RU2598303C2 - Non-woven material and absorbent article using same - Google Patents

Abstract

FIELD: packaging industry.

SUBSTANCE: non-woven material, comprising a first protruding part protruding towards a first surface side in a horizontal projection of non-woven material in form of a sheet, and a second protruding part protruding towards second surface side as opposite side from first surface, wherein plurality of first protruding parts and second protruding parts, alternately via wall parts, are distributed in two directions from first direction and second direction, in horizontal projection of non-woven material, wherein wall part has radial orientation of fibres, converging towards upper part of second protruding part, substantially at any point in direction of surface formed as first direction and second direction.

EFFECT: increased strength.

25 cl, 17 dwg, 5 tbl

Description

FIELD OF THE INVENTION

The present invention relates to a nonwoven fabric and an absorbent article using it.

BACKGROUND OF THE INVENTION

The development of absorbent products, such as sanitary towels, panty liners and disposable diapers, is carried out in accordance with their functions, using, for example, sheet materials that contain protruding parts on one side; sheet materials that contain strip-shaped protrusions; and sheet materials that contain numerous small holes. For example, Patent Document 1 describes a sheet material with numerous protruding parts in the form of a circular truncated cone, protruding on one side of the sheet.

In this regard, it is possible to produce a sheet material that has suitable cushioning properties for the top sheet. Patent documents 2 and 3 describe sheet materials with a series of small holes on an uneven or rough sheet material. For this reason, the physical properties of the top sheet are improved. In addition, Patent Document 4 describes a laminated sheet in which one side of the sheet material comprises protruding parts extending in the form of strips that form half cylinders having an almost semicircular cross-sectional shape. Due to this, the laminated sheet can be used, for example, as a top sheet with cushioning properties.

List of references

Patent documents

Patent Document 1: JP-A-2008-289662 (JP-A means Unexamined Published Japanese Patent Application)

Patent Document 2: JP-A-03-137258

Patent Document 3: JP-A-08-246321

Patent Document 4: JP-A-2008-25081

SUMMARY OF THE INVENTION

The inventors of the present invention have conducted extensive research and development to create a non-woven material whose shape is different from the forms described above, and to which non-traditional properties and improved functions can be imparted. In particular, the authors of the present invention investigated the production of non-woven material, which contains protruding parts not only on one side of the sheet material, but simultaneously on the upper and lower sides.

In view of the foregoing, the present invention is intended to provide a nonwoven material that has good fluid retraction properties, excellent leakage prevention properties, soft cushioning properties, good recovery from compression deformation, and which can preferably be used as a top sheet, and the like.

The present invention relates to the creation of a non-woven material containing a first protruding part protruding to the first side of the surface in a horizontal projection of the non-woven material in the form of a sheet, and a second protruding part protruding to the second side of the surface as the opposite side from the first surface, in which the plurality of first protruding parts and the second protruding parts, alternately through the wall parts, is distributed in two directions: the first direction and the second direction, in horizontal a projection of the nonwoven material, the wall portion having an orientation of the fibers along a direction connecting the first protruding part and the second protruding part, essentially at any point in the direction of the surface formed by the first direction and the second direction.

Furthermore, the present invention relates to a nonwoven fabric comprising a first protruding portion protruding to a first surface side in a horizontal projection of a sheet-shaped nonwoven fabric and a second protruding portion protruding to a second side of the surface as an opposite side of the first surface in which the first protruding parts and the second protruding parts, alternately through the wall parts, is distributed and continuous in two directions: the first direction and the second occurrence in the horizontal projection of the nonwoven material in which wall portion forms a ring structure, wherein the first projecting portion below the fiber density (r ₁₎ than the fiber density (r ₂₎ of the second protruding portion.

The nonwoven material according to the present invention has good fluid retraction properties, excellent leakage prevention properties, soft cushioning properties, good recovery after compression deformation, and which can preferably be used as a top sheet, and the like.

Other and additional objectives, features and advantages of the present invention will be presented in more detail in the following description with corresponding links to the accompanying drawings.

Brief Description of the Drawings

FIG. 1 is a perspective view schematically illustrating a partial cross section of a top sheet in one embodiment (embodiment 1) of a nonwoven fabric according to the present invention.

FIG. 2 is a cross-sectional view illustrating region II of the nonwoven fabric of FIG. 1 on an enlarged scale.

FIG. 3 is a cross-sectional view illustrating a cross-section along line III-III of the nonwoven fabric of FIG. 1 on an enlarged scale.

FIG. 4 is a cross-sectional view illustrating a cross-section along line IV-IV of the nonwoven fabric of FIG. 1 on an enlarged scale.

FIG. 5 is an explanatory view schematically illustrating a relationship between a first projecting part and a second projecting part in a horizontal projection.

FIG. 6 is an explanatory view schematically illustrating the orientation of the fibers of the wall portion in expanded form.

FIG. 7 is an explanatory view schematically illustrating the orientation of the fibers of the second protruding portion in a horizontal projection.

FIG. 8 is a perspective view schematically illustrating the nonwoven fabric shown in FIG. 1, with a contact flat surface in contact.

FIG. 9 is an explanatory view schematically illustrating a relationship between a first projecting part and a second projecting part in a horizontal projection.

FIG. 10 is an explanatory view illustrating a schematic representation of a nonwoven fabric in this embodiment in compression.

FIG. 11 is a perspective view schematically illustrating a diaper in an embodiment of the present invention.

FIG. 12 is a photograph replacing the drawing, in which the cross section of the sheet made in Example 8, wherein this cross section corresponds to the schematic view shown in FIG. 2, illustrated in a state of low pressure exposure (0.5 gf / cm ² or 0.05 kPa).

FIG. 13 is a photograph replacing the drawing, in which a cross section of the state of the sheet of FIG. 12, when compressed in the thickness direction (T).

FIG. 14 is a photograph replacing the drawing in which the sheet made in Example 8 is illustrated on the first side of the surface.

FIG. 15 is a photograph replacing the drawing, showing a cross section of the sheet made in Example 17, this cross section corresponding to the schematic view shown in FIG. 2.

FIG. 16 is a photograph replacing the drawing, illustrating a microscopic cross-sectional view of a test sample of the nonwoven fabric obtained in Example 22.

FIG. 17 is a photograph replacing the drawing, illustrating a microscopic cross-sectional image when applying pressure to the test sample of the nonwoven material obtained in example 22.

Description of Embodiments

The present invention will now be described in detail with reference to the drawings based on its preferred embodiments.

FIG. 1 is a partial cross-sectional perspective view schematically illustrating a main part of an upper sheet of an absorbent article, which is a preferred embodiment (embodiment 1) of a sheet-shaped nonwoven material according to the present invention. FIG. 2 represents region II of the nonwoven fabric of FIG. 1 on an enlarged scale, and FIG. 3 and FIG. 4 are enlarged cross-sectional views illustrating a cross section along line III-III and a cross section along line IV-IV, respectively. It is preferred that the nonwoven fabric 10 is applied to the top sheet of an absorbent article, such as a sanitary towel or disposable diaper, and used with the first side of surface z ₁ (see FIG. 2) facing toward the user's skin surface and with the second the side of the surface z ₂ located on the side of the absorbent element (not shown in the drawing) of the product. Next, an explanation will be provided with respect to an embodiment in which the nonwoven fabric 10 shown in the above drawings is used, in which the first side of the surface is directed towards the skin surface of the user, as described above. However, the present invention is not intended to be limiting to this embodiment.

The nonwoven fabric 10 in the embodiment preferably has a continuous structure in the direction of the surface. The term “continuous” means that there are no discontinuous parts and small holes are present. Micropores, such as pores between fibers, are not considered small holes. They can be distinguished, for example, by defining small holes as holes in which the equivalent circle diameter is 1 mm or more. Although the aforementioned term "continuous" also extends to a laminated sheet, in the embodiment, a single layer, i.e. non-laminated sheet is an example as a preferred embodiment. Furthermore, the term "continuous" is described as meaning that the surface of the first side surface ₁ and z surface of the second side surface of the nonwoven z ₂ are substantially continuous. Here, the term “substantially continuous” means that no small holes are present, but micropores that are smaller than small holes can be present without losing the effects of the present invention as described above.

On the first side of the surface in a horizontal projection of the nonwoven material 10 in the embodiment, the numerous first protruding parts extend and are located in relation to an inclined intersection in two directions - longitudinal and transverse directions, on the surface (hereinafter, this arrangement is sometimes referred to as the "inclined mesh arrangement"). The mesh arrangement can also be rectangular (90 °), in which case this arrangement can be considered as a rectangular mesh arrangement. In an embodiment, it is preferred that the first direction (x) and the second direction (y) (see FIG. 5) on the surface intersect at an angle of 30 ° to 90 °. In addition, in the embodiment, numerous second protruding parts 2 are formed protruding to the second side of the surface of the nonwoven material. The second protruding parts 2 also have an inclined mesh arrangement, but instead may also have a rectangular mesh arrangement. The preferred range of intersection angles is determined depending on the first protruding parts 1, and thus, it is the same as described above. The first protruding parts 1 and the second protruding parts 2 protrude in opposite directions from the surface of the sheet, and their positions do not coincide either in horizontal projection or in lateral projection. In other words, two types of parts are arranged alternately without overlapping.

The first protruding parts 1 and the second protruding parts 2, which extend and are oriented, respectively, in the first direction (x direction) and the second direction (y direction) on the surface, as described above, are continuous in the shape of the surface without breaking the integrity and constitute a non-woven material 10. Here, the term “continuous without breaking integrity” means that when parts of a certain shape continue to form a surface, it is all continuous as a slowly curving surface without bends or tears. In addition, the arrangement patterns of the aforementioned first protruding parts and the second protruding parts are not limited to the aforementioned parts, and they can be of any configuration that allows the parts to be arranged so that the configuration can continue without breaking integrity. For example, six second protruding portions may be located at the vertices of a hexagon also containing a first protruding portion located in the center, and an arrangement in which the above pattern extends to the surface can be used. In this case, the number of second protruding parts is larger than the number of first protruding parts, and thus a state arises in which the second protruding parts are adjacent to each other. However, since a generally continuous sheet is formed, the definition of the first protruding parts and the second protruding parts arranged “alternately” also extends to this arrangement.

In an embodiment, the first protruding part 1 and the second protruding part 2 are in the form of a truncated cone or hemisphere with a rounded apex. More specifically, the protruding shape of the first protruding part is not pointed, but represents the hemisphere. On the other hand, the protruding shape of the second protruding part is more pointed and represents a round cone or a truncated cone with a rounded apex. In an embodiment, the protruding portions are not limited to the aforementioned shapes and may have any passing shape, and various conical shapes are practical, for example (in the present description, conical shapes are defined broadly as including a round cone, a truncated cone, a pyramid, a truncated pyramid, inclined round cone, etc.). In an embodiment, the first protruding part and the second protruding part hold the internal spaces 1k and 2k, which are similar to their external shapes and represent a truncated cone or hemisphere with a rounded apex. The interior spaces 1k and 2k are separated from each other by the corrugated part 6 and formed as a substantially discontinuous space. On the other hand, the wall portion 3 is between the first protruding part 1 and the second protruding part 2 in the thickness direction of the sheet, and by means of this wall part 3 or the aforementioned corrugated part 6, a sheet structure is formed in which all the protruding parts are continuous. Furthermore, a corrugated or similar corrugated shape in the present invention is defined with respect to the interior spaces 1k of the first protruding parts or the interior spaces 2k of the second protruding parts, which are considered recesses, and means a continuous hill-like protrusion between two recesses, and, as a rule, its surface is oriented in the direction almost coinciding with the direction of the surface of the sheet of nonwoven material.

Next, functions due to the basic structure of the nonwoven fabric in the embodiment described above will be described.

Cushioning properties

The nonwoven material in the embodiment comprises protruding parts not only on one side of the upper and lower sides, but on both sides, and thus exhibits the cushioning properties characteristic of its structure. In the case of protrusions in the form of a strip and protrusions on one side, springiness in the form of a line or surface will inevitably occur, for example. However, according to an embodiment, the bulk cushioning properties maintained at the points (surface contact occurs due to pressure changes and the corresponding contact area increases or decreases) on both sides represent the following uniform movements in three dimensions. In addition, as will be described in more detail below, the wall portion 3 has such an orientation of the fibers that they are oriented in the upward direction of the wall. Therefore, in this position, high elasticity occurs, and suitable cushioning properties are achieved, and the fibers are not destroyed in the thickness direction. In addition, due to the above-described orientation of the fibers of the wall portion, even when the nonwoven material is destroyed by the pressing pressure, and even when the packaging condition and its use are maintained, the initial cushioning capacity is less prone to loss due to its large restoring force.

Absorption capacity

Since spaces can be provided for temporary storage of the fluid due to the function due to the aforementioned good cushioning properties, it is possible to maintain a high absorption rate and appropriately distributed pressure on the absorbent element, and thus, the amount of back flowing fluid from the absorbent element is reduced. In addition, since the recovery force is large, stability of the absorption characteristic is ensured.

Texture

The nonwoven fabric in the embodiment comprises first and second protruding parts in the directions of both sides, and their upper parts are rounded. Therefore, in the case where the nonwoven material is used as the top sheet, even if one of its sides is directed to the skin surface, a good texture is achieved in which the top sheet gently comes into contact with the skin at these points. In addition, the contact points in the form of a surface increase and decrease depending on the pressure during wear, and as a result of this a good texture is obtained, the deformation of the entire top sheet under pressure can be kept at a low level, and, in addition, recovery after strain under pressure. In addition, the non-woven material in the embodiment has a high deformability under light load (compression is easy under light weight), and as a result, good texture and softness can be ensured. Accordingly, a function can be obtained caused by the aforementioned good cushioning properties, which, in combination with dynamic action due to point contact, can provide a particularly good texture. In addition, when the nonwoven material delays excrement or the like, a dry texture is also provided due to the point contact effect described above. To provide a dry texture (absorption effect), the wall portion 3 has an orientation of fibers that are oriented in the upward direction of the wall, and this means that due to the orientation of the fibers in the thickness direction of the wall portion, the fluid moves freely and flows along the fibers, and thus the fluid moves towards the absorbent element, and due to the orientation of the fibers of the wall portion, the reverse movement of the fluid is reduced and a dry texture is provided. In addition, the excellent breathability of the nonwoven fiber itself by maintaining the structure described above and the effect of point contact are useful in preventing skin irritation.

Excretion Retention Properties

The nonwoven fabric 10 in the embodiment comprises first protruding parts 1 and second protruding parts 2 protruding to its both sides. In each part, there is a first internal space 1k and a second internal space 2k formed inside the part. Thus, depending on the physical properties of the fluid and excrement excreted, they can be delayed and neutralized in various ways. For example, as explained in the assumption that the first side z _{1 of the} surface of the nonwoven fabric 10 in FIG. 1 is used for the surface of the skin, excrement with high viscosity and low permeability does not penetrate the top sheet, and excrement is temporarily contained in 2k interior spaces. On the other hand, the released fluid with low viscosity and high permeability penetrates through the upper sheet and then lingers in the interior spaces 1k or lingers on the surface of the sheet of the lower layer if the sheet is located below. In both cases, the parts, primarily in contact with the skin surface, are the upper parts 11 of the first protruding parts, and skin contact is difficult for the aforementioned detained secreted fluids or feces. Due to this, even after urine, feces, menstrual blood and vaginal secretions are secreted, they are largely neutralized, and an extremely good dry texture is maintained.

In an embodiment, the basic structure and features of the nonwoven fabric according to this embodiment will be described in more detail, with the aforementioned basic structures shown in FIG. 5-7 simply illustrate the model form. The nonwoven fabric in the embodiment comprises a first protruding part 1 and a second protruding part 2 (shown by a dashed line), and each of them is represented as a simple circle in FIG. 5. The sizes of the circles vary slightly for difference and do not coincide with the shapes and sizes and the like that are presented in FIG. 1 etc. In the nonwoven fabric according to the embodiment, the first protruding parts 1 and the second protruding parts 2 are arranged in a mesh arrangement. In other words, when the first line k ₁ , the second line k ₂ and the third line k _{3 are} considered in a given direction, the first protruding parts 1 and the second protruding parts 2 on each line are arranged alternately, and when the protruding parts on each line protrude in the direction (direction y) with an inclination to each line on the surface of the sheet, the first protruding parts and the second protruding parts overlap on lines adjacent to each other. In addition, on line n and on line n + 2, the first protruding parts 1 and the second protruding parts 2 overlap with each other. Thus, in the embodiment, when the first protruding parts and the second protruding parts on the line k ₁ move parallel to the y direction, the parts overlap with the first protruding parts and the second protruding parts on the line k ₃ . However, the present invention is not intended to limit this, and the aforementioned first protruding part and second protruding part, which are adjacent to each other, may have gaps.

A wall portion 3 is formed between the first protruding part 1 and the second protruding part 2. When viewed from the protruding part 1 in the center, as shown in FIG. 5, four sections 31, 32, 33 and 34 of the wall part are formed, which are continuous from the second protruding parts 2 from all sides. The four wall sections 31-34 are attached to the wall sections 31 ′, 32 ′, 33 ′ and 34 ′ in the direction of the sheet surface, and they are connected to form an annular wall portion 3. Edge linear parts similar to the elevation exist between the sections 31 ′ , 32 ', 33' and 34 'of the wall part and the first protruding part adjacent to them on the first side of the surface, and these parts are corrugated parts (connecting parts) 6, which form corrugated parts 61-64, corresponding to each of the above sections 31'-34 'wall portion. The term “ring” in the present invention is not limited provided that a continuous infinite shape is formed in the horizontal projection and any shape such as a circle, ellipse, rectangle or polygon in the horizontal projection can be adopted. To preferably maintain a continuous state of the sheet, a circle or ellipse is preferred. In addition, the term “ring” in relation to volumetric forms includes any ring structures having such shapes as a round cylinder, an inclined round cylinder, an elliptical round cylinder, a truncated cone, a truncated inclined cone, a truncated elliptical cone, a truncated quadrangular pyramid and a truncated inclined quadrangular pyramid and to provide a continuous sheet, shapes such as a round cylinder, an elliptical round cylinder, a truncated cone, and a truncated elliptical cone are preferred. A corrugated or similar corrugated shape in the present invention means that when the interior spaces 1k of the first protruding parts or the interior spaces 2k of the second protruding parts are considered recesses, the continuous part is an elevated protruding part between the two recesses, and usually has a surface in a direction almost coincident with the direction of the surface of the sheet of nonwoven material.

FIG. 6 (a) is a view illustrating the wall portion 3 shown in FIG. 5, expanded and expressed in a rectangle model, and the lines g _1a and g _1b illustrated in the drawing represent directions of fiber orientation. To represent the position of the wall parts when the aforementioned annular wall part is considered as a round cylinder, observed as a horizontal section on a surface perpendicular to its generatrix, adding symbols 31-34 to illustrate different positions every 90 ° with respect to the center. As shown in FIG. 6 (a), the wall portion 3 in the embodiment has an orientation along the upward direction of the wall portion (a direction connecting the first protruding part and the second protruding part) at substantially any point in a surface direction defined as a first direction and a second direction. The use of the term “essentially” in this document means that you can partially include provisions without orientation, and the orientation should be considered as all that, to some extent, preferably exhibits each function, as described above. Typically, this means eliminating the case of arranging different orientations in the machine direction and the transverse direction, such as the traditional examples described below, and it is preferable that there is an arrangement with the aforementioned predetermined orientation of the fibers in at least the machine direction and the transverse direction.

