Manufacturing method of laminated nonwoven fabric

Abstract

To provide a method for manufacturing laminated nonwoven fabrics with excellent handling properties. [Solution] The method involves creating a laminated web by laminating a fiber web B containing staple fibers with a fiber length of 20 mm to 100 mm onto both surfaces of a fiber web A containing short fibers with a fiber length of less than 20 mm, and spraying a water stream onto one or both surfaces of the laminated web, wherein the fiber web A has a specific tensile strength ID in the MD direction, which is determined according to JIS P 8113:2006 Paper and cardboard - Test methods for tensile properties - Part 2: Constant-speed stretching method, when the longitudinal direction of the fiber web A is the MD direction and the width direction is the CD direction. MD and the specific tensile strength ID in the CD direction CD However, the present invention provides a method for manufacturing a laminated nonwoven fabric that satisfies at least one of the following (A1) and (A2). (A1) 5.0 N·m / g ≤ ID MD ≤19.0 N·m / g (A2) 1.0 N·m / g ≤ ID CD ≤5.0 N·m / g

Description

[Technical Field]

[0001] This disclosure relates to a method for manufacturing laminated nonwoven fabrics. [Background technology]

[0002] Nonwoven fabrics impregnated with liquid are widely used, for example, to cover the skin of humans or animals to impart a specific substance to the skin, or as wipers to wipe away dirt from people's bodies or objects. Various compositions of nonwoven fabrics for liquid impregnation have been proposed and put into practical use.

[0003] For example, Patent Document 1 discloses a spunlace nonwoven fabric with a three-layer structure in which tissue paper having a colored pattern formed on at least one side is interposed as a middle layer between the surface layer and the back layer, wherein the spunlace nonwoven fabric is manufactured by inserting tissue paper having a colored pattern formed on at least one side into the middle layer during the manufacturing process of the spunlace nonwoven fabric and spraying it with a high-pressure water jet (however, heat fusion between fibers is not performed), and the spunlace nonwoven fabric has a tensile strength of 35 N / 50 mm or more in the MD direction, a tensile strength of 5 N / 50 mm or more in the CD direction, a tensile elongation of 5 to 60% in the MD direction, and a tensile elongation of 50 to 150% in the CD direction. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Patent No. 4545414 [Overview of the project] [Problems that the invention aims to solve]

[0005] This disclosure provides a method for manufacturing a laminated nonwoven fabric with excellent handling properties. [Means for solving the problem]

[0006] This disclosure is, To create a laminated web by laminating a fiber web B containing staple fibers with a fiber length of 20 mm to 100 mm onto both surfaces of a fiber web A containing short fibers with a fiber length of less than 20 mm, and, This includes spraying a water stream onto one or both surfaces of the laminated web, When the fiber web A has its longitudinal direction as the MD direction and its width direction as the CD direction, JIS P 8113:2006 Paper and cardboard - Test methods for tensile properties - Part 2: Specific tensile strength (ID) in the MD direction determined according to the constant-rate elongation method. MD and the specific tensile strength ID in the CD direction CD However, the present invention provides a method for manufacturing a laminated nonwoven fabric that satisfies at least one of the following (A1) and (A2). (A1) 5.0 N·m / g ≤ ID MD ≤19.0 N·m / g (A2) 1.0 N·m / g ≤ ID CD ≤5.0 N·m / g

[0007] This disclosure also, To create a laminated web by laminating a fiber web B containing staple fibers with a fiber length of 20 mm to 100 mm onto both surfaces of a fiber web A containing short fibers with a fiber length of less than 20 mm, and, This includes spraying a water stream onto one or both surfaces of the laminated web, When the fiber web A has its longitudinal direction as the MD direction and its width direction as the CD direction, The aforementioned fiber web A is The specific tensile strength (N·m / g) is obtained by dividing the stress (N / m) in the CD direction when the paper is stretched 2% or 3% from the zero point at standard time by the basis weight, as determined in accordance with JIS P 8113:2006 Paper and cardboard - Test methods for tensile properties - Part 2: Constant-rate stretching method, and is then given the ID. 2-CD ID 3-CD The specific tensile strength (N·m / g) is calculated by dividing the stress (N / m) in the CD direction when the material is stretched 3% from the zero point in a wet state, as determined in accordance with JIS P 8135:1998 Paper and cardboard - Wet tensile strength test method, by the basis weight. 3-CDin such a case, a method for producing a laminated nonwoven fabric is provided, which satisfies at least one selected from the following (B1) to (B3). (B1) 0.5N·m / g≦ID 2-CD ≦3.8N·m / g (B2) 1.0N·m / g≦ID 3-CD ≦4.5N·m / g (B3) 0.33N·m / g≦IW 3-CD ≦0.75N·m / g

Effects of the Invention

[0008] According to the present disclosure, a method for producing a laminated nonwoven fabric with excellent handleability is provided.

Modes for Carrying Out the Invention

[0009] If a nonwoven fabric used in a wet state, such as a face mask, is too soft, it is difficult to take out from the package and also difficult to spread. On the other hand, if the nonwoven fabric is rigid or has low elongation, it is difficult to adhere to the skin or the like. The tensile properties of the nonwoven fabric are greatly involved in facilitating taking out and spreading the nonwoven fabric from the package, as well as making it easy to adhere to the skin.

[0010] It has been found that the tensile properties of a laminated nonwoven fabric having at least a three-layer structure that includes short fibers as an intermediate layer and is produced by hydroentanglement treatment are affected by the physical properties of the fiber web (fiber web A described later) forming the intermediate layer, particularly the breaking stress or the stress at low elongation.

[0011] In the first embodiment, the fiber web A is specified by the breaking stress (tensile strength) in its CD direction or MD direction, and in the second embodiment, the fiber web A is specified by its stress at low elongation.

[0012] Hereinafter, "handleability" means that the laminated nonwoven fabric in a wet state is easy to take out and spread from a package, and is easy to adhere to the skin.

[0013] The laminated nonwoven fabric of this disclosure exhibits excellent performance even under standard conditions (dry state). For example, when used as a dry wiper, it has appropriate strength, resulting in a pleasant user experience, and it also offers excellent handling when impregnating with liquid.

[0014] First Embodiment [Method for manufacturing laminated nonwoven fabric] The laminated nonwoven fabric of this embodiment is manufactured by a method that includes creating a laminated web by laminating a fiber web B containing staple fibers with a fiber length of 20 mm to 100 mm onto both surfaces of a fiber web A containing short fibers with a fiber length of less than 20 mm, and spraying a stream of water onto one or both surfaces of the laminated web.

[0015] Fiber web A is, JIS P 8113:2006 Paper and cardboard - Test methods for tensile properties - Part 2: Specific tensile strength (ID) in the MD direction determined according to the constant-rate elongation method. MD and ratio tensile strength ID in the CD direction CD However, it satisfies at least one of the following (A1) and (A2).

[0016] (A1) 5.0 N·m / g ≤ ID MD ≤19.0 N·m / g (A2) 1.0 N·m / g ≤ ID CD ≤5.0 N·m / g

[0017] In this embodiment, the specific tensile strength of fiber web A, obtained by dividing the tensile strength in the MD or CD direction by the basis weight, is within a certain range. Therefore, it is considered that the entanglement of the short fibers constituting fiber web A is easily undone when entangled in water flow. This improves the flexibility of the laminated nonwoven fabric. In addition, the short fibers become more mobile and can entangle with the fibers constituting fiber web B, thereby imparting appropriate elongation to the laminated nonwoven fabric. In other words, if the specific tensile strength at standard or wet conditions is within a certain range, handling is improved.

[0018] In addition, the processability of the laminated nonwoven fabric is also improved. Processability refers to how easy it is to cut the laminated nonwoven fabric into the shape of a product, make incisions, or apply desired printing. If the laminated nonwoven fabric is too soft, it may wrinkle and shift position, while if it is too rigid, cutting and other operations become difficult.

[0019] The fiber web A may satisfy both (A1) and (A2) above. This further improves handling and reduces discomfort when in close contact.

[0020] (A1) Specific tensile strength ID in the MD direction MD It may satisfy any of the following conditions (A1a) to (A1c). The unit (N·m / g) is omitted. (A1a) 5.5 ≤ ID MD ≤18.0 (A1b) 6.0 ≤ ID MD ≤17.0 (A1c)6.5≦ID MD ≤16.0

[0021] (A2) Specific tensile strength ID in the CD direction CD It may satisfy any of the following conditions (A2a) to (A2c). The unit (N·m / g) is omitted. (A2a) 1.1 ≤ ID CD ≤4.8 (A2b) 1.3 ≤ ID CD ≤4.5 (A2c) 1.8 ≤ ID CD ≤4.0

[0022] Fiber web A may satisfy both (A1a) and (A2a) above. Fiber web A may satisfy both (A1b) and (A2b) above. Fiber web A may satisfy both (A1c) and (A2c) above.

[0023] Furthermore, fiber web A is JIS P 8135:1998 Paper and cardboard - Wet tensile strength SW in the MD direction as measured in accordance with the wet tensile strength test method. MD and wet tensile strength SW in the CD direction CDEach is weighed (g / m²). 2 Specific wet tensile strength IW divided by ) MD and specific wet tensile strength IW CD However, it may satisfy at least one of the following (A3) and (A4). This further improves handling.

[0024] (A3) 1.0 N·m / g ≤ IW MD ≤4.1 N·m / g (A4) 0.3 N·m / g ≤ IW CD ≤1.2 N·m / g

[0025] The fiber web A may satisfy both (A3) and (A4) above. This further improves handling and reduces discomfort when in close contact.

[0026] (A3) Specific wet tensile strength IW in the MD direction MD It may satisfy any of the following conditions (A3a) to (A3c). The unit (N·m / g) is omitted. (A3a) 1.5 ≤ IW MD ≤4.0 (A3b) 2.13 ≤ IW MD ≤3.9 (A3c)2.15≦IW MD ≤3.8

[0027] (A4) Specific wet tensile strength IW in the CD direction CD It may satisfy any of the following conditions (A4a) to (A4c). The unit (N·m / g) is omitted. (A4a) 0.50 ≤ IW CD ≤1.0 (A4b) 0.53 ≤ IW CD ≤0.9 (A4c)0.56≦IW CD ≤0.85

[0028] Fiber web A may satisfy both (A3a) and (A4a) above. Fiber web A may satisfy both (A3b) and (A4b) above. Fiber web A may satisfy both (A3c) and (A4c) above.

[0029] Furthermore, fiber web A is The stress (N / m) in the MD direction when the paper is stretched by 1%, 2%, and 3% from the zero point at standard time, as determined in accordance with JIS P 8113:2006 Paper and cardboard - Test methods for tensile properties - Part 2: Constant-rate stretching method, is expressed as SD. 1-MD SD 2-MD SD 3-MD The stresses (N / m) in the MD direction when the material is stretched by 1%, 2%, and 3% from the zero point in a wet state, as determined in accordance with JIS P 8135:1998 Paper and cardboard - Wet tensile strength test method, are SW, respectively. 1-MD SW 2-MD SW 3-MD In this case, at least one of the following (C1) to (C6) may be satisfied. This further improves operability.

