JP6944309B2 - Absorbent article and manufacturing method of absorbent article - Google Patents

Description

The present invention relates to an absorbent article and a method for producing an absorbent article.

Conventionally, absorbent articles such as sanitary napkins, panty liners, and incontinence pads have been known for the purpose of absorbing body fluids. Many of these absorbent articles have a basic structure comprising a body having a liquid permeable front surface sheet, a liquid impermeable back surface sheet, and an absorber provided between the two sheets. ing.

When using an absorbent article, the body fluid is discharged onto a liquid-permeable surface sheet and absorbed into the absorber through the surface sheet, but when the body fluid remains on the surface sheet, the body fluid is with the skin. Contact is likely to cause discomfort. Therefore, it is preferable not to leave body fluid on the surface sheet as much as possible. Therefore, in order to control the transfer of body fluids on the surface sheet, it is known to apply a substance to the surface sheet.

For example, Patent Documents 1 and 2 disclose that a blood slip-imparting agent is applied to a top sheet (surface sheet). According to the disclosure of Patent Documents 1 and 2, the blood slippering agent is a substance that comes into contact with the menstrual blood that has reached the top sheet and slides down into the recess together with the menstrual blood.

Japanese Patent No. 5717685 Japanese Patent No. 5998000

Patent Document 1 describes the absorbency of preventing menstrual blood from diffusing out of the excretion opening contact area by applying the blood slippering agent and forming a predetermined embossing surrounding the excretion port contact area. The article is listed. Further, Patent Document 2 describes a non-woven fabric that suppresses diffusion in the lateral direction (plane direction) by applying a blood slip-imparting agent and having a structure having ridges, grooves, and through holes.

However, there is a need for a configuration in which the function of suppressing the diffusion of the body fluid in the surface direction of the surface sheet is further improved, and the diffusion of the body fluid in the surface direction can be kept in a narrower range.

In view of the above points, one embodiment of the present invention suppresses the diffusion of the body fluid in the surface sheet, thereby limiting the diffusion of the body fluid in the surface direction to a narrower range and causing the body fluid to come into contact with the skin. An object of the present invention is to provide an absorbent article capable of reducing pleasure and the like.

The first embodiment of the present invention includes an absorption body including a liquid-permeable front surface sheet, a liquid-impermeable back surface sheet, and an absorber provided between the front surface sheet and the back surface sheet. It is a sex article, and the main body extends around the first region including the center of the region corresponding to the body fluid discharge port of the wearer at the time of wearing and the area of the first region, and is larger than the area of the first region. It has a second region having an area, and hydrophobic particles are coated on at least the surfaces of the first region and the second region, and the hydrophobic particles per unit area coated on the first region. The amount is less than the amount of the hydrophobic particles per unit area applied to the second region.

According to the first aspect, the hydrophobic particles are coated on the surface of the surface sheet. Since the hydrophobic particles have relatively low wettability to the body fluid, when the body fluid is discharged onto the surface sheet and comes into contact with the hydrophobic particles, the body fluid is unlikely to move from that position. Therefore, the movement of body fluid on the surface sheet can be suppressed. As a result, the range in which the body fluid diffuses in the surface direction can be reduced, and the tactile discomfort caused by the body fluid coming into contact with the skin can be reduced. In addition, it is possible to reduce the discomfort (visual discomfort) caused by the appearance of the body fluid spreading on the surface sheet during use.

However, if the effect of suppressing the diffusion of body fluids by such hydrophobic particles is large, the absorption rate from the surface sheet to the absorber tends to decrease. On the other hand, in the above embodiment, the amount of hydrophobic particles per unit area existing in the first region including the center of the region corresponding to the body fluid discharge port is present in the second region extending around the first region. It is less than the amount of hydrophobic particles per unit area. This allows the body fluid to be transferred to the absorber relatively quickly in the first region where most of the drained body fluid can reach first. Therefore, the body fluid is less likely to remain on the first region, and the discomfort caused by the body fluid adhering to the skin in the vicinity of the body fluid discharge port can be reduced.

In the second embodiment of the present invention, the amount of the hydrophobic particles applied to the second region is 20 to 100 g / m 2, and the amount of the hydrophobic particles applied to the first region is 10 g / ^{m 2.} It is m ² or less.

According to the second aspect, since the range of the amount of hydrophobic particles per unit area in the second region is defined, the effect of being able to satisfactorily suppress the diffusion of body fluid in the surface direction in the second region. It is possible to avoid inconveniences such as the amount of hydrophobic particles becoming excessively large and the porosity of the surface sheet being blocked while maintaining the above. Further, since the amount of hydrophobic particles per unit area in the first region is set to a predetermined value or less, the above-mentioned effect that the body fluid can be more quickly absorbed from the surface sheet to the absorber in the first region is improved. Can be made to.

In the third embodiment of the present invention, the first region is not coated with hydrophobic particles.

According to the third embodiment, since the hydrophobic particles are not applied to the first region, the absorption of the body fluid from the surface sheet to the absorber is further performed in the first region where most of the body fluid reaches first. It will be prompt. This makes it possible to reduce the discomfort felt in the vicinity of the body fluid discharge port. This embodiment in which the hydrophobic particles are not applied to the first region can be suitably used especially when the amount of body fluid is large.

In the fourth aspect of the present invention, the area of the first region is 75 to 1300 mm ² .

