WO2015045499A1

WO2015045499A1 - Process for producing nonwoven fabric, and nonwoven fabric

Info

Publication number: WO2015045499A1
Application number: PCT/JP2014/065494
Authority: WO
Inventors: 宏子川口; 小森　康浩; 麻央荒井
Original assignee: 花王株式会社
Priority date: 2013-09-24
Filing date: 2014-06-11
Publication date: 2015-04-02
Also published as: TW201527075A; CN105517523B; CN105517523A; JP2015086501A; JP5925835B2; BR112016006662A2

Abstract

Provided is a process for producing nonwoven fabric (10) by conveying a thermoplastic-fiber-containing web (50) to a heated support (110) having a rugged shape and blowing hot air (W1, W2) toward the support (110) from above the web (50) to impart a rugged shape to the web (50), the process including: a step in which the support (110) is heated to a temperature in the range of from the glass transition point of the fibers constituting the web (50) to the melting point thereof; a step in which the fibers of the web (50) are provisionally fusion-bonded to one another by the blowing of first hot air (W1) so that the rugged shape is maintained; and a step in which second hot air (W2) that has a higher temperature than the first hot air (W1) is blown to fusion-bond the fibers of the web (50) to one another in the state of retaining the rugged shape, thereby fixing the rugged shape.

Description

Nonwoven fabric manufacturing method and nonwoven fabric

The present invention relates to a nonwoven fabric manufacturing method and a nonwoven fabric.

In absorbent articles such as incontinence pads, sanitary napkins and disposable diapers, excretory fluid is permeated in the thickness direction from the top sheet and held by the absorbent body. In this liquid permeation route, the top sheet is likely to be in close contact with the skin while directly receiving excretory fluid. Since measures against skin troubles such as rough skin are indispensable in such a close contact state, various proposals have been made on the surface sheet from the viewpoint of a good wearing feeling.

For example, Patent Document 1 describes a product in which a surface sheet has double-sided irregularities and a hydrophobic skin care agent is adhered to both sides of a protruding portion in contact with the skin in order to enhance the skin care effect on the skin. Patent Document 2 describes a fiber sheet having an uneven structure. A fiber sheet has a fiber inside a convex part. Moreover, the top part is hydrophobic. Further, the portion other than the top has a lower hydrophobicity than the top.

JP 2012-143543 A JP 2006-183168 A

The present invention has a concavo-convex shape, conveys a web containing thermoplastic fibers to a heated support, and blows hot air from above the web toward the support to shape the concavo-convex shape on the web. A method for producing a nonwoven fabric, the step of heating the support to a temperature range of not less than the glass transition point of the fibers constituting the web and not more than the melting point, and the fibers of the web by the first hot air blowing The step of temporarily fusing the concavo-convex shape and the second hot air having a temperature higher than that of the first hot air is blown, and the fibers of the web are fused together while the concavo-convex shape is maintained. The manufacturing method of a nonwoven fabric provided with the process of fixing the said uneven | corrugated shape is provided.
The present invention has a first projecting portion projecting on the first surface side of the nonwoven fabric sheet in plan view and having an inner space, and projecting on the second surface side opposite to the first projecting portion and having an inner space. And a plurality of the first protrusions and the second protrusions that are alternately and continuously arranged through the wall portions in different directions intersecting the planar view of the nonwoven fabric. The first protrusions and the adjacent second protrusions are nonwoven fabrics that are continuously connected in an oblique direction in plan view with respect to each of the different directions via a ridge portion, and the nonwoven fabrics. When pressurized with a pressure of 0.05 kPa, the height in the thickness direction of the first protrusion is higher than the height in the thickness direction of the ridge, and the rising angle of the wall of the first protrusion is 0 ° or more. A non-woven fabric that is 20 ° or less is provided.

The above and other features and advantages of the present invention will become more apparent from the following description with reference to the accompanying drawings as appropriate.

It is the fragmentary sectional view showing one desirable embodiment of the nonwoven fabric concerning the present invention. It is the plane arrangement | positioning figure which showed the preferable example of arrangement | positioning of the 1st, 2nd protrusion part of the nonwoven fabric which concerns on this embodiment. It is principal part sectional drawing which showed an example of the ridge part of the nonwoven fabric which concerns on this embodiment. It is drawing which showed an example of the fiber orientation in the wall part of the 1st protrusion part of the nonwoven fabric which concerns on this embodiment, (a) is principal part sectional drawing, (b) is a top view. It is drawing which showed an example of the fiber orientation in the wall part of the 2nd protrusion part of the nonwoven fabric which concerns on this embodiment, (a) is principal part sectional drawing, (b) is a top view. It is principal part sectional drawing which showed an example of the dimension of each site | part of the nonwoven fabric which concerns on this embodiment. It is principal part sectional drawing which showed an example of the top space | interval of the nonwoven fabric which concerns on this embodiment. It is principal part sectional drawing which showed the preferable example of the manufacturing method of the nonwoven fabric which concerns on this invention, (a) is principal part sectional drawing which showed the state which sprayed the 1st hot air, (b) is 1st It is principal part sectional drawing which showed after blowing hot air, (c) is principal part sectional drawing which showed the state which sprayed the 2nd hot air. It is the partially cutaway perspective view which showed typically the disposable diaper as one preferable embodiment of the absorbent article using the surface sheet which concerns on this invention.

Detailed Description of the Invention

The present invention has a high cushioning property when a nonwoven fabric is used as a top sheet of an absorbent article, and reduces the amount of liquid return in a large amount of excretion under high load and prevents leakage due to liquid flow on the surface. The present invention relates to a method for producing a compatible nonwoven fabric and a nonwoven fabric.

A preferred embodiment of the nonwoven fabric according to the present invention will be described below with reference to FIGS. 1 and 2.
The nonwoven fabric 10 of the present invention is preferably applied to a top sheet of absorbent articles such as sanitary napkins, disposable diapers, and incontinence pads. At that time, the nonwoven fabric 10 is preferably used with the first surface side Z1 facing the wearer's skin surface side. And it is preferable that the nonwoven fabric 10 uses the 2nd surface side Z2 arrange | positioning at the absorber (not shown) side inside an article | item. Hereinafter, an embodiment in which the first surface side Z1 of the nonwoven fabric 10 shown in the drawings is used toward the skin surface of the wearer will be described. The present invention is not construed as being limited thereby. In the plane arrangement diagram of FIG. 2, the upper side of the nonwoven fabric 10 is defined as the first surface side Z1 and the lower side of the nonwoven fabric 10 is defined as the second surface side Z2 in the z-axis of the orthogonal coordinate system.

As shown in FIG. 1 and FIG. 2, the nonwoven fabric 10 of the present invention has a continuous uneven curved surface, and forms a seamless sheet surface. That is, it protrudes to the 1st surface side Z1 on the side which planarly viewed the nonwoven fabric of the sheet body, and protrudes to the 2nd surface side Z2 on the opposite side to the 1st surface part Z1 and the 1st surface side Z1. And a second protrusion 12 having an internal space 12K. For example, the first protrusion 11 and the second protrusion 12 are different directions that intersect in plan view over the entire surface of the nonwoven fabric 10 in the first direction X and the second direction Y, respectively, in a plane parallel to the xy plane of the orthogonal coordinate system. They are arranged alternately and continuously. In the present embodiment, the first direction X and the second direction Y are orthogonal. Accordingly, the first direction X can be a direction parallel to the x-axis of the orthogonal coordinate system, and the second direction Y can be a direction parallel to the y-axis of the orthogonal coordinate system. Note that the first direction X and the second direction Y do not have to be orthogonal. For example, it is preferable that the first direction X and the second direction Y intersect within a range of about 60 ° to 120 °.
The convex portion viewed from the first surface side Z 1 is the first projecting portion 11, and the concave portion is the second projecting portion 12. Further, the convex portion viewed from the second surface side Z 2 is the second projecting portion 12, and the concave portion is the first projecting portion 11. Therefore, the first protrusion 11 and the second protrusion 12 are partially shared.

There is no clear boundary between the first protrusion 11 and the second protrusion 12. In this specification, it defines as follows on the basis of the space which each has the internal space 12K of the 1st protrusion part 11 and the 2nd protrusion part 12. FIG. That is, the 1st protrusion part 11 is the part protruded to the 1st surface side Z1 of the nonwoven fabric 10 of the 1st surface side Z1 which covers the internal space 11K and this. The part which protruded to the 1st surface side Z1 of the nonwoven fabric 10 is a part which connected from the 1st protrusion part top part 11T to the bottom part of the surrounding internal space 12K through the wall part 13 (14). Moreover, the 2nd protrusion part 12 containing the internal space 12K is a part which protruded to the 2nd surface side Z2 of the nonwoven fabric 10 of the 2nd surface side Z2 which covers the internal space 12K and this. The portion recessed in the second surface side Z2 of the nonwoven fabric 10 is a portion connecting the bottom portion of the internal space 12K to the surrounding first protruding portion top portion 11T through the wall portion 13 (14). The first protrusion 11 and the second protrusion 12 are shared between the first protrusion 11T and the bottom of the internal space 12K. The wall portion 13 (14) partitions the two internal spaces 11K and the internal space 12K.
Furthermore, in order to clarify the 1st protrusion part 11, the 2nd protrusion part 12, and the wall part 13, the height of the thickness direction of the nonwoven fabric 10 is divided into 3 equal parts, the upper part is the 1st protrusion part 11, and the intermediate part is a wall. The part 13 (14) and the lower part are defined as the second projecting part 12. Further, the ridge portion 15 is a portion connecting the highest positions in the first surface side Z1 direction in which the adjacent first projecting portions 11 are continuous. Furthermore, when it sees with the 1st protrusion part 11 and the ridge part 15, the lower part which equally divided the 1st protrusion part top part 11T and the lowest position of the ridge part 15 into the 1st surface side Z1 direction is made into the ridge part 15. .

The adjacent first protrusions 11 are continuously connected in an oblique direction with respect to the first direction X and the second direction Y via the ridge 15. In other words, the first projecting portion 11 is connected to the first direction X and the second direction Y in an oblique direction like a mountain range via the ridge portion 15. When the first direction X and the second direction Y are orthogonal to each other, the oblique direction is, for example, a 45 ° oblique direction with respect to each direction. Further, the adjacent second projecting portions 12 are continuous in the oblique direction with respect to the first direction X and the second direction Y through the ridge portion 15 as viewed from the second surface side Z2, similarly to the first projecting portion 11. Are connected.

