JPH02127552A - Wet laminate non-woven fabric for grain and production thereof - Google Patents

Abstract

PURPOSE:To obtain the title uniform non-woven fabric having extremely high strength and soft feeling and free from defect such as ARABI by laminating a specified short layer to an ultrafine short fiber and further interlacing both layers. CONSTITUTION:A paper sheet obtained from a short fiber satisfying the formulas 7mum<=D<=25mum (D is diameter of single yarn of short fiber) and 0.8X10<3=L/D<=2.0X10<3> (L is fiber length of short fiber) or paper sheet obtained by blending the above-mentioned short fiber with an ultrafine short fiber having <=0.5 denier fineness of average single fiber is laminated on one surface of a sheet obtained from the above-mentioned ultrafine short fiber by paper making method and then the above-mentioned two kind of short fibers are mutually three-dimensionally interlaced by alternately operating high speed fluid stream from both face of the laminated sheet to provide the aimed non-woven fabric.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a wet laminated nonwoven fabric for silver surfaces and a method for producing the same. More specifically, the present invention relates to a wet laminated nonwoven fabric for grain surfaces that is flexible, exhibits high peel strength, tear strength, etc., and has excellent grain surface formation properties, and a method for producing the same.

[Conventional technology]

In recent years, nonwoven fabrics have shown remarkable development, taking advantage of their excellent performance and high productivity to be used as an alternative to conventional knitted fabrics, or for functional uses that cannot be met with wav&materials. Various types of nonwoven fabrics are known, but typical ones include direct spinning of a fiber-forming polymer, such as the spun-pond method and flash spinning method, and simultaneously pulling filaments with air, gas, etc. Long fiber dry non-woven fabric obtained by accumulating, short fiber dry non-woven fabric with relatively long fiber length obtained by melt blowing method, short fiber dry fabric with relatively long fiber length obtained by the melt blowing method, short fibers are carded and then made into a sheet by cross layering, air layer etc., and depending on the purpose, needle punching or bonding. agent,
Short fiber dry nonwoven fabrics obtained by bonding with heat-fused fibers, etc., and wet nonwoven fabrics obtained by papermaking methods are known. Furthermore, many attempts have been made to process these nonwoven fabrics and apply them to substrates for silver surfaces. For example, JP-A-58-13785 proposes that a three-dimensional entangled nonwoven fabric of a melt-blown web be impregnated with an elastic polymer and solidified as a substrate for silver surfaces. Also, Japanese Patent Application Publication No. 1983-
No. 43479 and No. 56-43480 propose that a short fiber dry non-woven fabric in which ultrafine fiber bundles are entangled by needle punching is impregnated with a porous polymer mainly composed of polyurethane elastomer, and a substrate is subjected to silver surface processing. There is.

However, this type of nonwoven fabric itself is not sufficient as a substrate for silver surfaces in terms of tensile strength, tear strength, and peel strength.
In order to compensate for this, it is necessary to impregnate a large amount of polymeric elastomer such as polyurethane elastomer, but in this case, there is a drawback that the hand becomes hard and the rubbery feeling is accentuated.

On the other hand, wet-laid nonwoven fabrics are characterized by incomparably better uniformity than dry-laid nonwoven fabrics because they are formed into sheets by dispersing extremely short fibers in water. However, in order to uniformly disperse fibers in water, the fiber length is generally 3~
Since an extremely short length of about 71 mm is required, the nonwoven fabric obtained by this method has extremely low strength, and its use is limited to fields where high strength is not required. However, Japanese Patent Publication No. 52-107368 discloses a nonwoven fabric in which a reinforcing material such as a knitted fabric is inserted between sheets obtained by a papermaking method, and the reinforcing material is intertwined with the reinforcing material by a high-pressure water jet or the like. In this case, mechanical strength such as tensile strength and tear strength depends on the knitted fabric, so by appropriately selecting the knitted fabric, it is possible to impart the required strength to the grain substrate. There is a limit to the entanglement of knitted fabrics and paper-made staple fibers, and sufficient peel strength cannot be obtained.In this case, as with other nonwoven fabrics, peel strength must be ensured by impregnating the fabric with a polymeric elastic material. I don't get it. Therefore, it has the disadvantage that hand hardening is unavoidable. Conventionally, as a substrate for silver surfaces in place of knitted fabrics, non-woven fabrics impregnated with polymeric elastomer and reinforced have been used, and the non-woven fabrics themselves have excellent uniformity and various mechanical strengths. At present, there is currently no material that has both a soft texture and good grain forming properties.

