JP5985258B2 - Non-woven - Google Patents

Description

  The present invention relates to a nonwoven fabric.

Absorbent articles such as sanitary napkins, panty liners, disposable diapers, etc., depending on its function, those with a protruding part on one side of the sheet material, those with a protruding part, and many Products with small holes have been developed.
Patent Document 1 discloses a non-woven fabric in which convex portions and open concave portions are dispersed and disposed throughout, and the fiber aggregate density of the concave portions is lower than the fiber aggregate density of the convex portions. It is disclosed. Thereby, it is said that the leakage of the high-viscosity body fluid is surely suppressed or prevented, and also has other required characteristics, and has excellent performance as a surface material of the absorbent article. As shown in FIG. 1, the non-woven fabric of Patent Document 1 has a concave portion substantially perforated, and the convex portion and the concave portion are not continuous.

  Patent Document 2 discloses an absorbent article in which a first fiber layer disposed on the skin side and a second fiber layer including heat-shrinkable fibers disposed on the absorber side are laminated and partially joined. A surface sheet is disclosed. The first fiber layer has a convex portion on the skin side other than a joint portion formed by embossing or the like, and the second fiber layer has a heat-shrinkable portion thermally contracted and a high-density portion in which heat shrinkage is suppressed. With respect to the heat shrinkage of the second fiber layer, the first fiber layer has a raised convex shape (dome shape) so as to increase the inter-fiber distance. Thereby, a density difference arises between a 1st fiber layer and a 2nd fiber layer, and a liquid can be rapidly transferred from the convex-shaped part of a 1st fiber layer to a 2nd fiber layer. In the surface sheet of Patent Document 2, only the skin surface side is convex.

  Patent Document 3 discloses a bulky nonwoven fabric for wipers that includes heat-shrinkable fibers and non-shrinkable fibers, and has a large number of wrinkles formed on both sides by heat shrinkage of the heat-shrinkable fibers. The bulky nonwoven fabric is said to have excellent wiping performance and excellent wear resistance. However, the collar portion is formed by the surface shrinkage of the fiber web, that is, the shrinkage of the heat-shrinkable fibers in the plane direction. Therefore, the cushioning property against pressure in the thickness direction is inferior. Further, a dense structure of fibers is formed in the heel part, and the liquid permeability is poor.

Japanese Patent Laid-Open No. 03-137258 Japanese Patent Laid-Open No. 2004-466 JP 09-67748 A

  An object of the present invention is to provide a nonwoven fabric that has good cushioning properties and excellent liquid permeability as well as liquid trapping properties.

  The present invention has a first projecting portion projecting on the first surface side of the sheet-like nonwoven fabric in plan view and having an internal space, and projecting on the second surface side opposite to the first surface side and having an internal space. A second protrusion, and the first and second protrusions are alternately and continuously arranged in different directions intersecting in plan view of the nonwoven fabric, and the first protrusion and the second Provided is a nonwoven fabric in which the protruding portion is integrated with the wall portion and contains a coiled fiber as a constituent fiber.

  The nonwoven fabric of the present invention has good cushioning properties and excellent liquid permeability as well as liquid trapping properties.

It is the fragmentary sectional perspective view which showed typically the principal part which showed preferable one Embodiment of the nonwoven fabric of this invention. It is the longitudinal cross-sectional view of the 1st protrusion part of the nonwoven fabric of this invention, a 2nd protrusion part, and a wall part, (a-1) and (a-2) shown in three circles are fiber orientation of a wall part (B) is explanatory drawing which showed typically the orientation of the fiber of the top part of a 1st protrusion part. It is a cross-sectional view of the center part of the sheet thickness in the wall part of the nonwoven fabric of this invention. It is a longitudinal cross-sectional view of the wall part and 2nd protrusion part of the nonwoven fabric of this invention. It is the plane arrangement | positioning figure which showed the example of arrangement | positioning of the 1st, 2nd protrusion part of the nonwoven fabric of this invention. It is explanatory drawing which showed one preferable embodiment of the manufacturing method of the nonwoven fabric of this invention, (1) shows the mode of blowing of a 1st hot air, (2) shows the fiber web by blowing a 1st hot air. The state is shown, and (3) shows the state of wiping the second hot air. 2 is a drawing-substituting photograph in which a wall portion of a nonwoven fabric test body produced in Example 1 is imaged. 4 is a drawing-substituting photograph in which the top of the first protrusion of the nonwoven fabric test body produced in Example 1 is imaged.

A preferred embodiment of the nonwoven fabric according to the present invention will be described below with reference to FIGS.
The nonwoven fabric 10 of the present invention is preferably applied to a surface sheet of an absorbent article such as a sanitary napkin or a disposable diaper. The first surface side Z1 is used with the skin surface side of the wearer, and the second surface side Z2 is used. Is preferably disposed on the absorbent body (not shown) side inside the absorbent article. Hereinafter, although it demonstrates considering the embodiment which uses the 1st surface side Z1 of the nonwoven fabric 10 shown in drawing toward a wearer's skin surface, this invention is limited to this and is not interpreted.

  As shown in FIG. 1, the nonwoven fabric 10 of the present invention has a first protrusion 11 protruding from the first surface side Z1 on the side of the sheet-like nonwoven fabric in plan view and having an internal space 11K, and the first surface side Z1. It has the 2nd protrusion part 12 which protrudes in the 2nd surface side Z2 of an other side, and has the internal space 12K. These 1st, 2nd protrusion parts 11 and 12 are distribute | arranged alternately by each of the different direction which crosses planar view over the whole surface of the nonwoven fabric 10, for example. The different direction is, as a specific example, an X direction which is one direction of the different directions and a Y direction which is one direction of the different directions unlike the X direction. Here, the convex portion viewed from the first surface side Z <b> 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 <b> 2 is the second projecting portion 12, and the concave portion is the first projecting portion 11. And the internal space 12K which the 2nd protrusion part 12 has is the space formed in the said recessed part which looked at the 2nd protrusion part 12 from the 1st surface side Z1, and is open | released toward the 1st surface side Z1. . The internal space 11K of the first protrusion 11 is a space formed in the recess when the first protrusion 11 is viewed from the second surface side Z2, and is open toward the second surface side Z2. A part of the first protrusion 11 and the second protrusion 12 is shared.

  In this embodiment, the 1st, 2nd protrusion parts 11 and 12 are made into the truncated cone shape or hemisphere which rounded the top parts 11T and 12T. More specifically, the protruding shape of the first protruding portion 11 is somewhat hemispherical, while the protruding shape of the second protruding portion 12 is a cone or truncated cone shape with a round top. In addition, in this embodiment, the 1st, 2nd protrusion parts 11 and 12 are not limited to the said shape, What kind of protrusion form may be sufficient, for example, various cone shape (In this specification, cone shape is It is practical to include a cone, a truncated cone, a pyramid, a truncated pyramid, an oblique cone, etc.). In this embodiment, the 1st, 2nd protrusion parts 11 and 12 hold | maintain the frustoconical shape or hemispherical internal space 11K and 12K with the roundness in the top part similar to the external shape.

  In the nonwoven fabric 10, the wall part 15 is interposed between the 1st protrusion part 11 and the 2nd protrusion part 12, Thereby, both protrusion parts make the structure continuous integrally. That is, the unevenness in the sheet thickness direction is alternately continued in the plane direction, and the entire nonwoven fabric 10 does not have a bent portion and forms a continuous curved surface. Thus, the nonwoven fabric 10 has a continuous structure 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 mm or more. Thus, the wall portion 15 is continuous with the first protrusion portion 11 and the second protrusion portion 12, and does not have a clear boundary between the respective portions, and the first protrusion portion 11 and the second protrusion portion 12 It can be said that it is an overlapping part.

