KR20210098942A - absorbent article - Google Patents

Abstract

An object of the present invention is to provide an absorbent article comprising a topsheet excellent in feel that is unlikely to cause unpleasant irritation to the wearer's skin. In the absorbent article of the present invention, the topsheet 2 includes a water-retaining fiber F ₁ , and includes a first fibrous layer 2a forming the skin-side surface of the topsheet 2; , comprising thermoplastic resin fibers (F ₂ ) and water-retaining fibers (F ₁ ), and forming a non-skin surface of the topsheet 2 adjacent to the non-skin side of the first fibrous layer 2a and a second fiber layer (2b) to the first fiber layer (2a) the rate of water retention fibers (F ₁₎ of the fibers forming said first water holding property and fiber (F of the fiber constituting the second fiber layer (2b) ₁ ) and at least the water-holding ability fiber (F ₁₎ of the part contained in the first fibrous layer (2a) often than a ratio of, the inter-woven (交絡) portion between the fibers (P _E) bridging portion of the at least a portion (P _E) In the above, the thermoplastic resin fiber (F ₂ ) is coated with a melt (F _{2M ).}

Description

absorbent article

The present invention relates to an absorbent article such as a sanitary pad.

As a topsheet used for absorbent articles such as sanitary pads, a sheet containing water-retaining fibers that absorb and hold moisture such as cotton fibers is known. For example, Patent Document 1 discloses an absorbent article. As a nonwoven fabric that can be used as a surface material of A nonwoven fabric is disclosed. According to the nonwoven fabric disclosed in this patent document 1, it is supposed that it can utilize suitably also in the field|area in which the conventional nonwoven fabric which consists of cotton fibers, such as a surface material of an absorbent article, has not been used.

Japanese Patent Laid-Open No. 2005-139594

However, as in the nonwoven fabric disclosed in Patent Document 1, only by entangling cotton fibers (water-retaining fibers) and short thermoplastic fibers (thermoplastic resin fibers), the wearer's groin and the skin of its periphery (that is, irritation) When used as a topsheet of an absorbent article that directly comes into direct contact with the skin of a portion where the In addition, during use of the absorbent article, due to friction with the wearer's skin, etc., the entanglement between the fibers is loosened or the water-retaining fibers are broken, so that fluff of the water-retaining fibers occurs on the skin-side surface of the topsheet, and the fluff There was a fear of giving an unpleasant stimulus to the wearer's skin by rising.

Then, an object of this invention is to provide the absorbent article containing the topsheet which is hard to give an unpleasant stimulation to a wearer's skin and is excellent in a feel.

One aspect (Aspect 1) of the present invention is an absorbent article comprising a topsheet,

The surface sheet,

a first fibrous layer comprising water-retaining fibers and forming a skin-side surface of the topsheet;

A second fibrous layer comprising thermoplastic resin fibers and water-retaining fibers and adjacent to the non-skin side of the first fibrous layer and forming a non-skin side surface of the topsheet;

The proportion of the water-retaining fibers in the fibers constituting the first fiber layer is greater than the proportion of the water-retaining fibers in the fibers constituting the second fiber layer,

At least a portion of the water-retaining fibers contained in the first fiber layer is the absorbent article in which at least some of the interlacing portions of the fibers are covered with the melt of the thermoplastic resin fibers.

In the absorbent article of this embodiment, the proportion of water-retaining fibers in the first fibrous layer in the topsheet is greater than the proportion of water-retaining fibers in the second fibrous layer, and at least a portion of the thermoplastic resin fibers contained in the second fibrous layer is Since at least some of the entangled parts of the fibers included in the fiber layer are molten material covering the water-retaining fibers, even if the top sheet contains thermoplastic resin fibers, the thermoplastic resin fibers are not attached to the wearer's skin. It is difficult to touch, and it can make it difficult to give an unpleasant stimulus, such as a stiff touch and a stinging touch, to a wearer.

Further, in the absorbent article of the present embodiment, at least some water-retaining fibers contained in the first fiber layer are coated with a melt of thermoplastic resin fibers in at least some of the interlacing portions of the fibers, so that the fibers in the topsheet Since the entanglement of the water retention fibers is difficult to unravel and the water retention fibers are difficult to break, it is possible to reduce the occurrence of fluffing of the water retention fibers due to the breakage of the entanglement or the breakage of the water retention fibers. This may make it difficult to give to the wearer.

Therefore, the absorbent article of the present embodiment can realize an absorbent article comprising a topsheet excellent in feel that is unlikely to cause unpleasant irritation to the wearer's skin.

Further, in another aspect (Aspect 2) of the present invention, in the absorbent article of Aspect 1, in the thermoplastic resin fiber, one thermoplastic resin fiber is entangled with a plurality of water-retaining fibers, and the one strand is Each of the entangled portions of the thermoplastic resin fibers and the plurality of water-retaining fibers is covered with the melt of the one-stranded thermoplastic resin fibers.

In the absorbent article of this embodiment, each of the entangled portions of the single thermoplastic resin fiber and the plurality of water-retaining fibers is coated with the melt of the single thermoplastic resin fiber, so that the plurality of water-retaining fibers is one strand. Since they are connected via a thermoplastic resin fiber of

In another aspect (Aspect 3) of the present invention, in the absorbent article of Aspect 1 or 2, the melt of the thermoplastic resin fibers is not exposed to the skin-side surface of the first fiber layer.

In the absorbent article of this embodiment, since the melt of the thermoplastic resin fibers is not exposed on the skin-side surface of the first fiber layer, the presence of the melt is hardly perceived by the wearer, and a good feel of the topsheet can be more reliably obtained. there is.

In another aspect (Aspect 4) of the present invention, in the absorbent article according to any one of Aspects 1 to 3, at least the average fiber length of the water-retaining fibers contained in the first fiber layer is the average fiber length of the thermoplastic resin fibers. shorter than

In the absorbent article of this embodiment, the average fiber length of the water-retaining fibers included in the first fiber layer is shorter than the average fiber length of the thermoplastic resin fibers included in the second fiber layer, so that the single thermoplastic resin fiber included in the second fiber layer is Since the number of water-retaining fibers in the contacting first fiber layer increases, the amount of adhesion of the melt of the thermoplastic resin fibers per strand of the water-retaining fibers can be increased, and the above-mentioned water-retaining fibers can be less prone to fluffing.

In another aspect (Aspect 5) of the present invention, in the absorbent article of any of Aspects 1 to 4, the average fiber length of the water-retaining fibers contained in at least the first fiber layer is 5 mm or more and less than 35 mm.

In the absorbent article of this embodiment, since the average fiber length of the water-retaining fibers contained in the first fiber layer is within the specified range, it is easy to maintain the flexibility and texture of the water-retaining fibers while making the above-mentioned fluffing of the water-retaining fibers less likely to occur. , As a result, it is possible to make the surface sheet feel more excellent.

In another aspect (Aspect 6) of the present invention, in the absorbent article of any of Aspects 1 to 5, the thermoplastic resin fiber is a composite fiber, and the composite fiber has a low melting point resin component on the surface of the composite fiber. is exposed to

In the absorbent article of this embodiment, since the thermoplastic resin fiber is a composite fiber, a resin component with a low melting point exposed on the fiber surface (for example, in the case of a core-sheath type composite fiber, a sheath constituting the The resin component, or the resin component on one side in the case of a side-by-side type composite fiber, melts to cover the water-retaining fiber, while a resin component with a high melting point (for example, in the case of a core-sheath type composite fiber, a resin constituting the core) component, in the case of a side-by-side type composite fiber, the resin component on the other side) can maintain a state entangled with the water-retaining fiber or other composite fiber, and a predetermined volume can be maintained as a topsheet.

Thereby, the absorbent article of this aspect makes it easy to ensure the softness|flexibility, texture, cushioning property, etc. with a good surface sheet|seat, while making it hard to produce the fluffing of the water-retaining fiber mentioned above.

In still another aspect (Aspect 7) of the present invention, in the absorbent article of any of Aspects 1 to 6, the topsheet has a crimping portion recessed in the thickness direction from the skin-side surface.

In the absorbent article of the present embodiment, since the topsheet has a crimping portion formed by embossing or the like, the crimping portion holds the water-retaining fibers, making it less likely that the above-mentioned water-retaining fibers will fluff.

In another aspect (Aspect 8) of the present invention, in the absorbent article of any of aspects 1 to 7, the topsheet extends along the longitudinal direction of the absorbent article, and in the width direction of the absorbent article. It has a plurality of convex portions spaced apart from each other, and a plurality of concave portions extending along the longitudinal direction of the absorbent article and located between the convex portions adjacent to each other.

In the absorbent article of this aspect, since the surface sheet on the skin side of the topsheet and the wearer's skin have a small contact area because the topsheet has the specific uneven structure, the thermoplastic resin fibers contained in the topsheet It is possible to further reduce the possibility that unpleasant irritation due to fluffing of the water-retaining fibers is imparted to the wearer's skin.

In another aspect (Aspect 9) of the present invention, in the absorbent article of Aspect 8, the absorbent article further includes an auxiliary sheet positioned on a non-skin side of the topsheet, wherein the topsheet comprises: Each of the plurality of recesses is joined to the auxiliary sheet.

In the absorbent article of this embodiment, since the topsheet is joined to the auxiliary sheet in each of the plurality of recesses, the joint with the auxiliary sheet holds the water-retaining fibers, making it less likely that the above-mentioned water-retaining fibers will fluff. there is.

In another aspect (Aspect 10) of this invention, in the absorbent article of any one of Aspects 1-9, the said water-retaining fiber is organic cotton.

In the absorbent article of this aspect, since the water-retaining fiber is organic cotton excellent in flexibility, texture, etc., the topsheet is easy to ensure good flexibility, texture, etc., and can realize a more excellent feel.

Moreover, when the topsheet contains such organic cotton, there is also an advantage that the wearer of the absorbent article can be nurtured with a sense of security by using a natural material for the topsheet.

In another aspect (Aspect 11) of the present invention, in the absorbent article according to any one of Aspects 1 to 10, the fiber density of the second fiber layer is greater than the fiber density of the first fiber layer.

In the absorbent article of this embodiment, since the fiber density of the second fiber layer is greater than that of the first fiber layer, the fibers constituting the second fiber layer are close to each other, and the capillary phenomenon is more strongly generated in the second fiber layer. Therefore, the liquid excreta excreted on the skin-side surface of the topsheet (that is, the skin-side surface of the first fiber layer) can be quickly drawn into the second fiber layer, and further, the liquid excretion drawn into the second fiber layer. can be rapidly transferred to the non-skin side of the second fiber layer by the thermoplastic resin fibers.

Thereby, the absorbent article of this aspect can ensure favorable water absorption performance, making a top sheet|seat excellent in a feel.

In another aspect (Aspect 12) of the present invention, in the absorbent article of any of aspects 1 to 11, the average distance between the fibers of the second fibrous layer is shorter than the average distance between the fibers of the first fibrous layer.

In the absorbent article of this embodiment, the average distance between the fibers of the second fibrous layer is shorter than the average distance between the fibers of the first fibrous layer, so that the fibers constituting the second fibrous layer are close to each other and capillary phenomenon in the second fibrous layer. can be generated more strongly, so that the liquid excretion excreted on the skin-side surface of the first fiber layer can be quickly drawn into the second fiber layer, and the liquid excretion drawn into the second fiber layer can be absorbed by the thermoplastic resin fiber. It can be rapidly transferred to the non-skin side of the second fibrous layer.

Thereby, the absorbent article of this aspect can ensure favorable water absorption performance, making a top sheet|seat excellent in a feel.

In another aspect (Aspect 13) of the present invention, in the absorbent article according to any one of aspects 1 to 12, the absorbent article has a pair of sides located on the skin side of the topsheet at both ends in the width direction. It further includes a sheet, wherein the pair of side sheets has a coefficient of wet dynamic friction lower than that of the top sheet when wet.

In the absorbent article of the present embodiment, since the pair of side sheets that are easy to come into contact with the skin around the wearer's legs have a lower coefficient of kinetic friction than the topsheet with excellent feel, it is possible to provide a smoother feel as an absorbent article.

ADVANTAGE OF THE INVENTION According to this invention, the absorbent article containing a topsheet excellent in a feel which is hard to give an unpleasant stimulation to a wearer's skin can be provided.

