hole, which can be formed by an appropriate method, but in order to prevent the bodily fluid that has once passed through, the needle is opened as shown in FIG. In addition, it is desirable to form a funnel shape in which the opening diameter d1 on the surface sheet 3 side is larger than the opening diameter d2 on the absorber 4 side. FIG. 4A shows an embodiment in which the opening is formed in an inverted truncated cone shape, and FIG. 4B shows an embodiment in which the opening is formed in an irregular shape. Further, in the accompanying drawings, openings other than those in FIG. 4 are omitted.

[Surface layer structure comprising the top sheet 3 and the second sheet 6]
As described above, the surface sheet 3 is formed by embossing in a predetermined pattern so that the concave portions 8, 8... And the convex portions 7, 7. is a hydrophilic region W _h having a hydrophilic, the convex portion is the hydrophobic region W _r having hydrophobic. Furthermore, the recess 8, 8 ... are the relatively high fiber density high density region D _H, the convex portions 7, 7 is set to relatively low fiber density and low density regions D _L.

  As a raw material fiber which comprises this surface sheet 3, it can be set as synthetic fiber which has hydrophobicity, such as olefin type, such as polyethylene or a polypropylene, a polyester type, a polyamide type, for example. On the other hand, as the material fiber constituting the surface sheet 3, a hydrophilic fiber such as regenerated fiber such as rayon or cupra, natural fiber such as cotton, etc. can be used.

That is, to the recess 8, 8 ... to the topsheet 3 as hydrophilic regions W _h, the convex portions 7, 7 is hydrophobic region W _r is appropriately as follows, hydrophilic treatment or repellent Apply water treatment. Specifically, when using the above-described hydrophobic fiber as the material fiber constituting the top sheet 3, by applying a hydrophilic treatment to the region that becomes a recess by embossing, the recess 8, 8 ... it is possible to obtain the surface sheet 3 and the hydrophilic region W _h. On the other hand, when using the above-mentioned hydrophilic fiber as the material fiber constituting the surface sheet 3, by applying a water repellent to the region that becomes a convex portion by embossing, the convex portions 7, 7 it is possible to obtain a surface sheet 3 was a hydrophobic region W _r. Here, the convex portions 7, 7... Of the surface sheet 3 are portions that are always in contact with the skin. Therefore, in order to avoid that the water repellent agent is always in contact with the skin, the material fibers constituting the surface sheet 3 are hydrophobic. It is desirable that the hydrophilic region W _h and the hydrophobic region W _r are respectively formed by applying a hydrophilic treatment to the recesses 8, 8. Therefore, this embodiment will be described in detail below.

  The surface sheet 3 can be a nonwoven fabric obtained by an appropriate processing method such as an air-through method, a spunlace method, a spunbond method, a thermal bond method, a melt blown method, or a needle punch method. Among these processing methods, the spunlace method is excellent in terms of flexibility and drapeability, and the air-through method and the thermal bond method are excellent in terms of being bulky and soft. Among these, it is desirable to use an air-through non-woven fabric that easily gives a fiber density gradient.

  The non-woven fiber may be either a long fiber or a short fiber, but preferably a short fiber is used in order to give a towel texture. In order to facilitate the embossing treatment, it is preferable to use an olefin fiber such as polyethylene or polypropylene having a relatively low melting point. In addition, a composite fiber such as a core-sheath fiber, a side-by-side fiber, or a split fiber having a fiber having a high melting point as a core and a fiber having a low melting point as a sheath can be suitably used.

  Examples of the hydrophilic agent (surfactant) include an anionic surfactant, carboxylate, acylated hydrolyzed protein, sulfonate, sulfate ester salt, phosphate ester salt, nonionic surfactant, Polyoxyethylene surfactants, carboxylic acid esters, carboxylic acid amides, polyalkylenoxide block copolymers, cationic surfactants, quaternary ammonium salts, amphoteric surfactants, imidazolinium derivatives, etc. In addition to this, any known surfactant may be applied as the surfactant applied to the fiber.

