Nonwoven fabric, various products using the same and nonwoven fabric manufacturing method

Abstract

To provide a nonwoven fabric excellent in liquid diffusion, SAP support, and water-permeable properties.SOLUTION: A nonwoven fabric 10 is constituted of fibers and has prescribed number of intersections of fibers adhered to each other, a first area 1A having a prescribed thickness, and a second area 2A that has the number of intersections of fibers adhered to each other, which is fewer than the first area 1A, and thickness larger than the first area 1A. The second area 2A is located between a plurality of the first areas 1A located along a prescribed direction. Width of the first area 1A is 0.5 to 20.0 mm. Interval of the first areas in the prescribed direction is 2 to 50.0 mm.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a nonwoven fabric, various products using the same, and a method for producing the nonwoven fabric. [Background technology]

[0002] In recent years, from the viewpoint of environmental consideration, there has been a demand for diapers that conserve resources and are easy to recycle. With the increase in the senior population, there is a demand for thinner diapers for adults, for reasons such as easier movement, making the diaper less noticeable under clothing, and making it easier to achieve a smart appearance.

[0003] Super absorbent polymers (hereinafter sometimes referred to as "SAP") are known as absorbents for diapers. SAP is supported on a support (hereinafter sometimes referred to as "SAP support"). The SAP support is required to easily support a large amount of SAP, to be unlikely to inhibit water passage through the SAP, and to have suitable liquid diffusibility to prevent inhibition of water absorption (gel blocking) that may occur due to localized water absorption of SAP.

[0004] As a nonwoven fabric suitable for an SAP support, a nonwoven fabric for sanitary materials has been disclosed that has a length / width ratio (length / width) of the mean coefficient of friction variation (MMD) measured by the KES method of 0.5 or more and a fluff grade of 4 or less measured by the Martindale method (see Patent Document 1). The objective of Patent Document 1 is to provide a nonwoven fabric for sanitary materials that is excellent in water retention, SAP support, and water permeability. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] International Publication No. 2022 / 239838 Summary of the Invention [Problem to be solved by the invention]

[0006] In order to further improve the performance of SAP sheets, further improvements in liquid diffusibility, SAP supportability, and water permeability are required.

[0007] An object of the present invention is to provide a nonwoven fabric having excellent liquid diffusibility, SAP supportability, and water permeability. Another object of the present invention is to provide various products using the nonwoven fabric, and a method for producing the nonwoven fabric. [Means for solving the problem]

[0008] Examples of embodiments of the present disclosure are as follows. [1] A nonwoven fabric composed of fibers, A first region having a predetermined number of intersections where the fibers are bonded to each other and having a predetermined thickness; A second region having a smaller number of intersections between the fibers than the first region and a larger thickness than the first region, the second region is present between a plurality of the first regions that are present along a predetermined direction, The width of the first region in the predetermined direction is 0.5 to 20.0 mm, The interval between the first regions in the predetermined direction is 2 to 50.0 mm. Nonwoven fabric. [2] 2. The nonwoven fabric according to item 1, wherein the predetermined direction is a width direction of the nonwoven fabric. [3] 3. The nonwoven fabric according to item 1 or 2, wherein the first region and the second region are provided on at least one of the front surface and the back surface of the nonwoven fabric. [4] The first region where a large number of the intersections are bonded and the second region where a large number of the intersections are not bonded are alternately present in the width direction, The thickness of the first region is smaller than the thickness of the second region, The width of the first region is 0.5 to 20 mm, 4. The nonwoven fabric according to any one of items 1 to 3, wherein the interval between the first regions is 2 to 50 mm. [5] 5. The nonwoven fabric according to any one of items 1 to 4, wherein the difference in thickness between the first region and the second region is 0.20 mm or more. [6] When a plurality of arbitrarily selected intersections of the nonwoven fabric are observed, In the first region, more than half of the intersections are observed to be bonded, 6. The nonwoven fabric according to any one of items 1 to 5, wherein half or more of the intersections observed in the second region are not bonded. [7] 7. The nonwoven fabric according to any one of items 1 to 6, which is formed using long fibers. [8] 8. An SAP support comprising the nonwoven fabric according to any one of items 1 to 7. [9] Item 9. A SAP sheet comprising the SAP support and the SAP according to item 8.

[10] 10. An absorbent article comprising the SAP sheet according to item 9.

[11] A sanitary material comprising the nonwoven fabric according to any one of items 1 to 7.

[12] A method for producing a nonwoven fabric comprising the steps of: fusing the web of fibers at predetermined intervals along a predetermined direction; A method for manufacturing nonwoven fabric.

[13] Item 13. The method for producing a nonwoven fabric according to item 12, wherein the web is fused by blowing hot air onto the web from hot air blowing ports arranged intermittently along the predetermined direction.

[14] depositing the fibers on a conveyor to form the web; and forming a first region on the web by blowing hot air onto the web from hot air outlets arranged intermittently in the predetermined direction while the web is being transported by the conveyor; The width of the first region in the predetermined direction is 0.5 to 20.0 mm, Item 14. The method for producing a nonwoven fabric according to item 13, wherein the interval between the first regions in the predetermined direction is 2 to 50.0 mm.

[15] The width of the hot air outlet in a predetermined direction is 0.5 to 20 mm, Item 15. The method for producing a nonwoven fabric according to item 13 or 14, wherein the interval between the hot air outlets in a predetermined direction is 2 to 50 mm.

[16] 16. The method for producing a nonwoven fabric according to any one of items 13 to 15, wherein the hot air has a wind speed of 5 m / sec or more. Effect of the Invention

[0009] According to the present invention, it is possible to provide a nonwoven fabric having excellent liquid diffusibility, SAP supportability, and water permeability. Furthermore, according to the present invention, it is possible to provide various products using the nonwoven fabric, and a method for producing the nonwoven fabric. [Brief description of the drawings]

[0010] [Figure 1] FIG. 2 is a schematic diagram showing an example of the configuration of the nonwoven fabric of the present embodiment. [Diagram 2] FIG. 4 is a plan view showing a configuration example of a hot air outlet. [Diagram 3] FIG. 4 is a plan view showing a configuration example of a hot air outlet. [Figure 4] FIG. 4 is a plan view showing a configuration example of a hot air outlet. [Diagram 5] FIG. 4 is a plan view showing a configuration example of a hot air outlet. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In this specification, for stepwise numerical ranges, the upper or lower limit of a certain numerical range can be replaced with the upper or lower limit of another stepwise numerical range, and can also be replaced with the corresponding value in the examples. In this specification, the term "step" does not mean only an independent step, and therefore, even if it cannot be clearly distinguished from other steps, it is included in the term "step" as long as the function of the step is achieved. In addition, in the contents shown in the drawings, the scale, shape, and length may be exaggerated for further clarity. In this specification, various measurements are performed based on the methods described in the examples, unless otherwise specified.