As used herein, the term “MD” means the direction in which a sheet material, such as a non-woven material, moves during the manufacturing process. The term "MD" is an abbreviation for "machine direction", which is also called "flow direction." On the other hand, the term "CD" means a direction perpendicular to the machine direction. The term "CD" is the abbreviation of "transverse direction."

In an embodiment, the parts having a stable orientation (line g _1b ) are in the 0 ° position (wall section 31) and in the 180 ° position (wall section 33) which are offset towards the second side of the surface (z ₂ ) . On the other hand, the parts having a stable orientation (line g _1a ) are in the 90 ° position (wall section 32) and in the 270 ° position (wall section 34), which are offset towards the first side of the surface (z ₁ ) . Although sections 31'-34 'of the wall portion are not shown in the drawing, since this complicates the drawing, the same thing happens and the portions generally have the same fiber orientation. However, when the positions of the wall portion illustrating a stable orientation change from 31 to 32, 33, 34, in the respective intermediate positions, the orientation gradually changes, and as a result, the structural orientation of the annular wall portion as a whole is formed. As a result, certain depreciation properties arise, as described above in the embodiment.

On the other hand, for example, in the case where cavities are formed in the nonwoven fabric formed by fusing the fibrous web before molding, by embossing and the like, the fibers are fused to each other before the manufacture of the cavities, and thus the orientation of the fibers is not is changing. As a rule, when the annular wall part (or the wall part that projects in the form of a ring in the Mercator projection is separated every 90 ° in the horizontal projection, as shown in Fig. 6 (b), the orientation of the sheet fibers during fusion remains, and so thus, the orientations of the fibers are different in each divided position.In particular, as shown in the drawing, the fibers are oriented in the upward direction of the wall part (line g _1c ) in its sections 31 and 33, and are oriented in the direction perpendicular to it si (line g ₂ ) in sections 32 and 34 of the wall part. When the nonwoven material is made, the fibers are usually oriented in the machine direction and directly fused, and thus the fibers of the wall part of the cross section in the machine direction are oriented in the corresponding upward direction , while for the cross section in the transverse direction, the fibers are oriented in a direction perpendicular to the upward direction.

FIG. 7 represents the orientation direction (line g ₃ ) of the fibers as a model using the extraction of one of the second protruding parts 2 of FIG. 5. To determine the position, the designations for the wall sections are indicated in their respective positions. As shown in the drawing, the embodiment has a radial orientation of the fibers converging towards the upper part 21 of the second protruding part 2. In other words, to simultaneously explain the relationship with the aforementioned wall part, this shows that the fibers are oriented so that they converge in the direction to the upper part 21 of the second protruding part through the second protruding part 2 from the wall part 3 along the direction of the surface of the sheet. Accordingly, due to the presence of the radial orientation of the fibers towards the upper part 21 of the second protruding part, excellent cushioning properties are created, thus resulting in a protruding part, less prone to fracture, and the shape is easily restored, even though deformation occurs .

Next, a first structural feature (first aspect) of such nonwoven fabric 10 according to the aspect will be described.

As described above, the wall portion is annular according to an aspect, and the orientations of the fibers differ between the portions of the wall portion that the virtual line intersects (for example, the dash-dotted line j ₁ in FIG. 5) passing through a center point in its horizontal section along the first direction on the surface , and between the parts of the wall portion that the virtual line intersects (for example, the dash-dotted line j ₂ in FIG. 5) passing through a central point along a second direction on the surface. This difference is not caused by the configuration in which the orientation of the nonwoven material is maintained before molding, as in the traditional example presented above, and thus the orientation directions are different when observing the wall surface. It is caused by a mode in which the fibers are formed in a state before the fibers are fixed by fusion, and the like. (which is a fibrous web in a state of interweaving of fibers), and thus the orientation of the fibers changes according to the direction of deformation of the web along with the surrounding fibers.

According to an aspect, the orientation of the fibers gradually changes from the first protruding part or the second protruding part to the wall part, in particular in the parts of the wall part that the virtual line crosses (for example, the dash-dot line j ₂ in Fig. 5) along the second direction on the surface. However, when a state of gradual changes is formed, in particular, the structure of the nonwoven material by weaving the fibers (or fusion between the fibers), and there is no large hole in the fibers, the orientation angle gradually changes from the protruding part to the wall part. Preferably, the fibers are in a state in which the hole size as the diameter of the equivalent circle (the diameter of the circle when the measured area is considered the circle), calculated by the area of each hole between the two fibers by analyzing the corresponding image and the like, is 300 μm or less, however the orientation angle around the protruding part is a value close to 0 °, and represents a value close to 90 ° in the wall part.

According to an aspect, the fibers in the wall portion have an orientation of the fibers along a direction connecting the first protruding part and the second protruding part, as described above. Thus, the fibers are oriented in the thickness direction. In the present invention, the fibers are oriented in the thickness direction, and this means that the fibers are oriented in the thickness direction, and, in particular, means that the orientation angle is from 50 ° to 130 °, and the orientation stability is 1.05 or more at measurement in the manner described below. The orientation angle of the fibers of the wall portion is not limited, and the orientation of the fibers has preferably a large orientation angle (70 ° or more) and more preferably an orientation stability of 1.1 or more and an orientation angle of 70 to 110 ° for use as top sheets for sanitary napkins, disposable diapers, etc. for the purpose of absorbing body fluids having a relatively low viscosity.

According to an aspect, the fiber orientation (q ₁₁₎ of the upper portion 11 of the first projecting portion and the fiber orientation (q ₂₁₎ of the upper portion of the second projecting portion is different. Unless otherwise specified, a method for measuring fiber orientation in the present invention is the method illustrated in the example. Here, the meaning of the term “fiber orientation” is a concept that makes up the angle of orientation and stability of the orientation of the fibers. For the orientation of the fibers, the designation of each part is represented as a subscript, and the value with the letter “q” represents the orientation of the fibers. In addition, fiber density (r) and the like. also expressed according to the above rule.

According to an aspect, the upper portion 11 of the first projecting part has a fiber orientation (q ₁₁₎ in the thickness direction, and the upper portion of the second projecting part has the fiber orientation (q ₂₁₎ in the thickness direction. The orientation of the fibers (q ₁₁ ) of the upper part of the first protruding part preferably has an orientation angle of 50 ° to 130 ° and an orientation stability of 1.05 or more. As a result, the fluid moves easily to the second protruding part, and the skin is effectively kept dry on the first side of the surface. The orientation of the fibers (q ₂₁ ) of the upper part of the second protruding part preferably has an orientation angle of 0 ° or more and less than 50 ° or more than 130 ° and 180 ° or less, and orientation stability of less than 1.05. As a result, the tensile strength of the sheet of nonwoven fabric in the machine direction and the transverse direction can be maintained in good balance, which can prevent tearing and stretching of the sheet during its use. When the orientation of the fibers of the upper part of the first protruding part is higher than the orientation of the fibers of the upper part of the second protruding part (q ₁₁ > q ₂₁ ), the first protruding part is more easily deformed under pressure than the second protruding part, and the properties of excellent flexibility and deformation appear as a function .

As for the fiber orientation upper part 21 of the second nonwoven fabric projecting part 10 according to an aspect, the fiber orientation (q _21a) of the first side surface and the fiber orientation (q _21b) of the second side surfaces are substantially identical. This shows that the radial orientation of the fibers toward the upper part 21 of the second protruding part exists on the first side of the surface and the second side of the surface, and the resulting protruding parts are less prone to fracture, and their recovery after deformation is improved. In addition, with regard to the top sheet of the absorbent article, it is easier to transfer fluid from the upper side to the lower side.

According to an aspect, the number of fibers (u ₁ ) of the first protruding part and the number of fibers (u ₂ ) of the second protruding part are essentially the same. Unless otherwise specified, the method for measuring the number of fibers in the present invention is the method described below. As a result of this, curvature is less prone to occur during deformation under the influence of pressure and the like, and it is preferable to restore shape when pressure is relieved. In addition, since the number of fibers in the nonwoven material is almost the same, the values of physical properties, such as the strength of the nonwoven material, are stable, and changes in the sensations of roughness and fiber breakage are less prone to occur, which is preferred.

Essentially the same amounts of fibers can represent the extent to which a functionally significant difference does not occur. The number of fibers has the same definition as surface density or specific gravity, and unless another condition is specified, it is measured during the measurement using the method described below.

In the nonwoven fabric according to the aspect, the fiber density (r ₁₁ ) of the first protruding part 1 is lower than the fiber density (r ₁₂ ) of the second protruding part (r ₁₁ <r ₁₂ ). Unless otherwise specified, the method for measuring fiber density in the present invention is the method described below. As a reference, a measurement of the amount of fibers is also described. The density of the fibers in the first protruding portion is preferably from 30 fibers / mm ² to 150 fibers / mm ² and more preferably from 60 fibers / mm ² to 100 fibers / mm ² . For the above reason, the fiber density in the second protruding portion is preferably from 150 fibers / mm ² to 600 fibers / mm ² and more preferably from 300 fibers / mm ² to 550 fibers / mm ² .

Fiber density measurement

The cut surface of a part of the nonwoven material is observed at high magnification using a scanning electron microscope (the magnification of which is regulated so that cross sections from 30 to 60 fibers can be measured (magnification from 150 to 500 times) (150 times magnification was used in this example) measure the number of cross sections of the fibers and calculate the area of the field of view, wherein the measured number of cross sections of the fibers. Then, this value is converted per 1 mm in the number of cross sections of fibers ^2, and the result determined dissolved as the fiber density (fibers / mm ^2). The measurement is performed at three points, and the average value is defined as the density of the sample fibers. In addition, as observed part center selected midpoint 11a and 11b and the average 21a point and 21b shown in FIG 2. The upper part of the first protruding part, and the second protruding part is the central part.

JCM-5100 Scanning Electron Microscope (trade name) manufactured by JEOL Ltd.

Fiber count

- The thickness (S1) of the upper part of the first protruding part and the thickness (S2) of the upper part of the second protruding part are shown in FIG. 2 is measured by magnification to a size at which the part measured by a VHX-1000 digital microscope manufactured by KEYENCE Corporation is sufficiently visible and can be measured (magnification from 10 to 100 times). The measurement is carried out five times, and the average value is used as the thickness (mm) of the upper part of the first protruding part or the upper part of the second protruding part of the sample.

- The number of fibers per 1 mm ^{2 is} measured using the method for measuring fiber density described above.

- The number of fibers is estimated by measuring the number of fibers (fibers) per thickness (mm) × (per) 1 mm ² . Thus, when the number of fibers per thickness × (by) 1 mm ^{2 of the} upper part of the first protruding part was almost equal to the number of fibers of the upper part of the second protruding part, the number of fibers (fibers / mm ³ ) was also determined equal. The meaning of the term “almost equal” includes the difference within the measurement error.

According to an aspect, as described above, the density of the fibers (r _11a ) on the first side of the surface z ₁ and the density of the fibers (r _11b ) on the second side of the surface z _{2 of the} first protruding part 1 are in relation to r _11a <r _11b , and thus this part has both flexibility and the ability to maintain shape. Both of these functions, as a rule, with a low probability exist in such a nonwoven material, however, due to the creation of a certain high and low density of fibers, as described above, a part with structural deformation due to compression from the outside arises, and in this part a structure that retains this part, and the above functions are provided. For example, in the upper part 11 of the first protruding part of the fiber on the second side of the surface are "dense", and thus, the relatively rigid part is included in the work as a bridge support. The first side of the surface is soft, generally non-rigid and retains sufficient flexibility.

The density of the fibers on the first side of the surface of the first protruding part is preferably from 10 fibers / mm ² to 50 fibers / mm ² , and the density of the fibers on the second side of the surface is preferably from 20 fibers / mm ² to 100 fibers / mm ² . Preferably, the fiber density (r _11a ) on the first side of the surface of the first protruding part is preferably from 15 fibers / mm ² to 30 fibers / mm ² , and the fiber density (r _11b ) on the second side of the surface is preferably from 45 fibers / mm ² to 70 fibers / mm ² . As for the effect in which the ratio (r _11b / r _11a ) between the density of the fibers on the first side of the surface and the density of the fibers on the second side of the surface of the first protruding part is from 2 to 5, in addition to the flexibility and other properties described above, it is possible to obtain good fluid permeability due to increased fluid retraction force.

The technical conditions for measuring a nonwoven material according to an aspect will be described below.

Regarding the thickness of the sheet, the total thickness of the nonwoven fabric at low pressure (0.05 × 10 ³ Pa) is called the thickness of the sheet (T) (hereinafter T means the thickness at low pressure (0.05 × 10 ³ Pa)), and the local thickness of the unevenly curved sheet for difference is called the layer thickness (S) (see Fig. 2). The thickness of the sheet (T) can be appropriately adjusted depending on the application, and it is preferably from 0.5 mm to 10 mm, and more preferably from 1 mm to 5 mm, depending on the application as a top sheet for diapers, sanitary napkins and the like. . With this range, you can get a preferred feeling of cushioning. The thickness of the layer may vary in each part of the sheet, and it can be properly adjusted depending on the application. When used as a top sheet for diapers, sanitary napkins and the like, the layer thickness (S1) of the upper part of the first protruding part is preferably from 0.2 mm to 3.0 mm and more preferably 0.6 mm to 2.0 mm. As for the preferred range of layer thicknesses, the range of layer thicknesses (S2) of the upper portion of the second protruding part and the thickness range of the layer (S3) of the wall portion are as described above. The ratio of the layer thicknesses (S1), (S2) and (S3) is preferably the following: S1>S3> S2. Therefore, in the first protruding portion, the thickness of the fibrous layer is especially large on the surface of the skin, and good contact with the skin can be ensured. On the other hand, the thickness of the fibrous layer of the wall portion, the second protruding portion and the wall portion is small, however, the specific gravity is essentially the same as that of the first protruding portion, and thus, a high density non-woven material that is less prone to destruction and has good cushioning properties without loss of shape.

According to an aspect, the sheet thickness (T) is divided into three parts, the first protruding part 1, the second protruding part 2 and the wall part 3, and the proportion of each part is determined as described above, unless otherwise specified. Thus, these thickness values are determined arbitrarily depending on the sheet thickness (T) (P ₁ = P ₂ = P ₃ ). However, when the excess or curvature of the upper part of the first protruding part 1 and the second protruding part 2 is different, the relatively narrow part in the form of a line in the cross section is considered as the wall part and 3, and the areas that are folded from the part and go around can be considered in as the first protruding part 1 and the second protruding part 2 (see P ₁ , P ' ₂ and P' ₃ ). According to the latter definition, the thickness (P ′ ₂ ) of the second protruding part 2 in the non-woven fabric 10 according to the aspect is greater than the thickness (P ₁ ) of the first protruding part 1, and the non-woven material 10 has a shape that is offset in the direction of the thickness as a whole. In other words, according to an aspect, the radius of curvature of the upper part 11 of the first protruding part 1 is greater than the radius of curvature of the upper part 21 of the upper part 2 of the second protruding part 2.

The thickness at the middle of the length (t ₁ ) on the first side of the surface and the thickness at the middle of the length (t ₂ ) on the second side of the surface are also the same as above, and, as a rule, the line that bisects the thickness of the sheet (T) is considered as the midline (middle surface) m, and both thicknesses in the middle of the length (t ₁ , t ₂ ) are equal. However, when the excess or curvature radius of the upper part of the first protruding part 1 and the second protruding part 2 is different, the position m ′, taken as the center of the part in the form of a line in the cross section of the wall part and to be determined, can separate the thickness. According to the latter definition, in the nonwoven fabric according to the aspect, the thickness in the middle of the length t ₁ on the first side of the surface is less than the thickness in the middle of the length t ₂ on the second side of the surface.

The spacing n between the lines (see FIG. 5), which is formed by the first protruding part 1 and the second protruding part 2, can be appropriately adjusted depending on the application, and it is preferably from 1 mm to 15 mm and more preferably from 2 mm to 8 mm depending on the application as a top sheet for diapers, sanitary napkins and similar products.

The surface density of the nonwoven material according to the aspect is not limited and is preferably from 10 to 100 g / m ² and more preferably 20 to 50 g / m ² as the average value of the entire sheet.

As an example of a method of manufacturing a nonwoven material 10 according to an aspect, the embodiment described below is included. Before fusion, the fibrous web comes from the carding machine to the web forming apparatus so that a predetermined specific gravity is obtained. A device for forming a web, for example, includes a base that is irregular in shape and equipped with numerous ventilation holes, their drive unit, a device for blowing hot air flow almost vertically onto the surface of the base, and the like.

In the web forming apparatus, the aforementioned fibrous web is guided to the upper part of the base (not shown in the drawing) with numerous protrusions and breathability. After that, the hot air stream is blown into the fibrous web on the base at a temperature at which each fiber can be properly fused to form a fibrous web along the protrusions on the base and fused each fiber. As the shape of the protrusion of the base, a solid shape is used having a rounded triangular surface oriented in the transverse direction. In addition, the openings through which the hot air stream penetrates are equipped in place surrounded by two protrusions. The base structure, including the protrusions and holes, is not a structure in which numerous components are combined, but preferably a structure that is single and does not contain compounds is used. You can use various intervals and heights of the protrusions of the base.

The temperature of the hot air stream in this case is preferably from 100 to 180 ° C, and the air speed is preferably from 10 to 100 m / s, taking into account the usual fibrous materials used for products of this type. Taking into account continuous production, the aforementioned base includes a conveyor type or drum type, which is suitable for transmission. After blowing the hot air stream, it is possible to carry out the step of blowing air at normal or reduced temperature for the purpose of cooling and cleaning. A variant is used in which the molded non-woven material to be carried is wound onto a roll. In the nonwoven material according to the aspect, any direction for use can be determined as machine direction and lateral direction.

Examples of thermoplastic fibers may include polyolefins, such as polypropylene and polyethylene, polyesters, polyamides, such as nylon 6 and nylon 66, polyacrylonitriles and the like, or bicomponent fibers with a central core and sheath or adjacent fibers, consisting of two or more of these fibers, and the like. When a bicomponent fiber including a low-melting component and a high-melting component is used as a thermoplastic fiber, the temperature of the hot air stream being blown onto the fiber web is preferably equal to or higher than the melting temperature of the low-melting component, and lower than the melting temperature of the high-melting component component. The temperature of the hot air stream blown onto the fibrous web is preferably from the melting point of the low-melting component + (plus) 0 ° C to the melting point of the high-melting component - (minus) 10 ° C, and more preferably from the melting point of the low-melting component + (plus) 5 ° C to the melting temperature of the refractory component - (minus) 20 ° C. The fibrous web and nonwoven fabric include a thermoplastic fiber comprising preferably from 30 to 100 wt.% And more preferably from 40 to 80 wt.%. The fibrous web and nonwoven fabric may include a fiber that initially lacks hot-melt properties (for example, natural fiber such as cotton and cellulose, viscose and acetate fiber, etc.).

The following is a description of a second structural feature (second aspect) of the nonwoven fabric 10 in this embodiment. The characteristic structure as the second aspect of the nonwoven material 10 is not a structure that independently and exclusively relates to the structural features of the first aspect, and if this does not lead to contradictions, the structural features can coexist with each other and can be combined appropriately.

Next, excretion retention properties will be described as a feature of the nonwoven fabric 10 according to the second embodiment. The nonwoven fabric according to this aspect is particularly effective when used as a topsheet for disposable diapers and has excellent retention and diffusion preventing properties of a loose stool having high viscosity or in suspension. This depends on the holding properties, manifested, in particular, in the form of a function of the internal spaces 2k of the second protruding parts, as described above, and in this case depends on the function according to which the second protruding parts are less prone to deformation upon application of pressure, and, thus therefore, loose stools are less prone to flow into adjacent interior spaces, since the interior spaces 2k share the connecting parts (corrugated parts) 6, as described below, and they exist independently.

