JP2003275239A - Absorptive article - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an absorptive article in which the performance of a surface sheet having excellent absorptive properties and feeling can be effectively manifested and an efficient and economical manufacturing method thereof. <P>SOLUTION: In the absorptive article provided with the liquid-permeable surface sheet 10, a liquid-impermeable back sheet 30, and a liquid holding absorbent 40 laid between these both sheets and having, in a skin contacting face, an uneven region 11, in which many convex portions are regularly formed, and a non-uneven region 12 in which convex portion (not illustrated), whose height is lower than the convex portion 4 in the uneven region 11, are formed or the convex portions are not formed, the uneven region 11 is formed of a laminated sheet 10 in which a first layer arranged on the skin side and a second layer arranged on the absorbent side are laminated and are partly connected in a connecting portion of a predetermined pattern, and a number of the convex portions 4 in the uneven region 11 are formed by deforming parts other than the connecting portion 3 of the first layer into a convex form by contraction of the second layer. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an absorbent article having a concavo-convex region on a part of its skin-contacting surface and a method for manufacturing the same.

[0002]

2. Description of the Related Art The problem of developing absorbent articles such as sanitary napkins and disposable diapers is to absorb and retain discharges from the human body such as menstrual blood and urine so that they do not leak. In addition, since it is used in close contact with the wearer's skin, the wearer's skin is prevented from becoming uncomfortable due to stuffiness and the like.

In order to solve the above-mentioned problems, one of the two fiber layers integrated by partial joining is contracted, and the other fiber layer is deformed to form a non-woven fabric, which is made of an absorbent material. It has been proposed for use as a topsheet for articles. For example, in Japanese Patent No. 3131557,
As a non-woven fabric suitable for disposable diapers and sanitary napkins, etc., a layer containing heat-shrinkable fibers and heat-sealing fibers and a layer containing non-heat-shrinkable fibers are laminated, and both layers are partially joined and integrated. After that, a wrinkled nonwoven fabric produced by heat-shrinking a layer containing heat-shrinkable fibers is described. However, the multi-wrinkled non-woven fabric described in the publication has the same shape on the entire surface sheet, so that it follows the movement of the body when considering the shape stability of the part where the effect of the shape is most desired. When the surface sheet is deformed as described above, the effective surface shape may not be maintained. In addition, the conventionally proposed absorbent articles have not always been capable of effectively exhibiting the performance of such a nonwoven fabric.

Therefore, an object of the present invention is to provide an absorbent article capable of effectively exhibiting the performance of a surface sheet having excellent absorbency, texture, and shape stability of surface irregularities during use, and its efficiency. And to provide an economical manufacturing method.

[0005]

SUMMARY OF THE INVENTION The present invention comprises a liquid-permeable top sheet, a liquid-impermeable back sheet, and a liquid-retaining absorber interposed between these two sheets. In addition, an absorption having an uneven region in which a large number of convex parts are regularly formed, and a non-concave region in which convex parts having a height lower than that of the convex parts in the uneven region are formed or in which no convex part is formed In the elastic article, the skin contacting surface of the uneven region is formed by laminating a first layer arranged on the skin side and a second layer arranged on the absorber side and partially bonding at a bonding portion having a predetermined pattern. The plurality of convex portions in the concave-convex region are formed of a laminated sheet, and a portion other than the joint portion of the first layer is formed into a second portion.
The object described above is achieved by providing an absorbent article that is formed by being deformed into a convex shape by contraction of a layer. Furthermore, according to the present invention, the laminated sheet is arranged only in the concavo-convex region, the second layer in the concavo-convex region is thermally shrunk, and the second layer does not exist in the non-concave region. The above object is achieved by providing a sex article.

Further, the present invention is a method for manufacturing the above-mentioned absorbent article, wherein a first layer arranged on the skin side and a second layer arranged on the absorber side are partially joined to form a laminated sheet. The process of obtaining,
A step of fixing the laminated sheet to the other member of the absorbent article as the surface sheet, and a heat treatment to the laminated sheet before or after fixing it to the other member to heat-shrink the second layer and The method further comprises the step of deforming a portion of the first layer other than the joint portion into a convex shape, the first layer and the second layer
A low bonding region having a low area ratio of the bonding portions of the first layer and the second layer, and a high bonding region having a high area ratio of the bonding portions of the first layer and the second layer when bonding the layers Is provided, and the uneven region is formed by the low bonding region, and the non-uneven region is formed by the high bonding region.