According to the fourth aspect, the area of the first region has a predetermined size, and the region where the absorption from the surface sheet to the absorber proceeds relatively quickly has an appropriate area. .. As a result, while maintaining the effect of the hydrophobic particles of keeping the area where the body fluid diffuses in a small range, the body fluid discharged from the body fluid discharge port is transferred from the surface sheet to the absorber in the vicinity of the area corresponding to the body fluid discharge port. It becomes possible to absorb more reliably.

In the fifth aspect of the present invention, the center of the shape of the first region coincides with the center of the region corresponding to the body fluid discharge port.

According to the fifth embodiment, since the center of the shape of the first region and the center of the region corresponding to the body fluid discharge port coincide with each other, the first region is set to the region corresponding to the body fluid discharge port and its vicinity. It can be surely corresponded. As a result, the body fluid discharged from the body fluid discharge port can be more reliably absorbed from the surface sheet to the absorber in the first region.

In the sixth embodiment of the present invention, the shape of the first region is a line-symmetric polygon, a circle, or an ellipse with the center line in the anteroposterior direction of the absorbent article as a symmetric line.

According to the sixth aspect, since the first region has a predetermined shape, the first region can be a region having a predetermined spread in all directions. As a result, in the first region, the surface sheet can be more reliably absorbed into the absorber.

A seventh aspect of the present invention comprises a main body having a liquid-permeable front surface sheet, a liquid-impermeable back surface sheet, and an absorber provided between the front surface sheet and the back surface sheet. A method for manufacturing an absorbent article, wherein the main body has a first region including a center of a region corresponding to a body fluid discharge port of a wearer at the time of wearing, and a second region extending around the first region. The amount of the hydrophobic particles per unit area applied to the first region includes the step of applying the hydrophobic particles to the surface of the surface sheet, and the amount of the hydrophobic particles per unit area applied to the second region is the amount of the hydrophobic particles applied to the second region. Less than the amount.

According to the seventh embodiment, it is possible to provide a method for producing an absorbent article having the same effect as that of the first embodiment.

According to one embodiment of the present invention, by suppressing the diffusion of the body fluid on the surface sheet, the diffusion of the body fluid in the surface direction can be kept in a narrower range, and the discomfort caused by the body fluid coming into contact with the skin can be reduced. Absorbent articles can be provided.

It is a partially cutaway plan view for demonstrating the basic structure of the absorbent article by one embodiment of this invention. FIG. 5 is a cross-sectional view taken along the line I-I of an absorbent article according to an embodiment of the present invention. It is a top view of the absorbent article by one embodiment of this invention. It is a top view of the absorbent article by one embodiment of this invention. It is a figure for demonstrating the sample used in an Example. It is a figure for demonstrating the apparatus used in the absorption test in an Example.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows a partially broken view of a sanitary napkin as an example of an absorbent article according to one embodiment of the present invention. Further, FIG. 2 shows a cross section taken along line I-I of FIG. As shown in FIGS. 1 and 2, the absorbent article 1 includes a liquid-impermeable back sheet 2, a liquid-permeable front sheet 3, and an absorber 4 provided between the two sheets 2 and 3. It is provided with a main body (absorbent article main body) 8 to have. In order to maintain the shape of the absorber 4, the absorber 4 may be wrapped with an encapsulating sheet 5 made of crepe paper, a non-woven fabric, or the like.

As shown in FIG. 1, the main body 8 has an elongated shape having a predetermined length in the front-rear direction and a predetermined width in a direction orthogonal to the front-rear direction as a whole. The width of the main body 8 is substantially constant in the illustrated example, but may vary in the front-rear direction. The absorbent article (sanitary napkin) 1 can have a shape substantially axisymmetric with respect to the center line (front-back direction center line or longitudinal direction center line) CL extending in the front-rear direction.

Further, the absorbent article main body 8 has a region (area corresponding to the body fluid discharge port) 50 corresponding to the body fluid discharge port including the wearer's vaginal opening, labia minora, etc. at the time of wearing, and the body fluid discharge port corresponding area 50 is It has a center 50A. The center 50A is located on the center line CL in the anteroposterior direction, and is located at the center of the length in the anteroposterior direction of the region 50 corresponding to the body fluid discharge port. The main body 8 has a central region RM including a body fluid discharge port corresponding region 50, a front region RF in front of the central region RM, and a rear region RR behind the central region RM.

The central region RM may have wings W, W extending from both sides thereof to securely secure the absorbent article 1 to the underwear when it is attached. The front region RF is the region from the starting point in front of the wings W and W to the front end edge of the main body 8, and the rear region RR is the rear end of the main body 8 from the starting point behind the wings W and W. It can be an area up to the edge. When the wings W and W are provided, the center 50A of the body fluid discharge port corresponding region 50 is located at the midpoint of the length of the lateral edge of the wings W and W in the front-rear direction when viewed in the front-rear direction. It can be, or it can be located in the middle of the front and rear edges of the wings W, W.

In the examples of FIGS. 1 and 2, the absorbent article 1 has wings W and W, but the absorbent article 1 can be in a form without wings W and W. In that case, when the wings W and W are formed at the positions where the wings W and W are conventionally formed, the region in front of the starting point of the wings W and W is set as the front region RF, and the region behind the wings W and W is set as the front region RF. The region rearward from the position serving as the starting point of the above can be defined as the rear region RR. The length of the central region RM in the anteroposterior direction can be 50 to 90 mm.

