JP2007247079A - Laminated nonwoven fabric and synthetic leather using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To inexpensively provide a laminated nonwoven fabric having the surface excellent in fineness and flexibility, expressing little bony appearance when bending stress is acted, especially suitable for applying to a synthetic leather base fabric. <P>SOLUTION: The laminated nonwoven fabric is prepared by laminating through mechanical interlacing of a fiber structural body comprising a fiber having a fineness of 0.0001-0.5 dtex and a basis weight of 40-150 g/m<SP>2</SP>in the upper layer and a fiber structural body comprising a fiber having a fineness of 1.5-10.0 dtex fineness and a basis weight of 40-200 g/m<SP>2</SP>in the lower layer, and satisfies the following (a)-(c): (a) density is 120-250 kg/m<SP>3</SP>, (b) rupture strength is 400-1000N (c) bending stiffness is 1-120 mm. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a laminated nonwoven fabric that is flexible and profound, and more specifically, the upper layer is dense and excellent in flexibility, has less susceptibility to bending stress, and the lower layer inhibits the flexibility of the upper layer. In particular, the present invention relates to a laminated nonwoven fabric that is suitable for use in synthetic leather, with the thickness taken into account.

Non-woven fabrics are used for applications that require high strength properties such as civil engineering and industrial materials due to the balance between their superior performance and cost, and also those that require texture and softness properties such as clothing and sanitary materials. And so on. In particular, in the latter application, nonwoven fabrics entangled with a needle punch or the like are widely used because of demands for flexibility and texture. However, when a bending stress is applied to such a nonwoven fabric, wrinkles (hereinafter referred to as erection) occur at the boundary between the fiber entanglement, in other words, the portion where the fiber density is high and the portion where the fiber density is low. There was a problem.
Therefore, many attempts have been made to construct with ultrafine fibers having a small constituent fiber fineness in order to eliminate the standing by making the surface more precise.

For example, a proposal has been made to make the constituent fibers fine by subjecting the constituent fibers to chemical treatment and dissolving a part of the constituent fibers. In addition, there is a method in which a non-woven sheet made of splittable composite fibers is subjected to a high water pressure water flow treatment to be split. These have been proposed to be made ultrafine by performing warm water treatment and dissolving some of the constituent fibers (see, for example, Patent Document 1).

Moreover, the method of performing a chemical | medical agent process and making it ultrafine similarly to the above is disclosed (for example, refer patent document 2). Further, there has been proposed a nonwoven fabric with improved flexibility by improving the method to lower the drawing condition of the yarn-making condition to a lower magnification and not having a highly oriented / highly crystallized fiber (see, for example, Patent Document 3). . However, these conventional techniques require a chemical treatment step, which is disadvantageous in terms of cost and difficult to control the variation in the amount of dissolution, which is not preferable in terms of providing uniform flexibility. In addition, since these nonwoven fabrics use ultrafine fibers, it is extremely difficult to impart a profound feeling, and thus the demands of the market cannot be satisfied.
JP 2000-273769 A JP 2005-299041 A JP-A-2004-84076

  The present invention was made in the background of the above-mentioned problems of the prior art, and it is an object to provide industrially efficiently a laminated nonwoven fabric having a dense surface and excellent flexibility, and less erection property when a bending stress is applied. It is what.

The present invention has finally been completed as a result of intensive studies to solve the above problems. That is, the present invention is as follows: (1) The basis weight is 40 to 150 g / m2 in the upper layer and the basis weight is 40 to 200 g / m2 in the fiber structure mainly composed of fibers having a fineness of 0.0001 to 0.5 dtex. A laminated nonwoven fabric characterized in that a fiber structure having a fineness of 1.5 to 10.0 dtex is laminated by mechanical entanglement and satisfies the following (a) to (c).
(A) Density is 120 to 250 kg / m3
(B) Burst strength is 400 to 1000 N
(C) The bending resistance is 1 to 120 mm or less. (2) The fiber constituting the upper layer is a split fiber, (3) The laminated nonwoven fabric according to (1), wherein the lower layer has an initial stress. The laminated nonwoven fabric according to (1) or (2), which is a fiber structure of 0.1 to 40 N / 5 cm in both length and width, (4) at least 2 entanglement treatment by hydroentanglement and / or needle punching The laminated nonwoven fabric according to any one of (1) to (3), wherein the laminated fibrous structure is a polyester-based long-fiber nonwoven fabric. (1) to (4) The laminated nonwoven fabric according to any one of (2) to (6), wherein the fibers constituting the upper fiber structure are split during and / or after lamination. (5) The laminated nonwoven fabric according to any one of (7) and (1) (6) any combination skin synthetic leather sheet is synthetic leather leather sheet coated with polyurethane resin in the laminated nonwoven fabric is characterized by satisfying the following following (a) ~ (d) described.
(A) Tensile strength is 200 to 1000 N / 3 cm
(B) Tear strength is 20 to 200 N
(C) Burst strength is 150 to 1000 N
(D) Thickness 0.8-2.0mm
It is.