Fig. 1 is a plan view of a sanitary pad 1 according to an embodiment of the present invention as viewed from the topsheet 2 side in the thickness direction T in an expanded state.
FIG. 2 is a cross-sectional view taken along the line II-II of the sanitary pad 1 in FIG. 1 .
FIG. 3 is an enlarged schematic view of the main portion of the first fiber layer 2a of the topsheet 2 .
Fig. 4(a) is an enlarged plan view of the topsheet 2, and Fig. 4(b) is a cross-sectional view taken along the line IVb-IVb of the topsheet 2 in Fig. 4(a).
Fig. 5 is an electron micrograph of the first fiber layer in the topsheet of Example 1 of the present invention.
6 : is a comparative photograph which shows the generation|occurrence|production situation of fluffing with Example 1 of this invention, and Comparative Examples 1 and 2. FIG.

EMBODIMENT OF THE INVENTION Hereinafter, preferred embodiment of the absorbent article of this invention is demonstrated in detail, referring drawings. In the present specification, unless otherwise specified, "an object placed on a horizontal surface in an unfolded state (for example, a sanitary pad (absorbent article), etc.) Seeing” is simply called “flat vision”.

FIG. 1 is a plan view of a sanitary pad 1 according to an embodiment of the present invention as viewed from the topsheet 2 side in the thickness direction T in an expanded state. It is a cross-sectional view taken along the II-II line of the sanitary pad 1 .

As shown in Figs. 1 and 2, the sanitary pad 1 of the present embodiment has a longitudinal direction L, a width direction W, and a thickness direction T, which are orthogonal to each other, and has a width direction. A longitudinal center line C _L (virtual line) passing through the center of (W) and extending in the longitudinal direction (L), and a width direction center line passing through the center of the longitudinal direction (L) and extending in the width direction (W) (C _W ) (virtual line).

In addition, in this specification, in the longitudinal direction L of the sanitary pad 1, the _{proximal side relative to the width direction center line C W} is called the medial side in the longitudinal direction L, and , the distal side relative to the widthwise center line C _W is called the outer side in the longitudinal direction L. Similarly, in the width direction (W) of the sanitary pad (1), the longitudinal center line (C _L) relative to the proximal side and said inner side in the width direction (W), longitudinal center line for (C _L) The distal side relatively to the lateral side is referred to as the outer side in the width direction (W).

In addition, in this specification, the arbitrary direction in the plane including the longitudinal direction L and the width direction W is called "planar direction."

In addition, in the present specification, in the thickness direction T of the sanitary pad 1, when the sanitary pad 1 is worn, the relatively proximal side with respect to the wearer's skin surface is called the skin side, and the sanitary pad 1 is referred to as the skin side. When the pad 1 is worn, the side relatively distal to the skin surface of the wearer is referred to as the non-skin side.

In addition, the definition of such a term is similarly used also for the various members which comprise the sanitary pad 1, and absorbent articles other than the sanitary pad 1 .

[menstrual pad]

As shown in Fig. 1 , a sanitary pad 1 according to an embodiment of the present invention (an example of the "absorbent article" in the present invention) is long and wide in the longitudinal direction L in plan view. It is a substantially rectangular shape short in the direction W, and has a longitudinally elongate shape in which the both ends of the longitudinal direction L protrude so that an arc may be drawn toward the outer side of the longitudinal direction L.

Further, in the central portion of the sanitary pad 1 in the longitudinal direction L, both ends in the width direction W of the sanitary pad 1 face the outer side in the width direction W. It has a pair of wing parts 9 and 9 which protrude so as to form a substantially trapezoidal shape toward the.

In addition, the planar shape of the sanitary pad 1 is not limited to such an aspect, and as long as the length in the longitudinal direction L is longer than the length in the width direction W, it can be used in various usage modes, etc. Any shape (eg, rectangular, elliptical, hourglass-shaped, etc.) may be employed. Moreover, the shape of the wing part 9 is also not limited to said substantially trapezoidal shape, For example, shapes, such as a semicircle shape and a semi-ellipse shape, may be sufficient.

As shown in Fig. 2, the sanitary pad 1 of the present embodiment includes a topsheet 2 forming the skin-side surface of the sanitary pad 1 in the thickness direction T; A back sheet 3 forming the surface of the pad 1 on the non-skin side and an absorbent body 4 disposed between these two sheets are provided as a basic configuration.

In addition, in the present embodiment, the sanitary pad 1 is an auxiliary sheet disposed between the topsheet 2 and the absorber 4 in the thickness direction T, as shown in FIGS. 1 and 2 . (5) and a pair of side sheets 6 and 6 disposed at both ends of the sanitary pad 1 in the width direction W are further provided.

Further, in the present embodiment, each of the pair of side sheets 6 and 6 has a pair of loop portions in which each of both ends of the auxiliary sheet 5 in the width direction W is folded back to the non-skin side. The width of each side sheet 6 is joined so that the skin side surface of the inner side edge part in the width direction W of each side sheet 6 overlaps with the non-skin side surface of 5L, 5L. The non-skin-side surface of the outer side in the direction W is joined to the skin-side surface of the back sheet 3 .

Hereinafter, various members constituting the sanitary pad 1 of the present embodiment will be described in more detail.

Here, FIG. 3 is an enlarged schematic view of the main portion of the first fiber layer 2a of the topsheet 2, FIG. 4(a) is an enlarged plan view of the topsheet 2, and FIG. 4(b). ) is a cross-sectional view taken along the IVb-IVb line of the topsheet 2 in Fig. 4A.

[Surface sheet]

As shown in FIG. 1 , the topsheet 2 extends in the longitudinal direction L from the front side longitudinal end of the sanitary pad 1 to the rear longitudinal end of the sanitary pad 1 in plan view. ), has a substantially rectangular shape in a vertically long plan view. As shown in FIG. 2 , the topsheet 2 is disposed at a position on the skin side in the thickness direction T of the sanitary pad 1 and is a contact surface capable of coming into contact with the wearer's skin (that is, for sanitary use). It is constituted by a liquid-permeable sheet-like member forming the skin-side surface of the pad 1).

In addition, in the present specification, in the longitudinal direction L of the sanitary pad 1, one side that is relatively proximal to the wearer's abdomen when the sanitary pad 1 is worn is referred to as the front side, The other side, which is distal to the wearer's abdomen, is referred to as the posterior side. In connection thereto, sanitary pad (1), as shown in Figure 1, in the longitudinal direction (L), the front-side area (A _F), the central area (A _C) and the rear-side area (A _B) has

And, in this embodiment, the topsheet 2, the water holding property and fiber (F ₁₎ comprising the addition to the surface sheet 2, the first fiber layer (2a) which forms the surface of the skin side of the thermoplastic resin fibers ( A second fibrous layer (2b) comprising F ₂ ) and water-retaining fibers (F ₁ ) and adjoining the non-skin side of the first fibrous layer (2a) and forming the non-skin-side surface of the topsheet (2). It is comprised by the sheet-like member of a two-layer structure.

Further, the topsheet 2 may further include one or more fibrous layers on the non-skin side of the second fibrous layer 2b, or may have a multilayer structure of three or more layers as a whole.

(first fiber layer)

As described above, the first fiber layer 2a contains water-retaining fibers F ₁ .

The water- _{retaining fiber (F 1} ) is not particularly limited as long as it is a fiber having a property of absorbing and retaining water (water-retaining property), and examples thereof include cellulosic fibers and the like.

Moreover, as a cellulose fiber, it will not restrict|limit especially if it is a fiber containing cellulose, For example, natural cellulose fiber, regenerated cellulose fiber, purified cellulose fiber, semi-synthetic cellulose fiber, etc. are mentioned. Examples of natural cellulose fibers include plant fibers, for example, seed hair fibers such as cotton, bast fibers such as hemp, leaf vein fibers such as manila hemp, and fruit fibers such as palms. .

Moreover, as cotton (fiber), Hirsutum-type cotton, such as Upland cotton, Barbadens-type cotton, Arboreum-type cotton, Herbacheum-type cotton, etc. are mentioned, for example. Moreover, as cotton (fiber), organic cotton, pre-organic cotton (trademark), etc. can also be used. However, organic cotton means cotton certified by GOTS (Global Organic Textile Standard).

Examples of the regenerated cellulose fibers include fibers such as rayon, for example, viscose rayon obtained from viscose, polynosic, modal, and copper ammonia rayon obtained from a copper ammonia salt solution of cellulose (also referred to as “cupra”). .

As the purified cellulose fiber, lyocell, specifically, pulp is dissolved in an aqueous solution of N-methylmorpholine N-oxide to obtain a spinning dope solution, and in a dilute solution of N-methylmorpholine N-oxide. Extruded and made into a fiber, etc. are mentioned. In addition, purified cellulose is marketed as, for example, Tencel (trademark).

As a semi-synthetic cellulose fiber, acetate fibers, such as a triacetate and diacetate, etc. are mentioned, for example.

Among the various water-retaining fibers described above, natural cellulose fibers are preferred, cotton is more preferred, and organic cotton is still more preferred from the viewpoints of water-retaining properties and texture, as for water-retaining fibers (F _{1 ).}

If the water-retaining fiber F ₁ is organic cotton excellent in flexibility, texture, and the like, the topsheet 2 is easy to ensure good flexibility, texture, and the like, and a more excellent feel can be realized. Moreover, if the topsheet 2 contains such organic cotton, there is also an advantage that the wearer of the sanitary pad 1 can feel a sense of security by using a natural material for the topsheet 2 . .

(Second Fiber Layer)

A second fibrous layer (2b), as described above, includes a thermoplastic resin fiber (F ₂₎ and the water holding property and fiber (F _1).

The thermoplastic resin fiber (F ₂ ) is not particularly limited as long as it is a fiber (generally hydrophobic fiber) made of a thermoplastic resin. Examples of the thermoplastic resin forming the thermoplastic resin fiber (F ₂ ) include olefin resins such as polyethylene (PE), polypropylene (PP), ethylene-vinyl acetate copolymer (EVA), and polyethylene terephthalate. and known resins such as polyester-based resins such as phthalate (PET) and polylactic acid (PLA), and polyamide-based resins such as 6-nylon. You can do it.

In addition, the structure of the thermoplastic resin fiber (F ₂₎ is not particularly limited, for example, PET (core) / PE (sheath) or PP (core) / PE (sheath) core-sheath type conjugated fibers, such as, side-by- Conjugate fibers, such as a side type composite fiber and a sea-island type composite fiber; hollow fiber; irregular cross-sectional fibers such as flat, Y-shaped, and C-shaped; three-dimensional crimped fibers of latent crimping or current crimping; and split fibers divided by physical load such as water flow, heat, and embossing. Fibers having such a structure may be used alone or in combination of two or more types of fibers.

In addition, in the sanitary pad 1 of the present embodiment, the thermoplastic resin fibers F ₂ of the second fiber layer 2b are PP (core)/PE (sheath) core-sheath composite fibers.

The second is the same as the fibrous layer (2b) water retention fibers (F ₁₎ for, water retention fibers of the first fiber layer (2a) (F ₁₎ that is included in.

Further, in the first fiber layer 2a and the second fiber layer 2b constituting the topsheet 2, the _{ratio of water-retaining fibers F 1} in the fibers constituting the first fiber layer 2a is determined by the second fiber layer. (2b) is larger than the ratio of the water-retaining fibers (F _{1 ) in the fibers constituting the fibers.} Thereby, the top sheet (2) is a thermoplastic resin fiber (F ₂₎ that even if the thermoplastic resin fibers (F ₂₎ is less likely to contact the skin of the wearer including the wearer an unpleasant stimulus, such as a stiff texture or sting irritated feeling It can make it difficult to give

In addition, the ratio of water-retaining fibers (F ₁ ) in the fibers constituting the first fiber layer 2a is, from the viewpoint of enhancing the feel of the topsheet 2, all the constituent fibers of the first fiber layer 2a (a thermoplastic resin to be described later). With respect to the total mass of the fiber (F ₂ , excluding the melt), 70 mass % to 100 mass % is preferable, 80 mass % to 100 mass % is more preferable, and 90 mass % to 100 mass % is further desirable. By setting the proportion of water-retaining fibers (F ₁ ) to 70 mass% or more, the wearer assumes that the skin-side surface of the topsheet 2 formed by the first fiber layer 2a _{contains water-retaining fibers (F 1} ). It becomes easy to recognize, and it becomes easy to realize the good feeling of touch.