Further, the present invention is the method for manufacturing an absorbent article according to claim 1, wherein the first layer arranged on the skin side and the second layer arranged on the absorber side are partially joined. To obtain a laminated sheet, fixing the laminated sheet to another member of the absorbent article as the surface sheet, and partially heat treating the laminated sheet before or after fixing it to the other member. And heat-shrinking the second layer and deforming the portion of the first layer other than the joint portion into a convex shape, and forming the concavo-convex region by the heat-treated portion of the laminated sheet. At the same time, the present invention provides a method for manufacturing an absorbent article, in which the non-concave / convex region is formed by a portion of the laminated sheet which has not been subjected to the heat treatment.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will now be described based on its preferred embodiments with reference to the drawings. As shown in FIGS. 1 and 2, the sanitary napkin 20 of the first embodiment has a liquid-permeable top sheet 10, a liquid-impermeable back sheet 30, and a liquid-retaining material interposed between these sheets. The absorbent body 40 is provided, and the uneven surface region 11 in which a large number of convex parts 4 are regularly formed on the skin contact surface, and the convex part having a height lower than the convex part 4 in the uneven surface region 11 are formed. It has a non-concavo-convex region 12. The height of the convex portion in the non-concavo-convex region 12 is significantly lower than that of the convex portion 4 in the concave-convex region 11, and therefore the illustration thereof is omitted. The sanitary napkin 20 is formed substantially vertically long, and the concavo-convex region 11 in the present embodiment is arranged such that the napkin is longitudinally arranged in the front part A and the excretion part opposing part (opposed to the liquid excretion part of the wearer). The excretion point portion is formed in the excretion portion facing portion B when the excretion point portion is divided into a widthwise center portion B and the rear portion C, and more specifically, the excretion portion opposing portion in the width direction central portion (the excretion point portion). ) Is formed. On the other hand, the non-concavo-convex region 12 is the concavo-convex region 11
Is formed around the concavo-convex region 11 so as to surround the.
In the present embodiment, the concavo-convex area 11 and the peripheral edge seal portion 1 are used.
The entire area sandwiched between the areas 3 and 3 is the non-relief area 12.

Top sheet 1 of sanitary napkin 20
0 is the first placed on the skin side, as shown in FIGS. 3 and 4.
Laminated sheet 1 in which a layer 1 and a second layer 2 disposed on the absorber side are laminated and partially joined at a joint portion 3 having a predetermined pattern
It consists of zero. 3 and 4 are diagrams showing the laminated sheet 10 in the uneven region 11. Since the topsheet 10 in this embodiment is composed of such a laminated sheet itself, the same reference numeral (1) as the topsheet is applied to the laminated sheet.
0) is attached.

The joint portions 3 of the first layer 1 and the second layer of the laminated sheet 10 in the concavo-convex region 11 are arranged in a so-called staggered pattern (see FIG. 5), and each joint portion 3 is a plane surface. It is circular and formed discontinuously. Junction 3
Is compacted, and has a smaller thickness and a larger density than other parts of the laminated sheet 10.
The joints of the first layer 1 and the second layer 2 of the laminated sheet 10 in the non-concave region 12 are arranged in the same pattern as in the concavo-convex region 11, and the individual joints are similarly consolidated. . However, the diameters (areas) of the individual joints and / or the pitches between the joints are different, so that the area ratio R1 of the joints in the concavo-convex region 11 is larger than the area ratio R2 of the joints in the non-concave region 12. It's getting low.

The area ratio of the joint portion of the first layer 1 and the second layer 2 is the ratio of the total area of the joint portion 3 contained in the unit area (100 cm ² ) of the laminated sheet 10 to the unit area (100 cm ² ). It is represented and is measured in the laminated sheet before shrinkage.

Area ratio R1 of the joint portion in the uneven region 11
Is smaller than the area ratio R2 of the joint portion in the non-concave / convex region 12, the height of the convex part generated in the concavo-convex region 11 can be made higher than the height of the convex part generated in the non-concave region 12.

Area ratio R1 of the joint portion in the uneven region 11
Is preferably 2 to 20%, particularly 2 to 15%, and especially 3 to 10%. If the area ratio R1 is more than 20%,
Since a space for producing a sufficient height by the swelling (convex portion) of the first layer formed by the contraction cannot be made, as a result, a convex portion having a sufficient height may not be obtained. On the other hand, if the area ratio R1 is less than 2%, the fiber deformation for forming the swelling (convex portion) of the first layer needs to be performed in a larger space. It may not be possible to obtain a convex portion.

On the other hand, the area ratio R2 of the joint portion in the non-concavo-convex region 12 is preferably 15 to 50%, particularly preferably 15 to 35%. When the area ratio R2 exceeds 50%, the embossed portion is basically a region where it is difficult to absorb the liquid, which may cause absorption inhibition. Area ratio R2 is 15%
If it does not satisfy the above condition, the concavo-convex shape of the surface sheet and the stretchable physical properties tend to be uniform, so it is not preferable from the viewpoint of providing the surface concavities and convexities at appropriate sites and further stabilizing the shape.