  According to the present invention, there is an advantage that it is possible to provide a low-cost laminated nonwoven fabric particularly suitable for synthetic leather base fabrics, which has a dense surface, excellent flexibility, and less erection when subjected to bending stress. .

Hereinafter, the present invention will be described in detail.
The laminated nonwoven fabric in the present invention is composed of fibers having a fineness of 0.5 dtex or less, or a fiber structure (upper layer) as a main component and a nonwoven fabric (lower layer) having a fineness of 1.5 to 10.0 dtex. It is preferable.
This is because by setting the upper layer to a fineness of 0.5 dtex or less, a laminated nonwoven fabric having a high density and almost no skeletalness and excellent in texture and flexibility particularly preferred by consumers. However, the fiber structure that constitutes the upper layer lacks a profound feeling, and, for example, interiors that use synthetic leather, such as interiors that require a profound feeling with a profound feeling, satisfy the consumer's preference sufficiently. Can not do it. Also, it is theoretically possible to produce a thick non-woven fabric made only of ultrafine fibers, but neglecting industrial productivity, it becomes thicker because the density increases. Therefore, by laminating and integrating a nonwoven fabric with a fineness of 1.5 to 10.0 dtex as the lower layer, the synthetic leather using it is excellent in mechanical properties such as breaking strength, is flexible and lightweight, and has very little skeletalness. A profound interior can be obtained.

The lower limit of the fineness of the upper fiber structure is not particularly limited, but is preferably 0.0001 dtex or more from the viewpoint of maintaining the strength of the laminate. The fineness of the upper fiber structure is more preferably 0.01 to 0.4 dtex or less, and still more preferably 0.1 to 0.3 dtex or less.

Moreover, if the lower layer fiber structure is a fiber structure of 1.5 to 10.0 dtex, a laminated nonwoven fabric having both bulkiness and flexibility can be obtained. A more preferable fineness of the fibers constituting the lower fiber structure is 1.5 to 8.0 dtex, and more preferably 2.0 to 6.0 dtex.

The basis weight of the upper fiber structure constituting the laminate of the present invention is preferably 40 to 150 g / m 2, more preferably 50 to 140 g / m 2, and still more preferably 60 to 120 g / m 2.
If the basis weight is 40 g / m 2 or more, the effect of preventing bone formation due to densification can be exhibited extremely effectively, and mechanical entanglement with the needle punch or water punch with the lower layer is effective in the range not exceeding 150 g / m 2. Because it is done.

Examples of the method for producing the upper-layer fiber structure include a melt blown method, a method of carding short fibers, and a spunbond method in which long fibers stretched by an ejector and a roller are deposited on a collection net conveyor. Is not to be done.

The material constituting the upper layer is preferably split fiber, and particularly preferably incompatible with each other so as to be easily split when an impact is applied to a single yarn. Moreover, it is preferable that it is a fiber which consists of two or more types of polymers. Ultrafine fibers are difficult to mechanically entangle with other materials such as spunbond nonwoven fabrics. If split fibers, needle punch / water punch, etc. before thinning or simultaneously with split fibers This is because entanglement can be strongly imparted during mechanical entanglement, and an ultrafine fiber laminate that is difficult to peel off can be obtained. For these reasons, the fibers constituting the upper layer of the laminated nonwoven fabric of the present invention are preferably split fibers after mechanical entanglement and / or mechanical entanglement.

Examples of the cross-sectional shape of the fibers forming the upper layer of the nonwoven fabric laminate of the present invention include multi-layer laminated latent split fibers, hollow multi-layer laminated split fibers, petal cross-section latent split fibers, hollow petal cross-section latent split fibers, and the like. When the two components are respectively component A and component B, both polymers of AB can be arbitrarily selected as long as they are combined in consideration of the balance of SP value (solubility parameter) and dissolution viscosity. For example, polyester copolymers such as polyethylene terephthalate, polytrimethylene terephthalate and polybutylene terephthalate, polyolefin polymers represented by polyethylene and polypropylene, polyamides represented by nylon 6 and nylon 6 and nylon 66 In addition to polymers, other examples include polystyrene polymers, polyvinyl alcohol polymers, vinyl alcohol ethylene copolymers, and the like. Each component includes one kind of polypropylene, nylon 6, polyethylene and the like.