[Problem to be solved by the invention]

The present invention provides wet-laid nonwoven fabrics that have the characteristics of excellent uniformity while overcoming their weak strength, and that do not impregnate polymeric elastomers or the like or attach only a small amount of them. It is an object of the present invention to provide a novel wet laminated nonwoven fabric for grain surfaces that satisfies physical properties such as sufficient peel strength and has an extremely soft texture and good grain surface forming properties just by applying the present invention, and a method for producing the same.

[Means to solve the problem]

The present inventors have diligently studied the above-mentioned problems and have arrived at the present invention. That is, the above-mentioned object of the present invention is to form a nonwoven fabric layer (A) in which ultrafine short fibers having an average single fiber fineness of 0.5 denier or less are intertwined in three dimensions, and a nonwoven fabric layer (A) in which short fibers satisfying both the following (Equation 11 and Equation (2)) are intertwined in three dimensions. A laminated nonwoven fabric consisting of entangled nonwoven fabric layers fB), wherein the nonwoven fabric layers (A) and (8) are integrally bonded by mutual entanglement of one part of short fibers constituting each layer, This is achieved by a wet laminated nonwoven fabric for silver surfaces in which the distance between fiber entanglement points of short fibers constituting the military woven fabric layer (8) is 300μ or less.

Diameter of single yarn of short fiber: D Fiber length of short fiber: L (1) Formula - 1 ----7μ floor ≦D≦25μm (2) 2...0.8× 10'≦L/D≦ 2.0X10' The manufacturing method of the nonwoven fabric for obtaining the wet laminated nonwoven fabric for silver surfaces according to the present invention is to apply the following (1 )
A paper-made sheet obtained from short fibers satisfying both formulas (2) and (2), or a paper-made sheet in which the short fibers and the ultrafine short fibers are mixed, is laminated, and then a high-speed wake is alternately treated from both sides of the laminated sheet. By doing so, the two types of short fibers are three-dimensionally entangled with each other and with each other.

Note that short fiber usually refers to one fiber. However, in technical fields related to nonwoven fabrics, bundles of a plurality of short fibers are sometimes simply referred to collectively as short fibers.

Therefore, in this specification, when it is necessary to clarify the difference, a single fiber is referred to as a "short fiber single yarn" or a "single yarn J."