[0012] In this specification, the term "along a specific direction" means not only a state in which the direction completely coincides with the target direction, but also a state in which the direction is roughly the same as the target direction, i.e., a state in which the direction has a certain degree of inclination. Thus, for example, the term "direction along the longitudinal direction of the nonwoven fabric" includes not only a direction in which the direction completely coincides with the longitudinal direction, but also a direction in which the direction has a certain degree of inclination with respect to the longitudinal direction. The "certain degree of inclination" here is acceptable within the scope of the present invention. The material constituting the nonwoven fabric may be used alone or in combination of two or more kinds.

[0013] [Embodiment 1] In this embodiment, A nonwoven fabric composed of fibers, A first region having a predetermined number of intersections where fibers are bonded to each other and having a predetermined thickness; A second region having a smaller number of intersections between fibers than the first region and a greater thickness than the first region, the second region is present between a plurality of first regions that are present along a predetermined direction, The width of the first region in the predetermined direction is 0.5 to 20.0 mm, The interval of the first region in the predetermined direction is 2 to 50.0 mm. It is a nonwoven fabric. According to the present embodiment, it is possible to provide a nonwoven fabric having excellent liquid diffusibility, SAP supportability, and water permeability. Hereinafter, the present embodiment will be described with reference to the drawings.

[0014] <Nonwoven fabric> FIG. 1 is a schematic diagram showing an example of the configuration of the front surface and / or back surface of a nonwoven fabric 10 of this embodiment. 1 may be used on either the front or back surface of the nonwoven fabric 10, or may be used on both the front and back surfaces. The X direction is, for example, a direction along the longitudinal direction of the nonwoven fabric 10, and the Y direction is, for example, a direction along the short side direction (width direction) of the nonwoven fabric 10. Here, the X direction and the Y direction are perpendicular to each other.

[0015] The first region 1A is an adhesive portion 1 in one embodiment, and the second region 2A is a non-adhesive portion 2 in one embodiment. That is, the nonwoven fabric 10 has, on at least one of the front and back surfaces, A bonding portion 1 (first region 1A) extending in the X direction and having a large number of fiber intersections bonded together; The bonded portions 1 extend in the X direction, and non-bonded portions 2 (second regions 2A) where many of the fiber intersections are not bonded are alternately present in the Y direction. A plurality of bonded portions 1 exist along the Y direction, and the non-bonded portions 2 exist between the plurality of bonded portions 1.

[0016] The minimum unit of the nonwoven fabric of this embodiment is two bonded portions 1 and one non-bonded portion 2 disposed between the bonded portions 1 . 1 shows seven bonded parts 1 and six non-bonded parts 2, but the number of repetitions is not limited. The configurations of the repeated bonded parts 1 may be the same or different from each other, and the configurations of the non-bonded parts 2 that may be repeated may be the same or different from each other.

[0017] A cross section of the nonwoven fabric 10 is cut out, for example, with a razor. The cut out cross section is observed at a magnification of 20 times using a microscope, for example, a VHX-6000 manufactured by KEYENCE. At this time, the boundary or the vicinity thereof between a relatively thin portion (hereinafter sometimes referred to as a "concave portion") and a relatively thick portion (hereinafter sometimes referred to as a "protruding portion") is confirmed.

[0018] The above-mentioned boundary or its vicinity is observed from the surface of the nonwoven fabric 10 at a magnification of 100 times using a VE-8800 manufactured by KEYENCE, and a predetermined number of intersections between fibers (for example, 10 points) are arbitrarily selected. When a state in which fibers are melted and bonded to each other is observed, it is judged that "adhesion at the intersections is observed," and when a state in which fibers are not melted and bonded to each other is observed, it is judged that "adhesion at the intersections is not observed." If adhesion is observed at more than half of the intersections (five or more when ten intersections are selected), it can be defined as "adhesive portion 1 (first region 1A)," and if not, it can be defined as "non-adhesive portion 2 (second region 2A)," and thus each region of the adhesive portion 1 and the non-adhesive portion 2 can be determined. That is, when observing a number of arbitrarily selected intersections of the nonwoven fabric 10, In the adhesive portion 1 (first region 1A), more than half of the intersections were observed to be adhesive. It is preferable that more than half of the intersections are not bonded in the non-bonded portion 2 (second region 2A). It is also preferable that no bonded intersections are observed in the non-bonded portion 2 (second region 2A).

[0019] Due to the presence of the non-adhesive portions 2, when tension is applied in the longitudinal direction of the nonwoven fabric in each process (e.g., a diaper manufacturing process, a SAP sheet manufacturing process, etc.) when various products are produced using the nonwoven fabric 10, the non-adhesive portions 2 tend to shrink, and therefore the fibers in the non-adhesive portions 2 tend to stand up. This makes it easier to obtain a low bulk density in the non-adhesive portions 2. The low bulk density of the non-adhesive portions 2 makes it easier for SAP to be supported on the nonwoven fabric 10, and also makes it easier for water permeability to be improved.

[0020] The presence of adhesive parts 1 enables nonwoven fabric 10 to easily maintain the shape of a sheet. The width of the bonded part 1 in the Y direction is 0.5 to 20.0 mm. When the width of the bonded part 1 is 0.5 mm or more, the ratio of the bonded intersections in the entire nonwoven fabric is easily ensured, so that the nonwoven fabric can be easily transported without problems during production. When the width of the bonded part 1 is 20.0 mm or less, the ratio of the bonded intersections in the entire nonwoven fabric is easily prevented from excessively increasing, so that the liquid diffusibility, water permeability, and texture are easily improved. From the same viewpoint as above, the width of the bonded part 1 is preferably 0.75 to 10.0 mm, more preferably 1.0 to 5.0 mm. In this specification, the term "web" means an assembly of fibers before they are bonded to each other.

[0021] The interval between the bonded parts 1 in the Y direction is 2.0 to 50.0 mm. When the interval between the bonded parts 1 is 2.0 mm or more, the bulkiness of the nonwoven fabric 10 is easily obtained, and therefore the SAP support is easily improved. When the interval between the bonded parts 1 is 50.0 mm or less, the ratio of bonded intersections to the entire nonwoven fabric is easily ensured, and the nonwoven fabric can be easily transported without problems. From the same viewpoint as above, the interval between the bonded parts 1 is preferably 5.0 to 40.0 mm, more preferably 10.0 to 30.0 mm. The intervals between the repeated bonded parts 1 may be the same or different from each other.

[0022] In order to enhance liquid diffusibility, the nonwoven fabric 10 has a smaller thickness in the bonded portion 1 than in the non-bonded portion 2. When no load is applied to the nonwoven fabric 10 in the thickness direction, the difference in thickness between the bonded portion 1 and the non-bonded portion 2 is preferably 0.20 mm or more, and more preferably 0.40 mm or more. The upper limit of the thickness of the non-bonded portion 2 may be about 2.50 mm.

[0023] As described above, the nonwoven fabric 10 is A first region 1A having a predetermined number of intersections where fibers are bonded to each other and having a predetermined thickness; The second region 2A has a smaller number of intersections where fibers are bonded to each other than in the first region 1A and is thicker than the first region 1A.