The height h1 in the thickness direction of the first protruding portion 11 is higher than the height h5 in the thickness direction of the ridge portion 15 (see also FIG. 3). Each of the heights h1 and h5 represents a height in a direction perpendicular to the plane S including the apex of the second protrusion top 12. The height h1 represents the height of the first surface side Z1 of the first protrusion top 11T. The height h 5 represents the height of the first surface side Z 1 of the lowest portion of the ridge portion 15 between the first protrusions 11. Since the height h1 in the thickness direction of the first protruding portion 11 is higher than the height h5 of the ridge portion 15 in this way, the liquid is poured into the internal space 12K of the second protruding portion 12 that is surrounded on all sides by the first protruding portion 11. Accumulated, the liquid flows over the ridge 15 in the direction of the internal space 12K of the adjacent second protrusion 12. In this case, the liquid also flows below the ridge 15. However, no liquid leaks to the first surface side Z1. In addition, also in FIG. 3, the 1st surface side Z1 shows a wearer's skin surface side, and the 2nd surface side Z2 shows a non-skin surface side.

Moreover, the hydrophilicity of the 1st protrusion part top part 11T is lower than the part except the 1st protrusion part top part 11T in both surfaces of the 1st surface side Z1 and the 2nd surface side Z2. Or the 1st protrusion part top part 11T has hydrophobicity. That is, the hydrophilicity of the first protruding portion top portion 11T is lower than that of the second protruding portion top portion 12T and the wall portion 13. In other words, the first protrusion top 11T is more hydrophobic than the second protrusion top 12T and the wall 13 (14). Thereby, when the nonwoven fabric 10 is used as a surface sheet, the remaining amount of the liquid that touches the skin is reduced on the first surface side Z1 that is the skin contact surface side. In addition, the first surface side Z1 has a smaller hydrophobic area than the second surface side Z2 of the first protrusion top portion 11T. This makes it difficult for the overflowing liquid from the absorber (not shown) to return to the first surface side Z1 under high pressure such that the wearer is sleeping. Therefore, the liquid which returns to the 1st surface side Z1 used as the skin surface side is suppressed and reduces.
The level of hydrophilicity and the level of hydrophobicity are determined by measuring the contact angle described later. The smaller the contact angle value described later, the higher the hydrophilicity. The larger the contact angle value, the higher the hydrophobicity. In the present application, even in a region that is considered to be hydrophobic, the level of hydrophilicity is compared and judged by the magnitude of the contact angle value described later.
In addition, even if the 1st protrusion part top part 11T is not hydrophobized, the nonwoven fabric 10 has an effect of this invention fundamentally. That is, the nonwoven fabric 10 can have a high cushioning property, can maintain an uneven shape even under a high load, and further suppress the increase in the contact area with the skin and suppress the adhesion of discharged liquid to the skin. Can do. As described above, it is more preferable that the first projecting portion top portion 11T is hydrophobized because adhesion of the discharged liquid to the skin can be further suppressed.

As shown in FIG. 4, the fibers 16 constituting the wall portion 13 have fiber orientation in the direction indicated by the arrow A connecting the first protruding portion top portion 11T and the edge portion of the opening portion 11H of the internal space 11K. In other words, it has fiber orientation in the direction in which the wall portion 13 stands. Therefore, it has the radial fiber orientation which goes to the 1st protrusion part top part 11T. In addition, the direction which ties the 1st protrusion part top part 11T and the edge part of the opening part 11H of the internal space 11K, and the direction where the wall part 13 stands up substantially correspond with the thickness direction in a nonwoven fabric.
Moreover, as shown in FIG. 5, the fiber 16 which comprises the wall part 14 (13) of the 2nd protrusion part 12 is the arrow A which connects the edge part of the opening part 12H of the 2nd protrusion part top part 12T and its internal space 12K. It has fiber orientation in the direction indicated by. The fiber orientation of the wall portion 14 is the same as the fiber orientation of the wall portion 13 in the common portion with the wall portion 13 described above. Note that the direction connecting the second projecting portion top 12T and the edge of the opening 12H of the internal space 12K and the direction in which the wall 13 rises substantially coincide with the thickness direction of the nonwoven fabric.

Thus, the wall 13 of the first protrusion 11 has fiber orientation in the direction connecting the top 11T of the first protrusion 11 and the opening 11H of the internal space 11K of the first protrusion 11. From this, the 1st protrusion part 11 and the 2nd protrusion part 12 are hard to be crushed even under the high pressurization where a wearer is sleeping. In addition, this configuration provides excellent shape retention, high air permeability, and solves the problem of stuffiness. Furthermore, a firm stiffness is born in the wall portion 13 by the above configuration. For this reason, it also has moderate cushioning properties in which the fibers are not crushed in the thickness direction. Furthermore, even if the nonwoven fabric 10 is crushed due to the pressing force due to the fiber orientation of the wall portion 13, the shape restoring force is large, and the initial cushioning force is easily maintained even if the packing state and wearing are continued. That is, the shape retention of the nonwoven fabric 10 is excellent even with the seating pressure of the wearer. In addition, the contact area between the nonwoven fabric 10 and the skin is kept small even at high pressure. For this reason, the first and second protrusions are not easily crushed and can be easily recovered even if deformation occurs.
By the fibers oriented in the thickness direction of the wall portion 13, the liquid flows along the fibers smoothly. And a liquid transfers to the absorber (not shown) distribute | arranged to the lower surface of the nonwoven fabric 10. FIG. In addition, since the return of liquid is reduced by the fiber orientation of the wall portion 13, a smooth touch is realized. Moreover, it is useful for prevention of a blurring by being excellent in the air permeability of nonwoven fabric 10 itself by maintenance of the structure mentioned above.

When the nonwoven fabric 10 is pressurized at a pressure of 3.5 kPa, the height h1 in the thickness direction of the first protrusion 11 is higher than the height h5 of the ridge 15. As a result, the flow of the liquid on the first surface side Z1 of the nonwoven fabric 10 is oblique to the first direction X parallel to the x direction of the orthogonal coordinate system and the second direction Y parallel to the y direction of the orthogonal coordinate system. The liquid begins to flow. That is, when the nonwoven fabric 10 is used as the top sheet of the absorbent article and the first direction X is used as the width direction of the absorbent article, the liquid flows in an oblique direction with respect to the width direction of the absorbent article. Thereby, the liquid overflowing the internal space 12K of the second projecting portion 12 easily flows into the internal space 12K of the adjacent second projecting portion 12 via the ridge portion 15 over the ridge portion 15. For this reason, the distance until the liquid leaks in the lateral direction becomes longer, and the liquid is easily absorbed during that time. This makes it difficult for the liquid to leak sideways.
The ratio (h1 / h5) between the height h1 of the first protrusion 11 in the thickness direction and the height h5 of the ridge 15 when the nonwoven fabric 10 is pressurized at a pressure of 3.5 kPa is a side leakage. From the viewpoint of difficulty, it is preferably 1.01 or more, more preferably 1.05 or more, and further preferably 1.2 or more. Moreover, as an upper limit, it is preferable that it is 2.5 or less, It is more preferable that it is 2.0 or less, It is further more preferable that it is 1.8 or less.
The reason why the nonwoven fabric 10 is measured by pressurizing at a pressure of 3.5 kPa is that it simulates the pressure applied to the nonwoven fabric when the wearer is seated. That is, the seating pressure is assumed to be 3.5 kPa. A wearer is a wearer of the baby diaper which is the main focus in this specification, that is, an infant.
Moreover, the pressure concerning a nonwoven fabric when a wearer is standing is measured as follows in the meaning which contrasts with the pressure concerning a nonwoven fabric when the wearer is sitting. When the wearer is standing, the load applied to the nonwoven fabric is basically assumed to be no load. However, when the nonwoven fabric is measured without applying a load, the measurement values vary due to the characteristics of the nonwoven fabric, which is an aggregate of fibers. For this reason, measurement is carried out by imitating measurement with substantially no pressure while suppressing variations in measured values, that is, with a load of about 0.05 kPa as a state close to no pressure.

Further, the first protrusion 11 has a height h1 (see FIG. 3), and the rising angle of the wall is steeper and the top is round like a part of the hemisphere, rather than a cone having a round top like a hemisphere. It is more preferable that the truncated cone has. The rising angle α of the wall portion 13 of the first projecting portion 11 is not less than 0 ° and not more than 20 °, preferably greater than 0 ° and not more than 20 °, more preferably not less than 0 ° and not more than 15 °. Is more preferable, and it is further more preferable that it is larger than 0 degree and 12 degrees or less. The rising angle α is obtained by a measurement method described later. If the rising angle α is too large, the nonwoven fabric tends to collapse in the thickness direction. For this reason, the cushioning effect of a nonwoven fabric falls and the amount of liquid return increases. Furthermore, since the skin contact area at the time of high pressurization becomes large, it becomes difficult to give a wearer a gentle touch to the skin.

In the present embodiment, the first projecting portion 11 and the second projecting portion 12 have a truncated cone shape or a hemisphere with rounded

top portions

11T and 12T. If it sees in detail, the protrusion shape of the 1st protrusion part 11 is a shape close | similar to a truncated cone shape. On the other hand, the projecting shape of the second projecting portion 12 is a cone or truncated cone shape with a rounded top. In addition, in this embodiment, the 1st,

2nd protrusion parts

11 and 12 are not limited to the said shape. Therefore, any protruding form may be used. For example, it is practical to have various cone shapes. In the present specification, the term “conical shape” means that a cone, a truncated cone, a pyramid, a truncated pyramid, an oblique cone, and the like are included. In this embodiment, the 1st protrusion part 11 is holding | maintaining the internal space 11K of the truncated cone shape with the roundness in the top part similar to the outer diameter. Moreover, the 2nd protrusion part 12 hold | maintains the truncated cone shape or hemispherical internal space 12K with the roundness in the top part similar to the outer diameter.