  The basis weight of the lower layer fiber structure is preferably 40 to 200 g / m 2, more preferably 50 to 180 g / m 2, and still more preferably 60 to 160 g / m 2. By making it 40 g / m2 or more, a profound feeling can be obtained in the nonwoven fabric laminate, and if it is in a range not exceeding 200 g / m2, it does not hinder excellent anti-skipping properties due to densification of the upper layer, and has an excellent texture. This is because a heavy laminated nonwoven fabric can be obtained.

  The lower layer fiber structure preferably has an initial stress of 0.1 to 40 N / 5 cm in both length and width. As described above, it is difficult to laminate fibers having small fineness by mechanical entanglement, and if the initial elastic modulus of the lower fiber structure is in the range, the upper layer is exerted with the effect of reinforcing the upper layer. Strong entanglement between the fiber and the underlying fiber is obtained. Moreover, combined with the fact that the nonwoven fabric laminate itself becomes flexible, it is possible to obtain a laminated nonwoven fabric that is strong and has a strong sense of integrity as if it is composed of one upper layer. A more preferable initial stress is 1 to 20 N / 5 cm, and a further preferable initial stress is 3 to 10 N / 5 cm.

  The lower layer can be obtained by a conventional method such as a melt blow method or a spun bond method. In particular, when considering an appropriate fiber diameter and productivity, a nonwoven fabric obtained by a spunbond method is preferable. The spunbond method includes, for example, a round cross-section spinneret and a rectangular cross-section spinneret, but it is preferable to use a rectangular cross-section spinneret having a relatively good fiber accumulation distribution in the direction orthogonal to the machine direction. preferable. In order to facilitate fiber entanglement by needle punching, the temporary bonding temperature is preferably Tm-100 ° C to Tm-10 ° C, more preferably Tm-80, with respect to the melting point (Tm) of the polymer used. To Tm-30 ° C. For this reason, it is difficult to maintain the shape of the desired long fiber fleece at a temperature lower than Tm-100 ° C, and conversely, at a temperature higher than Tm-10 ° C, there is a fusion zone during fiber entanglement by needle punching. This is because it has already occurred and it becomes difficult to confound. In addition, as a temporary bonding method, for example, a long fiber fleece is generally inserted between hot rolls. Even under such weak thermocompression bonding conditions, according to the present invention, mechanical entanglement is added during lamination with the upper layer, and thus problems such as fluffing hardly occur.

Further, the bonding area of the hot roll is not particularly limited because it is appropriately determined depending on the relationship with the bonding pressure.
The density of the laminate is preferably 120 to 250 kg / cm 3, more preferably 130 to 240 kg / cm 3, and still more preferably 140 to 230 kg / cm 3. When the density of the laminate is less than 120 kg / cm 3, bone density occurs due to insufficient denseness, which is not preferable. In addition, when the density of the laminate exceeds 250 kg / cm 3, it is not preferable to reduce the thickness, for example, when polyurethane is foamed to make synthetic leather, because the sense of quality is impaired.

  The burst strength (JIS L1906 A method) of the laminate is 400 to 1000 N, preferably 500 to 900 N, more preferably 500 to 900 N. If it is 400 N or less, for example, when used for interior applications such as chairs, the problem of tearing during expansion is unlikely to occur, and the application range is expanded.

  The bending resistance of the laminate is preferably 1 to 120 mm, more preferably 50 to 120 mm, and still more preferably 70 to 100 mm. This is because if it has a flexibility of 1 to 120 mm, it does not impair the characteristics of the laminated nonwoven fabric of the present invention that prevents the occurrence of bone formation by densifying the upper layer.

  As a method of laminating the upper layer fiber structure and the lower layer fiber structure, it is preferable to perform mechanical entanglement by water punch and / or needle punch processing. According to this method, a flexible laminated nonwoven fabric can be obtained, and at the same time, when a split fiber is used for the upper layer, splitting can be performed simultaneously with lamination.

