JP6257511B2 - Absorbent articles - Google Patents

Description

  The present disclosure relates to absorbent articles.

  An absorbent article comprising a liquid-permeable layer, a liquid-impermeable layer, and the absorbent body provided between the liquid-permeable layer and the liquid-impermeable layer as the absorbent article, A body including thermoplastic resin fibers and cellulosic water-absorbing fibers, wherein at least a part of the thermoplastic resin fibers are exposed on the surface of the absorbent on the liquid-permeable layer side; and A second portion exposed on the surface of the absorber on the liquid-impermeable layer side; a first portion and a connecting portion that connects the second portion; and in the thickness direction of the absorber. An absorbent article characterized by a tensile strength of 100 Pa or more is known (Patent Document 1).

  In patent document 1, the thermoplastic resin fiber which has a specific structure functions as a frame | skeleton for hold | maintaining a cellulosic water absorption fiber, and is compatible with the softness and intensity | strength of an absorber.

International Publication No. 2014/199714 Pamphlet

The absorbent body described in Patent Document 1 and the absorbent article including the absorbent body have improved wearing feeling due to the softness of the absorbent body. However, in an absorbent article having excellent softness, the absorbent body can be freely deformed following the movement of the wearer, while the liquid-permeable layer is difficult to deform following the movement of the wearer. There is a possibility that wrinkles generated during deformation remain on the surface of the permeable layer. If wrinkles remain on the surface of the liquid-permeable layer, it is not preferable from the viewpoint of aesthetics, and the wearer may feel anxiety such that the absorbed body fluid leaks outside through the wrinkles.
Therefore, this indication aims at providing the absorbent article which is soft and does not remain wrinkles easily.

The present disclosure includes a liquid permeable layer having a skin contact surface, a liquid impermeable layer, the liquid permeable layer, and an absorbent body between the liquid impermeable layer, a longitudinal direction and a width. An absorbent article having a direction, wherein the liquid permeable layer has a plurality of recesses in the skin contact surface, and the absorbent body is composed of a cellulosic water absorbent fiber and the cellulosic water absorbent fiber. A thermoplastic resin fiber having a long fiber length, at least a part of the thermoplastic resin fiber of the absorbent body is bonded to the liquid-permeable layer, and the absorbent article is 3 to 25 mN. -The absorbent article which has the bending rigidity value of the said longitudinal direction by the KES method of m < ² > / m was discovered.

  The absorbent article of the present disclosure is soft and hardly wrinkles remain.

FIG. 1 is a plan view of an absorbent article 1 according to the first embodiment. FIG. 2 is a plan view of the second liquid-permeable layer 9 and the absorber 3 in the first embodiment. 3 is an end view taken along the line III-III in FIG. FIG. 4 is an end view taken along the IV-IV end face of FIG. FIG. 5 is an end view of the VV end face of FIG. FIG. 6 is a diagram for explaining a method for measuring tensile strength. Drawing 7 is a figure for explaining a manufacturing method of an absorber of an absorptive article according to one of the embodiments of this indication.

[Definition]
・ "Recess"
In the present specification, the “concave portion” means a region having a lower height than the reference plane. Examples of the reference surface include the surface (skin contact surface) of the liquid permeable layer.
The reference surface may be referred to as a convex portion compared to the concave portion.

・ "Exposure"
As used herein, “exposed” with respect to thermoplastic resin fibers means that the thermoplastic resin fibers are present on one surface or the other surface of the absorbent body.

・ "Average fiber length"
In the present disclosure, the average fiber lengths of thermoplastic resin fibers and cellulose-based water-absorbing fibers other than pulp fibers, for example, regenerated cellulose fibers and semi-synthetic fibers, are defined in “Appendix A” of JIS L 1015: 2010. Measurement is performed according to “A7.1.1 Method of measuring length of individual fibers on glass plate with A method (standard method) scale” in “A7.1 Measurement of fiber length”.
The above method is a test method corresponding to ISO 6989 issued in 1981.

・ "Average fiber length"
In the present disclosure, the average fiber length of the pulp fiber means a weight-weighted average fiber length, and Kajaani Fiber Lab fiber properties (off-line) manufactured by Metso Automation Co., Ltd. [kajaani FiberLab fiber properties (off-line)]. Means the L (w) value measured by

Hereinafter, the absorbent article of the present disclosure will be described.
FIG. 1 is a plan view of an absorbent article 1, specifically a sanitary napkin, according to one of the embodiments of the present disclosure (first embodiment). FIG. 2 is a plan view of the second liquid-permeable layer 9 (specifically, the auxiliary sheet) and the absorber 3 in the first embodiment, and FIG. 3 is an end surface at the III-III end surface of FIG. 4 is an end view at the IV-IV end face of FIG. 2, and FIG. 5 is an end view at the VV end face of FIG. 2 to 5 are schematic diagrams, and for the sake of explanation, the thermoplastic resin fibers 22 are thick and long, and the cellulosic water-absorbing fibers 21 are thinner and shorter than the thermoplastic resin fibers 22. 2-5 do not reflect their actual length and thickness. Moreover, the thickness of each component of the absorbent article 1 does not reflect the actual one.

  As shown in FIG. 1, the absorbent article 1 according to the first embodiment includes a first liquid-permeable layer 2 (specifically, a liquid-permeable top sheet), an absorber 3, and a liquid-impermeable material. A layer (specifically, a liquid-impermeable back sheet) (not shown), and has a longitudinal direction L and a width direction W.

  In the first embodiment, as shown in FIG. 1, the first liquid-permeable layer 2 has a plurality of recesses 5 on the skin contact surface 4, more specifically, the length of the absorbent article 1. A plurality of grooves extending in the direction L are provided. The plurality of recesses 5 extend in a predetermined direction, specifically, the longitudinal direction L of the absorbent article 1 and are arranged at a predetermined pitch in the width direction W of the absorbent article 1.

  Furthermore, the absorbent article 1 in the first embodiment is formed by embossing the first liquid permeable layer 2, the second liquid permeable layer 9, and the absorber 3, as shown in FIG. The first embossed portion 6 is provided.

