JPH05285172A - Absorptive article - Google Patents

Abstract

PURPOSE:To improve the hand, liquid permeability, toughness and adhering feel of a surface material sheet by constituting the surface material sheet of nonwoven fabric which contains >=50wt.% core/sheath structure fibers and is thermally fused with the fibers and setting an average adhering width rate for diameters of these fibers and average adhering depth rate, etc., of the fibers with each other to a prescribed range. CONSTITUTION:The surface material sheet 2 is the nonwoven fabric which contains >=50wt.% core/sheath structure fibers and is thermally fused with the fibers. The angle theta at which the fibers of this nonwoven fabric intersect with each other is preferably 30 to 90 deg., the average adhering width rate for the diameters of these fibers in the intersected parts <=0.6, the average adhering depth rate <=0.4 and the average adhering angle of the fibers <=30 deg.. A specific liquid permeable layer 11 may be provided between the surface material sheet 2 and the absorber 4. The thickness under 2.5g loading of this layer is 0.2 to 1mm, the liquid passage time is <=40 seconds, and the Klemm water absorption height is >=50cm for one minute. Further, the surface material sheet 2 may be made into at least a two-layer structure.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to absorbent articles such as sanitary napkins and diapers, and more specifically,
The present invention relates to an absorbent article having a good feel to the skin and having an excellent texture.

[0002]

2. Description of the Related Art In general, absorbent articles such as sanitary napkins and diapers have a liquid-permeable surface material sheet, a liquid-impermeable leakproof material sheet, and an absorbent body arranged between these sheets. It consists of In such an absorbent article, the surface material sheet needs to have a function of coming into contact with the skin and passing body fluid to the absorbent body, and therefore (1) giving a good feeling to the skin (texture), (2) It is required that the discharged body fluid be absorbed and permeated (absorption and permeability), and (3) no damage occurs during use (toughness). In particular, the texture is an important factor in determining the performance of the surface material sheet, and as a means for improving the texture, improvement in softness,
Although there is an improvement in smoothness and a reduction in stickiness, it is especially important to improve the softness. Conventionally, as a method of softening a non-woven fabric used for a surface material sheet, it has been proposed to thin the fibers to be used, to eliminate the bonding portion between the fibers to be used, and to use a soft material.

[0003]

However, the softened non-woven fabrics described above have various problems to be solved. That is, a thin fiber, for example, one using 1 to 1.5 denier fiber,
It is already known that flexibility is improved and cards can be passed. However, such a non-woven fabric is not preferable as a surface material sheet because the non-woven fabric has good flexibility, but a liquid residue is generated during liquid absorption and gives a sticky feeling.

In recent years, many proposals have been made on melt blown non-woven fabrics using micro-denier fibers of 1 denier or less and those using split type fibers, but these non-woven fabrics have poor liquid permeability and surface liquid. Flow easily,
In this state, there is a problem in using it as a surface material sheet. In order to solve these problems, Japanese Patent Laid-Open No. 62-
No. 1,290,54 and Japanese Patent Laid-Open No. 3-51355 propose a nonwoven fabric having fine pores on its surface for improving liquid permeability. However, such a non-woven fabric is not preferable because after the liquid has permeated, a wet back phenomenon causes a liquid residue in the non-woven fabric to give a sticky feeling.
Next, a non-woven fabric (fiber entanglement) in which the bonding points (portions) of the fibers are eliminated has been proposed. As a method for producing such a non-woven fabric, there is a water needling method, a needle punch method, etc. It is well known that you can do it. However, these non-woven fabrics have a problem that they are weak in strength when used as a surface material sheet of an absorbent article.