In the wet laminated nonwoven fabric for silver surfaces of the present invention, the nonwoven fabric layer (A
) must be ultrafine fibers with an average single fiber fineness of 0.5 denier or less. In the case of fibers exceeding 0.5 denier, the surface is sparse, rough, and cannot be smoothed, so it is necessary to directly coat the surface with a non-porous film of elastic polymer to form a silver surface, or to apply wet coagulation to the surface. Even if a silver surface is formed by forming a foam layer and laminating a non-porous layer on top of it, a uniform and smooth silver surface cannot be obtained, and the disadvantage is that the surface is uneven, so-called "roughness". This is not desirable. In other words, in order to form a uniform and elegant silver surface, the surface must consist of a smooth and dense layer.
In order to achieve this, it is necessary to use fibers of 0.5 denier or less for the nonwoven fabric layer (A), and polyamide fibers such as nylon 6 and nylon 66 and polyethylene terephthalate fibers are preferably used. In addition to this, polybutylene terephthalate, polypropylene, polyethylene,
Even rayon and acrylic fibers can be used as fibers for the nonwoven fabric N(A) of the present invention as long as they satisfy the above-mentioned average single fiber conditions. Next, since the nonwoven fabric layer (8) in the wet laminated nonwoven fabric for silver surfaces of the present invention contributes to the development of mechanical strength such as tensile strength and tear strength of the nonwoven fabric, the nonwoven fabric layer (8) is The fiber has a single yarn diameter of 7 to 25
μm, ratio of fiber length to single yarn diameter L/D: 0.8
IO' ~2. It is necessary to satisfy both OXl03(7) knee M) elements. If the single yarn diameter is less than 7μ, even if L/D is within the above range, the single yarn tenacity is too low, so tensile strength, tear strength, etc. are especially low, and high strength cannot be obtained. . If the single fiber diameter required for the substrate for silver surfaces exceeds 25 μm, even if L/D is within the range of the present invention, the fibers will be too thick and the surface uniformity and density of the nonwoven fabric will be lost, resulting in poor texture. However, the object of the present invention cannot be achieved. The preferable range of the single yarn diameter is 7 to 25 μm in terms of strength, (uniformity) and flexibility.

Next, the fiber L/D is 0.8 within the above fiber diameter range.
It needs to be between X10' and 2.0X103. Fiber L
The inventors have found that /D has an important relationship with the ease with which fibers are entangled with each other, and L/D is 0.
．． When it is less than 8X103 and when it exceeds 2.0X103, the desired nonwoven fabric strength cannot be obtained,
Practical high strength can only be obtained in the range of 0.8X10' to 2.0X103 according to the present invention. This surprising fact can be estimated as follows.

That is, the ease of movement of the fibers due to columnar water flow, etc. is greater as L/D is smaller, that is, the thicker and shorter the fibers are, and the entanglement between the fibers becomes greater. On the other hand, the number of contact points between fibers increases as the fibers become thinner and longer, that is, the L/D becomes larger. However, L/D
If it is too large, the movement of the fibers during intertwining will be suppressed and the entanglement between the fibers will become smaller. Therefore, it is understood that there is an optimal range of L/D in which the fiber-to-fiber intertwining density is maximum, and this range is o,5xto' to 2.0x10''.

The laminated type 28 nonwoven fabric for grain surfaces of the present invention has a composition fiber of 0.000 to form a grain surface layer that is uniform and free from defects such as "roughness."
In order to contribute to the development of sufficiently strong strength without impregnating the nonwoven fabric layer (A) in which ultrafine short fibers of 5 deniers or less are three-dimensionally intertwined with a binder between the polymer elastic body and the fiber diameter specified above, A wet-laid nonwoven fabric formed by laminating a nonwoven fabric (layer thickness) in which short fibers having L/D are three-dimensionally entangled, and the nonwoven fabric layer (A) and the nonwoven fabric layer (8) are made of short fibers constituting each layer. An important component of the present invention is that the parts are integrally connected by three-dimensional entanglement. Furthermore, as an essential component of the present invention, the short fibers constituting the military woven fabric layer must be three-dimensionally intertwined closely to a state where the distance between fiber entanglement points M is 300 μm or less.

Even if the shapes of the short fibers constituting the nonwoven fabric layer (A) and the nonwoven fabric layer (8) satisfy the constituent requirements of the present invention, the three-dimensional entanglement of the short fibers is insufficient and the fiber entanglement of the nonwoven fabric layer (8) is insufficient. A relatively loose entangled state in which the distance between points exceeds 300 μm does not provide sufficient strength to serve as a substrate for a silver surface, which is the object of the present invention, and is therefore not included in the present invention.

Regarding the diameter of the single yarn constituting the present invention, the single yarn may have a circular cross section or various non-circular cross sections. In the case of a circular shape, the diameter of the single yarn is determined by directly measuring its diameter.In the case of a yarn with an irregular cross section, the diameter of the single yarn is determined by measuring its fineness (denier) using the gravimetric method, and this denier is determined as the diameter of the single yarn. It will be expressed by the average diameter obtained by the following formula when it is assumed that is circular.

