JP6754549B2 - Absorbent article - Google Patents

Description

The present invention relates to an absorbent article mainly used for sanitary napkins, vaginal discharge sheets, incontinence pads, toiletries and the like, and has an absorbent structure with enhanced breathability.

Conventionally, as absorbent articles such as panty liners, sanitary napkins, and incontinence pads, impermeable back sheets such as polyethylene sheets or polyethylene sheet laminated non-woven fabrics and liquid-permeable surface sheets such as non-woven fabrics or liquid-permeable plastic sheets have been used. It is known that an absorber made of cotton-like pulp or the like is interposed between the and.

Since such an absorbent article is worn in close contact with the skin, there is a problem that sweat and excrement moisture (moisture) are trapped inside and easily get stuffy. In particular, in a thick absorbent article such as a sanitary napkin for night use, since the absorbent body is thick, hot air and vapor are likely to be trapped inside, and even if a breathable back sheet is used as an impermeable back sheet. In many cases, the effect was not fully exhibited.

Many improvements have been made to this type of absorbent article, and there are various types with improved breathability in order to prevent stuffiness during mounting. For example, in Patent Document 1 below, either the upper layer absorber side or the lower layer absorber side in the region where the upper layer absorber and the lower layer absorber are laminated and face each other and the upper layer absorber exists when viewed in a plan view. An absorbent article is disclosed that comprises a continuous groove on one or both surfaces, the groove reaching the widthwise or longitudinal end of the region in which the upper layer absorber is present.

Further, in Patent Document 2 below, the absorber has a plurality of holes penetrating from the skin contact surface side to the non-skin contact surface side in the central arrangement region, and the plurality of through holes are opened in a plan view. The area is constant from the skin contact surface side to the non-skin contact surface side, and the plurality of through holes have two types of opening areas, large and small, in a plan view of the skin contact surface side. An absorbent article is disclosed in which through-holes having large and small opening areas are formed in the vicinity of each other and are arranged apart from each other.

Japanese Unexamined Patent Publication No. 2013-126457 JP 2011-104059

However, in the absorbent article described in Patent Document 1, although air flows in the plane direction between the upper layer absorber and the lower layer absorber through the groove, air is not released in the thickness direction and the inside is stuffy. The easy situation has not always been sufficiently improved. Further, since the space provided by the groove is provided as an air flow path, when the absorber is crushed by pressure during use, the groove is easily deformed and the air flow rate through the groove is reduced. There was a risk that the internal stuffiness could not be improved.

Further, in the absorbent article described in Patent Document 2, air can flow in the thickness direction of the absorber through the through hole provided in the absorber, but the flow of air in the plane direction is not considered at all.

Therefore, a main object of the present invention is to provide an absorbent article having high air permeability and less stuffiness by causing an air flow in the plane direction and the thickness direction of the absorber so that the moisture inside can be released.

In order to solve the above problems, as the present invention according to claim 1, in an absorbent article in which an absorber is interposed between a liquid-permeable front sheet and a back sheet.
The absorbent body includes a top layer absorbent body arranged on the skin side is composed of a cotton-like pulp and water-absorbing polymer, and a lower absorbent body arranged configured non-skin side by a cotton-like pulp and water absorptive polymer Have and
An intermediate laminate made of a non-woven fabric of thermoplastic fibers which is a synthetic fiber material and has thermal crimpability is interposed between the upper layer absorber and the lower layer absorber, and the intermediate laminate is the upper layer absorber. And has the same planar shape as the lower layer absorber, the peripheral edge of the intermediate layered body is not covered by the upper layer absorber and the lower layer absorber, and the upper layer absorber, the intermediate layered body and the lower layer absorber are formed in the thickness direction. An absorbent article is provided characterized in that it is provided with a plurality of openings through the.

In the invention according to claim 1, the absorber is arranged on the skin side composed of cotton-like pulp and a water-absorbent polymer, and the upper layer absorber is arranged on the non-skin side composed of cotton-like pulp and a water-absorbent polymer. It has a multi-layer structure with a superabsorbent lower layer, and an intermediate laminate made of a non-woven plastic fiber which is a synthetic fiber material and has thermal crimpability is interposed between the upper layer absorber and the lower layer absorber. Therefore, air flows between the fibers of the intermediate laminate, and an air flow occurs in the plane direction between the upper layer absorber and the lower layer absorber. Further, since the intermediate laminate has the same planar shape as the upper layer absorber and the lower layer absorber and the peripheral edge of the intermediate laminate is not covered by the upper layer absorber and the lower layer absorber, the peripheral edge of the intermediate laminate is not covered. It is possible to release air to the outside of the absorber.