Further, as a method using a flexible material, there is a spunbond method, and the spunbond method can make a non-woven fabric with only a flexible polypropylene resin (Japanese Utility Model Publication No. 59-9620). 63-31659). However, such a non-woven fabric needs to be embossed to improve its toughness in order to be used as a surface material sheet, and such an embossed non-woven fabric has a poor appearance and a reduced degree of freedom of fibers. Flexibility is reduced.
Further, heat-bonded non-woven fabrics have also been studied for the purpose of softening, but no specific measures have been taken other than reducing the fiber diameter. Therefore, an object of the present invention is to provide an absorbent article which is excellent in texture, liquid permeability, and toughness of a surface material sheet and has a good wearing feeling.
It is another object of the present invention to provide an absorbent article having improved comfortability with improved liquid permeability and liquid drawability in addition to the above characteristics.

[0006]

SUMMARY OF THE INVENTION The present invention provides an absorbent article comprising a liquid-permeable surface material sheet, a liquid-impermeable leak-proof material sheet, and an absorber disposed between these sheets. The surface material sheet is a non-woven fabric containing 50% by weight or more of core / sheath structure fibers, and the fibers being heat-sealed.
The average bonding width ratio W to the fiber diameter of the fibers is 0.6 or less in the portion where the angles θ of the fibers cross each other and are fused to each other in the range of 30 to 90 °, and the fibers of the fibers are The average adhesion depth ratio F with respect to the diameter is 0.4 or less, and the average adhesion angle α at the intersection of the fibers is 30 °.
The first object is achieved by providing an absorbent article characterized by the following.

The present invention also provides a liquid passage layer between the surface material sheet and the absorber, the liquid passage layer having a thickness of 0.2 to 1 mm under a load of 2.5 g, and a liquid passage time. Is 40 seconds or less, and the Klemm water absorption height is 50 cm or more per minute, and the absorber has a thickness of 2 mm or less and a pulp basis weight of 200 g / m ² or less. The second object is achieved by providing a sex article.

Here, the average bonding width ratio W with respect to the fiber diameter means the portion where the resin rises or is affected by melting in the longitudinal cross section of one fiber at the intersection as shown in FIG. 2 (a). It is a value derived from the relational expression W = s / D between s and the fiber diameter D, and the average adhesion depth ratio F is, as shown in FIG. 2B, the overlap of two fibers at the intersection. Height h and fiber diameter D
Is a value derived from the relational expression F = (2D−h) / 2D, and the average adhesion angle α is, as shown in FIG. 2C, from the starting point x of the portion affected by melting of the intersection. Is obtained from the rising angle of the resin at the above-mentioned s / 2 distance y.

When the present inventors obtain a non-woven fabric by heat treatment, when the crossing portion of the fibers is viewed vertically from above with respect to the plane defined by the two fibers, the crossing angle θ ( (Shown in FIG. 3) is mostly 30 to 90 °
Since it is rare that there are more than two fibers in the same intersection, the attention is paid to the texture of the non-woven fabric and the cross-bonded portion of the two fibers. That is,
The surface material sheet according to the present invention is a heat-bonded non-woven fabric known per se, which has good absorbability due to its bulkiness, and strength can be obtained by having an adhesive portion at the intersection of fibers with each other. / A sheath structure fiber is contained in an amount of 50% by weight or more, and a cross-bonded portion between the fibers is formed under the above-described conditions, thereby giving a soft texture. The present inventors have further found that providing a liquid-passing layer having predetermined characteristics between the surface sheet and the absorber is extremely excellent in comfort of the absorbent article, whereby the absorbent article is obtained. In addition, the liquid draw-in property is improved and the feeling of salat is also improved.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the absorbent article according to the present invention will be described below with reference to the drawings. 1 to 3
Shows an embodiment of an absorbent article according to the present invention,
1 is a perspective view of an absorbent article according to the present invention, FIGS. 2 (a) to 2 (c) are cross-sectional views of crossing portions of fibers in a surface material sheet of the absorbent article of FIG. 1, and FIG. FIG. 5 is a plan view of the intersection of the fibers as seen from above perpendicular to the plane determined by the fibers of FIG. In one embodiment, as shown in FIG. 1, an absorbent article (such as a sanitary napkin) 1 has a liquid-permeable surface material sheet 2, a liquid-impermeable leakproof material sheet 3, and a space between these sheets. Although it is the same as the structure known per se in that it is composed of the absorber 4 arranged, it is characterized by the following points.