(Here, R = Diameter of single yarn (μm) S = Density of polymer constituting single yarn (g/cm') d = Fineness of single yarn (denier) 1 Circumference) Fiber entanglement here What is the distance between points?
It is a value measured by the following method known in 280,
This is a measure of the intertwining density between fibers, and the smaller the value, the denser the intertwining. FIG. 1 is an enlarged schematic diagram of the constituent fibers of a wet-laid nonwoven fabric when observed from the surface in a plane direction. Let the constituent fibers be f,,f,,f.

..., let the point where any two of them intertwine f, f2 be al, and trace it to the point where the upper fiber f2 intersects under the other fiber, Let the point of intersection be az. Similarly, it is assumed that a3+a4... Next, the linear-horizontal ratio M aI aZ + aZ ``3... between the interlacing points obtained in this way is measured, and the average value of these many measured values is determined, and this is taken as the distance between the fiber interlacing points.

The fibers constituting the nonwoven fabric layer (B) of the wet laminated nonwoven fabric of the present invention are polyamide fibers such as nylon 6, nylon 66, and nylon 610, polyester fibers such as polyethylene terephthalate and polybutylene terephthalate, and polyolefin fibers such as polypropylene and polyethylene. , regenerated cellulose fibers such as rayon, etc. are preferably used within the fiber diameter and L/D range of the present invention. In addition, it is preferable that the Young's modulus of the raw yarn is in the range of 50 to 700 kg/llll112, and the width Lt is in the range of 50 to 500 kg/mm.The raw yarn with a high Young's modulus of more than 700 kg/mmz also has high bending rigidity. In order to achieve the intertwined state in which the distance between intertwined points is 300 μm or less as used in the present invention, problems may occur such as the need for a large intertwining force (for example, a columnar water stream with very high pressure).

In the wet laminated nonwoven fabric for silver surfaces of the present invention, the nonwoven fabric layer (A
) The ratio of the basis weight of the ultrafine short fibers constituting the nonwoven fabric layer (8) to the short fibers having a specific shape constituting the nonwoven fabric layer (8) is preferably 10/90 to 70/30. If the ultrafine short fibers are less than 10%, the surface layer forming the grain layer will not have sufficient uniformity and smoothness, and a beautiful grain layer will not be obtained.On the other hand, if the ultrafine short fibers exceed 70%, It is not possible to obtain sufficient tear and tensile strength as a substrate for silver surfaces.

The wet laminated nonwoven fabric of the present invention is used as it is as a substrate for a silver surface, and a solution or emulsion of an elastic polymer such as polyurethane, vinyl chloride, SBR, NBR, MBR, etc. is applied on the surface of the nonwoven fabric layer (A) by gravure, and the laminated nonwoven fabric is Because it has very high tensile, tear, and peel strength as it is, there is no need to impregnate it with an elastic polymer such as polyurethane as a bonding agent and dry or wet solidify and fill it before forming the grain layer. Although it is possible to obtain silver-like artificial leather with a soft texture, a small amount of elastic polymer is filled into the wet laminated nonwoven fabric of the present invention in order to obtain a soft texture with abrasion resistance and a sense of fullness on the back side. Forming a grain layer after this does not affect the present invention in any way. In this case, the amount of impregnated elastic polymer is preferably 20% or less of the weight of the nonwoven fabric.

Further, it is preferable to mix ultrafine fibers of 0.5 denier or less in the nonwoven fabric layer (B) of the present invention in order to obtain a more uniform and dense nonwoven fabric, but mixing a large amount of ultrafine fibers causes a decrease in strength, making it undesirable. It's not right. The mixing ratio of ultrafine short fibers in the nonwoven fabric layer (8) is preferably in the range of O/100 to 50150 (ultrafine short fibers/specifically shaped short fibers).

