JP2012179220A - Absorbent article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thin absorbent article which can retain its form even upon absorption of large amounts of liquid, has multiple bending origins, and exhibits excellent fitting properties, flexibility and feel during wear.SOLUTION: The absorbent article comprising a liquid-permeable top sheet, a liquid-impermeable back sheet, and an absorbent core between the liquid-permeable top sheet and liquid-impermeable back sheet, wherein the absorbent article has prescribed compressed lines and prescribed compressed points formed by compressing at least the absorbent core.

Description

  The present invention relates to an absorbent article having a linear compressed portion and a dotted compressed portion.

Absorbent articles such as disposable diapers, sanitary napkins, etc. have improved their basic performance due to many years of technological development, and they have leaked after absorbing excrement such as urine and menstrual blood compared to before. Etc. have been reduced, and at present, there is a demand for further enhancement of functionality, for example, having a feeling of wearing close to underwear, for example, being thinner and having a good wearing feeling.
For example, in order to manufacture a thinner absorbent article, the basis weight of an absorbent body, a top sheet, a back sheet, etc. is reduced, and a pressing part is provided.

  As an absorptive article which has a pressing part, for example, in patent documents 1, an absorptive article which has a leakproof groove formed by embossing a top sheet and an absorption layer, ie, a linear pressing part, is mentioned. Are listed. [0014] In Reference 1 [0014], the function of the leakage prevention groove is to prevent the compressive stress deformation in the width direction of the napkin accompanying the opening / closing or walking of the foot from being transmitted to the central portion, that is, the leakage prevention groove. Acts as a “folding origin”.

  Patent Document 2 discloses a liquid-permeable sheet, a liquid-impermeable sheet, and an absorbent article having an absorbent body. The skin-contact surface side of the absorbent article has the liquid-permeable sheet and the absorbent article. In order to integrate the body, there is described an absorbent article in which pressing grooves are arranged at least at both side edges in the longitudinal direction of the absorber central region, and a plurality of point-like pressing parts are arranged at intervals. Has been.

JP 2002-65741 A JP 2010-148708

However, in the absorbent article described in Patent Document 1, the leak-proof groove formed by pressing acts as a “folding origin”, and the absorbent article is deformed to some extent in the width direction based on the two folding origins. However, it is difficult to deform in the longitudinal direction, and the feeling of wearing may be a problem. Further, when a large amount of liquid is absorbed, the form cannot be maintained, and problems such as twisting of the absorbent article and collapse of the absorbent body shape may occur.
Moreover, in the absorbent article of patent document 2, like patent document 1, the pressing groove formed by pressing acts as a “folding origin”, and the absorbent article is based on two folding origins. Although it can be deformed to some extent in the width direction, it is difficult to deform in the longitudinal direction, and the wearing feeling may be a problem. Further, in the absorbent article described in Patent Document 2, when a large amount of liquid is absorbed, the form of the absorbent article cannot be maintained, and the absorbent article may be twisted, the absorbent body may be deformed, or the like. .
Therefore, the present invention can maintain the form even when a large amount of liquid is absorbed, has a plurality of folding origins, has excellent fit, is soft, and has a good feeling of wearing. An object of the present invention is to provide an absorbent article.

As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that a liquid-permeable top sheet, a liquid-impermeable back sheet, the liquid-permeable top sheet, and a liquid-impermeable back sheet An absorbent article including an absorbent body between, wherein the absorbent article is formed by squeezing at least the absorbent body, and has a linear squeezed portion and a point squeezed portion, and The ratio of the total length of the linear compressed part to the length of the absorbent article in the longitudinal direction of the absorbent article is 5 to 20, and the thickness of the linear compressed part is the thickness of the non-compressed part. And within the range of 20 to 50%, the point pressing part has a number density of 3 to 40 pieces / cm ² based on the area of the absorber, and the point pressing The thickness of the part is in the range of 40 to 98% with respect to the thickness of the non-compressed part, and the linear pressure The thickness of the section is, the absorbent article, characterized in that less than the thickness of the point-like compressed parts, can solve the above problems, and have completed the present invention.

Specifically, the present invention relates to the following aspects.
[Aspect 1]
An absorbent article comprising a liquid-permeable top sheet, a liquid-impermeable back sheet, and an absorbent body between the liquid-permeable top sheet and the liquid-impermeable back sheet,
The absorbent article has at least a linear squeezed part formed by squeezing the absorbent body, and a point squeezed part,
The ratio of the total length of the linear compressed portion to the length of the absorbent article in the longitudinal direction of the absorbent article is 5 to 20, and the thickness of the linear compressed portion is that of the non-compressed portion. Within the range of 20-50% of the thickness,
The point-like compressed part has a number density of 3 to 40 / cm ² based on the area of the absorber, and the thickness of the point-like compressed part is relative to the thickness of the non-pressed part. In the range of 40-98%,
The thickness of the linear compressed portion is thinner than the thickness of the dotted compressed portion,
The above absorbent article.

[Aspect 2]
The absorptive article according to aspect 1, wherein the linear compressed portion and the dotted compressed portion are present in both side edge regions of the absorbent body in the longitudinal direction and a central region between the side edge regions.
[Aspect 3]
The absorbent article according to aspect 1 or 2, wherein the linear compressed portion and the dotted compressed portion are present in a front body trunk region, a crotch region, and a rear body trunk region of the absorber.

[Aspect 4]
The absorptive article according to any one of aspects 1 to 3, wherein the linear compressed portion is oriented in the longitudinal direction.
[Aspect 5]
A ratio of the absorber in the longitudinal direction to the bending resistance in a direction perpendicular to the longitudinal direction of the absorber is in a range of 0.4 to 2.5. The absorbent article as described in any one of 4.