The surface material sheet 2 of this embodiment, as shown in FIG. 2, contains 50% by weight of the core / sheath structure fiber.
It is a non-woven fabric containing the above and heat-sealing the fibers. As the core component 6 of the core / sheath structure fiber, polyester type such as polyethylene terephthalate and polybutylene terephthalate, polyamide type such as nylon 6, nylon 66, acrylic type and the like having a relatively high melting temperature can be used. As the sheath component 7, an olefinic one such as polyethylene or polypropylene can be used, and the melt index value of the sheath component resin is preferably 1 to 10 g / 10 minutes. The volume ratio of the core / sheath component is 2
0/80 to 80/20, especially 50/50 to 80/2
A ratio of 0 is desirable.

The core / sheath structure fibers are preferably contained in an amount of 50% by weight or more, particularly 80% by weight or more of the whole surface material sheet 2 which is a non-woven fabric. In addition to the core / sheath structure fibers, usual thermoplastic fibers or non-thermoplastic fibers such as rayon and cotton can be appropriately included. The fineness of the above fiber is 2 to 10 denier, and in particular, it is desirable that it is 3 to 6 denier in terms of texture, and the length of the fiber is 25 to 100 mm, especially 35 to 6 denier.
5 mm is desirable. In order to improve the shielding effect of the core / sheath structure fibers, it is preferable to add a filler such as titanium dioxide or talc to either one or both of the core component and the sheath component. It is desirable to add. The amount of the filler added is preferably 1 to 10% by weight.

The fiber having the above structure is heat-treated with a hot air treatment machine or the like to form a heat-bonded nonwoven fabric. In order to obtain the adhesion state of the crossing portion of the fiber described later, during heat treatment,
The heat treatment conditions are set in consideration of the material and volume ratio of the core / sheath structure fiber. Thus, the basis weight of the resulting nonwoven fabric is preferably 12 to 50 g / m ² , and particularly 15 to 30 g / m ² . The angle θ at which the fibers in the obtained non-woven fabric intersect with each other is the angle seen from above perpendicularly to the plane defined by the two fibers, as shown in FIG. In, the average adhesion width ratio W with respect to the fiber diameter is preferably 0.6 or less, and particularly preferably 0.2 to 0.5. Here, the average adhesive width ratio W with respect to the fiber diameter means, as shown in FIG. 2 (a), a portion s and a fiber where the resin rises or is affected by melting in the longitudinal section of one fiber at the intersection. Diameter D
Is a value derived from the relational expression W = s / D. That is, since the fiber 5b having a cross section is cut obliquely at an angle θ with respect to the fiber 5a having a vertical cross section, the diameter of the cut surface is D / c.
osθ. Further, when the entire length L of the entire bonded portion (the portion on the longitudinal cross-section fiber 5a that is swelled by the melting of the sheath resin or is affected by the bonding), the substantial bonded portion width s is 2s = L- ( D / cos θ), and therefore, by setting the adhesive width ratio W = s / D, W = [L
-(D / cos θ)] / 2D, and the total length L of the bonded part
And the angle θ.