The ratio (R2 / R1) of the area ratio R1 of the concavo-convex area 11 to the area ratio R2 of the non-concave area 12.
Is at the same time (heat treatment temperature, heat treatment time, etc.) from the point of partially designing the uneven region, 1.5 to 8, especially 2 to
It is preferably 5.

The joint portion 3 in both the regions 11 and 12 is formed by various joining means such as heat embossing, ultrasonic embossing, and bonding with an adhesive. The joint portion 3 in the present embodiment is circular in both regions 11 and 12, but the joint portion 3 may be circular, oval, triangular, rectangular, or a combination thereof. In addition, the joint portion 3 has a continuous shape, for example, a linear shape such as a straight line or a curved line,
It may be formed in a lattice shape or the like. 6A and 6B show another example of the formation pattern of the joint portion formed in the uneven area 11 and the non-uneven area 12.
It was shown to. As long as the area ratio of the joints can be made different, the shape of the individual joints in both regions 11 and 12 and the pattern forming the plurality of joints may be the same or different in both regions 11 and 12.

The first layer 1 is composed of a fiber aggregate, and as shown in FIG. 3, the first layer 1 in the concavo-convex area 11 is formed.
Has a convex portion on the skin side other than the joint portion 3 with the second layer 2. That is, when the laminated sheet 10 is viewed in a plan view, the portions located between the joint portions 3 of the first layer 1 (specifically, the rectangular portions having the joint portions 3 at the four corners) are convex (dome-shaped). And thus the number of protrusions 4
Are formed on the skin side surface of the topsheet 10. Each convex portion 4
The inside of the is filled with the fibers forming the first layer 1,
The interface between the first layer 1 and the second layer 2 between the joints is not joined but is in close contact with the entire region. The shape of the convex portion 4 is mainly determined by the form of the fiber assembly forming the first layer 1 and the pattern of the joint portion 3. The first layer 1 in the non-concavo-convex region 12 has a convex portion on the skin side other than the joint portion 3 with the second layer 2 as in the concavo-convex region 11, but the degree thereof is extremely small. The height of the convex portion formed by is extremely smaller than the height of the convex portion in the concavo-convex region 11. The first layer 1 is composed of an aggregate of fibers having a different type and / or composition from the fibers forming the second layer 2.

The second layer 2 of the laminated sheet 10 maintains a substantially flat surface between the joint portions 3 (see FIG. 4). When the laminated sheet 10 in the uneven area 11 is viewed as a whole, the second layer 2 The structure is flat on the side and has a large number of protrusions on the first layer 1 side. The convex portion 4 formed by the first layer 1 may have a hollow (hollow) inside instead of being filled with fibers. In this case, the fiber assembly forming the first layer 1 is made of non-woven fabric or knitted fabric.

Further, as another embodiment for designing the concavo-convex region in a desired portion, a laminated sheet having a second layer mainly composed of fibers capable of contracting only the concavo-convex region may be formed. In this form, the part (emboss or hot melt) that partially joins the first layer and the second layer exists only in the uneven region, and the above comparison of the embossed area ratios is not necessary. However, it is effective because there is a cost merit by reducing (appropriate place) the multi-layer region. As a problem of the above-described embodiment, there is a phenomenon in which a difference in material deformation due to the presence or absence of shrinkage easily occurs in a boundary region between a laminated portion having a shrinkable layer and a single layer portion having no shrinkable layer,
It can be said that this is one of the useful means for stabilizing the surface shape by partially arranging the concavo-convex region, which is the object of the present invention.

The height T (see FIG. 4) of the convex portion 4 in the concave-convex area 11 is 0.5 to 5 mm, particularly 1 to 3 mm from the viewpoint of providing the concave-convex area 11 with sufficient compressive deformability and bulkiness.
Is preferred. By setting the height T of the convex portion to 0.5 mm or more, the contact area with the skin can be reduced, and the occurrence of stuffiness or rash due to the skin being used being blocked can be prevented. In addition, the height T of the convex portion is 5
By setting it to be equal to or less than mm, the distance until the absorbed liquid reaches the second layer 2 becomes small, and the liquid can be absorbed smoothly even under a low load. On the other hand, the convex portion (not shown) in the non-concavo-convex region 12 further enhances the fit / concentrated absorbability (does not spread) of the excretion region (central portion) to be the concavo-convex region, and the convex portion shape of the central region. Is preferably 0 to 0.5 mm, particularly preferably 0 to 0.3 mm from the viewpoint of stabilizing Furthermore, the ratio of the height T1 of the convex portion of the non-concave area 12 to the height T of the convex portion 4 of the concave and convex area 11 (T / T1)
Is 1.5 from the viewpoint of fitness / concentration absorbability (does not spread) of the excretion region (central part) and stabilization of the convex shape.
It is preferable that it is -5, especially 1.5-3.