As a result, diffusion of loose stools is suppressed, and it is possible to prevent, for example, a situation in which loose stool flows out of the diaper. In addition, the first protruding parts that are flexibly transformed act as parts supported by the skin, and the elasticity of the wall part by its action retains independent internal spaces 2k having compression resistance. As a result, loose stools held up by the interior space 2k of the second protruding portion remain held up in a cup-shaped space, and excessive diffusion of the loose stool is suppressed even when, for example, the child moves and sits on the floor. In addition, the pressure applied to the nonwoven material according to this aspect is first distributed over the surface (pressure-limiting surface) due to deformation, where the contact points of the first protruding part on the skin extend along the surface shape, and then the upper surface of the cup-shaped structure part touches with the skin, which immediately further increases the pressure-limiting surface, and thus the shape is easily maintained; in addition, the non-woven fabric is soft and tender in contact, and the loose stools are less likely to adhere to the skin due to the supporting function of the first protruding part and the wall part. When worn, there is no stickiness, and skin diaper rash is preferably prevented. Effects that prevent diffusion of loose stools and loose stools become less prone to sticking to the skin are expressed by estimating the amount of loose stool adhering to the skin and the diffusion area of the loose stool, as described below.

Due to the aforementioned corrugated part (connecting part) 6, the first protruding parts are connected to each other, and the second protruding parts are separated from each other. In particular, as shown in FIG. 5, the first protruding parts are joined to each other by means of corrugated parts (connecting parts) 61-64, forming internal spaces 2k with an independent bowl-shaped structure. On the other hand, the second protruding parts are separated from each other by the corrugated parts (connecting parts) 61-64, forming continuous internal spaces 1k. As a result, the variable fluidity under pressure is improved, providing a good wearing feeling, and the blocking properties of subsequent excrement retention are excellent, and their diffusion can be effectively suppressed and prevented. Thus, when pressure is not applied, the interior spaces 2k that the connecting part (corrugated part) separates exist independently, and therefore the diffusion suppression effect is excellent in highlighting the stool. When pressure is applied, although the first protruding part is deformed, the corrugated part stops this deformation, and thus, the blocking properties of the subsequent excrement retention are excellent, the diffusion of which can be prevented more efficiently. In the present invention, when the inner space 1k of the first protruding part or the inner space 2k of the second protruding part is considered as a recess, the term “corrugated” “corrugated” means a continuous part of a hill-shaped protrusion between two recesses, and, as a rule, it has a surface, oriented in almost the same direction as the direction of the surface of the sheet of nonwoven material.

In the nonwoven material according to the aspect, the density of the fibers in the first protruding part is lower than the density of the fibers in the second protruding part. As a result, the first protruding portion is properly destroyed by compression, there is no sensation of itching on the skin, and a soft touch to the skin can be provided. On the other hand, the second protruding part is less prone to destruction, and has excellent shape retention and subsequent excrement retention properties, good cushioning properties without loss of shape, and excellent diffusion prevention properties of the detained substances. The density of the fibers is estimated by measuring the number of fibers per 1 mm ² . Thus, when the number of fibers per 1 mm ² increases, the fiber density becomes high.

For the above reason, the density of the fibers in the first protruding portion is preferably from 30 fibers / mm ² to 130 fibers / mm ² and more preferably from 50 fibers / mm ² to 100 fibers / mm ² . For the above reason, the density of the fibers in the second protruding part is preferably from 250 fibers / mm ² to 500 fibers / mm ² and more preferably from 300 fibers / mm ² to 450 fibers / mm ² . In addition, the difference between the density of the fibers in the first protruding part and the density of the fibers in the second protruding part is preferably 150 fibers / mm ² or more.

According to an aspect, the thickness (T _p ) under pressure conditions of 3.5 × 10 ³ Pa is preferably from 20 to 70% and more preferably from 30 to 60% of the thickness (T) at low pressure (0.05 × 10 ³ Pa). When the thickness (T _p ) under pressure is equal to or less than the aforementioned upper limit of the thickness (T) at low pressure, flexible deformation occurs when the carriers move and sit down, and difficulties are unlikely to be felt, which is preferred. In addition, the nonwoven material does not completely collapse at the aforementioned lower limit or higher pressure, its bulk shape can be maintained, and thus, the excretion retention properties can be manifested sufficiently. Thus, according to an aspect, the nonwoven material is not completely destroyed even under pressure, and its bulk shape is maintained. Thus, its depreciation properties, excretion retention properties, and diffusion prevention properties, as described above, are manifested. A preferred range of sheet thicknesses (T) will be described below.

According to an aspect, as described above, the fibers of the wall portion have an orientation of the fibers along a direction connecting the first protruding part and the second protruding part. Thus, in the wall portion, the fibers are oriented in the thickness direction. In the present invention, the expression “fibers have an orientation in the thickness direction” means a state in which the fibers are oriented in the thickness direction, and in particular, means that the orientation angle is from 50 ° to 130 ° and the orientation stability is 1.05 or more when measured by the method described below.

According to an aspect, the fibers also have a radial orientation in which the fibers converge towards the upper part 21 of the second protruding part 2, as shown in FIG. 7. Thus, this shows that when describing the relationship with the aforementioned wall portion, the fibers are oriented so that they converge towards the upper part 21 of the second protruding part through the second protruding part 2 from the wall part 3 along the surface direction of the corresponding sheet. Accordingly, the sheet has elasticity, and the solid material is maintained under pressure due to the presence of the radial orientation of the fibers of the upper part 21 of the second protruding part. Thus, depreciation properties, excretion retention properties and diffusion preventing properties are manifested, as described above.

According to an aspect, the orientation of the fibers (q ₂₁ ) in the thickness direction in the upper part of the second protruding part is lower than the orientation of the fibers (q ₃ ) in the thickness direction of the wall part, and has a value almost equal to the corresponding value of conventional non-woven materials. As a consequence, the tensile strength in the machine direction and the transverse direction of the nonwoven sheet can be maintained at a high level, which can prevent tearing and stretching of the sheet during production. From this point of view, it is preferable that the orientation angle q ₃ is from 50 ° to 130 °, and the orientation stability is 1.05 or more. Preferably, the orientation angle q ₂₁ is 0 ° or more and less than 50 ° or more than 130 ° and 180 ° or less, and it is preferable that the orientation stability is less than 1.05.

According to an aspect, the number of fibers (u ₁ ) of the first protruding part and the number of fibers (u ₂ ) of the second protruding part are essentially the same. Unless otherwise specified, the method for measuring the amount of fibers in the present invention is the method described below. As a result of this, curvature is less prone to occur during deformation under the influence of pressure and the like, and shape recovery easily occurs when pressure disappears, which is preferred. In addition, since the number of fibers in the nonwoven material is almost the same, the values of physical properties, such as the strength of the nonwoven material, are stable, and changes in sensations due to irregularities and tearing of the fibers are less prone to occur, which is preferred.

In addition, a substantial equality in the number of fibers can be a degree to which a functionally significant difference does not occur. In addition, the number of fibers has the same definition as surface density or specific gravity, and unless otherwise specified, it is measured using the method of measuring the number of fibers presented in the first aspect.

In a nonwoven fabric according to an aspect, the number of fiber fusion points (n ₁ ) in the first protruding part is lower than the number of fiber fusion points (n ₂ ) in the second protruding part. As a result, the first protruding portion is properly destroyed by compression, does not create an itching sensation on the skin, and may exhibit a soft touch to the skin. On the other hand, the second protruding part is less prone to fracture, has excellent shape retention properties after excrement retention, good cushioning properties, and excellent diffusion-preventing properties of retained substances without loss of shape. The number of fiber fusion points is determined by counting the number of fiber fusion points per 1 mm ² . For the above reason, the number of fiber fusion points n ₁ is preferably from 30 dots / mm ² to 130 dots / mm ² and more preferably 50 dots / mm ² to 100 dots / mm ² . For the aforementioned reason, the number of fiber fusion points n ₂ is preferably from 250 dots / mm ² to 500 dots / mm ² and more preferably from 300 dots / mm ² to 450 dots / mm ² .

The technical conditions for measuring a nonwoven material according to an aspect will be described below.

Regarding the thickness of the sheet, the total thickness of the nonwoven fabric at low pressure (0.05 × 10 ³ Pa) is called the thickness of the sheet (T) (hereinafter T means the thickness at low pressure (0.05 × 10 ³ Pa)), and the local thickness of the unevenly curved sheet for difference is called the layer thickness (S) (see Fig. 2). The thickness of the sheet (T) can be appropriately adjusted depending on the application, and it is preferably from 2 mm to 6 mm and more preferably from 3 mm to 5 mm, depending on the application as a top sheet for diapers, sanitary napkins and the like. With this range, you can get a preferred feeling of cushioning. The thickness of the layer may vary in each part of the sheet, and it can be properly adjusted depending on the application. When used as a top sheet for diapers, sanitary napkins and the like, the layer thickness (S1) of the upper part of the first protruding part is preferably from 0.2 mm to 3.0 mm and more preferably 0.6 mm to 2.0 mm. As for the preferred range of layer thickness, the layer thickness range (S2) of the upper part of the second protruding part and the wall thickness range of the layer (S3) of the wall part are as described above. The ratio of the layer thicknesses (S1), (S2) and (S3) is preferably the following: S1>S3> S2. Therefore, in the first protruding portion, the thickness of the fibrous layer is especially large on the surface of the skin, and good contact with the skin can be ensured. On the other hand, the thickness of the fibrous layer of the wall part, the second protruding part and the wall part is small, however, the specific gravity is almost the same as that of the first protruding part, and thus, a non-woven material having a high density can be obtained which is less inclined to destruction and has good cushioning properties without loss of shape.

According to an aspect, the sheet thickness (T) is divided into three parts, the first protruding part 1, the second protruding part 2 and the wall part 3, and the proportion of each part is determined as described above, unless otherwise specified. Thus, these thickness values are determined arbitrarily depending on the sheet thickness (T) (P ₁ = P ₂ = P ₃ ). However, when the excess or curvature of the upper part of the first protruding part 1 and the second protruding part 2 is different, the relatively narrow part in the form of a line in the cross section is considered as the wall part 3, and the areas that are folded away from the part and go around can be considered as the first protruding part 1 and the second protruding part 2 (see P ₁ , P ' ₂ and P' ₃ ). According to the latter definition, the thickness (P ′ ₂ ) of the second protruding part 2 in the non-woven fabric 10 according to the aspect is greater than the thickness (P ₁ ) of the first protruding part 1, and the non-woven material 10 has a shape that is offset in the direction of the thickness as a whole. In other words, according to an aspect, the radius of curvature of the upper part 11 of the first protruding part 1 is greater than the radius of curvature of the upper part 21 of the upper part 2 of the second protruding part 2.

The thickness at the middle of the length (t ₁ ) on the first side of the surface and the thickness at the middle of the length (t ₂ ) on the second side of the surface are also the same as above, and, as a rule, the line that bisects the thickness of the sheet (T) is considered as the midline (middle surface) m, and both thicknesses in the middle of the length (t ₁ , t ₂ ) are equal. However, when the excess or curvature radius of the upper part of the first protruding part 1 and the second protruding part 2 is different, the position m ′, taken as the center of the part in the form of a line in the cross section of the wall part and to be determined, can separate the thickness. According to the latter definition, in the nonwoven fabric according to the aspect, the thickness in the middle of the length t ₁ on the first side of the surface is less than the thickness in the middle of the length t ₂ on the second side of the surface.

The spacing n between the lines (see FIG. 5), which is formed by the first protruding part 1 and the second protruding part 2, can be appropriately adjusted depending on the application, and it is preferably from 1 mm to 15 mm and more preferably from 3 mm to 10 mm depending on the application as a top sheet for diapers, sanitary napkins and similar products.

The surface density of the nonwoven material according to the aspect is not limited and is preferably from 15 to 50 g / m ² and more preferably 20 to 40 g / m ² as the average value of the entire sheet.

As an example of a method of manufacturing a nonwoven material 10 according to an aspect, the embodiment described below is included. Before fusion, the fibrous web comes from the carding machine to the web forming apparatus so that a predetermined specific gravity is obtained. The device for forming the web, for example, includes a base that has an uneven shape and is equipped with numerous ventilation holes, their drive unit, a device for blowing hot air flow almost vertically onto the surface of the base.

In the web forming apparatus, hot air flow enters to fix the aforementioned fibrous web on an upper base (not shown in the drawing) with numerous projections 9 (web in FIG. 2) and breathability. As the shape of the protrusion of the base, a solid shape is used having a rounded triangular surface oriented in the transverse direction. In addition, the openings through which the hot air stream penetrates are equipped in place surrounded by two protrusions. The base structure, including the protrusions and holes, is not a structure in which numerous components are combined, but preferably a structure that is single and does not contain compounds is used. You can use a variety of intervals and heights of the protrusions of the base.

After that, the hot air stream h (see Fig. 2) is blown into the fibrous web onto the base at a temperature at which each fiber can be properly fused to form a fibrous web along the protrusions 9 on the base and fused each fiber. The temperature of the hot air stream in this case is preferably 0-70 ° C higher, preferably 5-50 ° C, the melting temperature of the thermoplastic fiber constituting the fibrous web. After the hot air stream, it is possible to carry out the stage of blowing air at normal or reduced temperature for the purpose of cooling and cleaning. Examples of thermoplastic fibers may include polyolefins, such as polypropylene and polyethylene, polyesters, polyamides, such as nylon 6 and nylon 66, polyacrylonitriles and the like, or bicomponent fibers with a central core and sheath or adjacent fibers consisting of two or more of these fibers, and the like. When a bicomponent fiber including a low-melting component and a high-melting component is used as a thermoplastic fiber, the temperature of the hot air stream being blown onto the fiber web is preferably equal to or higher than the melting temperature of the low-melting component and less than the melting temperature of the high-melting component. The temperature of the hot air stream blown onto the fibrous web is preferably from the melting point of the low-melting component + (plus) 0 ° C to the melting point of the high-melting component - (minus) 10 ° C, and more preferably from the melting point of the low-melting component + (plus) 5 ° C to the melting temperature of the refractory component - (minus) 20 ° C. The fibrous web and nonwoven fabric include a thermoplastic fiber, comprising preferably from 30 to 100 wt.% And more preferably from 40 to 80 wt.%. The fibrous web and nonwoven fabric may include a fiber that initially lacks hot-melt properties (for example, natural fiber such as cotton and cellulose, viscose and acetate fiber, etc.).

When forming a fibrous web, the speed of the hot air stream from the point of view of forming ability and sensation is preferably from 20 to 130 m / s and more preferably from 30 to 100 m / s. When the air flow rate is equal to or exceeds the lower limit, the volumetric effect becomes sufficient, and the effects of depreciation and excretion retention properties are manifested sufficiently, which is preferred. When the air flow rate is equal to or less than the upper limit, the sheet does not contain holes and good compression resistance is maintained. Thus, the effects of depreciation and excretion retention properties can be manifested sufficiently, which is preferred.

Taking into account continuous production, the aforementioned base includes a conveyor type or drum type, which is suitable for transmission. After using the hot air stream, an air purge step may be carried out for the purpose of cooling and cleaning.

The mode in which the molded non-woven material to be wound onto the roll is turned on. In the nonwoven fabric according to the aspect, any direction can be defined as the machine direction and the transverse direction, and it is preferable that the longitudinal direction be the machine direction in the model circuit illustrated in FIG. 5.

The following is a description of a third structural feature (third aspect) of the nonwoven material 10 in this embodiment. The characteristic structure as the third aspect of the nonwoven fabric 10 is not a structure that independently and exclusively relates to the structural features of the first aspect and the second aspect, and if this does not lead to contradictions, the structural distinguishing features can coexist with each other and can be combined appropriately .

In the nonwoven fabric 10, the composition will be described as a characteristic structure and a third aspect in which the density of the fibers (r _11a ) on the first side of the surface z _{1 of the} upper part 11 of the first protruding part 1 is lower than the density of the fibers (r _11b ) on the second side of its surface z ₂ (r _11a <r _11b ) and the corresponding function. Unless otherwise specified, in the present invention, the method for measuring fiber density is the method illustrated in the example. For fiber density, the designation of each part is represented as a subscript, and the value with the letter “r” represents the density of the fibers. In addition, the orientation of the fibers (q), etc. also expressed according to the above rule.

According to an aspect as described above, the density of the fibers (r _11a ) on the first side of the surface z ₁ and the density of the fibers (r _11b ) on the second side of the surface z _{2 of the} first protruding part 1 are related by the ratio r _11a <r _11b , and thus, In this part, there are simultaneously the properties of flexibility and shape retention. Both of these functions, as a rule, with a low probability exist in such a nonwoven material, however, due to the creation of a certain high and low density of fibers, as described above, a part with structural deformation due to compression from the outside arises, and in this part a structure that retains this part, and the above functions are provided. For example, in the upper part 11 of the first protruding part of the fiber on the second side of the surface are "dense", and thus, the relatively rigid part is included in the work as a bridge support. The first side of the surface is soft, generally non-rigid and retains sufficient flexibility, and thus a soft texture is felt when touched. In addition, the behavior under pressure is different on the first side of the surface, where the density of the fiber structure is lower, as described above, and on the second side of the surface, which is more dense. The second side of the surface, for which it is believed that the fibers are tightly laid along the shape of the first protruding part, has cushioning properties due to structural deformation of the entire first protruding part and contributes to the properties of rapid restoration of the structure. On the other hand, the first side of the surface, for which it is believed that the fibers form a mesh structure extending (ascending) from the curved surface of the first protruding part, has cushioning properties due to deformation of the affected part and its surroundings and promotes flexibility due to slow restoration of the structure. In addition, in the upper part 11 of the first protruding part, the density of fibers on the second side of the surface is higher than the density of fibers on the first side of the surface, and thus the body fluids quickly move to the second side of the surface, and the skin coming into contact on the first side surface is kept dry.

As for the fiber density in the first protruding part, r _11a is preferably from 15 fibers / mm ² to 120 fibers / mm ² and more preferably from 20 fibers / mm ² to 80 fibers / mm ² from the point of view of a sufficient manifestation of the above effect. The r _11b value is preferably from 20 fibers / mm ² to 150 fibers / mm ² and more preferably from 30 fibers / mm ² to 120 fibers / mm ² . The ratio between r _11a and r _{11b is} not limited, and r _11a / r _11b is preferably from 1.2 or more and 5 or less, and particularly preferably 1.5 or more and 4 or less.

According to an aspect, the absolute value (| r _11a -r _11b |) of the fiber density difference between both sides of the surface of the upper protruding part is higher than the absolute value (| r _21a -r _21b |) of the fiber density difference between both sides of the surface of the upper part of the second protruding part. At the same time, the density of the fibers (r _21a ) on the first side of the surface and the density of the fibers (r _21b ) on the second side of the surface of the upper part of the second protruding part are almost the same.

Thus, the ratio is as follows: r _21a = r _21b > r _11b > r _11a . As a consequence, body fluids released on the first side of the surface of the first protruding part move to the second side of the surface of the first protruding part, and the fluids further move to the second protruding part, and thus not only the skin coming into contact on the first side of the surface is kept in a drier state, but also the reverse movement of the fluid is less prone to occur even when a load is applied when the user sits down.