The absorbent article 1 in the first embodiment includes a side sheet 7 and a seal portion 8 formed by sealing an end portion of the absorbent article 1.
In addition, in this indication, a side sheet and a seal part are arbitrary, and an absorptive article according to another embodiment of this indication does not have a side sheet and / or a seal part.

  As shown in FIG. 2, the absorbent article 1 in the first embodiment is formed by embossing the absorber 3 and the second liquid permeable layer 9, and a plurality of second embossed portions arranged in a staggered manner. 10 is included.

  In the first embodiment, the absorbent body 3 includes a cellulosic water absorbent fiber 21 and a thermoplastic resin fiber 22 having a fiber length longer than that of the cellulosic water absorbent fiber 21, as shown in FIG. Further, at least a part of the thermoplastic resin fiber 22 includes a first portion 22a exposed on one surface 23 of the absorber 3, a second portion 22b exposed on the other surface 24 of the absorber 3, and a first portion 22b. And a connecting portion 22c for connecting the first portion 22a and the second portion 22b.

  In the first embodiment, as shown in FIG. 4, at least a part of the thermoplastic resin fibers 22 of the absorbent body 3 is formed on the liquid permeable layer, specifically, the second liquid permeable layer 9 and the second liquid permeable layer 9. It is joined via the embossed part 10. Specifically, in the second embossed portion 10, a part of the thermoplastic resin fiber 22 of the absorbent body 3 is fused to the second liquid permeable layer 9, thereby the thermoplastic resin fiber 22 of the absorbent body 3. A part is bonded to the second liquid-permeable layer 9. Furthermore, at least a part of the thermoplastic resin fibers 22 of the absorbent body 3 is second liquid permeable through an adhesive portion (not shown) disposed between the second liquid permeable layer 9 and the absorbent body 3. Bonded to layer 9.

  As shown in FIG. 5, in the first embossed portion 6, a part of the thermoplastic resin fiber 22 of the absorbent body 3 is fused to the second liquid-permeable layer 9, so that the thermoplasticity of the absorbent body 3 is obtained. A part of the resin fiber 22 is bonded to the second liquid permeable layer 9.

In the first embodiment, as shown in FIG. 5, the second liquid permeable layer 9 is a layer adjacent to the skin surface side of the second liquid permeable layer 9 with the adhesive portion 31 in between, that is, The first liquid permeable layer 2 is joined. The absorbent body 3 is bonded to a layer adjacent to the clothing side of the absorbent body 3, that is, the liquid-impermeable layer 33 with the adhesive portion 32 interposed therebetween.
Further, in the first embodiment, as shown in FIG. 5, the absorbent article 1 has a fixing portion 34 for fixing the absorbent article 1 to the clothing on the clothing side surface of the liquid-impermeable layer 33. Have.

The absorbent article of the present disclosure, the 3~25mN · m ² / m, by KES method, has a longitudinal flexural rigidity, and more preferably preferably 4~20mN · m ² / m, 5~15mN -It has a bending stiffness value in the longitudinal direction by the KES method of m ² / m. By doing so, a wearer becomes easy to feel softness to an absorptive article at the time of wear.

The absorbent article of the present disclosure preferably has the above bending stiffness value at the center in the longitudinal direction of the absorbent article. This is because, in general, an absorbent article generally has a high bending rigidity value at the center in the longitudinal direction.
The absorbent article of the present disclosure preferably has the bending rigidity value also in the width direction of the absorbent article. This is from the viewpoint of the softness of the absorbent article.

In this specification, the bending stiffness value in the longitudinal direction of the absorbent article by the KES method is measured as follows.
(1) A large pure bending tester KES-FB2-L manufactured by Kato Tech Co., Ltd. is prepared in a constant temperature and humidity chamber at 20 ° C. and 60% RH.
(2) The sample to be measured is left in the constant temperature and humidity chamber for 24 hours.
(3) The sample to be measured is cut at two places at 5 cm in the longitudinal direction around the place to be measured in the longitudinal direction (for example, the center in the longitudinal direction) to obtain a sample piece having a length in the longitudinal direction of 10 cm. . When the sample to be measured has a flap, the flap portion is cut and excluded.

(4) The sample piece can be measured on the pair of jigs of the testing machine so that the position to be measured is placed between the pair of jigs, and the bending stiffness in the longitudinal direction of the sample to be measured can be measured. Set as follows. The sample piece is set on a pair of jigs such that the sample piece is bent in the direction of the liquid-impermeable layer of the sample to be measured (the curvature becomes positive).
(5) The sample piece is subjected to a bending test to a curvature of 0 to +0.5 cm ^−1, and the relationship between the curvature and the bending moment (gf · cm / cm) is plotted.
(6) The bending moment value at the time of curvature +0.1 cm ⁻¹ is divided by the curvature to calculate the bending stiffness value of the sample piece, and converted to SI units (N · m ² / m).
(7) Repeat the measurement 5 times in total and adopt the average value.

  In the absorbent article of the present disclosure, as shown in the first embodiment, the absorbent body includes cellulosic water absorbent fibers and thermoplastic resin fibers having a fiber length longer than the cellulosic water absorbent fibers, And at least one part of the thermoplastic resin fiber of an absorber is joined to the liquid-permeable layer. By doing so, the bonding force between the absorbent body and the liquid permeable layer is increased, they are integrated, and the absorbent article is easily bent along the concave portion of the liquid permeable layer, which is an easily bent portion. Moreover, an absorbent article becomes difficult to sway. The reason why the absorbent article is easily bent along the recesses of the liquid-permeable layer will be described later.

As the bonding, for example, at least a part of the thermoplastic resin fiber of the absorber by fusion, bonding with the liquid permeable layer, at least a part of the thermoplastic resin fiber of the absorber by the adhesive portion, Examples include bonding with a permeable layer.
The fusion will be described later. The adhesive part may be formed of an adhesive known in the art, for example, a hot melt adhesive.