[0024] The nonwoven fabric 10 may be made of either long or short fibers. However, from the viewpoints of ensuring strength, ensuring productivity, reducing irritation to the skin, etc., it is preferable that the nonwoven fabric 10 contains long fibers, and is particularly preferable to be a spunbonded nonwoven fabric. Here, "spunbonded nonwoven fabric" refers to a nonwoven fabric made of fibers formed by extruding resin filaments from multiple fine openings in a spinneret and rapidly thinning the extruded resin filaments.

[0025] In this specification, "long fiber" means a fiber having a fiber length of 50 mm or more. From the viewpoint of preventing contamination during the manufacturing process of various products (e.g., the manufacturing process of diapers) due to fiber shedding, the longer the fiber length, the more preferable. The nonwoven fabric 10 is preferably composed of fibers having an average fiber length of 50 mm or more, more preferably 80 mm or more, and even more preferably 100 mm or more.

[0026] The nonwoven fabric 10 is preferably constructed using fibers made of a thermoplastic resin. Examples of the thermoplastic resin include: Polyolefin resins such as polyethylene, polypropylene, and copolymer polypropylene; Polyester-based resins such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, and copolymer polyesters; Polyamide resins such as nylon-6, nylon-66, and copolymer nylons; and Biodegradable resins such as polylactic acid, polybutylene succinate, and polyethylene succinate; From the viewpoint of the feel of the nonwoven fabric, and also from the viewpoints of versatility, ease of collection, and recycling since many applications of nonwoven fabrics are disposable materials, polyolefin resins are preferred as the thermoplastic resin.

[0027] Examples of the form of the fibers constituting the nonwoven fabric 10 include fibers with a circular cross section, fibers with an irregular cross section, hollow fibers, and composite fibers composed of two or more types of thermoplastic resins. From the viewpoint of providing appropriate voids in the nonwoven fabric and improving the SAP carrying amount, it is preferable that the fibers constituting the nonwoven fabric are crimped. The means for crimping the fibers include: A method of using fibers with irregular cross sections and unevenly cooling them during spinning and cooling; and A method using bicomponent fibers composed of two or more types of thermoplastic resins; The use of composite fibers such as "side-by-side (S / S)" fibers and "eccentric sheath-core (eS / C)" fibers makes it easier to produce crimp.

[0028] When the fibers constituting the nonwoven fabric are of eccentric sheath-core type (eS / C), the core may be completely covered by the sheath, or a part of the core may be exposed on the fiber surface. When a part of the core is exposed on the fiber surface, the ratio of the area of ​​the exposed part of the core to the area of ​​the fiber surface (area of ​​the exposed part of the core / area of ​​the fiber surface) is preferably more than 0% and not more than 50%, more preferably more than 0% and not more than 30%. If this ratio is 50% or less, adverse effects are unlikely to occur when the nonwoven fabric is joined, and therefore sufficient strength is easily achieved.

[0029] When the fibers constituting the nonwoven fabric are composite fibers composed of two or more types of thermoplastic resins, any of the above thermoplastic resins may be combined. In this case, from the viewpoint of suitable bonding between the fibers, a combination of thermoplastic resins having different melting points is preferred. When the fibers constituting the nonwoven fabric are composite fibers composed of two types of thermoplastic resins (including the case where there are substantially two types), the mass ratio of the resin with the higher melting point in the fibers (mass of the resin with the higher melting point / total mass of the resins constituting the fibers) is preferably 20 to 80 mass%, more preferably 30 to 80 mass%, and even more preferably 50 to 70 mass%. Here, "when there are substantially two types" means a combination in which the mass ratio of the thermoplastic resin other than the two specified types in the fibers is very small (for example, 1 mass% or less) even when the fibers constituting the nonwoven fabric are composite fibers composed of three or more types of thermoplastic resins.

[0030] When the fibers constituting the nonwoven fabric are composite fibers composed of three or more types of thermoplastic resins, the mass ratio of the resin with the highest melting point in the fibers (mass of the resin with the highest melting point / total mass of the resins constituting the fibers) is preferably 20 to 80 mass%, more preferably 30 to 80 mass%, and even more preferably 50 to 70 mass%. This mass ratio may also be calculated excluding resins that make up a small amount (for example, 1 mass% or less) of the mass ratio in the fibers, as above.

[0031] When the fibers constituting the nonwoven fabric are composite fibers composed of two or more types of thermoplastic resins, from the viewpoint of the texture of the nonwoven fabric, a combination of two or more types of polyolefin-based resins, or a combination of a polyolefin-based resin and a polyester-based resin is preferred. When two or more kinds of polyolefin resins are combined, examples of the polyolefin resins used include polyethylene, polypropylene, and copolymers of these monomers with other α-olefins, etc. Examples of the other α-olefins include olefins having 3 to 10 carbon atoms, specifically propylene, 1-butene, 1-pentene, 1-hexane, 4-methyl-1-pentene, 1-octene, etc.

[0032] The olefin resin may be bioethanol or bioisopropanol, or may be a plant-derived resin produced from bionaphtha derived from vegetable oil. When a polyolefin resin and a polyester resin are combined, the polyolefin resin may be the above resin, and the polyester resin may be a polyethylene terephthalate single component or a copolymer containing isophthalic acid or the like. The polyethylene terephthalate may be modified by blending or the like, or may be provided with additives or the like. As a combination of thermoplastic resins, a combination of polypropylene and polyethylene is preferred from the viewpoints of high strength and resistance to breakage, excellent processing characteristics during the production of sanitary materials, good texture, and excellent recyclability. From the same viewpoint as above, when the composite fiber is an eccentric core-sheath core type, it is preferable to use polypropylene as the resin of the core and / or polyethylene as the resin of the sheath.

[0033] When polypropylene is used as the fiber constituting the nonwoven fabric, any of polypropylene synthesized by a general Ziegler-Natta catalyst, polypropylene synthesized by a single-site active catalyst represented by metallocene, and ethylene random copolymer polypropylene may be used alone or in combination of two or more. From the viewpoint of texture, strength, and dimensional stability, it is preferable to use homopolypropylene as the main component (for example, 50 mass% or more of the total resin).

[0034] When polypropylene is used as a fiber constituting a nonwoven fabric, from the viewpoint of spinnability during fiber production and / or fiber strength, the melt flow rate (hereinafter sometimes abbreviated as "MFR") of the polypropylene is preferably 20 g / 10 min or more, more preferably more than 30 g / 10 min, even more preferably more than 40 g / 10 min, and most preferably more than 53 g / 10 min. The MFR of polypropylene is preferably 250 g / 10 min or less, more preferably 120 g / 10 min or less, and even more preferably 60 g / 10 min or less. The MFR of polypropylene is measured in accordance with the combination of "test temperature 230 ° C." and "test load 2.16 kg" in Table 1 in Appendix A of JIS-K7210 "Test method for melt mass flow rate (MFR) and melt volume flow rate (MVR) of plastics-thermoplastics".