Next, the average adhesion depth ratio F with respect to the fiber diameter
Is preferably 0.4 or less, and more preferably 0.35 or less. The average bond depth ratio F is, as shown in FIG. 2B, a relational expression F = (2D−h) / 2D between the overlapping height h (actual measurement) of two fibers at the intersection and the fiber diameter D. Is a value derived by.
In the case of a non-woven fabric mixed with other fibers, since the diameters are different, 2D in the above relational expression is the fiber diameters D ¹ and D ^{2 respectively.}
The sum is D ¹ + D ² . The average adhesion angle α of the fiber is 30
A temperature of less than or equal to 20 °, especially less than or equal to 20 ° is desirable in terms of texture. The average bond angle α of the fibers is, as shown in FIG. 2C, the above s from the starting point x of the portion affected by the melting of the intersection.
It is obtained from the rising angle of the resin at a distance of / 2. That is, the line x connecting the position y of s / 2 and the starting point x
The angle between y and the direction of the fiber 5a in the longitudinal section is α. In the surface material sheet 2 configured in this way, its softness (value by the measurement method described later) is 1 to 15 g / 30 mm,
It is preferably from 3 to 10 g / 30 mm, and in such a range, the flexibility of the surface material sheet is increased and the texture thereof is sufficiently exhibited. Further, the fiber space diameter (r) of the surface material sheet is 60 to
It is 200 μm, preferably 80 to 150 μm, and in such a range, liquid spreading or liquid remaining on the surface material sheet surface becomes difficult (low liquid remaining / improvement of low liquid spreading), and a feeling of salat is obtained. It is applied to the surface of the absorbing surface to suppress the phenomenon called so-called bleeding and improve leakage prevention. Therefore, the surface material sheet 2 having such conditions has excellent strength, flexibility, and gives a good feel to the skin.

In still another embodiment of the present invention,
As shown in FIG. 4, a specific liquid-permeable layer 11 can be provided between the surface material sheet 2 and the absorber 4. Liquid permeable layer 1
No. 1 has a thickness of 0.2 to 1 mm under a load of 2.5 g,
The liquid passage time is 40 seconds or less, and the Klemm water absorption height is 50 cm or more in 1 minute. When the thickness and the liquid passage time are within the above ranges, the liquid passage property of the absorbent surface in the absorbent article 10 is improved, and the liquid passage layer 11 having a porous structure maintains the structure even during the movement, and the liquid is quickly passed. To the absorber 4 to accelerate the fixing of the liquid. Further, when the Klemm water absorption height is within the above range, the liquid remaining on the surface of the surface material sheet 2 is easily transferred to the liquid passage layer 11, and the sensation of the absorbent surface of the article 10 is further enhanced.

As the material of the absorbent body 4, known materials can be used, such as a combination of hydrophilic fiber such as defibrated pulp and a highly water-absorbent polymer, thermoplastic resin, cellulose fiber and the like. Alternatively, a mixture obtained by heat-treating a mixture of superabsorbent polymers can be used, but preferably, the thickness of the absorber 4 is 2 mm or less and the basis weight of pulp is 200 g / m ² or less. When the thickness and the basis weight are within the above ranges, the absorbent article 1 or 10 as a whole is flexible and the wearing feeling is improved.

In the absorbent article 1 or 10,
The surface material sheet 2 may have at least a two-layer structure. In this case, it is important that the upper layer on the skin-contacting side satisfies the conditions of the fiber and the intersection. Then, in order to improve the toughness, the other lower layers preferably have an average adhesive width ratio W of 0.6 or more and an average adhesive angle α of 30 ° or more. The basis weight of the upper layer on the skin contact side is 5 to 30 g / m ² , and the basis weight of the other layers is 7 to 20 g / m 2.
² is also desirable. In the surface material sheet 2 having such a constitution, the toughness and the absorbability are sufficiently retained and the texture is sufficiently observed. Incidentally, the absorbent article 1 or 10
In the above, the leak-proof material sheet 4 is a vapor-permeable sheet that is liquid-impermeable and vapor-permeable that has been stretched by adding a filler to a known thermoplastic resin, and has a feeling similar to underwear, For example, a composite material of a film and a non-woven fabric, a composite material of a film and a woven fabric, or the like is used. Further, the absorbent article 1 or 10 is not limited to a sanitary napkin, but can be used for a disposable paper diaper or the like.