On the peripheral edge of the main body 8, the outer edge of the back surface sheet 2 and the outer edge of the front surface sheet 3 may be joined by an adhesive such as hot melt or an adhesive means such as heat seal or ultrasonic seal. Further, side non-woven fabrics 7 may be provided on both sides of the surface sheet 3 side along the front-rear direction (longitudinal direction), respectively. The side non-woven fabric 7 partially protrudes to the side of the main body 8 and is laminated on the back surface sheet 2 which also protrudes to the side, and is joined by an adhesive such as hot melt or an adhesive means such as heat seal or ultrasonic seal. As a result, the above-mentioned wings W and W are formed on both sides of the main body 8.

As the back sheet 2, a sheet material having at least water impermeability, such as an olefin resin sheet such as polyethylene or polypropylene, can be used. It is possible to use a laminated non-woven fabric in which a non-woven fabric is laminated on a polyethylene sheet or the like, or a laminated non-woven fabric sheet in which a waterproof film is interposed to ensure substantially impermeable liquid. Further, from the viewpoint of preventing stuffiness, it is more desirable to use a material having moisture permeability. Such a water-impervious / moisture-permeable sheet material is obtained by melting and kneading an inorganic filler in an olefin resin such as polyethylene or polypropylene to form a sheet, and then stretching the sheet in the uniaxial or biaxial direction. A porous sheet can be used.

The surface sheet 3 is a liquid-permeable sheet that rapidly permeates body fluids such as menstrual blood, vaginal discharge, and urine. As the surface sheet 3, a perforated or non-perforated non-woven fabric, a porous plastic sheet, or the like is preferably used. As the material fibers constituting the non-woven fabric, for example, olefins such as polyethylene and polypropylene, synthetic fibers such as polyester and polyamide, recycled fibers such as rayon and cupra, blended fibers thereof, and natural fibers such as cotton can be used alone or. Two or more types can be used in combination. Examples of the non-woven fabric processing method include a spunlace method, a spunbond method, a thermal bond method, a melt blown method, and a needle punch method. Of these processing methods, the spunlace method is preferable in that it can produce a flexible non-woven fabric and the spunbond method is preferable in that it can produce a drapeable non-woven fabric, and the thermal bond method is preferable in that it can produce a bulky and soft non-woven fabric. Further, composite fibers such as core-sheath type fibers having a high melting point fiber as a core and a low melting point fiber as a sheath, side-by-side type fibers, and split type fibers can be used.

The surface sheet 3 may be perforated as described above, and may have a plurality of openings 20 as shown in FIG. 1, for example. The opening 20 is a through hole that penetrates from one side of the surface sheet 3 to the other side. The opening 20 may be, for example, a circle having a diameter of 0.5 to 2.0 mm, or another shape such as an ellipse or a quadrangle having an area equivalent to the circle. Further, the pitch between the openings 20 can be 5 to 15 mm. By providing such an opening 20 in the surface sheet 3, even if a highly viscous body fluid is discharged onto the surface sheet 3, such a body fluid can be permeated through the surface sheet 3 more quickly. Can be done. Therefore, the opening 20 contributes to the above-mentioned effect of suppressing the diffusion of the body fluid in the surface sheet 3 in the surface direction.

In the illustrated example, the openings 20 are formed over the entire surface sheet 3, but the openings 20 are formed in a part of the surface sheet 3, for example, the body fluid discharge port corresponding region 50 or the central region RM. It is also possible to form a form that is not formed in a region other than the above. Further, the size and / or pitch of the opening 20 in the body fluid discharge port corresponding region 50 and the central region RM can be made different from the size and / or pitch of the opening 20 in other regions.

Further, as shown in FIG. 1, a dot-shaped pressing portion (emboss) 30 may be formed on the surface sheet 3 over the entire surface sheet 3. The dot-shaped pressing portion 30 may be formed between the openings 20, and as shown in the illustrated example, the region surrounded by the opening 20 and the dot-shaped pressing portion 30 has a quadrangle such as a square. You may be.

The absorber 4 interposed between the back surface sheet 2 and the front surface sheet 3 is not limited as long as it is a material capable of absorbing and retaining body fluid, but preferably contains cotton-like pulp and a water-absorbent polymer. As the water-absorbent polymer, a superabsorbent polymer (SAP), a superabsorbent polymer fiber (SAF), or a combination thereof can be used. Examples of the pulp include chemical pulp obtained from wood, cellulose fibers such as dissolving pulp, and artificial cellulose fibers such as rayon and acetate. As a raw material for chemical pulp, softwood, softwood and the like are used, but softwood is preferably used because of its long fiber length and the like.

Further, synthetic fibers may be mixed with the absorber 4. As the synthetic fiber, polyolefins such as polyethylene and polypropylene, polyesters such as polyethylene terephthalate and polybutylene terephthalate, polyamides such as nylon, and copolymers thereof can be used, and two of these can be mixed. It can also be used. Further, composite fibers such as core-sheath type fibers having a high melting point fiber as a core and a low melting point fiber as a sheath, side-by-side type fibers, and split type fibers can also be used. It is also possible to use a hydrophobic fiber whose surface is treated with a hydrophilic agent to give it an affinity for body fluids.

The thickness of the absorber 4 can be in the range of 0.5 to 25 mm, preferably in the range of 1.5 to 6.5 mm. The absorber 4 does not have to have a uniform thickness over the front surface, and may have a structure in which the body fluid discharge port corresponding region 50 and the region in the vicinity thereof, and the central portion in the width direction of the rear region RR are bulged. .. Further, the absorber 4 is preferably manufactured by a stacking fiber or an airlaid method.