As the section of the wall portion 15, for example, as shown in FIG. 2, the central portion (P ₂ ) of the nonwoven fabric 10 divided into three equal parts (P ₁ , P ₂ , P ₃ ) in the sheet thickness (T). Can be defined. In this case, the section (P ₁ ) on the first surface side Z ₁ becomes the first protrusion 11, and the section (P ₃ ) on the second surface side Z 2 becomes the second protrusion 12. Accordingly, these thicknesses are naturally determined by the sheet thickness (T) (P ₁ = P ₂ = P ₃ ). However, when the kurtosis or curvature of the tops of the first protrusions 11 and the second protrusions 12 are different, the wall part 15 is a relatively narrow part that is linear in the cross section, and is curved and rounded from there. optionally a go area as the first protrusion 11 and second protrusion 12, respectively _(P 1, P reference _'2, P' _3). If due to the latter definition, in the nonwoven fabric 10 of the present embodiment, the second projecting portion 2 of the thickness (P _'3) is greater than the thickness (P ₁₎ of the first projecting portion 11, a biased in the thickness direction in the entire It is in the form. In other words, in the present embodiment, the radius of curvature of the top portion 11T of the first protruding portion top portion 11 is made larger than the radius of curvature of the top portion 12T of the second protruding portion top portion 12.

  Alternatively, the wall portion 15 may be defined as a side wall that separates the internal space 11K and the internal space 12K. Specifically, the wall portion 15 is a nonwoven fabric portion sandwiched between the opening 12H of the internal space 12K and the opening 11H of the internal space 11K. The opening 12H is a portion formed by connecting the positions of the first ridges 16, 16,... That connect the first protrusions 11 that surround the periphery of the internal space 12K to the second protrusion 12 side. . The opening 11H is a portion formed by connecting the positions of the second ridges 17, 17,... That connect the second protrusions surrounding the inner space 11K to the first protrusion 11 side.

  Since the wall 15 separates the internal space 12K and the internal space 11K as described above, it forms an annular structure that forms the outer edge of both internal spaces. The “annular” herein is not particularly limited as long as it has a series of endless shapes in plan view, and may be any shape such as a circle, an ellipse, a rectangle, or a polygon in plan view. In order to maintain the continuous state of the sheet suitably, a circle or an ellipse is preferable. Furthermore, if the "annular" is considered as a three-dimensional shape, a cylindrical shape, an oblique cylindrical shape, an elliptical columnar shape, a truncated cone shape, a truncated oblique cone shape, a truncated elliptical cone shape, a truncated rectangular pyramid shape, a truncated oblique pyramid shape Arbitrary ring structures, such as a shape, are mentioned, In order to implement | achieve a continuous sheet | seat state, cylindrical shape, elliptic cylinder shape, truncated cone shape, and truncated elliptical cone shape are preferable.

As a fiber material constituting the nonwoven fabric 10, the coiled fiber 1 is contained. The coiled fiber 1 has a property that its helical structure exhibits a spring-like movement and attempts to return to its original state when it is compressed. From this property, the cushioning property and elasticity in the nonwoven fabric 10 can be made favorable. In particular, the coiled fiber 1 is preferably oriented in the sheet thickness direction, that is, in the standing direction of the wall portion 15 in the wall portion 15 (see FIG. 2 in the circles (a-1) and (a-2)). ). The standing direction is the direction connecting the first protrusion 11 and the second protrusion 12, the direction connecting the opening 11H and the second protrusion 12, or connecting the opening 12H and the first protrusion 11. It is also a direction.
In the wall 15, the longitudinal direction of the coiled fiber 1, that is, the crimping expansion / contraction direction is in the sheet thickness direction, so that the coil-like fiber 1 has a spring-like characteristic with respect to the pressure in the thickness direction against the nonwoven fabric. Becomes more effective. Thereby, even if various pressures are applied to the nonwoven fabric 10, the compression recovery of the shape is excellent, and the uneven structure of the nonwoven fabric 10 that connects the first protruding portion and the second protruding portion via the wall portion 15. Is easy to maintain and is preferable.

As the coiled fiber 1, for example, a fiber that is spirally formed by a method other than heat, a fiber that originally has a spiral portion, or the like can be used. These are called actual crimped fibers to distinguish from latent crimped fibers described later.
The actual crimped fiber is composed of, for example, an eccentric core-sheath type composite fiber or a side-by-side type composite fiber containing two types of thermoplastic polymer materials having different melting points as components. For example, a combination of polyethylene (PE) and polyester (PET), polyethylene (PE) and polypropylene (PP) is preferable. Further, as components other than those described above, thermoplastic resins such as low melting point polypropylene, polytrimethylene terephthalate (PTT), and polyamide may be used in combination.

In addition, as the coiled fiber 1, for example, a latent crimpable fiber formed by spiral crimping can be employed. The latent crimpable fiber does not develop a coiled crimp before being heated, but has a property of shrinking by heating at a predetermined crimping start temperature or higher, thereby producing a coiled crimp. Fiber.
The latent crimpable fiber is composed of, for example, an eccentric core-sheath type composite fiber or a side-by-side type composite fiber containing two types of thermoplastic polymer materials having different shrinkage rates, and different specific shrinkage rates. As an example of two types of thermoplastic polymer materials, for example, a combination of an ethylene-propylene random copolymer (EP) and polypropylene (PP), or a polyethylene (PE) and polypropylene (PP) is preferably exemplified. In addition, combinations of α-olefin and a propylene copolymer, an ethylene-propylene-butene-13 terpolymer, and the like are also exemplified, and not only the above-mentioned resins but also other resins can be used.

  From the viewpoint of the cushioning property, when the actual crimped fiber is used as the coiled fiber, the content of the coiled fiber 1 in the entire nonwoven fabric 10 is preferably 10% or more, more preferably 30% or more. More preferably, it is more preferably 50% or more. Further, the content is preferably 100% or less, and more preferably 80% or less. This content rate is the ratio of the weight of the coiled fiber 1 to the whole constituent fiber of the nonwoven fabric 10.

  On the other hand, when the latent crimped fiber is used as the coiled fiber, it is preferable that it is larger from the viewpoint of cushioning properties, but considering the strike through viewpoint, the content of the coiled fiber 1 in the entire nonwoven fabric 10 is as follows. It is preferably 10% or more, and more preferably 20% or more. The content is preferably 30 or less.

From the same viewpoint, the coiled fiber 1 in the wall 15 preferably has an orientation angle of 40 ° or more and 140 ° or less with respect to the horizontal plane of the sheet of the nonwoven fabric 10 (the XY plane in FIG. 1). More preferably, it is 50 ° or more and 130 ° or less. A favorable cushioning property can be acquired by setting it as the said minimum or more.
In the present invention, unless otherwise specified, the direction along the sheet thickness direction is an orientation angle of 90 °, and in the state shown in FIG. 1, the Z-axis (Z1-Z2) direction corresponds to this. In addition, the orientation angle of the coiled fiber 1 can be measured by the <Measurement Method of Fiber Orientation (Orientation Angle, Orientation Strength)> described below, and the angle with respect to the horizontal plane (XY plane) Although it may be measured from either direction as long as the Z-axis is measured up and down, it is practical to set the angle measured with the surface along the CD at the time of manufacturing the nonwoven fabric as the front. This also applies to the orientation angle and the ratio of the two-dimensional crimped fiber 2 in the first protrusion 11 described later. The MD is also referred to as a machine direction, which is a fiber web feeding direction when manufacturing a nonwoven fabric, and is an abbreviation for “Machine Direction”. The CD is a direction orthogonal to the MD and is an abbreviation of “Cross Direction”.