[0030] (C1) 5.0 N / m ≤ SD 1-MD ≤30.0 N / m (C2) 10.0 N / m ≤ SD 2-MD ≤50.0 N / m (C3) 15.0 N / m ≤ SD 3-MD ≤70.0 N / m (C4) 3.0 N / m ≤ SW 1-MD ≤10.0 N / m (C5) 4.0 N / m ≤ SW 2-MD ≤20.0 N / m (C6) 4.5 N / m ≤ SW 3-MD ≤30.0 N / m

[0031] Fiber web A may satisfy all of the above conditions (C1) to (C6).

[0032] (C1) Stress SD at 1% elongation in the MD direction under standard conditions 1-MD It may satisfy any of the following conditions (C1a) to (C1c). The unit (N / m) is omitted. (C1a) 6.0 ≤ SD 1-MD ≤27.0 (C1b) 7.0 ≤ SD 1-MD ≤25.0 (C1c)8.0≦SD1-MD ≤23.0

[0033] (C2) Stress SD at 2% tensile strength in the MD direction under standard conditions 2-MD It may satisfy any of the following conditions (C2a) to (C2c). The unit (N / m) is omitted. (C2a) 11.0 ≤ SD 2-MD ≤48.0 (C2b) 13.0 ≤ SD 2-MD ≤46.0 (C2c)15.0≦SD 2-MD ≤45.0

[0034] (C3) Stress SD at 3% extension in the MD direction under standard conditions 3-MD It may satisfy any of the following conditions (C3a) to (C3c). The unit (N / m) is omitted. (C3a) 16.0 ≤ SD 3-MD ≤65.0 (C3b) 17.0 ≤ SD 3-MD ≤60.0 (C3c)20.0≦SD 3-MD ≤55.0

[0035] (C4) Stress SW at 1% elongation in wet conditions in the MD direction 1-MD It may satisfy any of the following conditions (C4a) to (C4c). The unit (N / m) is omitted. (C4a) 3.5 ≤ SD 1-MD ≤9.5 (C4b) 4.0 ≤ SD 1-MD ≤9.0 (C4c)4.5≦SD 1-MD ≤8.5

[0036] (C5) Stress SW at 2% elongation in wet conditions in the MD direction 2-MD It may satisfy any of the following conditions (C5a) to (C5c). The unit (N / m) is omitted. (C5a) 4.5 ≤ SW 2-MD ≤19.0 (C5b) 5.0 ≤ SW 2-MD ≤17.0 (C5c)5.5≦SW 2-MD ≤15.0

[0037] (C6) Stress SW at 3% elongation in wet conditions in the MD direction 3-MD It may satisfy any of the following conditions (C6a) to (C6c). The unit (N / m) is omitted. (C6a) 5.0 ≤ SW 3-MD ≤28.0 (C6b) 5.5 ≤ SW 3-MD ≤25.0 (C6c)6.0≦SW 3-MD ≤23.0

[0038] Fiber web A may satisfy all of the above (C1a), (C2a), (C3a), (C4a), (C5a), and (C6a). Fiber web A may satisfy all of the above (C1b), (C2b), (C3b), (C4b), (C5b), and (C6b). Fiber web A may satisfy all of the above (C1c), (C2c), (C3c), (C4c), (C5c), and (C6c).

[0039] Furthermore, fiber web A is The stress (N / m) in the CD direction when the paper is stretched by 1%, 2%, and 3% from the zero point at standard time, as determined in accordance with JIS P 8113:2006 Paper and cardboard - Test methods for tensile properties - Part 2: Constant-rate stretching method, is expressed as SD. 1-CD SD 2-CD SD 3-CD The stresses (N / m) in the CD direction when the material is stretched by 1%, 2%, and 3% from the zero point in a wet state, as determined in accordance with JIS P 8135:1998 Paper and cardboard - Wet tensile strength test method, are SW, respectively. 1-CD SW 2-CD SW 3-CD In this case, at least one of the following (CW1) to (CW6) may be satisfied. This further improves handling.

[0040] (CW1) 5.0 N / m ≤ SD 1-CD ≤37.0 N / m (CW2) 10.0 N / m ≤ SD 2-CD ≤65.0 N / m (CW3)15.0N / m≦SD 3-CD ≦80.0N / m (CW4)6.0N / m≦SW 1-CD ≦10.0N / m (CW5)7.0N / m≦SW 2-CD ≦20.0N / m (CW6)5.5N / m≦SW 3-CD ≦25.0N / m

[0041] The fiber web A may satisfy all of the above (CW1) to (CW6).

[0042] (CW1) Stress SD at 1% elongation under standard conditions in the CD direction 1-MD may satisfy any one of the following (CW1a) to (CW1c). The unit (N / m) is omitted. (CW1a)10.0≦SD 1-MD ≦35.0 (CW1b)13.0≦SD 1-MD ≦33.0 (CW1c)15.0≦SD 1-MD ≦32.0

[0043] (CW2) Stress SD at 2% elongation under standard conditions in the CD direction 2-CD may satisfy any one of the following (CW2a) to (CW2c). The unit (N / m) is omitted. (CW2a)15.0≦SD 2-CD ≦62.0 (CW2b)20.0≦SD 2-CD ≦58.0 (CW2c)28.0≦SD 2-CD ≦55.0

[0044] (CW3) Stress SD at 3% elongation under standard conditions in the CD direction 3-CD may satisfy any one of the following (CW3a) to (CW3c). The unit (N / m) is omitted. (CW3a)18.0≦SD 3-CD ≦70.0 (CW3b)20.0≦SD 3-CD ≦65.0 (CW3c)22.0≦SD3-CD ≦60.0

[0045] (CW4) Stress SW at 1% elongation in the CD direction under wet conditions 1-CD may satisfy any one of the following (CW4a) to (CW4c). The unit (N / m) is omitted. (CW4a)6.2≦SW 1-CD ≦9.8 (CW4b)6.3≦SW 1-CD ≦9.7 (CW4c)6.5≦SW 1-CD ≦9.6

[0046] (CW5) Stress SW at 2% elongation in the CD direction under wet conditions 2-CD may satisfy any one of the following (CW5a) to (CW5c). The unit (N / m) is omitted. (CW5a)7.0≦SW 2-CD ≦20.0 (CW5b)7.5≦SW 2-CD ≦17.0 (CW5c)8.0≦SW 2-CD ≦15.0

[0047] (CW6) Stress SW at 3% elongation in the CD direction under wet conditions 3-CD may satisfy any one of the following (CW6a) to (CW6c). The unit (N / m) is omitted. (CW6a)5.0≦SW 3-CD ≦28.0 (CW6b)5.5≦SW 3-CD ≦25.0 (CW6c)6.0≦SW 3-CD ≦15.0

[0048] The fiber web A may satisfy all of the above (CW1a), (CW2a), (CW3a), (CW4a), (CW5a) and (CW6a). The fiber web A may satisfy all of the above (CW1b), (CW2b), (CW3b), (CW4b), (CW5b) and (CW6b). The fiber web A may satisfy all of the above (CW1c), (CW2c), (CW3c), (CW4c), (CW5c) and (CW6c).

[0049] Furthermore, fiber web A is JIS P 8135:1998 Paper and cardboard - Wet tensile strength SW in the MD direction as measured in accordance with the wet tensile strength test method. MD and wet tensile strength SW in the CD direction CD However, it may satisfy at least one of the following (D1) and (D2). This further improves handling.

[0050] (D1) 35.5 N / m ≤ SW MD ≤80.0 N / m (D2) 8.0 N / m ≤ SW CD ≤30.0 N / m

[0051] Fiber web A may satisfy both (D1) and (D2) above.

[0052] (D1) Wet tensile strength SW in the MD direction MD It may satisfy any of the following conditions (D1a) to (D1c). The unit (N / m) is omitted. (D1a) 35.8 ≤ SW MD ≤78.0 (D1b) 36.0 ≤ SW MD ≤75.0 (D1c)36.2≦SW MD ≤70.0

[0053] (D2) Wet tensile strength SW in the CD direction CD It may satisfy any of the following conditions (D2a) to (D2c). The unit (N / m) is omitted. (D2a) 8.3 ≤ SW CD ≤28.0 (D2b) 8.6 ≤ SW CD ≤25.0 (D2c)9.0≦SW CD ≤21.0

[0054] Fiber web A may satisfy both (D1a) and (D2a) above. Fiber web A may satisfy both (D1b) and (D2b) above. Fiber web A may satisfy both (D1c) and (D2c) above.

[0055] Furthermore, fiber web A is The residual wet tensile strength RW in the MD direction, as determined in accordance with JIS P 8135:1998 Paper and cardboard - Wet tensile strength test method. MD and the wet tensile strength retention rate RW in the CD direction. CD However, it may satisfy at least one of the following (E1) and (E2). This makes it less likely for fiber web A to break even when tension is applied during the manufacturing process, and may also make it easier for fiber web B to entangle with water flow. In addition, the flexibility of the laminated nonwoven fabric in the CD direction when wet may be improved.

[0056] (E1) 15.0% ≤ RW MD ≤40.0% (E2)10.0%≦RW CD ≤40.0%

[0057] The fiber web A may satisfy both (E1) and (E2) above.

[0058] (E1) Wet tensile strength residue in the MD direction RW MD It may satisfy any of the following conditions (E1a) to (E1c). The unit (%) is omitted. (E1a) 15.5 ≤ RW MD ≤39.0 (E1b) 16.0 ≤ RW MD ≤37.0 (E1c)18.5≦RW MD ≤35.5

[0059] (E2) Residual wet tensile strength in the CD direction RW CD It may satisfy any of the following conditions (E2a) to (E2c). The unit (%) is omitted. (E2a)12.0≦RW CD ≤39.0 (E2b)13.0≦RW CD ≤37.0 (E2c)14.0≦RW CD ≤35.0

[0060] Fiber web A may satisfy both (E1a) and (E2a) above. Fiber web A may satisfy both (E1b) and (E2b) above. Fiber web A may satisfy both (E1c) and (E2c) above.

[0061] Furthermore, fiber web A is The air permeability measured according to JIS P 8117:2009 Paper and cardboard - Test methods for air permeability and air permeability resistance (intermediate range) - Gurley method may be 0.05 seconds / 300 ml or more and 1.0 seconds / 300 ml or less. This makes it less likely for wrinkles to form in fiber web A during water entanglement pretreatment (wetting and suction), improves adhesion with fiber web B, and improves the form of the laminated nonwoven fabric.

[0062] The above air permeability may be 0.06 seconds / 300ml or more, 0.07 seconds / 300ml or more, or 0.08 seconds / 300ml or more. The above air permeability may be 0.8 seconds / 300ml or less, 0.7 seconds / 300ml or less, or 0.6 seconds / 300ml or less. The above air permeability may be 0.06 to 0.8 seconds / 300ml, 0.07 to 0.7 seconds / 300ml, or 0.08 to 0.6 seconds / 300ml.

[0063] The fiber web used in the manufacturing method of the laminated nonwoven fabric of this embodiment will be described in detail below.