[Aspect 6]
The absorbent article according to any one of aspects 1 to 5, wherein the ratio of the total area of the linear compressed portion to the area of the absorber is within a range of 4 to 20%.
[Aspect 7]
The ratio of the total area of the squeezed compressed parts to the area of the absorbent body is in the range of 5 to 30%, and the total area of the squeezed parts composed of the linear squeezed parts and the squeezed compressed parts is as described above. The absorptive article according to any one of aspects 1 to 6 whose ratio to the area of an absorber is 35% or less.

[Aspect 8]
The absorbent article according to any one of aspects 1 to 7, wherein both the longitudinal and width bending resistances of the absorbent article are 100 mN or less.
[Aspect 9]
At least one of the liquid permeable top sheet and the absorbent body is squeezed to form the linear squeezed portion and the point squeezed portion. The absorbent article as described in the description.

[Aspect 10]
After absorbing the liquid, the thickness of the linear squeezing part maintains the thickness in the range of 40 to 85% with respect to the thickness of the non-squeezing part. Absorbent articles.
[Aspect 11]
After the absorbent further contains a superabsorbent polymer and absorbs the liquid, the expansion coefficient of the superabsorbent polymer in the linear compressed part is smaller than the expansion coefficient of the superabsorbent polymer in the non-compressed part, The absorbent article as described in any one of aspects 1-10.

[Aspect 12]
The absorbent article according to any one of aspects 1 to 12, which is a disposable diaper or an incontinence pad.

  The absorbent article of the present invention is thin, can retain its form even when absorbing a large amount of liquid, has a plurality of folding origins, has excellent fit, and is soft, Excellent wearing feeling.

Drawing 1 is a figure showing one of the embodiments of the absorptive article of the present invention. Figure 2 is a sectional view enlarged view of X ₁ portion of the disposable diaper 1 shown in Figure 1, and in its sectional view taken along line X-X. Drawing 3A is a figure showing an example of a linear pressing part of an absorber which can be used for an absorptive article of the present invention. Drawing 3B is a figure showing an example of a linear pressing part of an absorber which can be used for an absorptive article of the present invention. FIG. 4A is a diagram illustrating an example of a point-like compressed portion of an absorbent body that can be used in the absorbent article of the present invention. FIG. 4B is a diagram illustrating an example of a point-like squeezed portion of an absorbent body that can be used in the absorbent article of the present invention.

The absorbent article of the present invention will be described in detail below.
Drawing 1 is a figure showing one of the embodiments of the absorptive article of the present invention. In FIG. 1, a disposable diaper is shown as a typical example of an absorbent article.

The disposable diaper 1 shown in FIG. 1 has a liquid-permeable top sheet 2, a liquid-impermeable back sheet 3, an absorbent body 4, a leak-proof wall 5, and a tape fastener 6. The disposable diaper 1 is divided into a front body trunk region W ₁ , a crotch region C, and a back body trunk region W ₂ . The disposable diaper 1 shown by FIG. 1 has the linear pressing part 8 and the dotted | punctate pressing part 9 which were formed by pressing the absorber 4. FIG. Reference numeral 7 denotes a skin contact surface.
In addition, in FIG. 1, although the linear pressing part 8 and the dotted | punctate pressing part 9 are under the top sheet 2, they are described with the continuous line for description.

In Figure 1, the compressed lines 8 and compressed points section 9, of the absorbent core 4, the side edge regions Z ₁ and Z ₃ in the longitudinal direction A of the disposable diaper 1, the central region Z ₂ between the both side edge regions And exist.
In the present specification, the side edge regions Z ₁ and Z ₃ , and the central region Z ₂ are respectively obtained when the absorbent body is divided into three equal parts in the longitudinal direction of the disposable diaper so that the width thereof is the same. , A region on the right side of the wearer, a region on the left side, and a region on the center.

In the disposable diaper 1 shown in FIG. 1, a plurality of corrugated linear pressing parts 8 are arranged in the longitudinal direction A and arranged so that valleys and peaks of adjacent linear pressing parts are almost in contact with each other. Yes.
In the disposable diaper 1 shown in FIG. 1, it is formed from 24 point-like compressed parts 9 in a substantially rhombic region formed by the peaks and valleys of the adjacent corrugated linear compressed parts 8. Seven regular hexagons are formed.

In the present specification, the “crotch region” means a region that forms an opening for allowing the wearer's leg to pass through during use, and the “front body torso region” refers to the front body in the torso region. This is a region to be formed, means a region on the front side of the crotch region, and the “torso region of the back body” is a region that forms the back body in the torso region, and is located on the back side of the crotch region. Means an area.
In the case of a pants-type disposable diaper, among the waistline gathers, the front body part is referred to as the front body trunk area, the back body part is referred to as the back body trunk area, and the area between them is referred to as the crotch area. be able to.

2A is an enlarged view of the X ₁ portion of the disposable diaper 1 shown in FIG. 1, and FIG. 2B is an XX cross section of the X ₁ portion of the disposable diaper 1 shown in FIG. FIG. A disposable diaper 1 shown in FIG. 2 (b) includes a liquid-permeable top sheet 2, a liquid-impermeable back sheet 3, and an absorbent body 4 between the top sheet 2 and the back sheet 3. In the disposable diaper 1 shown in FIG. 2 (b), two linear pressing parts 8 formed by pressing the core wrap 10 and the absorbent core 11 constituting the absorbent body 4, Four shape pressing parts 9 are shown, and the thickness t ₁ of the linear pressing part 8 is thinner than the thickness t ₂ of the point pressing part 9.