A wall 13 is provided between the top of the first protrusion 11 (hereinafter also referred to as the first protrusion 11) 11T and the opening 11H. The wall portion 13 forms an annular structure in the first projecting portion 11. Moreover, it has the wall part 14 between the top part (henceforth the 2nd protrusion part top part) 12T of the 2nd protrusion part 12, and its opening part 12H. The wall portion 14 forms an annular structure in the second projecting portion 12. The wall portion 14 is shared with the wall portion 13 in part. The “annular” here is not particularly limited as long as it has an endless series of shapes in plan view. For example, the “annular” may be any shape such as a circle, an ellipse, a rectangle, or a polygon in plan view. In order to suitably maintain the continuous state of the sheet, the “annular” is preferably a circle or an ellipse. Furthermore, “annular” is a three-dimensional shape: cylinder, oblique cylinder, elliptical cylinder, truncated cone (truncated cone), oblique truncated cone (truncated truncated cone), oblique elliptical truncated cone (truncated elliptical cone), four Arbitrary ring structures composed of side surfaces such as a truncated pyramid (truncated quadrangular pyramid) and an oblique quadrangular pyramid (truncated oblique pyramid) can be mentioned. In order to realize a continuous sheet state, a cylinder, an elliptic cylinder, a truncated cone, and an elliptic truncated cone are preferable.

The nonwoven fabric 10 having the first and second projecting

portions

11 and 12 arranged as described above does not have a bent portion. That is, the nonwoven fabric 10 is formed of a curved surface that is continuous throughout. The said bending part means the part which a surface bends and has a corner | angular part.
Thus, it is preferable that the said nonwoven fabric 10 has a structure continuous in the surface direction. This “continuous” means that there are no intermittent portions or small holes. However, fine holes such as gaps between fibers are not included in the small holes. The small hole can be defined, for example, as a hole having a diameter equivalent to a circle of 1.0 mm or more.

The fiber material that can be used for the nonwoven fabric 10 of the present invention is not particularly limited. Specific examples of the fiber material include the following fibers. There is a fiber made of a thermoplastic resin such as a polyolefin resin such as polyethylene (PE) or polypropylene (PP), a polyester resin such as polyethylene terephthalate (PET), or a polyamide-forming resin. Specific examples of the fiber material include composite fibers having a structure such as a core-sheath type and a side-by-side type. In the present invention, it is preferable to use a composite fiber as the fiber material. Examples of the composite fiber include a core-sheath fiber having a high melting point component as a core portion and a low melting point component as a sheath portion, and a side-by-side fiber in which a high melting point component and a low melting point component are arranged in parallel. Preferable examples thereof include fibers having a core-sheath structure in which the sheath component (low melting point component) is polyethylene or low melting point polypropylene. Representative examples of the core-sheath fiber include PET (core) and PE (sheath), PP (core) and PE (sheath), polylactic acid (core) and PE (sheath), PP (core) and low melting point PP. Examples thereof include fibers having a core-sheath structure such as (sheath). More specifically, the constituent fibers preferably include polyolefin fibers such as polyethylene fibers and polypropylene fibers, polyethylene composite fibers, and polypropylene composite fibers. Here, the composite composition of the polyethylene composite fiber is polyethylene terephthalate and polyethylene. The composite composition of the polypropylene composite fiber is preferably polyethylene terephthalate and low melting point polypropylene. More specifically, examples of the composite composition of the polypropylene composite fiber include PET (core) and PE (sheath), and PET (core) and low melting point PP (sheath). Moreover, these fibers may be used alone to constitute a nonwoven fabric, or may be used as a mixed fiber in which two or more kinds are combined.

Next, the dimension specification in the nonwoven fabric 10 of this embodiment is demonstrated below.
As shown in FIG. 6, about the thickness of a sheet | seat, let the whole thickness when the nonwoven fabric 10 is seen from a side view be sheet thickness TS. The thickness of the local cross section of the sheet curved by the unevenness of the nonwoven fabric 10 is defined as a layer thickness TL. The sheet thickness TS may be appropriately adjusted depending on the application. When used as a top sheet for diapers, sanitary products, etc., 1 mm or more and 7 mm or less is preferable, and 1.5 mm or more and 5 mm or less is more preferable. By setting it as the range, the body fluid absorption speed at the time of use is high, the liquid return from an absorber is suppressed, and also moderate cushioning property is realizable. The layer thickness TL may be different at each site in the sheet. Further, the layer thickness TL may be adjusted as appropriate depending on the application. When used as a surface sheet for diapers, sanitary products, etc., the layer thickness TL1 of the first protrusion top 11T is preferably 0.1 mm or more and 3 mm or less, and more preferably 0.4 mm or more and 2 mm or less. The preferable range of the layer thickness is the same for the layer thickness TL2 of the second protrusion top 12T and the layer thickness TL3 of the wall 13. The relationship between the layer thicknesses TL1, TL2, and TL3 is preferably TL1>TL3> TL2. Thereby, in the 1st protrusion part 11, a fiber density becomes low especially in the skin surface side. Moreover, in the 1st protrusion part 11, favorable skin contact is realizable especially in the skin surface side. On the other hand, the 2nd protrusion part 12 becomes high in fiber density, is not crushed easily, and does not lose shape. For this reason, it becomes a nonwoven fabric excellent in favorable cushioning properties and liquid absorption speed.
As shown in FIG. 7, the distance Dx when the first protrusion top 11T and the second protrusion top 12T in the first direction X are projected onto a plane may be adjusted as appropriate according to the application. When used as a surface sheet for diapers, sanitary products, etc., it is preferably 1 mm or more and 15 mm or less, more preferably 3 mm or more and 10 mm or less. Further, as indicated by the reference numerals in the parentheses in the drawing, the distance Dy when the first protrusion top 11T and the second protrusion top 12T in the second direction Y are projected onto a plane is the same as the distance Dx in the first direction X. . Moreover, the basic weight of the said nonwoven fabric 10 is not specifically limited. The average value of the entire sheet is preferably 15 g / m ² or more and 50 g / m ² or less, more preferably 20 g / m ² or more and 40 g / m ² or less.

The nonwoven fabric 10 demonstrated by the said embodiment has the following effects.
The nonwoven fabric 10 is a case where a large amount of liquid is excreted, and when the load is high, the liquid remaining amount and the liquid return amount are reduced. Therefore, the liquid flow on the surface can be suppressed so that the liquid does not leak. Thereby, both prevention of the liquid flow on a skin contact surface and prevention of the liquid return from the non-skin contact surface side can be aimed at.

Furthermore, due to a series of first projecting portion top portions 11T that are connected via the ridge portion 15, on the non-skin contact surface side of the nonwoven fabric, a space due to a sequence of the internal spaces 11K of the first projecting portions 11 is continued in two directions. For this reason, even if solid content, a highly viscous liquid, or the like is supplied, higher air permeability can be obtained depending on the space. Further, when a large amount of liquid is supplied, the captured large amount of liquid can be diffused in the continuous direction of the space. And the liquid leakage to a horizontal direction can be prevented by the connection of the 1st protrusion part 11. FIG.

The said nonwoven fabric 10 is excellent in the excretion capture | acquisition property.
In the nonwoven fabric 10 of this embodiment, it has

internal space

11K, 12K inside each of the 1st,

2nd protrusion parts

11 and 12 which protrude on both surfaces. Therefore, these can be captured and dealt with in various forms according to the physical properties of the excretory fluid and excrement. For example, the 1st surface side Z1 of the nonwoven fabric 10 is demonstrated as a skin surface side. If the excretory liquid has a low viscosity and easily permeates, it passes through the top sheet of the nonwoven fabric 10 and is then captured in the internal space 11K. The portion that first hits the skin surface is the first protrusion top 11T, and the captured excretory fluid or excrement is made difficult to contact the skin. As a result, a very good and smooth feeling is maintained in response to excretion of urine, menstrual blood, and fallen goods.

Next, a preferred embodiment of the method for producing the nonwoven fabric 10 will be described below with reference to FIG.
The following manufacturing method should just be employ | adopted for the manufacturing method of the above-mentioned nonwoven fabric 10 suitably.

As an example of the support, the support 110 having the configuration shown in FIG. The support 110 has a large number of protrusions 111 corresponding to positions where the second protrusions 12 are shaped. Moreover, the hole 112 is arranged corresponding to the position where the 1st protrusion part 11 is shaped. That is, the support body 110 has an uneven shape. The protrusions 111 and the holes 112 are alternately arranged in different directions. For example, the protrusions 111 and the holes 112 are alternately arranged in the first direction X and the second direction Y, respectively.
Moreover, the support body 110 is heated.
As a method for heating the support 110, heat is transferred to the support 110 itself to heat it. That is, this is a method of directly heating the support 110 with a heat source (not shown). For example, a heater provided with a heating wire may be provided on the back side of the support 110 on which the protrusions 111 are not provided. Alternatively, the support 110 may be warmed by blowing hot air before the web 50 is conveyed onto the support 110. When the first hot air W1 is finally blown, any heating means may be used as long as the temperature of the support 110 is within an appropriate temperature range.
The temperature which heats the support body 110 shall be temperature more than the glass transition point of the fiber which comprises a web, and below melting | fusing point. By setting the support 110 to a temperature equal to or higher than the glass transition point of the fiber, the web 50 is easily plastically deformed. Therefore, it is considered that the shape along the support 110 is likely to be obtained. That is, it becomes easy to shape the web 50 along the shape of the support 110. On the other hand, if the heating of the support 110 is too low, the difference between the height of the first protrusion 11 and the height of the ridge 15 is reduced. In this case, the rising angle of the wall portion does not become steep. If the first projecting portion top portion 11T is hydrophobized in this state, a large amount of liquid is excreted on the nonwoven fabric surface when a high load is applied to the nonwoven fabric 10 (a weight of about the seating pressure). And it becomes easy to raise | generate the leakage of the liquid along the nonwoven fabric surface. On the other hand, if the heating is too low, the concavo-convex shape tends to be crushed regardless of the hydrophobicity. Therefore, it is not preferable. On the other hand, if the heating of the support 110 is too high, the fibers are fused together and cannot be shaped.
The temperature of the supporting body 110 is preferably set to the above temperature range when the first hot air W1 described in the next step is blown.

