Nonwoven fabric laminate, stretchable nonwoven fabric laminate, fiber product, and absorbent article

Abstract

A nonwoven fabric laminate according to the present disclosure comprises: an elastic nonwoven fabric; and a stretchable nonwoven fabric disposed on both main surfaces of the elastic nonwoven fabric. The hard phase ratio at 20°C measured by using the pulse nuclear magnetic resonance method is 30.0-52.0%.

Description

Nonwoven fabric laminate, stretchable nonwoven fabric laminate, textile product and absorbent article

[0001] The present disclosure relates to nonwoven laminates, stretchable nonwoven laminates, textiles and absorbent articles.

[0002] In recent years, nonwoven fabrics have been widely used for various purposes due to their excellent breathability and flexibility. Therefore, nonwoven fabrics are required to have various properties according to the purpose, and there is a demand for improvements in these properties.

[0003] Patent Document 1 discloses a nonwoven fabric laminate having excellent stretchability and the like. The nonwoven fabric laminate comprises one or more meltblown nonwoven fabric layers and mixed fiber spunbonded nonwoven fabric layers laminated on both sides thereof. The mixed fiber spunbonded nonwoven fabric layers contain long fibers of a thermoplastic elastomer (A) and long fibers of a thermoplastic resin (B) other than the thermoplastic elastomer (A). Patent Document 1 specifically discloses a method of laminating the meltblown nonwoven fabric layer and the mixed fiber spunbonded nonwoven fabric layer, followed by thermal embossing using an embossing roll to form a nonwoven fabric laminate.

[0004] Patent Document 1: International Publication No. 2007 / 138733

[0005] Depending on the application, such as absorbent articles (e.g., disposable diapers and sanitary napkins) or poultices (e.g., compresses), a nonwoven fabric laminate that exhibits excellent return stress after elongation (i.e., a nonwoven fabric laminate that exhibits excellent stretchability) is required from the viewpoint of fitting well to the skin.

[0006] Furthermore, nonwoven fabrics with excellent stretchability that contain a larger amount of elastic components than conventional fabrics can suffer from localized distortion due to the heat history during manufacturing. In response to demands for design that enhances competitiveness in the market, there is a demand for nonwoven fabric laminates in which the shapes of multiple embossed portions are clearly visible (i.e., nonwoven fabric laminates with excellent embossing visibility).

[0007] In view of the above-mentioned problems, one aspect of the present disclosure aims to provide a nonwoven fabric laminate, a stretchable nonwoven fabric laminate, a textile product, and an absorbent article that are excellent in stretchability and embossing visibility.

[0008] Specific means for solving the above problems include the following aspects: <1> A nonwoven fabric laminate comprising: an elastic nonwoven fabric; and extensible nonwoven fabrics disposed on both main surfaces of the elastic nonwoven fabric, wherein the hard phase ratio at 20°C measured by pulsed nuclear magnetic resonance spectroscopy is 30.0% to 52.0%. <2> The nonwoven fabric laminate according to <1>, wherein the hard phase ratio is 35.0% to 52.0%. <3> The nonwoven fabric laminate according to <1> or <2>, wherein the fibers contained in the elastic nonwoven fabric are made of a resin composition for elastic nonwoven fabrics, the fibers contained in the extensible nonwoven fabric are made of a resin composition for extensible nonwoven fabrics, the resin composition for elastic nonwoven fabrics and the resin composition for extensible nonwoven fabrics each contain an α-olefin copolymer (A) having a ratio (E40 / E23) of the storage modulus E40 at 40°C to the storage modulus E23 at 23°C of 37% or more, the content of the α-olefin copolymer (A) being 70% to 100% by mass with respect to the total amount of the resin composition for elastic nonwoven fabrics, and the content of the α-olefin copolymer (A) being 6% by mass or more but less than 70% by mass with respect to the total amount of the resin composition for extensible nonwoven fabrics. <4> The nonwoven fabric laminate according to <1> or <2>, wherein the resin composition for extensible nonwoven fabrics comprises: a propylene-based polymer (B); and a propylene-based polymer (C) having a density of 0.94 g / cm ３ ~0.97 g / cm ３ The nonwoven fabric laminate according to <3>, further comprising an ethylene polymer (C) represented by the formula (I), wherein the content of the ethylene polymer (C) is 1.0 to 10.0% by mass relative to the total amount of the resin composition for extensible nonwoven fabrics. <5> The nonwoven fabric laminate according to any one of <1> to <4>, further comprising a film layer. <6> A stretchable nonwoven fabric laminate, which is a stretched product of the nonwoven fabric laminate according to any one of <1> to <5>. <7> The stretchable nonwoven fabric laminate according to claim <6>, wherein the nonwoven fabric laminate has a plurality of embossed sections, and the shape retention rate of the embossed sections in the stretched product is 1.40 or less. <8> A textile product comprising the nonwoven fabric laminate according to any one of <1> to <7>. <9> The textile product according to <8>, further comprising engageable engaging means. <10> An absorbent article comprising the nonwoven fabric laminate according to any one of <1> to <7>.

[0009] According to one aspect of the present disclosure, there are provided a nonwoven fabric laminate, a stretchable nonwoven fabric laminate, a textile product, and an absorbent article that are excellent in stretch properties and embossing visibility.

[0010] FIG. 1 is a schematic diagram of a gear stretching device.

[0011] The following describes embodiments of the present disclosure. These descriptions and examples are intended to illustrate the embodiments and do not limit the scope of the embodiments. In the numerical ranges described in this disclosure, the upper or lower limit of one numerical range may be replaced with the upper or lower limit of another numerical range. In the numerical ranges described in this disclosure, the upper or lower limit of that numerical range may be replaced with a value shown in the Examples. In this disclosure, each component may contain multiple corresponding substances. When referring to the amount of each component in a composition in this disclosure, if multiple substances corresponding to each component are present in the composition, the total amount of those multiple substances present in the composition is meant, unless otherwise specified. In this disclosure, the term "process" includes not only independent processes, but also processes that cannot be clearly distinguished from other processes, as long as the purpose of the process is achieved. In this disclosure, numerical ranges indicated using "to" indicate ranges that include the numerical values ​​before and after "to" as the minimum and maximum values, respectively. In the present disclosure, the content of each component in a composition means, when multiple substances corresponding to each component are present in the composition, the total amount of those multiple substances present in the composition, unless otherwise specified.

[0012] (1) Nonwoven Fabric Laminate The nonwoven fabric laminate of the present disclosure comprises an elastic nonwoven fabric and an extensible nonwoven fabric disposed on both main surfaces of the elastic nonwoven fabric, and has a hard phase ratio at 20°C (hereinafter also referred to as "hard phase ratio (20°C)") of 30.0% to 52.0% as measured by pulsed nuclear magnetic resonance (hereinafter also referred to as "pulse NMR") spectroscopy.

[0013] "Elastic nonwoven fabric" refers to a nonwoven fabric having elasticity. "Elasticity" refers to the property of a nonwoven fabric that, when stretched and then stressed, elastically recovers to its pre-stretched shape. The fibers contained in the elastic nonwoven fabric according to the present disclosure are primarily composed of a resin composition for elastic nonwoven fabric. The storage modulus E23 of the resin composition for elastic nonwoven fabric is 25.0 MPa or less. If the storage modulus of the resin composition for elastic nonwoven fabric exceeds 25.0 MPa, the stretch properties of the nonwoven fabric laminate tend to deteriorate. From the viewpoint of improving the stretch properties of the nonwoven fabric laminate, the storage modulus of the resin composition for elastic nonwoven fabric is preferably 22.0 MPa or less, more preferably 18.0 MPa or less. The storage modulus of the resin composition for elastic nonwoven fabric can affect the stretch properties of the nonwoven fabric laminate. "Extensible nonwoven fabric" refers to a nonwoven fabric made of extensible fibers (i.e., a nonwoven fabric having a first property and a second property). The "first property" refers to the property that when an external force is applied to the nonwoven fabric, the outer shape of the nonwoven fabric stretches in one direction. The "second property" refers to the property that the outer shape of the nonwoven fabric does not easily return to its original shape even when the external force applied to the nonwoven fabric is released. Specifically, "extensibility" refers to the property that the maximum elongation is 50% or more, preferably 70% or more, and more preferably 100% or more, and there is almost no elastic recovery. For example, the extensible fibers disclosed in WO 2017 / 006972, WO 2019 / 146656, WO 2020 / 158875, and WO 2022 / 210047 are one of the preferred embodiments of fibers constituting extensible nonwoven fabrics.

[0014] "Nonwoven fabric" refers to a flat collection of fibers that has been given a certain level of structural strength by embossing, excluding weaving, knitting, and papermaking. Nonwoven fabric includes spunbond nonwoven fabric. "Spunbond nonwoven fabric" refers to a nonwoven fabric made from a spunlaid web by one or more bonding methods. "Spunlaid web" refers to a web laminated by spinlaid lamination. "Spinlaid lamination" refers to a method of making a web by extruding molten or dissolved polymers from a nozzle and laminating the filaments onto a moving screen. "Web" refers to a sheet composed solely of fibers.

[0015] Hereinafter, the direction parallel to the moving direction of the screen on which the fibers are stacked is also referred to as the "machine direction (MD)" or "MD." The direction perpendicular to the moving direction of the screen on which the fibers are stacked is also referred to as the "cross-machine direction (CD)" or "CD."

[0016] The machine direction (MD) of a nonwoven fabric can be determined from the nonwoven fabric itself by measuring the tensile strength of the nonwoven fabric. Generally, in the production of nonwoven fabrics, the moving speed of the screen is set to be fast from the viewpoint of productivity. Therefore, when the fibers are stacked on the screen, they tend to be oriented in a direction parallel to the machine direction (MD). As a result, the tensile strength of the nonwoven fabric in the machine direction (MD) is higher than the tensile strength in the cross direction (CD) of the nonwoven fabric. Therefore, the machine direction (MD) of a nonwoven fabric can be determined from the nonwoven fabric itself by measuring the tensile strength of the nonwoven fabric.

[0017] "Pulse NMR method" refers to the measurement of relaxation time (e.g., １ For example, in the measurement of a nonwoven fabric laminate by pulsed NMR, １ The relationship between the magnetization intensity and the spin-spin relaxation time of H is determined, and the hard phase ratio, soft phase ratio, and middle phase ratio of the resin are calculated from this relationship using the solid echo method. "Hard phase" refers to a crystalline phase. "Soft phase" refers to an amorphous phase. "Middle phase" refers to an intermediate phase that does not fall into either the hard phase or the soft phase. "Hard phase ratio" refers to the ratio of the hard phase to the total amount of the hard phase, soft phase, and middle phase. The hard phase ratio indicates the so-called crystallinity. "Soft phase ratio" refers to the ratio of the soft phase to the total amount of the hard phase, soft phase, and middle phase. "Middle phase ratio" refers to the ratio of the middle phase to the total amount of the hard phase, soft phase, and middle phase. The methods for measuring the hard phase ratio, soft phase ratio, and middle phase ratio are the same as those described in the examples. The hard phase ratio, soft phase ratio, and middle phase ratio of the resin add up to 100%, but there is not necessarily a correlation between these phase ratios. For example, if the hard failure rate increases by 5%, the soft failure rate does not necessarily decrease by 5%.