  Further, in the wall portion 15, it is preferable that the entire constituent fiber including the coiled fiber 1 has a fiber orientation toward the standing direction of the wall portion 15 at any location of the wall portion 15. Thereby, more excellent cushioning properties can be obtained. Specifically, the direction connecting the first protruding portion top 11T and the edge of the opening 11H, the direction connecting the second protruding portion top 12T and the edge of the opening 12H, the first protruding portion 11 and the second protrusion. It has fiber orientation in the direction connecting the part 12. Therefore, it has the radial fiber orientation which goes to the 1st protrusion part top part 11T thru | or the 2nd protrusion part top part 12T.

  The fiber orientation is a concept consisting of an orientation angle and orientation strength of fibers. The fiber orientation angle is a concept that indicates in which direction a plurality of fibers having various directions are oriented as a whole, and the shape of the fiber aggregate is quantified. The orientation strength of the fiber is a concept indicating the amount of fibers exhibiting an orientation angle. The orientation strength is less than 1.05 and is hardly oriented, and it can be said that the orientation strength is 1.05 or more. However, in this embodiment, the fiber orientation changes depending on the part. That is, the orientation strength is changed during the transition from a part having a certain orientation angle to a part having a different orientation angle (while the fiber is changing from a state in which the orientation strength is strong in one direction to a part having a strong strength in a different orientation). It has various states such as a weak state and a high state due to reorientation. Therefore, it is preferable that the orientation angle of the fiber is changed between the part showing a strong orientation angle and the part showing a strong orientation angle in another direction even if the orientation strength of the fiber is weak, and the orientation strength is high. Is more preferable.

For example, in the cross section of the internal space 12K shown in FIG. 3, the wall portion that the virtual line Lwx along the first direction X in the cross section passing through the center point Mw of the cross section of the wall portion 15 crosses. The fiber orientation is as follows between 15wX and the wall portion 15wY crossed by the virtual line Lwy along the second direction Y in the transverse section passing through the center point Mw. The orientation angle of the wall portion 15wX is 40 ° to 140 °, preferably 55 ° to 125, when the Mw direction (sheet thickness direction, Z1-Z2 direction) indicated by a two-dot chain line in FIG. °, more preferably 60 ° to 120 °. The orientation angle of the wall portion 15wY is 40 ° to 140 °, preferably 55 ° to 125 ° when the Mw direction (sheet thickness direction, Z1-Z2 direction) shown in FIG. 4 is 90 °. More preferably, the angle is 60 ° to 120 °. The orientation strength of the wall portion 15wX is 1.05 or more, more preferably 1.1 or more, and further preferably 1.20 or more. The orientation strength of the wall portion 15wY is 1.05 or more, more preferably 1.1 or more, and further preferably 1.20 or more.
Thus, both the wall portion 15wX and the wall portion 15wY are not easily crushed by being oriented toward the center of the protruding portion, and can maintain high cushioning properties and absorption performance. Further, when the nonwoven fabric 10 is used as a surface sheet of an absorbent article, each wall portion 15 has a structure that supports the first projecting portion 11 and the second projecting portion 12 by supporting the fiber orientation. Combined with the compression recovery property of the coiled fiber 1, the nonwoven fabric has sufficient compression resistance and prevents plastic deformation of the nonwoven fabric. As a result, a sufficient capture space can be ensured, and the effect of reducing the skin contact area, high air permeability, a large amount of liquid, solid content, highly viscous liquid, etc. can be sufficiently captured and the effect of suppressing leakage can be sufficiently exhibited.

The nonwoven fabric 10 may contain the two-dimensional crimped fiber 2 together with the aforementioned coiled fiber 1 (see FIG. 2). The two-dimensional crimped fiber 2 is one in which crimping of the fiber occurs in a planar manner, and includes, for example, a fiber that is curved left and right with respect to the longitudinal direction of the fiber.
As the two-dimensional crimped fiber 2, various fiber materials that can be used for the nonwoven fabric can be used without any particular limitation. Specific examples include the following fibers. Polyolefin fibers such as polyethylene (PE) fibers and polypropylene (PP) fibers; fibers made of a single thermoplastic resin such as polyethylene terephthalate (PET), polytrimethylene terephthalate (PTT), polyamide; core-sheath type, side-by-side type Preferred examples include composite fibers having a structure such as a core / sheath fiber in which the sheath component is polyethylene or low melting point polypropylene, and typical examples of the core / sheath fiber include PET (core) and PE (sheath). , PP (core) and PE (sheath), PP (core) and low melting point PP (sheath) and other core-sheathed fibers. 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, and the composite composition of the polypropylene composite fiber is preferably polyethylene terephthalate and low-melting polypropylene, and more specifically, PET (core). And PE (sheath), PET (core), and low melting point PP (sheath). These fibers may be used alone to form a nonwoven fabric, but may be used in combination of two or more.

  The two-dimensional crimped fiber 2 does not have a three-dimensional bent portion that may cause a liquid pool, and easily moves the liquid along the orientation of the fiber. Such a two-dimensional crimped fiber 2 is preferably oriented in the sheet thickness direction of the nonwoven fabric 10 in the vicinity of the first projecting portion 11 of the nonwoven fabric 10, particularly the top portion 11 </ b> T (see FIG. 2 (b) in the circle). ). Thereby, the liquid easily moves in the sheet thickness direction along the two-dimensional crimped fiber 2, and the liquid flow resistance in the first protruding portion 11 is reduced. As a result, for example, when the nonwoven fabric 10 is used as the top sheet of the absorbent article and the first protruding portion 11 is disposed toward the skin contact surface side, the first protruding portion 11 that is closest to the skin in the nonwoven fabric 10. The excretory fluid can be quickly permeated into the internal space 11T on the second surface side Z2 and delivered to the absorber.

In addition, in the first projecting portion 11, there is one in which a part of the two-dimensional crimped fiber 2 is taken into the coiled fiber 1 to become a fiber assembly 3, and the two-dimensional crimped fiber 2 in the fiber assembly 3. Is preferably upright with respect to the longitudinal direction of the coiled fiber 1 (see FIG. 2 (b)). And when the two-dimensional crimped fiber 2 in the fiber assembly 3 is oriented in the sheet thickness direction of the nonwoven fabric 10 while being held by the coiled fiber 1, the good permeability of the liquid can be maintained. Is preferable. At this time, the longitudinal direction of the coiled fiber 1 is arranged to intersect the sheet thickness direction, but even in that case, the winding direction of each spiral portion of the coiled fiber 1 is easily along the sheet thickness direction, Can contribute to permeability.
Further, regarding the liquid permeability, the coiled fiber 1 becomes a dense portion of the fiber in the spiral portion and has a capillary force. Therefore, in the fiber assembly 3, the liquid can be further drawn into the inside by the capillary force of the coiled fiber 1 while the liquid is drawn in by the standing two-dimensional crimped fiber 2 without liquid passing resistance. In addition, it is preferable that the network structure is formed by the two-dimensional crimped fibers 2 while the coiled fibers 1 are appropriately separated from each other, which further improves liquid permeability.

  Further, regarding the fiber assembly 3, the arrangement of the two-dimensional crimped fiber 2 is fixed by the coiled fiber 1 taking in the two-dimensional crimped fiber 2 regardless of the orientation of the two-dimensional crimped fiber 2. In addition, the fiber orientation can be stabilized, and as a result, the shape of the first protrusion 11 can be stabilized. Thereby, the settling of the first protrusion 11 which is easily affected by various pressures and liquid impregnation applied to the nonwoven fabric 10 is prevented, which is preferable for improving compression recovery. And if the fiber assembly 3 is dispersed to some extent, the entanglement between the two-dimensional crimped fibers 2 can be suppressed, and a suitable inter-fiber distance and fiber orientation can be maintained, so that the viewpoint of liquid permeability Is also preferable.

  From the viewpoint of liquid permeability of the first protrusion 11 described above, the two-dimensional crimped fiber 2 in the fiber assembly 3 in the first protrusion 11 is a horizontal plane of the sheet of the nonwoven fabric 10 (XY plane in FIG. 1). The orientation angle is preferably 40 ° or more and 140 ° or less, and more preferably 50 ° or more and 130 ° or less. By setting it to the lower limit or more, good liquid permeability can be obtained.