In addition, among the fibers constituting the first fibrous layer 2a, fibers _{other than the water-retaining fibers F 1} are not particularly limited as long as they are fibers capable of forming a layer having liquid permeability, for example, the second fibrous layer 2b) The same thermoplastic resin fibers as those contained in the thermoplastic resin fibers (F _{2 ) may be included.}

In the present embodiment, the first fiber layer 2a has _{a ratio of water-retaining fibers (F 1} ) of 100 mass% and contains no fibers other than the _{water-retaining fibers (F 1 ).}

Further, in the present embodiment, the _{average fiber length of the water-retaining fibers F 1} of the second fibrous layer 2b is shorter than the average fiber length of the water-retaining fibers F _{1 of the first fibrous layer 2a.} As a result, at least the fibers constituting the second fibrous layer 2b are more likely to come close to each other (that is, the distance between the fibers is likely to be shortened) and capillary action is more likely to occur. It can be drawn more strongly into the second fibrous layer 2b.

3, the at least a portion of the water holding property and fiber (F ₁₎ included in the first fiber layer (2a), in the bridging portion between the fibers (P _E) bridging portion of the at least a portion (P _E), thermoplastic It is coated with a melt F _2M of resin fibers F _{2 .}

_{As described above, in the sanitary pad 1 of the present embodiment, the ratio of water-retaining fibers (F 1} ) of the first fiber layer (2a) in the topsheet (2) is equal to that of the water-retaining fibers (F) of the second fiber layer (2b). foresight, which is larger than the ratio of _1), the second fiber layer (2b) entangled portion (P _E) of the fibers contained in at least a portion of thermoplastic resin fibers (F _2), a first fiber layer (2a) included in one may be those including, water retention fibers (F ₁₎ the melt because it is a (F _2M), the top sheet (2) is a thermoplastic resin fiber (F ₂₎ for covering at least in part bridging portion (P _E) of, The thermoplastic resin fiber (F ₂ ) is difficult to contact with the wearer's skin, and may make it difficult to give an unpleasant stimulus such as a stiff touch or a stinging touch to the wearer.

Further, in the sanitary pad 1 of the present embodiment, at least a part of the water-retaining fibers F ₁ included in the first fiber layer 2a is at least a part of the entangling part P among the entangling parts P _{E between the fibers. In E} ), by being coated with the melt F _2M of the thermoplastic resin fibers F ₂ , the entanglement between the fibers in the topsheet 2 is difficult to unravel, and the water-retaining fibers F ₁ are less likely to break. , can be less likely to develop a magnetic brush rise of conservatism fiber (F ₁₎ resulting from the breaking of the bridging loosening or water retention fibers (F _1), it is possible to art fluff difficult give unpleasant irritation by occurs to the wearer because it is .

Accordingly, the sanitary pad 1 according to the present embodiment includes the topsheet 2 having an excellent feel that is unlikely to cause unpleasant irritation to the wearer's skin.

In addition, in this specification, the bridging part refers to the part where fibers are entangled, and is a part including the junction point and the periphery of the said junction point.

In addition, in this specification, a molten material means that it is a solidified state through a molten state.

Further, as described above, in the present embodiment, a core-sheath type composite fiber is used as _{the thermoplastic resin fiber F 2 contained in the second fiber layer 2b of the topsheet 2 .} As a result, in the topsheet 2, the core sheath type composite fiber made of a resin component with a low melting point melts _{to cover the water-retaining fiber (F 1} ), while the core portion composed of a resin with a high melting point melts the water-retaining fiber (F). ₁ ) or another core-sheath type composite fiber (thermoplastic resin fiber (F ₂ )) and entangled state can be maintained, and a predetermined volume can be maintained as a topsheet.

Also, when a composite fiber having a low melting point resin component exposed on the surface of the composite fiber, such as a side-by-side composite fiber, is used as the thermoplastic resin fiber, the same effects as described above can be exhibited.

In addition, in the present embodiment, in the above-described thermoplastic resin fiber (F ₂ ), one thermoplastic resin fiber (F ₂ ) is entangled with a plurality of water-retaining fibers (F ₁ ), and the one strand each of the thermoplastic resin fiber (F ₂₎ and entangled portions (P _E) with the water holding property and fiber (F ₁₎ of a plurality of strands, is covered with a molten material (F _2M) of the thermoplastic resin fiber (F ₂₎ of that first strand there is.

Thus, the melt of the first strand of the thermoplastic resin fiber (F ₂₎ and a plurality of strands of conservatism fiber (F ₁₎ between the bridging portion, first strand thermoplastic resin fibers (F ₂₎ for each (P _E) (F _2M) When coated with, since a plurality of water-retaining fibers (F ₁ ) are connected via a single thermoplastic resin fiber (F ₂ ), the above-mentioned annealing of the entanglement or breakage of the _{water-retaining fibers (F 1 )} It can make fluffing more difficult to occur.

Further, in the present invention, it is preferable that the melt of the thermoplastic resin fibers is not exposed to the skin-side surface of the first fiber layer. If the melt of the thermoplastic resin fibers is not exposed on the skin-side surface of the first fiber layer, the presence of the melt is hardly perceived by the wearer, and a good feel of the topsheet can be obtained more reliably.

The fiber length (average fiber length) of the water-retaining fibers (F ₁ ) of the first fibrous layer 2a is not particularly limited as long as the effects of the present invention are not impaired, but at least the water-retaining fibers contained in the first fibrous layer 2a ( the average fiber length of the F _1), is preferably shorter than the average fiber length of the thermoplastic resin fiber (F _{2). If the average fiber length of the water-retaining fibers (F 1} ) included in the first fiber layer (2a) is shorter than the average fiber length of the thermoplastic resin fibers (F ₂ ) included in the second fiber layer (2b), the second fiber layer (2b) _{Since the number of water-retaining fibers (F 1} ) of the first fiber layer (2a) in contact with the contained one strand of the thermoplastic resin fiber (F ₂ ) increases, the melt (F) of _{the thermoplastic resin fibers (F 2} ) per one strand of the water-retaining fiber (F 2 ). it is possible to increase the adhesion amount of _2M), can make it difficult to occur than a magnetic brush occurs for the above-mentioned water retention fibers (F _1).

_{In addition, as a specific average fiber length of the water-retaining fiber F 1} contained in the 1st fiber layer 2a, the average fiber length of 5 mm - 80 mm (that is, 5 mm or more and 80 mm or less) is mentioned, for example. Since the fiber is water-holding ability of the average fiber length (F ₁₎ at least 5mm, water retention foresight fiber (F ₁₎ easy to maintain the flexibility and texture of fibers is easily entangled, it is likely that sufficient strength is obtained. On the other hand, an average fiber length of the water holding property and fiber (F ₁₎ becomes difficult to come out is less than 80mm, a part of water retention fibers (F ₁₎ is extended toward the outside in the width direction (W) of the sanitary pad (1), the art It can be difficult to occur that the liquid excrement leaks from the width direction (W) of the sanitary pad (1) on the water-retaining fiber (F _{1 ) extending outward in the width direction (W).}

_{In addition, the average fiber length of the water-retaining fibers F 1} contained in the first fiber layer 2a is preferably 5 mm or more and 60 mm or less, and more preferably 5 mm or more and less than 35 mm. _{If the average fiber length of the water-retaining fibers (F 1} ) included in the first fiber layer (2a) is 5 mm or more and less than 35 mm, it is _{difficult to cause fluffing of the water-retaining fibers (F 1} ) described above, but the flexibility of the water-retaining fibers (F _{1 )} However, it is easy to maintain the texture, and as a result, the feel of the topsheet 2 can be made more excellent.

In addition, although fineness, average fiber length, etc. in fibers other than the water-retaining fibers (F ₁ ) in the first fiber layer (2a) are not particularly limited, the effect of the _{water-retaining fibers (F 1 ) on the feel} Considering the like, it is preferable to have the same degree as the water-retaining fiber (F ₁ ) (within the range of 0.5 to 2 times). However, in the present embodiment, as described above, the first fiber layer 2a does not contain fibers other than the _{water-retaining fibers F 1 .}

_{The proportion of the water-retaining fibers (F 1} ) in the fibers constituting the second fibrous layer (2b) is not particularly limited as long as it is less than the proportion of the water-retaining fibers (F _{1 ) of the first fibrous layer (2a).} The ratio of the water-retaining fibers F _{1 in} the second fiber layer 2b is, for example, 50 mass% to 90 mass% with respect to the total mass of all constituent fibers of the second fiber layer 2b. When the proportion of the water-retaining fibers (F ₁ ) is 50 mass% or more, the contact feeling in a state in which pressure is applied in the thickness direction (T) can be made good, and when _{the proportion of the water-retaining fibers (F 1} ) is 90 mass% or less , the effect of preventing fluffing by the melt (F _2M ) of the thermoplastic resin fiber (F _{2 ) is more stably exhibited.}

Moreover, 60 mass % - 85 mass % are preferable, and, as for the ratio of the water-retaining fiber (F _{1) of this 2nd fiber layer 2b, 70 mass % - 80 mass % are more preferable.} Correspondingly, the proportion of the thermoplastic resin fibers (F ₂ ) in the second fibrous layer 2b is, for example, 10% by mass to 50% by mass relative to the total mass of all constituent fibers of the second fibrous layer 2b. These are mentioned, 15 mass % - 40 mass % are preferable, and 20 mass % - 30 mass % are more preferable.

In addition, the second fiber layer 2b may contain a third fiber in addition to the _{water-retaining fiber (F 1} ) and the thermoplastic resin fiber (F _{2 ).}

Further, the fiber fineness of the water-holding ability (F ₁₎ contained in the second fibrous layer (2b) is also preferably the same as the first fibrous water retention fibers (F ₁₎ contained in (2a).

The fiber length (average fiber length) of the water-retaining fibers F ₁ of the second fiber layer 2b is not particularly limited as long as the effects of the present invention are not impaired, but similarly to the above-described first fiber layer 2a, the thermoplastic resin It is preferably shorter than the average fiber length of the fibers (F _{2 ).} Since the water holding property and fiber (F ₁₎ the average fiber length is the number of thermoplastic resin fibers (F ₂₎ water-holding ability fiber (F ₁₎ in contact with the thermoplastic resin fiber (F ₂₎ of the average shorter than the fiber length, one strand of many of the art It is possible to increase the adhesion amount of the melt (F _{2M ) of the thermoplastic resin fibers (F 2} ) per one strand of the water-retaining fibers, and it is possible to make it more difficult to produce the _{above-described entanglement between the fibers or breakage of the water-retaining fibers (F 1 ).} .

_{In addition, as a specific average fiber length of the water-retaining fiber F 1} contained in the 2nd fiber layer 2b, the average fiber length of 3 mm - 40 mm is mentioned, for example. Since the fiber is water-holding ability of the average fiber length (F ₁₎ at least 3mm, water retention foresight fiber (F ₁₎ easy to maintain the flexibility and texture of fibers is easily entangled, it is likely that sufficient strength is obtained. On the other hand, if the average fiber length of the water-retaining fibers (F ₁ ) is 40 mm or less, the dynamic freedom of the fibers in the web state during the production of the second fiber layer (2b) is high, and the water-retaining fibers (F ₁ ) are the thermoplastic resin fibers (F ₂ ) Since it is easy to enter the gap between the fibers, the distance between fibers in the second fibrous layer 2b is likely to be shortened, and further, the fiber density of the second fibrous layer 2b is likely to increase.

In the second as in the fiber layer (2b) water retention fibers (F ₁₎ mean fiber length, water retention fibers (F ₁₎ of the first fiber layer (2a) of the above in included in, but are not particularly limited, 5mm or more 35mm It is preferably less than. If the average fiber length of the water- _{retaining fibers F 1} included in the second fiber layer 2b is within such a range, it is easy to maintain the flexibility and texture of the water-retaining _{fibers F 1 , as a result, the surface sheet 2} The feel can be made more excellent.

Further, in the present invention, as the water-retaining fibers F ₁ contained in at least the second fiber layer 2b, a mixed water-retaining fiber obtained by mixing two or more types of water-retaining fibers having different average fiber lengths may be used. For example, the water-retaining fibers are water-retaining fibers having a long average fiber length, and are water-retaining fibers having an average fiber length of 15 mm to 40 mm (preferably 20 mm to 35 mm), and water-retaining fibers having a short average fiber length, the average fiber length It is possible to mix and use water-retaining fibers of 3 mm to 25 mm (preferably 5 mm to 20 mm). When such a mixed water-retaining fiber _{is used as the water-retaining fiber (F 1} ) of the second fiber layer (2b), the water-retaining property and texture of the second fiber layer (2b) are increased by the water-retaining fiber having a long average fiber length, while the average fiber length is increased. The distance between the fibers of the second fibrous layer 2b can be shortened by the short water-retaining fibers.