In the disposable diaper 1 shown in FIG. 1 and FIG. 2, a total of ten substantially corrugated linear pressing portions 8 having an inclination of about 40 ° with respect to the longitudinal direction A of the disposable diaper 1 are arranged. The ratio of the total length of the compressed portion 8 to the length L in the longitudinal direction A of the absorbent body 4 is about 13, and the thickness t ₁ of the linear compressed portion 8 is equal to the thickness t ₀ of the non-pressed portion. On the other hand, it is about 35%.
Moreover, in the disposable diaper 1 shown by FIG.1 and FIG.2, the dotted | punctate pressing part 9 has a number density of about 16 pieces / cm < ² > based on the total area of an absorber, and the dotted | punctate pressing part 9 of the thickness t ₂ is the thickness t ₀ of the non-compressed portion is about 55%.

  In the absorbent article of the present invention, the linear compressed part functions as a skeleton of the absorbent article, and the dotted compressed part functions as a folding start point of the absorbent article. In thin absorbent articles, the basis weight of top sheets, absorbent bodies, back sheets, etc. is small and tends to lose shape, but it is lost shape by arranging a predetermined amount of linear compressed parts as a skeleton. Difficult absorbent articles can be formed. Further, when the amount of the linear compressed portion increases, the absorbent article becomes hard and tends to be broken only from the linear compressed portion, but a predetermined amount of the dotted compressed portion is disposed on the absorbent article. Thereby, since a dotted | punctate pressing part becomes a bending start point of an absorbent article and an absorbent article can bend | fold in various directions, it is soft and a feeling of mounting | wearing becomes favorable.

  Drawing 3A and Drawing 3B are figures showing an example of a linear pressing part of an absorber which can be used for an absorptive article of the present invention. 3A (a) to (c) and FIGS. 3B (d) to (f) are views of the absorbent body as viewed from the top sheet side. In FIG. 3A (a), the eight linear pressing parts 8 are arrange | positioned in parallel with the longitudinal direction A of an absorber (absorbent article), and the absorber 4 of the total length of the linear pressing part 8 is shown. Is about 8.0 in the longitudinal direction A. Since the linear pressing part as shown in FIG. 3A (a) has a total of eight folding start points with respect to the width direction B of the absorbent article, the width of the absorbent article is flexible. Excellent and can follow the curve of the wearer's body.

In FIG. 3A (b), the 11 linear pressing parts 8 in total are arrange | positioned in parallel in the width direction B of an absorber (absorbent article), and the absorber 4 of the total length of the linear pressing part 8 is shown. Is about 5.5 in the longitudinal direction A. Since the linear pressing part as shown in FIG. 3A (b) has a total of 11 folding starting points with respect to the length direction A of the absorbent article, the length of the absorbent article is flexible. It is excellent in performance and can follow the curve of the wearer's body.
In FIG. 3A (c), the linear pressing part 8 which consists of 2 types of straight lines which incline about +/- 45 degrees from the longitudinal direction A of an absorber (absorbent article) and goes mutually orthogonally is arrange | positioned, and the linear pressing part 8 The ratio of the total length to the length of the absorbent body 4 in the longitudinal direction A is about 14. Since a linear pressing part as shown in FIG. 3A (c) has a plurality of folding start points in two directions, it can follow the curve of the wearer's body.

  In FIG. 3B (d), the linear pressing part 8 is arrange | positioned so that the honeycomb structure which consists of regular hexagons may be formed, and the length of the longitudinal direction A of the absorber 4 of the total length of the linear pressing part 8 is shown. The ratio to thickness is about 7.5. Since the linear pressing part as shown in FIG. 3B (d) has a plurality of folding start points in three directions, it can follow the curve of the wearer's body.

In FIG. 3B (e), it is a modification of the example of FIG. 3A (c), and the linear pressing part 8 is arrange | positioned so that it may not have the intersection of 2 types of pressing parts which mutually orthogonally cross. In FIG. 3B (e), the ratio of the total length of the linear pressing part 8 to the length of the absorbent body 4 in the longitudinal direction A is about 13.5. Since the linear pressing part as shown in FIG. 3B (e) does not have an intersection point between the linear pressing parts, which is easy to feel hardness, it is more comfortable to wear than the example described in FIG. 3A (c). There is a tendency to excel.
In FIG. 3B (f), it is a modification of the example of FIG. 3B (e), and the linear pressing part 8 does not have the intersection of two types of pressing parts orthogonal to each other, and it is in the direction of the longitudinal direction A. Since it arrange | positions continuously, the function as a skeleton of a linear pressing part can become stronger. In FIG. 3B (f), the ratio of the total length of the linear pressing portion 8 to the length of the absorbent body 4 in the longitudinal direction A is about 14 as in FIG. 3A (c).

  In the present invention, the ratio of the total length of the linear compressed portion to the length of the absorbent body in the longitudinal direction of the absorbent article is about 5 to about 20, preferably about 6 to about 18, More preferably from 8 to about 16, and even more preferably from about 9 to about 15. When the ratio is less than about 5, the function as a skeleton of the linear compressed portion is insufficient, the absorbent article may lose its shape when worn, particularly when absorbing a large amount of liquid, and the above When the ratio exceeds about 20, the function as a skeleton appears too strongly, the absorbent article becomes hard, and the wearing feeling tends to decrease.

In addition, the said ratio can be calculated | required by direct calculation from the length of the pressing pattern which forms a pressing part, or can be calculated | required by measuring the length of a linear pressing part in an actual absorber. In addition, in an actual absorber, when measuring the length of a linear pressing part, it can measure in the state which took out the absorber from the absorbent article and left still on the plane.
In addition, when the absorbent body is not substantially rectangular, for example, when it is substantially elliptical, the length of the absorbent body in the longitudinal direction is the length of the longest portion in the longitudinal direction of the absorbent article. For example, it means the major axis.