A web 50 (also referred to as a fiber web) obtained by hydrophilizing hydrophobic thermoplastic fibers with a hydrophilizing oil is used. A known method can be used for the hydrophilic treatment. The web 50 is disposed on the support 110, and the first hot air W1 is blown toward the web 50. Then, as shown in FIG. 8B, the first protrusion 11 is shaped corresponding to the hole 112 of the support 110, and the second protrusion 12 is shaped corresponding to the position of the protrusion 111. The Therefore, the 1st protrusion part 11 protrudes in the 1st surface side Z1 of the side seen by plane, and has the internal space 11K. The 2nd protrusion part 12 protrudes in the 2nd surface side Z2, and has internal space 12K. The first protrusions 11 and the second protrusions 12 are alternately and continuously arranged in different first directions X and second directions Y that intersect in plan view. In this way, the web 50 is shaped.
At that time, as the height h1 in the thickness direction of the first protrusion 11 (see FIG. 3), the first protrusion 11 has a steeper rising angle of the wall than a cone whose top is round like a hemisphere, The top is a truncated cone having a rounded shape like a part of a hemisphere. The rising angle α of the wall portion 13 of the first projecting portion 11 is preferably set as described above.
The arrows in the drawing schematically show the flow of the first hot air W1.

Specific examples of this production method include the following embodiments.
The web 50 before being fused is supplied from a card machine (not shown) to a device for shaping the web so as to have a predetermined thickness. As shown in FIG. 8A, in the shaping apparatus, first, the web 50 is conveyed and fixed on the support 110 heated to the above temperature.
The heating temperature of the support 110 is a temperature not lower than the glass transition point of the fiber to be shaped and not higher than the melting point, preferably higher than the glass transition point of the fiber and not higher than 10 ° C. below the melting point. Preferably, the temperature is 20 ° C. higher than the glass transition point of the fiber and 20 ° C. lower than the melting point. For example, when using a composite fiber as the thermoplastic fiber, the glass transition point of the high glass transition point component is not lower than the glass transition point of the high glass transition point component and not more than 10 ° C. lower than the melting point of the low melting point component. The temperature is 20 ° C. or higher and 20 ° C. or lower than the melting point of the low melting point component. For example, when fiber having a core / sheath structure of PET (core) having a glass transition point of 67 ° C. and a melting point of 258 ° C./PE (sheath) having a glass transition point of −20 ° C. and a melting point of 135 ° C. is used as the fiber. It is preferable to heat at a temperature of not lower than 125 ° C and not higher than 125 ° C. Moreover, in the example of the same fiber, it is more preferable to heat at 87 degreeC or more and 115 degrees C or less. If this heating temperature is too low, shaping along the shape of the support 110 becomes impossible. As a result, the difference in height between the first protrusion 11 and the ridge 15 (see FIGS. 1 and 2) does not increase. For this reason, when the amount of the liquid flowing on the surface of the nonwoven fabric 10 under a high load becomes large, leakage easily occurs. On the other hand, if the heating temperature of the support 110 is too high, fusion between fibers occurs, or fusion to the support 110 occurs, and the desired shape cannot be formed.

Next, the first hot air W1 is blown onto the web 50 on the support 110 (the state shown in FIG. 8A). Then, the web 50 is shaped so as to follow the shape of the support 110 (the state shown in FIG. 8B). The temperature of the first hot air W1 at this time is preferably 0 ° C. to 70 ° C. lower than the melting point of the thermoplastic fiber constituting the web 50 in consideration of a general fiber material used for this type of product. More preferably, the temperature is 5 to 50 ° C lower. The wind speed of the first hot air W1 is set to 20 m / s or more and 150 m / s or less, preferably 30 m / s or more and 100 m / s depending on the height of the protrusions 111 of the support 110, from the viewpoint of shaping and texture. It is as follows. When the wind speed is slower than this lower limit, the nonwoven fabric is not sufficiently shaped. For this reason, the cushioning property of a nonwoven fabric, the stock property of excrement, and the effect of air permeability are not fully exhibited. When the wind speed exceeds this upper limit value, an opening is generated in the top portion 22T of the second protrusion 22. In this case, the nonwoven fabric tends to be crushed, and the cushioning property, excrement stock property, and air permeability effect are not sufficiently exhibited. Furthermore, it becomes easy for excrement to go back through the opening.
In this way, the web 50 is shaped into a concavo-convex sheet.

In addition, the height of the protrusion 111 of the support 110 is appropriately determined depending on the thickness of the entire sheet to be shaped and the layer thickness of the sheet. For example, it is set to 1 mm or more and 10 mm or less, preferably 1.5 mm or more and 9 mm or less, more preferably 2 mm or more and 8 mm or less.

Next, as shown in FIG. 8C, the second hot air W2 at a temperature at which each fiber of the web 50 can be appropriately fused is blown to fuse and fix the fibers together. The temperature of the second hot air W2 at this time is preferably 0 ° C. to 70 ° C. higher than the melting point of the thermoplastic fiber constituting the web 50 in consideration of a general fiber material used for this type of product. More preferably, the temperature is 5 to 50 ° C higher. The wind speed of the second hot air W2 is set to 1 m / s or more and 10 m / s or less, preferably 3 m / s or more and 8 m / s or less. If the wind speed of the second hot air W2 is too slow, heat cannot be transferred to the fibers. For this reason, the fibers are not fused with each other, and the fixing of the uneven shape becomes insufficient. On the other hand, if the wind speed is too high, too much heat is applied to the fibers. Thereby, it becomes the tendency for the texture of a nonwoven fabric to worsen.

As the thermoplastic fiber, the fiber described above is used. For example, when a composite fiber containing a low melting point component and a high melting point component is used as the thermoplastic fiber, the temperature of the second hot air W2 sprayed on the web 50 is equal to or higher than the melting point of the low melting point component and lower than the melting point of the high melting point component. It is preferable. More preferably, the temperature is at least 10 ° C lower than the melting point of the high melting point component, more preferably at least 5 ° C higher than the melting point of the low melting point component, and more preferably at least 20 ° C lower than the melting point of the high melting point component. .

The web 50 preferably contains 30% by mass or more and 100% by mass or less of thermoplastic fiber, more preferably 40% by mass or more and 100% by mass or less. The web 50 may include fibers that do not inherently have heat-fusibility. Examples of fibers that do not have heat-fusibility include natural fibers such as cotton and pulp, rayon, and acetate.

Next, the hydrophobization of the first protrusion top 11T will be described.
The nonwoven fabric 10 basically exhibits the effects of the present invention even if the first protrusion top 11T is not hydrophobized. That is, it becomes easy to shape the web, the nonwoven fabric can have high cushioning properties, and the uneven shape can be maintained even under high load. Furthermore, since the contact area of a nonwoven fabric and skin is not increased and adhesion of the discharged liquid to skin can be suppressed, it is more preferable.
The hydrophobizing method is not particularly limited. For example, the hydrophobizing method includes gravure coating and screen coating.
Or it is also possible to employ | adopt the following methods.
A plate having a non-deformable flat coating surface to which a hydrophobic agent has been applied in advance is prepared. The nonwoven fabric 10 is disposed so that the application surface of the hydrophobic agent is in contact with the first protrusions 11 of the nonwoven fabric 10 evenly. Then, assuming the use state of the infant, a weight is placed on the plate so that a pressure of 0.5 kPa to 3.5 kPa is applied. Thereby, a constant pressure is applied to the first protrusion 11 of the nonwoven fabric 10. The hydrophobic agent applied to the application surface soaks into the first protruding portion top portion 11T that is in contact with the application surface with this pressure. And the hydrophobic part 11D is formed in the 1st protrusion part top part 11T (refer FIG. 1). By using a weight, it is possible to apply a load evenly to each first protrusion top 11T. Thus, the hydrophobic agent can be evenly transferred to each first protrusion top 11T. That is, the hydrophobic portion 11D can be formed with high accuracy. Then, the hydrophobic agent soaked into the first protrusion top portion 11T is diffused in all directions in the first protrusion top portion 11T. The pressure due to the weight can be appropriately adjusted so as to obtain a desired effect of suppressing the adhesion of the discharged liquid to the skin.
As described above, a hydrophobization treatment is performed by applying a pressure of 0.5 kPa or more and 3.5 kPa or less to the plate so that the hydrophobic agent is soaked into the first protrusion top portion 11T. Thereby, as shown in Examples 4 to 9 which will be described later, an effect of reducing the amount of liquid return can be obtained.
In the first projecting portion top portion 11T, the area St2 (not shown) on the second surface side Z2 of the hydrophobic portion 11D is made wider than the area St1 (not shown) on the first surface side Z1 of the hydrophobic portion 11D. For this purpose, there is a method in which a hydrophobic agent is injected into the first protrusion top 11T from a nozzle (not shown). Specifically, there is a method of increasing the injection depth of the nozzle and injecting from the vicinity of the second surface side Z2 side. For the hydrophobic agent, for example, a hydrophobic oil agent is used. By changing the injection depth of the nozzle, the area ratio between the area St1 on the first surface side Z1 of the hydrophobic portion 11D and the area St2 on the second surface side Z2 of the hydrophobic portion 11D can be changed. Further, the fineness of the second surface side Z2 of the thermoplastic fiber used for the web 50 is made smaller than the fineness of the first surface side Z1. In this way, the fiber density on the second surface side Z2 is made higher than the fiber density on the first surface side Z1. This also makes it possible to achieve the change in the area ratio. This is because the hydrophobic agent soaked into the first protrusion top 11T diffuses more on the second surface side Z2 than on the first surface side Z1. Furthermore, the hydrophobic area of the hydrophobic portion 11D is preferably adjusted so that the amount of liquid return is effectively reduced in the usage state.

Various kinds of known hydrophilic agents can be used for the hydrophilic treatment without particular limitation. For example, a hydrophilic oil agent is used. As the hydrophilic oil agent, an anionic, cationic, amphoteric or nonionic surfactant is generally used. In particular, it is not limited to these. These can be used as an aqueous solution or an emulsion having a predetermined concentration. Preferred hydrophilizing agents include aliphatic monocarboxylate, polyoxyethylene alkyl sulfate, polyoxyethylene alkyl phosphate, glycerin fatty acid ester, sorbitan fatty acid ester, sucrose fatty acid ester, polyoxyethylene alkyl ether, fatty acid polyethylene Examples include glycols, alkylamine salts, and alkylbetaines.