In addition, when the second fibrous layer 2b includes one or more fibrous layers on the non-skin side, that is, when the topsheet 2 has a multilayer structure of three or more layers as a whole, the liquid permeability is reduced. from the viewpoint than the height, the shorter the distance from the fibrous layer to the surface of the non-skin side of the top sheet 2, a water holding property and fiber (F ₁₎ a relatively low proportion of the addition, the water holding property and fiber (F ₁₎ preferably have a short average fiber length of do.

_{Ease of entanglement between the thermoplastic resin fibers (F 2} ) of the second fiber layer (2b) _{and the water-retaining fibers (F 1} ), which are the main constituent fibers of the first fiber layer (2a), that is, from the first fiber layer (2a) From the viewpoint of ease of transfer of the liquid excreta of the second fiber layer 2a and preventing delamination between the second fiber layer 2b, the fineness of _{the thermoplastic resin fibers F 2 of the second fiber layer 2b is,} It is preferable that the fineness of the water-retaining fibers F _{1 of the first fibrous layer 2a is smaller than that of the water-retaining fibers F 1 .}

In addition, the fiber length (average fiber length) of the thermoplastic resin fibers (F ₂ ) of the second fiber layer 2b is not particularly limited as long as the effects of the present invention are not impaired, for example, 10 mm to 80 mm can be mentioned. there is. _{However, the ease of entanglement between the thermoplastic resin fibers (F 2} ) of the second fiber layer ( 2b ) and the water-retaining fibers ( F ₁ ), which are the main constituent fibers of the first fiber layer ( 2a ), that is, the liquid phase from the first fiber layer ( 2a ) The average fiber length of _{the thermoplastic resin fibers (F 2} ) of the second fiber layer (2b) is, It is preferable to be longer than the average fiber length of the water-retaining fibers _{F 1} of the first fiber layer 2a and the second fiber layer 2b, for example, an average fiber length of 15 mm to 100 mm is mentioned.

The thickness of each of the first fibrous layer 2a and the second fibrous layer 2b is not particularly limited as long as the effects of the present invention are not impaired, and for example, a thickness of 0.05 mm to 4 mm is mentioned, and 0.1 mm The thickness of -3 mm is preferable, and the thickness of 0.2 mm-2 mm is more preferable.

However, when the thickness of the first fibrous layer 2a is relatively thick and the thickness of the second fibrous layer 2b is relatively thin, the first fibrous layer 2a can feel good and the wearer's skin is rewetted. It is easy to suppress the bagging, and when the thickness of the first fiber layer 2a is relatively thin and the thickness of the second fiber layer 2b is relatively thick, the water-retaining fibers (F ₁ ) of the first fiber layer 2a are relatively thick. Since it is easy to be coated with the melt F _{2M of the thermoplastic resin fibers F 2} of the second fiber layer 2b, fluffing caused by the water-retaining fibers F ₁ can be more reliably suppressed. .

The thickness of the topsheet 2 (that is, the total thickness of each fiber layer) is not particularly limited as long as the effects of the present invention are not impaired, and for example, a thickness of 0.1 mm to 5 mm is mentioned, and 0.4 The thickness of mm - 4 mm is preferable, and the thickness of 0.8 mm - 3 mm is more preferable.

Here, the ratio of the fiber types in the sheet such as the fiber layer can be measured as follows.

That is, according to the following procedure, by coloring the water-retaining fiber and the thermoplastic resin fiber in different colors, the ratio of the fiber type can be measured.

(1) The topsheet 2 is cut out to a size of 70 mm x 70 mm to be a sample.

(2) By performing a coloring treatment with reagent KayastainQ (Shikisen, Inc.), only the water-retaining fibers are dyed blue, and only the thermoplastic resin fibers are colored yellow.

(3) By measuring the ratio of blue to yellow when viewed from the skin-side surface (first fiber layer 2a) of the sample in the range of 50 mm x 50 mm with a digital microscope VHX-100 manufactured by Keyence Corporation. , the ratio of the types of fibers in the first fiber layer 2a. On the other hand, the ratio of blue and yellow when viewed from the surface of the non-skin side (second fiber layer 2b) is measured in the range of 50 mm x 50 mm, and the ratio of fiber types in the second fiber layer 2b is taken as .

In judging the magnitude relationship of the ratio of fiber types, when the magnitude relationship of the ratio of blue and yellow is apparent, it can be judged by the appearance, but the magnitude relationship of the ratio of blue and yellow is only apparent. If it cannot be determined, count the number of strands of the fibers colored in each color, and determine the number of strands from the number of strands and the structural characteristics of each fiber (for example, the size and specific gravity of fibers such as fiber length and fineness). It can be judged by calculating the total mass of a fiber and comparing the total mass.

In addition, the distance between constituent fibers in the same sheet|seat as a fiber layer can be measured according to the following measuring method.

(1) The topsheet 2 is cut out to a size of 10 mm x 10 mm to be a sample.

(2) Using a digital microscope VHX-100 (lens VH-Z20R + variable illumination attachment VH-K20) manufactured by Keyence Corporation, photographing magnification: 200 times, measurement area: 1300 µm long × 1735 µm wide, the surface The respective images of the skin-side surface (the first fibrous layer 2a) and the non-skin-side surface (the second fibrous layer 2b) of the sheet 2 are taken. In that case, an image is image|photographed 5 times in total for every 20 micrometers in depth in the range of 0 micrometers - 100 micrometers in depth with respect to each of the surface on the skin side and the surface on the non-skin side.

(3) From each obtained image, the area of a site|part where a fiber does not exist is calculated|required. At that time, depending on whether the luminance in each pixel in each obtained image is lower or higher than a predetermined luminance (threshold), the presence or absence of a fiber in the pixel is determined, and the presence or absence of a fiber in the photographing area in each image is determined. do. However, since only a portion in which no fibers are present is transmitted and brightened (that is, luminance is increased), the area of a portion in which no fibers are present in the imaging area is obtained using this.

(4) The porosity is calculated by subtracting the obtained area of the site in which fibers do not exist from the area (measured area) of the imaging region and dividing by the area (measured area) of the imaging region. Such a calculation is performed on the image of every 20 micrometers in depth, and five porosity is computed.

(5) The average of the five porosity values calculated respectively is the porosity of the skin-side surface (first fibrous layer 2a) and non-skin-side surface (second fibrous layer 2b) of the topsheet 2 do. By comparing the magnitude of this porosity, the magnitude of the distance between fibers can be judged. That is, when the porosity is large, the distance between fibers is large. For example, in the skin-side surface of the topsheet 2 (first fiber layer 2a: for example, a surface of 100% cotton fiber (water-retaining fiber)), the porosity is 25.4%, and the non-skin surface ( Second fiber layer 2b: For example, in the surface of 60% of cotton fibers (water-retaining fibers) and 40% of thermoplastic resin fibers), the porosity is 24.5%.

In addition, the fiber length (average fiber length) of the fibers of the same sheet as the fiber layer is "A7.1.1 A method (standard method) scaled glass plate" of "A7.1 fiber length measurement" of Annex A of JIS L 1015:2010 It can be measured according to "Method for Measuring the Length of Individual Fibers in Phase". In addition, the said method is a test method equivalent to ISO 6989 issued in 1981.

In addition, the basis weight of a sheet|seat like a fiber layer can be measured according to the following measuring method. That is, a fibrous layer for one layer is prepared, the fibrous layer is cut into a size of 5 cm x 5 cm to be a sample, and after drying in an atmosphere of 100° C. or higher, the mass of the sample is measured. Next, the measured mass is divided by the area of the sample to calculate the basis weight of the sample. Let the value obtained by averaging the basis weights of ten samples be the basis weight of the sheet.

In addition, the thickness of a sheet|seat like a fiber layer can be measured according to the following measuring method. That is, an enlarged image in the direction perpendicular to the cut surface of the topsheet 2 is photographed using a digital microscope VHX-100 manufactured by Keyence Corporation. At this time, the enlarged image is an image enlarged at a magnification such that the entire thickness direction T of the topsheet 2 can be photographed, and the magnification is, for example, 20 to 50 times. The obtained enlarged image (three-dimensional image) is converted into a two-dimensional image, and the thickness of each fiber layer is measured in the two-dimensional image. Let the average value of the thicknesses measured at each of the three cut surfaces be the thickness of the topsheet 2 .

Further, in the sanitary pad 1 of the above-described embodiment, it is preferable that the average distance between the constituent fibers of the second fibrous layer 2b is shorter than the average distance between the constituent fibers of the first fibrous layer 2a. If the average distance between the constituent fibers of the second fibrous layer 2b is shorter than the average distance between the constituent fibers of the first fibrous layer 2a, the fibers constituting the second fibrous layer 2b are close to each other, and the second fibrous layer ( Since capillary action can be generated more strongly in 2b), the liquid excreta excreted on the skin-side surface of the first fibrous layer 2a can be quickly drawn into the second fibrous layer 2b, and further, the second fibrous layer The liquid excrement drawn in in (2b) can be rapidly transferred to the non-skin side of the second fiber layer 2b by the _{thermoplastic resin fibers F 2 .}

Accordingly, the sanitary pad 1 having such a configuration can ensure good absorption performance while making the topsheet 2 excellent in feel.

In addition, in the sanitary pad 1 of this embodiment, it is preferable that the fiber density of the second fibrous layer 2b is greater than that of the first fibrous layer 2a. That is, it is preferable that a gradient of fiber density exists in the thickness direction T of the topsheet 2 so that the fiber density increases from the first fiber layer 2a to the second fiber layer 2b.

As described above, when the fiber density of the second fiber layer 2b is greater than that of the first fiber layer 2a, the fibers constituting the second fiber layer 2b are close to each other and form the second fiber layer 2b. Since capillary action can be generated more strongly in the present invention, the liquid excreta supplied to the skin-side surface of the topsheet 2 (that is, the skin-side surface of the first fiber layer 2a) is transferred to the second fiber layer 2b. It can be quickly drawn in, and the liquid excrement drawn into the second fiber layer 2b can be quickly transferred to the non-skin side of the second fiber layer 2b by the _{thermoplastic resin fibers F 2 .}

Accordingly, the sanitary pad 1 having such a configuration can ensure good absorption performance while making the topsheet 2 excellent in feel.

However, when one or more fibrous layers are additionally provided on the surface of the second fibrous layer 2b on the non-skin side, that is, when the topsheet 2 has a multilayer structure of three or more layers, the topsheet It is preferable that the fiber layer closer to the surface of the non-skin side of (2) has a relatively high fiber density. Thereby, the liquid permeability from the fibrous layer relatively located on the skin side to the fibrous layer relatively located on the non-skin side can be further increased, and liquid excretion can be stably transferred by the auxiliary sheet 5 or the absorbent body 4 . can

In addition, the fiber density of a sheet|seat like a fiber layer can be measured according to the following measuring method.

(1) The topsheet 2 is cut out to a size of 10 mm x 10 mm to be a sample.

(2) The cross section parallel to the thickness direction T of the sample is magnified and observed using a scanning electron microscope (manufactured by Nippon Electronics Co., Ltd.: JCM-5100). The magnification is a magnification (for example, 150 to 500 times) that can measure the cross section of 30 to 60 fibers within one plane.

(3) The observation area is divided into three equal parts in the thickness direction T, the skin-side layer, the intermediate layer, and the non-skin layer, the skin-side layer being the first fibrous layer 2a, and the non-skin layer After taking the layer as the second fibrous layer 2b, the number of cross-sections of fibers in each fibrous layer is measured. That is, in a cut surface of a predetermined area, the number of cross-sections of the cut fibers is counted.

(4) The number of cross-sections of the obtained fiber is converted into the number of cross-sections of fibers per mm 2 , and this is referred to as the fiber density (strand/mm 2 ). The measurement is performed at three places, and the average value of the measured values is taken as the fiber density of the sample. That is, as the fiber density, the density of the number of fiber strands is used. In other words, as the fiber density, the number of fibers per unit area in a cross section parallel to the thickness direction T is used.

In addition, as a fiber density, you may use the number of fiber strands per unit volume. The number of fiber strands per unit volume can be calculated|required by analysis by X-ray CT, for example. In the fiber density per unit area and the fiber density per unit volume, the numerical values of the fiber densities are different, but the relative comparison of the fiber densities between fiber layers (for example, comparison of large and small) results in the same result.

