Stretchable nonwoven fabric, fiber product, and sanitary material

Abstract

A stretchable nonwoven fabric according to the present disclosure comprises: stretchable fibers that contain a thermoplastic polyurethane elastomer (A); and extensible fibers that contain a thermoplastic resin (B) different from the thermoplastic polyurethane elastomer (A). The contained amount of the thermoplastic polyurethane elastomer (A) is 25-39 mass% with respect to the total amount of the stretchable nonwoven fabric. The 5%-tensile strength per area weight of the stretchable nonwoven fabric is 0.20 [N / 50 mm / gsm] or more. The 5%-tensile strength indicates the load required for pulling the stretchable nonwoven fabric until the elongation percentage reaches 5% in the machine direction (MD) of the stretchable nonwoven fabric.

Description

Elastic nonwoven fabrics, textile products and sanitary materials

[0001] The present disclosure relates to stretchable nonwoven fabrics, textile products, and hygiene materials.

[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 spunbond nonwoven fabric having elastic recovery properties. The spunbond nonwoven fabric contains long fibers made of a thermoplastic polyurethane elastomer (A) having a hardness of 75 to 85. The thermoplastic polyurethane elastomer (A) contains ethylene bisoleic acid amide and / or crosslinked organic fine particles.

[0004] Patent Document 1: International Publication No. 2011 / 129433

[0005] A long spunbond nonwoven fabric may be sandwiched between multiple pairs of rolls and transported. At this time, tension may be applied to the spunbond nonwoven fabric by the multiple pairs of rolls in a direction parallel to the transport direction of the spunbond nonwoven fabric so that the spunbond nonwoven fabric does not slacken.

[0006] Spunbond nonwoven fabrics with excellent stretchability tend to shrink in the width direction perpendicular to the machine direction when tension is applied in a direction parallel to the machine direction. The machine direction is parallel to the warp of the spunbond nonwoven fabric (the machine direction, MD, of the nonwoven fabric) (hereinafter also referred to as the "machine direction (MD)"). The width direction is parallel to the weft of the spunbond nonwoven fabric (the cross direction, CD, hereinafter also referred to as the "cross direction (CD)"). If a spunbond nonwoven fabric shrinks too much in the width direction, it may be difficult to process. Therefore, there is a demand for stretchable nonwoven fabrics that are less likely to shrink in the cross direction (CD) even when tension is applied in the machine direction (MD) (in other words, stretchable nonwoven fabrics with reduced width shrinkage). However, when a nonwoven fabric is simply made by increasing the proportion of fibers with high tensile stiffness in the nonwoven fabric, although improvement in width shrinkage is observed, the stretchability of the nonwoven fabric tends to decrease as the proportion of thermoplastic elastomer fibers is reduced.

[0007] In view of the above-mentioned problems, the present disclosure aims to provide a stretchable nonwoven fabric, a textile product, and a sanitary material that have excellent stretch properties and are suppressed from shrinking in width.

[0008] Specific means for solving the above problems include the following aspects. <1> A stretchable nonwoven fabric comprising: stretchable fibers containing a thermoplastic polyurethane elastomer (A); and extensible fibers containing a thermoplastic resin (B) different from the thermoplastic polyurethane elastomer (A), wherein the content of the thermoplastic polyurethane elastomer (A) is 25% by mass to 39% by mass relative to the total amount of the stretchable nonwoven fabric, and the 5% tensile strength per basis weight of the stretchable nonwoven fabric is 0.20 [N / 50 mm / gsm] or more, and the 5% tensile strength represents the load required to pull the stretchable nonwoven fabric in the machine direction (MD) of the stretchable nonwoven fabric until an elongation of 5% is achieved. <2> The stretchable nonwoven fabric according to <1>, comprising: at least one stretchable spunbonded nonwoven fabric layer containing the stretchable fibers; and at least one extensible spunbonded nonwoven fabric layer containing the extensible fibers. <3> The stretchable nonwoven fabric according to <2>, wherein the ratio of the basis weight of the extensible spunbonded nonwoven fabric layer to the basis weight of the stretchable nonwoven fabric is 15% to 35%. <4> The stretchable nonwoven fabric according to <2> or <3>, wherein the extensible spunbonded nonwoven fabric layer is a surface layer. <5> The stretchable nonwoven fabric according to any one of <2> to <4>, wherein the extensible spunbonded nonwoven fabric layer is included in an intermediate layer. <6> The stretchable nonwoven fabric according to any one of <1> to <5>, wherein the thermoplastic resin (B) includes at least one of polyethylene and a propylene-based polymer. <7> The stretchable nonwoven fabric according to any one of <1> to <6>, wherein the basis weight of the stretchable nonwoven fabric is 10 gsm to 120 gsm. <8> A textile product comprising the stretchable nonwoven fabric according to any one of <1> to <7>. <9> A hygiene material comprising the stretchable nonwoven fabric according to any one of <1> to <7>.

[0009] According to one embodiment of the present disclosure, there are provided a stretchable nonwoven fabric, a textile product, and a sanitary material that have excellent stretch properties and suppressed width shrinkage.

[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 stages 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 described in stages. 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, this refers to the total amount of those multiple substances present in the composition, 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, when the composition contains multiple substances corresponding to each component, the content of each component in the composition means the total amount of the multiple substances present in the composition, unless otherwise specified. ２ is synonymous with.

[0012] (1) Stretchable Nonwoven Fabric The stretchable nonwoven fabric of the present disclosure comprises stretchable fibers containing a thermoplastic polyurethane elastomer (A) (hereinafter also referred to as "TPU (A)") and extensible fibers containing a thermoplastic resin (B) (hereinafter also referred to as "TR (B)") different from the thermoplastic polyurethane elastomer (A). The content of the thermoplastic polyurethane elastomer (A) (hereinafter also referred to as "TPU content") is 25% to 39% by mass based on the total weight of the stretchable nonwoven fabric. The 5% tensile strength per basis weight of the stretchable nonwoven fabric is 0.20 [N / 50 mm / gsm] or greater. The 5% tensile strength refers to the load required to pull the stretchable nonwoven fabric in the machine direction (MD) of the stretchable nonwoven fabric (hereinafter also referred to as "machine direction (MD)") until the stretchable nonwoven fabric reaches an elongation of 5%. The 5% tensile strength of the stretchable nonwoven fabric is measured using the same method as described in the Examples.

[0013] In this disclosure, "elastic nonwoven fabric" refers to a nonwoven fabric having elastic properties. "Nonwoven fabric" refers to a flat fiber assembly that has a predetermined level of structural strength obtained by at least one of physical and chemical methods, excluding weaving, knitting, and papermaking. "Nonwoven fabric with elastic properties" refers to a nonwoven fabric that, when stretched and then stressed, recovers to its original shape before stretching due to its elastic properties. Specifically, a nonwoven fabric with elastic properties refers to a nonwoven fabric whose stress at 50% elongation relative to the stress at 50% recovery is 4.0 or less. "Elastic fiber" refers to a fiber that can be used to produce an elastic nonwoven fabric (in other words, a fiber that imparts elastic properties to a nonwoven fabric). "Elastic fiber" can also be referred to as a fiber composed of a thermoplastic resin composition that constitutes an elastic nonwoven fabric. "Extensible fiber" refers to a fiber that can be used to produce an extensible nonwoven fabric (in other words, a fiber that imparts extensibility to a nonwoven fabric). For example, the fibers constituting the extensible nonwoven fabrics disclosed in WO 2017 / 006972, WO 2019 / 146656, WO 2020 / 158875, and WO 2022 / 210047 are preferred embodiments of extensible fibers. "Extensible nonwoven fabric" refers to a nonwoven fabric having extensibility. "Extensible nonwoven fabric" refers to a nonwoven fabric having a first property and a second property. "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. "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, an extensible nonwoven fabric has an elongation rate of 50% or more, preferably 70% or more, and more preferably 100% or more, and exhibits almost no elastic recovery. "Elongation" refers to the percentage of the increase in length due to stretching relative to the natural length in an unstretched state. "Machine direction (MD) of an elastic nonwoven fabric" refers to the direction in which a moving screen travels when the elastic nonwoven fabric comprises a spunbond nonwoven fabric. "Spunbond nonwoven fabric" refers to a nonwoven fabric made by one or more bonding methods to a spunlaid web. "Spunlaid web" refers to a web laminated by spunlay lamination."Spunlay lamination" refers to a method in which molten or dissolved polymer is extruded through a nozzle, the filaments are stretched with cooled air, and laid onto a moving screen to form a web.

[0014] The stretchable nonwoven fabric of the present disclosure has the above-described configuration, and therefore has excellent stretchability and suppressed width shrinkage.

[0015] Hereinafter, the cross-machine direction (CD) of the elastic nonwoven fabric will also be referred to simply as "cross-machine direction (CD)." When the elastic nonwoven fabric includes a spunbond nonwoven fabric, the "cross-machine direction (CD) of the elastic nonwoven fabric" refers to the direction perpendicular to the direction of travel of the moving screen.

[0016] When the elastic nonwoven fabric includes a spunbonded nonwoven fabric, the tensile strength in the machine direction (MD) of the elastic nonwoven fabric can be determined from the elastic nonwoven fabric itself by measuring the tensile strength in the machine direction (MD). Generally, in the production of elastic nonwoven fabrics, the moving speed of the screen is set to a high speed from the viewpoint of productivity. Therefore, the long fibers contained in the web tend to be oriented in a direction parallel to the machine direction (MD) when laminated on the screen. As a result, the tensile strength in the machine direction (MD) of the elastic nonwoven fabric is higher than the tensile strength in the cross direction (CD) of the elastic nonwoven fabric. Therefore, the machine direction (MD) of the elastic nonwoven fabric can be determined from the elastic nonwoven fabric itself by measuring the tensile strength of the elastic nonwoven fabric.