Specific examples of the hydrophobic agent include silicone oligomers and fluorine oligomers. The silicone oligomer is typically a chain polydimethylsilicone. Further, there are modified silicones in which a part of the methyl group is replaced with a polyether, phenyl group or trifluoropropyl group. As the fluorine oligomer, an acrylic acid ester or a phosphoric acid ester of alcohol containing a perfluoroalkyl group as a water and oil repellent agent is used. The feature of the silicone water repellent is that it has excellent water repellency and flexibility and is suitable for the treatment of a surface agent that directly contacts the skin. A fluorine-based water repellent exhibits the most excellent water repellency. In particular, there is an advantage that water repellency can be maintained even when a surfactant for hydrophilicity is in contact.

The nonwoven fabric 10 is produced as described above.
The manufacturing method considers continuous production. The manufacturing apparatus (not shown) includes a conveyor type or a drum type capable of transporting the support 110. As an example, a mode in which the conveyed sheet with the uneven shape fixed thereon is wound up by a roll (not shown).

In the manufacturing method, the thickness of each sheet is appropriately determined according to the wind speed of the first hot air W1. For example, when the wind speed is increased, the thickness of the sheet increases. If it is delayed, the thickness of the sheet becomes thinner. Further, when the wind speed is increased, the fiber density difference between the first protrusion and the second protrusion is increased. When the wind speed is decreased, the fiber density difference between the first protrusion and the second protrusion is reduced.

The nonwoven fabric 10 of the present invention can be used for various applications. For example, it can be suitably used as a surface sheet for absorbent articles such as disposable diapers, sanitary napkins, panty liners, urine absorption pads and the like. Furthermore, the non-woven fabric 10 is excellent in air permeability, liquid diffusibility, deformation characteristics at the time of pressing force, etc. due to the uneven structure on both sides. From this, it can also be used as a sub-layer interposed between a surface sheet such as a diaper or sanitary product and an absorbent body. In addition, the form utilized as a gather of an absorbent article, an exterior sheet, and a wing is also mentioned. Furthermore, the form utilized as a wiping wipe sheet | seat, a cleaning sheet | seat, and a filter is also mentioned.

Next, a preferred embodiment of an absorbent article using the nonwoven fabric according to the present invention for the top sheet will be described with reference to FIG. As an embodiment, an application example of the disposable diaper 100 to the main body 4 will be described. The disposable diaper shown in the figure is a tape-type disposable diaper for infants. The drawing shows a state in which the diaper in a flat state is bent slightly and viewed from the inside (skin contact surface side).

As shown in FIG. 9, the disposable diaper 100 includes a liquid permeable top sheet 1 disposed on the skin contact surface side, a liquid poorly permeable back sheet 2 disposed on the non-skin contact surface side, and the above-mentioned A liquid-retaining absorbent 3 is disposed between both sheets.
The nonwoven fabric 10 of the above embodiment is applied to the top sheet 1. The 1st protrusion part 11 side of the nonwoven fabric 10 is made into the skin contact surface.

The back sheet 2 has a shape in which both side edges are bound inward in the longitudinal center C in the unfolded state. And back sheet 2 may consist of one sheet, or may consist of a plurality of sheets.
The back sheet 2 is not particularly limited as long as it has waterproofness and moisture permeability. For example, a porous film is mentioned. The porous film is formed by melting and kneading a hydrophobic thermoplastic resin, a fine inorganic filler made of calcium carbonate or the like, an incompatible organic polymer, or the like. The film is obtained by uniaxial or biaxial stretching. Examples of the thermoplastic resin include polyolefin. Examples of the polyolefin include high density to low density polyethylene, linear low density polyethylene, polypropylene, polybutene and the like. And these thermoplastic resins can be used individually or in mixture.

As the absorbent body 3, various forms used for this type of article can be widely adopted as long as they have liquid retention. For example, there exists what coated the pulp fiber with the core wrap sheet as an absorber. There exists a sheet-like thing using the airlaid nonwoven fabric as an absorber. There exists a sheet-like thing formed by sandwiching a superabsorbent polymer with a fiber sheet as an absorber. There are various ways like this. Examples of the pulp fiber include wood pulp such as softwood kraft pulp and hardwood kraft pulp. Or as a pulp fiber, natural cellulose fibers, such as non-wood pulp, such as cotton pulp and a straw pulp, are mentioned. In addition, as a fiber used for an absorber, synthetic resin fibers, such as polyolefin resin, such as polyethylene and a polypropylene, polyester resins, such as a polyethylene terephthalate, and polyvinyl alcohol resin, are mentioned. Synthetic resin fibers include single fibers or composite fibers containing two or more of these resins. Alternatively, semi-synthetic fibers such as acetate and rayon may be included in a part of the absorber. In addition, as the superabsorbent polymer, various polymer materials usually used for this type of article can be used. The water-absorbing polymer is preferably a superabsorbent polymer compound having a performance capable of absorbing and retaining water or saline more than 20 times its own weight.
The covering sheet is a hydrophilic member. For example, as a covering sheet, thin paper (thin paper) such as hydrophilic tissue paper, crepe paper, non-woven fabric made of hydrophilic fibers such as cotton and rayon, non-woven fabric formed by subjecting synthetic resin fibers to hydrophilic treatment, Etc. As the nonwoven fabric, for example, an air-through nonwoven fabric, a point bond nonwoven fabric, a spunlace nonwoven fabric, a spunbond nonwoven fabric, a spunbond-meltblown-spunbond (SMS) nonwoven fabric, or the like can be used.

The side sheet 5 is preferably a water-repellent nonwoven fabric. For example, as the side sheet 5, a non-woven fabric, a spunbonded non-woven fabric, a melt blown non-woven fabric, a spunlace non-woven fabric, a heat roll non-woven fabric, a needle punched non-woven fabric manufactured by the card method can be used. Particularly preferred are spunbond nonwoven fabric, spunbond-meltblown (SM) nonwoven fabric, spunbond-meltblown-spunbond (SMS) nonwoven fabric, and the like.

In this example, a side leakage preventing gather 7 is provided on the side seat 5. As a result, it is possible to effectively prevent lateral leakage of liquid or the like in the hip joint portion due to the movement of the infant. The diaper of the present embodiment may be further provided with a functional structure, a sheet material, and the like. In addition, in FIG. 9, the arrangement | positioning relationship and boundary of each member are not illustrated strictly. If it is the general form of this kind of diaper, the structure will not be specifically limited.

The above diaper is shown as a tape type. A fastening tape 6 is provided on the flap portion on the back side R. Fastening tape 6 can be affixed to a tape affixing part (not shown) provided in the flap part of ventral side F, and a diaper can be mounted and fixed. At this time, the center part C of the diaper is gently bent inward so that the absorbent body 3 is worn along the baby's buttocks and lower abdomen. As a result, excreta is absorbed and held in the absorber 3 accurately. Diapers are used in such a wearing form. In particular, the nonwoven fabric 10 is applied as the top sheet 1. This prevents the flow of liquid on the skin contact surface and the return of liquid from the non-skin contact surface side even when a large amount of liquid is excreted or under high load. It is possible to achieve both prevention. Further, higher air permeability is obtained by the space formed by the continuous internal space 11K. Then, a large amount of the captured liquid can be diffused in the continuous direction of the space. Thereby, liquid leakage in the lateral direction can be prevented. Furthermore, the excreted fluid or excreted matter that is captured is made difficult to come into contact with the skin. As a result, even after excretion of urine, menstrual blood, descending products, etc., a very good and smooth feeling can be sustained in a wide range.

The absorbent article of the present invention is not limited to the disposable diaper of the above embodiment. For example, it can be applied to sanitary napkins, panty liners, incontinence pads, urine collection pads, and the like. In addition to the top sheet 1, the back sheet 2, and the absorbent body 3, members may be appropriately incorporated as constituent members of the absorbent article according to applications and functions.