Further, as shown in FIG. 3 , in the present embodiment, some of the thermoplastic resin fibers F ₂ included in the second fiber layer 2b are thermally fused to each other. That is, some of the thermoplastic resin fibers (F ₂ ) are joined to each other by thermal fusion at a location where the thermoplastic resin fibers are in contact with each other, and in the second fiber layer (2b), a kind of a matrix _{of the thermoplastic resin fibers (F 2 )} It can be seen that forming

In the sanitary pad 1 having such a configuration, in the second fiber layer 2b, the shape of the second fiber layer 2b is stabilized by _{a portion of the thermoplastic resin fibers F 2 that are heat-sealed to each other.} Since it can be maintained as , even if _{the average fiber length of the water-retaining fibers (F 1} ) included in the second fiber layer (2b) is relatively short, the water-retaining fibers (F ₁ ) are interposed between the thermoplastic resin fibers (F ₂ ) (in the matrix) It can be maintained stably without bias. Thereby, the sanitary pad 1 of the present embodiment can stably transfer the liquid excrement drawn into the second fiber layer 2b to the absorbent body 4 (and the auxiliary sheet 5) without bias. Excellent absorption performance can be exhibited.

In addition, the thermoplastic resin fibers F ₂ of the sanitary pad 1 need not be thermally fused to each other in this way.

Further, as shown in FIG. 4 , in the present embodiment, _{at least a part of the thermoplastic resin fibers F 2} of the second fiber layer 2b is exposed on the skin-side surface of the first fiber layer 2a. That is, the thermoplastic resin fibers F ₂ of the second fibrous layer 2b stably maintain the shape of the second fibrous layer 2b, and at least a portion of the first fibrous layer 2a continuously from the second fibrous layer 2b. ), and further they reach the skin-side surface of the first fibrous layer 2a.

In the sanitary pad 1 having such a configuration, the thermoplastic resin fibers F ₂ of the second fibrous layer 2b are continuously extended to the inside of the first fibrous layer 2a, so that the first fibrous layer 2a ), since the water-retaining fiber (F ₁ ) can be stably held between the thermoplastic resin fibers (F ₂ ), the average distance between the constituent fibers of the first fiber layer (2a) is relatively long, and the first fiber layer (2a) Even in the case where the strength is relatively weak, it is possible to suppress the collapse. Also, the water holding property and fiber (F ₁₎ of the first fiber layer (2a) being held between the thermoplastic resin fiber (F _2), Further, by being covered with a molten material (F _2M) of the thermoplastic resin fiber (F _2), water-holding ability It is possible to effectively suppress the occurrence of fluffing due to the breakage of the fibers (F _{1 ).}

Accordingly, the sanitary pad 1 having such a configuration can make the first fibrous layer 2a of the topsheet 2 more excellent in feel.

_{In addition, a part of the thermoplastic resin fibers (F 2} ) that do not have the water retention properties of the second fiber layer (2b) is present in the first fiber layer (2a), so that the first fiber layer (2a) through the thermoplastic resin fibers (F ₂ ) Since it is possible to promote the transfer of the liquid excreta from the to the second fiber layer 2b, the liquid excretion can be stably transferred to the absorber 4 (and the auxiliary sheet 5).

_{In addition, the thermoplastic resin fibers F 2} of the second fiber layer 2b of the sanitary pad 1 need not be exposed to the skin-side surface of the first fiber layer 2a.

Further, in the present embodiment, as for the fibers constituting the topsheet 2 , the fibers present at both ends in the width direction W of the topsheet 2 are in the width direction W of the topsheet 2 . The fibers present in the central portion are oriented in the longitudinal direction L of the topsheet 2 . That is, in the topsheet 2 of the present embodiment, the fibers present in the central portion in the width direction W have a relatively small orientation in the longitudinal direction L, and fibers present at both ends in the width direction W. , the orientation of the longitudinal direction L is relatively large.

In the sanitary pad 1 having such a configuration, the fiber orientation becomes relatively random in the central portion in the width direction W of the topsheet 2, so that liquid excretion can be diffused substantially concentrically. In addition, since the fiber orientation is formed in the longitudinal direction L at both ends of the topsheet 2 in the width direction W, the liquid excreta reaching the both ends can be diffused in the longitudinal direction L. That is, the sanitary pad 1 can be used as a whole in the planar direction, so that more excellent absorption performance can be exhibited. In addition, at both ends of the topsheet 2 in the width direction W, the number of fiber strands exposed from the edge of the topsheet 2 decreases, so that friction against the wearer's skin is reduced and the feel can be made smoother.

In addition, as for the fiber orientation of the topsheet 2 of the sanitary pad 1, the orientation in the longitudinal direction L at both ends in the width direction W does not need to be relatively large.

As shown in Fig. 1, the sanitary pad 1 is located at a position slightly forward of the central portion in the longitudinal direction L and at the central portion in the width direction W, in the plan view, in the excretory orifice abutment area XA. ) is set. The excretory opening abutting area XA is a region facing or in contact with the wearer's excretory opening when the sanitary pad 1 is worn, and is generally set according to the type or use of the absorbent article. The excretory opening abutting region XA is, for example, at a position slightly near the front of the central portion of the absorbent body 4 in the longitudinal direction L, and is approximately 1 of the total length in the longitudinal direction L of the absorbent body 4 . It has a length of /4 to 1/2, and is approximately 1/2 to 1/3 of the total length in the width direction W of the absorber 4 at the position of the substantially central portion of the absorber 4 in the width direction W. is set to the width of

Further, as in the case of the sanitary pad 1 described above, when the absorbent article is provided with a wing portion, it is common that the excretory opening abutting region is set to overlap the wing portion in the width direction, for example, the excretory opening abutting region. can be set so that the longitudinal center position of the excretory orifice abutting region substantially overlaps with the longitudinal central position of the wing portion in the width direction.

(compression part)

In the present embodiment, as shown in FIG. 1 , the sanitary pad 1 is positioned on both outer sides in the width direction W with respect to the excretory orifice abutting area XA and is continuous or continuous in the longitudinal direction L A pair of crimping portions (compression grooves) 12 and 12 that extend intermittently are provided.

1 , in the present embodiment, the sanitary pad 1 is located on the rear side of each of the pair of crimping portions 12 and 12 in the longitudinal direction L and in the longitudinal direction L ), a pair of crimping portions (compression grooves) 13 and 13, and a heart-shaped annular ( Further, there are provided crimping portions (compression grooves) 11 and 14 having a crimp shape and a plurality of point crimping portions 15 in the excretory opening abutting region XA.

These crimping portions 11 to 15 are formed by crimping the topsheet 2 and the absorber 4 in the thickness direction T by a processing means such as embossing. That is, the top sheet 2, the auxiliary sheet 5, and the absorbent body 4 (specifically, the core wrap 4b and the absorbent core 4a on the skin side of the absorbent body 4) in the thickness direction T It is formed by pressing. As shown in Fig. 2, each of the crimped portions is lightly compressed and formed at a position shallow in depth from the skin-side surface of the topsheet 2 and includes a low-density portion (LPA) having a relatively low fiber density, and strongly compressed. Thus, the topsheet 2 has a high-density portion (HPA) formed at a position deep from the skin-side surface and having a relatively high fiber density. These low-density portions LPA and high-density portions HPA may be referred to as a bottom portion at a shallow position and a bottom portion at a deep position in each crimping portion.

As shown in Fig. 2, the low-density portion LPA and the high-density portion HPA of the crimping portions 11 to 15 are located in the absorbent core 4a, but the high-density portion HPA is a core wrap on the non-skin side. (4b) may be reached.

The shape of the crimping portions 11 to 15 is not particularly limited, and any shape according to the desired liquid diffusivity, deformation inducibility, strength, and the like can be adopted.

The sanitary pad 1 does not need to be provided with such crimping portions 11 to 15, but it is preferable to include at least one crimping portion among the crimping portions 11 to 15.

If the sanitary pad 1 (more specifically, the topsheet 2) has a crimping portion recessed from the skin-side surface in the thickness direction T, the crimping portion contains the water-retaining fibers ( to the F ₁₎ holds, it can be difficult to occur than the magnetic brush rise of conservatism fiber (F ₁₎ of the above.

In addition, in the present embodiment, _{at least a part of the thermoplastic resin fibers F 2} of the second fiber layer 2b is applied to the inner surface of the crimping section in at least one of the crimping sections 11 to 15. is exposed When the sanitary pad 1 has such a configuration, the thermoplastic resin fibers F ₂ are present in the first fiber layer 2a so as to be exposed to the inner surface of the compression part, and thus the first fiber layer 2a also in the compression part. ) of the water-retaining fibers (F ₁ ) can be stably held between the thermoplastic resin fibers (F _{2 ).} Thereby, fluffing due to the water-retaining fibers F ₁ can be made less likely to occur even in the crimping section, and the feel of the first fiber layer 2a in the crimping section can be improved. _{In addition, since a part of the thermoplastic resin fibers F 2} that do not have the water retention properties of the second fiber layer 2b is present in the first fiber layer 2a in the compression section, the thermoplastic resin fibers F ₂ are interposed therebetween in the compression section. Since the transfer of liquid excreta from the first fibrous layer 2a to the second fibrous layer 2b can be promoted, the liquid excretion can be more stably transferred to the absorber 4 (and the auxiliary sheet 5).

In addition, in the sanitary pad 1 , the thermoplastic resin fibers F ₂ do not need to be exposed on the inner surface of the crimping part.

In addition, in the present embodiment, _{at least a portion of the thermoplastic resin fibers F 2} of the second fiber layer 2b is a low-density portion (LPA) of the crimping portion in at least one of the crimping portions 11 to 15. ) is exposed on the surface. If the sanitary pad 1 has such a configuration, the thermoplastic resin fibers F ₂ are present in the first fiber layer 2a so as to be exposed to the surface of the low-density portion LPA, and thus the first in the low-density portion LPA. _{The water-retaining fibers (F 1} ) of the single fiber layer (2a) can be stably held between the thermoplastic resin fibers (F _{2 ).} Thereby, fluffing due to the water-retaining fibers F ₁ can be made less likely to occur even in the low-density portion LPA, and the feel of the first fiber layer 2a in the low-density portion LPA can be improved. _{In addition, since a part of the thermoplastic resin fiber F 2} that does not have the water retention properties of the second fiber layer 2b is present in the first fiber layer 2a in the low-density part LPA, the thermoplastic resin fiber F ₂ is interposed therebetween. Since it is possible to promote the transfer of liquid excreta from the first fibrous layer 2a to the second fibrous layer 2b in the low-density portion LPA, the liquid excretion into the absorber 4 (and the auxiliary sheet 5) is more stable. can be implemented with

In addition, in the sanitary pad 1 , the thermoplastic resin fiber F ₂ does not need to be exposed on the surface of the low-density portion LPA.

(Concave-convex structure)

In the present embodiment, the topsheet 2 has an uneven structure as shown in FIG. 4 .

As shown in Fig. 4(b), the first fibrous layer 2a has a first upper surface 2aE on the upper side (skin side) and a first lower surface 2aF on the lower side (non-skin side) in the thickness direction T. , and the second fiber layer 2b has an upper second upper surface 2bE and a lower second lower surface 2bF in the thickness direction T. The first lower surface 2aF of the first fibrous layer 2a and the second upper surface 2bE of the second fibrous layer 2b are an imaginary boundary between the sheepskin layers, but some of the fibers of the sheepskin layer differ from each other due to entanglement. Since it is in the fibrous layer, it is not a strict boundary.

In addition, the first fiber layer 2a has a first upper surface 2aE, which extends continuously along the longitudinal direction L and is arranged at a predetermined interval in the width direction W, protrudes upward (skin side). A first upper surface 2aE arranged between a plurality of convex portions 21 formed as It has a plurality of concave portions 22 that are recessed.

When the topsheet 2 has a specific concave-convex structure including such a plurality of convex portions 21 and a plurality of concave portions 22, the skin-side surface of the topsheet 2 and the wearer's skin Since the contact area of the surface sheet 2 becomes small, the _{possibility that unpleasant irritation caused by fluffing of the thermoplastic resin fibers (F 2} ) and water-retaining fibers (F ₁ ) contained in the topsheet 2 is given to the wearer's skin is further reduced can do.

In addition, in this embodiment, each of the some convex part 21 has a solid structure, as shown to FIG.4(b). In this way, when each of the plurality of convex portions 21 has a solid structure, each convex portion 21 is less likely to be crushed, and the liquid from each of the convex portions 21 that is easy to contact with the wearer's body to the absorbent body 4 . Since it is excellent in transferability, the dryness of the surface of each convex part 21 can be improved.