[0017] (1.1) Physical Properties The 5% tensile strength per unit area of ​​the stretchable nonwoven fabric is 0.20 [N / 50 mm / gsm] or more, and from the viewpoint of imparting flexibility while suppressing width shrinkage, it is preferably 0.20 [N / 50 mm / gsm] to 0.80 [N / 50 mm / gsm], more preferably 0.22 [N / 50 mm / gsm] to 0.70 [N / 50 mm / gsm], and even more preferably 0.25 [N / 50 mm / gsm] to 0.60 [N / 50 mm / gsm].

[0018] The reason for focusing on the 5% tensile strength per unit area of ​​the elastic nonwoven fabric in order to suppress width shrinkage of the elastic nonwoven fabric is to quantitatively evaluate the tensile strength at a small elongation rate. At a tensile strength at an elongation rate of 10% or more, the elastic nonwoven fabric may yield due to tensile deformation, and the Young's modulus of the elastic nonwoven fabric may not be accurately evaluated. The technical significance of a high 5% tensile strength per unit area of ​​an elastic nonwoven fabric is that it is an elastic nonwoven fabric that is resistant to deformation even when an external force is applied (i.e., a stiff elastic nonwoven fabric).

[0019] Methods for adjusting the 5% tensile strength per unit weight of a stretchable nonwoven fabric to 0.20 [N / 50 mm / gsm] or more include, for example, increasing the proportion of high tensile stiffness fibers in the entire stretchable nonwoven fabric, making the stretchable nonwoven fabric a "mixed fiber configuration of stretchable fibers and extensible fibers," making the stretchable nonwoven fabric a "layer configuration including a stretchable spunbonded nonwoven fabric layer and an extensible spunbonded nonwoven fabric layer," "arranging high tensile stiffness fibers somewhere in the thickness direction of the stretchable nonwoven fabric," adjusting the type and content of resin used for the extensible fibers, and adjusting the unit weight of each layer. As a result of research, it was found that when the proportion (mass %) of extensible fibers in the entire stretchable nonwoven fabric exceeds 60%, the 5% tensile strength per unit weight of the stretchable nonwoven fabric becomes 0.20 [N / 50 mm / gsm] or more. This is because the extensible fibers with high tensile stiffness increase the 5% tensile strength per unit weight.

[0020] The stretch ratio of the elastic nonwoven fabric is preferably 4.0 or less. The stretch ratio is determined by the stress at 50% recovery (S ２ ) of the elastic nonwoven fabric at 50% elongation (S １ ) ratio (hereinafter referred to as "(S １ / S ２ The stretch ratio of the elastic nonwoven fabric is preferably greater than 1.5 and less than 3.0, and more preferably greater than 1.5 and less than 2.5, from the viewpoint of the stretch characteristics of the elastic nonwoven fabric. The method for measuring the stretch ratio of the elastic nonwoven fabric is the same as that described in the examples.

[0021] Methods for adjusting the stretch ratio of a stretchable nonwoven fabric to 4.0 or less include, for example, increasing the proportion of thermoplastic elastomer fibers, making the stretchable nonwoven fabric a "mixed fiber structure of stretchable fibers and extensible fibers," making the stretchable nonwoven fabric a "layer structure including a stretchable spunbond nonwoven fabric layer and an extensible spunbond nonwoven fabric layer," "arranging fibers with high tensile stiffness in any direction in the thickness direction of the stretchable nonwoven fabric," adjusting the type and content of resin used in the stretchable fibers, and adjusting the basis weight of each layer. Increasing the amount of thermoplastic elastomer reduces the 5% tensile strength. Therefore, to achieve both the stretch ratio and the 5% tensile strength, the TPU content is preferably 25% to 39%. Furthermore, the ratio of the basis weight of the extensible spunbond nonwoven fabric layer to the basis weight of the stretchable nonwoven fabric may be 15% to 50%, more preferably 15% to 40%, and even more preferably 15% to 35%. By setting the TPU content to 25% to 39% and the basis weight ratio of the extensible spunbond nonwoven fabric layer to 15% to 35%, both the stretchability and 5% tensile strength are improved. It is believed that by setting the TPU content within the above range and by partially bundling the extensible fibers in the thickness direction of the elastic nonwoven fabric, an improvement in the 5% tensile strength was achieved while maintaining stretchability. The proportion (mass %) of extensible fibers in the entire elastic nonwoven fabric is preferably more than 60% and not more than 75%, and more preferably more than 60% and not more than 70%.

[0022] The tensile strength in the machine direction (MD) of the elastic nonwoven fabric (hereinafter also referred to as "tensile strength") is not particularly limited and can be appropriately selected depending on the application and basis weight of the elastic nonwoven fabric. When the basis weight of the elastic nonwoven fabric is 10 gsm to 30 gsm, the tensile strength of the elastic nonwoven fabric may be 5 N / 50 mm or more and less than 35 N / 50 mm. When the basis weight of the elastic nonwoven fabric is 30 gsm to 65 gsm, the tensile strength of the elastic nonwoven fabric is more preferably 35 N / 50 mm or more and less than 65 N / 50 mm. When the basis weight of the elastic nonwoven fabric is more than 65 gsm, the tensile strength of the elastic nonwoven fabric is preferably 65 N / 50 mm to 180 N / 50 mm, more preferably 80 N / 50 mm to 120 N / 50 mm. When the tensile strength of the elastic nonwoven fabric is 5 N / 50 mm or more, tearing of the elastic nonwoven fabric can be suppressed when tension in the machine direction (MD) is applied to the elastic nonwoven fabric. From this viewpoint, the tensile strength of the elastic nonwoven fabric is preferably 15 N / 50 mm or more, and more preferably 25 N / 50 mm or more. The method for measuring the tensile strength of the elastic nonwoven fabric is the same as that described in the Examples. Methods for adjusting the tensile strength include orienting the fibers in the machine direction (MD), increasing fusion between fibers, and increasing the basis weight ratio of the extensible spunbond nonwoven fabric layer.

[0023] The elongation percentage in the machine direction (MD) of the elastic nonwoven fabric (hereinafter also referred to as "elongation percentage") is not particularly limited and is selected appropriately depending on the application of the elastic nonwoven fabric. The elongation percentage of the elastic nonwoven fabric is preferably 100% to 400%, more preferably 120% to 300%. An elongation percentage of 100% to 400% can prevent breakage of the elastic nonwoven fabric when tension in the machine direction (MD) is applied to the elastic nonwoven fabric, and can also prevent breakage of the elastic nonwoven fabric during gear processing. The method for measuring the elongation percentage of the elastic nonwoven fabric is the same as the method described in the Examples. A method for adjusting the elongation percentage to 100% to 400% is to make the elongation of all fibers constituting the elastic nonwoven fabric 100% or more.

[0024] (1.2) Basic Structure The stretchable nonwoven fabric is a sheet-like material. The type of stretchable nonwoven fabric is not particularly limited. The stretchable nonwoven fabric preferably includes a spunbonded nonwoven fabric. The stretchable nonwoven fabric may include other nonwoven fabrics, woven fabrics, knitted fabrics, paper, etc., different from the spunbonded nonwoven fabric. The other nonwoven fabric may be a staple fiber nonwoven fabric or a long fiber nonwoven fabric. Examples of other nonwoven fabrics include wet-laid nonwoven fabrics, dry-laid nonwoven fabrics, air-laid nonwoven fabrics, dry pulp nonwoven fabrics, carded nonwoven fabrics, parallel nonwoven fabrics, cross-laid nonwoven fabrics, random nonwoven fabrics, spunlaid nonwoven fabrics, melt-blown nonwoven fabrics, flash-spun nonwoven fabrics, chemically bonded nonwoven fabrics, hydroentangled nonwoven fabrics, needle-punched nonwoven fabrics, stitch-bonded nonwoven fabrics, and thermally bonded nonwoven fabrics.

[0025] The basis weight of the stretchable nonwoven fabric is preferably 10 gsm to 120 gsm, and is selected appropriately depending on the application of the stretchable nonwoven fabric. From the viewpoint of achieving both flexibility and stretchability, the basis weight of the stretchable nonwoven fabric is more preferably 20 gsm to 100 gsm, and even more preferably 25 gsm to 90 gsm. The method for measuring the basis weight of the stretchable nonwoven fabric is the same as the method described in the examples.

[0026] The thickness of the stretchable nonwoven fabric is not particularly limited and is selected appropriately depending on the intended use of the stretchable nonwoven fabric. The thickness of the stretchable nonwoven fabric is preferably 0.10 mm to 5.00 mm, more preferably 0.15 mm to 3.00 mm, and even more preferably 0.20 mm to 1.00 mm. When the thickness of the stretchable nonwoven fabric is 0.10 mm to 5.00 mm, an appropriate thickness can be selected depending on the intended use of the stretchable nonwoven fabric. The method for measuring the thickness of the stretchable nonwoven fabric is the same as the method described in the Examples.

[0027] The TPU content is 25% to 39% by mass. This allows both 5% tensile strength and stretchability to be achieved. From the viewpoint of achieving both 5% tensile strength and stretchability, the TPU content is more preferably 29% to 38% by mass, and even more preferably 33% to 37% by mass.

[0028] The elastic nonwoven fabric may contain, in addition to elastic fibers and extensible fibers, other fibers different from each of the elastic fibers and extensible fibers.

[0029] (1.3) Layer structure The layer structure of the stretchable nonwoven fabric is selected appropriately depending on the application of the stretchable nonwoven fabric, and may be a single-layer structure made of mixed fiber nonwoven fabric, or a multi-layer structure. "Mixed fiber nonwoven fabric" refers to a nonwoven fabric in which fibers of different resins are mixed at the spinning stage. When the stretchable nonwoven fabric has a multi-layer structure, it is preferable that the stretchable nonwoven fabric has at least one layer of mixed fiber nonwoven fabric. The stretchable nonwoven fabric may also include other layers described below.