[0018] The nonwoven fabric laminate of the present disclosure has a hard phase ratio within the specified range, and therefore exhibits excellent stretch properties and emboss visibility. This effect is presumed to be due to, but not limited to, the following reasons. An increase in the soft phase ratio at 20°C (hereinafter also referred to as "soft phase ratio (20°C)") of the nonwoven fabric laminate measured by pulse NMR means an increase in the amorphous phase. The amorphous phase is softer and more easily deformed than the crystalline phase. Therefore, the stretch properties of the nonwoven fabric laminate are improved. The hard phase ratio (20°C) of the nonwoven fabric laminate of the present disclosure is 30.0% to 52.0%. As a result, it is presumed that the stretch properties of the nonwoven fabric laminate of the present disclosure are excellent.

[0019] In general, nonwoven fabric laminates with a high soft phase ratio (20°C) have high adhesiveness. Therefore, nonwoven fabric laminates with a high soft phase ratio (20°C) tend to adhere to forming equipment. Furthermore, nonwoven fabric laminates with a high soft phase ratio (20°C) tend to soften. Therefore, the neck-in of nonwoven fabric laminates with a high soft phase ratio (20°C) may be large when producing, for example, absorbent articles. As a result, nonwoven fabric laminates with a high soft phase ratio (20°C) may be unsuitable for mass production. The hard phase ratio (20°C) of the nonwoven fabric laminate of the present disclosure is preferably 30.0% to 52.0%, and the soft phase ratio (20°C) of the nonwoven fabric laminate of the present disclosure is preferably 35.0% or less. Therefore, the nonwoven fabric laminate of the present disclosure tends to adhere less to forming equipment and has relatively small neck-in. As a result, the nonwoven fabric laminate of the present disclosure is superior in handleability during manufacturing and mass productivity. The soft phase ratio (20° C.) of the nonwoven fabric laminate is more preferably 30.5% or less, and particularly preferably 29.5% or less.

[0020] (1.1) Basic Structure The nonwoven fabric laminate is a sheet-like product. The layer structure of the nonwoven fabric laminate is at least three layers, and may be three layers, four layers, or five or more layers.

[0021] The nonwoven fabric laminate has a basis weight of 10 gsm to 120 gsm. For applications requiring flexibility, the nonwoven fabric laminate preferably has a basis weight of 10 gsm to 100 gsm, more preferably 20 gsm to 60 gsm. For applications requiring high tensile strength, the nonwoven fabric laminate preferably has a basis weight of more than 60 gsm to 120 gsm. When the nonwoven fabric laminate has a basis weight of 10 gsm to 120 gsm, the physical properties of the stretchable nonwoven fabric can be adjusted over a wide range depending on the application. The method for measuring the basis weight of the nonwoven fabric laminate is the same as that described in the examples.

[0022] The thickness of the nonwoven fabric laminate is appropriately selected depending on the application of the nonwoven fabric laminate, and is preferably 0.1 mm to 1.0 mm, more preferably 0.15 mm to 0.70 mm.

[0023] When the nonwoven fabric laminate has a three-layer structure, the content of the elastic nonwoven fabric is appropriately selected depending on the application of the nonwoven fabric laminate. The content of the elastic nonwoven fabric may be 10% to 90% by mass, 20% to 80% by mass, 30% to 70% by mass, or 15% to 48% by mass, relative to the total amount of the nonwoven fabric laminate. When the content of the elastic nonwoven fabric is 15% to 48% by mass, the stretch properties of the nonwoven fabric laminate and the mass productivity of the nonwoven fabric laminate and products using the same can be further improved.

[0024] The configuration of the extensible nonwoven fabric arranged on one main surface of the elastic nonwoven fabric and the configuration of the extensible nonwoven fabric arranged on the other main surface of the elastic nonwoven fabric may be the same or different.

[0025] (1.2) Crystallinity (1.2.1) Hard Phase Ratio (20°C) The hard phase ratio (20°C) of the nonwoven fabric laminate is 30.0% to 52.0%. When the hard phase ratio (20°C) is 30.0% to 52.0%, the nonwoven fabric laminate can suppress the occurrence of blocking. "Blocking" refers to a phenomenon in which, when the nonwoven fabric laminate is unwound from the nonwoven fabric roll around which it is wound, the nonwoven fabric laminate cannot be unwound from the nonwoven fabric roll due to adhesion of the nonwoven fabric laminate wound around the nonwoven fabric roll (e.g., the nonwoven fabric laminate breaks). In other words, the nonwoven fabric laminate has excellent mass-producibility.

[0026] The hard phase ratio (20°C) is preferably 35.0% to 52.0%. This provides the nonwoven fabric laminate with a better balance between stretchability and mass-producibility. From the viewpoint of improving the balance between stretchability and mass-producibility of the nonwoven fabric laminate, the hard phase ratio (20°C) is more preferably 38.0% to 50.0%. The hard phase ratio (20°C) may be 30.0% to 52.0%, 35.0% to 52.0%, 38.0% to 52.0%, or 43.0% to 49.0%.

[0027] Methods for adjusting the hard phase ratio (20°C) to 30.0% to 52.0% include changing the crystallinity of the α-olefin copolymer (A); selecting the raw materials, i.e., the α-olefin copolymer (A), the propylene-based polymer (B), and the ethylene-based polymer (C), used in the nonwoven fabric laminate (hereinafter simply referred to as "the raw materials of the nonwoven fabric laminate"); selecting the physical properties of each raw material; adjusting the blending ratio of each raw material (the content ratio of elastic nonwoven fabric); adjusting the content ratio of α-olefin copolymer (A) relative to the total amount of extensible nonwoven fabric in the extensible nonwoven fabric; adjusting the type of fiber constituting the extensible nonwoven fabric (for example, selecting single-component fiber or composite fiber as the fiber constituting the extensible nonwoven fabric), etc.

[0028] (1.2.2) Soft Phase Ratio (20°C) The soft phase ratio (20°C) is not particularly limited and is appropriately selected depending on the application of the nonwoven fabric laminate. The soft phase ratio (20°C) may be 21.5% to 35.0%, 22.0% to 30.5%, 22.0% to 29.5%, or 23.0% to 29.5%. When the soft phase ratio (20°C) is 21.5% to 35.0%, the nonwoven fabric laminate has both good stretch properties and good emboss visibility. Furthermore, the mass productivity of the nonwoven fabric laminate and products using the same is excellent.

[0029] The method for adjusting the soft phase ratio (20°C) is the same as the method exemplified as the method for adjusting the hard phase ratio (20°C).

[0030] (1.2.3) Hard Phase Ratio (-5°C) The hard phase ratio of a nonwoven fabric laminate at -5°C measured by pulse NMR (hereinafter also referred to as "hard phase ratio (-5°C)") is not particularly limited and is appropriately selected depending on the application of the nonwoven fabric laminate. The hard phase ratio (-5°C) may be 60.0% to 71.5%, 64.0% to 71.5%, 67.0% to 71.5%, or 67.5% to 70.0%. When the hard phase ratio (-5°C) is 60.0% to 71.5%, the nonwoven fabric laminate combines good stretch properties with good emboss visibility. Furthermore, the mass productivity of nonwoven fabric laminates and products using the same is excellent.

[0031] The method for adjusting the hard phase ratio (-5°C) to 60.0% to 73.0% is the same as the method exemplified for adjusting the hard phase ratio (20°C) to 30.0% to 52.0%.

[0032] (1.2.4) Middle Phase Ratio (-5°C) The middle phase ratio of the nonwoven fabric laminate at -5°C measured by pulse NMR (hereinafter also referred to as "middle phase ratio (-5°C)") is not particularly limited and is appropriately selected depending on the application of the nonwoven fabric laminate. The middle phase ratio (-5°C) may be 28.7% to 40.0%, 28.5% to 36.0%, 28.5% to 33.0%, or 29.0% to 32.5%. When the middle phase ratio (-5°C) is 28.7% to 40.0%, a nonwoven fabric laminate having both good stretch properties and good emboss visibility can be obtained, and mass production of the nonwoven fabric laminate and products using the same can be achieved.

[0033] The method for adjusting the middle phase ratio (-5°C) is the same as the method exemplified for adjusting the hard phase ratio (20°C).

[0034] (1.2.5) Heat of Fusion ΔH2 The heat of fusion ΔH2 of the nonwoven fabric laminate is not particularly limited and is selected appropriately depending on the application of the nonwoven fabric laminate. The heat of fusion ΔH2 is preferably 25 mJ / mg to 56 mJ / mg, more preferably 40 mJ / mg to 56 mJ / mg, and even more preferably 43 mJ / mg to 56 mJ / mg. When the heat of fusion ΔH2 is 25 mJ / mg to 56 mJ / mg, the nonwoven fabric laminate combines good stretchability and good emboss visibility. In a nonwoven fabric laminate including extensible nonwoven fabrics disposed on both major surfaces of an elastic nonwoven fabric, setting the heat of fusion ΔH2 of the nonwoven fabric laminate to 56 mJ / mg or less is useful for improving the visibility of the embossment of the extensible nonwoven fabric disposed on the major surface of the nonwoven fabric laminate. The lower limit of the heat of fusion ΔH2 affects the peel strength of roll blocking. Furthermore, the mass productivity of nonwoven fabric laminates and products using the same is excellent. "Heat of fusion" is defined as the integrated value of the heat of fusion determined from a melting endothermic curve obtained using a differential scanning calorimeter (DSC) by holding a sample at -100°C for 5 minutes in a nitrogen atmosphere and then raising the temperature at a rate of 10°C / min. The method for measuring the heat of fusion ΔH2 is the same as that described in the Examples.

[0035] The method for adjusting the heat of fusion ΔH2 to 25 mJ / mg to 56 mJ / mg is the same as the method exemplified for adjusting the hard phase ratio (20° C.) to 30.0% to 52.0%.

[0036] (1.3) Physical Properties (1.3.1) Maximum Elongation The maximum elongation of the nonwoven fabric laminate is not particularly limited and is selected appropriately depending on the application of the nonwoven fabric laminate. The maximum elongation is preferably 45% or more, more preferably 70% or more. It is even more preferably 100% or more, and particularly preferably 150% or more. The maximum elongation may be 400% or less, or may be 300% or less. From the viewpoint of obtaining the stretch properties and better stretchability of the nonwoven fabric laminate, it is even more preferable that the maximum elongation is more than 155% and 300% or less. The method for measuring the maximum elongation is the same as that described in the examples.

[0037] Methods for adjusting the maximum elongation to 45% to 400% include the methods exemplified for adjusting the hard phase ratio (20°C) to 30.0% to 52.0%, as well as adjustment of the shape of the embossed portion.