From the point of view of a sufficient manifestation of the above effect, the fiber densities (r _21a and r _21b ) in the second protruding part are preferably from 30 fibers / mm ² to 500 fibers / mm ² and more preferably from 50 fibers / mm ² to 200 fibers / mm ² . In addition, the fiber densities r _21a and r _21b are almost the same, and this may represent the extent to which no functionally significant difference occurs, and this means, for example, that | r _21a -r _21b | is 10 fibers / mm ² or less.

According to an aspect, the fibers also have a radial orientation in which the fibers converge towards the upper part 21 of the second protruding part 2, as shown in FIG. 7. Thus, this shows that in the description of the relationship with the aforementioned wall part, the fibers are oriented so that they converge towards the upper part 21 of the second protruding part through the second protruding part 2 from the wall part 3 along the surface direction of the corresponding sheet. Accordingly, due to the presence of the radial orientation of the fibers of the upper part 21 of the second protruding part, the load resistance increases in the direction of the thickness of the protruding part, the damping properties and shape retention properties are improved, and the reverse movement of the fluid is less prone to occur even if the load is applied when the user sits down. In addition, a function is manifested in which the properties of recovery after unloading are improved.

The orientation of the fibers (q ₁₁ ) of the upper part 11 of the first protruding part and the orientation of the fibers (q ₂₁ ) of the upper part of the second protruding part is different. Unless otherwise specified, a method for measuring fiber orientation in the present invention is the method illustrated in the example. Here, the value of the orientation of the fibers is a concept that makes up the angle of orientation and stability of the orientation of the fibers. The fiber orientation angle is a concept showing in which direction a plurality of fibers having a different orientation are oriented as a whole, and the shape of the fiber population is expressed in numbers. Fiber orientation stability is a concept showing the number of fibers exhibiting an orientation angle. When the orientation stability is less than 1.1, the fibers have a weak orientation, and when the orientation stability is 1.1 or more, it can be said that the fibers have a strong orientation. According to an aspect, however, the orientation of the fibers varies depending on their position. Thus, during a change in position having an orientation angle to a position having a different orientation angle (during a change in position in which the fibers have high orientation stability to a position showing high stability of a different orientation), this aspect provides for various states, such as a state of low orientation stability and a state of high orientation stability, by changing orientation. Therefore, even if the orientation stability of the fibers is low, it is preferable that the orientation angle of the fibers is changed from a position having one strong orientation angle to a position having an orientation angle in the other direction, and it is more preferable that the orientation stability is high. As an example of orientation stability according to an aspect, the upper part 11 of the first protruding part preferably has an orientation angle of 50 to 130 ° and more preferably 60 to 120 ° with respect to the curved surface structure of the first protruding part 1, and orientation stability (X ₁₁ ) is 1.05 or more and more preferably 1.15 or more. On the other hand, in the second protruding part, the fibers are oriented so that they converge towards the upper part 21, as described above, and thus, the orientation angle of the fibers is an orientation angle from 0 to 40 ° or from 140 ° to 180 ° with respect to the curved surface structure of the second protruding part 2, and more preferably the orientation angle is from 0 to 30 ° or 150 ° to 180 °, and the orientation stability (X ₂₁ ) of the upper part is 1.05 or more and more preferably 1.15 or more. Due to the different orientation of the fibers of the upper part, different compression behavior occurs, and in the upper part of the first protruding part, depreciation properties appear due to deformation of the affected part and its surroundings. Structural deformation, such as a deviation of the entire protruding part, easily occurs in the second protruding part, however, the second protruding part has a fiber structure that converges toward the aforementioned upper part, and thus an action in which suppressing the deformation and easy recovery after deformation is manifested are ensured due to accompanying deformation in different directions for different positions by deformation in a certain direction when viewed from the upper surface .

In addition, unless otherwise specified, in the present invention, the direction along the sheet thickness direction represents an orientation angle of 90 °, and this corresponds to the Z direction shown in FIG. 2.

As for the fiber orientation upper part 21 of the second projecting portion in the nonwoven fabric 10 according to an aspect, the fiber orientation (q _21a) of the first side surface and the fiber orientation (q _21b) of the second side surfaces are substantially identical. As a consequence, the second protruding part has a uniform structure, and thus, the shape retention properties and shape restoration properties are excellent, as described above, and the body fluids move easily due to the orientation towards the upper part as a whole. In the present description, a practical alignment of orientation means that the difference in angles is 20 ° or less and more preferably 10 ° or less, and the difference in stability of the orientation is 0.5 or less and more preferably 0.3 or less, and when the orientation angle is more than 90 °, it is recalculated into an angle from 0 to 90 ° (ascent angle from 180 °). The orientation stability interval between q _21a and q _{21b is} not limited, and it is preferably 1.05 or more and more preferably 1.15 or more, taking into account the shape retention properties and the shape recovery properties of the second protruding parts.

According to an aspect, the number of fibers (u ₁ ) of the first protruding part and the number of fibers (u ₂ ) of the second protruding part are almost the same. Unless otherwise specified, the method for measuring the amount of fibers in the present invention is the method described below. As a consequence, curvature is less prone to occur during deformation under the influence of pressure and the like, and shape recovery easily occurs when pressure is relieved, which is preferred. In addition, since the number of fibers in the nonwoven material is almost the same, the values of physical properties, such as the strength of the nonwoven material, are stable, and changes in sensations due to irregularities and tearing of the fibers are less prone to occur, which is preferred.

In addition, a substantial equality in the number of fibers can be a degree to which a functionally significant difference does not occur. In addition, the number of fibers has the same definition as surface density or specific gravity, and unless otherwise specified, it is measured using the method of measuring the number of fibers presented in the first aspect.

As described below, the thickness of the first protruding part is greater than the thickness of the second protruding part, and thus, a difference in the degree of sparseness of the fibers can occur. Thus, a density gradient of the fibers occurs between the two parts, and the body fluids easily move into the absorbent element, which is preferred.

The technical conditions for measuring the nonwoven material according to this embodiment will be described below.

Regarding the thickness of the sheet, the total thickness of the nonwoven fabric at low pressure (0.05 × 10 ³ Pa) is called the thickness of the sheet (T) (hereinafter T means the thickness at low pressure (0.05 × 10 ³ Pa)), and the local thickness of the unevenly curved sheet for difference is called the layer thickness (S) (see Fig. 2). The thickness of the sheet (T) can be appropriately adjusted depending on the application, and it is preferably from 1 mm to 7 mm and more preferably from 1.5 mm to 5 mm, depending on the application as a top sheet for diapers, sanitary napkins and the like. . If this interval is observed, a preferred feeling of cushioning can be obtained. The thickness of the layer may vary in each part of the sheet, and it can be properly adjusted depending on the application. When used as a top sheet for diapers, sanitary napkins and the like, the layer thickness (S1) of the upper part of the first protruding part is preferably from 0.1 mm to 3 mm and more preferably 0.4 mm to 2 mm. As for the preferred range of layer thickness, the layer thickness range (S2) of the upper part of the second protruding part and the wall thickness range of the layer (S3) of the wall part are as described above. The ratio of the layer thicknesses (S1), (S2) and (S3) is preferably: S1>S3> S2. As a consequence, in the first protruding part, the degree of sparseness of the fibers is especially large on the surface of the skin (sparse), and good contact with the skin can be ensured. On the other hand, the degree of sparseness of the fibers in the wall part, the second protruding part and in the wall part is small (dense). A non-woven material having a high density can be obtained which is less prone to fracture and has good cushioning properties without loss of shape and having an excellent rate of absorption of body fluids.

According to an aspect, the sheet thickness (T) is divided into three parts, the first protruding part 1, the second protruding part 2 and the wall part 3, and the proportion of each part is determined as described above, unless otherwise specified. Thus, these thickness values are determined arbitrarily depending on the sheet thickness (T) (P ₁ = P ₂ = P ₃ ). However, when the excess or curvature of the upper part of the first protruding part 1 and the second protruding part 2 is different, the relatively narrow part in the form of a line in the cross section is considered as the wall part 3, and the areas that are folded away from the part and go around can be considered as the first protruding part 1 and the second protruding part 2 (see P ₁ , P ' ₂ and P' ₃ ). According to the latter definition, the thickness (P ′ ₂ ) of the second protruding part 2 in the non-woven fabric 10 according to the aspect is greater than the thickness (P ₁ ) of the first protruding part 1, and the non-woven material 10 has a shape that is offset in the direction of the thickness as a whole. In other words, according to an aspect, the radius of curvature of the upper part 11 of the first protruding part 1 is greater than the radius of curvature of the upper part 21 of the upper part 2 of the second protruding part 2.

The thickness at the middle of the length (t ₁ ) on the first side of the surface and the thickness at the middle of the length (t ₂ ) on the second side of the surface are also the same as above, and, as a rule, the line that bisects the thickness of the sheet (T) is considered as the midline (middle surface) m, and both thicknesses in the middle of the length (t ₁ , t ₂ ) are equal. However, when the excess or curvature radius of the upper part of the first protruding part 1 and the second protruding part 2 is different, the position m ′, taken as the center of the part in the form of a line in the cross section of the wall part and to be determined, can separate the thickness. According to the latter definition, in the nonwoven fabric according to the aspect, the thickness in the middle of the length t ₁ on the first side of the surface is less than the thickness in the middle of the length t ₂ on the second side of the surface.

The spacing n between the lines (see FIG. 5), which is formed by the first protruding part 1 and the second protruding part 2, can be properly adjusted depending on the application, and it is preferably from 1 mm to 10 mm and more preferably from 2 mm to 5 mm depending on the application as a top sheet for diapers, sanitary napkins and similar products.

The surface density of the nonwoven material according to the aspect is not limited and is preferably from 15 to 50 g / m ² and more preferably from 20 to 40 g / m ² as the average value of the entire sheet.

As an example of a method of manufacturing a nonwoven material 10 according to an aspect, the mode described below is turned on. Before fusion, the fibrous web comes from the carding machine to the web forming apparatus so that a predetermined specific gravity is obtained. The device for forming the web, for example, includes a base that has an uneven shape and is equipped with numerous ventilation holes, their drive unit, a device for blowing hot air flow almost vertically onto the surface of the base.

In the web forming apparatus, first, hot air flow enters to fix the aforementioned fibrous web on an upper base (not shown in the drawing) with numerous protrusions 9 (web in FIG. 2) and breathability. As the shape of the protrusion of the base, a solid shape is used having a rounded triangular surface oriented in the transverse direction. In addition, the openings through which the hot air stream penetrates are equipped in place surrounded by two protrusions. The base structure, including the protrusions and holes, is not a structure in which numerous components are combined, but preferably a structure that is single and does not contain compounds is used. You can use a variety of intervals and heights of the protrusions of the base.

The temperature of the hot air stream in this case is preferably lower by 0-70 ° C, more preferably 5-50 ° C, than the melting temperature of the thermoplastic fiber constituting the fibrous web, taking into account the usual fibrous materials used for products of this type. After blowing the hot air stream, it is possible to carry out the step of blowing air at normal or reduced temperature for the purpose of cooling and cleaning. After that, the hot air stream h (see Fig. 2) is blown into the fibrous web onto the base at a temperature at which each fiber can be properly fused to form a fibrous web along the protrusions 9 on the base and fused each fiber. The temperature of the hot air stream in this case is preferably 0-70 ° C, more preferably 5-50 ° C, than the melting temperature of the thermoplastic fiber constituting the fibrous web, taking into account the usual fibrous materials used for products of this type. Examples of thermoplastic fibers may include polyolefins such as polypropylene and polyethylene, polyesters, polyamides such as nylon 6 and nylon 66, polyacrylonitriles and the like, or bicomponent fibers with a central core and sheath or adjacent fibers, consisting of two or more of these fibers, etc. When a bicomponent fiber including a low-melting component and a high-melting component is used as a thermoplastic fiber, the temperature of the hot air stream being blown onto the fiber web is preferably equal to or higher than the melting temperature of the low-melting component and less than the melting temperature of the high-melting component. The temperature of the hot air stream blown onto the fibrous web is preferably from the melting point of the low-melting component + (plus) 0 ° C to the melting point of the high-melting component - (minus) 10 ° C, and more preferably from the melting point of the low-melting component + (plus) 5 ° C to the melting temperature of the refractory component - (minus) 20 ° C. The fibrous web and nonwoven fabric include a thermoplastic fiber, comprising preferably from 30 to 100 wt.% And more preferably from 40 to 80 wt.%. The fibrous web and nonwoven fabric may include a fiber that does not initially have hot-melt properties (for example, natural fiber such as cotton and cellulose, viscose and acetate fiber, etc.). After the hot air stream, an air purging step may be carried out for the purpose of cooling and cleaning.

When forming a fibrous web, the speed of the hot air flow from the point of view of forming ability and sensation is preferably from 20 to 150 m / s and more preferably from 30 to 100 m / s. When the air flow rate is equal to or exceeds the lower limit, the volumetric effect becomes sufficient, and the effects of depreciation and excretion retention properties are manifested sufficiently, which is preferred. In addition, predetermined ranges of fiber density and orientation are provided, and thus, the rate of absorption of body fluids is increased, and the amount of backward flowing fluid is reduced, which is preferred. When the air flow rate is equal to or less than the upper limit, the sheet does not contain holes and good compression resistance is maintained. Thus, the effects of depreciation and excretion retention properties can be manifested sufficiently, which is preferred. Taking into account the continuous production, the conveyor type or the drum type, which is suitable for transfer, is used as the aforementioned base, and a variant is used in which the molded non-woven material to be carried is wound onto a roll. In the nonwoven fabric according to the aspect, any direction can be defined as the machine direction and the transverse direction, and it is preferable that the longitudinal direction be the machine direction in the model circuit illustrated in FIG. 5.

The following is a description of a fourth structural feature (fourth aspect) of the nonwoven material 10 in this embodiment. The characteristic structure as the fourth aspect of the nonwoven material 10 is not a structure that independently and exclusively relates to the structural features of the first aspect, the second aspect and the third aspect, and if this does not lead to contradictions, the structural features can coexist with each other, and their can be combined appropriately.

As for the characteristic parts of the nonwoven material 10 according to the fourth embodiment, in the case where it is believed that the contacting flat surfaces 71 and 72 (see FIG. 8) simultaneously come into contact with a plurality of first protruding parts 1 and a plurality of second protruding parts 2 in nonwoven material 10, mesh spaces formed on both respective sides will be described, wherein these spaces extend in the direction of the surface between the contacting flat surfaces and the nonwoven material. FIG. 9 represents the shape in which the first protruding parts 1 and the second protruding parts extend and orient themselves in a first direction (x) and a second direction (y) on the surface as a model (the x direction and the y direction include directions represented by dash-dotted lines and directions in which they move in parallel). Each of the first protruding parts 1 and the second protruding parts 2 (broken lines), which are indicated by circles, schematically represents a position on a horizontal projection, and their centers are almost identical to the vertices of the upper parts. As shown in the drawing, in the nonwoven fabric 10 according to an aspect, the aforementioned mesh spaces V ₁ and V ₂ are formed on the first surface side and the second surface side of the nonwoven fabric, respectively. Thus, on the first side of the surface, the outer region bounded by the solid line of the circle of the first protruding part 1 is considered as net space (net space on the first side of the surface) V ₁ . On the other hand, on the second side of the surface, the outer region bounded by the broken line of the circle of the second protruding part 2 is considered as net space (net space on the second side of the surface) V ₂ . FIG. 10 is a model drawing. When, when a flat surface comes into contact, it is assumed that this surface consists of a rigid material that is not deformed, circles bounded by solid lines and circles bounded by broken lines can be considered as contact surfaces on which the first protruding parts and second protruding parts are destroyed, and these contact surfaces are formed when pressed against a surface consisting of rigid material.

Next will be presented the functions due to the characteristic structure of the nonwoven material according to the above aspect.

Breathability

In a nonwoven fabric according to an aspect, mesh spaces exist both on the first side of the surface and on the second side of the surface, and thus the moisture released by the carriers diffuses and can also efficiently diffuse the vapor released from the absorbent element.

Absorption capacity (fluid diffusion properties, fluid permeability)

In a nonwoven fabric according to an aspect, mesh spaces exist simultaneously on the first side of the surface and on the second side of the surface, and thus, when the fluid is absorbed, the fluid quickly diffuses into the mesh spaces, and the contact of the fluid with the skin is limited. Suitable spaces also exist in the fibrous structure of the nonwoven material, and the penetration of the fluid towards the absorbent element can also be suitably carried out, as well as the diffusion of the fluid. Furthermore, when the fluid flows out of the absorbent element due to exceeding the absorption limit and the like, the fluid diffuses accordingly into other absorbent parts retaining the absorbent capacity through the mesh spaces.

The compressive hardness (LC) required to maintain appropriate softness and absorption capacity is preferably from 0.01 to 0.35, more preferably from 0.05 to 0.3, and even more preferably from 0.1 to 0.25. The nonwoven material according to the aspect has a compressive hardness (LC) in the above range, and thus, the material can contain suitable free spaces, and high absorption capacity can be provided while maintaining flexibility.

FIG. 10 is an explanatory view schematically illustrating a deformation state of a nonwoven fabric pressed against a predetermined pressure assuming contact of a flat surface consisting of a rigid material as described above (for example, a metal base and a pressure plate), or in practical use thereof. The field of view is the same as the cross section shown in FIG. 2, and it is just shown. In the non-woven fabric 10 according to the aspect, even in the case where the non-woven material is pressed against the surface at a pressure of 50 gf / cm ^{2 of an} undeformable pressing surface, it is preferable that the mesh spaces V ₁ and V ₂ between the pressing surface and the non-woven material are maintained. Such retention properties of mesh spaces can exist only on the first side of the surface or on the second side of the surface. Thus, this shows that even when appropriate pressure is applied, proper recovery from deformation occurs, and the nonwoven material exhibits good cushioning properties. A pressure of 50 gf / cm ² corresponds, for example, to the pressure that occurs when a child sits, in the case where the material is used for an active absorbent article. Unless otherwise specified, the pressure measurement in the present invention is carried out using the method presented in the example described below.

Furthermore, with regard to the nonwoven fabric 10 according to the aspect, in the case where the nonwoven fabric is pressed in the direction of the pressure surface of 0.5 gf / cm ² deformable pressing surface, the ratio (S _0,5 / Sa) between the contact area S _0,5 the pressing surface and the nonwoven material and the unitary total surface area Sa of the pressing surface (when there is a space with an area of 1 mm ² or more in the direction of the surface, this space is excluded) is from 0.1 to 0.4, preferably from 0.12 to 0.35 and particularly preferably from 0.15 to 0.3. In this range, the contact area S _{0.5 is} smaller than the unitary total area under compression, and this means that the mesh spaces V ₁ and V ₂ are retained even under the compression conditions shown in FIG. 10 (b), and also means that the nonwoven fabric provides an excellent sensation, such as softness or smoothness, when touched. The pressure of 0.5 gf / cm ² corresponds, for example, to the pressure in the state of contact of the nonwoven fabric and the skin when the user does not sit down, if the material is used for an active absorbent article.

The contact area ratio described above is preferably obtained simultaneously on the first side of the surface and the second side of the surface, but can be obtained on one side. Furthermore, as regards the relationship between the aforementioned unitary total area Sa and the contact area S _0.5 , as shown in FIG. 9, the unitary total area Sa may be any region in the horizontal projection of the nonwoven material, and preferably a region including a plurality of first protruding parts and second protruding parts in an equal amount. On the other hand, when the circles bounded by solid lines in the drawing are considered to be the contact parts of the first protruding parts and the pressing surface, the contact area S _{0.5 of the} first protruding parts in the aforementioned unit common area Sa is the sum of the areas of the shaded areas. This ratio represents the aforementioned contact area ratio (S _0.5 / Sa).