Further, since the absorbent article according to the present invention is provided with a plurality of openings penetrating the upper layer absorber, the intermediate laminate, and the lower layer absorber in the thickness direction, the air flow in the thickness direction through the openings. Will occur.

As described above, in the present absorbent article, since the air flow is generated in the plane direction and the thickness direction of the absorber, the moisture inside can be surely released, and the air permeability is high and the stuffiness is hard to be stuffed.

As the present invention according to claim 2, the intermediate laminate is provided with the absorbent article according to claim 1, which has a lower density than the upper layer absorber and the lower layer absorber.

In the invention according to claim 2, by using the intermediate laminate having a density lower than that of the upper layer absorber and the lower layer absorber, air flows between the fibers of the intermediate laminate and the air flows in the plane direction. Is sure to occur.

As the present invention according to claim 3 , the absorbent article according to any one of claims 1 and 2 is provided, wherein the area of the opening is formed at a ratio of 4% to 45% with respect to the area of the absorber. To.

In the invention according to claim 3, in order to secure the air flow rate through the opening, the area of the opening is formed at a predetermined ratio with respect to the area of the absorber.

According to the fourth aspect of the present invention, the embossing of the upper layer absorber to the lower layer absorber by pressing from the skin surface side of the upper layer absorber is formed at a position corresponding to at least the body fluid discharge site and not overlapping the opening. The absorbent article according to any one of claims 1 to 3 provided is provided.

In the invention according to claim 4 , when the fiber density of the intermediate laminate is sparse and the fiber densities of the upper layer absorber and the lower layer absorber have a close relationship, the body fluid is transferred from the upper layer absorber to the lower layer absorber. Since it is difficult and there is a problem that body fluid tends to accumulate in the upper layer absorber, the above is performed by squeezing the upper layer absorber from the skin surface side at least in a region corresponding to the body fluid discharge site and not overlapping the opening. By imparting embossing to the lower layer absorber, the body fluid is easily drawn into the portion densely formed by the embossing by the capillary action, and the transfer of the body fluid from the upper layer absorber to the lower layer absorber is promoted.

As the present invention according to claim 5 , the absorbent article according to claim 4 is provided, wherein the embossed area is formed at a ratio of 1% to 30% with respect to the absorber area.

In the invention according to claim 5 , in order to secure the amount of body fluid transferred from the upper layer absorber to the lower layer absorber, embossing is formed at a predetermined ratio.

As described in detail above, according to the present invention, the air flow occurs in the plane direction and the thickness direction of the absorber, so that the moisture inside can be released, and the air permeability is high and it becomes difficult to get stuffy.

It is a partially broken development view of the sanitary napkin 1 which concerns on this invention. FIG. 2 is a view taken along the line II-II of FIG. FIG. 3 is a view taken along the line III-III of FIG. It is a top view of the absorber 4. It is a VV line arrow view of FIG. 4 showing the flow of air. It is a VV line arrow view of FIG. 4 showing the flow of body fluid.

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

[Basic structure of sanitary napkin 1]
The sanitary napkin 1 includes a non-permeable back sheet 2 made of a polyethylene sheet or the like, a liquid-permeable front sheet 3 that rapidly permeates menstrual blood, vaginal discharge, or the like (hereinafter collectively referred to as body fluid), and these. An absorber 4 made of cotton-like pulp or synthetic pulp interposed between the sheets 2 and 3, and a crepe paper or non-woven fabric surrounding the absorber 4 in order to maintain the shape and improve the diffusivity of the absorber 4. The encapsulating sheet 5 made of the above and the substantially side edge portion of the absorber 4 is provided as an upright base end, and is provided so as to project toward the surface side in a predetermined section in the front-rear direction so as to include at least the blood drainage port portion H. A pair of left and right three-dimensional gather BSs, a non-woven fabric 6 for forming three-dimensional gathers forming the BS, and a side non-woven fabric 7 provided on the outside of the three-dimensional gather BS along the longitudinal direction of the napkin (hereinafter, also referred to as the front-rear direction of the napkin). On the periphery of the absorber 4, the outer edge portion of the impermeable back sheet 2 and the liquid permeable surface sheet 3 is formed of an adhesive such as hot melt, a heat seal, or the like at the upper and lower end edges thereof. The impermeable back sheet 2 and the side non-woven fabric 7 which are joined by a joining means and extend laterally from the absorber 4 at both side edges thereof are formed of an adhesive such as hot melt, a heat seal, or the like. Wing-shaped flaps W and W are formed by the laminated sheet portion formed by the impermeable back sheet 2 and the side non-woven fabric 7 which are joined by the joining means and are located on the vaginal side. the second wing-shaped flaps _W B, is _{W B} are formed in portions.