[0038] (1.3.2) 5% Load The 5% load of the nonwoven fabric laminate is not particularly limited and is appropriately selected depending on the application of the nonwoven fabric laminate. The 5% load is preferably 5.00 N / 50 mm / gsm x 100 to 40.00 N / 50 mm / gsm x 100, more preferably 10.00 N / 50 mm / gsm x 100 to 37.00 N / 50 mm / gsm x 100, even more preferably 15.00 N / 50 mm / gsm x 100 to 37.00 N / 50 mm / gsm x 100, and even more preferably 18.00 N / 50 mm / gsm x 100 to 33.00 N / 50 mm / gsm x 100. When the 5% load is 5.00 N / 50 mm / gsm × 100 to 40.00 N / 50 mm / gsm × 100, the embossing visibility is good. For example, when the 5% load is 5.00 N / 50 mm / gsm × 100 to 40.00 N / 50 mm / gsm × 100, neck-in of the nonwoven fabric laminate can be controlled when producing absorbent articles, etc. The method for measuring the 5% load is the same as that described in the examples.

[0039] Methods for adjusting the 5% load to 5.00 N / 50 mm / gsm×100 to 40.00 N / 50 mm / gsm×100 include, in addition to the methods exemplified as methods for adjusting the hard phase ratio (20°C) to 30.0% to 52.0%, adjustment of the shape of the embossed portion; adjustment of the shape of the conjugated fiber; adjustment of the dispersion of the fibers; adjustment of the configuration of the laminate, and the like.

[0040] (1.3.3) Forward Stress The forward stress is not particularly limited and is appropriately selected depending on the application of the nonwoven fabric laminate. The forward stress is preferably 3.80 N / 50 mm / gsm x 100 to 7.00 N / 50 mm / gsm x 100, more preferably 3.80 N / 50 mm / gsm x 100 to 5.00 N / 50 mm / gsm x 100, even more preferably 4.00 N / 50 mm / gsm x 100 to 4.80 N / 50 mm / gsm x 100, and even more preferably 4.10 N / 50 mm / gsm x 100 to 4.80 N / 50 mm / gsm x 100. When the forward stress is 3.80 N / 50 mm / gsm × 100 to 7.00 N / 50 mm / gsm × 100, for example, the ease of wearing an absorbent article using the nonwoven fabric laminate is improved. The forward stress can be measured by the same method as that described in the examples.

[0041] Examples of a method for adjusting the forward stress to 3.80 N / 50 mm / gsm × 100 to 7.00 N / 50 mm / gsm × 100 include the same methods as those exemplified as the method for adjusting the 5% load to 5.00 N / 50 mm / gsm × 100 to 40.00 N / 50 mm / gsm × 100.

[0042] (1.3.4) Return Stress The return stress is not particularly limited and is appropriately selected depending on the application of the nonwoven fabric laminate. The return stress is preferably 1.50 N / 50 mm / gsm x 100 to 2.60 N / 50 mm / gsm x 100, more preferably 1.50 N / 50 mm / gsm x 100 to 2.35 N / 50 mm / gsm x 100, even more preferably 1.50 N / 50 mm / gsm x 100 to 2.20 N / 50 mm / gsm x 100, and even more preferably 1.70 N / 50 mm / gsm x 100 to 2.20 N / 50 mm / gsm x 100. A return stress of 1.50 N / 50 mm / gsm x 100 to 2.60 N / 50 mm / gsm x 100 improves the fit of, for example, an absorbent article when worn. The method for measuring the return stress is the same as that described in the examples.

[0043] Examples of a method for adjusting the return stress to 1.50 N / 50 mm / gsm × 100 to 2.60 N / 50 mm / gsm × 100 include the same methods as those exemplified as the method for adjusting the 5% load to 5.00 N / 50 mm / gsm × 100 to 40.00 N / 50 mm / gsm × 100.

[0044] (1.3.5) Ratio (return stress / forward stress) The ratio of return stress to forward stress (hereinafter also referred to as "ratio (return stress / forward stress)") is not particularly limited and is selected appropriately depending on the application of the nonwoven fabric laminate. The ratio (return stress / forward stress) is preferably 0.40 to 0.60, more preferably 0.41 to 0.55, even more preferably 0.41 to 0.50, and even more preferably 0.42 to 0.50. When the ratio (return stress / forward stress) is 0.40 to 0.60, for example, the balance between wearability and fit of the absorbent article is good.

[0045] Examples of a method for adjusting the ratio (return stress / forward stress) to 0.40 to 0.60 include the same method as the method exemplified as the method for adjusting the 5% load to 5.00 N / 50 mm / gsm × 100 to 40.00 N / 50 mm / gsm × 100.

[0046] (1.4) Embossed Section The nonwoven fabric laminate may have multiple embossed sections. The elastic nonwoven fabric contains multiple fibers (hereinafter also referred to as "elastic fibers"). The extensible nonwoven fabric contains multiple fibers (hereinafter also referred to as "extensible fibers"). The embossed section is formed by bonding a portion of the multiple elastic fibers and a portion of the multiple extensible fibers.

[0047] The "embossed portion" refers to a non-fibrous portion where a part of a plurality of long fibers is bonded. Specifically, the embossed portion is a bonded portion having an area of ​​0.1 mm ２ The presence or absence of embossed portions can be determined by observing the surface or cross section of the fiber assembly and determining whether or not embossed portions (areas of bonded portions) are present. ２ This is done by checking whether or not there is a site where the value is equal to or greater than the threshold.

[0048] The shape of the embossed portion may be a circle, an ellipse, an oval, a square, a diamond, a rectangle, a rectangle, a rectangle, etc. The shape of the embossed portion may be a continuous shape based on these shapes.

[0049] When a nonwoven fabric laminate has multiple embossed portions, the shape retention rate of the embossed portions (hereinafter simply referred to as "shape retention rate") is not particularly limited and is appropriately selected depending on the application of the nonwoven fabric laminate. As the blending amount of elastic component in the nonwoven fabric laminate increases, adhesion to the embossing roll becomes more likely. In addition, the embossed portions may be deformed due to thermal history. As a result, the shape retention rate of the embossments may increase. The shape retention rate is preferably 0.95 to 1.40, more preferably 0.95 to 1.30, and even more preferably 1.10 to 1.25. It has been discovered that a nonwoven fabric laminate with a shape retention rate of 0.95 to 1.40 can be obtained, achieving an excellent balance between stretch properties and embossing visibility. The nonwoven fabric laminate of the present disclosure exhibits a smaller difference between the deformation strain retained by the fibers and the deformation strain retained by the nonwoven fabric laminate during stretching than conventional extensible nonwoven fabrics (i.e., nonwoven fabric laminates comprising an extensible nonwoven fabric that does not contain an α-olefin copolymer). This is presumably why the embossing visibility is improved. In addition, the nonwoven fabric laminate and products using the same are excellent in mass productivity. The shape retention rate was measured in the same manner as in the examples.

[0050] Examples of a method for adjusting the shape retention rate to 0.95 to 1.40 include the same methods as those exemplified as the method for adjusting the 5% load to 5.00 N / 50 mm / gsm×100 to 40.00 N / 50 mm / gsm×100.

[0051] In the nonwoven fabric laminate, the content of the α-olefin copolymer (A) in the elastic nonwoven fabric relative to the total amount of elastic nonwoven fabric (hereinafter also referred to as "elastic nonwoven fabric content (A)") is preferably higher than the content of the α-olefin copolymer (A) in the extensible nonwoven fabric relative to the total amount of extensible nonwoven fabric (hereinafter also referred to as "extensible nonwoven fabric content (A)"). By making the content of the elastic nonwoven fabric (A) higher than the content of the extensible nonwoven fabric (A), a better balance between stretchability and emboss visibility is achieved. In particular, it is more preferable that the content of the extensible nonwoven fabric (A) be 6% by mass or more but less than 70% by mass, and that the content of the elastic nonwoven fabric (A) be 30% by mass or more. It is more preferable that the extensible nonwoven fabric content (A) is 6% by mass or more but less than 50% by mass, and that the elastic nonwoven fabric content (A) is 50% by mass or more, and it is even more preferable that the extensible nonwoven fabric content (A) is 6% by mass or more but less than 60% by mass, and that the elastic nonwoven fabric content (A) is 40% by mass or more. By setting an upper limit for the extensible nonwoven fabric content (A), the peel strength of roll blocking can be improved. By increasing the lower limit for the extensible nonwoven fabric content (A), the stretch properties can be improved. When the nonwoven fabric laminate contains multiple elastic nonwoven fabrics, the configuration of each of the multiple extensible nonwoven fabrics may be the same or different. When the nonwoven fabric laminate contains multiple extensible nonwoven fabrics, the configuration of each of the multiple extensible nonwoven fabrics may be the same or different. The method for measuring the elastic nonwoven fabric content (A) and the extensible nonwoven fabric content (A) is as follows: The nonwoven fabric laminate is solidified with a resin other than polyolefin resin. The solidified product is divided so that the interface between the elastic nonwoven fabric and the extensible nonwoven fabric of the obtained solidified product becomes the cutting surface. The α-olefin copolymer (A) is component-analyzed from each of the obtained multiple divided bodies, and the elastic nonwoven fabric content (A) and the extensible nonwoven fabric content (A) can be calculated.

[0052] (1.5) Elastic Nonwoven Fabric The nonwoven fabric laminate comprises an elastic nonwoven fabric.

[0053] The type of elastic nonwoven fabric is not particularly limited, and examples thereof include spunbond nonwoven fabric, meltblown nonwoven fabric, flash-spun nonwoven fabric, staple fiber, etc. Among these, the type of elastic nonwoven fabric is preferably spunbond nonwoven fabric from the viewpoint of using long fibers in the elastic nonwoven fabric.

[0054] The basis weight of the elastic nonwoven fabric is appropriately selected depending on the application, and is 2 g / m ２ ~120g / m ２ In applications where softness is required, the basis weight of the elastic nonwoven fabric is preferably 2 g / m ２ ~40g / m ２ , more preferably 12 g / m ２ ~37g / m ２ The method for measuring the basis weight of the elastic nonwoven fabric was the same as the method for measuring the total basis weight described in the Examples, except that an elastic nonwoven fabric was used instead of the nonwoven fabric laminate.

[0055] (1.5.1) Elastic Fiber The average fiber diameter of the elastic fiber is preferably 1 μm to 50 μm, more preferably 10 μm to 40 μm. The method for measuring the average fiber diameter of the elastic fiber is as follows. That is, ten 10 mm x 10 mm test pieces are taken from the elastic nonwoven fabric, and the fiber diameter is measured at 20x magnification using a Nikon ECLIPSE E400 microscope. The diameter is measured at 20 random locations for each test piece. The average of the measured values ​​is taken as the average fiber diameter.

[0056] The elastic fibers may be long fibers or short fibers. The cross-sectional shape of the elastic fibers is not particularly limited, and examples thereof include circular, elliptical, and irregular shapes.

[0057] The elastic fiber may be a composite fiber or a single-component fiber. Examples of composite fiber types include sheath-core, side-by-side, islands-in-sea, and side-by-side. Sheath-core composite fibers have only to have a core and a sheath, and may be either a concentric sheath-core type or an eccentric sheath-core type. Eccentric sheath-core composite fibers may have the core exposed on the surface, or the core may not be exposed on the surface. Island-sea composite fibers have a sea phase and multiple island phases.