[0035] When polyethylene is used as the fiber constituting the nonwoven fabric, either polyethylene synthesized by a general Ziegler-Natta catalyst or polyethylene synthesized by a single-site active catalyst such as metallocene may be used. The polyethylene is preferably high-density polyethylene or linear low-density polyethylene, and its density is preferably 0.92 to 0.97 g / cm. 3 and more preferably 0.925 to 0.96 g / cm 3 The polyethylene may be used alone or in combination of two or more kinds. From the viewpoint of improving the adhesion at the intersections between the fibers, it is preferable to use a mixture of linear polyethylene in a proportion of 0.5 to 80 mass % relative to the high density polyethylene.

[0036] When polyethylene is used as the fiber constituting the nonwoven fabric, from the viewpoint of spinnability during fiber production, the melt index (hereinafter sometimes abbreviated as "MI") of the polyethylene is preferably 10 g / 10 min or more, more preferably more than 15 g / 10 min. The MI of the polyethylene is preferably 100 g / 10 min or less, more preferably 60 g / 10 min or less, and even more preferably 40 g / 10 min or less. The MI of the polyethylene is measured in accordance with the combination of "test temperature 190°C" and "test load 2.16 kg" in Table 1 in Appendix A of JIS-K7210 "Test method for melt mass-flow rate (MFR) and melt volume-flow rate (MVR) of plastics-thermoplastics".

[0037] When a polyester resin is used as the fiber constituting the nonwoven fabric, the solution viscosity ηsp / c of ​​the polyester resin is preferably 0.2 or more, more preferably 0.6 or more. The solution viscosity ηsp / c is preferably 0.9 or less, more preferably 0.8 or less. The solution viscosity ηsp / c is measured using a viscosity tube in a thermostatic water bath at a concentration of 0.01 g / mL and a temperature of 35° C. using o-chlorophenol (OCP) as a solvent.

[0038] The nonwoven fabric may contain a water permeable agent. From the viewpoints of safety to the human body and safety during the manufacturing process, examples of the water permeable agent include higher alcohols, higher fatty acids, nonionic surfactants with ethylene oxide added thereto (such as alkylphenols), alkyl phosphate salts, and anionic surfactants (such as alkyl sulfate salts), and these may be used alone or in combination of two or more kinds.

[0039] When the nonwoven fabric contains a water-permeable agent, the content of the water-permeable agent is preferably 0.10 to 2.00% by mass, more preferably 0.15 to 1.50% by mass, based on the mass of the nonwoven fabric. By setting the content of the water-permeable agent to 0.10% by mass or more, it is easy to impart sufficient water permeability to the nonwoven fabric. By setting the content of the water-permeable agent to 1.50% by mass or less, it is easy to realize a nonwoven fabric that is highly safe to the skin (for example, a nonwoven fabric that is unlikely to cause skin rashes and eczema).

[0040] The nonwoven fabric may have different configurations and / or properties, for example, different water permeability, between one side and the other side. By adding a highly hydrophilic water permeable agent to one side and / or increasing the content of the water permeable agent, the water permeability can be increased, and by adding a less hydrophilic water permeable agent to the other side and / or decreasing the content of the water permeable agent, the liquid diffusibility can be increased.

[0041] The nonwoven fabric may have a single layer structure or a laminated structure of two or more layers. When the nonwoven fabric has a laminated structure, all layers may be the nonwoven fabric of the present disclosure, or only some layers may be the nonwoven fabric of the present disclosure. An example of a case where only some layers are the nonwoven fabric of the present disclosure is a laminated structure of the nonwoven fabric of the present disclosure and a normal spunbonded nonwoven fabric.

[0042] <Production method of nonwoven fabric> A further aspect of this embodiment is a method for producing a nonwoven fabric 10 composed of fibers. The method includes a step of fusing a fibrous web at predetermined intervals along a predetermined direction by blowing hot air onto the web from hot air outlets that are intermittently arranged along the predetermined direction, thereby fusing the web.

[0043] The method for producing a nonwoven fabric preferably includes the following steps 1 and 2. That is, the nonwoven fabric is, for example, depositing fibers on a conveyor to form a web (step 1); and It is preferable that the web be manufactured by a method including a step (step 2) of forming adhesive portion 1 (first region 1A) on the web by blowing hot air onto the web from hot air outlets arranged intermittently in a predetermined direction while the web is transported by the conveyor.

[0044] The fibers constituting the nonwoven fabric are produced, for example, by a step (step 0) of producing fibers by discharging a molten thermoplastic resin from a spinneret. Therefore, the method for producing the nonwoven fabric may include step 0.

[0045] (Process 0) In this process, a thermoplastic resin is extruded from an extruder, and resin filaments are discharged from a spinneret having a large number of spinning holes. When a nonwoven fabric is produced using a composite fiber in which two or more types of thermoplastic resins are combined, for example, different thermoplastic resins are extruded from two or more different extruders, and the two or more types of thermoplastic resins are discharged from the spinneret in a composite state as resin filaments.

[0046] The discharged resin filaments are exposed to air controlled at a temperature of preferably 3 to 28° C. to promote cooling, and then fibers are produced. In the process of producing the fibers, the resin filaments may be pulled by a pulling device while being cooled.

[0047] In the method for producing a nonwoven fabric, the above step 0 is not essential. In the method for producing a nonwoven fabric, when the above step 0 is omitted, fibers produced by any step that may include the above step 0 can be used.

[0048] (Process 1) In this process, the fibers are deposited on a conveyor to form a web. Another web may be laminated on the web deposited on the conveyor, or a web may be joined once and then laminated on another web online or offline. When laminating, each layer may be formed of webs with different fiber diameters, and of course webs made of fibers with different configurations (e.g., fibers with circular cross sections, fibers with irregular cross sections, crimped fibers, hollow fibers, etc.) may be laminated.

[0049] (Process 2) In this step, hot air is blown onto the web from hot air outlets arranged intermittently in a predetermined direction (for example, the y direction in Figs. 2 to 5) while the web is being transported on a conveyor, thereby forming bonded parts 1 (first regions 1A) on the web. The predetermined direction here corresponds to the direction along the short side direction (width direction) of the nonwoven fabric 10. As the heating method in step 2, a hot air penetration type (a method in which hot air is allowed to penetrate the heating target and heat it) is preferred, since this makes it easier to obtain more fiber bonding points at the intersections between the fibers, and as a result, makes it easier to increase the breaking strength of the nonwoven fabric.

[0050] The hot air outlet is composed of one or more openings arranged at a predetermined interval in the machine direction (MD). Hot air blown out from the hot air outlet can form a bonded part (first region) on the web. The shape of the opening constituting the hot air outlet can be a square, a rectangle, a circle, an ellipse, etc. For example, hot air can be blown onto the web while the web is being transported in a predetermined direction (for example, the x direction in Figs. 2 to 5).

[0051] The intervals between the hot air outlets may be equal or different. By appropriately adjusting the intervals between the hot air outlets, the intervals between the bonded portions (first regions) in the nonwoven fabric along a predetermined direction can be appropriately adjusted.