Here, the height of the convex portion 4 is measured as follows. First, the uneven area 11 and the non-uneven area 12
From each, cut out a test piece with a length and width of mm x mm. Then, each of the cut surfaces is formed by a line which is substantially parallel to the longitudinal direction [the fiber orientation direction of the fiber assembly constituting the first layer (the flow direction at the time of manufacturing the fiber assembly)] and which passes through each joint. High scope (Olympus, SZH
In 10), an enlarged photograph of this section is obtained. The heights from the top of the protrusion 4 to the bottom (the upper surface of the adjacent joint 3) are measured by matching the scales of the enlarged photographs (see 4).

The laminated sheet 10 is fluffy soft and from the viewpoint of follow supple relative movement of the body, a basis weight of 20 to 150 g / m ^2, especially 20 to 80 g / m ²
Is preferred. The basis weight is 50 for the laminated sheet 10.
The measurement piece is cut into a size of mm × 50 mm or more, the weight of the measurement piece is measured using an electronic balance with a minimum display of 1 mg, and converted into a basis weight.

In designing a surface sheet that is soft and fluffy and supple with movement of the body,
The first layer 1 of the laminated sheet 10 has a basis weight of 5 to 35 g /
m ² , particularly preferably 5 to 25 g / m ² , and the second
Layer 2 has a basis weight of 10 to 50 g / m ² , especially 10 to 4
It is preferably 0 g / m ² . The basis weights of the first and second layers are the respective basis weights before joining both layers.

In the laminated sheet 10 according to this embodiment, the heat shrinkable region 2 of the second layer is made of a material exhibiting an elastomeric behavior, and has a predetermined size when the second layer 2 is stretched in its plane direction. Express contraction stress. Therefore, the (heat shrinkage) region of the laminated sheet 10 exhibits elastic behavior as a whole and has elasticity. by this,
Since the surface irregularity area has elasticity, the followability to the wearer's movement of the part where the effect of the surface irregularity is desired is further improved, the fit of the absorbent article is improved, and liquid leakage is effective. To be prevented. The first layer 1 need only be stretchable, and it does not matter whether or not it behaves like an elastomer.

From the viewpoint of exhibiting a sufficiently high elastomeric behavior, the laminated sheet 10 has an elongation recovery rate at 50% elongation of 50% or more, particularly 60% or more, and particularly 60%.
It is preferably ˜90%. The stretch recovery rate may have different values in the flow direction and the width direction of the laminated sheet 10, but if the value of the stretch recovery rate measured in at least one of the directions is within the above range, sufficient elastomeric behavior is obtained. Is expressed.

The elongation recovery rate is measured by the following method.
Toyo Baldwin Co., Ltd. tensile / compression tester RTM
It is measured in tension mode using -100 (trade name). First, the laminated sheet 10 is cut into a size of 50 mm × 50 mm and a measurement piece is sampled. The test piece was set with an initial sample length (distance between chucks) of 30 mm between air chucks mounted on the tensile / compression tester, and the chuck attached to the load cell (rated output 5 kg) of the tensile / compression tester was set to 100 mm.
The test piece is stretched by raising it at a speed of mm / min. When the measurement piece extends 50% of the initial sample length, that is, when it extends 15 mm, the moving direction of the chuck is reversed and the chuck is moved to 100%.
It is lowered at a speed of mm / min and returned to the position of the initial sample length. The relationship between the load detected by the load cell and the elongation of the measurement piece during the operation during this period is recorded on a chart, and the elongation recovery rate is calculated from the following formula (1) based on this chart. Elongation recovery rate = recovery elongation / maximum elongation length (= 15 mm) (1) Here, the recovery elongation is the maximum when the chuck is lowered from the maximum elongation length (= 15 mm) and zero load is recorded for the first time. It is defined as the chuck movement distance from the extension length.

The fibers constituting the first layer 1 and the second layer 2 will be described. As the fibers constituting the first layer 1, heat-fusible fibers, particularly fibers made of a thermoplastic polymer material are preferably used. . Examples of the thermoplastic polymer material include polyolefin such as polyethylene and polypropylene, polyester such as polyethylene terephthalate, and polyamide. In addition, core-sheath type composite fibers and side-by-side composite fibers composed of these thermoplastic polymer materials are combined.
Side-type composite fibers can also be used. Also the first layer 1
As the fibers constituting the above, those which do not substantially have heat shrinkability or which do not heat shrink below the heat shrink temperature of the fibers constituting the second layer 2 described later are used. The fineness of the fiber is
It is preferably from 0.5 to 20 dtex, and particularly from 1.0 to 10 dtex, from the viewpoint of easy production of the fiber and exhibiting a good feel.