[0058] (1.5.2) Material The elastic fiber is made of a resin composition for elastic nonwoven fabrics (hereinafter also referred to as "elastic resin composition").

[0059] The elastic resin composition may contain a thermoplastic resin. Examples of the thermoplastic resin include olefin polymers, polyester polymers, polyamide polymers (e.g., nylon-6, nylon-66, and polymetaxylene adipamide), polyimide, ethylene-vinyl acetate copolymer, saponified ethylene-vinyl acetate copolymer, polyvinyl alcohol, polyacrylonitrile, polycarbonate, ionomer, and polybutylene succinate. The thermoplastic resin may be used alone or in combination of two or more.

[0060] Examples of olefin polymers include olefin homopolymers (such as propylene homopolymers and ethylene homopolymers) and olefin copolymers (such as α-olefin copolymers).

[0061] (1.5.2.1) α-Olefin Copolymer The elastic resin composition preferably contains an α-olefin copolymer. This provides the nonwoven fabric laminate with superior stretch properties and stress retention compared to elastic nonwoven fabrics that do not contain an α-olefin copolymer (e.g., elastic nonwoven fabrics made of propylene homopolymer).

[0062] It is more preferable that the elastic resin composition contains an α-olefin copolymer and does not contain an olefin homopolymer. In other words, it is preferable that the elastic nonwoven fabric is an elastic nonwoven fabric containing an α-olefin copolymer (excluding elastic nonwoven fabrics containing an olefin homopolymer). This makes it possible to obtain a nonwoven fabric laminate with better stretch properties and superior stress retention than when an elastic nonwoven fabric not containing an α-olefin copolymer (for example, an elastic nonwoven fabric made of an olefin homopolymer) is used.

[0063] The term "α-olefin copolymer" refers to a copolymer in which two or more copolymerization components having an α-olefin skeleton are copolymerized.

[0064] Examples of copolymerization components having an α-olefin skeleton include α-olefins. Examples of α-olefins include ethylene, propylene, 1-butene, 1-pentene, 3-methyl-1-butene, 4-methyl-1-pentene, 1-hexene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, and 1-eicosene. Among these, the α-olefin copolymer preferably contains an ethylene-propylene copolymer containing ethylene and propylene as copolymerization components, from the viewpoint of providing a nonwoven fabric laminate with lower stress and superior stretch properties.

[0065] In the copolymer of ethylene and propylene, the content of structural units derived from ethylene (hereinafter also simply referred to as "ethylene content") is preferably 1% by mass to 50% by mass, more preferably 5% by mass to 25% by mass, even more preferably 10% by mass to 20% by mass, and particularly preferably 12% by mass to 18% by mass.

[0066] The α-olefin copolymer may be any of an alternating copolymer, a graft copolymer, a block copolymer and a random copolymer.

[0067] The density of the α-olefin copolymer (ASTM D 1505) is preferably 0.850 g / cm ３ ~0.950g / cm ３ , more preferably 0.855 g / cm ３ ~0.900g / cm ３ , more preferably 0.860 g / cm ３ ~0.895g / cm ３ The density of the α-olefin copolymer is a value obtained by measurement in accordance with the density gradient method of JIS K7112 (1999).

[0068] From the viewpoint of improving the stretch properties of the nonwoven fabric laminate, the tensile modulus of the α-olefin copolymer is preferably 30 MPa or less, more preferably 20 MPa or less, and even more preferably 15 MPa or less. The tensile modulus of the α-olefin copolymer is not particularly limited and may be 5 MPa or more. The tensile modulus is a value obtained by measurement using a method in accordance with JIS K7161 (2011).

[0069] The molecular weight distribution (Mw / Mn) of the α-olefin copolymer is preferably 1.5 to 5.0. In terms of obtaining fibers with good spinnability and particularly excellent fiber strength, the molecular weight distribution (Mw / Mn) is more preferably 1.5 to 4.5. The mass average molecular weight (Mw) and number average molecular weight (Mn) of the α-olefin copolymer are values ​​determined by GPC (gel permeation chromatography) under the following conditions. The mass average molecular weight (Mw) is the mass average molecular weight in terms of polystyrene, and the molecular weight distribution (Mw / Mn) is a value calculated from the number average molecular weight (Mn) and mass average molecular weight (Mw) measured in the same manner. <GPC measurement conditions> Column: TOSO GMHHR-H(S)HT Detector: RI detector for liquid chromatography WATERS 150C Solvent: 1,2,4-trichlorobenzene Measurement temperature: 145°C Flow rate: 1.0 ml / min Sample concentration: 2.2 mg / ml Injection volume: 160 μl Calibration curve: Universal Calibration Analysis program: HT-GPC (Ver. 1.0)

[0070] The melt flow rate (MFR) of the α-olefin copolymer is not particularly limited, but is preferably 1 g / 10 min to 100 g / 10 min, more preferably 10 g / 10 min to 80 g / 10 min, even more preferably 15 g / 10 min to 70 g / 10 min, and particularly preferably 15 g / 10 min to 50 g / 10 min. The MFR of the α-olefin copolymer is measured in accordance with ASTM D-1238 under the measurement conditions of 230°C and a load of 2.16 kg.

[0071] The α-olefin copolymer may be a synthetic product or a commercially available product. When the α-olefin copolymer is a synthetic product, it can be prepared by polymerizing or copolymerizing monomers in the presence of a known catalyst (e.g., a Ziegler-Natta catalyst or a metallocene catalyst) by a known polymerization method (e.g., a gas phase method, a bulk method, a slurry method, a solution method, etc.). Commercially available α-olefin copolymers include, for example, Tafmer (manufactured by Mitsui Chemicals, Inc.), Vistamaxx series (manufactured by ExxonMobil Chemical Corporation), and Versify.

[0072] The composition of the α-olefin copolymer can be determined by known methods (for example, infrared spectroscopy (IR) analysis, nuclear magnetic resonance (NMR) analysis, microanalysis, etc.).

[0073] When the α-olefin copolymer is a copolymer of ethylene and propylene, the melting point of the α-olefin is preferably 130°C or lower, more preferably 115°C or lower, even more preferably 100°C or lower, particularly preferably 40°C to 85°C, and even more preferably 40°C to 60°C. The "melting point" is defined as the peak top of the peak observed on the lowest temperature side of a melting endothermic curve obtained using a differential scanning calorimeter (DSC) by holding the sample at -100°C for 5 minutes under a nitrogen atmosphere and then raising the temperature at a rate of 10°C / min. The melting point can be measured by the same method as described in the Examples.

[0074] The content of the α-olefin copolymer is preferably 70% by mass to 100% by mass, more preferably 80% by mass to 100% by mass, even more preferably 90% by mass to 100% by mass, and even more preferably 98% by mass to 100% by mass, relative to the total amount of the elastic resin composition. When the α-olefin copolymer contains an ethylene-propylene copolymer, the content of the ethylene-propylene copolymer is preferably 70% by mass to 100% by mass, more preferably 80% by mass to 100% by mass, even more preferably 90% by mass to 100% by mass, and even more preferably 98% by mass to 100% by mass, relative to the total amount of the elastic resin composition, from the viewpoint of the stretch properties of the nonwoven fabric laminate.

[0075] (1.5.2.2) α-Olefin Copolymer (A) The elastic nonwoven fabric preferably contains an α-olefin copolymer (A) (hereinafter simply referred to as "α-olefin copolymer (A)") having a ratio (E40 / E23) of the storage modulus E40 at 40°C to the storage modulus E23 at 23°C of 37% or more. This makes it easier to suppress the loss of elasticity of the elastic nonwoven fabric in a temperature-varying environment (e.g., 40°C to 23°C). As a result, the nonwoven fabric laminate has excellent stress maintenance.

[0076] From the viewpoint of obtaining a nonwoven fabric laminate with excellent stress retention, the larger the ratio (E40 / E23), the better, and it is more preferably 40% or more, even more preferably 45% or more, and particularly preferably 50% or more. The ratio (E40 / E23) is not particularly limited and may be 100% or less, 95% or less, or 90% or less.

[0077] An example of a method for adjusting the ratio (E40 / E23) of the α-olefin copolymer (A) to fall within the above-mentioned specific range is to use a copolymer of ethylene and propylene as the α-olefin copolymer.

[0078] From the viewpoint of improving the stretch properties of the nonwoven fabric laminate, the storage modulus E23 of the α-olefin copolymer (A) is preferably 30 MPa or less, more preferably 22 MPa or less, even more preferably 20 MPa or less, and particularly preferably 18 MPa or less. The storage modulus E23 of the α-olefin copolymer (A) is preferably 5 MPa or more, more preferably 10 MPa or more. From the viewpoint of making the nonwoven fabric laminate lower stress and more excellent stretch properties, the storage modulus E40 of the α-olefin copolymer (A) is preferably 10 MPa or less, more preferably 9 MPa or less. The storage modulus E40 of the α-olefin copolymer (A) is preferably 3 MPa or more, more preferably 5 MPa or more.

[0079] The elastic nonwoven fabric preferably satisfies condition (a1), which indicates that the elastic nonwoven fabric contains an α-olefin copolymer (A), the content of the α-olefin copolymer (A) is 90% by mass to 100% by mass relative to the total amount of the elastic resin composition, the α-olefin copolymer (A) is a copolymer of ethylene and propylene, and the melting point of the α-olefin copolymer (A) is 130°C or lower.

[0080] (1.5.2.3) Optional Components The elastic resin composition may contain additives within the scope of the present disclosure. Examples of additives include antioxidants, heat stabilizers, weather stabilizers, antistatic agents, slip agents, anti-fogging agents, lubricants, dyes, pigments, natural oils, synthetic oils, waxes, and hydrophilic agents.

[0081] (1.6) Extensible Nonwoven Fabric The nonwoven fabric laminate includes an extensible nonwoven fabric.

[0082] The type of extensible nonwoven fabric is not particularly limited, and examples thereof include spunbond nonwoven fabrics, meltblown nonwoven fabrics, flash-spun nonwoven fabrics, staple fibers, etc. Among these, the type of extensible nonwoven fabric is preferably a spunbond nonwoven fabric, from the viewpoint of using long fibers in the extensible nonwoven fabric.

[0083] The basis weight of the extensible nonwoven fabric is appropriately selected depending on the application, and is 5 g / m ２ ~120g / m ２ In applications where flexibility is required, the basis weight of the extensible nonwoven fabric is preferably 8 g / m ２ ~50g / m ２ , more preferably 13 g / m ２ ~35g / m ２ The method for measuring the basis weight of the extensible nonwoven fabric was the same as the method for measuring the total basis weight described in the Examples, except that an extensible nonwoven fabric was used instead of the nonwoven fabric laminate.

[0084] (1.6.1) Fibers The average fiber diameter of the extendable fibers is preferably 1 μm to 50 μm, more preferably 10 μm to 40 μm. The method for measuring the average fiber diameter of the extendable fibers is the same as the method for measuring the average fiber diameter of the elastic fibers.

[0085] The extendable fiber may be a long fiber or a short fiber. The cross-sectional shape of the extendable fiber is not particularly limited, and examples thereof include a circular, elliptical, and irregular cross-section.