[0052] FIG. 2 is a plan view showing an example of the configuration of the hot air outlet 3. As shown in FIG. The hot air outlet 3-2 is composed of one rectangular opening 4, and the hot air outlets 3-2 are arranged at equal intervals in a predetermined direction (y direction). By using such hot air outlet 3-2, it is possible to form adhesive parts (first regions) in the nonwoven fabric that are rectangular and arranged at equal intervals in the predetermined direction.

[0053] FIG. 3 is a plan view showing another example of the configuration of the hot air outlet 3. As shown in FIG. The hot air outlet 3-3 is composed of a plurality of rectangular openings 4, and the hot air outlets 3 are arranged at equal intervals in a predetermined direction (y direction). The hot air outlet 3-3 shown in Fig. 3 differs from the hot air outlet 3-2 shown in Fig. 2 in that it is composed of openings 4 arranged discontinuously along the x direction.

[0054] FIG. 4 is a plan view showing another example of the configuration of the hot air outlet 3. As shown in FIG. The hot air outlet 3-4 is composed of a collection of small rectangular openings 4, and the hot air outlets 3-4 are arranged at equal intervals in a predetermined direction (y direction). The hot air outlet 3-4 shown in Fig. 4 differs from the hot air outlet 3-3 shown in Fig. 3 in that the hot air outlet 3-4 is composed of a large number of small openings 4.

[0055] FIG. 5 is a plan view showing another example of the configuration of the hot air outlet 3. As shown in FIG. The hot air outlet 3-5 is composed of one or more rectangular openings 4, and the hot air outlets 3-5 are arranged at equal intervals in a predetermined direction (y direction). The hot air outlet 3-5 shown in Fig. 5 differs from the hot air outlet 3-3 shown in Fig. 3 in that the openings 4 are arranged in a staggered pattern along the predetermined direction (y direction).

[0056] 2 to 5 may be combined. For example, the present embodiment also includes a configuration in which hot air outlets 3-2 to 3-5 having different configurations are randomly arranged along the y direction.

[0057] The width (W) of the hot air outlet 3 is preferably 0.5 to 20.0 mm or less, and more preferably 1 to 5 mm. When the width (W) of the hot air outlet 3 is 0.5 mm or more, it is easy to ensure a sufficient ratio of bonded intersections in the entire nonwoven fabric, so that the web can be easily transported without problems. When the width (W) of the hot air outlet 3 is 20.0 mm or less, it is easy to prevent an excessive increase in the ratio of bonded intersections in the entire nonwoven fabric, so that the liquid diffusibility, water permeability, and texture are easily improved. The width (W) of the hot air outlet 3 refers to the maximum width of the hot air outlet 3 in a predetermined direction (for example, the y direction in Figs. 2 to 5).

[0058] The distance (D) between the hot air outlets 3 is preferably 2 to 50.0 mm, and more preferably 10 to 30.0 mm. When the distance (D) is 2 mm or more, the resulting nonwoven fabric is likely to have sufficient bulk, making it easier to obtain sufficient SAP support. When the distance (D) is 50.0 mm or less, the resulting nonwoven fabric is likely to have sufficient strength, making it less likely to break during transportation. The distance (D) is the distance between the center of the width of a certain hot air outlet (center line L1) and the center of the width of another hot air outlet adjacent to that hot air outlet (center line L2).

[0059] The hot air speed is preferably 5.0 m / s or more, more preferably 10 m / s or more, even more preferably 20 m / s or more, and is preferably 50 m / s or less, more preferably 40 m / s or less, even more preferably 30 m / s or less. When the hot air speed is 5.0 m / s or more, the fibers are easily bonded to each other, and the nonwoven fabric can be easily transported without problems. When the hot air speed is 50 m / s or less, the fibers are easily bonded to each other without impairing the texture.

[0060] The temperature of the hot air is appropriately selected depending on the type of resin to be bonded. When the resin to be bonded is polyethylene, the temperature of the hot air is preferably 135 to 175°C, more preferably 140 to 170°C. When the temperature of the hot air is 135°C or higher, the fibers can be bonded sufficiently easily, and the nonwoven fabric can be easily transported without problems. When the temperature of the hot air is 175°C or lower, the fibers can be bonded easily without impairing the texture.

[0061] The above step 2 may include a step of applying a water permeable agent to the nonwoven fabric after the hot air has been blown onto it. The method of applying the water permeable agent can be a coating method (gravure coater, kiss coater), a spraying method, etc., and if necessary, a pretreatment such as a corona discharge treatment, an atmospheric pressure plasma discharge treatment, etc. As a drying method after application, a method utilizing convection heat transfer, conductive heat transfer, radiation heat transfer, etc. can be used, and drying by hot air, drying by infrared rays, drying by thermal contact, etc. can also be used.

[0062] The water-permeable agent may be diluted with a solvent such as water to obtain an aqueous water-permeable agent solution, which is then applied to the nonwoven fabric. In addition, when insufficient drying is expected to occur in the drying process due to the increased speed of the equipment, it is preferable to reduce the amount of the aqueous water-permeable agent applied. In any of the above application methods, the amount of application to the nonwoven fabric (mass of the water-permeable agent applied to the nonwoven fabric / mass of the nonwoven fabric: mass%) is preferably 1.0 to 65 mass%, more preferably 3.0 to 60 mass%, and even more preferably 5.0 to 50 mass%. When the application amount (mass%) is 1.0 mass% or more, the water-permeable agent can be easily applied uniformly to the nonwoven fabric. When the application amount (mass%) is 65 mass% or less, the cost required for drying the nonwoven fabric to which the water-permeable agent has been applied (drying time, drying equipment cost, etc.) can be easily reduced, and insufficient drying can be easily suppressed.

[0063] When applying the water-permeable agent to the nonwoven fabric, it is preferable to apply it by a kiss coater method using a stainless steel applicator roll from the viewpoint of ease of managing the application equipment. In this case, the water-permeable agent is continuously supplied to a bath, and the water-permeable agent can be applied by contacting the nonwoven fabric with a rotating roller in the bath. The amount of water-permeable agent applied can be easily controlled by adjusting the number of revolutions per minute of the kiss roll.

[0064] When applying the water-permeable agent to a nonwoven fabric, spraying is also preferred because it is easy to respond to high-speed application, it is easy to apply efficiently, and it is easy to control the thickness of the nonwoven fabric. Examples of spraying methods include an air spray method in which the water-permeable agent is made into a fine mist by compressed air and then sprayed, and a rotor dampening method in which the water-permeable agent is made into a mist by using the centrifugal force of a rotor rotation and then sprayed. When applying the water-permeable agent by spraying, it may be sprayed on only one side or both sides of the nonwoven fabric.

[0065] Regarding drying after the application of the water-permeable agent, examples of the drying method include methods using convection heat transfer, conductive heat transfer, radiation heat transfer, etc., and also include hot air circulation type, hot air penetration type, infrared heater type, etc. Furthermore, examples of the drying method include a method of blowing hot air on both sides of the nonwoven fabric, a method of introducing the nonwoven fabric into heated gas, etc.

[0066] <SAP support> A further aspect of this embodiment is the SAP support. The SAP support comprises a nonwoven fabric of the present disclosure and may optionally further comprise other nonwoven fabrics.