[0064] [Short fibers] The fiber web A of this embodiment includes short fibers with a fiber length of less than 20 mm. The fiber length of the short fibers may be, for example, 0.7 mm or more and 20 mm or less, particularly 0.8 mm or more and 15 mm or less, and more particularly 0.9 mm or more and 10 mm or less. If the short fibers are chemical fibers or synthetic fibers such as rayon, the fiber length is measured according to JIS L 1015:2010 (Method D).

[0065] The short fibers may be synthetic fibers, cellulosic fibers, natural fibers other than cellulosic fibers, or inorganic fibers.

[0066] Examples of cellulose fibers include the following: (1) Natural fibers derived from plants such as cotton, flax, linen, ramie, jute, banana, bamboo, kenaf, ginger lily, hemp, and kapok; (2) Rayon and polynosic obtained by the viscose process, cupro obtained by the copper ammonia process, and solvent-spun cellulose fibers such as Tencel® and lyocell obtained by the solvent spinning process, as well as other regenerated fibers; (3) Cellulose fibers obtained by melt spinning; (4) Semi-synthetic fibers such as acetate fibers; and (5) Pulps such as mechanical pulp, recycled pulp and chemical pulp

[0067] The fineness of the cellulose fiber is not particularly limited. The fineness of the cellulose fiber may be between 0.2 dtex and 22.0 dtex. The fineness of the cellulose fiber may be 0.3 dtex or more, 0.8 dtex or more, or 1.0 dtex or more. The fineness of the cellulose fiber may be 14.0 dtex or less, 10.0 dtex or less, 6.7 dtex or less, or 4.4 dtex or less. In one embodiment, the fineness of the cellulose fiber is between 0.6 dtex and 4.4 dtex. Since it is difficult to adjust the fineness of natural fibers, cellulose fibers with fineness outside the above range may be used. In the case of natural fibers, the fineness may be measured by a method similar to the microneya method described in JIS L 1019:2006 7.4.1 Measurement of fineness by ISO method. Furthermore, in the case of regenerated fibers, measurement may be performed using a method similar to the vibration method described in JIS L 1015:2010 8.5 ISO method (reference method) for measuring fineness.

[0068] Cellulose fibers may have a fiber diameter of 5.0 μm or more and 23.0 μm or less. The fiber diameter of cellulose fibers may be 6.0 μm or more, 7.0 μm or more, or 8.0 μm or more. The fiber diameter of cellulose fibers may be 22.0 μm or less, 21.0 μm or less, or 20.0 μm or less. The fiber diameter of cellulose fibers is determined, for example, by observing the fabric with an electron microscope at approximately 400x magnification and determining the diameter of the fiber cross-section. If the fiber cross-section is not circular, the fiber diameter is the average value of the length of the major axis of the fiber cross-section and the maximum length of the distance between two points on the fiber cross-section perpendicular to the major axis.

[0069] Synthetic fibers are usually formed from thermoplastic resins. The thermoplastic resin is not particularly limited. Examples of thermoplastic resins include aromatic polyester resins such as polyethylene terephthalate, polybutylene terephthalate, polytrimethylene terephthalate, and polyethylene naphthalate; aliphatic polyester resins such as polylactic acid, polyglycolic acid, poly(β-hydroxybutyric acid), poly(β-hydroxyacetic acid-co-β-hydroxyvaleric acid), poly-β-propiolactone, poly-ε-caprolactone, polyethylene succinate, polybutylene succinate and its copolymers; and aliphatic aromatic polyester resins obtained by copolymerizing aromatic polyesters and aliphatic polyesters (e.g., butylene adipate-co Polyester resins such as terephthalate; polyolefin resins such as polypropylene, polyethylene (including high-density polyethylene, low-density polyethylene, linear low-density polyethylene, etc.), polybutene-1, propylene copolymers (including propylene-ethylene copolymers, propylene-butene-1-ethylene copolymers), ethylene-vinyl alcohol copolymers, and ethylene-vinyl acetate copolymers; polyamide resins such as nylon 6, nylon 12, and nylon 66; acrylic resins; polyurethane resins; engineering plastics such as polycarbonate, polyacetal, polystyrene, and cyclic polyolefins, as well as their elastomers.

[0070] Synthetic fibers may be single fibers whose fiber cross-section consists of a single component (also called a "single section"), and / or composite fibers whose fiber cross-section consists of multiple components (also called "sections"). Composite fibers may be, for example, concentric or eccentric core-sheath type composite fibers, sea-island type composite fibers, side-by-side type composite fibers, or segmented type composite fibers. The fiber cross-section may be circular or non-circular, and non-circular shapes include elliptical, Y-shaped, X-shaped, grid-shaped, multi-lobed, polygonal, and star-shaped. Synthetic fibers may also have a hollow cross-section. In both the case of single fibers and composite fibers, each section constituting the fiber may be made of one type of resin, or a mixture of two or more types of resins.

[0071] The fineness of synthetic fibers is, for example, 0.4 dtex or more and 4.0 dtex or less. The fineness of synthetic fibers may be 0.5 dtex or more, 0.6 dtex or more, 0.9 dtex or more, or 1.1 dtex or more. The fineness of synthetic fibers may be 4.0 dtex or less, 2.6 dtex or less, 2.4 dtex or less, or 2.2 dtex or less. The method for measuring fineness is as previously explained in relation to cellulosic fibers.

[0072] Synthetic fibers may have a fiber diameter of 6.0 μm or more and 20.0 μm or less. The fiber diameter of synthetic fibers may be 6.5 μm or more, 7.5 μm or more, 9.0 μm or more, or 10.0 μm or more. The fiber diameter of synthetic fibers may be 19.0 μm or less, 16.0 μm or less, or 15.0 μm or less. The method for determining the fiber diameter of synthetic fibers is as explained earlier in relation to cellulosic fibers.

[0073] Examples of natural fibers that are not cellulose-based include silk, wool, and animal hair. Examples of inorganic fibers include glass fibers, metal fibers, and carbon fibers.

[0074] In this embodiment, pulp may be used as the short fibers. Pulp is hydrophilic and tends to intertwine well with the fibers of fiber layer B located on both sides of fiber layer A when a laminated nonwoven fabric is manufactured by the water flow entanglement method described later. Fiber layer A containing pulp can also be provided in the form of a wet nonwoven fabric, commonly referred to as tissue paper, before being intertwined with fiber layer B, as described later, thus facilitating the manufacture of the nonwoven fabric. Furthermore, because pulp is hydrophilic, it is easy to impregnate the nonwoven fabric with liquid and to retain liquid. Moreover, because pulp tends to exist in a fibrilized state, it is easy to intertwine the fibers when intertwining them using the method described later. Pulp also has a flattened shape and, when dry, forms hydrogen bonds between the flattened surfaces, exhibiting relatively high strength and improving runability during product processing, while when wet, the hydrogen bonds are broken, making the nonwoven fabric flexible.

[0075] As pulp, for example, pulp manufactured by conventional methods using coniferous or hardwood wood may be used, specifically, for example, mechanical pulp, chemical pulp, or recycled pulp. Alternatively, as pulp, non-wood pulp made from plant fibers including straw, bamboo, bagasse, esparto, other reeds and grasses, cotton linters, Manila hemp, flax, hemp, ramie, kenaf, rug, and other textile waste may be used. When pulp is used as short fibers, the fineness of the pulp may be, for example, about 1.0 to 4.0 dtex, particularly about 1.3 to 3.5 dtex, and the fiber length may be, for example, 0.8 mm to 4.0 mm, particularly 1.0 mm to 3.0 mm, more particularly 1.2 mm to 2.0 mm, but pulp with fineness and / or fiber length outside this range may also be used. When short fibers are used in pulp, the fiber length and fiber width of the pulp are measured as length-weighted average fiber length and length-weighted average fiber width according to JIS P 8226-2:2011 Pulp - Optical automated analysis method. The length-weighted average fiber length and length-weighted average fiber width can be measured using a fiber length distribution analyzer (for example, Valmet Co., Ltd., instrument name "FS-5").

[0076] [Staple fiber] The fiber web B of this embodiment contains staple fibers with a fiber length of 20 mm to 100 mm. The fiber length of the staples is measured according to JIS L 1015:2010 (Method D) if they are synthetic fibers, and if they are natural fibers such as cotton, they are measured as the length-weighted average fiber length using a fiber length measurement system manufactured by REMIER (https: / / www.berthold-jp.com / fibershape / ).

[0077] The fiber length of the staple fibers may be, for example, 20 mm or more and 100 mm or less, particularly 22 mm or more and 70 mm or less, and more particularly 30 mm or more and 64 mm or less.

[0078] Staple fibers may be synthetic fibers, cellulosic fibers, natural fibers other than cellulosic fibers, or inorganic fibers. Examples of these fibers are as previously described in relation to short fibers.

[0079] In this embodiment, cellulose fibers may be used as staple fibers. Cellulose fibers are generally hydrophilic, and therefore tend to entangle well with fiber layer A when manufacturing laminated nonwoven fabric by the water flow entanglement method described later. Hydrophilic cellulose fibers also make it easy to impregnate the nonwoven fabric with liquid and to retain liquid. Furthermore, since most cellulose fibers are natural fibers or fibers made from natural materials, they have a good feel. In addition, cellulose fibers have the advantage of being easily accepted by consumers who are highly conscious of environmental issues and / or who have a preference for natural materials.

[0080] As cellulose fibers, for example, regenerated fibers, particularly rayon, and cotton can be used. Regenerated fibers are preferred because their fineness can be easily adjusted and they have little variation. Among regenerated fibers, rayon can make nonwoven fabrics soft. Cotton is a natural fiber and has a proven track record of being widely used in products that come into contact with the skin, such as underwear, so it is preferred in applications where it comes into contact with the skin.

[0081] When using cellulose fibers as staple fibers, synthetic fibers may also be used as staple fibers. By using synthetic fibers in combination, the strength of the nonwoven fabric is improved, and the strength of the nonwoven fabric can be adjusted according to the application. In addition, by using synthetic fibers in combination, the stiffness and flexibility of the nonwoven fabric when wet can be increased compared to when using only cellulose fibers, and the stiffness and flexibility can be adjusted according to the application.

[0082] Furthermore, synthetic fibers have mechanical or three-dimensional crimp, and since this crimp is firm, it facilitates good entanglement between fibers in the CD direction. Therefore, by using synthetic fibers together with staple fibers, the elongation at break in the CD direction of the nonwoven fabric can be increased, making it easier to obtain a nonwoven fabric that is resistant to tearing.

