Method for manufacturing nonwoven fabric

Abstract

To provide a method for manufacturing a nonwoven fabric having appropriate compression energy and excellent feeling despite a bulky and thick structure thereof.SOLUTION: A method for manufacturing a nonwoven fabric comprises: a first shaping step to shape an unwelded web formed of aggregate containing fibers by engaging a support body having convex or concavity with a first push-in member having a push-in part engageable with the support body; a second shaping step to shape the shaped unwelded web by engaging the support body with a second push-in member having a push-in part engageable with the support body; and a heat treatment step to apply a fiber fusing by heated fluid, or either an embossing press bonding or an embossing fusing in the second shaping step or after the second shaping step. A difference between an angle in engaging direction of the push-in part of the first push-in member with respect to a machine flow direction of the support body and an angle in engaging direction of the push-in part of the second push-in member with respect to the machine flow direction of the support body is 60 degrees or more and 90 degrees or less.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a method for producing a nonwoven fabric. [Background technology]

[0002] Conventionally, nonwoven fabrics have been provided with various types of uneven shapes, and manufacturing methods for providing such uneven shapes have been developed.

[0003] For example, Patent Document 1 describes a technique in which a nonwoven fabric is laminated on an unfused web that has been shaped into unevenness by the meshing of rolls having unevenness, and then the unevenness is further shaped. The three-dimensionally shaped nonwoven fabric obtained by this technique has a two-layer structure with a closed hollow structure in which the inside of the protrusions of the surface fiber layer is hollow and a back fiber layer is laminated on the back side of the surface fiber layer. Patent Document 2 describes a method for producing a nonwoven fabric by pressing a pressing part into an unfused fiber web on a textured support to form the web, and then laminating another unfused fiber web on the web. The nonwoven fabric thus obtained has a textured structure with unevenness.

[0004] Patent Document 3 describes a technique for forming a composite sheet by joining a first sheet and a second sheet made of a nonwoven fabric containing a resin material while shaping them by engaging two uneven rolls with heating. In the composite sheet obtained by this technique, the second sheet has a protrusion only in the center of the region corresponding to the curved portion of the first sheet, and has a shape surrounded by a flat portion.

[0005] Patent Documents 4 and 5 describe a technique for forming an uneven shape on an unfused web by blowing hot air onto the web. In the nonwoven fabric obtained by this method, fiber orientation in the thickness direction is obtained in the unevenly formed portion of the unfused web. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent Publication No. 2021-037057 [Patent Document 2] JP 2019-112747 A [Patent Document 3] JP 2019-063581 A [Patent Document 4] JP 2016-089289 A [Patent Document 5] JP 2014-012913 A Summary of the Invention [Problem to be solved by the invention]

[0007] In the above-mentioned various nonwoven fabric manufacturing methods, the thickness of the nonwoven fabric can be increased by forming the unevenness, and it is possible to impart a bulky and soft texture and good cushioning properties at the convex parts. On the other hand, from the viewpoint of improving the cushioning properties, it has become necessary to make the convex parts more difficult to collapse even when pressed from the side or obliquely. In this regard, if the collapse resistance of the convex parts is realized by increasing the amount of fiber, this may lead to rigidity depending on the amount of fiber, and may actually impair the bulky and soft texture. Therefore, a manufacturing method that can further improve the collapse resistance of the convex parts without impairing the soft texture by forming the unevenness has been studied. However, in the manufacturing methods of nonwoven fabrics described in Patent Documents 4 and 5, the convex portions are formed as independent portions without being connected to each other by hot air, and it is difficult to further improve the self-supporting property of the convex portions. In addition, in the manufacturing method of nonwoven fabrics described in Patent Document 1, the rolls are engaged with each other to form mutually independent convex portions in a staggered pattern, as described above. In the manufacturing method of nonwoven fabrics described in Patent Document 3, only the embossed portions that become the bottoms around the convex portions after the nonwoven fabric is made are fused. No interlayer fusion is performed around the embossed portions, and there is no description of a technique for further improving the collapse resistance of the convex portions. In the method for producing a nonwoven fabric described in Patent Document 2, a vertical rib extending in one direction and a horizontal rib supporting the vertical rib in a direction intersecting the vertical rib are formed by an interlocking shaping process using a support and a pushing member. However, there is no description of process control for further increasing the strength of the support between the vertical rib and the horizontal rib in the interlocking shaping process.

[0008] In view of the above, the present invention relates to a method for producing a nonwoven fabric that has a bulky and thick structure, yet has an appropriate compression energy and is excellent in feel. [Means for solving the problem]

[0009] The present invention provides a method for producing a nonwoven fabric, comprising a first shaping step of shaping an unfused web consisting of an aggregate containing fibers by engaging a support having a convex or concave portion with a first pushing member having a pushing portion capable of engaging with the support, a second shaping step of shaping the shaped unfused web by engaging the support with a second pushing member having a pushing portion capable of engaging with the support, and a heat treatment step of fiber fusion with a heated fluid, or embossing or fusion in the second shaping step or after the second shaping step, wherein the difference between the angle of the meshing direction of the pushing portion of the first pushing member relative to the machine flow direction of the support and the angle of the meshing direction of the pushing portion of the second pushing member relative to the machine flow direction of the support is 60 degrees or more and 90 degrees or less. As an example of the nonwoven fabric obtained, a concave-convex nonwoven fabric in which the positions of the convex portions and the concave portions on the front and back coincide with each other is obtained.

[0010] The present invention also provides a method for producing a nonwoven fabric, comprising: a first shaping step of shaping a first unfused web consisting of an aggregate containing fibers by engaging a support having convex or concave portions with a first pushing member having a pushing portion capable of engaging with the support; a second shaping step of laminating a second unfused web on the shaped first unfused web on the support, and shaping the web from the second unfused web side by engaging the support with a second pushing member having a pushing portion capable of engaging with the support; and a heat treatment step of fiber fusion using a heated fluid, or embossing or embossing during or after the second shaping step, wherein the difference between the angle of the engaging direction of the pushing portion of the first pushing member relative to the machine flow direction of the support and the angle of the engaging direction of the pushing portion of the second pushing member relative to the machine flow direction of the support is 60 degrees or more and 90 degrees or less. As an example of the nonwoven fabric obtained, a concave-convex nonwoven fabric having hollows in the convex portions or a concave-convex nonwoven fabric having a solid structure in the convex portions can be obtained. Effect of the Invention

[0011] According to the method for producing a nonwoven fabric of the present invention, a nonwoven fabric having a bulky and thick structure, moderate compression energy, and excellent texture can be suitably produced. The "bulk" referred to here is also called bulk density, and is indicated by the fiber density of the entire nonwoven fabric. The fiber density decreases as the gaps between the fibers in the nonwoven fabric increase, and the lower the fiber density, the higher the bulk. The "compression energy" refers to the product of the deformation amount when compressing the nonwoven fabric in the thickness direction and the force required for the compression. Moderate compression energy results in an excellent texture. In this regard, in conventional nonwoven fabrics, the lower the fiber density (the higher the bulk), the lower the compression energy tends to be. If the compression energy is too low, the fabric tends to feel unreliable, and if it is too high, the fabric tends to feel hard. In contrast, according to the method for producing a nonwoven fabric of the present invention, a nonwoven fabric that has a bulky and thick structure, has a moderate compression energy, is likely to generate a suitable repulsive force when compressed, and has an excellent texture can be suitably produced. [Brief description of the drawings]

[0012] [Figure 1] 1(A) and 1(B) are plan views that diagrammatically show an example of the angle of the meshing direction in two shaping steps carried out in the method for producing a nonwoven fabric of the present invention. [Diagram 2] 13 is a plan view showing an example of an engagement direction when the pusher member is not continuous. FIG. [Diagram 3] 13(A) and 13(B) are plan views showing a case where the meshing direction is in two directions, the machine direction and the width direction. [Figure 4] 10 is an explanatory diagram illustrating a schematic view of an even gap and an amount of meshing between a support body and a push-in member in a meshed state. FIG. [Diagram 5] 1(A) to 1(D) are explanatory views showing a schematic example of a two-stage shaping process. [Figure 6] FIG. 2 is a plan view showing a schematic view, from the surface side, of an example of an arrangement of protrusions and bottoms provided on a nonwoven fabric obtained by the nonwoven fabric manufacturing method of the present invention. [Figure 7] FIG. 7 is an MD-projected cross-sectional view that illustrates a cross section along line II in the case where the nonwoven fabric shown in FIG. 6 is obtained by the nonwoven fabric manufacturing method of the first embodiment. [Figure 8] 7 is a CD-projected cross-sectional view that illustrates a cross section taken along line II-II in the case where the nonwoven fabric shown in FIG. 6 is obtained by the nonwoven fabric manufacturing method of the first embodiment. FIG. [Figure 9] FIG. 7 is an MD-projected cross-sectional view illustrating a cross section along line III-III in the case where the nonwoven fabric illustrated in FIG. 6 is obtained by the nonwoven fabric manufacturing method according to the first embodiment. [Figure 10] 7 is a projected cross-sectional view that typically shows a cross section taken along line IV-IV in the case where the nonwoven fabric shown in FIG. 6 is obtained by the nonwoven fabric manufacturing method of the first embodiment. FIG. [Figure 11] 10 is a plan view showing another example of the arrangement of the protrusions and bottoms of the nonwoven fabric as viewed from the front side. FIG. [Figure 12]FIG. 7 is an MD-projected cross-sectional view that typically shows a cross section along line II in the case where the nonwoven fabric shown in FIG. 6 is obtained by a method for producing a nonwoven fabric according to a second embodiment. [Figure 13] 7 is a CD-projected cross-sectional view typically showing a cross section taken along line II-II in the case where the nonwoven fabric shown in FIG. 6 is obtained by a nonwoven fabric manufacturing method according to a second embodiment. FIG. [Figure 14] FIG. 7 is an MD-projected cross-sectional view illustrating a cross section along line III-III in the case where the nonwoven fabric illustrated in FIG. 6 is obtained by the nonwoven fabric manufacturing method according to the second embodiment. [Figure 15] 7 is a projected cross-sectional view that typically shows a cross section taken along line IV-IV in the case where the nonwoven fabric shown in FIG. 6 is obtained by a method for producing a nonwoven fabric according to a second embodiment. FIG. [Figure 16] FIG. 11 is a cross-sectional view used when measuring the wall portion at the uppermost convex portion. [Figure 17] FIG. 1 is a schematic diagram showing an example (Specific Example 1) of a preferred manufacturing apparatus used in the manufacturing method of the nonwoven fabric of the present invention. [Figure 18] FIG. 2 is a schematic diagram showing another example (Specific Example 2) of a preferred manufacturing apparatus used in the manufacturing method of the nonwoven fabric of the present invention. [Figure 19] 1 is a schematic plan view of a nonwoven fabric sample produced by a method for producing a nonwoven fabric according to an embodiment of the present invention, and a photograph showing the state of a fiber layer in a cross section thereof. [Figure 20] FIG. 4 is an explanatory diagram showing measurement positions of the wall fiber orientation degree. [Figure 21] FIG. 2 is a cross-sectional view showing a schematic diagram of various area ratios in the nonwoven fabric of the present invention. [Figure 22] 1 is a photograph substituting a drawing showing the state of fibers in the cross section of nonwoven fabric samples produced by the nonwoven fabric producing methods of Example and Comparative Examples 1 to 3. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] A preferred embodiment of the method for producing a nonwoven fabric of the present invention will be described with reference to the drawings.

[0014] In the method for producing a nonwoven fabric of the present invention, various terms are defined as follows. The "support" has an uneven shape, can be engaged with a pushing member, and temporarily holds the nonwoven fabric or the unfused web. The above-mentioned convex and concave portions refer to portions that have a relative height difference with respect to the substrate, and for example, a portion that protrudes higher than the substrate constituting the support is a convex portion. In this case, the substrate portion sandwiched between the convex portions can also be said to be a concave portion. In addition, if the substrate constituting the support has a partially recessed portion, that portion becomes a concave portion. In this case, the substrate portion sandwiched between the concave portions can also be said to be a convex portion. The support may be flexible, such as in the form of a conveyor or net, or non-flexible, such as in the form of a drum roll or plate. Various materials can be used for the support. For example, resin, metal, carbon, and ceramic can be mentioned. A non-flexible embossing roll is preferable in that it can be embossed heat fusion or embossed pressure bonding on the support. The "pushing member" has an uneven shape and can be pushed into (engaged with) the support. The pushing member may be flexible or inflexible, and examples thereof include a ring-shaped roll, an uneven roll, a net, a belt, a chain, a leaf spring (elastic plate-like body), a movable load plate, and a flexible blade incorporated into a support part. Various materials can be used for the pushing member, and examples thereof include resin, metal, carbon, and ceramic.

[0015] "Interlocking" means that the concave portion of the support and the pushing portion of the pushing member are arranged to correspond to each other, and the pushing portion enters the concave portion while leaving a gap between the convex portion of the support and the pushing portion of the pushing member to allow the web to enter. In other words, it means that the concave and convex shapes of the support and the pushing member are matched so as to interlock. At this time, in order to reduce wear and deformation of the support and the pushing member, it is preferable that the support and the pushing member do not come into direct contact with each other by interposing an unfused web therebetween.

[0016] The "machine flow direction" is the direction in which the manufacturing process proceeds in sequence, and is the direction in which the web to be processed is transported. If the support is, for example, a roll, it is the direction in which the roll rotates. It is also called MD (Machine Direction). The "width direction" is a direction perpendicular to the machine flow direction and along the width of the unfused web. When the support is a roll, for example, the width direction is the roll axial direction. It is also called CD (Cross Direction).

[0017] The term "web" refers to a sheet-like fiber assembly including nonwoven fabrics and unfused webs. The web preferably contains thermoplastic fibers as constituent fibers. The term "nonwoven fabric" refers to a sheet in which a fiber assembly is formed by thermal fusion, mechanical entanglement, or chemical bonding (adhesive, chemical bond, etc.). "Unfused web" means an aggregate of unfused fibers that can be fused by heat (hot air, steam, heat embossing, ultrasonic embossing, etc.), and excludes nonwoven fabrics that have been mechanically entangled by hydroentanglement or needle punching before the fusion treatment process. More specifically, an unfused web is one that does not have the strength of a nonwoven fabric and has a maximum tensile strength of 100cN / 50mm or less in the MD and CD directions. For example, this includes carded webs.

[0018] The "thermally fused" state means that the unfused web melts, and the constituent fibers of the web in the heat-fused portion no longer have the fiber form before the fusion process. The fiber form means that the ratio (former / latter) of the fiber length to the diameter (calculated as a perfect circle) calculated from the cross-sectional area of ​​the fiber is 300 times or more. For example, in the "thermally fused" state, at least a part of the outer surface of the constituent fibers of the web melts, and the boundary with the outer surface of the other fibers becomes indistinguishable, and the fiber form before the fusion process is no longer retained. When the constituent fibers such as composite fibers are made of two or more resins, even if a specific resin does not melt and maintains the fiber form, the other resins melt, and the boundary between the outer surfaces of the constituent fibers becomes indistinguishable, and the fiber form before the fusion process is no longer retained. These can be observed by observing the cross section of the fused fiber portion with a scanning electron microscope (SEM).

[0019] "Embossed fusion" means that fibers are thermally fused together by external pressure and heat using an uneven member such as an emboss. More specifically, it means that the resin of at least one fiber at the bonding interface between the fibers is melted by pressure and heat (due to intermolecular friction or self-heating due to compression or due to external heating) and bonded to the other fiber. The term "embossed compression bonding" refers to the process in which fibers are compressed together by external pressure or heat using an uneven member such as an embossing. More specifically, it refers to the process in which a fiber adheres to another fiber without the resin being melted by heat or pressure.