Moreover, it is preferable that the laminated nonwoven fabric of this invention implements a war punch and / or a needle punch at least twice. By providing mechanical entanglement in such a range, fiber entanglement is extremely strong and a laminated nonwoven fabric with strong integrity is obtained, and the initial elastic modulus is low, that is, the shortcoming of the lower fiber bond is compensated for, Furthermore, when split fiber is used, the fiber is sufficiently divided. From the viewpoint of flexibility, it is preferable to perform water punching at least once.

  When water punch and / or needle punch processing is carried out twice or more with the laminated nonwoven fabric of the present invention, the first processing is performed so that the needle or water flow is inserted from the lower layer surface and inserted from the upper layer surface after the second time. It is preferable to do. By performing the first processing from the lower surface, the unity becomes extremely strong. Then, by processing from the upper layer surface in the second and subsequent processing, the fiber is sufficiently divided, and as a result, a heavy and flexible laminated nonwoven fabric with extremely strong integrity and little susceptibility is obtained. It is done.

The upper limit of the number of times of performing the war punch and / or the needle punch is not particularly limited. However, if the war punch and / or the needle punch are performed 20 times or more, the damage to the fabric increases.

  It is preferable to use a polyester-based long fiber nonwoven fabric for the lower layer fiber structure in the present invention. In particular, it is more preferable to use polytrimethylene terephthalate or polybutylene terephthalate in order not to expose the susceptibility that is the subject of the present invention.

The tensile strength of the synthetic leather sheet which apply | coated the polyurethane resin to the laminated nonwoven fabric is 200-1000 N / 3cm. Preferably it is 200-800 N / 3cm, More preferably, it is 200-400 N / 3cm. This is because within this range, industrial production is possible without causing a problem of breakage during molding.

The tear strength is preferably 20 to 200N. More preferably, it is 20-100N, More preferably, it is 20-50N. If the tear strength is 20 N or less, the sewing strength is not preferable in terms of form stability and handleability.

The burst strength is 150 to 1000N. Preferably 400 to 1000N, more preferably 500 to 800N
It is. When the burst strength is 150 N or less, the synthetic leather is broken after molding or at the time of molding.

The thickness of the synthetic leather is preferably 0.8 to 2.0 mm. More preferably, it is 0.8-1.5 mm, More preferably, it is 1.0-1.5 mm. Within such a range, a laminated nonwoven fabric having flexibility, profound feeling and luxury, especially when used for interior use, can be obtained as a laminated nonwoven fabric with high commercial value. Hereinafter, the laminated nonwoven fabric of the present invention will be described in more detail based on the drawings. .

EXAMPLES The present invention will be described in more detail with reference to examples below, but the present invention is not limited to these examples. The measurement methods used in the examples are as follows.
The machine direction with respect to the sample direction is hereinafter referred to as MD direction, and the direction perpendicular to the machine direction is referred to as CD direction.

(Base fabric)
<Amount per unit area (mass per unit area)>
Conforms to JIS-L1906. Specifically, test specimens of 20 cm in the MD direction and 25 cm square in the CD direction were sampled at five locations in the CD direction, the respective weights were measured, and the average value thereof was calculated. Let m2 be the basis weight.

<Thickness>
Conforms to JIS-L1906. Specifically, the measurement is carried out at 10 points with a pressure condition of 20 gf / cm 2 per 1 m of the full width of the test piece in the CD direction, and the average value thereof is calculated.

<Density>
From the basis weight and thickness determined in accordance with the above-mentioned JIS-L1906, the weight per 1 m3 is converted into the density as g / m3.

<Initial stress>
The initial stress was defined as the stress at 5% elongation in the tensile strength measured according to JIS-L1906.

<Burst strength>
Conforms to JIS-L1096 Burst Strength Method B (Constant Speed Elongation Method). Specifically, five specimens having a diameter of 8 cm were collected, and the strength to break through the specimen when the tip radius of curvature was 1.25 cm and a push rod having a diameter of 2.5 cm was pressed at a constant speed of 100 mm / min was measured. Then, the average value of these is calculated.

<Bending softness>
Conforms to JIS-L1096. Specifically, test specimens of 20 cm in the MD direction and 2.5 cm square in the CD direction were sampled at three locations per 1 m of the total test specimen width in the CD direction, and measured at a total of 6 points on the back and front based on the 45 ° cantilever method. The average value of is calculated. This method is a result of bending resistance in the MD direction, and is a result of measurement as described above with the specimen direction orthogonal to the CD direction. Further, the bending resistance described in the present invention uses a value obtained by adding the results in the MD direction and the CD direction and dividing the result by 2.
(Synthetic leather)
<Tension>
Conforms to JIS-L1096. The tensile strength was carried out on a 3 cm wide sample.
<Burst strength>
Complies with JIS-L1096 burst strength A method (Murren method).