Next, a method for producing a laminated nonwoven fabric for silver surfaces according to the present invention will be explained.

First, ultrafine fibers of 0.5 denier or less are cut into short fibers. The cut length varies depending on the denier of the single yarn in terms of uniform dispersibility in water, but generally, if it is 0.1 to 0.5 denier, it will be 3 to 5 strands, and if it is 0.1 denier or less, it will be 3 strands or less. is selected.

The obtained ultrafine short fibers are dispersed in water to a concentration of 1 to 3% O to prepare a slurry. At this time, it is preferable to add a small amount of a dispersant. This slurry is formed into a paper sheet using a fourdrinier type or circular net type paper machine. Next, single yarn diameter 7
~25μm, L/D 0.8×10'3~2X10
'Prepare short fibers with a specific shape. Using this fiber, a paper sheet is formed in the same manner as the ultrafine short fibers described above.

Alternatively, the ultrafine short fibers at the tip and the single yarn diameter 7 to 25 μm, ■, /
Form a mixed paper sheet with short fibers having a specific shape of D O,8xlO'~2X10''.In this case, the ratio of ultrafine short fibers to short fibers having a specific shape is 0:100~
50 : 50 (7) Range te If ultrafine short fibers are mixed in exceeding 50 : 50, the strength of the short fibers in the nonwoven fabric layer (8) will decrease, resulting in insufficient strength development of the laminated nonwoven fabric, resulting in lower tensile strength and tear strength. It may be undesirable as a substrate for silver surfaces. A paper sheet of ultra-fine short fibers obtained as described above and a paper sheet of short fibers with a specific shape, or a mixed sheet of short fibers with a specific shape and ultra-fine short fibers are laminated and entangled with a high-speed fluid flow. . The fluid here refers to liquid or gas, and water is most preferable in terms of ease of handling, cost, and high collision energy as a fluid. When using water, the water pressure varies depending on the type of yarn used and the basis weight of the laminated paper sheet, but the distance between fiber entanglement points of the fiber layer consisting of short fibers of the military woven fabric layer (8) is 3.
5-200 kg/c+ to get 00 pm
+1, preferably 10/80 kg, alternately collide from both sides of the laminated sheet. In the case of the same raw material fiber composition,
The water pressure in the lower strokes is low, and the higher the basis weight, the higher the water pressure should be set. Further, in the case of the same basis weight, when raw yarn with a high Young's modulus is used as short fibers having a specific shape, high strength, which is the object of the present invention, can be obtained by treating with a water stream of higher pressure. The diameter of the nozzle that sprays the water stream is 0.01 to 1
I prefer you. The shape of the trajectory of the water stream may be a straight line parallel to the direction of travel of the paper-made sheet, or it may be a curved shape obtained by the rotational motion of a belly button with a nozzle attached or the vibration motion that reciprocates at right angles to the direction of travel of the sheet. It's okay. The intertwining of multiple circular water flow trajectories obtained by rotational motion increases the jetting area of the water jet against the sheet per nozzle, which is efficient, but at the same time, the water flow trajectories may reduce the product value depending on the application. It is preferable because it has advantages such as less visible spots and a small strength ratio of warp to warp of the nonwoven fabric. The number of times the paper sheet is treated with high-speed water flow may be determined to be optimal depending on the purpose. The hydraulic conditions for the columnar flow treatment of these laminated sheets are three-dimensional entanglement of ultrafine short fibers, single yarn diameter of 7 to 25 μm, and L/D of 0.8.
The intertwining of specific shaped short fibers of X10' to 2 It is selected under such conditions as to obtain a thickness of 300 μm or less and to obtain uniformity.

〔Example〕

Hereinafter, the present invention will be explained in more detail with reference to Examples.

In the Examples, the measured values were determined by the following method, and all percentages are by weight.