The fiber orientation (orientation angle and orientation strength) of the coiled fiber 1 in the wall 15 and the two-dimensional crimped fiber 2 in the first protrusion 11 can be measured by the following methods.
<Measurement method of fiber orientation (orientation angle, orientation strength)>
First, using a KEYENCE digital microscope VHX-1000, the sample is enlarged so that the part to be measured can sufficiently enter the field of view (10 to 100 times) and the z-axis direction in FIG. The image taken from a direction perpendicular to the surface to be measured of the sample is printed, and the fiber is traced on the transparent PET sheet. The said image is taken in in a personal computer and the said image is binarized using the NexusNewQube [brand name] (stand-alone version) image processing software made from Nexus Corporation. Next, the binarized image was 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, an orientation angle was obtained. And get the orientation strength.
The orientation angle indicates the angle at which the fibers are most oriented, and the orientation strength indicates the strength at the orientation angle. As the orientation angle is closer to 90 °, the coiled fibers in the wall 15 are oriented in the sheet thickness direction (the direction from the top 11T of the first protrusion 11 to the top 12T of the second protrusion 12). It shows that the two-dimensional crimped fibers in the first protrusion 11 are oriented in the sheet thickness direction. If the orientation angle is 40 ° to 140 °, it is determined that the orientation of the coiled fiber in the wall portion 15 and the two-dimensional crimped fiber in the first protruding portion 11 is shown. 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. The measurement is performed at three places, and the average is taken as the orientation angle and orientation strength of the sample.

The number of crimps (the number of peaks per 25.4 mm) of the coiled fiber 1 is preferably 5 to 30, and more preferably 10 to 20, from the viewpoint of the above cushioning properties and spinnability. In addition, the fineness of the coiled fiber 1 is preferably 1 to 10 dtex, and more preferably 4 dtex or less, from the viewpoint of texture.
There is no restriction | limiting in particular in the cross-sectional shape of the coil-shaped fiber 1, For example, circular, an ellipse shape, a dumbbell shape, etc. are mentioned.

Next, the dimension specification in the nonwoven fabric 10 of this embodiment is demonstrated below.
Regarding the thickness of the sheet, the total thickness when viewed from the side of the nonwoven fabric 10 is the sheet thickness TS, and the local thickness of the sheet curved in the unevenness is the layer thickness TL (see FIG. 1). The sheet thickness TS may be adjusted as appropriate depending on the application, but when used as a surface sheet for diapers, sanitary products, etc., 1 mm to 7 mm is preferable, and 1.5 mm to 5 mm 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 in each part in the sheet, and may be appropriately adjusted depending on the application. When used as a top sheet for diapers, sanitary products, etc., the layer thickness TL1 of the first protrusion top 11T is preferably 0.1 mm to 3 mm, more preferably 0.4 mm to 2 mm. 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 15. The relationship between the layer thicknesses TL1, TL2, and TL3 is preferably TL1>TL3> TL2. Thereby, in the 1st protrusion part 11, especially on the skin surface side, fiber density is low and can implement | achieve favorable skin contact. On the other hand, the second protrusion 12 has a high fiber density, is not easily crushed, and can be made of a nonwoven fabric excellent in cushioning properties and liquid absorption speed without being deformed.
What is necessary is just to adjust suitably the space | interval of the said 1st protrusion part 11 and the 2nd protrusion part 12 according to a use, and when using as surface sheets, such as a diaper and sanitary goods, 1 mm-15 mm are preferable, and 3 mm-10 mm are more preferable. The basis weight of the nonwoven fabric 10 is not particularly limited, but is preferably 15 to 50 g / ^{m 2} the average value of the entire sheet, 20 to 40 g / ^{m 2} is more preferable.

The nonwoven fabric 10 demonstrated by the said embodiment has the following effects.
The nonwoven fabric 10 (see FIG. 1) has excellent cushioning properties.
Since the nonwoven fabric 10 of this embodiment has the part which protruded not only on the single side | surface of a front and back but on both surfaces, the cushioning characteristic peculiar to the structure is expressed. For example, streak-like projections or single-sided projections will inevitably exhibit elasticity as lines or surfaces. However, according to this embodiment, the two-dimensional movement is well followed and supported by points on both sides. Has a three-dimensional cushioning. In particular, when the nonwoven fabric includes the coiled fiber 1, the compression recovery of the shape is excellent as well as the cushioning property. Further, by having the fiber orientation oriented in the direction in which the wall portion 15 stands, a firm stiffness is produced in the wall portion 15 and the fiber has an appropriate cushioning property that prevents the fibers from being crushed in the thickness direction. . Furthermore, even if the nonwoven fabric 10 is crushed by receiving a pressing force due to the fiber orientation in the wall portion 15, 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 first and second projecting portions 11 and 12 are not easily crushed and can be easily recovered even if deformation occurs.
Since the space for temporarily holding the liquid can be secured by the action due to the above-mentioned good cushioning properties, the absorption speed can be maintained fast, and the pressure applied to the absorber is appropriately dispersed, so the amount of liquid returned from the absorber Is reduced. Moreover, since the shape restoring force is large, the stability of the absorption performance is also ensured.

The nonwoven fabric 10 (see FIG. 1) is excellent in touch.
The nonwoven fabric 10 of this embodiment has the 1st, 2nd protrusion parts 11 and 12 in a double-sided direction, and the top part 11T is rounded. Therefore, the surface on the 1st protrusion part 11 side is made into the skin surface side, and the favorable touch which a surface sheet contacts softly with respect to skin is implement | achieved. In addition, the point of contact with the pressure at the time of wearing increases and decreases in a planar shape, and the shape deformation of the entire topsheet against pressure can be suppressed while improving the touch, and shape restoration from pressure deformation can also be achieved Easy to do. There also exists an effect | action resulting from said favorable cushioning property, and a unique favorable touch is obtained with the dynamic effect | action by a point contact. Moreover, the point contact mentioned above has an effect also when excretion etc. are received, and the smooth touch is implement | achieved. Complementing this smooth touch (absorbing effect), since the fiber orientation is oriented in the direction in which the wall portion 15 stands up, the liquid is smoothened by the fibers oriented in the thickness direction of the wall portion 15. It flows along the fibers, quickly shifts from the second projecting portion 12 to the absorbent body disposed on the lower surface of the nonwoven fabric 10, and the liquid orientation of the wall portion 15 causes less liquid return, thereby realizing a smooth touch. Further, the nonwoven fabric 10 itself is excellent in air permeability by maintaining the above-described structure, and helps prevent fogging by the effect of point contact.

The nonwoven fabric 10 (see FIG. 1) is excellent in excretion capturing ability.
In the nonwoven fabric 10 of this embodiment, since it has internal space 11K and 12K inside each of the 1st, 2nd protrusion parts 11 and 12 which protrude on both surfaces, it is various according to the physical property of excretion liquid and excrement. These can be captured and dealt with in various forms. For example, when the first surface side Z1 of the nonwoven fabric 10 is described as the skin surface side, if it is excrement having high viscosity and low permeability, the excrement is temporarily stored in the internal space 12K without passing through the surface sheet of the nonwoven fabric 10. The water and a part thereof are absorbed by the absorber (not shown) through the second protrusion 12. On the other hand, if the excretory liquid has a low viscosity and is easily permeable, the liquid is mainly trapped in the internal space 11K after passing through the first protrusion 11. In any of these cases, the portion that first hits the skin surface is the first protruding portion top portion 11T, and the captured excretory fluid or excrement is made difficult to come into contact with the skin. As a result, after the excretion of urine, feces, menstrual blood, and spillage, a very good and smooth feeling can be sustained widely.