As the fiber forming the second layer, a fiber made of a thermoplastic polymer material and having heat shrinkability is used. Further, as the fiber, one having an elastomeric behavior is used. Examples of such fibers include latently crimpable fibers. The latently crimpable fiber is a fiber which can be handled in the same manner as a conventional nonwoven fabric fiber before being heated, and has a property that a helical crimp is developed and contracted by heating at a predetermined temperature. is there. By using the latently crimpable fiber, both heat shrinkability and elastomeric behavior can be exhibited simultaneously.

The latently crimpable fiber comprises, for example, an eccentric core-sheath type composite fiber or a side-by-side type composite fiber containing two types of thermoplastic polymer materials having different shrinkage rates as components. Examples thereof include those described in Japanese Patent Application Laid-Open No. 9-296325 and Japanese Patent No. 2759331. The first layer 1 and the second layer 2 may be mixed with fibers other than the above, for example, water-absorbent fibers such as rayon, cotton, and hydrophilic acrylic fibers.

The form of the aggregate of fibers constituting the first layer is, for example, a web formed by a card method, a nonwoven fabric formed by a heat fusion method, a nonwoven fabric formed by a hydroentanglement method, or a needle punch method. The formed non-woven fabric, the non-woven fabric formed by the solvent bonding method, the non-woven fabric formed by the spun bond method, the non-woven fabric formed by the melt blown method, or the knitted fabric is exemplified. When the first layer 1 is in the form of a web formed by the card method, a convex portion which is bulky and is filled with fibers constituting the web is formed on the laminated sheet 10, and the fibers are convex. Orient along the part. On the other hand, the first layer 1
Is in the form of a non-woven fabric or knitted fabric, hollow convex portions are formed. In particular, when the first layer 1 is configured by using a web formed by the card method, the first layer 1 has an extremely sparse structure, and the laminated sheet 10 of the present invention has a high viscosity and a high permeability. It becomes possible to hold. Also laminated sheet 1
The compressive deformability when 0 is compressed in the thickness direction also increases. Examples of the highly viscous liquid include loose stools or menstrual blood, detergents or moisturizers for humans, or detergents for objectives.

The web formed by the card method is
It is a fiber assembly before being made into a non-woven fabric. That is, a post-treatment applied to a card web used for producing a nonwoven fabric, for example, a fiber aggregate in a state in which fibers are extremely loosely entangled with each other in a state where heat fusion treatment by an air-through method or a calendar method has not been performed. It is the body. When the web formed by the card method is used for the first layer, the first layer 1 and the second layer 2 are bonded at the same time, or after the bonding, the fibers in the first layer 1 are heat-sealed. Alternatively, use solvent adhesion or mechanical entanglement.

On the other hand, the form of the aggregate of fibers constituting the second layer is (1) a web containing latently crimpable fibers and formed by the card method, or (2) a non-woven fabric having heat shrinkability. , Non-woven fabric formed by heat fusion method, non-woven fabric formed by hydroentanglement method, non-woven fabric formed by needle punch method, non-woven fabric formed by solvent bonding method, non-woven fabric formed by spunbond method, Meldblown method The non-woven fabric formed by. Here, the non-woven fabric having heat shrinkability is a non-woven fabric having a property of shrinking by heating at a predetermined temperature. Furthermore, (3) a net having a heat shrinkability can be mentioned.

As the material for forming the absorbent body and the back sheet in the sanitary napkin (absorbent article), those conventionally used for sanitary napkins, disposable diapers and the like can be used without particular limitation. For example, the absorbent body may be a fiber assembly or a fiber assembly and a superabsorbent polymer covered with a coating sheet made of water-permeable paper or nonwoven fabric. Examples of the form of the fiber assembly constituting the absorber include a nonwoven fabric or a fiber web, and the existence form of the superabsorbent polymer is maintained between the interfiber spaces of the fiber assembly or between the layers of the fiber assembly having a multilayer structure. The form which is carried out is mentioned. Moreover, you may interpose a diffusion paper etc. between a surface sheet and an absorber.

According to the sanitary napkin of the first embodiment,
The excretion part facing part of the sanitary napkin (the central part in the longitudinal direction) B
In addition, since the concavo-convex region 11 having the above-described configuration is formed, not only the concavo-convex region B having elasticity with respect to the excretion part fits well, but also the first layer rises by utilizing the contraction of the second layer. Since the second layer forms a space with a relatively large fiber space and a small fiber density (sparse) and the second layer has a relatively large fiber density (dense), a good density gradient is designed, so that the liquid drawing force is increased. It is larger than the surrounding area, which allows it to develop a performance that prevents the liquid from spreading in the center. In addition, since the area is more elastic than the surrounding area, deformation (screws and wrinkles) around the area is less likely to be transmitted, and it is easy to maintain the uneven shape.