In the absorbent body of the absorbent article of the present disclosure, as shown in the first embodiment, at least a part of the thermoplastic resin fiber is exposed to one surface of the absorbent body, and the other of the absorbent body It is preferable to have a second portion exposed on the surface of the substrate and a connecting portion that connects the first portion and the second portion (hereinafter may be referred to as “specific thickness direction orientation”). Thereby, the thermoplastic resin fiber functions as a skeleton for holding other components of the absorbent body, for example, the cellulosic water-absorbing fiber, and improves the strength of the absorbent body while maintaining the softness of the absorbent body. be able to. As a result, when force such as body pressure is applied, delamination within the absorber is less likely to occur, and the absorber does not contain the thermoplastic resin fiber, for example, an absorption containing only pulp fibers. Although it becomes harder than a body, it has the softness equivalent to the absorber containing only a pulp fiber.
Examples of the one surface and the other surface include a skin-side surface and a clothing-side surface of the absorbent body, respectively.

  Moreover, when the thermoplastic resin fiber has a specific thickness direction orientation, the bonding between the absorber and the liquid permeable layer is excellent in both the bonding by fusion and the bonding by the adhesive portion. For example, when the absorbent body contains only pulp, only the surface of the absorbent body and the liquid-permeable layer are joined in the joining by the adhesive portion, and peeling within the layer tends to occur inside the absorbent body. Become. As a result, the absorbent article is less likely to bend along the concave portion of the liquid permeable layer, which is a part that is easily bent, and irregular folds are likely to be formed in the liquid permeable layer of the absorbent article. Moreover, an absorbent article becomes easy to sway.

  Examples of the thermoplastic resin fibers include those containing a single component, for example, single fibers, or those containing a plurality of components, for example, composite fibers. The above components include polyethylene, polypropylene, polybutylene, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, ethylene-acrylic acid copolymer, polyolefin such as ionomer resin; polyethylene terephthalate (PET), poly Examples include butylene terephthalate (PBT), polytrimethylene terephthalate (PTT), polyester such as polylactic acid; polyamide such as nylon.

  Examples of the composite fibers include, for example, composite fibers such as core-sheath fibers, side-by-side fibers, and island / sea fibers; hollow fibers; irregular fibers such as flat, Y-type, and C-types; latent crimps or manifestations Three-dimensional crimped fibers of crimps; split fibers that are split by physical load such as water flow, heat, embossing, etc., and core-sheath fibers that are obtained industrially inexpensively and have high safety, PET / PE, PP / PE (core / sheath) and the like are preferable.

  As the cellulose-based water-absorbing fiber, non-wood such as pulp fiber, for example, wood pulp fiber, bagasse fiber, kenaf fiber, bamboo fiber, hemp fiber, cotton fiber (for example, cotton linter) obtained from softwood or hardwood Examples thereof include pulp fibers; regenerated cellulose fibers such as rayon fibers; semisynthetic fibers such as acetate fibers. The pulp fiber is preferably kraft pulp fiber that is industrially inexpensive and highly safe.

  The average fiber length of the cellulosic water-absorbing fiber is not particularly limited. Moreover, when the said cellulose water-absorbing fiber is a regenerated cellulose fiber, a semisynthetic fiber, etc., it can have average fiber lengths, such as about 3 to about 70 mm, about 5 to about 50 mm, about 10 to about 40 mm. Depending on the fiber length, the regenerated cellulose fiber, semi-synthetic fiber and the like have the same function as the thermoplastic resin fiber during drying, and can impart difficulty to the absorbent body.

  The absorber preferably comprises about 5 to about 50 parts by weight and about 50 to about 95 parts by weight of thermoplastic resin fibers and cellulosic water-absorbing fibers, respectively, based on a total of 100 parts by weight thereof, and More preferably, it is contained in a ratio of about 10 to about 40 parts by weight and about 60 to about 90 parts by weight. When the ratio of the thermoplastic resin fibers is less than about 5 parts by mass, the strength of the absorber becomes insufficient, the absorbers tend to bend, and when the ratio of the thermoplastic resin fibers exceeds 50 parts by mass There is a tendency that the liquid absorbency of the absorber is insufficient.

  The thermoplastic fiber preferably has an average fiber length of about 6 to about 70 mm, more preferably about 10 to about 50 mm, and even more preferably about 15 to about 40 mm. When the average fiber length is less than about 6 mm, the thermoplastic resin fiber tends to have difficulty in having a specific thickness direction orientation, and the thermoplastic resin fiber is another thermoplastic resin fiber and / or cellulose. It tends to be difficult to entangle with the water-absorbing fiber.

Further, if the average fiber length exceeds about 70 mm, the openability of the thermoplastic resin fiber is remarkably reduced, and the absorbent body includes thermoplastic resin fibers that are not opened, and the uniformity of the absorbent body is increased. There is a tendency to decrease.
In addition, the said average fiber length is especially preferable when an absorber is mixed with a cellulosic water absorbing fiber, for example, a pulp fiber, by an airlaid system.

  In the absorbent body of the absorbent article of the present disclosure, the thermoplastic fiber preferably has a fineness of about 0.5 to about 10 dtex, and more preferably about 1.5 to about 5 dtex. When the fineness is less than about 0.5 dtex, the openability of the thermoplastic resin fibers may be reduced, and when the fineness exceeds 10 dtex, the number of thermoplastic resin fibers decreases, and other thermoplastics There is a tendency that the number of points entangled with resin fibers and / or cellulosic water-absorbing fibers is reduced.

In the absorbent article of the present disclosure, the tensile strength in the thickness direction of the absorbent body is preferably 100 Pa or more, more preferably 150 Pa or more, still more preferably 200 Pa or more, and even more preferably 250 Pa or more. When the tensile strength is less than 100 Pa, the amount of the thermoplastic resin fiber having a specific orientation in the thickness direction in the absorber, the amount of the embossed portion of the absorber, etc. are insufficient, and the strength of the absorber is weak, There exists a tendency for an absorber to become easy to twist. In addition, the bonding between the thermoplastic resin fibers of the absorbent body and the liquid permeable layer becomes insufficient, and the absorbent article is less likely to bend along the recesses of the liquid permeable layer, which is an easily bent part. Irregular folds are likely to be formed in the liquid-permeable layer.
Moreover, in the absorbent article of this indication, although the upper limit of the tensile strength of the thickness direction of an absorber is not specifically limited, From a soft viewpoint, it is 3,000 Pa or less.