[0020] The fibrous material constituting the web may be any ordinary fiber or heat-stretchable fiber. From the viewpoint of fluffiness and strength, the fibrous material may be continuous fiber or long fiber, but it is preferable to use short fiber because it is possible to change the surface tension of the fiber surface in each layer by using a fiber oil. Continuous fibers are essentially continuous fibers, except for broken portions of the fibers at the end faces of the product member and some broken fibers in the fuzzed portions, and are found in the spunbond method. The long fibers have an effective fiber length (80 mm or more) and are found in the meltblown process. Staple fibers are fibers that are 77 mm or less in length and are used in air-through nonwoven fabrics, spunlace nonwoven fabrics, and airlaid nonwoven fabrics.

[0021] Methods for supplying the unfused web include the spunbond method (before embossing, continuous fibers), the electrospinning method (continuous fibers), the spunmelt method (a method combining hot air stretching and cold air stretching, long fibers), the meltblown method (long fibers), the carding method (short fibers), and the airlaid method (short fibers). The spunbond method and the carding method are particularly preferred because they produce a bulky three-dimensional shaped nonwoven fabric. It is also possible to combine these supply methods.

[0022] The fiber material preferably contains thermoplastic fibers, and examples thereof include polyolefin fibers such as polyethylene (hereinafter also referred to as PE) fibers and polypropylene (hereinafter also referred to as PP) fibers, and fibers made solely of thermoplastic resins such as polyethylene terephthalate (hereinafter also referred to as PET) and polyamide. It is also possible to use composite fibers of a core-sheath type, side-by-side type, or other structure. In the present invention, it is preferable to use composite fibers. The composite fibers referred to here include core-sheath fibers in which a high melting point component is the core portion and a low melting point component is the sheath portion, and side-by-side fibers in which a high melting point component and a low melting point component are arranged in parallel. A preferred example of such a fiber is a fiber with a core-sheath structure in which the sheath component is polyethylene or low melting point polypropylene, and representative examples of the fiber with the core-sheath structure include fibers with PET (core) and PE (sheath), PP (core) and PE (sheath), PP (core) and low melting point PP (sheath), and the like. More specifically, the above-mentioned constituent fibers preferably contain 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 preferably polyethylene terephthalate and polyethylene, and the composite composition of the polypropylene composite fiber is preferably polyethylene terephthalate and low melting point polypropylene, more specifically, PET (core) and PE (sheath), and PET (core) and low melting point PP (sheath). The melting points of the resins used are measured under atmospheric pressure (N 2The melting point is measured in a gas atmosphere.

[0023] These fibers can be used alone or in combination of two or more to form the web. The web may also contain fibers other than thermoplastic fibers, such as natural fibers such as cotton and pulp, and regenerated fibers such as rayon and cupra. Therefore, it is preferable that the nonwoven fabric produced by the production method of the present invention contains the above-mentioned fibers.

[0024] In the method for producing a nonwoven fabric of the present invention, a shaping process is carried out on the support by two stages of meshing using two types of pushing members with different meshing directions. By changing the shaping direction in the first stage and the shaping direction in the second stage, convex portions with different shaping shapes can be formed in each direction. In addition, by carrying out separate shaping steps, the meshing amount (depth) can be controlled independently in each step. As a result, the processing can be suitably controlled so that a desired combination of heights can be formed for convex portions with different shaping shapes.

[0025] The method for producing a nonwoven fabric of the present invention includes two types of embodiments. One is a form (first embodiment) in which one type of unfused web is subjected to a two-stage shaping process to produce a nonwoven fabric. The other is a form (second embodiment) in which, when performing a two-stage shaping process on the above-mentioned unfused web (also referred to as a first unfused web), another unfused web (also referred to as a second unfused web) is laminated after the first stage shaping process, and the laminate is subjected to a second stage shaping process to produce a nonwoven fabric. In this way, the first unfused web is subjected to a two-stage shaping process, and the second unfused web is subjected to a one-stage shaping process. Each of these unfused webs may be a single layer or multiple layers.

[0026] Specifically, the method for producing the nonwoven fabric of the first embodiment includes the following steps (hereinafter also referred to as step (1-1), step (1-2), and step (1-3)). (1-1) A first shaping step in which an unfused web consisting of an aggregate containing fibers is shaped by engaging a support having a convex portion or a concave portion with a first pushing member having a pushing portion that can engage with the support. (1-2) A second shaping step in which the shaped unfused web is shaped by engaging the support with a second pushing member having a pushing portion capable of engaging with the support. (1-3) A heat treatment step in which fibers are fused with a heated fluid, or embossed or fused in the second shaping step or after the second shaping step.

[0027] The method for producing the nonwoven fabric according to the second embodiment includes the following steps (hereinafter also referred to as steps (2-1), (2-2), and (2-3)). (2-1) A first shaping step in which a first unfused web consisting of an aggregate containing fibers is shaped by engaging a support having a convex portion or a concave portion with a first pushing member having a pushing portion that can engage with the support. (2-2) A second shaping step in which a second unfused web is laminated on the shaped first unfused web on the support, and shaping is performed from the second unfused web side by engaging the support with a second pushing member having a pushing portion that can engage with the support. (2-3) A heat treatment step in which, during or after the second shaping step, fiber fusion is performed using a heated fluid, or emboss-pressure bonding or emboss-fusion is performed.

[0028] In both steps (1-1) and (1-2) of the first embodiment and steps (2-1) and (2-2) of the second embodiment, the meshing shaping treatment is carried out so as to satisfy the following requirements. In other words, the difference between the angle of the meshing direction of the pushing portion of the first pushing member relative to the machine flow direction (hereinafter also referred to as the MD direction) of the support and the angle of the meshing direction of the pushing portion of the second pushing member relative to the machine flow direction of the support is 60 degrees or more and 90 degrees or less.

[0029] The aforementioned meshing direction means the direction in which the pressed portion of the unfused web formed by meshing between the support and the pressing member extends in the planar direction of the unfused web. In other words, it is the direction in which the pressing portion of the pressing member extends. It is also the extension direction of the convex portion (ridge portion) grasped when the unfused web is viewed in plan after the unfused web is meshed and shaped in the thickness direction.

[0030] The angle of the meshing direction of the push-in portion of the first pushing member with respect to the MD direction of the support (first shaping process) and the angle of the meshing direction of the push-in portion of the second pushing member with respect to the MD direction of the support (second shaping process) are each determined based on the MD direction. In the first shaping process, the angle of the meshing direction of the push-in portion of the first pushing member is set to an inclination angle θ1 with respect to the MD direction. In the second shaping process, the angle of the meshing direction of the push-in portion of the second pushing member is set to an inclination angle θ2 with respect to the MD direction. The absolute value of the difference between the two angles |θ1-θ2| is set to be 60 degrees or more and 90 degrees or less.

[0031] By setting the difference in the meshing direction angle |θ1-θ2| within the above range, the two independent shaping directions are recognized as being substantially perpendicular to each other. From this viewpoint, the difference in the meshing direction angle |θ1-θ2| is preferably 70 degrees or more, and more preferably 80 degrees or more. As a result, the unfused web shaped in the thickness direction by the engagement of the support and the pushing member, and the nonwoven fabric obtained thereafter, can form streak-like convex portions (ridge portions) that are recognized to be substantially perpendicular in the planar direction. At this time, since the first shaping step and the second shaping step are performed separately, the amount of engagement can be controlled independently. As a result, the two-stage engagement shaping process can favorably control the height of the convex portions and the fiber structure of the convex portions so that the nonwoven fabric is bulky and thick, while increasing the strength of the support between the formed convex portions (vertical ridge portions and horizontal ridge portions) to provide an appropriate compression energy.

[0032] In addition, in the arrangement of the convex portions of the support, the direction in which the convex portions of the support are arranged in the MD direction is specified, and the angle between this direction and the MD direction is the angle θM of the convex portions of the support. Similarly, the direction in which the convex portions of the support are arranged in the CD direction is specified, and the angle between this direction and the MD direction is the angle θC of the convex portions of the support. The convex portions of the support may be discrete or continuous. For example, when the convex portions of the support are continuous in the MD direction in a ring shape, only the angle θM of the convex portions of the support is included. When the pressing member is a drum-shaped member formed by combining multiple rings in the direction of the rotation axis, and the ring portion forms a pressing portion extending in the direction of rotation (a ring-shaped roll), the angle θM of the support convex portion is preferably 0 degrees, since it is not necessary to synchronize and align the support and the pressing member to mesh with each other. The angle θC of the support convex portion is preferably 85 degrees or more and 89.5 degrees or less in order to prevent vibration during embossing or embossing. Furthermore, from the viewpoint of preventing direct contact between the convex portion of the support and the pushing portion of the pushing member, it is preferable that the angle θM of the convex portion of the support is the same as the inclination angle θ1 of the pushing portion of the first pushing member, and the angle θC of the convex portion of the support is the same as the inclination angle θ2 of the pushing portion of the second pushing member. As another pattern, it is preferable that the angle θM of the convex portion of the support is the same as the inclination angle θ2 of the pushing portion of the second pushing member, and the angle θC of the convex portion of the support is the same as the inclination angle θ1 of the pushing portion of the first pushing member.

[0033] The angle θM of the convex portion of the support is preferably greater than or equal to 0 degrees and less than or equal to 30 degrees, and the angle θC of the convex portion of the support is preferably greater than or equal to 60 degrees and less than or equal to 90 degrees, from the viewpoint of preventing direct contact between the convex portion of the support and the pushing portion of the pushing member.

[0034] The meshing direction angles θ1 and θ2 are both the smaller of the inclination angles with respect to the MD direction (0 degrees or more and 90 degrees or less), as shown in Figures 1(A) and 1(B). When the pushing portion of the pushing member is not continuous in the planar direction (such as in a dot shape), as shown in Figure 2, the direction in which the pitch of the pushing portion of the pushing member is short is specified, and the angle between this direction and the MD direction is the meshing direction angle. In Figures 1(A) and 1(B) and Figure 2, the symbol θ indicates either the meshing direction angle θ1 or θ2. Reference numeral 111 indicates a convex portion of the support, reference numeral 112A indicates a concave portion extending in the MD direction on the support, and reference numeral 112B indicates a concave portion extending in the CD direction on the support. Reference numeral 121 indicates a pushing portion of the first pushing member, and reference numeral 122 indicates a pushing portion of the second pushing member. In Figures 1(A) and (B) and Figure 2, the intervening unfused web is omitted in order to understand the extension direction of the pushing portion 121 of the first pushing member and the extension direction of the pushing portion 122 of the second pushing member in the planar direction of the support body.

[0035] Either of the two meshing direction angles shown in Fig. 1(A) and (B) may be the meshing direction angle θ1 in the first shaping step. Of the meshing direction angle configurations in Fig. 1(A) and (B), the one with angle θ1 is performed first as the first shaping step, and the one with angle θ2 is performed later as the second shaping step. Whichever shaping step in Fig. 1(A) or (B) is performed first, stripe-like convex portions that are recognized as being substantially perpendicular to each other can be formed within the above-mentioned meshing direction angle difference range |θ1-θ2|, and the meshing amount can be suitably controlled to increase the support strength between the convex portions (vertical ridge portions and horizontal ridge portions) that intersect with each other, making them less likely to collapse.

[0036] For example, an example of a form in which the angle θ2 (second shaping process) of the meshing direction of the pushing portion 122 of the second pushing member relative to the MD direction of the support is larger than the angle θ1 (first shaping process) of the meshing direction of the pushing portion 121 of the first pushing member relative to the MD direction of the support. In this case, it is preferable that the meshing direction angle θ1 of the push-in portion 121 of the first push-in member with respect to the MD direction of the support is 0 degrees or more and 30 degrees or less, and the meshing direction angle θ2 of the push-in portion 122 of the second push-in member with respect to the MD direction of the support is 60 degrees or more and 90 degrees or less. The meshing direction angle θ1 "0 degrees or more and 30 degrees or less" is almost an angle with respect to the MD direction of the support, and indicates a direction that is substantially recognized as the MD direction. Moreover, the meshing direction angle θ2 "60 degrees or more and 90 degrees or less" is almost an angle with respect to the CD direction of the support, and indicates a direction that is substantially recognized as the CD direction perpendicular to the MD direction of the support. For example, the inclination angle θ shown in FIG. 1(A) is set to the angle θ1 in the interlocking direction, and a first shaping process is carried out along the MD direction at this angle θ1 first, and the inclination angle θ shown in FIG. 1(B) is set to the angle θ2 in the interlocking direction, and a second shaping process is carried out along the CD direction at this angle θ2 secondly.

[0037] In addition, the angle θ2 (second shaping process) of the meshing direction of the pushing portion 122 of the second pushing member with respect to the MD direction of the support may be smaller than the angle θ1 (first shaping process) of the meshing direction of the pushing portion 121 of the first pushing member with respect to the MD direction of the support. In this case, it is preferable that the meshing direction of the push-in portion 121 of the first pushing member is 60 degrees or more and 90 degrees or less with respect to the MD direction of the support, and the meshing direction of the push-in portion 122 of the second pushing member is 0 degrees or more and 30 degrees or less with respect to the MD direction of the support. In this case, it can be said that the angle θ1 of the meshing direction indicates a direction that is substantially recognized as the CD direction, and the angle θ2 of the meshing direction indicates a direction that is substantially recognized as the MD direction. For example, the inclination angle θ shown in FIG. 1(B) is set to the angle θ1 in the interlocking direction, and a first shaping process is carried out along the CD direction at this angle θ1 first, and the inclination angle θ shown in FIG. 1(A) is set to the angle θ2 in the interlocking direction, and a second shaping process is carried out along the MD direction at this angle θ2 secondly.

[0038] When the meshing direction angle θ1 or θ2 is set to be "0 degrees or more and 30 degrees or less", the upper limit is more preferably 15 degrees or less, and even more preferably 5 degrees or less, from the viewpoint of approaching the angle θM of the convex portion 111 of the support. When the above-mentioned meshing direction angle θ1 or θ2 is set to "60 degrees or more and 90 degrees or less," the lower limit is more preferably 80 degrees or more, and even more preferably 87 degrees or more, from the viewpoint of approaching the angle θC of the convex portion 111 of the support body, and the upper limit is more preferably 89.5 degrees or less.

[0039] When the angle θ1=0 degrees or 90 degrees and the angle θ2=90 degrees or 0 degrees, the difference between the two angles is 90 degrees. In this case, it is preferable that the angle of one meshing direction is the MD direction and the angle of the other meshing direction is the CD direction. For example, as shown in FIG. 3(A), the pushing part 121 of the first pushing member may extend in the MD direction, and the meshing direction in the first shaping process may be the MD direction (θ1=0 degrees). In this case, as shown in FIG. 3(B), the pushing part 122 of the second pushing member may extend in the CD direction, and the meshing direction in the second shaping process may be the CD direction (θ2=90 degrees). Alternatively, the meshing direction in the first shaping process may be the CD direction (θ1=90 degrees), and the meshing direction in the second shaping process may be the MD direction (θ2=0 degrees).

[0040] In both steps (1-1) and (1-2) of the first embodiment and steps (2-1) and (2-2) of the second embodiment, the unfused web 100 is directly pressed in by mechanical pressure. This makes it possible to obtain a nonwoven fabric in which the fibers are strongly oriented and there are many components oriented perpendicular to the plane of the nonwoven fabric, compared to when the unfused web is pressed in by non-mechanical pressure such as wind. Furthermore, it is not necessary to apply a large pressing force to increase the height difference between the protrusions and recesses formed in the unfused web, and the unfused web can be shaped softly. Furthermore, it is possible to suppress fiber disorder and improve shaping properties. Since the meshing amount can be appropriately set and appropriately controlled independently in each shaping step, not only the height of the convex parts of the obtained nonwoven fabric can be appropriately controlled, but also the orientation of the fibers in the wall part of the convex parts along the thickness direction can be improved. In this way, the meshing amount can be appropriately controlled so that the convex parts of the nonwoven fabric are unlikely to collapse when compressed and an appropriate compression energy is applied to rebound appropriately in the thickness direction. In addition, by performing two-stage intermeshing shaping, the spacing between the fibers in the unfused web can be widened, and the area filled with fibers can be kept large to form a bulky structure. In this regard, the more the unfused web 100 is elongated by intermeshing shaping, the more the fiber orientation increases, while the fiber distance increases and the fiber density decreases, so that the bulk density of the fibers tends to decrease. By using an unfused web, the bond between the fibers is low, so that the unfused web can be elongated without breaking the fibers themselves even if it is highly elongated during intermeshing. In light of this, by controlling the amount of intermeshing in two stages, it is possible to simultaneously form a suitable fiber orientation, bulk density (bulk height), and protrusion height (thickness). As a result, a nonwoven fabric having a bulky and thick fiber structure, appropriate compression energy, and excellent feel can be suitably produced.