In the present invention, the concavo-convex region 11 having the same structure as described above can be formed in another portion of the sanitary napkin. The sanitary napkin shown in FIG. 7 (a) has uneven areas 11 on both sides in the longitudinal direction (both sides of the excretion point portion), and the uneven areas 11 are non-uneven areas 12.
Has become. According to the sanitary napkin having such a configuration,
By arranging stretchable areas on both sides in the longitudinal direction where the deformation load of the napkin is applied most during use, the stress applied to the napkin can be relieved and the ideal mounting shape that is resistant to twisting can be maintained. Further, it is preferable that the uneven region is water-repellent, and in this case, it is effective to prevent leakage due to liquid bleeding from the center. Further, since it has an uneven shape, it can not only reduce the contact area with the skin and provide a non-greasy and soft wearing feeling, but also can dampen and absorb the spilled liquid flowing through the surface.

The sanitary napkin shown in FIG. 7 (b) has a concavo-convex region 11 at the rear portion in the longitudinal direction, and the other region is a non-concavo-convex region 12. According to the sanitary napkin having such a configuration, since it has elasticity, it can fit tightly in the gap (groove) of the hips, and the uneven portion damps the liquid that flows and leaks along the groove of the hips. Can be absorbed,
It is effective in preventing back leakage.

The sanitary napkin of the first embodiment can be manufactured efficiently and economically by the following method, for example. That is, a second layer composed of a thermoplastic polymer material, having heat shrinkability, and further comprising an aggregate of fibers including fibers exhibiting elastomeric behavior, and a second layer composed of the thermoplastic polymer material and not substantially heat shrinkable. Alternatively, the first layer, which is an aggregate of fibers that do not heat shrink below the heat shrinkage temperature of the fibers that form the second layer, is superposed, and both are partially bonded at the bonding portion of a predetermined pattern. At the time of joining the first layer and the second layer, a low joining region having a low area ratio of the joining portion of the first layer and the second layer is formed at a site corresponding to the uneven region of the sanitary napkin in the laminated sheet, A high bonding region in which the area ratio of the bonding portion of the first layer and the second layer is higher than that of the low bonding region is formed in a portion other than the portion corresponding to the concavo-convex region of the sanitary napkin in the laminated sheet. For joining the two layers, a hot embossing roll device or the like including a combination of a concavo-convex roll having a plurality of regions having different concavo-convex patterns on its peripheral surface and a smooth roll can be used.

Then, on the laminated sheet having the joint portion formed thereon,
By subjecting the fibers constituting the second layer to a heat treatment at a temperature not lower than the temperature at which thermal contraction starts, the portions other than the joint portion of the first layer in the low joint region are deformed into a convex shape to form a large number of convex portions. At the same time, the portion of the high bonding region other than the bonding portion of the first layer is deformed into a convex shape to form a convex portion lower than that of the low bonding region. The low-bonding region where a large number of convex portions are formed becomes the concavo-convex region 11, and the high-bonding region where a large number of convex portions is formed becomes the non-concave region 12. It is also possible to increase the area ratio of the joint portion in the high joint region to form the non-relief region 12 in which the convex portion is not substantially formed. Further, as another embodiment, only for a desired uneven region placement portion,
By partially joining and integrating the second layer and performing heat treatment, only the region in which the second layer is laminated contracts, and the concavo-convex design can be made at a desired site. In order to shrink the second layer, for example, a tabletop constant temperature dryer or an air-through heat treatment machine used when manufacturing a heat-bonded nonwoven fabric is used. And the sanitary napkin is fixed to the other member (absorbent body, back sheet, etc.) of the sanitary napkin according to a conventional method by using the laminated sheet having the concavo-convex region 11 and the non-concavo-convex region 12 as a surface sheet. Is obtained.

In the above-mentioned method, the laminated sheet after heat treatment to form the convex portions was fixed to another member of the sanitary napkin (absorber, back sheet, etc.). The convex portion can be formed by heat-treating the laminated sheet after fixing it to another member.