[0030] The elastic nonwoven fabric preferably comprises at least one elastic spunbond nonwoven fabric layer (hereinafter also referred to as "elastic SB layer") and at least one extensible spunbond nonwoven fabric layer (hereinafter also referred to as "extensible SB layer"). The elastic SB layer comprises the elastic fiber. The extensible SB layer comprises the extensible fiber. The elastic SB layer of the elastic nonwoven fabric is preferably a mixed fiber nonwoven fabric. By including the extensible fiber in the elastic SB layer, the adhesive strength between the elastic SB layer and the extensible SB layer is excellent, and the 5% tensile strength and stretch properties can be improved.

[0031] The term "elastic spunbond nonwoven fabric layer" refers to a spunbond nonwoven fabric layer that has elastic properties. Specifically, the term "elastic spunbond nonwoven fabric layer" refers to a spunbond nonwoven fabric layer in which the ratio of the stress at 50% elongation to the stress at 50% recovery (stress at 50% elongation / stress at 50% recovery) is 4.0 or less. The term "extensible spunbond nonwoven fabric layer" refers to a spunbond nonwoven fabric layer that has extensibility. The term "extensible spunbond nonwoven fabric layer" refers to a spunbond nonwoven fabric layer that has an elongation rate of 50% or more, preferably 70% or more, and more preferably 100% or more, and that has almost no elastic properties.

[0032] Hereinafter, a stretchable nonwoven fabric including a stretchable SB layer and an extensible SB layer will also be referred to as a "stretchable nonwoven fabric laminate."

[0033] The elastic nonwoven fabric laminate of the present disclosure includes an elastic SB layer and an extensible SB layer, thereby enabling width shrinkage to be further suppressed while maintaining stretch properties. This effect is presumably due to, but not limited to, the following reasons: When an elastic nonwoven fabric laminate includes an extensible SB layer, deformation tends to be less likely to occur up to a larger tensile load. While width shrinkage of an elastic nonwoven fabric is thought to be caused by Poisson deformation, the results of the present disclosure have shown that Poisson deformation can be controlled by changing the balance of the arrangement of various fibers in the thickness direction.

[0034] When the stretchable nonwoven fabric laminate includes a stretchable SB layer and an extensible SB layer, the stretchable nonwoven fabric laminate may have a two-layer structure, a three-layer structure, or a four-layer or greater structure. When the stretchable nonwoven fabric laminate has a three-layer structure, the stretchable nonwoven fabric laminate may be a first laminate or a second laminate. The first laminate is formed by laminating an extensible SB layer, an extensible SB layer, and an extensible SB layer in this order. The second laminate is formed by laminating an extensible SB layer, an extensible SB layer, and an extensible SB layer in this order. Note that when the stretchable nonwoven fabric laminate has a four-layer or greater structure, the stretchable nonwoven fabric laminate may be formed by laminating at least one of an extensible SB layer and an extensible SB layer on a three-layer first laminate, or by laminating at least one of an extensible SB layer and an extensible SB layer on a three-layer second laminate. In the first laminate and the second laminate, by increasing the TPU content in the stretchable SB layer relative to the TPU content in the extensible SB layer, the balance between stretch properties and width shrinkage can be further improved. In particular, a more preferred embodiment is one in which the TPU content in the stretchable SB layer is 0% by mass or more but less than 20% by mass, and 40% by mass or more but less than 70% by mass. An even more preferred embodiment is one in which the TPU content in the stretchable SB layer is 0% by mass or more but less than 10% by mass, and 40% by mass or more but less than 60% by mass. Furthermore, a more preferred embodiment is one in which the TPU content of each layer is within the above-mentioned range, and the TPU content in the stretchable nonwoven fabric laminate and the basis weight ratio of the stretchable SB layer are within the ranges of the present disclosure. When the stretchable nonwoven fabric laminate includes multiple stretchable SB layers, the configurations of the multiple stretchable SB layers may be the same or different. When the elastic nonwoven fabric laminate includes multiple extensible SB layers, the configuration of each of the multiple extensible SB layers may be the same or different. The method for measuring the TPU content in the elastic SB layer or extensible SB layer is as follows. The thermoplastic resin used as the raw material for the elastic nonwoven fabric (the elastic nonwoven fabric laminate) is solidified with a resin other than TPU and polyolefin resin. The solidified product is divided so that the interface between the elastic SB layer and the extensible SB layer of the obtained solidified product becomes the cutting surface.By eluting the TPU from each of the resulting divided bodies, the TPU content of the stretchable SB layer and the TPU content of the extensible SB layer can be calculated.

[0035] When the elastic nonwoven fabric laminate comprises an elastic SB layer and an extensible SB layer, the machine direction (MD) of the elastic SB layer and the machine direction (MD) of the extensible SB layer are the same, and the cross direction (CD) of the elastic SB layer and the cross direction (CD) of the extensible SB layer are the same.

[0036] When the stretchable nonwoven fabric laminate includes a first laminate, it is a preferred embodiment that the stretchable SB layer is a surface layer. By using the stretchable SB layer in direct contact with the skin, the wearer of the stretchable nonwoven fabric laminate is less likely to experience discomfort (e.g., a sticky feeling). Furthermore, by not having the stretchable SB layer in direct contact with the gear stretching machine, partial adhesion of the stretchable nonwoven fabric to the gear stretching machine is suppressed. As a result, processability can be improved.

[0037] When the stretchable nonwoven fabric laminate includes a second laminate, it is a preferred embodiment that the stretchable SB layer is included in the intermediate layer. By including an extensible spunbond nonwoven fabric layer in the intermediate layer of the stretchable nonwoven fabric laminate, the contractile forces of both nonwoven fabric surface layers in the lamination direction of the stretchable nonwoven fabric laminate during stretching become more equal, making the stretchable nonwoven fabric laminate less likely to curl. As a result, the stretchable nonwoven fabric laminate is more likely to maintain a flat shape and is easier to handle. The "intermediate layer of the stretchable nonwoven fabric laminate" refers to a layer other than the two outer layers in a stretchable nonwoven fabric laminate consisting of three or more layers.

[0038] When the elastic nonwoven fabric laminate comprises an elastic SB layer and an extensible SB layer, the basis weight ratio (i.e., composition ratio) of the elastic SB layer to the extensible SB layer of the elastic nonwoven fabric laminate is appropriately selected depending on the application of the elastic nonwoven fabric laminate. The ratio of the basis weight of the extensible SB layer to the basis weight of the elastic SB layer (basis weight of extensible SB layer / basis weight of extensible SB layer) is preferably 15 / 85 to 50 / 50, more preferably 15 / 85 to 40 / 60, and even more preferably 15 / 85 to 35 / 65. When the elastic nonwoven fabric laminate comprises multiple elastic SB layers, the basis weight of the elastic SB layer refers to the sum of the basis weights of the multiple stretchable SB layers. When the elastic nonwoven fabric laminate comprises multiple stretchable SB layers, the basis weight of the extensible SB layer refers to the sum of the basis weights of the multiple stretchable SB layers.

[0039] (1.3.1) Elastic spunbond nonwoven fabric layer The elastic SB layer contains elastic fibers. The elastic SB layer may consist of only elastic fibers, or may further contain fibers other than the elastic fibers (e.g., extensible fibers) in addition to the elastic fibers.

[0040] The elastic SB layer is preferably made of elastic fibers and extensible fibers, which allows the elastic nonwoven fabric laminate to be less susceptible to adhesion to processing machines and stickiness to the skin during use, compared to when the elastic SB layer is made of elastic fibers alone.

[0041] When the elastic SB layer is composed of an elastic fiber and an extensible fiber, the content of TPU (A) relative to the total amount of the elastic SB layer is preferably 10% by mass to 90% by mass. This improves the stretch properties of the elastic nonwoven fabric laminate. From the viewpoints of the stretch properties and flexibility of the elastic nonwoven fabric laminate, the content of TPU (A) is more preferably 20% by mass or more, and even more preferably 30% by mass or more. From the viewpoint of the processability (e.g., stickiness resistance) of the elastic nonwoven fabric laminate, the content of TPU (A) is more preferably 70% by mass or less, and even more preferably 60% by mass or less. When the elastic nonwoven fabric laminate includes an elastic SB layer and an extensible SB layer, the content of TPU (A) in the elastic SB layer is preferably 40% by mass or more and 70% by mass or less, and more preferably 40% by mass or more and 60% by mass or less. The content of the TPU (A) in the extensible SB layer is preferably 0% by mass or more and less than 20% by mass, and more preferably 0% by mass or more and less than 10% by mass.

[0042] The basis weight per layer of the stretchable SB layer may be 2 gsm to 120 gsm, 2 gsm to 40 gsm, or 12 gsm to 37 gsm. The method for measuring the basis weight of the stretchable SB layer is the same as the method for measuring the basis weight described in the examples.

[0043] (1.3.2) Stretchable Spunbond Nonwoven Fabric Layer The stretchable SB layer contains stretchable fibers. The stretchable SB layer preferably contains more than 90% by mass and not more than 100% by mass of stretchable fibers, and more preferably consists solely of stretchable fibers. In addition to the stretchable fibers, the stretchable SB layer may further contain fibers other than the stretchable fibers (e.g., stretchable fibers) in a range of less than 10% by mass relative to the mass of the stretchable SB layer. When the stretchable nonwoven fabric laminate contains a stretchable SB layer and a stretchable SB layer, the stretchable fibers contained in the stretchable SB layer and the stretchable fibers in the stretchable SB layer may be fibers of the same resin composition or fibers of different resin compositions. From the perspective of increasing the interlayer peel strength and improving the 5% tensile strength of the stretchable nonwoven fabric laminate, it is preferable that the resin compositions of each layer are all polyolefin-based resin compositions, and the difference in melting points between the polyolefin-based resin compositions of the stretchable fibers in each layer is preferably 30°C or less.