[0041] In both steps (1-1) and (1-2) of the first embodiment and steps (2-1) and (2-2) of the second embodiment, the meshing amount is preferably controlled as follows. That is, it is preferable that the ratio (former / latter) of the amount of engagement of push-in portion 121 of the first pushing member with the support to the amount of engagement of push-in portion 122 of the second pushing member with the support is 1.2 or more. Thereby, when the unfused web is pushed between convex portions 111, 111 of the support by push-in portion 121 of the first pushing member, the tension of the unfused web can also cause the unfused web to be inserted between the convex portions of the support in the extending direction of push-in portion 122 of the second pushing member other than the extending direction of push-in portion 121. It is possible to suitably control the ratio ({H2 / H1}×100) of the height H2 of the first intermediate convex portion 1A of the vertical ridge portion 1 to the height H1 of the top convex portion 15 and the ratio ({H3 / H1}×100) of the height H3 of the second intermediate convex portion 5A of the horizontal ridge portion 5 to the height H1 of the top convex portion 15. This allows the vertical ridge portion 1 and the horizontal ridge portion 5 to be clearly formed in the nonwoven fabric, which makes the vertical ridge portion 1 and the horizontal ridge portion 5 less likely to collapse, and provides a good texture, stabilizing the two-stage shaping process. In other words, the processing can be suitably controlled to achieve the desired combination of convex portion heights. This also makes it possible to independently control the height of the vertical ridge portion 1 and the height of the horizontal ridge portion 5. From this viewpoint, the ratio (former / latter) is more preferably equal to or greater than 1.4, and further preferably equal to or greater than 1.6. Furthermore, the ratio (former / latter) is preferably 3 times or less, more preferably 2.2 times or less, and even more preferably 1.8 times or less, from the viewpoint of enabling the first intermediate convex portion 1A and the second intermediate convex portion 5A described below to be set to appropriate heights and making the vertical ridge portion 1 and the horizontal ridge portion 5 less likely to collapse in both the vertical and horizontal directions.

[0042] In addition, in the first pushing member or the second pushing member, in which the meshing direction with respect to the machine flow direction of the support is 60 degrees or more and 90 degrees or less, it is preferable that the uniform gap in the MD direction formed by the convex portion 111 and the pushing portion 121 or 122 when meshed is 0.5 mm or more and 1.5 mm or less. The "uniform gap" refers to a gap in a state in which the length of the space between the convex portions in the MD direction before and after the pushing portion is uniform when the pushing portion is inserted into the space between the convex portions of the support. When the support and the pushing member are roll bodies, the uniform gap refers to the gap R1 in the MD direction before and after the pushing portion of the pushing member when the pushing portion of the pushing member is located in the center of the space formed between the convex portions of the support at a height position of 1 / 2 the meshing amount P1 on the line connecting the axial centers of the support and the pushing member (see FIG. 4). Also, when the pushing portion has an uneven thickness, such as when the cross-sectional shape in the longitudinal direction has a large diameter, it refers to the average gap at the meshing portion. As shown in Fig. 4, the meshing amount P1 means the difference in height between the tip of the convex portion 111 of the support and the tip of the pushing portion 121 or 122 of the pushing member. In the case of a roll shape, the meshing amount P1 is calculated as the sum of the outer diameter radius at the tip of the convex portion 111 of the support and the outer diameter radius at the tip of the pushing portion 121 or 122 of the pushing member, minus the distance between the axial centers of the rolls. The uniform gap is preferably 0.5 mm or more, and more preferably 0.7 mm or more, from the viewpoint of preventing the unfused web from being excessively compressed and becoming bulky, and of facilitating peeling of the unfused web from the pushing member at the exit side of the support and the pushing member. From the viewpoint of appropriately compressing the fiber and suppressing fluff, the uniform gap is preferably 1.5 mm or less, and more preferably 1.2 mm or less.

[0043] Furthermore, in the first pushing member or the second pushing member, in which the meshing direction of the support is 60 degrees or more and 90 degrees or less with respect to the machine direction, it is preferable that the ratio (R1 / P1) of the uniform gap R1 to the meshing amount P1 is 0.1 or more and 1 or less (see FIG. 4). By making it above the lower limit, interference between the support and the pushing member due to thermal expansion is less likely to occur, and by making it below the upper limit, it is easier to orient the fibers of the unfused web in the thickness direction due to the meshing, and the thickness due to shaping can be increased. From the above viewpoints, the ratio (R1 / P1) is more preferably equal to or greater than 0.15, and further preferably equal to or greater than 0.20. From the same viewpoint, the ratio (R1 / P1) is more preferably equal to or less than 0.8, and further preferably equal to or less than 0.5.

[0044] Next, an example of step (1-1) and step (1-2) in the method for producing the nonwoven fabric of the first embodiment will be shown with reference to FIGS. 5(A) to (D). 5(A) to (D) show examples of an embodiment in which the meshing direction of the first pushing member in the first shaping step (1-1) is the MD direction, and the meshing direction of the second pushing member in the second shaping step (1-2) is the CD direction. Fig. 5(A) shows an example of the meshing state in the first shaping step. In this step, the unfused web 100 is supported by the convex portions 111 of the support 110, and the pushing portion 121 of the first pushing member 120A pushes the first unfused web 100 in the concave portions 112A between the convex portions 111, 111. When this meshing state is viewed in plan from the side of the first pushing member 120A as shown in Fig. 5(B), the meshing direction of the pushing portion 121 is the MD direction. In this example, the support 110 has the convex portions 111 arranged at equal intervals in the MD and CD directions, and the concave portions 112A extending in the MD direction and the concave portions 112B extending in the CD direction are arranged in a lattice pattern while intersecting each other. In the first shaping step, the pushing portion 121 of the first pushing member 120A is engaged with the recessed portion 112A extending in the MD direction of the support 110. The engaging direction is the MD direction. This causes the pushed portion of the unfused web 100 to be stretched and shaped into a convex shape along the MD direction toward the support. The portion shaped into a convex shape along the MD direction becomes the vertical rib portion 1 in the nonwoven fabric 10 described below (see, for example, FIG. 6). The first pushing member 120A is peeled off from the unfused web 100, and thereafter the unfused web 100 is held on the support 110. Methods for holding the web include sucking from the back side of the support 110 where there is no convex portion 111, increasing the surface roughness of the side surface of the convex portion 111 of the support 110, and decreasing the surface roughness of the side surface of the pushing portion 121 of the pushing member 120A. FIG. 5(C) shows an example of the meshing state in the second shaping step. In this step, the pushing portion 122 of the second pushing member 120B is pushed into the unfused web 100 held by the support 110 after the first shaping step. Specifically, the pushing portion 122 of the second pushing member 120B is pushed into the unfused web 100 in the recessed portion 112B between the protruding portions 111, 111 of the support 110. When this meshing state is viewed in plan from the side of the second pushing member 120B as shown in FIG. 5(D), the meshing direction of the pushing portion 122 is the CD direction. That is, in the second shaping step, the pushing portion 122 of the second pushing member 120B meshes with the recessed portion 112B extending in the CD direction of the support 110. The meshing direction is the CD direction. The unfused web 100 is pushed in along the CD direction perpendicular to the MD direction so as to partially overlap the portion formed into a convex shape along the MD direction. As a result, the pushed-in portion of the unfused web 100 is stretched and formed into a convex shape along the CD direction toward the support. The portion formed into a convex shape along the CD direction becomes the horizontal ridge portion 5 in the nonwoven fabric 10 described below (see, for example, FIG. 6). The fiber layer held by the convex portion 111 of the support 110 becomes the bottom portion 2 recessed into the concave shape in the nonwoven fabric 10 described below (see, for example, FIG. 6). In the first unfused web 100, the portion that is inserted between the convex portions 111, 111 of the support 110 becomes the convex portion (uppermost convex portion 15) of the nonwoven fabric.

[0045] The unfused web 100 thus subjected to the two-stage shaping process is turned into a nonwoven fabric 10 (see, for example, FIG. 6) through the heat treatment process of the above-mentioned process (1-3). In the above-mentioned process (1-3), in the second shaping process or after the second shaping process, fiber fusion is performed with a heated fluid, or embossed pressure bonding or embossed fusion is performed. As a result, interlayer fiber intersection heat fusion parts P, or embossed pressure bonding parts or embossed fusion parts are formed, and the nonwoven fabric of the present invention is manufactured. The heat treatment process of the process (1-3) may be performed multiple times, not just once. For example, fiber fusion with a heated fluid may be performed multiple times, or the fiber heat fusion with the heated fluid and embossed pressure bonding or embossed fusion may be combined. In the case of the above-mentioned fiber thermal fusion using a heated fluid, it is preferable that the recess 112 of the support 110 has an opening 113 for passing the heated fluid in the step (1-3).

[0046] As described above, the obtained nonwoven fabric 10 has vertical ridges 1 that are convex along the MD direction and horizontal ridges 5 that are convex along the CD direction. As an example, the vertical ridges 1 are formed mainly in the first shaping step by the first pushing member 120A (for example, the row of vertical ridges 1 in FIG. 6), and the horizontal ridges 5 are formed mainly in the second shaping step by the second pushing member 120B (for example, the row of horizontal ridges 5 in FIG. 6). The uppermost convex portion 15 is the intersection of the first shaping step and the second shaping step. The uppermost convex portion 15 is formed mainly under the influence of the larger pushing amount depending on the respective pushing amounts. As an example, the bottom portion 2 in FIG. 6 is formed at the position of the convex portion 111 of the support 110. In addition, after the second shaping step, when the shaped unfused web 100 is embossed or fused on the support 110 by pressing the convex portion 111 of the support 110 with another roll or horn, the bottom portion 2 becomes the embossed or fused portion. The vertical ridge portion 1 and the horizontal ridge portion 5 protrude on the same surface side of the front and back surfaces of the nonwoven fabric. The protruding surface side is the front surface side 10T, and the opposite surface side is the back surface side 10B. In a plan view from the front surface side 10T of the nonwoven fabric 10, the vertical ridge portions 1 and the horizontal ridge portions 5 are arranged in a plurality of positions perpendicular to each other. In the area surrounded by the vertical ridge portions 1 and the horizontal ridge portions 5, the bottom portion 2 is recessed in a concave shape on the back surface side 10B.

[0047] The portion 1A of the vertical ridge portion 1 that was not reached by the second shaping step described above (e.g., meshed in the first shaping step but not meshed in the second shaping step), and the portion 5A of the horizontal ridge portion 5 that was not reached by the first shaping step described above (e.g., not meshed in the first shaping step but meshed in the second shaping step) are each subjected to only one stage of meshing shaping. In addition, these portions 1A and 5A are sandwiched between the convex portions 111, 111 of the support 110 in the first shaping step and the second shaping step described above, and after shaping, the fibers return from the pressed state, and in that state, the nonwoven fabric is formed by the heat treatment step. On the other hand, the portion 15 where the vertical ridge portion 1 and the horizontal ridge portion 5 intersect is subjected to the shaping process in both the first shaping step and the second shaping step by a pressing member from the surface side that becomes the back side 10B, and is pressed most strongly to form a nonwoven fabric. Therefore, in the nonwoven fabric 10, as shown in Figs. 7 to 10, the portion 15 where the vertical rib portion 1 and the horizontal rib portion 5 intersect becomes the highest in the thickness direction Z, which is the uppermost convex portion 15. In contrast to the uppermost convex portion 15, the portion 1A of the vertical rib portion 1 and the portion 5A of the horizontal rib portion 5 described above undergo a first shaping process to become relatively lower in height in the thickness direction Z, becoming the first middle convex portion 1A and the second middle convex portion 5A. In other words, "height H1 of the uppermost convex portion 15 > height H2 of the first middle convex portion 1A, height H3 of the second middle convex portion 5A". The height H2 of the first intermediate convex portion 1A and the height H3 of the second intermediate convex portion 5A can be appropriately set by the meshing amount of the push-in member in each of the first shaping process and the second shaping process. That is, the height H2 of the first intermediate convex portion 1A is formed by the meshing amount of the first push-in member 120A, and the height H3 of the second intermediate convex portion 5A is formed by the meshing amount of the second push-in member 120B. That is, the heights H2 and H3 can be set and imparted separately in one nonwoven fabric by separately controlling the meshing amount. For example, when a support 110 having a convex portion 111 arranged as shown in FIG. 5 is used and the meshing amount of the push-in member is larger in the first shaping process than in the second shaping process, "the height H2 of the first intermediate convex portion 1A>the height H3 of the second intermediate convex portion 5A".

[0048] In the nonwoven fabric 10 obtained as described above, the top convex portion 15, the first intermediate convex portion 1A, and the second intermediate convex portion 5A are preferably arranged in descending order of height in the thickness direction. The top convex portion 15 and the first intermediate convex portion 1A preferably form a vertical ridge portion 1 continuing in the MD direction, and the top convex portion 15 and the second intermediate convex portion 5A preferably form a horizontal ridge portion 5 continuing in the CD direction. The portion surrounded by the vertical ridge portion 1 and the horizontal ridge portion 5 becomes the bottom portion 2 that is recessed in a concave shape. In the above-mentioned uneven shape of the nonwoven fabric 10, the height of the top convex portion 15 is referred to as the ridge height. When the second intermediate convex portion 5A is considered to have the lowest height in the thickness direction Z among the above-mentioned three types of convex portions, it is also referred to as a saddle portion connecting the vertical ridge portions 1, 1 to each other. In the following, the nonwoven fabric 10 will be described as having the relationship "height H2 of the first intermediate convex portion 1A > height H3 of the second intermediate convex portion 5A." However, the nonwoven fabric 10 is not limited to having this relationship, and may have a different height relationship from the above as long as it does not contradict the following description.

[0049] The heights H1, H2, and H3 of the uppermost convex portion 15, the first intermediate convex portion 1A, and the second intermediate convex portion 5A are determined based on the surface of the bottom portion 2 as a correlation between the resistance to collapse and the uneven feel when viewed from the surface side. On the front and back sides of the nonwoven fabric, the surface side from which each convex portion protrudes is referred to as the front side, and the opposite surface side with the bottom portion 2 is referred to as the back side. That is, the height of the uppermost convex portion 15 is the height in the thickness direction of the nonwoven fabric from the surface of the bottom portion 2 to the surface of the uppermost convex portion 15. The height of the first intermediate convex portion 1A is the height in the thickness direction of the nonwoven fabric from the surface of the bottom portion 2 to the surface of the first intermediate convex portion 1A. The height of the second intermediate convex portion 5A is the height in the thickness direction of the nonwoven fabric from the surface of the bottom portion 2 to the surface of the second intermediate convex portion 5A. Specifically, the heights H1, H2, and H3 of the uppermost convex portion 15, the first intermediate convex portion 1A, and the second intermediate convex portion 5A (hereinafter, these are also collectively referred to simply as convex portions) can be measured by the following method.