1) Tensile strength: JTSL1096 strip method 2
) Tear strength: JISL1096 Single Kung method 3) Peel strength: JISK6328 Peeling test method for rubberized fabric 4) Flexibility: JISL1096 45° cantilever method 5) 1M! i Distance between fiber intertwining points: Measured with a scanning electron microscope at a magnification of 100 times, and the average value of 50 points was taken.

A 100 g/m ultra-fine short fiber sheet made from polyethylene terephthalate fiber with a single yarn fineness of 0.1 denier and a fiber length of 5 denier, and a 1.5 denier sheet made of nylon 6 fiber (13,
1,17111), fiber length 12.5mm (L/
D = 0.95XlO'') 200g/m
The sheets are laminated, and this laminated paper sheet is produced with a nozzle diameter of:
0.2 fin, nozzle pinch: 5 angles, number of nozzle rows 18 rows, spacing between laminated paper sheet and nozzle 3ON1 nozzle header rotation speed: 150 rpm, sheet speed 5 m/min, columnar flow treatment from the ultrafine short fiber side and nylon The test was performed once each from the 6-fiber side. The distance between fiber entanglement points of the nylon 6 fibers of this interlaced laminated nonwoven fabric was 100 pm, and the strength properties of the nonwoven fabric were high as shown below.

Tensile strength (vertical/horizontal) 12.9/11.6kg/c
m Tear strength (vertical/horizontal) 5.715.2kir Peel strength (horizontal) 2゜l kg/cm Polybutylene adipate, P, P' diphenylmethane diisocyanate, ethylene were applied to the surface of the ultrafine fiber layer of this laminated nonwoven fabric using a gravure roll. It was coated with 30% dimethylformamide having the composition of gelcol, coagulated in water, and then dried. Furthermore, polyethylene gelcol, P
, P'diphenylmethane diisocyanate, a 40% solution of a mixed solvent of 1,000 tons of methyl ethyl ethylenediamine and isopropyl alcohol was coated on a gravure roll, and the solvent was removed by drying at 130°C. The grain-like sheet material thus obtained has a polyurethane grain layer with extremely good surface smoothness, excellent flexibility in texture, and physical properties that can be applied to sports shoes, for example, as shown below. It had sufficient strength.

Tensile strength (vertical/horizontal) 25.2/ 24.5kg/
cm tear strength (vertical/horizontal) 5.3/5.0
kg/cm Peel strength (horizontal) 6.5 kg Flexibility 78 1/1 50 g/m paper-made sheet made of 0.2 denier nylon 6 fibers, 5 carbon 1 ultrafine short fibers, and nylon 6 fibers
6 fibers 1 denier (10,7μm), 10 cranes (L/
D = 0.93 x 10") sheets made of short fibers were laminated. This was subjected to columnar flow treatment under the same conditions as in Example 1 (only the water pressure conditions were changed) to obtain a laminated nonwoven fabric. The nylon of this laminated nonwoven fabric The distance between fiber entanglement points observed from the 66 fiber layer surface was 90 μm.

Moreover, the strength of the obtained laminated nonwoven fabric is shown below.

Tensile strength (vertical/horizontal) 9.5/8.7 kg/
am Tear strength (vertical/horizontal) 3.8/3.4 kg Peel strength (horizontal) 1.6 kg A polyurethane grain layer was formed on the surface of the nylon 6 ultrafine fiber layer of this laminated nonwoven fabric in the same manner as in Example 1. The surface of the obtained silver-like artificial leather is smooth and uniform, and it also exhibits an extremely soft texture and the physical properties shown below, and can be used, for example, as an upper material for women's shoes and a shoe sole material. Ta.

Tensile strength: 17.0/15.1 kg/am Tear strength: 4.3/4.1 kg Peel strength: 1.6
kg Flexibility; 58 Nylon 6 fibers 1.
5 denier (13,1μIII), fiber length 12.5n (
L/D=0.95xlO') fiber and PETo, 15 denier, fiber length 5x ultrafine fiber in weight ratio N6:PE
Mixed sheets of 250 g/m obtained by mixing at T=7:3 were laminated. This was carried out under the same conditions as Example 1 (
(Only the water pressure conditions were changed) Columnar flow treatment was performed to obtain a laminated nonwoven fabric.