  In the absorbent article of the present invention, the thickness of the linear squeezed portion is about 20 to about 50%, preferably about 25 to about 45% with respect to the thickness of the non-pressed portion, and about More preferred is 30 to about 40%. When the thickness ratio is less than about 20%, the linear compressed portion tends to be too hard and the wearing feeling tends to decrease, and the core wrap is broken, and the superabsorbent polymer leaks and adheres to the wearer. There is a case. When the thickness ratio exceeds about 50%, the function of the linear compressed portion as a skeleton becomes insufficient, and the absorbent body is likely to be twisted or cracked in the absorbent article. However, it tends to lose its shape, particularly after absorbing the liquid.

  When the absorbent article of the present invention is a disposable diaper, for example, the thickness of the non-compressed portion is about 3 mm, the thickness of the linear compressed portion is about 1 mm, and the thickness ratio is about 33. %. In the disposable diaper, the thickness of the absorber is usually about 2 to about 8 mm.

In the absorbent article of the present invention, the thickness of the linear compressed portion, the point-shaped compressed portion, and the non-pressed portion is non-contact using a laser displacement meter before absorbing the liquid and after absorbing the liquid. Can be measured. Examples of the laser displacement meter include a high-precision two-dimensional laser displacement meter LJ-G series (model: LJ-G030) manufactured by Keyence Corporation.
By placing the sample on a horizontal measuring table and measuring the displacement from the measuring table, the thickness t _{1 of} the linear pressing part, the thickness t ₂ of the point pressing part, and the thickness t of the non-squeezing part ₀ can be measured. Incidentally, when the sample contains a backsheet or the like, separately measuring the thickness of the back sheet or the like, by subtracting from the measured values, the thickness t ₁ of the compressed lines to the thickness of the absorber, compressed points The thickness t _{2 of} the part and the thickness t ₀ of the non-compressed part can be obtained.

  Drawing 4A and Drawing 4B are figures showing an example of a dotted compression part of an absorber which can be used for an absorptive article of the present invention. FIG. 4A (a) is an example in which the point-like compressed parts 9 are regularly arranged in the vertical direction and the horizontal direction to form a square lattice 12. In the example of FIG. 4A (a), two kinds of broken lines 13 of the up-down direction and the left-right direction are formed by connecting the adjacent point-like compressed parts with the shortest distance, and the absorbent article is mainly used. It is thought that it is easy to bend along these two directions. In addition, it is considered that the actual ease of bending can be evaluated by evaluating the number of point-like compressed parts existing on a certain straight line as the number per unit length, that is, the linear density of the point-like compressed parts. .

  FIG. 4A (b) is an example in which the point-like compressed parts 9 are arranged in a staggered manner to form a rhombic lattice 12. In the example of FIG. 4A (b), two types of broken lines 13 are formed from the upper right to the lower left direction and the upper left to the lower right direction by connecting the adjacent point-like compressed parts with the shortest distance, and absorbability. The article is considered to be easily bent along these two directions.

  FIG. 4A (c) is an example in which the point-shaped compressed parts 9 are arranged at the apexes of a regular hexagon to form a regular hexagonal lattice 12. In the example of FIG. 4A (c), three types of broken lines 13 are formed by connecting the adjacent point-like compressed parts with the shortest distance, the vertical direction, the upper right to the lower left direction, and the upper left to the lower right direction. Thus, the absorbent article is considered to be easily bent along these three directions.

  FIG. 4B (d) is an example in which the point-like compressed parts 9 are arranged at the vertices of squares and regular octagons to form square lattices 12 and regular octagonal lattices 12. In the example of FIG. 4B (d), by connecting adjacent point-like compressed parts having the shortest distance, two types in the vertical direction, two types in the horizontal direction, from the upper right to the lower left direction, and from the upper left to the lower right direction A total of six types of broken lines 13 are formed, and the absorbent article is considered to be easily bent mainly along these six directions.

  4B (e) and 4B (f) are further improvements of FIGS. 4A (c) and 4B (d), respectively. In FIG. 4B (e) and FIG. 4B (f), since it becomes a guide at the time of bending by making the shape of the dotted | punctate pressing part 9 into the shape which extends in the direction of the broken line 13, along the broken line 13, The absorbent body, and thus the absorbent article, is more likely to bend.

In the absorbent article of the anti-invention, when the point-like compressed parts are regularly arranged as shown in FIGS. 4A and 4B, for example, the point-like compressed parts are uniformly distributed, and bendability, absorbability, etc. Unevenness is less likely to occur.
In addition, in this specification, when the absorber is observed from the top sheet side, the “spot-shaped compressed part” means that the major axis of the compressed part is not more than three times the minor axis. A material having a major axis exceeding three times the minor axis is referred to as a “linear pressing part” to be distinguished.
The shape of the point-like compressed portion is not particularly limited, but for example, in addition to the circles shown in FIGS. 4A (a) to 4A (c) and 4B (d), an ellipse, a triangle, for example, a regular triangle, Examples include a square, a rectangle, a regular pentagon, a star, a heart, and the figures described in FIGS. 4B (e) and 4B (f).

In the absorbent article of the present invention, the point-like compressed portion has a number density of about 3 to about 40 pieces / cm ^{2 and} a number of about 5 to about 30 pieces / cm ² based on the total area of the absorbent body. Preferably, it has a density and more preferably has a number density of about 10 to about 20 / cm ² . When the number density is less than about 3 pieces / cm ² , the number of folding start points of the absorber is insufficient, the absorbent article may become hard, and the number density exceeds about 40 pieces / cm ² . Then, the entire absorbent body is compressed, the rigidity becomes high, the wearing feeling is inferior, and the liquid absorption ability tends to be lowered.