In the present disclosure, the tensile strength is measured as follows using the apparatus shown in FIG.
(1) A pair of acrylic jigs 51 (diameter 68 mm, mass of each jig: 200 g, height of the grip portion 51 a: 50 mm) is prepared.
(2) A sample 52 having a diameter of 68 mm is prepared from the absorber.
(3) Two sheets of double-sided tape 53 (manufactured by 3M, adhesive transfer tape 950) cut out to a diameter of 68 mm are prepared.

(4) As shown in FIG. 6, the sample 52 is fixed to a pair of jigs 51 using two double-sided tapes 53.
(5) A pair of jigs 51 having the sample 52 is placed on the holding base 55, and a weight 54 (10.5 kg) is placed thereon, and left for 3 minutes.
(6) A pair of jigs 51 is set to a tensile tester (Shimadzu Corporation, AG-1kNI) with a gripping interval of 70 mm.

(7) The sample 52 is subjected to a tensile test at a speed of 100 mm / min until the sample 52 peels in the layer, and the maximum tensile force (N) at that time is recorded.
(8) The measurement is repeated 5 times in total, the average value of the maximum tensile force (N) is obtained, and the following formula:
Tensile strength (Pa) = Average value of maximum tensile force (N) /0.003632 (m ² )
According to the above, the tensile strength (Pa) is calculated.
The measurement is carried out at 20 ° C.

  In the absorbent body, the thermoplastic resin fiber is preferably about 2 times or more, more preferably about 3 times or more, still more preferably about 4 times or more, still more preferably about 5 times or more the thickness of the absorbent body. And even more preferably has an average fiber length of about 7 times or more. If the magnification is less than about 2 times, it tends to be difficult for the thermoplastic resin fibers to have a specific thickness direction orientation.

  In the absorbent body, the thermoplastic resin fibers have an average fiber length that is preferably about 30 times or less, more preferably about 20 times or less, and even more preferably about 15 times or less the thickness of the absorbent body. . If the magnification is more than about 30 times, the opening of the thermoplastic resin fibers becomes insufficient, and the thermoplastic resin fibers tend to have a specific thickness direction orientation.

  In the absorbent article of the present disclosure, as shown in the first embodiment, the liquid-permeable layer (first liquid-permeable layer) includes a plurality of concave portions on the skin contact surface. It is preferable that the said recessed part is arrange | positioned continuously or intermittently in a predetermined direction in the skin contact surface of a liquid-permeable layer. When the bonding force between the absorbent body and the liquid permeable layer is sufficiently high, the absorbent article is easily bent when the force is applied to the absorbent article, along the recess of the liquid permeable layer. It becomes easy to bend in a predetermined direction, and it becomes difficult for the absorbent article to remain in the absorbent article. Moreover, since it becomes difficult for the absorbent article to form irregular folds extending in a direction other than a predetermined direction, for example, an unintended direction, the wearer is less likely to feel uneasy.

The concave portion includes not only a bottom portion but also a portion having no bottom portion, that is, a through hole and extending in a predetermined direction, for example, a groove portion having a bottom portion, a slit portion having no bottom portion, and the like.
The recesses preferably have a pitch of 8 mm or less, and more preferably 5 mm or less. When the pitch exceeds 8 mm, the absorbent article is difficult to bend along the concave portion of the liquid permeable layer, and irregular wrinkles are easily formed in the liquid permeable layer of the absorbent article.

  In the liquid permeable layer (first liquid permeable layer), it is preferable that the basis weight of the concave portion is lower than the basis weight of the portion other than the concave portion, for example, the convex portion. By doing so, compared to the case where the basis weight of the recess is equal to that of the portion other than the recess, the recess of the liquid-permeable layer is relatively easily bent, and the absorbent article is easily bent along the recess. , It becomes difficult for the absorbent article to remain.

  In the liquid permeable layer (first liquid permeable layer), the basis weight of the concave portion may be equal to the basis weight of a portion other than the concave portion, for example, the convex portion. This is because if the height of the recess is lower than the portion other than the recess, the liquid-permeable layer and the absorbent article are easily bent along the recess.

  The liquid permeable layer (first liquid permeable layer) is formed by injecting gas onto a web containing thermoplastic resin fibers to form a recess in the web, and then heat-treating the web having the recess to heat the web. It is preferable that the nonwoven fabric is produced by heat-sealing the intersecting portions of the plastic resin fibers. The liquid-permeable layer, and thus the absorbent article, tends to bend along the concave part, for example, the basis weight of the recess is smaller than the basis weight of the region other than the recess, and a fold remains in the liquid-permeable layer of the absorbent article. Hateful. Further, irregular folds are hardly formed in the liquid-permeable layer of the absorbent article.

  In the absorbent article of the present disclosure, the liquid-permeable layer has a bending rigidity value per unit length in the width direction of the absorbent article that is lower than the bending rigidity value per unit length in the longitudinal direction of the absorbent article. It is preferable to have. The liquid permeable layer is easily bent in the width direction, and irregular folds are hardly formed in the liquid permeable layer.

  The bending rigidity value per unit length is a direction corresponding to the longitudinal direction and the width direction of the absorbent article by cutting a sample piece of 10 × 10 cm (length in the longitudinal direction × length in the width direction) from the liquid-permeable layer. The bending stiffness value is measured according to the measuring method of “the bending stiffness value in the longitudinal direction by the KES method” except that the bending stiffness value is divided by the width of the sample piece. In addition, when it is difficult to cut the above-described sample piece from the liquid-permeable layer, the above value is calculated by cutting the sample piece with a possible size and dividing by the length.

  As shown in the first embodiment, the absorbent article of the present disclosure may be referred to as an embossed portion formed by embossing a liquid-permeable layer and an absorbent body (hereinafter referred to as “first embossed portion”). Preferably). Since the absorbent body and the liquid permeable layer are firmly bonded to each other, it becomes difficult to delaminate between them, and the absorbent article is easy to bend along the recess of the liquid permeable layer, which is a part that is easy to bend. Therefore, irregular folds are hardly formed in the liquid-permeable layer of the absorbent article.

  Moreover, in the 1st embossed part, it is preferable that the thermoplastic resin fiber of an absorber is joined by fuse | melting with a liquid-permeable layer from a viewpoint of the intensity | strength of joining. From the viewpoint of the above fusion, it is preferable that the composition of the thermoplastic resin fibers of the absorber and the composition of the first liquid-permeable layer are the same and they are fused.