  Examples of the water repellent include acid chloride type water repellent, isocyanate type water repellent, ketene dimer type water repellent, pyridine condensation type water repellent, ethylene urea type water repellent, methylol compound type water repellent. , Ethylene oxide type water repellent, silicon compound type water repellent, chromium complex compound type water repellent, titanium containing compound type water repellent, zirconium containing compound type water repellent, fluorine compound type water repellent, silicon compound type water repellent A liquid medicine or the like can be used. Other water repellent agents include fats and oils (vegetable oils, animal oils, vegetable fats, animal fats), higher aliphatic compounds (saturated or unsaturated acids, alcohols, esters, amines, amides, salts), waxes (plant waxes, Animal waxes, mineral waxes, petroleum waxes, modified waxes) and the like, or modified products thereof, and mixtures thereof.

  The concave portions 8, 8,... And the convex portions 7, 7,... Are alternately formed adjacent to the surface sheet 3, and the concave portions 8, 8,. In order to provide embossing so that the convex portions 7, 7... Are in a low density region having a relatively low fiber density, as shown in FIG. 6, the convex portions 10a, 10a... And the concave portions 10b, 10b. Are constituted by a first embossing roll 10 in which a large number of ... are arranged, a second embossing roll 11 in which a large number of convex parts 11a, 11a ... and concave parts 11b, 11b ... are arranged, and in a meshed state. The convex portion 10a of the first embossing roll 10 and the concave portion 11b of the second embossing roll 11 are in contact with or close to each other, and between the first embossing roll 10 and the second embossing roll 11 are used. To the surface sea 3, the concave portions 8, 8... And the convex portions 7, 7... Are alternately formed adjacent to each other, and the fiber density is higher than that of the convex portions 7 by the high compression of the concave portions 8, 8. Can be.

  The interval P between the concave portions 8, 8... Is 2 to 6 mm, preferably 3 to 5 mm, and is formed so that the convex portions 7, 7. Further, it is desirable that the concave portions 8, 8... And the convex portions 7, 7,. Further, the height difference h is desirably 0.3 to 2 mm, preferably 0.5 to 1.0 mm.

  In order to apply the above-described hydrophilic treatment to the recesses 8 formed in this way, as shown in FIG. 6, the hydrophilizing agent is discharged from the tip of the convex portion 10 a of the first embossing roll 10. The discharge port 10c is provided, and when the surface sheet 3 is compressed between the first embossing roll 10 and the second embossing roll 11, a hydrophilizing agent is discharged from the discharge port 10c and applied to the recess 8. The Such a discharge port may be formed in the concave portion of the second embossing roll 11, or may be formed in both the convex portion 10 a of the first embossing roll 10 and the concave portion 11 b of the second embossing roll 11. .

Next, the embossing pattern will be described in detail with reference to FIGS. 7 to 10 are plan views showing an example of an embossed pattern imparted to the surface sheet 3, of the embossing applied, display the recesses 8, 8 ... which is the hydrophilic region W _h in black It is a thing.

In the first embodiment, as shown in FIG. 7, the concave portions 8, 8... Are formed in a dot shape, and the convex portions 7 are formed in the middle portion surrounded by the dot-shaped concave portions 8, 8. It is a thing. Since the concave portions 8, 8... Of the hydrophilic region W _h are formed in a dot shape and the other portions are the hydrophobic regions W _r , the portion where the hydrophilic body fluid is easily retained becomes small, and stickiness and discomfort A smooth feeling can be raised without producing.

  In the second embodiment, as shown in FIG. 8, the concave portions 8, 8... And the convex portions 7, 7. As a whole, it is formed in a wavy shape in the width direction. Since the convex portions 7, 7... Are provided over the longitudinal direction, groove-shaped concave portions 8, 8... Are formed in the longitudinal direction, and body fluid is easily transferred to the groove-shaped concave portions 8, 8,. Diffusibility and absorbency can be increased.