As the side non-woven fabric 7, a water-repellent treated non-woven fabric or a hydrophilic treated non-woven fabric can be used. For example, in the case of enhancing the effect of preventing menstrual blood or vaginal discharge from penetrating or enhancing the feeling of touch, it is preferable to use a water-repellent treated non-woven fabric coated with a silicone-based, paraffin-based, alkylchromic chloride-based water repellent or the like. .. Further, in the case of enhancing the absorbability of menstrual blood and the like in the wings W and W, it is preferable to use a hydrophilically treated non-woven fabric as the material of the non-woven fabric. As the type of non-woven fabric, a soft air-through non-woven fabric that does not easily crease and wrinkle is preferable.

On the outer edges of the wings W and W, squeezing portions (embossing) having a dot shape or a predetermined shape are provided at predetermined positions for the purpose of joining the side non-woven fabric 7 and the back surface sheet 2 and increasing the rigidity. You may.

The total length of the absorbent article 1 can be 130 to 450 mm, preferably 140 to 360 mm.

In one embodiment of the present invention, as shown in FIG. 3, the main body 8 extends around the first region A including the center 50A of the wearer's body fluid discharge port corresponding region 50 and the circumference of the first region A when worn. , A unit having a second region B (shown in gray) having an area larger than the area of the first region A, hydrophobic particles coated on the surface of the surface sheet 3, and coated on the first region A. The amount of hydrophobic particles per area is less than the amount of hydrophobic particles per unit area applied to the second region B, which is an absorbent article.

Since the surface sheet 3 is liquid permeable, when the body fluid is discharged onto the surface sheet 3, the body fluid can be transferred to the absorber provided under the surface sheet 3 through the surface sheet 3. At this time, in the conventional absorbent article, the body fluid can diffuse on the surface sheet 3 in the surface direction, and a part of the body fluid can diffuse in the surface sheet 3, although it depends on the amount and viscosity of the body fluid. The body fluid diffused on the surface sheet 3 may come into contact with the skin and cause discomfort such as stickiness.

On the other hand, in this embodiment, the hydrophobic particles are applied to a predetermined area on the surface sheet side of the absorbent article. Here, the state in which the hydrophobic particles are applied means that the hydrophobic particles are present on the surface of the surface sheet 3 by applying the hydrophobic particles to the surface of the surface sheet 3, and in some cases, the surface sheet 3 is coated. It is in a state where it also exists inside. When the surface sheet 3 is made of a non-woven fabric, hydrophobic particles are attached to the surface of the fibers of the non-woven fabric.

Since the wettability of the hydrophobic particles to the body fluid is small, when the body fluid discharged on the surface sheet 3 comes into contact with the hydrophobic particles existing on the surface sheet 3 and / or in the surface sheet 3, the body fluid spreads from the place. It becomes difficult. Therefore, in the surface sheet 3 coated with the hydrophobic particles, as compared with the surface sheet not coated with the hydrophobic particles, in the surface sheet 3, that is, on the surface sheet 3 and / or in the surface sheet 3. , Diffusion of body fluid is suppressed. As a result, the area in which the body fluid spreads on the surface sheet 3 in a plan view can be reduced, and the tactile discomfort caused by the body fluid coming into contact with the skin in a wide range can be reduced. In addition, it is possible to reduce the visual discomfort caused by the appearance of the body fluid spreading on the surface sheet 3 during use.

However, if the effect of suppressing the diffusion of body fluid as described above is large, the absorption rate from the surface sheet 3 to the absorber 4 tends to decrease. On the other hand, in the present embodiment, the amount of hydrophobic particles per unit area contained in the first region A including the center A of the body fluid discharge port corresponding region 50 is the amount of hydrophobic particles per unit area contained in the second region B. It is less than the amount of sex particles. Therefore, the body fluid can be transferred relatively quickly in the first region A where most of the discharged body fluid can reach first. Therefore, in the first region A, the body fluid from the surface sheet 3 to the absorber 4 can be transferred. Can be absorbed relatively quickly. Therefore, the body fluid is less likely to remain on the first region A, and the discomfort caused by the body fluid adhering to the skin in the vicinity of the body fluid discharge port can be reduced. Further, since rapid absorption is performed in the first region A, the amount of body fluid spreading to the surroundings can be reduced, and even when the amount of body fluid is relatively large, diffusion of the body fluid in the surface direction can be suppressed.

Further, when the body fluid is absorbed from the surface sheet 3 to the absorber 4 in the first region A, it can also diffuse into the second region B in the absorber 4. Here, a phenomenon in which the body fluid once absorbed by the absorbers 4 in the first region A and the second region B is returned to the surface by the skin being pressed against the main body 8 at the time of wearing, that is, so-called reversion may occur. , May cause discomfort. In this embodiment, such reversion of body fluid can be made substantially the same as that of the conventional product.

The area of the second region B can be larger than the area of the first region A. By increasing the area of the second region B in which the amount of the hydrophobic particles applied is large, it is possible to more effectively prevent the body fluid from spreading and diffusing from the region 50 corresponding to the body fluid discharge port to the surroundings. Further, the second region B may be the entire region excluding the first region A from the region where the surface sheet 3 is exposed, or the first region A is excluded from the central region RM as shown in the illustrated example. It may be a region or a region obtained by excluding the first region A from at least a part of the central region RM and the anterior region RF and the rear region RR adjacent thereto. It is economically advantageous to provide a region where particles are not applied to the front or rear end of the absorbent article 1.