Hereinafter, the structure of the sanitary napkin 1 will be described in more detail.
As the liquid-impermeable back sheet 2, a sheet material having at least water-shielding property such as polyethylene is used, but it is desirable to use a sheet material having moisture permeability from the viewpoint of preventing stuffiness. The water-impervious / moisture-permeable sheet material has microporous properties obtained by melt-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. Sheets are preferably used. One or more adhesive layers (not shown) are formed along the longitudinal direction of the napkin on the non-skin side surface (outer surface) of the impermeable back sheet 2, and the sanitary napkin 1 is attached to the body when worn. It is designed to be fixed to underwear. As the impermeable back sheet 2, a polylami non-woven fabric in which a plastic film and a non-woven fabric are laminated may be used.

Next, as the liquid-permeable surface sheet 3, a perforated or non-perforated non-woven fabric, a porous plastic sheet, or the like is preferably used. The material fibers constituting the non-woven fabric can be olefin-based fibers such as polyethylene or polypropylene, synthetic fibers such as polyester-based and polyamide-based, recycled fibers such as rayon and cupra, and natural fibers such as cotton. A non-woven fabric obtained by an appropriate processing method such as a method, a spunbond method, a thermal bond method, a melt blown method, or a needle punch method can be used. Among these processing methods, the spunlace method is excellent in that it is rich in flexibility and drapeability, and the thermal bond method is excellent in that it is bulky and has high compression stability. When a large number of through holes are formed in the liquid-permeable surface sheet 3, the body fluid is rapidly absorbed, and the dry touch property is excellent.

The absorber 4 interposed between the impermeable back sheet 2 and the liquid permeable front sheet 3 is composed of, for example, cotton-like pulp and a water-absorbing polymer. The water-absorbent polymer is mixed in the pulp constituting the absorber, for example, as granular powder. Examples of the pulp include cellulose fibers such as chemical pulp and dissolved pulp obtained from wood, and artificial cellulose fibers such as rayon and acetate, and coniferous pulp having a longer fiber length has more functions than broadleaf pulp. It is preferably used in terms of price. In addition, synthetic fibers may be mixed with the absorber 4. As the synthetic fiber, for example, polyolefin-based synthetic fibers such as polyethylene or polypropylene, polyester-based materials such as polyethylene terephthalate and polybutylene terephthalate, polyamide-based materials such as nylon, and copolymers thereof can be used, and these two types can be used. It may be a mixture. 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. In the case of hydrophobic fibers, it is desirable to use the synthetic fibers surface-treated with a hydrophilizing agent so as to have an affinity for body fluids.

The absorber 4 has a two-layer structure including an upper layer absorber 4A arranged on the skin side and a lower layer absorber 4B arranged on the non-skin side. Further, an intermediate laminated body 10 made of a non-woven fabric is interposed between the upper layer absorber 4A and the lower layer absorber 4B. The absorber 4 and the intermediate laminate 10 will be described in detail later.

In the sanitary napkin 1, it is preferable to form a pair of left and right central squeezing grooves 16 from the skin surface side of the liquid permeable surface sheet 3 along a substantially longitudinal direction of the sanitary napkin 1. The central pressing groove 16 may include at least a portion along the substantially longitudinal direction of the napkin on both sides of the longitudinal center line CL, and in the illustrated example, the left and right front end portions and rear end portions are connected to each other. As a whole, the napkin is elongated in the longitudinal direction and closed in the circumferential direction.

Further, the front side squeezing groove 16a having a substantially Ω shape is formed on the front side of the central squeezing groove 16 and separated from the central squeezing groove 16 on the rear side, and the Ω is substantially reversed in the plan view. A posterior squeeze groove 16b in shape is formed. The anterior squeezing groove 16a and the posterior squeezing groove 16b are for capturing the body fluid transmitted to the front side and the rear side of the surface of the sanitary napkin 1, respectively, and surely prevent the body fluid from leaking.