[0050] (Method of measuring the heights H1, H2, and H3 of the uppermost convex portion 15, the first intermediate convex portion 1A, and the second intermediate convex portion 5A) (1) Cut the nonwoven fabric to be measured with scissors or similar to obtain a sample. If the nonwoven fabric is bonded to other materials (for example, if it is incorporated as a component of an absorbent article), sample it while it is still bonded to the other materials. Place the nonwoven fabric in an unloaded state with the convex part facing up, and store it at a temperature of 23±2°C and a humidity of 65±5% RH for 48 to 72 hours. (2) The sample is prepared into a rectangular shape with a length of 5 times the pitch of the top convex portion 15 × 5 times the pitch of the top convex portion 15. At this time, in a plan view of the nonwoven fabric, one side is cut in the thickness direction with sharp scissors or the like, with the top convex portion 15 at the center on a line including the center of the top convex portion 15 to be observed (the top of the top convex portion 15) and the center of the bottom portion 2 adjacent to the top convex portion 15 (cut line 1, cross section IV in Figure 6) (for example, Figure 10). The direction of cut line 1 can be the MD direction, the CD direction, or a diagonal direction. The cross section of cut line 1 is colored with a marker or the like. Similarly, one side is cut in the thickness direction with sharp scissors or the like, with the first intermediate convex portion 1A at the center, on a line including the center of the first intermediate convex portion 1A (the center of the top of the first intermediate convex portion 1A) to be observed and the center of the bottom portion 2 adjacent to the first intermediate convex portion 1A (cut line 2, cross section II in FIG. 6) (for example, FIG. 8). Also, one side is cut in the thickness direction with sharp scissors or the like, with the second intermediate convex portion 5A at the center, on a line including the center of the second intermediate convex portion 5A (the center of the top of the second intermediate convex portion 5A) to be observed and the center of the bottom portion 2 adjacent to the second intermediate convex portion 5A (cut line 3, cross section III in FIG. 6) (for example, FIG. 9). (3) Observe the cross-sections of the unevenness from the cross-section samples at cut lines 1, 2, and 3. Place the cross-section samples on a flat plate with the convex side facing up, and apply a load of 0.5 gf / cm 2 At this time, the position of the sample cross section and the edge of each plate are aligned. (4) Using a microscope (e.g., VHX-6000 (product name) manufactured by Keyence Corporation), the cross section of the sample is observed from the side. Three convex portions and four bottom portions 2 located in the center of the sample aligned along each cut line are observed at a magnification of 10 to 300 times. (5) As shown in Figures 8, 9, and 10, the height of each convex part is determined by observing the cross section of each cut line. (6) Each value is the average value of five points using different sample sides. (7) In the case where a plurality of fiber layers are laminated, such as the nonwoven fabric 20 obtained by the manufacturing method of the nonwoven fabric of the second embodiment described later, the boundaries of each fiber layer are drawn using the observation image and the colored portion as a guide. When it is difficult to distinguish each fiber layer, the boundaries can be grasped by differences in layer structure, such as differences in fiber diameter, differences in fiber orientation, differences in fiber cross-sectional shape, gaps between layers, differences in fiber density, differences in the number of fibers per unit area, differences in basis weight, etc. For example, in the case of using the number of fibers, the boundary where the number of fibers of each fiber layer at the interface between fiber layers is 1 / 2 of the center of the fiber layer is drawn as an outline. As the resolution at this time, a square grid is drawn with one pitch being 1 / 50 of the total thickness of the nonwoven fabric, and the number of fibers within the square is counted. The outline of the squares where the number of fibers is 1 / 2 or more and less than 1 / 2 of the average number of fibers in the center of each fiber layer is smoothed and connected to form the boundary. If there is a place in the fiber layer where the number of fibers is less than 1 / 2, it is excluded from the boundary line. In the nonwoven fabric 20 described below, the height of each projection is determined by observing the cross section of each cut line for each of the first fiber layer 11 and the second fiber layer 22 as shown in Figs.

[0051] In the nonwoven fabric 10, it is preferable that in the vertical rib portion 1, the uppermost convex portion 15 and the first intermediate convex portion 1A are connected in a mountain range shape with a gradual difference in height, and that in the horizontal rib portion 5, the uppermost convex portion 15 and the second intermediate convex portion 5A are connected with a greater difference in height than the vertical rib portion 1. This height difference can be suitably set by controlling the amount of meshing independently in the first shaping step and the second shaping step of the nonwoven fabric manufacturing method of the present invention so as to appropriately increase the collapse resistance of the vertical rib portion 1 and the horizontal rib portion 5. From the same viewpoint, the height difference between the first intermediate convex portion 1A and the second intermediate convex portion 5A can also be suitably controlled in the nonwoven fabric manufacturing method of the first embodiment. In this way, the nonwoven fabric manufacturing method of the first embodiment can suitably manufacture a nonwoven fabric 10 that has a bulky and thick structure, yet has a suitable compression energy and is excellent in texture.

[0052] In the nonwoven fabric 10, a preferred embodiment of the relationship between the height H2 of the first intermediate convex portion 1 and the height H3 of the second intermediate convex portion 5A is shown below with reference to Fig. 9 (a cross section taken along line III-III in Fig. 6 when obtained by the manufacturing method for the nonwoven fabric of the first embodiment). Note that the embodiment below can also be applied to the example of Fig. 14 (a cross section taken along line III-III in Fig. 6 when obtained by the manufacturing method for the nonwoven fabric of the second embodiment) described later. The ratio ({H2 / H1}×100) of the height H2 of the first intermediate convex portion 1A located in the vertical ridge portion 1 to the height H1 of the uppermost convex portion 15 is preferably 40% or more, more preferably 45% or more, even more preferably 50% or more, and even more preferably 55% or more, from the viewpoint of increasing the support strength between the vertical ridge portion 1 and the horizontal ridge portion 5 and making the horizontal ridge portion 5 less likely to collapse in the vertical direction. From the viewpoint of further enhancing the soft and good texture and of making the protrusions more easily recognizable as distinct, independent protrusions in appearance, the above ratio is more preferably 75% or less, more preferably 70% or less, and even more preferably 65% ​​or less.

[0053] In addition, a preferred embodiment of the relationship between height H1 of the uppermost convex portion 15 and height H3 of the second intermediate convex portion 5A in the nonwoven fabric 10 is shown below with reference to Fig. 8 (a cross section taken along line II-II in Fig. 6 in the case of a fabric obtained by the manufacturing method for the nonwoven fabric of the first embodiment). The embodiment below can also be applied to the example of Fig. 13 (a cross section taken along line II-II in Fig. 6 in the case of a fabric obtained by the manufacturing method for the nonwoven fabric of the second embodiment) described later. The ratio ({H3 / H1}×100) of the height H3 of the second intermediate convex portion 5A located in the horizontal ridge portion 5 to the height H1 of the uppermost convex portion 15 is preferably 40% or more, and more preferably 45% or more, from the viewpoint of increasing the support strength between the horizontal ridge portion 5 and the vertical ridge portion 1 and making it less likely that the vertical ridge portion 1 will collapse laterally. From the viewpoint of further enhancing the soft and good texture and making the protrusions more easily recognizable as clearly independent protrusions in appearance, the above ratio is more preferably 75% or less, more preferably 65% ​​or less, even more preferably 60% or less, and even more preferably less than 55%.

[0054] In nonwoven fabric 10, from the viewpoint of further increasing the collapse resistance of vertical rib portions 1 and horizontal rib portions 5 along with a good texture, within the above-mentioned ranges ({H2 / H1}×100, {H3 / H1}×100), it is preferable that the ratio {|H2-H3| / H1}×100 of the absolute value of the difference between the height H2 of the first intermediate convex portion 1A and the height H3 of the second intermediate convex portion 5A to the height H1 of the uppermost convex portion 15 is greater than 0% and not greater than 25%. In comparison with the horizontal ridge portion 5, from the viewpoint of forming continuous ridges with less undulation from the uppermost convex portion 15 in the vertical ridge portion 1, the above ratio is more preferably 3% or more, and further preferably 5% or more. Moreover, from the viewpoint of making the uppermost convex portion 15 less likely to collapse in both the MD and CD directions, the above ratio is more preferably 20% or less, and further preferably 15% or less. These can be controlled by the amount of engagement by the first pushing member 120A and the amount of engagement by the second pushing member 120B in the MD and CD directions.

[0055] In the example shown in Fig. 5(A) to (D), the meshing direction in the first shaping process is the MD direction, and the meshing direction in the second shaping process is the CD direction, but this is not limited thereto. The meshing direction in the first shaping process may be the CD direction, and the meshing direction in the second shaping process may be the MD direction. In this case, in the nonwoven fabric 10 shown in Figs. 6 to 10, the arrangement of the first intermediate convex portion 1A and the second intermediate convex portion 5A is switched, and the vertical ridge portion 1 (top convex portion 15 + first intermediate convex portion 1A) extends in the CD direction, and the horizontal ridge portion 5 (top convex portion 15 + second intermediate convex portion 5A) extends in the MD direction. This point is also applicable to the nonwoven fabric 20 shown in Figs. 12 to 15.

[0056] As described above, the three types of convex parts of the nonwoven fabric 10 can only be obtained by performing the above-mentioned two-stage meshing shaping process separately and independently. For example, in a one-stage shaping process in which the ring-shaped roll of FIG. 8 meshes with the support roll of FIG. 2 described in the above-mentioned Patent Document 2, the vertical ridges can be controlled by the meshing amount of the ring-shaped roll, but the horizontal ridges are left to their own devices. When the lattice roll of FIG. 3 described in the same document is used as a pressing member to mesh with the support roll in the thickness direction simultaneously along the MD and CD directions, the meshing amount in the CD direction is limited from the viewpoint of avoiding interference with the support roll rotating in the MD direction. In this case, due to the structure of the lattice roll, it is difficult to control the meshing amount in the CD direction and the meshing amount in the MD direction separately, and the meshing amount in the MD direction must be matched to the meshing amount in the CD direction. In addition, the support roll is more likely to expand in the CD direction than in the MD direction due to heat during operation. In response to this difference in thermal expansion, it becomes difficult to correct the meshing amount in each direction separately in the CD and MD to prevent interference between the meshing lattice rolls. In contrast, in the method for producing a nonwoven fabric of the present invention, the first shaping step and the second shaping step are carried out separately in two stages, so that the meshing amount (the amount of pressing in the thickness direction) can be controlled independently in each step, thereby making it possible to suitably form a unique nonwoven fabric having protrusions of three different heights, as described above. As the two-stage shaping process, for example, in Fig. 5 (A) to (D), the first shaping process may use a ring-shaped roll to perform shaping in the thickness direction along the MD direction, and the second shaping process may use a gear roll to perform shaping in the thickness direction along the CD direction. Alternatively, the opposite to Fig. 5 (A) to (D), the first shaping process may use a gear roll to perform shaping in the thickness direction along the CD direction, and the second shaping process may use a ring-shaped roll to perform shaping in the thickness direction along the MD direction. It is preferable to first press the unfused web into the support by the ring-shaped roll, from the viewpoint that the unfused web is less likely to float from the support after the first shaping process and is more likely to be stably held.

[0057] In the shaping step in which the rollers are engaged in the thickness direction along the CD direction, it is preferable to use a pushing member that is more flexible than the gear roll described above in order to avoid interference with the support roll and increase the amount of engagement. An example of this pushing member is a roll body with a flexible blade built into the support (not shown). The blade serves as the pushing portion of the pushing member. The blade is a plate made of metal or resin in a plate shape. For example, the blade may be a thin blade having a thickness of 0.5 mm or more and 1 mm or less. Even if such a blade is used for interlocking shaping in the CD direction, it is difficult to break because it bends even if it interferes with the support roll. Therefore, in interlocking shaping in the CD direction using a blade, it is possible to more suitably control the interlocking to be deeper, separately and independently from the above-mentioned shaping in the MD direction. From the viewpoint of suitable control of the above-mentioned meshing shaping, it is preferable that the pushing member is not one in which the blade is integrally formed with the support part, but one in which the blade is incorporated into the insertion groove part of the support part. This further increases the flexibility of the blade. By increasing the degree of freedom of the blade, even if the meshing amount increases, the convex part of the support and the pushing part of the pushing member can mesh without direct interference (high pressure contact). Furthermore, it is preferable that there is an average gap of 0.01 mm or more and 0.1 mm between the support part and the blade that constitute the pushing member. By having a moderate flexibility range, a larger meshing amount can be achieved. The gap refers to the difference between the average thickness of the blade at the embedding part and the average width of the insertion groove part of the support part.

[0058] 5(A) to 5(D) and 6 to 10 show nonwoven fabric 10 formed using one type of unfused web by the nonwoven fabric manufacturing method of the first embodiment. In this nonwoven fabric 10, Fig. 6 shows one example of the arrangement of uppermost convex portion 15, first intermediate convex portion 1A and second intermediate convex portion 5A, but is not limited to this. For example, it may be the arrangement shown in Fig. 11. The arrangement shown in Fig. 11 can be formed by carrying out the first shaping step of step (1-1) and the second shaping step of step (1-2) in the method for producing the nonwoven fabric of the first embodiment as follows. Specifically, the support is formed using a staggered arrangement of convex portions (the convex portions are arranged at positions corresponding to the bottom 2 in FIG. 11, not shown). In the first shaping step, a first pushing member (e.g., a ring-shaped roll) is engaged between the convex portions of the support (regions that form the rows of vertical ridge portions 1 in FIG. 11) to perform shaping in the thickness direction along the MD direction. In the second shaping step, a second pushing member (e.g., a gear roll) is used between the convex portions of the support (regions that form the rows of horizontal ridge portions 5 in FIG. 11) to perform shaping in the thickness direction along the CD direction. The top convex portion 15 is located at the intersection of the pushing regions of the first pushing member and the second pushing member, and is mainly formed by the one with the larger amount of engagement. The first shaping step and the second shaping step may be performed in reverse order. However, it is preferable to push the unfused web into the support first using the first pushing member (e.g., a ring-shaped roll) from the viewpoint that the unfused web is less likely to float from the support after the first shaping step and is more likely to be stably held. The nonwoven fabric 10 thus obtained has one type of intermediate convex portion A. Therefore, the vertical ridge portion 1 is formed by the uppermost convex portion 15 and the intermediate convex portion A, and the horizontal ridge portion 5 is formed by the uppermost convex portion 15 and the intermediate convex portion A.

[0059] Next, an example of step (2-1) and step (2-2) in the method for producing the nonwoven fabric of the second embodiment will be described. In the method for producing a nonwoven fabric of the second embodiment, the unfused web 100 used in the first embodiment is used as a first unfused web 100. In step (2-1), a first shaping step is performed on the first unfused web 100. Thereafter, in step (2-2), a second unfused web 200 is layered on the shaped first unfused web 100, and a second shaping step is performed from the second unfused web 200 side (see Figs. 17 and 18). This differs from the first embodiment in that in step (2-2), the second unfused web 200 is layered, and the second shaping step is performed from the second unfused web 200 side. In the second shaping step, the second unfused web 200, together with the first unfused web 100, is engaged and shaped by the pushing portion 122 of the second pushing member 120B at the recessed portion 112B extending in the CD direction of the support 110. As a result, the portion of the second unfused web 200 pushed in a direction perpendicular to the MD direction is elongated, and the second unfused web 200, together with the first unfused web 100, is shaped into a convex shape along the CD direction toward the support. For example, when the convex portions 111 of the support 110 are arranged as shown in Fig. 5, the above-mentioned convex shaped portions become the uppermost convex portion 215 and the second middle convex portion 25A of the second fiber layer 22 described later, which correspond to the uppermost convex portion 15 and the second middle convex portion 5A of the first fiber layer 11 described later (similar to the nonwoven fabric 10 described above) (see Figs. 12 to 15). The first middle convex portion 21A of the second fiber layer 22 (opposing the first middle convex portion 1A of the first fiber layer 11 described later) is formed as follows. That is, the portion of the second unfused web 200 that becomes the first middle convex portion 21A is not directly pressed into the support 110 by the second pressing member 120B, but is influenced by the second pressing member 120B that is pressed into the support 110 along the rows of adjacent horizontal ribs 5. As a result, the fibers of the second unfused web 200 are pulled in the MD direction, and the portion that will become the first intermediate convex portion 21A enters between the convex portions 11, 111 of the support 110, forming an intermediate height (see Figs. 12 to 15). The fiber layer held by the convex portions 111 of the support 110 becomes a concavely recessed bottom portion 2B in the second fiber layer 22 described below. After being shaped in this way, the nonwoven fabric is subjected to the heat treatment step (2-3) described above to become the nonwoven fabric 20. The step (2-3) is carried out in the same manner as the step (1-3) in the first embodiment. A nonwoven fabric 20 obtained by the method for producing a nonwoven fabric according to the second embodiment will be described below as being formed using a support 110 having convex portions 111 arranged as shown in Fig. 5. However, the nonwoven fabric 20 is not limited to this, and as described above, an uppermost convex portion and an intermediate convex portion similar to those shown in Fig. 11 may be formed.