According to an aspect, when compressing the nonwoven material in the direction of the surface with a pressure of 50 gf / cm ^{2 of} non-deformable pressing surface, the ratio (S ₅₀ / Sa) between the contact area S _{50 of the} pressing surface and the non-woven material and the unitary total area of the pressing surface Sa is from 0.3 to 0 , 9, preferably from 0.4 to 0.85, and particularly preferably from 0.5 to 0.8.

In this range, the contact area S _{50 is} smaller than the unit total area under compression (see FIG. 10 (c)), and this means that even when pressure is applied, for example, even when the user is sitting down, the structure of the nonwoven material contains spaces, and absorption capacity and breathability remain. The contact area ratio, as described above, is preferably provided simultaneously on the first side of the surface and on the second side of the surface, but can exist only on one side. The method for determining the contact area ratio (S ₅₀ / Sa) is the same as in the case of the above contact area ratio (S _0.5 / Sa), except that the upper and lower surfaces are different.

Furthermore, in the nonwoven fabric 10 according to an aspect ratio (T ₅₀ / T _0.5) between the thickness T of the sheet ₅₀ of nonwoven material under compression in the direction of the pressure surface 50 gf / cm ² deformable pressing surface and the sheet thickness of _0.5 T at a compression pressure 0.5 gf / cm ² in the same manner as described above is preferably from 0.1 to 0.4 and more preferably from 0.15 to 0.35. When creating a non-woven material having elasticity in the direction of the thickness of the sheet, such a non-woven material has excellent cushioning properties and increases the absorption capacity with respect to rapidly dripping fluids, and also reduces the reverse movement of the fluid.

According to an aspect, the fibers also have a radial orientation in which the fibers converge towards the upper part 21 of the second protruding part 2, as shown in FIG. 7. Thus, this shows that when describing the relationship with the aforementioned wall part, the fibers are oriented so that they converge towards the upper part 21 of the second protruding part through the second protruding part 2 from the wall part 3 along the surface direction of the corresponding sheet. Accordingly, functions are manifested, such as uniform appearance, shape retention properties and high absorption capacity, due to the presence of the radial orientation of the fibers of the upper part 21 of the second protruding part.

The technical conditions for measuring the nonwoven material according to this embodiment will be described below.

In terms of sheet thickness, the total thickness of the nonwoven fabric 10 at low pressure is called the thickness of the sheet (T) (hereinafter, T means thickness at low pressure, and the local thickness of the unevenly curved sheet is called layer thickness (S) for distinguishing purposes (see FIG. 2). The thickness of the sheet (T) can be appropriately adjusted depending on the application, and it is preferably from 1.8 mm to 4.5 mm, and more preferably from 2.2 mm to 4.2 mm, depending on the application as the top sheet for diapers, sanitary pads and similar products.

With this range, you can get a preferred feeling of cushioning. The thickness of the layer may vary in each part of the sheet, and it can be properly adjusted depending on the application. When used as a top sheet for diapers, sanitary napkins and the like, the layer thickness (S1) of the upper part of the first protruding part is preferably from 0.1 mm to 1 mm, and more preferably 0.2 mm to 0.8 mm. As for the preferred layer thickness range, the layer thickness range (S2) of the upper portion of the second protruding part and the wall thickness range of the layer (S3) of the wall portion are as described above.

In the nonwoven fabric 10 according to this embodiment, the thickness of the layer S1 of the first protruding part 1, the thickness of the layer S2 of the second protruding part and the thickness of the layer S3 of the wall part are substantially the same. Here, the term “substantially the same” means that when observing each cross section, they have almost the same thickness. By manufacturing a nonwoven material having such a shape, it is preferable to obtain uniformity of appearance, stable absorption capacity and cushioning properties.

It is preferable that the thickness of the nonwoven material according to the aspect is practically unchanged upon transition from a dry state to a wet state. Thus, the thickness variation coefficient described below is preferably from 85 to 115%, and more preferably from 90 to 110%.

Coefficient of change in thickness (%) = thickness in the wet state (mm) / thickness in the dry state (mm) × 100 (numerical formula 1)

Dry thickness

The thickness of the sheet after aging for 24 hours at normal temperature (23 ° C) and relative humidity 50%.

Wet thickness

The leaf is incubated for 24 hours at normal temperature (23 ° C) and a relative humidity of 50%. Purified by ion exchange water is poured into a flat container, which is larger than the sheet, to a height of 10 mm. The sheet is placed in a container and removed from it after one hour. This sheet thickness is considered as wet thickness.

According to an aspect, the sheet thickness (T) is divided into three parts, the first protruding part 1, the second protruding part 2 and the wall part 3, and the proportion of each part is determined as described above, unless otherwise specified. Thus, these thickness values are determined arbitrarily depending on the sheet thickness (T) (P ₁ = P ₂ = P ₃ ). However, when the excess or curvature of the upper part of the first protruding part 1 and the second protruding part 2 is different, the relatively narrow part in the form of a line in the cross section is considered as the wall part 3, and the areas that are folded away from the part and go around can be considered as the first protruding part 1 and the second protruding part 2 (see P ₁ , P ' ₂ and P' ₃ ). According to the latter definition, the thickness (P ′ ₂ ) of the second protruding part 2 in the non-woven fabric 10 according to the aspect is greater than the thickness (P ₁ ) of the first protruding part 1, and the non-woven material 10 has a shape that is offset in the direction of the thickness as a whole. In other words, according to an aspect, the radius of curvature of the upper part 11 of the first protruding part 1 is larger than the radius of curvature of the upper part 21 of the second protruding part 2.

The thickness at the middle of the length (t ₁ ) on the first side of the surface and the thickness at the middle of the length (t ₂ ) on the second side of the surface are also the same as above, and usually a line that bisects the sheet thickness (T), considered as the midline (middle surface) m, and both thicknesses in the middle of the length (t ₁ , t ₂ ) are equal. However, when the excess or curvature radius of the upper part of the first protruding part 1 and the second protruding part 2 is different, the position m ′, taken as the center of the part in the form of a line in the cross section of the wall part and to be determined, can separate the thickness. According to the latter definition, in the nonwoven fabric according to the aspect, the thickness in the middle of the length t ₁ on the first side of the surface is less than the thickness in the middle of the length t ₂ on the second side of the surface.

The spacing n between the lines (see FIG. 5), which is formed by the first protruding part 1 and the second protruding part 2, can be properly adjusted depending on the application, and it is preferably from 1 mm to 12 mm and more preferably from 2.5 mm up to 6 mm depending on the application as a top sheet for diapers, sanitary napkins and similar products.

As an example of a method of manufacturing a nonwoven material 10 according to an aspect, the embodiment described below is included. Before fusion, the fibrous web comes from the carding machine to the web forming apparatus so that a predetermined specific gravity is obtained. A device for forming a web, for example, includes a base that is irregular in shape and equipped with numerous ventilation holes, their drive unit, a device for blowing hot air flow almost vertically onto the surface of the base, and the like.

In the web forming apparatus, first air at normal temperature (23 ° C) is supplied to fix the aforementioned fibrous web on an upper base (not shown in the drawing) with numerous projections 9 (see FIG. 2) and air permeability. After that, the hot air stream h (see Fig. 2) is blown into the fibrous web onto the base at a temperature at which each fiber can be properly fused to form a fibrous web along the protrusions 9 on the base and fused each fiber. As the shape of the protrusion of the base, a solid shape is used having a rounded triangular surface oriented in the transverse direction. In addition, the openings through which the hot air stream penetrates are equipped in place surrounded by two protrusions. The base structure, including the protrusions and holes, is not a structure in which numerous components are combined, but preferably a structure that is single and does not contain compounds is used. You can use a variety of intervals and heights of the protrusions of the base.

The temperature of the hot air stream in this case is preferably from 130 to 160 ° C, and the air speed is preferably from 20 to 80 m / s, taking into account the usual fibrous materials used for products of this type. Taking into account continuous production, the aforementioned base includes a conveyor type that is suitable for transmission. After the hot air stream, an air purging step may be carried out for the purpose of cooling and cleaning. A variant is used in which the molded non-woven material to be carried is wound onto a roll. In the nonwoven fabric according to the aspect, any direction can be defined as the machine direction and the transverse direction, and it is preferable that the longitudinal direction be the machine direction in the model circuit illustrated in FIG. 5.

Examples of thermoplastic fibers may include polyolefins such as polypropylene and polyethylene, polyesters, polyamides such as nylon 6 and nylon 66, polyacrylonitriles and the like, or bicomponent fibers with a central core and sheath or adjacent fibers, consisting of two or more of these fibers, etc. When a bicomponent fiber including a low-melting component and a high-melting component is used as a thermoplastic fiber, the temperature of the hot air stream being blown onto the fiber web is preferably equal to or higher than the melting temperature of the low-melting component and less than the melting temperature of the high-melting component. The temperature of the hot air stream blown onto the fibrous web is preferably from the melting point of the low-melting component + (plus) 0 ° C to the melting point of the high-melting component - (minus) 10 ° C, and more preferably from the melting point of the low-melting component + (plus) 5 ° C to the melting temperature of the refractory component - (minus) 20 ° C. The fibrous web and nonwoven fabric include a thermoplastic fiber, comprising preferably from 30 to 100 wt.% And more preferably from 40 to 80 wt.%. The fibrous web and nonwoven fabric may include a fiber that initially lacks hot-melt properties (for example, natural fiber such as cotton and cellulose, viscose and acetate fiber, etc.).

As described above, when there is a characteristic structure according to the fourth aspect described above, the nonwoven material 10 has good breathability, excellent cushioning and deformation properties, does not adhere and is gentle to the skin, and it can preferably be used as top sheets, medium sheets, etc. for wearable products. In particular, when a nonwoven material is used as a middle sheet, a high conformity to movements can be obtained due to excellent cushioning properties and certain bulk deformation properties.

The fibrous materials that can be used for the nonwoven material of the present invention are not limited in a particular way. In particular, they include the following fibers: polyolefin fibers, such as polyethylene (PE) fibers and polypropylene (PP) fibers; fibers made using a single thermoplastic polymer such as polyethylene terephthalate (PET) or polyamide; bicomponent fibers having a structure of the type such as a core core and sheath or two adjacent fibers; for example, it is preferable to use fibers with a structure such as a central core and sheath, in which the sheath component is polyethylene or low melting polypropylene, and typical examples of fibers with a structure such as a central core and sheath are fibers in which PET (central core) / PE is used (sheath), PP (central core) / PE (sheath) or PP (central core) / low-melting PP (sheath). More specifically, the aforementioned constituent fibers are preferably polyolefin fibers, such as polyethylene fibers, polypropylene fibers, polyethylene bicomponent fibers or polypropylene bicomponent fibers. Here, the bicomponent composition of the polyethylene bicomponent fiber is polyethylene terephthalate / polyethylene, and the bicomponent composition of the polypropylene bicomponent fiber is preferably polyethylene terephthalate / low-melting polypropylene, and more specific examples include PET (center core) / PE (sheath) and PET (center core) / low-melting PP (shell). In addition, for the manufacture of non-woven material, these fibers can be used individually, and two or more types of fibers can be used in combination.

FIG. 11 is a partial cross-sectional perspective view that schematically illustrates a disposable diaper that utilizes a top sheet 10 according to this embodiment. The diaper illustrated in the drawing is a tape type of disposable diaper for children, which is shown in the state of flat opening in a slightly bent form when viewed from the inside (the surface side in contact with the skin). Needless to say, the top sheets 20, 30 and 40 (aspect 2, 3 and 4) can be used for the disposable diaper 100 in the embodiment instead of the top sheet 10 (this embodiment).

The disposable diaper 100 in an embodiment comprises a fluid permeable top sheet (nonwoven fabric) 10 located on a skin contacting surface side, a fluid impervious bottom sheet 71 located on a non-skin contact surface side, and located between these two sheets absorbent element 73 (see Fig. 11). Non-woven materials 10 are used as the top sheet according to the aforementioned embodiments, and the first protruding side of the surface is used as the skin contact surface. In an embodiment, the absorbent member 73 is disposed between the bottom sheet 71 and the top sheet 10. The bottom sheet 71 in the open state has an hourglass-like configuration in which both side edges taper in the central part c in the longitudinal direction, and one sheet or multiple sheets can be used . In an embodiment, side sheets 75 are provided as preventing lateral flow of frill 72, whereby it becomes possible to effectively prevent lateral leakage of fluid, and the like. in the place of the child’s hip joint, which occurs due to movement, etc. In the diaper according to the embodiment, it is possible to further provide a functional structural part, sheet material, and the like. In FIG. 11, the location and boundaries of each component are not presented in a strict manner, and this structure is not limited provided that it is the usual form of diapers of this type.

The illustrated diaper according to this embodiment is of the belt type, and a fixing tape 76 is provided in the valve portion on the rear side r. The tape 76 is attached to the tape holding part (not shown in the drawing) provided on the valve part from the abdomen f, whereby the diaper can be worn and fixed. In this case, the central part c of the diaper is slightly bent inward, and the absorbent element 73 is located from the part of the thigh to the lower abdomen of the baby, as a result of which the excreted substance can be properly absorbed and retained using the absorbent element 73. When used in this form, good texture, cushioning and retention properties of excrement, which is definitely due to the use of nonwoven material 10 according to this embodiment as the top sheet. In particular, it is possible to provide excretion retention properties with extremely high efficiency, which cannot be obtained using a traditional top sheet having linear protrusions and a sheet having small holes. For example, a child’s skin can preferably be protected from diaper rash due to stool in case of diarrhea, loose stool, and the like.

The nonwoven fabric of the present invention can be used for a variety of applications, for example, it can preferably be used as a topsheet for absorbent articles, such as disposable diapers, sanitary napkins, daily pads, and urological pads described above. In addition, forms are also included that are used as cleaning sheets, sub-layers (second sheets) for absorbent articles, absorbent sheets for buttocks, filters, and the like. For them, when the nonwoven material has a characteristic structure according to the fourth aspect, the air permeability, the diffusion properties of the fluid, the deformation characteristics under pressure, and the like, which are due to the mesh structures on both sides of the sheet, are excellent, and thus, the nonwoven material preferably used as an interlayer between the top sheet and the absorbent element for diapers, sanitary napkins and the like, and additional forms are also included which use crawl like top sheets, frills, outer sheets and wings.

The present invention will now be described for the following embodiments related to the above embodiments.

1. Non-woven material containing a first protruding part extending to the first side of the surface in a horizontal projection of the non-woven material in the form of a sheet, and a second protruding part extending to the second side of the surface as the opposite side from the first surface, in which there are many first protruding parts and second protruding parts, alternately through the wall parts, are distributed in two directions - the first direction and the second direction, in the horizontal projection of the non-woven material in which the wall The second part has a fiber orientation along the direction connecting the first projecting portion and a second projecting portion, in virtually any point in the surface direction defined as the first direction and the second direction.

2. Non-woven material containing a first protruding part extending to the first side of the surface in a horizontal projection of the non-woven material in the form of a sheet, and a second protruding part extending to the second side of the surface as the opposite side from the first surface, in which there are many first protruding parts and second protruding parts, alternately through the wall parts, is distributed and continuous in two directions - the first direction and the second direction, in the horizontal projection of the nonwoven material, in the wall part forms an annular structure, where the fiber density (r ₁ ) of the first protruding part is lower than the fiber density (r ₂ ) of the second protruding part.

3. The nonwoven material according to claim 1 or 2, in which the first protruding part and the second protruding part do not occupy the same position both in the horizontal projection and in the side projection, that is, both parts are arranged alternately without overlapping.

4. Non-woven material according to any one of paragraphs. 1-3, in which the protruding shape of the first protruding portion is a hemispherical shape, and the protruding shape of the second protruding portion is more pointed than the first protruding portion, and is in the form of a round cone or a round truncated cone with a rounded apex.

5. Non-woven material according to any one of paragraphs. 1-4, in which the first protruding parts 1 and the second protruding parts 2 are located in a mesh arrangement.

6. Non-woven material according to any one of paragraphs. 1-5, in which the orientation angle of the wall portion is from 50 ° to 130 °, and the orientation stability is 1.05 or more, and preferably the orientation stability is 1.1 or more, and the orientation angle is from 70 ° to 110 °.

7. Non-woven material according to any one of paragraphs. 1-6, in which the orientation of the fibers (q ₂₁ ) of the upper part of the second protruding part has an orientation angle of 0 ° or more and less than 50 °, or more than 130 ° and 180 ° or less, and the orientation stability is less than 1, 05.

8. Non-woven material according to any one of paragraphs. 1-7, in which all the first protruding parts that are adjacent to each other, and the second protruding parts that are adjacent to each other, connected by corrugated connecting parts.

9. Non-woven material according to any one of paragraphs. 1-8, in which the density of the fibers r ₁₁ in the upper part of the first protruding part is lower than the density of the fibers r ₁₂ in the upper part of the second protruding part.

10. Non-woven material according to any one of paragraphs. 1-9, in which the wall part is circular, and the orientations of the fibers differ between the parts of the wall part that the virtual line crosses through the center point on its horizontal section along the first direction on the surface, and between the parts of the wall part that the virtual line intersects, passing through a central point along a second direction on the surface.

11. Non-woven material according to any one of paragraphs. 1-10, in which the orientation of the fibers gradually changes from the first protruding part or the second protruding part to the wall part.

12. Non-woven material according to any one of paragraphs. 1-11, comprising a first protruding part extending to the first side of the surface in a horizontal projection of the non-woven fabric in the form of a sheet, and a second protruding part extending to the second side of the surface as the opposite side from the first surface, in which there are many first protruding parts and second protruding parts , alternately through the wall part, is distributed in two directions - the first direction and the second direction, in the horizontal projection of the nonwoven material, in which the fiber density (r _11a ) n and the first side of the surface of the upper part of the first protruding part is lower than the density of the fibers (r _11b ) on the second side of its surface (r _11a <r _11b ).

13. Non-woven material according to any one of paragraphs. 1-12, in which the density of the fibers on the first side of the surface of the first protruding part is from 10 fibers / mm ² to 50 fibers / mm ² and the density of the fibers on the second side of the surface is from 20 fibers / mm ² to 100 fibers / mm ² and more preferably, the fiber density (r _11a ) on the first side of the surface of the first protruding part is from 15 fibers / mm ² to 30 fibers / mm ² , and the fiber density (r _11b ) on the second side of the surface is from 45 fibers / mm ² to 70 fibers / mm ² .

14. Non-woven material according to any one of paragraphs. 1-13, in which the absolute value (| r _11a -r _11b |) of the fiber density difference on both sides of the surface of the upper portion of the first protruding portion is higher than the absolute value (| r _21a -r _21b |) of the fiber density difference on both sides of the surface top of the second protruding part.

15. Non-woven material according to any one of paragraphs. 1-14, in which the ratio (r _11b / r _11a ) between the densities of the fibers on the first side of the surface and the second side of the surface of the first protruding part is from 2 to 5.

16. Non-woven material according to any one of paragraphs. 1-15, in which the orientation of the fibers (q ₁₁ ) of the upper part of the first protruding part and the orientation of the fibers (q ₂₁ ) of the upper part of the second protruding part are different.

17. Non-woven material according to any one of paragraphs. 1-16, in which the orientation of the fibers of the upper part of the first protruding part is higher than the orientation of the fibers of the upper part of the second protruding part (q ₁₁ > q ₂₁ ).