[0067] <SAP sheet> A further aspect of this embodiment is a SAP sheet. The SAP sheet includes the SAP support of the present disclosure and SAP. SAP refers to a polymeric compound capable of absorbing and retaining water several hundred to approximately one thousand times its own weight. Examples of SAP include polyvinyl alcohol, polyethylene glycol, polyacrylonitrile, and polyacrylic acid-based polymeric compounds, and from the viewpoint of high water absorption, polyacrylic acid-based polymeric compounds are preferred, and sodium polyacrylate is more preferred. The SAP sheet is constructed by supporting SAP on the SAP support.

[0068] <Absorbent articles> A further aspect of this embodiment is an absorbent article. The absorbent article includes the SAP sheet of the present disclosure as an absorbent body. Examples of the absorbent article include diapers, sanitary napkins, incontinence pads, pet sheets, etc. In the absorbent article, the components other than the absorbent body may be any known components.

[0069] <Hygiene materials> A further aspect of this embodiment is a sanitary material. The sanitary material includes the nonwoven fabric of the present disclosure. Examples of the sanitary material include diapers, masks, hand warmers, tape bases, patch bases, first aid bandage bases, packaging materials, wipe products, medical gowns, bandages, clothing, skin care sheets, etc. When the sanitary material is a diaper, the nonwoven fabric of the present disclosure can be applied to a top sheet, a second sheet, a back sheet, a SAP sheet, etc. EXAMPLES

[0070] The present embodiment will be described in more detail with reference to examples and comparative examples. However, the present invention is not limited to the following examples. Unless otherwise specified, various measurements in the present examples were performed at room temperature (about 25° C.).

[0071] [Various measurements] <Weight (g / m 2 )〉 In accordance with JIS-L1913, five samples of 20 cm in the longitudinal direction and 5 cm in the transverse direction were taken so that the positions of the samples were almost evenly spaced across the width of the nonwoven fabric. The mass of each sample was then measured and the average value was calculated. The calculated average value was used as the mass per unit area (m 2 This is converted to mass (g) per unit area (g / m2). 2 )"

[0072] <Adhesive thickness (mm), non-adhesive thickness (mm), thickness difference (mm)> A sample of 100 mm in the longitudinal direction and 150 mm in the width direction was obtained from the nonwoven fabric. The obtained sample was placed on the stage of a one-shot 3D measuring microscope manufactured by KEYENCE Corporation so as not to wrinkle. Then, a range of 18 mm in height and 100 mm in width was measured with a low-magnification camera (12 times) in the connection mode: auto. At this time, the height of the stage was adjusted so that the nonwoven fabric was included in the measurement range. After the measurement, the "horizontal line mode", which is one of the profile measurement modes, was selected in the analysis software in the device. Then, the height of the convex part and the depth of the concave part when the stage was set as the reference height were read, respectively. A total of 40 points, including 20 convex parts and 20 concave parts, were measured. The average of the total 20 points in the adhesive part (concave part) was calculated, and this was treated as the "thickness of the adhesive part (mm)". Similarly, the average of the total 20 points in the non-adhesive part (convex part) was calculated, and this was treated as the "thickness of the non-adhesive part (mm)". The difference between the thickness (mm) of the bonded portion and the thickness (mm) of the non-bonded portion was treated as the "thickness difference (mm)." Thickness of non-bonded part (mm) - Thickness of bonded part (mm) = Thickness difference between bonded part and non-bonded part (mm)

[0073] SAP loading (g / 44.2cm 2 )〉 A sample of 150 mm in the longitudinal direction and 150 mm in the transverse direction was obtained from the nonwoven fabric, and the mass of each sample obtained was measured (the mass at this time was designated as "mass A (mg)"). The sample was placed between a tray and a sieve (inner diameter 75 mm x inner height 20 mm, mesh size 2.36 mm), and 10 g of SAP was placed in the sieve. The tray, sample, and sieve containing SAP were then set in a sieve shaker (MICRO VIBRO SIFTER MODEL M-2), and the volume was set to 1, and the sample was shaken for 1 min. After shaking, the sample was taken out while being aligned vertically so that the SAP on the sample surface would fall, and the mass of the sample was immediately measured with a balance (the mass at this time was designated as "weight B (mg)"). This was repeated five times, and the average value of mass B and the average value of mass A were obtained, and the difference between the two was calculated. From the difference between the two, the SAP loading amount (g / 44.2 cm 2 ) was calculated. SAP loading amount (g / 44.2cm 2 ) = (Weight B (mg) - Weight A (mg)) The SAP used was superabsorbent resin (product code 1-110-0985) manufactured by Kenis Co., Ltd.

[0074] SAP loading amount (g / 44.2cm 2 ) is 0.45 or more, when SAP is used for sanitary materials such as diapers, the amount of SAP supported on the sheet can be secured, making it easy to realize a product with excellent absorption capacity.

[0075] <Liquid diffusion index (g)> Two samples measuring 150 mm in the longitudinal direction and 150 mm in the transverse direction were obtained from the nonwoven fabric. One sample was coated with 1 g / m 2 Hot melt was applied using a spray-type hot melt gun so that the surface of the sample was evenly coated with 5 g of SAP. Another sample was placed on top of the sample surface on which SAP had been sprinkled, thus producing a three-layered SAP support of sample (nonwoven fabric) / SAP / sample (nonwoven fabric).

[0076] A plate (approximately 800 g) measuring 150 mm square with a 25 mm diameter hole in the center was placed on the SAP support, and 10 ml of blue aqueous solution was dropped from a height of 25 mm above the center hole. The blue aqueous solution was prepared by dissolving Food Blue No. 1 in physiological saline to a concentration of 1%.

[0077] After dropping, the SAP support was photographed 60 seconds later from a height of 200 mm using a digital camera with an effective pixel count of 16.4 million pixels to obtain image data. The obtained image data was printed on A4-size copy paper (whiteness 92%, basis weight 68 g / m) using a RICOH digital full-color multifunction printer MP C5504. 2 ) was color printed. The blue color-printed portion (liquid diffusion portion) of the SAP support was cut out with a cutter, and the total mass of the cut-out paper portion was measured. This measurement was repeated five times, and the average value of each mass (g) obtained was treated as the "liquid diffusion index."

[0078] If the liquid diffusion index is 0.15 or more, the liquid will diffuse sufficiently easily when passed through the SAP, and therefore the liquid will easily permeate throughout the entire SAP.

[0079] <Water flow speed (sec)> A SAP support was prepared in the same manner as in the above-mentioned "Liquid Diffusion Index (-)". A 125 mm square sample was obtained from the SAP support, and the sample was placed on a plastic plate one size larger than the SAP support. Then, the detection plate of the LISTER manufactured by LENZING INSTRUMENTS, which is used in the "STRIKE-THROUGH method" in the standard of EDANA (European Disposables And Nonwovens Association), was placed on the sample. 20 mL of physiological saline was dripped from a height of 30 mm above the detection plate. This drip was considered the first drip, and the same drip was repeated every 30 minutes, and the value displayed by the LISTER after the third drip was treated as the third water flow rate. This measurement was repeated five times, and the average value obtained was treated as the "water flow rate (sec)".