  Next, a preferred planar arrangement example of the first and second projecting portions 11 and 12 will be described with reference to FIG.

  As shown in FIG. 5, the example of arrangement | positioning is the 1st protrusion part 11 which protruded on the 1st surface side Z1 (paper surface upper side) of the side which planarly viewed the sheet-like nonwoven fabric, and the 1st surface side Z1 and the other side. The second projecting portion 12 projecting to the second surface side Z2 (downward on the paper surface) alternates in each of the first direction X and the second direction Y as different directions intersecting in plan view over the entire surface of the nonwoven fabric 10. Are arranged continuously. Accordingly, when viewed in one direction, the first projecting portions 11 and the second projecting portions 12 project alternately in opposite directions with respect to the sheet surface. The crossing angle between the first direction X and the second direction Y is preferably 30 ° or more and 90 ° (orthogonal) or less, for example, 90 °. The same number of second projecting portions 12 as the first projecting portions 11 projecting on the first surface side Z1 are arranged so as to project on the second surface side Z2. A portion between the first projecting portions 11 adjacent to each other is a first ridge portion 16. On the other hand, although not shown, the second ridge 17 is formed between the second protrusions 12 adjacent to each other when viewed from the second surface side Z2.

  The internal spaces 11K and 12K are separated by the wall portion 15 with the first ridge portion 16 and the second ridge portion 17 as a boundary, and are configured as spaces that are not substantially continuous. This “ridge portion” refers to a boundary line between two surfaces having an inclination and a convex section, and in this case, the first ridge portion 16 is an intersecting portion of the surface of the internal space 12K of the adjacent second protrusion 12. (Boundary line). In other words, along a ridge line that passes between the second protrusions 12 so as to surround the second protrusions 12 from the adjacent first protrusions 11 via the second protrusions 12 to another first protrusion 11B. Refers to the part. The “ridge line” is a line obtained by continuously connecting the highest positions in the vertical longitudinal section viewed continuously with respect to the line connecting the top portions 11T of the nearest first projecting portion 11. Say.

  In the nonwoven fabric 10 of the above-described arrangement example, the first protrusions 11 are connected via the first ridges 16, and the first protrusions 11 are parallel to the first ridges 16 while the first protrusions 11 are connected. It is connected through. Further, the second protrusions 12 are connected in parallel between the series of the first protrusions 11 and the series of other first protrusions 11. Since it is such an arrangement | positioning form, it has a capture | acquisition space (internal space 12K of a 2nd protrusion part) between the 1st protrusion parts 11 in a row. In addition, the capture space becomes a liquid transfer path, and the series of the first protrusions 11 prevents the liquid from leaking sideways. Note that the second protrusions 12 are also connected via the second ridges 17 on the second surface side Z2, and an internal space 11K is provided between the connections.

  In the above arrangement example, when the crossing angle between the first direction X and the second direction Y is 60 °, the first protrusions 11 and the second protrusions 12 are adjacent to each other. However, as long as a continuous sheet state is formed as a whole, the arrangement of such a form is also different in the first and second directions X and Y as the different directions intersecting in plan view. Since the second protrusions 11 and 12 are alternately and continuously arranged, it is included in the meaning that the first protrusions 11 and the second protrusions 12 are arranged “alternately”.

  As described above, the first protrusion 11 and the second protrusion 12 arranged in the first direction (X direction) and the second direction (Y direction) in plan view are in a state where the whole is continuous with a curved surface, The nonwoven fabric 10 is comprised. In addition, the arrangement | sequence form of the said 1st protrusion part 11 and the 2nd protrusion part 12 is not limited above, What is necessary is just a form which can be arrange | positioned by the arrangement | sequence which can be continued. For example, the arrangement may be such that six second projecting portions 12 are arranged at the apexes of the hexagon with the first projecting portion 11 as the center and the pattern extends in the plane. In addition, four second protrusions 12 are arranged at the apexes of the square with the first protrusion 11 as the center, and further, the second protrusions 12 are arranged at the centers between the apexes, for a total of eight second protrusions. 12 may be arranged, and the pattern may extend in the plane.

Next, a preferred embodiment of the method for producing the nonwoven fabric 10 will be described below with reference to FIG.
What is necessary is just to employ | adopt a general manufacturing method suitably for the manufacturing method of the above-mentioned nonwoven fabric 10. FIG.
As an example of a web-shaped support, a support 110 having the configuration shown in FIG. 6A is used. The support 110 has a large number of protrusions 111 corresponding to positions where the second protrusions 12 are shaped, and holes 112 are arranged corresponding to positions where the first protrusions 11 are shaped. Yes. That is, the support 110 has an uneven shape, and 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 X direction and the Y direction, respectively. It is arranged.
When a web (also referred to as a fiber web) 50 is arranged on the support 110 and the first hot air W1 is blown toward the web 50, as shown in FIG. The first protrusion 11 is shaped correspondingly, and the second protrusion 12 is shaped corresponding to the position of the protrusion 111. Accordingly, the first projecting portion 11 projecting to the first surface side Z1 on the side in plan view and having the internal space 11K, and the second projecting portion projecting to the second surface side Z2 opposite to the first surface side Z1 and having the internal space 12K. The protrusions 12 are alternately and continuously arranged in different X and Y directions intersecting in plan view, and the nonwoven fabric sheet 10 is shaped. In this case, the fiber density of the 1st protrusion part 11 shape | molded along the flow of the hot air W1 corresponding to the hole 112 becomes lower than the 2nd protrusion part 12 shape | molded corresponding to the processus | protrusion 111. FIG.
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.
In a manufacturing apparatus that supplies a web 50 before fusion to a shaping apparatus from a card machine (not shown) so as to have a predetermined basis weight, the web 50 is first transported and fixed on the support 110. Next, the first hot air W1 is blown onto the web 50 on the support 110 (the state shown in FIG. 6 (1)). Then, the web 50 is shaped so as to follow the shape of the support 110 (the state shown in FIG. 6B). The temperature of the first hot air W1 at this time varies depending on the type of fiber, the processing speed, the wind speed of the hot air, etc., considering a general fiber material used for this type of product. Therefore, it cannot be determined uniquely, but it is preferable to control the temperature around the melting point of the low melting point component of the fiber of the fiber web 50, preferably 80 ° C to 150 ° C, more preferably 100 ° C to 140 ° C. Control.
Moreover, although the wind speed of the 1st hot air W1 is based also on the height of the processus | protrusion 111 of the support body 110, it sets to 20-120 m / s from a viewpoint of a shaping property and a texture, More preferably, it is 40-80 m / s. set to s. When the wind speed is slower than this lower limit value, it will not be sufficiently shaped. If the wind speed exceeds this upper limit value, an opening will occur in the top portion 21T of the first projecting portion 21, and if it falls below the lower limit, shaping will be insufficient.
In this way, the fiber web 50 is shaped into an uneven shape.
In the case where the two-dimensional crimped fiber 2 and / or the latent crimpable fiber is composed of two or more kinds of resins and has a plurality of different melting points, the “melting point” The lowest melting point number is shown.

  Further, 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 to 20 mm, preferably 2 mm to 10 mm, and more preferably 3 mm to 7 mm.

  Next, as shown in FIG. 6 (3), the fibers 50 are fused by blowing the second hot air W2 at a temperature at which each fiber of the web 50 can be appropriately fused. The temperature of the second hot air W2 at this time is equal to or higher than the melting point of the low melting point component of the fiber of the fiber web 50, considering the general fiber material used in this type of product. It is preferable to control the temperature to be lower than the melting point of the high melting point component of the fiber of the fiber web 50. 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. . Specifically, it is preferably controlled to 100 ° C. or higher and 160 ° C. or lower, more preferably 120 ° C. or higher and 140 ° C. or lower. The wind speed is preferably 1 m / sec or more and 10 m / sec or less, more preferably 2 m / sec or more and 8 m / sec or less. If the wind speed of the second hot air W2 is too slow, heat cannot be transferred to the fibers, the fibers are not fused together, and the uneven shape is insufficiently fixed. On the other hand, if the wind speed is too high, the fiber will be too hot and the texture will tend to be poor. In the case where the coiled fiber 1 is formed by heat shrinking the latent crimpable fibers, the second crimped fibers W2 are sufficiently crimped by the first hot air W1. Is preferable from the viewpoint of the shapeability of the nonwoven fabric 10. Furthermore, you may give the 3rd hot air W3 as needed.