[0060] The nonwoven fabric 20 has a first fiber layer 11 obtained from the first unfused web 100 and a second fiber layer 22 obtained from the second unfused web 200. In the nonwoven fabric 20, the first fiber layer 11 and the second fiber layer 22 overlap each other to form the longitudinal rib portion 1 and the transverse rib portion 5 shown in the nonwoven fabric 10 described above. That is, in the longitudinal rib portion 1, the uppermost convex portion 215 and the first intermediate convex portion 21A of the second fiber layer 22 are laminated onto the uppermost convex portion 15 and the first intermediate convex portion 1A of the first fiber layer 11. In the transverse rib portion 5, the uppermost convex portion 215 and the second intermediate convex portion 25A of the second fiber layer 22 are laminated onto the uppermost convex portion 15 and the second intermediate convex portion 5A of the first fiber layer 11.

[0061] In the second fiber layer 22, it is preferred that the bottom portion 2B and the second intermediate convex portion 25A are in contact with and integrated with the bottom portion 2 and the second intermediate convex portion 5A of the first fiber layer 11. On the other hand, it is preferred that the top convex portion 215 and the first intermediate convex portion 21A in the second fiber layer 22 include portions that protrude toward the top convex portion 15 and the first intermediate convex portion 1A of the first fiber layer 11 but do not contact each other, and that a void portion 8 is provided between both layers. This is because the second unfused web 200, unlike the first unfused web 100, is not subjected to the first shaping step, but is subjected to only the second shaping step. It is preferable that the voids 8 are continuous along the extending direction of the vertical rib portions 1. This can be formed, for example, as follows. That is, the voids 8 located on the uppermost convex portion 215 are formed by increasing the degree of meshing between the first pushing member 120A and the support 110 compared to the second pushing member 120B, so that the second unfused web 200 is not pushed in so far that it comes into contact with the first unfused web 100. The voids 8 located on the first intermediate convex portion 21A are formed by not pushing the second unfused web 200 in by the second pushing member 120B. In this way, according to the method for producing a nonwoven fabric of the second embodiment, a more complex uneven structure in the thickness direction can be suitably formed, and thus the nonwoven fabric 20 can be suitably produced as one having a bulky and thick structure, appropriate compression energy, and excellent texture.

[0062] The heights H21, H22, and H23 in the thickness direction of the top convex portion 215, the first intermediate convex portion 21A, and the second intermediate convex portion 25A in the second fiber layer 22 correspond to the heights H1, H2, and H3 in the thickness direction of the top convex portion 15, the first intermediate convex portion 1A, and the second intermediate convex portion 5A in the first fiber layer 11. The heights H21, H22, and H23 in the thickness direction of the top convex portion 215, the first intermediate convex portion 21A, and the second intermediate convex portion 25A in the second fiber layer 22 can be increased in the order of H23, H22, and H21 by increasing the degree of meshing between the first pushing member 120A and the support 110 more than the second pushing member 120B. Such a height relationship is preferable because it makes the top convex portion 15 less likely to collapse and provides an appropriate void ratio, which will be described later. The heights H21, H22, and H23 in the thickness direction of the second fiber layer 22 are also determined with respect to the surface of the bottom portion 2, as described above.

[0063] With regard to the second fiber layer 22, the ratio ({H22 / H21}×100) of the height H22 of the first intermediate convex portion 21A shown in FIG. 13 and FIG. 15 to the height H21 of the uppermost convex portion 215 is preferably 40% or more, more preferably 45% or more, and even more preferably 50% or more, from the viewpoint of increasing the support strength of the vertical rib portions 1 and making the vertical rib portions 1 less likely to collapse in the MD direction when the nonwoven fabric 20 is compressed and crushed. From the viewpoint of further enhancing the soft and good texture and making the protrusions more easily recognizable as clearly independent protrusions in appearance, the above ratio is more preferably 75% or less, more preferably 70% or less, even more preferably 65% ​​or less, and even more preferably 60% or less.

[0064] In addition, the ratio ({H23 / H21}×100) of the height H23 of the second intermediate convex portion 25A shown in Figures 14 and 15 to the height H21 of the uppermost convex portion 215 is preferably 45% or more, from the viewpoint of further increasing the support strength of the horizontal ridge portions 5 and making it less likely for the vertical ridge portions 1 to collapse in the CD direction. From the viewpoint of further enhancing the soft and good texture, the above proportion is preferably 55% or less, and more preferably 50% or less.

[0065] In nonwoven fabric 20, from the viewpoint of further increasing the collapse resistance of vertical rib portion 1 and horizontal rib portion 5 along with a good texture, within the above-mentioned ranges ({H22 / H1}×100, {H23 / H1}×100), it is preferable that the ratio of the absolute value of the difference between the height H22 of the first intermediate convex portion 21A and the height H23 of the second intermediate convex portion 25A to the height H21 of convex portion 215, {|H22-H23| / H21}×100, is greater than 0% and not greater than 25%. The above ratio is more preferably 3% or more, and even more preferably 5% or more, from the viewpoint of forming continuous ridges with less undulations from the uppermost convex portion 215 of the second fiber layer 22 in the vertical ridge portion 1 compared to the horizontal ridge portion 5. From the viewpoint of making it difficult for the uppermost convex portions 215 of the second fiber layer to collapse in both the MD and CD directions, the above ratio is more preferably 20% or less, and even more preferably 15% or less.

[0066] In the nonwoven fabric 20, the overlap in the thickness direction between the uppermost convex portion 15 of the first fiber layer 11 and the uppermost convex portion 215 of the second fiber layer 22 preferably includes at least the following configuration. That is, in the overlap, the interface between the wall portion 11B of the uppermost convex portion 15 of the first fiber layer 11 and the wall portion 22B of the uppermost convex portion 215 of the second fiber layer 22 preferably includes an interlayer fiber intersection heat-fused portion P where fibers between layers are bonded to each other. The "interlayer fiber intersection heat-fused portion P" refers to a portion where fibers are heat-fused at the intersection by a fluid (hot air, steam, etc.). Such an interlayer fiber intersection heat-fused portion P is formed when the first fiber layer 11 and the second fiber layer 22 contain thermoplastic fibers, and the thermoplastic fibers present at the interface between the layers are melted and bonded by the fluid.

[0067] The "wall" refers to a material with a resistance of 0.5gf / cm 2 When the nonwoven fabric 20 under load is viewed along the vertical direction (thickness direction Z) connecting the aforementioned flat plates (see the above-mentioned (Method of measuring the heights H1, H2, H3 of the uppermost convex portion 15, the first intermediate convex portion 1A, and the second intermediate convex portion 5A, respectively)), the fiber layer portion is identified as follows. 16, the fiber layer portion within the range of lengths HB1, HB2 in the thickness direction Z between the lowest points E3, E4 on the front side 20T of each bottom portion 2, 2B and the highest points E1, E2 on the back side 20B of each uppermost convex portion 15, 215 is referred to as the "wall portion." According to the above criteria, the wall portion 11B of the uppermost convex portion 15 of the first fiber layer 11 and the wall portion 22B of the uppermost convex portion 215 of the second fiber layer 22 are specified. In this definition, it is preferable that an overlap I of the lengths HB1 and HB2 in the thickness direction Z exists between the wall 11B of the uppermost convex portion 15 of the first fiber layer 11 and the wall 22B of the uppermost convex portion 215 of the second fiber layer 22. In the overlap, it is preferable that at least a part or all of the interlayer fiber intersection heat-bonded portion P, where the fibers between the layers are bonded, is included in the interface between the wall 11B and the wall 22B.

[0068] 16, the first fiber layer 11 on the front side 20T of the wall portion 11B, which is divided according to the above criteria, is referred to as a top portion 11A, and the first fiber layer 1 on the back side 20B of the wall portion 11B is referred to as a bottom portion 11C. The bottom portion 11C includes a fiber layer located at the bottom portion 2 of the first fiber layer 1. Similarly, the second fiber layer 22 on the front side 20T of the wall portion 22B, which is divided according to the above criteria, is referred to as a top portion 22A, and the second fiber layer 22 on the back side 20B of the wall portion 22B is referred to as a bottom portion 22C. The bottom portion 22C includes a fiber layer located at the bottom portion 2B of the second fiber layer 2.

[0069] It is preferable that the interlayer fiber intersection heat-bonded parts P are included in the interface between the wall part 11B of the top convex part 15 of the first fiber layer 11 and the wall part 22B of the top convex part 215 of the second fiber layer 22. This firmly bonds and fixes the walls 11B and 22B to each other, so that when the stacked top convex part 4 of the nonwoven fabric 20 (top convex part 15+top convex part 215) is deformed by pressure, the walls 11B and 22B interfere with and support each other, making them less likely to be crushed. That is, the interlayer intersection heat-bonded parts P enhance the pressure resistance of the stacked top convex part 4 of the nonwoven fabric 20. For the reasons described above, the ratio (former / latter) of the length G in the thickness direction Z of the interface between layers at the interlayer fiber intersection heat-fused zones P where the fibers are joined to the length F in the thickness direction Z between the highest point E1 on the back side 20B of the uppermost convex portion 15 of the first fiber layer 11 and the lowest point E4 on the front side 20T of the bottom portion 2B of the second fiber layer 22 is preferably 0.2 or more and 0.9 or less, more preferably 0.4 or more and 0.8 or less. Furthermore, if an interlayer fiber intersection heat-fused portion P is also included in the interface between the bottom portion 2 of the first fiber layer 11 and the bottom portion 2B of the second fiber layer 22, the aforementioned pressure resistance is further improved, which is preferable.

[0070] In addition, the wall fiber orientation degree is preferably 0.70 or more and 0.99 or less in the wall 11B of the top convex portion 15 of the first fiber layer 11. This wall fiber orientation degree is a value measured based on a method described later in a cross section of the thickness direction Z of the top convex portion 15. The higher the wall fiber orientation degree obtained by this measurement method, the more fibers are aligned along the extension direction V toward the top 11A of the wall 11B (see FIG. 20). When the wall fiber orientation degree is 0.7 or more, the wall 11B connecting the top 11A and the bottom 11C of the top convex portion 15 has high pressure resistance against pressure from the top 11A. This improves the thickness shape retention of the laminated top convex portion 4 (top convex portion 15 + top convex portion 215) of the nonwoven fabric 20. On the other hand, when the wall fiber orientation degree is 1, the fibers are aligned in one direction, so that the probability of fibers crossing each other in the layer is reduced. That is, the density of the fiber fusion points is reduced. Generally, when the wall fiber orientation degree is high, the fibers are aligned in the extension direction V, and the stiffness component due to the fibers themselves in the extension direction V is increased. However, conversely, the probability of fiber intersection is reduced, and the density of the fiber intersection heat fusion parts of each layer is reduced. In contrast, in this embodiment, in order to increase the total stiffness of the nonwoven fabric, the wall fiber orientation degree in the wall portion 11B is set to 0.99 or less, thereby increasing the orientation of the fibers in the extension direction V and the probability of fibers crossing each other, and suitably increasing the density per unit volume of the fiber intersection heat fusion parts of each layer. As a result, the wall portion 11B has high deformability and high stiffness when the uppermost convex portion 15 is compressed. The uppermost convex portion 15 of the first fiber layer 11 supported by the wall portion 11B has both a soft feel that is not too hard and thickness shape retention. That is, the uppermost convex portion 15 of the first fiber layer 11 has a firm presence and a stable thickness, while being soft due to the arch shape of the fiber network structure. From this viewpoint, the wall fiber orientation degree of the walls 11B of the uppermost convex portions 15 of the first fiber layer 11 is preferably 0.73 or more, more preferably 0.75 or more, and even more preferably 0.78 or more. Moreover, the wall fiber orientation degree of the walls 11B of the uppermost convex portions 15 of the first fiber layer 11 is preferably 0.95 or less, more preferably 0.90 or less, and even more preferably 0.81 or less.

[0071] In addition, the ratio of the wall fiber orientation degree at the top convex portion 15 of the first fiber layer 11 to the wall fiber orientation degree at the top convex portion 215 of the second fiber layer 22 (the former / the latter) is 1.1 or more and 1.5 or less. This means that the fibers of the wall portion 11B of the top convex portion 15 of the first fiber layer 11 are more aligned in the wall extension direction V than the wall portion 22B of the top convex portion 215 of the second fiber layer 22. When the wall fiber orientation degree ratio is high at 1.1 or more, the first fiber layer 11 deforms softly with a low load in the initial deformation when pressure is applied. Furthermore, when the wall fiber orientation degree ratio is 1.5 or less, the second fiber layer 22 is compressed while rebounding with high rigidity when pressed. In other words, the soft feel and thickness shape retention of the top convex portion 15 of the first fiber layer 11 are enhanced, while the top convex portion 215 of the second fiber layer 22 has a relatively diverse fiber orientation direction and has thickness recovery force. The uppermost convex portion 215 of the second fiber layer 22 conforms to the shape of the uppermost convex portion 15 of the first fiber layer 11, supports it from the inside, and imparts elasticity, thereby acting as a cushion in the stacked uppermost convex portion 4 (uppermost convex portion 15+uppermost convex portion 215). In particular, when the wall fiber orientation ratio is 1.1 or more, the hardness of the nonwoven fabric 20 can be suppressed, and the soft cushioning properties can be enhanced. Furthermore, when the wall fiber orientation ratio is 1.5 or less, the thickness of the nonwoven fabric 20 is easily maintained, and it is difficult to be crushed. From this viewpoint, the wall fiber orientation ratio is preferably 1.2 or more, and more preferably 1.4 or less.

[0072] The nonwoven fabric 20 has the above-mentioned fiber structure, and is characterized in that it has a soft deformability of the fiber layer while easily retaining a thickness shape under pressure. In addition, during the production of the nonwoven fabric 20, the first fiber layer 11 is shaped by the above-mentioned meshing. This shaping (independent two-stage meshing shaping) prevents excessive compression force from being applied to the unfused web, and the fiber density in each layer is not excessively increased, and a mesh structure with fibers appropriately spaced apart can be suitably formed. The nonwoven fabric 20 has such a mesh structure on the surface side 20T, and is bulky and thick. That is, the nonwoven fabric 20 has a bulky and thick fiber structure while having soft and good cushioning properties, and the thickness can be maintained under pressure use, and is difficult to be crushed. In addition, as described above, the first fiber layer 11 of the nonwoven fabric 20 is easily deformed by a weak force. As a result, the second fiber layer 2 maintains the unevenness of the nonwoven fabric 20, while the first fiber layer 1 absorbs the unevenness by its deformation, thereby reducing the uneven feeling when touching the front side 20T of the nonwoven fabric 20, and at the same time, improving the smoothness when stroking the surface of the uppermost convex portion 15. As a result, the nonwoven fabric 20 has both thickness shape retention and smoothness in an uneven structure, which were difficult to achieve in the past. At the same time, it has an appropriate compression energy and is excellent in texture.