In the illustrated example, the width dimension of the liquid-permeable surface sheet 3 is slightly longer than the width of the absorber 4, as shown in the cross-sectional view of FIG. 2, and only covers the absorber 4. The three-dimensional gather BS is formed of a three-dimensional gather forming non-woven fabric 6 different from the liquid-permeable front sheet 3, and a side non-woven fabric 7 is laminated on the front surface side of the impermeable back sheet 2 on the outside of the three-dimensional gather BS. It is preferable that the structure is as follows. The non-woven fabric 6 and the side non-woven fabric 7 for forming three-dimensional gathers are made of a non-woven fabric material which has been appropriately treated with water repellent or hydrophilic according to the purpose of preventing permeation of body fluids or enhancing the feeling of touch. It is configured. As the non-woven fabrics 6 and 7, those formed from natural fibers, synthetic fibers, recycled fibers and the like by an appropriate processing method can be used, but preferably, the feeling of stiffness is eliminated and stuffiness is prevented. Therefore, it is preferable to use a non-woven fabric having a low basis weight and having air permeability. Specifically, it is desirable to use a non-woven fabric produced with a basis weight of 13 to 23 g / m ² , and in order to reliably prevent the permeation of body fluids, silicon-based, paraffin-based, alkylchromic chloride-based water repellents, etc. A water-repellent treated non-woven fabric coated with is preferably used.

As shown in FIGS. 2 and 3, the side non-woven fabric 7 is adhered with an adhesive such as hot melt over the range up to the outer edge of the impermeable back sheet 2, and is impermeable to the side non-woven fabric 7. the laminated sheet portions of the liquid backsheet 2, a pair of left and right wing flaps W to the absorbent body side portion position substantially corresponding to the body fluid discharge portion, to form a W, which from the second wing-shaped flaps W _B the buttocks side position , to form a _{W B.} These wing-shaped flaps W, W and second wing-shaped flaps W _B, comprising a pressure-sensitive adhesive layer (not shown) respectively on the outer surface side of the W _B, when worn for shorts, the wing-shaped flaps W, folding a W line RL, RL At the position, it is folded back to the opposite side and wrapped around the crotch part of the shorts to stop it.

As the non-woven fabric 6 for forming a three-dimensional gather, a double-folded sheet is used, and at a predetermined position inside the double sheet, both ends or appropriate positions in the longitudinal direction are fixed at a predetermined position in the middle portion in the height direction. The thread-like elastic elastic members 21 ..., 22 ... Are arranged, and as shown in FIG. 2, the pocket P is in an upright state over a predetermined longitudinal range including the blood drainage port H, and has an opening facing inward. , P are formed.
[About the absorber 4 and the intermediate laminate 10]
As described above, the absorber 4 has a two-layer structure including an upper layer absorber 4A arranged on the skin side and a lower layer absorber 4B arranged on the non-skin side. The upper layer absorber 4A and the lower layer absorber 4B have substantially the same planar shape, and in a state where these are laminated, the peripheral edge of the upper layer absorber 4A and the lower layer absorber 4B are shown in FIGS. 1 and 2. It is arranged so that it almost coincides with the periphery of the.

The thickness of the upper layer absorber 4A and the thickness of the lower layer absorber 4B may be the same or different. However, as will be described in detail later, by interposing the intermediate laminate 10 between the upper absorber 4A and the lower absorber 4B, air flows in the plane direction through the intermediate laminate 10 and inside the napkin. Because the upper layer absorber 4A is thicker than the lower layer absorber 4B to generate an air flow in the plane direction at a position away from the skin surface, the upper layer absorber 4A and the lower layer absorber 4B are released. It is preferable to make the upper layer absorber 4A thinner than the lower layer absorber 4B to generate an air flow in the plane direction at a position close to the skin surface from the viewpoint of preventing internal stuffiness. ..

As the upper layer absorber 4A and the lower layer absorber 4B, as described above, for example, those composed of cotton-like pulp and a water-absorbent polymer can be used. The raw materials of the upper layer absorber 4A and the lower layer absorber 4B and their constituent ratios may be the same or different. For example, by increasing the amount of the water-absorbent polymer blended in the lower layer absorber 4B than in the upper layer absorber 4A, more body fluid is retained in the lower layer absorber 4B away from the skin surface, and the absorber can hold more body fluid. The inside may be prevented from getting stuffy due to the absorbed body fluid.

In the sanitary napkin 1, as shown in FIGS. 4 to 6, an intermediate laminated body 10 made of a non-woven fabric is interposed between the upper layer absorber 4A and the lower layer absorber 4B. The laminated body of the upper layer absorber 4A, the intermediate laminated body 10 and the lower layer absorber 4B is surrounded by the enclosed sheet 5.

The intermediate laminate 10 has substantially the same planar shape as the upper layer absorber 4A and the lower layer absorber 4B, and the intermediate laminate 10 is laminated between the upper layer absorber 4A and the lower layer absorber 4B. The peripheral edge of the intermediate laminated body 10 is arranged so as to substantially coincide with the peripheral edge of the upper layer absorber 4A and the lower layer absorber 4B. That is, the peripheral edge of the intermediate laminated body 10 is arranged between the peripheral edge of the upper layer absorber 4A and the peripheral edge of the lower layer absorber 4B, and the peripheral edge of the intermediate laminated body 10 is not covered by the upper layer absorber 4A or the lower layer absorber 4B. As a result, air can be discharged from the peripheral edge of the intermediate laminate 10 to the outside of the absorber 4.