[0083] As synthetic fibers, for example, polyester monofibers such as polyethylene terephthalate can be used. Compared to other synthetic fibers, polyester fibers tend to make nonwoven fabrics bulkier, and because polyester fibers are flexible and strong, using them in combination with cellulose fibers makes it easier to obtain a nonwoven fabric that is strong, flexible, and tear-resistant. As synthetic fibers, polyolefin monofibers such as polypropylene can also be used. Since polyolefin monofibers themselves are water-repellent, they can reduce entanglement when water entanglement is induced. This prevents excessive entanglement and makes the nonwoven fabric flexible. As staple fibers, split-type composite fibers whose fiber cross-section consists of multiple sections can also be used. When nonwoven fabric is manufactured using a manufacturing method involving water jetting described later, some or all of the sections of split-type composite fibers split to form fibers with smaller fineness, making the nonwoven fabric denser and giving it a smoother feel. Split-type composite fibers may consist of combinations such as polyethylene terephthalate / polyethylene, polypropylene / polyethylene, or polyethylene terephthalate / polypropylene. Among these, the combination of polyester and polyethylene exhibits good splitting properties when entangled in water flow, making it easier to achieve a good texture in nonwoven fabrics.

[0084] [Fiber Web A] Fiber web A contains short fibers with a fiber length of less than 20 mm. Fiber web A contains, for example, 50% or more by mass of short fibers, particularly 60% or more by mass, and more particularly 70% or more by mass. Fiber web A may consist only of short fibers. When fiber web A consists only of short fibers, the confluence with fiber web B is better.

[0085] Before integration with fiber web B, fiber web A may be in the form of a wet-rolled paper web, a wet-rolled nonwoven fabric, an airlaid web, or an airlaid nonwoven fabric. In these webs or nonwoven fabrics, the fiber orientation is relatively random, which makes it easier to achieve a good weave in the nonwoven fabric after lamination. However, the form of fiber web A before integration with fiber web B is not limited to these; for example, it may be a card web or another form of nonwoven fabric. Fiber web A may be a wet-rolled nonwoven fabric.

[0086] Fiber web A may be a wet-laid nonwoven fabric containing pulp. Fiber web A may be a wet-laid nonwoven fabric consisting solely of pulp. A wet-laid nonwoven fabric in which fiber web A consists solely of pulp is also called tissue. Fiber web A may be a wet-laid nonwoven fabric consisting of pulp, and may be crepe paper.

[0087] The fiber web A may be crepe paper with a crepe ratio of 10.0% or more and 30.0% or less, as measured by the underwater elongation method. This makes it easier to apply tension uniformly in the width direction of the fiber web A during the manufacturing process, improving the texture of the laminated nonwoven fabric. The crepe ratio may be 13.0% or more. The crepe ratio may be 28.0% or less, 25.0% or less, or 23.0% or less. The crepe ratio may be 10.0 to 28.0%, 13.0 to 25.0%, or 14.0 to 23.0%.

[0088] The crepe ratio can be measured by the following method. This measurement method is disclosed in Japanese Patent Publication No. 2017-160552 and is known to those skilled in the art.

[0089] (1) Fill a container larger than the dimensions of the sample with enough water to completely immerse the sample. (2) Cut out a sample from fiber web A that is 30 mm or larger (preferably 100 mm) in the MD direction and 25 mm in the CD direction. (3) Immerse the sample in the water in the container described above. (4) After 60 seconds, measure the length of the sample in the MD direction and calculate the crepe ratio using the following formula.

[0090] Formula: Crepe ratio (%) = 100 × (L2 - L1) / L1 L1: MD direction length of the sample before immersion L2: MD direction length of the sample after immersion

[0091] [Textile Web B] Fiber web B contains staple fibers with a fiber length of 20 mm to 100 mm. Fiber web B contains staple fibers in an amount of, for example, 50% by mass or more, particularly 70% by mass or more, and more particularly 80% by mass or more. Fiber web B may consist only of staple fibers. When fiber web B consists only of staple fibers and does not contain fibers with a fiber length of less than 20 mm and / or fibers with a fiber length exceeding 100 mm, it is easier to obtain a nonwoven fabric having the elongation characteristics described below. Also, when fiber web B consists only of staple fibers and does not contain short fibers, fiber ends are less likely to protrude from the surface of the nonwoven fabric, making it easier to obtain a nonwoven fabric with a good tactile feel.

[0092] The fiber web B may be in any form, such as a card web, air-lay web, or wet-machine paper web, including parallel webs, cross webs, semi-random webs, and random webs. Parallel webs and semi-random webs are preferred because they result in a smoother surface for the nonwoven fabric.

[0093] As mentioned above, the fiber web B may contain cellulosic fibers. The cellulosic fibers may make up, for example, 40% or more by mass, particularly 60% or more by mass, and more particularly 70% or more by mass, when the staple fibers contained in the fiber web B are taken as 100% by mass. The fiber web B may consist only of cellulosic fibers.

[0094] Alternatively, fiber web B may contain 40% to 100% by mass of cellulose fibers, particularly 70% to 100% by mass, when the staple fibers contained in fiber web B are considered as 100% by mass, with the other staple fibers being synthetic fibers. The significance of using cellulose fibers and synthetic fibers in combination is explained above in the section on staple fibers. Examples of cellulose fiber / synthetic fiber combinations include rayon / polyethylene terephthalate fiber, rayon / polypropylene fiber, rayon / split composite fiber (e.g., polyethylene terephthalate / polyethylene), lyocell / polyethylene terephthalate fiber, lyocell / polypropylene fiber, lyocell / split composite fiber, cotton / polyethylene terephthalate fiber, and cotton / split composite fiber.

[0095] Fiber web A is the web that will become fiber layer A, as described later, and fiber web B is the web that will become fiber layer B, as described later.

[0096] Fiber web A may contain 50% by mass or more of short fibers, and fiber web B may contain 50% by mass or more of staple fibers. This can lead to better intertwining of fiber web A and fiber web B, potentially increasing the integrity of the laminated nonwoven fabric. As a result, delamination and fuzzing are suppressed, and the handling and processability of the laminated nonwoven fabric can be further improved.

[0097] The fiber webs B located on both surfaces of fiber web A may be the same or different. The two fiber webs B may differ from each other, for example, in the type and / or proportion of cellulosic fibers, and / or in their basis weight.

[0098] The basis weights of fiber web A and fiber web B are appropriately selected according to the desired basis weight of the laminated nonwoven fabric. For example, the basis weight of fiber web A may be selected so as not to exceed 60% by mass of the total basis weight of the laminated nonwoven fabric, particularly so as not to exceed 50% by mass, more particularly so as to be 10-45% by mass, and even more particularly so as to be 10-35% by mass. If the proportion of fiber web A exceeds 60% by mass (i.e., if the proportion of fiber web B combined is 40% by mass or less), the entire sheet becomes paper-like, the texture becomes hard, and the adhesion to the skin deteriorates when the laminated nonwoven fabric is used as a liquid-impregnated skin covering sheet. On the other hand, if the proportion of fiber web A is small (i.e., if the proportion of fiber web B is large), the weave of the laminated nonwoven fabric may be poor.

[0099] The basis weight of fiber web A is, for example, 10.0 g / m². 2 More than 40.0g / m 2 The following is acceptable: The basis weight of fiber web A is 11.0 g / m². 2 The above is acceptable, and 12.0 g / m² 2 The above is sufficient, and 12.5 g / m 2 The above is acceptable, and 13.0 g / m² 2 The above is acceptable. The basis weight of fiber web A is 37.0 g / m². 2 The following may be used: 35.0 g / m 2 The following may be used: 30.0 g / m 2 The following may be used: 28.0 g / m² 2 The following may apply: The basis weight of fiber web A is 11.0 to 37.0 g / m². 2 It is acceptable for it to be 12.0 to 35.0 g / m². 2 It is acceptable for it to be 12.5-30.0 g / m². 2 It is acceptable for it to be between 13.0 and 28.0 g / m². 2 That's fine.

[0100] The basis weight per layer of fiber web B is, for example, 10.0 g / m². 2 More than 50.0g / m 2 The following is acceptable: The basis weight per layer of fiber web B is 12.0 g / m². 2 The above is acceptable, and 13.0 g / m²2 The above is acceptable, and 14.0 g / m² 2 The above is acceptable, and 15.0 g / m² 2 The above is acceptable. The basis weight per layer of fiber web B is 48.0 g / m². 2 The following may be used: 47.0 g / m² 2 The following may be used: 46.0 g / m² 2 The following may be used: 45.0 g / m 2 The following is acceptable: The basis weight per layer of fiber web B is 12.0 g / m². 2 ~48.0g / m 2 It is acceptable for it to be 13.0 g / m² 2 ~47.0g / m 2 It is acceptable for it to be 14.0 g / m² 2 ~46.0g / m 2 It is acceptable for it to be 15.0 g / m² 2 ~45.0g / m 2 That's fine.

[0101] The basis weight of fiber web A is 10.0 g / m². 2 More than 40.0g / m 2 The following applies, and the basis weight per layer of fiber web B is 10.0 g / m². 2 More than 50.0g / m 2 The following is acceptable:

[0102] The basis weight of the laminated web is, for example, 40-140 g / m². 2 And especially 50-120 g / m 2 And more specifically, 60-100 g / m 2 The basis weight of the laminated web is 40 g / m². 2 With these specifications, a sufficient amount of liquid can be easily impregnated, and the material can have a firm feel when held in the hand. The basis weight of the laminated web is 140 g / m². 2 The following would improve ease of handling.

[0103] (1) Fabrication of laminated webs A laminated web is created by laminating fiber web B onto both surfaces of fiber web A.

[0104] (2) Water flow entanglement treatment A water stream is sprayed onto one or both sides of the laminated web (water entanglement treatment). This causes the fibers constituting fiber web A and fiber web B to entangle with each other, resulting in a laminated nonwoven fabric in which fiber web A and fiber web B are integrated. This laminated nonwoven fabric has good form.

[0105] In the water flow entanglement treatment, for example, a water flow (typically a columnar water flow) is sprayed onto a laminated web placed on a support. The water flow entanglement treatment may be carried out by spraying a water flow at a water pressure of 1 MPa to 10 MPa onto the front and back surfaces of the laminated web 1 to 5 times each, from a nozzle having orifices with a hole diameter of 0.05 mm to 0.5 mm spaced at intervals of 0.2 mm to 1.5 mm. The water pressure is preferably 1 MPa to 15 MPa, and more preferably 1 MPa to 10 MPa.

[0106] In the manufacturing method of this embodiment, at least one of the water jet injections is performed as a suction water jet injection, in which the water jet injected onto the laminated web is sucked up. The suction water jet injection is performed by placing the laminated web on a support made of a support having a warp diameter of 0.05 mm to 0.2 mm, a weft diameter of 0.05 mm to 0.2 mm, and a mesh count of 70 to 110 mesh (for example, a plain weave support with 80 to 100 mesh made by weaving monofilaments in a plain weave structure), or perforated metal.

[0107] A support made of perforated metal is a support in which openings are formed in a metal plate, and the area between the openings that does not allow water flow to pass through (non-opening region) is wider compared to, for example, a mesh-like support made of monofilaments woven in a plain weave structure. In this non-opening region and near the openings, it is thought that the attraction of the water flow, combined with other factors, makes the orientation of the fibers relatively random locally and strengthens the entanglement of the fibers in some areas. On the other hand, compared to a mesh-like support made of monofilaments woven in a plain weave structure, a support made of perforated metal tends to have a lower overall degree of fiber entanglement because the water that hits the non-opening region "scatters" the fibers.