This invention discloses the manufacturing method of the following nonwoven fabrics, the surface sheet for absorbent articles, an absorbent article, and a nonwoven fabric further regarding embodiment mentioned above.
<1> a first protrusion that protrudes toward the first surface of the sheet body in a plan view and has an internal space;
A second projecting portion projecting on the second surface side opposite to the first projecting portion and having an internal space;
A plurality of the first protrusions and the second protrusions are alternately and continuously arranged through wall portions in different directions intersecting in plan view of the nonwoven fabric,
The adjacent first protrusions and the adjacent second protrusions are nonwoven fabrics that are continuously connected in an oblique direction in plan view with respect to each of the different directions via the ridges, respectively.
When pressurizing the nonwoven fabric at a pressure of 0.05 kPa,
The height in the thickness direction of the first protrusion is higher than the height in the thickness direction of the ridge,
The nonwoven fabric whose rise angle of the wall part of the said 1st protrusion part is 0 degree or more and 20 degrees or less.
<2> The rising angle of the wall portion of the first protrusion is preferably greater than 0 ° and 20 ° or less, more preferably greater than 0 ° and 15 ° or less, and greater than 0 °. The nonwoven fabric according to <1>, more preferably 12 ° or less.
<3> The fibers constituting the wall have fiber orientation in a direction connecting the top of the first protrusion and the edge of the opening of the internal space of the first protrusion <1>. Or the nonwoven fabric as described in <2>.
<4> The nonwoven fabric according to any one of <1> to <3>, wherein the fiber constituting the wall portion has fiber orientation in a direction in which the wall portion stands.
The fiber which comprises the <5> said wall part is a nonwoven fabric any one of <1> to <4> which has radial fiber orientation which goes to the said 1st protrusion part top part.
<6> The fibers constituting the wall of the second protrusion have fiber orientation in the direction connecting the top of the second protrusion and the edge of the opening of the internal space. <1> to <5> The nonwoven fabric of any one.
<7> The nonwoven fabric according to any one of <1> to <6>, wherein the orientation angle of the wall portion is 50 ° to 130 °, and the orientation strength is 1.05 or more.
<8> The nonwoven fabric according to any one of <1> to <6>, wherein the wall has an orientation angle of 60 ° to 120 ° and an orientation strength of 1.10 or more.
<9> The nonwoven fabric according to any one of <1> to <6>, wherein the wall has an orientation angle of 85 ° to 95 ° and an orientation strength of 1.30 or more.
<10> Any one of <1> to <9>, wherein when the nonwoven fabric is pressurized at a pressure of 3.5 kPa, the height in the thickness direction of the first protrusion is higher than the height in the thickness direction of the ridge. The nonwoven fabric described in 1.
<11> The ratio (h1 / h5) between the height h1 in the thickness direction of the first protrusion and the height h5 of the ridge when the nonwoven fabric is pressurized at a pressure of 3.5 kPa is as follows. It is preferably 01 or more, more preferably 1.05 or more, further preferably 1.2 or more, and the upper limit is preferably 2.5 or less, and is 2.0 or less. The nonwoven fabric according to any one of <1> to <10>, more preferably 1.8 or less.
<12> The first projecting portion has a height h1 in the thickness direction, and its top portion has a steeper rising angle than a cone having a round shape like a hemisphere, and the top portion is a part of a hemisphere. The nonwoven fabric according to any one of <1> to <11>, which is a circular truncated cone.
<13> The nonwoven fabric according to any one of <1> to <12>, wherein the hydrophilicity of the top of the first protrusion is lower than that of the second protrusion and the wall.
<14> The nonwoven fabric according to any one of <1> to <13>, wherein the hydrophilicity of the top of the first protrusion is lower than the hydrophilicity of the ridge.
<15> The top of the first protrusion has a contact angle of ion exchange water at 22 ° C. of 80 ° or more, preferably 100 ° or more,
The preferred contact angle between the top of the second protrusion and the wall is such that the contact angle of the ion exchange water is 30 ° or more and less than 80 °, preferably 60 ° or more and 70 ° or less <1> to <14. > Any one of>.
Any one of <1> to <14>, wherein the <16> ridge has a contact angle of ion-exchanged water at 22 ° C. of 30 ° or more and less than 80 °, preferably 60 ° or more and 70 ° or less. The nonwoven fabric described in 1.
<17> On both the first surface side and the second surface side, the hydrophilicity of the top portion of the first protruding portion is lower than the portion excluding the top portion of the first protruding portion, or has hydrophobicity. The non-woven fabric according to any one of <1> to <16>, wherein the area of the first surface side at the top of the first protruding portion is less hydrophobic than the second surface side.
<18> The nonwoven fabric according to any one of <1> to <17>, wherein the two different directions are orthogonal to each other.
<19> The nonwoven fabric according to any one of <1> to <18>, wherein the wall portion forms an annular structure in the first projecting portion and the second projecting portion.
<20> The layer thickness TL1 of the top of the first protrusion, the layer thickness TL2 of the top of the second protrusion, and the layer thickness TL3 of the wall are TL1>TL3> TL2, and any one of <1> to <19> Or the nonwoven fabric according to 1.
<21> A topsheet for an absorbent article using the nonwoven fabric according to any one of <1> to <20>.
<22> A surface sheet for absorbent articles, wherein the nonwoven fabric according to any one of <1> to <20> is used with the first surface side facing the skin contact surface side.
<23> An absorbent article using the nonwoven fabric according to any one of <1> to <20> as a surface sheet.
<24> An absorbent article using the nonwoven fabric according to any one of <1> to <20> as a surface sheet with the first surface side facing the skin contact surface side.
<25> A concavo-convex shape is formed, a web containing thermoplastic fibers is conveyed to a heated support, and hot air is blown from the top of the web toward the support to shape the concavo-convex shape on the web. A method for producing a nonwoven fabric, comprising:
Heating the support to a temperature range from the glass transition point to the melting point of the fibers constituting the web; and
Temporarily fusing the fibers of the web to a state in which the uneven shape is maintained by blowing a first hot air; and
A step of blowing a second hot air having a temperature higher than that of the first hot air, and fixing the uneven shape by fusing the fibers of the web while maintaining the uneven shape. Production method.
<26> The temperature range for heating the support is preferably a temperature higher than the glass transition point of the fiber and 10 ° C. or lower than the melting point, more preferably a temperature 20 ° C. higher than the glass transition point of the fiber. As mentioned above, the manufacturing method of the nonwoven fabric as described in <25> below 20 degrees C lower than melting | fusing point.
<27> The method for producing a nonwoven fabric according to <25> or <26>, wherein the temperature of the support is within the temperature range when the first hot air is blown.
<28> Furthermore, the manufacturing method of the nonwoven fabric any one of <25> to <27> including the process of hydrophobizing the top part of the 1st protrusion part used as the said uneven | corrugated shaped convex part.
<29> A nonwoven fabric produced using the nonwoven fabric production method according to any one of <25> to <28>.
<30> A surface sheet for absorbent articles using the nonwoven fabric according to <29>.
<31> An absorbent article using the nonwoven fabric according to <29> as a surface sheet.

Hereinafter, the present invention will be described in more detail based on examples. The present invention is not construed as being limited by these examples.

[Example 1-9]
In Example 1, the core is made of polyethylene terephthalate (melting point 258 ° C., glass transition point 67 ° C.) and the sheath is made of polyethylene (melting point 135 ° C., glass transition point −20 ° C.). Then, a 2.4 dtex × 51 mm core-sheath type composite fiber having a hydrophilic surface was applied to a card machine so as to be a web 50 having a basis weight of 30 g / m ² , and the web 50 was supplied to a shaping apparatus. In the shaping apparatus, the web 50 was fixed on the support 110 having a large number of protrusions and air permeability. The support 110 is heated to 70 ° C. The MD pitch in the plan view of the protrusion 111 of the support 110 was 8 mm, the CD pitch was 5 mm, and the height of the protrusion 111 was 7.5 mm. Moreover, the hole diameter of the hole 112 in the support body 110 was 2.8 mm.
Next, the web 50 on the support 110 is blown with the first hot air W1 having a temperature of 130 ° C. and a wind speed of 50 m / s, and the web 50 is shaped along the protrusions 111 on the support 110. Next, it switched to the 2nd hot air W2 of temperature 145 degreeC and the wind speed of 5 m / s, and sprayed. And the shape of each core-sheath structure was fixed by fusing together. The support 110 is heated to 70 ° C. when the first hot air W1 is blown. Thus, the nonwoven fabric 10 was produced.
Example 2 was produced in the same manner as in Example 1 except that the heating temperature of the support 110 in Example 1 was changed to 90 ° C.
Example 3 was produced in the same manner as in Example 1 except that the heating temperature of the support 110 was 110 ° C. in Example 1 above.
In Example 4, the nonwoven fabric 10 of Example 1 was produced, and the hydrophobic treatment was further performed. As the hydrophobic agent, KM-903 (manufactured by Shin-Etsu Chemical Co., Ltd.) was used. The hydrophobic agent was dissolved in ethanol, adjusted to a 1.0% by weight solution, and applied to an acrylic plate at 4.3 mg / cm ² . Hydrophobic part 11D was produced by bringing the pressure of 2.0 kPa into contact with the first protrusion top part 11T over 10 seconds.
Example 5 was produced in the same manner as in Example 4 except that the heating temperature of the support 110 was changed to 90 ° C. in Example 4.
Example 6 was produced in the same manner as in Example 4 except that the heating temperature of the support 110 was changed to 110 ° C. in Example 4.
Example 7 was prepared in the same manner as in Example 5 except that KF-6011 (manufactured by Shin-Etsu Chemical Co., Ltd.) was used as the hydrophobic agent in Example 5.
Example 8 was prepared in the same manner as in Example 5 except that the web 50 was a two-layer product of core-sheath type composite fiber 2.4 dtex × 51 mm and 1.8 dtex × 51 mm.
Example 9 was produced in the same manner as in Example 8, except that the pressure applied to the plate in Example 8 was 1.5 kPa.

[Comparative Example 1-3]
Comparative Example 1 was produced in the same manner as in Example 1 except that the heating temperature of the support 110 was 40 ° C. in Example 1.
Comparative Example 2 was produced in the same manner as in Example 4 except that the heating temperature of the support 110 was 40 ° C. in Example 4.
In Comparative Example 3, the nonwoven fabric 10 of Comparative Example 2 was prepared, and further a KM-903 (manufactured by Shin-Etsu Chemical Co., Ltd.) 1.0 wt% ethanol solution was applied to the walls and ridges with a brush. This was prepared in the same manner as in Example 2 except that.

Next, a measurement method and an evaluation method will be described. The following measurement tests were performed using the above-mentioned nonwoven fabric test specimens.
<Support temperature measurement method>
Five seconds after stopping the shaping device, the temperature of the support at the position where the first hot air W1 was sprayed was measured using a contact thermometer. For the contact thermometer, ND500 manufactured by CHINO Co., Ltd. was used for the measuring instrument body, and C510-05K manufactured by CHINO Co., Ltd. was used for the measurement terminal. The temperature was measured three times, and the average value was defined as the support temperature.

<Measurement of fiber orientation (orientation angle, orientation strength)>
Using a scanning electron microscope JCM-5100 (trade name) manufactured by JEOL Ltd., the sample was allowed to stand so that the z-axis direction in FIG. An image taken from a direction perpendicular to the surface to be measured of the sample (adjusted to a magnification capable of measuring 10 or more fibers to be measured; 100 to 300 times) was printed. The printed fiber image was traced from the transparent PET sheet, and the fiber image was copied onto the transparent PET sheet. The image of the transparent PET sheet was taken into a personal computer, and the image was binarized using NexusNewQube [trade name] (stand-alone version) image processing software manufactured by Nexus Corporation. Then, the binarized image is subjected to Fourier transform using Fiber Orientation Analysis 8.13 Single software (trade name), which is a fiber orientation analysis program, to obtain a power spectrum, and from an elliptical distribution map, orientation is obtained. Corners and orientation strength were obtained.
The orientation angle indicates the angle at which the fibers are most oriented. The orientation strength indicates the strength at the orientation angle. In the measurement of the middle portion of the wall portion, it is shown that the fiber is oriented in the central direction of the top portion 11T as the orientation angle is closer to 90 °. And if an orientation angle is 60 degrees or more and 120 degrees or less, it will judge that the fiber has orientated in the center direction of the top part 11T.
Moreover, it represents that the direction of a fiber has gathered, so that the value of orientation strength is large. The case where the orientation strength is 1.05 or more is assumed to be oriented.
Measurement was performed at three locations, and the average was taken as the orientation angle and orientation strength of the sample.