Further, the laminated body in which the upper layer absorber 4A, the intermediate laminated body 10 and the lower layer absorber 4B are laminated in this order from the skin side is provided with a plurality of openings 11, 11 ... Through these in the thickness direction. The opening 11 is a portion that integrally penetrates the upper layer absorber 4A, the intermediate laminate 10, and the lower layer absorber 4B, and each member extends from the skin side surface of the upper layer absorber 4A to the non-skin side surface of the lower layer absorber 4B. Is a penetrating part that does not exist.

As described above, in the sanitary napkin 1, since the intermediate laminate 10 is interposed between the upper layer absorber 4A and the lower layer absorber 4B, as shown in FIG. 5, the intermediate laminate 10 Air flows between the fibers, and an air flow occurs in the plane direction between the upper layer absorber 4A and the lower layer absorber 4B. The air (moisture) that has flowed in the plane direction inside the intermediate laminate 10 is released from the peripheral edge of the intermediate laminate 10 to the outside of the absorber 4, and passes through the impermeable back sheet 2 to the outside of the napkin. It is discharged.

Further, since the sanitary napkin 1 is provided with a plurality of openings 11, 11 ... That penetrate the upper layer absorber 4A, the intermediate laminate 10 and the lower layer absorber 4B in the thickness direction, the thickness is increased through the openings 11. An air flow will occur in the direction. The air (humidity) flowing through the openings 11 in the thickness direction is discharged to the outside of the napkin through the impermeable back sheet 2. Further, since the opening 11 also communicates with the intermediate laminate 10, the air flowing through the opening 11 in the thickness direction flows into the intermediate laminate 10 and also flows in the plane direction, and the intermediate laminate 11 also flows. The air flowing through the 10 in the plane direction flows into the opening 11 and also flows in the thickness direction.

As described above, in the sanitary napkin 1, since the air flow can be generated in the plane direction and the thickness direction of the absorber 4, the moisture inside can be surely released to the outside, and the air permeability is high. It becomes hard to get stuffy.

A non-woven fabric is used as the intermediate laminate 10. Synthetic fibers are preferably used as the material constituting the non-woven fabric. As the synthetic fiber, a synthetic fiber mixed with the above-mentioned absorber 4 can be used, for example, a polyolefin-based material such as polyethylene or polypropylene, a polyester-based material such as polyethylene terephthalate or polybutylene terephthalate, a polyamide-based material such as nylon, and These copolymers and the like can be used, and these two types may be mixed. 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. In the case of hydrophobic fibers, it is desirable to use the synthetic fibers surface-treated with a hydrophilizing agent so as to have an affinity for body fluids. Further, by mixing the heat-sealing fiber, the strength at the time of wetting is improved, and the thermoplastic fiber having the heat crimpability imparts the strength at the time of wetting, and the non-woven fabric becomes bulky and has excellent air flowability. May be used.

The intermediate laminate 10 preferably has a lower density than the upper layer absorber 4A and the lower layer absorber 4B. Specifically, the density of the intermediate laminate 10, 1.5~20kg / ^{m 3,} preferably preferably set to 5~15kg / ^{m 3.} This density is a value obtained by dividing the weight by the volume calculated by multiplying the thickness at a pressure between pressure surfaces of 0.1 kPa measured using a KES-G5 handy compression tester by the plane dimension. By setting the density of the intermediate laminate 10 within this range, the air flowability inside the intermediate laminate 10 is improved, and it becomes easy for air to flow in the plane direction through the intermediate laminate 10.

By the way, in order to generate an air flow in the plane direction through the intermediate laminate 10, in addition to setting the installation position of the intermediate laminate 10 between the upper layer absorber 4A and the lower layer absorber 4B, the upper layer absorber 4A It is also conceivable to arrange it on the skin side of the body or on the non-skin side of the lower layer absorber 4B. However, when the intermediate laminate 10 is arranged on the skin side of the upper layer absorber 4A, the absorber 4 (upper layer absorber 4A and lower layer absorber 4B) is the easiest to secure the air flow in the plane direction. When the thickness of the absorber 4 is increased, moisture tends to be trapped in the absorber 4, and the air permeability to the outside of the absorber tends to decrease. Similarly, when the intermediate laminate 10 is arranged on the non-skin side of the lower layer absorber 4B, if the thickness of the absorber 4 is increased, moisture tends to be trapped in the absorber 4, and the absorber 4 is easily ventilated to the outside. There is a problem that it tends to decrease. Therefore, it is most desirable that the intermediate laminated body 10 is interposed between the upper layer absorber 4A and the lower layer absorber 4B like the sanitary napkin 1 from the viewpoint of improving air permeability and preventing stuffiness. Is.