18. Non-woven material according to any one of paragraphs. 1-17, in which in the orientation of the fibers of the upper part of the second protruding part, the orientation of the fibers (q _21a ) on the first side of the surface and the orientation of the fibers (q _21b ) on the second side of the surface are almost the same.

19. Non-woven material according to any one of paragraphs. 1-18, in which the number of fibers (u ₁ ) of the first protruding part and the number of fibers (u ₂ ) of the second protruding part are essentially the same.

20. Non-woven material according to any one of paragraphs. 1-19, in which the first direction and the second direction on the surface of the sheet intersect at an angle from 30 ° to 90 °.

21. Non-woven material according to any one of paragraphs. 1-20, in which the first direction and the second direction on the sheet surface intersect at right angles.

22. Non-woven material according to any one of paragraphs. 1-21, in which the internal parts of both the first protruding part and the second protruding part are cavities.

23. Non-woven material according to any one of paragraphs. 1-22, in which both the first protruding part and the second protruding part are protruding parts in the form of a hemisphere or in the form of a cone with a rounded apex.

24. Non-woven material according to any one of paragraphs. 1-23, in which in the second protruding part, the fibers are oriented so that they converge towards the upper part of the protruding part.

25. Non-woven material according to any one of paragraphs. 1-24, in which the density of the fibers in the first protruding part is from 30 fibers / mm ² to 150 fibers / mm ² and more preferably from 60 fibers / mm ² to 100 fibers / mm ² .

26. Non-woven material according to any one of paragraphs. 1-25, in which the density of the fibers in the second protruding part is from 150 fibers / mm ² to 600 fibers / mm ² and preferably from 300 fibers / mm ² to 550 fibers / mm ² .

27. Non-woven material according to any one of paragraphs. 1-26, in which the difference between the density of the fibers in the first protruding part and the density of the fibers in the second protruding part is 150 fibers / mm ² or more.

28. Non-woven material according to any one of paragraphs. 1-27, in which the interval n between the lines that form the first protruding part 1 and the second protruding part 2 is from 1 mm to 15 mm and preferably from 2 mm to 8 mm

29. Non-woven material according to any one of paragraphs. 1-28, in which the average surface density of the entire sheet is from 10 to 100 g / m ² and preferably from 20 to 50 g / m ² .

30. Non-woven material according to any one of paragraphs. 1-29, in which when the sheet thickness (T) of the nonwoven material at low pressure (0.05 × 10 ³ Pa), the thickness (T _p ) under pressure conditions of 3.5 × 10 ³ Pa is from 20 to 70% of the thickness (T ) before applying pressure.

31. Non-woven material according to any one of paragraphs. 1-30, in which the orientation of the fibers (r ₂₁ ) in the thickness direction in the upper part of the second protruding part is lower than the orientation of the fibers (r ₃ ) in the thickness direction of the wall part.

32. Non-woven material according to any one of paragraphs. 1-31, in which the number of fusion points of the fibers of the first protruding part (n ₁ ) is less than the number of fusion points of the fibers of the second protruding part (n ₂ ).

33. Non-woven material according to any one of paragraphs. 1-32, in which the number of fusion points of the fibers of the first protruding part (n ₁ ) is from 30 points / mm ² to 130 points / mm ² and preferably from 50 points / mm ² to 100 points / mm ² , and the number of fusion points of fibers the second protruding part (n ₂ ) is from 250 dots / mm ² to 500 dots / mm ² and preferably from 300 dots / mm ² to 450 dots / mm ² .

34. Non-woven material according to any one of paragraphs. 1-33, in which the ratio between the thickness of the layer (S ₁ ) of the upper part of the first protruding part, the thickness of the layer (S ₂ ) of the upper part of the second protruding part and the thickness of the layer (S ₃ ) of the wall part is such that S ₁ > S ₃ > S ₂ .

35. Non-woven material according to any one of paragraphs. 1-34, in which the compressive strength is from 0.01 to 0.35, and this non-woven material contains a first protruding part extending to the first side of the surface in a horizontal projection of the non-woven material in the form of a sheet, and a second protruding part extending to the second the surface side as the opposite side to the first surface, where the plurality of first protruding parts and second protruding parts, alternately through the wall part, is distributed in two directions in the first direction and the second direction enii, in horizontal projection of the nonwoven material, wherein at simultaneous admission clutch contacting flat surfaces with a plurality of first protruding portions and the plurality of second protruding portions of the nonwoven material on both sides of the formed reticulated spaces extending in the direction of the contacting surface between the flat surfaces and a nonwoven material.

36. Non-woven material according to any one of paragraphs. 1-35, where the non-woven material is a fibrous web, and its constituent fibers are fused when heated.

37. Non-woven material according to any one of paragraphs. 1-36, in which, when compressing the nonwoven material in the direction of the surface with a pressure of 50 gf / cm ^{2 of the} non-deformable pressing surface, mesh spaces are maintained between the pressing surface and the nonwoven material.

38. Non-woven material according to any one of paragraphs. 1-37, where when compressing the nonwoven material in the direction of the surface with a pressure of 0.5 gf / cm ² ) of the undeformable pressing surface, the ratio (S _0.5 / Sa) between the contact area S _{0.5 of the} pressing surface and the nonwoven material and the unitary total area Sa the pressing surface is from 0.1 to 0.4.

39. Non-woven material according to any one of paragraphs. 1-38, where when compressing the non-woven material in the direction of the surface with a pressure of 0.5 gf / cm ² non-deformable pressing surface, the ratio (S _0.5 / Sa) between the contact area S _{0.5 of the} pressing surface and the non-woven material and the unitary total area Sa of pressing the surface is from 0.12 to 0.35 and preferably from 0.15 to 0.3.

40. Non-woven material according to any one of paragraphs. 1-39, where when compressing the nonwoven material in the direction of the surface with a pressure of 50 gf / cm ^{2 of} non-deformable pressing surface, the ratio (S ₅₀ / Sa) between the contact area S _{50 of the} pressing surface and the non-woven material and the unitary total area Sa of the pressing surface is from 0.3 up to 0.9.

41. Non-woven material according to any one of paragraphs. 1-40, in which the ratio (S ₅₀ / Sa) between the contact area S _{50 of the} pressing surface and the nonwoven material and the unitary total area Sa of the pressing surface is from 0.4 to 0.85 and preferably from 0.5 to 0.8.

42. Non-woven material according to any one of paragraphs. 1-41, in which the ratio (T ₅₀ / T _0,5 ) between the thickness of the sheet T ₅₀ when compressing the nonwoven material in the direction of the surface with a pressure of 50 gf / cm ² non-deformable pressing surface and the thickness of the sheet T _0,5 when compressing with a pressure of 0.5 gf / cm ² (in the same manner as above, is from 0.1 to 0.4.

43. Non-woven material according to any one of paragraphs. 1-42, in which the ratio (T ₅₀ / T _0,5 ) between the thickness of the sheet T ₅₀ when compressing the nonwoven material in the direction of the surface with a pressure of 50 gf / cm ² non-deformable pressing surface and the thickness of the sheet T _0,5 when compressing with a pressure of 0.5 gf / cm ² ) in the same manner as above, is from 0.15 to 0.35.

44. Non-woven material according to any one of paragraphs. 1-43, in which the thickness of the layer of the first protruding part, the thickness of the layer of the second protruding part and the layer thickness of the wall part of the nonwoven material are practically the same.

45. Non-woven material according to any one of paragraphs. 1-44, in which the thickness variation coefficient described below is from 85 to 115% and preferably from 90 to 110%:

The coefficient of change in thickness (%) = thickness in the wet state (mm) / thickness in the dry state (mm) × 100 (numerical formula 1).

46. Non-woven material according to any one of paragraphs. 1-45, which is located between the upper material and the absorbent element, forming an absorbent product.

47. An absorbent product in which the nonwoven material according to any one of paragraphs. 1-46 is applied to the top sheet, with its first protruding parts directed towards the skin.

Examples

The present invention will now be described in more detail based on the following examples, but the present invention is not intended to be limited by these examples.

Examples and comparative examples with respect to the first aspect

Example 1

A bicomponent fiber containing a central core and a sheath having a density of 2.4 dtex and a length of 51 mm, the bicomponent fiber including polyethylene terephthalate as a central core and polyethylene as a sheath, was fed from a card machine to a web forming device so that the specific gravity was 27 g / m ² . In the web forming apparatus, the aforementioned fibrous web was fixed on a base (8 mm pitch in the machine direction, 4 mm pitch in the transverse direction) having numerous protrusions and having breathability. The shape of the protrusions of the base was a solid shape with a rounded triangular surface, oriented in the transverse direction and provided with holes through which hot air flow entered in a place surrounded by two protrusions, and the structure of the base, including the protrusions and holes, was not a structure in which combined numerous components, and a structure that was unified, and which did not contain the compounds used. The width of the protrusions in the transverse direction was 1.5 mm, the width (length) in the machine direction was 2.5 mm, and the height of the protrusion was 3 mm. The hot air stream (temperature 145 ° C., air speed 37 m / s) was then blown into the fibrous web onto the base to form the fibrous web along the protrusions on the base and fused each of the fibers with a structure such as a central core and sheath. The non-woven material made in this way as a result of thermal melting was removed and used as the test sample of the non-woven material 1.

Example 2

A test sample of the nonwoven fabric 2 was made in the same manner as in Example 1, except that the hot air flow conditions were 140 ° C and the air speed was 37 m / s.

Example 3

A test sample of the nonwoven material 3 was made in the same manner as in Example 1, except that the hot air flow conditions were 140 ° C and the air speed was 50 m / s.

Example 4

A test sample of non-woven material 4 was made in the same manner as in Example 1, except that the hot air flow conditions were 145 ° C and the air speed was 50 m / s.

Example 5

A test sample of nonwoven material 5 was made in the same manner as in Example 1, except that the hot air flow conditions were a temperature of 150 ° C and an air flow velocity of 30 m / s.

Example 6

A test sample of nonwoven material 6 was made in the same manner as in Example 1, except that the hot air flow conditions were a temperature of 150 ° C and an air flow velocity of 37 m / s.

Example 7

A test sample of nonwoven material 7 was made in the same manner as in Example 1, except that the hot air flow conditions were a temperature of 150 ° C and an air flow velocity of 50 m / s.

Comparative Example 1

Using the method described in example 1 of patent application JP-A-2008-25081, a test sample of the nonwoven fabric c1 with a change in surface density was made. The investigated sample of non-woven material c1 was distinguished by the absence of independent concave parts due to the presence of an uneven shape in the form of a strip, as well as due to the presence of holes. A diaper was made using a test sample of nonwoven fabric c1 instead of a test sample of nonwoven fabric 1 in the example.

Reference Example 2

In the same manner as in Example 1 of JP-A-03-137258, a nonwoven fabric having holes was made. Details are described as follows.

A cloth containing fibers with a central core and a sheath, measuring 2.4 dtex × 51 mm, was made from polyethylene terephthalate and polyethylene using a traditional carding machine. The canvas was then clamped between an uneven mesh and a simple weave, which was breathable, and air was introduced from the side of the simple weave. The canvas was pressed into the concave parts of the uneven mesh, and a web was made having loose and dense parts of the fibers that were located at a given step. After that, the web in this state was passed through hot air at 140 ° C for fusion in the polyethylene part and connection. As a result of this, a test sample of non-woven material c2 was manufactured having a roughness with a given step and holes in concave parts.

Reference Example 3

In the same manner as in Example 1 of JP-A-08-246321, a nonwoven fabric having holes was made. The following is a detailed description.

A cloth containing fibers with a central core and sheath, having dimensions of 3.3 dtex × 51 mm, was made of polyethylene terephthalate and polyethylene using a traditional carding machine. The canvas on a simple weave mesh with air permeability was then passed through hot air at 140 ° C for fusion in the polyethylene part and the compound, and a test sample of c3 non-woven fabric in the form of a sheet was obtained. After this, the holes were made using studs.

Reference Example 4

A test sample of non-woven material c4 was made in the same manner as in example 1 of patent application JP-A-2008-289662. The test sample of c4 nonwoven fabric is characterized by the presence of independent convex shapes and is used as a sheet material having amortization properties sufficient for the top sheet.

Using the aforementioned test samples of nonwoven material, the following measurement tests were performed.

According to the above results, the nonwoven fabric (test sample 1) in a preferred embodiment of the present invention had a high fiber orientation in the upward direction of the wall portion, and furthermore, the fiber orientation was maintained throughout the entire annular wall portion. The thickness was limited and the specific gravity was suitable, but an extremely high KES WE value was obtained. It turned out that in addition to the orientation of the fibers of the aforementioned wall portion, extremely good cushioning properties can be obtained.

Methods for measuring the estimated parameters, including those implemented in the above examples, were as described below.

Specific gravity

The specific gravity of the nonwoven material was measured as follows. First, the nonwoven material was cut into samples having dimensions of 250 mm × 200 mm, and they were used as test samples. The test sample was placed on an electronic balance (regardless of manufacturer). In this state, the mass was measured, and this mass was divided by area. After that, the obtained value was used as specific gravity (g / cm ² ). The measurement was carried out at three points, and the average value was taken as the measured value.

KES Compression Tester Evaluation

Using a KES compression test apparatus (trade name KES FB-3) manufactured by KATO TECH Co., Ltd., compression characteristics of a nonwoven fabric up to 5.0 × 10 ³ Pa were evaluated in a normal mode and the compression ability was read. described below.

Sheet Thickness Measurement (T)

Using a KES compression test apparatus (KES FB-3 manufactured by KATO 25 TECH Co., Ltd.), compression characteristics of a nonwoven fabric up to 5.0 × 10 ³ Pa were evaluated in normal mode and thickness (T) at low pressure application (0.05 × 10 ³ Pa) was read from the tables. The measurements were carried out at three points, and the average value was taken as the measured value.

Thickness measurement under pressure in the compression direction

Using a KES compression test apparatus (KES FB-3) manufactured by KATO TECH Co., Ltd., compression characteristics of a nonwoven fabric up to 5.0 × 10 ³ Pa were evaluated in normal mode, and the thickness under pressure 3, 5 × 10 ³ Pa was read from the table. The measurements were carried out at three points, and the average value was taken as the measured value. This value was preferably from 0.8 to 2.0.

Thickness measurement under pressure in the recovery direction after deformation

Using a KES compression test apparatus (KES FB-3) manufactured by KATO TECH Co., Ltd., compression characteristics of a nonwoven fabric up to 5.0 × 10 ³ Pa were evaluated in normal mode, and the thickness under pressure 3, 5 × 10 ³ Pa during recovery after compression deformation was read from the table. The measurements were carried out at three points, and the average value was taken as the measured value. This value was preferably from 0.6 to 1.8.

Depreciation Measurement

Using a KES compression test apparatus (KES FB-3 manufactured by KATO 20 TECH Co., Ltd.), compression characteristics of a nonwoven fabric up to 5.0 × 10 ³ Pa were evaluated in normal mode, and the thickness at a pressure of 3 , 5 × 10 ³ Pa was read from the table. The value was divided by the thickness T, and the obtained value was used to evaluate the depreciation properties. The measurements were carried out at three points, and the average value was taken as the measured value. This value was preferably from 37 to 80%.

Fiber orientation measurement

Using a JCM-5100 scanning electron microscope (trade name) manufactured by JEOL Ltd., the sample was set so that the z axis direction in FIG. 1 passed from top to bottom and an image was printed in a direction perpendicular to the measured surface of the sample (the increase at which 10 or more measured fibers could be measured was an increase of 50 to 300 times), and the fibers were observed on a transparent polyethylene terephthalate (PET) sheet . The image was transferred to a computer and converted to binary using the standalone version of Nexus New Qube image processing software (trade name) manufactured by Nexus Corporation. After that, using the Fiber Orientation Analysis 8.13 Single fiber orientation analysis software (software name), the orientation angle and orientation stability were obtained from the binary image. The measurement results of each test sample are presented in table 1. The orientation angle represents the angle at which the fibers are most oriented, and the orientation stability represents stability at the orientation angle. When measuring the wall portion, a value close to 90 ° indicates the orientation of the fibers in an upward direction. A larger orientation stability value indicates that the fiber directions are the same. When the orientation stability is 1.05 or more, the fibers are considered oriented.

For explanation, using FIG. 5, when part 32 (or 34) of the wall part in the intended machine direction (line j ₁ ) is considered as the wall part (MD), part 31 (or 33) of the wall part in the estimated transverse direction (line j ₂ ) is the wall part ( CD), and in this respect, the orientation of the fibers of the two parts was measured. The measurement was carried out at three points, and the average value was taken as the measured value.

Absorption Time Measurement (for reference)

The top sheet was removed from a commercially available medium-sized breathable baby diaper (trade name Merries Sara-Sara Air-Through M Size) manufactured by Kao Corporation, and a test nonwoven sample having dimensions of 100 × 250 mm and its perimeter were applied instead fixed, receiving a baby diaper for evaluation. A load of 20 g / cm ^{2 was} uniformly applied to the aforementioned test sample of the nonwoven material. A tube having a cross-sectional area of 1000 mm ² was placed approximately at the center of the test sample, and artificial urine was poured from the tube. Physiological saline was used as artificial urine, and artificial urine was poured three times with 40 g every 10 minutes. Measured time (in seconds) until complete absorption.

Examples, basic examples and comparative examples according to the second aspect

Example 8

(1) Making the top sheet

The bicomponent fiber containing the central core and sheath was 2.4 dtex × 51 mm in size, where the two-component fiber included polyethylene terephthalate as the central core and polyethylene as the sheath, sent from the card machine to the web forming machine so that the surface density was 27 g / m ² . In the web forming apparatus, the aforementioned fibrous web was fixed on the base (the pitch was 10 mm in the machine direction, and the pitch was 5 mm in the transverse direction) having numerous protrusions and breathability. The shape of the protrusions of the base was a solid shape with a rounded triangular surface, oriented in the transverse direction and provided with holes through which hot air flow entered in a place surrounded by two protrusions, and the structure of the base, including the protrusions and holes, was not a structure in which Numerous components combined, but a structure that was unified and which did not contain the compounds used. The width of the protrusions in the transverse direction was 1.5 mm, the width (length) in the machine direction was 4.8 mm, and the height of the protrusion was 10.5 mm. The hot air stream (temperature 160 ° C, air flow rate 40 m / s) was then blown into the fibrous web on the base to make the fibrous web along the protrusions on the base and fused each of the fibers with a structure such as a central core and sheath. A nonwoven fabric made in this way by hot melt was removed and used as a test sample of a nonwoven fabric 8. A cross section of a test sample of a nonwoven fabric 8 at low pressure (0.05 × 10 ³ Pa) was observed using a VHX-1000 digital microscope manufactured by the company KEYENCE Corporation, magnified 20 times, and the resulting replacement drawing photograph is shown in FIG. 12. FIG. 13 is a cross-sectional view of a sheet under compression with a pressure of 3.5 × 10 ³ Pa. In addition, a photograph of this test sample 8 was taken from the first side of the surface, and it is shown in FIG. 14. In the photograph of FIG. 12, the upper part is the side of the first protruding parts, and the lower part is the side of the second protruding parts. In this example, a test sample 8 was made in which the machine direction is oriented in the x direction shown in FIG. 5.

(2) Making diapers

The top sheet was removed from a commercially available baby diaper (trade name Merries Sara-Sara Air-Through M Size) manufactured by Kao Corporation, and a test sample of nonwoven fabric 8 was laminated instead, and its perimeter was fixed to make a baby diaper for evaluation.