[0044] The content of the thermoplastic resin (B) in the extensible SB layer is preferably 80% by mass or more and 100% by mass or less, more preferably 90% by mass or more and 100% by mass or less, and even more preferably 100% by mass, based on the total amount of the extensible spunbonded nonwoven fabric layer, which can increase the tensile strength by 5%.

[0045] The basis weight per layer of the stretchable SB layer may be 2 gsm to 120 gsm, 2 gsm to 40 gsm, or 12 gsm to 37 gsm. The method for measuring the basis weight of the stretchable SB layer is the same as the method for measuring the basis weight described in the examples.

[0046] The ratio of the basis weight of the extensible SB layer to the basis weight of the elastic nonwoven fabric (i.e., the elastic nonwoven fabric laminate) (hereinafter also referred to as "basis weight ratio (extensible SB layer)") is preferably 15% to 35%. This allows the elastic nonwoven fabric laminate to have better 5% tensile strength and more excellent stretch properties. From the viewpoint of improving the 5% tensile strength, the basis weight ratio (extensible SB layer) is more preferably 17% or more, and even more preferably 20% or more. From the viewpoint of not excessively reducing the stretch properties, the basis weight ratio (extensible SB layer) is more preferably 40% or less, even more preferably 35% or less, and particularly preferably 30% or less.

[0047] (1.4) Elastic Fiber The elastic fiber comprises TPU (A).

[0048] The average fiber diameter of the elastic fiber is preferably 60 μm or less, more preferably 50 μm or less, and even more preferably 40 μm or less. The average fiber diameter of the elastic fiber is preferably 1 μm or more, more preferably 10 μm or more, and even more preferably 20 μm or more.

[0049] The average fiber diameter of the elastic fibers was measured as follows: Ten 10 mm x 10 mm test pieces were taken from the elastic nonwoven fabric, and the fiber diameters were read in μm units to the first decimal place at a magnification of 20x using a Nikon ECLIPSE E400 microscope. The diameters were measured at 20 random locations for each test piece, and the average value was the average fiber diameter.

[0050] The elastic fiber may be a long fiber or a short fiber. From the viewpoint of 5% strength, the elastic fiber is preferably a long fiber spunbond nonwoven fabric. The cross-sectional shape of the elastic fiber is not particularly limited, and examples thereof include a substantially circular shape, an elliptical shape, and an irregular shape.

[0051] The stretchable fiber may be a composite fiber or a monocomponent fiber. Composite fibers preferably have two or more thermoplastic resins as constituent components. Examples of composite fibers include sheath-core, side-by-side, islands-in-sea, and side-by-side types. 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-in-sea composite fibers have a sea phase and multiple island phases.

[0052] (1.4.1) Material The elastic fiber contains TPU (A), or may consist solely of TPU (A). TPU (A) may be a known thermoplastic polyurethane elastomer.

[0053] (1.4.1.1) Thermoplastic polyurethane elastomer (A) The TPU (A) is preferably a thermoplastic polyurethane elastomer (hereinafter also referred to as "TPU (a)") having a hardness (JIS K-7311: Type A durometer) in the range of 70 to 90 (preferably 75 to 85, more preferably 80 to 83) and containing at least one of ethylene bisoleic acid amide and crosslinked organic fine particles. Thermoplastic polyurethane elastomers are also collectively referred to as "TPU."

[0054] When the hardness of the TPU is 70 to 90, the elastic nonwoven fabric has certain elastic properties even if the elastic nonwoven fabric contains extensible fibers.

[0055] The mass average molecular weight (Mw) of the TPU (a) is preferably 125,000 to 200,000, more preferably 130,000 to 180,000. The melt viscosity of the TPU (a) is preferably 0.9 × 10 ４ (dPa・s)~1.4×10 ４ (dPa·s).

[0056] (1.4.1.1.1) Polyol Polyol is one of the components constituting TPU (a). Polyol is a polymer having two or more hydroxyl groups per molecule. Examples of polyols include polyester polyol, polyoxyalkylene polyol, polytetramethylene ether glycol, polycaprolactone polyol, and polycarbonate diol. These polyols may be used alone or in combination of two or more.

[0057] The polyester polyol can be obtained, for example, by condensation polymerization of at least one low-molecular-weight polyol and at least one carboxylic acid (e.g., low-molecular-weight dicarboxylic acid, oligomeric acid, etc.). Examples of low-molecular-weight polyols include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, glycerin, trimethylolpropane, 3-methyl-1,5-pentanediol, hydrogenated bisphenol A, and hydrogenated bisphenol F. Examples of low-molecular-weight dicarboxylic acids include glutaric acid, adipic acid, sebacic acid, terephthalic acid, isophthalic acid, and dimer acid. The number-average molecular weight of the polyester polyol is preferably 500 to 4,000.

[0058] Polyoxyalkylene polyols can be obtained, for example, by addition polymerization of alkylene oxides (e.g., propylene oxide, ethylene oxide, butylene oxide, styrene oxide, etc.) with at least one relatively low molecular weight dihydric alcohol. The number average molecular weight of the polyoxyalkylene polyol is preferably 200 to 8,000.

[0059] Tetramethylene ether glycol is obtained by ring-opening polymerization of tetrahydrofuran, and the number average molecular weight of the tetramethylene ether glycol is preferably 250 to 4,000.

[0060] Polycaprolactone polyol can be obtained by ring-opening polymerization of ε-caprolactone.

[0061] Polycarbonate diol is obtained by a condensation reaction between a dihydric alcohol (e.g., 1,4-butanediol, 1,6-hexanediol, etc.) and a carbonate compound (e.g., dimethyl carbonate, diethyl carbonate, diphenyl carbonate, etc.). The number average molecular weight of the polycarbonate diol is preferably 500 to 3,000.

[0062] (1.4.1.1.2) Isocyanate Compound The isocyanate compound is one of the components constituting the TPU (a). The isocyanate compound has two or more isocyanate groups per molecule. Examples of the isocyanate compound include aromatic aromatic polyisocyanates, aliphatic aromatic polyisocyanates, and alicyclic aromatic polyisocyanates.

[0063] Examples of aromatic polyisocyanates include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, an isomer mixture of tolylene diisocyanate in a mass ratio (2,4-isomer:2,6-isomer) of 80:20 (TDI-80 / 20), and an isomer mixture of tolylene diisocyanate in a mass ratio (2,4-isomer:2,6-isomer) of 65:35 (TDI-65 / 35); 4,4'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, 2,2'-diphenylmethane diisocyanate, and any isomer mixture of these diphenylmethane diisocyanates; toluylene diisocyanate, xylylene diisocyanate, tetramethylxylylene diisocyanate, paraphenylene diisocyanate, and naphthalene diisocyanate.

[0064] Examples of aliphatic polyisocyanates include ethylene diisocyanate, trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, octamethylene diisocyanate, nonamethylene diisocyanate, 2,2'-dimethylpentane diisocyanate, 2,2,4-trimethylhexane diisocyanate, decamethylene diisocyanate, butene diisocyanate, 1,3-butadiene-1,4-diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, 1,6,11-undecamethylene triisocyanate, 1,3,6-hexamethylene triisocyanate, 1,8 2,5,7-trimethyl-1,8-diisocyanate-5-isocyanatemethyloctane, bis(isocyanate ethyl)carbonate, bis(isocyanate ethyl)ether, 1,4-butylene glycol dipropyl ether-ω,ω'-diisocyanate, lysine isocyanate methyl ester, lysine triisocyanate, 2-isocyanateethyl-2,6-diisocyanate hexanoate, 2-isocyanatepropyl-2,6-diisocyanate hexanoate, and bis(4-isocyanate-n-butylidene)pentaerythritol.

[0065] Examples of alicyclic polyisocyanates include isophorone diisocyanate, bis(isocyanatemethyl)cyclohexane, dicyclohexylmethane diisocyanate, cyclohexane diisocyanate, methylcyclohexane diisocyanate, 2,2'-dimethyldicyclohexylmethane diisocyanate, dimer acid diisocyanate, 2,5-diisocyanatemethyl-bicyclo[2.2.1]-heptane, 2,6-diisocyanatemethyl-bicyclo[2.2.1]-heptane, 2-isocyanatemethyl-2-(3-isocyanatepropyl)-5-isocyanatemethyl-bicyclo[2.2.1]-heptane, 2-isocyanatemethyl-2-(3-isocyanatepropyl)-5-isocyanatemethyl-bicyclo[2.2.1]-heptane, 2-isocyanatemethyl-3-(3-isocyanatepropyl)-5-(2-isocyanateethyl)-bicyclo[2.2.1]-heptane, 2-isocyanatemethyl-3-(3-isocyanatepropyl)-6-(2-isocyanateethyl)-bicyclo[2.2.1]-heptane, 2-isocyanatemethyl-2-(3-isocyanatepropyl)-5-(2-isocyanateethyl)-bicyclo[2.2.1]-heptane, and 2-isocyanatemethyl-2-(3-isocyanatepropyl)-6-(2-isocyanateethyl)-bicyclo[2.2.1]-heptane.

[0066] Examples of polyisocyanates include modified isocyanates (such as urethane-modified, carbodiimide-modified, uretoimine-modified, biuret-modified, allophanate-modified, and isocyanurate-modified polyisocyanates).