[0108] The suction water jet injection may be performed once or more times with one side of the laminated web in contact with the support made of perforated metal, and once or more times with the other side of the laminated web in contact with the support made of perforated metal.

[0109] The support made of perforated metal has an area of ​​0.05 mm² per unit. 2 3.0mm or more 2 The openings described below may be arranged regularly such that the opening ratio on the support surface is between 7% and 26%. With such a support, it is easy to obtain a nonwoven fabric having the stretchability characteristics of this embodiment. The area of ​​each opening is particularly 0.05 mm². 2 3.0mm or more 2 The following is more specifically 0.07mm 2 1.50mm 2 The following may apply, and the opening ratio may be particularly 7% to 26%, and more particularly 9% to 25%. The shape of the opening may be circular, elliptical, triangular, square, rectangular, etc., and may be particularly circular.

[0110] For example, a support made of perforated metal may have openings of the same shape and dimensions arranged in a staggered pattern at 45° or 60° angles. The angles of the staggered arrangement correspond to the base angles of the isosceles triangles formed by connecting the openings. Such a support can perform suction water jet spraying more uniformly, making the entire nonwoven fabric surface more uniform. Such a support may have, for example, circular openings with a diameter of 0.13 mm to 1.96 mm arranged in a staggered pattern with a diagonal pitch (distance between the centers of the openings) of 0.90 mm to 1.50 mm and a lateral pitch of 0.9 mm to 1.5 mm. Alternatively, a support made of perforated metal may have openings of the same shape and dimensions arranged in a grid pattern (i.e., the openings are located at the intersections of the grid).

[0111] The water flow suction is performed by applying negative pressure to the side opposite to the side on which the nonwoven fabric support is placed. The negative pressure may be applied so that the pressure (atmospheric pressure) on the side opposite to the side on which the nonwoven fabric support is placed is, for example, between 2 kPa and 20 kPa. By applying negative pressure to suction the water flow, it is thought that the water flow that hits the non-openings of the support will flow toward the openings, thereby partially strengthening the entanglement of the fibers.

[0112] The support used when performing suction water jet injection may be cylindrical in shape. In this case, the water jet is suctioned from inside the cylinder. By using a cylindrical support and performing suction water jet injection from inside the cylinder, the apparatus can be simplified, and the fiber web can be made to adhere closely to the support, allowing for efficient entanglement of the fibers.

[0113] In the manufacturing method of this embodiment, before performing suction water jet spraying, a film-like flow of water may be applied to the laminated web placed on the support. Applying a film-like flow of water can improve the adhesion of the laminated web to the support during suction water jet spraying, and allow for more efficient suction water jet spraying. The film-like flow of water may be applied to the laminated web using a flow coater. Alternatively, the film-like flow of water may be drawn in by negative pressure, which further improves the adhesion of the laminated web to the support. The negative pressure may be, for example, 2 kPa or more and 20 kPa or less.

[0114] The water entanglement treatment may include, in addition to suction water jetting, water jetting without suction (hereinafter referred to as "non-suction water jetting" for convenience). Non-suction water jetting may be performed to strengthen the entanglement between fibers and / or to improve the texture of the nonwoven fabric. Non-suction water jetting may be performed by placing the nonwoven fabric on a support made of perforated metal or a plain-woven mesh support.

[0115] In the manufacturing method of this embodiment, non-suction water jet spraying may be performed on one side of the laminated web, and suction water jet spraying may be performed on the other side. Alternatively, both non-suction water jet spraying and suction water jet spraying may be performed on one side of the laminated web. In either case, non-suction water jet spraying may be performed either before or after suction water jet spraying. Alternatively, in the manufacturing method of this embodiment, only suction water jet injection may be performed.

[0116] In both suction water jet injection and non-perforated metal water jet injection, the water jet may be ejected from a nozzle having orifices with a hole diameter of 0.05 mm or more and a diameter of 0.5 mm or less, spaced at intervals of 0.2 mm or more and 1.5 mm or less. The distance between the nozzle and the web may be, for example, 5 mm to 100 mm, and particularly 10 mm to 50 mm.

[0117] (3) Draft After fabricating the fiber webs (1), tension may be applied to fiber webs A and B until the water entanglement treatment (2) is completed. By spraying water onto the tensioned or released fiber webs, the orientation of the fibers becomes random, and the laminated nonwoven fabric may experience high stress in the MD direction at low elongation and low stress in the CD direction at low elongation. This can further improve handling and processability.

[0118] In the following, the process of applying tension to a fiber web is referred to as drafting the fiber web. For example, a fiber web can be drafted by making the speed of the support that transports the fiber web during water jetting (transport speed) greater than the speed of the fiber web immediately after it is fed out from the winding roll (feeding speed).

[0119] The drafting of the fiber web may be carried out throughout the entire process from the fabrication of the fiber web (1) to the completion of the water entanglement treatment (2), or it may be carried out only in some of the processes. In particular, it may be carried out after the fabrication of the fiber web (1) until it is subjected to water jetting. The draft ratio can be adjusted, for example, by pulling the web with a drafter.

[0120] The draft ratio of fiber web B is the ratio (conveying speed / feeding speed) of the conveyor being subjected to water entanglement treatment to the speed at which fiber web B is discharged (feeding speed). The draft ratio of fiber web A is the ratio (conveying speed / discharge speed) of the conveyor speed when fiber web A is discharged and placed on the conveyor to the conveyor speed (discharge speed) of the conveyor being subjected to water entanglement treatment.

[0121] The draft ratios of both fiber webs A and B may be greater than 1.0. When the draft ratios of both are greater than 1.0, the fiber webs are under tension.

[0122] The above draft ratio of fiber web B may be 1.03 or more and 1.60 or less. If the above draft ratio of fiber web B is 1.03 or more, the stress at low elongation in the MD direction becomes large, which can suppress the narrowing of the width of fiber web B due to tension during the manufacturing process. If the above draft ratio of fiber web B is 1.60 or less, the texture of the laminated nonwoven fabric improves, and the low elongation stress in the MD direction becomes within an appropriate range, which can further improve adhesion to the skin. The above draft ratio of fiber web B may be 1.05 or more and 1.50 or less, 1.05 or more and 1.27 or less, or 1.07 or more and 1.24 or less.

[0123] If the fibers constituting the fiber web B are chemical or synthetic fibers with relatively long fiber lengths (35 mm or more), the draft ratio may be 1.05 or more and 1.25 or more, and 1.07 or more and 1.16 or less. If the fibers constituting the fiber web B have relatively short fiber lengths or inconsistent fiber lengths (for example, natural fibers), the draft ratio may be 1.07 or more and 1.25 or more, and 1.10 or more and 1.24 or less.

[0124] The above draft ratio of fiber web A may be 1.005 or more and 1.15 or less. If the above draft ratio of fiber web A is 1.005 or more, wrinkles will be less likely to form in fiber web A, which may improve the texture of the laminated nonwoven fabric. If the above draft ratio of fiber web A is 1.15 or less, fiber web A will be less likely to break, which may improve the texture of the laminated nonwoven fabric. The above draft ratio of fiber web A may be 1.01 or more and 1.14 or less, and may be 1.03 or more and 1.13 or less.

[0125] [Laminated nonwoven fabric] Laminated nonwoven fabric is a laminated nonwoven fabric in which fiber layer B is located on both surfaces of fiber layer A, and fiber layer A and fiber layer B are integrated by entanglement. In laminated nonwoven fabric, it is preferable that the fibers are not integrated by adhesion. Laminated nonwoven fabric in which the fibers are not adhered to each other has a better feel and is more flexible. The basis weight of the laminated nonwoven fabric is as previously described in relation to laminated webs.

[0126] Fiber layer A is formed from the fiber web A described above, and fiber layer B is formed from the fiber web B described above. The types and proportions of fibers contained in fiber layers A and B are as previously described in relation to fiber webs A and B. The basis weight of fiber layers A and B is also as previously described in relation to fiber webs A and B. The morphology of fiber layers A and B is also as previously described in relation to fiber webs A and B.

[0127] The 20% elongation stress in the MD direction of the laminated nonwoven fabric may, under standard conditions (dry), be, for example, 15 N / 5 cm to 80 N / 5 cm, particularly 20 N / 5 cm to 70 N / 5 cm, and more particularly 22 N / 5 cm to 60 N / 5 cm. The 20% elongation stress in the MD direction of the laminated nonwoven fabric may, under wet conditions, be, for example, 9.5 N / 5 cm to 40 N / 5 cm, particularly 9.8 N / 5 cm to 35 N / 5 cm, and more particularly 10 N / 5 cm to 32 N / 5 cm.

[0128] The stress of the laminated nonwoven fabric at 20% elongation in the CD direction may be, for example, 1 N / 5 cm to 5 N / 5 cm, particularly 1.5 N / 5 cm to 4.7 N / 5 cm, and more particularly 2 N / 5 cm to 4.5 N / 5 cm, under standard conditions (dry). The stress of the laminated nonwoven fabric at 20% elongation in the CD direction may be, for example, 0.5 N / 5 cm to 3.0 N / 5 cm, particularly 0.7 N / 5 cm to 2.5 N / 5 cm, and more particularly 1.0 N / 5 cm to 2.3 N / 5 cm, under wet conditions.

[0129] The 20% elongation stress of a laminated nonwoven fabric is an indicator of the force applied when using a product containing the laminated nonwoven fabric while slightly stretched. If this stress is too low, the product may stretch more than intended by the user, and if it is too high, for example, when the product is used as a liquid-impregnated skin covering sheet, the adhesion to the skin may be insufficient.

[0130] The 20% elongation stress in the MD and CD directions of the laminated nonwoven fabric is greatly influenced by the fracture stress or low elongation stress of the fiber layer A (fiber web A). In this embodiment, since the specific tensile strength obtained by dividing the tensile strength of the fiber web A in the MD or CD direction by the basis weight is within a certain range, the 20% elongation stress in the MD and CD directions of the laminated nonwoven fabric is likely to fall within the above range.

[0131] In addition to the 20% elongation stress in the MD and CD directions of the laminated nonwoven fabric, the fracture stress or low elongation stress of fiber layer A (fiber web A) also significantly affects the elongation stress of the laminated nonwoven fabric between 1% and 20% in the MD and CD directions.

[0132] If the fiber web A satisfies at least one of the above (A1) and (A2), for example, the 1% elongation stress of the laminated nonwoven fabric in the MD direction may be, for example, 0.50 N / 5cm to 7.0 N / 5cm at standard time (dry), and the 1% elongation stress of the laminated nonwoven fabric in the CD direction may be, for example, 0.12 N / 5cm to 0.6 N / 5cm at standard time (dry). Similarly, the 3% elongation stress of the laminated nonwoven fabric in the MD direction may be, for example, 2.0 N / 5cm to 17.0 N / 5cm at standard time (dry), and the 3% elongation stress of the laminated nonwoven fabric in the CD direction may be, for example, 0.25 N / 5cm to 1.5 N / 5cm at standard time (dry).