In the third embodiment, as shown in FIG. 9, the concave portions 8, 8... Are formed in a lattice shape, and the convex portion 7 is formed in a portion surrounded by the lattice. By the recesses 8, 8 ... of the hydrophilic region W _h a grid pattern, it is possible to continuously form a hydrophilic region W _h, it is possible to increase the diffusion of the body fluids, thereby improving the absorbability .

In the fourth embodiment, as shown in FIG. 10, the concave portions 8, 8,... Are formed in a discontinuous line shape or a dotted line shape along the longitudinal direction. This embodiment is the is the same concept as the dot-shaped first embodiment, it can be expected longitudinal diffusion in the recess 8, 8 ... of the hydrophilic region W _h.

  On the other hand, the second sheet 6 laminated on the lower surface side of the surface sheet 3 is composed of a porous plastic film or a nonwoven fabric sheet in which a large number of openings are formed. The second sheet 6 is treated with a hydrophilizing agent so as to have a higher hydrophilicity than the top sheet 3. Such imparting of hydrophilicity is achieved by applying a hydrophilizing agent (surfactant) to the front and back surfaces of the second sheet 6. As the hydrophilizing agent (surfactant), the same hydrophilizing agent (surfactant) used for the top sheet 3 can be used.

  Examples of the method for applying the surfactant include spray coating, gravure printing and flexographic printing, and curtain coating using various coaters. The hydrophilicity can be adjusted by adjusting the coating amount of the surfactant.

  Further, in the second sheet 6, as shown in FIG. 5, the hydrophilicity of the surface on the absorber 4 side is set higher than the surface on the surface sheet 3 side, and has a hydrophilicity gradient from the surface side to the back surface side. You may make it let. By providing the hydrophilicity gradient, the body fluid present on the upper surface of the second sheet 6 can be effectively drawn into the absorber 4 side.

  After the topsheet 3 is embossed in a single state, it is laminated with the second sheet 6 and preferably joined to each other at the recesses 8 of the topsheet 3. As a joining method, any method such as heat fusion, ultrasonic fusion, and adhesive can be employed. In this case, since there is a space between the second seat 6 and the convex portions 7, 7... Other than the concave portions 8, 8.

Or if the detail the surface structure, as shown in FIG. 3, the convex portions 7, 7 is a relatively low fiber density and low density regions D _L, the recesses 8, 8 ... the relative A high density region _DH having a high fiber density is formed, and a fiber density gradient from the low density region _DL to the high density region _DH is formed. As a result, when the body fluid is discharged to the surface sheet 3, the body fluid present in the convex portions 7, 7... Moves quickly toward the concave portions 8, 8. made with, for body fluid on the surface side (the low-density region D _L side) is eliminated to be water retention, so that feeling sticky is eliminated. In addition, a second sheet 6 having high permeability is disposed on the lower layer side, and the second sheet 6 is set to have a higher degree of hydrophilicity than the top sheet 3, so that the body fluid is in the recesses 8, 8. After diffusing so as to gather, most of them pass through the highly water-permeable second sheet 6 arranged on the lower layer side to reach the absorber 4, and even when pressure is applied thereafter, reversal is prevented. .

  By the way, it is preferable that the said surface sheet 3 and the 2nd sheet | seat 6 are each comprised by the single layer nonwoven fabric or the multilayer nonwoven fabric, and are made into a laminated nonwoven fabric by mutually laminating | stacking. In the example shown in FIG. 2, the top sheet 3 is composed of a two-layered nonwoven fabric of a surface nonwoven fabric 3 </ b> A and a lower layer nonwoven fabric 3 </ b> B disposed on the use surface side, and the second sheet 6 is composed of a single-layer nonwoven fabric. It has a three-layer structure. And with respect to the fineness of the surface layer nonwoven fabric 3A, the fineness of the lower layer nonwoven fabric 3B disposed on the lower absorbent body 4 side is set to be sequentially reduced, or the fiber density of the surface layer nonwoven fabric 3A It is preferable that the fiber density of the lower layer nonwoven fabric 3B disposed on the lower absorbent body 4 side is set so as to increase sequentially.