[0073] In the nonwoven fabric 20 of this embodiment, in the laminated uppermost convex portion 4 having a unique structure relating to the wall fiber orientation degree, it is preferable that a moderate amount of voids 8 is interposed between the first fiber layer 11 and the second fiber layer 22. The voids 8 referred to here are portions having an extremely small amount of fiber compared to the first fiber layer 11 and the second fiber layer 22, and can be defined as regions in which the fiber density of the voids 8 is 10% or less when the lower fiber density of the uppermost convex portion of each fiber layer (and further the central portion in the thickness direction) is taken as 100%, and are preferably spaces without fibers. As a result, a primary storage space for bodily fluids and the like is formed within the uppermost convex portion 4 of the laminate. For example, when the nonwoven fabric 20 is used as a top sheet that comes into contact with the skin of an absorbent article, the absorbency of the absorbent article can be improved, and the dryness of the skin surface can be improved. Furthermore, when the voids 8 are present at an appropriate size, the nonwoven fabric 20 can withstand a low load (for example, a load of 0.5 gf / cm2 to 10 gf / cm2) in the initial deformation stage. 2 It is soft under high loads (for example, 10 gf / cm 2 Load from 50gf / cm 2 In the range of load (up to the load range), the second fiber layer 22, which is the lower layer, contributes to the collapse. From the above viewpoints, in a cross section in the thickness direction on a line including the center of the uppermost convex portion 15 (the center of the apex 11A of the uppermost convex portion 15) and the center of the bottom portion 2 adjacent to the uppermost convex portion 15, obtained by the (method of measuring the void ratio) described later, the void ratio (area ratio of the void portion 8) between the first fiber layer 11 and the second fiber layer 22 is preferably 3% or more, more preferably 4% or more, and even more preferably 8% or more, from the viewpoint of enhancing the deformability of the nonwoven fabric 20 by pressure application and making it feel softer. Moreover, from the viewpoint of making the entire thickness of the nonwoven fabric 20 less likely to be crushed under a high load, the void ratio is preferably 13% or less, and more preferably 10% or less. In the initial low-load pressure crush, the first fiber layer 11 deforms softly to become soft, and then, under a high load after the void portions 8 disappear due to crushing, the second fiber layer 22 deforms together with the first fiber layer 11, making the nonwoven fabric 20 less likely to be crushed. From this viewpoint, the void ratio of void portion 8 is preferably 3% or more and 13% or less, and more preferably 4% or more and 10% or less. When nonwoven fabric 20 has the above-mentioned intermediate convex portions (first intermediate convex portion 1A, second intermediate convex portion 5A, first intermediate convex portion 21A, second intermediate convex portion 25A), it is preferable that void portion 8 is not present in the laminated portion of the intermediate convex portions.

[0074] The above void ratio can be appropriately set by controlling the amount of meshing in the manufacturing process described above. That is, from the viewpoint of providing an appropriate amount of voids 8 between the first fiber layer 11 and the second fiber layer 22, the nonwoven fabric 20 preferably has a ratio of the wall fiber orientation degree at the uppermost convex portion 15 of the first fiber layer 11 to the wall fiber orientation degree at the uppermost convex portion 215 of the second fiber layer 22 described above.

[0075] The method for producing a nonwoven fabric of the present invention is not limited to laminating only one type of unfused web of the first embodiment or two types of unfused webs of the second embodiment. For example, a step of laminating another unfused web or nonwoven fabric after step (1-2) or (2-2) may be included. In this case, the heat treatment step (1-3) or (2-3) is carried out after this. This allows the nonwoven fabric of the present invention to have a flat third fiber layer, which prevents the projections from being crushed due to stretching in the width direction when wound. Furthermore, the method for producing a nonwoven fabric of the present invention is not limited to a two-stage intermeshing shaping step, and may involve three or more stages of intermeshing shaping steps.

[0076] Next, specific examples (Specific Example 1 and Specific Example 2) of a preferred manufacturing apparatus used in the manufacturing method of the nonwoven fabric of the present invention will be described with reference to FIGS.

[0077] The nonwoven fabric manufacturing apparatus 900 of Example 1 shown in Fig. 17 uses a drum-shaped support 110 with an uneven peripheral surface as a support for performing two-stage meshing shaping. A first pushing member 120A and a second pushing member 120B are disposed on the peripheral surface of the support 110 so as to be capable of meshing with each other. The first pushing member 120A and the second pushing member 120B are formed in a roll shape. First, the unfused web 100 is fed between the support 110 and the first pushing member 120A, and the above-mentioned first shaping step is carried out by the engagement between the support 110 and the first pushing member 120A. Next, the second shaping step is carried out by meshing between the support 110 and the second pushing member 120B. In the nonwoven fabric method of the first embodiment, the second shaping step is carried out only on the unfused web 100 that has been subjected to the first shaping step. In the nonwoven fabric manufacturing method of the second embodiment, the second unfused web 200 is laminated on the unfused web (first unfused web) 100 that has been subjected to the first shaping step on the support 110, and then the second shaping step is carried out.

[0078] The convex or concave portions of the support 110 extend in the machine flow direction (the direction of rotation of the drum shape), and also extend in the width direction (the direction of the rotation axis of the drum shape) perpendicular to the machine flow direction. It is preferable that the support 110 applies negative pressure from the circumferential surface to the inside. This allows the first unfused web 100 and the second unfused web 200 aligned along the circumferential surface of the support 110 to be sucked, and the aligned state can be maintained better before moving to the next process.

[0079] Next, while the unevenly textured unfused web 100 (first embodiment) or the unevenly textured laminate of the first unfused web 100 and the second unfused web 200 (second embodiment) is held on the peripheral surface of the support 110, hot air W1 is blown at the hot air blowing section 140 to perform fiber fusion using a heated fluid (heat treatment step). Alternatively, in the second shaping step, a heat treatment step using hot air blowing may be performed simultaneously with shaping. In this way, the nonwoven fabric 10 or the nonwoven fabric 20 described above is manufactured.

[0080] When the hot air W1 is blown, it is preferable to hold down the unevenly shaped unfused web 100 or the entire laminate of the first and second unfused webs with a net 130. This makes it possible to prevent the fibers from scattering when the hot air W1 is blown. It is also preferable to have a hot air suction section 141 inside the drum of the support 110 at a position opposite to the hot air blowing section 140.

[0081] The temperature of the hot air W1 is preferably 140° C. or higher, more preferably 145° C. or higher, and even more preferably 150° C. or higher, from the viewpoint of thermally fusing the thermoplastic fibers and stabilizing the shape of the nonwoven fabric. The temperature of the hot air W1 is preferably 180° C. or lower, more preferably 175° C. or lower, and even more preferably 170° C. or lower, from the viewpoint of preventing excessive thermal fusion of the thermoplastic fibers and improving the softness of the nonwoven fabric. In addition, the wind speed of the hot air W1 is preferably 15 m / sec or less, more preferably 12 m / sec or less, and even more preferably 10 m / sec or less, from the viewpoints of improving cushioning properties and enhancing the retention of the overall thickness of the nonwoven fabrics 10 and 20. Moreover, the wind speed of the hot air W1 is preferably 2 m / sec or more, more preferably 3 m / sec or more, and even more preferably 4 m / sec or more, from the viewpoints of thermally fusing the thermoplastic fibers and stabilizing the shape of the nonwoven fabric.

[0082] In the nonwoven fabric manufacturing apparatus 900 of Example 1, it is preferable to arrange a cooling section 150 having a cooling nozzle and a cooling suction section 151 inside the drum of the support 110 opposite each other at a position where the nonwoven fabrics 10 and 20 obtained by blowing the hot air W1 are arranged along the outer periphery of the drum of the support 110. This makes it possible to keep the support 1 at a certain temperature or lower, as described above, and the obtained nonwoven fabric can be peeled off while maintaining its shape, thereby maintaining good cushioning properties.

[0083] After the hot air W1 treatment, it is preferable to carry out an air-through treatment (hot air treatment) on a net.

[0084] Each of the above steps can be carried out under various conditions, etc. For example, the various conditions described in paragraphs

[0010] to

[0067] of the specification of JP-A-2019-112747 can be appropriately adopted. Various forms of the support 110 and the pushing members 120A and 120B can be used. For example, the support shown in FIG. 2 in the above-mentioned document can be used. The pushing member can be a combination of a ring-shaped roll shown in FIG. 8 in the above-mentioned document and a gear roll or a blade. The support shown in FIG. 2 is a drum-type support having convex parts, concave parts and apertures on the circumferential surface. A plurality of convex parts are arranged on the circumferential surface of the support, spaced apart from each other in the rotation direction and the rotation axis direction. As a result, the concave parts extend in the rotation direction and the rotation axis direction of the support. The pushing member shown in FIG. 8 is a drum-shaped member in which a plurality of rings are combined in the rotation axis direction, and the ring part forms a pushing part extending in the rotation direction.

[0085] Furthermore, the nonwoven fabric manufacturing apparatus 900 of Example 1 may have a mechanism for laminating another unfused web or nonwoven fabric (web 300) after peeling the nonwoven fabric 10 from the peripheral surface of the support 110. In this case, it is preferable to have another mechanism for carrying out a heat treatment step thereafter.

[0086] 18 includes a web supply section 102 that supplies an unfused web 100, a conveyor belt 104 that transports the unfused web 100 supplied from the web supply section 102, and a nip roller 106 that pressurizes the unfused web (or first unfused web) 100 transported by the conveyor belt 104. Downstream of the above, there are a pair of rolls (support 110 and first pushing member 120A) that perform a first shaping step on the unfused web 100, and a roll (second pushing member 120B) that performs a second shaping step on the peripheral surface of the support 110. In the first embodiment, this second shaping step is performed only on the unfused web 100. In the second embodiment, a second unfused web 200 is laminated on a support 110 onto an unfused web (first unfused web) 100 that has been subjected to a first shaping step, and then the second shaping step is started. Further downstream, there is provided a point bonding means 130 for bonding some or all of the fibers at the bottom of the recesses of the uneven unfused web 100 (first embodiment) or the uneven laminate of the first unfused web 100 and the second unfused web 200 (second embodiment) pulled by the support 110. The heat treatment step is performed by this point bonding means 130. Alternatively, the second shaping step may be performed in the above-mentioned roll 120B, and the heat treatment step may be performed by embossing at the same time. Further downstream, there is provided a cooling roll 114 for cooling the fused portion (embossed portion) fused by the point bonding means 130. Further downstream of the cooling roll 114, there is a heat flow section 118 for spraying a heated fluid to fuse fiber intersections, i.e., to form a nonwoven fabric.

[0087] The web supply unit 102, the conveyor belt 104, and the nip roller 106 are configured to supply and transport the first unfused web 100 toward the support 110 and the first pushing member 120A. The cooling roll 114 is configured to transport the laminate of the first unfused web 100 and the second unfused web 200 on which the embossed portion 6 is formed by the point joining means 130 toward the downstream side while cooling it. The conveyor belt 104, the nip roller 106, and the cooling roll 114 may not be used as appropriate, but it is preferable to provide them for stable production. As the web supply unit 102, the conveyor belt 104, the nip roller 106, and the cooling roll 114, various configurations that are usually used can be adopted.

[0088] In the manufacturing apparatus 910 having the above configuration, first, the unfused web 100 is supplied from the web supply unit 102 onto the conveyor belt 104, and the unfused web 100 is conveyed between the support 110 and the first pushing member 120A by the conveyor belt 104 while being pressed by the nip roller 106. Here, the nip roller 106 does not firmly bond the fibers, but presses the fibers together to such an extent that the unfused web 100 can be conveyed. Most of the pressed parts at this time tend to peel off due to the tensile force when the support 110 and the first pushing member 120A are engaged. In this way, the peeling reduces the number of pressed parts, which increases the freedom of the fibers and provides an excellent texture, and is therefore preferable. Even if a part of the pressed part remains, the pressed part is not a fused part, and therefore there is almost no deterioration in texture due to catching.

[0089] In addition, in the nonwoven fabric manufacturing apparatus 910 of Example 2, the web supply unit 102 is shown as supplying a single-layer unfused web 100, but is not limited thereto. For example, the web supply unit 102 may include two or more devices so as to be able to supply an unfused web 100 having a thickness of two or more layers. When the first unfused web 100 is supplied onto the conveyor belt 104 as a laminate of two or more layers, in the manufacturing apparatus 910, the support 110 and the first pushing member 120A impart unevenness to the entire laminate.

[0090] In the nonwoven fabric manufacturing apparatus 910 of Example 2, similar to the nonwoven fabric manufacturing apparatus 900 of Example 1 described above, the first shaping process and the second shaping process described above are carried out by meshing between the support 110 and the first pushing member 120A and the second pushing member 120B. The unevenly formed unfused web 100 or the unevenly formed laminate of the first unfused web 100 and the second unfused web 200 is brought into close contact with the peripheral surface of the support 110 by frictional force with the support 110, suction, or the like, and is conveyed to the position of the point joining means 130 while maintaining the uneven shape formed by the rotation of the support 110. The fibers at the bottom of the recesses of the laminate are embossed and pressed or embossed and fused by the clamping between the point joining means 130 and the protruding or recessed parts of the support 110. The embossing method can use pressure by a heated roll or pressure by an ultrasonic roll or ultrasonic horn. As a result, the embossed part 6 is formed in a predetermined pattern. Thereafter, the laminate is delivered to the cooling roll 114 and cooled, and is conveyed by the second conveyor belt 117 downstream of the cooling roll 114, where the fiber intersections are fused at the heat flow part 118 (heat treatment process). In this way, the nonwoven fabric 10 or the nonwoven fabric 20 described above is manufactured.

[0091] Furthermore, the nonwoven fabric manufacturing apparatus 910 of Example 2 may have a mechanism for merging and laminating the unevenly textured laminate of the first unfused web 100 and the second unfused web 200 with another unfused web or nonwoven fabric (web 300). In this case, an embossed portion is formed by point joining means 130 in a state where the laminate and web 300 are laminated.

[0092] The nonwoven fabric obtained by the method for producing a nonwoven fabric of the present invention can be used for various purposes. For example, the nonwoven fabric of the present invention can be used in absorbent articles such as diapers, sanitary napkins, panty liners, and urine pads. Absorbent articles typically have a liquid-permeable top sheet, a back sheet, and an absorbent sandwiched between them. The nonwoven fabric of the present invention can be particularly suitably used as a top sheet. Furthermore, the nonwoven fabric of the present invention can also be used as a sheet in the gather part, an exterior sheet, or a sheet in the wing part of an absorbent article. It can also be used as a sweat-absorbing sheet or as a component of an eye mask or mask. In either application, in the nonwoven fabric manufacturing apparatus 900 of Example 1 and the nonwoven fabric manufacturing apparatus 910 of Example 2, it is preferable in terms of texture that the side in contact with the support 110 is the skin-facing side. EXAMPLES

[0093] The present invention will be described in more detail below based on examples, but the present invention is not limited thereto. In the examples, "parts" and "%" are all based on mass unless otherwise specified. In Table 1 below, "-" means that the item does not have a corresponding item or value.