  The third hot air W3 (not shown) has a wind speed slower than the wind speed of the first hot air W1, and the wind speed at which the fuzzy fibers of the fiber web 50 are pressed against the net surface (not shown) to lie down. To do. Specifically, it is preferably 1.0 m / sec or more and 5 m / sec or less. If the wind speed of the third hot air W3 is too slow, the fuzzy fibers cannot be fused, and the reduction of the fuzz becomes insufficient. On the other hand, if the wind speed is too high, the thickness of the nonwoven fabric becomes small due to the wind pressure, and since the fibers are heated in that state, fusion of fibers other than the fluffy fibers often occurs, resulting in a decrease in thickness, touch and liquid permeability. Becomes insufficient. Therefore, the wind speed of the 3rd hot air W3 shall be said range, More preferably, you may be 1 m / sec or more and 2 m / sec or less.

In the above manufacturing method, it is preferable that the protrusions 111 of the support 110 are substantially solid. Moreover, the support body 110 is not configured by knitting a wire, but a support body having no joints is preferably used. Accordingly, the fibers do not get into the protrusions 12 and become entangled, and the fibers are not caught in a part of the support 110 such as between the protrusions 12. Further, by using the support, the blown hot air W1 is less likely to bounce on the surface of the support or to be disturbed when passing through the support, and the flow toward the hole 112 is good. As a result, the constituent fibers, particularly the coiled fibers 1 converge toward the hole 112 and are oriented in the standing direction of the wall 15 at any location of the wall 15. Here, the term “substantially solid” as used herein refers to a state in which the fibers do not enter even if the structure is densely packed or there is a void to such an extent that the fibers do not enter.
On the other hand, in the support body in which the wire rod is knitted into a net shape, since the protrusion is not solid, hot air W1 is wound inside the net, and the fiber orientation of the wall portion is in the width direction (CD) or The thing which becomes non-orientation comes out and the orientation of the nonwoven fabric of this invention cannot be obtained. Moreover, when giving a hollow by embossing etc. with respect to the nonwoven fabric which the fiber has already melt | fused like the conventional, the orientation of the fiber remains suitable for MD, and it is set as orientation like the nonwoven fabric of this invention. Can not. That is, in the case of conventional embossing or the like, the fibers in the wall portion in the MD cross section of the depression are oriented in the standing direction, but in the CD section, the fibers are oriented in a direction perpendicular to the standing direction. turn into.
Accordingly, the nonwoven fabric of the present invention is preferably manufactured using the above-mentioned integral and seamless support having substantially solid protrusions.

  In addition, it is preferable that the web 50 contains 30 mass%-100 mass% of thermoplastic fibers. The web 50 may include fibers that do not inherently have heat-fusibility (for example, natural fibers such as cotton and pulp, rayon, and acetate fibers).

The nonwoven fabric sheet 10 is produced through the above steps.
In the manufacturing method, considering continuous production, the manufacturing apparatus (not shown) is a conveyor type or drum type capable of transporting the support 110, and the conveyed nonwoven fabric sheet 10 is fixed. The mode which winds up with a roll (not shown) is mentioned.

  In the above manufacturing method, the thickness of each sheet is appropriately determined depending on the height of the protrusion 111 and the wind speed. For example, when the height of the protrusion 111 is increased, the thickness of the sheet is increased, and when it is decreased, the thickness of the sheet is decreased. On the other hand, when the wind speed is increased, the thickness of the sheet is increased, and when the wind speed is decreased, the thickness of the sheet is decreased. Further, when the height of the protrusion 111 is increased, the fiber density of the sheet is decreased, and when it is decreased, the fiber density of the sheet is increased. On the other hand, when the wind speed is increased, the fiber density of the sheet is decreased, and when the wind speed is decreased, the fiber density of the sheet is increased.

  The nonwoven fabric 10 of the present invention can be used for various other applications. For example, it can be suitably used as a surface sheet of absorbent articles such as disposable diapers, sanitary napkins, panty liners, urine absorption pads and the like. Furthermore, since the both surfaces of the nonwoven fabric 10 are excellent in air permeability, liquid diffusibility, deformation characteristics at the time of pressing force, etc. due to the concavo-convex structure, between the surface sheet such as diapers and sanitary products and the absorbent body It can also be used as a sub-layer interposed between them, an absorbent covering sheet (core wrap sheet), and the like. In addition, the form utilized as a surface sheet, gathers, an exterior sheet, and a wing of an absorbent article is also mentioned. Furthermore, the form utilized as a covering sheet | seat of a wiping wipe sheet | seat, a cleaning sheet | seat, a filter, and a heating tool is also mentioned. The following nonwoven fabric is further disclosed regarding the embodiment mentioned above.

<1> A first projecting portion projecting on the first surface side of the sheet-like nonwoven fabric in plan view and having an internal space, and a second projecting surface projecting on the second surface side opposite to the first surface side and having an internal space. 2 protrusions, and the first and second protrusions are alternately and continuously arranged in different directions intersecting in plan view of the nonwoven fabric, and the first protrusions and the second protrusions. A nonwoven fabric in which a part is integrated with a wall part and contains a coiled fiber.

<2> The nonwoven fabric according to <1>, wherein the coiled fibers present in the wall are oriented in the sheet thickness direction of the nonwoven fabric.
<3> The nonwoven fabric according to <1> or <2>, wherein the coiled fibers present in the wall are oriented in a standing direction of the wall.
<4> The nonwoven fabric according to <1> or <2>, wherein the coiled fibers present in the wall portion are oriented in a direction connecting the first protruding portion and the second protruding portion of the nonwoven fabric.
<5> The nonwoven fabric according to any one of <1> to <4>, wherein the coiled fiber is an actual crimped fiber.
<6> The nonwoven fabric according to <5>, wherein the coiled fiber is an actual crimped fiber, and is a core-sheath composite fiber that is a combination of polyethylene and polypropylene.
<7> The nonwoven fabric according to <5> or <6>, wherein the content ratio of the actual crimped fiber to the entire constituent fibers of the nonwoven fabric is 10% or more and 100% or less.
<8> The nonwoven fabric according to <5> to <7>, wherein the content of the actual crimped fiber with respect to the entire constituent fibers of the nonwoven fabric is 30% to 50%.
<9> The nonwoven fabric according to any one of <1> to <4>, wherein the coiled fiber is a latent crimped fiber.
<10> The nonwoven fabric according to <9>, wherein the coiled fiber is a latent crimped fiber that is a combination of polyethylene and polypropylene.
<11> The nonwoven fabric according to <9> or <10>, wherein the content of the latent crimped fiber with respect to the entire constituent fibers of the nonwoven fabric is 10% or more and 30% or less.
<12> The nonwoven fabric according to any one of <9> to <11>, wherein a content ratio of the latent crimped fiber to the entire constituent fibers of the nonwoven fabric is 20% or more and 30% or less.
<13> The coiled fiber present in the wall portion preferably has an orientation angle of 40 ° or more and 140 ° or less, more preferably 50 ° or more and 130 ° or less with respect to the horizontal plane of the nonwoven fabric sheet. 12> The nonwoven fabric according to any one of the above.
<14> The nonwoven fabric contains the coiled fiber and a two-dimensional crimped fiber, and the two-dimensional crimped fiber is oriented in the sheet thickness direction of the nonwoven fabric at the top of the first protruding portion <1. > To <13> The nonwoven fabric according to any one of the above.
<15> The nonwoven fabric according to any one of <1> to <14>, wherein the entire constituent fiber including the coiled fiber has a fiber orientation in a standing direction of the wall portion in the wall portion.
<16> The nonwoven fabric includes the coiled fiber and a two-dimensional crimped fiber, and a fiber obtained by incorporating a part of the two-dimensional crimped fiber into the coiled fiber at the top of the first protruding portion. The nonwoven fabric according to any one of <1> to <15>, in which there is an aggregate, and the two-dimensional crimped fibers in the fiber aggregate are erected with respect to the longitudinal direction of the coiled fiber.
<17> The two-dimensional crimped fiber in the fiber assembly in the first protrusion is preferably 40 ° or more and 140 ° or less, more preferably 50 ° or more and 130 ° or less with respect to the horizontal plane of the nonwoven fabric sheet. The nonwoven fabric according to any one of <1> to <16>.