The distance between fiber entanglement points on the side of the mixed sheet layer of nylon 6 fibers and PET ultrafine fibers in this laminated nonwoven fabric was 200 μm.

In addition, the strength and physical properties of this nonwoven fabric are shown below.

Tensile strength (vertical/horizontal) 18.1/17.5kg/c
m tear strength (vertical/horizontal) 7.2/6.5 + r peel strength (horizontal) 2.6 kg/us Furthermore, using this laminated nonwoven fabric as a base, non-yellowing type polyurethane elastomer ("Chrisbon 33554 Dainippon Ink A 10% solution (isopropyl alcohol/toluene = 1:1 mixed solvent) of Kagaku Kogyo KK) with 15% brown pigment added to the resin was applied with a gravure roll and dried.Furthermore, on top of this colored layer Isopropyl alcohol/toluene/DMF (=515/1) solution of non-yellowing type polyurethane elastomer (resin concentration 1O%)
was gravure coated and dried. Next, it was finished by embossing and kneading.

The obtained silver-faced sheet material has a surface with uniform creases, exhibits extremely high physical properties (see below) and a soft texture, and can be used, for example, as an upper material for men's shoes or an upper material for sports shoes. It was applicable. Tensile strength (vertical/horizontal) 30.1/28.6kg/c
+a Tear strength (vertical/horizontal) 6.315.7 kg Peel strength (horizontal) 8.2 kg Flexibility 82 times 1 [Effects of the invention] The wet laminated nonwoven fabric for silver surfaces of the present invention has ultrafine short fiber layers and short fiber layers specified as Because the fiber layers are laminated and have a certain three-dimensional entangled structure, it has extremely high strength and a flexible texture that cannot be obtained with conventional wet-laid nonwoven fabrics, and has a uniform and smooth surface layer. Because of this, it is possible to form an excellent grain surface that is uniform and free from defects such as "roughness."

In addition, since the nonwoven fabric has a uniquely high peel strength, when used as a substrate for silver surfaces, it has such excellent characteristics that it hardly requires filling with a bonding agent, which is essential for conventional nonwoven fabrics.

[Brief explanation of the drawing]

FIG. 1 is an enlarged schematic diagram of the constituent fibers when observed from one surface in the planar direction of the nonwoven fabric of the present invention. f, -f7... Constituent fibers, a, ~a,... Intertwining points of constituent fibers.

Claims (2)

[Claims] 1. A nonwoven fabric layer (A) in which ultrafine short fibers with an average single fiber fineness of 0.5 denier or less are three-dimensionally entangled, and the following formula (1), (2)
Nonwoven fabric layer (8) in which short fibers are three-dimensionally entangled, both satisfying the formula
A laminated nonwoven fabric consisting of the nonwoven fabric layer (A) and (
8) are integrally bonded together by mutual entanglement of a portion of the short fibers constituting each layer, and the nonwoven fabric layer (
The distance between fiber entanglement points of short fibers constituting B) is 300 μm
A wet laminated nonwoven fabric for silver surfaces as follows. Diameter of single fiber of short fiber: D Fiber length of short fiber: L Formula (1)...7μm≦D≦25μm (2) Formula...0.8×10^3≦L/D≦2.0×10
^32. On one side of a sheet obtained by a paper-making method from ultrafine short fibers having an average single fiber fineness of 0.5 denier or less, a sheet made from short fibers that satisfies both formulas (1) and (2) below or the short fibers and the above-mentioned short fibers are applied. The silver is characterized in that the two types of short fibers are three-dimensionally entangled with each other and with each other by laminating paper sheets in which ultrafine short fibers are mixed and then applying high-speed fluid flow alternately from both sides of the laminated sheets. A method for producing a wet laminated nonwoven fabric for surfaces.