[0080] If the water passing speed (sec) is 20 sec or less, the liquid can be easily transferred from the nonwoven fabric to the SAP quickly.

[0081] Texture A sample of 300 mm in the longitudinal direction and 300 mm in the transverse direction was obtained from the nonwoven fabric. The texture of the sample was then judged by sensory evaluation. The evaluation criteria were the following 5 levels, and the texture was compared with that of Asahi Kasei Corporation's Eltas (trademark) P03040, and judged by the average of 10 people. The average value of the judgment results was treated as the "texture". Evaluation criteria Grade 5: Softer than P03040. Grade 4: Slightly softer than P03040. Grade 3: Equivalent to P03040. Grade 2: Slightly harder than P03040. Grade 1: Harder than P03040.

[0082] Below, Examples 1 to 31 and Comparative Examples 1 to 13 will be described. In the following description, melt flow rate (MFR) is MFR measured in accordance with JIS-K7210 at a temperature of 230°C and a load of 2.16 kg, and melt index (MI) is MI measured in accordance with JIS-K7210 at a temperature of 190°C and a load of 2.16 kg.

[0083] [Example 1] A polypropylene (PP) resin with an MFR of 55 g / 10 min was prepared as the first component, and a high-density polyethylene (HDPE) resin with an MI of 26 g / 10 min was prepared as the second component.

[0084] Resin filaments were extruded at a spinning temperature of 220°C using a side-by-side (S / S) spinneret so that the ratio of the first and second components was PP / PE = 6 / 4 under the condition that the total discharge rate was 0.80g / min·hole. The extruded resin filaments were stretched in the traction zone using the suction force of the conveyor, and then deposited on the conveyor surface through a diffuser. This resulted in a fiber web. The obtained fiber web was partially bonded to each other using hot air at a hot air temperature of 145°C and a hot air speed of 20.0m / sec in a hot air equipment having a hot air outlet with a width W: 0.5mm and a spacing D: 2.0mm (see, for example, Figure 2). This resulted in a 40g / m 2 A nonwoven fabric of

[0085] The obtained nonwoven fabric was coated with an aqueous solution of a water-permeable agent by rotor dampening so that the coating amount was 10% by mass. The aqueous solution of the water-permeable agent was a 5% by mass aqueous solution of polyoxyethylene fatty acid glyceryl and polyether-modified silicone, the liquid temperature of which was adjusted to 20°C. After coating, the aqueous solution of the water-permeable agent was dried by passing it through a cylinder dryer at 125°C, thereby obtaining a nonwoven fabric (Example 1). Various measurement results for Example 1 are shown in the table below.

[0086] [Examples 2 to 21] Nonwoven fabrics were obtained in the same manner as in Example 1, except that the width and interval of the hot air outlet were changed as shown in the table below (Examples 2 to 21).

[0087] [Example 22] Resin filaments were extruded at a spinning temperature of 220°C using an eccentric sheath-core (eS / C) spinneret so that the ratio of the first and second components was PP / PE = 6 / 4 under the condition that the total discharge rate was 0.80g / min·hole. The same resin as in Example 1 was used. The extruded resin filaments were stretched in the traction zone using the suction force of the conveyor, and then deposited on the conveyor surface through a diffuser. This resulted in a fiber web. Next, the fibers were partially bonded to each other in the obtained fiber web by hot air equipment having a hot air outlet with a width W: 1.0 mm and a spacing D: 20.0 mm (see, for example, FIG. 2) at a hot air temperature of 145°C and a hot air speed of 20.0 m / sec. As a result, a 40g / m 2 A nonwoven fabric of

[0088] The obtained nonwoven fabric was coated with an aqueous solution of a water-permeable agent and dried in the same manner as in Example 1, thereby obtaining a nonwoven fabric (Example 22).

[0089] [Example 23] A polyethylene terephthalate (PET) resin having a solution viscosity (ηsp / c) of 0.75 was prepared as a first component, and a high density polyethylene (HDPE) resin similar to that used in Example 1 was prepared as a second component.

[0090] Resin filaments were extruded at a spinning temperature of 300°C using a side-by-side (S / S) spinneret so that the ratio of the first and second components was PET / PE = 6 / 4 under the condition that the total discharge rate was 0.80 g / min·hole. The extruded resin filaments were stretched in the traction zone using the suction force of the conveyor, and then deposited on the conveyor surface through a diffuser. This formed a fiber web. Next, the fibers of the obtained fiber web were partially bonded together using hot air at a hot air temperature of 145°C and a hot air speed of 20.0 m / sec in a hot air equipment having a hot air outlet with a width W: 1.0 mm and a spacing D: 20.0 mm (see, for example, Figure 2), and the fibers were then partially bonded together to a thickness of 40 g / m 2 A nonwoven fabric of

[0091] The obtained nonwoven fabric was coated with an aqueous solution of a water-permeable agent and dried in the same manner as in Example 1, thereby obtaining a nonwoven fabric (Example 23).

[0092] [Examples 24 to 31] Nonwoven fabrics were obtained in the same manner as in Example 1, except that the resin ratio of the first component and the second component, the hot air speed, and / or the hot air temperature were changed as shown in the table below (Examples 24 to 31).

[0093] [Comparative Examples 1 to 8] Nonwoven fabrics were obtained in the same manner as in Example 1, except that the width and interval of the hot air outlet were changed as shown in the table below (Comparative Examples 1 to 8). In Comparative Examples 1, 3, and 6 to 8, the nonwoven fabric was torn in the process of transporting the nonwoven fabric, specifically, in the process of transporting the nonwoven fabric after the hot air was blown thereon until it was wound up, and therefore no nonwoven fabric could be obtained.

[0094] [Comparative Example 9] A polypropylene (PP) resin with an MFR of 55 g / 10 min was prepared as the first component, and a high-density polyethylene (HDPE) resin with an MI of 26 g / 10 min was prepared as the second component.

[0095] Resin filaments were extruded at a spinning temperature of 220°C using a side-by-side (S / S) spinneret so that the ratio of the first and second components was PP / PE = 6 / 4 under the condition that the total output rate was 0.80 g / min·hole. The extruded resin filaments were stretched in the traction zone using the suction force of the conveyor, and then deposited on the conveyor surface through a diffuser. This resulted in a fiber web. The fibers in the obtained fiber web were partially bonded together using hot air at a temperature of 125°C and a hot air speed of 1.2 m / sec. This resulted in a fiber web of 40 g / m 2 The hot air equipment used here did not have a hot air outlet as used in the examples. The obtained nonwoven fabric was coated with an aqueous solution of a water-permeable agent and dried in the same manner as in Example 1, thereby obtaining a nonwoven fabric (Comparative Example 9).

[0096] [Comparative Example 10] A nonwoven fabric was obtained in the same manner as in Comparative Example 9, except that the hot air temperature was changed to 100° C. (Comparative Example 10).