[0086] The extendable fiber may be a composite fiber or a single-component fiber. Composite fibers are fibers whose constituent components are two or more thermoplastic resins, or fibers whose constituent components are two or more thermoplastic resins of the same type but with different viscosities. Single-component fibers are fibers whose constituent component is one type of thermoplastic resin. Examples of types of composite fibers include sheath-core, side-by-side, islands-in-sea, and side-by-side. Sheath-core composite fibers have only to have a core and a sheath, and may be either a concentric sheath-core or an eccentric sheath-core. Here, a single core is present in the fiber cross section. In an eccentric sheath-core composite fiber, the core may be exposed on the surface, or the core may not be exposed on the surface. Islands-in-sea composite fibers have a sea phase and multiple island phases, and the island phases may be continuous or discontinuous. Among these, the extendable fiber is preferably an islands-in-sea composite fiber or a concentric sheath-core composite fiber, more preferably an islands-in-sea composite fiber. When the extendable fiber is an islands-in-sea type composite fiber, the number of thread breakages that occur during spinning of the resin composition that is the raw material for the extendable nonwoven fabric can be reduced compared to when using a core-sheath type composite fiber. The "number of thread breakages" refers to the number of thread breakages that occur within 30 minutes during spinning of the extendable nonwoven fabric. As a result, the productivity of the nonwoven fabric laminate is improved.

[0087] (1.6.2) Material The extensible fiber is made of a resin composition for extensible nonwoven fabrics (hereinafter also referred to as "extensible resin composition").

[0088] The extensible resin composition may contain a thermoplastic resin. Examples of the thermoplastic resin include olefin polymers, polyester polymers, polyamide polymers (e.g., nylon-6, nylon-66, and polymetaxylene adipamide), polyimide, ethylene-vinyl acetate copolymer, saponified ethylene-vinyl acetate copolymer, polyvinyl alcohol, polyacrylonitrile, polycarbonate, ionomer, and polybutylene succinate. The thermoplastic resin may be used alone or in combination of two or more.

[0089] The olefin polymer is preferably a crystalline polymer. Examples of the crystalline component in the crystalline polymer include polypropylene, poly-1-butene, and poly-4-methyl-1-pentene. The olefin polymer may be used alone or in combination of two or more.

[0090] Examples of olefin polymers include olefin homopolymers (such as propylene homopolymers and ethylene homopolymers) and olefin copolymers (such as α-olefin copolymers).

[0091] (1.6.2.1) α-olefin copolymer The extensible resin composition preferably contains an α-olefin copolymer. This provides the nonwoven fabric laminate with superior stretchability and mass productivity compared to when an extensible nonwoven fabric that does not contain an α-olefin copolymer is used.

[0092] Examples of the α-olefin copolymer include the same α-olefin copolymers as those exemplified as the α-olefin copolymer of the elastic resin composition. When the extensible resin composition and the elastic resin composition contain an α-olefin copolymer, the α-olefin copolymer of the extensible resin composition and the α-olefin copolymer of the elastic resin composition may or may not be the same.

[0093] The content of the α-olefin copolymer is preferably 6% by mass or more and less than 70% by mass, more preferably 10% by mass to 45% by mass, even more preferably 15% by mass to 45% by mass, and even more preferably 15% by mass to 35% by mass, relative to the total amount of the extensible resin composition.

[0094] The extensible resin composition preferably contains an α-olefin copolymer (A), the proportion of the α-olefin copolymer (A) relative to the total amount of the extensible nonwoven fabric is 6% by mass to 44% by mass, the α-olefin copolymer (A) is a copolymer of ethylene and propylene, and the melting point of the α-olefin copolymer (A) is preferably 130°C or lower.

[0095] (1.6.2.2) Propylene-Based Polymer (B) The extensible resin composition preferably contains a propylene-based polymer (B).

[0096] The propylene polymer (B) may be a propylene homopolymer or a copolymer of propylene and a monomer other than an α-olefin. The monomer other than an α-olefin may be any known monomer.

[0097] The melting point of the propylene polymer (B) is preferably 140° C. or higher, more preferably 150° C. or higher, still more preferably 155° C. or higher, particularly preferably 157° C. to 165° C. The melting point of the propylene polymer (B) is measured by the same method as described in the examples.

[0098] The melt flow rate (MFR) of the propylene polymer (B) is not particularly limited as long as the extensible resin composition can be melt-spun, and is preferably 1 g / 10 min to 1,000 g / 10 min, more preferably 5 g / 10 min to 500 g / 10 min, and even more preferably 10 g / 10 min to 100 g / 10 min. The MFR of the propylene polymer (B) is measured in accordance with ASTM D-1238 under the measurement conditions of 230°C and a load of 2.16 kg.

[0099] The content of the propylene polymer (B) may be 55.0% by mass to 95.0% by mass, 65.0% by mass to 95.0% by mass, 75.0% by mass to 95.0% by mass, or 85.0% by mass to 95.0% by mass, based on the total amount of the extensible resin composition. The content of the propylene polymer (B) may be 30.0% by mass to 93.0% by mass, 50.0% by mass to 93.0% by mass, 60.0% by mass to 80.0% by mass, 60.0% by mass to 69.0% by mass, or 69.0% by mass to 80.0% by mass.

[0100] The propylene polymer (B) may be a commercially available product.

[0101] (1.6.2.3) Ethylene-Based Polymer (C) The extensible resin composition preferably contains an ethylene-based polymer (C).

[0102] The ethylene polymer (C) may be an ethylene homopolymer or a copolymer of ethylene and a monomer other than an α-olefin. The monomer other than an α-olefin may be any known monomer.

[0103] Examples of ethylene homopolymers include high-pressure low-density polyethylene, linear low-density polyethylene (LLDPE), and high-density polyethylene (HDPE).

[0104] The density of the ethylene polymer (C) is preferably 0.94 g / cm from the viewpoints of the tensile strength, extensibility, and flexibility of the extensible nonwoven fabric. ３ ~0.98g / cm ３ , more preferably 0.94 g / cm ３ ~0.97 g / cm ３ is.

[0105] The melting point of the ethylene polymer (C) is preferably 150°C or higher, more preferably 155°C or higher, and even more preferably 155°C to 165°C.

[0106] The MFR of the ethylene polymer (C) is not particularly limited as long as the melt of the extensible resin composition can be spun, but is preferably 1 g / 10 min to 1,000 g / 10 min, more preferably 2 g / 10 min to 500 g / 10 min, and even more preferably 3 g / 10 min to 100 g / 10 min. The MFR is measured in accordance with ASTM D-1238 under the measurement conditions of 190°C and a load of 2.16 kg.

[0107] The ethylene polymer (C) has a density of 0.94 g / cm ３ ~0.97 g / cm ３ Preferably, the ethylene homopolymer is

[0108] The content of the ethylene polymer (C) is preferably 1.0 to 10.0% by mass, more preferably 3.0 to 8.0% by mass, and even more preferably 5.0 to 7.0% by mass, based on the total amount of the extensible resin composition. When the content of the ethylene polymer (C) is within the above range, the extensibility of the extensible nonwoven fabric is improved.

[0109] (1.6.2.4) Biomass-derived propylene polymer The propylene polymer may be a biomass-derived propylene polymer. The propylene polymer is a propylene polymer (B) or a propylene copolymer. The propylene copolymer includes a copolymer of propylene and one or more α-olefins.

[0110] The term "biomass-derived propylene polymer" refers to a propylene polymer produced from raw material monomers containing biomass-derived propylene. Because the biomass-derived propylene polymer is a carbon-neutral material, it can reduce the environmental impact of producing nonwoven fabric laminates.

[0111] The biomass-derived propylene-containing monomer used as the raw material for the biomass-derived propylene-based polymer can be obtained by cracking biomass naphtha or by synthesis from biomass-derived ethylene. The biomass-derived propylene-based polymer can be obtained by polymerizing the biomass-derived propylene-containing monomer synthesized in this manner using a method similar to that used in the conventional method for using petroleum-derived propylene. A propylene-based polymer synthesized using the bio-derived propylene-containing monomer as the raw material is a biomass-derived propylene-based polymer. The content of the bio-derived propylene-based polymer in the raw material monomers is greater than 0% by mass, and may be 100% by mass or less, relative to the total amount of the raw material monomers. The raw material monomer for the biomass-derived propylene-based polymer may further contain, in addition to bio-derived propylene, propylene derived from fossil fuels such as petroleum, and / or an α-olefin other than ethylene or propylene (e.g., 1-butene, 1-hexene).

[0112] Biomass-derived propylene polymers can also be obtained by polymerizing propylene obtained by synthesis of olefins from methanol (MTO) or propylene from methanol (MTP) using gas generated by pyrolysis of empty fruit bunches (EFB) such as coconut shells. Furthermore, biomass-derived propylene polymers can also be obtained by polymerizing propylene obtained by dehydrating isopropanol produced by fermentation from biomass feedstocks mainly consisting of non-edible plants such as sorghum.

[0113] When the content of radioactive carbon (C14) in the raw material monomer such as propylene is defined as PC14, the content of biomass-derived carbon in the raw material, Pbio (%), can be calculated by the following formula: Formula (2): Pbio (%) = PC14 / 105.5 × 100

[0114] That is, if all the raw materials for a propylene-based polymer are biomass-derived, the content of biomass-derived carbon is theoretically 100%. Therefore, the biomass degree of the biomass-derived propylene-based polymer is 100%. Since fossil fuel-derived raw materials contain almost no C14, the content of biomass-derived carbon in a propylene-based polymer produced only from fossil fuel-derived raw materials is 0%, and the biomass degree of the fossil fuel-derived propylene-based polymer is 0%.

[0115] "Biomass content" indicates the content of carbon derived from biomass and is calculated by measuring radioactive carbon (C14). Carbon dioxide in the atmosphere contains a certain proportion of C14 (approximately 105.5 pMC). Therefore, it is known that the C14 content in plants (e.g., corn) that grow by absorbing carbon dioxide from the atmosphere is also approximately 105.5 pMC. It is also known that fossil fuels contain almost no C14. Therefore, the content of biomass-derived carbon in the raw material can be calculated by measuring the proportion of C14 contained in the total carbon atoms in the propylene-based polymer.

[0116] The biomass content of the propylene-based polymer used as the raw material for the nonwoven fabric laminate is preferably 10% or more.

[0117] The content of the biomass-derived propylene-based polymer used in the nonwoven fabric laminate can be 5% by mass to 99% by mass, 10% by mass to 75% by mass, or 20% by mass to 50% by mass, relative to 100% by mass of the total of the fossil fuel-derived polypropylene resin and the biomass-derived polypropylene resin.

[0118] The propylene-based polymer used as a raw material for the nonwoven fabric laminate may include a propylene-based polymer obtained by recycling, i.e., a so-called recycled polymer. The "recycled polymer" includes a polymer obtained by recycling waste polymer products, and can be produced, for example, by the method described in DE 102019127827 (A1). The recycled polymer may include a marker that identifies it as having been obtained by recycling.