[0018]

[Measurement method-1 (average bond width ratio W, average bond depth ratio F,
And measurement of the average adhesion angle α))

A T330 scanning electron microscope manufactured by JEOL Ltd. was used to measure the average adhesion width ratio W, the average adhesion depth ratio F, and the average adhesion angle α. The measurement sample was taken in a state in which the cross-sectional shape of the fiber was visible, the adhesion portion was magnified 1000 times, and a photograph was taken. From the obtained photograph, the fiber diameter D, the total length L of the bonded portion, the crossing angle θ of the fibers are calculated, and the bonding width W is calculated. Depending on the condition of the photograph, the length s of the adhesive portion can be directly obtained.

The average bond depth ratio F was determined from the height h of the bonded portion and the fiber diameter D. In the case of a non-woven fabric using a plurality of fibers, the fiber diameters (D ¹ , D ² ) of the ^two fibers were obtained and the adhesion depth ratio F was obtained. For the adhesion angle α, the angle between the half position of the length s of the bonded portion and the bonding start point was connected and the extension line of the longitudinal fiber was obtained. From the values obtained above, W,
F is derived as follows. -2s = L- (D / cos [theta])-W = s / D-W = [L- (D / cos [theta])] / 2D-F = (2D-h) / 2D. In the case of a non-woven fabric mixed with other fibers, since the diameters are different, 2D in the above relational expression is the sum D of the respective fiber diameters D ¹ and D ² .
It becomes ¹ + D ² .

[Measurement Method-2 (Measurement of Softness)] Tensilon RTM-100 manufactured by Toyo Baldwin Co., Ltd. was used to measure the softness. As shown in FIG. 6, the measurement sample is a rectangular section of 30 × 150 mm, and the diameter is about 45 mm.
The cylindrical sample 30 is formed, and the overlapping end portions thereof are stapled to soften the buckling strength when the cylindrical sample 30 is compressed. When the sample has fiber orientation, the direction having the orientation is the long side of the rectangle.

[Measurement Method-3 (Measurement of Fiber Space Diameter)] A sheet to be measured is cut into 5 × 5 cm to prepare a sample,
This sample is a microscope (KH-2 made by HiROX
000), the image is magnified 50 times and the image is drawn by a video printer (UP-5000 manufactured by Sony) to obtain a measurement image. FIG. 5A is an enlarged image view of one sample, and FIG. 5B is a measurement image view of the enlarged image view. On the basis of this measurement image, the outside of the fibers in focus is traced with an oil-based marker, and the surface formed there is defined as the fiber space 20. The area occupied by this fiber space is measured by an image analysis and measurement device (Avio EXCEL manufactured by Nippon Avionis)
Sought by. Five arbitrary locations of the sample were selected, and the fiber space diameter (r) was calculated by the following [Equation 1 and 2] from the area (average value) per fiber space at that time.

[0022]

[Equation 1]

[Equation 2] A is the fiber space area (average value), Ai is the measured fiber space area, and N is the measured number.

[0023] The load of the [Measurement method 4 (Measurement of Thickness at load)] The liquid passage layer or absorber such sample piece was cut into 50 × 50cm, 2.5g / cm ² at which the load area 10 cm ² Then, the thickness of the liquid passing layer and the like was determined with a thickness gauge (made by PEACOCK). The measurement is performed 10 times and the average is calculated.
The value was defined as the thickness under a load of 2.5 g / cm ² .