[0133] The relatively high tensile stress between 1% and 20%, particularly between 1% and 5% (low tensile stress), provides adequate rigidity and prevents twisting when, for example, laminated nonwoven fabric is used as a dry wiper.

[0134] The laminated nonwoven fabric of this embodiment is particularly suitable for applications where it is impregnated with liquid. Examples of applications where it is impregnated with liquid include skin covering sheets, wet wipes, disposable hand towels, and adhesive patches. The laminated nonwoven fabric of this embodiment is suitable, for example, for use in dry wipers.

[0135] When the laminated nonwoven fabric of this embodiment is impregnated with a liquid to provide a liquid-impregnated skin covering sheet for personal use, such as a face mask, exfoliation sheet, and décolleté sheet, the liquid containing an active ingredient (e.g., a cosmetic) may be impregnated in an amount of 500 parts by mass or more and 2000 parts by mass or less per 100 parts by mass of the nonwoven fabric, more particularly 600 parts by mass or more and 1800 parts by mass or less, and more particularly 700 parts by mass or more and 1500 parts by mass or less. The active ingredient is, for example, a moisturizing ingredient, an exfoliating ingredient, an antiperspirant ingredient, a fragrance ingredient, a whitening ingredient, a blood circulation promoting ingredient, an ultraviolet protection ingredient, and a slimming ingredient, but is not limited to these.

[0136] The face mask is provided in a form suitable for covering the face, and further, with punched-out openings or cutouts as needed in areas corresponding to the eyes, nose, and mouth. Alternatively, the face mask may be shaped to cover only a portion of the face (e.g., around the eyes, mouth, nose, or cheeks). Alternatively, the face mask may be provided as a set consisting of a sheet that covers around the eyes and a sheet that covers around the mouth, or as a set of sheets that cover three or more portions separately.

[0137] A callus care sheet is a skin covering sheet used on areas where calluses are thick and prone to hardening, such as heels, elbows, and knees. By impregnating it with a liquid containing callus-softening and moisturizing components, it exhibits effects that promote moisturizing and softening of calluses, or promote the removal of excess calluses. The nonwoven fabric of this embodiment can be used as a base material in any callus care sheet that exhibits any of these effects or benefits. Callus care sheets, for example, callus care sheets for heels, are provided in a form that has cuts and / or notches, and / or punched-out openings in part of the sheet, so that the sheet can easily conform to the curve of the heel when applied.

[0138] A liquid-impregnated skin covering sheet may be a moisturizing sheet impregnated with a liquid containing moisturizing ingredients or other beneficial substances, used for moisturizing or other care of any part of the body (for example, the neck, the back of the hands, or the area from the neck to the chest (also known as the décolleté)). Alternatively, a liquid-impregnated skin covering sheet may be a slimming sheet impregnated with a liquid containing slimming ingredients. A slimming sheet may be used, for example, by being applied to the thighs or abdomen.

[0139] When using the nonwoven fabric of this embodiment as a wet wipe, a disposable hand towel, etc., it may be impregnated with water or an aqueous solution containing a cleaning component in an impregnation amount of 100 parts by mass or more and 1000 parts by mass or less per 100 parts by mass of the nonwoven fabric. The impregnation amount may be 150 parts by mass or more, 700 parts by mass or less, or 500 parts by mass or less per 100 parts by mass of the nonwoven fabric.

[0140] Wet wipes may be for use on people or on objects. When used on people, they can be used as wet tissues or baby wipes. When used on objects, they may be used for wiping floors, kitchens, toilets, bathtubs, furniture, vehicles, walls, screens, and windows. Wipers for objects may be used by attaching them to a jig in which a wiper attachment part is provided at the end of a rod-shaped object.

[0141] Second Embodiment In the method for manufacturing the laminated nonwoven fabric of this embodiment, the fiber web A satisfies at least one selected from (B1) to (B3) below. Details of the fiber webs A and B used in the second embodiment are as described in the first embodiment. Details of the laminated nonwoven fabric obtained in the second embodiment are as described in the first embodiment.

[0142] The conditions (B1) to (B3) of the second embodiment will be described below. Fiber web A is, The specific tensile strength (N·m / g) (hereinafter also called specific modulus) is obtained by dividing the stress (N / m) in the CD direction when the paper is stretched 2% or 3% from the zero point at standard time by the basis weight, as determined in accordance with JIS P 8113:2006 Paper and cardboard - Test methods for tensile properties - Part 2: Constant-rate stretching method, and is then given the ID. 2-CD ID 3-CD The specific modulus (N·m / g) obtained by dividing the stress (N / m) in the CD direction when the material is stretched 3% from the zero point in a wet state, as determined in accordance with JIS P 8135:1998 Paper and cardboard - Wet tensile strength test method, by the basis weight is IW 3-CD When this is done, at least one of the following (B1) to (B3) must be satisfied. (B1) 0.5 N·m / g ≤ ID 2-CD ≤3.5 N·m / g (B2) 1.0 N·m / g ≤ ID 3-CD ≤4.5 N·m / g (B3) 0.34 N·m / g ≤ IW 3-CD ≤0.75 N·m / g

[0143] In the initial stages of elongation of a laminated nonwoven fabric (at low elongation), the fibers are relatively flexible and can move freely. Therefore, the tensile properties are not significantly affected by the degree of entanglement between fibers (between upper and lower layers and the middle layer, or between fibers within each layer), and the properties of the middle layer containing short fibers are dominant. In this embodiment, the specific modulus in the CD direction at standard time when the fiber web A is elongated to 2% or 3%, which is the initial stage of elongation, is within a certain range. This allows for a balance of a certain degree of rigidity and flexibility even in a wet state, improving handling.

[0144] Fiber web A may satisfy all of the above conditions (B1) to (B3).

[0145] (B1) Modulus ID at 2% extension in the CD direction relative to standard time 2-CD It may satisfy any of the following conditions (B1a) to (B1c). The unit (N·m / g) is omitted. (B1a) 0.6 ≤ ID 2-CD ≤3.6 (B1b) 0.7 ≤ ID 2-CD ≤3.3 (B1c)0.8≦ID 2-CD ≤3.0

[0146] (B2) Modulus ID at 3% extension in the CD direction relative to standard time 3-CD It may satisfy any of the following conditions (B2a) to (B2c). The unit (N·m / g) is omitted. (B2a) 1.1 ≤ ID 3-CD ≤4.3 (B2b) 1.2 ≤ ID 3-CD ≤4.0 (B2c)1.3≦ID 3-CD ≤3.5

[0147] (B3) Specific modulus IW at 3% elongation in the CD direction when wet 3-CD It may satisfy any of the following conditions (B3a) to (B3c). The unit (N·m / g) is omitted. (B3a) 0.34 ≤ IW 3-CD ≤0.74 (B3b) 0.35 ≤ IW3-CD ≤0.73 (B3c)0.36≦IW 3-CD ≤0.70

[0148] Fiber web A may satisfy all of the above (B1a), (B2a), and (B3a). Fiber web A may satisfy all of the above (B1b), (B2b), and (B3b). Fiber web A may satisfy all of the above (B1c), (B2c), and (B3c).

[0149] Fiber web A may satisfy at least one selected from (B1) to (B3) above, along with at least one selected from (A1) to (A4) above. [Examples]

[0150] This embodiment will be described below with reference to examples. [Fiber Web A] Tables 1 and 2 show the composition and mechanical properties of the fiber web A used.

[0151] [Table 1]

[0152] [Table 2]

[0153] [Textile Web B] Table 2 shows the composition of the fiber web B used. The details of the staple fibers constituting fiber web B are as follows: 1.7 Rayon: Rayon with a fineness of 1.7 dtex and a fiber length of 40 mm (manufactured by Lenzing, product name SPV) Cotton: Length-weighted average fiber length of 23mm (manufactured by Marusan Sangyo Co., Ltd., product name: MSD Cotton) 1.45PET: A single fiber made of polyethylene terephthalate with a fineness of 1.45 dtex and a fiber length of 38 mm (manufactured by Toray Industries, Inc., product name T403D). PET / PE split fiber: Fineness 2.2 dtex, fiber length 51 mm (manufactured by Yamato Spinning Co., Ltd., product name: DFS(SH))

[0154] [Example 1] Using only 1.7 rayon, the basis weight is 21.5 g / m². 2 Fiber web B was fabricated using a semi-random carding machine. This fiber web B was placed on both surfaces of the wet nonwoven fabric A-1, which is fiber web A, to create a laminated web.

[0155] The resulting laminated web was subjected to a water flow entanglement treatment. As a support, a cylindrical perforated metal with a 10% opening ratio was used, with circular openings of 0.35 mm in diameter arranged at a 60° staggered pattern with a pitch of 1.05 mm. The support was rotated so that the conveying speed of the laminated web was 51.8 m / min.

[0156] While the laminated web was being transported on the support, a columnar water stream at a pressure of 4.0 MPa was injected once from a nozzle with orifices of 0.10 mm in diameter spaced 0.6 mm apart on one side, and a columnar water stream at a pressure of 3.5 MPa was injected once from a nozzle with orifices of 0.12 mm in diameter spaced 1.2 mm apart. Next, a columnar water stream at a pressure of 3.5 MPa was injected once from a nozzle with orifices of 0.13 mm in diameter spaced 1.0 mm apart on the other side, and a columnar water stream at a pressure of 4.0 MPa was injected once from a nozzle with orifices of 0.10 mm in diameter spaced 0.6 mm apart. The water stream injection was carried out while applying a negative pressure of 11 kPa when injecting water to one side, and while applying a negative pressure of 5.0 kPa when injecting water to the other side.

[0157] As a result, a laminated nonwoven fabric was obtained in which fiber layer B was laminated on both surfaces of fiber layer A. The draft ratio of fiber web A was 1.015. The draft ratio of fiber web B was 1.12.

[0158] [Example 2] 1.7 rayon is blended at 80% by mass, and 1.45 PET at 20% by mass, with a target weight of 26.5 g / m². 2Fiber web B was fabricated using a semi-random carding machine. This fiber web B was placed on both surfaces of the wet nonwoven fabric A-1, which is fiber web A, to create a laminated web.

[0159] While the obtained laminated web was transported on the same support used in Example 1, a columnar water stream at a water pressure of 3.5 MPa was injected once from a nozzle with orifices of 0.12 mm in diameter spaced 1.0 mm apart, and a columnar water stream at a water pressure of 5.0 MPa was injected once from a nozzle with orifices of 0.12 mm in diameter spaced 0.6 mm apart. Subsequently, a columnar water stream at a water pressure of 4.5 MPa was injected once from a nozzle with orifices of 0.13 mm in diameter spaced 1.0 mm apart, and a columnar water stream at a water pressure of 5.0 MPa was injected once from a nozzle with orifices of 0.10 mm in diameter spaced 0.6 mm apart. The water stream injection was carried out from inside the cylindrical support while suction was applied with a negative pressure of 11 kPa when injecting water from one side to the other side, and while suction was applied with a negative pressure of 5.0 kPa when injecting water from the other side to the other side.

[0160] The support was rotated so that the conveying speed of the laminated web was 58 m / min. The draft ratio of fiber web A during the first injection of columnar water was 1.016. The draft ratio of fiber web B during the first injection of columnar water was 1.12.