  EXAMPLES Hereinafter, although this invention is demonstrated further in detail based on an Example, this invention is limited and interpreted by these Examples.

[Example 1-6]
In Example 1, a 2.3 dtex × 51 mm core-sheath composite fiber having a polypropylene core and a sheath made of polyethylene is used as a potential crimpable fiber, and a core is polyethylene terephthalate and a sheath is used as a two-dimensional crimped fiber. The nonwoven fabric test body c1 was produced using the 2.4 dtex * 51mm core-sheath-type composite fiber which consists of polyethylene.
First, the carding machine was supplied to the shaping device so that the basis weight was 30 g / m ² at a mixing ratio of 10% of the latent crimpable fiber and 90% of the two-dimensional crimped fiber. In the shaping apparatus, the fiber web was fixed on a support 110 having a large number of protrusions 111 and having air permeability. The MD pitch in the plan view of the protrusion 111 of the support 110 was 8 mm, the CD pitch was 4 mm, and the height of the protrusion 111 was 3.5 mm. Further, the hole diameter of the hole 112 in the support 110 was set to 28 mm. Next, the first hot air W1 (temperature 130 ° C., wind speed 50 m / s) was blown onto the fiber web 50 on the support 110, and the fiber web 50 was shaped along the protrusions 111 on the support 110. Next, the shape was fixed by fusing the fibers of each core-sheath structure by switching to the second hot air W2 at a temperature of 135 ° C. and a wind speed of 5 m / s. Next, the shaped nonwoven fabric was taken out and third hot air W3 (temperature 139 ° C., wind speed 1.5 m / sec) was blown to produce a nonwoven fabric specimen.
The nonwoven fabric shaped by heat sealing in this manner was taken out and used as a nonwoven fabric test body c1 of Example 1.
The basis weight of the nonwoven fabric test body c1 of Example 1 was 30 g / m ² , and the thickness T was 3.0 mm. The orientation angle of the coiled fiber in the wall portion was 58 °, and the orientation strength was 1.65. Further, the orientation angle of the two-dimensional crimped fiber taken into the coiled fiber at the top of the first protrusion was 64 °, and the orientation strength was 1.36. The orientation angle of the coiled fiber in the wall and the orientation angle of the two-dimensional crimped fiber near the top of the first protrusion are based on the above-described <Measurement Method of Fiber Orientation (Orientation Angle, Orientation Strength)>. It was measured. The wall portion is measured based on a photographed image printed at 100 times (see FIG. 7), and the first protrusion is measured based on a photographed image printed at 70 times magnification (see FIG. 8). did. Hereinafter, it measured similarly in Examples 2-6. In FIGS. 7 and 8, a part of the coiled fiber or two-dimensional crimped fiber is traced with a dotted line, and the orientation of the fiber is shown for convenience.

In Example 2, the non-woven fabric specimen c2 was subjected to the same conditions as in Example 1 except that the latent crimpable fiber used in Example 1 was mixed at 20% and the two-dimensional crimped fiber was mixed at 80%. Produced.
The basis weight of the nonwoven fabric test body c2 of Example 2 was 31 g / m ² , and the thickness T was 2.5 mm. And the orientation angle | corner of the coiled fiber in a wall part was 64 degrees, and the orientation intensity | strength was 1.48. The orientation angle of the two-dimensional crimped fiber taken into the coiled fiber at the top of the first protrusion was 40 °, and the orientation strength was 1.33.

In Example 3, the nonwoven fabric specimen c3 was prepared under the same conditions as in Example 1 except that the latent crimpable fiber used in Example 1 was mixed at 30% and the two-dimensional crimped fiber at 70%. Produced.
The basis weight of the nonwoven fabric test body c3 of Example 3 was 29 g / m ² , and the thickness T was 2.2 mm. The orientation angle of the coiled fiber in the wall portion was 62 °, and the orientation strength was 1.52. Further, the orientation angle of the two-dimensional crimped fiber taken into the coiled fiber at the top of the first protrusion was 41 °, and the orientation strength was 1.25.

Example 4 uses a core-sheath type composite fiber of 2.3 dtex × 51 mm in which the core is polypropylene and the sheath is made of an ethylene-propylene random copolymer as the potential crimpable fiber. %, A non-woven fabric specimen c4 was produced under the same conditions as in Example 1 except that the mixing ratio of the two-dimensional crimped fiber used in Example 1 was 90%.
The basis weight of the nonwoven fabric test body c4 of Example 4 was 30 g / m ² , and the thickness T was 2.5 mm. The orientation angle of the coiled fiber in the wall portion was 41 ° and the orientation strength was 1.23. In addition, the orientation angle of the two-dimensional crimped fiber taken into the coiled fiber at the top of the first protrusion was 71 °, and the orientation strength was 1.30.

Example 5 uses the same crimped fiber as in Example 4 as the latent crimpable fiber, 20% of the latent crimpable fiber, and 80% of the two-dimensional crimped fiber used in Example 1 A nonwoven fabric specimen c5 was produced under the same conditions as in Example 1 except that.
The basis weight of the nonwoven fabric test body c5 of Example 5 was 33 g / m ² , and the thickness T was 2.2 mm. The orientation angle of the coiled fiber in the wall portion was 45 °, and the orientation strength was 1.40. Further, the orientation angle of the two-dimensional crimped fiber taken into the coiled fiber at the top of the first protrusion was 77 °, and the orientation strength was 1.47.

Example 6 uses the same crimped fiber as in Example 4 as the latent crimpable fiber, 30% of the latent crimpable fiber, and 70% of the two-dimensional crimped fiber used in Example 1 A nonwoven fabric specimen c6 was produced under the same conditions as in Example 1 except that.
The basis weight of the nonwoven fabric test body c6 of Example 6 was 33 g / m ² , and the thickness T was 2.0 mm. The orientation angle of the coiled fiber in the wall portion was 95 °, and the orientation strength was 1.46. Further, the orientation angle of the two-dimensional crimped fiber taken into the coiled fiber at the top of the first protrusion was 56 °, and the orientation strength was 1.27.

In Example 7, as the actual crimpable fiber, a core having a polypropylene and a sheath having a polyethylene is used. The actual crimpable fiber is 30%, and the two-dimensional crimped fiber used in Example 1 is a mixing ratio of 70%. A non-woven fabric specimen c7 was produced under the same conditions as in Example 1 except that the second hot air W2 was changed to 145 °.
The basis weight of the nonwoven fabric test body c7 of Example 7 was 30 g / m ² , and the thickness T was 3.7 mm. The orientation angle of the coiled fiber in the wall portion was 75 ° and the orientation strength was 1.24. Further, the orientation angle of the two-dimensional crimped fiber taken into the coiled fiber at the top of the first protrusion was 63 °, and the orientation strength was 1.31.