[0067] (1.4.1.1.3) Chain extender A chain extender is used in the production of TPU (a). The chain extender is preferably a low-molecular-weight aliphatic, aromatic, heterocyclic, or alicyclic polyol having two or more hydroxyl groups per molecule. Examples of aliphatic polyols include ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, glycerin, and trimethylolpropane. Examples of aromatic, heterocyclic, or alicyclic polyols include paraxylene glycol, bis(2-hydroxyethyl)terephthalate, bis(2-hydroxyethyl)isophthalate, 1,4-bis(2-hydroxyethoxy)benzene, 1,3-bis(2-hydroxyethoxy)benzene, resorcinol, hydroquinone, 2,2'-bis(4-hydroxycyclohexyl)propane, 3,9-bis(1,1-dimethyl-2-hydroxyethyl)-2,4,8,10-tetraoxaspiro[5.5]undecane, 1,4-cyclohexanedimethanol, and 1,4-cyclohexanediol. These chain extenders may be used alone or in combination of two or more.

[0068] (1.4.1.1.4) Ethylene bisoleamide Ethylene bisoleamide is one of the components added to TPU (a). Ethylene bisoleamide is a compound obtained from ethylenediamine and oleic acid. The amount of ethylene bisoleamide added is usually 0.3 to 2.0% by mass, preferably 0.4 to 0.8% by mass, based on the TPU (a).

[0069] (1.4.1.1.5) Crosslinked organic fine particles Crosslinked organic fine particles are one of the components added to TPU (a). Crosslinked organic fine particles are fine particles that do not melt when TPU (a) is melt-spun. The average particle size of the crosslinked organic fine particles is usually 0.5 μm to 8 μm, preferably 1 μm to 4 μm.

[0070] The crosslinked organic fine particles can be obtained, for example, by polymerizing at least one specific compound and a crosslinking agent. Specific compounds include, for example: (meth)acrylates such as (meth)acrylic acid, methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, iso-propyl (meth)acrylate, n-butyl (meth)acrylate, iso-butyl (meth)acrylate, t-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, cyclohexyl (meth)acrylate, benzyl (meth)acrylate, hydroxyethyl (meth)acrylate, and hydroxypropyl (meth)acrylate; styrenes such as styrene, p-methylstyrene, vinyltoluene, and p-t-butylstyrene; maleimides such as N-phenylmaleimide, N-cyclohexylmaleimide, and N-benzylmaleimide; (meth)acrylamides such as (meth)acrylamide and N-methylol (meth)acrylamide; acrylonitriles such as (meth)acrylonitrile; and Examples of crosslinking agents include polyfunctional (meth)acrylates such as ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, and bishydroxyethyl bisphenol A di(meth)acrylate; radically polymerizable crosslinking agents such as divinyloxyethoxy (meth)acrylate, diallyl phthalate, allyl (meth)acrylate, and divinylbenzene; polyfunctional epoxy compounds such as bisphenol A diglycidyl ether, diethylene glycol diglycidyl ether, and neopentyl glycol diglycidyl ether; polyfunctional isocyanate compounds such as tolylene diisocyanate, xylylene diisocyanate, and isophorone diisocyanate; N-methylol melamine and N-methylol benzoguanamine. The amount of the crosslinked organic fine particles added is usually 0.3 to 2.0% by mass, preferably 0.4 to 2.0% by mass, based on the TPU (a).

[0071] (1.4.1.2) Other Thermoplastic Elastomers The stretchable fiber may or may not contain a known thermoplastic elastomer, as long as the object of the present disclosure is not impaired. Examples of thermoplastic elastomers include polystyrene-based elastomers, polyolefin-based elastomers, polyvinyl chloride-based elastomers, polyester-based elastomers, polyamide-based elastomers, and thermoplastic polyurethane elastomers other than the above TPU (a).

[0072] (1.4.1.3) Additives The stretchable fiber may or may not contain known additives, as long as the purpose of the present disclosure is not impaired. Examples of additives include antioxidants, heat stabilizers, weather stabilizers, antistatic agents, slip agents, anti-fogging agents, lubricants, dyes, pigments, natural oils, synthetic oils, and waxes.

[0073] Examples of additives include hindered phenol-based antioxidants, fatty acid metal salts, and polyhydric alcohol fatty acid esters. Examples of hindered phenol-based antioxidants include 2,6-di-t-butyl-4-methylphenol (BHT), pentaerythritol tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate] (manufactured by Ciba Corporation: trade name Irganox 1010), 6-(3,5-di-t-butyl-4-hydroxyphenyl)propionic acid alkyl ester, and 2,2'-oxamidobis[ethyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)]propionate. Examples of fatty acid metal salts include zinc stearate, calcium stearate, and calcium 1,2-hydroxystearate. Examples of polyhydric alcohol fatty acid esters include glycerin monostearate, glycerin distearate, pentaerythritol monostearate, pentaerythritol distearate, and pentaerythritol tristearate. These may be used alone or in combination of two or more.

[0074] (1.5) Extendable Fiber The extendable fiber includes TR(B).

[0075] The average fiber diameter of the extendable fiber is preferably 50 μm or less, more preferably 40 μm or less, and even more preferably 30 μm or less. The average fiber diameter of the extendable fiber is preferably 1 μm or more, more preferably 10 μm or more, and even more preferably 15 μm or more. The method for measuring the average fiber diameter of the extendable fiber is the same as the method for measuring the average fiber diameter of the stretchable fiber.

[0076] The extensible fibers may be long fibers or short fibers. From the viewpoint of 5% strength, the extensible fibers are preferably long fiber spunbond nonwoven fabrics. The cross-sectional shape of the extensible fibers is not particularly limited, and examples thereof include substantially circular, elliptical, and irregular cross sections.

[0077] The extendable fiber may be a composite fiber or a monocomponent fiber. The composite fiber preferably contains two or more thermoplastic resins as constituent components. Examples of composite fibers include sheath-core, side-by-side, islands-in-sea, and side-by-side types. The sheath-core composite fiber has only to have a core and a sheath, and may be either a concentric sheath-core type or an eccentric sheath-core type. The eccentric sheath-core composite fiber may have the core exposed on the surface, or the core may not be exposed on the surface. The islands-in-sea composite fiber has a sea phase and multiple island phases.

[0078] (1.5.1) Material The extensible fiber contains TR(B) or may consist of TR(B) alone. TR(B) may be a known thermoplastic resin.

[0079] (1.5.1.1) Thermoplastic resin (B) TR (B) is a polymer different from TPU (a). TR (B) is usually a crystalline polymer having a melting point (Tm) of 100°C or higher, or an amorphous polymer having a glass transition temperature of 100°C or higher. TR (B) is preferably a crystalline thermoplastic resin.

[0080] TR(B) is preferably a homopolymer or copolymer of an α-olefin (e.g., ethylene, propylene, 1-butene, 1-hexene, 4-methyl-1-pentene, 1-octene, etc.). Specific examples of TR(B) include polyolefins, polyesters (e.g., polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, etc.), polyamides (e.g., nylon-6, nylon-66, polymethaxylene adipamide, etc.), polyvinyl chloride, polyimides, ethylene-vinyl acetate copolymers, ethylene-vinyl acetate-vinyl alcohol copolymers, ethylene-(meth)acrylic acid copolymers, ethylene-acrylic acid ester-carbon monoxide copolymers, polyacrylonitrile, polycarbonate, polystyrene, ionomers, and mixtures thereof. Examples of polyolefins include polyethylene (e.g., high-pressure low-density polyethylene, linear low-density polyethylene (LLDPE), and high-density polyethylene (HDPE)), propylene polymers (e.g., propylene homopolymer, polypropylene random copolymer, ethylene-propylene random copolymer, and propylene-1-butene random copolymer), poly-1-butene, poly-4-methyl-1-pentene, and ethylene-1-butene random copolymer. Of these, polyethylene (e.g., high-pressure low-density polyethylene, linear low-density polyethylene, and high-density polyethylene), propylene polymers (e.g., propylene homopolymer and polypropylene random copolymer), polyethylene terephthalate, and polyamide are more preferred.

[0081] The thermoplastic resin (B) preferably contains at least one of polyethylene and a propylene-based polymer, and more preferably contains a propylene-based polymer and high-density polyethylene (HDPE). This improves the extensibility of the fibers and improves the stretch properties of the stretchable nonwoven fabric laminate. In particular, when the stretchable nonwoven fabric laminate includes an elastic SB layer and an extensible SB layer, multiple extensible fibers are continuously present in the thickness direction of the laminate. However, by using the TR (B) having excellent extensibility of the present disclosure in the extensible SB layer, deterioration of the stretch properties can be suppressed.

[0082] The propylene polymer may be a propylene homopolymer having a melting point (Tm) of 155°C or higher (preferably 157 to 165°C). The propylene polymer is preferably a copolymer of a propylene homopolymer having a melting point (Tm) of 155°C or higher (preferably 157 to 165°C) and a small amount of at least one α-olefin. Examples of the at least one α-olefin include ethylene, 1-butene, 1-pentene, 1-hexene, 1-octene, and 4-methyl-1-pentene.

[0083] The melt flow rate (MFR: ASTM D-1238, 230°C, load 2160 g) of the propylene polymer is not particularly limited as long as it can be melt-spun, but is usually 1 g / 10 min to 1000 g / 10 min, preferably 5 g / 10 min to 500 g / 10 min, and more preferably 10 g / 10 min to 100 g / 10 min. The ratio (Mw / Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) of the propylene polymer is usually 1.5 to 5.0. From the viewpoint of obtaining fibers with good spinnability and particularly excellent fiber strength, the ratio (Mw / Mn) is more preferably in the range of 1.5 to 3.0. Mw and Mn can be measured by a known method such as GPC (gel permeation chromatography).