  In the absorbent article according to the present disclosure, in the embodiment in which the liquid permeable layer includes the first liquid permeable layer on the skin surface side and the second liquid permeable layer on the clothing side, the absorbent article is the second liquid. It is preferable to provide an embossed portion (hereinafter, also referred to as “second embossed portion”) formed by embossing the permeable layer and the absorber. Since the absorbent body and the second liquid permeable layer are firmly bonded to each other by the embossed portion, delamination between them becomes difficult, and the absorbent body (absorbent article) is a part that is easily bent. It becomes easy to bend along the recessed part of a permeable layer, and an irregular crease is hard to be formed in the 1st liquid permeable layer of an absorbent article.

Moreover, in the 2nd embossed part, it is preferable that the thermoplastic resin fiber of an absorber is joined by fuse | melting with a 2nd liquid-permeable layer from a viewpoint of the intensity | strength of joining. From the viewpoint of the above fusion, it is preferable that the composition of the thermoplastic resin fiber of the absorbent body and the composition of the second liquid-permeable layer are the same and they are fused.
Note that the second embossed portion does not include the first liquid-permeable layer.

The following effects (i) to (iii) are obtained by the first embossed portion and / or the second embossed portion.
(I) Since the plurality of thermoplastic resin fibers contained in the absorbent body are connected via the embossed portion (the first embossed portion and / or the second embossed portion), the absorbent body has a substantially longer average fiber length. The thermoplastic resin fiber has a higher function than the case without an embossed part as a skeleton for holding other fibers, for example, cellulosic water-absorbing fibers. The strength of the absorber is improved.

(Ii) When the liquid permeable layer and the absorbent body are joined together by the first embossed portion, delamination between the liquid permeable layer and the absorbent body becomes difficult, and intralayer delamination occurs inside the absorbent body. It becomes difficult to do. As a result, the absorbent article is easy to bend along the concave portion of the liquid permeable layer, which is an easily foldable part, and irregular folds are not easily formed in the liquid permeable layer of the absorbent article. It becomes difficult to drool.
(Iii) When the second liquid-permeable layer and the absorbent body are joined by the second embossed portion, delamination between the second liquid-permeable layer and the absorbent body becomes difficult, and the interior of the absorbent body It becomes difficult to peel in the layer. As a result, the absorbent article is easy to bend along the concave portion of the first liquid permeable layer, which is a part that is easily bent, and the first liquid permeable layer of the absorbent article is less likely to be irregularly folded and absorbed. It becomes difficult for the sexual article to sway.

In the embossed part (the first embossed part and / or the second embossed part), the thermoplastic resin fiber of the absorbent body is fused with other fibers of the absorbent body, for example, the cellulose-based water absorbent fiber and the thermoplastic resin fiber. It is preferable. This is from the viewpoint of the above effect.
When the liquid permeable layer includes thermoplastic resin fibers, the thermoplastic resin fibers of the liquid permeable layer are fibers constituting the absorber, for example, thermoplastic resin fibers or cellulosic water absorbent fibers, particularly thermoplastic resins. It is preferably fused with the fiber. This is from the viewpoint of the above effect. From this point of view, it is preferable that the composition of the thermoplastic resin fiber of the absorber is the same as the composition of the thermoplastic resin fiber of the liquid-permeable layer.

  In the absorbent body, the thermoplastic resin fibers are fused with the cellulosic water absorbent fibers and / or other thermoplastic resin fibers in a region other than the embossed portion (the first embossed portion and / or the second embossed portion). Preferably not. When regions other than the embossed portion are fused, the absorber tends to become hard.

In the absorbent body, the area ratio of the embossed part (first embossed part and / or second embossed part) to the area of the absorbent body is preferably 1 to 20%, more preferably 2 to 15%, and still more preferably. 3 to 10%. When the area ratio is less than 1%, the action of the second embossed portion tends not to appear, and when the area ratio is more than 10%, the absorbent body is difficult to kink, but the wearer is hard on the absorbent body. Tend to feel.
The “area of the absorber” and “area of the embossed part” mean the area when the absorber is observed in the thickness direction.

The shape of the embossed part (the first embossed part and / or the second embossed part), in particular, the second embossed part is not particularly limited, and examples of the shape of the embossed part include a dotted embossed part and a linear embossed part. It is done. Examples of the dot-like embossed portion include a circle, an ellipse, a rectangle, a triangle, a star, and a heart shape.
The arrangement of the embossed portions is not particularly limited, and examples thereof include a zigzag pattern such as a square zigzag pattern and a 60 ° zigzag pattern.

  The distance between adjacent embossed parts (first embossed part and / or second embossed part), particularly the second embossed part, is preferably not more than 2.0 times the average fiber length of the thermoplastic resin fibers contained in the absorbent body. It is preferably 1.0 times or less, more preferably 0.7 times or less, and even more preferably 0.5 times or less. When the interval is longer than 2.0 times the average fiber length of the thermoplastic resin fibers, the thermoplastic resin fibers fixed to different second embossed portions are not entangled with each other, and the strength of the absorber is hardly improved. In addition, when the interval is 0.5 times or less of the average fiber length of the thermoplastic resin fibers, one thermoplastic resin fiber may be fixed to the plurality of second embossed portions. Strength is easy to improve.

The individual embossed parts (first embossed part and / or second embossed part), in particular the individual second embossed parts are preferably 0.1 to 20.0 mm ² , more preferably 1.0 to 15.0 mm ² , More preferably, it has an area of 2.0 to 10.0 mm ² . When the area is less than 0.1 mm ² , the protrusion of the embossing roll when forming the embossed portion has an acute angle, the absorber and / or the liquid permeable layer may be broken, and the area is 20.0 mm ² . When it exceeds, there exists a tendency for an absorber to become hard.

  In the embodiment in which the absorbent article of the present disclosure includes the second liquid permeable layer, the second liquid permeable layer is not particularly limited, and those used for the absorbent article in the present technical field are employed without limitation. Can do. The second liquid permeable layer preferably contains thermoplastic resin fibers. This is because it can be fused with the thermoplastic resin fiber of the absorber.