On the other hand, the second fibrous layer 2b has a substantially flat structure except for the dimples 23 formed by compression to be described later. However, the second upper surface 2bE of the second fiber layer 2b may slightly rise upward in the thickness direction T at a position corresponding to the convex portion 21 .

Further, the second fibrous layer 2b, like the first fibrous layer 2a, extends continuously along the longitudinal direction L (in a direction opposite to the thickness direction T), and extends in the width direction W ), a plurality of convex portions in which the second lower surface 2bF protrudes downward (non-skin side), arranged with a predetermined interval therebetween, and convex portions extending continuously along the longitudinal direction L and adjacent to each other The second lower surface 2bF disposed therebetween may have a plurality of concave portions dented upward (skin side). In that case, the positions of the convex portions 21 and the concave portions 22 of the first fibrous layer 2a correspond to the positions of the convex and concave portions of the second fibrous layer 2b in the thickness direction T. it is preferable

The first fibrous layer 2a and the second fibrous layer 2b are joined to each other by entanglement. The entangling method includes, for example, a spunlace method or a water jet method. However, the entangling method is not limited to this example, and another entangling method, for example, an air-through method may be used.

Moreover, in this embodiment, the fiber density of the top part 21T of the convex part 21 is S1, the fiber density of the bottom part 22B of the recessed part 22 is S2, and the fiber density of the convex part 21 is S2. When the fiber density of the region MP between the top portion 21T and the bottom portion 22B of the concave portion 22 is S3, the relationship S1 < S3 < S2 is satisfied.

If the sanitary pad 1 has such a configuration, in the topsheet 2, from the top portion 21T of the convex portion 21 having the coarse (low density) fiber density S1, the median (medium density) Since the capillary action tends to act toward the bottom 22B of the recess 22 having a dense (high density) fiber density S2 through the region MP having a fiber density S3 of The liquid excrement excreted on the most skin-side surface (ie, the top portion 21T of the convex portion 21 or its vicinity) is placed in a concave portion ( 22), it can be made easier to draw in with the bottom part 22B. Thereby, liquid excretion is more stably transferred from the skin-side surface of the topsheet 2 to the absorber 4 (and the auxiliary sheet 5) via the non-skin-side surface of the topsheet 2 can do it

Further, the topsheet 2 can make it difficult to generate a liquid backflow of the liquid excrement once absorbed by the above-mentioned fiber density gradient (S1 < S3 < S2), and the fiber density of the convex portion 21 . Since it is possible to provide a soft feel to the wearer by having a low value, the topsheet 2 can improve the water absorption performance while making the feel good.

In addition, the sanitary pad 1 does not need to have the above-mentioned concave-convex structure on the topsheet 2, nor does it need to have the above-mentioned fiber density gradient.

In addition, in the present embodiment, in the topsheet 2, as shown in Fig. 4, in each of the plurality of recesses 22, the first fiber layer 2a and the second fiber layer 2b are embossed. It has the some recessed part 23 formed by crimping|bonding in the thickness direction T by processing means, such as. The plurality of recesses 23 are intermittently arranged along the longitudinal direction L in each of the recesses 22 at equal or non-equal intervals.

In addition, in the recessed part 22 adjacent to each other in the width direction W, the position in which the recessed part 23 is lined up on the same straight line in the longitudinal direction L may be sufficient, and the position which does not line up on the same straight line may be In this embodiment, the some recessed part 23 is arrange|positioned in checkerboard pattern with respect to the recessed part 22, as shown to Fig.4 (a). Moreover, the shape in particular of each planar view of the several recessed part 23 is not restrict|limited, It may be an oval shape like this embodiment, or other arbitrary shapes may be sufficient.

When the sanitary pad 1 has such a configuration, in each of the plurality of recesses 23, the first fibrous layer 2a and the second fibrous layer 2b are compressed in the thickness direction T by compression. By being fixed (that is, the water-retaining fibers F ₁ of the first fibrous layer 2a are compressed), fluffing by the water-retaining fibers F ₁ is less likely to occur, and the feel of the topsheet 2 is further improved. can keep it

In addition, the sanitary pad 1 does not need to include such a plurality of recesses 23 in the topsheet 2 .

(Secondary seat)

In the present embodiment, as shown in FIG. 1 , the auxiliary sheet 5 extends in the longitudinal direction L of the sanitary pad 1 in the longitudinal direction from the front side longitudinal end to the rear side longitudinal end in plan view. ) and has a substantially rectangular shape in a vertically long plan view. As shown in FIG. 2 , the auxiliary sheet 5 is disposed between the topsheet 2 and the absorber 4 in the thickness direction T of the sanitary pad 1 , and the topsheet 2 is It is constituted by a liquid-permeable sheet-like member for transferring the liquid excrement that has passed through to the absorbent body 4 on the non-skin side.

The liquid-permeable sheet-like member that can be used as the auxiliary sheet 5 is not particularly limited as long as the effects of the present invention are not impaired, and examples thereof include a liquid-permeable nonwoven fabric or woven fabric, and a composite sheet laminated therewith. can

In the present embodiment, the auxiliary sheet 5 positioned on the non-skin side of the topsheet 2 includes each of the plurality of recessed portions 22 of the topsheet 2 (more specifically, the recessed portion). The second lower surface 2bF corresponding to each of (22)) is joined to each other by any bonding means such as an adhesive or thermal fusion means. In this way, when the auxiliary sheet 5 and the topsheet 2 are bonded to each other in each of the plurality of recesses of the topsheet 2, the joint between the auxiliary sheet 5 and the topsheet 2 is a water-retaining fiber. (F ₁ ) is held, and fluffing of the water-retaining fiber (F ₁ ) described above can be made more difficult to occur.

In addition, as shown in FIG. 2 , the auxiliary sheet 5 in this embodiment has a slightly larger shape in the width direction W than the topsheet 2, and is formed at both ends in the width direction W. In this case, a pair of loop portions 5L and 5L are formed. The pair of loop portions 5L and 5L has both ends of the auxiliary sheet 5 in the width direction W, respectively, on the inner side and the non-skin side (thickness direction T) of the auxiliary sheet 5 in the width direction W, respectively. ) below) and is formed by folding it back into a loop shape.

Both ends of the folded auxiliary sheet 5 are sandwiched between the top sheet 2 and the pair of side sheets 6 and 6, and the pair of side sheets 6 and 6 face each other. is bonded to each other via a pair of bonding portions (not shown) extending intermittently or continuously along the longitudinal direction L with the inner end of the . In addition, the loop part 5L does not contain an elastic member.

In addition, each of the both ends of the folded auxiliary sheet 5 has the inner surfaces of the loop portion 5L (that is, the surfaces on the non-skin side of the auxiliary sheet 5 before folding) in the longitudinal direction ( They are bonded to each other via a pair of bonding portions extending intermittently or continuously along L).

Usually, in a topsheet containing a large amount of water-retaining fibers, when the edge thereof is rubbed, the water-retaining fibers come loose from the edge and fall off easily. In this embodiment, the auxiliary sheet 5 has a dimension in the width direction W is larger than the dimension in the width direction W of the topsheet 2, that is, both ends of the auxiliary sheet 5 in the width direction W of the topsheet 2 in plan view. A more outer portion extends outward in the width direction W to form a pair of extension portions, and as the pair of extension portions, in the width direction of the auxiliary sheet 5 . Since the above-described pair of loop portions 5L and 5L are formed at both ends of (W), the pair of loop portions 5L and 5L (one pair of loop portions 5L and 5L) pair of extensions), and it is possible to make it difficult to rub both ends and thighs in the width direction W of the topsheet 2 , so that the water-retaining fibers F ₁ described above are the width of the topsheet 2 . It can make it difficult to generate|occur|produce that it loosens from the both ends of the direction W, and falls off.

In addition, when the pair of loop portions 5L and 5L described above are used as the pair of extension portions, the force that the sanitary pad 1 receives from the wearer's thighs is applied to the cushion of the pair of loop portions 5L and 5L. It can be received softly by the action, and the tactile feeling given to the wearer can be made better. In particular, when the water-retaining fiber (F ₁ ) is a cotton fiber, such an effect is remarkable.

In addition, in this embodiment, the auxiliary sheet 5 has a fiber density higher than that of the second fiber layer 2b. If the sanitary pad 1 has such a configuration, the liquid excrement drawn into the second fibrous layer 2b can be more stably transferred to the auxiliary sheet 5 by capillary action, so that the topsheet Liquid excretion can be more stably transferred from (2) to the absorber 4 via the auxiliary sheet 5, and as a result, the absorption performance can be improved while improving the feel of the topsheet 2 there is.

In addition, the sanitary pad 1 does not need to be provided with the auxiliary sheet 5 or the loop part 5L.

In addition, when the auxiliary sheet 5 _{contains water-retaining fibers F 1} corresponding to the top sheet 2 and the top sheet 2 contains cellulosic fibers (preferably cotton fibers), the auxiliary The sheet 5 preferably contains cellulosic fibers (preferably cotton fibers). When the sanitary pad 1 has such a structure, the water-retaining fiber F ₁ having high liquid diffusivity, preferably a cellulosic fiber, and more preferably a cotton fiber, is made of the topsheet 2 Since the first fibrous layer 2a to the auxiliary sheet 5 through the second fibrous layer 2b continuously communicates with each other, by utilizing the liquid diffusion of liquid excretion by these fibers, the auxiliary sheet from the topsheet 2 is Liquid excretion can be more stably transferred to the absorber 4 via (5), and as a result, the topsheet 2 can feel good while the absorption performance can be further improved.

In addition, in the sanitary pad 1, the auxiliary sheet 5 does not need to contain water-retaining fibers, cellulosic fibers, or cotton fibers. In that case, as the auxiliary sheet 5, for example, a nonwoven fabric made of thermoplastic resin fibers can be used.

Further, in the present invention, the dimensional shape or thickness of the auxiliary sheet is not particularly limited as long as the effect of the present invention is not impaired, and any dimensional shape or thickness according to the desired absorption performance or flexibility, etc. may be employed. .

(absorber)

In the above-described embodiment, as shown in FIG. 1 , the absorbent body 4 has a longitudinal center line C _L and a width direction center line C _{W of the} sanitary pad 1 in plan view, respectively. A longitudinally long plane extending in a wide range in the longitudinal direction (L) and in the width direction (W) over the has the shape of a city. As shown in Fig. 2, the absorbent body 4 is disposed between the top sheet 2 and the back sheet 3 in the thickness direction T of the sanitary pad 1 (more specifically, the auxiliary sheet ( 5) disposed between the back sheet 3) and capable of absorbing and retaining liquid excrement such as menstrual blood that has passed through the top sheet 2, and having a predetermined liquid absorption performance and liquid retention performance formed by members.

In the present invention, the absorbent member that can be used as the absorbent is not particularly limited as long as it can absorb and hold at least liquid excretion such as menstrual blood, and any absorbent member known in the art can be employed. Examples of such an absorbent member include one in which at least one absorbent core made of any absorbent material is covered with a core wrap sheet such as a tissue having hydrophilicity. Here, the absorbent material constituting the absorbent core includes, for example, hydrophilic fibers and super absorbent polymers, and more specifically, cellulose fibers such as pulverized pulp, cotton, rayon, and acetate; granular materials made of a superabsorbent polymer such as sodium acrylate copolymer; and mixtures of any combination thereof.

In the above-mentioned embodiment, the absorbent body 4 is comprised by the absorbent core 4a which consists of an absorbent material, and the core wrap 4b which coat|covers it.

Further, when the topsheet 2 contains cellulosic fibers (preferably cotton fibers), the absorbent body 4 corresponds to the topsheet 2 with cellulosic fibers (preferably cotton fibers). It is preferable to include In that case, it is preferable that some of the cellulosic fibers contained in the topsheet 2 are in contact with the cellulosic fibers contained in the absorber 4 . When the sanitary pad 1 has such a configuration, cellulosic fibers with high liquid diffusivity are interposed from the first fibrous layer 2a to the second fibrous layer 2b of the topsheet 2 (in the case In some cases, it exists so as to continuously communicate to the absorber 4 (via the auxiliary sheet 5), so by using the liquid diffusion of liquid excreta by cellulosic fibers, from the top sheet 2 to the absorber 4 Thus, the liquid excrement can be directly diffused, and as a result, the absorption performance can be further improved.

In addition, in the sanitary pad 1, the absorbent body 4 does not need to contain cellulosic fibers or cotton.