  In the absorbent article of the present invention, the thickness of the point-like compressed part is about 40 to about 98%, preferably about 45 to about 90%, and about More preferred is 50 to about 80%. When the thickness ratio is less than about 40%, hardness appears in the point-like compressed part itself, which leads to the hardness of the entire absorbent body, and the wear feeling tends to decrease, and the thickness ratio is about 98%. Exceeding the value tends to not function as a fold starting point.

  When the absorbent article of the present invention is a disposable diaper, for example, the thickness of the non-compressed portion is about 3 mm, the thickness of the point-like compressed portion is about 2 mm, and the thickness ratio is about 67. %. In addition, as mentioned above, in the disposable diaper, the thickness of the absorber is usually about 2 to about 8 mm.

  Moreover, the absorbent article of this invention WHEREIN: The thickness of a linear pressing part is thinner than the thickness of a dotted | punctate pressing part. Since the linear compressed portion functions as a skeleton, it needs to be compressed with a constant pressure and its thickness needs to be thin, but the point-shaped compressed portion only needs to function as a fold starting point, and with a pressure that functions as a skeleton. This is because it does not need to be squeezed. Rather, when it is squeezed at such a pressure that it functions as a skeleton, the rigidity of the point-like squeezed part increases and the liquid absorption capacity decreases.

In the absorbent article of the present invention, it is preferable that the linear squeezed portion be present in both side edge regions in the longitudinal direction and a central region between both side edge regions of the absorbent body. This is because the linear squeezed portion functions as a skeleton in the absorbent article and therefore preferably exists evenly over the entire range of the absorbent body. In particular, in order to prevent the absorber from falling off from the absorbent article, it is preferable that the linear compressed portion is present in the central region in the longitudinal direction of the absorber.
For the same reason, it is preferable that the linear squeezed portion exists in the trunk region of the front body, the crotch region, and the trunk region of the back body of the absorber.

In the absorbent article of the present invention, it is preferable that the point-like compressed portion is present in both side edge regions in the longitudinal direction and the central region between both side edge regions of the absorbent body, like the linear pressed portion. This is because the point-like squeezed portion functions as a fold starting point in the absorbent article, and therefore, it is preferable that the point-like squeezed portion exists uniformly in the entire range of the absorbent body in order to impart flexibility to the absorbent body.
For the same reason, it is preferable that the linear squeezed portion exists in the trunk region of the front body, the crotch region, and the trunk region of the back body of the absorber.

  Moreover, in the absorbent article of the present invention, the ratio of the absorbent body in the longitudinal direction of the absorbent article to the absorbent body in the width direction is about 0.4 to about 2.5. Preferably within the range of about 0.5 to about 2.2, and more preferably within the range of about 0.7 to about 1.8. This is because it is preferable to have the same degree of flexibility in both the longitudinal direction and the width direction of the absorbent article.

  In the absorbent body used in the absorbent article of the present invention, the longitudinal and width bending resistance of the absorbent article is determined by specific embodiments of the absorbent article, such as an adult disposable diaper, a baby disposable diaper, Depending on the sanitary napkin, for example, night sanitary napkins, daytime sanitary napkins, etc., in the case of disposable diapers for babies, both the longitudinal and width bending resistances are about 100 mN or less. Preferably, it is about 90 mN or less, and more preferably about 80 mN or less. When the bending resistance of the absorbent article in the longitudinal direction and the width direction is both about 100 mN or less, the disposable diaper can have flexibility in both the longitudinal direction and the width direction.

In addition, the said bending resistance can be measured as follows using the bending resistance measuring device (Taber type | mold step stiffness tester) tester by Nisshin Kikai Co., Ltd.
1. Cut the absorber with a scissor or press cutter into a size of 38 mm x 70 mm (when measuring the bending resistance in the longitudinal direction, cut the absorbent so that the longitudinal direction of the absorber is 70 mm) Form.
2. The sample is fixed between jigs of a bending resistance tester, and the screws on both sides are tightened loosely so that the sample does not fall.
3. Adjust the knob on the bottom to match the rotation device “0” with the load scale “0”.
4). Use the screws at both ends of the roller to keep the roller at a distance (about 0.5 mm) that touches or does not touch the sample.
5. Tilt the switch to the right and turn the sample rotation device to the right. When the 15-degree marking (left side) matches the pendulum pointer, the switch is returned to stop the rotation, and the load scale is read.
6). Similarly, when the switch is tilted to the left and the sample rotating device is turned to the left, when the 15-degree marking (right side) matches the pendulum pointer, the switch is returned to stop the rotation, and the load scale is read.
7). The bending resistance is calculated according to the following formula.
Bending softness = (right load scale + left load scale) / 2 × weight value / 1000 × 9.807
The measurement is performed 10 times, and the average value is adopted as the bending resistance.

  In the absorbent article of the present invention, the ratio of the total area of the linear compressed portion to the area of the absorbent body is preferably in the range of about 4 to about 20%, and in the range of about 6 to about 18%. More preferably, and more preferably in the range of about 7 to about 15%. When the ratio is less than about 4%, the function as a skeleton tends to be insufficient, and when the ratio is more than about 20%, the ratio of the region that absorbs liquid in the absorber is reduced, and absorption. Performance may be affected.

  Moreover, in the absorbent article of the present invention, the width of the linear compressed portion is preferably in the range of about 0.5 to about 2.0 mm. When the width | variety of a linear pressing part exceeds about 2.0 mm, the hardness of each linear pressing part will be conspicuous and there exists a tendency for a tactile sensation to fall. On the other hand, when the width of the linear compressed portion is less than about 0.5 mm, the function as a skeleton becomes insufficient, and further, when forming the compressed portion, it is necessary to sharpen the shape of the pin forming the compressed portion. May occur and the absorber may be broken during pressing.