The hydrophobic particles may be inorganic particles or organic particles having a hydrophobic surface. Examples of the inorganic particles include talc, bentonite, kaolin, mica, sericite, silica, zinc oxide, titanium oxide, calcium carbonate and the like. Examples of the organic particles include nylon, acrylic resin, silicone, polyolefin, polystyrene, polyurethane, polyester and the like. The organic particles may be a polymer alloy, a copolymer, or the like. These particles can be used alone or in combination of two or more. Of the above particles, inorganic particles are preferable, and talc is preferably used because it has an appropriate hydrophobicity.

Further, the surface of a predetermined particle is hydrophobized by a silylation treatment or the like to obtain a particle having or improved hydrophobicity, which can be used as the hydrophobic particle in the present embodiment. The above particles that have been hydrophobized can also be used as the hydrophobic particles in this embodiment.

The color of the hydrophobic particles is not particularly limited, but white ones are preferable. By using the white particles, the body fluid absorbed in the surface sheet 3 or the absorber 4 becomes difficult to see, and the visual discomfort can be further reduced. Further, since the surface sheet 3 is often white or a light color close to white, if the particles are white, the absorbent article 1 will not be noticeable even if it is applied, and will not cause discomfort in appearance. Can be used.

The average particle size of the hydrophobic particles is preferably 100 μm or less. When the average particle size is in this range, the applied particles are likely to adhere to the fibers of the surface sheet, and the above-mentioned effect of suppressing the diffusion of body fluid is likely to be exerted. The average particle size of the hydrophobic particles is more preferably 1 to 80 μm, further preferably 3 to 50 μm, and even more preferably 5 to 20 μm. By setting the above range, it is possible to improve the action of suppressing the diffusion of body fluids and to make it difficult to feel the roughness of particles. _{The average particle size in the present specification is a medium diameter (D 50} ) calculated from a volume-based particle size distribution measured by a laser diffraction / scattering method.

Preferably the amount of hydrophobic particles applied to the second region B is 20 to 100 g / ^{m 2,} more preferable to be 30~90g / ^{m 2,} further preferably a 40~70g / ^{m 2.} By setting the amount of the hydrophobic particles applied to the second region B to 20 g / m ² or more, the diffusion of the body fluid on the surface sheet can be suppressed more satisfactorily. Further, by setting the amount of the hydrophobic particles applied to the second region B to 100 g / m ² , the particles are excessively applied on the surface sheet 3, and the porosity formed on the surface sheet 3, that is, the above-mentioned It is possible to avoid blocking the openings 20 and the gaps between the fibers to prevent the flow of body fluid in the thickness direction of the absorbent article.

The amount of hydrophobic particles applied to the first region A is preferably 0 to ^{10 g / m 2 or less.} In the form in which hydrophobic particles of 10 g / m ² or less are present in the first region A, the diffusion of the body fluid in the first region A can be satisfactorily suppressed, and therefore, particularly when the amount of the discharged body fluid is relatively small. Is preferable.

The amount of hydrophobic particles applied to the first region A ^{can be as small as 5 g / m 2} or less, in which case ^{it is more preferably 1 g / m 2} or less, and 0.1 g / m ² or less. Is more preferable. Further, it is more preferable that the first region A is not coated with hydrophobic particles. When the amount of the discharged body fluid is relatively large, the body fluid is more likely to remain on the surface sheet 3. Therefore, the amount of the hydrophobic particles applied to the first region A is set as the above range, and the surface sheet in the first region A is set. By increasing the absorption rate of the body fluid from 3 to the absorber 4, the discomfort caused by the remaining body fluid can be reduced. Therefore, the form in which the hydrophobic particles are not applied to the first region A can be suitably used as an absorbent article used especially when the amount of body fluid discharged or the discharge rate is large.

Difference between the amount of hydrophobic particles applied to the second region B and the amount of hydrophobic particles applied to the first region A ((the amount of hydrophobic particles applied to the second region B per unit area) -(Amount of hydrophobic particles per unit area applied to the first region A) is ^{preferably 10 g / m 2} or more, more preferably 20 g / m ² or more, and 30 g / m ² or more. It is more preferable to have it, and it is further preferable to have 50 g / m ^{2 or more.} By setting the above range, it becomes difficult for the body fluid to migrate from the first region A to the second region B at the boundary between the first region A and the second region B, so that the surface in the first region A The absorption from the sheet 3 to the absorber can be further promoted, and the diffusion of the body fluid in the surface direction on the surface sheet 3 can be further suppressed.

More area of the first region A is appropriately determined depending on the size and application of the absorbent article 1, preferable to be 75～1300Mm ^2, more preferable to be 100～1200Mm ^2, When it is 200 to 1000 mm ² It is preferably 250 to 750 mm ² , and more preferably 250 to 750 mm 2. By setting the area of the first region A to 75 mm ² or more, it is possible to secure an appropriate area in which the transfer of the body fluid from the surface sheet 3 to the absorber 4 proceeds rapidly. As a result, most of the body fluid can be absorbed in the first region A, and the amount of body fluid diffused from the first region A to the surroundings can be reduced. Further, by setting the area of the first region A to 1300 mm ² or less, it is possible to reduce the range in which the body fluid is likely to diffuse in the surface direction.