In the present invention, the planar view shape, various dimensions, basis weight, etc. of the absorbent body are not particularly limited as long as it can be used as the absorbent body of the absorbent article, and any planar view shape (for example, , rectangle, oval, hourglass shape, etc.), various dimensions, basis weight, etc. can be adopted.

Moreover, in this invention, when an absorbent article has predetermined|prescribed water absorption performance as a whole absorbent article by structural members other than an absorber (for example, a top sheet etc.), an absorbent article must necessarily be such an absorber. does not need to be provided.

(side seat)

In the above embodiment, as shown in Fig. 1 , the pair of side sheets 6 and 6 are arranged at both ends of the sanitary pad 1 in the width direction W in the longitudinal direction L in a plan view. ), and has a pair of band-like shapes. The pair of side sheets 6 and 6 are located on the non-skin side of the topsheet 2 at both ends of the sanitary pad 1 in the width direction W, and are located on the skin side of the topsheet 2 . By a hydrophilic or water-repellent sheet-like member functioning to diffuse the liquid excrement supplied to the sanitary pad 1 in the longitudinal direction L while preventing it from leaking outward in the width direction W of the sanitary pad 1 is formed

The hydrophilic or water-repellent sheet-like member that can be used as the side sheet 6 is not particularly limited as long as it can function as a side sheet, for example, a nonwoven fabric composed of fibers having hydrophilicity or water repellency, a hydrophilic treatment or Nonwoven fabrics subjected to water-repellent treatment, and synthetic resin films having air permeability, and the like are mentioned.

Moreover, in the sanitary pad 1 of this embodiment, the coefficient of kinetic friction of the pair of side sheets 6 and 6 when wet is lower than that of the topsheet 2 when wet. . The pair of side sheets 6 and 6, which are easy to come into contact with the skin around the wearer's leg, have a lower coefficient of kinetic friction than the above-mentioned top sheet 2 which is excellent in feel, so that it is smoother as the sanitary pad 1 It can provide a feel.

Here, the kinetic friction coefficient at the time of wet can be measured according to the following method.

(1) The top sheet and the side sheet of the absorbent article are cut, and a sample of 40 mm in the width direction and 80 mm in the longitudinal direction is cut out. In addition, when these sheets cannot be separated by an adhesive such as a hot melt (HMA) adhesive, the adhesive is washed with toluene and then dried in the air for 24 hours.

(2) The end 10 mm in the longitudinal direction of each sample is fixed to a horizontal board using a gum tape (Aschool Co., Ltd.: "force on the field" fabric tape 0.26 mm thick 50 mm wide x 25 m long roll).

(3) On each sample, a digital force gauge (Nippon Densan Shimpo Co., Ltd., FGP-0.5 (FGP-2)) and a gold canequim (50 mm × 40 mm, JIS) in which an end of 10 mm was joined to the entire surface Attached white cloth for testing fastness to dyeing conforming to L 0803, Japan Standards Association, single fiber cloth) is installed. Furthermore, a weight of 525 g, which is a rectangular parallelepiped with a bottom surface of 35 mm x 25 mm, is placed on it.

(4) The gold gun wetted on average with a predetermined amount of ion-exchanged water is moved 30 mm on the sheet at a speed of 100 mm/min, and the maximum value displayed at that time is used as the coefficient of kinetic friction. At this time, the gold key is applied to the surface of the skin side of each sample.

In this measurement method, the wet skin of the wearer is reproduced by wetting the gold key, and 60% of the wet skin is taken as a reference as the amount of skin moisture reproduced.

Therefore, the predetermined amount of ion-exchanged water is 60 mass % with respect to the mass of the gold key. Specifically, when the gold key of 40 mm x 50 mm is 50 g/m 2 , it is set to 0.06 mL (50 g/m 2 x 0.04 m x 0.05 m x 60%).

In addition, when the sheet cannot be sampled with the above width dimension, a sample is taken with the maximum width that can be taken for measurement. Then, a weight that enters the sheet area and becomes 30 g/cm 2 and a gold key of weight width + 10 mm (connection part of the digital force gauge) are placed on the sheet, and the sheet is moved the maximum distance at a speed of 100 mm/min. Let the maximum value be the coefficient of kinetic friction.

Moreover, in this embodiment, the dynamic friction coefficient at the time of wet of the topsheet 2 is 0.80, and the dynamic friction coefficient at the time of wet of the side sheet 6 is 0.49. Moreover, the difference between the dynamic friction coefficient of the top sheet 2 and the dynamic friction coefficient of the side sheet 6 can be made into 0.1 or more and 0.25 or less, for example. When the difference in the coefficient of kinetic friction is within such a range, the wearer is likely to feel the difference in the surface properties between the topsheet 2 and the sidesheet 6 .

In addition, for the pair of side sheets 6 and 6 having such a low coefficient of dynamic friction, a low friction material is used as a material for forming the side sheets 6 and 6 (eg, constituent fibers of a nonwoven fabric). Alternatively, it can be formed by coating the skin-side surface of a known sheet-like member used as a side sheet with a low-friction material.

In addition, the low friction material that can be used for the side seat is not particularly limited, and for example, an olefin resin such as polyethylene or polypropylene, a silicone resin, a fluororesin such as polytetrafluoroethylene, etc. Low resin, or a resin composition containing these resins, etc. are mentioned.

Further, the pair of side sheets 6 and 6 need not have a coefficient of wet dynamic friction lower than that of the topsheet 2 when wet.

In the present invention, the planar view shape, various dimensions, etc. of each of the pair of side sheets are not particularly limited as long as they can be used as side sheets of the absorbent article, and are arbitrary depending on the desired anti-rust performance, water absorption performance, etc. of the planar view shape, various dimensions, and the like can be employed.

Moreover, since it is not an essential structural requirement in the absorbent article of this invention that an absorbent article is equipped with such a pair of side sheets, an absorbent article does not need to be equipped with such a pair of side sheets.

(back sheet)

In the sanitary pad 1 of the above-described embodiment, the back sheet 3 has a length from the front longitudinal end of the sanitary pad 1 to the rear side in a plan view, as shown in FIG. 1 . While extending in the longitudinal direction L over the sanitary pad 1, in the width direction W of the sanitary pad 1, from one side end in the width direction to the width direction end at the other side in the width direction W It has a longitudinally elongated planar view shape. As shown in FIG. 2 , such a back sheet 3 is disposed at a position on the non-skin side in the thickness direction T of the sanitary pad 1 , and passes through the absorbent body 4 or the absorbent body 4 . It is constituted by a liquid-impermeable sheet-like member that functions to prevent leakage of liquid excrement from the sanitary pad 1 to the outside.

A liquid-impermeable sheet-like member that can be used as the backsheet 3 can function to prevent penetration of liquid excrement such as menstrual blood discharged from the wearer and prevent the liquid excretion from leaking through the wearer's clothing, etc. , is not particularly limited, and for example, any hydrophobic thermoplastic resin fibers (for example, polyolefin fibers such as PE and PP, polyester fibers such as polyethylene terephthalate (PET), core sheath type composite fibers, etc.) hydrophobic nonwoven fabric formed by various composite fibers, etc.); a porous or non-porous resin film formed of a hydrophobic thermoplastic resin such as PE or PP; laminated body which bonded nonwoven fabric to the said resin film; Any liquid-impermeable sheet-like member, such as laminated nonwoven fabrics, such as SMS nonwoven fabric, can be used.

In addition, the planar view shape, various dimensions, and basis weight of the backsheet 3 are not particularly limited as long as they can be used as the backsheet, and any planar view shape, various dimensions, and basis weight according to the desired anti-rust performance, air permeability, strength, etc. etc. can be employed.

Further, in the sanitary pad 1 of the present embodiment, the topsheet 2 is bonded to the auxiliary sheet 5 with an adhesive or the like (eg, a hot melt adhesive or the like), and the auxiliary sheet 5 is and a portion of each of the pair of side sheets 6 and 6 facing the absorber 4 is joined to the absorber 4 with an adhesive or the like, and further, the pair of side sheets 6 and 6 and a portion of each of the absorbent members 4 facing the backsheet 3 is joined to the backsheet 3 with an adhesive or the like.

(adhesive part)

In the present embodiment, as shown in FIG. 2 , the sanitary pad 1 is attached to the wearer's clothing (eg, underwear, etc.) on the non-skin side surface of the back sheet 3 . A plurality of adhesive portions 7 and a pair of adhesive portions 8 and 8 for fixing (1) are further provided.

The plurality of adhesive portions 7 are disposed on the non-skin side surface of the backsheet 3 so as to overlap the absorber 4 in the thickness direction T, and extend continuously in the longitudinal direction L and have a width It has a planar view shape of a plurality of stripes intermittently arranged in the direction W (a substantially rectangular shape of a plurality of strands).

Further, the pair of adhesive portions 8 and 8 are disposed on the surface of the non-skin side of the back sheet 3 so as to overlap the pair of wing portions 9 and 9 in the thickness direction T, in the longitudinal direction. It has a substantially rectangular planar view shape continuously extending to (L).

In addition, these adhesive portions 7 and 8 are not particularly limited as long as the sanitary pad 1 can be fixed to the wearer's clothing, respectively, and may be formed of any adhesive such as a styrenic polymer. can

Moreover, since it is not an essential structural requirement in the absorbent article of this invention that an absorbent article is equipped with such an adhesive part, an absorbent article does not need to be equipped with such an adhesive part.

[Manufacturing method]

Next, the manufacturing method of the topsheet 2 of the sanitary pad 1 which concerns on the above-mentioned embodiment is demonstrated by way of example.

(Second fiber web forming process)

_{First, the water-retaining fibers (F 1} ) and the thermoplastic resin fibers (F ₂ ) for forming the second fiber layer 2b are applied to the first card machine (for example, a dry roller card using a single card or a double card). fed, a second fibrous web corresponding to the second fibrous layer 2b is formed. This second fibrous web is conveyed in the conveying direction MD by a conveying device.

(first fiber web forming process)

_{Next, water-retaining fibers F 1} for forming the first fiber layer 2a are provided to the second card machine (a dry roller card similar to that of the first card machine), which corresponds to the first fiber layer 2a. A first fibrous web is formed.

(Fiber web lamination process)

The formed first fibrous web is laminated on the second fibrous web being conveyed to a conveying device. Thereby, the composite fiber web of the two-layer structure in which the 1st fibrous web and the 2nd fibrous web were laminated|stacked is formed.

In addition, the ratio of each fiber in each fiber web is controllable by the ratio of the raw material fiber supplied to each card machine.

(bridging process)

Next, the composite fiber web having a two-layer structure is subjected to a water jet treatment by a water jet treatment machine, so that the fibers in the composite fiber web are entangled in water flow. Thereby, a composite fiber sheet (spunlace nonwoven fabric) is formed.

In this way, when the fibers in the composite fiber web are entangled as a whole by water flow entanglement, _{it becomes difficult to cause the water-retaining fibers (F 1} ) such as cotton fibers to loosen and fall out, and a good feel is also easily obtained.

Here, in the water jet treatment described above, a high-pressure jet water stream is sprayed from the upper surface side to the composite fiber web mounted on a continuously moving mesh belt, and the fibers in the composite fiber web are entangled by the action of the water flow. will become

In addition, the properties of the composite fiber sheet obtained by the water jet treatment can be appropriately adjusted according to the mass of each fiber web, the hole diameter of the spray nozzle, the number of holes (pitch) of the spray nozzle, the moving speed of the fiber web, and the like.

In addition, the formation method of the fiber web corresponding to each fiber layer is not limited to the said method, For example, a wet method etc. may be employ|adopted. Moreover, the web bonding method is also not limited to the above-mentioned method, either, For example, an air-through method (that is, conveying a composite fiber web to a heating apparatus, in the said heating apparatus, inside a composite fiber web by heating air) A method of entangling fibers), a needle punch method, or the like may be employed.

(drying process)

The composite fiber sheet that has passed through the water jet processing machine is conveyed to a dryer (heated hot air oven) and dried by hot air.