[0084] The polyethylene in TR (B) preferably contains high-density polyethylene (HDPE). From the viewpoints of spinnability and stretchability, the content of high-density polyethylene (HDPE) is preferably 1 to 20% by mass, more preferably 2 to 15% by mass, and even more preferably 4 to 10% by mass, relative to 100% by mass of the total of the propylene polymer and the high-density polyethylene (HDPE).

[0085] The density of the high-density polyethylene (HDPE) added to the propylene polymer is not particularly limited, and is preferably 0.94 g / cm ３ ~0.97 g / cm ３ , more preferably 0.95 g / cm ３ ~0.97 g / cm ３ , more preferably 0.96 g / cm ３ ~0.97 g / cm３ From the viewpoint of improving the extensibility of the extensible fiber, the melt flow rate (MFR: ASTM D-1238, 190°C, load 2160 g) of the high density polyethylene (HDPE) is preferably 0.1 g / 10 min to 100 g / 10 min, more preferably 0.5 g / 10 min to 50 g / 10 min, and even more preferably 1 g / 10 min to 30 g / 10 min.

[0086] (1.5.1.2) Additives The extensible fiber may or may not contain known additives, as long as the purpose of the present disclosure is not impaired. Examples of additives include antioxidants, heat stabilizers, weather stabilizers, antistatic agents, slip agents, anti-fogging agents, lubricants, dyes, pigments, natural oils, synthetic oils, and waxes.

[0087] Examples of additives include hindered phenol-based antioxidants, fatty acid metal salts, and polyhydric alcohol fatty acid esters. Examples of hindered phenol-based antioxidants include 2,6-di-t-butyl-4-methylphenol (BHT), pentaerythritol tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate] (manufactured by Ciba Corporation: trade name Irganox 1010), 6-(3,5-di-t-butyl-4-hydroxyphenyl)propionic acid alkyl ester, and 2,2'-oxamidobis[ethyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)]propionate. Examples of fatty acid metal salts include zinc stearate, calcium stearate, and calcium 1,2-hydroxystearate. Examples of polyhydric alcohol fatty acid esters include glycerin monostearate, glycerin distearate, pentaerythritol monostearate, pentaerythritol distearate, and pentaerythritol tristearate. These may be used alone or in combination of two or more.

[0088] (1.6) Other Layers The stretchable nonwoven fabric may or may not have other layers depending on the application.

[0089] Examples of the other layer include knitted fabric, woven fabric, nonwoven fabric other than the elastic SB layer and the extensible SB layer, and film, etc. The method for further laminating the other layer on the nonwoven fabric (in other words, the method for further bonding the other layer to the nonwoven fabric) is not particularly limited, and examples include embossing, heat fusion (e.g., ultrasonic fusion, etc.), mechanical entanglement (e.g., needle punching, water jet, etc.), methods using adhesives (e.g., hot melt adhesives, urethane adhesives, etc.), and extrusion lamination.

[0090] Examples of nonwoven fabrics in which the elastic nonwoven fabric has an elastic SB layer and a nonwoven fabric other than the extensible SB layer 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. As long as the effects of the present disclosure are achieved, these nonwoven fabrics may be elastic or non-elastic nonwoven fabrics. "Non-elastic nonwoven fabrics" refer to fabrics that do not generate return stress after being stretched in the machine direction (MD) or cross direction (CD).

[0091] When imparting breathability to a stretchable nonwoven fabric containing other layers, it is preferable to use a breathable (i.e., moisture-permeable) film. Examples of breathable films include moisture-permeable films and porous films. Moisture-permeable films are made of thermoplastic elastomers (e.g., polyurethane elastomers, polyester elastomers, polyamide elastomers, etc.). Porous films are made by stretching a film made of a thermoplastic resin containing inorganic or organic fine particles to make it porous. Polyolefins are preferred as thermoplastic resins used for porous films. Examples of polyolefins include high-pressure low-density polyethylene, linear low-density polyethylene (LLDPE), high-density polyethylene, propylene-based polymers, polypropylene random copolymers, and combinations thereof. When it is not necessary to maintain the breathability and hydrophilicity of the stretchable nonwoven fabric, non-porous films can be used. Thermoplastic resin films (e.g., polyethylene, propylene-based polymers, and combinations thereof) may also be used as non-porous films.

[0092] (1.7) Elastic Member Stretchable nonwoven fabrics may be used in combination with elastic members (e.g., elastic threads, etc.). By placing a stretchable elastic member (e.g., elastic threads, etc.) 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. A stretch sheet combining a stretchable nonwoven fabric and elastic threads is 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 form of the elastic member include threads (e.g., rubber threads, etc.) and strings (e.g., flat rubber, etc.). Examples of cross-sectional shapes of the rubber thread 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. Examples of 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, or sewing, etc.).

[0093] (1.8) Biomass-Derived Propylene-Based Polymer The thermoplastic resin (e.g., propylene-based polymer, etc.) used in the present disclosure may be derived from a biomass-derived raw material. Because biomass-derived raw materials are carbon-neutral, the environmental impact of spunbond nonwoven fabric production can be reduced. Monomers serving as raw materials for biomass-derived thermoplastic resins can be obtained by cracking biomass naphtha or synthesizing them from biomass-derived ethylene. Biomass-derived thermoplastic resins can be obtained by polymerizing the biomass-derived monomers synthesized in this manner using a method similar to that used for conventionally known petroleum-derived thermoplastic resins. A thermoplastic resin polymer synthesized using a bio-derived monomer as a raw material is a biomass-derived thermoplastic polymer. The content of the bio-derived thermoplastic polymer in the raw material monomers can be greater than 0% by mass, 100% by mass, or less, relative to the total amount of raw material monomers. The "biomass content" indicates the content of biomass-derived carbon and is calculated by measuring radiocarbon (C14). Atmospheric carbon dioxide 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 approximately 105.5 pMC. It is also known that fossil fuels contain very little C14. Therefore, by measuring the proportion of C14 in the total carbon atoms in a polymer, the content of biomass-derived carbon in the raw material can be calculated. The thermoplastic polymer used as a raw material in the present disclosure may include a thermoplastic polymer obtained by recycling, i.e., a so-called recycled polymer. "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.

[0094] (1.9) Applications The applications of the stretchable nonwoven fabric of the present disclosure are not particularly limited, and include, for example, clothing materials (e.g., dustproof materials, supporters, interlinings, and adhesive interlinings), building materials (e.g., roofing materials and tufted carpet substrates), civil engineering goods (e.g., drain materials and filtration materials), vehicle materials (e.g., automobile interiors and automobile parts), hygiene materials (e.g., diapers, sanitary products, cosmetic sheets, first aid supplies, cleaning supplies, masks, poultices, bandages, protective clothing, surgical gowns, and coverings, etc.), interior (e.g., carpets, furniture components, fittings, wall coverings, and decorative items, etc.), bedding (e.g., futon bags, pillowcases, and sheets, etc.), agricultural materials (e.g., greenhouse sheets, weed control sheets, and seedbed sheets, etc.), leather (e.g., artificial leather base fabrics and synthetic leather base fabrics, etc.), daily necessities (e.g., storage items, packaging materials, cleaning supplies, and bags, etc.), and other industrial materials (e.g., industrial materials, electrical materials, and product base materials, etc.).

[0095] (1.10) Stretching The elastic nonwoven fabric of the present disclosure may be stretched. This improves the stretch properties of the elastic nonwoven fabric. 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. The stretching method may be a single-stage stretching method or a multi-stage stretching (multiple stretching). 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 (hereinafter also referred to as "Method A"). In Method A, the partially fused nonwoven fabric can be stretched by increasing the rotation speed of the nip rolls in the machine flow direction. Gear stretching can also be performed using the gear stretching device shown in Figure 1.

[0096] 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.

[0097] In the case of uniaxial stretching, it is preferable that either the stretching ratio in the machine direction (MD) or the stretching ratio in the cross direction (CD) satisfy the above-mentioned stretching ratio. In the case of biaxial stretching, it is preferable that at least one of the stretching ratio in the machine direction (MD) or the stretching ratio in the cross direction (CD) satisfy the above-mentioned stretching ratio.

[0098] By performing the drawing process at the draw ratio as described above, both the elastic fiber and the extensible fiber are drawn. The extensible fiber undergoes plastic deformation and is elongated according to the draw ratio (i.e., the extensible fiber becomes longer). After the stretchable nonwoven fabric is drawn, when the stress is released, the elastic fiber regains its elasticity, while the extensible fiber folds without regaining its elasticity, resulting in a bulky feel in the stretchable nonwoven fabric. Furthermore, the extensible fiber tends to become thinner. This is thought to improve the flexibility and feel of the stretchable nonwoven fabric, and to impart stretch-stopping properties to the stretchable nonwoven fabric.

[0099] (2) Textile Products The textile products of the present disclosure include the elastic nonwoven fabric of the present disclosure. The textile products are not particularly limited and can be used for the applications listed above. In particular, applications suitable for use as elastic members or stretchable members include hygiene materials (masks, diapers, sanitary products, individually wrapped sheets, cosmetic sheets, face masks, bandages, supports, antibacterial sheets, medical products using stretchable members on the cuffs or neck, antibacterial gloves, antibacterial hats, protective clothing, robot gowns, dustproof materials, medical drapes, machine table covers, and poultry covers), stretchable sheets, pillowcases, packaging materials, cleaning sheets, wallpaper, ceiling materials, floor materials, filtration materials, sound-absorbing materials, cushioning materials, furniture covers, weed control sheets, seedbed sheets, and fruit covers.