  In the absorbent article of the present invention, the ratio of the total area of the point-like compressed parts to the area of the absorbent body is preferably in the range of about 5 to about 30%, and in the range of about 6 to about 25%. And more preferably within the range of about 7 to about 20%. When the ratio is less than about 5%, the number of folding start points is small and the flexibility tends to be inferior. When the ratio is more than about 30%, the volume of the absorbent body is reduced and the absorption capacity is affected. May appear.

  In addition, the ratio of the total area of the compressed portion including the linear compressed portion and the point-shaped compressed portion to the area of the absorbent body is preferably about 35% or less, more preferably about 30% or less, and about More preferred is 25% or less, and most preferred is about 20% or less. When the ratio exceeds about 35%, the volume of the absorber is reduced, which may affect the absorption capacity.

In the absorbent article of the present invention, the individual area of the point-like compressed portion is preferably about 9 mm ² or less, more preferably about 4 mm ² or less, and further preferably about 2 mm ² or less. . The reason is that even if the area is small, it functions as a folding start point, and when the area is large, the absorbent body tends to be hard, the absorptivity decreases, and the like.

In addition, in this specification, the area of a linear pressing part and a point pressing part means the opening part area of a linear pressing part, and the opening part area of a point pressing part, respectively. If the said opening part area is demonstrated using FIG.2 (b), the part which is in contact with the top sheet 2 among the linear pressing parts 8 is an opening part of the linear pressing part 8, The area is opening. It is a partial area. Similarly, the part which is in contact with the top sheet 2 among the dotted | punctate pressing parts 9 is an opening part of the dotted | punctate pressing part 9, The area is an opening part area.
Similarly, the width | variety of a linear pressing part means the opening part width | variety of a linear pressing part.

  In the absorbent article of the present invention, the thickness of the linear compressed portion after absorbing the liquid is in the range of about 40 to about 85% of the thickness of the non-pressed portion after absorbing the liquid. It is preferred to maintain a thickness in the range of about 50 to about 80%, more preferably a thickness in the range of about 60 to about 75%. This is because the linear compressed portion needs to function as a skeleton even after absorbing the liquid.

In addition, the thickness of the linear pressing part after liquid absorption can be measured on condition of the following.
The sample is cut into a size of 10 mm × 10 mm so as to include both a linear compressed part and a non-compressed part, placed on a horizontal measuring table, and 200 μL of artificial urine is dropped using a pipette. After 2 minutes, the displacement from the measurement table is measured with respect to the linear compressed part and the non-compressed part. The displacement can be measured using the laser displacement meter described above. In addition, when the size of a linear pressing part is 10 mm x 10 mm or more, two types, the sample of a linear pressing part and the sample of a non-squeezing part, are prepared.
The artificial urine can be produced by dissolving 200 g of urea, 80 g of sodium chloride, 80 g of magnesium sulfate, 8 g of calcium chloride, and about 1 g of pigment: Blue No. 1 in 10 L of ion-exchanged water.

  In the absorbent article of the present invention, the absorber can further include a superabsorbent polymer. When the absorber contains a superabsorbent polymer, the expansion coefficient of the superabsorbent polymer in the linear compressed part after absorbing the liquid is the same as that of the superabsorbent polymer in the non-squeezed part after absorbing the liquid. It is preferable that it is smaller than an expansion coefficient. This is because the linear compressed portion needs to function as a skeleton even after absorbing the liquid.

The expansion coefficient can be measured as follows.
The sample is cut into a size of 10 mm × 10 mm so as to include both a linear compressed part and a non-compressed part, placed on a horizontal measuring table, and 200 μL of artificial urine is dropped using a pipette. Two minutes later, the sample is subjected to a treatment such as vapor deposition, and a cross-sectional image of the cross-section is taken with an electron microscope of Real Surface View VE7800 manufactured by KEYENCE. From the image, measure the diameter of at least 100 superabsorbent polymer particles present immediately below the linear compressed part, measure at least 100 diameters of the superabsorbent polymer particles located in the non-compressed part, and measure the linear compressed part. The expansion coefficient is calculated by dividing the average value of the diameter of the superabsorbent polymer particles present immediately below the diameter by the average value of the diameter of the superabsorbent polymer particles located in the non-pressed portion. In addition, when the size of a linear pressing part is 10 mm x 10 mm or more, two types of samples, the sample of a linear pressing part and the sample of a non-squeezing part, are prepared. If it is difficult to measure 100 superabsorbent polymer diameters with a single sample, a plurality of samples are prepared.

In addition, until now, although the linear pressing part and the dotted | punctate pressing part have illustrated the embodiment currently formed by pressing the absorber containing an absorptive core and a core wrap, and the superabsorbent polymer by necessity, line | wire The shape pressing part and the point pressing part are not limited to these, and the above-described linear pressing part and the point pressing part are formed by pressing the liquid-permeable top sheet and the absorbent body. May be.
Moreover, when an absorbent article contains a second sheet between a top sheet and an absorber, the said linear pressing part and a dotted | punctate pressing part are obtained by pressing a second sheet and an absorber. Or the top sheet, the second sheet, and the absorbent body may be squeezed to form the linear squeezed portion and the point squeezed portion.

As the liquid-permeable top sheet used in the present invention, those usually used in the art can be selected without particular limitation, and examples thereof include non-woven fabrics, woven fabrics, and all or Examples thereof include a resin film that is partly liquid permeable and formed with a large number of liquid permeable holes, and a net-like sheet having a large number of meshes. Examples of the nonwoven fabric include spunlace nonwoven fabric formed from cellulose fibers such as rayon, synthetic resin fibers, and the like, and air-through nonwoven fabric formed from the synthetic resin fibers.
Examples of the resin film and net-like sheet include those formed from polypropylene, polyethylene, polyethylene terephthalate, and the like.