As shown in FIG. 3, it is preferable that the center of the shape of the first region A and the center 50A of the region 50 corresponding to the body fluid discharge port coincide with each other. When the center of the shape of the first region A coincides with the center 50A of the region 50 corresponding to the body fluid discharge port, the body fluid discharged from the body fluid discharge port can be more reliably absorbed in the first region A. Further, the center of the shape of the first region A and the center 50A of the region 50 corresponding to the body fluid discharge port may be separated from each other with a distance of 10 mm or less in the front-rear direction.

The center 50A of the region 50 corresponding to the body fluid discharge port may be located 70 to 100 mm from the front end of the main body 8. Further, in the center 50A, when a pair of anteroposterior squeezing grooves 14 and 14 are provided on both sides of the body fluid discharge port corresponding region 50 as shown in FIGS. 1 and 3, the pair of anteroposterior squeezing grooves It may be in the center position in the front-back direction.

The shape of the first region A is not particularly limited, but it is preferably a line-symmetrical shape with the anteroposterior center line CL of the absorbent article 1 as a symmetric line, and more preferably a point-symmetrical shape. For example, it can be a polygon such as a quadrangle such as a square, a rectangle, or a rhombus, a circle, or an ellipse. Since the first region A has such a shape, a predetermined area can be secured in all directions, and in the first region A, the body fluid is more reliably transferred from the surface sheet 3 to the absorber 4. Can be absorbed. Further, the shape of the first region A is preferably long in the front-rear direction in view of the shape of the liquid discharge port, particularly when the absorbent article 1 is a sanitary napkin.

The amount of hydrophobic particles per unit in the first region A and the second region B may or may not be uniform in each region. It is also possible to divide each region into a plurality of divisions and make the amount of hydrophobic particles per unit area different for each division. For example, in at least one of the first region A and the second region B, striped divisions in the anteroposterior direction or the width direction are formed, and divisions in which the amount of hydrophobic particles is relatively small and divisions in which the amount of hydrophobic particles is relatively large are alternately arranged. You can also.

In the above-described embodiment, the main body 8 has a first region A and a second region B, and the amount of hydrophobic particles applied in each region is different, but the main body 8 has three or more regions. , The amount of hydrophobic particles applied can also be different from each other in each region. For example, an annular third region C that surrounds the first region A is provided between the first region A and the second region B, and the amount of hydrophobic particles applied to the third region C is determined. It can be larger than the amount of hydrophobic particles in the first region A and smaller than the amount of hydrophobic particles in the second region B. Similarly, two or more regions may be formed between the first region A and the second region B, and the amount of hydrophobic particles to be applied may be changed stepwise.

As shown in FIGS. 1 and 2, the main body 8 of the absorbent article 1 may have a squeezing groove (emboss) formed by squeezing the surface sheet 3 and the absorbent body 4. As such a squeezing groove, it is preferable that a pair of front-rear squeezing grooves 14 and 14 extending in the front-rear direction are provided at least along the side of the body fluid discharge port corresponding region 50 of the central region RM. The central region RM can be easily bent laterally along the front-rear squeezing grooves 14 and 14 when worn, and has a function of raising the central portion of the central region RM in the width direction toward the body to improve the fit. It also has the function of suppressing the lateral diffusion of body fluids. Further, as shown in FIG. 1, anterior squeezing groove 12 in the anterior region RF, posterior, in order to suppress the transfer of body fluid to the end and / or to allow deformation of the body 8 along the shape of the body. A rear squeeze groove 16 may be formed in the region RR.

Further, the main body 8 of the absorbent article 1 may be formed with a blocking squeezing groove 18 as shown in FIG. The blocking and squeezing groove 18 can be formed in at least one of the anterior and posterior of the first region A, and is preferably formed in both anterior and posterior as in the illustrated example. The blocking and squeezing groove 18 can effectively suppress the leakage of body fluid from the first region A forward and / or backward. In particular, even when body fluid remains on the surface of the surface sheet 3 in the second region B, it is possible to prevent such body fluid from flowing and leaking.

In the illustrated example, the blocking and squeezing groove 18 has a substantially V-shape whose tip portion faces toward the body fluid discharge port corresponding region 50, but may have a different shape. For example, the blocking squeezing groove 18 may have a shape that extends in the width direction in a straight line or in a curved shape. Further, it is preferable that the blocking squeezing groove 18 is formed in the front end and / or the rear end of the front-rear squeezing grooves 12 and 12 and the region in the vicinity thereof.

One embodiment of the present invention is a method for producing an absorbent article, specifically, between a liquid-permeable front surface sheet 3, a liquid-impermeable back surface sheet 2, and a front surface sheet 3 and a back surface sheet 2. An absorbent article 1 including a main body 8 having an absorber 4 provided in the above, wherein the main body 8 includes a first region A including a center of a region corresponding to a body fluid discharge port of a wearer at the time of wearing. A method for producing an absorbent article 1 having a second region B extending around a first region A, which comprises a step of applying hydrophobic particles to the surface of the surface sheet 3 and is applied to the first region A. The amount of hydrophobic particles to be applied per unit area is smaller than the amount of hydrophobic particles to be applied to the second region B, which is a production method.

The coating method in the step of coating the hydrophobic particles on the surface of the surface sheet 3 is not particularly limited, and a known coating means can be used. For example, hydrophobic particles can be dispersed in a liquid medium to prepare a dispersion, and the dispersion can be printed on a desired region of the main body 8 using a known printing means. As the medium, a volatile medium may be used, or a non-volatile medium that promotes the bond between the surface sheet 3 and the hydrophobic particles after coating may be used. Examples of the printing means include flexographic printing and gravure printing. When the hydrophobic particles are dispersed in a liquid to prepare a dispersion liquid, a resin or the like may be contained in addition to the particles and the medium.