[0100] (3) Sanitary Materials The sanitary materials of the present disclosure include the stretchable nonwoven fabric of the present disclosure. Examples of the sanitary materials include, but are not limited to, masks, diapers, sanitary products, individually wrapped sheets, cosmetic sheets, face masks, bandages, supports, antibacterial sheets, medical products using stretchable materials on the cuffs or neck, antibacterial gloves, antibacterial hats, protective clothing, robot gowns, dustproof materials, medical drapes, machine table covers, and poultices.

[0101] 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."

[0102] [1] Measurement methods The physical properties of the stretchable nonwoven fabric laminates and the like were measured using the following methods. The measurement results are shown in Tables 1 to 3.

[0103] [1.1] Basis Weight Five test pieces measuring 200 mm (machine direction (MD)) x 50 mm (cross direction (CD)) and five test pieces measuring 200 mm (cross direction (CD)) x 50 mm (machine direction (MD)) were taken from the stretch nonwoven fabric laminate. The mass of each sample was measured. The average value obtained was converted to the unit area of ​​the test piece and rounded to the nearest tenth to obtain the "basis weight (gsm)".

[0104] [1.2] Thickness The thickness of the test piece on which the basis weight was measured at five points, the center and four corners, was measured using a thickness meter (manufactured by PEACOCK, product number "R1-250", measuring probe 25 mmφ) under a load of 7 g / m ２ The thickness was measured by this method for 10 samples of which the basis weight was measured, and the average value was taken as the "thickness (mm)."

[0105] [1.3] 5% Tensile Strength Five test pieces, each 200 mm long and 50 mm wide, were taken from the stretchable nonwoven fabric laminate. Using a tensile tester (manufactured by Intesco, product number "IM-201"), the test pieces were placed in the chuck so that they did not slacken and the load indicated by the tensile tester was 0.0 N. The test pieces were pulled in the machine direction (MD) with a chuck distance of 100 mm and a pulling speed of 100 mm / min. The load was read when the elongation of the test piece was 5%. The average of the five measurements was taken as the "5% tensile strength (N / 50 mm)" in the machine direction (MD).

[0106] The value obtained by dividing the 5% tensile strength in the machine direction (MD) by the basis weight of the stretchable nonwoven fabric laminate was defined as the "5% tensile strength per basis weight (N / 50 mm / gsm)" in the machine direction (MD).

[0107] [1.4] Tensile Strength The tensile strength was measured in accordance with JIS L 1913:2010. Five test pieces measuring 200 mm in length and 50 mm in width were taken from the elastic nonwoven fabric laminate. Using a tensile tester (manufactured by Intesco, product number "IM-201"), the test pieces were placed in the chuck so that they did not slacken and the load indicated by the tensile tester was 0.0 N. The test pieces were pulled in the machine direction (MD) with a chuck distance of 100 mm and a pulling speed of 100 mm / min. A load was applied to the test pieces until they broke. The strength of the test pieces at the maximum load was read. The average of the five measurements was taken as the "tensile strength (N / 50 mm)" in the machine direction (MD).

[0108] [1.5] Elongation The elongation was measured in accordance with JIS L 1913:2010. Five test pieces measuring 200 mm in length and 50 mm in width were taken from the elastic nonwoven fabric laminate. Using a tensile tester (manufactured by Intesco, product number "IM-201"), the test pieces were placed in the chuck so that they did not slacken and the load indicated by the tensile tester was 0.0 N. The test pieces were pulled in the machine direction (MD) at a chuck distance of 100 mm and a pulling speed of 100 mm / min. A load was applied to the test pieces until they broke. The elongation at the maximum load of the test piece was read. The average of the five measurements was taken as the "elongation (%)" in the machine direction (MD).

[0109] [1.6] Stretching Properties Five test pieces, each 200 mm long (MD) x 25 mm wide (CD), were taken from the stretchable nonwoven fabric laminate. Using a tensile tester (manufactured by Intesco, product number "IM-201"), the test pieces were placed in the chuck so that they would not slacken and the load indicated by the tensile tester was 0.0 N. The test pieces were stretched to an elongation of 100% at a chuck distance of 100 mm and a tensile speed of 300 mm / min, and then allowed to recover to their initial length at the same speed. This operation was repeated two times, and the value at the second cycle [stress at 50% elongation [S １ ] ÷ 50% recovery stress [S ２ ] (i.e., stress ratio (S １ / S ２ The average of the five values ​​was taken as the "stretch ratio." The smaller the stretch ratio, the better the stretch characteristics. An acceptable stretch ratio is 4.0 or less.

[0110] [1.7] Strength at 50% Width Reduction of Raw Fabric One test piece measuring 200 mm long x 50 mm wide was taken from the elastic nonwoven fabric laminate. Using a tensile tester (manufactured by Intesco, product number "IM-201"), the test piece was placed in the chuck so that it did not slacken and the load indicated by the tensile tester was 0.0 N. The test piece was pulled in the machine direction (MD) at a chuck distance of 100 mm and a pulling speed of 100 mm / min. At this time, the width of the center of the machine direction (MD) of the test piece (length in the cross direction (CD)) with the load applied to the test piece was recorded. The load was read when the width shrinkage rate reached 50%. The "width shrinkage rate" refers to the ratio of the width reduction due to elongation at the center of the machine direction (MD) of the test piece to the width of the unstretched test piece. The load when the width shrinkage rate was 50% was divided by the basis weight of the elastic nonwoven fabric laminate to obtain the "strength when width is reduced by 50% (N / 50 mm / gsm)." An acceptable strength when width is reduced by 50% is 0.60 N / 50 mm / gsm or more.

[0111] [1.8] Ease of Width Shrinkage of Gear-Processed Product The elastic nonwoven fabric laminate was subjected to gear-processing stretching in the machine direction (MD) at a stretch ratio of 160% to obtain a gear-stretched product. One test piece measuring 200 mm in length and 50 mm in width was taken from this gear-stretched product. Using a tensile tester (manufactured by Intesco, product number "IM-201"), the test piece was placed in the chuck so that it did not slacken and the load indicated by the tensile tester was 0.0 N. The test piece was pulled in the machine direction (MD) at a chuck distance of 100 mm and a pulling speed of 100 mm / min. The width of the center of the machine direction (MD) of the test piece (length in the cross direction (CD)) with the load applied to the test piece was recorded. The strength (hereinafter simply referred to as "strength") calculated by dividing the load applied to the test piece by the basis weight of the elastic nonwoven fabric laminate was plotted against the width of the center of the machine direction (MD) of the test piece. As a result, it was found that the obtained width decreased linearly when the strength was 0.1 N / 50 mm / gsm or more. Therefore, the width shrinkage rate was calculated, and the slope obtained from the load applied to the test piece and the width shrinkage rate was determined as the "ease of width shrinkage of the gear stretched product (N / 50 mm / gsm)" (hereinafter also referred to as "ease of width shrinkage"). The "width shrinkage rate" indicates the ratio of the width reduction due to stretching to the width of the unstretched test piece at the center of the machine direction (MD) of the test piece. The higher the value of the ease of width shrinkage, the more difficult it is to shrink the width. If the allowable ease of width shrinkage is 2.0 N / 50 mm / gsm or more, the stretch nonwoven fabric is easy to process. The ease of width shrinkage is preferably 2.5 N / 50 mm / gsm or more, and more preferably greater than 3.0 N / 50 mm / gsm.

[0112] [2] Preparation of Materials [2.1] Production Example of TPU (A) 71.7 parts by mass of polyester polyol having a number average molecular weight of 1932, 4.8 parts by mass of 1,4-butanediol (BD), 0.3 parts by mass of pentaerythritol tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate] (antioxidant), and 0.3 parts by mass of polycarbondiimide were mixed, and 22.9 parts by mass of 4,4'-diphenylmethane diisocyanate (MDI) was added thereto. The mixture was thoroughly mixed with high-speed stirring, and then reacted at 160°C for 1 hour. This reaction product was pulverized, and then 100 parts by mass of the pulverized product was mixed with 0.8 parts by mass of ethylene bisstearic acid amide, 0.5 parts by mass of triethylene glycol-bis-[3-3,5-di-t-butyl-4-hydroxyphenyl)propionate] (antioxidant), and 0.8 parts by mass of ethylene bisoleic acid amide (EOA), and the mixture was melt-kneaded and granulated in an extruder (set temperature: 210° C.). This produced a thermoplastic polyurethane elastomer (A-1) (hereinafter also referred to as "TPU (A-1)") as TPU (A).

[0113] [2.2] Production Example of TR (B) 94 parts by mass of propylene homopolymer and 6 parts by mass of high-density polyethylene were mixed. The MFR of the propylene homopolymer (measured in accordance with ASTM D1238 at a temperature of 230°C and a load of 2.16 kg) was 60 g / 10 min, and the density was 0.91 g / cm ３ The melting point was 160°C. The MFR of the high-density polyethylene (measured in accordance with ASTM D1238 at a temperature of 190°C and a load of 2.16 kg) was 5 g / 10 min, and the density was 0.97 g / cm ３ The melting point was 134° C. Thus, a thermoplastic resin composition (B-1) (hereinafter also referred to as “TR(B-1)”) was prepared as TR(B).

[0114] [3] Examples and Comparative Examples [3.1] Example 1 [3.1.1] Production of a Mixed Fiber Spunlaid Web TPU (A-1) and TR (B-1) were melted using two independent extruders. Then, using a spunbond nonwoven fabric molding machine equipped with a spinneret, melt spinning was performed by the spunbonding method under the following conditions: resin temperature and die temperature were both 205°C, cooling air temperature was 24°C, and stretching air velocity was 3,500 m / min. As a result, a first-layer spunlaid web was deposited on a screen. The first-layer spunlaid web was composed of a mixed long fiber composition containing a long fiber (A-1) (stretchable fiber) made of TPU (A-1) and a long fiber (B-1) (extensible fiber) made of TR (B-1).