As the liquid-impermeable back sheet used in the present invention, those usually used in the art can be used without particular limitation, and examples thereof include a low-density polyethylene sheet.
In the absorbent article of the present invention, the leakage barrier is an optional element and, if present, can be similar to the topsheet.

As an absorptive core which comprises the said absorber, what is normally used in this technical field can be used without a restriction | limiting in particular, For example, a ground pulp, a chemical pulp, a cellulose fiber, rayon, acetate, etc. Artificial cellulose fibers, synthetic fibers, and sheets formed from these, such as air-laid sheets and through-air nonwoven fabrics. The absorbent core may further include a superabsorbent polymer, for example, a starch-based, acrylic acid-based, amino acid-based particulate or fibrous polymer.
As a core wrap which comprises the said absorber, what is normally used in this technical field can be used without a restriction | limiting in particular, For example, a tissue, a hydrophilic nonwoven fabric, etc. are mentioned.

  Examples of the absorbent article of the present invention include disposable diapers, incontinence pads, sanitary napkins, panty liners, etc., but the absorbent article of the present invention is capable of absorbing a large amount of liquid. In particular, disposable diapers and incontinence pads are preferred embodiments because they can retain form.

The absorptive article of the present invention can be manufactured as follows, for example.
1. The absorbent core containing pulp, superabsorbent polymer or the like as the absorbent core is packaged with a tissue (core wrap) coated with a hot melt adhesive.
2. The package is passed through a pair of rolls having a pressing pattern (top sheet side) and a flat surface (back sheet side) to form a pressing portion.
In addition, it is preferable that the said pressing pattern has both the pattern of a linear pressing part, and the pattern of a point pressing part, and forms a linear pressing part and a point pressing part simultaneously. It is because the shape of both pressing parts can be formed without wrinkles or crushing.
In addition, when a linear pressing part and a dotted | punctate pressing part are divided and formed in two times, the shape of the pressing part formed in the 1st time tends to lose | disappear at the time of the 2nd pressing.
The difference in the depth between the linear compressed portion and the dotted compressed portion can be achieved by changing the height of the pins forming the compressed portion.

Hereinafter, although an example is given and the present invention is explained, the present invention is not limited to these examples.
[Example 1]
[Total length of linear compression section]
The basis weight of 250 g / m ² of pulp, by covering with a basis weight of 17 g / m ² tissue, to produce an absorbent body prior to expression (about 11cm × about 35 cm, a thickness of about 3.0 mm), the absorber No. It was set to 1. Next, one or a plurality of linear pressing parts extending in the longitudinal direction as shown in FIG. 3A (a) are formed in the absorbent body No. 1. 2-No. 8 was formed. Absorber No. 2-No. 8 differs in the number of linear pressing parts, and the ratio of the total length of the linear pressing parts to the length in the longitudinal direction of the absorbent body is different. In addition, as for all the linear pressing parts, the thickness was about 1 mm and the width | variety was about 1 mm.

For example, the absorber No. Since the number of the linear pressing parts is 5, the ratio of the total length of the linear pressing parts to the length in the longitudinal direction of the absorbent body is 5.
Absorber No. 1-No. 8, a top sheet and a back sheet are pasted, respectively. 1-No. 8 and absorbent article no. 1-No. Regarding No. 8, the shape retention of the absorber was tested, and the relationship between the ratio and the function as a skeleton was confirmed. The results are shown in Table 1.

In addition, the form retainability of the absorbent article was tested as follows.
1. The absorbent body to be tested is affixed to an L-size disposable diaper for children and worn by a subject (child).
2. After 10 minutes, with the subject wearing, in a standing position, 200 cc of water warmed to about 37 ° C. is dropped into the disposable diaper from the ventral side through the tube.
The dripping is performed at the center of the absorber.
3. After 30 minutes, the disposable diaper is removed from the subject, and the shape retention of the absorber is visually evaluated based on the following criteria.
4). A similar test is conducted with a total of 5 subjects and is evaluated comprehensively.
The subject wearing the disposable diaper is not limited in operation, but the subject who has been sleeping or sitting on a chair for most of 30 minutes is excluded from the evaluation.

[Evaluation criteria]
○: Absorber is not separated into two, and is not cracked. Δ: Absorber is not separated into two, but is cracked. ×: Absorber is separated into two or more. Have

  From Table 1, it is suggested that when the ratio is about 5 or more, the form of the absorbent body is maintained during use.

[Example 2]
As shown in FIG. 1, a pulp having a basis weight of 250 g / m ² is sprayed with an acrylic acid-based superabsorbent polymer so as to have a basis weight of 220 g / m ² and wrapped with a tissue having a basis weight of 17 g / m ² . The absorbent body No. is formed by forming a linear compressed portion and a dotted compressed portion. 6 was produced.
The said linear pressing part and the dotted | punctate pressing part shall be 0.7 mm in height of the pin for linear pressing parts, shall be 0.2 mm in height of the pin for dotted pressing parts, and for linear pressing parts The clearance from the tip of the pin to the anvil roll was 0.3 mm, and the oil pressure was 3 Mpa.

  The width of the formed linear pressing part is about 1 mm, and the lengths of the two diagonal lines of the rhomboid unit cell formed from the linear pressing part are 25 mm (longitudinal direction) and 19 mm (width direction). there were. Moreover, the formed dotted | punctate pressing part was about 1.1 mm in diameter, and the regular hexagon side was about 2 mm. Absorber No. Table 2 shows the thicknesses of the 6 linear compressed parts, the dotted compressed parts, and the non-compressed parts.