In Example 8, the same crimped fibers as in Example 7 were used, the actual crimpable fibers being 0%, and the two-dimensional crimped fibers used in Example 1 having a mixing ratio of 50%. Except for the above, a nonwoven fabric specimen c8 was produced under the same conditions as in Example 7 above.
The basis weight of the nonwoven fabric test body c8 of Example 8 was 30 g / m ² , and the thickness T was 4.0 mm. The orientation angle of the coiled fiber in the wall portion was 92 ° and the orientation strength was 1.24. Further, the orientation angle of the two-dimensional crimped fiber taken into the coiled fiber at the top of the first protrusion was 40 °, and the orientation strength was 1.10.

In Example 9, the same crimped fiber as in Example 7 was used, and the actual crimpable fiber was 70% and the two-dimensional crimped fiber used in Example 1 was mixed at 30%. Except for the above, a nonwoven fabric test body c9 was produced under the same conditions as in Example 7 above.
The basis weight of the nonwoven fabric test body c9 of Example 7 was 30 g / m ² , and the thickness T was 4.1 mm. The orientation angle of the coiled fiber in the wall portion was 82 °, and the orientation strength was 1.07. In addition, the orientation angle of the two-dimensional crimped fiber taken into the coiled fiber at the top of the first protrusion was 40 °, and the orientation strength was 1.23.

In Example 10, a non-woven fabric specimen c10 was produced under the same conditions as in Example 7 except that the actual crimpable fiber was the same as in Example 7 and the actual crimpable fiber was 100%. .
The basis weight of the nonwoven fabric test body c10 of Example 7 was 29 g / m ² , and the thickness T was 3.9 mm. The orientation angle of the coiled fiber in the wall portion was 97 ° and the orientation strength was 1.11.

[Comparative Examples 1 and 2]
In Comparative Example 1, 30% of rayon fibers and heat-shrinkable fibers made of an ethylene-propylene copolymer were mixed at a ratio of 70%, hydroentangled and then dried to prepare a multi-woven nonwoven fabric test body c3. The basis weight was 105 g / m ² and the thickness T was 1.4 mm.

In Comparative Example 2, a non-woven fabric having pores was produced in the same manner as in Example 1 of JP-A-03-137258. Specifically, it is as follows.
A web composed of polyethylene terephthalate-polyethylene core-sheath fiber 2.4 dtex × 51 mm was formed by a conventional carding machine. Next, the web was sandwiched between an uneven net having air permeability and a plain weave net, and air was jetted from the plain weave net side. And the web in which the density part of the fiber was formed in the predetermined pitch was produced by pushing a web into the recessed part of the said uneven | corrugated net. Thereafter, the web in this state was passed through heated air at 140 ° C., and the polyethylene part was welded to integrate the web. Thereby, the uneven | corrugated state was formed with the predetermined pitch, and the nonwoven fabric test body c2 which was opened to the concave part was produced. The basis weight of the nonwoven fabric test body s2 was 28 g / m ² , and the thickness T was 5.5 mm.

  Next, the evaluation method will be described. The following measurement test was performed using a nonwoven fabric test body or a diaper.

<Measurement of basis weight>
The basis weight of each nonwoven fabric specimen was measured by the following method. First, the nonwoven fabric test body was cut into a size of 250 mm × 200 mm, and this was used as a measurement piece. The measurement piece was placed on an electronic balance (regardless of manufacturer). The weight in this state was measured, and the weight was divided by the area to obtain the basis weight (g / m ² ). As measured values, three points were measured and the average value was adopted.

<Measurement of sheet thickness (TS)>
Using a KES compression tester (KES FB-3, manufactured by Kato Tech Co., Ltd.), each nonwoven fabric test specimen was evaluated for compression characteristics up to 5.0 × 10 ³ Pa in the normal mode, and at a minute pressure (0. The thickness (T) of 05 × 10 ³ Pa) was read from the chart. As measured values, three points were measured and the average value was adopted.

<Measurement of strike-through>
The liquid strike-through indicates the time (seconds) required for a predetermined amount of physiological saline to pass from the front surface to the back surface of the sheet. Measured based on a test method “153.0-02 REPEATED LIQUID STRIKE-THROUGH TIME” defined by EDANA (European Disposables And Nonwovens Association) using a tester LISTER (trade name) manufactured by LENZING . The measured value is preferably 3.0 seconds or less, and more preferably 2.0 seconds or less.
A: 1.0 second or less B: 2.0 seconds or less C: 4.0 seconds or less D: 5.0 seconds or more

<Measurement of cushioning properties>
Using a KES compression tester (KES FB-3, manufactured by Kato Tech Co., Ltd.), each nonwoven fabric specimen was evaluated for compression properties up to 5.0 × 10 ³ Pa in the normal mode, and 5 × 10 at the time of return. The thickness at the time of ³ Pa pressurization was read from the chart, and the value was divided from the sheet thickness TS to evaluate the cushioning property. As measured values, three points were measured and the average value was adopted. The higher the value, the better the cushioning properties. However, when the value is 50% or more, the cushioning properties are impaired. Therefore, the numerical value is preferably 20 to 50%.
A: 30-50%
B: 20-29%
C: 19% or less D: 51% or more

  Table 1 shows the measurement results and evaluation results for each of the above evaluation items. The numerical value shown in the “Strike-through” column is the time (seconds) required for the physiological saline to pass, as measured by the above measurement method. The numerical value shown in the column of “cushion property” is a numerical value (%) measured by the above measuring method.

  As is clear from the evaluation results shown in Table 1, the nonwoven fabric test specimens c1 to c10 of Examples 1 to 10 are B or A in all items of strike-through and cushioning properties, and do not have coiled fibers. It can be seen that it is superior to the nonwoven fabric specimens s1 and s2 of Examples 1 and 2. That is, it can be seen that the nonwoven fabric test samples c1 to c10 of Examples 1 to 10 have good cushioning properties and excellent liquid permeability as well as liquid trapping properties.

DESCRIPTION OF SYMBOLS 1 Coiled fiber 2 Two-dimensional crimped fiber 3 Fiber assembly 10 Nonwoven fabric 11 1st protrusion part 11T 1st protrusion part top part 11K Internal space 11H Opening part 12 2nd protrusion part 12T 2nd protrusion part top part 12K Internal space 12H Opening part 15 Wall portion 16 First ridge portion 17 Second ridge portion Z1 First surface side Z2 Second surface side

Claims (6)

A first projecting portion projecting on the first surface side of the sheet-like nonwoven fabric in plan view and having an internal space, and a second projecting portion projecting on the second surface side opposite to the first surface side and having an internal space The first and second protrusions are alternately and continuously arranged in different directions intersecting in plan view of the nonwoven fabric, and the first protrusions and the second protrusions are are integrated in the walls, it contains a coiled fiber, the coiled fibers present in the wall portion, that are oriented in the sheet thickness direction of the nonwoven fabric nonwoven fabric. The coiled fibers are apparently crimping fiber of claim 1, wherein the non-woven fabric. The nonwoven fabric according to claim 2 , wherein a content ratio of the manifest crimped fibers to the entire constituent fibers of the nonwoven fabric is 10% or more and 100% or less. The coiled fiber is a potential crimping fiber, according to claim 1, wherein the non-woven fabric. The nonwoven fabric according to claim 4 , wherein the content of the latently crimped fibers with respect to the entire constituent fibers of the nonwoven fabric is 10% or more and 30% or less. The non-woven fabric contains the coiled fiber and a two-dimensional crimped fiber, and a fiber assembly formed by incorporating a part of the two-dimensional crimped fiber into the coiled fiber at the top of the first protruding portion. The nonwoven fabric according to any one of claims 1 to 5 , wherein the two-dimensional crimped fibers in the fiber assembly are erected with respect to the longitudinal direction of the coiled fibers.