(Heat treatment process)

Moreover, the dried composite fiber sheet is conveyed to a heat processing apparatus (heating type hot air oven), and is heat-processed by the hot air of a predetermined temperature. By this heat treatment, at least a part of the thermoplastic resin fibers F ₂ in the composite fiber sheet melt, and the melt F _2M flows through the composite fiber sheet and is present in a portion corresponding to the first fiber layer 2a. attached to the water holding property and fiber (F ₁₎ or the water holding property and fiber (F ₁₎ of the inter-woven part (P _E) in the composite fiber sheet to be. As a result, in at least the bridging portion of the at least a portion of the water holding property and fiber (F _1), between the fibers contained in the portion corresponding to the first fiber layer (2a) (P _E) bridging portion of the at least a portion (P _E) , covered by a melt (F _2M ) of thermoplastic resin fibers (F _{2 ).}

In addition, conditions of the heat treatment, the thermoplastic resin fiber (F ₂₎ is as long as it can be molten is not particularly limited, the thermoplastic resin fiber (F ₂₎ is a composite fiber such as a core-sheath type conjugated fiber or side-by-side-type conjugated fiber In this case, only the resin component with a low melting point exposed on the surface of the composite fiber (for example, the resin component constituting the sheath in the case of a core-sheath type composite fiber, and the resin component on one side in the case of a side-by-side type composite fiber) It is preferable to employ a melting temperature condition.

Moreover, you may use together the apparatus (namely, a dryer and a heat processing apparatus) used for the drying after the above-mentioned water jet treatment, and the heat processing after that.

(Shaping process)

Next, the composite fiber sheet after heat treatment is supplied to the shaping apparatus while being conveyed in the conveyance direction MD. Here, the shaping apparatus is provided with a pair of shaping rolls which are provided consecutively in the circumferential direction on the outer circumferential surface and have concave and convex portions engaged with each other, and the composite fiber sheet after heat treatment is formed of the pair of shaping rolls. The specific concave-convex structure that is sandwiched between the concave portion and the convex portion and extends in the conveyance direction MD is shaped.

In addition, when the topsheet 2 does not have such a specific uneven structure, you may abbreviate|omit a shaping process.

In this way, the composite fiber shaping sheet for the topsheet 2 is formed. In addition, the composite fiber shaping sheet is laminated with the sheet-like members for other constituent members of the sanitary pad 1 , and then cut into the shape of the sanitary pad 1 to form a topsheet 2 .

The present invention can be applied to various absorbent articles, such as panty liners, (trans)incontinence pads, and disposable diapers, in addition to the sanitary pad of the above-described embodiment. Moreover, the absorbent article of this invention is not limited to the above-mentioned embodiment, the Example mentioned later, etc., within the range which does not deviate from the objective and meaning of this invention, a combination, substitution, a change, etc. are possible as appropriate.

In addition, the nonwoven fabric having the first fiber layer and the second fiber layer, used for the topsheet of the absorbent article of the present invention, is a nonwoven fabric having excellent feel and hardly giving unpleasant irritation to the user's skin. Application to sheet-like members (for example, side sheets, exterior sheets, etc.) is also possible, and furthermore, hygiene products other than absorbent articles (for example, masks, stain-wiping sheets, face masks, cosmetic sheets, Application to nonwoven fabrics used in puffs (for example, cotton puffs) is also possible.

When applied to such a nonwoven fabric, the nonwoven fabric is a nonwoven fabric having a first surface and a second surface,

The nonwoven fabric is

A first fiber layer comprising water-retaining fibers and forming the first surface of the nonwoven fabric;

A second fiber layer comprising a thermoplastic resin fiber and a water-retaining fiber, and adjacent to the second face side of the first fiber layer, forming the second face of the nonwoven fabric;

The proportion of the water-retaining fibers in the fibers constituting the first fiber layer is greater than the proportion of the water-retaining fibers in the fibers constituting the second fiber layer,

At least some of the water-retaining fibers included in the first fiber layer become the nonwoven fabric covered with the melt of the thermoplastic resin fibers in at least some of the interlacing portions of the fibers.

Example

Hereinafter, the present invention will be described in more detail by way of examples and comparative examples, but the present invention is not limited only to these examples.

A topsheet (Example) that can be used for the absorbent article of the present invention and a topsheet (Comparative Example) that do not satisfy the structural requirements of the present invention were produced, and the occurrence of fluff was verified.

Example 1

First, as water-retaining fibers and thermoplastic resin fibers for forming the second fiber layer, respectively, cotton fibers (fiber length 5 mm to 35 mm, basis weight 16 g/m2) and core-sheath composite fibers (core: PP, sheath: PE, fiber length 38 mm; basis weight of 4 g/m 2) was prepared, and these fibers were supplied to the first card machine to form a second fibrous web corresponding to the second fibrous layer (second fibrous web forming step). The mixing ratio (mass ratio) of the cotton fibers and the core-sheath composite fibers in this second fiber web was set to be cotton fibers:core-sheath composite fibers = 60:40.

Next, only cotton fibers (fiber length 20 mm to 35 mm, basis weight 10 g/m 2 ) are prepared as water-retaining fibers for forming the first fiber layer, and these cotton fibers are supplied to a second card machine, so that the first fibers corresponding to the first fiber layer A web was formed (first fiber web forming process).

Then, by laminating the formed first fibrous web on the second fibrous web being transported by a conveying device, a composite fiber web having a two-layer structure in which the first fibrous web and the second fibrous web are laminated is formed (fiber web lamination) After the step), the composite fiber web was subjected to a water jet treatment with a water jet treatment machine to entangle the fibers in the composite fiber web with water flow to obtain a composite fiber sheet (spunlace nonwoven fabric) (interlacing step).

The composite fiber sheet which passed through the water jet processing machine was conveyed to the dryer (heating type hot air oven), and it dried with 70 degreeC hot air (drying process).

Further, the dried composite fiber sheet is conveyed to a heat treatment device (heating hot air oven) and heat-treated with hot air at 130° C. to convert cotton fibers into a melt of core-sheath composite fibers (specifically As a result, it coat|covered with the PE molten material of a sheath part (heat treatment process).

Next, the heat-treated composite fiber sheet is fed to a shaping device provided with a pair of shaping rolls having concave and convex portions that engage with each other, sandwiched between the concave and convex portions of the pair of shaping rolls, and conveyed The uneven structure extending in the direction MD was shaped (shaping process).

The composite fiber shaping sheet in which the concave-convex structure was shaped in this way was cut into a predetermined shape to obtain the topsheet of Example 1.

Comparative Example 1

A topsheet of Comparative Example 1 was obtained in the same manner as in Example 1 except that the heat treatment step and the shaping step were not performed.

Comparative Example 2

What used only cotton fibers (fiber length 20 mm to 35 mm, basis weight 30 g/m 2 ) as fibers for forming the topsheet (that is, the topsheet was a single-layer fibrous layer (cotton fiber layer) without a second fibrous layer); And except not having performed the heat treatment process and the shaping process, it carried out similarly to Example 1, and obtained the topsheet of Comparative Example 2.

Exemplary core-sheath type composite fiber in for the top sheet of Example 1, the first to observe in the fiber layer with a scanning electron microscope, cotton fibers (water retention fibers (F ₁₎₎ the inter-woven part (P _E) between the fibers ( melt (specifically, the thermoplastic resin fiber (F ₂₎₎ has confirmed that, is coated with a melt of the sheath of PE) (F _2M). The confirmation result (that is, the electron micrograph of the 1st fiber layer in the topsheet of Example 1) is shown in FIG.

In addition, for each topsheet of Example 1, Comparative Example 1, and Comparative Example 2, according to the following <Evaluation method for fluffing by a friction fastness test>, the occurrence status of fluffing of each topsheet was comparatively evaluated. . The evaluation result (that is, the comparative photograph which shows the generation|occurrence|production state of fluffing of Example 1 and Comparative Examples 1 and 2) is shown in FIG.

<Evaluation method of fluffing by friction fastness test>

(1) From the nonwoven fabric constituting the topsheet, a measurement target region is cut out to a predetermined size (eg, 80 mm×40 mm) to obtain a measurement sample.

(2) The measurement sample is fixed on the measurement stage of a dyed material friction fastness testing machine (made by Daiei Chemical Seiki Seisakusho).

(3) A weight of 200 g is attached to the upper surface of the friction terminal of the dyeing part friction fastness tester, and a fabric tape forming a friction surface is affixed to the lower surface.

(4) The surface of the measurement sample fixed on the stage for measurement is rubbed with the friction surface in the friction terminal mentioned above. At this time, the number of reciprocation of the friction terminal is 100 and 200 times, and the movement range (reciprocation width) of the friction terminal is 60 mm. In addition, in the items of "0T", "100T", and "200T" shown in FIG. 6, the number of reciprocations of the friction terminal in the friction fastness test (FF) is "0", "100" and "200, respectively. It means "time".

(5) After rubbing with a friction terminal, the state of fluffing on the surface of the measurement sample is observed.

As shown in FIG. 6 , the topsheet of Example 1, in which heat treatment was performed and the cotton fibers were coated with a melt of core-sheath composite fibers in the entangling portions of the fibers, even after rubbing 200 times with a friction terminal, It turns out that fluffing hardly generate|occur|produced and it was excellent in a feel (refer the photograph of column A in FIG. 6).

On the other hand, in the topsheets of Comparative Example 1 and Comparative Example 2, which were not subjected to heat treatment, fluffing occurred only by rubbing 100 times with a friction terminal, and it was found that the feel was decreased (Fig. 6). Refer to the photograph of column B (comparative example 1) and column C (comparative example 2) in ).

1: sanitary pad (an example of an absorbent article) 2: top sheet
2a: first fibrous layer 2b: second fibrous layer
3: back sheet 4: absorbent body
5: Secondary seat 6: Side seat
F ₁ : water-retaining fiber F ₂ : thermoplastic resin fiber
F _2M : melt

Claims (13)

An absorbent article comprising a topsheet, comprising:
The surface sheet,
a first fibrous layer comprising water-retaining fibers and forming a skin-side surface of the topsheet;
A second fibrous layer comprising thermoplastic resin fibers and water-retaining fibers and adjacent to the non-skin side of the first fibrous layer and forming a non-skin side surface of the topsheet;
The proportion of the water-retaining fibers in the fibers constituting the first fiber layer is greater than the proportion of the water-retaining fibers in the fibers constituting the second fiber layer,
The absorbent article, wherein at least a portion of the water-retaining fibers contained in the first fiber layer is coated with the melt of the thermoplastic resin fibers in at least a portion of the entangled portions of the fibers. The method of claim 1,
In the thermoplastic resin fiber, one thermoplastic resin fiber is entangled with a plurality of water-retaining fibers,
The absorbent article, wherein each of the entangled portions of the single thermoplastic resin fiber and the plurality of water-retaining fibers is coated with a melt of the single thermoplastic resin fiber. 3. The method according to claim 1 or 2,
The absorbent article, wherein the melt of the thermoplastic resin fibers is not exposed on the skin-side surface of the first fiber layer. 4. The method according to any one of claims 1 to 3,
The absorbent article, wherein the average fiber length of the water-retaining fibers contained in at least the first fiber layer is shorter than the average fiber length of the thermoplastic resin fibers. 5. The method according to any one of claims 1 to 4,
The absorbent article, wherein the average fiber length of the water-retaining fibers contained in at least the first fibrous layer is 5 mm or more and less than 35 mm. 6. The method according to any one of claims 1 to 5,
The thermoplastic resin fiber is a composite fiber,
The said composite fiber is an absorbent article in which the resin component with a low melting|fusing point is exposed on the surface of the said composite fiber. 7. The method according to any one of claims 1 to 6,
The absorbent article, wherein the topsheet has a crimping portion recessed in the thickness direction from the skin-side surface. 8. The method according to any one of claims 1 to 7,
The surface sheet,
a plurality of convex portions extending along the longitudinal direction of the absorbent article and spaced apart from each other in the width direction of the absorbent article;
An absorbent article extending along the longitudinal direction of the absorbent article and having a plurality of concave portions positioned between convex portions adjacent to each other. 9. The method of claim 8,
The absorbent article further comprises an auxiliary sheet positioned on a non-skin side of the topsheet,
The absorbent article, wherein the topsheet is joined to the auxiliary sheet in each of the plurality of recesses. 10. The method according to any one of claims 1 to 9,
The absorbent article, wherein the water-retaining fiber is organic cotton. 11. The method according to any one of claims 1 to 10,
The absorbent article, wherein the fiber density of the second fibrous layer is greater than the fiber density of the first fibrous layer. 12. The method according to any one of claims 1 to 11,
The absorbent article, wherein the average distance between the fibers of the second fibrous layer is shorter than the average distance between the fibers of the first fibrous layer. 13. The method according to any one of claims 1 to 12,
The absorbent article further includes a pair of side sheets positioned on the skin side of the topsheet at both ends in the width direction;
The said pair of side sheets has a wet dynamic friction coefficient lower than the wet dynamic coefficient of the said topsheet.

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