[Measurement Method-5 (Measurement of Liquid Passage Time)] The liquid passage time was measured by the apparatus shown in FIG. First, a sample piece 4 in which the liquid passage layer was cut into a length of 50 mm and a width of 50 mm
0 was prepared, and then this sample piece 40 was clamped and fixed from both upper and lower sides by glass tubes 41 having an inner diameter of 35 mm as shown in FIG. At this time, clips are fixed from both sides via silicone rubber so that the liquid does not seep out from the side during measurement. As a measurement liquid, 1% of 85% aqueous glycerin solution 43 mixed in the ratio shown below was added to a 10 ml beaker 44.
Take 0g and inject gently. Glycerin 85% aqueous solution 43
50% of the opening area of the glass tube 41 after the injection of
The time required for the surface of the sample piece 40 to appear was determined and used as the liquid passage time. The measurement liquid (85% glycerin aqueous solution) was prepared by using glycerin (Wako Pure Chemical Industries, Ltd.) 85
After mixing 15 g of ion-exchanged water with 0.01 g, 0.01 g of Edible Blue No. 1 (Tokyo Chemical Industry Co., Ltd.) was added to give a blue color.

[Measurement Method-6 (Measurement of Creme Absorption Height After 1 Minute and 10 Minutes)] A sample such as a liquid permeable layer is set to 250 m in length
A sample piece 70 is prepared by cutting the sample piece 70 into m and 20 mm in width, and then, as shown in FIG. 8, the sample piece 50 is hung so that the support 51 does not have slack, and both upper and lower sides are fixed. Again 3
A physiological saline 53 is used as a measurement solution up to a height of 40 mm in a rectangular parallelepiped container 52 of 00 × 100 × 50 mm (length, width, depth), and the sample piece 50 is immersed in the physiological saline 53. After dipping the sample piece 50, the height of the regulated liquid absorbed by the sample piece 50 from the liquid surface after 1 minute, and the sample piece 50 after 10 minutes
The height of absorption from the liquid surface was measured. 10 in total
The points were measured in the same manner, and their average values were taken as the absorption height after 1 minute and the absorption height of the physiological saline solution 53 after 10 minutes, respectively.

[Measurement Method-7 (Measurement of Dynamic Absorption)] A female lumbar model 60, in which the obtained sanitary napkin is shown in FIG.
After wearing them as shown in FIG. 10 and wearing shorts, they were made to walk at a walking speed of 100 steps / minute (50 m / minute). 1 minute after walking, 2 g of defibrinated horse blood (infusion rate of 8 g / min) was injected while walking with the tube 61, and 3 minutes later, 3 g of defibrinated horse blood was injected while walking.
After another 3 minutes, 2 g of defibrinated horse blood is infused. After this, 3
Walk for 2 minutes and inject 2 g of defibrinated horse blood while walking, and record the amount of injection when leakage occurs.
The same operation was performed 10 times in total, and the average value of the injection amounts was defined as the dynamic absorption amount.

[Measurement Method-8 (Measurement of Remaining Amount of Liquid and Spread)] The weight of the surface material sheet of the sanitary napkin obtained was measured in advance and mounted on the female waist model 60 shown in FIG. 9 as shown in FIG. After wearing the shorts, they were run for 5 minutes and 30 seconds at a walking speed of 100 steps / minute (50 m / minute). Meanwhile, while walking with the tube 61,
One minute after walking with defibrinated horse blood, 1.5 g (infusion rate 6 g
/ Min), and after 4 minutes and 15 seconds, a total of 3 g of 1.5 g was injected. After the walking, the weight of the surface material sheet was measured, and the weight difference before and after walking was defined as the amount of remaining liquid, and the liquid spreading area of the surface material sheet at this time was expanded.

Examples 1 to 4 (1) Fiber Composition of Nonwoven Fabric (Surface Material Sheet) Polyethylene terephthalate as the core component of the core / sheath structure fiber, polyethylene as the sheath component (density 0.945 g
/ Cm ³ and melt index value 5.5 g / 10 min) at a volume ratio of 60/40, and a fiber having a cut length of 4 denier and 51 mm was used. (2) Basis weight of non-woven fabric: 20 g / m ² (3) Manufacturing conditions The fibrous web having the above-mentioned constitution was heat-treated at each condition temperature with a hot air treatment machine to obtain a non-woven fabric. (4) Evaluation and results The texture, absorbency and tenacity of the obtained nonwoven fabric were evaluated according to the following criteria. The results are shown in Table 1.