[0094] Example 1 A first unfused web 100 and a second unfused web 200 were each prepared as described below. Thermoplastic concentric composite short fibers of a core-sheath type (polyethylene terephthalate (PET) (core):polyethylene (PE) (sheath) = 5:5 (mass ratio)) with a fineness of 1.1 dtex were used for the first unfused web 100. Thermoplastic concentric composite short fibers of a core-sheath type (polyethylene terephthalate (PET) (core):polyethylene (PE) (sheath) = 5:5 (mass ratio)) with a fineness of 3.3 dtex were used for the second unfused web 200. Both were coated with a hydrophilic oil agent. The first unfused web 100 (basis weight 15 g / m 2 ) and the second unfused web 200 (15 g / m 2 ) was formed. A support roll having the convex portion arrangement shown in FIG. 1 on its peripheral surface was used as the support, a ring-shaped roll was used as the first pushing member, and a gear roll using a blade was used as the second pushing member. The first unfused web 100 was subjected to a first shaping step on the support by meshing the first pushing member with the support. Thereafter, the second unfused web 200 was laminated on the previously shaped first unfused web 100, and the laminated web was subjected to a second shaping step on the support by meshing the second pushing member with the support. The respective conditions were as shown in Table 1. The interlocking laminate was placed on the support and hot air (temperature 160°C, wind speed 4.3 m / s, blowing time 1.5 seconds) was blown from the second unfused web side to perform fiber intersection fusion treatment. Thereafter, the interlocking laminate was peeled off from the support and hot air treatment was performed on the surface (first fiber layer) side on a conveyer net at a hot air temperature of 136°C, wind speed of 1.5 m / s, and blowing time of 6 seconds to form fiber intersection heat-fused parts. In this way, a nonwoven fabric sample of Example 1 was produced. FIG. 19 shows images of each cross section of the nonwoven fabric sample obtained by the above manufacturing method of the Example taken with a microscope at a magnification of 20 times. In each cross section, the outer edges of the first fiber layer 11 and the second fiber layer 22 were traced with a felt tip pen. The above images were taken with a plate at a "0.5 gf / cm 2 The test was carried out under "load". The obtained nonwoven fabric sample had two fiber layers laminated in the thickness direction, and the first fiber layer 11 on one side and the second fiber layer 22 adjacent to the first fiber layer 11 on the other side in the thickness direction each had the above-mentioned uneven shape. The second fiber layer 22 had an uppermost convex portion 215 extending into the other side of the uppermost convex portion 15 of the first fiber layer 11. At least the interface between the wall portion 11B of the uppermost convex portion 15 of the first fiber layer 11 and the wall portion 22B of the uppermost convex portion 215 of the second fiber layer 22 contained an interlayer fiber intersection heat-fused portion P. In the wall portion 11B of the uppermost convex portion 15 of the first fiber layer 11, the aforementioned wall fiber orientation degree was 0.70 or more and 0.99 or less, and the ratio of the wall fiber orientation degree in the uppermost convex portion 15 of the first fiber layer 11 to the wall fiber orientation degree in the uppermost convex portion 215 of the second fiber layer 22 (former / latter) was 1.1 or more and 1.5 or less. The obtained nonwoven fabric sample had clearly formed vertical rib portions 1 and horizontal rib portions 5, and the height H2 of the first intermediate convex portion 1A was higher than the height H3 of the second intermediate convex portion 5A, but the value of {|H2-H3| / H1}×100 was smaller than that of the comparative example.

[0095] Comparative Example 1 A ring-shaped roll was used as the first pushing member, a ring-shaped roll was used as the second pushing member, the meshing direction and meshing amount of the first pushing member and the second pushing member were as shown in Table 1, and the meshing amount ratio was 1.1. Except for this, a nonwoven fabric sample of Comparative Example 1 was produced in the same manner as in Example 1. The hot air treatment for each sample was performed under the same conditions as in Example 1.

[0096] Comparative Example 2 A nonwoven fabric sample of Comparative Example 2 was produced in the same manner as in Example 1, except that the second shaping step was not performed, and the second unfused web was not interlocked and shaped, and was laminated in a flat shape. Each hot air treatment was performed under the same conditions as in Example 1.

[0097] Comparative Example 3 The first unfused web and the second unfused web used in Example 1 were not subjected to meshing shaping, but were subjected to shaping by two-stage hot air blowing to prepare a nonwoven fabric sample of Comparative Example 3. The two-stage hot air blowing was performed as follows. That is, the first unfused web 100 was placed on the support, and hot air was blown from the web side at a temperature of 160°C, a wind speed of 6 m / s, and a blowing time of 0.2 seconds, to perform hot air shaping and fiber intersection fusion treatment, to obtain a first fused web. Thereafter, the second unfused web 200 was laminated thereon, and hot air was blown from the second unfused web 200 side at a temperature of 160°C, a wind speed of 2 m / s, and a blowing time of 1.5 seconds to the laminate of the first fused web and the second unfused web 200 placed on the support, to perform hot air shaping and fiber intersection fusion treatment. Thereafter, the laminated web shaped by hot air was peeled off from the support, and hot air treatment was performed from the back surface (second fiber layer) side on a conveyer net at a hot air temperature of 136°C, a wind speed of 1.5 m / s, and a blowing time of 6 s to form heat-fused fiber intersections. A nonwoven fabric sample of Comparative Example 3 was produced in the same manner as in Example 1 except for the above.

[0098] The nonwoven fabric samples of each of the Examples and Comparative Examples were subjected to the following tests [1] to [6]. [1] The wall fiber orientation degree and wall fiber orientation angle in the uppermost convex parts 15 and 215; the fiber density of the uppermost convex parts 15 and 215; the bulk density of the nonwoven fabric The measurements were made based on the following (Method of measuring the wall fiber orientation degree and wall fiber orientation angle in the uppermost convex portions 15 and 215) and (Method of measuring the fiber density).

[0099] (Method of measuring wall fiber orientation degree and fiber orientation angle in uppermost convex portions 15 and 215) The wall fiber orientation degree and wall orientation angle of the uppermost convex portion 15 of the first fiber layer 11 and the uppermost convex portion 215 of the second fiber layer 22 were measured by the following method. (1) The sample was cut in an arbitrary planar direction using sharp scissors. The cut position was set to pass through the center of the apex 11A of the top convex portion 15 of the sample and the center of the bottom portion 2 adjacent to the top convex portion 15. When the sample was cut in a direction parallel to the CD direction, the cross section in the CD direction was taken, and when the sample was cut in the MD direction or diagonal direction, the cross sections in the respective directions were taken. (2) The sample was cut into a rectangle so that each side contained at least five uppermost convex portions 15, and a cross-sectional sample was prepared. The target convex portions were observed at least one convex portion inside the cut position of the corner of the sample. When the target nonwoven fabric was bonded to another layer, it was observed while still bonded to the other layer. (3) Place the cross-sectional sample on a flat plate with the top convex portion 15 (front surface side 20T) facing up, and apply 0.5 gf / cm 2 A flat plate was placed on top of the sample so that the cross section of the sample coincided with the end faces of both plates. (4) Next, the cross section of the cross section sample is observed from the side. Using a microscope, the observation magnification is 100x to 400x, quick synthesis (depth UP, quick synthesis & 3D) is performed, the sample is moved from the back to the front, observed, and an image is taken. As an example of the microscope, VHX-6000 (product name) manufactured by Keyence Corporation was used. (5) Using the images obtained by observation, the following measurements were made (see Figures 16, 20 and 21). In the wall portions 11B, 22B of the uppermost convex portions 15, 215 to be observed in the image, a square E was marked at the middle position L1 in the direction of the actual thickness of each fiber layer (the direction perpendicular to the extending direction V of each fiber layer in the wall portion) S, and at the middle height position (M1, M2) of the length HB1, HB2 in the thickness direction Z between the lowest points E3, E4 of the front side 20T of each bottom portion 2, 2B and the highest points E1, E2 of the back side 20B of each uppermost convex portion 15, 215. The size of the square E was smaller than the actual thickness, and was set to a size such that five or more fibers could be contained within the square. The size of the square E may be different between the first fiber layer 11 and the second fiber layer 22. The square E was tilted so that one side was parallel to the extending direction V (the direction perpendicular to the actual thickness) in each fiber layer. The fibers in square E were traced to extract the fibers that crossed from one side to the other. At this time, fibers that crossed only one side and were interrupted along the way were excluded. In the square E, A / (A+B) was calculated from the number A (the sum of the two sides) of fibers intersecting with the side EA perpendicular to the extension direction V of the fiber layer and the number B (the sum of the two sides) of fibers intersecting with the side EB parallel to the extension direction V of the fiber layer. This value was taken as the wall fiber orientation degree at the uppermost convex part of each fiber layer. A higher wall fiber orientation degree means that the fibers are more oriented in the extension direction V of the fiber layer. In addition, the direction perpendicular to the plane of the nonwoven fabric (total thickness direction) was defined as 90 degrees, and the plane direction was defined as 0 degrees, and the inclination angle of the side EB of the square E parallel to the extending direction V of the fiber layer was determined. This value was defined as the orientation angle of each fiber layer in the wall portions 11B and 22B (hereinafter also referred to as the wall portion fiber orientation angle). Each value was calculated as the average value of five points using different sample sides. (6) The boundary between the laminated first fiber layer 11 and second fiber layer 22 can be identified by differences in layer structure, such as differences in fiber diameter, differences in fiber orientation, differences in fiber cross-sectional shape, voids between layers, differences in fiber density, differences in the number of fibers per unit area, differences in basis weight, etc. (7) The total thickness T0 of the nonwoven fabric was calculated as follows. Two straight lines were measured on the sample surface side between the upper and lower flat plates of the sample in the cross section of the sample. The average distance between these two straight lines in the thickness direction of the nonwoven fabric was calculated, and this was defined as the total thickness T0 of the nonwoven fabric.

[0100] (Method of measuring fiber density of uppermost convex portions 15 and 215) Using a scanning electron microscope (SEM), the sample was subjected to the minimum necessary amount of gold sputter deposition at a magnification of 100x to 700x. In a cross section prepared by the method described below (method of measuring void ratio), the number of cut ends of the fibers was counted at the center position of the actual thickness of each layer and at the position of the uppermost convex part of each fiber layer. The measurement range was a square with one side being 50% to 80% of the actual thickness of each layer. The cross section of the fiber was divided by the area of ​​the square to obtain the fiber density (fibers / mm 2 ) was sought. Each value was the average value of five points using different sample sides.

[0101] (Method of measuring bulk density of nonwoven fabric (fiber density of entire nonwoven fabric)) The bulk density of a nonwoven fabric means the apparent fiber density, and was calculated as the density including the hollow parts (voids 8 described below). Specifically, the nonwoven fabric to be measured was cut to 250 mm x 250 mm, and its mass was measured. If the sample area is smaller than this, it is measured with an appropriate possible size. The mass was divided by the cut cross-sectional area of ​​the sample to obtain the basis weight (g / m 2 The number of measurements, n, was set to 3, and the average value was taken as the basis weight of the nonwoven fabric being measured. 2 ) to the above 0.5gf / cm 2 Dividing the total thickness of the nonwoven fabric under load (m) gives the bulk density of the nonwoven fabric (g / m 3 The bulk density indicates the degree of bulkiness of the nonwoven fabric.

[0102] In the nonwoven fabric, when the bulk density is appropriately small, the nonwoven fabric has a high volume and a soft cushioning property. The bulk density of the nonwoven fabric is preferably 0.003 g / m 3 More than 0.006g / m 3 Less than or equal to 0.0035 g / m 3More than 0.005g / m 3 The following is preferable in terms of providing a good texture.

[0103] [2] Interlayer fiber intersection heat fusion part P 0.5gf / cm 2 In the cross section of each nonwoven fabric under load in the thickness direction Z, the length in the thickness direction Z between the highest point E1 on the back side 20B of the uppermost convex portion 15 of the first fiber layer 11 and the lowest point E4 on the front side 20T of the bottom portion 2B of the second fiber layer 22 was defined as F, as shown in Fig. 16. The length in the thickness direction Z of the interface between each layer at the interlayer fiber intersection heat-fused portion P where the fibers are bonded to each other was defined as G (the length in the thickness direction between points E5-E4). These values ​​were determined by the same method as the method for measuring the void ratio (area ratio of void portions 8) described later.

[0104] [3] Height of each protrusion in the first fiber layer and the second fiber layer The measurements were made based on the above-mentioned (method of measuring the heights H1, H2, and H3 of the uppermost convex portion 15, the first intermediate convex portion 1A, and the second intermediate convex portion 5A, respectively).

[0105] [4] Area ratio of the gap 18, the first fiber layer 11, the void portion 8, the second fiber layer 22, and the gap 28 in a cross section including the uppermost convex portion 4 of the laminate The measurement was performed based on the following (Method of Measuring Void Ratio).

[0106] (Method of measuring void ratio) (1) Each nonwoven fabric to be measured was placed in an unloaded state with the uppermost convex portion 15 of the first fiber layer 11 facing up, and stored at a temperature of 23±2°C and a humidity of 65±5% RH for 48 to 72 hours. When the nonwoven fabric to be measured is bonded to another member (for example, when incorporated as a constituent member of an absorbent article), it can be sampled while still bonded to the other member. (2) The above sample was prepared into a rectangular shape with a length of 5 times the pitch of the top convex portion 15 (on the cut line 1 side) x 5 times the pitch of the top convex portion 15. In this case, in a plan view of the nonwoven fabric, one side was cut in the thickness direction with sharp scissors or the like, with the top convex portion 15 at the center, on a line including the center of the top convex portion 15 to be observed (the center of the top 11A of the top convex portion 15) and the center of the bottom portion 2 adjacent to the top convex portion 15. The direction of the cut line 1 can be the MD direction, the CD direction, or a diagonal direction. The cross section of the cut line 1 was colored with a marker or the like. (3) Observe the cross section of the unevenness from the cross section sample at the cut line 1. Place the cross section sample on a flat plate with the top convex part 15 facing up, and apply a load of 0.5 gf / cm 2 At this time, the position of the sample cross section and the end face of each flat plate were aligned. (4) The cross section of the sample was observed from the side using a microscope (e.g., VHX-6000 (product name) manufactured by Keyence Corporation). The three top convex portions 4 and the four bottom portions 2 and 2B located in the center of the sample aligned along the cut line 1 were observed at a magnification of 50 to 300 times. (5) Using the observed image, the boundaries of the first fiber layer 11 and the second fiber layer 22 were drawn with the colored portions as guides. When it was difficult to distinguish between the fiber layers, the boundaries were determined by the method described above in (Method of measuring the wall fiber orientation degree and wall fiber orientation angle). (6) In the observed image, the boundaries of each fiber layer are filled in black, and the other parts are painted white. Using image analysis software (for example, Image-Pro Plus (version: 6.2.0.424) as image analysis software), the area A (observation range) between the upper plate and the lower plate (stage) within the width of the observed image is obtained. The resolution of the image analysis software is 300 pixels / inch, and the area A is 100,000 to 200,000 pixels. 2 The size of the observed image was adjusted so that (7) In the cross-sectional region having the area A, the areas of the void 8 formed between the back side boundary of the first fiber layer 11 and the front side boundary of the second fiber layer 22, the gap 18 formed between the front side boundary of the first fiber layer 11, the second fiber layer 22, and the first fiber layer 11 and the upper plate, and the gap 28 formed between the back side boundary of the second fiber layer 22 and the stage were similarly determined (see, for example, FIG. 21). (8) The void ratio (area ratio of void portions 8) was calculated as "area of ​​void portions 8 / area A×100(%)". Similarly, the area ratios of the gaps 18, the first fiber layer 11, the second fiber layer 22, and the gaps 28 were also calculated. (9) Each value was calculated as the average of five values ​​using different sample sides.

[0107] [5] Friction characteristics, roughness characteristics and compression characteristics The following (Method of measuring friction characteristics), (Method of measuring roughness characteristics), (Method of measuring compression characteristics), (0.5gf / cm 2 The thickness of the nonwoven fabric under load was measured based on the method for measuring the total thickness of the nonwoven fabric under load. Having these properties within the following ranges contributes to improving the texture, which will be described later.

[0108] (Method of measuring friction characteristics) The mean coefficient of friction (MIU) and the mean deviation of the surface coefficient of friction (MMD) were measured by the following method. That is, an automatic surface tester (KES FB4-AUTO-A manufactured by Kato Tech Co., Ltd.) was used, and a gauge head made of a steel piano wire with a diameter of 0.5 mm was used to measure the surface area of ​​the gauge head of 1 cm. 2 , load 50gf / cm 2 The frictional force was measured when the sheet was moved back and forth over a length of 30 mm at a speed of 1 mm / s. The analysis distance was set to 20 mm by cutting 5 mm of data from both ends. The surface friction coefficient was calculated as MIU, and the average deviation of the surface friction coefficient as MMD. The surface side of the measurement surface was the probe side, the measurement directions were the X and Y directions, and the measured values ​​were averaged. The initial sample tension was 10 gf / cm. Each measurement value was calculated by measuring five points on the sheet and averaging the values.