[0097] [Comparative Example 11] Polypropylene (PP) resin with an MFR of 38 g / 10 min was prepared.

[0098] Resin filaments were extruded at a spinning temperature of 240°C using a spinneret equipped with a H-shaped modified spinneret under the condition that the total output was 0.80 g / min·hole. The resin filaments were further extruded toward a moving collection surface using a high-speed airflow traction device with an air jet, thereby obtaining a fiber web. The obtained fiber web was passed between a flat roll set at a temperature of 135°C and a pressure of 60 kg / cm, and an embossing roll (pattern specifications: circular with a diameter of 0.425 mm, staggered arrangement, horizontal spacing of 2.1 mm, vertical spacing of 1.1 mm, and a bonding area ratio of 6.3%), and the fibers were partially bonded together. As a result, a basis weight of 40 g / m 2 A nonwoven fabric of

[0099] The obtained nonwoven fabric was coated with an aqueous solution of a water-permeable agent and dried in the same manner as in Example 1, thereby obtaining a nonwoven fabric (Comparative Example 11).

[0100] [Comparative Example 12] A resin was prepared that had polypropylene (PP) with an MFR of 38g / 10min as the first component (core component) and high density polyethylene (HDPE) with an MI of 26g / 10min as the second component (sheath component). The ratio of the first and second components was set as shown in the table below.

[0101] The above resin was used to prepare staple fibers having a fineness of 2.5 dtex and a cut length of 38 mm. The prepared staple fibers were used as constituent fibers to obtain a fiber web by a carding method. The fibers in the obtained fiber web were partially bonded to each other by hot air at a temperature of 140°C and a hot air speed of 1.0 m / sec. As a result, the basis weight was 40 g / m 2 The nonwoven fabric was obtained

[0102] The obtained nonwoven fabric was coated with an aqueous solution of a water-permeable agent and dried in the same manner as in Example 1, thereby obtaining a nonwoven fabric (Comparative Example 12).

[0103] [Comparative Example 13] A resin was prepared that had polypropylene (PP) with an MFR of 38 g / 10 min as the first component (core component) and high-density polyethylene (HDPE) with an MI of 26 g / 10 min as the second component (sheath component).

[0104] The above resin was used to produce staple fibers with a fineness of 3.3 dtex and a cut length of 38 mm. The produced staple fibers were used as constituent fibers to obtain a fiber web by a carding method. A conveyer with openings with a width W of 2 mm and a spacing D of 3.0 mm arranged in a line was placed on the obtained fiber web (i.e., the fiber web was partially masked by the conveyer), and the fibers were partially bonded to each other using hot air at a temperature of 130°C and a hot air speed of 0.5 m / sec. This resulted in a basis weight of 40 g / m 2 A nonwoven fabric of the above formula was obtained (Comparative Example 13).

[0105] A water-permeable agent aqueous solution was applied to the obtained nonwoven fabric and dried in the same manner as in Example 1, thereby obtaining a nonwoven fabric (Comparative Example 13). In the nonwoven fabric of Comparative Example 13, the thickness of the bonded parts was greater than the thickness of the non-bonded parts.

[0106] In the table below: "S / S (side-by-side type)" and "eS / C (eccentric sheath-core type)" refer to the shape of the spinneret. Since the obtained yarn structure differs depending on this shape, they are listed under the category of "yarn structure." In the "yarn structure" category, "SC" indicates a concentric sheath-core type.

[0107] [Table 1]

[0108] [Table 2]

[0109] [Table 3]

[0110] [Table 4] [Industrial Applicability]

[0111] The present invention is suitable for use in SAP supports because of its excellent liquid diffusibility, SAP loading amount, and water permeability. The present invention is also suitable for use in sanitary materials, such as diaper components (specifically, top sheets, second sheets, etc.). Furthermore, the present invention is also suitable for use in masks, body warmers, tape bases, patch bases, first aid bandage bases, packaging materials, wipe products, medical gowns, bandages, clothing, skin care sheets, etc. [Explanation of symbols]

[0112] 10. Nonwoven Fabrics 1 Adhesive part 1A 1st area 2 Non-adhesive area 2A 2nd area 3,3-2,3-3,3-4,3-5 Hot air outlet 4 aperture W width D interval L1,L2 center line

Claims

1. A nonwoven fabric composed of fibers, A first region having a predetermined number of intersections where the fibers are bonded to each other and having a predetermined thickness; A second region having a smaller number of intersections between the fibers than the first region and a larger thickness than the first region, the second region is present between a plurality of the first regions that are present along a predetermined direction, The width of the first region in the predetermined direction is 0.5 to 20.0 mm, The interval of the first region in the predetermined direction is 2 to 50.0 mm. Nonwoven fabric.

2. The nonwoven fabric according to claim 1 , wherein the predetermined direction is a width direction of the nonwoven fabric.

3. The nonwoven fabric according to claim 1 , wherein the first region and the second region are provided on at least one of the front surface and the back surface of the nonwoven fabric.

4. The first region where a large number of the intersections are bonded and the second region where a large number of the intersections are not bonded are alternately present in the width direction, The thickness of the first region is smaller than the thickness of the second region, The width of the first region is 0.5 to 20 mm; The nonwoven fabric according to claim 1 , wherein the spacing between the first regions is 2 to 50 mm.

5. The nonwoven fabric according to claim 1 , wherein a difference in thickness between the first region and the second region is 0.20 mm or more.

6. When a plurality of arbitrarily selected intersections of the nonwoven fabric are observed, In the first region, more than half of the intersections are observed to be bonded, The nonwoven fabric according to claim 1 , wherein at least half of the intersections observed in the second region are not bonded.

7. The nonwoven fabric according to claim 1 , which is constructed using long fibers.

8. An SAP support comprising the nonwoven fabric of any one of claims 1 to 7.

9. An SAP sheet comprising the SAP support of claim 8 and an SAP.

10. An absorbent article comprising the SAP sheet of claim 9.

11. A sanitary material comprising the nonwoven fabric according to any one of claims 1 to 7.

12. A method for producing a nonwoven fabric comprising the steps of: fusing the web of fibers at predetermined intervals along a predetermined direction; A method for manufacturing nonwoven fabric.

13. The method for producing a nonwoven fabric according to claim 12 , wherein the fusion of the web is performed by blowing hot air onto the web from hot air outlets that are intermittently arranged along the predetermined direction.

14. depositing the fibers on a conveyor to form the web; and forming a first region on the web by blowing hot air onto the web from hot air outlets arranged intermittently in the predetermined direction while the web is being transported by the conveyor; The width of the first region in the predetermined direction is 0.5 to 20.0 mm, The method for producing a nonwoven fabric according to claim 13, wherein the interval between the first regions in the predetermined direction is 2 to 50.0 mm.

15. The width of the hot air outlet in a predetermined direction is 0.5 to 20 mm, The method for producing a nonwoven fabric according to claim 13 or 14, wherein the interval between the hot air outlets in a predetermined direction is 2 to 50 mm.

16. The method for producing a nonwoven fabric according to claim 13 or 14, wherein the hot air has a wind speed of 5 m / sec or more.

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