[0161] As a result, a laminated nonwoven fabric was obtained in which fiber layer B was laminated on both surfaces of fiber layer A.

[0162] [Example 3] Using only PET / PE split fibers, target density 26.5 g / m 2 Fiber web B was fabricated using a semi-random carding machine. This fiber web B was placed on both surfaces of the wet nonwoven fabric A-1, which is fiber web A, to create a laminated web.

[0163] While conveying the obtained laminated web on the same support as that used in Example 1, one surface was once jetted with a columnar water flow at a water pressure of 3.0 MPa from a nozzle provided with orifices having a pore diameter of 0.12 mm at intervals of 1.0 mm, and once jetted with a columnar water flow at a water pressure of 6.0 MPa from a nozzle provided with orifices having a pore diameter of 0.12 mm at intervals of 1.0 mm, and further once jetted with a columnar water flow at a water pressure of 7.0 MPa from a nozzle provided with orifices having a pore diameter of 0.10 mm at intervals of 0.6 mm. The water flow jetting was carried out while sucking the water flow at a negative pressure of 9 kPa from the inside of the cylindrical support. After the suction water flow jetting, the laminate was placed on a 90-mesh plain weave support, and the other surface was once jetted with a columnar water flow at a water pressure of 6.5 MPa from a nozzle provided with orifices having a pore diameter of 0.13 mm at intervals of 1.0 mm, and once jetted with a columnar water flow at a water pressure of 5.5 MPa from a nozzle provided with orifices having a pore diameter of 0.13 mm at intervals of 0.63 mm.

[0164] The support was rotated such that the conveyance speed of the laminated web was 43.1 m / min. The draft ratio of fiber web A during the first columnar water flow jetting was 1.005. The draft ratio of fiber web B during the first columnar water flow jetting was 1.46.

[0165] As described above, a laminated nonwoven fabric in which fiber layer B was laminated on both surfaces of fiber layer A was obtained.

[0166] [Example 4] 80% by mass of 1.7 rayon and 20% by mass of 1.45 PET were blended, and a target basis weight of 31.8 g / m 2 of fiber web B was produced using a semi-random carding machine. This fiber web B was disposed on both surfaces of wet-laid nonwoven fabric A-2 which was fiber web A, to produce a laminated web.

[0167] While conveying the obtained laminated web on the same support as that used in Example 1, one surface was once jetted with a columnar water flow at a water pressure of 2.0 MPa from a nozzle provided with orifices having a pore diameter of 0.12 mm at intervals of 1.0 mm, and once jetted with a columnar water flow at a water pressure of 4.0 MPa from a nozzle provided with orifices having a pore diameter of 0.12 mm at intervals of 1.0 mm, and further once jetted with a columnar water flow at a water pressure of 6.0 MPa from a nozzle provided with orifices having a pore diameter of 0.12 mm at intervals of 1.0 mm. The water flow jetting was performed while suctioning the water flow at a negative pressure of 13 kPa from the inside of the cylindrical support.

[0168] After the suction water flow jetting, the laminate was placed on a 90-mesh plain weave support, and the other surface was once jetted with a columnar water flow at a water pressure of 5.5 MPa from a nozzle provided with orifices having a pore diameter of 0.13 mm at intervals of 1.0 mm, and once jetted with a columnar water flow at a water pressure of 5.0 MPa from a nozzle provided with orifices having a pore diameter of 0.12 mm at intervals of 0.63 mm.

[0169] Through the above steps, a laminated nonwoven fabric in which the fiber layer B was laminated on both surfaces of the fiber layer A was obtained. The draft ratio of the fiber web A during the first columnar water flow jetting was 1.044. The draft ratio of the fiber web B during the first columnar water flow jetting was 1.12.

[0170] [Example 5] Using only cotton, a fiber web B with a target basis weight of 15.8 g / m 2 was produced using a semi-random carding machine. This fiber web B was disposed on both surfaces of the wet-laid nonwoven fabric A-2, which was the fiber web A, to produce a laminated web.

[0171] While the resulting laminated web was being transported on the same support used in Example 1, a columnar water stream at a pressure of 4.0 MPa was injected once from a nozzle with orifices of 0.08 mm in diameter spaced at 0.65 mm intervals on one side, a columnar water stream at a pressure of 4.5 MPa was injected once from a nozzle with orifices of 0.12 mm in diameter spaced at 0.65 mm intervals, and then a columnar water stream at a pressure of 3.5 MPa was injected once from a nozzle with orifices of 0.12 mm in diameter spaced at 1.0 mm intervals. The water streams were injected from inside the cylindrical support while the water stream was being sucked in under a negative pressure of 9 kPa.

[0172] After the suction water jet injection, the laminate was placed on a 90-mesh plain weave support, and a columnar water jet at a water pressure of 4.0 MPa was injected once from a nozzle on the other side, which had orifices with a hole diameter of 0.12 mm spaced at 1.0 mm intervals.

[0173] As a result, a laminated nonwoven fabric was obtained in which fiber layer B was laminated on both surfaces of fiber layer A. The draft ratio of fiber web A during the first injection of columnar water was 1.021. The draft ratio of fiber web B during the first injection of columnar water was 1.21.

[0174] [Example 6] 1.7 rayon is blended at 80% by mass, and 1.45 PET at 20% by mass, with a target weight of 32.5 g / m². 2 Fiber web B was fabricated using a semi-random carding machine. This fiber web B was placed on both surfaces of the wet nonwoven fabric A-3, which is fiber web A, to create a laminated web.

[0175] While the resulting laminated web was being transported on the same support used in Example 1, a columnar water stream at a water pressure of 2.5 MPa was injected once from a nozzle with orifices of 0.12 mm in diameter spaced at 1.0 mm intervals on one side, a columnar water stream at a water pressure of 4.0 MPa was injected once from a nozzle with orifices of 0.12 mm in diameter spaced at 1.0 mm intervals, and then a columnar water stream at a water pressure of 5.5 MPa was injected once from a nozzle with orifices of 0.12 mm in diameter spaced at 1.0 mm intervals. The water streams were injected from inside the cylindrical support while the water stream was being sucked in under a negative pressure of 9 kPa. After the suction water jet injection, the laminate was placed on a 90-mesh plain weave support, and a columnar water jet at a water pressure of 5.0 MPa was injected once from a nozzle with orifices of 0.13 mm in diameter spaced at 1.0 mm intervals on the other side, and a columnar water jet at a water pressure of 5.0 MPa was injected once from a nozzle with orifices of 0.12 mm in diameter spaced at 0.63 mm intervals.

[0176] The support was rotated so that the conveying speed of the laminated web was 32.3 m / min. The draft ratio of fiber web A during the first injection of columnar water was 1.016. The draft ratio of fiber web B during the first injection of columnar water was 1.24.

[0177] As a result, a laminated nonwoven fabric was obtained in which fiber layer B was laminated on both surfaces of fiber layer A.

[0178] [Comparative Example 1] Using only PET / PE split fibers, target density 26.5 g / m 2 Fiber web B was fabricated using a parallel carding machine. This fiber web B was placed on both surfaces of the wet nonwoven fabric X-1, which is fiber web A, to create a laminated web.

[0179] While the resulting laminated web was being transported on a 90-mesh plain weave support, a columnar water stream at a pressure of 3.0 MPa was injected once from a nozzle with orifices of 0.12 mm in diameter spaced at 0.6 mm intervals on one side, and a columnar water stream at a pressure of 6.0 MPa was injected once from a nozzle with orifices of 0.12 mm in diameter spaced at 0.6 mm intervals on the other side, and a columnar water stream at a pressure of 5.0 MPa was injected twice from a nozzle with orifices of 0.12 mm in diameter spaced at 0.6 mm intervals.

[0180] The support was rotated so that the conveying speed of the laminated web was 10 m / min. No drafts were applied to fiber web A and fiber web B.

[0181] As a result, a laminated nonwoven fabric was obtained in which fiber layer B was laminated on both surfaces of fiber layer A.

[0182] [evaluation] The evaluation of the nonwoven fabric was carried out as follows.

[0183] <Tensile strength, elongation> The tensile strength was determined in accordance with JIS L 1913:2010 6.3. A constant-speed tension tensile testing machine was used to conduct tensile tests on dry samples under the conditions of a sample width of 5 cm, a gripping distance of 10 cm, and a tensile speed of 30 ± 2 cm / min. The load value at break (tensile strength), elongation, and the stress required to elongate by a predetermined amount were measured. The tensile tests were performed with the longitudinal (MD direction) and transverse (CD direction) of the nonwoven fabric as the tensile direction. The evaluation results are shown as the average of the values ​​measured for three samples. For measurements under wet conditions, 250 parts by mass of distilled water were used to impregnate 100 parts by mass of the sample. The elongation rate (%) used to determine the stress during extension is as shown in the table below.

[0184] <Rating> The following items (1) to (4) were evaluated, and the total score for each item was calculated. Scoring was done in increments of 0.5 for all evaluations. (1) Processability of nonwoven fabrics during product processing In a state where five 30 cm long (MD direction) × 26 cm wide (CD direction) samples were stacked, the five sheets were simultaneously punched into the face mask face shape using a Thomson blade. The punching state and the punched samples were visually observed by five panelists, and the processability was scored according to the following criteria. 5: When the nonwoven fabric is punched into the face shape, it cuts easily, no fuzz is generated at all, and the processability is favorable. 4: When the nonwoven fabric is punched into the face shape, it cuts easily and a small amount of fuzz is generated, but the processability is favorable. 3: When the nonwoven fabric is punched into the face shape, it cuts easily, and although portions fused to the face shape are observed, the processability is "acceptable". 2: When the nonwoven fabric is punched into the face shape, it cuts easily, but portions fused to the face shape are observed, and a large amount of fuzz is generated, so the processability is "acceptable". 1: When the nonwoven fabric is punched into the face shape, it is difficult to cut, and it fuses to the face shape and cannot be detached, so the processability is "unacceptable".

[0185] (2) Ease of taking the product out of the packaging container 1000 parts by mass of distilled water was impregnated into 100 parts by mass of the nonwoven fabric punched into the face mask face shape. Thereafter, the left and right sides of the face mask were folded in a double gatefold manner, the top and bottom were folded in half, and the face mask was placed into a product bag (pouch). Five monitors scored the ease of taking out the nonwoven fabric when taking it out from the pouch according to the following criteria, and the average value was calculated. 5: When taken out from the packaging container, it does not stretch at all 4: When taken out from the packaging container, it stretches but can be used without problem 3: When taken out from the packaging container, it stretches, and the stretched portion can be noticed when applied to the face, but it is usable 2: When taken out from the packaging container, it adheres tightly to the packaging container, stretches and loses its shape when taken out, but it is usable 1: When taken out from the packaging container, the portions with small area around the eyes and nose tear, making it unusable

[0186] (3) Ease of application to the skin Similar to (2) above, the ease with which face-shaped nonwoven fabrics impregnated with distilled water adhered to the skin was scored according to the following criteria, and the average score was calculated. 5: It has a moderate amount of stretch, and if you can align it with your eyes, it's easy to apply to your face. 4: It has a moderate amount of stretch, and if you can align it with the eyes and mouth, it is easy to apply to the face. 3: The nonwoven fabric can be stretched in both vertical and horizontal directions with minimal force, without distorting the product's shape, allowing it to be used in the product. 2: The stretch is minimal, and the product does not stretch or align properly with the required force to prevent it from collapsing, making it difficult to use. 1: The stretch is insufficient, and when stretched to align the eyes and nose, small areas such as between the eyes tear, rendering the product unusable.