  Examples of the second liquid-permeable layer include fabrics such as non-woven fabrics and woven fabrics, synthetic resin films formed with liquid permeable holes, and the non-woven fabrics include, for example, air-through non-woven fabrics, spunbonded non-woven fabrics, Examples of the air-laid nonwoven fabric include air-laid pulp. Examples of the thermoplastic resin fiber that can be contained in the second liquid-permeable layer include those equivalent to the thermoplastic resin fiber contained in the absorber.

  In the absorbent article of the present disclosure, the preferred thickness of the absorbent body varies depending on the use or the like of the absorbent article, but is generally about 0.1 to about 15 mm, preferably about 1 to about 10 mm, and more preferably. Has a thickness of about 2 to about 5 mm.

In the present specification, the thickness (mm) of the absorber is measured as follows.
FS-60DS [measurement surface 44 mm (diameter), measurement pressure 3 g / cm ² ] manufactured by Daiei Kagaku Seisakusho Co., Ltd. is prepared and absorbed under standard conditions (temperature 23 ± 2 ° C., relative humidity 50 ± 5%). Pressurize five different parts of the body, measure the thickness of each part 10 seconds after pressurization, and take the average of the five measured values as the thickness of the absorber.

In the absorbent article of the present disclosure, the absorber is generally from about 20 to about 1000 g / m ^2, preferably from about 50 to about 800 g / m ^2, and more preferably from about 100 to about 500 g / m ² basis Have quantity. This is from the viewpoint of the strength and absorbability of the absorber.

In the absorbent article of the present disclosure, the absorber preferably further includes a superabsorbent material. The absorbent comprises the superabsorbent material, preferably from about 5 to about 80% by weight, more preferably from about 10 to about 60% by weight and even more preferably from about 20 to about 40% by weight of the total weight of the absorber. Including in the range of mass%.
Examples of the superabsorbent material include starch, cellulose, and synthetic polymer superabsorbent materials.

[Production method]
FIG. 7 is a diagram for explaining an absorbent body manufacturing apparatus for absorbent articles according to one embodiment of the present disclosure, and an absorbent body manufacturing method using the manufacturing apparatus.
The manufacturing apparatus 101 shown in FIG. 7 includes a first fiber group that includes a first fiber group including thermoplastic resin fibers, and opens a first web 111 that is continuous in the length direction and has a predetermined width and thickness. 1 opening device 103 and a second opening device 104 for opening a second web 112 made of a second group of fibers including cellulosic water-absorbing fibers.

  The manufacturing apparatus 101 flows the first absorbent material 113 opened by the first spreader 103 and the second absorbent material 114 opened by the second spreader 104 into the inside. The transfer pipe 105 is provided. In the transport pipe 105, the first absorbent material 113 and the second absorbent material 114 are transported from upstream to downstream by air. In addition, the manufacturing apparatus 101 includes a forming apparatus 106 disposed at the most downstream position of the transport pipe 105. In the molding apparatus 106, the first absorbent material 113 and the second absorbent material 114 conveyed from the upstream side of the conveyance pipe 105 are laminated to form an absorbent body.

  The first spreader 103 opens the first web 111 formed by a general web spreader (not shown), and forms the first absorbent material 113. The first fiber opening device 103 quantitatively opens the first web 111, and quantitatively flows a predetermined amount of the first absorbent material 113 into the transport pipe 105.

The first opening device 103 is arranged on a rotating shaft 131 extending in the horizontal direction, a substantially cylindrical opening cylinder 133 provided to be rotatable around the axis of the rotating shaft 131, and an outer peripheral surface of the opening cylinder 133. The rotary blade portion 132 includes a plurality of opening blades 134 that are provided and rotate together with the opening cylinder 133.
In addition, the code | symbol 136-140 in FIG. 7 is a walker roll provided along the outer peripheral surface of the rotary blade part 132, and opening the 1st web 111 with the rotary blade part 132. FIG.

  Moreover, the 1st fiber-spreading apparatus 103 is provided with the casing member 135 provided so that the rotary blade part 132 and the walker rolls 136-140 might be covered. The casing member 135 has a loading port 135 a for inserting the first web 111 on the left side of the rotary blade part 132, and an airtight connection part with the transport pipe 105 on the right side of the rotary blade part 132.

  The second fiber opening device 104 opens the second web 112 to form the second absorbent material 114. The second fiber opening device 104 quantitatively opens the second web 112, and causes a predetermined amount of the second absorbent material 114 to flow into the transport pipe 5 quantitatively.

  The second fiber opening device 104 includes a rotation shaft 141 that extends horizontally in the same direction as the rotation shaft 131 of the first fiber opening device 103, and a substantially cylindrical opening that is rotatably provided around the axis of the rotation shaft 141. And a rotating blade part 142 provided with a plurality of opening blades 144 disposed on the outer peripheral surface of the opening cylinder 143 and rotating together with the opening cylinder 143.

  The second fiber opening device 104 is provided with a casing member 145 that covers the outer peripheral surface of the rotary blade portion 142 and is close enough not to contact the blade 144. Then, when the second web 112 is inserted into the space between the casing member 145 and the rotary blade portion 142 through the loading port 145a, the blade 144 of the rotating rotary blade portion 142 is moved to the second web. While pulling 12 in the direction of the conveying pipe 105, the fibers of the second web 112 are scraped off and opened.

  Further, the casing member 145 has the outer peripheral surface of the rotary blade portion 142 and further the width direction (axis line) of the rotary blade portion 142 up to a position where the second opening device 104 is connected to the transport pipe 105 except for the inlet 145a. Both ends of the direction) are airtightly covered, and the inside of the casing member 145 and the inside of the transport pipe 105 are kept in airtight communication.

  The transport pipe 105 has both the first absorbent material 113 introduced from the first spreader 103 and the second absorbent material 114 introduced from the second spreader 104. Is conveyed toward the molding apparatus 106, and in this embodiment, an inner peripheral surface having a substantially rectangular cross section is provided.

  In addition, the transport pipe 105 is provided with a first throttle 151 that is smaller than the flow area of the nearest upstream portion at a portion where the second spreader 104 is connected, and the first throttle The first absorber material 113 and the second absorber material 114 that are connected to the first restrictor 151 and have a larger flow area than the first restrictor 151 are provided downstream of the part 151. A first mixing space 152 is provided for mixing using a pressure difference from the first throttle 151. In the first throttle unit 151, the flow area is reduced by disposing the rotary blade 142 of the second fiber opening device 104 so as to enter the transport pipe 105.