Alternatively, as another coating method, a sprayer can be used to spray the dispersion liquid onto a desired region. Further, the hydrophobic particles can be sprayed together with air using a fluid nozzle, or can be applied using an electrostatic coating device.

The above-mentioned form was a sanitary napkin, but the absorbent article according to this form can be used not only as a sanitary napkin but also as a panty liner, an incontinence pad, a diaper and the like. The position and size of the area corresponding to the body fluid discharge port can be appropriately determined according to each application.

Hereinafter, the present invention will be described in more detail by presenting Examples and Comparative Examples, but the present invention is not limited to the Examples.

[Preparation of sample]
(Example 1)
An absorbent article (sanitary napkin) having a total length of 21 cm having the same structure as the absorbent article shown in FIG. 1 was prepared. A baby powder (manufactured by Pigeon Corporation, "Medicated Baby Powder J") is applied to the coating area B (FIG. 5A) of the absorbent article using a puff, and the coating amount per unit area is 58.8 g /. It was applied uniformly so as to be ^{m 2.} In the first embodiment, the region B is a region colored in gray as shown in FIG. 5A, and is the center of the region corresponding to the body fluid discharge port from the region where the surface sheet is exposed in the central region RM of the main body. Area excluding the area (first area) A including the above. In this embodiment, the region A is a circular region having a diameter of 1 cm, and the area of the region A is 79 mm ² . In addition, the center of the area A coincided with the center of the area corresponding to the body fluid discharge port. The coating amount of the particles was determined by measuring the weight of the absorbent article before and after coating and dividing the difference in weight by the coating area.

(Example 2)
A sample was prepared in the same manner as in Example 1 except that the diameter of the circular shape of the region A was 2 cm and the area was 314 mm ^2.

(Example 3)
A sample was prepared in the same manner as in Example 1 except that the diameter of the circular shape of the region A was 3 cm and the area was 707 mm ^2.

(Example 4)
A sample was prepared in the same manner as in Example 1 except that the diameter of the circular shape of the region A was 4 cm and the area was 1256 mm ^2.

(Example 5)
It was produced in the same manner as in Example 3 except that a V-shaped blocking and pressing groove as shown in FIG. 5B was formed in front of and behind the body fluid discharge port corresponding region of the absorbent article, respectively.

(Comparative Example 1)
The absorbent article before applying the baby powder in Example 1 was used as a sample (FIG. 5 (c)).

(Comparative Example 2)
A sample was prepared in the same manner as in Example 1 except that the area to which the baby powder was applied was the entire surface of the area where the surface sheet of the main body was exposed (FIG. 5 (d)).

[Test method]
<Absorption rate test>
An absorption rate test was performed using a predetermined instrument 60. A general perspective view and a plan view of the predetermined instrument 60 are shown in FIGS. 6 (a) and 6 (b), respectively. The instrument 60 has a structure in which a recess 62 is provided in the center and a through hole 64 is provided in the bottom surface thereof. The through holes 64 on the bottom surface of the instrument 60 had the shape of three through slits intersecting each other at the center of the bottom surface, and the length of each slit was 23 mm. The device was placed on a sanitary napkin so that the center of the area corresponding to the body fluid discharge port coincided with the center of the device. 1 cc of artificial menstrual blood at 37 ° C. was injected through the instrument 60, and the time until the artificial menstrual blood permeated (the time until the artificial menstrual blood disappeared from the surface sheet) was measured. After the first absorption was completed, the sample was allowed to stand for 3 minutes, and then 1 cc of artificial menstrual blood was injected again in the same manner as in the first absorption, and the time until the artificial menstrual blood soaked was measured and used as the absorption time.

<Diffusion test>
The sample subjected to the above absorption rate test was visually observed, and the length of the artificial menstrual blood portion diffused on the surface sheet in the anteroposterior direction and the width direction was measured and used as the diffusion length. The diffusion length was set to the longest length in each of the front-rear direction and the width direction. In this observation, the artificial menstrual blood absorbed and diffused by the absorber through the surface sheet can also be seen through, but the diffusion in such an absorber is not included in the diffusion length.

<Reverse amount test>
After performing the above absorption rate test, the sample was allowed to stand for 1 minute. Then, a filter paper having a size covering the central region RM was placed, and a weight was further placed on the filter paper ^{to apply a load of 5 g / m 2} , and the amount of artificial menstrual blood absorbed by the filter paper was measured.

<Liquid flow test>
The sample was placed on a 30 ° inclined surface (a surface having an inclination of 30 ° with respect to the horizontal direction) so that the surface sheet side was facing up. At that time, the sanitary napkin was placed so that the front-rear direction was the same as the inclination direction and the front was at a higher position. Using a fixed burette, 1 cc of artificial menstrual blood was dropped from 1.0 cm above toward the center of the area corresponding to the body fluid discharge port of the sample. At that time, the cock of the burette was squeezed until the artificial menstrual blood was continuously dropped from the burette drop by drop, and the dropping was performed.

The droplets dropped on the surface sheet are either immediately absorbed at that position, or are not absorbed or sufficiently absorbed at that position, and flow down on the surface of the surface sheet toward the rear of the absorbent article. .. The distance that the droplet moved on the surface of the surface sheet when the droplet flowed down was visually measured, and the distance was defined as the liquid flow length. Specifically, the length in the front-rear direction between the position of the rear end of the drop immediately before it is dropped on the surface sheet and begins to flow and the position of the rear end of the drop when the drop has flowed down and stopped flowing is defined as the liquid flow length. bottom. The liquid flow length when the droplet is immediately absorbed at the dropping position is 0 mm.