The sanitary napkin of the third embodiment is different from the sanitary napkin except that the method of forming the concavo-convex area 11 and the non-concave area 12 is different.
It has the same configuration as that of the first embodiment. In the following, differences from the first embodiment will be mainly described,
Description of similar configurations will be omitted. The description of the first embodiment is applied to points that are not particularly described. The surface sheet in the sanitary napkin of the third embodiment is similar to the first embodiment, in which a first layer arranged on the skin side and a second layer arranged on the absorber side are laminated to form a joint portion having a predetermined pattern. It is composed of a laminated sheet partially joined with.
In the laminated sheet used in the second embodiment, the area ratio of the joint portion of the first layer 1 and the second layer 2 is constant over the entire area. The laminated sheet according to the third embodiment is heat-treated only partially in the manufacturing process of the sanitary napkin, and in the heat-treated portion, the portion other than the joint portion of the first layer is the second layer. The first layer, which has been deformed to be convex due to the contraction and has not been subjected to the heat treatment, is not deformed to be convex due to the contraction of the second layer. Then, a portion where a large number of convex portions are formed by heat treatment is a concavo-convex area, and a portion where heat treatment is not performed and a convex portion is not substantially formed is a non-concavo-convex area. The heat treatment for the laminated sheet may be performed either before or after being fixed to another member of the sanitary napkin (such as the absorber or the back sheet).

According to the sanitary napkin of the third embodiment,
The same operational effects as the sanitary napkin of the second embodiment are exhibited. In addition, according to the napkin in which the concavo-convex region forming portion in the napkin of the second embodiment is replaced with FIGS. 7A and 7B, the concavo-convex region forming portion in the napkin of the first embodiment is formed respectively. The same operational effect as the napkin in which the same position is replaced is obtained.

The present invention is not limited to the above embodiment. For example, the first layer arranged on the skin side and the second layer arranged on the absorber side.
The entire surface of the laminated sheet (for example, the laminated sheet before the heat treatment used in the second embodiment) in which the layers are laminated and partially joined at the joining portion having a predetermined pattern is subjected to heat treatment, and a large number of convex portions are formed on the entire surface. It is also possible to obtain the absorbent article of the present invention by sticking the uneven sheet formed uniformly on only a part of the skin contact surface (center portion, both side portions, rear portion, etc.) (third embodiment). Form). In this case, the portion to which the uneven sheet is not attached becomes the non-uneven area in which the convex portion is not formed. As the sheet material to which the concavo-convex sheet is attached, a breathable material conventionally used as a material for forming a surface sheet, for example, a known nonwoven fabric can be used without particular limitation. Examples of the method for attaching the uneven sheet include a fixing method using hot melt, a fixing method using heat sealing and ultrasonic waves, and the like.

The first layer 1 constituting the laminated sheet 10
As the second layer 2, other than the above-mentioned fiber aggregate,
Materials that are substantially air permeable may also be used. Such materials include breathable films, apertured films, nets, or composites thereof, or composites of these with aggregates of fibers.

Further, as the second layer 2, an aggregate of fibers including elastomer fibers, an elastomer film, and an elastomer net can be used. Materials usable as the elastomer include natural rubber, isoprene rubber, butadiene rubber, 1,2-polybutadiene, styrene-butadiene rubber, chloroprene rubber, nitrile rubber, butyl rubber, ethylene-propylene rubber, urethane rubber, and thermoplastic elastomer. Various rubbers known as, for example, urethane-based, styrene-based, ester-based, olefin-based, amide-based rubber having a hard segment, ethylene-α-olefin copolymers polymerized using metallocene as a catalyst, and the like. .

The absorbent article according to the present invention includes:
Examples include sanitary napkins, disposable diapers, incontinence pads, panty liners, and the like. The description omitted part in one embodiment and the requirement that only one embodiment has can be appropriately applied to other embodiments, respectively, and
The requirements in each embodiment can be appropriately replaced with each other.

[0046]

INDUSTRIAL APPLICABILITY The absorbent article of the present invention is capable of effectively exhibiting the performance of the surface sheet having excellent absorbency and texture, and is excellent in shape stability of the uneven portion during use. INDUSTRIAL APPLICABILITY The method for producing an absorbent article of the present invention is capable of efficiently and economically producing an absorbent article having excellent absorbency / texture.

[Brief description of drawings]

FIG. 1 is a schematic perspective view showing a sanitary napkin as an embodiment of the present invention.

FIG. 2 is a sectional view schematically showing a section taken along line XX of FIG.

FIG. 3 is a schematic perspective view showing a laminated sheet in an uneven region.

FIG. 4 is a cross-sectional view schematically showing a cross section taken along line YY of FIG.

FIG. 5 is a diagram showing a preferable formation pattern of a joint portion between a first layer and a second layer in an uneven region.

FIG. 6 is a diagram showing another formation pattern of a joint portion.

FIG. 7 is a schematic plan view showing a sanitary napkin as another embodiment of the present invention.