<Evaluation criteria for texture, etc.> 5: Very good 4; Good 3; Normal 2; Poor 1; Very bad

Examples 5 to 8 (1) Fiber Composition of Nonwoven Fabric Polyethylene terephthalate as the core component of the core / sheath structure fiber, and polyethylene (density 0.945 g as the sheath component).
/ Cm ³ and melt index value 5.5 g / 10 min) at a volume ratio of 40/60, and a fiber having a cut length of 4 denier × 51 mm was used. (2) Basis weight of nonwoven fabric: 20 g / m ² (3), (4) Same as Examples 1 to 4. The results are shown in Table 1.

(Example 9) (1) Fiber composition of non-woven fabric Upper layer: polyethylene terephthalate as core component of core-sheath structure fiber, polyethylene (density 0.94 as sheath component)
5 g / cm ³ , melt index value 5.5 g / 10 minutes)
A fiber having a volume ratio of 60/40 and a cut length of 4 denier and a cut length of 51 mm was used. Lower layer: polyethylene terephthalate as the core component of the core-sheath structure fiber, polyethylene (density 0.94 as the sheath component
5 g / cm ³ , melt index value 5.5 g / 10 minutes)
A fiber having a volume ratio of 40/60 and a cut length of 4 denier and a cut length of 51 mm was used. (2) Basis weight of nonwoven fabric: 23 g / m ² (upper layer: 8 g / m ² ,
Lower layer 15 g / m ² ) (3), (4) Almost the same as in Examples 1 to 4. The results are shown in Table 1.

Comparative Examples 1 to 4 (1) Fiber Composition of Nonwoven Fabric Polyethylene terephthalate as the core component of the core / sheath structure fiber and polyethylene (density 0.945 g as the sheath component).
/ Cm ³ and melt index value 20 g / 10 min) at a volume ratio of 40/60, and a fiber having a cut length of 4 denier and a cut length of 51 mm was used. (2) Basis weight of nonwoven fabric: 20 g / m ² (3), (4) Same as Examples 1 to 4. The results are shown in Table 1.

Comparative Examples 5 to 8 (1) Fiber Composition of Nonwoven Fabric Polyethylene terephthalate as the core component of the core / sheath structure fiber and polyethylene (density 0.945 g as the sheath component).
/ Cm ³ and melt index value 20 g / 10 min) at a volume ratio of 50/50, and a fiber having a cut length of 4 denier × 51 mm was used. (2) Basis weight of nonwoven fabric: 20 g / m ² (3), (4) Same as Examples 1 to 4. The results are shown in Table 1. (Comparative Example 9) (1) Fiber composition of non-woven fabric Polypropylene as the core component of the core / sheath structure fiber, and polyethylene (density 0.945 g / cm ³ , melt index value 20 g / 10 min) as the sheath component in a volume ratio of 50 / Fifty
The fiber containing 4 denier and 51 mm cut length was used. (2) Basis weight of nonwoven fabric: 25 g / m ² (3), (4) Same as Examples 1 to 4.

[0034]

[Table 1]

(Examples 10 to 13 and Reference Examples 1 to 5) The surface material sheets used in Examples 1 to 9 had the same fiber structure and the softness and fiber space diameter (r )
A sanitary napkin having a surface material sheet having the following and a liquid passage layer having the predetermined characteristics shown in Table 2 was prepared (Examples 10 to 13), and the comfort and the absorbability were evaluated. The results are shown in Table 3. In addition, Reference Examples 1 to 5 are different in the characteristics of the surface material sheet, the liquid-permeable layer, and the absorber. The evaluation criteria such as the feeling of wearing, the feeling of slats, and the texture are shown below. 5; Very good 4; Good 3; Normal 2; Bad 1; Very bad

[0036]

[Table 2]

[0037]

[Table 3]

[0038]

INDUSTRIAL APPLICABILITY The absorbent article according to the present invention can improve the texture, liquid permeability and toughness of the surface material sheet, and can be made to have excellent comfort and absorbability as a whole product.