Example 9

A test sample of nonwoven material 9 was made in the same manner as in example 8, except that the surface density was 25 g / m ² . A diaper was made using a test sample of nonwoven fabric 9 instead of a test sample of nonwoven fabric 8 in the example.

Example 10

A test sample of nonwoven material 10 was made in the same manner as in example 8, except that the surface density was 30 g / m ² . a diaper was made using a test sample of nonwoven fabric 10 instead of a test sample of nonwoven fabric 8 in the example.

Example 11

A test sample of nonwoven material 11 was made in the same manner as in Example 8, except that the hot air flow conditions were 140 ° C and the air speed was 40 m / s. A diaper was made using a test sample of nonwoven material 11 instead of a test sample of nonwoven material 8 in the example.

Example 12

A test sample of nonwoven material 12 was made in the same manner as in Example 8, except that the hot air flow conditions were a temperature of 180 ° C and an air flow rate of 40 m / s. A diaper was made using a test sample of nonwoven material 12 instead of a test sample of nonwoven material 8 in the example.

Example 13

A test sample of the nonwoven material 13 was made in the same manner as in Example 8, except that the hot air flow conditions were a temperature of 160 ° C and an air flow velocity of 20 m / s. A diaper was made using a test sample of nonwoven fabric 13 instead of a test sample of nonwoven fabric 8 in the example.

Example 14

A test sample of the nonwoven material 14 was made in the same manner as in Example 8, except that the hot air flow conditions were 160 ° C and the air flow rate 80 m / s. A diaper was made using a test sample of nonwoven fabric 14 instead of a test sample of nonwoven fabric 8 in the example.

Example 15

A test sample of the nonwoven material 15 was made in the same manner as in Example 8, except that the hot air flow conditions were a temperature of 160 ° C and an air flow velocity of 100 m / s. A diaper was made using a test sample of nonwoven fabric 15 instead of a test sample of nonwoven fabric 8 in the example.

Example 16

A test sample of nonwoven material 16 was made in the same manner as in Example 8, except that the hot air flow conditions were a temperature of 200 ° C and an air flow rate of 80 m / s. A diaper was made using a test sample of nonwoven fabric 16 instead of a test sample of nonwoven fabric 8 in the example.

Reference Example 1

A test sample of the nonwoven fabric s1 was made in the same manner as in Example 8, except that the hot air flow conditions were 160 ° C and the air speed was 10 m / s. A diaper was made using a test sample of nonwoven fabric s1 instead of a test sample of nonwoven fabric 8 in the example.

Reference Example 2

A test sample of nonwoven fabric s2 was made in the same manner as in Example 8, except that the hot air flow conditions were a temperature of 160 ° C and an air flow velocity of 150 m / s. A diaper was made using a test sample of nonwoven fabric s2 instead of a test sample of nonwoven fabric 8 in the example.

Reference Example 5

A flat test sample of c5 nonwoven fabric was made without using a base with protrusions according to Example 8. A diaper was made using a test sample of c5 nonwoven fabric instead of a test sample of nonwoven fabric 8 in the example.

Reference Example 6

In the same manner as in Example 1 of Patent Application JP-A-03-137258, a bulk non-woven material was made that differs in the content of independent concave parts and the presence of holes, and also in that the fiber density (r ₁ ) of the first protruding part is higher than fiber density (r ₂ ) of the second protruding part. The following is a detailed description.

A web was made using a bicomponent fiber containing 2.4 dtex × 51 mm containing a central core and a sheath, and a two-component fiber containing polyethylene terephthalate as a central core and polyethylene as a sheath, and using a carding machine in the traditional way. The canvas was then clamped between an uneven mesh and a simple weave, which was breathable, and air was introduced from the side of the simple weave. The canvas was pressed into the concave parts of the uneven mesh, and a web was made having loose and dense parts of the fibers that were located at a given step. After that, the web in this state was passed through hot air at 140 ° C for fusion in the polyethylene part and connection. As a result of this, a test sample of non-woven material c6 was made having a roughness with a given step and holes in concave parts. A diaper was made using a test sample of nonwoven fabric c6 instead of a test sample of nonwoven fabric 8 in the example.

Reference Example 7

The test sample of non-woven material c7 was a non-woven fabric made by the method described in patent application JP-A-08-246321, and contained independent concave parts and holes. A diaper was made using a test sample of nonwoven fabric c7 instead of a test sample of nonwoven fabric 8 in the example.

Reference Example 8

According to the method described in example 1 of patent application JP-A-2008-25081, a test sample of non-woven fabric c8 with a change in surface density was made. The c4 nonwoven fabric sample under study is distinguished by the absence of independent concave parts due to the presence of an uneven shape in the form of a strip and the presence of holes. A diaper was made using a test sample of nonwoven fabric c8 instead of a test sample of nonwoven fabric 8 in the example.

Using the aforementioned diaper, the following measurement tests were carried out.

According to the above results, loose stools lingered exactly in the cup-shaped spaces of nonwoven materials (test samples 8-16) in a preferred embodiment of the present invention, and stool diffusion was effectively limited. In addition, it was found that the materials did not come in contact with the skin on the plane, and the texture is good, and furthermore, even after the excrement-holding materials came into contact with the skin at the points, itching sensation did not occur, and it was possible Provide extremely good wearing feeling. Reference examples 1 and 2 represent a situation in which production conditions have been changed significantly. In the studied sample s1, the volumetric effect was insufficient, and the effects of depreciation and excretion retention properties could not be manifested sufficiently. It was found that the sheet of the test sample s2 contained holes, the compressive strength deteriorated, and thus the effects of depreciation and excretion retention properties could not be manifested sufficiently.

On the other hand, in comparative examples, the test sample c1 was flat, and thus, the effects of depreciation and excretion retention properties could not be manifested sufficiently. The test sample c2 and test sample c3 contained holes, the compressive strength deteriorated, and thus, the effects of depreciation and excretion retention properties could not be manifested sufficiently. It was found that the studied sample c4 had an uneven shape in the form of a strip, it did not contain independent concave parts, and thus, the diffusion of loose stools could not be limited, and the effect of excretion retention could not be manifested sufficiently.

Methods for measuring evaluation parameters, including those carried out in the above examples, were used as described below.

Uneven shape

The aforementioned nonwoven material was placed in a horizontal position and the existence of irregularities on the surface of the nonwoven material was determined.

O: uneven shapes

×: no uneven shapes

Independent concave parts

The aforementioned nonwoven material was placed in a horizontal position and the separation of the concave part of the nonwoven material from the adjacent concave part and its independence were determined.

O: independent concave parts

×: no independent concave parts

Holes

The aforementioned nonwoven material was placed in a horizontal position and the presence of holes in the independent concave portion of the nonwoven material was determined.

O: holes

×: no holes

Measurement of sheet thickness (T) and sheet thickness (T _p ) under pressure

Using a KES compression test apparatus (KES FB-3) manufactured by KATO TECH Co., Ltd., compression characteristics of a nonwoven fabric up to 5.0 × 10 ³ Pa were evaluated in normal mode and thickness (T) upon application low pressure (0.05 × 10 ³ Pa) and thickness (T _p ) at a pressure of 3.5 × 10 ³ Pa were read from the tables.

Assessment Methods

A baby diaper (test sample) was placed in a horizontal position, 10 g of artificial liquid stool (bentonite, glycerin, water EMULGEN 130 K (trade name, surfactant manufactured by Kao Corporation) was mixed in a ratio of 28: 14: 114: 14. and the viscosity of the resulting mixture was adjusted to 300 mPa • s) was poured into the central part (urination point) without pressure at a speed of 2 g / s, and the resulting diaper was kept for 5 minutes. After that, the transparent polyethylene terephthalate sheet was carefully placed on the surface of the upper sheet, and then the weight was set on the transparent polyethylene terephthalate sheet, creating a pressure of 3.5 × 10 ³ Pa, which was held for 5 minutes. After that, the pressure was removed and the transparent polyethylene terephthalate sheet was removed. The mass of artificial liquid stool adhering to the transparent polyethylene terephthalate sheet was calculated by measuring the mass of the transparent polyethylene terephthalate sheet before and after applying pressure, and this mass was considered as the amount of liquid stool adhering to the skin. In addition, the area over which artificial loose stool was spread after pressure was applied was measured, and this area was considered as the diffusion area of loose stool.

Fiber density measurement

The cut surface of a part of the nonwoven material was observed with magnification using a scanning electron microscope (the magnification of which is regulated so that it is possible to measure from 30 to 60 cross-sections of the fibers (magnification from 150 to 500 times) (150 times magnification was used in this example); number of cross-sections of the fibers were calculated and the field of view area, wherein the measured number of cross sections of the fibers. Then, the value counted in the number of cross sections of fibers per 1 mm ^2, and this value was used as the density of the fibers (fibers / mm ² ). The measurement was carried out at three points, and the average was used as the density of the fibers of the sample. In addition, with respect to the center of the part being observed, the midpoint between 11a and 11b or the midpoint between 21a and 21b shown in FIG. The 2 upper parts each of the first protruding part or the second protruding part was a central part.

- Scanning electron microscope JCM-5100 (trade name) manufactured by JEOL Ltd.

The first side of the surface of the upper part of the first protruding part 11a and the second side of the surface of the upper part 11b of the first protruding part, the first side of the surface of the upper part 21a of the second protruding part, and the second side of the surface of the upper part 21b of the second protruding part can be functionally considered according to the present invention. To determine the measurement location, as described above, when the corresponding point is observed in the direction of the sheet thickness T, the middle of the thickness (middle point) is considered as the midpoint of the two, and 11a and 21a are considered as the first side of the corresponding surface, and 11b and 21b are considered as the second side of the corresponding surface.

Fiber orientation measurement

Using a JCM-5100 scanning electron microscope (trade name) manufactured by JEOL Ltd., the sample was set so that the z axis direction in FIG. 1 passed from top to bottom and an image was printed in a direction perpendicular to the measured surface of the sample (an increase in which 30-60 or more measured fibers could be measured was an increase of 50 to 300 times), and the fibers were observed on transparent polyethylene terephthalate (PET ) sheet. The image was transferred to a computer and converted to binary using the standalone version of Nexus New Qube image processing software (trade name) manufactured by Nexus Corporation. After that, using the Fiber Orientation Analysis 8.13 Single fiber orientation analysis software (software name), the orientation angle and orientation stability were obtained from the binary image. Orientation angle is the angle at which the fibers are most oriented, and orientation stability is stability at orientation angle. When measuring the wall portion, a value close to 90 ° indicates the orientation of the fibers in an upward direction. A larger orientation stability value indicates that the fiber directions are the same. When the orientation stability is 1.05 or more, the fibers are considered oriented. The measurement was carried out at three points, and the average values were used as the orientation angle and the orientation stability of the sample.

Fiber count

- The thickness (S1) of the upper part of the first protruding part and the thickness (S2) of the upper part of the second protruding part are shown in FIG. 2 was measured by increasing to a size at which the area measured by a VHX-1000 digital microscope manufactured by KEYENCE Corporation is sufficiently included in the field of view and can be measured (magnification from 10 to 100 times). The measurement was carried out five times, and the average value was used as the thickness (mm) of the upper part of the first protruding part or the upper part of the second protruding part of the sample.

- The number of fibers per 1 mm ^{2 was} measured using the method for measuring fiber density described above.

- The number of fibers was evaluated by measuring the number of fibers (fibers) per thickness (mm) × (per) 1 mm ² . Thus, when the number of fibers per thickness × (by) 1 mm ^{2 of the} upper part of the first protruding part was almost equal to the number of fibers of the upper part of the second protruding part, the number of fibers (fibers / mm ³ ) was also determined equal. The meaning of the term “almost equal” includes the difference within the measurement error.

Fusion Point Measurement

The cut surface of a part of the nonwoven material was observed with magnification using a scanning electron microscope (the magnification of which is regulated so that it is possible to measure from 30 to 60 points of fiber fusion; the increase was from 150 to 500 times), and the number of fiber fusion points in a certain area was calculated. In addition, with respect to the center of the observed part, the midpoint between 11a and 11b or the midpoint between 21a and 21b shown in FIG. 2, the upper part of each of the first protruding part or the second protruding part was a central part. After that, the value was converted to the number of fiber fusion points per 1 mm ² , and this number was used as the number of fiber fusion points (dots / mm ² ). The measurement was carried out at three points, and the average was used as the number of fusion points of the sample fibers.

- Scanning electron microscope JCM-5100 (trade name) manufactured by JEOL Ltd.

Examples and comparative examples with respect to the third embodiment

Example 17

A bicomponent fiber containing a central core and a sheath with dimensions of 2.4 dtex × 51 mm, where the two-component fiber contains polyethylene terephthalate as a central core and polyethylene as a sheath, is sent from a card machine to a web forming machine so that the surface density is 30 g / m ² . In the web forming apparatus, the hot air flow was directed at a temperature of 130 ° C and an air flow rate of 47.5 m / s to fix the aforementioned fibrous web on the base (the pitch was 8 mm in the machine direction and the pitch was 5 mm in the transverse direction) having numerous protrusions and breathability. The shape of the protrusions of the base was a solid shape with a rounded triangular surface, oriented in the transverse direction and provided with holes through which hot air flow came in at a place surrounded by the protrusion and the protrusion, and the structure of the base, including the protrusions and holes, was not a structure in which combined numerous components, and a structure that was unified, and which did not contain the compounds used. The width of the protrusions in the transverse direction was 1.5 mm, the width (length) in the machine direction was 3.5 mm, and the height of the protrusion was 3 mm. The hot air stream (temperature 145 ° C., air velocity 5 m / s) was then blown into the fibrous web onto the base to fabricate the fibrous web along the protrusions on the base and fused each of the fibers with a structure such as a central core and sheath. A non-woven fabric made in this way by hot melt was removed and used as a test sample of non-woven fabric 17. A cross-section of a test sample of non-woven fabric 17 was observed using a VHX-1000 digital microscope manufactured by KEYENCE Corporation at 20x magnification and obtained as a substitute drawing a photograph is shown in FIG. 15. In the photograph of FIG. 15, the upper part is the side of the first protruding parts, and the lower part is the side of the second protruding parts.

(2) Making diapers

The top sheet was removed from a commercially available medium-sized breathable baby diaper (trade name Merries Sara-Sara Air-Through M Size) manufactured by Kao Corporation, and a test sample of nonwoven fabric 17 was placed in its place, with the first side extending toward the surface skin, its perimeter was fixed, and received a baby diaper for evaluation.

Example 18

A test sample of nonwoven material 18 was made in the same manner as in Example 17, except that the hot air flow conditions were 130 ° C and the air speed was 50 m / s. A diaper was made using a test sample of nonwoven fabric 18 instead of a test sample of nonwoven fabric 17 in the example.

Example 19

A test sample of the nonwoven material 19 was made in the same manner as in Example 17, except that the hot air flow conditions were 130 ° C and the air flow velocity 52.5 m / s. A diaper was made using a test sample of nonwoven fabric 19 instead of a test sample of nonwoven fabric 17 in the example.

Example 20

A test sample of nonwoven material 20 was made in the same manner as in Example 17, except that the hot air flow conditions were 125 ° C and the air speed was 50 m / s. A diaper was made using a test sample of nonwoven material 20 instead of a test sample of nonwoven material 17 in the example.

Example 21

A test sample of nonwoven material 21 was made in the same manner as in Example 17, except that the hot air flow conditions were 135 ° C and the air speed was 50 m / s. A diaper was made using a test sample of nonwoven fabric 21 instead of a test sample of nonwoven fabric 17 in the example.

Reference Example 9

In the same manner as in Example 1 of JP-A-2008-25081, a laminated nonwoven fabric with strip protrusions was made. The following is a detailed description.

As the first fiber layer, fiber A was used, which had a structure such as a central core and a sheath of low density polyethylene (melting point 110 ° C) and polyethylene terephthalate, in which the average fineness was 3.3 dtex and the average fiber length was 51 mm, and which was coated with a hydrophilic substance. On the other hand, a fiber layer was used in which fiber A was mixed with fiber B, which had a structure such as a central core and a sheath of high density polyethylene (melting point 135 ° C) and polyethylene terephthalate, in which the average fineness was 3.3 dtex, and the average fiber length was 51 mm, and which was coated with a hydrophobic substance. Fiber A and fiber B were contained in the mixture at a ratio of 70:30, and the specific gravity was 15 g / m ² .

As the second fiber layer, a fiber layer was used, which was 100% fiber, which had a structure such as a central core and a sheath of high density polyethylene and polyethylene terephthalate, in which the average fineness was 4.4 dtex and the average fiber length was 38 mm. and which was coated with a hydrophilic substance. The specific gravity of this fibrous layer was 25 g / m ² .

Using the same device as in FIG. 8 and FIG. 9 in JP-A-2008-25081, fiber lamination was performed as described above, and a hot air stream was blown from the blower portion of the aforementioned device at a temperature of 105 ° C and an air flow rate of 1200 l / min, and then a test sample was made nonwoven fabric c9.

Reference Example 10

Non-woven material was made in the same manner as in example 1 of patent application JP-A-03-137258.

At first, the web, including fibers with a central core and a sheath, measuring 2.4 dtex × 51 mm, was made of polyethylene terephthalate and polyethylene using a traditional carding machine. The canvas was then clamped between an uneven mesh and a simple weave, which was breathable, and air was introduced from the side of the simple weave. The canvas was pressed into the concave parts of the uneven mesh, and a web was made having loose and dense parts of the fibers that were located at a given step. After that, the web in this state was passed through hot air at 140 ° C for fusion in the polyethylene part and connection. As a result of this, a test sample of c10 non-woven material was manufactured having a roughness with a given step and holes in the concave part.

Reference Example 11

The test sample of non-woven material c3 was a non-woven material made by the method described in example 1 of patent application JP-A-08-246321, by heating the core roller at 120 ° C and setting the surface density of 25 g / cm ² , and this non-woven material contained independent concave parts and holes. A diaper was made using a test sample of nonwoven fabric c11 instead of a test sample of nonwoven fabric 17 in the example.

Using the above nonwoven samples, the following measurement tests were performed.

Sheet thickness measurement

Using a KES compression test device (KES FB-3) manufactured by KATO TECH Co., Ltd., compression characteristics of a nonwoven fabric up to 5.0 × 103 Pa were evaluated in normal mode and thickness (T) when low pressures (0.05 × 103 Pa) were read from the tables.

Fiber density measurement

The section surface of a part of the nonwoven material was observed under magnification using a scanning electron microscope (the magnification of which is regulated so that approximately 30 to 60 cross sections of the fibers can be measured; the increase was 150 to 500 times) and the number of cross sections of the cut fibers per certain area (about 0.5 ^mm2) of the cut surface. In addition, with regard to the center of the observed part, the midpoints 11 and 12 of FIG. The 2 upper parts of the first protruding part and the second protruding part represented the central part. This value was then converted to the number of cross-sections of the fibers per 1 mm ² , and this number was used as the density of the fibers. The measurement was carried out at three points, and the average was used as the fiber density of the sample.

- Scanning electron microscope JCM-5100 (trade name) manufactured by JEOL Ltd.

Fiber orientation measurement

Using a JCM-5100 scanning electron microscope (trade name) manufactured by JEOL Ltd., an image was printed in a direction perpendicular to the measured surface of the sample (an increase in which 30-60 or more measured fibers could be measured was an increase from 50 to 300 times), and the fibers were observed on a sheet for a projector with an upper light source (OHP). A sheet for a projector with an upper light source was transferred to a computer and converted to binary using a standalone version of Nexus New Qube image processing software (trade name), manufactured by Nexus Corporation. The binary image was Fourier transform using Fiber Orientation Analysis 8.13 Single fiber orientation analysis software (trade name of the software) so as to obtain the energy spectrum and orientation angle and orientation stability from the distribution map of the approximate ellipse. Orientation angle is the angle at which the fibers are most oriented, and orientation stability is stability at orientation angle. A larger orientation stability value indicates that the fiber directions are the same.