<Sustainability>
○: Almost no wrinkle is generated when a 10 cm square sample is folded at 60 ° Δ: A little wrinkle is generated when a 10 cm square sample is folded at 60 ° ×: Many wrinkles are generated when a 10 cm square sample is folded at 60 ° Do

<Integrity>
Evaluation when a 10 cm square sample is bent by 60 ° 100.
○: Almost no peeling was observed, and the touch was the same as that of the single-layer product.
Δ: Partial peeling was observed, and the commercial value was greatly reduced.
X: Peeling was large and could not be practically used.

<Synthetic texture>
Example The texture of a sheet base material prepared by applying polyurethane resin to a base fabric was evaluated in three stages on 10 monitors randomly extracted, and the highest evaluation was the texture of the sheet and the base material.
○: Appropriate sense of fullness, profoundness and flexibility, and a high-class feel.
Δ: Softness but less profound feeling, slightly high-class feeling ×: Flexibility, especially no profound feeling, high-quality feeling

Example 1
<Laminated nonwoven fabric manufacturing process>
The upper fiber structure is made of nylon 6 and polyethylene terephthalate and has a split fiber pre-split 0.24d hollow petal split fiber composite fiber, an unsplit short fiber composite split nonwoven fabric with a basis weight of 80 g / m 2 Polybutylene terephthalate resin (melting point: 230 ° C .: hereinafter abbreviated as PBT) is spun at a spinning temperature of 260 ° C. at a single-hole discharge rate of 0.9 g / min by a known spunbond method. The filament group that was drawn and adjusted by adjusting the air source pressure so as to have a fineness of 2.0 dtex was deposited on a resin net whose speed was adjusted so that the basis weight was 100 g / m 2. A spunbonded nonwoven fabric was obtained by temporary bonding at 30 kN / m. Then, the composite nonwoven fabric was obtained by making the upper layer division | segmentation fiber nonwoven fabric and the lower layer spunbond nonwoven fabric fiber-entangled by the well-known needle punch method so that a needle may be inserted from a lower layer spunbond nonwoven fabric.
Further, the split fiber is divided and laminated by performing the high water pressure treatment method of the upper layer part fiber structure and the lower layer part fiber structure once on the upper surface and once on the rear surface twice by water punching. The upper layer and the lower layer were entangled without peeling, and the desired laminated nonwoven fabric was obtained. The SEM photograph from the upper layer surface of the obtained nonwoven fabric and the SEM photograph from the lower layer surface are shown in FIGS. 1 and 2, respectively. It can be seen from FIG. 1 that a part of the lower layer spunbond fibers is exposed on the upper layer surface, and strong integrity and denseness of the upper layer part are obtained.

<Synthetic leather manufacturing process>
The laminated nonwoven fabric obtained in the above production process was attached with a PVA resin having a weight ratio of 18% by the dip nip method of an aqueous solution. These are for carrying out dimensional stability and substitution with urethane resin on the sheet itself.
The polyurethane solution was applied with a knife coater so as to have a moisture adhesion of 730 g / m 2, and PVA was washed with hot water at 60 ° C. and dried with hot air at 120 ° C.
After drying, the urethane coating weight was 220 g / m2, the synthetic leather total weight was 400 g / m2, and the thickness was 1.3 mm. The obtained member was a very soft synthetic leather with silver. The obtained synthetic leather is used for interior sofas and the like.

Examples 2-8
Polytrimethylene terephthalate having a basis weight of 100 g / m2 (Example 2), lower layer part weight 60 g / m2 (Example 3), lower layer part weight 80 g / m2 (Example 4), upper layer part weight 100 g / m2 and lower layer Part weight 80 g / m 2 (Example 5), upper layer part weight 100 g / m 2 and lower layer part polytrimethylene terephthalate 80 g / m 2 (Example 6), upper layer part weight 100 g / m 2 and lower layer part nylon 80 g / m 2 (implementation) Example 7), upper layer part weight 120 g / m 2 and lower layer part weight 80 g / m 2 (Example 8).