The fiber orientation described above is a concept consisting of the orientation angle and orientation strength of the fiber.
The fiber orientation angle is a concept indicating in which direction a plurality of fibers having various directions are oriented as a whole. The shape of the fiber aggregate is digitized. The fiber orientation strength is a concept indicating the amount of fiber exhibiting an orientation angle. When the orientation strength is less than 1.05, there is almost no orientation. It can be said that it has an orientation at 1.05 or more. However, in this embodiment, the fiber orientation changes depending on the part. That is, it changes from a part with a certain orientation angle to a part with a different orientation angle. That is, the fiber changes from a state in which the orientation strength is strong in a certain direction to a portion that shows strong strength in a different orientation. In the meantime, it has various states such as a state in which the orientation strength is weak and a state in which the orientation strength is high by reorientation. Therefore, it is preferable that the orientation angle of the fiber is changed between a portion showing a strong orientation angle and a portion showing a strong orientation angle in another direction even if the orientation strength of the fiber is weak. And it is more preferable that orientation strength is high. An example of the orientation angle and orientation strength is shown in this embodiment. The orientation angle is preferably 50 ° or more and 130 ° or less, more preferably 60 ° or more and 120 with respect to the curved surface structure of the wall portion 13 of the first protrusion 11. ° or less. The orientation strength is preferably 1.05 or more, more preferably 1.10 or more. The wall portion 14 of the second protrusion 12 is the same as the wall portion 13.
When the nonwoven fabric 10 is used as the top sheet of the absorbent article, the nonwoven fabric 10 has sufficient compression resistance even under high pressure due to the fiber orientation of each wall portion 13. Thereby, the 1st protrusion part 11 of the nonwoven fabric 10 and the 2nd protrusion part 12 are prevented from collapsing. As a result, the nonwoven fabric 10 can secure a sufficient capture space and has an effect of reducing the contact area with the skin. Moreover, the nonwoven fabric 10 has high air permeability. Furthermore, the nonwoven fabric 10 sufficiently captures a large amount of liquid, solid content, high-viscosity liquid, etc., and sufficiently exhibits the effect of suppressing leakage.

<Measurement of thickness at 0.05 kPa pressure>
The cut surface of the nonwoven fabric 10 is enlarged to a size (10 times to 100 times) that can be measured by a digital microscope VHX-1000 manufactured by Keyence sufficiently to enter the visual field. Next, a weight is placed on the nonwoven fabric 10 so that a pressure of 0.05 kPa is applied. And the height h1 of the thickness direction of the 1st protrusion part 11 and the height h5 of the thickness direction of the ridge part 15 are measured. The measurement was performed 10 times, and the average value was defined as the height h1 of the first protrusion top portion 11T of the nonwoven fabric 10 and the height h5 of the ridge portion 15.
<Measurement of thickness at 3.5 kPa pressure>
The measuring method of the height h1 of the first projecting portion 11T and the height h5 of the ridge portion 15 under a pressure of 3.5 kPa seems to apply a pressure of 3.5 kPa to the weight of the thickness measuring method at a pressure of 0.05 kPa. The procedure was the same except that the adjustment was made.

<Measuring method of contact angle CA (°)>
The specific method for measuring the contact angle was as follows. A contact angle meter is used to measure the contact angle. For example, a contact angle meter MCA-J manufactured by Kyowa Interface Science Co., Ltd. is used. Specifically, after ion-exchanged water is dropped (about 20 picoliters) on the nonwoven fabric 10 to which the hydrophobic agent has been applied, the contact angle is measured immediately using the contact angle meter. The measurement is performed at five or more locations on the nonwoven fabric 10 and the average value thereof is taken as the contact angle. The measurement temperature is 22 ° C., and the relative humidity of the measurement atmosphere is 65%.
It is preferable that the 1st protrusion part top part 11T is hydrophobic, and it is preferable that the contact angle of ion-exchange water is 80 degrees or more. More preferably, it is 100 ° or more.
As a preferred contact angle of the portion excluding the first protrusion top 11T (second protrusion top 12T, wall 13 (14)), the contact angle of ion-exchanged water is 30 ° or more and less than 80 °. Preferably they are 60 degrees or more and 70 degrees or less. Therefore, the contact angle of the ridge portion 15 is preferably set to the above angle. Specifically, it is preferably 30 ° or more and less than 80 °, more preferably 60 ° or more and 70 ° or less. The lower the contact angle value measured here, the higher the hydrophilicity.

<Measurement method of rising angle>
The cut surface of the nonwoven fabric 10 is enlarged to a size (10 times to 100 times) that can be measured by a digital microscope VHX-1000 manufactured by Keyence sufficiently to enter the visual field. Then, the rising angle α of the first protrusion 11T is measured. As shown in FIG. 4B, the rising angle α is obtained as follows. A straight line Lv perpendicular to the straight line Lh connecting the tops 12T of the second protrusions 12 is drawn. The angle α formed by the straight line Lv and the tangent Lt of the nonwoven fabric (web 50) on the second surface side Z2 drawn from the second protrusion top 12T to the wall 14 is measured. The measurement was performed 10 times, and the average value of 10 times was defined as the rising angle α of the wall portion 13 (14) of the first protruding portion 11T of the nonwoven fabric 10.

<Measuring method of area of first surface side and area of second surface side of hydrophobic portion 11D>
The contact angle is measured every 0.2 mm on each of the first surface side and the second surface side of the hydrophobic portion 11D. The area in the range where the contact angle is 80 ° or more is measured by counting the number of squares of 0.2 mm square. The measurement results were defined as an area St1 on the first surface side and an area St2 on the second surface side of the hydrophobic portion 11D, respectively.

<Evaluation of compression recovery>
For compression recovery, a KES compression tester (KES FB-3 manufactured by Kato Tech Co., Ltd.) was used. The compression characteristics up to 5.0 kPa were evaluated in the normal mode, and the RC value was read. As measurement values, three points were measured and the average value was defined as compression recovery. This KES compression tester is a plate having a circular plane with an area of 2 cm ^{2 at} the compression site, the compression speed is 0.02 mm / s, the compression maximum pressure is 5.0 kPa, and the compression direction is reached when the compression maximum pressure is reached. Is reversed and the process proceeds to the recovery process. The RC value is a percentage of the recovered energy with respect to the energy during compression. The greater the RC value, the better the recovery from compression, the elasticity, and the better the cushioning. The RC value in the compression characteristic evaluation is the time integral value of the pressure from the time T ₀ when the initial pressure applied to the nonwoven fabric specimen is 0.05 kPa to the time T _m when the maximum pressure is 5.0 kPa, up to the maximum pressure of 5.0 kPa. Divided by the amount of work and expressed in%.

<Measurement method of liquid return amount>
The liquid return amount was measured using an infant diaper for evaluation. As an example of the absorbent article 100, the surface sheet was removed from an infant diaper, and a test specimen of the nonwoven fabric 10 (hereinafter referred to as a nonwoven test article) was used instead, and the periphery thereof was fixed. As the diaper for infants, Marys Sarasara Air-Through (registered trademark) M size, manufactured by Kao Corporation, used in 2012 was used.
A pressure of 3.5 kPa was applied uniformly on the non-woven fabric test piece, a cylinder having a cross-sectional area of 1000 mm ² placed at the approximate center of the test piece was applied, and artificial urine was injected therefrom. As the artificial urine, physiological saline was used, and a total of 160 g of artificial urine was infused 4 times by 40 g every 10 minutes.
After standing for 10 minutes from the completion of the injection, the above cylinder and pressure were removed. And filter paper No. made by Advantech Co., Ltd. A weight adjusted so as to apply a pressure of 3.5 kPa was placed on an absorbent sheet (mass = M1) in which 20 sheets of 5C (100 mm × 100 mm) were stacked, and these were placed on a nonwoven fabric specimen around the injection point.
After standing for 5 minutes, the weight was removed, and the mass (M2) of the filter paper was measured. And the liquid return amount was computed like following Formula.

Liquid return amount (g) = Mass of filter paper after pressurization (M2)-Mass of filter paper before pressurization (M1)

<Measurement method of liquid flow length>
For the liquid flow of the artificial urine, an infant diaper for evaluation was used. Artificial urine was supplied to it, and the distance from the supply position was measured.
The baby diaper for evaluation was obtained by removing the top sheet from the baby diaper and using a test body of the nonwoven fabric 10 instead, and fixing the periphery of the test body. As a diaper for infants, a product made in 2012 by Marys Sarasara Air-Through (registered trademark) M size manufactured by Kao Corporation was used.
In the measurement, a flat acrylic plate is tilted so that an inclined surface of 30 ° is obtained, and the evaluation diaper for infant is attached to the inclined surface and pressurized at 3.5 kPa. In that state, 40 g of physiological saline as artificial urine is injected into the infant diaper from the inlet arranged on the surface side of the infant diaper, and the amount of liquid flow from the inlet to the end of absorption of all the liquid from the inlet. The distance to the lower end of the liquid was measured in the longitudinal direction (longitudinal direction) of the absorbent article. In addition, when the injected liquid is absorbed obliquely from the longitudinal direction of the absorbent article, the shortest connecting the injection port and the lower end of the liquid absorbed obliquely along the longitudinal direction of the absorbent article The distance was the liquid flow length.