  Furthermore, the transport pipe 105 is arranged downstream of the first mixing space 152, a second throttle part 153 smaller than the upstream flow area, and downstream of the second throttle part 153. A second mixing space part 154 having a larger flow area than the second throttle part 153. The second mixing space 154 mixes the first absorber material 113 and the second absorber material 114 using a pressure difference with the second throttle portion 153.

  The transport pipe 105 passes through the first throttle part 151, the first mixing space part 152, the second throttle part 153, and the second mixing space part 154 and passes through the first absorber material 113 and the second absorber material. While mixing 114, the first absorber material 113 and the second absorber material 114 are supplied to the molding apparatus 106.

  The molding device 106 sucks the first absorbent material 113 and the second absorbent material 114 by sucking the air in the transport pipe 105 on the outer peripheral surface while rotating around the axis of the rotary shaft 161, A cylindrical suction drum 162 to be stacked is provided. Further, the molding apparatus 106 includes a cover member 163 that covers the upper portion of the outer peripheral surface of the suction drum 162 and guides the first absorbent material 113 and the second absorbent material 114 to the outer peripheral surface of the suction drum 162. ing.

  In addition, a supply device 163 a for supplying the superabsorbent material 116 is provided inside the cover member 163. Further, the suction drum 162 has a central portion in the width direction on the outer peripheral surface of the suction drum 162 formed in a groove shape extending in the circumferential direction of the outer peripheral surface. Then, by sucking air from the inside of the suction drum 162, the first absorbent material 113 and the second absorbent material 114 are laminated on the central portion in the width direction of the outer peripheral surface. Thereby, the absorber continuum 107 continuously formed in the length direction is formed.

  Since the transport pipe 105 takes in outside air only through the first fiber opening device 103, when the suction drum 162 sucks air in the transport pipe 105, the transport tube 105 takes in air only through the first fiber opening device 103, The first absorbent material 113 and the second absorbent material 114 are air conveyed from upstream to downstream of the conveyance pipe 105. Thereby, the 1st absorber material 113 and the 2nd absorber material 114 are conveyed quantitatively.

  The absorber continuum 107 formed on the outer peripheral surface of the suction drum 162 moves downstream of the suction drum 162 as the suction drum 162 rotates, and the upper surface of the carrier sheet 164 that forms a liquid-permeable layer. In addition, the continuous laminated body 107 of the absorber continuous body 107 and the carrier sheet 164 is formed by being placed through an adhesive.

  Next, an embossed portion is formed on the continuous laminate 107 by an embossing device 171 including a pair of embosses, and then the continuous laminate 107 is cut by a cutting device 181, whereby an absorbent body and a carrier sheet laminate 191. Is formed.

  In order to fuse the thermoplastic resin fibers of the absorber with the liquid-permeable layer, in the embossing apparatus, the temperature of the embossing roll is preferably set to a temperature equal to or higher than the temperature at which a part of the thermoplastic resin fibers is melted. For example, when the thermoplastic resin fiber is a sheath-core type composite fiber, the temperature is preferably equal to or higher than a temperature at which a part of the sheath component starts to melt.

  The temperature of the embossing roll is usually about 80 to about 160 ° C., preferably about 120 to about 160 ° C., and the pressure is usually about 10 to about 3000 N / mm, preferably about 50 to about 500 N / mm. The time is usually about 0.0001 to about 5 seconds, preferably about 0.005 to about 2 seconds.

  The absorbent article of this indication can be manufactured by a publicly known method in the art using the above-mentioned layered product 191.

  EXAMPLES Hereinafter, although this invention is demonstrated further in detail based on an Example, the scope of the present invention is not limited to an Example.

[Production Example 1]
(1) Manufacture of laminated body of absorbent body and second liquid permeable layer By the production apparatus shown in FIG. 7, an absorbent body continuum (pulp and thermoplastic resin fibers in a mass ratio of 85:15 is formed. Including, a continuous laminate of basis weight: 250 g / m ² ) and a carrier sheet (commercial air-through nonwoven fabric, basis weight: 30 g / m ² ) forming the second liquid-permeable layer. The thermoplastic resin fiber was a core-sheath fiber having a core of polyethylene terephthalate and a sheath of polyethylene, an average fiber length of 30 mm, and a fineness of 2.2 dtex.

  Next, the continuous laminated body was passed through a pair of embossing rolls, and a second embossed portion was formed on the continuous laminated body. The embossing roll is a pin embossing roll in which pin embossing portions having a diameter of 1 mm are arranged in a staggered pattern with respect to the MD direction, and the center-to-center distance between the pin embossing portions is 10 mm × 10 mm (MD direction × CD direction) And a plain roll. Next, the continuous laminate was cut into a size of 50 mm length × 25 mm width, and the absorbent body and the second liquid permeable layer No. 1 was obtained.

(2) Production of first liquid permeable layer (i) Production of web Composite fiber (average fineness: 1.8 dtex, average fiber length: 45 mm) having polyethylene terephthalate as a core component and polyethylene as a sheath component, and polyethylene terephthalate From a mixture (mass ratio 1: 1) with a composite fiber (average fineness: 2.4 dtex, average fiber length: 45 mm) having polyethylene as a core component and polyethylene as a sheath component. 1 (basis weight: 25 g / m ² ) was formed.

(Ii) Fabrication of nonwoven web No. 1 to 1st liquid-permeable layer No. 1 having a ridge groove structure including a ridge portion (convex portion) and a groove portion (concave portion) according to the method described in JP-A-2008-23311. 1 was obtained.
Various settings in the nonwoven fabric manufacturing apparatus used are as follows.
Diameter of injection port 332: 1.0 mm (perfect circle)
The pitch of the injection holes 322: 3.0 mm
Injection gas temperature: 310 ° C
Air flow rate per jet port: 5 L / min Web conveyance speed: speed 100 m / min Breathable support member 310 (net-like support member): 70 mesh Heat treatment by heater unit 340: Heat treatment temperature 140 ° C., passing air speed Treatment at 1.2 m / second for 6 seconds First liquid permeable layer No. 1 In 1, the basis weight of the groove portion was lower than the basis weight of the heel portion.