[0119] (1.6.2.5) Preferred Composition The extensible nonwoven fabric preferably satisfies condition (b1), which indicates that the extensible nonwoven fabric contains an α-olefin copolymer (A), the content of the α-olefin copolymer (A) is 6% by mass to 20% by mass relative to the total amount of the extensible resin composition, the α-olefin copolymer (A) is a copolymer of ethylene and propylene, and the melting point of the α-olefin copolymer (A) is 130°C or lower.

[0120] The extensible nonwoven fabric preferably satisfies the conditions (b1) and (b2). The condition (b2) is that the extensible resin composition contains: a propylene-based polymer (B) and a polymer having a density of 0.94 g / cm ３ ~0.97 g / cm ３ and an ethylene polymer (C) of the formula (I), wherein the content of the ethylene polymer (C) is 1.0% by mass to 10.0% by mass relative to the total amount of the resin composition for extensible nonwoven fabrics. This uniformly inhibits oriented crystallization of the propylene polymer inside the fibers, thereby reducing the number of yarn breaks that occur during spinning of the extensible nonwoven fabric. As a result, the productivity of nonwoven fabric laminates is improved.

[0121] When the type of extensible fiber is an islands-in-sea type composite fiber, the extensible fiber preferably has an islands-in-sea structure, the sea phase of which is a propylene-based polymer (B) and the island phase of which is an ethylene-based polymer (C). Oriented crystallization of the sea phase, which is the main component, is inhibited, improving the extensibility of the extensible nonwoven fabric, thereby improving the stretchability and emboss visibility. It is preferred that the propylene-based polymer (B) is a propylene homopolymer, and the ethylene-based polymer (C) is an ethylene homopolymer.

[0122] (1.7) Other Layers The nonwoven fabric laminate may or may not include other layers depending on the application. The other layers are laminated to at least one side of the extensible nonwoven fabric.

[0123] Examples of the other layer include nonwoven fabrics other than elastic nonwoven fabrics and extensible nonwoven fabrics (hereinafter also referred to as "other nonwoven fabrics"), knitted fabrics, woven fabrics, films, etc. The method for further laminating (bonding) other layers to the nonwoven fabric laminate is not particularly limited, and examples include heat embossing, heat fusion methods (e.g., ultrasonic fusion, etc.), mechanical entanglement methods (e.g., needle punching, water jet, etc.), methods using adhesives (e.g., hot melt adhesives, urethane adhesives, etc.), and extrusion lamination.

[0124] The nonwoven fabric laminate may further include a film layer. The film layer may be an elastic film or a non-elastic film. The film layer may have at least one of breathability and moisture permeability, or may not have breathability or moisture permeability. The film layer may be disposed on one side of the nonwoven fabric laminate (i.e., the extensible nonwoven fabric) or on both sides of the nonwoven fabric laminate (i.e., the extensible nonwoven fabric). Examples of lamination configurations include elastic nonwoven fabric / film, elastic nonwoven fabric / film / elastic nonwoven fabric, and film / elastic nonwoven fabric / film. By further including a film layer in the nonwoven fabric laminate, nonwoven fabric laminates suitable for various applications can be provided depending on the properties of the film. The film layer may be heat-welded to the extensible nonwoven fabric, or may be adhered to the extensible nonwoven fabric using an adhesive.

[0125] Other nonwoven fabrics include spunbond nonwoven fabrics, meltblown nonwoven fabrics, wetlaid nonwoven fabrics, drylaid nonwoven fabrics, drylaid pulp nonwoven fabrics, flash-spun nonwoven fabrics, and spread nonwoven fabrics. These nonwoven fabrics may be stretchable or nonstretchable. "Nonstretchable nonwoven fabric" refers to a nonwoven fabric that does not generate return stress after being stretched in the machine direction (MD) or cross direction (CD).

[0126] The film layer is preferably a breathable (moisture-permeable) film. Examples of breathable films include porous films and films made of moisture-permeable thermoplastic elastomers (e.g., polyurethane elastomers, polyester elastomers, polyamide elastomers, etc.). Porous films are obtained by stretching a film made of a thermoplastic resin containing inorganic or organic fine particles to make it porous. Examples of thermoplastic resins used for porous films include olefin polymers. Examples of olefin polymers include high-pressure low-density polyethylene, linear low-density polyethylene (LLDPE), high-density polyethylene (HDPE), polypropylene, and polypropylene random copolymers. The olefin polymer may be a single type or a combination of two or more types. When the breathability and hydrophilicity of the nonwoven fabric laminate do not need to be maintained, a thermoplastic resin film may be used. In particular, using a film made of the same type of thermoplastic resin as the nonwoven fabric laminate is preferred from the viewpoint of increasing the peel strength of the nonwoven fabric laminate containing the film. For example, when the extensible resin composition contains an α-olefin copolymer (A), a propylene-based polymer (B), and an ethylene-based polymer (C), the thermoplastic resin of the non-elastic film is preferably polypropylene, an α-olefin copolymer (e.g., a propylene-based random copolymer), or a combination thereof. When an elastic film is used, the thermoplastic resin of the elastic film is preferably an α-olefin copolymer.

[0127] (1.7) Other Elastic Members Stretchable nonwoven fabrics may be used in combination with elastic members (e.g., elastic threads, etc.). By placing a stretchable elastic member (especially elastic threads) on the stretchable nonwoven fabric, the stretchable nonwoven fabric has even better stretch properties and fit than when no elastic member is combined with the stretchable nonwoven fabric. Stretch sheets combining stretchable nonwoven fabrics with elastic threads are less likely to wrinkle due to shrinkage of the elastic member than when no elastic member is combined with the stretchable nonwoven fabric. As a result, the stretch sheet also has an excellent feel against the skin. Examples of the elastic member include threads (e.g., rubber threads) and strings (e.g., flat rubber). Examples of cross-sectional shapes of the rubber threads include rectangular, square, circular, oval, and polygonal. The elastic member may be a cut piece of stretchable film or stretchable nonwoven fabric, a thermoplastic resin fiber, or a stretchable suture. Materials for the elastic member include synthetic rubber (e.g., styrene-butadiene, butadiene, isoprene, neoprene, etc.), natural rubber, ethylene vinyl acetate copolymer (EVA), elastic polyolefin, polyurethane, etc. The elastic thread may be bonded by any known method (e.g., welding with an adhesive, thermocompression bonding, sewing, etc.).

[0128] (1.8) Preferred Aspect The nonwoven fabric laminate preferably satisfies condition (b3), which indicates that: the fibers contained in the elastic nonwoven fabric are made of a resin composition for elastic nonwoven fabrics; the fibers contained in the extensible nonwoven fabric are made of a resin composition for extensible nonwoven fabrics; the resin composition for elastic nonwoven fabrics and the resin composition for extensible nonwoven fabrics each contain an α-olefin copolymer (A) having a ratio (E40 / E23) of the storage modulus E40 at 40°C to the storage modulus E23 at 23°C of 37% or more; the content of the α-olefin copolymer (A) is 90% to 100% by mass with respect to the total amount of the resin composition for elastic nonwoven fabrics; and the content of the α-olefin copolymer (A) is 6% to 45% by mass with respect to the total amount of the resin composition for extensible nonwoven fabrics.

[0129] The extensible nonwoven fabric preferably satisfies the condition (b3) and also satisfies the condition (b2). In this case, it is more preferable that the propylene polymer (B) is a propylene homopolymer and the ethylene polymer (C) is an ethylene homopolymer.

[0130] (2) Stretchable Nonwoven Fabric Laminate The stretchable nonwoven fabric laminate of the present disclosure is a stretch-processed product of the nonwoven fabric laminate of the present disclosure. The stretchable nonwoven fabric laminate has stretch properties.

[0131] A stretchable nonwoven fabric laminate can be obtained by stretching the nonwoven fabric laminate of the present disclosure. The stretching method is not particularly limited, and conventionally known methods can be used. The stretching method may be a partial stretching method or a full stretching method. The stretching method may be a uniaxial stretching method or a biaxial stretching method. An example of a method for stretching in the machine direction (MD) is a method in which partially fused mixed fibers are passed through two or more nip rolls. In this case, the partially fused nonwoven fabric laminate can be stretched by increasing the rotation speed of the nip rolls in the machine flow direction. Gear stretching can also be performed using a gear stretching device as shown in FIG. 1.

[0132] The stretching ratio is preferably 50% or more, more preferably 100% or more, and even more preferably 200% or more. The stretching ratio is preferably 1000% or less, and more preferably 500% or less.

[0133] In the case of uniaxial stretching, it is preferable that the stretching ratio in the machine direction (MD) or the cross direction (CD) satisfies the above range. In the case of biaxial stretching, it is preferable that the stretching ratio in at least one of the machine direction (MD) and the cross direction (CD) satisfies the above range.

[0134] By stretching the nonwoven fabric laminate at the above-mentioned stretch ratio, the elastic fibers and the extensible fibers are stretched. The extensible fibers undergo plastic deformation and are stretched (i.e., lengthened) according to the stretch ratio. After stretching the nonwoven fabric laminate, when the stress is released, the elastic fibers elastically recover, while the extensible fibers fold without elastic recovery, resulting in a bulky feel in the nonwoven fabric laminate. Furthermore, the extensible fibers tend to become thinner. This is thought to improve flexibility and touch, as well as provide stretch-resistance.

[0135] In the stretchable nonwoven fabric laminate of the present disclosure, the nonwoven fabric laminate preferably has a plurality of embossed portions, and the shape retention rate of the embossed portions in the stretched product is preferably 1.40 or less. This provides a better balance between the stretch properties and embossment visibility of the stretchable nonwoven fabric laminate. In addition, the mass productivity of the stretchable nonwoven fabric laminate and products using the same is excellent. The shape retention rate can be measured using the same method as described in the Examples. The shape retention rate of the stretched product is preferably 0.95 to 1.40, more preferably 0.95 to 1.30, and even more preferably 1.10 to 1.25.

[0136] Examples of a method for adjusting the shape retention rate of a stretched product to 1.40 or less include the same methods as those exemplified as the method for adjusting the 5% load to 5.00 N / 50 mm / gsm × 100 to 40.00 N / 50 mm / gsm × 100.

[0137] (3) Textile Products The textile products of the present disclosure include the nonwoven fabric laminate of the present disclosure or the stretchable nonwoven fabric laminate of the present disclosure. Examples of textile products include, but are not limited to, absorbent articles (e.g., disposable diapers and sanitary products), hygiene articles (e.g., masks), medical articles (e.g., bandages), clothing materials, and packaging materials. The textile products of the present disclosure preferably include the nonwoven fabric laminate or stretchable nonwoven fabric laminate of the present disclosure as an elastic member.

[0138] Preferably, the textile product of the present disclosure further includes an engageable engaging means. By applying an engageable engaging means to the outermost surface of the nonwoven fabric laminate, the textile product of the present disclosure functions as a removable stretch sheet. In addition, the nonwoven fabric laminate of the present disclosure has excellent fit (rebound stress). Therefore, by stretching the textile product of the present disclosure and wrapping it around the human body or an article and engaging it with the engaging means, the nonwoven fabric laminate can be tightly attached to the article or loosely pressed against it. In particular, even if the article to which the textile product of the present disclosure is attached has an uneven shape, the textile product of the present disclosure can conform to the uneven shape of the article. From this perspective, the textile product of the present disclosure is useful as a base material for bandages, gowns, clothing materials, adhesive bandages, and poultices, or as a packaging material. In addition, when the nonwoven fabric laminate does not include other layers, the nonwoven fabric laminate has excellent breathability, resulting in an excellent wearing comfort for the textile product.