[Brief description of drawings]

FIG. 1 is a perspective view of an absorbent article according to an embodiment.

2 (a), (b), and (c) are cross-sectional views of intersections of fibers of the surface material sheet of FIG.

FIG. 3 is a plan view of an intersection of fibers of the surface material sheet of FIG.

FIG. 4 is a cross-sectional view of another absorbent article according to this embodiment.

5A is an image copy diagram of a video printer for expressing the fiber space diameter and the like, and FIG. 5B is a diagram of a measurement image obtained by processing the image copy diagram of FIG.

FIG. 6 is a perspective view of a sample for measuring softness.

FIG. 7 is a perspective view of a measuring device used for measuring a liquid passage time.

FIG. 8 is a perspective view of a measuring device used for measuring the Klemm water absorption height.

FIG. 9 is a perspective view of a female essential part model.

FIG. 10 is a perspective view showing a state where a female sanitary model is fitted with a sanitary napkin.

[Explanation of symbols]

 1, 10 Absorbent article 2 Surface material sheet 3 Leak preventive sheet 4 Absorber 5a Longitudinal cross section fiber 5b Transverse cross section fiber 6 Core component 7 Sheath component 11 Liquid permeable layer

Continuation of front page (51) Int.Cl. ⁵ Identification number Office reference number FI Technical display location D01F 8/04 Z 7199-3B D04H 1/54 A 7199-3B

Claims (5)

[Claims] 1. An absorbent article comprising a liquid-permeable surface material sheet, a liquid-impermeable leak-proof material sheet, and an absorber arranged between these sheets, wherein the surface material sheet is a core. / A nonwoven fabric containing 50% by weight or more of sheath structure fibers and heat-bonded to each other, and in the portion where the angle θ between the fibers intersects and fuses in the range of 30 to 90 °, The average bonding width ratio W of the fibers to the fiber diameter is 0.6 or less, the average bonding depth ratio F of the fibers to the fiber diameter is 0.4 or less, and the average bonding of the intersecting portions of the fibers. Angle α is 30 °
An absorbent article characterized by being: 2. The surface material sheet has at least a two-layer structure, wherein the skin contact side layer has a basis weight of 5 to 30 g / m ² , and the other layers have a basis weight of 7 to 20 g / m ^2. The absorbent article according to claim 1, wherein 3. A liquid-permeable surface material sheet, a liquid-impermeable leak-proof material sheet, an absorbent body arranged between these sheets, and further arranged between the surface sheet and the absorbent body. In the absorbent article including a liquid passage layer, the surface material sheet is a non-woven fabric containing 50% by weight or more of core / sheath structure fibers, and the fibers are heat-sealed, and the angle θ between the fibers is Is 30 to 90 ° and intersects and fuses with each other, the average bond width ratio W to the fiber diameter of the fibers is 0.6 or less, and the average bond depth to the fiber diameter of the fibers is The ratio F is 0.4 or less, and the average adhesion angle α at the intersection of the fibers is 30 °.
Below, the liquid passage layer has a thickness of 0.2 to 1 m under a load of 2.5 g.
m, the liquid passage time is 40 seconds or less, and the Klemm water absorption height is 50 cm or more in 1 minute. 4. The absorbent article according to claim 1, wherein the absorber has a thickness of 2 mm or less and a pulp basis weight of 200 g / m ² or less. 5. The surface material sheet has a softness of 1 to 15
The absorbent article according to claim 1 or 3, wherein the fiber space diameter (r) is in the range of 60 to 200 µm at g / 30 mm.