  That is, with the above configuration, the surface sheet 3 is formed with a density gradient across each layer by fineness or compression treatment. Therefore, the body fluid that has moved to the recesses 8, 8... Quickly moves to each layer on the absorber side due to the gradient of fineness or fiber density, passes through the top sheet 3 and the second sheet 6, and is quickly absorbed by the absorber 4. At the same time, even if the body fluid absorbed by the absorbent body 4 is subsequently subjected to pressure, it is prevented from returning. In addition, it is easy to maintain a light feeling.

  On the other hand, as described above, the surface sheet 3 is provided with a surface layer nonwoven fabric 3A having a large fineness on the surface side for the purpose of more effectively absorbing the body fluid due to the density gradient due to the fineness and the like. Therefore, the feeling of touch may be deteriorated. Therefore, it is preferable to dispose a thin cover nonwoven fabric having a fineness smaller than that of the surface nonwoven fabric 3A on the use surface side of the topsheet 3. While the touch nonwoven fabric provides a good feeling of touch, the lower layer side is provided with a fiber density gradient so that rapid absorption of body fluids is not hindered.

It is a partially broken perspective view of the absorbent article 1 according to the present invention. It is the principal part expanded horizontal sectional view. It is a principal part expanded sectional view of the surface sheet 3 for demonstrating an effect. (A) and (B) are the principal part expanded sectional views which show the opening aspect of the 2nd sheet | seat 6 which consists of a porous plastic film. It is a principal part expanded sectional view which shows the modification of this absorbent article. It is a figure which shows the meshing state of the 1st embossing roll 10 and the 2nd embossing roll 11. FIG. It is a top view which shows the embossing pattern (the 1) of the surface sheet. It is a top view which shows the embossing pattern (the 2) of the surface sheet. It is a top view which shows the embossing pattern (the 3) of the surface sheet. It is a top view which shows the embossing pattern (the 4) of the surface sheet.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Absorbent article (sanitary napkin), 2 ... Impervious back sheet, 3 ... Impervious surface sheet, 4 ... Absorber, 5 ... Crepe paper, 6 ... Second sheet, 7 ... Convex part, 8 ... Concave part, 9 ... high water absorption resin, 10 ... first embossing roll, 10a ... convex part, 10b ... concave part, 11 ... second embossing roll, 11a ... convex part, 11b ... concave part, 12 ... second nonwoven fabric Sheet, 20 ... laminated nonwoven fabric, D _L ... low density region, D _H ... high density region

Claims (6)

In the absorbent article in which an absorber is interposed between the liquid-permeable top sheet and the back sheet,
The surface sheet is provided with embosses in a predetermined pattern so that concave portions and convex portions are alternately formed adjacent to each other, the concave portions have hydrophilicity, the convex portions have hydrophobicity, and the concave portions are relative to each other. In particular, the absorbent article is a high-density region having a high fiber density, and the convex portion is a low-density region having a relatively low fiber density.   The absorbent article according to claim 1, wherein a hydrophobic non-woven fabric is used as the material fiber constituting the surface sheet, and a hydrophilic agent is applied to the region to be the recess simultaneously with embossing.   The second sheet made of a porous plastic film having a large number of openings or a non-woven sheet having a higher hydrophilicity than the surface sheet is disposed on the lower surface side of the surface sheet. The absorbent article as described.   The said surface sheet is comprised by the nonwoven fabric of a multilayer, and is set so that the fineness of the nonwoven fabric of each layer by the side of an absorber may become small sequentially with respect to the fineness of the surface nonwoven fabric arranged at the use side. 3. The absorbent article according to any one of 3.   The surface sheet is composed of a multilayer nonwoven fabric, and is set such that the fiber density of the nonwoven fabric of each layer on the absorber side is sequentially higher than the fiber density of the surface nonwoven fabric disposed on the use surface side. Item 4. The absorbent article according to any one of Items 1 to 3.   The absorbent article according to any one of claims 4 and 5, wherein a cover nonwoven fabric having a fineness smaller than that of the surface nonwoven fabric is disposed on the use surface side of the topsheet.

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