[0139] Examples of engageable engaging means include hook-and-loop fasteners with engaging protrusions, mechanical fastenings, removable and re-adhesive adhesive tapes, claws, and clips. The engaging means may be any known engaging means. The engaging means may be provided for the purpose of preventing slippage by increasing surface friction characteristics, or may be used to provide a non-slip finish on a portion of the nonwoven fabric laminate depending on the application. The engaging means may be provided on a portion of the surface of the nonwoven fabric laminate for the purpose of temporarily fastening the tip of a bandage or dressing. Crimped nonwoven fabrics can be used as mechanical fastenings. Among crimped nonwoven fabrics, using a propylene-based polymer makes it possible to construct a nonwoven fabric laminate made solely from polyolefin raw materials, thereby providing a textile product with excellent stretch properties and recyclability.

[0140] (4) Absorbent Articles The absorbent articles of the present disclosure include the nonwoven fabric laminate of the present disclosure or the stretchable nonwoven fabric laminate of the present disclosure. The absorbent articles may further include an absorbent body that absorbs liquid. The nonwoven fabric laminate of the present disclosure or the stretchable nonwoven fabric laminate of the present disclosure may be positioned so as to come into contact with the wearer's skin when the absorbent article is worn.

[0141] (5) Masks The masks of the present disclosure include the nonwoven fabric laminate or stretchable nonwoven fabric laminate of the present disclosure. The masks include a covering portion that covers at least a portion of the wearer's face and ear loops extending from both sides of the covering portion, and the ear loops may include the nonwoven fabric laminate or stretchable nonwoven fabric laminate of the present disclosure.

[0142] (6) Adhesive Materials The adhesive materials of the present disclosure include the nonwoven fabric laminate or stretchable nonwoven fabric laminate of the present disclosure. A "adhesive material" typically comprises a sheet (e.g., nonwoven fabric, woven fabric, etc.) with a paste layer formed on one side. The adhesive material may include a covering portion that covers at least a portion of the wearer's body. The base material of the covering portion may comprise the nonwoven fabric laminate of the present disclosure or the stretchable nonwoven fabric laminate of the present disclosure. The paste layer may be any known paste layer. Specific examples of adhesive materials of the present disclosure include dressings (e.g., compresses, etc.), patches, adhesive sheets for application to the skin, medical dressings, sterile sheets, and medical patches. A drug, medicine, therapeutic agent, patch, topical ointment, transdermal drug, transdermal agent, or patch is applied to the surface of each of the medical dressings, sterile sheets, and medical patches.

[0143] The present disclosure will be described in more detail below based on examples, but the present disclosure is not limited to the following examples. The materials, amounts used, ratios, processing procedures, etc. shown in the following examples can be changed as appropriate without departing from the spirit of the present disclosure. Unless otherwise specified, "parts" means "parts by mass."

[0144] [1] Measurement Methods The physical properties of the nonwoven fabric laminate and the like were measured by the following methods.

[0145] [1.1] Hard phase ratio (20°C) and soft phase ratio (20°C) The hard phase ratio (20°C) and soft phase ratio (20°C) of the nonwoven fabric laminate were measured using the following device and conditions.

[0146] [1.1.1] Apparatus and conditions Apparatus: Bruker "Minispec mq20" (20 MHz) Temperature: 20°C Measurement method: Solid echo method Analyzed nuclide: １ H Repeat time: 4 seconds Number of times: 16

[0147] [1.2] Hard phase ratio (-5°C) and middle phase ratio (-5°C) The hard phase ratio (-5°C) and middle phase ratio (-5°C) of the nonwoven fabric laminate were measured using the following equipment and conditions.

[0148] [1.2.1] Apparatus and conditions Apparatus: Bruker "Minispec mq20" (20 MHz) Temperature: -5°C Measurement method: Solid echo method Analyzed nuclide: １ H Repeat time: 4 seconds Number of times: 16

[0149] [1.3] ΔH2 A 5 mg test piece was taken from the nonwoven fabric laminate. Using a differential scanning calorimeter (Perkin-Elmer, DSC-7), the test piece was held at -100°C for 5 minutes under a nitrogen atmosphere, and then heated at a rate of 10°C / min. The heat of fusion was calculated using the obtained endothermic curve. The integrated value of the heat of fusion was taken as "ΔH2."

[0150] [1.4] Basis weight Ten test pieces of 300 mm (MD) x 250 mm (CD) were taken from the nonwoven fabric laminate. The test pieces were taken from 10 random locations on the nonwoven fabric laminate. The mass (g) of each test piece was measured using a top-pan electronic balance (manufactured by Kensei Kogyo Co., Ltd.). The mass was calculated by subtracting 1 m from the average value of the test pieces. ２ The mass (g) of the nonwoven fabric laminate per unit area was calculated and converted into the mass (g) of the nonwoven fabric laminate per unit area. The converted value was taken as the "basis weight" of the nonwoven fabric laminate.

[0151] [1.5] Maximum Elongation Five test pieces, each measuring 200 mm (MD) x 50 mm (CD), were taken from the nonwoven fabric laminate. The test pieces were taken from five randomly selected locations on the nonwoven fabric laminate. Using a universal tensile tester (IM-201, manufactured by Intesco Co., Ltd.), a tensile test was conducted at a chuck distance of 100 mm and a tensile speed of 300 mm / min, and the elongation of the test pieces (maximum elongation [%]) was measured. The average value of the elongations of the five test pieces was taken as the "maximum elongation" of the nonwoven fabric laminate.

[0152] [1.6] 5% Load Five test pieces, each measuring 200 mm (MD) x 50 mm (CD), were taken from the nonwoven fabric laminate. The test pieces were taken from five randomly selected locations on the nonwoven fabric laminate. A universal tensile tester (IM-201, manufactured by Intesco) was used to conduct a tensile test at a chuck distance of 100 mm and a tensile speed of 300 mm / min. The "5% load" was calculated using the following formula (i). The stretch ratio is expressed by the following formula (ii). Formula (i): 5% load = stress at which the stretch ratio becomes 5% when the test piece is elongated ÷ basis weight × 100 Formula (ii): Stretch ratio = [(chuck distance of test piece after stretching - chuck distance of test piece before stretching (100 mm) / chuck distance of test piece before stretching (100 mm)] × 100

[0153] [1.7] Forward Stress, Return Stress, and Ratio (Return Stress / Forward Stress) Five test pieces measuring 50 mm (CD) x 200 mm (MD) were taken from the nonwoven fabric laminate. Using a universal tensile tester (IM-201, manufactured by Intesco Co., Ltd.), the forward stress at 50% elongation and the return stress at 50% recovery were measured. The test pieces were stretched in the machine direction (MD) to a stretch ratio of 100% under the conditions of a sample width of 50 mm, a chuck distance of 100 mm, and a tensile speed of 200 mm / min. The stretched test pieces were then immediately restored to their original length (100 mm) at 200 mm / min (hereinafter also referred to as the "first elongation and recovery operation"). This was followed by a second first elongation and recovery operation. In the second first elongation and recovery operation, the "forward stress" was calculated using the following formula (iii): The "return stress" was calculated using the following formula (iv). The "ratio (return stress / forward stress)" was calculated using the following formula (v). The stretch ratio is expressed by the following formula (vi). The allowable return stress of a nonwoven fabric laminate is 1.5 N / 50 mm or more. Formula (iii): Forward stress = stress when the stretch ratio becomes 50% when the test piece is stretched / basis weight × 100 Formula (iv): Return stress = stress when the stretch ratio becomes 50% when the test piece is recovered / basis weight × 100 Formula (v): Ratio (return stress / forward stress) = return stress / forward stress Formula (vi): Stretch ratio = [(chuck distance of test piece after stretching - chuck distance of test piece before stretching (100 mm) / chuck distance of test piece before stretching (100 mm)] × 100

[0154] [1.8] Embossing Deformation Five test pieces measuring 50 mm (CD) x 200 mm (MD) were taken from the nonwoven fabric laminate. Ten embossed sections (hereinafter also referred to as "selected embossed sections") were selected from the multiple embossed sections of the test piece. The diagonal length in the machine direction (MD) of the selected embossed sections (hereinafter also referred to as "MD diagonal length") and the diagonal length in the cross direction (CD) of the selected embossed sections (hereinafter also referred to as "CD diagonal length") were measured. The ratio of the MD diagonal length to the CD diagonal length (hereinafter also referred to as "flatness (before stretching)") was calculated. Using a universal tensile tester (IM-201, manufactured by Intesco Co., Ltd.), a test specimen was stretched in the machine direction (MD) to a stretch ratio of 100% under conditions of a chuck distance of 100 mm and a tensile speed of 200 mm / min, and then the stretched test specimen was immediately restored to its original length (100 mm) at 200 mm / min (hereinafter also referred to as the "second stretch recovery operation"). This operation was performed twice. After the second stretch recovery operation was performed twice, the MD diagonal length of the selected embossed section and the CD diagonal length of the selected embossed section were measured. The ratio of the MD diagonal length to the CD diagonal length (hereinafter also referred to as the "flatness (after stretching)") was calculated. The ratio of the flatness (after stretching) to the flatness (before stretching) was defined as the "shape retention rate." If the test piece taken from a commercially available product is smaller than 50 mm (CD) x 200 mm (MD), the same results as this evaluation can be obtained by creating a test piece whose four corners are reinforced with other members. Even if the number of embossed portions contained in the test piece is not 10, the shape retention rate can be evaluated in the same way using the embossed portions that can be confirmed.

[0155] [1.9] Embossment visibility Using the measurement results of the "shape retention rate" in [1.8], the embossment visibility was evaluated according to the following evaluation criteria. An acceptable evaluation result for embossment visibility is "A" or "B".

[0156] [1.9.1] Evaluation criteria "A": Shape retention rate = 0.95 or more and less than 1.25 "B": Shape retention rate = 1.25 or more and less than 1.40 "C": Shape retention rate = 1.40 or more In "A", the degree of deformation of the embossed portion was small even after stretching of the nonwoven fabric laminate. The visibility of the embossed portion in "A" was good. In "B", the degree of deformation of the embossed portion after stretching of the nonwoven fabric laminate began to be confirmed visually. The design quality of the embossed portion in "B" was lower than that of the embossed portion in "A". In "C", the degree of deformation of the embossed portion after stretching of the nonwoven fabric laminate was large. The design quality of the embossed portion in "C" was inferior to that of the embossed portion in "B".