In this test, the liquid flow length of the first drop of 1 cc of artificial menstrual blood dropped was measured and recorded as the liquid flow length of the first drop. Further, the liquid flow length was measured for the second and subsequent drops and recorded as a liquid flow length of 1 cc. The liquid flow length of 1 cc is such that when a plurality of dropped drops are combined together to form a single flow, the plurality of drops independently flow and fall down the length of the flow. If so, the liquid flow length of the droplet showing the longest liquid flow length was recorded.

After dropping 1 cc as described above, the sample was allowed to stand for 3 minutes, and 1 cc was further dropped. In this way, 1 cc of artificial menstrual blood was dropped repeatedly 5 times in total.

The liquid flow length was evaluated according to the following criteria.
A: 0 mm
B: Over 0 mm to 20 mm
C: Over 20 mm to 40 mm
D: Over 40 mm to 70 mm
E: Over 70 mm to less than 110 mm F: 110 mm (no absorption)

Table 1 shows the results of each of the absorption rate test, the diffusion test, and the reversion amount test, and Table 2 shows the results of the liquid flow test.

From Table 1, in Examples 1 to 4 in which the baby powder was applied to the first region A including the center of the region corresponding to the body fluid discharge port and the second region B around the baby powder was applied, the diffusion distance was such that the baby powder was applied to the surface sheet. It can be seen that the diffusion in the plane direction is well suppressed because it is smaller than that of Comparative Example 1 (conventional product) which is not coated on. In particular, the diffusion distances of Examples 1 to 3 in which the area of the first region A ^{is within the range of 75 to 1000 mm 2} are significantly smaller in both the front-rear direction and the width direction than in Comparative Example 1.

It was also found that the amount of reversion of Examples 1 to 4 was also the same as that of Comparative Example 1 (conventional product). Further, the absorption time of Examples 1 to 4 was not significantly longer than that of Comparative Example 1 (conventional product). In particular, in Examples 2 to 4 in which the area of the first region A ^{falls within the range of 100 to 1300 mm 2} , the absorption time was 1.5 times or less that of Comparative Example 1 (conventional product).

On the other hand, in Comparative Example 2 in which the baby powder was uniformly applied to the entire surface of the central region RM, the diffusion distance was small and the diffusion in the plane direction was suppressed, but the amount of reversion was compared with Examples 1 to 4. It is more than Example 1 (conventional product). Further, the absorption time of Comparative Example 2 was also longer than that of Examples 1 to 4 and Comparative Example 1 (conventional product), and it was found that the absorbability was not sufficient as compared with Examples 1 to 4.

From Table 2, the evaluation of the liquid flow length of the first drop of Examples 1 to 4 was A, which was the same as that of Comparative Example 1 (conventional product). Further, the evaluation of the liquid flow length of 1 cc of Examples 2 to 4 is also equivalent to or higher than that of Comparative Example 1 (conventional product). In Comparative Example 2 in which the baby powder was uniformly applied to the entire surface of the central region RM, the evaluation of the liquid flow length of the first drop and 1 cc was lower than that of Examples 1 to 4.

1 Absorbent article 2 Back sheet 3 Front sheet 4 Absorbent 5 Encapsulated sheet 7 Side non-woven fabric 8 Main body (absorbent article main body)
12 Front squeezing groove 14 Central squeezing groove 16 Rear squeezing groove 18 Blocking squeezing groove 20 Opening 30 Dot-shaped squeezing part (embossing)
50 Area corresponding to the body fluid discharge port 50A Center of the area corresponding to the body fluid discharge port A 1st area B 2nd area CL Front-back direction center line RF Front area RM Central area RR Rear area W Wing

Claims (6)

An absorbent article comprising a main body having a liquid-permeable front surface sheet, a liquid-impermeable back surface sheet, and an absorber provided between the front surface sheet and the back surface sheet.
Wherein the body, the second region having a first region including the center of the region corresponding to the fluid outlet of the wearer when worn, extends around the first region, an area larger than the area of the first region It has a door,
Before SL on the surface of the second region and the hydrophobic particles are applied, the hydrophobic particles are not applied to the first region, the absorbent article. The amount of the hydrophobic particles applied to the second region is 20 to 100 g / m ^2, the absorbent article according to claim 1. The absorbent article according to claim 1 or 2 , wherein the area of the first region is 75 to 1300 mm ^2. The absorbent article according to any one of claims 1 to 3 , wherein the center of the shape of the first region and the center of the region corresponding to the body fluid discharge port coincide with each other. The absorption according to any one of claims 1 to 4 , wherein the shape of the first region is a line-symmetric polygon, a circle, or an ellipse having a center line in the anteroposterior direction of the absorbent article as a symmetric line. Sex goods It includes a main body having a liquid-permeable front surface sheet, an impermeable back surface sheet, and an absorber provided between the front surface sheet and the back surface sheet, and the main body is the body fluid of the wearer when worn. a first region including the center of the region corresponding to the discharge port, and extends around the first region, a manufacturing method of an absorbent article and a second region having an area larger than the area of the first region hand,
The step of applying hydrophobic particles to the surface of the surface sheet is included.
A method for producing an absorbent article, wherein hydrophobic particles are coated on the surface of the second region, and hydrophobic particles are not coated on the first region.

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