The planar shape of the opening 11 can be polygonal or elliptical in addition to the circular shape shown in FIG. In the case of a polygon, if the number of corners is too large, the corners may collapse during use and the opening 11 may be crushed. Therefore, it is preferable to use a polygon of about a triangle to a hexagon. The size (diameter, length of one side or longitudinal dimension) of the opening 11 is preferably 1 mm to 10 mm, preferably 4 mm to 8 mm. If it is smaller than 1 mm, the effect of allowing air to flow is small, and the openings are crushed by external pressure, making it impossible for air to flow. On the other hand, if it is larger than 10 mm, the absorption performance is lowered and the absorber is likely to be twisted.

The total area obtained by summing the areas of the plurality of openings 11, 11 ... Is the area of the skin side surface of the laminate (the area of the laminate when the openings 11 and the emboss 12 described in detail later are not present). It is preferably formed at a ratio of 4% to 45%, preferably 8% to 20%. If the aperture ratio is smaller than 4%, sufficient air permeability in the thickness direction cannot be ensured. On the other hand, if the aperture ratio is larger than 45%, the absorption performance is lowered and the absorber is likely to be twisted.

The openings 11 are arranged in a predetermined pattern with respect to the plane of the laminated body of the upper layer absorber 4A, the intermediate laminated body 10 and the lower layer absorber 4B. In the example shown in FIG. 4, the sanitary napkins 1 are arranged in a grid pattern arranged in the longitudinal direction and the width direction, but may be arranged in a staggered pattern in which the sanitary napkins 1 are staggered every other row. The separation distance between the adjacent openings 11 and 11 is preferably approximately 5 mm to 60 mm, preferably 10 mm to 30 mm in order to secure a constant air flow rate and the strength of the laminated body. Further, as shown in the illustrated example, the opening ratio may be substantially uniform over the entire surface of the laminated body, or may be arranged in a predetermined area such as a region including the blood drainage port H, depending on the location. The aperture ratio may be different.

In order to provide the openings 11 in the laminated body of the upper layer absorber 4A, the intermediate laminate 10 and the lower layer absorber 4B, a convex roll provided with a convex portion corresponding to the opening 11 and a convex roll facing the opening are arranged. At the same time, the laminated body is passed between the concave roll provided with the concave portion corresponding to the convex portion of the convex roll, and the convex portion of the convex roll penetrates the laminated body and enters the concave portion of the concave roll. Therefore, the opening 11 that penetrates the laminated body can be formed. By heating the convex portion, the thermoplastic fiber contained in each member may be melted to facilitate the pore opening treatment.

By the way, in the state where the intermediate laminate 10 is arranged between the upper layer absorber 4A and the lower layer absorber 4B, the fiber density of each member has a dense-sparse-dense relationship from the skin side, so that the upper layer absorption is dense. There arises a problem that the body fluid does not easily permeate into the intermediate laminate 10 which is sparse from the body 4A, and the body fluid tends to accumulate in the upper absorber 4A. Therefore, at least in the region corresponding to the blood drainage port H, at a position not overlapping with the opening 11, a plurality of embosses 12 reaching the lower layer absorber 4B by pressing the upper layer absorber 4A from the skin surface side. It is desirable to give 12 ... As a result, as shown in FIG. 6, the body fluid is easily drawn into the pressed portion of the fiber densely formed by the embossing 12 by the capillary action, and the transfer of the body fluid from the upper layer absorber 4A to the lower layer absorber 4B is promoted. Will be done. Further, as shown in FIG. 6, some body fluids that travel on the surface of the upper layer absorber 4A enter the opening 11 and flow through the opening 11 in the thickness direction to be absorbed by the lower layer absorber 4B. ..

The planar shape of the embossed 12 is circular in the example shown in FIG. 4, but it can also be formed into a polygon, an ellipse, or the like. The plane shape of the emboss 12 is the plane shape of the bottom surface of the emboss. The size of the embossing 12 (diameter of the embossed bottom surface, length of one side or longitudinal dimension) is preferably 0.5 mm to 8 mm, preferably 1 mm to 5 mm.