[0187] (4) Resistance to wrinkling A 10cm x 10cm nonwoven fabric was prepared, and 500 parts by mass of distilled water were impregnated into 100 parts by mass of the nonwoven fabric. The resistance to wrinkling when rubbed against the arm was scored according to the following criteria, and the average score was calculated. 5: No creasing at all, even after rubbing more than 10 times. 4: Wrinkling occurs after rubbing 10 times. 3. Wrinkling occurs after rubbing 5 times. Wrinkling occurs after rubbing 2-3 times. 1: Wrinkling occurs at the start of rubbing, making it impossible to rub.

[0188] The evaluation results for each example and comparative example are shown in Tables 3 to 5.

[0189] [Table 3]

[0190] [Table 4]

[0191] [Table 5]

[0192] This embodiment includes the following aspects. (Aspect 1) To create a laminated web by laminating a fiber web B containing staple fibers with a fiber length of 20 mm to 100 mm onto both surfaces of a fiber web A containing short fibers with a fiber length of less than 20 mm, and, This includes spraying a water stream onto one or both surfaces of the laminated web, When the fiber web A has its longitudinal direction as the MD direction and its width direction as the CD direction, JIS P 8113:2006 Paper and cardboard - Test methods for tensile properties - Part 2: Specific tensile strength (ID) in the MD direction determined according to the constant-rate elongation method. MD and the specific tensile strength ID in the CD direction CD A method for manufacturing a laminated nonwoven fabric, wherein at least one of the following (A1) and (A2) is satisfied. (A1) 5.0 N·m / g ≤ ID MD ≤19.0 N·m / g (A2) 1.0 N·m / g ≤ ID CD ≤5.0 N·m / g (Aspect 2) To create a laminated web by laminating a fiber web B containing staple fibers with a fiber length of 20 mm to 100 mm onto both surfaces of a fiber web A containing short fibers with a fiber length of less than 20 mm, and, This includes spraying a water stream onto one or both surfaces of the laminated web, When the fiber web A has its longitudinal direction as the MD direction and its width direction as the CD direction, The aforementioned fiber web A is The specific tensile strength (N·m / g) is obtained by dividing the stress (N / m) in the CD direction when the paper is stretched 2% or 3% from the zero point at standard time by the basis weight, as determined in accordance with JIS P 8113:2006 Paper and cardboard - Test methods for tensile properties - Part 2: Constant-rate stretching method, and is then given the ID. 2-CD ID 3-CDThe specific tensile strength (N·m / g) is calculated by dividing the stress (N / m) in the CD direction when the material is stretched 3% from the zero point in a wet state, as determined in accordance with JIS P 8135:1998 Paper and cardboard - Wet tensile strength test method, by the basis weight. 3-CD A method for manufacturing a laminated nonwoven fabric, wherein at least one of the following (B1) to (B3) is satisfied. (B1) 0.5 N·m / g ≤ ID 2-CD ≤3.8 N·m / g (B2) 1.0 N·m / g ≤ ID 3-CD ≤4.5 N·m / g (B3) 0.33 N·m / g ≤ IW 3-CD ≤0.75 N·m / g (Aspect 3) The aforementioned fiber web A is The wet tensile strength SW in the MD direction, measured in accordance with JIS P 8135:1998 Paper and cardboard - Wet tensile strength test method. MD and the wet tensile strength SW in the CD direction CD Each is weighed (g / m²). 2 Specific wet tensile strength IW divided by ) MD and specific wet tensile strength IW CD A method for manufacturing a laminated nonwoven fabric according to Embodiment 1, wherein at least one of the following (A3) and (A4) is satisfied. (A3) 1.0 N·m / g ≤ IW MD ≤4.1 N·m / g (A4) 0.3 N·m / g ≤ IW CD ≤1.2 N·m / g (Aspect 4) The aforementioned fiber web A is A method for manufacturing a laminated nonwoven fabric according to any of the three embodiments: The air permeability measured in accordance with JIS P 8117:2009 Paper and cardboard - Test methods for air permeability and air permeability resistance (intermediate region) - Gurley method is 0.05 seconds / 300 ml or more and 1.0 seconds / 300 ml or less. (Appendix 5) Furthermore, a method for manufacturing a laminated nonwoven fabric according to any of embodiments 1 to 4, comprising drafting the fiber web B at a draft ratio of 1.03 to 1.60 before the water jet is sprayed. (Aspect 6) Furthermore, the method for manufacturing a laminated nonwoven fabric according to embodiment 5, comprising drafting the fiber web A at a draft ratio of 1.005 or more and 1.15 or less before the water stream is sprayed. (Aspect 7) The basis weight of the aforementioned fiber web A is 10.0 g / m². 2 More than 40.0g / m 2 The following conditions apply, and the basis weight per layer of the fiber web B is 10.0 g / m². 2 More than 50.0g / m 2 A method for manufacturing a laminated nonwoven fabric according to any of the following embodiments 1 to 6. (Pattern 8) A method for producing a laminated nonwoven fabric according to any of embodiments 1 to 7, wherein the fiber web A contains 50% by mass or more of the short fibers and the fiber web B contains 50% by mass or more of the staple fibers. (Aspect 9) A method for producing a laminated nonwoven fabric according to embodiment 8, wherein the fiber web A contains pulp as the short fibers. (Aspect 10) A method for manufacturing a laminated nonwoven fabric according to embodiment 8, wherein the fiber web A is a wet nonwoven fabric. (Aspect 11) The aforementioned fiber web A is A method for producing a laminated nonwoven fabric according to embodiment 10, wherein the crepe ratio measured by the underwater elongation method is 10% or more and 30% or less. (Aspect 12) A method for producing a laminated nonwoven fabric according to embodiment 8, wherein the staple fibers are cellulose fibers. [Industrial applicability]

[0193] The method for manufacturing the laminated nonwoven fabric described herein can provide a user-friendly product when used in liquid-impregnated skin covering sheets or wet wipes.

Claims

1. To create a laminated web by laminating a fiber web B containing staple fibers with a fiber length of 20 mm to 100 mm onto both surfaces of a fiber web A containing short fibers with a fiber length of less than 20 mm, and, This includes spraying a water stream onto one or both surfaces of the laminated web, When the fiber web A has its longitudinal direction as the MD direction and its width direction as the CD direction, JIS P 8113:2006 Paper and cardboard — Test methods for tensile properties — Part 2: Specific tensile strength (ID) in the MD direction determined according to the constant-rate stretching method. ＭＤ and the specific tensile strength ID in the CD direction ＣＤ A method for manufacturing a laminated nonwoven fabric, wherein at least one of the following (A1) and (A2) is satisfied. (A1)5.0N・m / g≦ID ＭＤ ≦19.0N・m / g (A2)1.0N・m / g≦ID ＣＤ ≦5.0N・m / g

2. To create a laminated web by laminating a fiber web B containing staple fibers with a fiber length of 20 mm to 100 mm onto both surfaces of a fiber web A containing short fibers with a fiber length of less than 20 mm, and, This includes spraying a water stream onto one or both surfaces of the laminated web, When the fiber web A has its longitudinal direction as the MD direction and its width direction as the CD direction, The aforementioned fiber web A is The specific tensile strength (N·m / g) is obtained by dividing the stress (N / m) in the CD direction when the paper is stretched 2% or 3% from the zero point at standard time by the basis weight, as determined in accordance with JIS P 8113:2006 Paper and cardboard - Test methods for tensile properties - Part 2: constant-speed stretching method, and is then given as ID. 2-CD ID 3-CD The specific tensile strength (N·m / g) is calculated by dividing the stress (N / m) in the CD direction when the material is stretched 3% from the zero point in a wet state, as determined in accordance with JIS P 8135:1998 Paper and cardboard - Wet tensile strength test method, by the basis weight. 3-CD A method for manufacturing a laminated nonwoven fabric, wherein at least one of the following (B1) to (B3) is satisfied. (B1)0.5N・m / g≦ID 2-CD ≦3.8N・m / g (B2)1.0N・m / g≦ID 3-CD ≦4.5N・m / g (B3)0.33N / iW 3-CD ≦0.75N・m / g

3. The aforementioned fiber web A is JIS P 8135:1998 Paper and cardboard — Wet tensile strength SW in the MD direction as measured in accordance with the wet tensile strength test method. ＭＤ and the wet tensile strength SW in the CD direction ＣＤ Each is the basis weight (g / m ２ Specific wet tensile strength IW divided by ) ＭＤ and specific wet tensile strength IW ＣＤ The method for producing a laminated nonwoven fabric according to claim 1, wherein at least one of the following (A3) and (A4) is satisfied. (A3)1.0N・m / g≦IW ＭＤ ≦4.1N・m / g (A4)0.3N・m / g≦IW ＣＤ ≦1.2N・m / g

4. The aforementioned fiber web A is A method for producing a laminated nonwoven fabric according to claim 1 or 2, wherein the air permeability measured in accordance with JIS P 8117:2009 Paper and cardboard — Test methods for air permeability and air permeability resistance (intermediate region) — Gurley method is 0.05 seconds / 300 ml or more and 1.0 seconds / 300 ml or less.

5. Furthermore, the method for producing a laminated nonwoven fabric according to claim 1 or 2, comprising drafting the fiber web B at a draft ratio of 1.03 to 1.60 before the water stream is sprayed.

6. Furthermore, the method for producing a laminated nonwoven fabric according to claim 5, comprising drafting the fiber web A at a draft ratio of 1.005 or more and 1.15 or less before the water stream is sprayed.

7. The basis weight of the aforementioned fiber web A is 10.0 g / m². ２ 40.0g / m or more ２ The following applies, and the basis weight per layer of the fiber web B is 10.0 g / m². ２ 50.0g / m or more ２ The method for producing a laminated nonwoven fabric according to claim 1 or 2, which is as follows:

8. A method for producing a laminated nonwoven fabric according to claim 1 or 2, wherein the fiber web A contains 50% by mass or more of the short fibers, and the fiber web B contains 50% by mass or more of the staple fibers.

9. The method for producing a laminated nonwoven fabric according to claim 8, wherein the fiber web A contains pulp as the short fibers.

10. The method for producing a laminated nonwoven fabric according to claim 8, wherein the fiber web A is a wet nonwoven fabric.

11. The aforementioned fiber web A is A method for producing a laminated nonwoven fabric according to claim 10, wherein the crepe ratio measured by the underwater elongation method is 10% or more and 30% or less.

12. The method for producing a laminated nonwoven fabric according to claim 8, wherein the staple fibers are cellulose fibers.

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