[0109] In nonwoven fabrics, the average coefficient of friction (MIU) in a suitable range allows the fabric to have a good feel. From this viewpoint, the average coefficient of friction (MIU) is preferably 0.1 or more, more preferably 0.2 or more. This allows the fabric to have a soft feel like fibers, rather than a smooth feel like a film. Also, from the viewpoint of not having a sticking feel to the skin and not damaging the skin, the average coefficient of friction (MIU) is preferably 0.5 or less, more preferably 0.4 or less. In nonwoven fabrics, when the average coefficient of friction (MIU) is within the appropriate range and the mean deviation value of the coefficient of surface friction (MMD) is small, the fabric tends to have an appropriate smoothness. Appropriate smoothness makes the fabric feel good to the touch. From this viewpoint, the mean deviation value of the coefficient of surface friction (MMD) is preferably 0.001 or more, and more preferably 0.002 or more. Furthermore, the smaller the friction, the less likely the fabric will get caught even if the surface is uneven, and the smaller the variation in the coefficient of friction, making the fabric feel smooth. From this viewpoint, the mean deviation value of the coefficient of surface friction (MMD) is preferably 0.01 or less, and more preferably 0.008 or less.

[0110] (Method of measuring roughness characteristics) The mean deviation of surface roughness (SMD) was measured by the following method: using the above-mentioned automatic surface tester, a probe of width 5 mm made of a single steel piano wire of diameter 0.5 mm was applied under a load of 10 gf / cm. 2 The roughness was measured when the sheet was moved back and forth over a length of 30 mm at a speed of 1 mm / s. As with the friction characteristics, the average deviation of surface roughness within the analysis distance was calculated as SMD. The surface side of the measurement surface was the side facing the gauge, and the measurement directions were MD and CD, and the measured values ​​were averaged. The initial sample tension was 10 gf / cm. Each measurement value was calculated by averaging five points on the sheet.

[0111] In the nonwoven fabric, the apex 11A of the uppermost convex portion 15 has a suitable surface roughness, which gives a sense of unevenness when touched by hand, and gives a soft feel to the fibers. From this viewpoint, the surface roughness mean deviation (SMD) is preferably 0.1 μm or more, more preferably 0.2 μm or more, and even more preferably 0.3 μm or more. Furthermore, the smaller the surface roughness, the more gentle the contact with the skin can be maintained. From this viewpoint, the surface roughness mean deviation (SMD) is preferably 4 μm or less, more preferably 3.5 μm or less, and even more preferably 3.0 μm or less.

[0112] (Method of measuring compression characteristics) The compression properties were measured by the following method using the above-mentioned automatic compression tester at a speed of 0.05 mm / s and a probe area of ​​2 cm. 2 At a compression load of 0.5gf / cm 2 More than 50gf / cm 2 The sheet was compressed by the gauge in the following range, and the thickness and the load at that time were measured when the sheet was moved in the recovery direction immediately after applying the maximum load. 2 The thickness of the nonwoven fabric under load is T0, and the load is 50gf / cm 2 The thickness of the nonwoven fabric under load was defined as TM. The linearity of the compression characteristics was determined as LC, compression energy as WC, recovery energy as WC', compression resilience as RC(WC' / WC×100), and deformation amount as "T0-TM". The surface of the measurement was such that the surface side was the side of the gauge. Each measurement value was calculated by measuring five points on the sheet and averaging the results. The compression resilience RC (WC' / WC x 100) was calculated from the compression energy (WC) and recovery energy (WC'). If the nonwoven fabric to be measured is incorporated into a product, the adhesive strength of the adhesive or the like is weakened by a cooling means such as a cold spray, and the nonwoven fabric is removed from the product and the above measurements are performed. This method of removing the nonwoven fabric is similarly applied to other measurements in this specification. Unless otherwise specified, randomly selected locations are measured for each measurement.

[0113] In a nonwoven fabric, the greater the linearity (LC) of the compression characteristics at the uppermost convex portion 15, the more likely it is that the thickness will remain when pressed, and the better the rebound when pressed with the skin of the hand, i.e., the better the cushioning will feel. From this viewpoint, the linearity (LC) of the compression characteristics at the uppermost convex portion 15 is preferably 0.3 or more, and more preferably 0.4 or more. Also, since there is a tendency for a material to be perceived as being good when it is initially deformed by a soft force and has a higher rebound force as the amount of compression increases, the linearity (LC) of the compression characteristics at the uppermost convex portion 15 is preferably 0.5 or less, and more preferably 0.45 or less.

[0114] In the nonwoven fabric, if the compression energy (WC) at the uppermost convex portion 15 is not too high or too low, the resistance to deformation when pressed by hand becomes appropriate, resulting in a soft texture. From this viewpoint, the compression energy (WC) at the uppermost convex portion 15 is set to 4.5 gfcm / cm 2 More than 5.0gfcm / cm is preferable. 2 More preferably, from the viewpoint of suppressing the repulsive force and maintaining a suitable texture, the compression energy (WC) at the convex portion is 8 gfcm / cm 2 Less than 7gfcm / cm is preferable. 2 It is more preferable that:

[0115] Furthermore, in the nonwoven fabric, if the recovery energy (WC') of the uppermost convex portion 15 is large, the resilience when pressed by the skin of the hand, i.e., cushioning, becomes appropriate, resulting in an excellent texture. From this viewpoint, the recovery energy (WC') of the uppermost convex portion 15 is set to 1.7 gfcm / cm 2 More than 2gfcm / cm is preferable. 2 More preferably, from the viewpoint of suppressing the repulsive force and maintaining a suitable texture, the recovery energy (WC') at the convex portion is 10 gfcm / cm 2 Less than 8gfcm / cm is preferable. 2 It is more preferable that:

[0116] In the case of a nonwoven fabric, when the above-mentioned deformation amount is large, the larger the RC value, the smaller the hysteresis in the elastic stress of compression and recovery, the better the cushioning, and the more appropriate the elasticity. That is, the nonwoven fabric may feel less plastic deformation (sagging) when compressed. From this viewpoint, the RC value is preferably 42% or more, and more preferably 44% or more. Also, the closer the RC value is to 100%, the better the elasticity. From this viewpoint, the RC value is preferably 100% or less, and more preferably 100%.

[0117] (0.5gf / cm 2 (Method of measuring total thickness of nonwoven fabric under load) The nonwoven fabric to be measured was cut into a size of 10 cm x 10 cm to prepare a measurement sample. A laser thickness gauge (Omron Corporation, high-precision displacement sensor ZS-LD80 (product name)) was used to measure the thickness of the measurement sample using a flat plate at 0.5 gf / cm 2 A load (load of 0.05 kPa) is applied to the first surface side, and the thickness is measured in this state. Measurements are taken at three locations, and the average value is regarded as the total thickness of the nonwoven fabric being measured. 2 The "load" refers to a load sufficient to suppress fuzzing on the surface of the nonwoven fabric, and is a light load necessary to properly measure the total thickness between the front and back surfaces of the nonwoven fabric (a light load that is not equivalent to a compressive force that would crush the thickness of the nonwoven fabric). If it is not possible to take out a piece of nonwoven fabric measuring 10 cm x 10 cm, take out as large a piece as possible. In addition, under the above high load (50gf / cm 2 The total thickness under load is measured by the above method with a load of 0.5gf / cm 2 to 50 gf / cm 2 (5kPa) to measure.

[0118] In the nonwoven fabric, the initial state before pressing (0.5gf / cm 2 The larger the total thickness (T0) under load, the larger the deformation amount when pressed, and the softer the feel. 2The thickness (T0) under load is preferably 1 mm or more, and more preferably 4 mm or more. In order to prevent the number of fibers in the protrusion 1 from becoming too small, the initial thickness (0.5 gf / cm 2 The deformation under load (T0) is preferably equal to or less than 12 mm, and more preferably equal to or less than 8 mm.

[0119] For nonwoven fabrics, under high load (50gf / cm 2 The larger the total thickness (TM) under pressure, the less likely it is to be crushed even under high load, and the less plastic deformation (sag) it feels. 2 The thickness (TM) when pressed is preferably 0.35 mm or more, more preferably 0.6 mm or more. There is no particular upper limit, but the basis weight is preferably 100 g / m 2 In the following cases, a smaller deformation is better to prevent the distance between fibers from becoming too wide, and from the viewpoint of providing excellent cushioning and strength, a value of 50 gf / cm is recommended. 2 The thickness (TM) when pressed is preferably 2 mm or less, and more preferably 1 mm or less.

[0120] In nonwoven fabrics, the greater the thickness deformation (T0-TM), the softer the feel of the fabric. From this viewpoint, the thickness deformation (T0-TM) is preferably 0.5 mm or more, more preferably 2.5 mm or more, and even more preferably 3.5 mm or more. There is no particular upper limit to the thickness deformation (T0-TM), but it is preferable that the thickness deformation (T0-TM) is 100 g / m 2 In the following cases, a smaller deformation amount is preferable in order to prevent the distance between the fibers from becoming too wide and to provide excellent cushioning and strength, and therefore, the deformation amount is preferably 10 mm or less, more preferably 7 mm or less, and even more preferably 5 mm or less. The larger the deformation amount when a load is applied, the softer the material feels.

[0121] [6] Texture Based on a sensory evaluation based on a combination of factors such as cushioning, deformation when pressed by hand, and smoothness, the nonwoven fabric of Comparative Example 1 was given a score of 1, and the three-dimensionally shaped nonwoven fabric obtained by peeling off the surface material from Kao Corporation's Merry's tape-type diaper M size (manufactured in Japan in 2019) was given a score of 3, with the higher the score, the better the texture, and the evaluation was performed on a 5-point scale. The evaluation was performed in a blind manner by three male and three female researchers. The obtained values ​​were the average values ​​rounded off to the nearest whole number. In addition, the greater the deformation amount when pressed by hand, the softer it tends to feel. When the deformation amount is large, the greater the compression resilience (RC), the smaller the hysteresis in the elastic stress of compression and recovery, and the better the cushioning tends to feel. Furthermore, when the mean coefficient of friction (MIU) is in the above-mentioned moderate range and the mean deviation value of the surface friction coefficient (MMD) is small, it tends to feel moderately smooth, and even if the surface is uneven, there is no catching, and the variation in the coefficient of friction is small, making it feel smooth.

[0122] The results of the above evaluations are shown in Tables 1 and 2 below. 2 The state of the fiber layer observed during the measurement of "total thickness under load" was as shown in Fig. 22. Fig. 22 shows a cross section in the CD direction at the uppermost convex part 15 of the concave-convex shape of the nonwoven fabric sample.

[0123] [Table 1]

[0124] [Table 2]

[0125] As shown in Tables 1 and 2 and Fig. 22, the nonwoven fabric obtained by the manufacturing method of Comparative Example 2 had too many voids due to excessive elongation of the first fiber layer, and was easily crushed. The nonwoven fabric obtained by the manufacturing method of Comparative Example 1 was thick and had a large amount of deformation, but the voids were small and the fiber density of the uppermost convex parts 15 of the first fiber layer was high, so the compression energy was too high and it felt hard. The nonwoven fabric sample obtained by the manufacturing method of Comparative Example 3 had small voids and was thin, so the amount of deformation was small and it felt hard. In contrast, the nonwoven fabric obtained by the manufacturing method of Example 1 had moderate voids that were not too large as in Comparative Example 2, nor too small as in Comparative Examples 1 and 3. Therefore, at the beginning of deformation under a low load, the voids were crushed, causing the fabric to deform softly, but at high loads, the lower layer contributed to the deformation, making the fabric less susceptible to crushing. Furthermore, although the nonwoven fabric obtained by the manufacturing method of Example 1 had a bulkiness and thickness almost equivalent to those of Comparative Example 1, the nonwoven fabric of Example 1 had an appropriate ratio ({H2 / H1}×100) of the height H2 of the first intermediate convex portion 1A of the vertical ridge portion 1 to the height H1 of the uppermost convex portion 15 and an appropriate ratio ({H3 / H1}×100) of the height H3 of the second intermediate convex portion 5A of the horizontal ridge portion 5 to the height H1 of the uppermost convex portion 15, so that the uppermost convex portion 15 was less likely to collapse in both the MD and CD directions, and thus had an appropriate compression energy and was evaluated as having a texture of "4," which was twice that of Comparative Example 1. Therefore, it was found that the manufacturing method of the nonwoven fabric of the present invention can suitably manufacture a nonwoven fabric having a bulky and thick structure, an appropriate compression energy, and excellent texture. [Explanation of symbols]

[0126] 100 First unfused web 200 Second unfused web 110 Support 111 Convex portion of support 120A First Pushing Member 121 Pushing portion of first pushing member 120B Second pushing member 122 Pushing portion of second pushing member

Claims

1. a first shaping step in which an unfused web made of an aggregate containing fibers is shaped by engaging a support having a convex portion or a concave portion with a first pushing member having a pushing portion that can be engaged with the support; a second shaping step of shaping the shaped unfused web by engaging the support with a second pushing member having a pushing portion that can engage with the support; During or after the second shaping step, a heat treatment step of fiber fusion with a heated fluid, or embossing or fusion, a difference between an angle of an engagement direction of a pushing portion of the first pushing member relative to a machine direction of the support and an angle of an engagement direction of a pushing portion of the second pushing member relative to the machine direction of the support being 60 degrees or more and 90 degrees or less; Method for manufacturing nonwoven fabric.

2. a first shaping step of shaping a first unfused web made of an aggregate containing fibers by engaging a support having a convex portion or a concave portion with a first pushing member having a pushing portion that can be engaged with the support; a second shaping step of laminating a second unfused web on the shaped first unfused web on the support, and shaping the second unfused web from the second unfused web side by engaging the support with a second pushing member having a pushing portion that can engage with the support; During or after the second shaping step, a heat treatment step of fiber fusion with a heated fluid, or embossing or fusion, a difference between an angle of an engagement direction of a pushing portion of the first pushing member relative to a machine direction of the support and an angle of an engagement direction of a pushing portion of the second pushing member relative to the machine direction of the support being 60 degrees or more and 90 degrees or less; Method for manufacturing nonwoven fabric.

3. A method for producing a nonwoven fabric as described in claim 1 or 2, wherein the angle of the meshing direction of the pushing portion of the second pushing member relative to the machine flow direction of the support is larger than the angle of the meshing direction of the pushing portion of the first pushing member relative to the machine flow direction of the support.

4. 4. A method for producing a nonwoven fabric as described in claim 3, wherein the angle of the meshing direction of the pushing portion of the first pushing member relative to the machine flow direction of the support is 0 degrees or more and 30 degrees or less, and the angle of the meshing direction of the pushing portion of the second pushing member relative to the machine flow direction of the support is 60 degrees or more and 90 degrees or less.

5. A method for producing a nonwoven fabric as described in claim 1 or 2, wherein the angle of the meshing direction of the pushing portion of the second pushing member relative to the machine flow direction of the support is smaller than the angle of the meshing direction of the pushing portion of the first pushing member relative to the machine flow direction of the support.

6. 6. A method for producing a nonwoven fabric as described in claim 5, wherein the angle of the meshing direction of the pushing portion of the first pushing member relative to the machine flow direction of the support is 60 degrees or more and 90 degrees or less, and the angle of the meshing direction of the pushing portion of the second pushing member relative to the machine flow direction of the support is 0 degrees or more and 30 degrees or less.

7. A method for producing a nonwoven fabric as described in claim 1 or 2, wherein the ratio (former / latter) of the amount of engagement of the pushing portion of the first pushing member with the support to the amount of engagement of the pushing portion of the second pushing member with the support is 1.2 times or more.

8. A method for manufacturing a nonwoven fabric described in any one of claims 1 or 2, wherein the first pushing member or the second pushing member has an interlocking direction of the support relative to the machine direction of 60 degrees or more and 90 degrees or less, and the uniform gap in the machine direction formed between the convex portion and the pushing portion when interlocked is 0.5 mm or more and 1.5 mm or less.

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