The orientation angle and orientation stability q ₁₁ are the results of measurements of fibers located approximately in the central part in the thickness direction of the upper part 11 of the first protruding part.

Absorption Time Measurement

The top sheet was removed from a commercially available baby diaper (trade name Merries Sara-Sara Air-Through M Size) manufactured by Kao Corporation, and instead a test sample of nonwoven fabric having dimensions of 100 × 250 mm was applied and its perimeter was fixed to obtain baby diaper for evaluation. A load of 20 g / cm ^{2 was} uniformly applied to the aforementioned test sample of the nonwoven material. A tube having a cross-sectional area of 1000 mm ² was placed approximately at the center of the test sample, and artificial urine was poured from the tube. Physiological saline was used as artificial urine, and artificial urine was poured three times with 40 g every 10 minutes. Measured time (in seconds) until complete absorption. The measurement results of each test sample are presented in table 3 below.

Measuring the amount of back current fluid

The top sheet was removed from a commercially available baby diaper (trade name Merries Sara-Sara Air-Through M Size) manufactured by Kao Corporation, and instead a test sample of nonwoven fabric having dimensions of 100 × 250 mm was applied and its perimeter was fixed to obtain baby diaper for evaluation. A load of 20 g / cm ^{2 was} uniformly applied to the aforementioned test sample of the nonwoven material. A tube having a cross-sectional area of 1000 mm ² was placed approximately at the center of the test sample, and artificial urine was poured from the tube. Physiological saline was used as artificial urine, and artificial urine was poured three times in 40 g every 10 minutes, and then the load was removed 20 g / cm ² . Filter paper, to which a load of 4.9 kPa was applied, was placed on the test sample of nonwoven material and held for 2 minutes, and then the change in the weight of the filter paper was used as the amount of back flowing fluid (g). The measurement results of each test sample are presented in table 3 below.

According to the above results, it was found that for nonwoven materials (test samples 17-21) in preferred embodiments of the present invention, the fiber density at the top of a certain protruding part was suitable, and the fiber orientation at the top of another protruding part was also suitable. Thus, it was found that the nonwoven materials exhibited excellent properties, including a short absorption time and a small amount of back flowing fluid, as a top sheet and the like. for an absorbent article. In the c1-c3 samples under study, the fiber density and fiber orientation were not suitable, and thus, these effects could not be manifested sufficiently.

Examples and comparative examples with respect to the fourth embodiment

Example 22

The bicomponent fiber containing the central core and the sheath was 2.2 dtex × 51 mm in size, where the two-component fiber contained polyethylene terephthalate as the central core and polyethylene as the sheath, was sent from the card machine to the web forming machine so that the surface density was 27 g / m ² . In the web forming apparatus, the hot air stream was guided at normal temperatures to fix the aforementioned fibrous web on a base with a large number of protrusions and breathability. The shape of the protrusions of the base was a solid shape with a rounded triangular surface, oriented in the transverse direction and provided with holes through which hot air flow entered in a place surrounded by two protrusions, and the structure of the base, including the protrusions and holes, was not a structure in which combined numerous components, and a structure that was unified, and which did not contain the compounds used. The pitch of the base protrusions (the distance between the centers of the protrusions in horizontal projection) was 4 mm. The width of the protrusions in the transverse direction was 1.5 mm, the width (length) in the machine direction was 3.5 mm, and the height of the protrusion was 8 mm. After that, the hot air stream (temperature 130 ° C, air flow rate of 50 m / s) was blown into the fibrous web onto the base, and the fibrous web was molded along the protrusions of the base; and, changing the conditions of the hot air flow to a temperature of 145 ° C and an air flow velocity of 5 m / s, each fiber was fused with a structure such as a central core and sheath. The line speed was 100 m / min. A nonwoven fabric made in this way by hot melt was removed and used as a test sample of the nonwoven fabric 22. The cross-sectional images (Fig. 16) of the nonwoven fibrous test specimen obtained in Example 22 and the cross-sectional image (Fig. 17) under pressure are presented. 0.5 g / cm ² .

Example 23

A test sample of nonwoven material 23 was obtained in the same manner as in the above example 22, except that the pitch of the base protrusions was 5 mm.

Reference Example 12

In the same manner as in Example 1 of JP-A-2008-25081, the non-woven fabric c1 is in the form of a harmonic. The following is a detailed description.

As the first fiber layer, fiber A was used, which had a structure such as a central core and a sheath of low density polyethylene (melting point 110 ° C) and polyethylene terephthalate, in which the average fineness was 3.3 dtex and the average fiber length was 51 mm, and which has been coated with a hydrophilic substance; and fiber B, which had a structure such as a central core and sheath of high density polyethylene (melting point 135 ° C) and polyethylene terephthalate, in which the average fineness was 3.3 dtex and the average fiber length was 51 mm, and which was coated with a hydrophobic substance . Fiber A and fiber B were contained in the mixture at a ratio of 70:30, and the specific gravity was 15 g / m ² .

As the second fiber layer, a fiber layer was used, which was 100% fiber, which had a structure such as a central core and a sheath of high density polyethylene and polyethylene terephthalate, in which the average fineness was 4.4 dtex and the average fiber length was 38 mm. and which was coated with a hydrophilic substance. The specific gravity of this fibrous layer was 25 g / m ² .

Using the same device as in FIG. 8 and FIG. 9 in JP-A-2008-25081, fiber lamination was performed as described above, and a hot air stream was blown from the blower portion of the aforementioned device at a temperature of 105 ° C and an air flow rate of 1200 l / min, and then a test sample was made c12 nonwoven fabric in harmonic shape.

Reference Example 13

In the same manner as in Example 1 of JP-A-03-137258, a nonwoven fabric having holes was made. The following is a detailed description.

A web was made including fibers with a central core and a sheath having dimensions 3 den × 51 mm from polyethylene terephthalate and polyethylene using a carding machine in the traditional way. The canvas was then clamped between an uneven mesh and a simple weave, which was breathable, and air was introduced from the side of the simple weave. The canvas was pressed into the concave parts of the uneven mesh, and a web was made in which the loose and dense parts of the fibers were made with a given step. After that, the web in this state was passed through hot air at 140 ° C to fuse them in the polyethylene part. As a result of this, a roughness was made with a given step, and a test sample of c13 nonwoven fabric with holes in concave parts was obtained.

Using the above nonwoven samples, the following measurement tests were performed.

According to the above results, it was found that the nonwoven materials (examples) in the preferred embodiments of the present invention had excellent characteristics, including good breathability, excellent cushioning and deformation properties, high absorption rate, and also did not adhere and were gentle to the skin when compared with comparative examples.

Methods for measuring the estimated parameters, including those implemented in the above examples, were as described below.

Thickness

An aluminum disk was made having a diameter of 50 to 60 mm and a load of 0.5 gf / cm ² . The thickness of the sheet onto which this aluminum disk was placed was measured using a laser displacement meter. The measurements were carried out at five points in any region of the sheet (provided that the regions on which the aluminum disks were placed did not overlap, and the average value was used as the sheet thickness T _0.5 . In addition, when the load of the aluminum disk was 50 g / cm ² , this value was used as a thickness of T ₅₀ .

Contact area

A transparent acrylic plate was prepared with a load of 0.5 gf / cm ² . A clear acrylic plate was placed on the sheet. An area of the central portion measuring 5 cm or more × 5 cm or more (Sa area) was observed using a VHX-1000 microscope (trade name) manufactured by KEYENCE Corporation at five times magnification, and each region with clear acrylic the plate came into contact with the sheet, was surrounded using the smooth line function of the VHX-900 microscope, and the surrounded area was measured. The sum of the areas of the measured contact areas was used as S _0.5 .

In addition, a transparent acrylic plate was placed on the sheet, and then loads were set at the edges of the transparent acrylic plate, which were adjusted so that the uniform load on the sheet was 50 gf / cm ² . After that, the area of each contact area was measured in the same manner as described above. The sum of the areas of the measured contact areas was used as S ₅₀ .

Compression Hardness (LC)

The compressive hardness (LC) of the nonwoven was measured using the KES-FB3-AUTO-A texture measuring system (trade name manufactured by KATO TECH Co., Ltd.. The conditions set for the measurement included sensitivity level 2, compression speed 50 mm / s, data entry interval 0.1 s, pressure application area 2 cm ² (attached clamp); the dimensions of the measured sheet were 15 cm × 15 cm, and the sheet was placed in the center of the measuring table. at three points and average value was used as the measured value.

Cushioning properties

When the tester pressed and released the sheet with his hand, he assessed his sensation. With the participation of three testers, more opinions were used as the results of the evaluation sheet.

Taking into account practical requirements, estimates of the measurement results were determined as follows.

A: when the sheet was pressed and released, its behavior during recovery from deformation was like a spring.

B: when the sheet was pressed and released, its behavior during restoration after deformation was detailed to the spring, but was manifested to a small extent. Alternatively, the behavior of the sheet during restoration after deformation was similar to a spring only in the process of pressing or releasing it.

C: when the sheet was pressed and released, it lacked spring-like behavior when recovering from deformation.

Easy deformation properties

When the tester folded the sheet, he assessed his sensation. With the participation of three testers, more opinions were used as the results of the evaluation sheet.

Taking into account practical requirements, estimates of the measurement results were determined as follows.

A: when the sheet was bent, it produced a feeling of softness. Alternatively, the sheet bent spontaneously.

B: when the sheet was bent, it produced a feeling of light stiffness. Alternatively, when the sheet was bent, a fold line appeared.

C: when the sheet was bent, it produced a feeling of stiffness. Alternatively, when the sheet was bent, a fold line appeared.

Absorption rate

A cut test sample of a nonwoven material having dimensions of 280 × 160 mm was placed on a cellulose absorbent element through an intermediate layer (breathable nonwoven material made by laminating a web having a surface density of 20 g / m ² and containing a bicomponent fiber with a central core and a linear sheath with a density of 3.3 dtex, and this two-component fiber included polyethylene terephthalate as a central core and polyethylene as a sheath as a component fiber; and polo a fiber having a surface density of 20 g / m ² and comprising a bicomponent fiber with a central core and a sheath with a linear density of 7.8 dtex, wherein this bicomponent fiber contained polyethylene terephthalate as a central core and polyethylene as a sheath as a component fiber). A load of 20 g / cm ^{2 was} uniformly applied to the aforementioned nonwoven material. A tube with an inner diameter of 36 mm was placed approximately at the center of the test sample, and physiological saline was poured from the tube. After that, physiological saline was poured three times in 40 g each time for 10 minutes, and after the solution was poured a third time, the time (in seconds) was measured until the solution was completely absorbed. The measurement results of each test sample are presented in the above table 4.

Taking into account practical requirements, estimates of the measurement results were determined as follows.

A: the time until complete absorption of the solution is within 180 s.

B: the time to complete absorption of the solution is from 180 to 300 s.

C: the time to complete absorption of the solution is 300 s or more.

Properties of the Current Fluid Back

In the aforementioned estimate of the absorption rate, 10 minutes after pouring the third solution, considering the poured portion as the center, 20 sheets of 4A filter paper manufactured by Advantec Toyo Kaisha, Ltd. (size 100 mm × 100 mm) were placed on it, and then applied load 3.5 kPa (3.5 kg, size 100 mm × 100 mm). Filter paper was removed 2 minutes after application of the load. The difference between the initial weight of the filter paper and its weight after application of pressure was measured as the amount of back flowing fluid.

Taking into account practical requirements, estimates of the measurement results were determined as follows.

A: the amount of back flowing fluid is 0.5 g or less.

B: the amount of back current fluid is from 0.5 to 1 g.

C: the amount of back current fluid is 1 g or more.

After describing the present invention with respect to these embodiments, the authors suggest that the present invention is not limited to any details of the description unless otherwise specified, but is construed broadly within the scope of its idea and scope, as defined in the accompanying claims.

This application claims the priority of patent application No. 2010-288535 filed in Japan on December 24, 2010, patent application No. 2010-288536 filed in Japan December 24, 2010, patent application No. 2010-288537 filed in Japan December 24, 2010, patent application No. 2010-288538, filed in Japan on December 24, 2010, and patent application No. 2011-271648, filed in Japan on December 12, 2011, each of which in its entirety is incorporated herein by reference.

Description of conventions

1 - The first protruding part

11 - The upper part of the first protruding part

11a - The first side of the surface of the upper part of the first protruding part

11b - The second side of the surface of the upper part of the first protruding part

1k - Interior spaces of the first protruding part

2 - The second protruding part

21 - The upper part of the second protruding part

21a - The first side of the surface of the upper part of the second protruding part

21b - The second side of the surface of the upper part of the second protruding part

2k - Interior spaces of the second protruding part

3 - Wall part

6 - Corrugated part

9 - Projection

10 - Nonwoven fabric

T - Sheet Thickness

S (S1, S2, S3) - Layer Thickness

71 - Bottom sheet

72 - Side Ruffle

73 - Absorbent element

75 - Side sheet

76 - Fixing tape

100 - Disposable diaper

V1, V2 - Continuous mesh space

Claims (25)

1. Non-woven material containing a first protruding part protruding to the first side of the surface in a horizontal projection of the non-woven material in the form of a sheet, and a second protruding part protruding to the second side of the surface as the opposite side from the first surface, the plurality of first protruding parts and second protruding parts alternately through the wall parts, distributed in two directions from the first direction and the second direction, in a horizontal projection of the nonwoven material, while the wall part has a radial orientation of the fibers converging towards the upper part of the second protruding part, essentially at any point in the direction of the surface formed as the first direction and the second direction. 2. The nonwoven fabric according to claim 1, wherein the first protruding parts that are adjacent to each other and the second protruding parts that are adjacent to each other are connected by corrugated connecting parts. 3. The nonwoven fabric according to claim 1, wherein the density of fibers r ₁₁ in the upper part of the first protruding part is lower than the density of fibers r ₁₂ in the upper part of the second protruding part. 4. The non-woven fabric according to claim 1, wherein the wall portion is circular and the fiber orientations differ between parts of the wall that intersect with a virtual line passing through a central point on its horizontal section along the first direction on the surface, and in parts of the wall part that intersect a virtual line passing through a central point along a second direction on the surface. 5. The non-woven material according to claim 1, in which the orientation of the fibers gradually changes from the first protruding part or the second protruding part to the wall part. 6. The nonwoven material according to claim 1, comprising a first protruding part protruding to the first side of the surface in a horizontal projection of the non-woven material in the form of a sheet, and a second protruding part protruding to the second side of the surface as the opposite side from the first surface, the plurality of first protruding parts and the second protruding parts, alternately through the wall part, are distributed in two directions: the first direction and the second direction, in the horizontal projection of the nonwoven material, while the density of the fiber con (r _11a ) on the first side of the surface of the upper part of the first protruding part is lower than the density of the fibers (r _11b ) on its second side of the surface (r _11a <r _11b ). 7. The nonwoven material according to claim 1, in which the absolute value

the difference in fiber density on both sides of the surface of the upper part of the first protruding part is higher than the absolute value

the density difference of the fibers on both sides of the surface of the upper part of the second protruding part. 8. The nonwoven fabric according to claim 1, wherein the orientation of the fibers (q ₁₁ ) of the upper part of the first protruding part and the orientation of the fibers (q ₂₁ ) of the upper part of the second protruding part are different. 9. The nonwoven fabric according to claim 1, wherein in the orientation of the fibers of the upper part of the second protruding part, the orientation of the fibers (q _21a ) on the first side of the surface and the orientation of the fibers (q _21b ) on the second side of the surface are essentially the same. 10. The nonwoven fabric according to claim 1, wherein the first direction and the second direction on the sheet surface intersect at right angles. 11. The nonwoven material according to claim 1, in which the internal parts of both the first protruding part and the second protruding part are cavities. 12. The nonwoven fabric according to claim 1, wherein both the first protruding part and the second protruding part are protruding parts in the form of a hemisphere or in the form of a cone with a rounded apex. 13. The nonwoven fabric according to claim 1, wherein the fibers are oriented in the second protruding part so that they converge towards the upper part of the protruding part. 14. The non-woven material according to claim 1, wherein when the thickness of the sheet (T) of the non-woven material at low pressure (0.05 × 103 Pa), the thickness (T _p ) under pressure conditions of 3.5 × 103 Pa is from 20 to 70% thickness (T) before applying pressure. 15. The nonwoven fabric according to claim 1, wherein the orientation of the fibers (r ₂₁ ) in the thickness direction of the upper part of the second protruding part is lower than the orientation of the fibers (r ₃ ) in the thickness direction of the wall part. 16. The nonwoven material according to claim 1, in which the number of fusion points of the fibers of the first protruding part (n ₁ ) is less than the number of fusion points of the fibers of the second protruding part (n ₂ ). 17. The non-woven material according to claim 1, in which the compressive hardness is from 0.01 to 0.35, and the non-woven material contains a first protruding part protruding to the first side of the surface in the horizontal projection of the non-woven material in the form of a sheet, and a second protruding part protruding to the second side of the surface as the opposite side relative to the first surface, and many of the first protruding parts and second protruding parts, alternately through the wall part, are distributed in two directions: the first direction and T rum direction in the plan view of the nonwoven material, the contact flat surfaces allow engagement of the plurality of first protruding portions and the plurality of second protruding portions of the nonwoven material, and are formed on both sides of the reticulated space, distributed in the direction of the contacting surface between the flat surfaces and a nonwoven material. 18. The non-woven material according to claim 1, in which the non-woven material is a fibrous web and its constituent fibers are fused when heated. 19. The non-woven material according to claim 1, wherein when compressing the non-woven material in the direction of the surface with a pressure of 50 gf / cm ^{2 of an} undeformable pressing surface, mesh spaces between the pressing surface and the non-woven material are retained. 20. The non-woven material according to claim 1, wherein when compressing the non-woven material in the direction of the surface with a pressure of 0.5 gf / cm ² non-deformable pressing surface, the ratio (S _0,5 / Sa) between the contact area S _{0,5 of the} pressing surface and the non-woven material and the unitary total surface area Sa of the pressing surface is from 0.1 to 0.4. 21. The non-woven material according to claim 1, wherein when compressing the non-woven material in the direction of the surface with a pressure of 50 gf / cm ^{2 by an} undeformable pressing surface, the ratio (S ₅₀ / Sa) between the contact area S _{50 of the} pressing surface and the non-woven material and the unitary total area Sa of the pressing the surface is between 0.3 and 0.9. 22. The nonwoven material according to claim 1, in which the ratio (T ₅₀ / T _0.5 ) between the thickness of the sheet T ₅₀ when compressing the nonwoven material in the direction of the surface with a pressure of 50 gf / cm ² non-deformable pressing surface and the thickness of the sheet T _0,5 at compression pressure of 0.5 g / cm ² in the same manner as described above, is from 0.1 to 0.4. 23. The nonwoven material according to claim 1, wherein the layer thickness of the first protruding part, the layer thickness of the second protruding part, and the layer thickness of the wall portion of the nonwoven material are substantially the same. 24. The nonwoven material according to claim 1, which is located between the upper material and the absorbent element, forming an absorbent product. 25. An absorbent product in which the nonwoven material according to any one of paragraphs. 1-24 are applied to the top sheet, with its first protruding parts directed toward the skin.

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