The total area obtained by summing the areas of the plurality of embossed 12, 12 ... Is 1% with respect to the area of the skin side surface of the laminated body (the area of the laminated body when the openings 11 and the embossed 12 are not present). It is preferably formed at a ratio of ~ 30%, preferably 1.5% to 5%. If the embossing rate is higher than 30%, the flow of air flowing in the plane direction through the intermediate laminate 10 may be obstructed, which is not preferable.

The embossing 12 is provided at least in a region corresponding to the blood drainage port H at a position not overlapping with the opening 11. In the example shown in FIG. 4, the blood drainage port H and its surroundings are arranged in a grid pattern by being provided at intermediate positions of the openings 11, 11 ... Arranged in a grid pattern. The embossing 12 can be appropriately arranged according to the usage situation, such as being arranged at equal intervals or being unevenly distributed in a predetermined area.

In order to impart the embossing 12 to the laminated body of the upper layer absorber 4A, the intermediate laminated body 10 and the lower layer absorber 4B, an embossed roll provided with a convex portion corresponding to the embossed 12 and a flat surface arranged to face the embossed roll. It can be provided by passing the laminated body between the rolls.

The manufacturing procedure when the embossing 12 is provided will be described. After the embossing 12 is applied to the laminated body in which the intermediate laminated body 10 is interposed between the upper layer absorber 4A and the lower layer absorber 4B, the holes 11 are formed. It is preferable to apply the embossing 12 and the opening 11 at the same time. If the embossing 12 is applied after the opening 11 is provided, the opening 11 may be crushed due to the influence of pressing when the embossing 12 is applied, which is not preferable.

By the way, the central pressing groove 16, the front pressing groove 16a and the rear pressing groove 16b formed by pressing the liquid-permeable surface sheet from the skin surface side are the liquid-permeable surface sheet 3 as shown in FIG. It is preferable to squeeze from the skin surface side to the lower layer absorber 4B. As a result, the body fluid that has flowed into these squeezing grooves 16, 16a, 16b is easily absorbed by the lower layer absorber 4B, and the stuffiness inside the napkin can be suppressed.

Further, as shown in FIG. 1, the embossing 12 imparting region is preferably formed in the region of the central pressing groove 16. As a result, the body fluid in the central portion blocked by the central pressing groove 16 can be quickly diffused into the lower layer absorber 4B, the diffusivity of the body fluid is enhanced, and the stuffiness inside the napkin is more reliably performed. It will be possible to prevent it. Further, it is preferable that the embossing 12 is formed in the region surrounded by the front side pressing groove 16a and the region surrounded by the rear side pressing groove 16b, respectively. As a result, the body fluid that diffuses to the front side and the rear side from the central portion and is blocked by the front side pressing groove 16a and the rear side pressing groove 16b can be quickly diffused to the lower layer absorber 4B.

In order to verify the ventilation performance of the sanitary napkin 1, the normal absorber was subjected to only the embossing 12 ... (Comparative Example 1), and the normal absorber was subjected to the opening 11 ... And the embossing 12 ... (Comparative Example 2), an intermediate laminate 10 was interposed between the upper layer absorber 4A and the lower layer absorber 4B, and the holes 11 ... And the embossing 12 ... Are provided (Example). , Air permeability test was performed.

The air permeability test was performed by the Garley testing machine method conforming to JIS P 8117 (2009). In this Garley testing machine method, when the inner cylinder is inserted into an outer cylinder filled with oil, the air inside the inner cylinder is compressed by the gravity of the inner cylinder and passes through the test piece, and the inner cylinder gradually descends. The time (t seconds) at which a constant volume (100 ml) of air has passed through the test piece is measured, and the ISO air permeability is obtained from the value by the following equation (1).
ISO air permeability = 135.3 / t …… (1)
In the above test, the ISO air permeability in the thickness direction through which air passes from one side surface of the test piece to the other side surface is measured as the ventilation performance in the thickness direction, and one of the test pieces is measured as the ventilation performance in the plane direction. A plastic plate having an opening with a diameter of 30 mm is arranged on the side surface (air inflow side surface), and a plastic plate having no opening is arranged on the other side surface of the test piece, and the plastic plate having no opening is arranged through the opening toward the peripheral edge of the test piece. The ISO air permeability in the plane passing through was measured. The diameter of the air passage portion of the Garley testing machine is 30 mm. The measurement was performed three times each and evaluated based on the average value.