[Explanation of symbols]

10 Laminated sheet (top sheet) 1st layer 2 Second layer 3 joints 20 Sanitary napkins (absorbent articles) 30 Back sheet 40 absorber

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Hiroko Sugiura             Kao Stock Exchange 2606, Akabane, Kai-cho, Haga-gun, Tochigi Prefecture             Company research institute F-term (reference) 3B029 BB02 BB03 BF04                 4C003 BA02 BA08 GA03 GA05                 4C098 AA09 CC05 CC08 CC37 DD04                       DD10 DD22 DD24 DD25 DD26                       DD28

Claims (6)

[Claims] 1. A liquid-permeable top sheet, a liquid-impermeable back sheet, and a liquid-retaining absorber interposed between these sheets, wherein a large number of convex portions are regularly formed on the skin-contacting surface. In the absorbent article having a non-concave region in which a convex portion having a height lower than that of the convex and concave regions in the convex and concave regions formed in the concave or convex region is not formed, the concave and convex region is , A first layer arranged on the skin side and a second layer arranged on the absorber side are laminated and formed from a laminated sheet partially joined at a joining portion of a predetermined pattern, and a large number of the uneven areas are formed. The said convex part is an absorbent article in which the part other than the said junction part of a 1st layer deform | transforms into a convex shape by shrinkage | contraction of a 2nd layer. 2. The laminated sheet is arranged over both of the concavo-convex region and the non-concavo-convex region, and the area ratio of the joint portion of the first layer and the second layer in the concavo-convex region is the non-concave region. The absorbent article according to claim 1, which is lower than the area ratio of the joint portion of the first layer and the second layer in the uneven region. 3. The laminated sheet is arranged over both of the uneven area and the non-uneven area, the second layer in the uneven area is heat-shrinked, and the second layer in the non-uneven area is formed. The absorbent article of claim 1, wherein the layer is not heat shrunk. 4. The laminated sheet is arranged only in the concavo-convex area, the second layer in the concavo-convex area is heat-shrinked, and the second layer does not exist in the non-concave area. The absorbent article according to 1. 5. A liquid-permeable top sheet, a liquid-impermeable back sheet, and a liquid-retaining absorber interposed between these sheets, wherein a large number of convex portions are regularly formed on the skin-contacting surface. Formed unevenly region, and has a non-uneven region in which a convex portion having a height lower than the convex portion in the concave-convex region is formed or a convex portion is not formed, the concave-convex region is The first layer arranged on the skin side and the second layer arranged on the absorber side are laminated and are formed from a laminated sheet partially joined at a joint portion of a predetermined pattern, and a large number of sheets in the concavo-convex region are formed. As for the said convex part, the part other than the said junction part of a 1st layer is a 2nd
An absorbent article manufacturing method for manufacturing an absorbent article, which is formed by deforming into a convex shape due to contraction of a layer, comprising: a first layer disposed on the skin side and a second layer disposed on the absorbent body side. To obtain a laminated sheet by partially bonding the laminated sheet, the step of fixing the laminated sheet to the other member of the absorbent article as the surface sheet, and the laminated sheet before or after being fixed to the other member. A step of subjecting the second layer to heat shrinkage and deforming a portion other than the joint portion of the first layer into a convex shape by performing heat treatment, in joining the first layer and the second layer, First layer and second layer
A low-bonding region having a low area ratio of the bonding parts of the layers and a high-bonding region having a higher area ratio of the bonding parts of the first layer and the second layer than the low-bonding region are formed, A method for manufacturing an absorbent article, comprising forming a concavo-convex region and forming the non-concavo-convex region by the high bonding region. 6. A liquid-permeable top sheet, a liquid-impermeable back sheet, and a liquid-retaining absorber interposed between these sheets, wherein a large number of convex portions are regularly formed on the skin-contacting surface. Formed unevenly region, and has a non-uneven region in which a convex portion having a height lower than the convex portion in the concave-convex region is formed or a convex portion is not formed, the concave-convex region is The first layer arranged on the skin side and the second layer arranged on the absorber side are laminated and are formed from a laminated sheet partially joined at a joint portion of a predetermined pattern, and a large number of sheets in the concavo-convex region are formed. As for the said convex part, the part other than the said junction part of a 1st layer is a 2nd
An absorbent article manufacturing method for manufacturing an absorbent article, which is formed by being deformed into a convex shape by contraction of a layer, comprising: a first layer disposed on the skin side and a second layer disposed on the absorbent body side. To obtain a laminated sheet by partially bonding the laminated sheet, the step of fixing the laminated sheet to the other member of the absorbent article as the surface sheet, and the laminated sheet before or after being fixed to the other member. The method further comprises the step of partially heat-treating the second layer to heat-shrink it and deforming the portion of the first layer other than the joint portion into a convex shape. A method for manufacturing an absorbent article, wherein the uneven area is formed and the non-uneven area is formed by a portion of the laminated sheet which is not subjected to the heat treatment.