[0157] [1.10] Peel Strength of Roll Blocking A nonwoven fabric laminate was wound onto a core using a winding machine to produce a nonwoven fabric roll. The length of the nonwoven fabric laminate wound onto the core was 50 m. The nonwoven fabric roll was left at room temperature for one week from the time of production of the nonwoven fabric roll. Five test pieces measuring 50 mm (CD) x 200 mm (MD) were taken from the core of the left nonwoven fabric roll. The test pieces were nonwoven fabric laminates in a state where two or more sheets were overlapped. The overlapping test pieces were peeled off in the machine direction (MD) by 70 mm to produce an evaluation sample. The peel strength of the overlapping nonwoven fabric laminate was measured using a universal tensile tester (IM-201, manufactured by Intesco Co., Ltd.) under conditions of a chuck distance of 100 mm and a tensile speed of 500 mm / min. The results are shown in Table 1. The acceptable peel strength is preferably 25 mN / 50 mm or less, more preferably 10 mN / 50 mm or less.

[0158] [1.11] Storage modulus E40 The storage modulus E40 of the "α-olefin copolymer" was measured using the following equipment and conditions: Temperature: 40°C Equipment: RSA-III (manufactured by TI Instruments) Deformation mode: Tensile mode Temperature range: -20°C to 120°C Heating rate: 2°C / min Deformation frequency: 10 Hz Initial strain: 0.1% Measurement temperature range: 0.3°C Environment: Nitrogen atmosphere

[0159] [1.12] Storage modulus E23 The storage modulus E23 of the "α-olefin copolymer" was measured using the following equipment and conditions: Temperature: 23°C Equipment: RSA-III (manufactured by TI Instruments) Deformation mode: Tensile mode Temperature range: -20°C to 120°C Heating rate: 2°C / min Deformation frequency: 10 Hz Initial strain: 0.1% Measurement temperature range: 0.3°C Environment: Nitrogen atmosphere

[0160] [1.13] Melting point Using a differential scanning calorimeter (Perkin-Elmer, DSC-7), a 5 mg sample was held at −100° C. for 5 minutes under a nitrogen atmosphere and then heated at a rate of 10° C. / min. The peak top observed at the lowest temperature side of the melting endothermic curve was taken as the “melting point.”

[0161] [2] Preparation of Materials The following materials were prepared as raw materials for the nonwoven fabric laminate.

[0162] [2.1] Outer layer (extensible nonwoven fabric) <α-olefin copolymer (A)> - "α-olefin copolymer" (manufactured by ExxonMobil, product name "Vistamaxx™ 7050BF", composition: propylene / ethylene copolymer, MFR (230°C, load 2.16 kg): 48 g / 10 min, ethylene content: 13% by mass, tensile modulus: 9.82 MPa, storage modulus E23: 17.4 MPa, storage modulus E40: 8.77 MPa, ratio (E40 / E23): 50.4%, melting point: 44.4°C) <Propylene polymer (B)> - "h-pp" (propylene homopolymer, MFR (measured in accordance with ASTM D1238 at a temperature of 230°C and a load of 2.16 kg): 60 g / 10 min, density: 0.91 g / cm ３ , melting point: 160°C) <Ethylene polymer (C)> "HDPE" (high-density polyethylene, MFR (measured in accordance with ASTM D1238 at a temperature of 190°C and a load of 2.16 kg): 5 g / 10 min, density: 0.95 g / cm ３ , melting point: 134 ° C.)

[0163] [2.2] Intermediate layer (elastic nonwoven fabric) <α-olefin copolymer (A)> "α-olefin copolymer" (manufactured by ExxonMobil, product name "Vistamaxx™7050BF", composition: propylene / ethylene copolymer, MFR (230°C, load 2.16 kg): 48 g / 10 min, ethylene content: 13 mass%, tensile modulus: 9.82 MPa, storage modulus E23: 17.4 MPa, storage modulus E40: 8.77 MPa, ratio (E40 / E23): 50.4%, melting point: 44.4°C)

[0164] [3] Nonwoven Fabric Laminate [3.1] Example 1 84 parts by mass of "h-pp," 10 parts by mass of "α-olefin copolymer," and 6 parts by mass of "HDPE" were mixed to obtain an extensible resin composition. The extensible resin composition was introduced into a single-screw extruder (screw diameter: 75 mmφ) and melted. The molding temperature of the extensible resin composition was 220°C. The molten extensible resin composition was supplied to a spinneret to extrude long fibers. The spinneret had 1,093 holes. The spinneret die temperature was 220°C. The resin output rate was 23.0 kg / hour. The long fibers extruded from the spinneret were stretched at an air speed of 2,941 m / min while being cooled with air (20°C) and deposited on a moving screen. This produced a first layer of spunbond web (extensible web). The fibers contained in the first layer of the spunbond web were islands-in-the-sea fibers. The length of the screen in the cross direction (CD) was 320 mm.

[0165] An elastic resin composition composed of an "α-olefin copolymer" was prepared. The elastic resin composition was introduced into a single-screw extruder (screw diameter: 75 mmφ) and melted. The molding temperature of the elastic resin composition was 245°C. The melt of the extensible resin composition was supplied to a spinneret to extrude long fibers. The spinneret had 1,093 holes. The spinneret's die temperature was 245°C. The resin output was 29.4 kg / hour. The long fibers extruded from the spinneret were stretched at an air speed of 4,118 m / min while being cooled with air (20°C), and then deposited on the first layer of spunbond web deposited on a moving screen. This resulted in a second layer of spunbond web (elastic web). The fibers contained in the second layer of web were single-component fibers.

[0166] A third spunbond web (extensible web) was deposited on the second spunbond web deposited on the moving screen in the same manner as the first spunbond web, resulting in a three-layer stack. The fibers contained in the third spunbond web were islands-in-the-sea fibers.

[0167] The three-layer stack was subjected to a heat and pressure treatment using an embossing roll (embossed area ratio: 18%, embossing temperature: 60°C) to produce a nonwoven fabric laminate. The maximum point elongation of the first and third spunbond nonwoven fabric layers in the nonwoven fabric laminate was 50%. The nonwoven fabric laminate included an elastic nonwoven fabric (i.e., the second spunbond nonwoven fabric) and extensible nonwoven fabrics (i.e., the first and third spunbond nonwoven fabric layers) disposed on both major surfaces of the elastic nonwoven fabric. The content of the elastic nonwoven fabric was 42 mass% of the total weight of the nonwoven fabric laminate. The "embossed area ratio" refers to the area ratio of the multiple protrusions on the embossing roll. The measurement results for the nonwoven fabric laminate are shown in Table 1.

[0168] [3.2] Examples 2 to 6 and Comparative Example 1 Nonwoven fabric laminates were obtained in the same manner as in Example 1, except that the extensible resin composition was changed. The maximum point elongation of the first and third spunbond nonwoven fabric layers in the nonwoven fabric laminates of Examples 2 to 6 and Comparative Example 1 was 50%. The extensible resin composition of Comparative Example 1 contained 94 parts by mass of "h-pp," 0 parts by mass of "α-olefin copolymer," and 6 parts by mass of "HDPE." The extensible resin composition of Example 2 contained 74 parts by mass of "h-pp," 20 parts by mass of "α-olefin copolymer," and 6 parts by mass of "HDPE." The extensible resin composition of Example 3 contained 64 parts by mass of "h-pp," 30 parts by mass of "α-olefin copolymer," and 6 parts by mass of "HDPE." The extensible resin composition of Example 4 contained 54 parts by mass of "h-pp", 40 parts by mass of "α-olefin copolymer", and 6 parts by mass of "HDPE". The extensible resin composition of Example 5 contained 44 parts by mass of "h-pp", 50 parts by mass of "α-olefin copolymer", and 6 parts by mass of "HDPE". The extensible resin composition of Example 6 contained 34 parts by mass of "h-pp", 60 parts by mass of "α-olefin copolymer", and 6 parts by mass of "HDPE".

[0169]

[0170] In Table 1, "α-OC (A)" indicates α-olefin copolymer (A), and "C3 / C2" indicates a copolymer of propylene and ethylene.

[0171] [4] Results The hard phase ratio (20°C) of Comparative Example 1 was outside the range of 30.0% to 52.0%. Therefore, the return stress of the nonwoven fabric laminate of Comparative Example 1 was not 1.5 N / 50 mm or more. The embossment visibility of Comparative Example 1 was evaluated as "C." These results revealed that the nonwoven fabric laminate of Comparative Example 1 was not a "nonwoven fabric laminate excellent in stretch properties and embossment visibility."

[0172] The hard phase ratios (20°C) of Examples 1 to 6 were within the range of 30.0% to 52.0%. Therefore, the return stress of the nonwoven fabric laminates of Examples 1 to 6 was 1.50 N / 50 mm or more. The embossment visibility of Examples 1 to 6 was evaluated as "A" or "B." These results demonstrate that the nonwoven fabric laminates of Examples 1 to 6 are "nonwoven fabric laminates excellent in stretch properties and embossment visibility."

[0173] The disclosure of Japanese Patent Application No. 2024-057802, filed on March 29, 2024, is incorporated herein by reference in its entirety. All documents, patent applications, and technical standards mentioned herein are incorporated herein by reference to the same extent as if each individual document, patent application, and technical standard was specifically and individually indicated to be incorporated by reference.

Claims

1. A nonwoven fabric laminate comprising: an elastic nonwoven fabric; and an extensible nonwoven fabric disposed on both main surfaces of the elastic nonwoven fabric, wherein the hard phase ratio at 20°C measured by pulsed nuclear magnetic resonance spectroscopy is 30.0% to 52.0%.

2. The nonwoven fabric laminate according to claim 1, wherein the hard phase ratio is 35.0% to 52.0%.

3. The nonwoven fabric laminate according to claim 1, wherein the fibers contained in the elastic nonwoven fabric are made of a resin composition for elastic nonwoven fabrics, the fibers contained in the extensible nonwoven fabric are made of a resin composition for extensible nonwoven fabrics, the resin composition for elastic nonwoven fabrics and the resin composition for extensible nonwoven fabrics each contain an α-olefin copolymer (A) having a ratio (E40 / E23) of storage modulus E40 at 40°C to storage modulus E23 at 23°C of 37% or more, the content of the α-olefin copolymer (A) is 70% to 100% by mass with respect to the total amount of the resin composition for elastic nonwoven fabrics, and the content of the α-olefin copolymer (A) is 6% by mass or more and less than 70% by mass with respect to the total amount of the resin composition for extensible nonwoven fabrics.

4. The resin composition for extensible nonwoven fabrics comprises a propylene polymer (B) and a propylene copolymer having a density of 0.94 g / cm ３ ~0.97 g / cm ３ and an ethylene polymer (C) represented by the formula (I), wherein the content of the ethylene polymer (C) is 1.0% by mass to 10.0% by mass based on the total amount of the resin composition for extensible nonwoven fabrics.

5. The nonwoven laminate of claim 1, further comprising a film layer.

6. A stretchable nonwoven fabric laminate, which is a stretched product of the nonwoven fabric laminate according to claim 1.

7. The stretchable nonwoven fabric laminate according to claim 6, wherein the nonwoven fabric laminate has a plurality of embossed sections, and the shape retention rate of the embossed sections in the stretched product is 1.40 or less.

8. A textile product comprising the nonwoven fabric laminate according to any one of claims 1 to 7.

9. The textile product of claim 8, further comprising engageable engagement means.

10. An absorbent article comprising the nonwoven fabric laminate according to any one of claims 1 to 7.

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