[Comparative Example 1]
Acrylic acid superabsorbent polymer is sprayed on a pulp having a basis weight of 250 g / m ^{2 so} that the basis weight is 220 g / m ^2, and these are wrapped with a tissue having a basis weight of 17 g / m ² . Absorber No. having a linear squeezed part as shown. 7 was produced. Absorber No. Table 2 shows the thicknesses of 7 linear compressed parts and non-compressed parts.

[Comparative Example 2]
Acrylic acid superabsorbent polymer is sprayed onto a pulp having a basis weight of 250 g / m ^{2 so} that the basis weight is 220 g / m ^2, and these are wrapped with a tissue having a basis weight of 17 g / m ² . Absorber No. having a linear squeezed part as shown. 8 was produced. Absorber No. Table 2 shows the thicknesses of the 8 linear compressed parts and the non-compressed parts.

[Example 3]
[Bending softness]
Using a bending resistance tester (Taber-type step stiffness tester) manufactured by Nisshin Kikai Co., Ltd., the absorber No. The bending resistance of 6-8 was measured. The results are shown in Table 3.

  It can be seen that the absorbent body manufactured in Example 2 has low bending resistance in the longitudinal direction and the width direction, is flexible in the longitudinal direction and the width direction, and the difference therebetween is also small.

[Example 4]
[Thickness of linear pressing part and linear pressing part]
An unsqueezed absorbent body (2.5 mm, 3.0 mm, and 3.5 mm) having three thicknesses was prepared by wrapping pulp having different basis weights with a tissue having a basis weight of 17 g / m ² . Next, by forming a linear compressed portion and a dotted compressed portion having a shape as shown in FIG. 1-33 were formed. Absorber No. 1-33 have the linear pressing part and the point-like pressing part of the shape as shown in FIG. 1, but their thicknesses are different.

Absorber No. 1 to 33, the shape retention, tactile sensation, and bendability of the absorber were evaluated. The results are shown in Table 4.
The form retention of the absorbent body was evaluated in the same manner as in Example 1, and the tactile sensation and the bending property were sensory evaluated in two stages of ◯ or ×.

  As mentioned above, it is preferable that the thickness of a linear pressing part exists in the range of 20 to 50% with respect to the thickness of a non-pressing part, and the thickness of a dotted | punctate pressing part is the thickness of a non-squeezing part. It can be seen that the thickness is preferably in the range of 40 to 98%, and that the thickness of the linear compressed portion is preferably smaller than the thickness of the dotted compressed portion.

DESCRIPTION OF SYMBOLS 1 Disposable diaper 2 Top sheet 3 Back sheet 4 Absorber 5 Leak-proof wall 6 Tape fastener 7 Skin contact surface 8 Linear pressing part 9 Dotted pressing part 10 Core wrap 11 Absorbing core 12 Grid 13 Polygonal line A Longitudinal direction B Width direction W ₁ Torso area of the front body W ₂ Torso area of the back body C Crotch area

Claims (12)

An absorbent article comprising a liquid-permeable top sheet, a liquid-impermeable back sheet, and an absorbent body between the liquid-permeable top sheet and the liquid-impermeable back sheet,
The absorbent article has a linear squeezed part formed by squeezing at least the absorber, and a point squeezed part,
The ratio of the total length of the linear compressed portion to the length of the absorbent article in the longitudinal direction of the absorbent article is 5 to 20, and the thickness of the linear compressed portion is that of the non-compressed portion. Within the range of 20-50% of the thickness,
The dotted compression part has a number density of 3 to 40 / cm ² based on the area of the absorber, and the thickness of the dotted compression part is relative to the thickness of the non-squeezed part. In the range of 40-98%,
The thickness of the linear compressed portion is thinner than the thickness of the dotted compressed portion,
The absorbent article.   The absorptive article according to claim 1 in which said linear pressing part and point-like pressing part exist in the both-sides marginal field of said longitudinal direction of said absorber, and the central field between said both-sides marginal field.   The absorptive article according to claim 1 or 2 in which said linear compression part and dotted compression part exist in a trunk region of a front body, a crotch region, and a trunk region of a back body of said absorber.   The absorbent article as described in any one of Claims 1-3 in which the said linear pressing part is orientating in the said longitudinal direction.   The ratio of the bending resistance of the absorbent body in the longitudinal direction to the bending resistance of the absorbent body in a direction perpendicular to the longitudinal direction is in the range of 0.4 to 2.5. The absorbent article as described in any one of -4.   The absorbent article as described in any one of Claims 1-5 in which the ratio with respect to the area of the said absorber of the total area of the said linear pressing part exists in the range of 4-20%.   The ratio of the total area of the squeezed compressed parts to the area of the absorbent body is in the range of 5 to 30%, and the total area of the squeezed parts composed of the linear squeezed parts and the squeezed compressed parts, The absorptive article according to any one of claims 1 to 6 whose ratio to the area of an absorber is 35% or less.   The absorbent article as described in any one of Claims 1-7 whose both the longitudinal direction of the said absorbent body and the bending resistance of the said absorbent article are 100 mN or less.   At least the liquid permeable top sheet and the absorber are squeezed to form the linear squeezed portion and the point-like squeezed portion. Absorbent article as described in.   After absorbing the liquid, the thickness of the linear squeezed part maintains a thickness in the range of 40 to 85% with respect to the thickness of the non-squeezed part. The absorbent article as described.   After the absorbent further includes a superabsorbent polymer and absorbs the liquid, the coefficient of expansion of the superabsorbent polymer in the linear compressed part is smaller than the coefficient of expansion of the superabsorbent polymer in the non-squeezed part, The absorptive article according to any one of claims 1 to 10.   The absorbent article according to any one of claims 1 to 11, which is a disposable diaper or an incontinence pad.

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