A polyethylene sheet (basis weight: 23 g / m ² ) was cut into a product size, and the liquid-impermeable layer No. 1 was obtained.
Next, the liquid-impermeable layer No. 1 is coated with a hot melt adhesive in a spiral shape with a basis weight of 5 g / m ² , and the absorbent body and the second liquid-permeable layer No. 1 are coated thereon. 1 and the second liquid permeable layer No. 1 was laminated. 1 was coated with a hot-melt adhesive in a spiral shape with a basis weight of 5 g / m ² . 1 is laminated so that the groove structure extends in the longitudinal direction of the absorbent article. 1 was obtained.

[Production Example 2]
Commercially available absorbent articles No. 2 and no. 3 was prepared.
Absorbent article no. No. 2 includes a top sheet, an absorbent body, and a back sheet. The absorbent body includes an absorbent core containing pulp fibers and a superabsorbent polymer and a tissue covering the absorbent core, and an embossed portion is formed on the entire surface. Moreover, the top sheet was an air-through nonwoven fabric having a ridge groove structure on the skin contact surface, and the top sheet and the absorbent body were joined by a hot melt adhesive. The ridge groove structure has the absorbent article no. It was the same as that of No. 1 groove structure.

  Absorbent article no. 3 includes a top sheet, an absorbent body and a back sheet, and the absorbent body was formed from airlaid pulp having a laminated structure. The top sheet was an air-through nonwoven fabric with a flat skin contact surface, and the top sheet and the absorbent body were bonded with a hot melt adhesive.

[Example 1]
[Bending stiffness value]
Absorbent article no. 1-No. 3, the bending stiffness value in the longitudinal direction was measured. The results are shown in Table 1.

To a plurality of volunteer subjects, an absorbent article No. 1 to No. 3 was worn, and the wear feeling, eclectic resistance, and absorbency were judged according to the following criteria. The results are shown in Table 1.
[A feeling of wearing]
○: The absorbent article was soft, followed the movement of the body, and excellent in wearing feeling.
(Triangle | delta): Depending on operation | movement, the hardness of the absorbent article was felt and there existed a case where it was inferior to a feeling of wear.
X: The absorbent article was hard, did not follow the movement of the body, and was inferior in wearing feeling.

[Eclectic resistance]
○: After wearing for a long time, the eclectic of the absorbent article did not matter.
X: After wearing for a long time, I was worried about the compromise of the absorbent article.
[Absorptive]
○: The stickiness of the surface was not noticed even after wearing for a long time.
X: After wearing for a long time, I was worried about the stickiness of the surface.

  Absorbent article no. No. 1 was excellent in wearing feeling, eclectic resistance and absorbability. Although there was a compromise, it was generally along the groove structure. Absorbent article no. 2 was hard and inferior in wearing feeling. There were few eclectic and generally along the groove structure. In addition, during wearing, a gap is formed between the top sheet and the absorbent body, which is considered to be inferior in absorbability. Absorbent article no. The number of 3 was not a compromise, but the direction was random.

DESCRIPTION OF SYMBOLS 1 Absorbent article 2 1st liquid permeable layer 3 Absorber 4 Skin contact surface 5 Recessed part 6 1st embossed part 7 Side sheet 8 Seal part 9 2nd liquid permeable layer 10 2nd embossed part 21 Cellulosic water absorbing fiber 22 Thermoplastic resin fiber 23 One surface 24 Other surface 31, 32 Adhesion portion 33 Liquid impermeable layer 34 Fixing portion 51 Jig 52 Sample 53 Double-sided tape 54 Weight 55 Holding stand

Claims (9)

An absorbent article having a longitudinal direction and a width direction, comprising a liquid-permeable layer having a skin contact surface, a liquid-impermeable layer, and an absorbent body between the liquid-permeable layer and the liquid-impermeable layer. Because
The liquid permeable layer has a plurality of recesses on the skin contact surface,
The absorbent comprises a cellulosic water absorbent fiber and a thermoplastic resin fiber having a longer fiber length than the cellulosic water absorbent fiber,
At least a part of the thermoplastic resin fiber of the absorbent body is bonded to the liquid-permeable layer, and the absorbent article is 3 to 15 mN · m ² / m in length by the KES method. Having a bending stiffness value in the direction,
The absorbent article.   The absorbent article according to claim 1, wherein the plurality of recesses are continuously or intermittently arranged in a predetermined direction on the skin contact surface.   The absorbent article according to claim 1 or 2, wherein in the liquid-permeable layer, the basis weight of the recess is lower than the basis weight of a portion other than the recess.   After the liquid permeable layer injects gas to the web containing thermoplastic resin fibers to form a plurality of recesses in the web, the web having the recesses is heat-treated to make the thermoplastic resin fibers in the web The absorptive article according to any one of claims 1 to 3 which is a nonwoven fabric manufactured by heat-sealing a crossing part.   The liquid-permeable layer has a bending rigidity value per unit length in the width direction that is lower than a bending rigidity value per unit length in the longitudinal direction. Absorbent article as described in 1.   The absorbent article includes an embossed portion formed by embossing the liquid permeable layer and the absorber, and in the embossed portion, the thermoplastic resin fiber of the absorber is the liquid permeable layer. The absorbent article as described in any one of Claims 1-5 currently melt | fused.   The liquid permeable layer includes a first liquid permeable layer on the skin surface side and a second liquid permeable layer on the clothing side, and the absorbent article includes a second liquid permeable layer, the absorber, and the absorbent body. The absorbent article as described in any one of Claims 1-6 provided with the embossing part formed by embossing.   At least a part of the thermoplastic resin fiber has a first part exposed on one surface of the absorber, a second part exposed on the other surface of the absorber, a first part, and a second part. The absorbent article as described in any one of Claims 1-7 which has a connection part which connects these parts.   The absorption according to any one of claims 1 to 8, wherein the thermoplastic resin fibers have an average fiber length of 6 to 70 mm, and the absorber has a tensile strength in the thickness direction of 100 Pa or more. Sex goods.

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