Table 1 shows the results of the physical properties (support temperature, orientation angle, orientation strength, thickness, contact angle, hydrophobic part area) and performance (compression recovery (RC value), liquid return amount, liquid flow) of the nonwoven fabric 10. Shown in

As shown in Table 1 above, in Examples 1 to 9, the thickness of the first protrusion 11 at a pressure of 3.5 kPa was 2.6 mm or more, and the liquid return amount was 1.3 g or less. This is because the heating temperature of the support 110 is in a suitable range, so that shaping can be performed along the shape of the support 110, and the rising angle is 20 ° or less. Thereby, the nonwoven fabric 10 became difficult to be crushed in the thickness direction. This shows that the RC value (%) is higher than that of the comparative example, and the cushioning property is improved.
In Examples 4 to 9, the liquid return amount was 0.8 g or less, and the liquid return amount decreased. This is because, in addition to the effects of the first to third embodiments, since the first protruding portion top portion 11T is hydrophobic on the first surface side Z1 that is the skin contact surface side, the remaining amount of the liquid that touches the skin This is because of the decrease. And it is because the liquid overflowing from the absorber is difficult to return to the first surface side Z1. The liquid flow length was 65 mm or less, and the liquid flow was small. This is because the heating temperature of the support 110 is in a suitable range, so that shaping along the shape of the support 110 can be performed, and the difference in height between the first protrusion 11 and the ridge 15 is increased. by. As a result, the liquid flow on the first surface side Z 1 of the nonwoven fabric 10 is caused to flow in an oblique direction with respect to the first direction X and the second direction Y.
On the other hand, in Comparative Example 1, since the heating temperature of the support 110 was as low as 40 ° C., shaping along the shape of the support 110 could not be performed. For this reason, the rising angle became 30 °, and the nonwoven fabric 10 was easily crushed in the thickness direction. And since there was no hydrophobic part in the 1st protrusion part top part 11T, the liquid return amount increased with 1.5g. Moreover, since there is no hydrophobic part in the 1st protrusion part top part 11T, since it does not depend on the difference of the height h1 of the 1st protrusion part 11 and the height h5 of the ridge part 15 under a heavy load, the amount of liquid flows is 58 mm. It became small.
Moreover, in Comparative Example 2 and Comparative Example 3, the liquid return amount was a little as 1.0 g and 0.9 g, and the liquid flow length was very long as 100 mm or more. This is because the heating temperature of the support 110 is as low as 40 ° C., and thus shaping along the shape of the support 110 cannot be performed. Moreover, it is because the difference of the height of the 1st protrusion part 11 and the ridge part 15 did not become large. As a result, the result that the effect similar to an Example was not fully exhibited was shown.
As described above, in Examples 1 to 9, both the liquid return amount and the surface liquid flow length were suppressed to low values. Therefore, it was found that Examples 1 to 9 were able to achieve both liquid return prevention and surface liquid flow prevention that could not be achieved in Comparative Examples 1 to 3.

While the invention has been described in conjunction with embodiments and examples thereof, it is not intended that the invention be limited in any detail to the description, unless otherwise specified, and that the spirit and nature of the invention as set forth in the appended claims be considered as such. I think it should be interpreted broadly without violating the scope.

This application claims priority based on Japanese Patent Application No. 2013-197183 filed in Japan on September 24, 2013 and Japanese Patent Application No. 2014-101815 filed on May 15, 2014 in Japan. Which are hereby incorporated by reference herein as part of their description.

DESCRIPTION OF SYMBOLS 1 Top surface sheet 2 Back surface sheet 3 Absorber 4 Main body 5 Side sheet 6 Fastening tape 7 Side leakage prevention gather 10 Nonwoven fabric 11 1st protrusion part 11D Hydrophobic part

11H Opening part

11K Internal space 11T 1st protrusion part top part 12 2nd protrusion part

12H Opening portion

12K Internal space 12T Second protrusion

top portion

13, 14 Wall portion 15 Ridge portion 16 Fiber 50 Web 100 Disposable diaper 110 Support body 111 Protrusion 112 Hole W1 First hot air W2 Second hot air

Claims

Production of a nonwoven fabric having a concavo-convex shape, transporting a web containing thermoplastic fibers to a heated support, and blowing hot air from above the web toward the support to shape the concavo-convex shape on the web A method,
Heating the support to a temperature range from the glass transition point to the melting point of the fibers constituting the web; and
Temporarily fusing the fibers of the web to a state in which the uneven shape is maintained by blowing a first hot air; and
A method for producing a nonwoven fabric, comprising: blowing a second hot air having a temperature higher than that of the first hot air, and fixing the uneven shape by fusing the fibers of the web while maintaining the uneven shape. .
The method for producing a nonwoven fabric according to claim 1, wherein the temperature range for heating the support is not less than a temperature higher than the glass transition point of the fiber and not more than 10 ° C lower than the melting point.
The method for producing a nonwoven fabric according to claim 1 or 2, wherein the temperature range for heating the support is at least 20 ° C higher than the glass transition point of the fiber and not higher than 20 ° C lower than the melting point.
The method for producing a nonwoven fabric according to any one of claims 1 to 3, wherein the temperature of the support is within the temperature range when the first hot air is blown.
The manufacturing method of the nonwoven fabric of any one of Claim 1 to 4 including the process of hydrophobizing the top part of the 1st protrusion part used as the said uneven | corrugated shaped convex part.
The nonwoven fabric manufactured using the manufacturing method of the nonwoven fabric of any one of Claim 1 to 5.
A surface sheet for absorbent articles using the nonwoven fabric according to claim 6.
An absorbent article using the nonwoven fabric according to claim 6 as a surface sheet.
A first projecting portion projecting to the first surface side of the sheet body in a plan view and having an internal space;
A second projecting portion projecting on the second surface side opposite to the first projecting portion and having an internal space;
A plurality of the first protrusions and the second protrusions are alternately and continuously arranged through wall portions in different directions intersecting in plan view of the nonwoven fabric,
The adjacent first protrusions and the adjacent second protrusions are nonwoven fabrics that are continuously connected in an oblique direction in plan view with respect to each of the different directions via the ridges, respectively.
When pressurizing the nonwoven fabric at a pressure of 0.05 kPa,
The height in the thickness direction of the first protrusion is higher than the height in the thickness direction of the ridge,
The nonwoven fabric whose rise angle of the wall part of the said 1st protrusion part is 0 degree or more and 20 degrees or less.
The nonwoven fabric according to claim 9, wherein a rising angle of the wall portion of the first protrusion is not less than 0 ° and not more than 15 °.
The nonwoven fabric according to claim 9, wherein the rising angle of the wall portion of the first protrusion is not less than 0 ° and not more than 12 °.
The fiber which comprises the wall part of the said 1st protrusion part has fiber orientation in the direction which ties the top part of the said 1st protrusion part, and the edge part of the opening part of the internal space of the said 1st protrusion part. Item 12. The nonwoven fabric according to any one of Items 9 to 11.
The non-woven fabric according to any one of claims 9 to 12, wherein the fibers constituting the wall portion of the first protruding portion have fiber orientation in a direction in which the wall portion stands.
The nonwoven fabric according to any one of claims 9 to 13, wherein the fibers constituting the wall of the first protrusion have a radial fiber orientation toward the top of the first protrusion.
The fiber which comprises the wall part of a said 2nd protrusion part has a fiber orientation in the direction which connects the edge part of the opening part of the said 2nd protrusion part and its internal space in any one of Claim 9 to 14 The nonwoven fabric described.
The nonwoven fabric according to any one of claims 9 to 15, wherein an orientation angle of each wall portion of the first projecting portion and the second projecting portion is 50 ° to 130 °, and an orientation strength is 1.05 or more. .
The nonwoven fabric according to any one of claims 9 to 15, wherein an orientation angle of each wall portion of the first projecting portion and the second projecting portion is 60 ° to 120 °, and an orientation strength is 1.10 or more. .
The nonwoven fabric according to any one of claims 9 to 15, wherein an orientation angle of each wall portion of the first projecting portion and the second projecting portion is 85 ° to 95 ° and an orientation strength is 1.30 or more. .
The height of the thickness direction of the said 1st protrusion part when the said nonwoven fabric is pressurized by the pressure of 3.5 kPa is higher than the height of the thickness direction of the said ridge part. Non-woven fabric.
The ratio h1 / h5 of the height h1 in the thickness direction of the first protrusion and the height h5 of the ridge when the nonwoven fabric is pressurized at a pressure of 3.5 kPa is 1.01 or more and 2.5. The nonwoven fabric according to any one of claims 9 to 19, which is:
A ratio h1 / h5 of the height h1 in the thickness direction of the first protrusion and the height h5 of the ridge when the nonwoven fabric is pressurized at a pressure of 3.5 kPa is 1.05 or more. The nonwoven fabric according to any one of claims 9 to 19, which is 0.0 or less.
A ratio h1 / h5 between the height h1 in the thickness direction of the first protrusion and the height h5 of the ridge when the nonwoven fabric is pressurized at a pressure of 3.5 kPa is 1.2 or more. 20. The nonwoven fabric according to any one of claims 9 to 19, which is 8 or less.
The first protrusion is a truncated cone having a height h1 in the thickness direction with a steeper rising angle of the wall than a cone having a hemispherical round at the top, and a portion having a rounded hemisphere at the top. The nonwoven fabric according to any one of claims 9 to 22.
The nonwoven fabric according to any one of claims 9 to 23, wherein the hydrophilicity of the top of the first protrusion is lower than the top of the second protrusion and the wall.
The nonwoven fabric according to any one of claims 9 to 24, wherein the hydrophilicity of the top of the first protrusion is lower than the hydrophilicity of the ridge.
The contact angle of ion exchange water at 22 ° C. is 80 ° or more at the top of the first protrusion, and the contact angle of ion exchange water at 22 ° C. is 30 ° at the top of the second protrusion and the wall. The nonwoven fabric according to any one of claims 9 to 25, wherein the nonwoven fabric is less than 80 °.
The contact angle of ion exchange water at 22 ° C. is 100 ° or more at the top of the first protrusion, and the contact angle of ion exchange water at 22 ° C. is 60 ° at the top of the second protrusion and the wall. The nonwoven fabric according to any one of claims 9 to 25, wherein the nonwoven fabric is 70 ° or more and 70 ° or less.
The nonwoven fabric according to any one of claims 9 to 27, wherein the ridge portion has a contact angle of ion exchange water at 22 ° C of 30 ° or more and less than 80 °.
The nonwoven fabric according to any one of claims 9 to 27, wherein a contact angle of the ion exchange water at 22 ° C is 60 ° or more and 70 ° or less.
On both the first surface side and the second surface side, the top of the first protrusion is lower in hydrophilicity or hydrophobic than the portion excluding the top of the first protrusion, 30. The nonwoven fabric according to any one of claims 9 to 29, wherein an area where the first surface side is hydrophobized is smaller than the second surface side at the top portion of the first protrusion.
The nonwoven fabric according to any one of claims 9 to 30, wherein the two different directions are orthogonal to each other.
The non-woven fabric according to any one of claims 9 to 31, wherein the wall portion forms an annular structure in the first projecting portion and the second projecting portion.
The layer thickness TL1 of the top of the first protrusion, the layer thickness TL2 of the top of the second protrusion, and the layer thickness TL3 of the wall are TL1> TL3> TL2. Non-woven fabric.
A top sheet for absorbent articles, wherein the nonwoven fabric according to any one of claims 9 to 33 is used with the first surface side facing the skin contact surface side.
An absorbent article using the nonwoven fabric according to any one of claims 9 to 33 as a surface sheet with the first surface side facing the skin contact surface side.