The specifications of the test piece are as follows. The plane size is 210 × 90 mm, the pulp weight is 265 g / m ² , and the polymer weight is 8.5 g / m ² . In the examples, the thickness of the upper layer absorber 4A is 5.5 mm, the thickness of the lower layer absorber 4B is 5.5 mm, and the intermediate laminate 10 is a mixture of polyethylene terephthalate (PET) and polypropylene (PP) with a diameter of 40 g / m ^2. The thickness is 3.6 mm, the density is 11 kg / m ³ , the diameter of the hole 11 is 6.0 mm, the aperture ratio is 8%, the diameter of the emboss 12 is 2.0 mm, and the embossing rate is 3. It is 0.6%. In Comparative Example 1, the thickness of the absorber was 8.1 mm, the diameter of the embossing was 2.0 mm, and the embossing rate was 3.6%. In Comparative Example 2, the thickness of the absorber was 7.6 mm, the diameter of the pores was 6.0 mm, the aperture ratio was 8%, the diameter of the embossing was 2.0 mm, and the embossing ratio was 3.6%. The thickness is a value when the pressure between the pressurized surfaces is 0.1 kPa measured using a KES-G5 handy compression tester.

As a result, as shown in Tables 1 and 2, when the Example and Comparative Example 1 (embossing only) are compared, the Example has better air permeability in each of the thickness direction and the plane direction (ISO transparency). The result was obtained.

Further, when comparing Example and Comparative Example 2 (opening + embossing), in the thickness direction, the air permeability is about the same as that of Comparative Example 2 in which the holes are provided, but in the plane direction. As a result, the results of the examples were better in breathability.

As a result, it was confirmed that the air permeability in the thickness direction was improved by providing the opening 11, and the air permeability in the plane direction was improved by arranging the intermediate laminate 10.

[Examples of other forms]
(1) In the above embodiment, the absorber 4 has a two-layer structure including an upper layer absorber 4A and a lower layer absorber 4B, but the absorber may have a multi-layer structure of three or more layers. In this case, the intermediate laminate 10 may be arranged between each layer of the absorber, or only one layer may be arranged between arbitrary layers.
(2) The opening 11 is shown so as to penetrate the upper layer absorber 4A, the intermediate laminate 10 and the lower layer absorber 4B in parallel with the thickness direction, but is inclined with respect to the thickness direction. It may be provided so as to penetrate. Specifically, the angle formed by the central axis of the opening 11 and the virtual line parallel to the thickness direction is preferably 0 ° to 60 °, particularly preferably 0 ° to 30 °.
(3) The size of the opening 11 may not be the same in all of the upper layer absorber 4A, the intermediate laminate 10 and the lower layer absorber 4B, but may be formed in different sizes in each member. Good. For example, the member on the skin side (upper layer absorber 4A side) may be larger, or the member on the non-skin side (lower layer absorber 4B side) may be larger. As a result, the opening 11 can be reliably held even when the leg pressure acts from both sides in the width direction of the napkin during mounting and the central portion in the width direction of the napkin bends so as to bulge toward the non-skin side or the skin side. Will be.

1 ... Sanitary napkin, 2 ... Impermeable back sheet, 3 ... Liquid permeable front sheet, 4 ... Absorber, 4A ... Upper layer absorber, 4B ... Lower layer absorber, 5 ... Encapsulated sheet, 6 ... Three-dimensional gather Non-woven fabric for forming, 7 ... Side non-woven fabric, 10 ... Intermediate laminate, 11 ... Opening, 12 ... Embossing

Claims (5)

In an absorbent article in which an absorber is interposed between the liquid-permeable front sheet and the back sheet,
The absorbent body includes a top layer absorbent body arranged on the skin side is composed of a cotton-like pulp and water-absorbing polymer, and a lower absorbent body arranged configured non-skin side by a cotton-like pulp and water absorptive polymer Have and
An intermediate laminate made of a non-woven fabric of thermoplastic fibers which is a synthetic fiber material and has thermal crimpability is interposed between the upper layer absorber and the lower layer absorber, and the intermediate laminate is the upper layer absorber. And has the same planar shape as the lower layer absorber, the peripheral edge of the intermediate layered body is not covered by the upper layer absorber and the lower layer absorber, and the upper layer absorber, the intermediate layered body and the lower layer absorber are formed in the thickness direction. An absorbent article characterized in that it is provided with a plurality of openings penetrating the. The absorbent article according to claim 1, wherein the intermediate laminate has a lower density than the upper layer absorber and the lower layer absorber. The absorbent article according to any one of claims 1 and 2 , wherein the area of the opening is formed at a ratio of 4% to 45% with respect to the area of the absorber. Claims 1 to 3 in which at least a region corresponding to a body fluid discharge site and a position not overlapping with the opening is embossed to reach the lower layer absorber by squeezing the upper layer absorber from the skin surface side. Absorbent article according to any. The absorbent article according to claim 4 , wherein the embossed area is formed at a ratio of 1% to 30% with respect to the absorber area.

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