Comparative Example 1
In the manufacturing method of the lower layer fiber structure described in Example 1, the speed was adjusted so that the basis weight was 180 g / m2, and the upper layer fiber structure was not used. A layer long fiber nonwoven fabric was obtained.

Comparative Example 2
In the method for producing the lower layer fiber structure described in Example 1, the temperature of the embossing roller was 210 ° C., the speed was adjusted so that the basis weight was 180 g / m 2, and the upper layer fiber structure was not used. Obtained a single-layer long fiber nonwoven fabric produced using the method

Comparative Example 3
The upper layer fiber structure described in Example 1 was produced using the same method except that the short fiber composite split nonwoven fabric having a basis weight of 180 g / m 2 was used and the lower layer fiber structure was not used. A single-layer short fiber nonwoven fabric was obtained.

Comparative Example 4
The laminated nonwoven fabric produced by using the same method except that the upper layer portion and the lower layer described in Example 1 are not entangled in knee pan and only the lower surface of the water punch is entangled. Got.

Comparative Example 5
In the upper layer fiber structure described in Example 1, a short fiber composite split nonwoven fabric having a basis weight of 20 g / m 2 was used, and in the manufacturing method of the lower layer fiber structure described in Example 1, the basis weight was 160 g / m 2. In addition to adjusting the speed to m2, a laminated nonwoven fabric produced using the same method was obtained.

Comparative Example 6
A single-layer long fiber nonwoven fabric produced using the same method was obtained except that the air pressure was adjusted so that the fiber diameter was 15d in the method for producing a lower layer fiber structure described in Example 1.

Comparative Example 7
In addition to adjusting the air source pressure so that the fineness was 8.0 dtex in the method for producing a lower layer fiber structure described in Example 1, a laminated nonwoven fabric produced using the same method was obtained.

Comparative Example 6
In addition to adjusting the number of divisions so that the fineness was 1.6 dtex in the upper-layer fiber structure described in Example 1, a laminated nonwoven fabric produced using the same method was obtained.

The nonwoven fabrics and physical properties obtained from the examples and comparative examples were measured and shown in Table 1. In Table 1, “number of entanglements” refers to the number of times of mechanical entanglement processing, NP indicates needle punch processing, WP indicates water punch processing, and numbers indicate the number of processing times.

  According to the present invention, it is possible to obtain a laminated nonwoven fabric capable of forming a synthetic leather having a heavy feeling that cannot be realized with conventional woven fabrics or split fibers alone, and more specifically, the upper layer is dense and flexible. It can provide low cost non-woven fabrics that are particularly suitable for use in synthetic leather. It is great to contribute to the industry.

It is the electron micrograph taken from the upper layer part of the lamination nonwoven fabric of the present invention. It is the electron micrograph taken from the lower layer part of the lamination nonwoven fabric of the present invention.

Claims (7)

The upper layer has a basis weight of 40 to 150 g / m 2 and a fineness of 0.0001 to 0.5 dtex, and the lower layer has a basis weight of 40 to 200 g / m 2 and a fineness of 1.5 to 1.5. A laminated nonwoven fabric characterized in that a fibrous structure of 10.0 dtex is laminated by mechanical entanglement and satisfies the following (a) to (c).
(A) Density is 120 to 250 kg / m3
(B) Burst strength is 400 to 1000 N
(C) The bending resistance is 1 to 120 mm or less   The laminated nonwoven fabric according to claim 1, wherein the fiber constituting the upper layer is a split fiber.   The laminated nonwoven fabric according to claim 1 or 2, wherein the lower layer is a fiber structure having an initial stress of 0.1 to 40 N / 5 cm in both longitudinal and lateral directions.   The laminated nonwoven fabric according to any one of claims 1 to 3, wherein the laminated nonwoven fabric is laminated by performing entanglement treatment by hydroentanglement and / or needle punching at least twice. The laminated nonwoven fabric according to any one of claims 1 to 4, wherein the lower layer fiber structure is a polyester-based long-fiber nonwoven fabric.   The laminated nonwoven fabric according to any one of claims 2 to 5, wherein fibers constituting the upper-layer fiber structure are split during and / or after lamination. A synthetic leather sheet, wherein the synthetic leather sheet obtained by applying a polyurethane resin to the laminated nonwoven fabric according to any one of claims 1 to 6 satisfies the following (a) to (d).
(A) Tensile strength is 200 to 1000 N / 3 cm
(B) Tear strength is 20 to 200 N
(C) Burst strength is 150 to 1000 N
(D) Thickness 0.8-2.0mm