[0115] The spinneret had a nozzle pattern in which discharge holes for TPU (A-1) and discharge holes for TR (B-1) were arranged alternately. The nozzle diameter for TPU (A-1) (long fiber (A-1)) was 0.75 mmφ. The nozzle diameter for TR (B-1) (long fiber (B-1)) was 0.6 mmφ. The nozzle pitch in the vertical direction was 8 mm. The nozzle pitch in the horizontal direction was 11 mm. The ratio of the number of nozzles (nozzles for long fiber (A-1) / nozzles for long fiber (B-1)) was 1 / 1.44. The throughput rate of a single hole for long fiber (A-1) was 0.90 g / hole / min. The throughput rate of a single hole for long fiber (B-1) was 0.71 g / hole / min.

[0116] Next, a second spunlaid web was deposited on the first spunlaid web in the same manner as in the formation of the first spunlaid web. The second spunlaid web was composed of a long fiber blend containing long fiber (A-1) (elastic fiber) and long fiber (B-1) (extensible fiber). This resulted in a web laminate (two layers).

[0117] [3.1.2] Production of a spunlaid web made from a thermoplastic resin composition TR (B-1) was melted using two independent extruders. Then, using a spunbond nonwoven fabric molding machine equipped with a spinneret, melt spinning was performed by the spunbonding method under the following conditions: resin temperature and die temperature were both 200°C, cooling air temperature was 24°C, and stretching air velocity was 4200 m / min. As a result, a third-layer spunlaid web was deposited on the web laminate (2 layers). The third-layer spunlaid web consisted of long fibers (B-1). As a result, a web laminate (3 layers) was obtained.

[0118] The nozzle pattern of the spinneret was the same as that of the spinneret used for producing the mixed fiber spunlaid web. The throughput rate of the continuous fiber (B-1) per hole was 0.66 g / hole / min.

[0119] [3.1.3] Embossing The web laminate (3 layers) was embossed. This resulted in a stretchable nonwoven fabric laminate. The stress at 50% elongation relative to the stress at 50% recovery of the stretchable nonwoven fabric laminate was 4.0 or less. The stress at 50% elongation relative to the stress at 50% recovery of each of the first layer (stretchable SB layer) and the second layer (stretchable SB layer) of the stretchable nonwoven fabric laminate was 4.0 or less. The elongation of the third layer (stretchable SB layer) of the stretchable nonwoven fabric laminate was 50% or more. When producing the stretchable nonwoven fabric laminate, the screen speed was adjusted so that the basis weight of the stretchable nonwoven fabric laminate was 35 gsm.

[0120] [3.2] Example 2 A stretchable nonwoven fabric laminate was produced in the same manner as in Example 1, except that the first and third layers were changed to spunlaid webs made of a blend of long fibers (A-1) and long fibers (B-1), and the second layer was changed to a spunlaid web made of long fiber (B-1).

[0121] [3.3] Example 3 A stretchable nonwoven fabric laminate was produced in the same manner as in Example 1, except that the single-hole output rate during production of the spunlaid web made of long fiber (B-1) was changed to 0.48 g / hole / min, and the stretching air velocity during production of the spunlaid web made of long fiber (B-1) was changed to 3100 m / min.

[0122] [3.4] Example 4 A stretchable nonwoven fabric laminate was produced in the same manner as in Example 1, except that the single-hole output rate during production of the spunlaid web made of long fiber (B-1) was changed to 0.57 g / hole / min and the stretching air velocity during production of the spunlaid web made of long fiber (B-1) was changed to 3600 m / min.

[0123] [3.5] Example 5 A stretchable nonwoven fabric laminate was produced in the same manner as in Example 1, except that the screen speed was changed so that the basis weight of the stretchable nonwoven fabric laminate would be 28 gsm.

[0124] [3.6] Example 6 A stretchable nonwoven fabric laminate was produced in the same manner as in Example 1, except that the screen speed was changed so that the basis weight of the stretchable nonwoven fabric laminate would be 41 gsm.

[0125] [3.7] Example 7 A stretchable nonwoven fabric laminate was produced in the same manner as in Example 1, except that the single-hole throughput rate of the long fiber (A-1) and the single-hole throughput rate of the long fiber (B-1) in producing a mixed fiber spunlaid web were changed to 0.97 g / hole / min and 0.67 g / hole / min, respectively.

[0126] [3.8] Example 8 A stretchable nonwoven fabric laminate was produced in the same manner as in Example 7, except that the screen speed was changed so that the basis weight of the stretchable nonwoven fabric laminate would be 70 gsm.

[0127] [3.9] Example 9 A stretchable nonwoven fabric laminate was produced in the same manner as in Example 7, except that the screen speed was changed so that the basis weight of the stretchable nonwoven fabric laminate would be 79 gsm.

[0128] [3.10] Comparative Example 1 A stretchable nonwoven fabric laminate was produced in the same manner as in Example 1, except that webs made of a blend of long fibers of long fiber (A-1) and long fiber (B-1) were laminated from the first layer to the third layer, and no spunlaid web made of long fiber (B-1) was laminated.

[0129] [3.11] Comparative Example 2 A stretchable nonwoven fabric laminate was produced in the same manner as in Comparative Example 1, except that the through-put rates of the long fiber (A-1) and the long fiber (B-1) were changed to 0.77 g / hole / min and 0.80 g / hole / min, respectively, during the production of a mixed fiber spunlaid web.

[0130] [3.12] Comparative Example 3 A stretchable nonwoven fabric laminate was produced in the same manner as in Comparative Example 1, except that the screen speed was changed so that the basis weight of the stretchable nonwoven fabric laminate would be 29 gsm.

[0131] [3.13] Comparative Example 4 A stretchable nonwoven fabric laminate was produced in the same manner as in Comparative Example 1, except that the single-hole throughput rates of the long fiber (A-1) and the long fiber (B-1) in producing a mixed fiber spunlaid web were changed to 0.97 g / hole / min and 0.67 g / hole / min, respectively, and the screen speed was changed so that the basis weight of the stretchable nonwoven fabric laminate would be 71 gsm.

[0132] [3.14] Comparative Example 5 A stretchable nonwoven fabric laminate was produced in the same manner as in Comparative Example 4, except that the screen speed was changed so that the basis weight of the stretchable nonwoven fabric laminate would be 80 gsm.

[0133]

[0134]

[0135]

[0136] In Tables 1 to 3, "Elastic SB" refers to an elastic spunbonded nonwoven fabric layer. "Extensible SB" refers to an extensible spunbonded nonwoven fabric layer.

[0137] In Comparative Examples 1 to 5, the 5% tensile strength per unit area weight of the stretchable nonwoven fabric laminate was not 0.20 [N / 50 mm / gsm] or more. Therefore, the strength (N / 50 mm / gsm) at 50% reduction in width of Comparative Examples 1 to 5 was not 0.60 N / 50 mm / gsm or more. These results demonstrate that the stretchable nonwoven fabric laminates of Comparative Examples 1 to 5 are not "stretchable nonwoven fabrics with excellent stretch properties and reduced width shrinkage."

[0138] In Examples 1 to 9, the stretchable nonwoven fabric laminate contained a stretchable fiber (long fiber (A-1)) and an extensible fiber (long fiber (B-1)). The TPU content was 25% to 39% by mass based on the total amount of the stretchable nonwoven fabric laminate. The 5% tensile strength per unit area of ​​the stretchable nonwoven fabric laminate was 0.20 [N / 50 mm / gsm] or more. Therefore, the stretch ratios of Examples 1 to 9 were 4.0 or less. The strength (N / 50 mm / gsm) at 50% width reduction of Examples 1 to 9 was 0.60 N / 50 mm / gsm or more. These results demonstrate that the stretchable nonwoven fabric laminates of Examples 1 to 9, although having a lower TPU content than the comparative example, were "stretchable nonwoven fabrics with excellent stretch properties and reduced width shrinkage."

[0139] The disclosure of Japanese Patent Application No. 2024-035390, filed on March 7, 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 stretchable nonwoven fabric comprising: stretchable fibers containing a thermoplastic polyurethane elastomer (A); and extensible fibers containing a thermoplastic resin (B) different from said thermoplastic polyurethane elastomer (A), wherein the content of said thermoplastic polyurethane elastomer (A) is 25% to 39% by mass relative to the total amount of the stretchable nonwoven fabric, and wherein the 5% tensile strength per basis weight of the stretchable nonwoven fabric is 0.20 [N / 50 mm / gsm] or more, and said 5% tensile strength indicates the load required to pull the stretchable nonwoven fabric in the machine direction (MD) of the stretchable nonwoven fabric until an elongation of 5% is achieved.

2. The elastic nonwoven fabric of claim 1, comprising: at least one elastic spunbond nonwoven layer comprising the elastic fibers; and at least one extensible spunbond nonwoven layer comprising the extensible fibers.

3. The stretchable nonwoven fabric according to claim 2, wherein the ratio of the basis weight of the extensible spunbonded nonwoven fabric layer to the basis weight of the stretchable nonwoven fabric is 15% to 35%.

4. The stretchable nonwoven fabric according to claim 2 or 3, wherein the stretchable spunbond nonwoven fabric layer is a surface layer.

5. The stretchable nonwoven fabric according to claim 2 or 3, wherein the extensible spunbond nonwoven fabric layer is included in an intermediate layer.

6. The stretchable nonwoven fabric according to any one of claims 1 to 5, wherein the thermoplastic resin (B) includes at least one of polyethylene and a propylene-based polymer.

7. The stretchable nonwoven fabric according to any one of claims 1 to 6, wherein the basis weight of the stretchable nonwoven fabric is 10 gsm to 120 gsm.

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

9. A hygienic material comprising the stretchable nonwoven fabric according to any one of claims 1 to 7.